WorldWideScience

Sample records for montane meadow complex

  1. Using digital photography to examine grazing in montane meadows

    Science.gov (United States)

    McIlroy, Susan K.; Allen-Diaz, Barbara H.; Berg, Alexander C.

    2011-01-01

    Cattle (Bos taurus) numbers on national forests are allocated based on allotment grazing capacity, but spatial patterns of timing and density at smaller scales are difficult to assess. However, it is often in meadows or riparian areas that grazing may affect hydrology, biodiversity, and other important ecosystem characteristics. To explore real-time animal presence in montane meadows we distributed 18 digital cameras across nine sites in the Sierra National Forest, California. Our objectives were to document seasonal and diurnal presence of both cattle and mule deer (Odocoileus hemionus), identify the effects of three fencing treatments on animal distribution, and test digital photography as a tool for documenting cattle presence. We recorded 409 399 images during daylight hours for two grazing seasons, and we identified 5 084 and 24 482 cattle "marks" (instances of animal occurrence) in 2006 and 2007, respectively. Deer presence was much lower, with 331 marks in 2006 and 598 in 2007. Morning cattle presence was highest before 0800 hours both years (13.7% and 15.4% of total marks for 2006 and 2007, respectively). Marks decreased until 1100 hours and then increased around 1400 hours and remained relatively stable until 1900 hours. Marks then rose precipitously, with >20% of total marks recorded after 1900 hours both years. Deer presence was less than 10% per hour until 1800 hours, when >20% of total marks were recorded after this time both years. Among treatments, cattle marks were highest outside fences at partially fenced meadows, and deer were highest within completely fenced meadows. Our experience suggests that cameras are not viable tools for meadow monitoring due to variation captured within meadows and the time and effort involved in image processing and review.

  2. Watershed-scale modeling of streamflow change in incised montane meadows

    Science.gov (United States)

    Essaid, Hedeff I.; Hill, Barry R.

    2014-01-01

    Land use practices have caused stream channel incision and water table decline in many montane meadows of the Western United States. Incision changes the magnitude and timing of streamflow in water supply source watersheds, a concern to resource managers and downstream water users. The hydrology of montane meadows under natural and incised conditions was investigated using watershed simulation for a range of hydrologic conditions. The results illustrate the interdependence between: watershed and meadow hydrology; bedrock and meadow aquifers; and surface and groundwater flow through the meadow for the modeled scenarios. During the wet season, stream incision resulted in less overland flow and interflow and more meadow recharge causing a net decrease in streamflow and increase in groundwater storage relative to natural meadow conditions. During the dry season, incision resulted in less meadow evapotranspiration and more groundwater discharge to the stream causing a net increase in streamflow and a decrease in groundwater storage relative to natural meadow conditions. In general, for a given meadow setting, the magnitude of change in summer streamflow and long-term change in watershed groundwater storage due to incision will depend on the combined effect of: reduced evapotranspiration in the eroded meadow; induced groundwater recharge; replenishment of dry season groundwater storage depletion in meadow and bedrock aquifers by precipitation during wet years; and groundwater storage depletion that is not replenished by precipitation during wet years.

  3. Spatio-temporal patterns of tree establishment are indicative of biotic interactions during early invasion of a montane meadow

    Science.gov (United States)

    J.M. Rice; C.B. Halpern; J.A. Antos; J.A. Jones

    2012-01-01

    Tree invasions of grasslands are occurring globally, with profound consequences for ecosystem structure and function. We explore the spatio-temporal dynamics of tree invasion of a montane meadow in the Cascade Mountains of Oregon, where meadow loss is a conservation concern. We examine the early stages of invasion, where extrinsic and intrinsic processes can be clearly...

  4. Plant species distribution in relation to water-table depth and soil redox potential in montane riparian meadows

    Science.gov (United States)

    Kathleen A. Dwire; J. Boone Kauffman; John E. Baham

    2006-01-01

    The distribution of riparian plant species is largely driven by hydrologic and soil variables, and riparian plant communities frequently occur in relatively distinct zones along streamside elevational and soil textural gradients. In two montane meadows in northeast Oregon, USA, we examined plant species distribution in three riparian plant communities¡ªdefined as wet,...

  5. Plant biomass and species composition along an environmental gradient in montane riparian meadows

    Science.gov (United States)

    Kathleen A. Dwire; J. Boone Kauffman; E. N. Jack Brookshire; John E. Baham

    2004-01-01

    In riparian meadows, narrow zonation of the dominant vegetation frequently occurs along the elevational gradient from the stream edge to the floodplain terrace. We measured plant species composition and above- and belowground biomass in three riparian plant communities - a priori defined as wet, moist, and dry meadow - along short streamside topographic gradients in...

  6. Hydroclimatic alteration increases vulnerability of montane meadows in the Sierra Nevada, California

    Science.gov (United States)

    Viers, J. H.; Peek, R.; Purdy, S. E.; Emmons, J. D.; Yarnell, S. M.

    2012-12-01

    Meadow ecosystems of the Sierra Nevada (California, USA) have been maintained by the interplay of biotic and abiotic forces, where hydrological functions bridge aquatic and terrestrial realms. Meadows are not only key habitat for fishes, amphibians, birds, and mammals alike, but also provide enumerable ecosystem services to humans, not limited to regulating services (eg, water filtration), provisioning services (eg, grazing), and aesthetics. Using hydroclimatic models and spatial distribution models of indicator species, a range wide assessment was conducted to assess and synthesize the vulnerability of meadow ecosystems to hydroclimatic alteration, a result of regional climate change. Atmospheric warming is expected to result in a greater fraction of total precipitation falling as winter rain (rather than snow) and earlier snowmelt. These predicted changes will likely cause more precipitation-driven runoff in winter and reduced snowmelt runoff in spring, leading to reduced annual runoff and a general shift in runoff timing to earlier in the year. These profound effects have consequences for hydrological cycling and meadow functioning, though such changes will not occur steadily through time or uniformly across the range, and each individual meadow will respond as a function of its composition and land use history. Most vulnerable is groundwater recharge, a fundamental component of meadow hydrology. As a result of shortened snow melt period and absence of diel snowmelt fluxes that would otherwise gradually refill meadow aquifers, recharge is expected to decline due to less infiltration. Diminished water tables will likely stress hydric and mesic vegetation, promoting more xeric conditions. Coupled with greater magnitude stream flows, these conditions promote channel incision and ultimate state shift to non-meadow conditions. The biological effects of hydroclimatic alteration, such as lower mean annual flow and earlier timing, will result in an overall decrease in

  7. A subsurface model of the beaver meadow complex

    Science.gov (United States)

    Nash, C.; Grant, G.; Flinchum, B. A.; Lancaster, J.; Holbrook, W. S.; Davis, L. G.; Lewis, S.

    2015-12-01

    Wet meadows are a vital component of arid and semi-arid environments. These valley spanning, seasonally inundated wetlands provide critical habitat and refugia for wildlife, and may potentially mediate catchment-scale hydrology in otherwise "water challenged" landscapes. In the last 150 years, these meadows have begun incising rapidly, causing the wetlands to drain and much of the ecological benefit to be lost. The mechanisms driving this incision are poorly understood, with proposed means ranging from cattle grazing to climate change, to the removal of beaver. There is considerable interest in identifying cost-effective strategies to restore the hydrologic and ecological conditions of these meadows at a meaningful scale, but effective process based restoration first requires a thorough understanding of the constructional history of these ubiquitous features. There is emerging evidence to suggest that the North American beaver may have had a considerable role in shaping this landscape through the building of dams. This "beaver meadow complex hypothesis" posits that as beaver dams filled with fine-grained sediments, they became large wet meadows on which new dams, and new complexes, were formed, thereby aggrading valley bottoms. A pioneering study done in Yellowstone indicated that 32-50% of the alluvial sediment was deposited in ponded environments. The observed aggradation rates were highly heterogeneous, suggesting spatial variability in the depositional process - all consistent with the beaver meadow complex hypothesis (Polvi and Wohl, 2012). To expand on this initial work, we have probed deeper into these meadow complexes using a combination of geophysical techniques, coring methods and numerical modeling to create a 3-dimensional representation of the subsurface environments. This imaging has given us a unique view into the patterns and processes responsible for the landforms, and may shed further light on the role of beaver in shaping these landscapes.

  8. INTEGRATING GEOPHYSICS, GEOLOGY, AND HYDROLOGY TO DETERMINE BEDROCK GEOMETRY CONTROLS ON THE ORIGIN OF ISOLATED MEADOW COMPLEXES WITHIN THE CENTRAL GREAT BASIN, NEVADA

    Science.gov (United States)

    Riparian meadow complexes found in mountain ranges of the Central Great Basin physiographic region (western United States) are of interest to researchers as they contain significant biodiversity relative to the surrounding basin areas. These meadow complexes are currently degradi...

  9. Influence of Microclimate on Semi-Arid Montane Conifer Forest Sapflux Velocity in Complex Terrain

    Science.gov (United States)

    Thirouin, K. R.; Barnard, D. M.; Barnard, H. R.

    2016-12-01

    Microclimate variation in complex terrain is key to our understanding of large-scale climate change effects on montane ecosystems. Modern climate models forecast that semi-arid montane ecosystems in the western United States are to experience increases in temperature, number of extreme drought events, and decreases in annual snowpack, all of which will potentially influence ecosystem water, carbon, and energy balances. In this study, we developed response curves that describe the relationships between stem sapflux velocity, air temperature (Tair), incoming solar radiation (SWin), soil temperature (Tsoil), and soil moisture content (VWC) in sites of Pinus contorta and Pinus ponderosa distributed along an elevation and aspect gradient in the montane zone of the Central Rocky Mountains, Colorado, USA. Among sites we found sapflux velocity to be significantly correlated with all four environmental factors (p physiological differences, the highest elevation south-facing P. contorta site behaved similarly to the south-facing P. ponderosa, suggesting that environmental drivers may dominate the response. In response to Tair, peak sapflux velocity occurred at 12-13 degrees C at all sites except the mid-slope north-facing P. contorta site, which also had the lowest Tsoil. The responses of stem sapflux velocity to climate drivers indicate that forest transpiration is regulated by microclimate gradients across small spatial scales in complex terrain, which need to be characterized in order to understand broader ecosystem dynamics and the role that large-scale climate change will play in these systems.

  10. Vole-driven restoration of a parariparian meadow complex on the Colorado Plateau (south-central Utah)

    Science.gov (United States)

    Dennis M. Bramble; Jean C. Bramble

    2008-01-01

    Rapid and substantial reductions in the local density of invasive rubber rabbitbrush (Chrysothamnus nauseosus) have been achieved on a shrub-infested meadow complex solely by manipulating grazing so as to benefit the native meadow vole, Microtus montanus. The key adjustment has been a shift from spring-summer to late season grazing...

  11. Arithmetical meadows

    OpenAIRE

    Bergstra, J.A.; Middelburg, C.A.

    2009-01-01

    An inversive meadow is a commutative ring with identity equipped with a multiplicative inverse operation made total by choosing 0 as its value at 0. Previously, inversive meadows were shortly called meadows. A divisive meadow is an inversive meadows with the multiplicative inverse operation replaced by a division operation. In the spirit of Peacock's arithmetical algebra, we introduce variants of inversive and divisive meadows without an additive identity element and an additive inverse opera...

  12. Topoclimate effects on growing season length and montane conifer growth in complex terrain

    Science.gov (United States)

    Barnard, D. M.; Barnard, H. R.; Molotch, N. P.

    2017-05-01

    Spatial variability in the topoclimate-driven linkage between forest phenology and tree growth in complex terrain is poorly understood, limiting our understanding of how ecosystems function as a whole. To characterize the influence of topoclimate on phenology and growth, we determined the start, end, and length of the growing season (GSstart, GSend, and GSL, respectively) using the correlation between transpiration and evaporative demand, measured with sapflow. We then compared these metrics with stem relative basal area increment (relative BAI) at seven sites among elevation and aspects in a Colorado montane forest. As elevation increased, we found shorter GSL (-50 d km-1) due to later GSstart (40 d km-1) and earlier GSend (-10 d km-1). North-facing sites had a 21 d shorter GSL than south-facing sites at similar elevations (i.e. equal to 200 m elevation difference on a given aspect). Growing season length was positively correlated with relative BAI, explaining 83% of the variance. This study shows that topography exerts strong environmental controls on GSL and thus forest growth. Given the climate-related dependencies of these controls, the results presented here have important implications for ecosystem responses to changes in climate and highlight the need for improved phenology representation in complex terrain.

  13. A Model of Beaver Meadow Complex Evolution in the Silvies River Basin, Oregon.

    Science.gov (United States)

    Nash, C.; Grant, G.; Campbell, S. D.

    2014-12-01

    There is increasing evidence to suggest that the pervasive incision seen in the American West is due, in part, to the removal of beaver (Castor canadensis) in the first half of the 19th century. New restoration strategies for these systems focus on the reintroduction of beaver and construction of beaver dam analogs. Such dams locally raise streams beds and water tables, reconnect incised channels to their former floodplains, trap sediment, increase hydraulic diversity, and promote riparian vegetation. However, the geomorphic and hydrologic impacts of both the original beaver dams and their analogs are poorly understood. Observations in the Silvies River basin in Oregon, USA - an upland, semi-arid catchment with extremely high historic beaver populations and a presently recovering population, inform a conceptual model for valley floor evolution with beaver dams. The evolution of the beaver dam complex is characterized by eight stages of morphologic adjustment: water impoundment, sediment deposition, pond filling, multi-thread meadow creation, dam breaching, channel incision, channel widening, and floodplain development. Well-constructed beaver dams, given sufficient time and sediment flux, will evolve from a series of ponds to a multi-threaded channel flowing through a wet meadow complex. If a dam in the system fails, due to overtopping, undercutting, lack of maintenance, or abandonment, the upstream channel will concentrate into a single channel and incise, followed over time by widening once critical bank heights are exceeded. From stratigraphic, dendrochronologic, and geomorphic measurements, we are constraining average timescales associated with each stage's duration and transitional period. Measured sedimentation rates behind modern beaver dam analogs on five stream systems permit calculation of sediment flux over recent time periods, and aid in developing regional rates of sediment deposition over a range of drainage areas and gradients. Stratigraphic and

  14. Wet meadow ecosystems and the longevity of biologically-mediated geomorphic features

    Science.gov (United States)

    Nash, C.; Grant, G.; O'Connor, J. E.

    2016-12-01

    Upland meadows represent a ubiquitous feature of montane landscapes in the U.S. West and beyond. Characterized by flat valley floors flanked by higher-gradient hillslopes, these meadows are important features, both for the diverse ecosystems they support but also because they represent depositional features in what is primarily an erosional environment. As such, they serve as long-term chronometers of both geological and ecological processes in a portion of the landscape where such records are rare, and provide a useful microcosm for exploring many of the questions motivating critical zone science. Specifically, meadows can offer insights into questions regarding the longevity of theses biologically-mediated landscapes, and the geomorphic thresholds associated with transitions between metastable landscape states. Though categorically depositional, wet meadows have been shown to rapidly shift into erosional landscapes characterized by deep arroyos, declining water tables, and sparse, semi-arid ecosystems. Numerous hypotheses have been proposed explaining this shift: intensive ungulate usage, removal of beaver, climatic shifts, and intrinsic geomorphic evolution. Even less is known about the mechanisms controlling the construction of these meadow features. Evidence seems to suggest these channels oscillate between two metastable conditions: deeply incised, single-threaded channels and sheet-flow dominated valley-spanning wetlands. We present new evidence exploring the subsurface architecture of wet meadows and the bidirectional process cascades potentially responsible for their temporal evolution. Using a combination of near surface geophysical techniques and detailed stratigraphic descriptions of incised and un-incised meadows throughout the Silvies River Basin, OR, we examine mechanisms responsible both for the construction of these features and their apparently rapid transition from depositional to erosional. Our investigation focuses specifically on potential

  15. Vegetation changes in a wet meadow complex during the past half century

    Czech Academy of Sciences Publication Activity Database

    Prach, Karel

    2008-01-01

    Roč. 43, č. 2 (2008), s. 119-130 ISSN 1211-9520 R&D Projects: GA AV ČR IAA600050702; GA ČR GA526/00/1442 Institutional research plan: CEZ:AV0Z60050516 Keywords : wet meadows * degradation * succession Subject RIV: EF - Botanics Impact factor: 0.964, year: 2008

  16. Geomorphology, hydrology, and ecology of Great Basin meadow complexes - implications for management and restoration

    Science.gov (United States)

    Jeanne C. Chambers; Jerry R. Miller

    2011-01-01

    This report contains the results of a 6-year project conducted by the U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station and U.S. Environmental Protection Agency, Office of Research and Development on stream incision and meadow ecosystem degradation in the central Great Basin. The project included a coarse-scale assessment of 56 different...

  17. Contributions of gopher mound and casting disturbances to plant community structure in a Cascade Range meadow complex

    Science.gov (United States)

    M. Case; C.B. Halpern; S.A. Levin

    2013-01-01

    Pocket gophers (Geomyidae) are major agents of disturbance in North American grasslands. Gopher mounds bury existing plants and influence community structure through various mechanisms. However, in mountain meadows that experience winter snowpack, gophers also create winter castings, smaller tube-shaped deposits, previously ignored in studies of plant–gopher...

  18. Traditional Livelihoods, Conservation and Meadow Ecology in Jiuzhaigou National Park, Sichuan, China.

    Science.gov (United States)

    Urgenson, Lauren; Schmidt, Amanda H; Combs, Julie; Harrell, Stevan; Hinckley, Thomas; Yang, Qingxia; Ma, Ziyu; Yongxian, Li; Hongliang, Lü; MacIver, Andrew

    2014-06-01

    Jiuzhaigou National Park (JNP) is a site of global conservation significance. Conservation policies in JNP include the implementation of two national reforestation programs to increase forest cover and the exclusion of local land-use. We use archaeological excavation, ethnographic interviews, remote sensing and vegetation surveys to examine the implications of these policies for non-forest, montane meadows. We find that Amdo Tibetan people cultivated the valley for >2,000 years, creating and maintaining meadows through land clearing, burning and grazing. Meadows served as sites for gathering plants and mushrooms and over 40 % of contemporary species are ethnobotanically useful. Remote sensing analyses indicate a substantial (69.6 %) decline in meadow area between 1974 and 2004. Respondents report a loss of their "true history" and connections to the past associated with loss of meadows. Conservation policies intended to preserve biodiversity are unintentionally contributing to the loss of these ecologically and culturally significant meadow habitats.

  19. Complex Spatial Structure in a Population of Didymopanax pittieri, A Tree of Wind-Exposed Lower Montane Rain Forest

    Science.gov (United States)

    Lawton, Robert M.; Lawton, Robert O.

    2010-01-01

    Didymopanax pittieri is a common shade-intolerant tree colonizing treefall gaps in the elfin forests on windswept ridgecrests in the lower montane rain forests of the Cordillera de Tilarain, Costa Rica. All D. pittieri taller than > 0.5 m in a 5.2-ha elfin forested portion of a gridded study watershed in the Monteverde Cloud Forest Preserve were located, mapped, and measured. This local population of D. pittieri is spatially inhomogeneous, in that density increases with increasing wind exposure; D. pittieri are more abundant near ridge crests than lower on windward slopes. The important and ubiquitous phenomenon of spatial inhomogeneity in population density is addressed and corrected for in spatial analyses by the application of the inhomogeneous version of Ripley's K. The spatial patterns of four size classes of D. pittieri ( 20 cm dbh) were investigated. Within the large-scale trend in density driven by wind exposure, D. pittieri saplings are clumped at the scale of treefall gaps and at the scale of patches of aggregated gaps. D. pittieri 5-10 cm dbh are randomly distributed, apparently due to competitive thinning of sapling clumps during the early stages of gap-phase regeneration. D. pittieri larger than 10 cm dbh are overdispersed at a scale larger than that of patches of gaps. Natural disturbance can influence the distribution of shade intolerant tree populations at several different spatial scales, and can have discordant effects at different life history stages.

  20. Continuous 1985-2012 Landsat monitoring to assess fire effects on meadows in Yosemite National Park, California

    Science.gov (United States)

    Soulard, Christopher E.; Albano, Christine M.; Villarreal, Miguel; Walker, Jessica

    2016-01-01

    To assess how montane meadow vegetation recovered after a wildfire that occurred in Yosemite National Park, CA in 1996, Google Earth Engine image processing was applied to leverage the entire Landsat Thematic Mapper archive from 1985 to 2012. Vegetation greenness (normalized difference vegetation index [NDVI]) was summarized every 16 days across the 28-year Landsat time series for 26 meadows. Disturbance event detection was hindered by the subtle influence of low-severity fire on meadow vegetation. A hard break (August 1996) was identified corresponding to the Ackerson Fire, and monthly composites were used to compare NDVI values and NDVI trends within burned and unburned meadows before, immediately after, and continuously for more than a decade following the fire date. Results indicate that NDVI values were significantly lower at 95% confidence level for burned meadows following the fire date, yet not significantly lower at 95% confidence level in the unburned meadows. Burned meadows continued to exhibit lower monthly NDVI in the dormant season through 2012. Over the entire monitoring period, the negative-trending, dormant season NDVI slopes in the burned meadows were also significantly lower than unburned meadows at 90% confidence level. Lower than average NDVI values and slopes in the dormant season compared to unburned meadows, coupled with photographic evidence, strongly suggest that evergreen vegetation was removed from the periphery of some meadows after the fire. These analyses provide insight into how satellite imagery can be used to monitor low-severity fire effects on meadow vegetation.

  1. Meadow based Fraction Theory

    OpenAIRE

    Bergstra, Jan A.

    2015-01-01

    In the context of an involutive meadow a precise definition of fractions is formulated and on that basis formal definitions of various classes of fractions are given. The definitions follow the fractions as terms paradigm. That paradigm is compared with two competing paradigms for storytelling on fractions: fractions as values and fractions as pairs.

  2. Historical Meadow Dynamics in Southwest British Columbia: a Multidisciplinary Analysis

    Directory of Open Access Journals (Sweden)

    Dana Lepofsky

    2003-12-01

    Full Text Available The recent encroachment of woody species threatening many western North American meadows has been attributed to diverse factors. We used a suite of methods in Chittenden Meadow, southwestern British Columbia, Canada, to identify the human, ecological, and physical factors responsible for its historical dynamics and current encroachment by woody vegetation. We evaluated three hypotheses about the origin and processes maintaining the meadow: the meadow is (1 of recent human origin; (2 of ancient human origin, maintained by aboriginal burning; and (3 of ancient non-human origin, not maintained by aboriginal burning. Our data supported the idea that the meadow had ancient non-human origins and its recent history and current status have resulted from complex interactions among landform, climate, and fire. Soil properties (both horizonation and charcoal content indicate that the meadow is of ancient, non-human origin. Tree ages in the meadow and surrounding forest indicate that encroachment is recent, not related to a variety of recent human activities, and is probably a result of increasing spring temperature and decreasing spring snow depth. Although ethnographic surveys and historical documents revealed indigenous use of the general area over millennia, including the use of fire as a management tool, we found little direct evidence of indigenous use of the meadow. However, there was no proxy record of fire frequency in the meadow that we could have used to determine the role of fire in maintaining the meadow in the past, or the role of humans in igniting those fires. Thus, the historical role of humans in the maintenance of the meadow by prescribed fire remains indeterminate. Based on these conclusions, we combined hypotheses (2 and (3 into an a posteriori hypothesis that reflects changing interactions among people, fire, and climate over time. Without management intervention, we expect that tree encroachment will continue. Several general lessons

  3. Effects of tourism and topography on vegetation diversity in the subalpine meadows of the Dongling Mountains of Beijing, China.

    Science.gov (United States)

    Zhang, Jin-Tun; Xiang, ChunLing; Li, Min

    2012-02-01

    Subalpine meadows in the Dongling Mountains (located at E115º26'-115º40', N40º00'-40º05') of Beijing, China are important for tourism and the provision of ecosystem services. However, because of poor management serious degradation has occurred on these subalpine meadows. The aim of this paper is to present a quantitative analysis of effects of tourism disturbance and topography on the status and diversity of montane meadow communities and to provide direction for improved management. Sixty quadrats of 2 × 2 m(2) along 10 transects were set up to collect data on site characteristics and vegetation status. The relationships between community composition and structure, species diversity, and tourism disturbance and topographic variables were analyzed by multivariate methods (TWINSPAN and CCA). The results showed that eight meadow communities were identified by TWINSPAN. Most of them were seriously degraded. The first CCA axis identified an elevation and tourism disturbance intensity gradient, which illustrated that tourism disturbance and elevation were most important factors influencing meadow types, composition and structure. Some resistant species and response species to tourism disturbance were identified and can be used as indicator species of tourism disturbance. Species richness, heterogeneity and evenness were closely related to tourism disturbance and elevation. It is concluded that tourism disturbance must be controlled to enable grassland rehabilitation to occur in the meadows. Measures of effective management of the meadows were discussed.

  4. Equations for formally real meadows

    NARCIS (Netherlands)

    Bergstra, J.A.; Bethke, I.; Ponse, A.

    2015-01-01

    We consider the signatures Σm = (0,1,−,+,⋅,−1)  of meadows and (Σm,s)  of signed meadows. We give two complete axiomatizations of the equational theories of the real numbers with respect to these signatures. In the first case, we extend the axiomatization of zero-totalized fields by a single axiom

  5. Meadow-grass gall midge

    DEFF Research Database (Denmark)

    Hansen, Lars Monrad

    The area with meadow-grass (Poa pratensis, L.) grown for seed production in Den-mark is a significant proportion of the entire seed production. The meadow-grass gall midge (Mayetiola schoberi, Barnes 1958) is of considerable economic importance since powerful attacks can reduce the yield...

  6. Radionuclide transfer to meadow plants

    International Nuclear Information System (INIS)

    Sanzharova, N.; Fesenko, S.; Belli, M.; Arkhipov, A.; Ivanova, T.; Perepelyatnikov, G.; Tsvetnova, O.

    1996-01-01

    Experimental data on 90 Sr and 137 Cs transfer to plants of natural and semi-natural meadows selected in the main CIS region contaminated due to the ChNPP accident are discussed. The highest TF's in grass stand are obtained for peatlands, and minimal ones - for dry meadows. 137 Cs content in plants decreased after the accident, on average, by a factor of 2-4. The dynamics of 137 Cs uptake by plants depends on meadow and soil properties. The first half life of 137 Cs transfer to plants change from 2,0 to 2,2 years and the second (slower) period half life change from 4,0 to 12 years for different meadow types. 90 Sr TF's are higher than those obtained for 137 Cs. The correlation between soil parameters and TP's are shown. 137 Cs TF's in grass stand depend on meadow type and decrease in the following order: peatlands> flood plain and wet (lowland) meadows> dry meadows

  7. Influence of hiking trails on montane birds

    Science.gov (United States)

    William V. Deluca; David I. King

    2014-01-01

    Montane forests contribute significantly to regional biodiversity. Long-term monitoring data, often located along hiking trails, suggests that several indicator species of this ecosystem have declined in recent decades. Declining montane bird populations have been attributed to anthropogenic stressors such as climate change and atmospheric deposition. Several studies...

  8. RELATIONSHIPS AMONG GEOMORPHOLOGY, HYDROLOGY, AND VEGETATION IN RIPARIAN MEADOWS: RESTORATION IMPLICATIONS

    Science.gov (United States)

    Vegetation patterns and dynamics within riparian corridors are controlled largely by geomorphic position, substrate characteristics and hydrologic regimes. Understanding management and restoration options for riparian meadow complexes exhibiting stream incision requires knowledge...

  9. Groundwater, springs, and stream flow generation in an alpine meadow of a tropical glacierized catchment

    Science.gov (United States)

    Gordon, R.; Lautz, L. K.; McKenzie, J. M.; Mark, B. G.; Chavez, D.

    2013-12-01

    Melting tropical glaciers supply approximately half of dry season stream discharge in glacierized valleys of the Cordillera Blanca, Peru. The remainder of streamflow originates as groundwater stored in alpine meadows, moraines and talus slopes. A better understanding of the dynamics of alpine groundwater, including sources and contributions to streamflow, is important for making accurate estimates of glacial inputs to the hydrologic budget, and for our ability to make predictions about future water resources as glaciers retreat. Our field study, conducted during the dry season in the Llanganuco valley, focused on a 0.5-km2 alpine meadow complex at 4400 m elevation, which includes talus slopes, terminal moraines, and a debris fan. Two glacial lakes and springs throughout the complex feed a network of stream channels that flow across the meadow (~2 km total length). We combined tracer measurements of stream and spring discharge and groundwater-surface water exchange with synoptic sampling of water isotopic and geochemical composition, in order to characterize and quantify contributions to streamflow from different geomorphic features. Surface water inputs to the stream channels totaled 58 l/s, while the stream gained an additional 57 l/s from groundwater inputs. Water chemistry is primarily controlled by flowpath type (surface/subsurface) and length, as well as bedrock lithology, while stable water isotopic composition appears to be controlled by water source (glacial lake, meadow or deep groundwater). Stream water chemistry is most similar to meadow groundwater springs, but isotopic composition suggests that the majority of stream water, which issues from springs at the meadow/fan interface, is from the same glacial source as the up-gradient lake. Groundwater sampled from piezometers in confined meadow aquifers is unique in both chemistry and isotopic composition, but does not contribute a large percentage of stream water exiting this small meadow, as quantified by

  10. Micrometeorological Observations in a Sierra Nevada Meadow

    Science.gov (United States)

    Blackburn, D. A.; Oliphant, A. J.

    2016-12-01

    Mountain meadows play important roles on watershed and ecosystem services, including improving water quality, moderating runoff and providing biodiversity hotspots. In the Sierra Nevada, mountain meadows are an integral part of the mountain ecosystem and watersheds that impact more than 20 million people. Grazing, logging and other forms of anthropogenic land use in the Sierra Nevada have degraded the functioning of meadows, by altering the morphology, hydrology and vegetation. Existing meandering stream networks become incised and straightened by increased runoff, which effectively lowers the water table and completely alters the ecosystem from moist meadow sedges, grasses, and herbs to dryland grass and shrubs. Given the large growth cycle in healthy meadows, it is also expected that they sequester a significant amount of carbon and enhance atmospheric humidity through evapotranspiration, but relatively little work has been done on the bio-micrometeorology of meadows. The purpose of this study is to assess the growing season carbon, water and energy budgets of a partly degraded meadow in the northern Sierra Nevada. Loney Meadow, located at nearly 2,000 m in the Tahoe National Forest, has been identified as a degraded meadow and is scheduled to undergo restoration work to raise the water table in 2017. A micrometeorological tower with eddy covariance instruments was deployed at the site for most of the snow-free period from May to October 2016. The measurements include: fluxes of CO2, water vapor, surface radiation and energy budget components; ancillary meteorological and soil data; and an automated camera capturing daily images of the meadow surface. The poster will present diurnal and seasonal CO2 on a daily basis with a very rapid increase at the onset of the growing season.

  11. Behaviour of radionuclides in meadows including countermeasures application

    International Nuclear Information System (INIS)

    Prister, B.S.; Ivanov, Yu.A.; Perepelyatnikov, G.P.; Il'yn, M.I.; Belli, M.; Sanzharova, N.I.; Fesenko, S.V.; Alexakhin, R.M.; Bunzl, K.; Petriaev, E.P.; Sokolik, G.A.

    1996-01-01

    Main regularities of the behaviour of ChNPP release radionuclides in components of meadow ecosystems are considered. Developed mathematical model of radionuclide migration in components of meadow ecosystems is discussed. Radioecological classification of meadow ecosystems is proposed. Effectiveness of countermeasures application in meadow ecosystems is estimated

  12. Transformation of fractions into simple fractions in divisive meadows

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    Meadows are alternatives for fields with a purely equational axiomatization. At the basis of meadows lies the decision to make the multiplicative inverse operation total by imposing that the multiplicative inverse of zero is zero. Divisive meadows are meadows with the multiplicative inverse

  13. Global warming and soil microclimate: results from a meadow-warming experiment

    Energy Technology Data Exchange (ETDEWEB)

    Harte, J. [University of California, Berkeley, CA. (United States); Torn, M. S.; Chang, F. R.; Feifarek, B.; Kinzig, A. P.; Shaw, R.; Shen, K.

    1995-02-15

    We used overhead infrared radiators to add a constant increment of â15 W/m², over 2 yr, to the downward heat flux on five 30-m² montane meadow plots in Gunnison County, Colorado, USA. Heating advanced snowmelt by â1 wk, increased summer soil temperatures by up to 3°C, and reduced summer soil moisture levels by up to 25% compared to control plots. Soil microclimate response to heating varied with season, time of day, weather conditions, and location along the microclimate and vegetation gradient within each plot, with the largest temperature increase observed in daytime and in the drier, more sparsely vegetated zone of each plot. Day-to-day variation in the daily-averaged temperature response to heating in the drier zone was negatively correlated with that in the wetter zone. Our experimental manipulation provides a novel and effective method for investigating feedback processes linking climate, soil, and vegetation. (author)

  14. Man-induced transformation of mountain meadow soils of Aragats mountain massif (Armenia)

    Science.gov (United States)

    Avetisyan, M. H.

    2018-01-01

    The article considers issues of degradation of mountain meadow soils of the Aragats mountain massif of the Republic of Armenia and provides the averaged research results obtained for 2013 and 2014. The present research was initiated in the frames of long-term complex investigations of agroecosystems of Armenia’s mountain massifs and covered sod soils of high mountain meadow pasturelands and meadow steppe grasslands lying on southern slope of Mt. Aragats. With a purpose of studying the peculiarities of migration and transformation of flows of major nutrients namely carbon, nitrogen, phosphorus in study mountain meadow and meadow steppe belts of the Aragats massif we investigated water migration of chemical elements and regularities of their leaching depending on different belts. Field measurement data have indicated that organic carbon and humus in a heavily grazed plot are almost twice as low as on a control site. Lysimetric data analysis has demonstrated that heavy grazing and illegal deforestation have brought to an increase in intrasoil water acidity. The results generated from this research support a conclusion that a man’s intervention has brought to disturbance of structure and nutrient and water regimes of soils and loss of significant amounts of soil nutrients throughout the studied region.

  15. Characterizing meadow vegetation with multitemporal Landsat thematic mapper remote sensing.

    Science.gov (United States)

    Alan A. Ager; Karen E. Owens

    2004-01-01

    Wet meadows are important biological components in the Blue Mountains of eastern Oregon. Many meadows in the Blue Mountains and elsewhere in the Western United States are in a state of change owing to grazing, mining, logging, road development, and other factors. This project evaluated the utility of remotely sensed data to characterize and monitor meadow vegetation...

  16. GEOMORPHIC AND HYDROGEOLOGICAL CONTROLS ON THE DISTRIBUTION OF WET MEADOWS IN THE CENTRAL GREAT BASIN

    Science.gov (United States)

    The Great Basin is an arid landscape dominated by dryland vegetation such as big sage and xeric grasses. Meadow complexes occur in mountain drainages and consist of discrete parcels of land up to several hectares in area that are characterized by high water tables and that primar...

  17. Edificio de viviendas. Lake Meadows Chicago

    Directory of Open Access Journals (Sweden)

    Skidmore - Owings y Merrill, Arquitectos

    1958-09-01

    Full Text Available "Lake Meadows" es una amplia parcela, de cuatrocientos mil metros cuadrados, situada en las afueras de Chicago, con vistas dominantes sobre el lago Michigan. En tan bello emplazamiento se ha construido uno de los más atractivos conjuntos residenciales norteamericanos.

  18. HYDROGEOMORPHIC SETTING, CHARACTERISTICS, AND RESPONSE TO STREAM INCISION OF MONTANA RIPARIAN MEADOWS IN THE CENTRAL GREAT BASIN--IMPLICATIONS FOR RESTORATION

    Science.gov (United States)

    Riparian wet meadow complexes in the mountains of the central Great Basin are scarce, ecologically important systems that are threatened by stream incision. An interdisciplinary group has investigated 1) the origin, characteristics, and controls on the evolution of these riparian...

  19. Organic Farming Favours Insect-Pollinated over Non-Insect Pollinated Forbs in Meadows and Wheat Fields

    Science.gov (United States)

    Batáry, Péter; Sutcliffe, Laura; Dormann, Carsten F.; Tscharntke, Teja

    2013-01-01

    The aim of this study was to determine the relative effects of landscape-scale management intensity, local management intensity and edge effect on diversity patterns of insect-pollinated vs. non-insect pollinated forbs in meadows and wheat fields. Nine landscapes were selected differing in percent intensively used agricultural area (IAA), each with a pair of organic and conventional winter wheat fields and a pair of organic and conventional meadows. Within fields, forbs were surveyed at the edge and in the interior. Both diversity and cover of forbs were positively affected by organic management in meadows and wheat fields. This effect, however, differed significantly between pollination types for species richness in both agroecosystem types (i.e. wheat fields and meadows) and for cover in meadows. Thus, we show for the first time in a comprehensive analysis that insect-pollinated plants benefit more from organic management than non-insect pollinated plants regardless of agroecosystem type and landscape complexity. These benefits were more pronounced in meadows than wheat fields. Finally, the community composition of insect-pollinated and non-insect-pollinated forbs differed considerably between management types. In summary, our findings in both agroecosystem types indicate that organic management generally supports a higher species richness and cover of insect-pollinated plants, which is likely to be favourable for the density and diversity of bees and other pollinators. PMID:23382979

  20. Organic farming favours insect-pollinated over non-insect pollinated forbs in meadows and wheat fields.

    Science.gov (United States)

    Batáry, Péter; Sutcliffe, Laura; Dormann, Carsten F; Tscharntke, Teja

    2013-01-01

    The aim of this study was to determine the relative effects of landscape-scale management intensity, local management intensity and edge effect on diversity patterns of insect-pollinated vs. non-insect pollinated forbs in meadows and wheat fields. Nine landscapes were selected differing in percent intensively used agricultural area (IAA), each with a pair of organic and conventional winter wheat fields and a pair of organic and conventional meadows. Within fields, forbs were surveyed at the edge and in the interior. Both diversity and cover of forbs were positively affected by organic management in meadows and wheat fields. This effect, however, differed significantly between pollination types for species richness in both agroecosystem types (i.e. wheat fields and meadows) and for cover in meadows. Thus, we show for the first time in a comprehensive analysis that insect-pollinated plants benefit more from organic management than non-insect pollinated plants regardless of agroecosystem type and landscape complexity. These benefits were more pronounced in meadows than wheat fields. Finally, the community composition of insect-pollinated and non-insect-pollinated forbs differed considerably between management types. In summary, our findings in both agroecosystem types indicate that organic management generally supports a higher species richness and cover of insect-pollinated plants, which is likely to be favourable for the density and diversity of bees and other pollinators.

  1. Snowpack and variation in reproductive ecology of a montane ground-nesting passerine, Junco hyemalis

    Science.gov (United States)

    Smith, Kimberly G.; Andersen, Douglas C.

    1985-01-01

    Effects of snow depth and rate of snowmelt on reproduction of a montane ground-nesting passerine were examined in a 5-year study of Dark-eyed Juncos Junco hyemalis in northern Utah, USA. Distribution of clucth sizes differed significantly among years. Although most clutches contained four eggs, 3-egg clutches, due primarily to second nestings, were more common during a year of early snowmelt and 5-egg clutches were most common during two years of late snowmelt. Average clutch size was lowest in an early snowmelt year and average clutch size and date at which meadows became snow-free were significantly positively correlated. Average hatching date of 4-egg clutches was also significantly positively correlated with date at which meadows became snow-free demonstrating that most birds tracked the pattern of snowmelt. Early snowmelt may allow more pairs to attempt second nesting, but late-lying snow causes breeding to be delayed, allowing time for only one nesting attempt. During this delay, female juncos continue to feed and some may gain enough reserves to produce larger clutches, accounting for the increase in average clutch size in years of late snowmelt. Three female juncos examined in June 1982, a period of late snowmelt, had significantly more lipid reserves than did six males collected at the same time, suggesting that females are not physiologically stressed while awaiting snowmelt. By tracking snowmelt patterns, juncos synchronize production of young with peak summer insect abundance and potentially decrease risk of predation. Snow depth and rate of snowmelt are thus proximate environmental factors that may influence the reproductive ecology of ground-nesting passerines.

  2. L'Anse Aux Meadows, Newfoundland

    Science.gov (United States)

    2008-01-01

    L'Anse aux Meadows is a site on the northernmost tip of the island of Newfoundland, located in the Province of Newfoundland and Labrador, Canada, where the remains of a Viking village were discovered in 1960 by the Norwegians Helge and Anne Ingstad. The only authenticated Viking settlement in North America outside Greenland, it was the site of a multi-year archaeological dig that found dwellings, tools and implements that verified its time frame. The settlement, dating more than five hundred years before Christopher Columbus, contains the earliest European structures in North America. Named a World Heritage site by UNESCO, it is thought by many to be the semi-legendary 'Vinland' settlement of explorer Leif Ericson around AD 1000. The settlement at L'Anse aux Meadows consisted of at least eight buildings, including a forge and smelter, and a lumber yard that supported a shipyard. The largest house measured 28.8 by 15.6 m and consisted of several rooms. Sewing and knitting tools found at the site indicate women were present at L'Anse aux Meadows The image was acquired on September 14, 2007, covers an area of 14.2 x 14.6 km, and is located at 51.5 degrees north latitude, 55.6 degrees west longitude. The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate.

  3. Habitat characteristics provide insights of carbon storage in seagrass meadows

    KAUST Repository

    Mazarrasa, Inés

    2018-02-17

    Seagrass meadows provide multiple ecosystem services, yet they are among the most threatened ecosystems on earth. Because of their role as carbon sinks, protection and restoration of seagrass meadows contribute to climate change mitigation. Blue Carbon strategies aim to enhance CO2 sequestration and avoid greenhouse gasses emissions through the management of coastal vegetated ecosystems, including seagrass meadows. The implementation of Blue Carbon strategies requires a good understanding of the habitat characteristics that influence Corg sequestration. Here, we review the existing knowledge on Blue Carbon research in seagrass meadows to identify the key habitat characteristics that influence Corg sequestration in seagrass meadows, those factors that threaten this function and those with unclear effects. We demonstrate that not all seagrass habitats have the same potential, identify research priorities and describe the implications of the results found for the implementation and development of efficient Blue Carbon strategies based on seagrass meadows.

  4. Behaviour of radionuclides in meadows and efficiency of countermeasures

    International Nuclear Information System (INIS)

    Sanzharova, N.I.; Fesenko, S.V.; Kotik, V.A.; Spiridonov, S.I.

    1996-01-01

    The behaviour of radionuclides and the efficiency of countermeasures were dependent on meadow type. The migration of 137 Cs proceeds much more slowly in the soil profile on dry meadows than on peatlands and flooded land. The half-life of 137 Cs in the root zone changes from 10 to 25 years. The highest transfer factors in grasslands are obtained for peaty lands and flooded meadows, and minimal ones for dry meadows. The first half-life of 137 Cs transfer to plants changes from 2.0 to 2.2 years and the second (slower) half-life changes from 4.0 to 12 years for different meadow types. The countermeasure efficiency in meadows varied from 1.2 to 10.0. (Author)

  5. Habitat characteristics provide insights of carbon storage in seagrass meadows.

    Science.gov (United States)

    Mazarrasa, Inés; Samper-Villarreal, Jimena; Serrano, Oscar; Lavery, Paul S; Lovelock, Catherine E; Marbà, Núria; Duarte, Carlos M; Cortés, Jorge

    2018-02-16

    Seagrass meadows provide multiple ecosystem services, yet they are among the most threatened ecosystems on earth. Because of their role as carbon sinks, protection and restoration of seagrass meadows contribute to climate change mitigation. Blue Carbon strategies aim to enhance CO 2 sequestration and avoid greenhouse gasses emissions through the management of coastal vegetated ecosystems, including seagrass meadows. The implementation of Blue Carbon strategies requires a good understanding of the habitat characteristics that influence C org sequestration. Here, we review the existing knowledge on Blue Carbon research in seagrass meadows to identify the key habitat characteristics that influence C org sequestration in seagrass meadows, those factors that threaten this function and those with unclear effects. We demonstrate that not all seagrass habitats have the same potential, identify research priorities and describe the implications of the results found for the implementation and development of efficient Blue Carbon strategies based on seagrass meadows. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Preliminary analysis of productivity of fruiting fungi on Strzeleckie meadows

    Directory of Open Access Journals (Sweden)

    Barbara Sadowska

    2014-11-01

    Full Text Available Analysis demonstrated that the fresh ahd dry weight as well as the ash content of fungal fruit bodies collected on a forest-surrounded unmown meadow (Stellario-Deschampsietum Freitag 1957 and Caricetum elatae W.Koch 1926 were lower than the same values for a plot of exploited mown meadow and higher than on an exploited unmown meadow (Arrhenatheretum medioeuropaeum (Br.-Bl. Oberd. 1952.

  7. Circumscribing campo rupestre – megadiverse Brazilian rocky montane savanas

    Directory of Open Access Journals (Sweden)

    RJV. Alves

    Full Text Available Currently campo rupestre (CR is a name accepted and used internationally by botanists, zoologists, and other naturalists, usually applied to a very specific ecosystem, despite the lack of a consensual published circumscription. We present a tentative geographic circumscription of the term, combining data on climate, geology, geomorphology, soil, flora, fauna and vegetation. The circumscription of campo rupestre proposed herein is based on the following premises: (1 the classification of vegetation is not an exact science, and it is difficult to attain a high degree of consensus to the circumscription of vegetation names; (2 despite this, vegetation classification is useful for conservation and management. It is thus desirable to circumscribe vegetation types with the greatest attainable precision; (3 there is a need to preserve all montane and rocky vegetation types, regardless of classification, biome, etc; (4 the CRs are formed by a complex mosaic of vegetation types including rock-dwelling, psammophilous, aquatic, epiphytic, and penumbral plant communities. Campos rupestres stricto sensu are a Neotropical, azonal vegetation complex endemic to Brazil, forming a mosaic of rocky mountaintop “archipelagos” inserted within a matrix of zonal vegetation, mainly in the Cerrado and Caatinga provinces of the Brazilian Shield (southeastern, northeastern and central-western regions, occurring mainly above 900 m asl. up to altitudes exceeding 2000 m, having measured annual precipitation between 800 and 1500 mm, and an arid season of two to five months.

  8. Circumscribing campo rupestre - megadiverse Brazilian rocky montane savanas.

    Science.gov (United States)

    Alves, R J V; Silva, N G; Oliveira, J A; Medeiros, D

    2014-05-01

    Currently campo rupestre (CR) is a name accepted and used internationally by botanists, zoologists, and other naturalists, usually applied to a very specific ecosystem, despite the lack of a consensual published circumscription. We present a tentative geographic circumscription of the term, combining data on climate, geology, geomorphology, soil, flora, fauna and vegetation. The circumscription of campo rupestre proposed herein is based on the following premises: (1) the classification of vegetation is not an exact science, and it is difficult to attain a high degree of consensus to the circumscription of vegetation names; (2) despite this, vegetation classification is useful for conservation and management. It is thus desirable to circumscribe vegetation types with the greatest attainable precision; (3) there is a need to preserve all montane and rocky vegetation types, regardless of classification, biome, etc; (4) the CRs are formed by a complex mosaic of vegetation types including rock-dwelling, psammophilous, aquatic, epiphytic, and penumbral plant communities. Campos rupestres stricto sensu are a Neotropical, azonal vegetation complex endemic to Brazil, forming a mosaic of rocky mountaintop "archipelagos" inserted within a matrix of zonal vegetation, mainly in the Cerrado and Caatinga provinces of the Brazilian Shield (southeastern, northeastern and central-western regions), occurring mainly above 900 m asl. up to altitudes exceeding 2000 m, having measured annual precipitation between 800 and 1500 mm, and an arid season of two to five months.

  9. Radionuclide transfer to meadow vegetation

    International Nuclear Information System (INIS)

    Goncharova, N.; Matsko, N.; Zhebrakova, I.; Montik, T.

    1999-01-01

    In the paper results of radioecological monitoring of natural plant populations in the 30 km zone of the Chernobyl Nuclear Power Plant (Polesky State Radioecological Reserve) during the period from 1987 to 1998 are presented. The level of radiation background in experimental areas varied from 0.1 to 30 mR/h that correspond to the total soil activity of 300-24000 kBq/m 2 (for May 1997). Monitoring was carried out including the radionuclide migration in natural plant complexes and transfer of 137 Cs between some plant organs. Refs. 3 (author)

  10. Meadow contraction and extinction debt in meadow plants and moths in the Western Cascades

    Science.gov (United States)

    Meadows in the western Cascades have contracted and fragmented by approximately 50% in the past 60 years. These habitats occupy only about 5% of the landscape of the western Cascades but are important for the preservation of biodiversity and rare species. This habitat loss and ...

  11. Response of mountain meadows to grazing by recreational pack stock

    Science.gov (United States)

    Cole, David N.; Van Wagtendonk, Jan W.; McClaran, Mitchel P.; Moore, Peggy E.; McDougald, Neil K.

    2004-01-01

    Effects of recreational pack stock grazing on mountain meadows in Yosemite National Park were assessed in a 5-year study. Yosemite is a designated wilderness, to be managed such that its natural conditions are preserved. Studies were conducted in 3 characteristic meadow types: shorthair sedge (Carex filifolia Nutt.), Brewer's reed grass (Calamagrostis breweri Thurber), and tufted hairgrass [Deschampsia cespitosa (L.) Beauv.]. Horses and mules grazed experimental plots at intensities of 15 to 69% utilization for 4 seasons. In all 3 meadows, grazing caused decreases in productivity. The mean reduction after 4 years of grazing was 18% in the shorthair sedge meadow, 17% in the Brewer's reed grass meadow, and 22% in the tufted hairgrass meadow. Grazing also caused shifts in basal groundcover (usually a reduction in vegetation cover and increase in bare soil cover), and changes in species composition. Productivity and vegetation cover decreased as percent utilization increased, while bare soil cover increased as utilization increased. Changes in species composition were less predictably related to differences in grazing intensity. Passive management of grazing is insufficient in wilderness areas that are regularly used by groups with recreational stock. Wilderness managers need to monitor meadow conditions and the grazing intensities that occur. Our study suggests that biomass and ground cover are more sensitive indicators of grazing impact than species composition. Managers must make decisions about maximum acceptable levels of grazing impact and then develop guidelines for maximum use levels, based on data such as ours that relates grazing intensity to meadow response.

  12. Division by zero in non-involutive meadows

    NARCIS (Netherlands)

    Bergstra, J.A.; Middelburg, C.A.

    2015-01-01

    Meadows have been proposed as alternatives for fields with a purely equational axiomatization. At the basis of meadows lies the decision to make the multiplicative inverse operation total by imposing that the multiplicative inverse of zero is zero. Thus, the multiplicative inverse operation of a

  13. GEOMORPHIC CONTROLS ON MEADOW ECOSYSTEMS IN THE CENTRAL GREAT BASIN

    Science.gov (United States)

    Wet meadows, riparian corridor phreatophyte assemblages, and high-altitude spring-fed aspen meadows comprise a very small percentage of the total landscape of the mountain ranges in the central Great Basin however, they represent important ecological environments. We have used s...

  14. Hydrology of Dutch Cirsio-Molinietum meadows : Prospects for restoration

    NARCIS (Netherlands)

    Jansen, A. J. M.; Grootjans, A. P.; Jalink, M. H.; Bakker, J.P.

    . Fen meadows (Cirsio dissecti-Molinietum) are seriously threatened by desiccation, acidification and eutro-phication. In The Netherlands several projects were launched to restore damaged fen meadows. This review describes how successes and failures of these restoration projects depend on

  15. Response of mountain meadows to grazing by recreational pack stock

    Science.gov (United States)

    David N. Cole; Jan W. van Wagtendonk; Mitchel P. McClaran; Peggy E. Moore; Neil K. McDougald

    2004-01-01

    Effects of recreational pack stock grazing on mountain meadows in Yosemite National Park were assessed in a 5-year study. Yosemite is a designated wilderness, to be managed such that its natural conditions are preserved. Studies were conducted in 3 characteristic meadow types: shorthair sedge (Carex filifolia Nutt.), Brewer’s reed grass (...

  16. The effect of management practice of montane meadows in the Bohemian Forest on selected soil biological and chemical properties

    Czech Academy of Sciences Publication Activity Database

    Šimek, Miloslav; Šantrůčková, Hana; Uhlířová, Eva; Záhora, J.; Picek, T.; Brychtová, L.; Šetlík, J.

    2001-01-01

    Roč. 7, - (2001), s. 69-78 ISSN 1211-7420 R&D Projects: GA ČR GA206/99/1410 Institutional research plan: CEZ:AV0Z6066911 Keywords : microbial community * grassland * mulching Subject RIV: EH - Ecology, Behaviour

  17. Photosynthetic activity buffers ocean acidification in seagrass meadows

    Science.gov (United States)

    Hendriks, I. E.; Olsen, Y. S.; Ramajo, L.; Basso, L.; Steckbauer, A.; Moore, T. S.; Howard, J.; Duarte, C. M.

    2014-01-01

    Macrophytes growing in shallow coastal zones characterised by intense metabolic activity have the capacity to modify pH within their canopy and beyond. We observed diel pH changes in shallow (5-12 m) seagrass (Posidonia oceanica) meadows spanning 0.06 pH units in September to 0.24 units in June. The carbonate system (pH, DIC, and aragonite saturation state (ΩAr)) and O2 within the meadows displayed strong diel variability driven by primary productivity, and changes in chemistry were related to structural parameters of the meadow, in particular, the leaf surface area available for photosynthesis (LAI). LAI was positively correlated to mean, max and range pHNBS and max and range ΩAr. In June, vertical mixing (as Turbulent Kinetic Energy) influenced max and min ΩAr, while in September there was no effect of hydrodynamics on the carbonate system within the canopy. Max and range ΩAr within the meadow showed a positive trend with the calcium carbonate load of the leaves, pointing to a possible link between structural parameters, ΩAr and carbonate deposition. Calcifying organisms, e.g. epiphytes with carbonate skeletons, may benefit from the modification of the carbonate system by the meadow. There is, however, concern for the ability of seagrasses to provide modifications of similar importance in the future. The predicted decline of seagrass meadows may alter the scope for alteration of pH within a seagrass meadow and in the water column above the meadow, particularly if shoot density and biomass decline, on which LAI is based. Organisms associated with seagrass communities may therefore suffer from the loss of pH buffering capacity in degraded meadows.

  18. Is forage productivity of meadows influenced by the afforestation of upstream hillsides? A study in NW Patagonia

    Energy Technology Data Exchange (ETDEWEB)

    Weigandt, M.; Gyenge, J.; Fernandez, M. E.; Varela, S.; Schlichter, T.

    2011-07-01

    Meadows are important reserves of water, with a key role in the maintenance of the biodiversity and productivity of ecosystems. In Patagonia, Argentina, afforestation with fast-growing exotic conifers has slowly but continuously increased over recent decades; though unfortunately, knowledge of the effects of afforestation on water resources remains scarce, with no information at all related to its impact on water dynamics and productivity of meadows located down slope to it. The effects of Pinus ponderosa afforestation on water dynamics (soil moisture contents and groundwater level) and productivity (aboveground forage productivity) of Northwest Patagonia meadows under xeric and humid conditions were analyzed. In the humid meadow, gravimetric soil water content, groundwater level and forage productivity were similar down slope of forested and non-forested slopes, with a trend towards higher forage productivity on the forested slope. In the xeric meadow, gravimetric soil water content was always higher down slope of the non-forested slope, with no difference in groundwater level between treatments. Forage productivity was statistically similar between situations (down slope of forested and non-forested slopes), with a trend towards higher productivity in the zone with higher soil water content. The main difference in the latter was related to differences in soil texture between zones. These results suggest that coniferous plantations located upstream of this type of meadow do not produce a direct effect on its aboveground forage productivity. These systems have high complexity linked to precipitation, geomorphology and previous history of land use, which determine primarily soil water dynamics and consequently, forage productivity. (Author) 42 refs.

  19. Lower Red River Meadow Stream Restoration Project

    International Nuclear Information System (INIS)

    1996-05-01

    As part of a continuing effort to restore anadromous fish populations in the South Fork Clearwater River basin of Idaho, Bonneville Power Administration (BPA) proposes to fund the Lower Red River Meadow Restoration Project (Project). The Project is a cooperative effort with the Idaho Soil and Water Conservation District, Nez Perce National Forest, Idaho Department of Fish and Game (IDFG), and the Nez Perce Tribe of Idaho. The proposed action would allow the sponsors to perform stream bank stabilization, aquatic and riparian habitat improvement activities on IDFG's Red River Management Area and to secure long-term conservation contracts or agreements for conducting streambank and habitat improvement activities with participating private landowners located in the Idaho County, Idaho, study area. This preliminary Environmental Assessment (EA) examines the potential environmental effects of stabilizing the stream channel, restoring juvenile fish rearing habitat and reestablishing a riparian shrub community along the stream

  20. Sensitivity of permanent meadows areas. Preliminary report

    International Nuclear Information System (INIS)

    Pourcelot, L.

    2006-01-01

    The objective of this work proposed in the framework of the S.E.N.S.I.B. project on the permanent meadows areas is to compare the sensitivity of these surfaces and cheese maker sector which are associated with them, and to identify the processes which determine this sensitivity. The realization of this objective will lean on certain data of activities acquired recently by the I.R.S.N. (compartments: soils, herb, milk and cheese), as well as on new measures, on three sites: Saint-Laurent-de-Geris ( West), Beaune-Le-Froid ( center), and Massif of Jura (East). Two scales of transfers observation and sensitivity are retained. In a first time, the sensitivity of meadows areas will studied at the regional scale, from data acquired in the Massif du Jura ( between 300 and 1200 metres up). In a second time, a study will allow to compare the sensitivity of three areas retained (West, Center, East) at the national scale. The expertise will be focused on the factors of sensitivity of the transfer soil-herb and the factors of sensitivity bound to the cheese makers sectors. The data of the already available zones of study create strong variabilities of the rates of 137 Cs transfer in the interfaces soil / herb and herb / milk, letting suppose that the nature of soils, the quantity and the quality of food ingested by the cattle constitutes dominating factors of sensitivity. Besides, the size of the basin of milk collection, extremely variable from a site of study in the other one, has to influence the contamination of cheeses and as such, it establishes an important factor of sensitivity of the cheese makers sector. (N.C.)

  1. Scrub-shrub bird habitat associations at multiple spatial scales in beaver meadows in Massachusetts

    Science.gov (United States)

    Chandler, R.B.; King, D.I.; DeStefano, S.

    2009-01-01

    Most scrub-shrub bird species are declining in the northeastern United States, and these declines are largely attributed to regional declines in habitat availability. American Beaver (Castor canadensis; hereafter “beaver”) populations have been increasing in the Northeast in recent decades, and beavers create scrub-shrub habitat through their dam-building and foraging activities. Few systematic studies have been conducted on the value of beaver-modified habitats for scrub-shrub birds, and these data are important for understanding habitat selection of scrub-shrub birds as well as for assessing regional habitat availability for these species. We conducted surveys in 37 beaver meadows in a 2,800-km2 study area in western Massachusetts during 2005 and 2006 to determine the extent to which these beaver-modified habitats are used by scrub-shrub birds, as well as the characteristics of beaver meadows most closely related to bird use. We modeled bird abundance in relation to microhabitat-, patch-, and landscape-context variables while adjusting for survey-specific covariates affecting detectability using N-mixture models. We found that scrub-shrub birds of regional conservation concern occupied these sites and that birds responded differently to microhabitat, patch, and landscape characteristics of beaver meadows. Generally, scrub-shrub birds increased in abundance along a gradient of increasing vegetation complexity, and three species were positively related to patch size. We conclude that these habitats can potentially play an important role in regional conservation of scrub-shrub birds and recommend that conservation priority be given to larger beaver meadows with diverse vegetation structure and composition.

  2. Habitat characteristics provide insights of carbon storage in seagrass meadows

    KAUST Repository

    Mazarrasa, Iné s; Samper-Villarreal, Jimena; Serrano, Oscar; Lavery, Paul S.; Lovelock, Catherine E.; Marbà , Nú ria; Duarte, Carlos M.; Corté s, Jorge

    2018-01-01

    Carbon strategies aim to enhance CO2 sequestration and avoid greenhouse gasses emissions through the management of coastal vegetated ecosystems, including seagrass meadows. The implementation of Blue Carbon strategies requires a good understanding

  3. Probability functions in the context of signed involutive meadows

    NARCIS (Netherlands)

    Bergstra, J.A.; Ponse, A.

    2016-01-01

    The Kolmogorov axioms for probability functions are placed in the context of signed meadows. A completeness theorem is stated and proven for the resulting equational theory of probability calculus. Elementary definitions of probability theory are restated in this framework.

  4. Key biogeochemical factors affecting soil carbon storage in Posidonia meadows

    KAUST Repository

    Serrano, Oscar

    2016-08-15

    Biotic and abiotic factors influence the accumulation of organic carbon (C-org) in seagrass ecosystems. We surveyed Posidonia sinuosa meadows growing in different water depths to assess the variability in the sources, stocks and accumulation rates of Corg. We show that over the last 500 years, P. sinuosa meadows closer to the upper limit of distribution (at 2-4 m depth) accumulated 3- to 4-fold higher C-org stocks (averaging 6.3 kg C-org m(-2) at 3- to 4-fold higher rates (12.8 gC(org) m(-2) yr(-1) ) compared to meadows closer to the deep limits of distribution (at 6-8 m depth; 1.8 kg C-org m(-2) and 3.6 g C-org m(-2) yr(-1) . In shallower meadows, C-org stocks were mostly derived from seagrass detritus (88% in average) compared to meadows closer to the deep limit of distribution (45% on average). In addition, soil accumulation rates and fine-grained sediment content (< 0.125 mm) in shallower meadows (2.0 mm yr(-1) and 9 %, respectively) were approximately 2-fold higher than in deeper meadows (1.2 mm yr(-1) and 5 %, respectively). The C-org stocks and accumulation rates accumulated over the last 500 years in bare sediments (0.6 kg C-org m(-2) and 1.2 g C-org m(-2) yr(-1)were 3- to 11-fold lower than in P. sinuosa meadows, while fine-grained sediment content (1 %) and seagrass detritus contribution to the Corg pool (20 %) were 8- and 3-fold lower than in Posidonia meadows, respectively. The patterns found support the hypothesis that Corg storage in seagrass soils is influenced by interactions of biological (e.g., meadow productivity, cover and density), chemical (e.g., recalcitrance of Corg stocks) and physical (e.g., hydrodynamic energy and soil accumulation rates) factors within the meadow. We conclude that there is a need to improve global estimates of seagrass carbon storage accounting for biogeochemical factors driving variability within habitats.

  5. Ecological transition in Arizona's subalpine and montane grasslands

    Science.gov (United States)

    Michael R. White

    2000-01-01

    Important components of Southwest forest ecosystem are subalpine and montane grassland communities, Grassland communities provide habitat diversity for wildlife, forage for domestic livestock and wildlife, and contribute to the visual quality of an area. The objectives of this research were to determine if: 1) vegetation attributes and soil-surface cover variables of...

  6. Forest health in Canada, Montane cordillera ecozone 2003

    Energy Technology Data Exchange (ETDEWEB)

    Allen, E.; Garbutt, R.; Hirvonen, H.; Pinnell, H.

    2004-07-01

    This paper describes the key forest health issues affecting the 6 main forest types in Canada's Montane Cordillera ecozone in the central interior of British Columbia and the Alberta Foothills. In order to protect and conserve biological diversity, the Canadian Council of Forest Ministers adopted national criteria to measure sustainable forest management. This report describes the Montane Cordillera landscape conditions, pre-industrial ecological influences, current ecological influences, and the impact of invasive alien insects and diseases on the diversity of tree species. Pine forests in the Montane Cordillera ecozone are threatened by the mountain pine beetle. Fire suppression has also resulted in ecological changes to forests in the Montane Cordillera, including an increase in Douglas-firs, gradual replacement of Lodgepole pine forests, and reduced health of Ponderosa pine ecosystems. Alien insects are being monitored by provincial forestry agencies through annual surveys. They are also being controlled through localized treatment programs. The impact of land use practices such as forest harvesting on forest structure and composition was also addressed. It was noted that the unrestricted movement of wood and forestry products also increases the threat of invasive alien diseases and insects. The trees in this ecozone have not been damaged by air pollution. refs., tabs., figs.

  7. Structure and Regeneration Status of Gedo Dry Evergreen Montane ...

    African Journals Online (AJOL)

    This study was conducted on Gedo Dry Evergreen Montane Forest in West Shewa Zone of Oromia National Regional State, 182-196 km west of Addis Ababa (Finfinne). The objective of the study was to determine structure and regeneration status of Gedo Forest. All trees and shrubs with Diameter at Breast Height (DBH) ...

  8. The montane forest associated amphibian species of the Taita Hills ...

    African Journals Online (AJOL)

    The montane forest associated amphibian species of the Taita Hills, Kenya. ... They are surrounded by the dry Tsavo plains. ... The biodiversity importance of the Taita Hills lies with the number of endemics per unit of area of remaining forest, ...

  9. Flooding tolerance of four floodplain meadow species depends on age.

    Science.gov (United States)

    Gattringer, Johannes P; Donath, Tobias W; Eckstein, R Lutz; Ludewig, Kristin; Otte, Annette; Harvolk-Schöning, Sarah

    2017-01-01

    Numerous restoration campaigns focused on re-establishing species-rich floodplain meadows of Central Europe, whose species composition is essentially controlled by regular flooding. Climate change predictions expect strong alterations on the discharge regime of Europe's large rivers with little-known consequences on floodplain meadow plants. In this study, we aim to determine the effects of flooding on seedlings of different ages of four typical flood meadow species. To this end, we flooded seedlings of two familial pairs of flood meadow species of wetter and dryer microhabitats for 2 weeks each, starting 2, 4, 6, and 8 weeks after seedling germination, respectively. We show that a 2-week-flooding treatment had a negative effect on performance of seedlings younger than 6 weeks. Summer floods with high floodwater temperatures may have especially detrimental effects on seedlings, which is corroborated by previous findings. As expected, the plants from wet floodplain meadow microhabitats coped better with the flooding treatment than those from dryer microhabitats. In conclusion, our results suggest that restoration measures may perform more successfully if seedlings of restored species are older than the critical age of about 6 weeks before a spring flooding begins. Seasonal flow patterns may influence vegetation dynamics of floodplain meadows and should, therefore, be taken into account when timing future restoration campaigns.

  10. Flooding tolerance of four floodplain meadow species depends on age.

    Directory of Open Access Journals (Sweden)

    Johannes P Gattringer

    Full Text Available Numerous restoration campaigns focused on re-establishing species-rich floodplain meadows of Central Europe, whose species composition is essentially controlled by regular flooding. Climate change predictions expect strong alterations on the discharge regime of Europe's large rivers with little-known consequences on floodplain meadow plants. In this study, we aim to determine the effects of flooding on seedlings of different ages of four typical flood meadow species. To this end, we flooded seedlings of two familial pairs of flood meadow species of wetter and dryer microhabitats for 2 weeks each, starting 2, 4, 6, and 8 weeks after seedling germination, respectively. We show that a 2-week-flooding treatment had a negative effect on performance of seedlings younger than 6 weeks. Summer floods with high floodwater temperatures may have especially detrimental effects on seedlings, which is corroborated by previous findings. As expected, the plants from wet floodplain meadow microhabitats coped better with the flooding treatment than those from dryer microhabitats. In conclusion, our results suggest that restoration measures may perform more successfully if seedlings of restored species are older than the critical age of about 6 weeks before a spring flooding begins. Seasonal flow patterns may influence vegetation dynamics of floodplain meadows and should, therefore, be taken into account when timing future restoration campaigns.

  11. Projecting the Hydrologic Impacts of Climate Change on Montane Wetlands.

    Science.gov (United States)

    Lee, Se-Yeun; Ryan, Maureen E; Hamlet, Alan F; Palen, Wendy J; Lawler, Joshua J; Halabisky, Meghan

    2015-01-01

    Wetlands are globally important ecosystems that provide critical services for natural communities and human society. Montane wetland ecosystems are expected to be among the most sensitive to changing climate, as their persistence depends on factors directly influenced by climate (e.g. precipitation, snowpack, evaporation). Despite their importance and climate sensitivity, wetlands tend to be understudied due to a lack of tools and data relative to what is available for other ecosystem types. Here, we develop and demonstrate a new method for projecting climate-induced hydrologic changes in montane wetlands. Using observed wetland water levels and soil moisture simulated by the physically based Variable Infiltration Capacity (VIC) hydrologic model, we developed site-specific regression models relating soil moisture to observed wetland water levels to simulate the hydrologic behavior of four types of montane wetlands (ephemeral, intermediate, perennial, permanent wetlands) in the U. S. Pacific Northwest. The hybrid models captured observed wetland dynamics in many cases, though were less robust in others. We then used these models to a) hindcast historical wetland behavior in response to observed climate variability (1916-2010 or later) and classify wetland types, and b) project the impacts of climate change on montane wetlands using global climate model scenarios for the 2040s and 2080s (A1B emissions scenario). These future projections show that climate-induced changes to key driving variables (reduced snowpack, higher evapotranspiration, extended summer drought) will result in earlier and faster drawdown in Pacific Northwest montane wetlands, leading to systematic reductions in water levels, shortened wetland hydroperiods, and increased probability of drying. Intermediate hydroperiod wetlands are projected to experience the greatest changes. For the 2080s scenario, widespread conversion of intermediate wetlands to fast-drying ephemeral wetlands will likely reduce

  12. Projecting the Hydrologic Impacts of Climate Change on Montane Wetlands

    Science.gov (United States)

    Hamlet, Alan F.; Palen, Wendy J.; Lawler, Joshua J.; Halabisky, Meghan

    2015-01-01

    Wetlands are globally important ecosystems that provide critical services for natural communities and human society. Montane wetland ecosystems are expected to be among the most sensitive to changing climate, as their persistence depends on factors directly influenced by climate (e.g. precipitation, snowpack, evaporation). Despite their importance and climate sensitivity, wetlands tend to be understudied due to a lack of tools and data relative to what is available for other ecosystem types. Here, we develop and demonstrate a new method for projecting climate-induced hydrologic changes in montane wetlands. Using observed wetland water levels and soil moisture simulated by the physically based Variable Infiltration Capacity (VIC) hydrologic model, we developed site-specific regression models relating soil moisture to observed wetland water levels to simulate the hydrologic behavior of four types of montane wetlands (ephemeral, intermediate, perennial, permanent wetlands) in the U. S. Pacific Northwest. The hybrid models captured observed wetland dynamics in many cases, though were less robust in others. We then used these models to a) hindcast historical wetland behavior in response to observed climate variability (1916–2010 or later) and classify wetland types, and b) project the impacts of climate change on montane wetlands using global climate model scenarios for the 2040s and 2080s (A1B emissions scenario). These future projections show that climate-induced changes to key driving variables (reduced snowpack, higher evapotranspiration, extended summer drought) will result in earlier and faster drawdown in Pacific Northwest montane wetlands, leading to systematic reductions in water levels, shortened wetland hydroperiods, and increased probability of drying. Intermediate hydroperiod wetlands are projected to experience the greatest changes. For the 2080s scenario, widespread conversion of intermediate wetlands to fast-drying ephemeral wetlands will likely reduce

  13. Nitrogen fixation in Red Sea seagrass meadows

    KAUST Repository

    Abdallah, Malak

    2017-05-01

    Seagrasses are key coastal ecosystems, providing many ecosystem services. Seagrasses increase biodiversity as they provide habitat for a large set of organisms. In addition, their structure provides hiding places to avoid predation. Seagrasses can grow in shallow marine coastal areas, but several factors regulate their growth and distribution. Seagrasses can uptake different kinds of organic and inorganic nutrients through their leaves and roots. Nitrogen and phosphorous are the most important nutrients for seagrass growth. Biological nitrogen fixation is the conversion of atmospheric nitrogen into ammonia by diazotrophic bacteria. This process provides a significant source of nitrogen for seagrass growth. The nitrogen fixation is controlled by the nif genes which are found in diazotrophs. The main goal of the project is to measure nitrogen fixation rates on seagrass sediments, in order to compare among various seagrass species from the Red Sea. Moreover, we will compare the fixing rates of the Vegetated areas with the bare sediments. This project will help to ascertain the role of nitrogen fixing bacteria in the development of seagrass meadows.

  14. Coral Community Structure and Recruitment in Seagrass Meadows

    Directory of Open Access Journals (Sweden)

    Kathryn E. Lohr

    2017-11-01

    Full Text Available Coral communities are increasingly found to populate non-reef habitats prone to high environmental variability. Such sites include seagrass meadows, which are generally not considered optimal habitats for corals as a result of limited suitable substrate for settlement and substantial diel and seasonal fluctuations in physicochemical conditions relative to neighboring reefs. Interest in understanding the ability of corals to persist in non-reef habitats has grown, however little baseline data exists on community structure and recruitment of scleractinian corals in seagrass meadows. To determine how corals populate seagrass meadows, we surveyed the established and recruited coral community over 25 months within seagrass meadows at Little Cayman, Cayman Islands. Simultaneous surveys of established and recruited coral communities at neighboring back-reef sites were conducted for comparison. To fully understand the amount of environmental variability to which corals in each habitat were exposed, we conducted complementary surveys of physicochemical conditions in both seagrass meadows and back-reefs. Despite overall higher variability in physicochemical conditions, particularly pH, compared to the back-reef, 14 coral taxa were capable of inhabiting seagrass meadows, and multiple coral families were also found to recruit to these sites. However, coral cover and species diversity, richness, and evenness were lower at sites within seagrass meadows compared to back-reef sites. Although questions remain regarding the processes governing recruitment, these results provide evidence that seagrass beds can serve as functional habitats for corals despite high levels of environmental variability and suboptimal conditions compared to neighboring reefs.

  15. BIOGEOGRAPHICAL IMPLICATIONS OF SOME PLANT SPECIES FROM A TROPICAL MONTANE RAIN FOREST IN SOUTHERN YUNNAN

    Institute of Scientific and Technical Information of China (English)

    ZHU Hua

    2004-01-01

    A pristine montane rain forest was recently discovered from Mengsong of Xishuangbanna in the southern Yunnan.It attracts botanists that many primitive plant taxa across various life forms were co-existed in the montane rain forest.In order to know the biogeography of the montane rain forest,distribution patterns of some species of biogeographical importance from the montane forest were enumerated and their biogeographical implications were discussed with geological explanation.It was concluded that the montane rain forest in the southern Yunnan has strong affinity to montane rain forests in Sumatra or Southeast Asia in broad sense.It was tentatively suggested that Sumatra could be once connected to Myanmar and drifted away due to northward movement of continental Asia by bumping of India plate.

  16. Impact of mooring activities on carbon stocks in seagrass meadows

    KAUST Repository

    Serrano, O.; Ruhon, R.; Lavery, P. S.; Kendrick, G. A.; Hickey, S.; Masqué , P.; Arias-Ortiz, A.; Steven, A.; Duarte, Carlos M.

    2016-01-01

    Boating activities are one of the causes that threaten seagrass meadows and the ecosystem services they provide. Mechanical destruction of seagrass habitats may also trigger the erosion of sedimentary organic carbon (Corg) stocks, which may contribute to increasing atmospheric CO2. This study presents the first estimates of loss of Corg stocks in seagrass meadows due to mooring activities in Rottnest Island, Western Australia. Sediment cores were sampled from seagrass meadows and from bare but previously vegetated sediments underneath moorings. The Corg stores have been compromised by the mooring deployment from 1930s onwards, which involved both the erosion of existing sedimentary Corg stores and the lack of further accumulation of Corg. On average, undisturbed meadows had accumulated ~6.4 Kg Corg m−2 in the upper 50 cm-thick deposits at a rate of 34 g Corg m−2 yr−1. The comparison of Corg stores between meadows and mooring scars allows us to estimate a loss of 4.8 kg Corg m−2 in the 50 cm-thick deposits accumulated over ca. 200 yr as a result of mooring deployments. These results provide key data for the implementation of Corg storage credit offset policies to avoid the conversion of seagrass ecosystems and contribute to their preservation.

  17. Impact of mooring activities on carbon stocks in seagrass meadows

    KAUST Repository

    Serrano, O.

    2016-03-16

    Boating activities are one of the causes that threaten seagrass meadows and the ecosystem services they provide. Mechanical destruction of seagrass habitats may also trigger the erosion of sedimentary organic carbon (Corg) stocks, which may contribute to increasing atmospheric CO2. This study presents the first estimates of loss of Corg stocks in seagrass meadows due to mooring activities in Rottnest Island, Western Australia. Sediment cores were sampled from seagrass meadows and from bare but previously vegetated sediments underneath moorings. The Corg stores have been compromised by the mooring deployment from 1930s onwards, which involved both the erosion of existing sedimentary Corg stores and the lack of further accumulation of Corg. On average, undisturbed meadows had accumulated ~6.4 Kg Corg m−2 in the upper 50 cm-thick deposits at a rate of 34 g Corg m−2 yr−1. The comparison of Corg stores between meadows and mooring scars allows us to estimate a loss of 4.8 kg Corg m−2 in the 50 cm-thick deposits accumulated over ca. 200 yr as a result of mooring deployments. These results provide key data for the implementation of Corg storage credit offset policies to avoid the conversion of seagrass ecosystems and contribute to their preservation.

  18. Seagrasses under threat: Understanding the resilience of temperate seagrass meadows in a changing environment

    NARCIS (Netherlands)

    Soissons, L.M.

    2017-01-01

    Despite being highly valuable ecosystems, seagrass meadows are threatened worldwide, mostly by human activities. In order to preserve seagrass meadows from collapse, we need to better understand their resilience in a changing environment. By means of various

  19. Birds, Montane forest, State of Rio de Janeiro, Southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Foster, A.

    2009-01-01

    Full Text Available Field surveys in montane Atlantic forest of Rio de Janeiro state, Brazil, provided a list of 82 bird species in four sitesvisited. Our protocol relied on standardized use of mist nets and observations. The birds recorded include 40 Atlanticforest endemics, three globally and two nationally Vulnerable species, and two regionally Endangered species. Data onspecies elevation are included and discussed. This work enhances baseline knowledge of these species to assist futurestudies in these poorly understood, but biologically important areas.

  20. Predictors of breeding site occupancy by amphibians in montane landscapes

    Science.gov (United States)

    Groff, Luke A.; Loftin, Cynthia S.; Calhoun, Aram J.K.

    2017-01-01

    Ecological relationships and processes vary across species’ geographic distributions, life stages and spatial, and temporal scales. Montane landscapes are characterized by low wetland densities, rugged topographies, and cold climates. Consequently, aquatic-dependent and low-vagility ectothermic species (e.g., pool-breeding amphibians) may exhibit unique ecological associations in montane landscapes. We evaluated the relative importance of breeding- and landscape-scale features associated with spotted salamander (Ambystoma maculatum) and wood frog (Lithobates sylvaticus) wetland occupancy in Maine's Upper Montane-Alpine Zone ecoregion, and we determined whether models performed better when the inclusive landscape-scale covariates were estimated with topography-weighted or circular buffers. We surveyed 135 potential breeding sites during May 2013–June 2014 and evaluated environmental relationships with multi-season implicit dynamics occupancy models. Breeding site occupancy by both species was influenced solely by breeding-scale habitat features. Spotted salamander occupancy probabilities increased with previous or current beaver (Castor canadensis) presence, and models generally were better supported when the inclusive landscape-scale covariates were estimated with topography-weighted rather than circular buffers. Wood frog occupancy probabilities increased with site area and percent shallows, but neither buffer type was better supported than the other. Model rank order and support varied between buffer types, but model inferences did not. Our results suggest pool-breeding amphibian conservation in montane Maine include measures to maintain beaver populations and large wetlands with proportionally large areas of shallows ≤1-m deep. Inconsistencies between our study and previous studies substantiate the value of region-specific research for augmenting species’ conservation management plans and suggest the application of out-of-region inferences may promote

  1. Export from Seagrass Meadows Contributes to Marine Carbon Sequestration

    KAUST Repository

    Duarte, Carlos M.; Krause-Jensen, Dorte

    2017-01-01

    Seagrasses export a substantial portion of their primary production, both in particulate and dissolved organic form, but the fate of this export production remains unaccounted for in terms of seagrass carbon sequestration. Here we review available evidence on the fate of seagrass carbon export to conclude that this represents a significant contribution to carbon sequestration, both in sediments outside seagrass meadows and in the deep sea. The evidence presented implies that the contribution of seagrass meadows to carbon sequestration has been underestimated by only including carbon burial within seagrass sediments.

  2. Export from Seagrass Meadows Contributes to Marine Carbon Sequestration

    KAUST Repository

    Duarte, Carlos M.

    2017-01-17

    Seagrasses export a substantial portion of their primary production, both in particulate and dissolved organic form, but the fate of this export production remains unaccounted for in terms of seagrass carbon sequestration. Here we review available evidence on the fate of seagrass carbon export to conclude that this represents a significant contribution to carbon sequestration, both in sediments outside seagrass meadows and in the deep sea. The evidence presented implies that the contribution of seagrass meadows to carbon sequestration has been underestimated by only including carbon burial within seagrass sediments.

  3. Spatial assessment of intertidal seagrass meadows using optical imaging systems and a lightweight drone

    Science.gov (United States)

    Duffy, James P.; Pratt, Laura; Anderson, Karen; Land, Peter E.; Shutler, Jamie D.

    2018-01-01

    Seagrass ecosystems are highly sensitive to environmental change. They are also in global decline and under threat from a variety of anthropogenic factors. There is now an urgency to establish robust monitoring methodologies so that changes in seagrass abundance and distribution in these sensitive coastal environments can be understood. Typical monitoring approaches have included remote sensing from satellites and airborne platforms, ground based ecological surveys and snorkel/scuba surveys. These techniques can suffer from temporal and spatial inconsistency, or are very localised making it hard to assess seagrass meadows in a structured manner. Here we present a novel technique using a lightweight (sub 7 kg) drone and consumer grade cameras to produce very high spatial resolution (∼4 mm pixel-1) mosaics of two intertidal sites in Wales, UK. We present a full data collection methodology followed by a selection of classification techniques to produce coverage estimates at each site. We trialled three classification approaches of varying complexity to investigate and illustrate the differing performance and capabilities of each. Our results show that unsupervised classifications perform better than object-based methods in classifying seagrass cover. We also found that the more sparsely vegetated of the two meadows studied was more accurately classified - it had lower root mean squared deviation (RMSD) between observed and classified coverage (9-9.5%) compared to a more densely vegetated meadow (RMSD 16-22%). Furthermore, we examine the potential to detect other biotic features, finding that lugworm mounds can be detected visually at coarser resolutions such as 43 mm pixel-1, whereas smaller features such as cockle shells within seagrass require finer grained data (<17 mm pixel-1).

  4. Effects of fish farm waste on Posidonia oceanica meadows: Synthesis and provision of monitoring and management tools

    Energy Technology Data Exchange (ETDEWEB)

    Holmer, Marianne [Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M (Denmark)], E-mail: holmer@biology.sdu.dk; Argyrou, Marina [Marine Environment Division, Department of Fisheries and Marine Research, Ministry of Agriculture, Natural Resources and Environment, 101 Bethleem Street, 1416 Nicosia (Cyprus); Dalsgaard, Tage [Department of Marine Ecology, National Environmental Research Institute, Aarhus University, Vejlsovej 25, P.O. Box 314, DK-8600 Silkeborg (Denmark); Danovaro, Roberto [Department of Marine Science, Polytechnic University of Marche, Via Brecce Bianche, 60131 Ancona (Italy); Diaz-Almela, Elena; Duarte, Carlos M. [IMEDEA (CSIC-UIB), Miquel Marques 21, 07190 Esporles (Illes Balears) (Spain); Frederiksen, Morten [Institute of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M (Denmark); Grau, Antoni [Direccio General de Pesca, Conselleria d' Agricultura i Pesca, Govern de les Illes Balears, Foners 10, 07006 Palma de Mallorca (Illes Balears) (Spain); Karakassis, Ioannis [Marine Ecology Laboratory, Biology Department, University of Crete, Heraklion, 71409 Crete (Greece); Marba, Nuria [IMEDEA (CSIC-UIB), Miquel Marques 21, 07190 Esporles (Illes Balears) (Spain); Mirto, Simone [Institute for the Marine Coastal Environment, National Council of Research, Spianata S. Raineri, 86, 98122 Messina (Italy); Perez, Marta [Departament d' Ecologia, Universitat de Barcelona, Av. Diagonal 645, 08028 Barcelona (Spain); Pusceddu, Antonio [Department of Marine Science, Polytechnic University of Marche, Via Brecce Bianche, 60131 Ancona (Italy); Tsapakis, Manolis [Institute of Oceanography, Hellenic Center for Marine Research, P.O. Box 2214, GR 71003 Heraklion, Crete (Greece)

    2008-09-15

    This paper provides a synthesis of the EU project MedVeg addressing the fate of nutrients released from fish farming in the Mediterranean with particular focus on the endemic seagrass Posidonia oceanica habitat. The objectives were to identify the main drivers of seagrass decline linked to fish farming and to provide sensitive indicators of environmental change, which can be used for monitoring purposes. The sedimentation of waste particles in the farm vicinities emerges as the main driver of benthic deterioration, such as accumulation of organic matter, sediment anoxia as well as seagrass decline. The effects of fish farming on P. oceanica meadows are diverse and complex and detected through various metrics and indicators. A safety distance of 400 m is suggested for management of P. oceanica near fish farms followed by establishment of permanent seagrass plots revisited annually for monitoring the health of the meadows.

  5. Effects of fish farm waste on Posidonia oceanica meadows: Synthesis and provision of monitoring and management tools

    International Nuclear Information System (INIS)

    Holmer, Marianne; Argyrou, Marina; Dalsgaard, Tage; Danovaro, Roberto; Diaz-Almela, Elena; Duarte, Carlos M.; Frederiksen, Morten; Grau, Antoni; Karakassis, Ioannis; Marba, Nuria; Mirto, Simone; Perez, Marta; Pusceddu, Antonio; Tsapakis, Manolis

    2008-01-01

    This paper provides a synthesis of the EU project MedVeg addressing the fate of nutrients released from fish farming in the Mediterranean with particular focus on the endemic seagrass Posidonia oceanica habitat. The objectives were to identify the main drivers of seagrass decline linked to fish farming and to provide sensitive indicators of environmental change, which can be used for monitoring purposes. The sedimentation of waste particles in the farm vicinities emerges as the main driver of benthic deterioration, such as accumulation of organic matter, sediment anoxia as well as seagrass decline. The effects of fish farming on P. oceanica meadows are diverse and complex and detected through various metrics and indicators. A safety distance of 400 m is suggested for management of P. oceanica near fish farms followed by establishment of permanent seagrass plots revisited annually for monitoring the health of the meadows

  6. Using GIS technology to analyze and understand wet meadow ecosystems

    Science.gov (United States)

    Joy Rosen; Roy Jemison; David Pawelek; Daniel Neary

    1999-01-01

    A Cibola National Forest wet meadow restoration was implemented as part of the Forest Road 49 enhancement near Grants, New Mexico. An Arc/View 3.0 Geographic Information System (GIS) was used to track the recovery of this ecosystem. Layers on topography, hydrology, vegetation, soils and human alterations were compiled using a GPS and commonly available data....

  7. COENOLOGICAL STATUS OF THE IRIS MEADOWS IN HUNGARY

    Directory of Open Access Journals (Sweden)

    E. SALAMON-ALBERT

    2010-04-01

    Full Text Available Species composition and vegetation structure by association and local diagnostic, constant and dominant species of Iridetum sibiricae was analysed from Hungary adjusting to the evaluation of European vegetation. Classification, ordination and statistical analyses was carried out to characterize and make distinction to some other wet meadow vegetation types. In the association habitat and management dependent subunits were formed.

  8. Restoration of brook valley meadows in the Netherlands

    NARCIS (Netherlands)

    Grootjans, A.P.; Bakker, J.P.; Jansen, A.J.M.; Kemmers, R.H.

    2002-01-01

    Until recently, restoration measures in Dutch brook valley meadows consisted of re-introducing traditional management techniques, such as mowing without fertilisation and low-intensity grazing. In the Netherlands, additional measures, such as rewetting and sod cutting, are now carried out on a large

  9. Effects of phenolic acid structures on meadow hay digestibility

    NARCIS (Netherlands)

    Rodrigues, M.A.M.; Guedes, C.M.; Cone, J.W.; Gelder, van A.H.; Ferreira, L.M.M.; Sequeira, C.A.

    2007-01-01

    The objectives were to evaluate effects of phenolic acid content and composition on the digestibility of six meadow hays from Northern Portugal. Digestibility was assessed by gas production, in vitro and in situ degradation methods. Four cows fed diets at energy maintenance were used for in situ

  10. Prospects for fen meadow restoration on severely degraded fens

    NARCIS (Netherlands)

    Klimkowska, Agata; Diggelen, Rudy Van; Grootjans, Ab P.; Kotowski, Wiktor

    2010-01-01

    The majority of fens in Europe have been transformed for agricultural purposes and have disappeared or become degraded. Fen meadows that developed under low-intensity management of fens also have become degraded. In this paper, we consider the available restoration methods, biotic constraints for

  11. 76 FR 40322 - Mt. Hood Meadows Ski Resort Parking Improvements

    Science.gov (United States)

    2011-07-08

    ... fleet. Also, the location of the current maintenance shop impedes traffic flow and removes potential... new Sunrise Vehicle Maintenance Shop on the north side of the Sunrise parking lot. DATES: Comments... increasing parking capacity and improving traffic flow in at Mt. Hood Meadows Ski Resort. Parking capacity...

  12. Riparian Meadow Response to Modern Conservation Grazing Management

    Science.gov (United States)

    Oles, Kristin M.; Weixelman, Dave A.; Lile, David F.; Tate, Kenneth W.; Snell, Laura K.; Roche, Leslie M.

    2017-09-01

    Riparian meadows occupy a small proportion of the public lands in the western United States but they provide numerous ecosystem services, including the production of high-quality forage for livestock grazing. Modern conservation management strategies (e.g., reductions in livestock stocking rates and adoption of new riparian grazing standards) have been implemented to better balance riparian conservation and livestock production objectives on publicly managed lands. We examined potential relationships between long-term changes in plant community, livestock grazing pressure and environmental conditions at two spatial scales in meadows grazed under conservation management strategies. Changes in plant community were not associated with either livestock stocking rate or precipitation at the grazing allotment (i.e., administrative) scale. Alternatively, both grazing pressure and precipitation had significant, albeit modest, associations with changes in plant community at the meadow (i.e., ecological site) scale. These results suggest that reductions in stocking rate have improved the balance between riparian conservation and livestock production goals. However, associations between elevation, site wetness, precipitation, and changes in plant community suggest that changing climate conditions (e.g., reduced snowpack and changes in timing of snowmelt) could trigger shifts in plant communities, potentially impacting both conservation and agricultural services (e.g., livestock and forage production). Therefore, adaptive, site-specific management strategies are required to meet grazing pressure limits and safeguard ecosystem services within individual meadows, especially under more variable climate conditions.

  13. Influence of high doses gamma radiation on group of meadow plants and water organisms

    International Nuclear Information System (INIS)

    Wlodek, St.; Wasilewski, A.; Indeka, L.; Kobuszewska, B.; Krzysztofik, B.; Ossowska-Cypryk, K.; Slomczynski, T.

    1979-01-01

    The plot of 100 square meters area has been irradiated for 526 days by gamma radiation which simulated the external radiation of the local fall-out. This field experiment has been performed in specially preserved conditions. The organisms of land and water complexes present in this area have received the total of 50 000 R in the center and 600 R on periphery. It has been shown that: changes in the quantitative and qualitative composition of bacteria and soil and water fungi were generally little: among the physiological groups the greatest disfunctions have been observed for the bacteria of the nitric cycle; Lemna minor appeared to be the most radiosensitive water plant which perished completely in the zone around the center of the plot what in turn resulted in secondary changes in the composition of water microflora and micro- and macrofauna; the growth of 14 species of meadow plants present around the center of the plot has been reduced about 25% of biomass in comparison with the control plots; on the other hand, the stimulation of growth of meadow plants, mostly weeds, has been observed on the periphery of the plot. (author)

  14. Influence of high doses gamma radiation on group of meadow plants and water organisms

    Energy Technology Data Exchange (ETDEWEB)

    Wlodek, St; Wasilewski, A; Indeka, L; Kobuszewska, B; Krzysztofik, B; Ossowska-Cypryk, K; Slomczynski, T

    1979-01-01

    The plot of 100 square meters area has been irradiated for 526 days by gamma radiation which simulated the external radiation of the local fall-out. This field experiment has been performed in specially preserved conditions. The organisms of land and water complexes present in this area have received the total of 50 000 R in the center and 600 R on periphery. It has been shown that: changes in the quantitative and qualitative composition of bacteria and soil and water fungi were generally little: among the physiological groups the greatest disfunctions have been observed for the bacteria of the nitric cycle; Lemna minor appeared to be the most radiosensitive water plant which perished completely in the zone around the center of the plot what in turn resulted in secondary changes in the composition of water microflora and micro- and macrofauna; the growth of 14 species of meadow plants present around the center of the plot has been reduced about 25% of biomass in comparison with the control plots; on the other hand, the stimulation of growth of meadow plants, mostly weeds, has been observed on the periphery of the plot.

  15. Quantifying and modelling the carbon sequestration capacity of seagrass meadows--a critical assessment.

    Science.gov (United States)

    Macreadie, P I; Baird, M E; Trevathan-Tackett, S M; Larkum, A W D; Ralph, P J

    2014-06-30

    Seagrasses are among the planet's most effective natural ecosystems for sequestering (capturing and storing) carbon (C); but if degraded, they could leak stored C into the atmosphere and accelerate global warming. Quantifying and modelling the C sequestration capacity is therefore critical for successfully managing seagrass ecosystems to maintain their substantial abatement potential. At present, there is no mechanism to support carbon financing linked to seagrass. For seagrasses to be recognised by the IPCC and the voluntary C market, standard stock assessment methodologies and inventories of seagrass C stocks are required. Developing accurate C budgets for seagrass meadows is indeed complex; we discuss these complexities, and, in addition, we review techniques and methodologies that will aid development of C budgets. We also consider a simple process-based data assimilation model for predicting how seagrasses will respond to future change, accompanied by a practical list of research priorities. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Structure and floristic similarities of upper montane forests in Serra Fina mountain range, southeastern Brazil

    Directory of Open Access Journals (Sweden)

    Leonardo Dias Meireles

    2015-03-01

    Full Text Available The upper montane forests in the southern and southeastern regions of Brazil have an unusual and discontinuous geographic distribution at the top of the Atlantic coastal mountain ranges. To describe the floristic composition and structure of the Atlantic Forest near its upper altitudinal limit in southeastern Brazil, 30 plots with 10 × 10 m were installed in three forest sites between 2,200 and 2,300 m.a.s.l. at Serra Fina. The floristic composition and phytosociological structure of this forest were compared with other montane and upper montane forests. In total, 704 individuals were included, belonging to 24 species, 15 families, and 19 genera. Myrsinaceae, Myrtaceae, Symplocaceae, and Cunoniaceae were the most important families, and Myrsine gardneriana, Myrceugenia alpigena, Weinmannia humilis, and Symplocos corymboclados were the most important species. The three forest sites revealed differences in the abundance of species, density, canopy height, and number of stems per individual. The upper montane forests showed structural similarities, such as lower richness, diversity, and effective number of species, and they tended to have higher total densities and total dominance per hectare to montane forests. The most important species in these upper montane forests belong to Austral-Antartic genera or neotropical and pantropical genera that are typical of montane areas. The high number of species shared by these forests suggests past connections between the vegetation in southern Brazilian high-altitude areas.

  17. Unveiling the Hidden Bat Diversity of a Neotropical Montane Forest.

    Directory of Open Access Journals (Sweden)

    Gloriana Chaverri

    Full Text Available Mountain environments, characterized by high levels of endemism, are at risk of experiencing significant biodiversity loss due to current trends in global warming. While many acknowledge their importance and vulnerability, these ecosystems still remain poorly studied, particularly for taxa that are difficult to sample such as bats. Aiming to estimate the amount of cryptic diversity among bats of a Neotropical montane cloud forest in Talamanca Range-south-east Central America-, we performed a 15-night sampling campaign, which resulted in 90 captured bats belonging to 8 species. We sequenced their mitochondrial cytochrome c oxidase subunit I (COI and screened their inter- and intraspecific genetic variation. Phylogenetic relations with conspecifics and closely related species from other geographic regions were established using Maximum Likelihood and Bayesian inference methods, as well as median-joining haplotype networks. Mitochondrial lineages highly divergent from hitherto characterized populations (> 9% COI dissimilarity were found in Myotis oxyotus and Hylonycteris underwoodi. Sturnira burtonlimi and M. keaysi also showed distinct mitochondrial structure with sibling species and/or populations. These results suggest that mountains in the region hold a high degree of endemicity potential that has previously been ignored in bats. They also warn of the high extinction risk montane bats may be facing due to climatic change, particularly in isolated mountain systems like Talamanca Range.

  18. [Relationships between horqin meadow NDVI and meteorological factors].

    Science.gov (United States)

    Qu, Cui-ping; Guan, De-xin; Wang, An-zhi; Jin, Chang-jie; Wu, Jia-bing; Wang, Ji-jun; Ni, Pan; Yuan, Feng-hui

    2009-01-01

    Based on the 2000-2006 MODIS 8-day composite NDVI and day-by-day meteorological data, the seasonal and inter-annual variations of Horqin meadow NDVI as well as the relationships between the NDVI and relevant meteorological factors were studied. The results showed that as for the seasonal variation, Horqin meadow NDVI was more related to water vapor pressure than to precipitation. Cumulated temperature and cumulated precipitation together affected the inter-annual turning-green period significantly, and the precipitation in growth season (June and July), compared with that in whole year, had more obvious effects on the annual maximal NDVI. The analysis of time lag effect indicated that water vapor pressure had a persistent (about 12 days) prominent effect on the NDVI. The time lag effect of mean air temperature was 11-15 days, and the cumulated dual effect of the temperature and precipitation was 36-52 days.

  19. Effects of disturbance regime on carbohydrate reserves in meadow plants

    Czech Academy of Sciences Publication Activity Database

    Janeček, Štěpán; Bartušková, Alena; Bartoš, Michael; Altman, Jan; de Bello, Francesco; Doležal, Jiří; Latzel, Vít; Lanta, V.; Lepš, J.; Klimešová, Jitka

    2015-01-01

    Roč. 7, plv123 (2015), s. 1-16 ISSN 2041-2851 R&D Projects: GA ČR GA526/09/0963; GA ČR GAP505/12/1296; GA ČR GB14-36079G Institutional support: RVO:67985939 Keywords : Carbohydrates * management * meadow Subject RIV: EH - Ecology, Behaviour Impact factor: 2.079, year: 2015

  20. Impacts of urban wastewater discharge on seagrass meadows ( Zostera noltii)

    Science.gov (United States)

    Cabaço, Susana; Machás, Raquel; Vieira, Vasco; Santos, Rui

    2008-06-01

    The abiotic disturbance of urban wastewater discharge and its effects in the population structure, plant morphology, leaf nutrient content, epiphyte load and macroalgae abundance of Zostera noltii meadows were investigated in Ria Formosa coastal lagoon, southern Portugal using both univariate and multivariate analysis. Four sites were assessed, on a seasonal basis, along a gradient from a major Waste Water Treatment Works (WWTW) discharge to a main navigation channel. The wastewater discharge caused an evident environmental disturbance through the nutrient enrichment of the water and sediment, particularly of ammonium. Zostera noltii of the sites closest to the nutrient source showed higher leaf N content, clearly reflecting the nitrogen load. The anthropogenic nutrient enrichment resulted in higher biomass, and higher leaf and internode length, except for the meadow closest to the wastewater discharge (270 m). The high ammonium concentration (158-663 μM) in the water at this site resulted in the decrease of biomass, and both the leaf and internode length, suggesting a toxic effect on Z. noltii. The higher abundance of macroalgae and epiphytes found in the meadow closest to the nutrient source may also affect the species negatively. Shoot density was higher at the nutrient-undisturbed site. Two of the three abiotic processes revealed by Principal Component Analysis were clearly related to the WWTW discharge, a contrast between water column salinity and nutrient concentration and a sediment contrast between both porewater nutrients and temperature and redox potential. A multiple regression analysis showed that these abiotic processes had a significant effect on the biomass-density dynamics of meadows and on the overall size of Z. noltii plants, respectively. Results show that the wastewater discharge is an important source of environmental disturbance and nutrients availability in Ria Formosa lagoon affecting the population structure, morphology and N content of Z

  1. Predation risk of artificial ground nests in managed floodplain meadows

    Science.gov (United States)

    Arbeiter, Susanne; Franke, Elisabeth

    2018-01-01

    Nest predation highly determines the reproductive success in birds. In agricultural grasslands, vegetation characteristics and management practices influences the predation risk of ground breeders. Little is known so far on the predation pressure on non-passerine nests in tall swards. Investigations on the interaction of land use with nesting site conditions and the habitat selection of nest predators are crucial to develop effective conservation measures for grassland birds. In this study, we used artificial nests baited with quail and plasticine eggs to identify potential predators of ground nests in floodplain meadows and related predation risk to vegetation structure and grassland management. Mean daily predation rate was 0.01 (±0.012) after an exposure duration of 21 days. 70% of all observed nest predations were caused by mammals (Red Fox and mustelids) and 17.5% by avian predators (corvids). Nest sites close to the meadow edge and those providing low forb cover were faced with a higher daily predation risk. Predation risk also increased later in the season. Land use in the preceding year had a significant effect on predation risk, showing higher predation rates on unmanaged sites than on mown sites. Unused meadows probably attract mammalian predators, because they provide a high abundance of small rodents and a more favourable vegetation structure for foraging, increasing also the risk of incidental nest predations. Although mowing operation is a major threat to ground-nesting birds, our results suggest that an annual removal of vegetation may reduce predation risk in the subsequent year.

  2. Mapping mountain meadow with high resolution and polarimetric SAR data

    International Nuclear Information System (INIS)

    Tian, Bangsen; Li, Zhen; Xu, Juan; Fu, Sitao; Liu, Jiuli

    2014-01-01

    This paper presents a method to map the large grassland in the eastern margin of the Tibetan Plateau with the high resolution polarimetric SAR (PolSAR) imagery. When PolSAR imagery is used for land cover classification, the brightness of a SAR image is affected by topography due to varying projection between ground and image coordinates. The objective of this paper is twofold: (1) we first extend the theory of SAR terrain correction to the polarimetric case, to utilize the entire available polarimetric signature, where correction is performed explicitly based on a matrix format like covariance matrix. (2) Next, the orthoectified PolSAR is applied to classify mountain meadow and investigate the potential of PolSAR in mapping grassland. In this paper, the gamma naught radiometric correction estimates the local illuminated area at each grid point in the radar geometry. Then, each element of the coherency matrix is divided by the local area to produce a polarimetric product. Secondly, the impact of radiometric correction upon classification accuracy is investigated. A supervised classification is performed on the orthorectified Radarsat-2 PolSAR to map the spatial distribution of meadow and evaluate monitoring capabilities of mountain meadow

  3. Seascape ecology in Posidonia oceanica seagrass meadows: Linking structure and ecological processes for management

    OpenAIRE

    Abadie, Arnaud; Pace, Matthew; Gobert, Sylvie; Borg, Joseph

    2018-01-01

    Seagrass meadows constitute marine habitats in shallow water temperate and tropical coastal areas worldwide that have a high ecological and economic importance. Amongst the 60 or so seagrass species, the endemic Mediterranean species Posidonia oceanica forms meadows that are arguably the most important shallow water coastal habitat in the region but which are subjected to high anthropogenic pressures. Because of the relatively large size of the plant, the meadows formed by this seagrass have ...

  4. Seagrass meadows as a globally significant carbonate reservoir

    KAUST Repository

    Mazarrasa, I.; Marbà , N.; Lovelock, C. E.; Serrano, O.; Lavery, P. S.; Fourqurean, J. W.; Kennedy, H.; Mateo, M. A.; Krause-Jensen, D.; Steven, A. D. L.; Duarte, Carlos M.

    2015-01-01

    There has been growing interest in quantifying the capacity of seagrass ecosystems to act as carbon sinks as a natural way of offsetting anthropogenic carbon emissions to the atmosphere. However, most of the efforts have focused on the particulate organic carbon (POC) stocks and accumulation rates and ignored the particulate inorganic carbon (PIC) fraction, despite important carbonate pools associated with calcifying organisms inhabiting the meadows, such as epiphytes and benthic invertebrates, and despite the relevance that carbonate precipitation and dissolution processes have in the global carbon cycle. This study offers the first assessment of the global PIC stocks in seagrass sediments using a synthesis of published and unpublished data on sediment carbonate concentration from 403 vegetated and 34 adjacent un-vegetated sites. PIC stocks in the top 1 m of sediment ranged between 3 and 1660 Mg PIC ha−1, with an average of 654 ± 24 Mg PIC ha−1, exceeding those of POC reported in previous studies by about a factor of 5. Sedimentary carbonate stocks varied across seagrass communities, with meadows dominated by Halodule, Thalassia or Cymodocea supporting the highest PIC stocks, and tended to decrease polewards at a rate of −8 ± 2 Mg PIC ha−1 per degree of latitude (general linear model, GLM; p < 0.0003). Using PIC concentrations and estimates of sediment accretion in seagrass meadows, the mean PIC accumulation rate in seagrass sediments is found to be 126.3 ± 31.05 g PIC m−2 yr−1. Based on the global extent of seagrass meadows (177 000 to 600 000 km2), these ecosystems globally store between 11 and 39 Pg of PIC in the top metre of sediment and accumulate between 22 and 75 Tg PIC yr−1, representing a significant contribution to the carbonate dynamics of coastal areas. Despite the fact that these high rates of carbonate accumulation imply CO2

  5. Seagrass meadows as a globally significant carbonate reservoir

    KAUST Repository

    Mazarrasa, I.

    2015-08-24

    There has been growing interest in quantifying the capacity of seagrass ecosystems to act as carbon sinks as a natural way of offsetting anthropogenic carbon emissions to the atmosphere. However, most of the efforts have focused on the particulate organic carbon (POC) stocks and accumulation rates and ignored the particulate inorganic carbon (PIC) fraction, despite important carbonate pools associated with calcifying organisms inhabiting the meadows, such as epiphytes and benthic invertebrates, and despite the relevance that carbonate precipitation and dissolution processes have in the global carbon cycle. This study offers the first assessment of the global PIC stocks in seagrass sediments using a synthesis of published and unpublished data on sediment carbonate concentration from 403 vegetated and 34 adjacent un-vegetated sites. PIC stocks in the top 1 m of sediment ranged between 3 and 1660 Mg PIC ha−1, with an average of 654 ± 24 Mg PIC ha−1, exceeding those of POC reported in previous studies by about a factor of 5. Sedimentary carbonate stocks varied across seagrass communities, with meadows dominated by Halodule, Thalassia or Cymodocea supporting the highest PIC stocks, and tended to decrease polewards at a rate of −8 ± 2 Mg PIC ha−1 per degree of latitude (general linear model, GLM; p < 0.0003). Using PIC concentrations and estimates of sediment accretion in seagrass meadows, the mean PIC accumulation rate in seagrass sediments is found to be 126.3 ± 31.05 g PIC m−2 yr−1. Based on the global extent of seagrass meadows (177 000 to 600 000 km2), these ecosystems globally store between 11 and 39 Pg of PIC in the top metre of sediment and accumulate between 22 and 75 Tg PIC yr−1, representing a significant contribution to the carbonate dynamics of coastal areas. Despite the fact that these high rates of carbonate accumulation imply CO2

  6. The microbially mediated soil organic carbon loss under degenerative succession in an alpine meadow.

    Science.gov (United States)

    Zhang, Yuguang; Liu, Xiao; Cong, Jing; Lu, Hui; Sheng, Yuyu; Wang, Xiulei; Li, Diqiang; Liu, Xueduan; Yin, Huaqun; Zhou, Jizhong; Deng, Ye

    2017-07-01

    Land-cover change has long been recognized as having marked effect on the amount of soil organic carbon (SOC). However, the microbially mediated processes and mechanisms on SOC are still unclear. In this study, the soil samples in a degenerative succession from alpine meadow to alpine steppe meadow in the Qinghai-Tibetan Plateau were analysed using high-throughput technologies, including Illumina sequencing and geochip functional gene arrays. The soil microbial community structure and diversity were significantly (p carbon degradation genes (e.g., pectin and hemicellulose) was significantly higher in alpine steppe meadow than in alpine meadow, but the relative abundance of soil recalcitrant carbon degradation genes (e.g., chitin and lignin) showed the opposite tendency. The Biolog Ecoplate experiment showed that microbially mediated soil carbon utilization was more active in alpine steppe meadow than in alpine meadow. Consequently, more soil labile carbon might be decomposed in alpine steppe meadow than in alpine meadow. Therefore, the degenerative succession of alpine meadow because of climate change or anthropogenic activities would most likely decrease SOC and nutrients medicated by changing soil microbial community structure and their functional potentials for carbon decomposition. © 2017 John Wiley & Sons Ltd.

  7. Climate change and Mediterranean seagrass meadows: a synopsis for environmental managers

    Directory of Open Access Journals (Sweden)

    G. PERGENT

    2014-02-01

    Full Text Available This synopsis focuses on the effects of climate change on Mediterranean seagrasses, and associated communities, and on the contribution of the main species, Posidonia oceanica, to the mitigation of climate change effects through its role of sequestering carbon dioxide. Whilst the regression of seagrass meadows is well documented, generally linked to anthropogenic pressures, global warming could be a cause of new significant regressions, notably linked to the introduction of exotic species, the rise of Sea-Surface Temperature (SST, and relative sea level. Seagrass communities could also be affected by climate change through the replacement of seagrass species having high structural complexity by species of lower complexity and even by opportunistic introduced species. Although it is currently very difficult to predict the consequences of these alterations and their cascade effects, two main conflicting trends in the functioning of seagrass ecosystems that could occur are acceleration of the herbivore pathway or of the detritivore pathway. The mean net primary production of the dominant species, Posidonia oceanica, is relatively high and can be estimated to range between 92.5 to 144.7 g C m-2 a-1. Around 27% of the total carbon fixed by this species enters the sedimentary pathway leading to formation, over millennia, of highly organic deposits rich in refractory carbon. At the Mediterranean scale, the sequestration rate might reach 1.09 Tg C a-1. The amount of this stored carbon is estimated to range from 71 to 273 kg C m-2, which when considered at the Mediterranean scale would represent 11 to 42% of the CO2 emissions produced by Mediterranean countries since the beginning of the Industrial Revolution. The greatest value of the P. oceanica ecosystem, in the context of mitigation of global climate change, is linked to this vast long-term carbon stock accumulated over the millennia, and therefore, efforts should be focused on preserving the

  8. Effects of tropical montane forest disturbance on epiphytic macrolichens

    Energy Technology Data Exchange (ETDEWEB)

    Benitez, Angel [Instituto de Ecologia, Herbario HUTPL, Universidad Tecnica Particular de Loja, San Cayetano s/n, Loja (Ecuador); Prieto, Maria, E-mail: maria.prieto@urjc.es [Area de Biodiversidad y Conservacion, ESCET, Universidad Rey Juan Carlos, Mostoles, E-28933, Madrid (Spain); Gonzalez, Yadira [Instituto de Ecologia, Herbario HUTPL, Universidad Tecnica Particular de Loja, San Cayetano s/n, Loja (Ecuador); Aragon, Gregorio [Area de Biodiversidad y Conservacion, ESCET, Universidad Rey Juan Carlos, Mostoles, E-28933, Madrid (Spain)

    2012-12-15

    The high diversity of epiphytes typical of undisturbed montane tropical forests has been negatively affected by continuous deforestation and forest conversion to secondary vegetation. Macrolichens are an important component of these epiphytes. Because their physiology is strongly coupled to humidity and solar radiation, we hypothesized that microclimatic changes derived from forest clearing and logging can affect the diversity of these poikilohydric organisms. In southern Ecuador, we examined three types of forests according to a disturbance gradient (primary forests, secondary forests, and monospecific forests of Alnus acuminata) for the presence/absence and coverage of epiphytic macrolichens that we identified on 240 trees. We found that total richness tended to decrease when the range of the disturbance increased. The impoverishment was particularly drastic for 'shade-adapted lichens', while the richness of 'heliophytic lichens' increased in the drier conditions of secondary growth. Epiphytic composition also differed significantly among the three types of forests, and the similarity decreased when the range of the disturbance was greater. We concluded that a span of 40 years of recovery by secondary vegetation was not enough to regenerate the diversity of epiphytic macrolichens that was lost due to forest disturbances. -- Highlights: Black-Right-Pointing-Pointer Tropical montane forest disturbance drastically reduced macrolichen diversity. Black-Right-Pointing-Pointer Species loss was most severe for the 'shade-adapted lichens' because high radiation is harmful to them. Black-Right-Pointing-Pointer In secondary forests lichen diversity of native forests was not regenerated. Black-Right-Pointing-Pointer The protection of remnants of primary tropical forest might help to preserve a diverse community of epiphytic macrolichens.

  9. Effects of tropical montane forest disturbance on epiphytic macrolichens

    International Nuclear Information System (INIS)

    Benítez, Ángel; Prieto, María; González, Yadira; Aragón, Gregorio

    2012-01-01

    The high diversity of epiphytes typical of undisturbed montane tropical forests has been negatively affected by continuous deforestation and forest conversion to secondary vegetation. Macrolichens are an important component of these epiphytes. Because their physiology is strongly coupled to humidity and solar radiation, we hypothesized that microclimatic changes derived from forest clearing and logging can affect the diversity of these poikilohydric organisms. In southern Ecuador, we examined three types of forests according to a disturbance gradient (primary forests, secondary forests, and monospecific forests of Alnus acuminata) for the presence/absence and coverage of epiphytic macrolichens that we identified on 240 trees. We found that total richness tended to decrease when the range of the disturbance increased. The impoverishment was particularly drastic for “shade-adapted lichens”, while the richness of “heliophytic lichens” increased in the drier conditions of secondary growth. Epiphytic composition also differed significantly among the three types of forests, and the similarity decreased when the range of the disturbance was greater. We concluded that a span of 40 years of recovery by secondary vegetation was not enough to regenerate the diversity of epiphytic macrolichens that was lost due to forest disturbances. -- Highlights: ► Tropical montane forest disturbance drastically reduced macrolichen diversity. ► Species loss was most severe for the “shade-adapted lichens” because high radiation is harmful to them. ► In secondary forests lichen diversity of native forests was not regenerated. ► The protection of remnants of primary tropical forest might help to preserve a diverse community of epiphytic macrolichens.

  10. Influence of Beaver-Induced Complexity on Storage of Organic Carbon and Sediment in Colorado Mountain Streams

    Science.gov (United States)

    Laurel, D.; Wohl, E.

    2016-12-01

    Beaver meadows (complexes of multiple different aged beaver dams and ponds) influence the storage of water, sediment, and nutrients. Although beaver meadows compose only a small fraction of catchment area, they provide a potentially large role in retaining these fluxes in mountain watersheds. Multiple dams and ponds in beaver meadows increase overbank flows leading to an anastomosing stream channel planform, and deposition of fine sediment along with particulate organic carbon. An earlier study estimated a range of cumulative carbon stored in 27 beaver meadows east of the continental divide in Rocky Mountain National Park. Storage ranged from 735,800 to 2.8 x 106 Mg carbon, with the high value estimating storage if all the meadows had active beaver (historic conditions pre-European settlement) and the lower value estimating current conditions where many of the meadows are abandoned. We combined geomorphic surveys, soil depth probing by rebar, and soil cores analyzed for carbon content to investigate the influence of beaver activity, meadow size, and meadow placement within the drainage on catchment-scale fluxes of fine sediment and organic carbon. We found carbon storage in floodplain soils to be highly variable across both active and abandoned meadows; however, active beaver meadows store more carbon on average than abandoned meadows. In addition, active meadows with high levels of beaver activity (multiple colonies) stored greater volumes of fine sediment behind dams and in ponds. These results have implications for the restoration potential of abandoned beaver meadows in mountain environments to store greater volumes of sediment and more organic carbon if beaver are successfully reintroduced.

  11. Turbulent mixing and fluid transport within Florida Bay seagrass meadows

    Science.gov (United States)

    Hansen, Jennifer C. R.; Reidenbach, Matthew A.

    2017-10-01

    Seagrasses serve an important function in the ecology of Florida Bay, providing critical nursery habitat and a food source for a variety of organisms. They also create significant benthic structure that induces drag, altering local hydrodynamics that can influence mixing and nutrient dynamics. Thalassia testudinum seagrass meadows were investigated to determine how shoot density and morphometrics alter local wave conditions, the generation of turbulence, and fluid exchange above and within the canopy. Sparsely vegetated and densely vegetated meadows were monitored, with shoot densities of 259 ± 26 and 484 ± 78 shoots m-2, respectively. The temporal and spatial structure of velocity and turbulence were measured using acoustic Doppler velocimeters and an in situ particle image velocimetry (PIV) system positioned both above and within the seagrass canopy. The retention of fluid within the canopy was determined by examining e-folding times calculated from the concentration curves of dye plumes released within the seagrass canopy. Results show that a shear layer with an inflection point develops at the top of the seagrass canopy, which generates instabilities that impart turbulence into the seagrass meadow. Compared to the overlying water column, turbulence was enhanced within the sparse canopy due to flow interaction with the seagrass blades, but reduced within the dense canopy. Wave generated oscillatory motion penetrated deeper into the canopy than unidirectional currents, enhancing fluid exchange. Both shoot density and the relative magnitude of wave- versus current-driven flow conditions were found to be important controls on turbulent exchange of water masses across the canopy-water interface.

  12. Interoperability challenges for the Sustainable Management of seagrass meadows (Invited)

    Science.gov (United States)

    Nativi, S.; Pastres, R.; Bigagli, L.; Venier, C.; Zucchetta, M.; Santoro, M.

    2013-12-01

    Seagrass meadows (marine angiosperm plants) occupy less than 0.2% of the global ocean surface, annually store about 10-18% of the so-called 'Blue Carbon', i.e. the Carbon stored in coastal vegetated areas. Recent literature estimates that the flux to the long-term carbon sink in seagrasses represents 10-20% of seagrasses global average production. Such figures can be translated into economic benefits, taking into account that a ton of carbon dioxide in Europe is paid at around 15 € in the carbon market. This means that the organic carbon retained in seagrass sediments in the Mediterranean is worth 138 - 1128 billion €, which represents 6-23 € per square meter. This is 9-35 times more than one square meter of tropical forest soil (0.66 € per square meter), or 5-17 times when considering both the above and the belowground compartments in tropical forests. According the most conservative estimations, about 10% of the Mediterranean meadows have been lost during the last century. In the framework of the GEOSS (Global Earth Observation System of Systems) initiative, the MEDINA project (funded by the European Commission and coordinated by the University of Ca'Foscari in Venice) prepared a showcase as part of the GEOSS Architecture Interoperability Pilot -phase 6 (AIP-6). This showcase aims at providing a tool for the sustainable management of seagrass meadows along the Mediterranean coastline. The application is based on an interoperability framework providing a set of brokerage services to easily ingest and run a Habitat Suitability model (a model predicting the probability a given site to provide a suitable habitat for the development of seagrass meadow and the average coverage expected). The presentation discusses such a framework explaining how the input data is discovered, accessed and processed to ingest the model (developed in the MEDINA project). Furthermore, the brokerage framework provides the necessary services to run the model and visualize results

  13. A constructed wet meadow model for forested lands in the Southwest

    Science.gov (United States)

    Dave Pawelek; Roy Jemison; Daniel Neary

    1999-01-01

    Improving primary roads in the Zuni Mountains of New Mexico must take into consideration the wet meadows and upland areas. This study looks at spring flow rates, erosion, channels and changes in plant cover and composition. The goal is to help planners design environmentally sensitive roadways for wet meadow areas.

  14. SYNSYSTEMATIQUE DES PRAIRIES DE FRANCE (SYNSYSTEMATIC OF THE MEADOWS OF FRANCE

    Directory of Open Access Journals (Sweden)

    J.M. GEHU

    1999-01-01

    Full Text Available The synsystematic diagram of the meadows of France proposed in this work enumerates the main associations and the prairial superior unities of France giving them their great synecological features. The majority of these communities of meadows are usable in cutting or in pasture. They are grouped in the three following classes: Arrhenatheretea elatioris, Molinio-Juncetea and Agrostietea stoloniferae.

  15. Foraging site choice and diet selection of Meadow Pipits Anthus pratensis breeding on grazed salt marshes

    NARCIS (Netherlands)

    van Klink, Roel; Mandema, Freek S.; Bakker, Jan P.; Tinbergen, Joost M.

    2014-01-01

    Capsule Breeding Meadow Pipits foraged for caterpillars and large spiders in vegetation that was less heterogeneous than vegetation at random locations.Aims To gain a better understanding of the foraging ecology of breeding Meadow Pipits on grazed coastal salt marshes, we tested three hypotheses:

  16. Hydrological landscape settings of base-rich fen mires and fen meadows : an overview

    NARCIS (Netherlands)

    Grootjans, A.P.; Adema, E.B.; Bleuten, W.; Joosten, H.; Madaras, M.; Janáková, M.; Middleton, B.

    2006-01-01

    Question: Why do similar fen meadow communities occur in different landscapes? How does the hydrological system sustain base-rich fen mires and fen meadows? Location: Interdunal wetlands and heathland pools in The Netherlands, percolation mires in Germany, Poland, and Siberia, and calcareous spring

  17. Divergent Impacts of Two Cattle Types on Vegetation in Coastal Meadows: Implications for Management

    Science.gov (United States)

    Laurila, Marika; Huuskonen, Arto; Pesonen, Maiju; Kaseva, Janne; Joki-Tokola, Erkki; Hyvärinen, Marko

    2015-11-01

    The proportion of beef cattle in relation to the total number of cattle has increased in Europe, which has led to a higher contribution of beef cattle in the management of semi-natural grasslands. Changes in vegetation caused by this change in grazers are virtually unexplored so far. In the present study, the impacts of beef and dairy cattle on vegetation structure and composition were compared on Bothnian Bay coastal meadows. Vegetation parameters were measured in seven beef cattle, six dairy heifer pastures, and in six unmanaged meadows. Compared to unmanaged meadows, vegetation in grazed meadows was significantly lower in height and more frequently colonized by low-growth species. As expected, vegetation grazed by beef cattle was more open than that on dairy heifer pastures where litter cover and proportion of bare ground were in the same level as in the unmanaged meadows. However, the observed differences may have in part arisen from the higher cattle densities in coastal meadows grazed by beef cattle than by dairy heifers. The frequencies of different species groups and the species richness values of vegetation did not differ between the coastal meadows grazed by the two cattle types. One reason for this may be the relatively short management history of the studied pastures. The potential differences in grazing impacts of the two cattle types on vegetation structure can be utilized in the management of coastal meadows for species with divergent habitat requirements.

  18. Seed germination ecology of meadow knapweed (Centaurea x moncktonii) populations in New York State

    Science.gov (United States)

    The introduced meadow knapweed (Centaurea x moncktonii), a hybrid of black (C. nigra) and brown (C. jacea) knapweeds, appears to be common and expanding in New York agricultural lands, including pastures, meadows and waste areas. The biology and ecology of the hybrid is mostly unstudied, such as its...

  19. Net primary productivity of subalpine meadows in Yosemite National Park in relation to climate variability

    Science.gov (United States)

    Peggy E. Moore; Jan W. van Wagtendonk; Julie L. Yee; Mitchel P. McClaran; David N. Cole; Neil K. McDougald; Matthew L. Brooks

    2013-01-01

    Subalpine meadows are some of the most ecologically important components of mountain landscapes, and primary productivity is important to the maintenance of meadow functions. Understanding how changes in primary productivity are associated with variability in moisture and temperature will become increasingly important with current and anticipated changes in climate....

  20. Artificial Warming of Arctic Meadow under Pollution Stress: Experimental design

    Science.gov (United States)

    Moni, Christophe; Silvennoinen, Hanna; Fjelldal, Erling; Brenden, Marius; Kimball, Bruce; Rasse, Daniel

    2014-05-01

    Boreal and arctic terrestrial ecosystems are central to the climate change debate, notably because future warming is expected to be disproportionate as compared to world averages. Likewise, greenhouse gas (GHG) release from terrestrial ecosystems exposed to climate warming is expected to be the largest in the arctic. Artic agriculture, in the form of cultivated grasslands, is a unique and economically relevant feature of Northern Norway (e.g. Finnmark Province). In Eastern Finnmark, these agro-ecosystems are under the additional stressor of heavy metal and sulfur pollution generated by metal smelters of NW Russia. Warming and its interaction with heavy metal dynamics will influence meadow productivity, species composition and GHG emissions, as mediated by responses of soil microbial communities. Adaptation and mitigation measurements will be needed. Biochar application, which immobilizes heavy metal, is a promising adaptation method to promote positive growth response in arctic meadows exposed to a warming climate. In the MeadoWarm project we conduct an ecosystem warming experiment combined to biochar adaptation treatments in the heavy-metal polluted meadows of Eastern Finnmark. In summary, the general objective of this study is twofold: 1) to determine the response of arctic agricultural ecosystems under environmental stress to increased temperatures, both in terms of plant growth, soil organisms and GHG emissions, and 2) to determine if biochar application can serve as a positive adaptation (plant growth) and mitigation (GHG emission) strategy for these ecosystems under warming conditions. Here, we present the experimental site and the designed open-field warming facility. The selected site is an arctic meadow located at the Svanhovd Research station less than 10km west from the Russian mining city of Nikel. A splitplot design with 5 replicates for each treatment is used to test the effect of biochar amendment and a 3oC warming on the Arctic meadow. Ten circular

  1. Photo series for quantifying forest fuels in Mexico: montane subtropical forests of the Sierra Madre del Sur and temperate forests and montane shrubland of the northern Sierra Madre Oriental

    Science.gov (United States)

    Jorge E. Morfin-Rios; Ernesto Alvarado-Celestino; Enrique J. Jardel-Pelaez; Robert E. Vihnanek; David K. Wright; Jose M. Michel-Fuentes; Clinton S. Wright; Roger D. Ottmar; David V. Sandberg; Andres Najera-Diaz

    2008-01-01

    Single wide-angle and stereo photographs display a range of forest ecosystems conditions and fuel loadings in montane subtropical forests of the Sierra Madre del Sur and temperate forests and montane shrubland of the northern Sierra Madre Oriental of Mexico. Each group of photographs includes inventory information summarizing overstory vegetation composition and...

  2. Integrating hydrogeophysics and hydrological tracers to characterise the spatial structure of groundwater storage in the critical zone of montane environments

    Science.gov (United States)

    Dick, J.; Tetzlaff, D.; Bradford, J.; Soulsby, C.

    2015-12-01

    It is increasingly recognised that groundwater (GW) in montane watersheds has a major influence on the distribution of vegetation communities and ecosystem function, as well as sustaining downstream river flows. In glaciated landscapes, complex and heterogenous drift deposits can have a dominant influence on GW stores and fluxes, and form a poorly understood component of the critical zone. Given the logistical problems and limitations of drilling observation wells in such terrain, hydrogeophysics has outstanding potential to help characterise aquifer structure and understand shallow GW in the critical zone of montane environments. We present the results of electrical resistivity tomography (ERT) surveys in an intensively monitored 3.2km2 watershed in the Scottish Highlands with a strong glacial past. We sought to characterise the structure and spatial organisation of GW stores in diverse quaternary drift deposits. This utilized distributed ERT transects that provided a basis for spatial interpolation using geostatistical methods and high resolution LiDAR surveys. Some transects coincided with shallow observation wells that were used to "ground-truth" the inversion of resistivity data. The surveys showed that the drifts covered around 70% of the catchment and varied from 5m deep on the hillslopes to 40m in the valleys. The water table was within 0.2m of the soil surface in the valley bottom areas and about 1.5m deep on steeper hillslopes. The water content of drifts inferred by the ERT surveys and characterisation of the aquifer properties showed highest water content in the peat (~80%) and basal till (20-30%), and low storage in moraine deposits (10%). Upscaling these estimates of inferred storage to the catchment scale indicated around ~2-3 m of GW storage, equivalent to around 4-6 years of effective precipitation. This generally compared well with independent storage estimates inferred from long-term stable isotope time series collected from the aquifers

  3. Landscape-scale drivers of glacial ecosystem change in the montane forests of the eastern Andean flank, Ecuador

    NARCIS (Netherlands)

    Loughlin, N.J.D.; Gosling, W.D.; Coe, A.L.; Gulliver, P.; Mothes, P.; Montoya, E.

    2018-01-01

    Understanding the impact of landscape-scale disturbance events during the last glacial period is vital in accurately reconstructing the ecosystem dynamics of montane environments. Here, a sedimentary succession from the tropical montane cloud forest of the eastern Andean flank of Ecuador provides

  4. Temporal changes of meadow and peatbog vegetation in the landscape of a small-scale river valley in Central Roztocze

    Directory of Open Access Journals (Sweden)

    Bożenna Czarnecka

    2015-07-01

    Full Text Available The Szum is a right-side tributary of the Tanew River crossing the southern escarpment zone of the Central Roztocze region (SE Poland. Downstream of the strict river break in a section between the 10th and 12th km of the river course in the Szum valley, meadow and peatbog complexes have developed, associated with semi-hydrogenic and marshy soils. In an area of approx. 13 ha of the most valuable non-forest habitats, a variety of plant communities have been identified, including habitats of the Natura 2000 network and habitats that are protected under the Regulation of the Minister of the Environment (2001. These are, for instance, meadow associations Lysimachio vulgaris-Filipenduletum, Lythro-Filipenduletum, Filipendulo ulmariae-Menthetum longifoliae, Angelico-Cirsietum oleracei, and Cirsietum rivularis. The moss–sedge and sphagnum bog communities comprise noteworthy associations Caricetum limosae, Rhynchosporetum albae, Caricetum lasiocarpae, Caricetum paniceo-lepidocarpae, Caricetum davallianae, and Sphagnetum magellanici. These communities are composed of ca. 160 vascular plant species and 40 moss and liverwort species. In 1999–2014, the greatest changes occurred within macroforb meadows, i.e. small Angelico-Cirsietum oleracei and Cirsietum rivularis patches have been transformed into Lysimachio vulgaris-Filipenduletum, while some patches of the latter association have been transformed into a Caricetum acutiformis rush. Several patches of bog-spring associations Caricetum paniceo-lepidocarpae and Carici canescentis-Agrostietum caninae have been irretrievably destroyed. Sphagnetum magellanici appears to be the least stable community among the preserved peatbogs. The changes of meadow and peatbog vegetation observed for the last 15 years are a consequence of natural processes that take place in the river valley and to a large extent human activity connected with the so-called small-scale water retention as well as the presence of a beaver

  5. Assessing the links among environmental contaminants, endocrinology, and parasites to understand amphibian declines in montane regions of Costa Rica.

    Science.gov (United States)

    Leary, Christopher J; Ralicki, Hannah F; Laurencio, David; Crocker-Buta, Sarah; Malone, John H

    2018-01-01

    Amphibians inhabiting montane riparian zones in the Neotropics are particularly vulnerable to decline, but the reasons are poorly understood. Because environmental contaminants, endocrine disruption, and pathogens often figure prominently in amphibian declines it is imperative that we understand how these factors are potentially interrelated to affect montane populations. One possibility is that increased precipitation associated with global warming promotes the deposition of contaminants in montane regions. Increased exposure to contaminants, in turn, potentially elicits chronic elevations in circulating stress hormones that could contribute to montane population declines by compromising resistance to pathogens and/or production of sex steroids regulating reproduction. Here, we test this hypothesis by examining contaminant levels, stress and sex steroid levels, and nematode abundances in male drab treefrogs, Smilisca sordida, from lowland and montane populations in Costa Rica. We found no evidence that montane populations were more likely to possess contaminants (i.e., organochlorine, organophosphate and carbamate pesticides or benzidine and chlorophenoxy herbicides) than lowland populations. We also found no evidence of elevational differences in circulating levels of the stress hormone corticosterone, estradiol or progesterone. However, montane populations possessed lower androgen levels, hosted more nematode species, and had higher nematode abundances than lowland populations. Although these results suggested that nematodes contributed to lower androgens in montane populations, we were unable to detect a significant inverse relationship between nematode abundance and androgen level. Our results suggest that montane populations of this species are not at greater risk of exposure to contaminants or chronic stress, but implicate nematodes and compromised sex steroid levels as potential threats to montane populations.

  6. Assessing the links among environmental contaminants, endocrinology, and parasites to understand amphibian declines in montane regions of Costa Rica.

    Directory of Open Access Journals (Sweden)

    Christopher J Leary

    Full Text Available Amphibians inhabiting montane riparian zones in the Neotropics are particularly vulnerable to decline, but the reasons are poorly understood. Because environmental contaminants, endocrine disruption, and pathogens often figure prominently in amphibian declines it is imperative that we understand how these factors are potentially interrelated to affect montane populations. One possibility is that increased precipitation associated with global warming promotes the deposition of contaminants in montane regions. Increased exposure to contaminants, in turn, potentially elicits chronic elevations in circulating stress hormones that could contribute to montane population declines by compromising resistance to pathogens and/or production of sex steroids regulating reproduction. Here, we test this hypothesis by examining contaminant levels, stress and sex steroid levels, and nematode abundances in male drab treefrogs, Smilisca sordida, from lowland and montane populations in Costa Rica. We found no evidence that montane populations were more likely to possess contaminants (i.e., organochlorine, organophosphate and carbamate pesticides or benzidine and chlorophenoxy herbicides than lowland populations. We also found no evidence of elevational differences in circulating levels of the stress hormone corticosterone, estradiol or progesterone. However, montane populations possessed lower androgen levels, hosted more nematode species, and had higher nematode abundances than lowland populations. Although these results suggested that nematodes contributed to lower androgens in montane populations, we were unable to detect a significant inverse relationship between nematode abundance and androgen level. Our results suggest that montane populations of this species are not at greater risk of exposure to contaminants or chronic stress, but implicate nematodes and compromised sex steroid levels as potential threats to montane populations.

  7. Does vivianite control phosphate solubility in anoxic meadow soils?

    DEFF Research Database (Denmark)

    Walpersdorf, Eva Christine; Bender Koch, Christian; Heiberg, Lisa

    2013-01-01

    Vivianite (Fe3(PO4)2·8H2O) may precipitate in anoxic wetland soils where it may control orthophosphate (Pi) equilibrium solution concentrations at micromolar levels, and thus be of key importance in reducing excessive P from agricultural sources and eutrophication. However, vivianite equilibria...... and kinetics under in situ conditions are not fully understood and the occurrence of vivianite in wetland soils is rarely documented. In the present investigation we have monitored the temporal (November to June) variation in the pore water chemistry of a wet meadow soil (Sapric Medihemist) including...... restored. Even after 120 days following perturbation the supersaturation was still high (SIviv~6). It seems that vivianite does contribute to Pi immobilization in anoxic soil horizons, but due to slow precipitation kinetics such soils cannot maintain Pi concentrations at levels below critical thresholds...

  8. Food supply depends on seagrass meadows in the coral triangle

    International Nuclear Information System (INIS)

    Unsworth, Richard K F; Hinder, Stephanie L; Bodger, Owen G; Cullen-Unsworth, Leanne C

    2014-01-01

    The tropical seascape provides food and livelihoods to hundreds of millions of people, but the support of key habitats to this supply remains ill appreciated. For fisheries and conservation management actions to help promote resilient ecosystems, sustainable livelihoods, and food supply, knowledge is required about the habitats that help support fisheries productivity and the consequences of this for food security. This paper provides an interdisciplinary case study from the coral triangle of how seagrass meadows provide support for fisheries and local food security. We apply a triangulated approach that utilizes ecological, fisheries and market data combined with over 250 household interviews. Our research demonstrates that seagrass associated fauna in a coral triangle marine protected area support local food supply contributing at least 50% of the fish based food. This formed between 54% and 99% of daily protein intake in the area. Fishery catch was found to significantly vary with respect to village (p < 0.01) with habitat configuration a probable driver. Juvenile fish comprised 26% of the fishery catch and gear type significantly influenced this proportion (<0.05). Limited sustainability of fishery practices (high juvenile catch and a 51% decline in CPUE for the biggest fishery) and poor habitat management mean the security of this food supply has the potential to be undermined in the long-term. Findings of this study have implications for the management and assessment of fisheries throughout the tropical seascape. Our study provides an exemplar for why natural resource management should move beyond biodiversity and consider how conservation and local food security are interlinked processes that are not mutually exclusive. Seagrass meadows are under sustained threat worldwide, this study provides evidence of the need to conserve these not just to protect biodiversity but to protect food security. (letter)

  9. Drivers of methane uptake by montane forest soils in the Peruvian Andes

    Science.gov (United States)

    Jones, Sam; Diem, Torsten; Huaraca Quispe, Lidia; Cahuana, Adan; Meir, Patrick; Teh, Yit

    2016-04-01

    The exchange of methane between the soils of humid tropical forests and the atmosphere is relatively poorly documented. This is particularly true of montane settings where variations between uptake and emission of atmospheric methane have been observed. Whilst most of these ecosystems appear to function as net sinks for atmospheric methane, some act as considerable sources. In regions like the Andes, humid montane forests are extensive and a better understanding of the magnitude and controls on soil-atmosphere methane exchange is required. We report methane fluxes from upper montane cloud forest (2811 - 2962 m asl), lower montane cloud forest (1532 - 1786 m asl), and premontane forest (1070 - 1088 m asl) soils in south-eastern Peru. Between 1000 and 3000 m asl, mean annual air temperature and total annual precipitation decrease from 24 ° C and 5000 mm to 12 ° C and 1700 mm. The study region experiences a pronounced wet season between October and April. Monthly measurements of soil-atmosphere gas exchange, soil moisture, soil temperature, soil oxygen concentration, available ammonium and available nitrate were made from February 2011 in the upper and lower montane cloud forests and July 2011 in the premontane forest to June 2013. These soils acted as sinks for atmospheric methane with mean net fluxes for wet and dry season, respectively, of -2.1 (0.2) and -1.5 (0.1) mg CH4 m-2 d-1 in the upper montane forest; -1.5 (0.2) and -1.4 (0.1) mg CH4 m-2 d-1in the lower montane forest; and -0.3 (0.2) and -0.2 (0.2) mg CH4 m-2 d-1 in the premontane forest. Spatial variations among forest types were related to available nitrate and water-filled pore space suggesting that nitrate inhibition of oxidation or constraints on the diffusional supply of methane to methanotrophic communities may be important controls on methane cycling in these soils. Seasonality in methane exchange, with weaker uptake related to increased water-filled pore space and soil temperature during the wet

  10. Prognosis of accumulation value of 137SCs and 90Sr in the herbages of the main types of the Belarus Polesje meadows utilizing agrochemical properties

    International Nuclear Information System (INIS)

    Podolyak, A.G.; Bogdevich, I.M.; Ivashkova, I.I.

    2007-01-01

    On the basis of long-term stationary experience it was established that the minimum accumulation of 137Cs and 90Sr in the herbage of the waterless valley, marshed and flood types of the Belarus Polesje meadows contaminated by Chernobyl radionuclides is seen when the optimum basic agrochemical soil properties are achieved with the application of the scientifically reasonable protective measures. It was demonstrated that in the remote period of the accident for the prognosis of radionuclides contents in natural and cultural meadows herbage it is advisable to use of transfer factors (TFa, Bq/kg : kBq/square m) based on the complex agrochemical parameters - basic saturation degree (V, %) and agrochemical cultivation soils index (Iac), which take into account several soil characteristics simultaneously. This article provides the equations of linear and multiple regressions that can be used to calculate the transfer factors for 137Cs and 90Sr uptake and the herbage contamination degree for the main types of meadows of the region, which will allow one to reduce the volume of forages production (hay, green bulk) that is not adequate to the established permissible levels: Republican allowable levels of the contents of cesium-137 and strontium-90 in agricultural raw material and forages

  11. Forecasting of accumulation of Cs 137 and Sr 90 in the herbage of the main types of the Belarus Palessje meadows utilizing agrochemical soil properties

    International Nuclear Information System (INIS)

    Podolyak, A.G.; Bogdevich, I.M.; Ivashkova, I.I.

    2007-01-01

    On the basis of long-term stationary experience it was established that the minimum accumulation of Cs 137 and Sr 90 in the herbage of the waterless valley, marshed and flood types of the Belarus Palessje meadows contaminated by Chernobyl radionuclides is seen when the optimum basic agrochemical soil properties are achieved with the application of the scientifically reasonable protective measures. It was demonstrated that in the remote period of the accident for the prognosis of radionuclides contents in natural and cultural meadows herbage it is advisable to use of transfer factors (TFa, Bq/kg : kBq/m2) based on the complex agrochemical parameters - basic saturation degree (V, %) and agrochemical cultivation soils index (Iac), which take into account several soil characteristics simultaneously. This article provides the equations of linear and multiple regressions that can be used to calculate the transfer factors for Cs 137 and Sr 90 uptake and the herbage contamination degree for the main types of meadows of the region, which will allow one to reduce the volume of forages production (hay, green bulk) that is not adequate to the established permissible levels: Republican allowable levels of the contents of cesium-137 and strontium-90 in agricultural raw material and forages. (authors)

  12. Seasonal dynamics of the plant community and soil seed bank along a successional gradient in a subalpine meadow on the Tibetan Plateau.

    Directory of Open Access Journals (Sweden)

    Miaojun Ma

    Full Text Available BACKGROUND: Knowledge about how change the importance of soil seed bank and relationship between seed mass and abundance during vegetation succession is crucial for understanding vegetation dynamics. Many studies have been conducted, but their ecological mechanisms of community assembly are not fully understood. METHODOLOGY: We examined the seasonal dynamics of the vegetation and soil seed bank as well as seed size distribution along a successional gradient. We also explored the potential role of the soil seed bank in plant community regeneration, the relationship between seed mass and species abundance, and the relative importance of deterministic and stochastic processes along a successional gradient. PRINCIPAL FINDINGS: Species richness of seed bank increased (shallow layer and the total and seed density decreased (each layer and the total significantly with succession. Species richness and seed density differed significantly between different seasons and among soil depths. Seed mass showed a significant negative relationship with relative abundance in the earliest successional stage, but the relationships were not significant in later stages. Seed mass showed no relationship with relative abundance in the whole successional series in seed bank. Results were similar for both July 2005 and April 2006. CONCLUSIONS: The seed mass and abundance relationship was determined by a complex interaction between small and larger seeded species and environmental factors. Both stochastic processes and deterministic processes were important determinants of the structure of the earliest stage. The importance of seed bank decreased with succession. The restoration of abandoned farmed and grazed meadows to the species-rich subalpine meadow in Tibetan Plateau can be successfully achieved from the soil seed bank. However, at least 20 years are required to fully restore an abandoned agricultural meadow to a natural mature subalpine meadow.

  13. Bacterial biomass and DNA diversity in an alluvial meadow soil upon long-term fertilization

    NARCIS (Netherlands)

    Naumova, N.B.; Kuikman, P.J.

    2001-01-01

    The denaturing gradient gel-electrophoresis of bacterial DNA fragments and the assessment of bacterial biomass revealed changes in the diversity of the bacterial community in a meadow alluvial soil upon long-term fertilization.

  14. Screening level contaminant survey of the Sunkhaze Meadows National Wildlife Refuge

    Data.gov (United States)

    Department of the Interior — The 9,337-acre Sunkhaze Meadows National Wildlife Refuge is located in the Town of Milford, Maine. Along the refuge’s southern boundary is the former Town of Milford...

  15. Key biogeochemical factors affecting soil carbon storage in Posidonia meadows

    KAUST Repository

    Serrano, Oscar; Ricart, Aurora M.; Lavery, Paul S.; Mateo, Miguel Angel; Arias-Ortiz, Ariane; Masque, Pere; Rozaimi, Mohammad; Steven, Andy; Duarte, Carlos M.

    2016-01-01

    Biotic and abiotic factors influence the accumulation of organic carbon (C-org) in seagrass ecosystems. We surveyed Posidonia sinuosa meadows growing in different water depths to assess the variability in the sources, stocks and accumulation rates of Corg. We show that over the last 500 years, P. sinuosa meadows closer to the upper limit of distribution (at 2-4 m depth) accumulated 3- to 4-fold higher C-org stocks (averaging 6.3 kg C-org m(-2) at 3- to 4-fold higher rates (12.8 gC(org) m(-2) yr(-1) ) compared to meadows closer to the deep limits of distribution (at 6-8 m depth; 1.8 kg C-org m(-2) and 3.6 g C-org m(-2) yr(-1) . In shallower meadows, C-org stocks were mostly derived from seagrass detritus (88% in average) compared to meadows closer to the deep limit of distribution (45% on average). In addition, soil accumulation rates and fine-grained sediment content (< 0.125 mm) in shallower meadows (2.0 mm yr(-1) and 9 %, respectively) were approximately 2-fold higher than in deeper meadows (1.2 mm yr(-1) and 5 %, respectively). The C-org stocks and accumulation rates accumulated over the last 500 years in bare sediments (0.6 kg C-org m(-2) and 1.2 g C-org m(-2) yr(-1)were 3- to 11-fold lower than in P. sinuosa meadows, while fine-grained sediment content (1 %) and seagrass detritus contribution to the Corg pool (20 %) were 8- and 3-fold lower than in Posidonia meadows, respectively. The patterns found support the hypothesis that Corg storage in seagrass soils is influenced by interactions of biological (e.g., meadow productivity, cover and density), chemical (e.g., recalcitrance of Corg stocks) and physical (e.g., hydrodynamic energy and soil accumulation rates) factors within the meadow. We conclude that there is a need to improve global estimates of seagrass carbon storage accounting for biogeochemical factors driving variability within habitats.

  16. Climate and landscape drive the pace and pattern of conifer encroachment into subalpine meadows.

    Science.gov (United States)

    Lubetkin, Kaitlin C; Westerling, Anthony LeRoy; Kueppers, Lara M

    2017-09-01

    Mountain meadows have high biodiversity and help regulate stream water release following the snowmelt pulse. However, many meadows are experiencing woody plant encroachment, threatening these ecosystem services. While there have been field surveys of individual meadows and remote sensing-based landscape-scale studies of encroachment, what is missing is a broad-scale, ground-based study to understand common regional drivers, especially at high elevations, where land management has often played a less direct role. With this study, we ask: What are the climate and landscape conditions conducive to woody plant encroachment at the landscape scale, and how has historical climate variation affected tree recruitment in subalpine meadows over time? We measured density of encroaching trees across 340 subalpine meadows in the central Sierra Nevada, California, USA, and used generalized additive models (GAMs) to determine the relationship between landscape-scale patterns of encroachment and meadow environmental properties. We determined ages of trees in 30 survey meadows, used observed climate and GAMs to model the relationship between timing of recruitment and climate since the early 1900s, and extrapolated recruitment patterns into the future using downscaled climate scenarios. Encroachment was high among meadows with lodgepole pine (Pinus contorta Douglas ex Loudon var. murrayana (Balf.) Engelm.) in the immediate vicinity, at lower elevations, with physical conditions favoring strong soil drying, and with maximum temperatures above or below average. Climatic conditions during the year of germination were unimportant, with tree recruitment instead depending on a 3-yr seed production period prior to germination and a 6-yr seedling establishment period following germination. Recruitment was high when the seed production period had high snowpack, and when the seedling establishment period had warm summer maximum temperatures, high summer precipitation, and high snowpack

  17. Livestock grazing intensity affects abundance of Common shrews (Sorex araneus) in two meadows in Denmark

    OpenAIRE

    Schmidt, Niels M; Olsen, Henrik; Leirs, Herwig

    2009-01-01

    Abstract Background Current nature conservation in semi-natural grasslands often includes grazing and hay cutting, as well as the abandonment of draining. Semi-natural grassland and in particular meadows constitute important habitat type for a large number of animal species in today's fragmented and intensively cultivated landscape of Europe. Here we focus on the population characteristics of Common shrews Sorex araneus in relation to livestock grazing intensity in two wet meadows in western ...

  18. The impact of dredge-fill on Posidonia oceanica seagrass meadows: regression and patterns of recovery.

    Science.gov (United States)

    Badalamenti, Fabio; Alagna, Adriana; D'Anna, Giovanni; Terlizzi, Antonio; Di Carlo, Giuseppe

    2011-03-01

    Posidonia oceanica meadows can be severely damaged by dredge-fill operations. We report on the construction of gas pipelines that occurred between 1981 and 1993 in SW Sicily, Italy. A large portion of the meadow was mechanically removed, and the excavated trench was filled with a mosaic of substrates, ranging from sand to consolidated rock debris. Meadow loss and recovery were quantified over 7 years after the end of operations. We recorded an overall loss of 81.20 ha of meadow. Substrate strongly affected recovery as the percent cover by P. oceanica consistently increased on calcareous rubble, reaching values of 44.37 ± 3.05% in shallow sites after 7 years, whereas no significant increase occurred on other substrates. As in the Mediterranean Sea exploitation of coastal areas continues to grow with consequent impacts on P. oceanica meadows, this case study illustrates how artificial rubble-like materials could be employed to support the restoration of damaged meadows. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Natural radionuclides in meadow and pasture land in the Nordic countries

    International Nuclear Information System (INIS)

    Rosen, K.; Gutierrez Villanueva, J.-L.; Sundell-Bergman, S.

    2012-06-01

    The amount of natural radionuclides in the environment differs between the Nordic countries as shown by previous investigations and also by this study. Agricultural areas of high natural background are predominantly found in Sweden, Southern Finland and Norway while low background areas are typical for Iceland and Denmark. Thus, this study offers possibilities for studying behaviour of natural radionuclides under different conditions such as the influence of different soil types as well as the husbandry. Furthermore the areas also enable studying environmental behaviour of radium and other natural radionuclides under seemingly steady state conditions. However, migration and accumulation of natural radionuclides in cultivated soil is complex involving various processes. Thus, a long term goal of this study was to identify the implications of some of these processes by determining the soil to plant transfer for pasture land under the different conditions that prevail in the Nordic countries. The potential health hazards due to chronic ingestion of low concentrations of naturally occurring radionuclides are fairly unknown but the results of this study may provide valuable background information for assessing these radiation risks. The aim of this project has been to gain knowledge on the status of natural radionuclides in meadow and pasture land and in grassland plants in different Nordic countries and on the transfer of these radionuclides from soil/water to man via the milk/food chain (soil- meadow/pasture grass -cow-milk). Limited data are available on the mobility and the transfer of naturally occurring radionuclides in the ecosystems of the agricultural land. In addition, information concerning the concentrations in meat and dairy products is of interest for assessing exposures of humans to natural radionuclides. Soil characteristics are known to have significant impact on the mobility and uptake of natural radionuclides. Therefore, the uptake in relation to

  20. Natural radionuclides in meadow and pasture land in the Nordic countries

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, K.; Gutierrez Villanueva, J.-L.; Sundell-Bergman, S. [Swedish Univ. of Agricultural Sciences (SLU) (Sweden)] [and others

    2012-06-15

    The amount of natural radionuclides in the environment differs between the Nordic countries as shown by previous investigations and also by this study. Agricultural areas of high natural background are predominantly found in Sweden, Southern Finland and Norway while low background areas are typical for Iceland and Denmark. Thus, this study offers possibilities for studying behaviour of natural radionuclides under different conditions such as the influence of different soil types as well as the husbandry. Furthermore the areas also enable studying environmental behaviour of radium and other natural radionuclides under seemingly steady state conditions. However, migration and accumulation of natural radionuclides in cultivated soil is complex involving various processes. Thus, a long term goal of this study was to identify the implications of some of these processes by determining the soil to plant transfer for pasture land under the different conditions that prevail in the Nordic countries. The potential health hazards due to chronic ingestion of low concentrations of naturally occurring radionuclides are fairly unknown but the results of this study may provide valuable background information for assessing these radiation risks. The aim of this project has been to gain knowledge on the status of natural radionuclides in meadow and pasture land and in grassland plants in different Nordic countries and on the transfer of these radionuclides from soil/water to man via the milk/food chain (soil- meadow/pasture grass -cow-milk). Limited data are available on the mobility and the transfer of naturally occurring radionuclides in the ecosystems of the agricultural land. In addition, information concerning the concentrations in meat and dairy products is of interest for assessing exposures of humans to natural radionuclides. Soil characteristics are known to have significant impact on the mobility and uptake of natural radionuclides. Therefore, the uptake in relation to

  1. Constraints on tree seedling establishment in montane grasslands of the Valles Caldera, New Mexico

    Science.gov (United States)

    Jonathan D. Coop; Thomas J. Givnish

    2008-01-01

    Montane and subalpine grasslands are prominent, but poorly understood, features of the Rocky Mountains. These communities frequently occur below reversed tree lines on valley floors, where nightly cold air accumulation is spatially coupled with fine soil texture. We used field experiments to assess the roles of minimum temperature, soil texture, grass competition, and...

  2. Influences of climate on fire regimes in montane forests of north-western Mexico

    Science.gov (United States)

    Carl N. Skinner; Jack H. Burk; Michael G. Barbour; Ernesto Franco-Vizcaino; Scott L. Stephens

    2008-01-01

    Aim To identify the influence of interannual and interdecadal climate variation on the occurrence and extent of fires in montane conifer forests of north-western Mexico. Location This study was conducted in Jeffrey pine (Pinus jeffreyi Grev. & Balf.)- dominated mixed-conifer...

  3. Fagus dominance in Chinese montane forests : natural regeneration of Fagus lucida and Fagus hayatae var. pashanica

    NARCIS (Netherlands)

    Cao, K.F.

    1995-01-01


    Fagus species are important components of certain mesic temperate forests in the Northern Hemisphere. Of eleven Fagus species distinguished, five are found in China. Chinese beeches are restricted to the mountains of southern China. In the montane

  4. Impact of fire in two old-growth montane longleaf pine stands

    Science.gov (United States)

    John S. Kush; John C. Gilbert; Crystal Lupo; Na Zhou; Becky Barlow

    2013-01-01

    The structure of longleaf pine (Pinus palustris Mill.) forests of the Southeastern United States Coastal Plains has been the focus of numerous studies. By comparison, the forests in the mountains of Alabama and Georgia are not well understood. Less than 1 percent of longleaf pine stands found in the montane portion of longleaf’s range are considered...

  5. Cold tolerance and photosystem function in a montane red spruce population: physiological relationships with foliar carbohydrates

    Science.gov (United States)

    P.G. Shaberg; G.R. Strimbeck; G.J. Hawley; D.H. DeHayes; J.B. Shane; P.F. Murakami; T.D. Perkins; J.R. Donnelly; B.L. Wong

    2000-01-01

    Red spruce (Picea rubens Sarg.) growing in northern montane forests of eastern North America appears to be distinctive with respect to at least two aspects of winter physiology. First, red spruce attains only a modest level of midwinter cold tolerance compared to other north temperate conifers and appears barely capable of avoiding freezing injury at...

  6. Selective extraction methods for aluminium, iron and organic carbon from montane volcanic ash soils

    NARCIS (Netherlands)

    Jansen, B.; Tonneijck, F.H.; Verstraten, J.M.

    2011-01-01

    Montane volcanic ash soils contain disproportionate amounts of soil organic carbon and thereby play an often underestimated role in the global carbon cycle. Given the central role of Al and Fe in stabilizing organic matter in volcanic ash soils, we assessed various extraction methods of Al, Fe, and

  7. Morphology and sedimentation in Caribbean montane streams" examples from Jamaica and Puerto Rico

    Science.gov (United States)

    R. Ahmad; F.N. Scatena; A Gupta

    1993-01-01

    This paper presents a summary description of the morphology, sedimentation, and behaviour of the montane streams of eastern Jamaica and eastern Puerto Rico. The area is located within a 200 km wide seismically active zone of Neogene left-lateral strike-slip deformation which defines the plate boundary between the Caribbean and North American Plates. Tropical storms,...

  8. Elevational Distribution of Adult Trees and Seedlings in a Tropical Montane Transect, Southwest China

    Directory of Open Access Journals (Sweden)

    Xiaoyang Song

    2016-08-01

    Full Text Available Montane habitats are characterized by high variation of environmental factors within small geographic ranges, which offers opportunities to explore how forest assemblages respond to changes in environmental conditions. Understanding the distributional transition of adult trees and seedlings will provide insight into the fate of forest biodiversity in response to future climate change. We investigated the elevational distribution of 156 species of adult trees and 152 species of seedlings in a tropical montane forest in Xishuangbanna, southwest China. Adult trees and seedlings were surveyed within 5 replicate plots established at each of 4 elevational bands (800, 1000, 1200, and 1400 m above sea level. We found that species richness of both adult trees and seedlings changed with elevation, showing a notable decline in diversity values from 1000 to 1200 m. Tree species composition also demonstrated distinct differences between 1000 and 1200 m, marking the division between tropical seasonal rain forest (800 and 1000 m and tropical montane evergreen broad-leaved forest (1200 and 1400 m. The results suggested that soil moisture and temperature regimes were associated with elevational distribution of tree species in this region. We also observed that seedlings from certain species found at high elevations were also distributed in low-elevation zones, but no seedlings of species from low elevations were distributed in high-elevation zones. The increase in temperature and droughts predicted for this region may result in the contraction of tropical seasonal rain forest at lower elevations and a downhill shift of higher tropical montane tree species.

  9. Lithological and fluvial controls on the geomorphology of tropical montane stream channels in Puerto Rico

    Science.gov (United States)

    Andrew S. Pike; F.N. Scatena; Ellen E. Wohl

    2010-01-01

    An extensive survey and topographic analysis of fi ve watersheds draining the Luquillo Mountains in north-eastern Puerto Rico was conducted to decouple the relative infl uences of lithologic and hydraulic forces in shaping the morphology of tropical montane stream channels. The Luquillo Mountains are a steep landscape composed of volcaniclastic and igneous rocks that...

  10. Recovery of goat·damaged vegetation in an insular tropical montane forest

    Science.gov (United States)

    Paul G. Scowcroft; Robert. Hobdy

    1987-01-01

    The feral goat (Capra hircus) is an alien herbivore that has wreaked havoc in island ecosystems, including the dry, rugged, and relatively inaccessible montane koa parkland on the islands of Maui and Hawai'i. The objective of the present work was to evaluate the ability of koa parkland on Maui to recover naturally from browsing damage if...

  11. Habitat preferences of birds in a montane forest mosaic in the ...

    African Journals Online (AJOL)

    Endemic species are most closely dependent on continuous forest cover. However, some montane species did not show any clear habitat associations and thus can be viewed as local habitat generalists. This study shows that many restricted-range species (including endangered endemics) are able to live in fragmented ...

  12. Geographic, environmental and biotic sources of variation in the nutrient relations of tropical montane forests

    Science.gov (United States)

    James W. Dalling; Katherine Heineman; Grizelle Gonzalez; Rebecca Ostertag

    2016-01-01

    Tropicalmontane forests (TMF) are associated with a widely observed suite of characteristics encompassing forest structure, plant traits and biogeochemistry.With respect to nutrient relations, montane forests are characterized by slow decomposition of organic matter, high investment in below-ground biomass and poor litter quality, relative to tropical lowland forests....

  13. Influences of previous wildfires on change, resistance, and resilience to reburning in a montane southwestern landscape

    Science.gov (United States)

    Jonathan D. Coop; Lisa Holsinger; Sarah McClernan; Sean A. Parks

    2015-01-01

    Land use legacies and climate have altered fire regimes across montane forests of much of the southwestern US (Allen and others 2002), and several recent wildfires have been extremely large and severe (Dennison and others 2014). Large openings resulting from high-severity fire in former ponderosa pine (Pinus ponderosa) and mixed conifer forests may be persistent given...

  14. water quality of the high-montane Juan Cojo and El Salado's basins (Glrardota - Antioqula, Colombia)

    International Nuclear Information System (INIS)

    Gomez Marin, Ana Maria; Naranjo Fernandez, Dario; Martinez, Andres Alfonso; Gallego Suarez, Dario de Jesus

    2007-01-01

    This work is a preliminary diagnosis of the actual state of the high-montane water sources located in the Juan Cojo's and El Salado's basins of the NE side of the Aburra valley' both belong to the Girardota municipality (6 degrades 20.951' N, 75 celsius 27.199' W between 1900 and 2500 meter above sea level in the central montane chain. in order to achieve this work several samples were taken in august 10, 11, 17 and 19 of 2004. this preliminary study includes the physicochemical and microbiological evaluation of 30 sampling points. just one of the 30 sampling points exhibited absence of microbiological pollution due to fecal and total coliforms. this fact suggests bad practices in the final disposal of domestic and farming water residuals. in the other hand, the physicochemical and the ICA (water quality index) evaluation reveal that the sampled water sources exhibit typical characteristics of common low-montane ,non-polluted water sources. in other words, although pollution levels found in those water sources are not alarming, they do not exhibit the typical pollution levels found in natural high-montane waters, as they should, even we could find some sampling points with meso-eutrophic conditions

  15. Kinyongia asheorum sp n., a new montane chameleon from the Nyiro Range, northern Kenya (Squamata: Chamaeleonidae)

    Czech Academy of Sciences Publication Activity Database

    Nečas, P.; Sindaco, R.; Kořený, L.; Kopečná, J.; Malonza, P. K.; Modrý, David

    -, č. 2028 (2009), s. 41-50 ISSN 1175-5326 R&D Projects: GA ČR GA524/03/1548; GA ČR GA206/03/1544 Institutional research plan: CEZ:AV0Z60220518 Keywords : Kinyongia asheorum sp n, * new montane chameleon * Kenya Subject RIV: EG - Zoology Impact factor: 0.891, year: 2009

  16. Successional dynamics and restoration implications of a montane coniferous forest in the central Appalachians, USA

    Science.gov (United States)

    Thomas M. Schuler; Rachel J. Collins

    2002-01-01

    Central Appalachian montane red spruce (Picea rubens Sarg.) communities have been greatly reduced in extent and functional quality over the past century. This community decline has put several plant and animal species, such as the endangered Virginia northern flying squirrel (Glaucomys sabrinus fuscus Shaw), at risk from habitat...

  17. Green economy: un'occasione per le aree montane

    Directory of Open Access Journals (Sweden)

    Maria Sapone

    2013-06-01

    di rivitalizzare le aree montane. Il presente contributo rappresenta un avanzamento di studio sui temi che hanno interessato la costruzione di una rete di ecovillaggi approfondendo problematiche relative all'economia locale, al paesaggio e, più in generale, alla sostenibilità ambientale. Normal 0 14 false false false IT ZH-TW X-NONE

  18. Snowpack, fire, and forest disturbance: interactions affect montane invasions by non-native shrubs.

    Science.gov (United States)

    Stevens, Jens T; Latimer, Andrew M

    2015-06-01

    Montane regions worldwide have experienced relatively low plant invasion rates, a trend attributed to increased climatic severity, low rates of disturbance, and reduced propagule pressure relative to lowlands. Manipulative experiments at elevations above the invasive range of non-native species can clarify the relative contributions of these mechanisms to montane invasion resistance, yet such experiments are rare. Furthermore, global climate change and land use changes are expected to cause decreases in snowpack and increases in disturbance by fire and forest thinning in montane forests. We examined the importance of these factors in limiting montane invasions using a field transplant experiment above the invasive range of two non-native lowland shrubs, Scotch broom (Cytisus scoparius) and Spanish broom (Spartium junceum), in the rain-snow transition zone of the Sierra Nevada of California. We tested the effects of canopy closure, prescribed fire, and winter snow depth on demographic transitions of each species. Establishment of both species was most likely at intermediate levels of canopy disturbance, but at this intermediate canopy level, snow depth had negative effects on winter survival of seedlings. We used matrix population models to show that an 86% reduction in winter snowfall would cause a 2.8-fold increase in population growth rates in Scotch broom and a 3.5-fold increase in Spanish broom. Fall prescribed fire increased germination rates, but decreased overall population growth rates by reducing plant survival. However, at longer fire return intervals, population recovery between fires is likely to keep growth rates high, especially under low snowpack conditions. Many treatment combinations had positive growth rates despite being above the current invasive range, indicating that propagule pressure, disturbance, and climate can all strongly affect plant invasions in montane regions. We conclude that projected reductions in winter snowpack and increases in

  19. Carbon storage in the seagrass meadows of Gazi Bay, Kenya.

    Directory of Open Access Journals (Sweden)

    Michael N Githaiga

    Full Text Available Vegetated marine habitats are globally important carbon sinks, making a significant contribution towards mitigating climate change, and they provide a wide range of other ecosystem services. However, large gaps in knowledge remain, particularly for seagrass meadows in Africa. The present study estimated biomass and sediment organic carbon (Corg stocks of four dominant seagrass species in Gazi Bay, Kenya. It compared sediment Corg between seagrass areas in vegetated and un-vegetated 'controls', using the naturally patchy occurence of seagrass at this site to test the impacts of seagrass growth on sediment Corg. It also explored relationships between the sediment and above-ground Corg, as well as between the total biomass and above-ground parameters. Sediment Corg was significantly different between species, range: 160.7-233.8 Mg C ha-1 (compared to the global range of 115.3 to 829.2 Mg C ha-1. Vegetated areas in all species had significantly higher sediment Corg compared with un-vegetated controls; the presence of seagrass increased Corg by 4-6 times. Biomass carbon differed significantly between species with means ranging between 4.8-7.1 Mg C ha-1 compared to the global range of 2.5-7.3 Mg C ha-1. To our knowledge, these are among the first results on seagrass sediment Corg to be reported from African seagrass beds; and contribute towards our understanding of the role of seagrass in global carbon dynamics.

  20. Blue carbon stocks in Baltic Sea eelgrass (Zostera marina) meadows

    DEFF Research Database (Denmark)

    Rohr, Maria Emilia; Bostrom, Christoffer; Canal-Vergés, Paula

    2016-01-01

    Although seagrasses cover only a minor fraction of the ocean seafloor, their carbon sink capacity accounts for nearly one-fifth of the total oceanic carbon burial and thus play a critical structural and functional role in many coastal ecosystems. We sampled 10 eelgrass (Zostera marina) meadows....... The C-org stock integrated over the top 25 cm of the sediment averaged 627 g C m(-2) in Finland, while in Denmark the average C-org stock was over 6 times higher (4324 g Cm-2). A conservative estimate of the total organic carbon pool in the regions ranged between 6.98 and 44.9 t C ha(-1). Our results...... in Finland and 10 in Denmark to explore seagrass carbon stocks (C-org stock) and carbon accumulation rates (C-org accumulation) in the Baltic Sea area. The study sites represent a gradient from sheltered to exposed locations in both regions to reflect expected minimum and maximum stocks and accumulation...

  1. Patterns and Drivers of Scattered Tree Loss in Agricultural Landscapes: Orchard Meadows in Germany (1968-2009)

    Science.gov (United States)

    Plieninger, Tobias; Levers, Christian; Mantel, Martin; Costa, Augusta; Schaich, Harald; Kuemmerle, Tobias

    2015-01-01

    Scattered trees support high levels of farmland biodiversity and ecosystem services in agricultural landscapes, but they are threatened by agricultural intensification, urbanization, and land abandonment. This study aimed to map and quantify the decline of orchard meadows (scattered fruit trees of high nature conservation value) for a region in Southwestern Germany for the 1968 2009 period and to identify the driving forces of this decline. We derived orchard meadow loss from 1968 and 2009 aerial images and used a boosted regression trees modelling framework to assess the relative importance of 18 environmental, demographic, and socio-economic variables to test five alternative hypothesis explaining orchard meadow loss. We found that orchard meadow loss occurred in flatter areas, in areas where smaller plot sizes and fragmented orchard meadows prevailed, and in areas near settlements and infrastructure. The analysis did not confirm that orchard meadow loss was higher in areas where agricultural intensification was stronger and in areas of lower implementation levels of conservation policies. Our results demonstrated that the influential drivers of orchard meadow loss were those that reduce economic profitability and increase opportunity costs for orchards, providing incentives for converting orchard meadows to other, more profitable land uses. These insights could be taken up by local- and regional-level conservation policies to identify the sites of persistent orchard meadows in agricultural landscapes that would be prioritized in conservation efforts. PMID:25932914

  2. THE FERTILIZATION EFFECT OF PERMANENT MEADOWS WITH SPENT MUSHROM SUBSTRATE ON THE UPTAKING OF MANGANESE, COPPER AND ZINC BY THE MEADOW SWARD

    Directory of Open Access Journals (Sweden)

    Beata Wiśniewska-Kadżajan

    2013-04-01

    Full Text Available The study was conducted in the years 1999–2001 in a meadow with the following fertilizer combinations: control object (without fertilizer, NPK mineral fertilization, fertilizing with manure, manure with NPK fertilization, fertilizing with spent mushroom substrate; spent mushroom substrate with NPK fertilization. The aim of the study was to determine the effect of permanent grassland fertilization both with spent mushroom substrate and the one supplemented with NPK on the uptaking of manganese, copper and zinc by the meadow sward. After the cultivation of mushrooms, in comparison to the standard manure, the substrate used in the experiment was characterized by more than twice higher amount of manganese and zinc. However, the amount of copper in the organic materials was similar. In spite of having supplied lager amount of manganese, zinc and similar amount of copper to the mushrooms substrate, it caused the reduction of the uptake of the elements in the meadow sward. In spite of supplying larger amounts of manganese, zinc and copper the reduction of their uptaking by meadow sward was observed in comparison to manure mushroom substrate. This may be connected with a slightly alkaline reaction of the soil environment, thus limiting the uptake of the studied micronutrients.

  3. Restoration of floodplain meadows: Effects on the re-establishment of mosses

    Science.gov (United States)

    Wolski, Grzegorz J.; Harnisch, Matthias; Otte, Annette; Bomanowska, Anna; Donath, Tobias W.

    2017-01-01

    Vascular plants serve as target species for the evaluation of restoration success as they account for most of the plant species diversity and vegetation cover. Although bryophytes contribute considerably to the species diversity of meadows, they are rarely addressed in restoration projects. This project is a first step toward making recommendations for including mosses in alluvial floodplain restoration projects. The opportunity to assess the diversity and ecological requirements of mosses on floodplain meadows presented itself within the framework of a vegetation monitoring that took place in 2014 on meadows located along the northern Upper Rhine. In this area, large-scale meadow restoration projects have taken place since 1997 in both the functional and fossil floodplains. Other studies have shown that bryophytes are generally present in green hay used in restoration, providing inadvertent bryophyte introduction. We compared bryophyte communities in donor and restored communities and correlated these communities with environmental variables—taking into account that the mosses on the restoration sites possibly developed from green hay. This analysis provided insights as to which species of bryophytes should be included in future restoration projects, what diaspores should be used, and how they should be transferred. Data on bryophyte occurrence were gathered from old meadows, and from restoration sites. We found distinct differences in bryophyte composition (based on frequency) in restored communities in functional flood plains compared to donor communities. Generally, restoration sites are still characterized by a lower species-richness, with a significantly lower occurrence of rare and red listed species and a lower species-heterogeneity. In conclusion, our research establishes what mosses predominate in donor and restored alluvial meadows along the northern Upper River, and what microsite conditions favour particular species. This points the way to deliberate

  4. Decadal changes in the structure of Cymodocea nodosa seagrass meadows: Natural vs. human influences

    Science.gov (United States)

    Tuya, Fernando; Ribeiro-Leite, Luís; Arto-Cuesta, Noelia; Coca, Josep; Haroun, Ricardo; Espino, Fernando

    2014-01-01

    Seagrass meadows are deteriorating worldwide. However, numerous declines are still unreported, which avoid accurate evaluations of seagrass global trends. This is particularly relevant for the western African coast and nearby oceanic archipelagos in the eastern Atlantic. The seagrass Cymodocea nodosa is an 'ecological engineer' on shallow soft bottoms of the Canary Islands. A comparative decadal study was conducted in 21 C. nodosa seagrass meadows at Gran Canaria Island to compare the structure (shoot density, leaf length and cover) between 2003 and 2012. Overall, 11 meadows exhibited a severe regression, while 10 remained relatively stable. During this period, natural influences (sea surface temperature, Chlorophyll-a concentration and PAR light, as well as the number of storm episodes detaching seagrasses) had a low predictive power on temporal patterns in seagrass structure. In contrast, proximity from a range of human-mediated influences (e.g. the number of outfalls and ports) seem to be related to the loss of seagrass; the rate of seagrass erosion between 2003 and 2012 was significantly predicted by the number of human-mediated impacts around each meadow. This result highlights promoting management actions to conserve meadows of C. nodosa at the study region through efficient management of local impacts.

  5. The estimation of some wild flowers seed material from the natural-valuable meadow habitats

    Directory of Open Access Journals (Sweden)

    Janicka Maria

    2016-12-01

    Full Text Available The restoration of the species composition of the meadow habitats is often linked to the introduction of the typical species’ seeds. The effectiveness of that treatment requires getting the acquired detailed knowledge of the germination biology of peculiar species. Eight typical plant species of four non-forest habitats of the river valleys, representing the following types: Cnidion dubii (6440, Molinion (6410, Arrhenatherion (6510 and Festuco-Brometea (6210 were investigated. The diasporas were collected in the years 2014–2015 on the meadows of PLH 140016 protection area near Mniszew (Kozienice county, Mazovian voivodeship. The ability of seeds’ germination in the laboratory conditions was studied. It was stated that Cnidion and Molinion meadows’ species require pre-chilling to break the seeds’ dormancy, while the Arrhenatherion meadows and xerotermophilous swards do not require such treatment. The Allium angulosum, Plantago lanceolata, Achillea millefolium and Eryngium planum were characterized by high vigour and germination capability as well as the low share of dead seeds. The extremely drought in 2015 caused the decreasing in germination capability and increasing in the dead seeds’ share. The preliminary studies, presented in this paper, show that Cnidion and Molinion meadows may be most difficult to restore because of the necessity of breaking the seeds’ dormancy and higher sensitiveness for the unfavourable weather conditions during the seed ripening stage. The studies have practical significance for the works connected with the floristic diversity’ increasing of threatened communities and the restoration of the destroyed meadow habitats.

  6. Towards Detection of Cutting in Hay Meadows by Using of NDVI and EVI Time Series

    Directory of Open Access Journals (Sweden)

    Andrej Halabuk

    2015-05-01

    Full Text Available The main requirement for preserving European hay meadows in good condition is through prerequisite cut management. However, monitoring these practices on a larger scale is very difficult. Our study analyses the use of MODIS vegetation indices products, namely EVI and NDVI, to discriminate cut and uncut meadows in Slovakia. We tested the added value of simple transformations of raw data series (seasonal statistics, first difference series, compared EVI and NDVI, and analyzed optimal periods, the number of scenes and the effect of smoothing on classification performance. The first difference series transformation saw substantial improvement in classification results. The best case NDVI series classification yielded overall accuracy of 85% with balanced rates of producer’s and user’s accuracies for both classes. EVI yielded slightly lower values, though not significantly different, although user accuracy of cut meadows achieved only 67%. Optimal periods for discriminating cut and uncut meadows lay between 16 May and 4 August, meaning only seven consecutive images are enough to accurately detect cutting in hay meadows. More importantly, the 16-day compositing period seemed to be enough for detection of cutting, which would be the time span that might be hopefully achieved by upcoming on-board HR sensors (e.g., Sentinel-2.

  7. Sediment Transport Capacity and Channel Processes in a Humid Tropical Montane River - Rio Pacuare, Costa Rica

    Science.gov (United States)

    Lind, P.; McDowell, P. F.

    2017-12-01

    Investigating sediment transport capacity as well as the spatial and temporal variations of sediment flux are critical component of river research, especially for applications in resource management and conservation, hazards assessment and planning, and riverine ecology. The bedload fraction of sediment transported through montane rivers often defines channel and bed form processes. It is understood that humid tropical montane rivers are capable of producing some of the largest quantities of sediment per unit drainage area. Bedload flux reported on a few Southeast Asian humid tropical montane rivers show that bedload constituted 16-75% of the total sediment load - this is notably higher than the generally accepted 10% of a channel's sediment load. However, to date almost all of the research done on sediment transport in humid tropical systems has focused on suspended load. This study presents annual bedload transport rate estimates for six field sites distributed within 45 river kilometers (Rkm) of the montane portion of the Rio Pacuare, located in the Talamanca Mountains of Costa Rica. This research reveals that flows capable of mobilizing the D84 occur on average at least once but often multiple times a year in this river system. The Rio Pacuare has a sufficient supply of sediment to meet its high transport capacity needs. As a result, large active bars composed of imbricated boulders define channel form at moderate and low flows throughout the study area. Differences in the magnitude, as well as the spatial and temporal variations of sediment flux at each field site are discussed in relation to stream power, and annual/inter-annual precipitation patterns. A unique mix of field and remote sensing techniques were applied to address these questions and to overcome some of the challenges of tropical river research. For example, due to the large grain size and high stream energy, grain mobilization and validation of modeled shear stress requirements for transport

  8. Cellulose and cutisin decomposition in soil of Alopecuretum meadow

    Directory of Open Access Journals (Sweden)

    Zuzana Hrevušová

    2012-01-01

    Full Text Available Plant litter decomposition is a fundamental process to ecosystem functioning regulated by both abiotic and biotic factors. The aim of this study was to determine the decomposition of cellulose and protein (cutisin substrates on permanent Alopecuretum meadow under different methods of management. The treatments were following: 2 × cut, 2 × cut + NPK, 2 × mulch, 1 × cut, 1 × mulch (frequency of mowing per year and no-treated plots. Cutting or mulching was carried out in October, under the 2 × cut management also in May. In 2007–2009, cellulose and cutisin in mesh bags were placed in the soil and kept from April to October. Total mean ratios of decomposed cellulose and cutisin were 83 % and 40 % of primal substrate weight, respectively. The cellulose decomposition was affected by weather conditions, but not by applied management. The highest mean ratio of decomposed cellulose was found in 2009 (with increased amount of precipitation in May and July, the lowest in 2007. Coefficients of variation within a year and over the years were up to 22 % and 20 %, respectively. The cutisin decomposition was significantly affected by applied management in all three years. Higher rates of decomposition were noted in two times mowed treatments compared to one or not mowed treatments. Significant differences were found between years in 2× cut and 2 × cut + NPK treatments. Coefficients of variation within the year and over the years were both higher by cutisin than by cellulose samples (up to 50 and 42 %, respectively.

  9. Dugong dugon feeding in tropical Australian seagrass meadows: implications for conservation planning

    Directory of Open Access Journals (Sweden)

    Samantha J. Tol

    2016-07-01

    Full Text Available Dugongs (Dugong dugon are listed as vulnerable to extinction due to rapid population reductions caused in part by loss of seagrass feeding meadows. Understanding dugong feeding behaviour in tropical Australia, where the majority of dugongs live, will assist conservation strategies. We examined whether feeding patterns in intertidal seagrass meadows in tropical north-eastern Australia were related to seagrass biomass, species composition and/or nitrogen content. The total biomass of each seagrass species removed by feeding dugongs was measured and compared to its relative availability. Nitrogen concentrations were also determined for each seagrass species present at the sites. Dugongs consumed seagrass species in proportion to their availability, with biomass being the primary determining factor. Species composition and/or nitrogen content influenced consumption to a lesser degree. Conservation plans focused on protecting high biomass intertidal seagrass meadows are likely to be most effective at ensuring the survival of dugong in tropical north-eastern Australia.

  10. Expositions of the Botanic Garden of Petrozavodsk State University: "Рagan Meadow"

    Directory of Open Access Journals (Sweden)

    Eglacheva Arina

    2015-12-01

    Full Text Available "Pagan Meadow" - one of the business cards of Botanic Garden of PSU filled deep sense of creation and originality. Pyramidal junipers were rescued and brought to the mining sites shungit in 1999. The unique expedition was attended by students and graduate students of the Ecology-Biological Faculty. Stone maze and seids appeared in 2011 as a result of the competition landscape projects "Northern motives." Despite the initial dissociation of the two projects lined up a complete picture of the veneration of wood and stone in the history of Karelia. Consideration "Pagan Meadow" by studying upland meadows with a treelike junipers and diversity of the maze of boulders lets discuss the issues of ecology and geology.

  11. The energy balance of utilising meadow grass in Danish biogas production

    DEFF Research Database (Denmark)

    Meyer, Ane Katharina Paarup; Raju, Chitra Sangaraju; Kucheryavskiy, Sergey V.

    2015-01-01

    of meadow areas, different relevant geo-datasets, spatial analyses, and various statistical analyses. The results show that values for the energy return on energy invested (EROEI) ranging from 1.7 to 3.3 can be obtained when utilising meadow grasses in local biogas production. The total national net energy......This paper presents a study of the energy balance of utilising nature conservation biomass from meadow habitats in Danish biogas production. Utilisation of nature conservation grass in biogas production in Denmark represents an interesting perspective for enhancing nature conservation of the open...... grassland habitats, while introducing an alternative to the use of intensively cultivated energy crops as co-substrates in manure based biogas plants. The energy balance of utilising nature conservation grass was investigated by using: data collected from previous investigations on the productivity...

  12. Herbicide contamination and the potential impact to seagrass meadows in Hervey Bay, Queensland, Australia.

    Science.gov (United States)

    McMahon, Kathryn; Bengtson Nash, Susan; Eaglesham, Geoff; Müller, Jochen F; Duke, Norman C; Winderlich, Steve

    2005-01-01

    Low concentrations of herbicides (up to 70 ng l(-1)), chiefly diuron (up to 50 ng l(-1)) were detected in surface waters associated with inter-tidal seagrass meadows of Zostera muelleri in Hervey Bay, south-east Queensland, Australia. Diuron and atrazine (up to 1.1 ng g(-1) dry weight of sediment) were detected in the sediments of these seagrass meadows. Concentration of the herbicides diuron, simazine and atrazine increased in surface waters associated with seagrass meadows during moderate river flow events indicating herbicides were washed from the catchment to the marine environment. Maximum herbicide concentration (sum of eight herbicides) in the Mary River during a moderate river flow event was 4260 ng l(-1). No photosynthetic stress was detected in seagrass in this study during low river flow. However, with moderate river flow events, nearshore seagrasses are at risk of being exposed to concentrations of herbicides that are known to inhibit photosynthesis.

  13. Effects of Spring Drought on Carbon Sequestration, Evapotranspiration and Water Use Efficiency in the Songnen Meadow Steppe in Northeast China.

    Science.gov (United States)

    Gang Dong; Jixun Guo; Jiquan Chen; Ge Sun; Song Gao; et al

    2011-01-01

    Global climate change projections suggest an increasing frequency of droughts and extreme rain events in the steppes of the Eurasian region. Using the eddy covariance method, we measured carbon and water balances of a meadow steppe ecosystem in Northeast China during 2 years which had contrasting precipitation patterns in spring seasons in 2007 and 2008. The meadow...

  14. Effectiveness of turf stripping as a measure for restoring species-rich fen meadows in suboptimal hydrological conditions

    NARCIS (Netherlands)

    Hoek, van der D.; Heijmans, M.M.P.D.

    2007-01-01

    Most species-rich fen meadows in nature reserves in The Netherlands are acidified due to weaker upwelling of base-rich groundwater. The present study investigated whether and why turf stripping combined with superficial drainage might promote the long-term recovery of such meadows and restore the

  15. Business Ethics in Third World Countries. A Romanian Representative Case: Roşia Montană

    Directory of Open Access Journals (Sweden)

    Iuliana Zaharia

    2010-03-01

    Full Text Available Roşia Montană case became representative by its complexity, considering the interaction of the economic with other social sectors on one hand, and on the other hand, considering the context of a economy on the globalization edge in a South-eastern European country 'rebuilt' after 1989 and in a permanent 'reform' of 20 years, representative by the way the economics dictates to the politics, sealing the road to sustainable disaster in an "era of sustainable development”. Edifying symbol of the times that we live at the beginning of the XXIst century, maintaing the focus on the Romanian opened wound Roşia Montană is equivalent to a live lesson about the survival or the collapse of the (human ecosystem. About the morality as a reality of another order than that of biological life and as a sine qua non condition of the humanity preservation.Note: The aggregate term Third World was challenged as misleading starting with the Cold War period, because it got various meanings depending on different points of view: 1. it was used to define during the Cold War the countries that remained non-aligned or not moving at all with either capitalism and NATO (which along with its allies represented the First World or communism and the Soviet Union (which along with its allies represented the Second World; 2. it has also a completely different definition according to human development index – the term Third World, when used today generally denotes countries that have not "developed" to the same levels as OECD countries, and which are thus in the process of "developing"; 3. in the 1980s, economist Peter Bauer offered a competing definition for the term Third World, claiming that the attachment of Third World status to a particular country was not based on any stable economic or political criteria, and was a mostly arbitrary process. The large diversity of countries that were considered to be part of the Third World, from Indonesia to Afghanistan, ranged

  16. Topographic and spatial controls of palm species distributions in a montane rain forest, southern Ecuador

    DEFF Research Database (Denmark)

    Svenning, J.-C.; Harlev, D.; Sørensen, M.M.

    2009-01-01

    The northern Andes harbour a flora that is as species-rich or even richer than the 18-times larger lowland Amazon basin. Gaining an understanding of how the high species richness of the Andean region is generated and maintained is therefore of particular interest. Environmental sorting due......). Mantel tests and indicator species analysis showed that both topography and spatial location imposed strong controls on palm species distributions at the study site. Our results suggest that species distributions in the studied montane forest landscape were partly determined by the species' habitat...... distributions at the study site. Other factors must also be involved, notably wind-exposure and hydrology, as discussed for lowland palm communities. Our results show that to understand plant community assembly in the tropical montane forests of the Andes it is too simple to focus just on environmental sorting...

  17. Using Seismic Refraction and Ground Penetrating Radar (GPR) to Characterize the Valley Fill in Beaver Meadows, Rocky Mountain National Park

    Science.gov (United States)

    Kramer, N.; Harry, D. L.; Wohl, E. E.

    2010-12-01

    This study is one of the first to use near surface geophysical techniques to characterize the subsurface stratigraphy in a high alpine, low gradient valley with a past glacial history and to obtain a preliminary grasp on the impact of Holocene beaver activity. Approximately 1 km of seismic refraction data and 5 km of GPR data were collected in Beaver Meadows, Rocky Mountain National Park. An asymmetric wedge of sediment ranging in depth from 0-20 m transverse to the valley profile was identified using seismic refraction. Complementary analysis of the GPR data suggests that the valley fill can be subdivided into till deposited during the Pleistocene glaciations and alluvium deposited during the Holocene. Two main facies were identified in the GPR profiles through pattern recognition. Facie Fd, which consists of chaotic discontinuous reflectors with an abundance of diffractions, is interpreted to be glacial till. Facie Fc, which is a combination of packages of complex slightly continuous reflectors interfingered with continuous horizontal to subhorizontal reflectors, is interpreted to be post-glacial alluvium and includes overbank, pond and in-channel deposits. Fc consistently overlies Fd throughout the study area and is no more than 7 m thick in the middle of the valley. The thickness of Holocene sedimentation (beaver dams, a high abundance of fine sediment including silts and clays, historical records of beavers, and the name "Beaver Meadows" all suggest that Holocene beaver activity played a large role in sediment accumulation at this site, despite the lack of surficial relict beaver dams containing wood.

  18. Tropical montane forest conversion affects spatial and temporal nitrogen dynamics in Kenyan headwater catchment

    Science.gov (United States)

    Jacobs, Suzanne; Weeser, Björn; Breuer, Lutz; Butterbach-Bahl, Klaus; Guzha, Alphonce; Rufino, Mariana

    2017-04-01

    Deforestation and land use change (LUC) are often stated as major contributors to changes in water quality, although other catchment characteristics such as topography, geology and climate can also play a role. Understanding how stream water chemistry is affected by LUC is essential for sustainable water management and land use planning. However, there is often a lack of reliable data, especially in less studied regions such as East Africa. This study focuses on three sub-catchments (27-36 km2) with different land use types (natural forest, smallholder agriculture and tea/tree plantations) nested in a 1023 km2 headwater catchment in the Mau Forest Complex, Kenya's largest closed-canopy indigenous tropical montane forest. In the past decades approx. 25% of the natural forest was lost due to land use change. We studied seasonal, diurnal and spatial patterns of total dissolved nitrogen (TDN), nitrate (NO3-N) and dissolved organic nitrogen (DON) using a combination of high-resolution in-situ measurements, bi-weekly stream water samples and spatial sampling campaigns. Multiple linear regression analysis of the spatial data indicates that land use shows a strong influence on TDN and nitrate, while DON is more influenced by precipitation. Highest TDN and nitrate concentrations are found in tea plantations, followed by smallholder agriculture and natural forest. This ranking does not change throughout the year, though concentrations of TDN and nitrate are respectively 27.6 and 25.4% lower in all catchments during the dry season. Maximum Overlap Discrete Wavelet Transform (MODWT) analysis of the high resolution nitrate data revealed a seasonal effect on diurnal patterns in the natural forest catchment, where the daily peak shifts from early morning in the wet season to mid-afternoon in the dry season. The smallholder and tea catchment do not exhibit clear diurnal patterns. The results suggest that land use affects dissolved nitrogen concentrations, leading to higher N

  19. Historical, observed, and modeled wildfire severity in montane forests of the Colorado Front Range.

    Science.gov (United States)

    Sherriff, Rosemary L; Platt, Rutherford V; Veblen, Thomas T; Schoennagel, Tania L; Gartner, Meredith H

    2014-01-01

    Large recent fires in the western U.S. have contributed to a perception that fire exclusion has caused an unprecedented occurrence of uncharacteristically severe fires, particularly in lower elevation dry pine forests. In the absence of long-term fire severity records, it is unknown how short-term trends compare to fire severity prior to 20th century fire exclusion. This study compares historical (i.e. pre-1920) fire severity with observed modern fire severity and modeled potential fire behavior across 564,413 ha of montane forests of the Colorado Front Range. We used forest structure and tree-ring fire history to characterize fire severity at 232 sites and then modeled historical fire-severity across the entire study area using biophysical variables. Eighteen (7.8%) sites were characterized by low-severity fires and 214 (92.2%) by mixed-severity fires (i.e. including moderate- or high-severity fires). Difference in area of historical versus observed low-severity fire within nine recent (post-1999) large fire perimeters was greatest in lower montane forests. Only 16% of the study area recorded a shift from historical low severity to a higher potential for crown fire today. An historical fire regime of more frequent and low-severity fires at low elevations (historically and continue to be so today. Thinning treatments at higher elevations of the montane zone will not return the fire regime to an historic low-severity regime, and are of questionable effectiveness in preventing severe wildfires. Based on present-day fuels, predicted fire behavior under extreme fire weather continues to indicate a mixed-severity fire regime throughout most of the montane forest zone. Recent large wildfires in the Front Range are not fundamentally different from similar events that occurred historically under extreme weather conditions.

  20. Savonarola at the stake: the rise and fall of Roy Meadow.

    Science.gov (United States)

    Kaplan, Robert

    2008-06-01

    The aim of this paper is to describe the role of prominent paediatrician Professor Sir Roy Meadow in the controversy surrounding the diagnosis of Munchausen Syndrome by Proxy (MSBP) in mothers accused of murdering their children. The MSBP saga is a further chapter of an era of moral panic that started several decades ago with repressed memory therapy, satanic ritual abuse and multiple personalities. The fall of medieval sage Savonarola is an apt analogy for the fate of Roy Meadow. The history of medicine is rife with figures who become their own authority and rule by force of personality.

  1. On the Origin of Pantepui montane biotas: A Perspective Based on the Phylogeny of Aulacorhynchus toucanets.

    Directory of Open Access Journals (Sweden)

    Elisa Bonaccorso

    Full Text Available To understand the origin of Pantepui montane biotas, we studied the biogeography of toucanets in the genus Aulacorhynchus. These birds are ideal for analyzing historical relationships among Neotropical montane regions, given their geographic distribution from Mexico south to Bolivia, including northern Venezuela (Cordillera de la Costa, and the Pantepui. Analyses were based on molecular phylogenies using mitochondrial and nuclear DNA sequences. Topology tests were applied to compare alternative hypotheses that may explain the current distribution of Aulacorhynchus toucanets, in the context of previous hypotheses of the origin of Pantepui montane biotas. Biogeographic reconstructions in RASP and Lagrange were used to estimate the ancestral area of the genus, and an analysis in BEAST was used to estimate a time framework for its diversification. A sister relationship between the Pantepui and Andes+Cordillera de la Costa was significantly more likely than topologies indicating other hypothesis for the origin of Pantepui populations. The Andes was inferred as the ancestral area for Aulacorhynchus, and the group has diversified since the late Miocene. The biogeographic patterns found herein, in which the Andes are the source for biotas of other regions, are consistent with those found for flowerpiercers and tanagers, and do not support the hypothesis of the geologically old Pantepui as a source of Neotropical montain diversity. Based on the high potential for cryptic speciation and isolation of Pantepui populations, we consider that phylogenetic studies of additional taxa are important from a conservation perspective.

  2. A MCDM Analysis of the Roşia Montană Gold Mining Project

    Directory of Open Access Journals (Sweden)

    Adriana Mihai

    2015-06-01

    Full Text Available The need and estimated utility for a structured analysis of the Roşia Montană gold exploitation project have been palpable in the Romanian public sphere during the last 15 years and there is a vast amount of conflicting information and opinions on the benefits and risks involved. This article provides a comprehensive decision analysis of the Roşia Montană project. Over 100 documents from the past years have been gathered regarding the Roşia Montană mining project, which cover the main official, formal and less formal documents covering the case and produced by a wide range of stakeholders. These were then analyzed while designing a multi-criteria tree including the relevant perspectives under which the most commonly discussed four alternatives were analyzed. The result of this can be translated into a valuable recommendation for the mining company and for the political decision-makers. If these stakeholders want the continuation of the project and its acceptance by civil society, the key challenge is to increase the transparency of the process and improve the credibility and legal aspects; if these aspects cannot be met, the decision-makers need to pay attention to the alternatives available for a sustainable development in the area.

  3. Stream Nitrogen Inputs Reflect Groundwater Across a Snowmelt-Dominated Montane to Urban Watershed.

    Science.gov (United States)

    Hall, Steven J; Weintraub, Samantha R; Eiriksson, David; Brooks, Paul D; Baker, Michelle A; Bowen, Gabriel J; Bowling, David R

    2016-02-02

    Snowmelt dominates the hydrograph of many temperate montane streams, yet little work has characterized how streamwater sources and nitrogen (N) dynamics vary across wildland to urban land use gradients in these watersheds. Across a third-order catchment in Salt Lake City, Utah, we asked where and when groundwater vs shallow surface water inputs controlled stream discharge and N dynamics. Stream water isotopes (δ(2)H and δ(18)O) reflected a consistent snowmelt water source during baseflow. Near-chemostatic relationships between conservative ions and discharge implied that groundwater dominated discharge year-round across the montane and urban sites, challenging the conceptual emphasis on direct stormwater inputs to urban streams. Stream and groundwater NO3(-) concentrations remained consistently low during snowmelt and baseflow in most montane and urban stream reaches, indicating effective subsurface N retention or denitrification and minimal impact of fertilizer or deposition N sources. Rather, NO3(-) concentrations increased 50-fold following urban groundwater inputs, showing that subsurface flow paths potentially impact nutrient loading more than surficial land use. Isotopic composition of H2O and NO3(-) suggested that snowmelt-derived urban groundwater intercepted NO3(-) from leaking sewers. Sewer maintenance could potentially mitigate hotspots of stream N inputs at mountain/valley transitions, which have been largely overlooked in semiarid urban ecosystems.

  4. Species turnover in tropical montane forest avifauna links to climatic correlates

    Directory of Open Access Journals (Sweden)

    Chi-Feng Tsai

    2015-01-01

    Full Text Available We examined avifauna richness and composition in Taiwan’s tropical montane forests, and compared to historical records dated 22 years ago. A richness attrition of 44 species caused a discrepancy of 30.2%, and an estimated yearly turnover of 2.2%. More resident species that were narrower or lower in elevation distribution, insectivores/omnivores, small to medium-sized, forest/open-field dwelling, and canopy/ground foragers, vanished; whereas piscivores, carnivores, riparian- and shrub-dwellers, ground and mid-layer foragers, and migrants suffered by higher proportions. Occurrence frequencies of persistent species remained constant but varied among ecological groups, indicating an increased homogeneity for smaller-sized insectivores/omnivores dwelling in the forest canopy, shrub, or understory. While the overall annual temperature slightly increased, a relatively stable mean temperature was replaced by an ascending trend from the mid-1990s until 2002, followed by a cooling down. Mean maximum temperatures increased but minimums decreased gradually over years, resulting in increasing temperature differences up to over 16 °C. This accompanied an increase of extreme typhoons affecting Taiwan or directly striking these montane forests during the last decade. These results, given no direct human disturbances were noted, suggest a link between the species turnover and recent climate change, and convey warning signs of conservation concerns for tropical montane assemblages.

  5. Mediating Water Temperature Increases Due to Livestock and Global Change in High Elevation Meadow Streams of the Golden Trout Wilderness

    Science.gov (United States)

    Nusslé, Sébastien; Matthews, Kathleen R.; Carlson, Stephanie M.

    2015-01-01

    Rising temperatures due to climate change are pushing the thermal limits of many species, but how climate warming interacts with other anthropogenic disturbances such as land use remains poorly understood. To understand the interactive effects of climate warming and livestock grazing on water temperature in three high elevation meadow streams in the Golden Trout Wilderness, California, we measured riparian vegetation and monitored water temperature in three meadow streams between 2008 and 2013, including two “resting” meadows and one meadow that is partially grazed. All three meadows have been subject to grazing by cattle and sheep since the 1800s and their streams are home to the imperiled California golden trout (Oncorhynchus mykiss aguabonita). In 1991, a livestock exclosure was constructed in one of the meadows (Mulkey), leaving a portion of stream ungrazed to minimize the negative effects of cattle. In 2001, cattle were removed completely from two other meadows (Big Whitney and Ramshaw), which have been in a “resting” state since that time. Inside the livestock exclosure in Mulkey, we found that riverbank vegetation was both larger and denser than outside the exclosure where cattle were present, resulting in more shaded waters and cooler maximal temperatures inside the exclosure. In addition, between meadows comparisons showed that water temperatures were cooler in the ungrazed meadows compared to the grazed area in the partially grazed meadow. Finally, we found that predicted temperatures under different global warming scenarios were likely to be higher in presence of livestock grazing. Our results highlight that land use can interact with climate change to worsen the local thermal conditions for taxa on the edge and that protecting riparian vegetation is likely to increase the resiliency of these ecosystems to climate change. PMID:26565706

  6. Geochemistry of Mine Waste and Mill Tailings, Meadow Deposits, Streambed Sediment, and General Hydrology and Water Quality for the Frohner Meadows Area, Upper Lump Gulch, Jefferson County, Montana

    Science.gov (United States)

    Klein, Terry L.; Cannon, Michael R.; Fey, David L.

    2004-01-01

    Frohner Meadows, an area of low-topographic gradient subalpine ponds and wetlands in glaciated terrane near the headwaters of Lump Gulch (a tributary of Prickly Pear Creek), is located about 15 miles west of the town of Clancy, Montana, in the Helena National Forest. Mining and ore treatment of lead-zinc-silver veins in granitic rocks of the Boulder batholith over the last 120 years from two sites (Frohner mine and the Nellie Grant mine) has resulted in accumulations of mine waste and mill tailings that have been distributed downslope and downstream by anthropogenic and natural processes. This report presents the results of an investigation of the geochemistry of the wetlands, streams, and unconsolidated-sediment deposits and the hydrology, hydrogeology, and water quality of the area affected by these sources of ore-related metals. Ground water sampled from most shallow wells in the meadow system contained high concentrations of arsenic, exceeding the Montana numeric water-quality standard for human health. Transport of cadmium and zinc in ground water is indicated at one site near Nellie Grant Creek based on water-quality data from one well near the creek. Mill tailings deposited in upper Frohner Meadow contribute large arsenic loads to Frohner Meadows Creek; Nellie Grant Creek contributes large arsenic, cadmium, and zinc loads to upper Frohner Meadows. Concentrations of total-recoverable cadmium, copper, lead, and zinc in most surface-water sites downstream from the Nellie Grant mine area exceeded Montana aquatic-life standards. Nearly all samples of surface water and ground water had neutral to slightly alkaline pH values. Concentrations of arsenic, cadmium, lead, and zinc in streambed sediment in the entire meadow below the mine waste and mill tailings accumulations are highly enriched relative to regional watershed-background concentrations and exceed consensus-based, probable-effects concentrations for streambed sediment at most sites. Cadmium, copper, and

  7. Investigating The Relationship Between Structural Geology and Wetland Loss Near Golden Meadow, Louisiana By Utilizing 3D Seismic Reflection and Well Log Data

    Science.gov (United States)

    Johnston, A. S.; Zhang, R.; Gottardi, R.; Dawers, N. H.

    2017-12-01

    Wetland loss is one of the greatest environmental and economic threats in the deltaic plain of the Gulf Coast. This loss is controlled by subsidence, sea level rise, decreased sediment supply rates, movement along normal faults, salt tectonics, fluid extraction related to oil, gas and water exploration, and compaction. However, the interplay and feedback between these different processes are still poorly understood. In this study, we investigate the role of active faulting and salt tectonics on wetland loss in an area located between Golden Meadow and Leeville, Louisiana. Using industry 3D seismic and well log data, we investigate key segments of the Golden Meadow fault zone and map shallow faults that overlie the Leeville salt dome, to compare those fault planes with areas of wetland loss and subsidence. Faults were mapped to a depth of 1200 m, and well logs were tied to the upper 180 m of the seismic data to make accurate projections of the faults to the surface. Preliminary results highlight a graben structure south of a segment of the Golden Meadow fault. Well log and published data from shallow borings reveal a thicker Holocene accumulation at the center of the graben, up to 45 m than on the flanks of the graben. The location of this graben spatially correlates with Catfish Lake, and part of it overlies salt adjacent to the main fault surface. Bayou Lafourche, the main distributary channel of the Lafourche lobe of the Mississippi River delta complex, appears to have its path controlled by faults. Bayou Lafourche changes orientation and flows parallel to, and on the downthrown side of, two radial faults associated with the Leeville salt dome. These preliminary results indicate that there is a relationship between surface geomorphology and subsurface structures that, at least in part, exert a control on wetland loss in southern Louisiana.

  8. Thematic trip: "Save Roşia MontanÄă"

    Science.gov (United States)

    Eugenia, Marcu

    2015-04-01

    The name Roşia Montană, situated in Transylvania, became well known after a Romanian-Canadian company, Roşia Montană Gold Company (RMGC), obtained the concession license on exploitation for gold and silver minerals in the Roşia Montană area. The project consists of opening the largest surface gold mines in Europe using cyanide, which will include four open pits and a processing plant for gold and silver in The Roşia Valley and a tailings facility with an area of 367 hectares in the Corna Valley. One of the main fears is related to a possible ecological accident like the one in Baia Mare in 2000, when a tailing facility dam break led to cyanide pollution of Tisa and Danube rivers that resulted in the death of 1,200 tons of fish and contamination of water resources for 2 million people. This thematic trip is important for the scientific preparation of students and an opportunity to educate them in the spirit of environmental protection. The training and education of students will require assimilation and understanding, actively and consciously, using the knowledge acquired during the compulsory curriculum and training skills. REASON: The continuous degradation of the environment is a major crisis due to human intervention in nature, and the proposed Roşia Montană mining project will continue this trend. The company proposes to extract gold from mines by using the gold separation technique using cyanide, a process that involves destroying a total area of 16 km² which includes 5 mountains, 7 churches, 11 cemeteries and the ruins of Alburnus Maior Citadel, as well as creating pollution that would last for hundreds of years. The extraction of gold from low-grade ores using cyanide processes was estimated to result in a worldwide emission of 45,300 tons of hydrogen cyanide. Environmental education for a healthy life has children as target group, because they are the trustees and beneficiaries of tomorrow's natural resources and can influence the attitudes of

  9. New Tools to Identify the Location of Seagrass Meadows: Marine Grazers as Habitat Indicators

    KAUST Repository

    Hays, Graeme C.; Alcoverro, Teresa; Christianen, Marjolijn J. A.; Duarte, Carlos M.; Hamann, Mark; Macreadie, Peter I.; Marsh, Helene D.; Rasheed, Michael A.; Thums, Michele; Unsworth, Richard K. F.; York, Paul H.; Esteban, Nicole

    2018-01-01

    and there has been a call from 122 scientists across 28 countries for more work to manage, protect and monitor seagrass meadows (http://www.bbc.com/news/science-environment-37606827). Emerging from the 12th International Seagrass Biology Workshop, held

  10. The effects of drainage on groundwater quality and plant species distribution in stream valley meadows

    NARCIS (Netherlands)

    Grootjans, A.P.; Diggelen, R. van; Wassen, M.J.; Wiersinga, W.A.

    1988-01-01

    Conditions in fen meadows in Dutch stream valleys are influenced by both deep (Ca2+-rich) and shallow (Ca2+-poor) groundwater flows. The distribution patterns of phreatophytic (groundwater-influenced) plant species showed distinct relationships with the distribution of different groundwater types.

  11. Stream channel designs for riparian and wet meadow rangelands in the southwestern United States

    Science.gov (United States)

    Roy Jemison; Daniel G. Neary

    2000-01-01

    Inappropriate land uses have degraded wetland and riparian ecosystems throughout the Southwestern United States. In 1996, the Cibola National Forest in New Mexico implemented a channel relocation project, as part of a road improvement project, to determine the feasibility of restoring wet meadow and riparian ecosystems degraded by inappropriately located roads and...

  12. Effect of abandonment and plant classification on carbohydrate reserves of meadow plants

    Czech Academy of Sciences Publication Activity Database

    Janeček, Štěpán; Lanta, Vojtěch; Klimešová, Jitka; Doležal, Jiří

    2010-01-01

    Roč. 13, č. 2 (2010), s. 243-251 ISSN 1435-8603 R&D Projects: GA ČR GA526/09/0963; GA ČR(CZ) GA526/06/0723 Institutional research plan: CEZ:AV0Z60050516 Keywords : carbohydrates * meadow * abandonment Subject RIV: EF - Botanics Impact factor: 2.409, year: 2010

  13. Diversity of lowland hay meadows and pastures in Western and Central Europe

    NARCIS (Netherlands)

    Rodríguez-Rojo, Maria Pilar; Jiménez-Alfaro, Borja; Jandt, Ute; Bruelheide, Helge; Rodwell, John S.; Schaminée, Joop H.J.; Perrin, Philip M.; Kacki, Zygmunt; Willner, Wolfgang; Fernández-González, Federico; Chytrý, Milan

    2017-01-01

    Questions: Which are the main vegetation types of lowland hay meadows and pastures in Western and Central Europe? What are the main environmental gradients that drive patterns of species composition? Is it possible to classify these grasslands to phytosociological alliances that reflect management

  14. Effects of grazing intensity on small mammal population ecology in wet meadows

    DEFF Research Database (Denmark)

    Schmidt, Niels Martin; Olsen, Henrik; Bildsøe, Mogens

    2005-01-01

    Livestock grazing is common management practice in wet grasslands. However, knowledge of its effects on small mammals is limited. We studied the influence of grazing intensity on small mammals in general and field voles Microtus agrestis in particular in two Danish wet meadows, 1998-2000. General...

  15. Soil CO2 efflux in three wet meadow ecosystems with different C and N status

    Czech Academy of Sciences Publication Activity Database

    Zemanová, K.; Čížková, Hana; Šantrůčková, H.

    Suppl.S, č. 9 (2008), s. 49-55 ISSN 1585-8553 Institutional research plan: CEZ:AV0Z60870520; CEZ:AV0Z60660521 Keywords : wet meadow * soil CO2 efflux * eutrophication Subject RIV: EH - Ecology, Behaviour Impact factor: 0.898, year: 2008

  16. Invertebrates of Meadow Creek, Union County, Oregon, and their use as food by trout.

    Science.gov (United States)

    Carl E. McLemore; William R. Meehan

    1988-01-01

    From 1976 to 1980, invertebrates were collected three times each year from several reaches of Meadow Creek in eastern Oregon. Five sampling methods were used: benthos, drift, sticky traps, water traps, and fish stomachs. A total of 372 taxa were identified, of which 239 were used as food by rainbow trout (steelhead; Salmo gairdneri Richardson). Of...

  17. Pyrenean meadows in Natura 2000 network: grass production and plant biodiversity conservation

    Energy Technology Data Exchange (ETDEWEB)

    Reine, R.; Barrantes, O.; Chocarro, C.; Juarez, A.; Broca, A.; Maestro, M.; Ferrer, C.

    2014-06-01

    In semi-natural mountain meadows, yield and forage quality must be reconciled with plant biodiversity conservation. This study was performed to analyze the relationships between these three parameters. To quantify plant biodiversity and pastoral value (PV), phyto sociological inventories were performed in 104 semi-natural meadows in the Central Spanish Pyrenees included in the Natura 2000 network. Forage yields were calculated and forage samples were analyzed for relative feed value (RFV). We identified two main types of meadows: (i) those that had more intensive management, relatively close to farm buildings, with little or no slope, dominated by grasses, with low plant biodiversity, high PV and yield, but low forage quality and (ii) those that had less intensive management, distant from farm buildings, on slopes, richer in other forbs, with high plant biodiversity and forage quality, but low PV and yield. Conservation policies should emphasize less intensive management practices to maintain plant diversity in the semi-natural meadows in the Pyrenees. The widespread view that other forbs have low nutritional value should be revised in future research. These species often are undervalued by the PV method, because their nutritional quality, digestibility and intake are poorly understood. (Author)

  18. Pyrenean meadows in Natura 2000 network: grass production and plant biodiversity conservation

    Directory of Open Access Journals (Sweden)

    Ramón Reiné

    2014-02-01

    Full Text Available In semi-natural mountain meadows, yield and forage quality must be reconciled with plant biodiversity conservation. This study was performed to analyze the relationships between these three parameters. To quantify plant biodiversity and pastoral value (PV, phytosociological inventories were performed in 104 semi-natural meadows in the Central Spanish Pyrenees included in the Natura 2000 network. Forage yields were calculated and forage samples were analyzed for relative feed value (RFV. We identified two main types of meadows: (i those that had “more intensive management,” relatively close to farm buildings, with little or no slope, dominated by grasses, with low plant biodiversity, high PV and yield, but low forage quality and (ii those that had “less intensive management,” distant from farm buildings, on slopes, richer in “other forbs”, with high plant biodiversity and forage quality, but low PV and yield. Conservation policies should emphasize less intensive management practices to maintain plant diversity in the semi-natural meadows in the Pyrenees. The widespread view that “other forbs” have low nutritional value should be revised in future research. These species often are undervalued by the PV method, because their nutritional quality, digestibility and intake are poorly understood.

  19. Meadow fragmentation and reproductive output of the S.E. Asian seagrass Enhalus acoroides

    NARCIS (Netherlands)

    Vermaat, J.E.; Rollon, R.N.; Lacap, C.D.A.; Billot, C.; Alberto, F.; Nacorda, H.M.E.; Wiegman, F.; Terrados, J.T.

    2004-01-01

    Flower and fruit production of the abundant, tall, long-lived, dioecious, surface-pollinating seagrass species Enhalus acoroides (L.) Royle were estimated at seven sites in the reef flats off Bolinao (NW Luzon, The Philippines) featuring different fragmentation of the seagrass meadows. Fragmentation

  20. Extent and reasons for meadows in South Bohemia becoming unsuitable for orchids

    Czech Academy of Sciences Publication Activity Database

    Štípková, Z.; Kindlmann, Pavel

    2015-01-01

    Roč. 5, č. 2 (2015), s. 142-147 ISSN 1805-0174 R&D Projects: GA ČR GB14-36098G Institutional support: RVO:67179843 Keywords : extinction * meadows * terrestrial orchids * South Bohemia Subject RIV: EF - Botanics

  1. At home on foreign meadows: the reintroduction of two Maculineae butterfly species

    NARCIS (Netherlands)

    Wynhoff, I.

    2001-01-01

    Maculinea butterflies live as obligate parasites of specific Myrmica host ants in meadow and heathland habitat maintained by low intensity landuse. Changes in agriculture caused the decline and extinction of many populations. In The Netherlands,

  2. Seagrass meadows globally as a coupled social-ecological system: implications for human wellbeing.

    Science.gov (United States)

    Cullen-Unsworth, Leanne C; Nordlund, Lina Mtwana; Paddock, Jessica; Baker, Susan; McKenzie, Len J; Unsworth, Richard K F

    2014-06-30

    Seagrass ecosystems are diminishing worldwide and repeated studies confirm a lack of appreciation for the value of these systems. In order to highlight their value we provide the first discussion of seagrass meadows as a coupled social-ecological system on a global scale. We consider the impact of a declining resource on people, including those for whom seagrass meadows are utilised for income generation and a source of food security through fisheries support. Case studies from across the globe are used to demonstrate the intricate relationship between seagrass meadows and people that highlight the multi-functional role of seagrasses in human wellbeing. While each case underscores unique issues, these examples simultaneously reveal social-ecological coupling that transcends cultural and geographical boundaries. We conclude that understanding seagrass meadows as a coupled social-ecological system is crucial in carving pathways for social and ecological resilience in light of current patterns of local to global environmental change. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Soil nematodes in alpine meadows of the Tatra National Park (Slovak Republic)

    Czech Academy of Sciences Publication Activity Database

    Háněl, Ladislav

    2017-01-01

    Roč. 54, č. 1 (2017), s. 48-67 ISSN 0440-6605 R&D Projects: GA ČR(CZ) GA14-09231S Institutional support: RVO:60077344 Keywords : soil nematodes * diversity * maturity * soil food web * alpine meadow Subject RIV: EH - Ecology, Behaviour OBOR OECD: Ecology Impact factor: 0.472, year: 2016

  4. Changes in biomass allocation in species rich meadow after abandonment: Ecological strategy or allometry?

    Czech Academy of Sciences Publication Activity Database

    Bartušková, Alena; Doležal, Jiří; Janeček, Štěpán; Lanta, V.; Klimešová, Jitka

    2015-01-01

    Roč. 17, č. 5 (2015), s. 379-387 ISSN 1433-8319 R&D Projects: GA ČR GB14-36079G Institutional support: RVO:67985939 Keywords : Biomass allocation * species-rich meadow * abandonment Subject RIV: EF - Botanics Impact factor: 3.578, year: 2015

  5. The effects of matrix structure on movement decisions of meadow voles (Microtus pennsylvanicus)

    Science.gov (United States)

    Robin E. Russell; Robert K. Swihart; Bruce A. Craig

    2007-01-01

    The composition of the landscape between patches (the matrix) can have important effects on movement rates that potentially outweigh the effects of patch size and isolation. We conducted a small-scale experiment with radiocollared meadow voles (Microtus pennsylvanicus) to quantify the effects of matrix habitat on movement behavior of voles. Habitat...

  6. New Tools to Identify the Location of Seagrass Meadows: Marine Grazers as Habitat Indicators

    KAUST Repository

    Hays, Graeme C.

    2018-02-21

    Seagrasses are hugely valuable to human life, but the global extent of seagrass meadows remains unclear. As evidence of their value, a United Nations program exists (http://data.unep-wcmc.org/datasets/7) to try and assess their distribution and there has been a call from 122 scientists across 28 countries for more work to manage, protect and monitor seagrass meadows (http://www.bbc.com/news/science-environment-37606827). Emerging from the 12th International Seagrass Biology Workshop, held in October 2016, has been the view that grazing marine megafauna may play a useful role in helping to identify previously unknown seagrass habitats. Here we describe this concept, showing how detailed information on the distribution of both dugongs (Dugong dugon) and green sea turtles (Chelonia mydas) obtained, for example, by aerial surveys and satellite tracking, can reveal new information on the location of seagrass meadows. We show examples of how marine megaherbivores have been effective habitat indicators, revealing major, new, deep-water seagrass meadows and offering the potential for more informed estimates of seagrass extent in tropical and sub-tropical regions where current information is often lacking.

  7. 76 FR 14984 - Sunkhaze Meadows National Wildlife Refuge, Penobscot, Kennebec, and Waldo Counties, ME, and...

    Science.gov (United States)

    2011-03-18

    ..., wildlife observation and photography, and environmental education and interpretation. We will review and... Sunkhaze Meadows NWR and Carlton Pond WPA. We will conduct the environmental review of this project and..., including American woodcock, red-winged blackbird, and bobolink. The Sandy Stream Unit is mainly comprised...

  8. 78 FR 37363 - Endangered and Threatened Wildlife and Plants; Listing Determination for the New Mexico Meadow...

    Science.gov (United States)

    2013-06-20

    ... species is an endangered or threatened species based on whether we find that it is in danger of extinction...), threats, and limiting factors in the context of determining viability and risk of extinction for the... future threats (causes and effects) facing the New Mexico meadow jumping mouse. Because data in these...

  9. Restoration potential of sedge meadows in hand-cultivated soybean fields in northeastern China

    Science.gov (United States)

    Wang, Guodong; Middleton, Beth; Jiang, Ming

    2013-01-01

    Sedge meadows can be difficult to restore from farmed fields if key structural dominants are missing from propagule banks. In hand-cultivated soybean fields in northeastern China, we asked if tussock-forming Carex and other wetland species were present as seed or asexual propagules. In the Sanjiang Plain, China, we compared the seed banks, vegetative propagules (below-ground) and standing vegetation of natural and restored sedge meadows, and hand-cultivated soybean fields in drained and flooded conditions. We found that important wetland species survived cultivation as seeds for some time (e.g. Calamogrostis angustifolia and Potamogeton crispus) and as field weeds (e.g. C. angustifolia and Phragmites australis). Key structural species were missing in these fields, for example, Carex meyeriana. We also observed that sedge meadows restored without planting or seeding lacked tussock-forming sedges. The structure of the seed bank was related to experimental water regime, and field environments of tussock height, thatch depth, and presence of burning as based on Nonmetric Multidimensional Scaling analysis. To re-establish the structure imposed by tussock sedges, specific technologies might be developed to encourage the development of tussocks in restored sedge meadows.

  10. Charcterization of meadow ecosystems based on watershed and valley segment/reach scale characteristics [chapter 7

    Science.gov (United States)

    Wendy Trowbridge; Jeanne C. Chambers; Dru Germanoski; Mark L. Lord; Jerry R. Miller; David G. Jewett

    2011-01-01

    Great Basin riparian meadows are highly sensitive to both natural and anthropogenic disturbance. As detailed in earlier chapters, streams in the central Great Basin have a natural tendency to incise due to their geomorphic history (Miller and others 2001, 2004). Anthropogenic disturbances, including overgrazing by livestock, mining activities, and roads in the valley...

  11. Habitat edges affect patterns of artificial nest predation along a wetland-meadow boundary

    Czech Academy of Sciences Publication Activity Database

    Suvorov, P.; Svobodová, J.; Albrecht, Tomáš

    2014-01-01

    Roč. 59, č. 1 (2014), s. 91-96 ISSN 1146-609X R&D Projects: GA ČR GA206/06/0851 Institutional support: RVO:68081766 Keywords : Artificial nest * Ecotonal effect * Habitat fragmentation * Nest predation * Wetland meadow Subject RIV: EG - Zoology Impact factor: 1.617, year: 2014

  12. Carbon stores from a tropical seagrass meadow in the midst of anthropogenic disturbance.

    Science.gov (United States)

    Rozaimi, Mohammad; Fairoz, Mohammad; Hakimi, Tuan Mohamad; Hamdan, Nur Hidayah; Omar, Ramlan; Ali, Masni Mohd; Tahirin, Siti Aishah

    2017-06-30

    Seagrass meadows provide important carbon sequestration services but anthropogenic activities modify the natural ecosystem and inevitably lower carbon storage capacity. The tropical mixed-species meadows in the Sungai Pulai Estuary (Johor, Malaysia) are impacted by such activities. In this study, we provide baseline estimates for carbon stores analysed from sediment cores. In sediment depths up to 100cm, organic (OC) and inorganic carbon (IC) stores were 43-101MgCha -1 and 46-83MgCha -1 , respectively, and are in the lower end of global average values. The bulk of OC (53-98%) originated from seston suggesting that the meadows had low capacity to retain seagrass-derived organic matter. The species factor resulted in some variability in OC stores but did not appear to influence IC values. The low carbon stores in the meadow may be a direct result of sediment disturbances but natural biogeochemical processes are not discounted as possible causal factors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. MANAGING AND RESTORING UPLAND RIPARIAN MEADOWS IN THE CENTRAL GREAT BASIN

    Science.gov (United States)

    Riparian meadow ecosystems in upland watersheds are of local and regional importance in the Great Basin. Covering only 1-3% of the total land area, these ecosystems contain a disproportionally large percentage of the region's biodiversity. Stream incision, due to natural and anth...

  14. Food for Pollinators: Quantifying the Nectar and Pollen Resources of Urban Flower Meadows.

    Science.gov (United States)

    Hicks, Damien M; Ouvrard, Pierre; Baldock, Katherine C R; Baude, Mathilde; Goddard, Mark A; Kunin, William E; Mitschunas, Nadine; Memmott, Jane; Morse, Helen; Nikolitsi, Maria; Osgathorpe, Lynne M; Potts, Simon G; Robertson, Kirsty M; Scott, Anna V; Sinclair, Frazer; Westbury, Duncan B; Stone, Graham N

    2016-01-01

    Planted meadows are increasingly used to improve the biodiversity and aesthetic amenity value of urban areas. Although many 'pollinator-friendly' seed mixes are available, the floral resources these provide to flower-visiting insects, and how these change through time, are largely unknown. Such data are necessary to compare the resources provided by alternative meadow seed mixes to each other and to other flowering habitats. We used quantitative surveys of over 2 million flowers to estimate the nectar and pollen resources offered by two exemplar commercial seed mixes (one annual, one perennial) and associated weeds grown as 300m2 meadows across four UK cities, sampled at six time points between May and September 2013. Nectar sugar and pollen rewards per flower varied widely across 65 species surveyed, with native British weed species (including dandelion, Taraxacum agg.) contributing the top five nectar producers and two of the top ten pollen producers. Seed mix species yielding the highest rewards per flower included Leontodon hispidus, Centaurea cyanus and C. nigra for nectar, and Papaver rhoeas, Eschscholzia californica and Malva moschata for pollen. Perennial meadows produced up to 20x more nectar and up to 6x more pollen than annual meadows, which in turn produced far more than amenity grassland controls. Perennial meadows produced resources earlier in the year than annual meadows, but both seed mixes delivered very low resource levels early in the year and these were provided almost entirely by native weeds. Pollen volume per flower is well predicted statistically by floral morphology, and nectar sugar mass and pollen volume per unit area are correlated with flower counts, raising the possibility that resource levels can be estimated for species or habitats where they cannot be measured directly. Our approach does not incorporate resource quality information (for example, pollen protein or essential amino acid content), but can easily do so when suitable data

  15. Cattle grazing and its long-term effects on sedge meadows

    Science.gov (United States)

    Middleton, Beth

    2004-01-01

    Most people think that wetlands are temporary, that they fill in by natural processes, and eventually become dry land. Some of these outdated ideas have come from the way that this subject has been covered in introductory textbooks in schools (Gibson, 1996). From these texts, we learned incorrectly that over time a lake fills with sediment or organic matter to become a wetland, which dries out to support shrubs and trees, and eventually it is no longer a wetland (Middleton, 1999; Middleton and others, 2004). These old ideas of how vegetation changes (succession) are no longer accepted. Wetland succession should be thought of as a cycle, with natural disturbance driving the changes, depending on the needs of the species. Succession is not something that changes a wetland into something that is not a wetland (Egler, 1978; van der Valk, 1981; Middleton and others, 1991; Klinger, 1996; Middleton, 1999).As an example of how disturbance changes wetlands, I have studied sedge meadows that have become invaded by shrubs after cattle (Bos sp.) have grazed them, in the Lodi Marsh State Natural Area, Wisconsin. Cattle disturbances allowed shrubs to invade sedge meadows, but the cattle also grazed on the shrubs, which kept them small. After the cows were removed, the plant species changed in the sedge meadow from the original sedges (fig. 1), to sedges mixed with growing small shrubs, and eventually to tall shrubs with very small amounts of sedge, called “shrub carr” (Middleton, 2002a). Even though there has been a succession of plant types, the meadows, which began as wetlands, have remained wetlands. The settlers originally found the sedge meadows to be open “sedge” lands and not shrubby. The settlers cut the sedges by hand to feed the cattle. Whitetailed deer (Odocoileus virginianus), though probably not bison (Bison bison), grazed these sedge meadows (Middleton 2002a).Subsequent studies have explored methods to control invasive shrubs to restore the biodiversity of

  16. English Water Meadows: historic relics or focus for environmental management and inter-disciplinary research?

    Science.gov (United States)

    Cook, Hadrian

    2015-04-01

    Irrigated water meadows are found across Europe, from southern Scandinavia to Spain and in the Alpine regions and Italy. While the practice of engineering 'floated' meadow land for deliberate irrigation on hillsides and floodplains is widespread and ancient, since about 1600 AD the practice was widely adopted on floodplains in southern England where they improved the timing and productivity of grazing land and produced hay crops. They also became a part of English consciousness through art and literature. To some, water meadows are a relic of an agrarian past, to others they are the object of a range of foci for conservation, education, sustainable grass production, community engagement and recent research suggests water returned from meadow irrigation is beneficial to river water quality. Historically floodplain 'bedwork' water meadows grew from, and were integral in, the farming system of 'Wessex' involving sheep which produced dung for arable land and later supporting dairy and beef production, as well as hay. Where systems remain, this is largely due to the whim of individuals, the outcome of agri-environmental schemes. Water meadows may be managed by public, voluntary or private sector bodies. What is needed is a fresh look at how land owners, or communities, might micro-target them for heritage, habitat and grassland management. There are therefore interesting questions concerning their future: Who might invest in their restoration and maintenance? How might they be integrated into commercial farming? Are they of sufficient interest to restore en masse to become (once more) a major feature of the English chalk stream valleys? Do they provide a way into academic and public perception, combining environmental science, history, cultural heritage and environmental management? How might restoration and management become vehicles for public engagement? While each of these questions represents a major topic for discussion, this paper is an attempt to consolidate

  17. Deterioration of eelgrass, Zostera marina L., meadows by water pollution in Seto Inland Sea, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Tamaki, Hitoshi; Tokuoka, Makoto; Nishijima, Wataru; Terawaki, Toshinobu; Okada, Mitsumasa

    2002-11-01

    Survival of transplanted Zostera marina L. (eelgrass) and environmental conditions (water quality, bottom sediments, sedimentation on leaves and flow regime) were studied concurrently in the center, edge, and at the outside of a eelgrass meadow located in a eutrophic coastal zone in northern Hiroshima Bay, Seto Inland Sea, Japan. Eelgrass transplants at the outside of the meadow declined significantly, whereas those at the center were consistently well established. Silt content in the bottom sediments at the outside was higher than that at the center. The sediment was oxic from the surface to 2 cm deep at the center, whereas those at the edge and the outside were reductive almost from the surface. The sediment characteristics typical in eutrophic water seemed to be a factor responsible for the deterioration of eelgrass meadows. Although suspended solid concentrations in the water columns were almost the same, the amount of sediments deposited on leaves of eelgrass at the outside was higher than that at the center of the meadow. The amount of the deposition at the outside seems to be enough to inhibit photosynthesis; i.e. photosynthetic photon flux density (PPFD) available for eelgrass was only 36% of that without any deposition. The deposition in the center, however, was small enough to allow 84% of the original PPFD. Flow rates, determined at 30 cm above the bottom, a half height of average eelgrass, suggested that the rate at the outside was not enough to remove deposited sediments from the surface of eelgrass leaves. Thus, the large amount of sediment deposition caused by water pollution and/or eutrophication seemed to be another factor to inhibit the survival of eelgrass at the outside edge of the meadow.

  18. Deterioration of eelgrass, Zostera marina L., meadows by water pollution in Seto Inland Sea, Japan

    International Nuclear Information System (INIS)

    Tamaki, Hitoshi; Tokuoka, Makoto; Nishijima, Wataru; Terawaki, Toshinobu; Okada, Mitsumasa

    2002-01-01

    Survival of transplanted Zostera marina L. (eelgrass) and environmental conditions (water quality, bottom sediments, sedimentation on leaves and flow regime) were studied concurrently in the center, edge, and at the outside of a eelgrass meadow located in a eutrophic coastal zone in northern Hiroshima Bay, Seto Inland Sea, Japan. Eelgrass transplants at the outside of the meadow declined significantly, whereas those at the center were consistently well established. Silt content in the bottom sediments at the outside was higher than that at the center. The sediment was oxic from the surface to 2 cm deep at the center, whereas those at the edge and the outside were reductive almost from the surface. The sediment characteristics typical in eutrophic water seemed to be a factor responsible for the deterioration of eelgrass meadows. Although suspended solid concentrations in the water columns were almost the same, the amount of sediments deposited on leaves of eelgrass at the outside was higher than that at the center of the meadow. The amount of the deposition at the outside seems to be enough to inhibit photosynthesis; i.e. photosynthetic photon flux density (PPFD) available for eelgrass was only 36% of that without any deposition. The deposition in the center, however, was small enough to allow 84% of the original PPFD. Flow rates, determined at 30 cm above the bottom, a half height of average eelgrass, suggested that the rate at the outside was not enough to remove deposited sediments from the surface of eelgrass leaves. Thus, the large amount of sediment deposition caused by water pollution and/or eutrophication seemed to be another factor to inhibit the survival of eelgrass at the outside edge of the meadow

  19. A physical framework for evaluating net effects of wet meadow restoration on late summer streamflow

    Science.gov (United States)

    Grant, G.; Nash, C.; Selker, J. S.; Lewis, S.; Noël, P.

    2017-12-01

    Restoration of degraded wet meadows that develop on upland valley floors is intended to achieve a range of ecological benefits. A widely cited benefit is the potential for meadow restoration to augment late-season streamflow; however, there has been little field data demonstrating increased summer flows following restoration. Instead, the hydrologic consequences of restoration have typically been explored using coupled groundwater and surface water flow models at instrumented sites. The expected magnitude and direction of change provided by models has, however, been inconclusive. Here, we assess the streamflow benefit that can be obtained by wet meadow restoration using a parsimonious, physically-based approach. We use a one-dimensional linearized Boussinesq equation with a superimposed solution for changes in storage due to groundwater upwelling and and explicitly calculate evapotranspiration using the White Method. The model accurately predicts water table elevations from field data in the Middle Fork John Day watershed in Oregon, USA. The full solution shows that while raising channel beds can increase total water storage via increases in water table elevation in upland valley bottoms, the contributions of both lateral and longitudinal drainage from restored floodplains to late summer streamflow are undetectably small, while losses in streamflow due to greater transpiration, lower hydraulic gradients, and less drainable pore volume are substantial. Although late-summer streamflow increases should not be expected as a direct result of wet meadow restoration, these approaches offer benefits for improving the quality and health of riparian and meadow vegetation that would warrant considering such measures, even at the cost of increased water demand and reduced streamflow.

  20. Shrimp burrow in tropical seagrass meadows: An important sink for litter

    Science.gov (United States)

    Vonk, Jan Arie; Kneer, Dominik; Stapel, Johan; Asmus, Harald

    2008-08-01

    The abundance, burrow characteristics, and in situ behaviour of the burrowing shrimps Neaxius acanthus (Decapoda: Strahlaxiidae) and Alpheus macellarius (Decapoda: Alpheidae) were studied to quantify the collection of seagrass material, to identify the fate of this collected material, and to determine the importance of these burrowing crustaceans in the nutrient (nitrogen and phosphorus) cycling of two tropical seagrass meadows on Bone Batang, South Sulawesi, Indonesia. Alpheus macellarius harvested 0.70 g dry weight (DW) burrow -1 d -1 seagrass material, dominantly by active cutting of fresh seagrass leaves. Neaxius acanthus collected 1.66 g DW burrow -1 d -1, mainly detached leaves which floated past the burrow opening. The A. macellarius and N. acanthus communities together collected in their burrows an amount of seagrass leaf material corresponding to more than 50% of the leaf production in the meadows studied. The crustacean species studied might therefore fulfil an important function in the nutrient cycling of tropical meadows. In the burrow most of the collected material is shredded into pieces. The burrows of both species had special chambers which serve as a storage for seagrass leaf material. Neaxius acanthus incorporated most of the material into the burrow wall lining, which is made of small sediment particles and macerated seagrass leaves. Phosphate concentrations measured in N. acanthus burrows compared with pore-water and water-column concentrations suggests that a substantial amount of the seagrass material undergoes decomposition in the burrows. Oxygen levels measured in these water bodies are indicative for a possible exchange of water between the burrow and its surroundings, most likely supported by the shrimps irrigating their burrows. By collecting leaf material in their burrows, nutrients that are otherwise lost from the seagrass meadow associated with detached leaves and leaf fragments carried away in the water column, are maintained in the

  1. Cuticular waxes in alpine meadow plants: climate effect inferred from latitude gradient in Qinghai-Tibetan Plateau.

    Science.gov (United States)

    Guo, Yanjun; Guo, Na; He, Yuji; Gao, Jianhua

    2015-09-01

    Alpine meadow ecosystems are susceptible to climate changes. Still, climate impact on cuticular wax in alpine meadow plants is poorly understood. Assessing the variations of cuticular wax in alpine meadow plants across different latitudes might be useful for predicting how they may respond to climate change. We studied nine alpine meadows in a climate gradient in the east side of Qinghai-Tibetan Plateau, with mean annual temperature ranging from -7.7 to 3.2°C. In total, 42 plant species were analyzed for cuticular wax, averaged 16 plant species in each meadow. Only four plant species could be observed in all sampling meadows, including Kobresia humilis,Potentilla nivea,Anaphalis lacteal, and Leontopodium nanum. The amounts of wax compositions and total cuticular wax in the four plant species varied among sampling meadows, but no significant correlation could be observed between them and temperature, precipitation, and aridity index based on plant species level. To analyze the variations of cuticular wax on community level, we averaged the amounts of n-alkanes, aliphatic acids, primary alcohols, and total cuticular wax across all investigated plant species in each sampling site. The mean annual temperature, mean temperature in July, and aridity index were significantly correlated with the averaged amounts of wax compositions and total cuticular wax. The average chain length of n-alkanes in both plant and soil linearly increased with increased temperature, whereas reduced with increased aridity index. No significant correlation could be observed between mean annual precipitation and mean precipitation from June to August and the cuticular wax amounts and average chain length. Our results suggest that the survival of some alpine plants in specific environments might be depended on their abilities in adjusting wax deposition on plant leaves, and the alpine meadow plants as a whole respond to climate change, benefiting the stability of alpine meadow ecosystem.

  2. Seasonal variations in carbon dioxide exchange in an alpine wetland meadow on the Qinghai-Tibetan Plateau

    Directory of Open Access Journals (Sweden)

    L. Zhao

    2010-04-01

    Full Text Available Alpine wetland meadow could functions as a carbon sink due to it high soil organic content and low decomposition. However, the magnitude and dynamics of carbon stock in alpine wetland ecosystems are not well quantified. Therefore, understanding how environmental variables affect the processes that regulate carbon fluxes in alpine wetland meadow on the Qinghai-Tibetan Plateau is critical. To address this issue, Gross Primary Production (GPP, Ecosystem Respiration (Reco, and Net Ecosystem Exchange (NEE were examined in an alpine wetland meadow using the eddy covariance method from October 2003 to December 2006 at the Haibei Research Station of the Chinese Academy of Sciences. Seasonal patterns of GPP and Reco were closely associated with leaf area index (LAI. The Reco showed a positive exponential to soil temperature and relatively low Reco occurred during the non-growing season after a rain event. This result is inconsistent with the result observed in alpine shrubland meadow. In total, annual GPP were estimated at 575.7, 682.9, and 630.97 g C m−2 in 2004, 2005, and 2006, respectively. Meanwhile, the Reco were equal to 676.8, 726.4, 808.2 g C m−2, and thus the NEE were 101.1, 44.0 and 173.2 g C m−2. These results indicated that the alpine wetland meadow was a moderately source of carbon dioxide (CO2. The observed carbon dioxide fluxes in the alpine wetland meadow were higher than other alpine meadow such as Kobresia humilis meadow and shrubland meadow.

  3. Projected range contractions of European protected oceanic montane plant communities: focus on climate change impacts is essential for their future conservation.

    Science.gov (United States)

    Hodd, Rory L; Bourke, David; Skeffington, Micheline Sheehy

    2014-01-01

    Global climate is rapidly changing and while many studies have investigated the potential impacts of this on the distribution of montane plant species and communities, few have focused on those with oceanic montane affinities. In Europe, highly sensitive bryophyte species reach their optimum occurrence, highest diversity and abundance in the north-west hyperoceanic regions, while a number of montane vascular plant species occur here at the edge of their range. This study evaluates the potential impact of climate change on the distribution of these species and assesses the implications for EU Habitats Directive-protected oceanic montane plant communities. We applied an ensemble of species distribution modelling techniques, using atlas data of 30 vascular plant and bryophyte species, to calculate range changes under projected future climate change. The future effectiveness of the protected area network to conserve these species was evaluated using gap analysis. We found that the majority of these montane species are projected to lose suitable climate space, primarily at lower altitudes, or that areas of suitable climate will principally shift northwards. In particular, rare oceanic montane bryophytes have poor dispersal capacity and are likely to be especially vulnerable to contractions in their current climate space. Significantly different projected range change responses were found between 1) oceanic montane bryophytes and vascular plants; 2) species belonging to different montane plant communities; 3) species categorised according to different biomes and eastern limit classifications. The inclusion of topographical variables in addition to climate, significantly improved the statistical and spatial performance of models. The current protected area network is projected to become less effective, especially for specialised arctic-montane species, posing a challenge to conserving oceanic montane plant communities. Conservation management plans need significantly

  4. Projected range contractions of European protected oceanic montane plant communities: focus on climate change impacts is essential for their future conservation.

    Directory of Open Access Journals (Sweden)

    Rory L Hodd

    Full Text Available Global climate is rapidly changing and while many studies have investigated the potential impacts of this on the distribution of montane plant species and communities, few have focused on those with oceanic montane affinities. In Europe, highly sensitive bryophyte species reach their optimum occurrence, highest diversity and abundance in the north-west hyperoceanic regions, while a number of montane vascular plant species occur here at the edge of their range. This study evaluates the potential impact of climate change on the distribution of these species and assesses the implications for EU Habitats Directive-protected oceanic montane plant communities. We applied an ensemble of species distribution modelling techniques, using atlas data of 30 vascular plant and bryophyte species, to calculate range changes under projected future climate change. The future effectiveness of the protected area network to conserve these species was evaluated using gap analysis. We found that the majority of these montane species are projected to lose suitable climate space, primarily at lower altitudes, or that areas of suitable climate will principally shift northwards. In particular, rare oceanic montane bryophytes have poor dispersal capacity and are likely to be especially vulnerable to contractions in their current climate space. Significantly different projected range change responses were found between 1 oceanic montane bryophytes and vascular plants; 2 species belonging to different montane plant communities; 3 species categorised according to different biomes and eastern limit classifications. The inclusion of topographical variables in addition to climate, significantly improved the statistical and spatial performance of models. The current protected area network is projected to become less effective, especially for specialised arctic-montane species, posing a challenge to conserving oceanic montane plant communities. Conservation management plans need

  5. Floral diversity, composition and distribution in a montane wetland in hogsback, the eastern cape province, south africa

    International Nuclear Information System (INIS)

    Omar, M.Y.; Tol, J.J.V.; Maroyi, A.

    2016-01-01

    The objective of this study was to evaluate plant species diversity, composition and distribution in a montane wetland in Hogsback, Eastern Cape province, South Africa. Twenty four circular plots with radius of 2m were established between March and August 2013 within Hogsback montane wetland. Within each sample plot, the habitat information and species present were recorded including Braun-Blanquet cover-abundance values for all species present in the plot. A total of 41 species belonging to 19 families and 36 genera were recorded. Of the documented species, 7.3% were exotic and endemic to South Africa, indicating diversity and dynamic nature of Hogsback montane wetland flora. Plant families with the highest number of species were: Poaceae (11 species), Asteraceae (six species), Onagraceae and Cyperaceae (three species each) and Lamiaceae with two species. The low number of exotic plant species recorded in Hogsback wetland (three species in total) indicates limited anthropogenic influences. Unique species recorded in Hogsback montane wetland were three species that are endemic to South Africa, namely, Alchemilla capensis Thunb., Helichrysum rosum (P.J. Bergius) Lees and Lysimachia nutans Nees. Five main floristic associations were identified from the Hierarchical Cluster Analysis. The Canonical Correspondence Analysis (CCA) indicated that edaphic factors, particularly area covered with water, erosion category, organic matter content and water table depth were the most important environmental variables measured accounting for the vegetation pattern present in the Hogsback montane wetland. Montane wetlands have a relatively low species richness characterised by unique species compositions which are distinctive and habitat specific. (author)

  6. Interaction between Posidonia oceanica meadows upper limit and hydrodynamics of four Mediterranean beaches

    Science.gov (United States)

    De Muro, Sandro; Ruju, Andrea; Buosi, Carla; Porta, Marco; Passarella, Marinella; Ibba, Angelo

    2017-04-01

    Posidonia oceanica meadow is considered to play an important role in the coastal geomorphology of Mediterranean beach systems. In particular, the importance of the meadow in protecting the coastline from erosion is well-recognized. Waves are attenuated by greater friction across seagrass meadows, which have the capacity to reduce water flow and therefore increase sediment deposition and accumulation as well as beach stability. The P. oceanica meadow upper limit usually occurs within the most dynamic zone of the beach system. Considering the great attention paid in the literature to the connection between the growth of P. oceanica and coastal hydrodynamics (Infantes et al., 2009; Vacchi et al., 2014; De Muro et al., 2016, 2017), this study aims at extending the previous work by investigating the combined influence of hydrodynamic parameters (e.g., wave-induced main currents and wave orbital velocity at the bottom) and different types of sea bottom (e.g., soft sediment, rocky substrates) on the position of the upper limit of the P. oceanica meadow. We applied this approach to 4 Mediterranean beach systems located on the Sardinian coastline (3 on the South and 1 on the North) and characterized by a wide range of orientations and incoming wave conditions. On these beaches, the extension of the P. oceanica meadows and the bathymetry have been obtained through detailed surveying campaigns and aerial photo analysis. In addition, high spatial resolution wave hydrodynamics have been reconstructed by running numerical simulations with Delft 3D. Offshore wave climate has been reconstructed by using measured datasets for those beaches that have a nearby buoy whose dataset is representative of the incoming wave conditions for that particular stretch of coast. Whereas, for those beaches with no availability of a representative measured dataset, wave climate has been analyzed from the NOAA hindcast dataset. From the whole range of incoming wave directions in deep waters, we

  7. Leaf litter decomposition rates increase with rising mean annual temperature in Hawaiian tropical montane wet forests

    Directory of Open Access Journals (Sweden)

    Lori D. Bothwell

    2014-12-01

    Full Text Available Decomposing litter in forest ecosystems supplies nutrients to plants, carbon to heterotrophic soil microorganisms and is a large source of CO2 to the atmosphere. Despite its essential role in carbon and nutrient cycling, the temperature sensitivity of leaf litter decay in tropical forest ecosystems remains poorly resolved, especially in tropical montane wet forests where the warming trend may be amplified compared to tropical wet forests at lower elevations. We quantified leaf litter decomposition rates along a highly constrained 5.2 °C mean annual temperature (MAT gradient in tropical montane wet forests on the Island of Hawaii. Dominant vegetation, substrate type and age, soil moisture, and disturbance history are all nearly constant across this gradient, allowing us to isolate the effect of rising MAT on leaf litter decomposition and nutrient release. Leaf litter decomposition rates were a positive linear function of MAT, causing the residence time of leaf litter on the forest floor to decline by ∼31 days for each 1 °C increase in MAT. Our estimate of the Q10 temperature coefficient for leaf litter decomposition was 2.17, within the commonly reported range for heterotrophic organic matter decomposition (1.5–2.5 across a broad range of ecosystems. The percentage of leaf litter nitrogen (N remaining after six months declined linearly with increasing MAT from ∼88% of initial N at the coolest site to ∼74% at the warmest site. The lack of net N immobilization during all three litter collection periods at all MAT plots indicates that N was not limiting to leaf litter decomposition, regardless of temperature. These results suggest that leaf litter decay in tropical montane wet forests may be more sensitive to rising MAT than in tropical lowland wet forests, and that increased rates of N release from decomposing litter could delay or prevent progressive N limitation to net primary productivity with climate warming.

  8. ¿Quién fue Lluís Montané i Mollfulleda?

    OpenAIRE

    Balius i Juli, Ramon

    2006-01-01

    Lluís Montané i Mollfulleda, nacido en Sant Celoni en 1905, era un artista integral, enmarcado en las corrientes novecentistas y mediterranistas que se sustentan en la tradición clásica del mundo griego. Estudió en la Escuela de Bellas Artes de Barcelona (Llotja) entre 1921 y 1927, aunque antes, muy joven, trabajó durante tres años en el taller del escultor Eusebi Arnau (1864-1933). En la Llotja su segundo maestro, después del profesor de primer curso, Parera, fue Antoni Alsina i Amils (1864-...

  9. A new montane species of Philautus (Amphibia: Anura: Rhacophoridae) from western Sarawak, Malaysia, Borneo.

    Science.gov (United States)

    Dehling, J Maximilian; Dehling, Matthias

    2013-01-01

    A new species of Philautus is described from western Sarawak. The new species was collected in lower montane forest in two national parks in Sarawak and recorded from another park. It differs from its congeners by a unique combination of morphological characters, including a long, acuminate snout, long legs, and comparatively extensive toe webbing. The advertisement call of the new species differs from all calls of other species that have been analyzed so far. Comparison of the mitochondrial 16S rRNA gene sequence corroborates its distinct specific status.

  10. Grazing exclusion increases soil CO2 emission during the growing season in alpine meadows on the Tibetan Plateau

    Science.gov (United States)

    Guo, Na; Wang, Aidong; Allan Degen, A.; Deng, Bin; Shang, Zhanhuan; Ding, Luming; Long, Ruijun

    2018-02-01

    Soil CO2 emission is a key part of the terrestrial carbon cycle. Grazing exclusion by fencing is often considered a beneficial grassland management option to restore degraded grassland, but its effect on soil CO2 emission on the northeastern Tibetan Plateau is equivocal and is the subject of this study. Using a closed static chamber, we measured diurnal soil CO2 flux weekly from July, 2008, to April, 2009, in response to grazing and grazing exclusion in the alpine meadow and alpine shrub meadow. Concomitantly, soil temperature was measured at depths of 5 cm, 10 cm, 15 cm and 20 cm with digital temperature sensors. It emerged that: 1) non-grazed grasslands emitted more soil CO2 than grazed grasslands over the growing season; 2) the alpine shrub meadow emitted more soil CO2 than the alpine meadow; the annual cumulative soil CO2 emissions of alpine meadow and alpine shrub meadow were 241.5-326.5 g C/m2 and 429.0-512.5 g C/m2, respectively; 3) seasonal patterns were evident with more soil CO2 flux in the growing than in the non-growing season; and 4) the diurnal soil CO2 flux exhibited a single peak across all sampling sites. In addition, soil CO2 flux was correlated positively with soil temperature at 5 cm, but not at the other depths. We concluded that grazing exclusion enhanced soil CO2 emission over the growing season, and decreased carbon sequestration of alpine meadow and alpine shrub meadow on the northeastern Tibetan Plateau. Since an increase in soil temperature increased soil CO2 flux, global warming could have an effect on soil CO2 emission in the future.

  11. Organo-mineral interactions promote greater soil organic carbon stability under aspen in semi-arid montane forests in Utah

    Science.gov (United States)

    Van Miegroet, H.; Roman Dobarco, M.

    2014-12-01

    Forest species influence soil organic carbon (SOC) storage through litter input, which in interaction with soil microclimate, texture and mineralogy, lead to different SOC stabilization and storage patterns. We sampled mineral soil (0-15 cm) across the ecotone between aspen (Populus tremuloides) and mixed conifers stands (Abies lasiocarpa and Pseudotsuga menziesii) in semi-arid montane forests from Utah, to investigate the influence of vegetation vs. site characteristics on SOC stabilization, storage and chemistry. SOC was divided into light fraction (LF), mineral-associated SOC in the silt and clay fraction (MoM), and a dense subfraction > 53 μm (SMoM) using wet sieving and electrostatic attraction. SOC decomposability and solubility was derived from long term laboratory incubations and hot water extractions (HWE). Fourier transform infrared spectroscopy (FTIR) was used to study differences in chemical functional groups in LF and MoM. Vegetation cover did not affect SOC storage (47.0 ± 16.5 Mg C ha-1), SOC decomposability (cumulative CO2-C release of 93.2 ± 65.4 g C g-1 C), or SOC solubility (9.8 ± 7.2 mg C g-1 C), but MoM content increased with presence of aspen [pure aspen (31.2 ± 15.1 Mg C ha-1) > mixed (25.7 ± 8.8 Mg C ha-1) > conifer (22.8 ± 9.0 Mg C ha-1)]. Organo-mineral complexes reduced biological availability of SOC, indicated by the negative correlation between silt+clay (%) and decomposable SOC per gram of C (r = -0.48, p = 0.001) or soluble SOC (r = -0.59, p plant or microbial origin. FTIR spectra clustered by sites with similar parent material rather than by vegetation cover. This suggests that initial differences in litter chemistry between aspen and conifers converged into similar MoM chemistry within sites.

  12. Using High-Resolution Data to Assess Land Use Impact on Nitrate Dynamics in East African Tropical Montane Catchments

    Science.gov (United States)

    Jacobs, Suzanne R.; Weeser, Björn; Guzha, Alphonce C.; Rufino, Mariana C.; Butterbach-Bahl, Klaus; Windhorst, David; Breuer, Lutz

    2018-03-01

    Land use change alters nitrate (NO3-N) dynamics in stream water by changing nitrogen cycling, nutrient inputs, uptake and hydrological flow paths. There is little empirical evidence of these processes for East Africa. We collected a unique 2 year high-resolution data set to assess the effects of land use (i.e., natural forest, smallholder agriculture and commercial tea plantations) on NO3-N dynamics in three subcatchments within a headwater catchment in the Mau Forest Complex, Kenya's largest tropical montane forest. The natural forest subcatchment had the lowest NO3-N concentrations (0.44 ± 0.043 mg N L-1) with no seasonal variation. NO3-N concentrations in the smallholder agriculture (1.09 ± 0.11 mg N L-1) and tea plantation (2.13 ± 0.19 mg N L-1) subcatchments closely followed discharge patterns, indicating mobilization of NO3-N during the rainy seasons. Hysteresis patterns of rainfall events indicate a shift from subsurface flow in the natural forest to surface runoff in agricultural subcatchments. Distinct peaks in NO3-N concentrations were observed during rainfall events after a longer dry period in the forest and tea subcatchments. The high-resolution data set enabled us to identify differences in NO3-N transport of catchments under different land use, such as enhanced NO3-N inputs to the stream during the rainy season and higher annual export in agricultural subcatchments (4.9 ± 0.3 to 12.0 ± 0.8 kg N ha-1 yr-1) than in natural forest (2.6 ± 0.2 kg N ha-1 yr-1). This emphasizes the usefulness of our monitoring approach to improve the understanding of land use effects on riverine N exports in tropical landscapes, but also the need to apply such methods in other regions.

  13. Resilience and stability of Cymodocea nodosa seagrass meadows over the last four decades in a Mediterranean lagoon

    Science.gov (United States)

    Garrido, Marie; Lafabrie, Céline; Torre, Franck; Fernandez, Catherine; Pasqualini, Vanina

    2013-09-01

    Understanding what controls the capacity of a coastal lagoon ecosystem to recover following climatic and anthropogenic perturbations and how these perturbations can alter this capacity is critical to efficient environmental management. The goal of this study was to examine the resilience and stability of Cymodocea nodosa-dominated seagrass meadows in Urbino lagoon (Corsica, Mediterranean Sea) by characterizing the spatio-temporal dynamics of seagrass meadows over a 40-year period and comparing (anthropogenic and climatic) environmental fluctuations. The spatio-temporal evolution of seagrass meadows was investigated using previous maps (1973, 1979, 1990, 1994, 1996, 1999) and a 2011 map realized by aerial photography-remote sensing combined with GIS technology. Environmental fluctuation was investigated via physical-chemical parameters (rainfall, water temperature, salinity, turbidity, dissolved oxygen) and human-impact changes (aquaculture, artificial channel). The results showed a severe decline (estimated at -49%) in seagrass meadows between 1973 and 1994 followed by a period of strong recovery (estimated to +42%) between 1994 and 2011. Increased turbidity, induced either by rainfall events, dredging or phytoplankton growth, emerged as the most important driver of the spatio-temporal evolution of Cymodocea nodosa-dominated meadows in Urbino lagoon over the last four decades. Climate events associated to increased turbidity and reduced salinity and temperature could heavily impact seagrass dynamics. This study shows that Urbino lagoon, a system relatively untouched by human impact, shelters seagrass meadows that exhibit high resilience and stability.

  14. Real-Time Classification of Seagrass Meadows on Flat Bottom with Bathymetric Data Measured by a Narrow Multibeam Sonar System

    Directory of Open Access Journals (Sweden)

    Masahiro Hamana

    2016-01-01

    Full Text Available Seagrass meadows, one of the most important habitats for many marine species, provide essential ecological services. Thus, society must conserve seagrass beds as part of their sustainable development efforts. Conserving these ecosystems requires information on seagrass distribution and relative abundance, and an efficient, accurate monitoring system. Although narrow multibeam sonar systems (NMBSs are highly effective in resolving seagrass beds, post-processing methods are required to extract key data. The purpose of this study was to develop a simple method capable of detecting seagrass meadows and estimating their relative abundance in real time using an NMBS. Because most seagrass meadows grow on sandy seafloors, we proposed a way of discriminating seagrass meadows from the sand bed. We classify meadows into three categories of relative seagrass abundance using the 95% confidence level of beam depths and the depth range of the beam depth. These are respectively two times the standard deviation of beam depths, and the difference between the shallowest and the deepest depths in a 0.5 × 0.5 m grid cell sampled with several narrow beams. We examined Zostera caulescens Miki, but this simple NMBS method of seagrass classification can potentially be used to map seagrass meadows with longer shoots of other species, such as Posidonia, as both have gas filled cavities.

  15. Simulations of dredged sediment spreading on a Posidonia oceanica meadow off the Ligurian coast, Northwestern Mediterranean.

    Science.gov (United States)

    Capello, M; Cutroneo, L; Ferranti, M P; Budillon, G; Bertolotto, R M; Ciappa, A; Cotroneo, Y; Castellano, M; Povero, P; Tucci, S

    2014-02-15

    The sandy deposits from dredging can have negative effects on the environment such as increase in suspended solids in the water column and their consequent transport. An experimental study was conducted to characterize water masses, dynamics, and sedimentation rates on the Ligurian continental shelf (Italy), where both a sand deposit, that could be used for beach nourishment, and a nearby Posidonia oceanica meadow coexist. The environmental plan provides a mathematical simulation of the sediment-dispersion to evaluate the possible impact on the meadow. It has been calculated that the dredging could double the concentration of suspended particles, but its scheduling will preclude a sediment accumulation. All the information obtained from this work will be used to study the environmental feasibility of the sand deposit exploitation and as starting point for drawing up the monitoring plan in case of dredging. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Pedological Studies of Subaqueous Soils as a Contribution to the Protection of Seagrass Meadows in Brazil

    Directory of Open Access Journals (Sweden)

    Gabriel Nuto Nóbrega

    2018-02-01

    Full Text Available ABSTRACT: Seagrass meadows are considered one of the most important and valuable ecosystems on the planet, but also one of the most threatened. Missing knowledge about their existence and their subtidal nature are the main reasons for the lack of information about seagrass soils, especially in Brazil and other tropical areas. This study discussed the paradoxical lack of information about subaqueous soils, with a view to stimulate research on soil properties of seagrass meadows. This short communication provides information about the ecosystem and first descriptions of seagrass soils along the Brazilian Coast, marked by gleyzation, sulfidization, salinization, paludization, solonization, and classified as Gleissolos tiomórficos. Pedological studies on these ecosystems provide useful tools for their management, protection, and restoration. Thus, it is fundamental that soil scientists increase their knowledge about subaqueous soils, not only as a contribution to the Brazilian Soil Classification System, but for the conservation of these ecosystems.

  17. FACTORS AFFECTING GROUND WATER POLLUTION IN THE MEADOW OF BORCEA ARM

    Directory of Open Access Journals (Sweden)

    Cecilia NEAGU

    2014-04-01

    Full Text Available This paper aims to study the factors leading to water pollution by nitrates in the Meadow of Borcea arm, mainly derived from agricultural sources. mIn oder to model the amount of nitrate nitrogen in the soil, which can be partially used by plants or leached into the ground water, research was made on alluvial soil in the Meadow of Borcea arm. I tried to study in the laboratory the influence of three factors of nitrate nitrogen pollution of ground water: soil type, environmental conditions (temperature and humidity and the amount of mineral fertilizers incorporated. The resulting amount of nitrate nitrogen resulted with nitrogen fertilizer dose, and the temperature and it was affected by humidity especially 40-80% of field capacity.

  18. Anaerobic Mono- and Co-digestion of Mechanically Pretreated Meadow Grass for Biogas Production

    DEFF Research Database (Denmark)

    Tsapekos, Panagiotis; Kougias, Panagiotis; Angelidaki, Irini

    2015-01-01

    ), was investigated. The grass silage was mechanically pretreated with different methods to increase its biodegradability. It was found that the early cut of non-treated meadow grass silage led to higher methane production [294 mL of CH4/g of volatile solids (VS)] compared to the corresponding non-treated meadow...... grass silage from the late cut (282 mL of CH4/g of VS). Moreover, it was found that the application of two mesh grating plates, as the pretreatment method, greatly enhanced the methane production in early and late cut silage in a range of 15 and 17%, respectively, compared to the non-treated grass...... ratios in terms of organic matter. The results showed that the optimum silage concentration in the co-digestion mixture with manure, for the highest methane yield, was strongly dependent upon the chemical composition of the manure. More specifically, the ammonia concentration of manure and the C/N ratio...

  19. Natural Radionuclides in Meadow and Pasture land in the Nordic countries

    DEFF Research Database (Denmark)

    Rosén, Klas; Villanueva, José - Luis Gutiérrez; Sundell-Bergman, Synnöve

    transfer for pasture land under the different conditions that prevail in the Nordic countries. The potential health hazards due to chronic ingestion of low concentrations of naturally occurring radionuclides are fairly unknown but the results of this study may provide valuable background information...... for assessing these radiation risks. The aim of this project has been to gain knowledge on the status of natural radionuclides in meadow and pasture land and in grassland plants in different Nordic countries and on the transfer of these radionuclides from soil/water to man via the milk/food chain (soil- meadow/pasture...... grass –cow-milk). Limited data are available on the mobility and the transfer of naturally occurring radionuclides in the ecosystems of the agricultural land. In addition, information concerning the concentrations in meat and dairy products is of interest for assessing exposures of humans to natural...

  20. Stream characteristics and their implications for the protection of riparian fens and meadows

    DEFF Research Database (Denmark)

    Baattrup-Pedersen, A.; Larsen, S.E.; Andersen, Peter Mejlhede

    2011-01-01

    the influence of stream size, morphology and chemical water characteristics for the distribution of water-dependent terrestrial habitat types, i.e. alkaline fens, periodically inundated meadows and meadows in riparian areas in Denmark using an extensive data set covering a total of 254 stream reaches. A species......1. Running waters, including associated riparian areas, are embraced by international legal frameworks outlining targets for the preservation, protection and improvement of the quality of the environment. Interactions between stream and river processes and riparian habitats have not received much...... attention in the management of stream ecosystems, and integrated measures that consider both the ecological status of streams and rivers (sensu EU Water Framework Directive, WFD) and the conservation status of riparian habitats and species (sensu EU Habitats Directive, HD) are rare. 2. Here, we analysed...

  1. Montane and coastal species diversification in the economically important Mexican grasshopper genus Sphenarium (Orthoptera: Pyrgomorphidae).

    Science.gov (United States)

    Pedraza-Lara, Carlos; Barrientos-Lozano, Ludivina; Rocha-Sánchez, Aurora Y; Zaldívar-Riverón, Alejandro

    2015-03-01

    The genus Sphenarium (Pyrgomorphidae) is a small group of grasshoppers endemic to México and Guatemala that are economically and culturally important both as a food source and as agricultural pests. However, its taxonomy has been largely neglected mainly due to its conserved interspecific external morphology and the considerable intraspecific variation in colour pattern of some taxa. Here we examined morphological as well as mitochondrial and nuclear DNA sequence data to assess the species boundaries and evolutionary history in Sphenarium. Our morphological identification and DNA sequence-based species delimitation, carried out with three different approaches (DNA barcoding, general mixed Yule-coalescent model, Bayesian species delimitation), all recovered a higher number of putative species of Sphenarium than previously recognised. We unambiguously delimit seven species, and between five and ten additional species depending on the data/method analysed. Phylogenetic relationships within the genus strongly support two main clades, one exclusively montane, the other coastal. Divergence time estimates suggest late Miocene to Pliocene ages for the origin and most of the early diversification events in the genus, which were probably influenced by the formation of the Trans-Mexican Volcanic Belt. A series of Pleistocene events could have led to the current species diversification in both montane and coastal regions. This study not only reveals an overlooked species richness for the most popular edible insect in Mexico, but also highlights the influence of the dynamic geological and climatic history of the region in shaping its current diversity. Copyright © 2015 Elsevier Inc. All rights reserved.

  2. [Distribution characteristics of heavy metals along an elevation gradient of montane forest].

    Science.gov (United States)

    Wan, Jia-rong; Nie, Ming; Zou, Qin; Hu, Shao-chang; Chen, Jia-kuan

    2011-12-01

    In the present paper, the concentrations of fourteen heavy metals (Fe, Al, Ti, Cu, Cr, Mn, V, Zn, Ni, Co, Pb, Se, Cd and As) were determined by ICP-AES and atomic absorption spectroscopy along an elevation gradient of montane forest. The results show that the elevation gradient had significant effects on the concentrations of Fe, Al, Ti, V, Pb and As. And the concentrations of Cu, Cr, Mn, Zn, Ni, Co, Se and Cd were not significantly affected by the elevation gradient. Because the studying area is red soil, the elevation gradient had significant effects on the concentrations of Fe, Al and Ti which are characteristic heavy metals of red soil, suggesting that the red soil at different elevations has different intensities of weathering desilication and bioaccumulation. Other heavy metals have different relationships with the elevation gradient, such as the concentrations of Cr, Zn and Cd were high at relatively high elevation and Pb and As were high at relatively low elevation. These results suggest that the different elevations of montane forest soils were polluted by differently types of heavy metals.

  3. Phytossociology of wood community in Seasonal Dry Montane Forest in Paraiba, Brazil

    Directory of Open Access Journals (Sweden)

    Maria do Carmo Learth Cunha

    2013-06-01

    Full Text Available The Pico do Jabre Seasonally Dry Montane Forest in Paraiba state, Brazil, the highest regional elevation, 1197 m, distant 360 km the sea was assessed aiming to survey its phytosociology and woody structure. In 36 systematic sampling plots, 10x50m, individuals, Dbh > 4.8cm, had their diameters and height measured. Botanical samples were collected during five years and vouchers were deposited at the Paraiba Federal University Herbaria (JPB. It was found 2050 trees distributed in 64 species of 51 genera of 31 families, which accounted for 1138 ind.ha-1 and 22.45 m2.ha -1. Diversity and equability were assessed as H' = 3.17 nats.ind-1 and J' = 0.76 similar to some others regional seasonally dry montane forest communities. Malpighiaceae, Myrtaceae, Erythroxylaceae, Vochysiaceae, Celastraceae, Rutaceae, Sapindaceae e Fabaceae-Faboideae stood out and summed 66.72% of the total VI. Byrsonima nitidifolia, Eugenia ligustrina, Calisthene microphylla, Maytenus distichophylla and Erythroxylum mucronatum species accounted for 120.79 (40.3% of the total VI. B. nitidifolia ecological dominance is firstly reported in the Brazilian northeast region.

  4. Dataset of Phenology of Mediterranean high-mountain meadows flora (Sierra Nevada, Spain)

    OpenAIRE

    Antonio Jesús Pérez-Luque; Cristina Patricia Sánchez-Rojas; Regino Zamora; Ramón Pérez-Pérez; Francisco Javier Bonet

    2015-01-01

    Abstract Sierra Nevada mountain range (southern Spain) hosts a high number of endemic plant species, being one of the most important biodiversity hotspots in the Mediterranean basin. The high-mountain meadow ecosystems (borreguiles) harbour a large number of endemic and threatened plant species. In this data paper, we describe a dataset of the flora inhabiting this threatened ecosystem in this Mediterranean mountain. The dataset includes occurrence data for flora collected in those ecosystems...

  5. Contents of trace elements in meadow mushrooms as results of PIXE, NAA and AAS measurements

    International Nuclear Information System (INIS)

    Urban, J.; Sieniawski, J.

    1992-01-01

    Contents of heavy elements in mushrooms from the Dresden area and from some parts of Poland, by use of three methods of measurement (PIXE, AAS and NAA) were determined, with the special interest focused on wild growing and cultivated meadow mushrooms. The ability for accumulation of Se, Cu, Ag and Cu was established. In some wild growing mushrooms the values of Cd, Hg, As and Pb exceeded allowed limits for human nutrition. (author). 16 refs, 1 fig., 5 tabs

  6. Expositions of the Botanic Garden of Petrozavodsk State University: "Рagan Meadow"

    OpenAIRE

    Eglacheva Arina

    2015-01-01

    "Pagan Meadow" - one of the business cards of Botanic Garden of PSU filled deep sense of creation and originality. Pyramidal junipers were rescued and brought to the mining sites shungit in 1999. The unique expedition was attended by students and graduate students of the Ecology-Biological Faculty. Stone maze and seids appeared in 2011 as a result of the competition landscape projects "Northern motives." Despite the initial dissociation of the two projects lined up a complete picture of the ...

  7. Patch types in Posidonia oceanica meadows around Corsica. How can we use them in seascape ecology?

    OpenAIRE

    Abadie, Arnaud; Bonacorsi, Marina; Gobert, Sylvie; Lejeune, Pierre; Pergent, Gérard; Pergent-Martini, Christine

    2015-01-01

    The meadows formed by the Mediterranean seagrass Posidonia oceanica are subjected to various natural (e.g., water movement, light availability, sedimentation) and anthropogenic (e.g., anchoring, trawling, fish farms, explosives) phenomena that erode them and create diverse types of patches. The assemblage of the P. oceanica matrix and these patches creates particular seascapes. On the basis of this assessment, we aimed to investigate the importance of the patch type in structuring P. oceanica...

  8. [Soil seed bank in Keerqin meadow grassland under grazing and harvesting].

    Science.gov (United States)

    Jiang, Deming; Li, Rongping; Liu, Zhimin; Yan, Qiaoling

    2004-10-01

    This study on the size and composition of seed bank and its relationship with vegetation showed in Keerqin meadow grassland, the density of soil seed bank was 6158 +/- 1647 grains x m(-2) under grazing and 8312 +/- 2540 grains m(-2) under harvesting. Under grazing, the seed bank was mainly composed of some dwarf and short-life annuals. The seeds of the annuals and biennials accounted for 81.66% of the seeds in seed bank. The four species with largest proportion of seed bank were Chloris virgata, Chenopodium glaucum, Digitaria cilliaris and Setaria viridis, and the proportions were 38.55%, 15.42%, 14.95%, and 9.83%, respectively. The density of perennials in soil seed bank was 1129 +/- 302 grains x m(-2). Under harvesting, the seeds of annuals and biennials accounted for 68.08% of the seed in seed bank, and the proportion of Setaria viridis was 52.7%. In the harvesting meadow grassland, the seed density of perennials was 2653 +/- 811 grains x m(-2). There was no significant correlation between the seed density in soil and the vegetation under grazing, but a significant correlation between the seed density in soil and the species abundance of vegetation under harvesting (r = 0.76, P < 0.01). The index of Shannon-Wiener and richness of grazing meadow grassland were 2.96 and 2.98, respectively, distinctly smaller than 3.10 and 5.09 of harvesting meadow, which showed that free grazing made the diversity of seed bank decrease easily.

  9. Solar radiation and tidal exposure as environmental drivers of Enhalus acoroides dominated seagrass meadows.

    Directory of Open Access Journals (Sweden)

    Richard K F Unsworth

    Full Text Available There is strong evidence of a global long-term decline in seagrass meadows that is widely attributed to anthropogenic activity. Yet in many regions, attributing these changes to actual activities is difficult, as there exists limited understanding of the natural processes that can influence these valuable ecosystem service providers. Being able to separate natural from anthropogenic causes of seagrass change is important for developing strategies that effectively mitigate and manage anthropogenic impacts on seagrass, and promote coastal ecosystems resilient to future environmental change. The present study investigated the influence of environmental and climate related factors on seagrass biomass in a large ≈250 ha meadow in tropical north east Australia. Annual monitoring of the intertidal Enhalus acoroides (L.f. Royle seagrass meadow over eleven years revealed a declining trend in above-ground biomass (54% significant overall reduction from 2000 to 2010. Partial Least Squares Regression found this reduction to be significantly and negatively correlated with tidal exposure, and significantly and negatively correlated with the amount of solar radiation. This study documents how natural long-term tidal variability can influence long-term seagrass dynamics. Exposure to desiccation, high UV, and daytime temperature regimes are discussed as the likely mechanisms for the action of these factors in causing this decline. The results emphasise the importance of understanding and assessing natural environmentally-driven change when interpreting the results of seagrass monitoring programs.

  10. Livestock grazing intensity affects abundance of Common shrews (Sorex araneus) in two meadows in Denmark

    Science.gov (United States)

    Schmidt, Niels M; Olsen, Henrik; Leirs, Herwig

    2009-01-01

    Background Current nature conservation in semi-natural grasslands often includes grazing and hay cutting, as well as the abandonment of draining. Semi-natural grassland and in particular meadows constitute important habitat type for a large number of animal species in today's fragmented and intensively cultivated landscape of Europe. Here we focus on the population characteristics of Common shrews Sorex araneus in relation to livestock grazing intensity in two wet meadows in western Denmark. Results High grazing intensity had a significant negative effect on Common shrew number compared to low grazing intensity and no grazing. Common shrew abundance was generally, but not significantly, higher on the low grazing intensity plots than on the ungrazed controls. No differences in body mass, sex ratio, or reproductive output between Common shrew individuals from the various grazing treatments were found. Conclusion No negative effects of low intensity grazing on Common shrew abundance were found compared to the ungrazed control. Low intensity grazing thus seems a suitable management regime for Common shrews, when grazing is needed as part of the meadow management scheme. High intensity grazing on the other hand is not a suitable management tool. PMID:19152713

  11. Livestock grazing intensity affects abundance of Common shrews (Sorex araneus in two meadows in Denmark

    Directory of Open Access Journals (Sweden)

    Olsen Henrik

    2009-01-01

    Full Text Available Abstract Background Current nature conservation in semi-natural grasslands often includes grazing and hay cutting, as well as the abandonment of draining. Semi-natural grassland and in particular meadows constitute important habitat type for a large number of animal species in today's fragmented and intensively cultivated landscape of Europe. Here we focus on the population characteristics of Common shrews Sorex araneus in relation to livestock grazing intensity in two wet meadows in western Denmark. Results High grazing intensity had a significant negative effect on Common shrew number compared to low grazing intensity and no grazing. Common shrew abundance was generally, but not significantly, higher on the low grazing intensity plots than on the ungrazed controls. No differences in body mass, sex ratio, or reproductive output between Common shrew individuals from the various grazing treatments were found. Conclusion No negative effects of low intensity grazing on Common shrew abundance were found compared to the ungrazed control. Low intensity grazing thus seems a suitable management regime for Common shrews, when grazing is needed as part of the meadow management scheme. High intensity grazing on the other hand is not a suitable management tool.

  12. Conservation state of populations of rare plant species in highly transformed meadow steppes of Southern Opillya

    Directory of Open Access Journals (Sweden)

    I. I. Dmytrash-Vatseba

    2016-09-01

    Full Text Available Degradation of natural habitats causes rapid extinction of rare plant populations. The diversity of rare plant species in the meadow steppes of Southern Opillya (Western Ukraine depends strongly on patch area, pasture digression of vegetation and a variety of eco-coenotical conditions. The main threats for the rare components of the meadow steppe flora are reduction of habitat and overgrazing. Spatial connections between sites are unable to support a constant rare plant population. The analysis of the composition of rare plant meadow-steppe species indicated that habitats with similar rare species composition usually have similar parameters of area, stages of pasture digression and eco-coenotical conditions. Spatial connectivity of patches does not ensure species similarity of rare components of the flora. Rare plant species were grouped according to their preferences for habitat , area and condition. In small patches subject to any stage of pasture digression grow populations of Adonis vernalis L., Pulsatilla patens (L. Mill., P. grandis Wender., Stipa capillata L., S. рennata L., Chamaecytisus blockianus (Pawł. Klásková etc. On the contrary, populations of other species (Carlina onopordifolia Besser. ex Szafer., Kuecz. et Pawł., Adenophora liliifolia (L. Ledeb. ex A. DC., Crambe tataria Sebeók, Euphorbia volhynica Besser ex Racib., Stipa tirsa Stev. etc. prefer large habitats, not changed by pasture digression. Prevention of reduction of rare species diversity requires preservation (also extension of patch area and regulation of grazing intensity.

  13. Long-Term Hydrological Reconstruction From a Beaver Meadow Using Testate Amoebae

    Science.gov (United States)

    Von Ness, K.; Loisel, J.; Karran, D. J.; Westbrook, C.; Kohlmeyer, C.

    2016-12-01

    Beaver ponds contribute up to 0.8 Tg/yr of atmospheric methane (CH4) globally (Whitfield et al., 2014) and were found to be the largest CH4 emitters among all the wetland types in boreal environments (Roulet et al., 1992). However, the sources and underlying mechanisms of carbon emission and sequestration in beaver ponds requires further elucidation. Here we present the historical development of a beaver meadow located in the Sibbald Research Wetland in the Rocky Mountains of Kananaskis Provincial Park, Alberta, Canada. We use a combination of testate amoebae, plant macrofossils, and other geochemical proxies to provide high-resolution reconstructions along three peat cores extracted in hydrologically distinct portions of the meadow. To our knowledge, this is the first attempt at reconstructing long-term hydrological conditions in these systems. Testate amoebae (Protozoa: Rhizopoda) are single-celled organisms that inhabit moist substrates and produce a decay-resistant test. As each taxon generally occupies a discrete ecological niche related to soil moisture and pH, testate amoebae are good indicators of past and ongoing hydrological change. Preliminary analysis of testate amoebae assemblages downcore suggests that this proxy is suitable to reconstruct hydrological changes in meadows, with wetter and drier communities being in good agreement with wetter and drier plant macrofossil assemblages. The nitrogen isotopic signature of peat samples (ongoing) will be used as a proxy for changes in nutrient input; it could become a proxy for past beaver activity.

  14. Long-term changes in structure and composition following hurricanes in a primary lower montane rain forest in Puerto Rico

    Science.gov (United States)

    P.L. Weaver

    2013-01-01

    Ridges within the lower montane rain forests (sensu Beard) of the Caribbean Basin are dominated by Dacryodes excelsa, a tree species known as tabonuco in Puerto Rico and gommier in the Lesser Antilles. Periodially, hurricanes traverse the islands causing changes in structure, species composition, and dynamics of forests. The chronology of post-hurricane vegetation...

  15. Biomass and water storage dynamics of epiphytes in old-growth and secondary montane cloud forest stands in Costa Rica

    NARCIS (Netherlands)

    Koehler, L.; Tobon, C.; Frumau, K.F.A.; Bruijnzeel, L.A.

    2007-01-01

    Epiphytic biomass, canopy humus and associated canopy water storage capacity are known to vary greatly between old-growth tropical montane cloud forests but for regenerating forests such data are virtually absent. The present study was conducted in an old-growth cloud forest and in a 30-year-old

  16. Changes in forest structure and composition after fire in tropical montane cloud forests near the Andean treeline

    NARCIS (Netherlands)

    Oliveras Menor, I.; Malhi, Y.; Salinas, N.; Huaman, V.; Urquiaga-Flores, E.; Kala-Mamani, J.; Quintano-Loaiza, J.A.; Cuba-Torres, I.; Lizarraga-Morales, N.; Roman-Cuesta, R.M.

    2014-01-01

    Background: In tropical montane cloud forests (TMCFs) fires can be a frequent source of disturbance near the treeline. Aims: To identify how forest structure and tree species composition change in response to fire and to identify fire-tolerant species, and determine which traits or characteristics

  17. Long-term fragmentation effects on the distribution and dynamics of canopy gaps in a tropical montane forest

    Science.gov (United States)

    Nicholas R. Vaughn; Gregory P. Asner; Christian P. Giardina

    2015-01-01

    Fragmentation alters forest canopy structure through various mechanisms, which in turn drive subsequent changes to biogeochemical processes and biological diversity. Using repeated airborne LiDAR (Light Detection and Ranging) mappings, we investigated the size distribution and dynamics of forest canopy gaps across a topical montane forest landscape in Hawaii naturally...

  18. Increases in mean annual temperature do not alter soil bacterial community structure in tropical montane wet forests

    Science.gov (United States)

    Paul C. Selmants; Karen L. Adair; Creighton M. Litton; Christian P. Giardina; Egbert Schwartz

    2016-01-01

    Soil bacteria play a key role in regulating terrestrial biogeochemical cycling and greenhouse gas fluxes across the soil-atmosphere continuum. Despite their importance to ecosystem functioning, we lack a general understanding of how bacterial communities respond to climate change, especially in relatively understudied ecosystems like tropical montane wet...

  19. Mammalia, Rodentia, Cricetidae, Neusticomys monticolus (Anthony, 1921): noteworthy records of the Montane Fish- Eating Rat in Colombia

    OpenAIRE

    Velandia-Perilla, Jorge; Saavedra-Rodríguez, Carlos

    2013-01-01

    We document the presence of the Montane Fish-eating Rat, Neusticomys monticolus, in two páramo ecosystems of the Colombian Andes, in the departments of Valle del Cauca and Cauca at 3558 and 3300 m respectively. For small mammals, páramo ecosystems are underexplored zones in a biogeographic context.

  20. Analyzing cloud base at local and regional scales to understand tropical montane cloud forest vulnerability to climate change

    Science.gov (United States)

    Ashley E. Van Beusekom; Grizelle Gonzalez; Martha A. Scholl

    2017-01-01

    The degree to which cloud immersion provides water in addition to rainfall, suppresses transpiration, and sustains tropical montane cloud forests (TMCFs) during rainless periods is not well understood. Climate and land use changes represent a threat to these forests if cloud base altitude rises as a result of regional warming or deforestation. To establish a baseline...

  1. Culvert flow in small drainages in montane tropical forests: observations from the Luquillo Experimental Forest of Puerto Rico.

    Science.gov (United States)

    F. N. Scatena

    1990-01-01

    This paper describe the hydraulics of unsubmerged flow for 5 culverts in the Luiquillo Esperimental Forest of Puerto Rico. A General equation based on empirical data is presented to estimate culvert discharge during unsubmerged conditions. Large culverts are needed in humid tropical montane areas than in humid temperatute watersheds and are usually appropriate only...

  2. Dawn chorus variation in East-Asian tropical montane forest birds and its ecological and morphological correlates

    NARCIS (Netherlands)

    Chen, W.-M.; Lee, Y.-F.; Tsai, C.-F.; Yao, C.-T.; Chen, Y.-H.; Li, S.-H.; Kuo, Y.-M.

    2015-01-01

    Many birds in breeding seasons engage in vigorous dawn singing that often turns to a prominent chorus. We examined dawn chorus variation of avian assemblages in a tropical montane forest in Taiwan and tested the hypothesis that onset sequence is affected by eye sizes, foraging heights, and diet of

  3. Vegetation changes along gradients of long-term soil development in the Hawaiian montane rainforest zone11-219.

    Science.gov (United States)

    Kanehiro Kitayama; Dieter Mueller-Dombois

    1995-01-01

    The development of the Hawaiian montane rainforest was investigated along a 4.1-million-year soil age gradient at 1200 m elevation under two levels of precipitation, the mesic (c. 2500 mm annual rainfall) vs. wet (> 4000 mm)age gradient. Earlier analyses suggested that soil fertility and foliar nutrient concentrations of common canopy species changed unimodally on...

  4. Diversity and distribution patterns of root-associated fungi on herbaceous plants in alpine meadows of southwestern China.

    Science.gov (United States)

    Gao, Qian; Yang, Zhu L

    2016-01-01

    The diversity of root-associated fungi associated with four ectomycorrhizal herbaceous species, Kobresia capillifolia, Carex parva, Polygonum macrophyllum and Potentilla fallens, collected in three sites of alpine meadows in southwestern China, was estimated based on internal transcribed spacer (ITS) rDNA sequence analysis of root tips. Three hundred seventy-seven fungal sequences sorted to 154 operational taxonomical units (sequence similarity of ≥ 97% across the ITS) were obtained from the four plant species across all three sites. Similar taxa (in GenBank with ≥ 97% similarity) were not found in GenBank and/or UNITE for most of the OTUs. Ectomycorrhiz a made up 64% of the fungi operational taxonomic units (OTUs), endophytes constituted 4% and the other 33% were unidentified root-associated fungi. Fungal OTUs were represented by 57% basidiomycetes and 43% ascomycetes. Inocybe, Tomentella/Thelophora, Sebacina, Hebeloma, Pezizomycotina, Cenococcum geophilum complex, Cortinarius, Lactarius and Helotiales were OTU-rich fungal lineages. Across the sites and host species the root-associated fungal communities generally exhibited low host and site specificity but high host and sampling site preference. Collectively our study revealed noteworthy diversity and endemism of root-associated fungi of alpine plants in this global biodiversity hotspot. © 2016 by The Mycological Society of America.

  5. Performance of four Dactylorhiza species over a complex trophic gradient

    NARCIS (Netherlands)

    Dijk, E; Grootjans, AB

    Spontananeous distribution and survival in experimental plots of four marsh orchids (Dactylorhiza spp.) in a hay-meadow complex were related to mineral composition of groundwater, soil nutrient availability and species composition of the vegetation. Differences in Ca2+ contents of the groundwater

  6. Utilization of old meadow by reindeer in spring in northern Norway

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    Svein M. Eilertsen

    1999-04-01

    Full Text Available Utilization of abandoned coastal meadows in northern Norway by reindeer (Rangifer tarandus tarandus were investigated for 25 days in spring 1996 (« = 12, 40-57 kg body mass (BM and 24 days in 1997 (» = 12, 39-61 kg BM. Grass production on grazed and ungrazed meadow was measured both years. Faecal dry matter (DM production and ruminai in vitro DM digestibility (IVDMD of selected plants were measured in the reindeer 15-22 days after the grazing experiment started each year. During the grazing period mean, standard deviation (s, temperature was 8.7, s = 2.8, °C in 1996 and 11.0, s = 3.0, °C in 1997, while temperature the first week was significantly higher in 1997 (P < 0.05. Mean herbage mass, on ungrazed meadow (control, after one week of plant growth in 1996 (408, J" = 166, kg DM ha"1 was significantly different (P < 0.05 from 1997 (576, s = 110, kg DM ha'. We believe the low temperature the first week in 1996 affected the plant production, and was the main reason for the significant (P < 0.05 difference in mean daily plant DM production on the grazed meadow between 1996 (57, s = 16, kg DM ha' and 1997 (81, s = 16, kg DM ha"1. Mean ruminai IVDMD of a mixture of meadow plants, differed (P<0.05 between 1996 (72.4, s = 1.0, % and 1997 (83.9, s = 1.3, %, and mean daily food intake in 1996 (82, s = 13.5, g DM/kg0 75 was significantly lower than the intake in 1997 (131, s = 15.8, g DM/kg0 75. Daily digestible energy intake in reindeer was estimated to 0.96 Ml/kg07"5 X d 1 in 1996 and 1.85 Ml/kg""5 X d"1 in 1997, which was 1.3 and 2.5 times the resting metabolic rate in reindeer, respectively. We therefore assume the difference in food intake could be due to the initial difference in herbage mass.

  7. Estimation of canopy water interception of a near-tropical montane cloud forest in Taiwan

    Science.gov (United States)

    Apurva, B.; Huang, C. Y.; Zhang, J.

    2017-12-01

    Tropical and subtropical montane cloud forests are some of the rarest and least studied ecosystems. Due to the frequent immersion of fog water with high humidity, these zones are major water sources for lowland environments and habitats for many fauna and flora. Their dependence on cloud water leaves them highly susceptible to the effects of climate change. Studies have been conducted to quantify the characteristics of the low altitude clouds such as spatial dynamics, cloud top and base heights, occurrence frequency or immersion duration. In this study, we carried out a field measurement to estimate canopy water interception (CWI), which is directly utilized by the ecosystems. The study site was a 61 ha near-tropical hinoki cypress montane cloud forest plantation in northern Taiwan at 1705 m asl. Leaves of CHOB were clipped, air-dried and attached to trees at three different canopy depths from the top to the base of canopies along a high tower. The samples were weighed before and after the occurrence of a fog event. In addition, a cylinder shaped fog gauge was installed at the ground level next to the tower to assess amount of fog water penetrating the canopy layer. After afternoon fog events with the duration of 60 minutes, we found that there was an apparent trend of decline of CWI from top (mean ± standard deviation = 0.023 g ± 0.0015 g), middle (0.021 g ± 0.0015 g) to the bottom (0.013 g ± 0.0015 g) of the canopies. Since the study site is a coniferous evergreen forest plantation with a relatively homogenous surface through seasons, with the background knowledge of the average leaf area index of 4.4, we estimated that this 61 ha site harvested 28.2 Mg of CWI for a daily fog event. We also found that no clear evidence of CWI was observed below the canopies by referring to bi-weekly records from the cylinder shaded fog gauge. Therefore, we can assume that the majority fog water was intercepted by the hinoki cypress canopy layer. This study demonstrates that a

  8. Carbon budget of Nyungwe Tropical Montane Rain Forest in Central Africa

    Science.gov (United States)

    Nyirambangutse, B.; Zibera, E.; Uwizeye, F. K.; Hansson, L.; Nsabimana, D.; Pleijel, H.; Uddling, J.; Wallin, G.

    2015-12-01

    African tropical rainforests host rich biodiversity and play many roles at different scales such as local, regional and global, in the functioning of the earth system. Despite that the African tropical forests are the world's second largest, it has been neglected in terms of understanding the storage and fluxes of carbon and other nutrients. The question of whether this biome is a net sink or source of atmospheric CO2 is still not answered, and little is known concerning the climate change response. Tropical montane forests are even more poorly sampled compared with their importance. Deeper understanding of these ecosystems is required to provide insights on how they might react under global change. To answer questions related to these issues for African tropical montane forests, 15 permanent 0.5 ha plots were established in 2011 in Nyungwe tropical montane rainforest gazetted as a National Park to protect its extensive floral and faunal diversity. The plots are arranged along an east-westerly transect and includes both primary and secondary forest communities. The study is connected to the global ecosystem monitoring network (GEM, http://gem.tropicalforests.ox.ac.uk/). The aim is to characterize spatial and temporal heterogeneity of carbon and nutrient dynamics processes. The role of microclimate, topography, human disturbances, and plant species to the variability of these pools and processes will be explored. We compare stocks and fluxes of carbon and nutrients of the secondary and primary forest communities. The carbon stock are determined by an inventory of height and diameter at breast height (dbh) of all trees with a dbh above 5 cm, wood density, biomass of understory vegetation, leaf area index, standing and fallen dead wood, fine root biomass and organic content of various soil layers (litter, organic and mineral soil down to 45 cm depth). The carbon fluxes are determined by measurements of photosynthesis and respiration of leaves, above and below ground

  9. Experimental Warming Aggravates Degradation-Induced Topsoil Drought in Alpine Meadows of The Qinghai-Tibetan Plateau

    Science.gov (United States)

    Xue, X.

    2017-12-01

    Climatic warming is presumed to cause topsoil drought by increasing evapotranspiration and water infiltration, and by progressively inducing land degradation in alpine meadows of the Qinghai-Tibetan Plateau. However, how soil moisture and temperature patterns of degraded alpine meadows respond to climate warming remains unclear. A six-year continuous warming experiment was carried out in both degraded and undegraded alpine meadows in the source region of the Yangtze River. The goal was to identify the effects of climatic warming and land degradation on soil moisture (θ), soil surface temperature (Tsfc), and soil temperature (Ts). In the present study, land degradation significantly reduced θ by 4.5-6.1% at a depth of 0-100 cm (P soil surface. Experimental warming aggravated topsoil drought caused by land degradation, intensified the magnitude of degradation, and caused a positive feedback in the degraded alpine meadow ecosystem. Therefore, an immediate need exists to restore degraded alpine meadow grasslands in the Qinghai-Tibetan Plateau in anticipation of a warmer future.

  10. Agaricomycetes in low land and montane Atlantic Rain Forest in Northeast Brazil

    Directory of Open Access Journals (Sweden)

    Tatiana Gibertoni

    2014-10-01

    Full Text Available The Atlantic Rain Forest represents a group of extra-amazonic forests, among which the coastal and montane (“brejos de altitude” are the most common in Northeast Brazil. Between 2011 and 2013, 110 field trips were performed in nine reserves in the domain of the Atlantic Rain Forest. Two thousand two hundred sixty three Agaricomycetes were collected and represented 271 species, among which several new species to science, new occurrences to the continent, country, region, biome and States were found. Besides recently collected material, 309 exsiccates of Agaricomycetes deposited in the Herbarium URM were revised and represented 38 species, among which several new occurrences to the region and States. The results indicate the importance of the constant inventories and also of revisions of material deposited in herbaria as tools to improve the knowledge about the Brazilian micota.

  11. Species composition of the vegetation along the Sherichhu River, lower montane area of Eastern Bhutan

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    Tenzin Jamtsho

    2017-06-01

    Full Text Available An investigation of the riparian vegetation along the Sherichhu River, lower montane area of Eastern Bhutan was conducted from April to December 2015 to explore the plant communities in terms of species composition. A total number of 18 plots were placed within the remnant patches of the vegetation on either side of the river. In total, 172 species of vascular plant has been recorded. The cluster analysis suggested four types of plant communities in the study area viz., the MallotusDesmodium-Rhus shrubland and the Syzygium venosum woodland communities, which are located in V-shaped valleys and the Albizia-Flueggea woodland and Quercus glauca woodland communities located in U-shaped valleys. In broad-spectrum, the topographic features and environmental variables i.e. litter accumulation and flooding condition might also have some impact on the species composition of the plant communities of this vegetation.

  12. Evidence of a high density population of harvested leopards in a montane environment.

    Science.gov (United States)

    Chase Grey, Julia N; Kent, Vivien T; Hill, Russell A

    2013-01-01

    Populations of large carnivores can persist in mountainous environments following extensive land use change and the conversion of suitable habitat for agriculture and human habitation in lower lying areas of their range. The significance of these populations is poorly understood, however, and little attention has focussed on why certain mountainous areas can hold high densities of large carnivores and what the conservation implications of such populations might be. Here we use the leopard (Panthera pardus) population in the western Soutpansberg Mountains, South Africa, as a model system and show that montane habitats can support high numbers of leopards. Spatially explicit capture-recapture (SECR) analysis recorded the highest density of leopards reported outside of state-protected areas in sub-Saharan Africa. This density represents a temporally high local abundance of leopards and we explore the explanations for this alongside some of the potential conservation implications.

  13. Evidence of a high density population of harvested leopards in a montane environment.

    Directory of Open Access Journals (Sweden)

    Julia N Chase Grey

    Full Text Available Populations of large carnivores can persist in mountainous environments following extensive land use change and the conversion of suitable habitat for agriculture and human habitation in lower lying areas of their range. The significance of these populations is poorly understood, however, and little attention has focussed on why certain mountainous areas can hold high densities of large carnivores and what the conservation implications of such populations might be. Here we use the leopard (Panthera pardus population in the western Soutpansberg Mountains, South Africa, as a model system and show that montane habitats can support high numbers of leopards. Spatially explicit capture-recapture (SECR analysis recorded the highest density of leopards reported outside of state-protected areas in sub-Saharan Africa. This density represents a temporally high local abundance of leopards and we explore the explanations for this alongside some of the potential conservation implications.

  14. Surface runoff fluxes of nutrients in montane forests in Piedras Blancas region, Antioquia (Colombia)

    International Nuclear Information System (INIS)

    Ruiz Suescun, Oscar Andres; Acosta Jaramillo, Juan Jose; Leon Pelaez, Juan Diego

    2005-01-01

    In natural montane oak forests (Quercus humboldtii Bonpl.), pine (Pinus patula Schltdl and cham.) and cypress (Cupressus lusitanica Mill.) plantations in the region of Piedras Blancas, Antioquia, surface runoff flows (SRF) were measured over 16 months. Runoff was measured using 2 m wide x 10 m long runoff bounded plots, collector tanks and a volumetric counter system. Nutrient flows for the oak forest, pine and cypress plantations were, respectively: P total (0,51, 0,08 and 0,42 kg ha-y), Ca (0,13, 0,21 and 1,27 kg ha- y); Mg (0,07, 0,07 and 0,34 kg ha-y); K (0,89, 0,71 and 2,60 kg ha-y); Fe (0,04, 0,04 and 0,47 kg ha-y) and Mn (0,01, 0,01 and 0,08 kg ha-y)

  15. Balligratus, new genus of wingless ground beetles from equatorial Andean montane forest (Coleoptera: Carabidae: Lachnophorini).

    Science.gov (United States)

    Moret, Pierre; Ortuño, Vicente M

    2017-04-27

    A new carabid beetle genus, Balligratus gen. nov., belonging to the tribe Lachnophorini, is described. It is geographically restricted to the equatorial Andes, and ecologically linked to the montane pluvial forest ecosystem, at elevations ranging from 1,200 to 3,600 m. As other carabid lineages that have radiated in such environments, Balligratus gen. nov. is a wingless clade, characterized by the loss of flight wings associated with metathoracic reduction, constriction of the elytral base, and reduced eye size. This evolution is unique among Lachnophorini. Four new species are described, all of them from Ecuador: Balligratus brevis sp. nov., Balligratus globosus sp. nov., Balligratus gracilis sp. nov. and Balligratus humerangulus sp. nov.

  16. Atmospheric mercury inputs in montane soils increase with elevation: evidence from mercury isotope signatures.

    Science.gov (United States)

    Zhang, Hua; Yin, Run-sheng; Feng, Xin-bin; Sommar, Jonas; Anderson, Christopher W N; Sapkota, Atindra; Fu, Xue-wu; Larssen, Thorjørn

    2013-11-25

    The influence of topography on the biogeochemical cycle of mercury (Hg) has received relatively little attention. Here, we report the measurement of Hg species and their corresponding isotope composition in soil sampled along an elevational gradient transect on Mt. Leigong in subtropical southwestern China. The data are used to explain orography-related effects on the fate and behaviour of Hg species in montane environments. The total- and methyl-Hg concentrations in topsoil samples show a positive correlation with elevation. However, a negative elevation dependence was observed in the mass-dependent fractionation (MDF) and mass-independent fractionation (MIF) signatures of Hg isotopes. Both a MIF (Δ(199)Hg) binary mixing approach and the traditional inert element method indicate that the content of Hg derived from the atmosphere distinctly increases with altitude.

  17. Instream wood loads in montane forest streams of the Colorado Front Range, USA

    Science.gov (United States)

    Jackson, Karen J.; Wohl, Ellen

    2015-04-01

    Although several studies examine instream wood loads and associated geomorphic effects in streams of subalpine forests in the U.S. Southern Rocky Mountains, little is known of instream wood loads in lower elevation, montane forests of the region. We compare instream wood loads and geomorphic effects between streams draining montane forest stands of differing age (old growth versus younger) and disturbance history (healthy versus infested by mountain pine beetles). We examined forest stand characteristics, instream wood load, channel geometry, pool volume, and sediment storage in 33 pool-riffle or plane-bed stream reaches with objectives of determining whether (i) instream wood and geomorphic effects differed significantly among old-growth, younger, healthy, and beetle-infested forest stands and (ii) wood loads correlated with valley and channel characteristics. Wood loads were standardized to drainage area, stream gradient, reach length, bankfull width, and floodplain area. Streams flowing through old-growth forests had significantly larger wood loads and logjam volumes (pairwise t-tests), as well as logjam frequencies (Kruskal-Wallis test), residual pool volume, and fine sediment storage around wood than streams flowing through younger forests. Wood loads in streams draining beetle-infested forest did not differ significantly from those in healthy forest stands, but best subset regression models indicated that elevation, stand age, and beetle infestation were the best predictors of wood loads in channels and on floodplains, suggesting that beetle infestation is affecting instream wood characteristics. Wood loads are larger than values from subalpine streams in the same region and jams are larger and more closely spaced. We interpret these differences to reflect greater wood piece mobility in subalpine zone streams. Stand age appears to exert the dominant influence on instream wood characteristics within pool-riffle streams in the study area rather than beetle

  18. Elevational Ranges of Montane Birds and Deforestation in the Western Andes of Colombia.

    Directory of Open Access Journals (Sweden)

    Natalia Ocampo-Peñuela

    Full Text Available Deforestation causes habitat loss, fragmentation, degradation, and can ultimately cause extinction of the remnant species. Tropical montane birds face these threats with the added natural vulnerability of narrower elevational ranges and higher specialization than lowland species. Recent studies assess the impact of present and future global climate change on species' ranges, but only a few of these evaluate the potentially confounding effect of lowland deforestation on species elevational distributions. In the Western Andes of Colombia, an important biodiversity hotspot, we evaluated the effects of deforestation on the elevational ranges of montane birds along altitudinal transects. Using point counts and mist-nets, we surveyed six altitudinal transects spanning 2200 to 2800 m. Three transects were forested from 2200 to 2800 m, and three were partially deforested with forest cover only above 2400 m. We compared abundance-weighted mean elevation, minimum elevation, and elevational range width. In addition to analysing the effect of deforestation on 134 species, we tested its impact within trophic guilds and habitat preference groups. Abundance-weighted mean and minimum elevations were not significantly different between forested and partially deforested transects. Range width was marginally different: as expected, ranges were larger in forested transects. Species in different trophic guilds and habitat preference categories showed different trends. These results suggest that deforestation may affect species' elevational ranges, even within the forest that remains. Climate change will likely exacerbate harmful impacts of deforestation on species' elevational distributions. Future conservation strategies need to account for this by protecting connected forest tracts across a wide range of elevations.

  19. Elevational Ranges of Montane Birds and Deforestation in the Western Andes of Colombia.

    Science.gov (United States)

    Ocampo-Peñuela, Natalia; Pimm, Stuart L

    2015-01-01

    Deforestation causes habitat loss, fragmentation, degradation, and can ultimately cause extinction of the remnant species. Tropical montane birds face these threats with the added natural vulnerability of narrower elevational ranges and higher specialization than lowland species. Recent studies assess the impact of present and future global climate change on species' ranges, but only a few of these evaluate the potentially confounding effect of lowland deforestation on species elevational distributions. In the Western Andes of Colombia, an important biodiversity hotspot, we evaluated the effects of deforestation on the elevational ranges of montane birds along altitudinal transects. Using point counts and mist-nets, we surveyed six altitudinal transects spanning 2200 to 2800 m. Three transects were forested from 2200 to 2800 m, and three were partially deforested with forest cover only above 2400 m. We compared abundance-weighted mean elevation, minimum elevation, and elevational range width. In addition to analysing the effect of deforestation on 134 species, we tested its impact within trophic guilds and habitat preference groups. Abundance-weighted mean and minimum elevations were not significantly different between forested and partially deforested transects. Range width was marginally different: as expected, ranges were larger in forested transects. Species in different trophic guilds and habitat preference categories showed different trends. These results suggest that deforestation may affect species' elevational ranges, even within the forest that remains. Climate change will likely exacerbate harmful impacts of deforestation on species' elevational distributions. Future conservation strategies need to account for this by protecting connected forest tracts across a wide range of elevations.

  20. Inventory of montane-nesting birds in Katmai and Lake Clark national parks and preserves

    Science.gov (United States)

    Ruthrauff, Daniel R.; Tibbitts, Lee; Gill, Robert E.; Handel, Colleen M.

    2007-01-01

    As part of the National Park Service’s Inventory and Monitoring Program, biologists from the U. S. Geological Survey’s Alaska Science Center conducted an inventory of birds in montane regions of Katmai and Lake Clark National Parks and Preserves during 2004–2006. We used a stratified random survey design to allocate samples by ecological subsection. To survey for birds, we conducted counts at 468 points across 29, 10-km x 10-km (6.2-mi x 6.2-mi) sample plots in Katmai and 417 points across 25, 10-km x 10-km sample plots in Lake Clark. We detected 92 and 104 species in Katmai and Lake Clark, respectively, including 40 species of conservation concern. We detected three species not previously recorded in Katmai (Ring-necked Duck [Aythya collaris], Lesser Scaup [Aythya affinis], and White-tailed Ptarmigan [Lagopus leucurus]) and two species not previously recorded in Lake Clark (Northern Flicker [Colaptes auratus ] and Olive-sided Flycatcher [Contopus cooperi]). The most commonly detected species in both parks was Golden-crowned Sparrow (Zonotrichia atricapilla); Fox Sparrow (Passerella iliaca) and American Pipit (Anthus rubescens) were abundant and widely-distributed as well. We defined sites as low (100–350 m), middle (351–600 m), or high (601–1,620 m) elevation based on the distribution of vegetation cover, and similarly categorized the 34 most-commonly detected species based on the mean elevation of sample points at which they were detected. High elevation (i.e., alpine) sites were characterized by high percent cover of dwarf shrub and bare ground habitat and supported species like Rock Ptarmigan (L. mutus), American Golden-Plover (Pluvialis dominica), Wandering Tattler (Tringa incana), Surfbird (Aphriza virgata), and Snow Bunting (Plectrophenax nivalis), all species of conservation concern. This inventory represents the first systematic survey of birds nesting in montane regions of both parks. Results from this inventory can form the foundation of

  1. Information to support to monitoring and habitat restoration on Ash Meadows National Wildlife Refuge

    Science.gov (United States)

    Scoppettone, G. Gary

    2013-01-01

    The Ash Meadows National Wildlife Refuge staff focuses on improving habitat for the highest incidence of endemic species for an area of its size in the continental United States. Attempts are being made to restore habitat to some semblance of its pre-anthropogenic undisturbed condition, and to provide habitat conditions to which native plant and animal species have evolved. Unfortunately, restoring the Ash Meadows’ Oases to its pre-anthropogenic undisturbed condition is almost impossible. First, there are constraints on water manipulation because there are private holdings within the refuge boundary; second, there has been at least one species extinction—the Ash Meadows pool fish (Empetrichthys merriami). It is also quite possible that thermal endemic invertebrate species were lost before ever being described. Perhaps the primary obstacle to restoring Ash Meadows to its pre-anthropogenic undisturbed conditions is the presence of invasive species. However, invasive species, such as red swamp crayfish (Procambarus clarki) and western mosquitofish (Gambusia affinis), are a primary driving force in restoring Ash Meadows’ spring systems, because under certain habitat conditions they can all but replace native species. Returning Ash Meadows’ physical landscape to some semblance of its pre-anthropogenic undisturbed condition through natural processes may take decades. Meanwhile, the natural dissolution of concrete and earthen irrigation channels threatens to allow cattail marshes to flourish instead of spring-brooks immediately downstream of spring discharge. This successional stage favors non-native crayfish and mosquitofish over the native Amargosa pupfish (Cyprinodon nevadensis). Thus, restoration is needed to control non-natives and to promote native species, and without such intervention the probability of native fish reduction or loss, is anticipated. The four studies in this report are intended to provide information for restoring native fish habitat and

  2. Soil Fauna Affects Dissolved Carbon and Nitrogen in Foliar Litter in Alpine Forest and Alpine Meadow.

    Science.gov (United States)

    Liao, Shu; Yang, Wanqin; Tan, Yu; Peng, Yan; Li, Jun; Tan, Bo; Wu, Fuzhong

    2015-01-01

    Dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) are generally considered important active biogeochemical pools of total carbon and nitrogen. Many studies have documented the contributions of soil fauna to litter decomposition, but the effects of the soil fauna on labile substances (i.e., DOC and TDN) in litter during early decomposition are not completely clear. Therefore, a field litterbag experiment was carried out from 13th November 2013 to 23rd October 2014 in an alpine forest and an alpine meadow located on the eastern Tibetan Plateau. Litterbags with different mesh sizes were used to provide access to or prohibit the access of the soil fauna, and the concentrations of DOC and TDN in the foliar litter were measured during the winter (the onset of freezing, deep freezing and thawing stage) and the growing season (early and late). After one year of field incubation, the concentration of DOC in the litter significantly decreased, whereas the TDN concentration in the litter increased. Similar dynamic patterns were detected under the effects of the soil fauna on both DOC and TDN in the litter between the alpine forest and the alpine meadow. The soil fauna showed greater positive effects on decreasing DOC concentration in the litter in the winter than in the growing season. In contrast, the dynamics of TND in the litter were related to seasonal changes in environmental factors, rather than the soil fauna. In addition, the soil fauna promoted a decrease in litter DOC/TDN ratio in both the alpine forest and the alpine meadow throughout the first year of decomposition, except for in the late growing season. These results suggest that the soil fauna can promote decreases in DOC and TDN concentrations in litter, contributing to early litter decomposition in these cold biomes.

  3. Tropical seagrass meadows modify seawater carbon chemistry: implications for coral reefs impacted by ocean acidification

    International Nuclear Information System (INIS)

    Unsworth, Richard K F; Collier, Catherine J; Henderson, Gideon M; McKenzie, Len J

    2012-01-01

    Highly productive tropical seagrasses often live adjacent to or among coral reefs and utilize large amounts of inorganic carbon. In this study, the effect of seagrass productivity on seawater carbonate chemistry and coral calcification was modelled on the basis of an analysis of published data. Published data (11 studies, 64 records) reveal that seagrass meadows in the Indo-Pacific have an 83% chance of being net autotrophic, resulting in an average net sink of 155 gC m −2 yr −1 . The capacities for seagrass productivity were analysed using an empirical model to examine the effect on seawater carbonate chemistry. Our analyses indicate that increases in pH of up to 0.38 units, and Ω arag increases of 2.9 are possible in the presence of seagrass meadows (compared to their absence) with the precise values of these increases dependent on water residence time (tidal flushing) and water depth. In shallow water reef environments, Scleractinian coral calcification downstream of seagrass has the potential to be ≈18% greater than in an environment without seagrass. If this potential benefit to reef calcifiers is supported by further study it offers a potential tool in marine park management at a local scale. The applicability of this will depend upon local physical conditions as well as the spatial configuration of habitats, and the factors that influence their productivity. This novel study suggests that, in addition to their importance to fisheries, sediment stabilization and primary production, seagrass meadows may enhance coral reef resilience to future ocean acidification. (letter)

  4. The responses to supplementary of UV radiation of some temperate meadow species

    International Nuclear Information System (INIS)

    Cooley, N.M.

    2002-01-01

    Full text: The growth and development of various meadow species was monitored while growing under enhanced UV-radiation in the natural light environment. Growth responses to supplementary ultraviolet-B (UV-B+A) and ultraviolet-A (UV-A) were compared to the ambient daylight treatment for Bellis perennis, Cardamine pratensis, Cynosurus critatus and Ranunculus ficaria. When the response of ultraviolet A (UV-A) treated plants were compared with those of the UV-B+A, differences were found which varied according to the species and parameter investigated. To further understand the growth responses of the UV-A treatment and their relationship to the UV-B responses polychromatic action spectra in the natural environment was employed B perennis had an action maximum in the UV B (280-315 nm) while C cristatus demonstrates no action in the UV-B but action in the UV-A region (315-400 nm.). To enable further explanation of the effects of elevated UV radiation on the meadow plants Arabidopsis thaliana ecotypes and mutants were investigated. A thaliana ecotypes dry weight accumulation was found to respond differently to the UV treatments. UV B+A treatment was found to inhibit dry weight accumulation in most ecotypes. When UV B+A induced inhibition was expressed in terms of ambient growth rate for each ecotype a linear relationship could be derived. The higher the growth rate the more susceptible the ecotype was to UV-B+A inhibition. The pertinence of the UV-A treatment and UV protocol is discussed. It is suggested that UV responses could alter the diversity of the meadow equilibrium

  5. A modified MOD16 algorithm to estimate evapotranspiration over alpine meadow on the Tibetan Plateau, China

    Science.gov (United States)

    Chang, Yaping; Qin, Dahe; Ding, Yongjian; Zhao, Qiudong; Zhang, Shiqiang

    2018-06-01

    The long-term change of evapotranspiration (ET) is crucial for managing water resources in areas with extreme climates, such as the Tibetan Plateau (TP). This study proposed a modified algorithm for estimating ET based on the MOD16 algorithm on a global scale over alpine meadow on the TP in China. Wind speed and vegetation height were integrated to estimate aerodynamic resistance, while the temperature and moisture constraints for stomatal conductance were revised based on the technique proposed by Fisher et al. (2008). Moreover, Fisher's method for soil evaporation was adopted to reduce the uncertainty in soil evaporation estimation. Five representative alpine meadow sites on the TP were selected to investigate the performance of the modified algorithm. Comparisons were made between the ET observed using the Eddy Covariance (EC) and estimated using both the original and modified algorithms. The results revealed that the modified algorithm performed better than the original MOD16 algorithm with the coefficient of determination (R2) increasing from 0.26 to 0.68, and root mean square error (RMSE) decreasing from 1.56 to 0.78 mm d-1. The modified algorithm performed slightly better with a higher R2 (0.70) and lower RMSE (0.61 mm d-1) for after-precipitation days than for non-precipitation days at Suli site. Contrarily, better results were obtained for non-precipitation days than for after-precipitation days at Arou, Tanggula, and Hulugou sites, indicating that the modified algorithm may be more suitable for estimating ET for non-precipitation days with higher accuracy than for after-precipitation days, which had large observation errors. The comparisons between the modified algorithm and two mainstream methods suggested that the modified algorithm could produce high accuracy ET over the alpine meadow sites on the TP.

  6. X-Ray fluorescence determination of the mobile forms of toxic elements in meadow chernozems

    International Nuclear Information System (INIS)

    Belikov, K.N.; Blank, A.B.; Shevtsov, N.I.

    1997-01-01

    An X-ray fluorescence method for determining mobile forms of Mn, V, Cr, Co, Ni, Zn, and Pb in meadow chernozems was developed. It is based on the extraction of analytes with an acetate-ammonia buffer solution and the evaporation of the obtained filtrate with carbon powder followed by the X-ray fluorescence analysis of the dry residue. The effect of concomitants on the analytical signals of elements under determination was examined. It was suggested to spike samples with barium in order to decrease analytical errors. (author)

  7. Diversification of mowing regime increases arthropods diversity in species-poor cultural hay meadows

    Czech Academy of Sciences Publication Activity Database

    Čížek, O.; Zámečník, J.; Tropek, Robert; Kočárek, P.; Konvička, Martin

    2012-01-01

    Roč. 16, č. 2 (2012), s. 215-226 ISSN 1366-638X R&D Projects: GA MŠk LC06073; GA ČR GD206/08/H044; GA MŽP SP/2D3/62/08 Grant - others:Czech Agency for Nature Conservation(CZ) PPK-35a/62/06 Institutional research plan: CEZ:AV0Z50070508 Keywords : hay meadows * arthropods conservation * mowing regimes Subject RIV: EH - Ecology, Behaviour Impact factor: 1.801, year: 2012 http://www.muzeumhk.cz/files/jaroslav_zamecnik/2012_cizek_zamecnik.pdf

  8. Long-Term Vegetation Dynamics in a Megadiverse Hotspot: The Ice-Age Record of a Pre-montane Forest of Central Ecuador

    Directory of Open Access Journals (Sweden)

    Encarni Montoya

    2018-02-01

    Full Text Available Tropical ecosystems play a key role in many aspects of Earth system dynamics currently of global concern, including carbon sequestration and biodiversity. To accurately understand complex tropical systems it is necessary to parameterise key ecological aspects, such as rates of change (RoC, species turnover, dynamism, resilience, or stability. To obtain a long-term (>50 years perspective on these ecological aspects we must turn to the fossil record. However, compared to temperate zones, collecting continuous sedimentary archives in the lowland tropics is often difficult due to the active landscape processes, with potentially frequent volcanic, tectonic, and/or fluvial events confounding sediment deposition, preservation, and recovery. Consequently, the nature, and drivers, of vegetation dynamics during the last glacial are barely known from many non-montane tropical landscapes. One of the first lowland Amazonian locations from which palaeoecological data were obtained was an outcrop near Mera (Ecuador. Mera was discovered, and analysed, by Paul Colinvaux in the 1980s, but his interpretation of the data as indicative of a forested glacial period were criticised based on the ecology and age control. Here we present new palaeoecological data from a lake located less than 10 km away from Mera. Sediment cores raised from Laguna Pindo (1250 masl; 1°27′S, 78°05′W have been shown to span the late last glacial period [50–13 cal kyr BP (calibrated kiloyears before present]. The palaeoecological information obtained from Laguna Pindo indicate that the region was characterised by a relatively stable plant community, formed by taxa nowadays common at both mid and high elevations. Miconia was the dominant taxon until around 30 cal kyr BP, when it was replaced by Hedyosmum, Asteraceae and Ilex among other taxa. Heat intolerant taxa including Podocarpus, Alnus, and Myrica peaked around the onset of the Last Glacial Maximum (c. 21 cal kyr BP. The results

  9. Three new species of Pristimantis (Lissamphibia, Anura from montane forests of the Cordillera Yanachaga in Central Peru

    Directory of Open Access Journals (Sweden)

    William E. Duellman

    2007-12-01

    Full Text Available We describe three additional new species of Pristimantis from the Cordillera Yanachaga, a part of the Andes in central Peru. Analyses of DNA sequences of the mitochondrial rRNA genes show that onespecies is a close relative of P. bipunctatus (P. conspicillatus Group, another is a close relative of P. stictogaster (P. peruvianus Group, and the third is related to several species in the P. unistrigatus Group. The first two species are morphologically similar to their closest relatives but occur at lower elevations. Twenty-nine species of Pristimantis and Phrynopus are known from the vicinity of the Cordillera Yanachaga. The number of species, especially of Pristimantis, is high in the humid montane forestin comparison with other sites in humid montane forests in Peru, but the number is lower than on the western slopes of the Andes in Ecuador.

  10. Streamflow and water-quality data for Meadow Run Basin, Fayette County, Pennsylvania, December 1987-November 1988. Open file report

    International Nuclear Information System (INIS)

    Kostelnik, K.M.; Witt, E.C.

    1989-01-01

    Streamflow and water-quality data were collected throughout the Meadow Run basin, Fayette County, Pennsylvania, from December 7, 1987 through November 15, 1988, to determine the prevailing quality of surface water over a range of hydrologic conditions. The data will assist the Pennsylvania Department of Environmental Resources during its review of coal-mine permit applications. A water-quality station near the mouth of Meadow Run provided continuous-record of stream stage, pH, specific conductance, and water temperature. Monthly water-quality samples collected at the station were analyzed for total and dissolved metals, nutrients, major cations and anions, and suspended-sediment concentrations

  11. Characterization of a Highly Biodiverse Floodplain Meadow Using Hyperspectral Remote Sensing within a Plant Functional Trait Framework

    Directory of Open Access Journals (Sweden)

    Suvarna Punalekar

    2016-02-01

    Full Text Available We assessed the potential for using optical functional types as effective markers to monitor changes in vegetation in floodplain meadows associated with changes in their local environment. Floodplain meadows are challenging ecosystems for monitoring and conservation because of their highly biodiverse nature. Our aim was to understand and explain spectral differences among key members of floodplain meadows and also characterize differences with respect to functional traits. The study was conducted on a typical floodplain meadow in UK (MG4-type, mesotrophic grassland type 4, according to British National Vegetation Classification. We compared two approaches to characterize floodplain communities using field spectroscopy. The first approach was sub-community based, in which we collected spectral signatures for species groupings indicating two distinct eco-hydrological conditions (dry and wet soil indicator species. The other approach was “species-specific”, in which we focused on the spectral reflectance of three key species found on the meadow. One herb species is a typical member of the MG4 floodplain meadow community, while the other two species, sedge and rush, represent wetland vegetation. We also monitored vegetation biophysical and functional properties as well as soil nutrients and ground water levels. We found that the vegetation classes representing meadow sub-communities could not be spectrally distinguished from each other, whereas the individual herb species was found to have a distinctly different spectral signature from the sedge and rush species. The spectral differences between these three species could be explained by their observed differences in plant biophysical parameters, as corroborated through radiative transfer model simulations. These parameters, such as leaf area index, leaf dry matter content, leaf water content, and specific leaf area, along with other functional parameters, such as maximum carboxylation capacity

  12. Using MODIS data for understanding changes in seagrass meadow health: a case study in the Great Barrier Reef (Australia).

    Science.gov (United States)

    Petus, Caroline; Collier, Catherine; Devlin, Michelle; Rasheed, Michael; McKenna, Skye

    2014-07-01

    Stretching more than 2000 km along the Queensland coast, the Great Barrier Reef Marine Park (GBR) shelters over 43,000 square km of seagrass meadows. Despite the status of marine protected area and World Heritage listing of the GBR, local seagrass meadows are under stress from reduced water quality levels; with reduction in the amount of light available for seagrass photosynthesis defined as the primary cause of seagrass loss throughout the GBR. Methods have been developed to map GBR plume water types by using MODIS quasi-true colour (hereafter true colour) images reclassified in function of their dominant colour. These data can be used as an interpretative tool for understanding changes in seagrass meadow health (as defined in this study by the seagrass area and abundance) at different spatial and temporal scales. We tested this method in Cleveland Bay, in the northern GBR, where substantial loss in seagrass area and biomass was detected by annual monitoring from 2007 to 2011. A strong correlation was found between bay-wide seagrass meadow area and biomass and exposure to turbid Primary (sediment-dominated) water type. There was also a strong correlation between the changes of biomass and area of individual meadows and exposure of seagrass ecosystems to Primary water type over the 5-year period. Seagrass meadows were also grouped according to the dominant species within each meadow, irrespective of location within Cleveland Bay. These consolidated community types did not correlate well with the exposure to Primary water type, and this is likely to be due to local environmental conditions with the individual meadows that comprise these groupings. This study proved that remote sensing data provide the synoptic window and repetitivity required to investigate changes in water quality conditions over time. Remote sensing data provide an opportunity to investigate the risk of marine-coastal ecosystems to light limitation due to increased water turbidity when in situ

  13. Temporal Activity Patterns of the Spider Wasp Pepsis montezuma Smith (Hymenoptera: Pompilidae) in a Disturbed Lower Montane Rainforest (Manizales, Colombia)

    OpenAIRE

    Restrepo-Giraldo, Carlos; Rodriguez, Juanita; Pitts, James P.

    2012-01-01

    We studied the temporal activity pattern of the spider wasp Pepsis montezuma Smith (Hymenoptera: Pompilidae) in a disturbed lower montane rainforest, which is located in the city of Manizales, Colombia, at an altitude of 2,150 m. Females of this species are diurnal with two peaks of activity: one in the morning and the other in the afternoon. During the morning, nectar foraging occurred at Baccharis latifolia. During the afternoon, females hunted for tarantulas of the genus Pamphobeteus (Aran...

  14. A comparison of alpha and beta diversity patterns of ferns, bryophytes and macrolichens in tropical montane forests of southern Ecuador

    OpenAIRE

    Mandl, N A; Lehnert, M; Kessler, M; Gradstein, S R

    2010-01-01

    We present a first comparison of patterns of alpha and beta diversity of ferns, mosses, liverworts and macrolichens in neotropical montane rainforests, and explore the question whether specific taxa may be used as surrogates for others. In three localities in southern Ecuador, we surveyed terrestrial and epiphytic species assemblages in ridge and slope forests in 28 plots of 400 m² each. The epiphytic habitat was significantly richer in ferns, liverworts, and macrolichens than the terrestrial...

  15. Tertiary montane origin of the Central Asian flora, evidence inferred from cpDNA sequences of Atraphaxis (Polygonaceae)

    Science.gov (United States)

    Ming-Li Zhang; Stewart C. Sanderson; Yan-Xia Sun; Byalt V. Vyacheslav; Xiao-Li Hao

    2014-01-01

    Atraphaxis has approximately 25 species and a distribution center in Central Asia. It has been previously used to hypothesize an origin from montane forest. We sampled 18 species covering three sections within the genus and sequenced five cpDNA spacers, atpB-rbcL, psbK-psbI, psbAtrnH, rbcL, and trnL-trnF. BEAST was used to reconstruct phylogenetic relationship and time...

  16. Predicted macroinvertebrate response to water diversion from a montane stream using two-dimensional hydrodynamic models and zero flow approximation

    Science.gov (United States)

    Holmquist, Jeffrey G.; Waddle, Terry J.

    2013-01-01

    We used two-dimensional hydrodynamic models for the assessment of water diversion effects on benthic macroinvertebrates and associated habitat in a montane stream in Yosemite National Park, Sierra Nevada Mountains, CA, USA. We sampled the macroinvertebrate assemblage via Surber sampling, recorded detailed measurements of bed topography and flow, and coupled a two-dimensional hydrodynamic model with macroinvertebrate indicators to assess habitat across a range of low flows in 2010 and representative past years. We also made zero flow approximations to assess response of fauna to extreme conditions. The fauna of this montane reach had a higher percentage of Ephemeroptera, Plecoptera, and Trichoptera (%EPT) than might be expected given the relatively low faunal diversity of the study reach. The modeled responses of wetted area and area-weighted macroinvertebrate metrics to decreasing discharge indicated precipitous declines in metrics as flows approached zero. Changes in area-weighted metrics closely approximated patterns observed for wetted area, i.e., area-weighted invertebrate metrics contributed relatively little additional information above that yielded by wetted area alone. Loss of habitat area in this montane stream appears to be a greater threat than reductions in velocity and depth or changes in substrate, and the modeled patterns observed across years support this conclusion. Our models suggest that step function losses of wetted area may begin when discharge in the Merced falls to 0.02 m3/s; proportionally reducing diversions when this threshold is reached will likely reduce impacts in low flow years.

  17. Population Trends of Central European Montane Birds Provide Evidence for Adverse Impacts of Climate Change on High-Altitude Species.

    Directory of Open Access Journals (Sweden)

    Jiří Flousek

    Full Text Available Climate change is among the most important global threats to biodiversity and mountain areas are supposed to be under especially high pressure. Although recent modelling studies suggest considerable future range contractions of montane species accompanied with increased extinction risk, data allowing to test actual population consequences of the observed climate changes and identifying traits associated to their adverse impacts are very scarce. To fill this knowledge gap, we estimated long-term population trends of montane birds from 1984 to 2011 in a central European mountain range, the Giant Mountains (Krkonoše, where significant warming occurred over this period. We then related the population trends to several species' traits related to the climate change effects. We found that the species breeding in various habitats at higher altitudes had more negative trends than species breeding at lower altitudes. We also found that the species moved upwards as a response to warming climate, and these altitudinal range shifts were associated with more positive population trends at lower altitudes than at higher altitudes. Moreover, long-distance migrants declined more than residents or species migrating for shorter distances. Taken together, these results indicate that the climate change, besides other possible environmental changes, already influences populations of montane birds with particularly adverse impacts on high-altitude species such as water pipit (Anthus spinoletta. It is evident that the alpine species, predicted to undergo serious climatically induced range contractions due to warming climate in the future, already started moving along this trajectory.

  18. Assessment of the impact of anthropic activities on carbon storage in soils of high montane ecosystems in Colombia

    Directory of Open Access Journals (Sweden)

    Orlando Zúñiga-Escobar

    2013-04-01

    Full Text Available The organic carbon in the soil was quantified to assess the impact of anthropic activities on montane ecosystems in Colombia in Chingaza Parque Nacional Natural (PNN and Los Nevados Parque Nacional Natural (PNN . For the development of the soil samples, a detailed in situ description of the edaphological profile of four ecosystems of paramo and high Andean forest areas, of both disturbed and undisturbed zones, was taken as the base. The calculation of the amount of total carbon stored by the soil profile shows that, in Colombia, undisturbed high montane ecosystems (520.9 t ha-1 in paramos and 323.6 t ha-1 in high Andean forests of Chingaza PNN , and 373.0 t ha-1 in paramos and 254.6 t ha-1 in high Andean forests of Los Nevados PNN currently have more carbon than disturbed ecosystems (135.1 t ha-1 in paramos and 141.5 t ha-1 in high Andean forests of Chingaza PNN , and 356.3 t ha-1 in paramos and 217.1 t ha-1 in high Andean forests of Los Nevados PNN . It is clear that the disturbance of high montane ecosystems decreases the amount of carbon in the soil, a situation that is more concerning in Chingaza PNN where the difference between the disturbed and undisturbed ecosystems is much more marked than in Los Nevados PNN

  19. Disentangling the role of management, vegetation structure, and plant quality for Orthoptera in lowland meadows.

    Science.gov (United States)

    Schirmel, Jens; Gerlach, Rebekka; Buhk, Constanze

    2017-08-17

    Seminatural grasslands provide habitats for various species and are important for biodiversity conservation. The understanding of the diverse responses of species and traits to different grassland management methods is therefore urgently needed. We disentangled the role of grassland management (fertilization and irrigation), vegetation structure (biomass, sward height) and plant quality (protein and fiber content) for Orthoptera communities in lowland hay meadows in Germany. We found vegetation structure to be the most important environmental category in explaining community structure of Orthoptera (species richness, total individuals, functional diversity and species composition). Intensively used meadows (fertilized, irrigated, high plant biomass) were characterized by assemblages with few species, low functional diversity, and low conservation value. Thereby, the relatively moderate fertilizer inputs in our study system of up to ∼75 kg N/ha/year reduced functional diversity of Orthoptera, while this negative effect of fertilization was not detectable when solely considering taxonomic aspects. We found strong support for a prominent role of plant quality in shaping Orthoptera communities and especially the trait composition. Our findings demonstrate the usefulness of considering both taxonomic and functional components (functional diversity) in biodiversity research and we suggest a stronger involvement of plant quality measures in Orthoptera studies. © 2017 Institute of Zoology, Chinese Academy of Sciences.

  20. Genetic variation and correlation of agronomic traits in meadow bromegrass (Bromus riparius Rehm clones

    Directory of Open Access Journals (Sweden)

    Araújo Marcelo Renato Alves de

    2004-01-01

    Full Text Available Meadow bromegrass (Bromus riparius Rehm. is a recently introduced pasture grass in western Canada. Its leafy production and rapid regrowth have made it a major grass species for pasturing beef animals in this region. As relatively little breeding work has been done on this species, there is little information on its breeding behaviour. The main objective of this study was to estimate total genetic variability, broad-sense heritability, phenotypic and genetic correlations. Forty-four meadow bromegrass clones were evaluated for agronomic characters. Genetic variation for dry matter yield, seed yield, fertility index, harvest index, plant height, plant spread, crude protein, neutral detergent fiber and acid detergent fiber, was significant. Broad-sense heritability estimates exceeded 50% for all characters. Heritability estimates were at least 3.5 times greater than their standard errors. Phenotypic and genetic correlation between all possible characters were measured. There was general agreement in both sign and magnitude between genetic and phenotypic correlations. Correlations between the different characters demonstrated that it is possible to simultaneously improve seed and forage yield. Based on the results, it appears that the development of higher yielding cultivars with higher crude protein, and lower acid and neutral detergent fibers concentration should be possible.

  1. Nutrient Enrichment Mediates the Relationships of Soil Microbial Respiration with Climatic Factors in an Alpine Meadow

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    Ning Zong

    2015-01-01

    Full Text Available Quantifying the effects of nutrient additions on soil microbial respiration (Rm and its contribution to soil respiration (Rs are of great importance for accurate assessment ecosystem carbon (C flux. Nitrogen (N addition either alone (coded as LN and HN or in combination with phosphorus (P (coded as LN + P and HN + P were manipulated in a semiarid alpine meadow on the Tibetan Plateau since 2008. Either LN or HN did not affect Rm, while LN + P enhanced Rm during peak growing periods, but HN + P did not affect Rm. Nutrient addition also significantly affected Rm/Rs, and the correlations of Rm/Rs with climatic factors varied with years. Soil water content (Sw was the main factor controlling the variations of Rm/Rs. During the years with large rainfall variations, Rm/Rs was negatively correlated with Sw, while, in years with even rainfall, Rm/Rs was positively correlated with Sw. Meanwhile, in N + P treatments the controlling effects of climatic factors on Rm/Rs were more significant than those in CK. Our results indicate that the sensitivity of soil microbes to climatic factors is regulated by nutrient enrichment. The divergent effects of Sw on Rm/Rs suggest that precipitation distribution patterns are key factors controlling soil microbial activities and ecosystem C fluxes in semiarid alpine meadow ecosystems.

  2. The size structure of ramets in Dianthus superbus L. in mosaic meadow vegetation

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    Kinga Kostrakiewicz-Gierałt

    2013-10-01

    Full Text Available The present investigations were carried out in the years 2010–2012 in Kraków-Opatkowice (Southern Poland. The observations were conducted in patches of abandoned Molinietum caeruleae meadows with different dominant species. Patch LM was dominated by low meadow species, forming small procumbent shoots and delicate belowground organs; patch TM was occupied by tall-growing taxa creating large tussocks or robust rhizomes; patch SH was overgrown by shrubs and trees with wide spreading roots. In all patches, the number of ramet clusters of Dianthus superbus was low and constant during the whole study period. All populations showed signs of advanced senility due to the absence of individuals in pre-reproductive stages and the occurrence of generative ramet clusters only. The total number of aboveground units per ramet cluster declined, while the leaf length, height of vegetative and generative stems as well as the size of inflorescences and flowers increased from patch LM to patch TM to patch SH. The presented results provide valuable data concerning the state of ramet clusters studied and their prospects for survival in inhabited sites.

  3. Dominance of the multicoloured Asian lady beetle Harmonia axyridis in an undisturbed wild meadow ecosystem

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    Élise Bélanger

    2011-12-01

    Full Text Available Fifteen years after its arrival in Quebec (Canada, the multicoloured Asian lady beetle Harmonia axyridis (Pallas 1773 (Coleoptera: Coccinellidae has become one of the dominant coccinellid species in agricultural, forested and urban areas. Several studies conducted in North American agricultural ecosystems show that the arrival of H. axyridis and other exotic coccinellid species was followed by decreases in the populations of native coccinellid species. In this study, the abundances of H. axyridis and other native and exotic species were determined in an undisturbed wild meadow located in a protected area. In 2009 and 2010, mainly Solidago canadensis L. (Asteraceae and Asclepias syriaca L. (Asclepiadaceae infested with aphids were surveyed. A total of 1522 individuals, belonging to seven different species, were recorded. In 2009, on all the plants monitored, H. axyridis was clearly the dominant species (69% of the coccinellid assemblage. In addition, this exotic species constituted 84% of the coccinellid assemblage, including Propylea quatuordecimpunctata (L. and Coccinella septempunctata (L. It is likely the dominance of the eurytopic Asian lady beetle in agricultural, forested, urban and undisturbed open ecosystems, poses a threat to native lady beetles. These results also provide evidence that undisturbed wild meadow ecosystems will not constitute a natural refuge from Harmonia axyridis for native species of lady beetles.

  4. A test of the herbivore optimization hypothesis using muskoxen and a graminoid meadow plant community

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    David L. Smith

    1996-01-01

    Full Text Available A prediction from the herbivore optimization hypothesis is that grazing by herbivores at moderate intensities will increase net above-ground primary productivity more than at lower or higher intensities. I tested this hypothesis in an area of high muskox {Ovibos moschatus density on north-central Banks Island, Northwest Territories, Canada (73°50'N, 119°53'W. Plots (1 m2 in graminoid meadows dominated by cottongrass (Eriophorum triste were either clipped, exposed to muskoxen, protected for part of one growing season, or permanently protected. This resulted in the removal of 22-44%, 10-39%, 0-39% or 0%, respectively, of shoot tissue during each growing season. Contrary to the predictions of the herbivore optimization hypothesis, productivity did not increase across this range of tissue removal. Productivity of plants clipped at 1.5 cm above ground once or twice per growing season, declined by 60+/-5% in 64% of the tests. The productivity of plants grazed by muskoxen declined by 56+/-7% in 25% of the tests. No significant change in productivity was observed in 36% and 75% of the tests in clipped and grazed treatments, respecrively. Clipping and grazing reduced below-ground standing crop except where removals were small. Grazing and clipping did not stimulate productivity of north-central Banks Island graminoid meadows.

  5. Effects of Water and Nitrogen Addition on Ecosystem Carbon Exchange in a Meadow Steppe

    Science.gov (United States)

    Wang, Yunbo; Jiang, Qi; Yang, Zhiming; Sun, Wei; Wang, Deli

    2015-01-01

    A changing precipitation regime and increasing nitrogen deposition are likely to have profound impacts on arid and semiarid ecosystem C cycling, which is often constrained by the timing and availability of water and nitrogen. However, little is known about the effects of altered precipitation and nitrogen addition on grassland ecosystem C exchange. We conducted a 3-year field experiment to assess the responses of vegetation composition, ecosystem productivity, and ecosystem C exchange to manipulative water and nitrogen addition in a meadow steppe. Nitrogen addition significantly stimulated aboveground biomass and net ecosystem CO2 exchange (NEE), which suggests that nitrogen availability is a primary limiting factor for ecosystem C cycling in the meadow steppe. Water addition had no significant impacts on either ecosystem C exchange or plant biomass, but ecosystem C fluxes showed a strong correlation with early growing season precipitation, rather than whole growing season precipitation, across the 3 experimental years. After we incorporated water addition into the calculation of precipitation regimes, we found that monthly average ecosystem C fluxes correlated more strongly with precipitation frequency than with precipitation amount. These results highlight the importance of precipitation distribution in regulating ecosystem C cycling. Overall, ecosystem C fluxes in the studied ecosystem are highly sensitive to nitrogen deposition, but less sensitive to increased precipitation. PMID:26010888

  6. Changes in vegetation and soil seed bank of meadow after waterlogging caused by Castor fiber

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    Magdalena Franczak

    2015-07-01

    Full Text Available Soil waterlogging is among abiotic stresses that influence species composition and productivity in numerous plant communities. The aim of the study was to find answer to the question of how waterlogging caused by beavers’ activity induces quantitative and qualitative changes of vegetation and soil seed bank levels of variable-moist meadows. An immediate effect of the waterlogging at the level of vegetation was the decline in species richness and a decrease in the values of the biodiversity index. Water stress inhibited growth and development of plants already present and, primarily, impeded recruitment of new individuals of species characteristic of variable-moist meadows, e.g. Cirsium rivulare, Filipendula ulmaria and Lythrum salicaria, which were replaced by Carex acutiformis. Prolonged waterlogging did not induce equally substantial changes in the soil seed bank as in the vegetation. Both in the waterlogged and control patches, slightly decreased species richness and biodiversity index were recorded. After waterlogging withdrawal, the reserves of the soil seed bank were slightly higher than the initial values. The differences were not statistically significant. In the waterlogged patch, the qualitative floristic similarity between taxa identified in the soil seed bank and vegetation cover declined, which was evidenced by the value of Jaccard’s index decreasing from 0.46 to 0.36. A reverse relationship was found in control patch, where the value of the similarity index slightly increased from 0.41 to 0.48.

  7. Spatially characterizing visitor use and its association with informal trails in Yosemite Valley meadows.

    Science.gov (United States)

    Walden-Schreiner, Chelsey; Leung, Yu-Fai

    2013-07-01

    Ecological impacts associated with nature-based recreation and tourism can compromise park and protected area goals if left unrestricted. Protected area agencies are increasingly incorporating indicator-based management frameworks into their management plans to address visitor impacts. Development of indicators requires empirical evaluation of indicator measures and examining their ecological and social relevance. This study addresses the development of the informal trail indicator in Yosemite National Park by spatially characterizing visitor use in open landscapes and integrating use patterns with informal trail condition data to examine their spatial association. Informal trail and visitor use data were collected concurrently during July and August of 2011 in three, high-use meadows of Yosemite Valley. Visitor use was clustered at statistically significant levels in all three study meadows. Spatial data integration found no statistically significant differences between use patterns and trail condition class. However, statistically significant differences were found between the distance visitors were observed from informal trails and visitor activity type with active activities occurring closer to trail corridors. Gender was also found to be significant with male visitors observed further from trail corridors. Results highlight the utility of integrated spatial analysis in supporting indicator-based monitoring and informing management of open landscapes. Additional variables for future analysis and methodological improvements are discussed.

  8. Seasonal and annual variation in activity in wild male meadow voles (microtus pennsylvanicus)

    International Nuclear Information System (INIS)

    Turner, B.N.; Iverson, S.L.; Severson, K.L.

    1980-10-01

    Project ZEUS was designed to characterize the effects of long-term gamma irradiation on free-ranging meadow voles, and to determine the lowest level of radiation at which biological effects are discernible in the population. Behavioural tests are considered important since recent testing has shown that behavioural effects occur at lower levels of a given toxicant than do pathological ones, and radiation effects may be similar. Overnight activity of wild male voles was investigated to see whether sufficient variability exists in this activity to suggest its retention as a routine test of these irradiated animals. Variables determined included number of activity periods, total amount of activity, and statistical measures derived from these. Results from nearly 2500 activity tests recorded during a seven-year period indicated the annual pattern of activity is more closely associated with the photo-period than to reproductive maturity. There was little variability in activity among years, limiting the usefulness of this test in the context of Project ZEUS, and further suggesting behaviour may have little relationship to the population density fluctuations occurring in meadow voles. Consequently, the recording of this behaviour has been terminated in favour of emphasizing aggression and open-field tests as the behavioural component of the Project ZEUS. (auth)

  9. Application of queuing theory to a fast food outfit: a study of blue meadows restaurant

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    Seigha Gumus

    2017-06-01

    Full Text Available The study evaluated the queuing system in Blue Meadows restaurant with a view to determining its operating characteristics and to improve customers’ satisfaction during waiting time using the lens of queuing theory. Data was obtained from a fast food restaurant in the University of Benin. The data collected was tested to show if it follows a Poisson and exponential distribution of arrival and service rate using chi square goodness of fit. A 95% confidence interval level was used to show the range of customers that come into the system at an hour time frame and the range of customers served at an hour time frame. Using the M/M/s model, the arrival rate, service rate, utilization rate, waiting time in the queue and the probability of customers likely balking from the restaurant was derived. The arrival rate (λ at Blue Meadows restaurant was about 40 customers per hour, while the service rate was about 22 customers per hour per server. The number of servers present in the system was two. The average number of customers in the system in an hour window was 40 customers with a utilization rate of 0.909. The paper concludes with a discussion on the benefits of performing queuing analysis to a restaurant.

  10. Spatially Characterizing Visitor Use and Its Association with Informal Trails in Yosemite Valley Meadows

    Science.gov (United States)

    Walden-Schreiner, Chelsey; Leung, Yu-Fai

    2013-07-01

    Ecological impacts associated with nature-based recreation and tourism can compromise park and protected area goals if left unrestricted. Protected area agencies are increasingly incorporating indicator-based management frameworks into their management plans to address visitor impacts. Development of indicators requires empirical evaluation of indicator measures and examining their ecological and social relevance. This study addresses the development of the informal trail indicator in Yosemite National Park by spatially characterizing visitor use in open landscapes and integrating use patterns with informal trail condition data to examine their spatial association. Informal trail and visitor use data were collected concurrently during July and August of 2011 in three, high-use meadows of Yosemite Valley. Visitor use was clustered at statistically significant levels in all three study meadows. Spatial data integration found no statistically significant differences between use patterns and trail condition class. However, statistically significant differences were found between the distance visitors were observed from informal trails and visitor activity type with active activities occurring closer to trail corridors. Gender was also found to be significant with male visitors observed further from trail corridors. Results highlight the utility of integrated spatial analysis in supporting indicator-based monitoring and informing management of open landscapes. Additional variables for future analysis and methodological improvements are discussed.

  11. Herbivory more limiting than competition on early and established native plants in an invaded meadow.

    Science.gov (United States)

    Gonzales, Emily K; Arcese, Peter

    2008-12-01

    The dominance of nonnative plants coupled with declines of native plants suggests that competitive displacement drives extinctions, yet empirical examples are rare. Herbivores, however, can alter vegetation structure and reduce diversity when abundant. Herbivores may act on mature, reproductive life stages whereas some of the strongest competitive effects might occur at early life stages that are difficult to observe. For example, competition by perennial nonnative grasses can interfere with the establishment of native seeds. We contrasted the effects of ungulate herbivory and competition by neighboring plants on the performance of native plant species at early and established life stages in invaded oak meadows. We recorded growth, survival, and flowering in two native species transplanted as established plants, six native species grown from seed, and five extant lily species as part of two 2 x 2 factorial experiments that manipulated herbivory and competition. Herbivory reduced the performance of nearly all focal native species at early and established life stages, whereas competition had few measurable effects. Our results suggest that herbivory has a greater local influence on native plant species than competition and that reducing herbivore impacts will be required to successfully restore endangered oak meadows where ungulates are now abundant.

  12. Ecohydrology of an Embanked Lowland UK River Meadow and the Effects of Embankment Removal

    Science.gov (United States)

    Clilverd, H.; Thompson, J.; Sayer, C.; Heppell, K.; Axmacher, J.

    2012-12-01

    Pristine riparian and floodplain ecosystems are in a state of dynamic balance due to the regular floods that continuously reshape river channels and their banks, and transport water, sediment and nutrients onto the floodplain. However, the natural flow regime of many rivers has been altered by channelization and artificial embankments designed to protect agricultural and urban developments from flooding. This has had a lasting impact on the hydrological characteristics of floodplain ecosystems and the biological communities that inhabit them. Floodplain restoration, through embankment removal and the reconfiguration of river channels, is now being increasingly employed to re-establish river-floodplain connections and assist the recovery of lost or declining species. In order to manage a river restoration site for plant biodiversity, it is necessary to understand the physical and nutritional status of the root environment. We conducted fine scale (10 × 10 m) botanical and chemical sampling on a 3 ha embanked grassland meadow in Norfolk (Eastern England) and assessed the spatial pattern of plant communities in relation to soil physicochemical conditions. Continuous measurements of groundwater depth and river stage were collectively used to determine changes in the hydrological regime following embankment-removal. Prior to the restoration the meadow plant community was dominated by Holcus lanatus, Ranunculus repens and Agrostis stolonifera. Species richness was fairly low (mean: 8 spp. per m2), and indices of alpha-diversity suggest low heterogeneity of the plant assemblages (mean values for Shannon's Diversity and 1/Simpson's Diversity = 1.4 and 3.4, respectively). Top soils were moderately fertile, with mean respective Olsen P and plant available potassium concentrations of 9.1 mg P kg-1and 1.6 mg K+g-1. Plant available ammonium and nitrate concentrations were on average 31.7 mg NH4+-N kg-1 and 2.8 mg NO3--N kg-1, respectively. River water was enriched in nitrate

  13. The carbon fluxes in different successional stages: modelling the dynamics of tropical montane forests in South Ecuador

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    Sebastian Paulick

    2017-05-01

    Full Text Available Background Tropical forests play an important role in the global carbon (C cycle. However, tropical montane forests have been studied less than tropical lowland forests, and their role in carbon storage is not well understood. Montane forests are highly endangered due to logging, land-use and climate change. Our objective was to analyse how the carbon balance changes during forest succession. Methods In this study, we used a method to estimate local carbon balances that combined forest inventory data with process-based forest models. We utilised such a forest model to study the carbon balance of a tropical montane forest in South Ecuador, comparing two topographical slope positions (ravines and lower slopes vs upper slopes and ridges. Results The simulation results showed that the forest acts as a carbon sink with a maximum net ecosystem exchange (NEE of 9.3 Mg C∙(ha∙yr−1 during its early successional stage (0–100 years. In the late successional stage, the simulated NEE fluctuated around zero and had a variation of 0.77 Mg C∙(ha∙yr –1. The simulated variability of the NEE was within the range of the field data. We discovered several forest attributes (e.g., basal area or the relative amount of pioneer trees that can serve as predictors for NEE for young forest stands (0–100 years but not for those in the late successional stage (500–1,000 years. In case of young forest stands these correlations are high, especially between stand basal area and NEE. Conclusion In this study, we used an Ecuadorian study site as an example of how to successfully link a forest model with forest inventory data, for estimating stem-diameter distributions, biomass and aboveground net primary productivity. To conclude, this study shows that process-based forest models can be used to investigate the carbon balance of tropical montane forests. With this model it is possible to find hidden relationships between forest attributes and forest carbon fluxes

  14. Montane-breeding bird distribution and abundance across national parks of southwestern Alaska

    Science.gov (United States)

    Amundson, Courtney L.; Handel, Colleen M.; Ruthrauff, Daniel R.; Tibbitts, T. Lee; Gill, Robert E.

    2018-01-01

    Between 2004 and 2008, biologists conducted an inventory of breeding birds during May–June primarily in montane areas (>100 m above sea level) in Aniakchak National Monument and Preserve (Aniakchak NMP), Katmai National Park and Preserve (Katmai NPP), and Lake Clark National Park and Preserve (Lake Clark NPP) in southwestern Alaska. Observers conducted 1,021 point counts along 169 transects within 63 10-km × 10-km plots that were randomly selected and stratified by ecological subsection. We created hierarchical N-mixture models to estimate detection probability and abundance for 15 species, including 12 passerines, 2 galliforms, and 1 shorebird. We first modeled detection probability relative to observer, date within season, and proportion of dense vegetation cover around the point, then modeled abundance as a function of land cover composition (proportion of seven coarse-scale land cover types) within 300 m of the survey point. Land cover relationships varied widely among species but most showed selection for low to tall shrubs (0.2–5 m tall) and an avoidance of alpine and 2 dwarf shrub–herbaceous cover types. After adjusting for species not observed, we estimated a minimum of 107 ± 9 species bred in the areas surveyed within the three parks combined. Species richness was negatively associated with elevation and associated land cover types. At comparable levels of survey effort (n = 721 birds detected), species richness was greatest in Lake Clark NPP (75 ± 12 species), lowest in Aniakchak NMP (45 ± 6 species), and intermediate at Katmai NPP (59 ± 10 species). Species richness was similar at equivalent survey effort (n = 973 birds detected) within the Lime Hills, Alaska Range, and Alaska Peninsula ecoregions (68 ± 8; 79 ± 11; 67 ± 11, respectively). Species composition was similar across all three parks and across the three major ecoregions (Alaska Range, Alaska Peninsula, Lime Hills) that encompass them. Our results provide baseline estimates of

  15. Ecology of Mabuya agilis (Squamata: Scincidae from a montane atlantic rainforest area in Southeastern Brazil

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    Teixeira, Rogério L.

    2003-05-01

    Full Text Available Alguns aspectos da ecologia (principalmente reprodução e dieta do lagarto scincídeo Mabuya agilis foram estudados com base em amostras mensais realizadas de dezembro de 1997 a abril de 1999 em uma área de floresta tropical serrana no estado do Espírito Santo, sudeste do Brasil. Dos 197 espécimes coletados, 82 eram machos, 110 eram fêmeas, e o resto não pôde ser corretamente sexado. Lagartos variaram em comprimento rostro-coacal de 30 a 96 mm e foram sexualmente dimórficos em tamanho, com fêmeas atingindo maiores tamanhos que machos. A menor fêmea grávida mediu 54.0 mm. O tamanho da ninhada para 49 fêmeas grávidas variou de 2 a 9 (média = 5.7 e esteve positiva e significativamente relacionado ao tamanho dos lagartos. As presas dominantes na dieta de M. agilis foram baratas, ortópteros e aranhas. A população de M. agilis aqui estudada diferiu de outras populações conspecíficas previamente estudadas em hábitats de «restinga» nos estados do Rio de Janeiro e Espírito Santo, sendo que os indivíduos crescem a tamanhos maiores e a fecundidade é mais alta, possivelmente devido a uma maior disponibilidade de alimento no hábitat de floresta tropical serrana Some aspects of the ecology (mainly reproduction and diet of the skink Mabuya agilis were studied based on monthly samples taken from December 1997 to April 1999 at a montane rainforest area in Espírito Santo state, southeastern Brazil. Of 197 collected specimens, 82 were males, 110 were females, and the rest could not be properly sexed. Lizards varied in snout-vent length (SVL from 30 to 96 mm and were sexually dimorphic in size, with females growing larger than males. The smallest gravid female measured 54.0 mm in SVL. Litter size of 49 gravid females varied from 2 to 9 (mean= 5.7 and was positively and significantly related to lizard SVL. The dominant prey items in the diet of M. agilis were cockroaches, orthopterans and spiders. The population of M. agilis here studied

  16. ¿Quién fue Lluís Montané i Mollfulleda?

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    Ramon Balius i Juli

    2006-06-01

    Full Text Available Lluís Montané i Mollfulleda, nacido en Sant Celoni en 1905, era un artista integral, enmarcado en las corrientes novecentistas y mediterranistas que se sustentan en la tradición clásica del mundo griego. Estudió en la Escuela de Bellas Artes de Barcelona (Llotja entre 1921 y 1927, aunque antes, muy joven, trabajó durante tres años en el taller del escultor Eusebi Arnau (1864-1933. En la Llotja su segundo maestro, después del profesor de primer curso, Parera, fue Antoni Alsina i Amils (1864-1948, el cual, como comentaremos, fue el más apreciado. Montané quiso conocer el mundo de su arte y después de una beca, en 1926, para realizar estudios por España, ganó por concurso, en 1928, una pensión de la Diputación de Barcelona para ampliar estudios en Italia, Francia y Bélgica. En Bélgica estudió de cerca la obra de Constantin Meu­nier (1831-1905. En 1930, en París, frecuentó la Grande Chaumière donde todavía se respiraban les ideas y las directrices de Auguste Rodin (1840-1917 y de Antoine Bourdelle (1861-1929. Antes había estado en Italia, en Florencia y Roma, en la Academia de Bellas Artes de España, al lado del maestro Miquel Blay (1866-1936 en donde, mientras mejoraba su aprendizaje, pudo contemplar en los museos de Roma y Nápoles, las esculturas de los autores clásicos. En 1931 donó a la Generalitat de Catalunya su obra Joguinera (Juguetona realizada durante su estancia por Europa. Esta escultura se ubicó en el despacho del presidente Macià y actualmente se encuentra en el Centro de Cultura Contempo­ránea.

  17. The effects of burning and grazing on soil carbon dynamics in managed Peruvian tropical montane grasslands

    Science.gov (United States)

    Oliver, Viktoria; Oliveras, Imma; Kala, Jose; Lever, Rebecca; Arn Teh, Yit

    2017-12-01

    Montane tropical soils are a large carbon (C) reservoir, acting as both a source and a sink of CO2. Enhanced CO2 emissions originate, in large part, from the decomposition and losses of soil organic matter (SOM) following anthropogenic disturbances. Therefore, quantitative knowledge of the stabilization and decomposition of SOM is necessary in order to understand, assess and predict the impact of land management in the tropics. In particular, labile SOM is an early and sensitive indicator of how SOM responds to changes in land use and management practices, which could have major implications for long-term carbon storage and rising atmospheric CO2 concentrations. The aim of this study was to investigate the impacts of grazing and fire history on soil C dynamics in the Peruvian montane grasslands, an understudied ecosystem, which covers approximately a quarter of the land area in Peru. A density fractionation method was used to quantify the labile and stable organic matter pools, along with soil CO2 flux and decomposition measurements. Grazing and burning together significantly increased soil CO2 fluxes and decomposition rates and reduced temperature as a driver. Although there was no significant effect of land use on total soil C stocks, the combination of burning and grazing decreased the proportion of C in the free light fraction (LF), especially at the lower depths (10-20 and 20-30 cm). In the control soils, 20 % of the material recovered was in the free LF, which contained 30 % of the soil C content. In comparison, the burnt-grazed soil had the smallest recovery of the free LF (10 %) and a significantly lower C content (14 %). The burnt soils had a much higher proportion of C in the occluded LF (12 %) compared to the not-burnt soils (7 %) and there was no significant difference among the treatments in the heavy fraction (F) ( ˜ 70 %). The synergistic effect of burning and grazing caused changes to the soil C dynamics. CO2 fluxes were increased and the dominant

  18. Wetland and floodplain habitats management and solutions in Lower Meadow of Prut Natural Park

    Directory of Open Access Journals (Sweden)

    Florin VARTOLOMEI

    2013-04-01

    Full Text Available The pressure of economic development from the last 50 years in the area of Prut river, the protection measures against floods by building dams in the major river bed and the building of the hydrotechnical knot Stânca-Costeşti have been the causes of the transformation of the typical habitats in the humid areas at the border of Prut river, thus of the flood area favouring the breeding of fish and birds, endangering the ecological integrity of the area eco-system complex.In the past, Romanian Waters National Company the main manager of the water resources from Romania has started the preparation at the request of the Ministry of Water Forest and Environment Protection the inventory of the wetland and floodplains at national level, including the potential for restoration according with the particular case from Romania, where the process of land restitution to the previous owners is one important problem even in present time.In Prut catchment area is presented a large number of existing wetlands with a large restoration potential (about 200 wetlands recorded for whole Prut basin, many of them are less than 1 sqkm surface.It has to be mentioned that several wetlands which in present are in natural stage are included or will be included in the List of Protected Areas under the legislation preservation. In this regard the planning of wetlands and floodplains rehabilitation is underdevelopment and will depend by the finalization of the land restitution action.For all the types of existing habitats housing a large variety of fauna (especially avifauna, sedentary as well as migrating or passing fauna, the Maţa – Rădeanu humid area, with a surface of 386 ha, is similar to the special preservation areas from the Danube Delta.Among the protected areas within lower Prut basin, according to the criteria of habitat identification, three of them (Ostrovul Prut, Lower Prut river meadow and Vlascuta swamp have been indicated to include some wetlands as well

  19. Alluvial Mountain Meadow Source-Sink Dynamics: Land-Cover Effects on Water and Fluvial Carbon Export

    Science.gov (United States)

    Weiss, T.; Covino, T. P.; Wohl, E.; Rhoades, C.; Fegel, T.; Clow, D. W.

    2017-12-01

    Fluvial networks of historically glaciated mountain landscapes alternate between confined and unconfined valley segments. In low-gradient unconfined reaches, river-connected wet meadows commonly establish, and have been recognized as important locations of long-term water, carbon, and nutrient storage. Among connected meadow floodplains, sink-source behavior shifts as a function of flow state; storing water at high flows (snowmelt) and contributing toward higher late-season baseflows. Despite these benefits, historical and contemporary land-use practices often result in the simplification of wet meadow systems, leading to reduced river-floodplain connectivity, lower water-tables and reductions in hydrologic buffering capacity. In this study, we are exploring hydrologic-carbon relationships across a gradient of valley confinement and river-floodplain connectivity (connected, n=3; disconnected, n=4) within the Colorado Rockies. Our approach includes hydrologic analysis, fluorometric assays, water chemistry, instream metabolic measures, and land-cover assessment to examine patterns between land-form, carbon quantity and quality, and stream ecosystem productivity. Between different meadow types, preliminary results suggest differences between instream productivity, carbon qualities, and hydrologic-carbon sink-source dynamics across the season. These data and analyses will provide insight into water, carbon and nutrient flux dynamics as a function of land-cover in mountain headwaters.

  20. Can differences in soil community composition after peat meadow restoration lead to different decomposition and mineralization rates?

    NARCIS (Netherlands)

    Dijk, van J.; Didden, W.A.M.; Kuenen, F.; Bodegom, van P.M.; Verhoef, H.A.; Aerts, R.

    2009-01-01

    Reducing decomposition and mineralization of organic matter by increasing groundwater levels is a common approach to reduce plant nutrient availability in many peat meadow restoration projects. The soil community is the main driver of these processes, but how community composition is affected by

  1. Altered precipitation patterns and simulated nitrogen deposition effects on phenology of common plant species in a Tibetan Plateau alpine meadow

    Science.gov (United States)

    The interactive effects of five seasonal precipitation distribution patterns and two levels of N deposition (ambient and doubled) on phenological traits of six dominant plant species were studied in an alpine meadow of the Tibetan Plateau for two consecutive years. Seasonal precipitation patterns i...

  2. Mediating water temperature increases due to livestock and global change in high elevation meadow streams of the Golden Trout Wilderness

    Science.gov (United States)

    Sebastien Nussle; Kathleen R. Matthews; Stephanie M. Carlson

    2015-01-01

    Rising temperatures due to climate change are pushing the thermal limits of many species, but how climate warming interacts with other anthropogenic disturbances such as land use remains poorly understood. To understand the interactive effects of climate warming and livestock grazing on water temperature in three high elevation meadow streams in the Golden Trout...

  3. Climatic, landform, microtopographic, and overstory canopy controls of tree invasion in a subalpine meadow landscape, Oregon Cascades, USA

    Science.gov (United States)

    Harold S.J. Zald; Thomas A. Spies; Manuela Huso; Demetrios. Gatziolis

    2012-01-01

    Tree invasions have been documented throughout Northern Hemisphere high elevation meadows, as well as globally in many grass and forb-dominated ecosystems. Tree invasions are often associated with large-scale changes in climate or disturbance regimes, but are fundamentally driven by regeneration processes influenced by interactions between climatic, topographic, and...

  4. Reparation for a Violent Boyhood: Pedagogies of Mourning in Shane Meadow's "This Is England"

    Science.gov (United States)

    Dyer, Hannah

    2017-01-01

    This article turns to Shane Meadow's film "This is England" (2006) to describe the impact that losing a parent can have on a child's development. In doing so it also, more broadly, makes a case for creative fiction as a resource for teaching about children's mourning. The film's protagonist is a boy named Shaun Fields whose father has…

  5. Microclimate changes in a spruce stand and meadow ecosystem during a solar eclipse in the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Nezval, O.; Pavelka, Marian

    2017-01-01

    Roč. 72, č. 3 (2017), s. 67-72 ISSN 0043-1656 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 ; RVO:86652079 Keywords : Species Index: Picea * meadow ecosystem * Czech Republic * microclima Subject RIV: EH - Ecology, Behaviour OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 0.961, year: 2016

  6. The effects of mountain meadows management on soil fauna communities (on example of earthworms and oribatid mites)

    Czech Academy of Sciences Publication Activity Database

    Pižl, Václav; Starý, Josef

    2001-01-01

    Roč. 7, - (2001), s. 87-96 ISSN 1211-7420 R&D Projects: GA ČR GA206/99/1410 Institutional research plan: CEZ:AV0Z6066911 Keywords : earthworms * oribatid mites * mountain meadows Subject RIV: EH - Ecology, Behaviour

  7. Diversity of Calthion wet meadows in the western part of flysch Carpathians: regional classification based on national formal definitions

    Czech Academy of Sciences Publication Activity Database

    Hájková, Petra; Hájek, Michal

    2005-01-01

    Roč. 15, - (2005), s. 85-116 ISSN 1210-0420 R&D Projects: GA ČR(CZ) GA206/05/0020 Institutional research plan: CEZ:AV0Z60050516 Keywords : meadows * classification * ecology Subject RIV: EF - Botanics

  8. AN INTEGRATED, SCIENCE-BASED APPROACH TO MANAGING AND RESTORING UPLAND RIPARIAN MEADOWS IN THE GREAT BASIN OF CENTRAL NEVADA

    Science.gov (United States)

    Riparian corridor and meadow ecosystems in upland watersheds are of local and regional importance in the Great Basin. Covering only 1-3% of the total land area, these ecosystems contain a disproportionally large percentage of the region's biodiversity. Stream incision is a major ...

  9. A modified MOD16 algorithm to estimate evapotranspiration over alpine meadow on the Tibetan Plateau, China

    Science.gov (United States)

    Chang, Y.; Ding, Y.; Zhao, Q.; Zhang, S.

    2017-12-01

    The accurate estimation of evapotranspiration (ET) is crucial for managing water resources in areas with extreme climates affected by climate change, such as the Tibetan Plateau (TP). The MOD16 ET product has also been validated and applied in many countries with various climates, however, its performance varies under different climates and regions. Several have studied ET based on satellite-based models on the TP. However, only a few studies on the performance of MOD16 in the TP with heterogeneous land cover have been reported. This study proposes an improved algorithm for estimating ET based on a proposed modified MOD16 method over alpine meadow on the TP in China. Wind speed and vegetation height were integrated to estimate aerodynamic resistance, while the temperature and moisture constraint for stomatal conductance were revised based on the technique proposed by Fisher et al. (2008). Moreover, Fisher's method for soil evaporation was introduced to decrease the uncertainty of soil evaporation estimation. Five representative alpine meadow sites on the TP were selected to investigate the performance of the modified algorithm. Comparisons between ET observed using Eddy Covariance (EC) and estimated using both the original method and modified method suggest that the modified algorithm had better performance than the original MOD16 method. This result was achieved considering that the coefficient of determination (R2) increased from 0.28 to 0.70, and the root mean square error (RMSE) decreased from 1.31 to 0.77 mm d-1. The modified algorithm also outperformed on precipitation days compared to non-precipitation days at Suli and Hulugou sites, while it performed well for both non-precipitation and precipitation days at Tanggula site. Comparisons of the 8-day ET estimation using the MOD16 product, original MOD16 method, and modified MOD16 method with observed ET suggest that MOD16 product underestimated ET over the alpine meadow of the TP during the growing season

  10. Effect of environmental factors (wave exposure and depth) and anthropogenic pressure in the C sink capacity of Posidonia oceanica meadows

    KAUST Repository

    Mazarrasa, Iné s; Marbà , Nú ria; Garcia-Orellana, Jordi; Masqué , Pere; Arias-Ortiz, Ariane; Duarte, Carlos M.

    2017-01-01

    Seagrass are among the most important natural carbon sinks on Earth with Posidonia oceanica (Mediterranean Sea) considered as the most relevant species. Yet, the number of direct measurements of organic carbon burial rates in P. oceanica is still scarce and the effect of local environmental factors remains largely unexplored. In addition, P. oceanica meadows are declining due to the increase in anthropogenic pressure in coastal areas during the last century. The aim of this study is to assess the recent carbon sink capacity of P. oceanica and particularly the effect of human pressure and two environmental factors, water depth and exposure to wave energy (based on a fetch index), on the carbon burial rate since 1900. We conducted an extensive survey of sediment cores in meadows distributed across a gradient of depth, fetch, and human pressure around The Balearic Islands. Sediment and carbon accumulation rates were obtained from 210Pb concentrations profiles. Top-30 centimeters carbon stocks (6.1 ± 1.4 kg C m−2) and burial rates (26 ± 6 g C m−2 yr1) varied up to fivefold across meadows. No significant effect of water depth in carbon burial rates was observed. Although fetch was significantly correlated with sediment mean grain size, confirming the effect of wave exposure in the patterns of sedimentation, fetch alone could not explain the differences in carbon burial rates among the meadows examined. Human pressure affected carbon burial rates, leading to increased rates since the onset of the rise in anthropogenic pressure, particularly so in sheltered meadows supporting high human pressure.

  11. Effect of environmental factors (wave exposure and depth) and anthropogenic pressure in the C sink capacity of Posidonia oceanica meadows

    KAUST Repository

    Mazarrasa, Inés

    2017-03-20

    Seagrass are among the most important natural carbon sinks on Earth with Posidonia oceanica (Mediterranean Sea) considered as the most relevant species. Yet, the number of direct measurements of organic carbon burial rates in P. oceanica is still scarce and the effect of local environmental factors remains largely unexplored. In addition, P. oceanica meadows are declining due to the increase in anthropogenic pressure in coastal areas during the last century. The aim of this study is to assess the recent carbon sink capacity of P. oceanica and particularly the effect of human pressure and two environmental factors, water depth and exposure to wave energy (based on a fetch index), on the carbon burial rate since 1900. We conducted an extensive survey of sediment cores in meadows distributed across a gradient of depth, fetch, and human pressure around The Balearic Islands. Sediment and carbon accumulation rates were obtained from 210Pb concentrations profiles. Top-30 centimeters carbon stocks (6.1 ± 1.4 kg C m−2) and burial rates (26 ± 6 g C m−2 yr1) varied up to fivefold across meadows. No significant effect of water depth in carbon burial rates was observed. Although fetch was significantly correlated with sediment mean grain size, confirming the effect of wave exposure in the patterns of sedimentation, fetch alone could not explain the differences in carbon burial rates among the meadows examined. Human pressure affected carbon burial rates, leading to increased rates since the onset of the rise in anthropogenic pressure, particularly so in sheltered meadows supporting high human pressure.

  12. Effects of Reduced Summer Precipitation on Productivity and Forage Quality of Floodplain Meadows at the Elbe and the Rhine River

    Science.gov (United States)

    Ludewig, Kristin; Donath, Tobias W.; Zelle, Bianka; Eckstein, R. Lutz; Mosner, Eva; Otte, Annette; Jensen, Kai

    2015-01-01

    Background Floodplain meadows along rivers are semi-natural habitats and depend on regular land use. When used non-intensively, they offer suitable habitats for many plant species including rare ones. Floodplains are hydrologically dynamic ecosystems with both periods of flooding and of dry conditions. In German floodplains, dry periods may increase due to reduced summer precipitation as projected by climate change scenarios. Against this background, the question arises, how the forage quantity and quality of these meadows might change in future. Methods We report results of two field trials that investigated effects of experimentally reduced summer precipitation on hay quantity and quality of floodplain meadows at the Rhine River (2011-2012) and at two Elbe tributaries (2009-2011). We measured annual yield, the amount of hay biomass, and contents of crude protein, crude fibre, energy, fructan, nitrogen, phosphorus, and potassium. Results The annual yield decreased under precipitation reduction at the Rhine River. This was due to reduced productivity in the second cut hay at the Rhine River in which, interestingly, the contents of nitrogen and crude protein increased. The first cut at the Rhine River was unaffected by the treatments. At the Elbe tributaries, the annual yield and the hay quantity and quality of both cuts were only marginally affected by the treatments. Conclusion We conclude that the yield of floodplain meadows may become less reliable in future since the annual yield decreased under precipitation reduction at the Rhine River. However, the first and agriculturally more important cut was almost unaffected by the precipitation reduction, which is probably due to sufficient soil moisture from winter/spring. As long as future water levels of the rivers will not decrease during spring, at least the use of the hay from the first cut of floodplain meadows appears reliable under climate change. PMID:25950730

  13. Transfer of 137Cs from soil to plants in a wet montane forest in subtropical Taiwan

    International Nuclear Information System (INIS)

    Chih-Yu Chiu

    1999-01-01

    The distribution of 137 Cs in an undisturbed, multistoried, subtropical wet montane forest ecosystem surrounding Yuanyang Lake (lake surface level ca. 1670 m, in northeastern Taiwan), was investigated. The mossy forest here represents a currently-rare perhumid temperate environment in subtropical region. The radioactivity concentration of 137 Cs was determined by γ-spectroscopy with a Ge(Li) detector. Although the soil is extremely acidic (pH 3.3 to 3.6) and the rainfall is high, 137 Cs is evidently retained in the organic layer. The radioactivity concentration of 137 Cs in surface soil ranges from 28 to 71 Bq x kg -1 . The concentrations of 137 Cs in the ground moss layer and litter were much lower than that in the soil organic layer; this suggests that 137 Cs detected is not from the newly deposited radioactive fallout. The radioactivity concentration and transfer factor (TF) of 137 Cs varied with plant species. Shrubs and ferns have higher values than a coniferous tree (Taiwan cedar). The TF in this ecosystem is as high as 0.21 to 1.88. The high values of TF is attributed to the abundance of the organic matter in the forest soils. The rapid recycling of 137 Cs through the soil-plant system of this undisturbed multistoried ecosystem suggests the existence of an internal cycling that help the accumulation of 137 Cs in this ecosystem. (author)

  14. Classification of Snowfall Events and Their Effect on Canopy Interception Efficiency in a Temperate Montane Forest.

    Science.gov (United States)

    Roth, T. R.; Nolin, A. W.

    2015-12-01

    Forest canopies intercept as much as 60% of snowfall in maritime environments, while processes of sublimation and melt can reduce the amount of snow transferred from the canopy to the ground. This research examines canopy interception efficiency (CIE) as a function of forest and event-scale snowfall characteristics. We use a 4-year dataset of continuous meteorological measurements and monthly snow surveys from the Forest Elevation Snow Transect (ForEST) network that has forested and open sites at three elevations spanning the rain-snow transition zone to the upper seasonal snow zone. Over 150 individual storms were classified by forest and storm type characteristics (e.g. forest density, vegetation type, air temperature, snowfall amount, storm duration, wind speed, and storm direction). The between-site comparisons showed that, as expected, CIE was highest for the lower elevation (warmer) sites with higher forest density compared with the higher elevation sites where storm temperatures were colder, trees were smaller and forests were less dense. Within-site comparisons based on storm type show that this classification system can be used to predict CIE.Our results suggest that the coupling of forest type and storm type information can improve estimates of canopy interception. Understanding the effects of temperature and storm type in temperate montane forests is also valuable for future estimates of canopy interception under a warming climate.

  15. FLORISTIC CHANGES ALONG THE TOPOGRAPHICAL GRADIENT IN MONTANE GRASSLANDS IN MONTI PICENTINI (CAMPANIA, SW ITALY

    Directory of Open Access Journals (Sweden)

    M. CUTINI

    2010-01-01

    Full Text Available Populations of xerotolerant species (Achnatherum calamagrostis, Stipa crassiculmis subsp. picentina, are scattered along a wide altitudinal gradient on slopes at mid- and high elevation in Monti Picentini, a subcoastal mesozoic limestone ridge in Tyrrhenian Southern Italy. Their stands are widespread in grasslands of mostly secondary origin. At lower altitudes these grasslands replace former deciduous forest communities dominated by oaks or beech, while at higher altitudes they reach the summits, where they apparently merge into the remnants of the still partially grazed, zonal climatogenic, grasslands ranging above the local tree-line. Nevertheless primary stands of these grasslands are to be found around the many clusters of highly dynamic sites of the montane and sub-alpine levels, scattered around screes and rocky outcrops of the prevalently dolomitic morphology of the slopes. This virtual continuity of non arboreal communities across more than 1000 metres of the local topographical gradient, where azonal, relic stands of Pinus nigra s.l. are transitional between the grasslands and the surrounding zonal broadleaved forest vegetation, stresses patterns of the coenological changes between Festuco-Brometea and Elyno-Seslerietea along the catena, which suggest fragmentary persistence of a paleozonation.

  16. FLORISTIC CHANGES ALONG THE TOPOGRAPHICAL GRADIENT IN MONTANE GRASSLANDS IN MONTI PICENTINI (CAMPANIA, SW ITALY

    Directory of Open Access Journals (Sweden)

    F. SPADA

    2010-04-01

    Full Text Available Populations of xerotolerant species (Achnatherum calamagrostis, Stipa crassiculmis subsp. picentina, are scattered along a wide altitudinal gradient on slopes at mid- and high elevation in Monti Picentini, a subcoastal mesozoic limestone ridge in Tyrrhenian Southern Italy. Their stands are widespread in grasslands of mostly secondary origin. At lower altitudes these grasslands replace former deciduous forest communities dominated by oaks or beech, while at higher altitudes they reach the summits, where they apparently merge into the remnants of the still partially grazed, zonal climatogenic, grasslands ranging above the local tree-line. Nevertheless primary stands of these grasslands are to be found around the many clusters of highly dynamic sites of the montane and sub-alpine levels, scattered around screes and rocky outcrops of the prevalently dolomitic morphology of the slopes. This virtual continuity of non arboreal communities across more than 1000 metres of the local topographical gradient, where azonal, relic stands of Pinus nigra s.l. are transitional between the grasslands and the surrounding zonal broadleaved forest vegetation, stresses patterns of the coenological changes between Festuco-Brometea and Elyno-Seslerietea along the catena, which suggest fragmentary persistence of a paleozonation.

  17. Structure of the epiphyte community in a tropical montane forest in SW China.

    Directory of Open Access Journals (Sweden)

    Mingxu Zhao

    Full Text Available Vascular epiphytes are an understudied and particularly important component of tropical forest ecosystems. However, owing to the difficulties of access, little is known about the properties of epiphyte-host tree communities and the factors structuring them, especially in Asia. We investigated factors structuring the vascular epiphyte-host community and its network properties in a tropical montane forest in Xishuangbanna, SW China. Vascular epiphytes were surveyed in six plots located in mature forests. Six host and four micro-site environmental factors were investigated. Epiphyte diversity was strongly correlated with host size (DBH, diameter at breast height, while within hosts the highest epiphyte diversity was in the middle canopy and epiphyte diversity was significantly higher in sites with canopy soil or a moss mat than on bare bark. DBH, elevation and stem height explained 22% of the total variation in the epiphyte species assemblage among hosts, and DBH was the most important factor which alone explained 6% of the variation. Within hosts, 51% of the variation in epiphyte assemblage composition was explained by canopy position and substrate, and the most important single factor was substrate which accounted for 16% of the variation. Analysis of network properties indicated that the epiphyte host community was highly nested, with a low level of epiphyte specialization, and an almost even interaction strength between epiphytes and host trees. Together, these results indicate that large trees harbor a substantial proportion of the epiphyte community in this forest.

  18. Temporal germ cell development strategy during continuous spermatogenesis within the montane lizard, Sceloporus bicanthalis (Squamata; Phrynosomatidae).

    Science.gov (United States)

    Gribbins, Kevin; Anzalone, Marla; Collier, Matthew; Granados-González, Gisela; Villagrán-Santa Cruz, Maricela; Hernández-Gallegos, Oswaldo

    2011-10-01

    Sceloporus bicanthalis is a viviparous lizard that lives at higher elevations in Mexico. Adult male S. bicanthalis were collected (n = 36) from the Nevado de Toluca, Mexico (elevation is 4200 m) during August to December, 2007 and January to July, 2008. Testes were extracted, fixed in Trumps, and dehydrated in a graded series of ethanol. Tissues were embedded, sectioned (2 μm), stained, and examined via a light microscope to determine the spermatogenic developmental strategy of S. bicanthalis. In all months examined, the testes were spermiogenically active; based on this, plus the presence of sperm in the lumina of seminiferous tubules, we inferred that S. bicanthalis had year-round or continuous spermatogenesis, unlike most reptiles that occupy a temperate or montane habitat. It was recently reported that seasonally breeding reptiles had a temporal germ cell development strategy similar to amphibians, where germ cells progress through spermatogenesis as a single population, which leads to a single spermiation event. This was much different than spatial development within the testis of other derived amniotes. We hypothesized that germ cell development was temporal in S. bicanthalis. Therefore, we wanted to determine whether reptiles that practice continuous spermatogenesis have a mammalian-like spatial germ cell development, which is different than the typical temperate reptile exhibiting a temporal development. In the present study, S. bicanthalis had a temporal development strategy, despite its continuous spermatogenic cycle, making them similar to tropical anoles. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. A stand-replacing fire history in upper montane forests of the southern Rocky Mountains

    Science.gov (United States)

    Margolis, E.Q.; Swetnam, T.W.; Allen, Craig D.

    2007-01-01

    Dendroecological techniques were applied to reconstruct stand-replacing fire history in upper montane forests in northern New Mexico and southern Colorado. Fourteen stand-replacing fires were dated to 8 unique fire years (1842–1901) using four lines of evidence at each of 12 sites within the upper Rio Grande Basin. The four lines of evidence were (i) quaking aspen (Populus tremuloides Michx.) inner-ring dates, (ii) fire-killed conifer bark-ring dates, (iii) tree-ring width changes or other morphological indicators of injury, and (iv) fire scars. The annual precision of dating allowed the identification of synchronous stand-replacing fire years among the sites, and co-occurrence with regional surface fire events previously reconstructed from a network of fire scar collections in lower elevation pine forests across the southwestern United States. Nearly all of the synchronous stand-replacing and surface fire years coincided with severe droughts, because climate variability created regional conditions where stand-replacing fires and surface fires burned across ecosystems. Reconstructed stand-replacing fires that predate substantial Anglo-American settlement in this region provide direct evidence that stand-replacing fires were a feature of high-elevation forests before extensive and intensive land-use practices (e.g., logging, railroad, and mining) began in the late 19th century.

  20. Life in the clouds: are tropical montane cloud forests responding to changes in climate?

    Science.gov (United States)

    Hu, Jia; Riveros-Iregui, Diego A

    2016-04-01

    The humid tropics represent only one example of the many places worldwide where anthropogenic disturbance and climate change are quickly affecting the feedbacks between water and trees. In this article, we address the need for a more long-term perspective on the effects of climate change on tropical montane cloud forests (TMCF) in order to fully assess the combined vulnerability and long-term response of tropical trees to changes in precipitation regimes, including cloud immersion. We first review the ecophysiological benefits that cloud water interception offers to trees in TMCF and then examine current climatological evidence that suggests changes in cloud base height and impending changes in cloud immersion for TMCF. Finally, we propose an experimental approach to examine the long-term dynamics of tropical trees in TMCF in response to environmental conditions on decade-to-century time scales. This information is important to assess the vulnerability and long-term response of TMCF to changes in cloud cover and fog frequency and duration.

  1. Structure of the epiphyte community in a tropical montane forest in SW China.

    Science.gov (United States)

    Zhao, Mingxu; Geekiyanage, Nalaka; Xu, Jianchu; Khin, Myo Myo; Nurdiana, Dian Ridwan; Paudel, Ekananda; Harrison, Rhett Daniel

    2015-01-01

    Vascular epiphytes are an understudied and particularly important component of tropical forest ecosystems. However, owing to the difficulties of access, little is known about the properties of epiphyte-host tree communities and the factors structuring them, especially in Asia. We investigated factors structuring the vascular epiphyte-host community and its network properties in a tropical montane forest in Xishuangbanna, SW China. Vascular epiphytes were surveyed in six plots located in mature forests. Six host and four micro-site environmental factors were investigated. Epiphyte diversity was strongly correlated with host size (DBH, diameter at breast height), while within hosts the highest epiphyte diversity was in the middle canopy and epiphyte diversity was significantly higher in sites with canopy soil or a moss mat than on bare bark. DBH, elevation and stem height explained 22% of the total variation in the epiphyte species assemblage among hosts, and DBH was the most important factor which alone explained 6% of the variation. Within hosts, 51% of the variation in epiphyte assemblage composition was explained by canopy position and substrate, and the most important single factor was substrate which accounted for 16% of the variation. Analysis of network properties indicated that the epiphyte host community was highly nested, with a low level of epiphyte specialization, and an almost even interaction strength between epiphytes and host trees. Together, these results indicate that large trees harbor a substantial proportion of the epiphyte community in this forest.

  2. Medicinal and Environmental Indicator Species of Utricularia from Montane Forest of Peninsular Malaysia

    Science.gov (United States)

    Haron, Noorma Wati; Chew, Ming Yee

    2012-01-01

    The carnivorous Utricularia (Lentibulariaceae) is a small herb of multifarious wet habitats worldwide. Eleven of the 14 Peninsular Malaysian species range into the mountains. Distribution, disturbance adaptability and collection frequency were used to formulate their commonness category. Common (U. aurea, U. bifida, and U. minutissima) and fairly common (U. gibba and U. uliginosa) species are mostly lowland plants that ascend to open montane microhabitats, while the fairly common (U. striatula), narrow-range (U. caerulea pink form and U. involvens), rare (U. furcellata and U. scandens), and endemic (U. vitellina) species are restricted to mountainous sites. Common species that colonise dystrophic to oligotrophic man-made sites in late succession could serve as predictors for general health and recovery of wet habitats. Rarer species are often locally abundant, their niches situated around pristine forest edges. When in decline, they indicate the beginning of problems affecting the forest. Utricularia is reportedly nutritious, mildly astringent, and diuretic. Preadapted to nutrient-poor, waterlogged soils, U. bifida is suitable as an alternative for small-scale herb cultivation on low pH, wet poor soils usually deemed not suitable for any crops. PMID:22619629

  3. The Interactive Effect of Multiple Stressors on Crustacean Zooplankton Communities in Montane Lakes

    Science.gov (United States)

    Brittain, Jeffrey T.; Strecker, Angela L.

    2018-02-01

    Nonnative fish introductions have altered thousands of naturally fishless montane lakes, resulting in cascading food web repercussions. Nitrogen deposition has been recognized as an anthropogenic contributor to acidification and eutrophication of freshwater ecosystems, which may affect the abundance and composition of planktonic communities. This study identified responses of zooplankton communities from two lakes (fish present versus absent) in Mount Rainier National Park to manipulations simulating an episodic disturbance of acidification and eutrophication via nitrogen addition in mesocosms. Zooplankton communities from lakes with different food web structure (i.e., fish present or absent) responded differently to the singular effects of acid and nitrogen addition. For instance, zooplankton biomass decreased in the acid treatment of the fishless lake experiment, but increased in response to acid in the fish-present experiment. In contrast, the combination of acid and nitrogen often resulted in weak responses for both lake types, resulting in nonadditive effects, i.e., the net effect of the stressors was in the opposite direction than predicted, which is known as a reversal or "ecological surprise." This experiment demonstrates the difficulty in predicting the interactive effects of multiple stressors on aquatic communities, which may pose significant challenges for habitat restoration through fish removal.

  4. Species association in tropical montane rain forest at two successional stages in Diaoluo Mountain, Hainan

    Institute of Scientific and Technical Information of China (English)

    Fude LIU; Wenjin WANG; Ming ZHANG; Jianwei ZHENG; Zhongsheng WANG; Shiting ZHANG; Wenjie YANG; Shuqing AN

    2008-01-01

    Species association is one of the basic concepts in community succession. There are different viewpoints on how species interaction changes with the progress of succession. In order to assess these relationships, we examined species associations in the tropical montane rain forest at early and late successional stages in Diaoluo Mountain, Hainan Island. Based on data from a 2 × 2 contingency table of species presence or absence, statist-ical methods including analysis of species association and χ2 tests were applied. The results show that: 1) an overall positive association was present among tree species in the communities during the two successional stages and were statistically significant at the late stage. The number of species pairs with positive and negative associations decreased throughout the process of succession, while the number with null associations was greatly increased. The same trend existed among the dominant and compan-ion species. The results indicate that the communities are developing towards a stable stage where the woody species coexist in harmony. 2) In the early-established and later invading species, all positive associations were not signifi-cant. Compared with positive and null associations, fewer negative associations were found. This implies that these species are inclined to coexist independently through por-tioning of resources. 3) Among the later invading species, positive associations were significant and no negative associations were found which suggest that these species have similar adaptive ability in the habitat and occupied overlapping niches in the community.

  5. Nutrient cycling and nutrient losses in Andean montane forests from Antioquia, Colombia

    International Nuclear Information System (INIS)

    Londono Alvarez, Adriana; Montoya Gomez, Diana Cristina; Leon Pelaez, Juan Diego; Gonzalez Hernandez, Maria Isabel

    2007-01-01

    Gravitational flow and its chemical composition were measured in montane oak forests (Quercus humboldtii), in pine (Pinus patula) and cypress (Cupressus lusitanica) plantations in Piedras Blancas, Antioquia (Colombia), over two years. Zero tension lysimeters were used at different depth soil levels, the highest gravitational flow value at highest depth (50-80 cm) was obtained in cypress plot (492-7 mm), followed by pine (14,2 mm) and oak forest (2,0 mm). A similar behavior was encountered for nutrient losses, following the same pattern as gravitational flow. thus, for oak, pine and cypress, nutrient losses were respective/y: ca: 0,004, 0,084 and 2,270 kg ha -1 Y 1 ; P 0,008, 0,052 and 1,234 kg ha -1 Y 1 , mg: 0,004, 0,022 and 0,667 kg ha -1 y 1. K losses were 0,08 and 7,092 kg ha -1 Y 1 for oak forest and cypress plantation respectively. Nutrient losses followed the next order for each type of forest: oak: K ≥ P ≥Ca≥Mg, pine: Ca≥Fe≥P>Mg≥Zn≥Mn and cypress: K≥Mn≥Ca≥P≥Fe≥Zn≥Mg

  6. Analysis of the temporal variation of the structure of a montane forest with historical of fire

    Directory of Open Access Journals (Sweden)

    Fernando Bonillo Fernandes

    2012-06-01

    Full Text Available The aim of this study was to evaluate the structural dynamic rates of an shrubs-tree component of a seasonal semideciduous upper montane forest, in Mantiqueira Mountain between 2002 and 2008. We calculated the rates of dynamic according to the number of surviving, dead individuals and recruits, as well as the rates of dynamic for gain and loss of basal area. We verified the spatial differences among the rates along the vegetation gradient parallel to ground elevation. We also studied the correlations between the rates and biotic (initial numbers of trees and initial basal area and abiotic parameters (altimetric quota. We verified that recruitment was higher than mortality, and the gain of basal area was higher than the loses. This result suggests that the forest is expanding, with gain in number of individuals and in basal area. Normally, this result characterizes forests in recuperation after some disturbance. The community sectors (basis, middle and top of hillside didn’t show any differences in terms of dynamic rates. In general, there were few significant correlations between biotic and abiotic parameters and the dynamic rates. The increase of density and basal area, the similarity of dynamic rates among the sectors and the low correlation between parameters and the dynamic of forest’s structure point out that the forest burning occurred in 90’s could be, nowadays, interfering directly in dynamic rates of forest.

  7. Commonness and Rarity: Theory and Application of a New Model to Mediterranean Montane Grasslands

    Directory of Open Access Journals (Sweden)

    José M. Rey Benayas

    1999-06-01

    Full Text Available We examined patterns of commonness and rarity among plant species in montane wet grasslands of Iberia. This examination is set within two contexts. First, we expanded on an earlier scheme for classifying species as common or rare by adding a fourth criterion, the ability of that species to occupy a larger or smaller fraction of its potential suitable habitats, i.e., habitat occupancy. Second, we explicated two theories, the superior organism theory and the generalist/specialist trade-off theory. The data consisted of 232 species distributed among 92 plots. The species were measured for mean local abundance, size of environmental volume occupied, percentage of volume occupied, range within Iberia, and range in Europe and the Mediterranean basin. In general, all measures were positively correlated, in agreement with the superior organism theory. However, specialist species were also found. Thus, patterns of commonness and rarity may be due to a combination of mechanisms. Analyses such as ours can also be used as a first step in identifying habitats and species that may be endangered.

  8. Stomatal structure and physiology do not explain differences in water use among montane eucalypts.

    Science.gov (United States)

    Gharun, Mana; Turnbull, Tarryn L; Pfautsch, Sebastian; Adams, Mark A

    2015-04-01

    Understanding the regulation of water use at the whole-tree scale is critical to advancing the utility of physiological ecology, for example in its role in predictive hydrology of forested catchments. For three eucalypt species that dominate high-elevation catchments in south-eastern Australia, we examined if whole-tree water use could be related to three widely discussed regulators of water use: stomatal anatomy, sensitivity of stomata [i.e. stomatal conductance (g(s))] to environmental influences, and sapwood area. While daily tree water use varied sixfold among species, sap velocity and sapwood area varied in parallel. Combined, stomatal structure and physiology could not explain differences in species-specific water use. Species which exhibited the fastest (Eucalyptus delegatensis) and slowest (Eucalyptus pauciflora) rates of water use both exhibited greater capacity for physiological control of g(s) [indicated by sensitivity to vapour pressure deficit (VPD)] and a reduced capacity to limit g(s) anatomically [indicated by greater potential g(s) (g(max))]. Conversely, g(s) was insensitive to VPD and g(max) was lowest for Eucalyptus radiata, the species showing intermediate rates of water use. Improved knowledge of stomatal anatomy will help us to understand the capacity of species to regulate leaf-level water loss, but seems likely to remain of limited use for explaining rates of whole-tree water use in montane eucalypts at the catchment scale.

  9. Composition of Mix Species Foraging Flocks of Birds in Riverstan of Montane Region, Sri Lanka

    Directory of Open Access Journals (Sweden)

    W.G.D.D.M. Shermila

    2013-04-01

    Full Text Available Montane zone mixed-species bird flock system is distinct from that of low-land wet zone of SriLanka, although some species are present in both systems. The present study identified the mixed speciesflocks of birds in Riverstan at Knuckles Region, Sri Lanka. Monthly transect counts and opportunisticobservations were made between January and May, 2012. A total of 78 flocks and 27 bird species wereencountered at Riverstan during the study period. The flock size varied between 2 to 13 species and 4 to58 individuals. The mean number of species per flock was 6.03 ± 2.25 and the mean number ofindividuals in a flock was 18.41±9.87. The flock size was positively correlated with the number of speciespresent (r = 0.756, P <0.05. Grey-headed Canary Flycatcher was the most abundant species (mean2.68±1.02 birds per flocks while Sri Lanka White-eye was the most frequent species (mean 5.69±3.92birds per flocks. Grey-headed Canary Flycatcher and Sri Lanka Scimitar-babbler were the nuclear speciesin Riverstan. The leading species were Sri Lanka white-eye and Sri Lanka Yellow-eared Bulbul. Differentbird species used different heights within flocks.Keywords: Mixed-species flock, Nuclear species, Abundance, Foraging flocks

  10. Air Quality Scoping Study for Ash Meadows National Wildlife Refuge, Nevada (EMSI April 2007)

    Energy Technology Data Exchange (ETDEWEB)

    Engelbrecht, Johann; Kavouras, Ilias; Campbell, Dave; Campbell, Scott; Kohl, Steven; Shafer, David

    2007-04-01

    The Desert Research Institute (DRI) is performing a scoping study as part of the U.S.Department of Energy’s Yucca Mountain Environmental Monitoring Systems Initiative (EMSI). The main objective is to obtain baseline air quality information for Yucca Mountain and an area surrounding the Nevada Test Site (NTS). Air quality and meteorological monitoring and sampling equipment housed in a mobile trailer (shelter) is collecting data at seven sites outside the NTS, including Ash Meadows National Wildlife Refuge, Sarcobatus Flat, Beatty, Rachel, Caliente, Pahranagat National Wildlife Refuge, and Crater Flat, and at four sites on the NTS. The trailer is stationed at any one site for approximately eight weeks at a time. Letter reports provide summaries of air quality and meteorological data, on completion of each site’s sampling program.

  11. Sulfur cycling and sulfide intrusion in mixed Southeast Asian tropical seagrass meadows

    DEFF Research Database (Denmark)

    Holmer, Marianne; Pedersen, Ole; Ikejima, Kou

    2006-01-01

    Seagrass distribution and sediment biogeochemical conditions were measured around Libong Island in the Andaman Sea, Thailand. Seagrass diversity was moderate for a tropical site (four species found: Cymodocea rotundata, Enhalus acoroides, Halophila ovalis and Thalassia hemprichii......), with the diminutive species H. ovalis particularly abundant and perhaps serving as important food for dugongs present in the area. Although the sediment organic matter content was low in the seagrass meadows, the sulfate reduction rates were high (48-138 mmol m-2 d-1). A significant positive relationship between...... belowground biomass and sulfate reduction rates across the seagrass species examined indicates that stimulation of microbial activity in the rhizosphere sediments is controlled by the biomass of roots and rhizomes, rather than by specific seagrass characteristics (e.g., morphology, plant activity). The low...

  12. Threatened plant species of the Nevada Test Site, Ash Meadows, central-southern Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Beatley, J.C.

    1977-04-01

    This report is a companion one to Endangered Plant Species of the Nevada Test Site, Ash Meadows, and Central-Southern Nevada (COO-2307-11) and deals with the threatened plant species of the same area. The species are those cited in the Federal Register, July 1, 1975, and include certain ones listed as occurring only in California or Arizona, but which occur also in central-southern Nevada. As with the earlier report, the purpose of this one is to record in detail the location of the past plant collections which constitute the sole or principal basis for defining the species' distributions and frequency of occurrence in southern Nye County, Nevada, and to recommend the area of the critical habitat where this is appropriate. Many of the species occur also in southern California, and for these the central-southern Nevada records are presented for consideration of the overall status of the species throughout its range.

  13. A mitochondrial DNA phylogeny of the endangered vipers of the Vipera ursinii complex

    Czech Academy of Sciences Publication Activity Database

    Gvoždík, Václav; Jandzik, D.; Cordos, B.; Řehák, I.; Kotlík, Petr

    2012-01-01

    Roč. 62, č. 3 (2012), s. 1019-1024 ISSN 1055-7903 R&D Projects: GA MŠk LC06073 Institutional research plan: CEZ:AV0Z50450515 Keywords : Conservation * Meadow viper * Phylogeny * Steppe viper * Systematics * Vipera ursinii complex Subject RIV: EH - Ecology, Behaviour Impact factor: 4.066, year: 2012

  14. EFFECTS OF A COASTAL GOLF COMPLEX ON WATER QUALITY, PERIPHYTON, AND SEAGRASS.

    Science.gov (United States)

    The objective of this study was to determine the effects of a golf course complex on water quality, colonized periphyton and seagrass meadows in adjacent freshwater, near-coastal and wetland areas. The environmental impact of the recreational facility, which uses spray wastewater...

  15. [Relation between species distribution of plant community and soil factors under grazing in alpine meadow].

    Science.gov (United States)

    Niu, Yu Jie; Yang, Si Wei; Wang, Gui Zhen; Liu, Li; Du, Guo Zhen; Hua, Li Min

    2017-12-01

    The research selected the alpine meadow located in the northeastern margin of the Qinghai-Tibet Plateau to study the changes of vegetation community and soil properties under different grazing intensities, as well as the quantitative relation between the distribution patterns of plant species and the physical and chemical properties of soil. The results showed that the grazing caused the differentiation of the initial vegetation community with the dominant plants, Elymus nutans and Stipa grandis. In the plots with high and low grazing intensities, the dominant plants had changed to Kobresia humilis and Melissitus ruthenica, and E. nutans and Poa crymophila, respectively. With the increase of grazing intensity, the plant richness, importance value and biomass were significantly decreased. The sequence of plant species importance value in each plot against grazing intensity could be fitted by a logarithmic model. The number of required plant species was reduced while the importance value of the remaining plant species accounted for 50% of the importance value in the whole vegetation community. The available P, available K, soil compaction, soil water content, stable infiltration rate and large aggregate index were significantly changed with grazing intensity, however, the changes were different. The CCA ordination showed that the soil compaction was the key factor affecting the distribution pattern of the plant species under grazing. The variance decomposition indicated that the soil factors together explained 30.5% of the distribution of the plant species, in particular the soil physical properties alone explained 22.8% of the distribution of the plant species, which had the highest rate of contribution to the plant species distribution. The soil physical properties affected the distribution pattern of plant species on grazed alpine meadow.

  16. Potential environmental effects of pack stock on meadow ecosystems of the Sierra Nevada, USA

    Science.gov (United States)

    Ostoja, Steven M.; Brooks, Matthew L.; Moore, Peggy E.; Berlow, Eric L.; Robert Blank,; Roche, Jim; Chase, Jennifer T.; Sylvia Haultain,

    2014-01-01

    Pack and saddle stock, including, but not limited to domesticated horses, mules, and burros, are used to support commercial, private and administrative activities in the Sierra Nevada. The use of pack stock has become a contentious and litigious issue for land management agencies in the region inter alia due to concerns over effects on the environment. The potential environmental effects of pack stock on Sierra Nevada meadow ecosystems are reviewed and it is concluded that the use of pack stock has the potential to influence the following: (1) water nutrient dynamics, sedimentation, temperature, and microbial pathogen content; (2) soil chemistry, nutrient cycling, soil compaction and hydrology; (3) plant individuals, populations and community dynamics, non-native invasive species, and encroachment of woody species; and (4) wildlife individuals, populations and communities. It is considered from currently available information that management objectives of pack stock should include the following: minimise bare ground, maximise plant cover, maintain species composition of native plants, minimise trampling, especially on wet soils and stream banks, and minimise direct urination and defecation by pack stock into water. However, incomplete documentation of patterns of pack stock use and limited past research limits current understanding of the effects of pack stock, especially their effects on water, soils and wildlife. To improve management of pack stock in this region, research is needed on linking measurable monitoring variables (e.g. plant cover) with environmental relevancy (e.g. soil erosion processes, wildlife habitat use), and identifying specific environmental thresholds of degradation along gradients of pack stock use in Sierra Nevada meadows.

  17. Lower Red River Meadow Restoration Project : Biennial Report 1996-97.

    Energy Technology Data Exchange (ETDEWEB)

    LRK Communications; Wildlife Habitat Institute; Pocket Water, Inc.

    2003-07-01

    The Red River has been straightened and the riparian vegetation corridor eliminated in several reaches within the watershed. The river responded by incision resulting in over-steepened banks, increased sedimentation, elevated water temperatures, depressed groundwater levels, reduced floodplain function, and degraded fish habitat. The Lower Red River Meadow Restoration Project is a multi-phase ecosystem enhancement effort that restores natural physical and biological processes and functions to stabilize the stream channel and establish high quality habitats for fish and wildlife. A natural channel restoration philosophy guides the design and on the ground activities, allowing the channel to evolve into a state of dynamic equilibrium. Two years of planning, two years of restoration in Phases I and II, and one year post-restoration monitoring are complete. By excavating new bends and reconnecting historic meanders, Phase I and II channel realignment increased channel length by 3,060 feet, decreased channel gradient by 25 percent, and increased sinuosity from 1.7 to 2.3. Cross-sectional shapes and point bars were modified to maintain deep pool habitat at low flow and to reconnect the meadow floodplain. Improved soil moisture conditions will help sustain the 31,500 native riparian plantings reestablished within these two phases. Overall, short-term restoration performance was successful. Analyses of long-term parameters document either post-restoration baseline conditions or early stages of evolution toward desired conditions. An adaptive management strategy has helped to improve restoration designs, methods, and monitoring. Lessons learned are being transferred to a variety of audiences to advance the knowledge of ecological restoration and wise management of watersheds.

  18. Sensitivity of permanent meadows areas. Preliminary report; Sensibilite des zones de prairies permanentes. Rapport preliminaire

    Energy Technology Data Exchange (ETDEWEB)

    Pourcelot, L

    2006-07-01

    The objective of this work proposed in the framework of the S.E.N.S.I.B. project on the permanent meadows areas is to compare the sensitivity of these surfaces and cheese maker sector which are associated with them, and to identify the processes which determine this sensitivity. The realization of this objective will lean on certain data of activities acquired recently by the I.R.S.N. (compartments: soils, herb, milk and cheese), as well as on new measures, on three sites: Saint-Laurent-de-Geris ( West), Beaune-Le-Froid ( center), and Massif of Jura (East). Two scales of transfers observation and sensitivity are retained. In a first time, the sensitivity of meadows areas will studied at the regional scale, from data acquired in the Massif du Jura ( between 300 and 1200 metres up). In a second time, a study will allow to compare the sensitivity of three areas retained (West, Center, East) at the national scale. The expertise will be focused on the factors of sensitivity of the transfer soil-herb and the factors of sensitivity bound to the cheese makers sectors. The data of the already available zones of study create strong variabilities of the rates of {sup 137}Cs transfer in the interfaces soil / herb and herb / milk, letting suppose that the nature of soils, the quantity and the quality of food ingested by the cattle constitutes dominating factors of sensitivity. Besides, the size of the basin of milk collection, extremely variable from a site of study in the other one, has to influence the contamination of cheeses and as such, it establishes an important factor of sensitivity of the cheese makers sector. (N.C.)

  19. Biodegradable plastic bags on the seafloor: A future threat for seagrass meadows?

    Science.gov (United States)

    Balestri, Elena; Menicagli, Virginia; Vallerini, Flavia; Lardicci, Claudio

    2017-12-15

    Marine plastic litter is a global concern. Carrier bags manufactured from non-biodegradable polymers constitute a large component of this litter. Because of their adverse impact on marine life, non-biodegradable bags have recently been replaced by biodegradable ones. However, growing evidence shows that these latter are not readily degradable in marine sediments and can alter benthic assemblages. The potential impact of biodegradable bags on seagrasses inhabiting sandy bottoms, which are the most widespread and productive ecosystems of the coastal zones, has been ignored. Mesocosm experiments were conducted to assess the effect of a commercialized biodegradable bag on a common seagrass species of the Mediterranean, Cymodocea nodosa, both at the level of individual plant (clonal growth) and of plant community (plant-plant relationships), under three culture regimes (plant alone, in combination with a neighbour of the same species or of the co-existing seagrass Zostera noltei) simulating different natural conditions (bare substrate, monospecific meadows or mixed meadows). The bag behaviour in marine sediment and sediment physical/chemical variables were also examined. After six months of sediment exposure, the bag retained considerable mass (85% initial weight) and reduced sediment pore-water oxygen concentration and pH. In the presence of bag, C. nodosa root spread and vegetative recruitment increased compared to controls, both intra- and interspecific interactions shifted from neutral to competitive, and the growth form changed from guerrilla (loosely arranged group of widely spaced ramets) to phalanx form (compact structure of closed spaced ramets) but only with Z. noltei. These findings suggest that biodegradable bags altering sediment geochemistry could promote the spatial segregation of seagrass clones and influence species coexistence. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Modeling responses of the meadow steppe dominated by Leymus chinensis to climate change

    International Nuclear Information System (INIS)

    Wang, Yuhui; Zhou, Guangsheng; Wang, Yonghe

    2007-01-01

    Grassland is one of the most widespread vegetation types worldwide and plays a significant role in regional climate and global carbon cycling. Understanding the sensitivity of Chinese grassland ecosystems to climate change and elevated atmospheric CO2 and the effect of these changes on the grassland ecosystems is a key issue in global carbon cycling. China encompasses vast grassland areas of 354 million ha of 17 major grassland types, according to a national grassland survey. In this study, a process-based terrestrial model the CENTURY model was used to simulate potential changes in net primary productivity (NPP) and soil organic carbon (SOC) of the Leymus chinensis meadow steppe (LCMS) under different scenarios of climatic change and elevated atmospheric CO2. The LCMS sensitivities, its potential responses to climate change, and the change in capacity of carbon stock and sequestration in the future are evaluated. The results showed that the LCMS NPP and SOC are sensitive to climatic change and elevated CO2. In the next 100 years, with doubled CO2 concentration, if temperature increases from 2.7-3.9C and precipitation increases by 10% NPP and SOC will increase by 7-21% and 5-6% respectively. However, if temperature increases by 7.5-7.8C and precipitation increases by only 10% NPP and SOC would decrease by 24% and 8% respectively. Therefore, changes in the NPP and SOC of the meadow steppe are attributed mainly to the amount of temperature and precipitation change and the atmospheric CO2 concentration in the future

  1. Oregon Spotted Frog (Rana pretiosa) movement and demography at Dilman Meadow: Implications for future monitoring

    Science.gov (United States)

    Chelgren, Nathan D.; Pearl, Christopher A.; Bowerman, Jay; Adams, Michael J.

    2007-01-01

    From 2001 to 2005, we studied the demography and seasonal movement of Oregon spotted frogs (Rana pretiosa) translocated into created ponds in Dilman Meadow in central Oregon. Our objectives were to inform future monitoring and management at the site, and to elucidate poorly known aspects of the species’ population ecology. Movement rates revealed complementary use of sites seasonally, with one small spring being preferred during winter that was rarely used during the rest of the year. Growth rates were significantly higher in ponds that were not used for breeding, and larger size resulted in significantly higher survival. When variation in survival by size was accounted for there was little variation among ponds in survival. Seasonal estimates of survival were lowest for males during the breeding/post-breeding redistribution period, suggesting a high cost of breeding for males. Overwintering survival for both genders was relatively high. Our study supports others in suggesting Oregon spotted frogs are specific in their overwintering habitat requirements, and that predator-free springs may be of particular value. We suggest that any future monitoring include measures of the rate of pond succession. Demographic monitoring should include metrics of both frog reproduction and survival: counts of egg masses at all ponds during spring, and capture-recapture study of survival in mid and late summer when capture rates are highest. Additional study of early life stages would be particularly useful to broaden our understanding of the species’ ecology. Specifically, adding intensive capture and marking effort after larval transformation in fall would enable a full understanding of the annual life cycle. Complete study of the annual life cycle is needed to isolate the life stages and mechanisms through which Oregon spotted frogs are affected by stressors such as nonnative predators. Dilman Meadow, which lacks many hypothesized stressors, is an important reference for

  2. Photosynthetic capacity of tropical montane tree species in relation to leaf nutrients, successional strategy and growth temperature.

    Science.gov (United States)

    Dusenge, Mirindi Eric; Wallin, Göran; Gårdesten, Johanna; Niyonzima, Felix; Adolfsson, Lisa; Nsabimana, Donat; Uddling, Johan

    2015-04-01

    Photosynthetic capacity of tree leaves is typically positively related to nutrient content and little affected by changes in growth temperature. These relationships are, however, often poorly supported for tropical trees, for which interspecific differences may be more strongly controlled by within-leaf nutrient allocation than by absolute leaf nutrient content, and little is known regarding photosynthetic acclimation to temperature. To explore the influence of leaf nutrient status, successional strategy and growth temperature on the photosynthetic capacity of tropical trees, we collected data on photosynthetic, chemical and morphological leaf traits of ten tree species in Rwanda. Seven species were studied in a forest plantation at mid-altitude (~1,700 m), whereas six species were studied in a cooler montane rainforest at higher altitude (~2,500 m). Three species were common to both sites, and, in the montane rainforest, three pioneer species and three climax species were investigated. Across species, interspecific variation in photosynthetic capacity was not related to leaf nutrient content. Instead, this variation was related to differences in within-leaf nitrogen allocation, with a tradeoff between investments into compounds related to photosynthetic capacity (higher in pioneer species) versus light-harvesting compounds (higher in climax species). Photosynthetic capacity was significantly lower at the warmer site at 1,700 m altitude. We conclude that (1) within-leaf nutrient allocation is more important than leaf nutrient content per se in controlling interspecific variation in photosynthetic capacity among tree species in tropical Rwanda, and that (2) tropical montane rainforest species exhibit decreased photosynthetic capacity when grown in a warmer environment.

  3. Fagaceae tree species allocate higher fraction of nitrogen to photosynthetic apparatus than Leguminosae in Jianfengling tropical montane rain forest, China.

    Science.gov (United States)

    Tang, Jingchao; Cheng, Ruimei; Shi, Zuomin; Xu, Gexi; Liu, Shirong; Centritto, Mauro

    2018-01-01

    Variation in photosynthetic-nitrogen use efficiency (PNUE) is generally affected by several factors such as leaf nitrogen allocation and leaf diffusional conductances to CO2, although it is still unclear which factors significantly affect PNUE in tropical montane rain forest trees. In this study, comparison of PNUE, photosynthetic capacity, leaf nitrogen allocation, and diffusional conductances to CO2 between five Fagaceae tree species and five Leguminosae tree species were analyzed in Jianfengling tropical montane rain forest, Hainan Island, China. The result showed that PNUE of Fagaceae was significantly higher than that of Leguminosae (+35.5%), attributed to lower leaf nitrogen content per area (Narea, -29.4%). The difference in nitrogen allocation was the main biochemical factor that influenced interspecific variation in PNUE of these tree species. Fagaceae species allocated a higher fraction of leaf nitrogen to the photosynthetic apparatus (PP, +43.8%), especially to Rubisco (PR, +50.0%) and bioenergetics (PB +33.3%) in comparison with Leguminosae species. Leaf mass per area (LMA) of Leguminosae species was lower than that of Fagaceae species (-15.4%). While there was no significant difference shown for mesophyll conductance (gm), Fagaceae tree species may have greater chloroplast to total leaf surface area ratios and that offset the action of thicker cell walls on gm. Furthermore, weak negative relationship between nitrogen allocation in cell walls and in Rubisco was found for Castanopsis hystrix, Cyclobalanopsis phanera and Cy. patelliformis, which might imply that nitrogen in the leaves was insufficient for both Rubisco and cell walls. In summary, our study concluded that higher PNUE might contribute to the dominance of most Fagaceae tree species in Jianfengling tropical montane rain forest.

  4. Fagaceae tree species allocate higher fraction of nitrogen to photosynthetic apparatus than Leguminosae in Jianfengling tropical montane rain forest, China

    Science.gov (United States)

    Cheng, Ruimei; Shi, Zuomin; Xu, Gexi; Liu, Shirong; Centritto, Mauro

    2018-01-01

    Variation in photosynthetic-nitrogen use efficiency (PNUE) is generally affected by several factors such as leaf nitrogen allocation and leaf diffusional conductances to CO2, although it is still unclear which factors significantly affect PNUE in tropical montane rain forest trees. In this study, comparison of PNUE, photosynthetic capacity, leaf nitrogen allocation, and diffusional conductances to CO2 between five Fagaceae tree species and five Leguminosae tree species were analyzed in Jianfengling tropical montane rain forest, Hainan Island, China. The result showed that PNUE of Fagaceae was significantly higher than that of Leguminosae (+35.5%), attributed to lower leaf nitrogen content per area (Narea, –29.4%). The difference in nitrogen allocation was the main biochemical factor that influenced interspecific variation in PNUE of these tree species. Fagaceae species allocated a higher fraction of leaf nitrogen to the photosynthetic apparatus (PP, +43.8%), especially to Rubisco (PR, +50.0%) and bioenergetics (PB +33.3%) in comparison with Leguminosae species. Leaf mass per area (LMA) of Leguminosae species was lower than that of Fagaceae species (-15.4%). While there was no significant difference shown for mesophyll conductance (gm), Fagaceae tree species may have greater chloroplast to total leaf surface area ratios and that offset the action of thicker cell walls on gm. Furthermore, weak negative relationship between nitrogen allocation in cell walls and in Rubisco was found for Castanopsis hystrix, Cyclobalanopsis phanera and Cy. patelliformis, which might imply that nitrogen in the leaves was insufficient for both Rubisco and cell walls. In summary, our study concluded that higher PNUE might contribute to the dominance of most Fagaceae tree species in Jianfengling tropical montane rain forest. PMID:29390007

  5. Temporal Activity Patterns of the Spider Wasp Pepsis montezuma Smith (Hymenoptera: Pompilidae in a Disturbed Lower Montane Rainforest (Manizales, Colombia

    Directory of Open Access Journals (Sweden)

    Carlos Restrepo-Giraldo

    2012-01-01

    Full Text Available We studied the temporal activity pattern of the spider wasp Pepsis montezuma Smith (Hymenoptera: Pompilidae in a disturbed lower montane rainforest, which is located in the city of Manizales, Colombia, at an altitude of 2,150 m. Females of this species are diurnal with two peaks of activity: one in the morning and the other in the afternoon. During the morning, nectar foraging occurred at Baccharis latifolia. During the afternoon, females hunted for tarantulas of the genus Pamphobeteus (Araneae: Theraphosidae, which were dragged backwards to the nest by the wasp. The nest was excavated before hunting. This is the first description of the behavior of Pepsis montezuma.

  6. A Simulation Model on the Competition for Light of Meadow-forming and Canopy-forming Aquatic Macrophytes at High and Low Nutrient Availability

    National Research Council Canada - National Science Library

    Best, Elly

    2004-01-01

    A simulation model has been developed that focuses on the ability of two competing submersed macrophytes, meadow-forming and canopy-forming, to maintain their biomass under different environmental conditions...

  7. The effects of burning and grazing on soil carbon dynamics in managed Peruvian tropical montane grasslands

    Directory of Open Access Journals (Sweden)

    V. Oliver

    2017-12-01

    Full Text Available Montane tropical soils are a large carbon (C reservoir, acting as both a source and a sink of CO2. Enhanced CO2 emissions originate, in large part, from the decomposition and losses of soil organic matter (SOM following anthropogenic disturbances. Therefore, quantitative knowledge of the stabilization and decomposition of SOM is necessary in order to understand, assess and predict the impact of land management in the tropics. In particular, labile SOM is an early and sensitive indicator of how SOM responds to changes in land use and management practices, which could have major implications for long-term carbon storage and rising atmospheric CO2 concentrations. The aim of this study was to investigate the impacts of grazing and fire history on soil C dynamics in the Peruvian montane grasslands, an understudied ecosystem, which covers approximately a quarter of the land area in Peru. A density fractionation method was used to quantify the labile and stable organic matter pools, along with soil CO2 flux and decomposition measurements. Grazing and burning together significantly increased soil CO2 fluxes and decomposition rates and reduced temperature as a driver. Although there was no significant effect of land use on total soil C stocks, the combination of burning and grazing decreased the proportion of C in the free light fraction (LF, especially at the lower depths (10–20 and 20–30 cm. In the control soils, 20 % of the material recovered was in the free LF, which contained 30 % of the soil C content. In comparison, the burnt–grazed soil had the smallest recovery of the free LF (10 % and a significantly lower C content (14 %. The burnt soils had a much higher proportion of C in the occluded LF (12 % compared to the not-burnt soils (7 % and there was no significant difference among the treatments in the heavy fraction (F ( ∼  70 %. The synergistic effect of burning and grazing caused changes to the soil C dynamics. CO2

  8. Hydrology and human behavior: two key factors of diarrhea incidence in montane tropical humid areas

    Science.gov (United States)

    Boithias, Laurie; Choisy, Marc; Souliyaseng, Noy; Jourdren, Marine; Quet, Fabrice; Buisson, Yves; Thammahacksa, Chanthamousone; Silvera, Norbert; Latsachack, Keooudone; Sengtaheuanghoung, Oloth; Pierret, Alain; Rochelle-Newall, Emma; Becerra, Sylvia; Ribolzi, Olivier

    2017-04-01

    The global burden of diarrhea is a leading cause of morbidity and mortality worldwide. In montane areas of South-East Asia such as northern Laos, recent changes in land use have induced increased runoff, soil erosion and in-stream suspended sediment loads, and potential pathogen dissemination. In this study we hypothesized that climate factors combined with human behavior control diarrhea incidence, either because higher rainfall, leading to higher stream discharges, suspended sediment loads and Fecal Indicator Bacteria (FIB) counts, are associated with higher numbers of reported diarrhea cases during the rainy season, or because water shortage leads to the use of less safe water sources during the dry season. For this mixed methods approach, we conducted a retrospective time series analysis of meteorological variables (rainfall, air temperature), hydrological variables (discharge, suspended sediments, FIB counts, water temperature) at the outlet of 2 catchments in Northern Lao PDR, and the number of diarrheal disease cases reported in 6 health centers located in the Luang Prabang Province. We also examined the socio-behavioral factors potentially affecting vulnerability to the effect of the climate factors, such as drinking water sources and hygiene habits. We found the FIB Escherichia coli to be present all year long (100-1,000 MPN 100 mL-1) indicating that fecal contamination is ubiquitous and constant. We found that populations switch their water supply from wells to surface water during drought periods, the latter of which appear to be at higher risk of bacterial contamination than municipal water fountains. We thus found that water shortage in the Luang Prabang area triggers diarrhea peaks during the dry and hot season and that rainfall and aquifer refill ends the epidemic during the wet season. We thus found that anthropogenic drivers, such as hygiene practices, were at least as important as environmental drivers in determining the seasonal pattern of a

  9. Transpiration of shrub species, Alnus firma under changing atmospheric environments in montane area, Japan

    Science.gov (United States)

    Miyazawa, Y.; Maruyama, A.; Inoue, A.

    2014-12-01

    In the large caldera of Mt. Aso in Japan, grasslands have been traditionally managed by the farmers. Due to changes in the social structure of the region, a large area of the grassland has been abandoned and was invaded by the shrubs with different hydrological and ecophysiological traits. Ecophysiological traits and their responses to seasonally changing environments are fundamental to project the transpiration rates under changing air and soil water environments, but less is understood. We measured the tree- and leaf-level ecophysiological traits of a shrub, Alnus firma in montane region where both rainfall and soil water content drastically changes seasonally. Sap flux reached the annual peak in evaporative summer (July-August) both in 2013 and 2014, although the duration was limited within a short period due to the prolonged rainy season before summer (2014) and rapid decrease in the air vapor pressure deficit (D) in late summer. Leaf ecophysiological traits in close relationship with gas exchange showed modest seasonal changes and the values were kept at relatively high levels typical in plants with nitrogen fixation under nutrient-poor environments. Stomatal conductance, which was measured at leaf-level measurements and sap flux measurements, showed responses to D, which coincided with the theoretical response for isohydric leaves. A multilayer model, which estimates stand-level transpiration by scaling up the leaf-level data, successfully captured the temporal trends in sap flux, suggesting that major processes were incorporated. Thus, ecophysiological traits of A. firma were characterized by the absence of responses to seasonally changing environments and the transpiration rate was the function of the interannually variable environmental conditions.

  10. Climate forcing of an emerging pathogenic fungus across a montane multi-host community.

    Science.gov (United States)

    Clare, Frances C; Halder, Julia B; Daniel, Olivia; Bielby, Jon; Semenov, Mikhail A; Jombart, Thibaut; Loyau, Adeline; Schmeller, Dirk S; Cunningham, Andrew A; Rowcliffe, Marcus; Garner, Trenton W J; Bosch, Jaime; Fisher, Matthew C

    2016-12-05

    Changes in the timings of seasonality as a result of anthropogenic climate change are predicted to occur over the coming decades. While this is expected to have widespread impacts on the dynamics of infectious disease through environmental forcing, empirical data are lacking. Here, we investigated whether seasonality, specifically the timing of spring ice-thaw, affected susceptibility to infection by the emerging pathogenic fungus Batrachochytrium dendrobatidis (Bd) across a montane community of amphibians that are suffering declines and extirpations as a consequence of this infection. We found a robust temporal association between the timing of the spring thaw and Bd infection in two host species, where we show that an early onset of spring forced high prevalences of infection. A third highly susceptible species (the midwife toad, Alytes obstetricans) maintained a high prevalence of infection independent of time of spring thaw. Our data show that perennially overwintering midwife toad larvae may act as a year-round reservoir of infection with variation in time of spring thaw determining the extent to which infection spills over into sympatric species. We used future temperature projections based on global climate models to demonstrate that the timing of spring thaw in this region will advance markedly by the 2050s, indicating that climate change will further force the severity of infection. Our findings on the effect of annual variability on multi-host infection dynamics show that the community-level impact of fungal infectious disease on biodiversity will need to be re-evaluated in the face of climate change.This article is part of the themed issue 'Tackling emerging fungal threats to animal health, food security and ecosystem resilience'. © 2016 The Authors.

  11. Prescribed-fire effects on an aquatic community of a southwest montane grassland system

    Science.gov (United States)

    Caldwell, Colleen A.; Jacobi, Gerald Z.; Anderson, Michael C.; Parmenter, Robert R.; McGann, Jeanine; Gould, William R.; DuBey, Robert; Jacobi, M. Donna

    2013-01-01

    The use of prescription fire has long been recognized as a reliable management tool to suppress vegetative succession processes and to reduce fuel loading to prevent catastrophic wildfires, but very little attention has been paid to the effects on aquatic systems. A late-fall prescribed burn was implemented to characterize effects on an aquatic community within a montane grassland system in north-central New Mexico. The fire treatment was consistent with protocols of a managed burn except that the fire was allowed to burn through the riparian area to the treatment stream to replicate natural fire behavior. In addition to summer and fall preburn assessment of the treatment and reference stream, we characterized immediate postfire effects (within a week for macroinvertebrates and within 6 months for fish) and seasonal effects over a 2-year period. Responses within the treatment stream were compared with an unburned reference stream adjacent to the prescription burn. During the burn, the diel range in air temperature increased by 5°C while diel range in water temperature did not change. Carbon–nitrogen ratios did not differ between treatment and reference streams, indicating the contribution of ash from the surrounding grassland was negligible. Although total taxa and species richness of aquatic macroinvertebrates were not altered, qualitative indices revealed departure from preburn condition due to loss of sensitive taxa (mayflies [order Ephemeroptera] and stoneflies [order Plecoptera]) and an increase in tolerant taxa (midges [order Chironomidae]) following the burn. Within 1 year of the burn, these attributes returned to preburn conditions. The density and recruitment of adult Brown Trout Salmo trutta did not differ between pre- and postburn collections, nor did fish condition differ. Fire is rarely truly replicated within a given study. Although our study represents one replication, the results will inform managers about the importance in timing (seasonality

  12. Camera trap survey of medium and large mammals in a montane rainforest of northern Peru

    Directory of Open Access Journals (Sweden)

    Carlos F. Jiménez

    2011-05-01

    Full Text Available Camera traps are a powerful tool for inventorying elusive and rare species and very useful to obtain ecologi- cal data for plans that involve wildlife conservation. In Peru, several surveys have been carried out in lowland Amazonia especially in the southeastern part of the country, but none in montane cloud forests or Yungas. We present the first camera trap studies produced in Peruvian Yungas at the locality of Querocoto village (Chota, Cajamarca, based on 2002 (dry season and 1264 (wet season camera traps-days (CTD. Two localities were surveyed in wet and dry season: The Pagaibamba Protection Forest and the San Lorenzo Forest. The wet season study was carried out in October and November, and the dry season in July to September of 2008. Eight mammalian species were recorded in both seasons. Some 66 (91.7% independent records were obtained in the dry season, but only six (8.3% in the wet one, suggesting a seasonality effect. The Mountain Paca Cunicu- lus taczanowskii was the most commonly photographed species, with 17.0 and 1.6 capture frequencies (dry and wet season respectively, whereas the Long-tailed weasel Mustela frenata (0.5 capture frequency in the dry season was the most rare species. Activity patterns suggest that Mountain Paca C. taczanowskii and the Andean Skunk C. chinga are nocturnal, while Spectacled Bear T. ornatus and Tayra E. barbara are diurnal in the study area. Our records of the Ocelot Leopardus pardalis and the Tayra E. barbara are among the highest altitudinal records known for each species. In addition, the Anta Tapirus pinchaque was also identified by its tracks, representing one of the first record known south of the Huancabamba Depression.

  13. Integrated assessment of groundwater - surface water exchange in the hillslope - riparian interface of a montane catchment

    Science.gov (United States)

    Scheliga, Bernhard; Tetzlaff, Doerthe; Nuetzmann, Gunnar; Soulsby, Chris

    2016-04-01

    Groundwater-surface water dynamics play an important role in runoff generation and the hydrologic connectivity between hillslopes and streams. Here, we present findings from a suite of integrated, empirical approaches to increase our understanding of groundwater-surface water interlinkages in a 3.2 km ^ 2 experimental catchment in the Scottish Highlands. The montane catchment is mainly underlain by granite and has extensive (70%) cover of glacial drift deposits which are up to 40 m deep and form the main aquifer in the catchment. Flat valley bottom areas fringe the stream channel and are characterised by peaty soils (0.5-4 m deep) which cover about 10% of the catchment and receive drainage from upslope areas. The transition between the hillslopes and riparian zone forms a critical interface for groundwater-surface water interactions that controls both the dynamics of riparian saturation and stream flow generation. We nested observations using wells to assess the groundwater - surface water transition, LiDAR surveys to explore the influence of micro-topography on shallow groundwater efflux and riparian wells to examine the magnitude and flux rates of deeper groundwater sources. We also used electrical resistivity surveys to assess the architecture and storage properties of drift aquifers. Finally, we used isotopic tracers to differentiate recharge sources and associated residence times as well as quantifying how groundwater dynamics affect stream flow. These new data have provided a novel conceptual framework for local groundwater - surface water exchange that is informing the development of new deterministic models for the site.

  14. Impact of Mining Activity upon Environment in Roşia Montană

    Directory of Open Access Journals (Sweden)

    SIGISMUND DUMA

    2008-01-01

    Full Text Available Roşia Montană is the greatest gold ore in Romania and one of the greatest in Europe, and its exploitation has been carried out since Antiquity up to nowadays. If the traditional extraction and processing technologies had a minimal impact upon environment, the ones adopted in modern times have affected all the components of the natural environment. In the perspective of capitalizing the gold ore through the programme elaborated by the Canadian company, Gold Corporation, the zonal geographical space will be degraded up to the level of industrial dessert over an area of 100 km2 and in case of damage, the affected area can extend enormously. The environmental problems are related both to the specific nature of such an industrial activity and, especially, to the use of enormous quantities of sodium cyanide directly on the preparation flux from the industrial plant. Few such cases are known worldwide, in several economically less developed countries. Usually, cyanides are used for treating the gold concentrations, operation done in conditions of maximum security, in closed spaces, situated in isolated zones and the neutralization (detoxification of cyanides is done in situ. The treatment of cyanides in open spaces has always generated environmental problems. Moreover, none of the cyanide treatment technologies eliminates entirely their toxic effect (less toxic chemical products are obtained. In order to avoid the production of an environmental disaster and to preserve the local patrimony values (in this place there lies the richest mining archeological site in Europe, we elaborated several recommendations we consider feasible as they allow both the capitalization of ore, which is a socio-economic necessity of the area, and the ecological reconstruction of the affected geographical space.

  15. Legal protection is not enough: Posidonia oceanica meadows in marine protected areas are not healthier than those in unprotected areas of the northwest Mediterranean Sea.

    Science.gov (United States)

    Montefalcone, Monica; Albertelli, Giancarlo; Morri, Carla; Parravicini, Valeriano; Bianchi, Carlo Nike

    2009-04-01

    Using the Conservation Index, which measures the proportional amount of dead matte relative to live Posidonia oceanica, we assessed the health of 15 P. oceanica meadows at a regional scale along the coast of Liguria (NW Mediterranean). These areas were characterized by different degrees of anthropization, from highly urbanized sites to marine protected areas. Two different scenarios were identified according to depth: in shallow zones, the health of P. oceanica meadows was related to the degree of anthropization along the coastline. In contrast, in deep zones, most meadows exhibited poor health, independent of both the degree of disturbance and the legal measures protecting the area. Working synergistically with the regional impact of increased water turbidity, local impacts from the coast were recognized as the main causes of the severe regression of most Ligurian P. oceanica meadows. We conclude that marine protected areas alone are not sufficient to guarantee the protection of P. oceanica meadows. We emphasize the need for a management network involving the Sites of Community Interest (SCIs) containing P. oceanica meadows.

  16. Cumulative impacts from multiple human activities on seagrass meadows in eastern Mediterranean waters: the case of Saronikos Gulf (Aegean Sea, Greece).

    Science.gov (United States)

    Brodersen, Maren Myrto; Pantazi, Maria; Kokkali, Athina; Panayotidis, Panayotis; Gerakaris, Vasilis; Maina, Irida; Kavadas, Stefanos; Kaberi, Helen; Vassilopoulou, Vassiliki

    2017-12-05

    Ecosystem-based management (EBM) addresses the fundamental need to account for cumulative impacts of human activities with the aim of sustainably delivering ecosystem services. The Saronikos Gulf, a large embayment of the Aegean Sea, provides a wide range of ecosystem services that are impacted by multiple human activities, deriving from the metropolitan area of Athens (situated at the northeast part of the Gulf). The anthropogenic impacts affect the status of several marine ecosystem components, e.g., seagrass meadows. Cymodocea nodosa meadows are only present at the most confined western part of the Gulf, whereas Posidonia oceanica meadows are mainly distributed in the inner and outer part of the Gulf. The aim of this study is to assess the cumulative impacts from multiple human activities on the seagrass meadows in the Gulf. The main results indicated that most impacted meadows are P. oceanica in the inner part of the Gulf, adjacent to the most urbanized coastal areas, and near port infrastructures. Land-based pollution, as well as physical damage and loss seem to be the main pressures exerted on the meadows. Understanding cumulative impacts is crucial for informing policy decisions under an EBM approach.

  17. Cultivation-dependent analysis of the microbial diversity associated with the seagrass meadows in Xincun Bay, South China Sea.

    Science.gov (United States)

    Jiang, Yu-Feng; Ling, Juan; Wang, You-Shao; Chen, Biao; Zhang, Yan-Ying; Dong, Jun-De

    2015-10-01

    Microbial communities have largely existed in the seagrass meadows. A total of 496 strains of the bacteria in the seagrass meadows, which belonged to 50 genera, were obtained by the plate cultivation method from three sites of Xincun Bay, South China Sea. The results showed that Bacillales and Vibrionales accounted for the highest proportions of organisms in all communities. The diversity of the bacteria in the sediment was higher than that associated with seagrass. Thalassia hemperichii possessed the highest abundance of bacteria, followed by Enhalus acoroides and Cymodocea rotundata. Robust seasonal dynamics in microbial community composition were also observed. It was found that microbial activities were closely tied to the growth stage of the seagrass. The microbial distribution was the lowest in site 3. The abundance of the bacteria was linked to the interactions between bacteria and plants, the condition of plant and even the coastal water quality and the nutrition level in the sediment.

  18. Post-harvest treatments in smooth-stalked meadow grass (Poa pratensis L.) - effect on carbohydrates and tiller development

    DEFF Research Database (Denmark)

    Boelt, Birte

    2007-01-01

    Temperate grass species require a period of short days/low temperature to respond to flower induction stimuli. The same environmental conditions stimulate the increase in carbohydrate concentration in aboveground biomass and the accumulation of reserve carbohydrates in the basal plant parts....... The present investigation was initiated to investigate the effect of post-harvest treatments on dry matter production in autumn, carbohydrate content, the number of reproductive tillers and seed yield in a turf-type cultivar ‘Conni' of smooth-stalked meadow grass. The results show that post-harvest treatments...... harvest and all residues removed. The results from plant samples in autumn indicate that decreasing aboveground biomass production leads to a higher carbohydrate concentration which may stimulate the reproductive development in smooth-stalked meadow grass....

  19. Are species photosynthetic characteristics good predictors of seedling post-hurricane demographic patterns and species spatiotemporal distribution in a hurricane impacted wet montane forest?

    Science.gov (United States)

    Luke, Denneko; McLaren, Kurt

    2018-05-01

    In situ measurements of leaf level photosynthetic response to light were collected from seedlings of ten tree species from a tropical montane wet forest, the John Crow Mountains, Jamaica. A model-based recursive partitioning ('mob') algorithm was then used to identify species associations based on their fitted photosynthetic response curves. Leaf area dark respiration (RD) and light saturated maximum photosynthetic (Amax) rates were also used as 'mob' partitioning variables, to identify species associations based on seedling demographic patterns (from June 2007 to May 2010) following a hurricane (Aug. 2007) and the spatiotemporal distribution patterns of stems in 2006 and 2012. RD and Amax rates ranged from 1.14 to 2.02 μmol (CO2) m-2s-1 and 2.97-5.87 μmol (CO2) m-2s-1, respectively, placing the ten species in the range of intermediate shade tolerance. Several parsimonious species 'mob' groups were formed based on 1) interspecific differences among species response curves, 2) variations in post-hurricane seedling demographic trends and 3) RD rates and species spatiotemporal distribution patterns at aspects that are more or less exposed to hurricanes. The composition of parsimonious groupings based on photosynthetic curves was not concordant with the groups based on demographic trends but was partially concordant with the RD - species spatiotemporal distribution groups. Our results indicated that the influence of photosynthetic characteristics on demographic traits and species distributions was not straightforward. Rather, there was a complex pattern of interaction between ecophysiological and demographic traits, which determined species successional status, post-hurricane response and ultimately, species distribution at our study site.

  20. Topographic and Bioclimatic Determinants of the Occurrence of Forest and Grassland in Tropical Montane Forest-Grassland Mosaics of the Western Ghats, India.

    Directory of Open Access Journals (Sweden)

    Arundhati Das

    Full Text Available The objective of this analysis was to identify topographic and bioclimatic factors that predict occurrence of forest and grassland patches within tropical montane forest-grassland mosaics. We further investigated whether interactions between topography and bioclimate are important in determining vegetation pattern, and assessed the role of spatial scale in determining the relative importance of specific topographic features. Finally, we assessed the role of elevation in determining the relative importance of diverse explanatory factors. The study area consists of the central and southern regions of the Western Ghats of Southern India, a global biodiversity hotspot. Random forests were used to assess prediction accuracy and predictor importance. Conditional inference classification trees were used to interpret predictor effects and examine potential interactions between predictors. GLMs were used to confirm predictor importance and assess the strength of interaction terms. Overall, topographic and bioclimatic predictors classified vegetation pattern with approximately 70% accuracy. Prediction accuracy was higher for grassland than forest, and for mosaics at higher elevations. Elevation was the most important predictor, with mosaics above 2000 m dominated largely by grassland. Relative topographic position measured at a local scale (within a 300 m neighbourhood was another important predictor of vegetation pattern. In high elevation mosaics, northness and concave land surface curvature were important predictors of forest occurrence. Important bioclimatic predictors were: dry quarter precipitation, annual temperature range and the interaction between the two. The results indicate complex interactions between topography and bioclimate and among topographic variables. Elevation and topography have a strong influence on vegetation pattern in these mosaics. There were marked regional differences in the roles of various topographic and bioclimatic

  1. Topographic and Bioclimatic Determinants of the Occurrence of Forest and Grassland in Tropical Montane Forest-Grassland Mosaics of the Western Ghats, India.

    Science.gov (United States)

    Das, Arundhati; Nagendra, Harini; Anand, Madhur; Bunyan, Milind

    2015-01-01

    The objective of this analysis was to identify topographic and bioclimatic factors that predict occurrence of forest and grassland patches within tropical montane forest-grassland mosaics. We further investigated whether interactions between topography and bioclimate are important in determining vegetation pattern, and assessed the role of spatial scale in determining the relative importance of specific topographic features. Finally, we assessed the role of elevation in determining the relative importance of diverse explanatory factors. The study area consists of the central and southern regions of the Western Ghats of Southern India, a global biodiversity hotspot. Random forests were used to assess prediction accuracy and predictor importance. Conditional inference classification trees were used to interpret predictor effects and examine potential interactions between predictors. GLMs were used to confirm predictor importance and assess the strength of interaction terms. Overall, topographic and bioclimatic predictors classified vegetation pattern with approximately 70% accuracy. Prediction accuracy was higher for grassland than forest, and for mosaics at higher elevations. Elevation was the most important predictor, with mosaics above 2000 m dominated largely by grassland. Relative topographic position measured at a local scale (within a 300 m neighbourhood) was another important predictor of vegetation pattern. In high elevation mosaics, northness and concave land surface curvature were important predictors of forest occurrence. Important bioclimatic predictors were: dry quarter precipitation, annual temperature range and the interaction between the two. The results indicate complex interactions between topography and bioclimate and among topographic variables. Elevation and topography have a strong influence on vegetation pattern in these mosaics. There were marked regional differences in the roles of various topographic and bioclimatic predictors across the

  2. Accumulation of selenium and assessment of the microelements contents in rape spring on meadow-black soil

    International Nuclear Information System (INIS)

    Ermokhin, Yu.I.; Sindireva, A.V.

    2008-01-01

    Quantitative correlation was installed as a result of work between arrival of the selenium on meadow-black soil and contents of this element in green mass of the rape spring. Correlation between the contents of Se and Cd, Ni, Zn in green mass at the rape spring was studied. In this article the assessment of the microelements contents depending on doses and methods of using selenium is offered

  3. Geochip-based analysis of microbial communities in alpine meadow soils in the Qinghai-Tibetan plateau.

    Science.gov (United States)

    Zhang, Yuguang; Lu, Zhenmei; Liu, Shanshan; Yang, Yunfeng; He, Zhili; Ren, Zuohua; Zhou, Jizhong; Li, Diqiang

    2013-03-29

    GeoChip 3.0, a microbial functional gene array, containing ~28,000 oligonucleotide probes and targeting ~57,000 sequences from 292 functional gene families, provided a powerful tool for researching microbial community structure in natural environments. The alpine meadow is a dominant plant community in the Qinghai-Tibetan plateau, hence it is important to profile the unique geographical flora and assess the response of the microbial communities to environmental variables. In this study, Geochip 3.0 was employed to understand the microbial functional gene diversity and structure, and metabolic potential and the major environmental factors in shaping microbial communities structure of alpine meadow soil in Qinghai-Tibetan Plateau. A total of 6143 microbial functional genes involved in carbon degradation, carbon fixation, methane oxidation and production, nitrogen cycling, phosphorus utilization, sulphur cycling, organic remediation, metal resistance, energy process and other category were detected in six soil samples and high diversity was observed. Interestingly, most of the detected genes associated with carbon degradation were derived from cultivated organisms. To identify major environmental factors in shaping microbial communities, Mantel test and CCA Statistical analyses were performed. The results indicated that altitude, C/N, pH and soil organic carbon were significantly (P the microbial functional structure and a total of 80.97% of the variation was significantly explained by altitude, C/N and pH. The C/N contributed 38.2% to microbial functional gene variation, which is in accordance with the hierarchical clustering of overall microbial functional genes. High overall functional genes and phylogenetic diversity of the alpine meadow soil microbial communities existed in the Qinghai-Tibetan Plateau. Most of the genes involved in carbon degradation were derived from characterized microbial groups. Microbial composition and structures variation were

  4. Rapid upslope shifts in New Guinean birds illustrate strong distributional responses of tropical montane species to global warming

    Science.gov (United States)

    Freeman, Benjamin G.; Class Freeman, Alexandra M.

    2014-01-01

    Temperate-zone species have responded to warming temperatures by shifting their distributions poleward and upslope. Thermal tolerance data suggests that tropical species may respond to warming temperatures even more strongly than temperate-zone species, but this prediction has yet to be tested. We addressed this data gap by conducting resurveys to measure distributional responses to temperature increases in the elevational limits of the avifaunas of two geographically and faunally independent New Guinean mountains, Mt. Karimui and Karkar Island, 47 and 44 y after they were originally surveyed. Although species richness is roughly five times greater on mainland Mt. Karimui than oceanic Karkar Island, distributional shifts at both sites were similar: upslope shifts averaged 113 m (Mt. Karimui) and 152 m (Karkar Island) for upper limits and 95 m (Mt. Karimui) and 123 m (Karkar Island) for lower limits. We incorporated these results into a metaanalysis to compare distributional responses of tropical species with those of temperate-zone species, finding that average upslope shifts in tropical montane species match local temperature increases significantly more closely than in temperate-zone montane species. That tropical species appear to be strong responders has global conservation implications and provides empirical support to hitherto untested models that predict widespread extinctions in upper-elevation tropical endemics with small ranges. PMID:24550460

  5. Ranging behavior of eastern hoolock gibbon (Hoolock leuconedys) in a northern montane forest in Gaoligongshan, Yunnan, China.

    Science.gov (United States)

    Zhang, Dao; Fei, Han-Lan; Yuan, Sheng-Dong; Sun, Wen-Mo; Ni, Qing-Yong; Cui, Liang-Wei; Fan, Peng-Fei

    2014-04-01

    Generally, food abundance and distribution exert important influence on primate ranging behavior. Hoolock gibbons (genus Hoolock) live in lowland and montane forests in India, Bangladesh, Myanmar and China. All information about hoolock gibbons comes from studies on western hoolock gibbons (Hoolock hoolock) living in lowland forest. Between August 2010 and September 2011, we studied the ranging behavior of one habituated group of eastern hoolock gibbon (H. leuconedys) living in a seasonal montane forest in Gaoligongshan, Yunnan, China. Results show that the study group did not increase foraging effort, calculated in this study as the daily path length, when fruit was less available. Instead, the gibbons fed more on leaves and decreased traveling to conserve energy. They relied heavily on a single food species in most study months which was patchily distributed within their total (14-month) home range, and during most months they used only a small portion of their total home range. In order to find enough food, the group shifted its monthly home range according to the seasonal availability of food species. To satisfy their annual food requirements, they occupied a total home range of 93 ha. The absence of neighboring groups of gibbons and the presence of tsaoko cardamom (Amomum tsaoko) plantations may also have influenced the ranging behavior of the group. Further long-term studies of neighboring groups living in intact forests are required to assess these effects.

  6. Deposition of mercury in forests across a montane elevation gradient: Elevational and seasonal patterns in methylmercury inputs and production

    Science.gov (United States)

    Gerson, Jacqueline R.; Driscoll, Charles T.; Demers, Jason D.; Sauer, Amy K.; Blackwell, Bradley D.; Montesdeoca, Mario R.; Shanley, James B.; Ross, Donald S.

    2017-08-01

    Global mercury contamination largely results from direct primary atmospheric and secondary legacy emissions, which can be deposited to ecosystems, converted to methylmercury, and bioaccumulated along food chains. We examined organic horizon soil samples collected across an elevational gradient on Whiteface Mountain in the Adirondack region of New York State, USA to determine spatial patterns in methylmercury concentrations across a forested montane landscape. We found that soil methylmercury concentrations were highest in the midelevation coniferous zone (0.39 ± 0.07 ng/g) compared to the higher elevation alpine zone (0.28 ± 0.04 ng/g) and particularly the lower elevation deciduous zone (0.17 ± 0.02 ng/g), while the percent of total mercury as methylmercury in soils decreased with elevation. We also found a seasonal pattern in soil methylmercury concentrations, with peak methylmercury values occurring in July. Given elevational patterns in temperature and bioavailable total mercury (derived from mineralization of soil organic matter), soil methylmercury concentrations appear to be driven by soil processing of ionic Hg, as opposed to atmospheric deposition of methylmercury. These methylmercury results are consistent with spatial patterns of mercury concentrations in songbird species observed from other studies, suggesting that future declines in mercury emissions could be important for reducing exposure of mercury to montane avian species.

  7. Comparison of carbon uptake estimates from forest inventory and Eddy-Covariance for a montane rainforest in central Sulawesi

    Science.gov (United States)

    Heimsch, Florian; Kreilein, Heiner; Rauf, Abdul; Knohl, Alexander

    2016-04-01

    Rainforests in general and montane rainforests in particular have rarely been studied over longer time periods. We aim to provide baseline information of a montane tropical forest's carbon uptake over time in order to quantify possible losses through land-use change. Thus we conducted a re-inventory of 22 10-year old forest inventory plots, giving us a rare opportunity to quantify carbon uptake over such a long time period by traditional methods. We discuss shortfalls of such techniques and why our estimate of 1.5 Mg/ha/a should be considered as the lower boundary and not the mean carbon uptake per year. At the same location as the inventory, CO2 fluxes were measured with the Eddy-Covariance technique. Measurements were conducted at 48m height with an LI 7500 open-path infrared gas analyser. We will compare carbon uptake estimates from these measurements to those of the more conventional inventory method and discuss, which factors are probably responsible for differences.

  8. Deposition of mercury in forests across a montane elevation gradient: Elevational and seasonal patterns in methylmercury inputs and production

    Science.gov (United States)

    Gerson, Jacqueline R.; Driscoll, Charles T.; Demers, Jason D.; Sauer, Amy K.; Blackwell, Bradley D.; Montesdeoca, Mario R.; Shanley, James B.; Ross, Donald S.

    2017-01-01

    Global mercury contamination largely results from direct primary atmospheric and secondary legacy emissions, which can be deposited to ecosystems, converted to methylmercury, and bioaccumulated along food chains. We examined organic horizon soil samples collected across an elevational gradient on Whiteface Mountain in the Adirondack region of New York State, USA to determine spatial patterns in methylmercury concentrations across a forested montane landscape. We found that soil methylmercury concentrations were highest in the midelevation coniferous zone (0.39 ± 0.07 ng/g) compared to the higher elevation alpine zone (0.28 ± 0.04 ng/g) and particularly the lower elevation deciduous zone (0.17 ± 0.02 ng/g), while the percent of total mercury as methylmercury in soils decreased with elevation. We also found a seasonal pattern in soil methylmercury concentrations, with peak methylmercury values occurring in July. Given elevational patterns in temperature and bioavailable total mercury (derived from mineralization of soil organic matter), soil methylmercury concentrations appear to be driven by soil processing of ionic Hg, as opposed to atmospheric deposition of methylmercury. These methylmercury results are consistent with spatial patterns of mercury concentrations in songbird species observed from other studies, suggesting that future declines in mercury emissions could be important for reducing exposure of mercury to montane avian species.

  9. Response of epiphytic bryophytes to simulated N deposition in a subtropical montane cloud forest in southwestern China.

    Science.gov (United States)

    Song, Liang; Liu, Wen-Yao; Ma, Wen-Zhang; Qi, Jin-Hua

    2012-11-01

    A field manipulation experiment was conducted in a subtropical montane cloud forest in southwestern China to determine the possible responses of epiphytic bryophytes to increasing nitrogen (N) deposition from community to physiology level, and to find sensitive epiphytic bryophytes that may be used as indicators for assessing the degree of N pollution. N addition had significantly negative effects on species richness and cover of the epiphytic bryophyte community. Harmful effects of high N loads were recorded for chlorophyll, growth, and vitality of the species tested. The decline of some epiphytic bryophytes may result from detrimental effects on degradation to photosynthetic pigments. Bazzania himalayana (Mitt.) Schiffn., Bazzania ovistipula (Steph.) Mizut., and Homaliodendron flabellatum (Sm.) Fleisch. are candidates in atmospheric nitrogen monitoring. Epiphytic bryophytes in the montane cloud forest are very sensitive to increasing N deposition and often difficult to recover once they have been destroyed, providing early detection of enhanced N pollution for trees or even the whole forest ecosystem. The inference that increasing N pollution may lead to loss of biodiversity is a concern to the developing economy in western China, and should alert the government to the adverse impacts caused by increased industrial pollution during the process of China's West Development.

  10. Gold and Displacement in Eastern Europe: Risks and Uncertainty at Roşia Montană

    Directory of Open Access Journals (Sweden)

    FILIP ALEXANDRESCU

    2011-01-01

    Full Text Available The Canadian-Romanian gold mining project at Roşia Montanǎ in Romania is known as the largest opencast gold mine being planned now in Europe. It involves the displacement of several thousand inhabitants, mostly former gold miners and a smaller number of farmers. The land and houses of more than three quarters of this population have already been acquired by the project owners, although the project has not yet received its formal environmental clearance. The paper analyzes the risks facing the displaced population of Roşia Montană, employing as analytical methodology the Impoverishment Risks and Reconstruction (IRR model, developed by Michael M. Cernea. The paper argues for an expansion of the IRR model. By taking into account the macro (extralocal forces that shape displacement and paying closer attention to the micro (subjective experience of this process, it becomes possible to understand the effects of uncertainty and vulnerability in displacement. The author's participant observations and in-depth interviews with local families are complemented with secondary analyses of data from several other socio-economic surveys and with the analysis of the Resettlement and Relocation Action Plan of the project owners.

  11. Species diversity, vegetation pattern and conservation of Gentiana macrophylla Pall. communities in Dongling mountain meadow, Beijing, China

    International Nuclear Information System (INIS)

    Sadia, S.; Zhang, J.T.; Bai, X.; Shedayi, A.A.; Tariq, A.

    2017-01-01

    Gentiana macrophylla, native to mountainous areas of Central and Southern Asia, is most popular remedy for rheumatism and pains in Traditional Chinese Medicine with an extensive demand in local market. Our study aimed to classify G. macrophylla communities and to find out the impact of topographic and soil factors on their diversity and distribution in Dongling mountain meadow, Beijing, China. Seventy five samples in 15 transects separated by 50m distance in altitude along an elevation gradient (1592-2298m) were established by quadrate method. TWINSAPN and CCA were used for classification and ordination, respectively. Six diversity indices (Species richness, Shannon-Weiner heterogeneity, Simpson’s index, Hill’s index, Pielou evenness and McIntosh evenness) were used to analyze the pattern of species diversity and polynomial regression analysis was used to establish their relationship with environmental variables. TWINSPAN classified G. macrophylla communities into 8 types and CCA indicated that soil pH, soil temperature, soil type, disturbance, total N, total K, Mg and Zn were significantly related to these communities. Elevation was the most significant factor that affecting the diversity and distribution of G. macrophylla communities. Significant effect of environment, topography and disturbance to meadow communities of G. macrophylla highly suggests some important measures such as uprooting restriction, tourism limitation in meadow area, monitoring of functional diversity, fertilization, irrigation, cloning and cultivation to protect and conserve it and its communities to be used in medicine industry. (author)

  12. Physiognomy and distribution of mountain meadows in an alpine valley over 150 years of spontaneous forest expansion

    Directory of Open Access Journals (Sweden)

    Sitzia T

    2012-02-01

    Full Text Available Through the classification of current and historical aerial photosbetween 1973 and 2006, we analysed the evolution of size, shape and connectivity of 59 mountain meadows (maggenghi of the Pejo district (Trentino, Northern Italy. The maggenghi are scattered patches within a forested matrix. We conducted the same analysis on an Austro-Hungarian cadastral map of 1859. The total surface covered by maggenghi was 137.4 ha in 1973, and decreased to 78.3 ha (57% in 2006. The mean shape and connectivity index in 1973 are significantly lower than those of 2006. Within a 1-km radius around the studied patches, woodlands increased by 7% in the same time range. Among the 25 maggenghi present in 1958, 12 has been subdivided into 39 smaller fragments and 13 has been reduced in their size without any fragmentation. A general process of meadow patches evolution which included area and connectivity reduction and shape simplification has been noticed. This process is common to many other alpine landscapes. The study of these processes is fundamental for policies aimed to conservation of mountain meadows, as well as to identify the single patches deserving conservation for their current and historical landscape structure, as many studies report their significant effects on local floristic diversity.

  13. In-situ injection of potassium hydroxide into briquetted wheat straw and meadow grass - Effect on biomethane production.

    Science.gov (United States)

    Feng, Lu; Moset, Veronica; Li, Wanwu; Chen, Chang; Møller, Henrik Bjarne

    2017-09-01

    Alkaline pretreatment of lignocellulosic biomass has been intensively investigated but heavy water usage and environmental pollution from wastewater limits its industrial application. This study presents a pretreatment technique by in-situ injection of potassium hydroxide concentrations ranging from 0.8% to 10% (w/w) into the briquetting process of wheat straw and meadow grass. Results show that the biomethane yield and hydrolysis rate was improved significantly with a higher impact on wheat straw compared to meadow grass. The highest biomethane yield from wheat straw briquettes of 353mL.g -1 VS was obtained with 6.27% (w/w) potassium hydroxide injection, which was 14% higher than from untreated wheat straw. The hydrolysis rates of wheat straw and meadow grass increased from 4.27×10 -2 to 5.32×10 -2 d -1 and 4.19×10 -2 to 6.00×10 -2 d -1 , respectively. The low water usage and no wastewater production make this a promising technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Butterfly Density and Behaviour in Uncut Hay Meadow Strips: Behavioural Ecological Consequences of an Agri-Environmental Scheme

    Science.gov (United States)

    Lebeau, Julie; Wesselingh, Renate A.; Van Dyck, Hans

    2015-01-01

    Sparing zones from mowing has been proposed, and applied, to improve local conditions for survival and reproduction of insects in hay meadows. However, little is known about the efficiency of refuge zones and the consequences for local populations. We studied population densities of butterflies before and after mowing in the refuge zone of 15 meadows in 2009 and 2011. We also studied the behaviour of the meadow brown (Maniola jurtina) comparing nectar use, interactions and flights in the refuge zone before and after mowing. Densities of grassland butterflies in this zone doubled on average after mowing. The density of females of M. jurtina increased on average fourfold, while males showed a more modest increase. In line with the idea of increased scramble competition in the refuge zone after mowing, M. jurtina increased the time spent on nectar feeding, the preferred nectar source was visited more frequently, and females made more use of non-preferred nectar sources. Maniola jurtina did not interact more with conspecifics after mowing, but interactions lasted longer. Flight tracks did not change in linearity, but were faster and shorter after mowing. After mowing, only a part of the local grassland butterflies moved to the uncut refuge zone. The resulting concentration effect alters the time allocated to different activities, nectar use and movements. These aspects have been largely ignored for agri-environmental schemes and grassland management in nature reserves and raise questions about optimal quantities and quality of uncut refuge sites for efficient conservation of grassland arthropods in agricultural landscapes. PMID:26284618

  15. Effect of Polonite used for phosphorus removal from wastewater on soil properties and fertility of a mountain meadow

    International Nuclear Information System (INIS)

    Cucarella, Victor; Mazurek, Ryszard; Zaleski, Tomasz; Kopec, Michal; Renman, Gunno

    2009-01-01

    Reactive filter materials used for phosphorus (P) removal from wastewater can be disposed of as soil amendments after treatment, thus recycling P and other macro- and micro-nutrients to plants. In addition, materials with a high pH and Ca content, such as Polonite, are potential soil conditioners, which can be particularly beneficial for acid soils. Polonite previously used for on-site wastewater treatment was applied as a soil amendment to a mountain meadow. The amendment significantly increased soil pH and decreased the hydrolytic acidity, thus reducing Al toxicity risks. The effects were comparable to those of liming. No difference in yield and P uptake by meadow plants was observed. The uptake of metals was lower for amended soils, especially the uptake of Mn. Using Polonite after wastewater treatment as a soil amendment is thus a viable disposal alternative that can replace liming, when necessary, being capable of recycling P and other nutrients to meadow plants. - Filter substrate Polonite can benefit acid soils after wastewater treatment.

  16. Responses of plant community composition and biomass production to warming and nitrogen deposition in a temperate meadow ecosystem.

    Science.gov (United States)

    Zhang, Tao; Guo, Rui; Gao, Song; Guo, Jixun; Sun, Wei

    2015-01-01

    Climate change has profound influences on plant community composition and ecosystem functions. However, its effects on plant community composition and biomass production are not well understood. A four-year field experiment was conducted to examine the effects of warming, nitrogen (N) addition, and their interactions on plant community composition and biomass production in a temperate meadow ecosystem in northeast China. Experimental warming had no significant effect on plant species richness, evenness, and diversity, while N addition highly reduced the species richness and diversity. Warming tended to reduce the importance value of graminoid species but increased the value of forbs, while N addition had the opposite effect. Warming tended to increase the belowground biomass, but had an opposite tendency to decrease the aboveground biomass. The influences of warming on aboveground production were dependent upon precipitation. Experimental warming had little effect on aboveground biomass in the years with higher precipitation, but significantly suppressed aboveground biomass in dry years. Our results suggest that warming had indirect effects on plant production via its effect on the water availability. Nitrogen addition significantly increased above- and below-ground production, suggesting that N is one of the most important limiting factors determining plant productivity in the studied meadow steppe. Significant interactive effects of warming plus N addition on belowground biomass were also detected. Our observations revealed that environmental changes (warming and N deposition) play significant roles in regulating plant community composition and biomass production in temperate meadow steppe ecosystem in northeast China.

  17. Does the different mowing regime affect soil biological activity and floristic composition of thermophilous Pieniny meadow?

    Science.gov (United States)

    Józefowska, Agnieszka; Zaleski, Tomasz; Zarzycki, Jan

    2016-04-01

    The study area was located in the Pieniny National Park in the Carpathian Mountain (Southern Poland). About 30% of Park's area is covered by meadows. The climax stage of this area is forest. Therefore extensive use is indispensable action to keep semi-natural grassland such as termophilous Pieniny meadows, which are characterized by a very high biodiversity. The purpose of this research was to answer the question, how the different way of mowing: traditional scything (H), and mechanical mowing (M) or abandonment of mowing (N) effect on the biological activity of soil. Soil biological activity has been expressed by microbial and soil fauna activity. Microbial activity was described directly by count of microorganisms and indirectly by enzymatic activity (dehydrogenase - DHA) and the microbial biomass carbon content (MBC). Enchytraeidae and Lumbricidae were chosen as representatives of soil fauna. Density and species diversity of this Oligochaeta was determined. Samples were collected twice in June (before mowing) and in September (after mowing). Basic soil properties, such as pH value, organic carbon and nitrogen content, moisture and temperature, were determined. Mean count of vegetative bacteria forms, fungi and Actinobacteria was higher in H than M and N. Amount of bacteria connected with nitrification and denitrification process and Clostridium pasteurianum was the highest in soil where mowing was discontinued 11 years ago. The microbial activity measured indirectly by MBC and DHA indicated that the M had the highest activity. The soil biological activity in second term of sampling had generally higher activity than soil collected in June. That was probably connected with highest organic carbon content in soil resulting from mowing and the end of growing season. Higher earthworm density was in mowing soil (220 and 208 individuals m-2 in H and M respectively) compare to non-mowing one (77 ind. m-2). The density of Enchytraeidae was inversely, the higher density

  18. Evaluation of Above Ground Biomass Estimation Accuracy for Alpine Meadow Based on MODIS Vegetation Indices

    Directory of Open Access Journals (Sweden)

    Meng Bao-Ping

    2017-01-01

    Full Text Available Animal husbandry is the main agricultural type over the Tibetan Plateau, above ground biomass (AGB is very important to monitor the productivity for administration of grassland resources and grazing balance. The MODIS vegetation indices have been successfully used in numerous studies on grassland AGB estimation in the Tibetan Plateau area. However, there are considerable differences of AGB estimation models both in the form of the models and the accuracy of estimation. In this study, field measurements of AGB data at Sangke Town, Gansu Province, China in four years (2013-2016 and MODIS indices (NDVI and EVI are combined to construct AGB estimation models of alpine meadow grassland. The field measured AGB are also used to evaluate feasibility of models developed for large scale in applying to small area. The results show that (1 the differences in biomass were relatively large among the 5 sample areas of alpine meadow grassland in the study area during 2013-2016, with the maximum and minimum biomass values of 3,963 kg DW/ha and 745.5 kg DW/ha, respectively, and mean value of 1,907.7 kg DW/ha; the mean of EVI value range (0.42-0.60 are slightly smaller than the NDVI’s (0.59-0.75; (2 the optimum estimation model of grassland AGB in the study area is the exponential model based on MODIS EVI, with root mean square error of 656.6 kg DW/ha and relative estimation errors (REE of 36.3%; (3 the estimation errors of grassland AGB models previously constructed at different spatial scales (the Tibetan Plateau, the Gannan Prefecture, and Xiahe County are higher than those directly constructed based on the small area of this study by 9.5%–31.7%, with the increase of the modeling study area scales, the REE increasing as well. This study presents an improved monitoring algorithm of alpine natural grassland AGB estimation and provides a clear direction for future improvement of the grassland AGB estimation and grassland productivity from remote sensing

  19. Prevalence of Babesia canis, Borrelia burgdorferi sensu lato, and Anaplasma phagocytophilum in hard ticks collected from meadows of Lubelskie Voivodship (eastern Poland

    Directory of Open Access Journals (Sweden)

    Dzięgiel Beata

    2014-03-01

    Full Text Available The aim of the study was to assess the distribution of Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato, and Babesia canis in adult females and males of Ixodes ricinus and Dermacentor reticulatus ticks, inhabiting meadows near large forest complexes throughout the Lubelskie Voivodship (eastern region of Poland. Ticks were collected using the flagging method. Among 720 ticks collected, 506 were identified as D. reticulatus, and 214 as I. ricinus. DNA of B. canis and B. burgdorferi s.l. was detected in 21.3% and 0.6% of D. reticulatus ticks, respectively. In I. ricinus ticks, DNA specific to B. burgdorferi s.l. and A. phagocytophilum was detected in 5.6% and 10.3%, respectively. Co-infections of B. burgdorferi s.l. and A. phagocytophilum were found in two I. ricinus ticks. These results indicate that the Lublin region is an area at risk of tick-borne diseases of humans and animals, which must be considered in clinical practice.

  20. Flea abundance, diversity, and plague in Gunnison's prairie dogs (Cynomys gunnisoni) and their burrows in montane grasslands in northern New Mexico

    Science.gov (United States)

    Megan M. Friggens; Robert R. Parmenter; Michael Boyden; Paulette L. Ford; Kenneth Gage; Paul Keim

    2010-01-01

    Plague, a flea-transmitted infectious disease caused by the bacterium Yersinia pestis, is a primary threat to the persistence of prairie dog populations (Cynomys spp.). We conducted a 3-yr survey (2004-2006) of fleas from Gunnison's prairie dogs (Cynomys gunnisoni) and their burrows in montane grasslands in Valles Caldera National Preserve in New Mexico. Our...

  1. A comparison of point counts with a new acoustic sampling method: a case study of a bird community from the montane forests of Mount Cameroon

    Czech Academy of Sciences Publication Activity Database

    Sedláček, O.; Vokurková, J.; Ferenc, M.; Djomo Nana, E.; Albrecht, Tomáš; Hořák, D.

    2015-01-01

    Roč. 86, č. 3 (2015), s. 213-220 ISSN 0030-6525 R&D Projects: GA ČR(CZ) GAP505/11/1617 Institutional support: RVO:68081766 Keywords : abundance * automatic recording units * montane forest * point count * species richness * species turnover Subject RIV: EG - Zoology Impact factor: 0.418, year: 2015

  2. Influence of prevailing disturbances on soil biology and biochemistry of montane habitats at Nanda Devi Biosphere Reserve, India during wet and dry seasons

    DEFF Research Database (Denmark)

    Singh, S.K.; Singh, Anoop; Rai, J.P.N.

    2011-01-01

    The impact of prevailing disturbances in montane habitats of Nanda Devi Biosphere Reserve (NDBR) was studied on soil microbial population, biomass, soil respiration and enzyme activities during wet and dry seasons. The physico-chemical characteristics of soils exhibited conspicuous variation in t...

  3. Highly diverse molluscan assemblages of Posidonia oceanica meadows in northwestern Alboran Sea (W Mediterranean): Seasonal dynamics and environmental drivers

    Science.gov (United States)

    Urra, Javier; Mateo Ramírez, Ángel; Marina, Pablo; Salas, Carmen; Gofas, Serge; Rueda, José L.

    2013-01-01

    The seasonal dynamics of the molluscan fauna associated with the westernmost populations of the Mediterranean seagrass Posidonia oceanica, has been studied throughout an annual cycle in the northwestern coasts of the Alboran Sea. Samples were collected seasonally (5 replicated per season) using a non-destructive sampling technique (airlift sampler) on quadrats of 50 × 50 cm at 2 sites located 7 km apart. Several environmental variables from the water column (temperature, chlorophyll a), the sediment (percentage of organic matter) and the seagrass meadows (shoot density, leaf height and width, number of leaves per shoot) were also measured in order to elucidate their relationships with the dynamics of the molluscan assemblages. In these meadows, a total of 17,416 individuals of molluscs were collected, belonging to 71 families and 171 species, being Rissoidae, Pyramidellidae and Trochidae the best-represented families, and Mytilidae, Nassaridae and Trochidae the dominant ones in terms of abundance. The assemblages were dominated by micro-algal grazers, filter feeders and ectoparasites (including those feeding on sessile preys). The species richness and the abundance displayed significant maximum values in summer, whereas evenness and diversity displayed maximum values in spring, being significant for the evenness. Both abundance and species richness values were positively correlated to seawater temperature and percentage organic matter, only for the latter, and negatively to leaf width. Significant seasonal groupings were obtained with multivariate analyses (MDS, Cluster, ANOSIM) using qualitative and quantitative data that could be mainly related to biological aspects (i.e. recruitment) of single species. The molluscan assemblages are influenced by the biogeographical location of the area (Alboran Sea), reflected in the absence or scarcity of most Mediterranean species strictly associated with P. oceanica (e.g. Tricolia speciosa, Rissoa ventricosa) and by the

  4. Dataset of Phenology of Mediterranean high-mountain meadows flora (Sierra Nevada, Spain)

    Science.gov (United States)

    Pérez-Luque, Antonio Jesús; Sánchez-Rojas, Cristina Patricia; Zamora, Regino; Pérez-Pérez, Ramón; Bonet, Francisco Javier

    2015-01-01

    Abstract Sierra Nevada mountain range (southern Spain) hosts a high number of endemic plant species, being one of the most important biodiversity hotspots in the Mediterranean basin. The high-mountain meadow ecosystems (borreguiles) harbour a large number of endemic and threatened plant species. In this data paper, we describe a dataset of the flora inhabiting this threatened ecosystem in this Mediterranean mountain. The dataset includes occurrence data for flora collected in those ecosystems in two periods: 1988–1990 and 2009–2013. A total of 11002 records of occurrences belonging to 19 orders, 28 families 52 genera were collected. 73 taxa were recorded with 29 threatened taxa. We also included data of cover-abundance and phenology attributes for the records. The dataset is included in the Sierra Nevada Global-Change Observatory (OBSNEV), a long-term research project designed to compile socio-ecological information on the major ecosystem types in order to identify the impacts of global change in this area. PMID:25878552

  5. Light availability and temperature, not increased CO2, will structure future meadows of Posidonia oceanica

    KAUST Repository

    Hendriks, Iris E.

    2017-02-15

    We evaluated the photosynthetic performance of Posidonia oceanica during short-term laboratory exposures to ambient and elevated temperatures (24–25°C and 29–30°C) warming and pCO2 (380, 750 and 1000ppm pCO2) under normal and low light conditions (200 and 40μmol photons m−2s−1 respectively). Plant growth was measured at the low light regime and showed a negative response to warming. Light was a critical factor for photosynthetic performance, although we found no evidence of compensation of photosynthetic quantum efficiency in high light. Relative Electron Rate Transport (rETRmax) was higher in plants incubated in high light, but not affected by pCO2 or temperature. The saturation irradiance (Ik) was negatively affected by temperature. We conclude that elevated CO2 does not enhance photosynthetic activity and growth, in the short term for P. oceanica, while temperature has a direct negative effect on growth. Low light availability also negatively affected photosynthetic performance during the short experimental period examined here. Therefore increasing concentrations of CO2 may not compensate for predicted future conditions of warmer water and higher turbidity for seagrass meadows.

  6. Dataset of Phenology of Mediterranean high-mountain meadows flora (Sierra Nevada, Spain).

    Science.gov (United States)

    Pérez-Luque, Antonio Jesús; Sánchez-Rojas, Cristina Patricia; Zamora, Regino; Pérez-Pérez, Ramón; Bonet, Francisco Javier

    2015-01-01

    Sierra Nevada mountain range (southern Spain) hosts a high number of endemic plant species, being one of the most important biodiversity hotspots in the Mediterranean basin. The high-mountain meadow ecosystems (borreguiles) harbour a large number of endemic and threatened plant species. In this data paper, we describe a dataset of the flora inhabiting this threatened ecosystem in this Mediterranean mountain. The dataset includes occurrence data for flora collected in those ecosystems in two periods: 1988-1990 and 2009-2013. A total of 11002 records of occurrences belonging to 19 orders, 28 families 52 genera were collected. 73 taxa were recorded with 29 threatened taxa. We also included data of cover-abundance and phenology attributes for the records. The dataset is included in the Sierra Nevada Global-Change Observatory (OBSNEV), a long-term research project designed to compile socio-ecological information on the major ecosystem types in order to identify the impacts of global change in this area.

  7. Oceanographic Multisensor Buoy Based on Low Cost Sensors for Posidonia Meadows Monitoring in Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Sandra Sendra

    2015-01-01

    Full Text Available There are some underwater areas with high ecological interest that should be monitored. Posidonia and seagrasses exert considerable work in protecting the coastline from erosion. In these areas, many animals and organisms live and find the grassland food and the protection against predators. It is considered a bioindicator of the quality of coastal marine waters. It is important to monitor them and maintain these ecological communities as clean as possible. In this paper, we present an oceanographic buoy for Posidonia meadows monitoring. It is based on a set of low cost sensors which are able to collect data from water such as salinity, temperature, and turbidity and from the weather as temperature, relative humidity, and rainfall, among others. The system is mounted in a buoy which keeps it isolated to possible oxidation problems. Data gathered are processed using a microcontroller. Finally the buoy is connected with a base station placed on the mainland through a wireless connection using a FlyPort module. The network performance is checked in order to ensure that no delays will be generated on the data transmission. This proposal could be used to monitor other areas with special ecological interest and for monitoring and supervising aquaculture activities.

  8. Contribution of seagrass plants to CO2 capture in a tropical seagrass meadow under experimental disturbance.

    Science.gov (United States)

    Deyanova, Diana; Gullström, Martin; Lyimo, Liberatus D; Dahl, Martin; Hamisi, Mariam I; Mtolera, Matern S P; Björk, Mats

    2017-01-01

    Coastal vegetative habitats are known to be highly productive environments with a high ability to capture and store carbon. During disturbance this important function could be compromised as plant photosynthetic capacity, biomass, and/or growth are reduced. To evaluate effects of disturbance on CO2 capture in plants we performed a five-month manipulative experiment in a tropical seagrass (Thalassia hemprichii) meadow exposed to two intensity levels of shading and simulated grazing. We assessed CO2 capture potential (as net CO2 fixation) using areal productivity calculated from continuous measurements of diel photosynthetic rates, and estimates of plant morphology, biomass and productivity/respiration (P/R) ratios (from the literature). To better understand the plant capacity to coping with level of disturbance we also measured plant growth and resource allocation. We observed substantial reductions in seagrass areal productivity, biomass, and leaf area that together resulted in a negative daily carbon balance in the two shading treatments as well as in the high-intensity simulated grazing treatment. Additionally, based on the concentrations of soluble carbohydrates and starch in the rhizomes, we found that the main reserve sources for plant growth were reduced in all treatments except for the low-intensity simulated grazing treatment. If permanent, these combined adverse effects will reduce the plants' resilience and capacity to recover after disturbance. This might in turn have long-lasting and devastating effects on important ecosystem functions, including the carbon sequestration capacity of the seagrass system.

  9. Palaeoclimatic conditions in the Mediterranean explain genetic diversity of Posidonia oceanica seagrass meadows

    KAUST Repository

    Chefaoui, Rosa M.

    2017-05-26

    Past environmental conditions in the Mediterranean Sea have been proposed as main drivers of the current patterns of distribution of genetic structure of the seagrass Posidonia oceanica, the foundation species of one of the most important ecosystems in the Mediterranean Sea. Yet, the location of cold climate refugia (persistence regions) for this species during the Last Glacial Maximum (LGM) is not clear, precluding the understanding of its biogeographical history. We used Ecological Niche Modelling together with existing phylogeographic data to locate Pleistocene refugia in the Mediterranean Sea and to develop a hypothetical past biogeographical distribution able to explain the genetic diversity presently found in P. oceanica meadows. To do that, we used an ensemble approach of six predictive algorithms and two Ocean General Circulation Models. The minimum SST in winter and the maximum SST in summer allowed us to hindcast the species range during the LGM. We found separate glacial refugia in each Mediterranean basin and in the Central region. Altogether, the results suggest that the Central region of the Mediterranean Sea was the most relevant cold climate refugium, supporting the hypothesis that long-term persistence there allowed the region to develop and retain its presently high proportion of the global genetic diversity of P. oceanica.

  10. Light availability and temperature, not increased CO2, will structure future meadows of Posidonia oceanica

    KAUST Repository

    Hendriks, Iris E.; Olsen, Ylva S.; Duarte, Carlos M.

    2017-01-01

    We evaluated the photosynthetic performance of Posidonia oceanica during short-term laboratory exposures to ambient and elevated temperatures (24–25°C and 29–30°C) warming and pCO2 (380, 750 and 1000ppm pCO2) under normal and low light conditions (200 and 40μmol photons m−2s−1 respectively). Plant growth was measured at the low light regime and showed a negative response to warming. Light was a critical factor for photosynthetic performance, although we found no evidence of compensation of photosynthetic quantum efficiency in high light. Relative Electron Rate Transport (rETRmax) was higher in plants incubated in high light, but not affected by pCO2 or temperature. The saturation irradiance (Ik) was negatively affected by temperature. We conclude that elevated CO2 does not enhance photosynthetic activity and growth, in the short term for P. oceanica, while temperature has a direct negative effect on growth. Low light availability also negatively affected photosynthetic performance during the short experimental period examined here. Therefore increasing concentrations of CO2 may not compensate for predicted future conditions of warmer water and higher turbidity for seagrass meadows.

  11. Net primary productivity and its partitioning in response to precipitation gradient in an alpine meadow.

    Science.gov (United States)

    Zhang, Fangyue; Quan, Quan; Song, Bing; Sun, Jian; Chen, Youjun; Zhou, Qingping; Niu, Shuli

    2017-11-09

    The dynamics of net primary productivity (NPP) and its partitioning to the aboveground versus belowground are of fundamental importance to understand carbon cycling and its feedback to climate change. However, the responses of NPP and its partitioning to precipitation gradient are poorly understood. We conducted a manipulative field experiment with six precipitation treatments (1/12 P, 1/4 P, 1/2 P, 3/4 P, P, and 5/4 P, P is annual precipitation) in an alpine meadow to examine aboveground and belowground NPP (ANPP and BNPP) in response to precipitation gradient in 2015 and 2016. We found that changes in precipitation had no significant impact on ANPP or belowground biomass in 2015. Compared with control, only the extremely drought treatment (1/12 P) significantly reduced ANPP by 37.68% and increased BNPP at the depth of 20-40 cm by 80.59% in 2016. Across the gradient, ANPP showed a nonlinear response to precipitation amount in 2016. Neither BNPP nor NPP had significant relationship with precipitation changes. The variance in ANPP were mostly due to forbs production, which was ultimately caused by altering soil water content and soil inorganic nitrogen concentration. The nonlinear precipitation-ANPP relationship indicates that future precipitation changes especially extreme drought will dramatically decrease ANPP and push this ecosystem beyond threshold.

  12. Palaeoclimatic conditions in the Mediterranean explain genetic diversity of Posidonia oceanica seagrass meadows

    KAUST Repository

    Chefaoui, Rosa M.; Duarte, Carlos M.; Serrã o, Ester A.

    2017-01-01

    Past environmental conditions in the Mediterranean Sea have been proposed as main drivers of the current patterns of distribution of genetic structure of the seagrass Posidonia oceanica, the foundation species of one of the most important ecosystems in the Mediterranean Sea. Yet, the location of cold climate refugia (persistence regions) for this species during the Last Glacial Maximum (LGM) is not clear, precluding the understanding of its biogeographical history. We used Ecological Niche Modelling together with existing phylogeographic data to locate Pleistocene refugia in the Mediterranean Sea and to develop a hypothetical past biogeographical distribution able to explain the genetic diversity presently found in P. oceanica meadows. To do that, we used an ensemble approach of six predictive algorithms and two Ocean General Circulation Models. The minimum SST in winter and the maximum SST in summer allowed us to hindcast the species range during the LGM. We found separate glacial refugia in each Mediterranean basin and in the Central region. Altogether, the results suggest that the Central region of the Mediterranean Sea was the most relevant cold climate refugium, supporting the hypothesis that long-term persistence there allowed the region to develop and retain its presently high proportion of the global genetic diversity of P. oceanica.

  13. Invasive species in the flora of the Starobilsk grass-meadow steppe (Ukraine

    Directory of Open Access Journals (Sweden)

    Kucher Oksana O.

    2015-06-01

    Full Text Available The results of an investigation of the invasive species in the flora of the Starobilsk grass-meadow steppe are presented. Check-list of alien plant has over 386 species of vascular plants of which 28 species are invasive. We have identified 6 transformer species from the invasive plants. We aggregate data on the entry, distribution history, ecology, occurrence in different plant communities, degree of their naturalization and the habitats where they occur. The leading families of invasive species are: Asteraceae. The basis for this group is presented by origin from the North America and the Mediterranean. With respect to the time of immigration, most of them are kenophytes. By the method of introduction, ksenophytes are dominated; according to the degree of naturalization epoecophytes and agriophytes dominate in this group. With regard to the characteristics of life forms, half of invasive species are terophytes. The vast majority of plants are heliophytes and xeromesophytes. Most species are found in biotopes group I: Cultivated agricultural biotopes; least of all species found in biotopes group F: Biotopes dominated by chamephytes and nanophanerophytes. Only 3 species found in biotopes group F: Biotopes dominated by chamephytesand nanophanerophytes. The maps of distribution of 28 invasive species are provided. Most of the species marked dispersed in more than 30 squares.

  14. Spatial requirements of free-ranging Huon tree kangaroos, Dendrolagus matschiei (Macropodidae, in upper montane forest.

    Directory of Open Access Journals (Sweden)

    Gabriel Porolak

    Full Text Available Tree kangaroos (Macropodidae, Dendrolagus are some of Australasia's least known mammals. However, there is sufficient evidence of population decline and local extinctions that all New Guinea tree kangaroos are considered threatened. Understanding spatial requirements is important in conservation and management. Expectations from studies of Australian tree kangaroos and other rainforest macropodids suggest that tree kangaroos should have small discrete home ranges with the potential for high population densities, but there are no published estimates of spatial requirements of any New Guinea tree kangaroo species. Home ranges of 15 Huon tree kangaroos, Dendrolagus matschiei, were measured in upper montane forest on the Huon Peninsula, Papua New Guinea. The home range area was an average of 139.6±26.5 ha (100% MCP; n = 15 or 81.8±28.3 ha (90% harmonic mean; n = 15, and did not differ between males and females. Home ranges of D. matschiei were 40-100 times larger than those of Australian tree kangaroos or other rainforest macropods, possibly due to the impact of hunting reducing density, or low productivity of their high altitude habitat. Huon tree kangaroos had cores of activity within their range at 45% (20.9±4.1 ha and 70% (36.6±7.5 ha harmonic mean isopleths, with little overlap (4.8±2.9%; n = 15 pairs between neighbouring females at the 45% isopleth, but, unlike the Australian species, extensive overlap between females (20.8±5.5%; n = 15 pairs at the complete range (90% harmonic mean. Males overlapped each other and females to a greater extent than did pairs of females. From core areas and overlap, the density of female D. matschiei was one per 19.4 ha. Understanding the cause of this low density is crucial in gaining greater understanding of variations in density of tree kangaroos across the landscape. We consider the potential role of habitat fragmentation, productivity and hunting pressure in limiting tree kangaroo

  15. Tropical Montane Cloud Forests: Hydrometeorological variability in three neighbouring catchments with different forest cover

    Science.gov (United States)

    Ramírez, Beatriz H.; Teuling, Adriaan J.; Ganzeveld, Laurens; Hegger, Zita; Leemans, Rik

    2017-09-01

    Mountain areas are characterized by a large heterogeneity in hydrological and meteorological conditions. This heterogeneity is currently poorly represented by gauging networks and by the coarse scale of global and regional climate and hydrological models. Tropical Montane Cloud Forests (TMCFs) are found in a narrow elevation range and are characterized by persistent fog. Their water balance depends on local and upwind temperatures and moisture, therefore, changes in these parameters will alter TMCF hydrology. Until recently the hydrological functioning of TMCFs was mainly studied in coastal regions, while continental TMCFs were largely ignored. This study contributes to fill this gap by focusing on a TMCF which is located on the northern eastern Andes at an elevation of 1550-2300 m asl, in the Orinoco river basin highlands. In this study, we describe the spatial and seasonal meteorological variability, analyse the corresponding catchment hydrological response to different land cover, and perform a sensitivity analysis on uncertainties related to rainfall interpolation, catchment area estimation and streamflow measurements. Hydro-meteorological measurements, including hourly solar radiation, temperature, relative humidity, wind speed, precipitation, soil moisture and streamflow, were collected from June 2013 to May 2014 at three gauged neighbouring catchments with contrasting TMCF/grassland cover and less than 250 m elevation difference. We found wetter and less seasonally contrasting conditions at higher elevations, indicating a positive relation between elevation and fog or rainfall persistence. This pattern is similar to that of other eastern Andean TMCFs, however, the study site had higher wet season rainfall and lower dry season rainfall suggesting that upwind contrasts in land cover and moisture can influence the meteorological conditions at eastern Andean TMCFs. Contrasting streamflow dynamics between the studied catchments reflect the overall system response

  16. Dinitrogen emissions as an overlooked component of the N balance of montane grasslands

    Science.gov (United States)

    Zistl-Schlingmann, M.; Feng, J.; Ralf, K.; Stephan, R.; Dannenmann, M.

    2017-12-01

    component in the N balance of montane grassland ecosystems and thus unalienable for the calculation of N balances in comparable ecosystems.

  17. Distribution patterns of Syllidae (Annelida: Polychaeta from seagrass (Zostera marina and Z. noltei meadows in the Ensenada de O Grove (Galicia, NW Spain

    Directory of Open Access Journals (Sweden)

    Patricia Quintas

    2013-09-01

    Full Text Available This paper describes the distribution and composition of the syllid fauna inhabiting seagrass meadows in the Ensenada de O Grove (NW Spain. Samples were collected on muddy sediments colonized by either Zostera marina L., Zostera noltei Hornemann or by a mixed meadow with both species. Syllids were dominant (13340 individuals; 37% of total polychaete abundance, including 22 species (12 genera. The mixed meadows housed the highest number of species and the Z. noltei meadow had practically no syllids. The dominant species were Exogone naidina, Parapionosyllis elegans, Parexogone hebes and Prosphaerosyllis campoyi ( > 80% of total abundance. Carnivores (mainly species of Parapionosyllis, Amblyosyllis, and Streptosyllis were dominant, especially in muddy sand with either Z. marina or Z. noltei and sandy mud with a mixed meadow. The most important abiotic variables for explaining the composition and distribution of the syllid fauna were bottom water salinity, sorting coefficient and carbonate content. The highest number of species was recorded at sites with a high salinity and carbonate content and the lowest at sites with a high sorting coefficient.

  18. Mapping of Posidonia oceanica (L. Delile Meadows Using Geographic Information Systems: A case study in Ufakdere - Kaş (Mediterranean Sea

    Directory of Open Access Journals (Sweden)

    Volkan Demir

    2016-12-01

    Full Text Available Posidonia oceanica (Linnaeus Delile 1813 is an endemic and the most widespread seagrass species of the Mediterranean Sea. Seagrass meadows are one of the most productive ecosystems on Earth, providing habitat to numerous organisms. Therefore, mapping of seagrass meadows is of crucial importance for conservation and coastal management purposes. Here we present an integrated geographic information system approach with SCUBA diving, providing a cost effective method to monitor seagrass beds at shallow coastal habitats. In this case study P. oceanica meadows were mapped in Ufakdere region of Kaş (Antalya coastal area between April – September 2015. A total of 25000 m2 are were screened to create seagrass coverage maps. Results indicate that P. oceanica meadows cover 21200 m2 and we estimated that 520 m2 of this area is highly damaged. This integrated approach provided one of the most detailed small-scale Posidonia mapping in Turkey and this time and cost effective methodology can be applied to any seagrass meadow with great ease to increase our knowledge on this important habitat.

  19. Molecular characterisation and interpretation of genetic diversity within globally distributed germplasm collections of tall fescue (Festuca arundinacea Schreb.) and meadow fescue (F. pratensis Huds.).

    Science.gov (United States)

    Hand, Melanie L; Cogan, Noel O I; Forster, John W

    2012-04-01

    Allohexaploid tall fescue (Festuca arundinacea Schreb. syn. Lolium arundinaceum [Schreb.] Darbysh.) is an agriculturally important grass cultivated for pasture and turf world-wide. Genetic improvement of tall fescue could benefit from the use of non-domesticated germplasm to diversify breeding populations through the incorporation of novel and superior allele content. However, such potential germplasm must first be characterised, as three major morphotypes (Continental, Mediterranean and rhizomatous) with varying degrees of hybrid interfertility are commonly described within this species. As hexaploid tall fescue is also a member of a polyploid species complex that contains tetraploid, octoploid and decaploid taxa, it is also possible that germplasm collections may have inadvertently sampled some of these sub-species. In this study, 1,040 accessions from the publicly available United States Department of Agriculture tall fescue and meadow fescue germplasm collections were investigated. Sequence of the chloroplast genome-located matK gene and the nuclear ribosomal DNA internal transcribed spacer (rDNA ITS) permitted attribution of accessions to the three previously known morphotypes and also revealed the presence of tall fescue sub-species of varying ploidy levels, as well as other closely related species. The majority of accessions were, however, identified as Continental hexaploid tall fescue. Analysis using 34 simple sequence repeat markers was able to further investigate the level of genetic diversity within each hexaploid tall fescue morphotype group. At least two genetically distinct sub-groups of Continental hexaploid tall fescue were identified which are probably associated with palaeogeographic range expansion of this morphotype. This work has comprehensively characterised a large and complex germplasm collection and has identified genetically diverse accessions which may potentially contribute valuable alleles at agronomic loci for tall fescue cultivar

  20. Comparison of hay and haylage from permanent Alpine meadows in winter dairy cow diets.

    Science.gov (United States)

    Borreani, G; Giaccone, D; Mimosi, A; Tabacco, E

    2007-12-01

    In an Alpine environment, diets based on local forage resources are needed to maintain the link with the territory and confer special characteristics to typical cheeses. Harvesting at a late stage of maturity, high mechanical losses, and frequent rainfall often make the hay that is harvested of a poor quality. The aim of this study was to evaluate the effects of 2 different conservation methods (late hay, LH, vs. early haylage, ES) of natural permanent meadows on milk production in dairy cows, on the chemical and microbiological characteristics of the milk, and on the quality of the cheese over the winter period. Haylage and hay were harvested from the same permanent meadow at the Vittorino Vezzani experimental farm in Sauze d'Oulx (45 degrees 02'N, 6 degrees 53'E, Italy). The ES forage was cut 4 wk earlier than traditional hay, wilted for 30 h, baled at a dry matter (DM) content of about 50%, wrapped with 6 layers of stretch film, and stored in a protected area. The LH forage was harvested later, when the weather conditions were favorable and, after a 3-d wilting, it was baled and stored indoors. After an 8-mo storage period, the ES had a greater crude protein concentration, organic matter digestibility, and net energy for lactation than LH and a lower neutral detergent fiber and acid detergent fiber. Forty multiparous lactating Aosta Red Pied cows were used in a 19-d period crossover design to assess the nutritional value of the stored forages. The diets included ES fed ad libitum and 3.5 kg of DM per cow of concentrate or LH fed ad libitum and 5.1 kg of DM per cow of concentrate. The dietary DM was 90.1% for the LH and 59.9% for the ES. The diets contained 12.6 and 13.0% crude protein and 48.6 and 48.0% neutral detergent fiber, for the LH and ES, respectively. The forage intake was greater in the ES treatment than in the LH treatment. The ES treatment produced more milk (1.7 kg/d) and more 3.5% fat-corrected milk (1.5 kg/d) than the cows on the LH treatment. The

  1. Estimating above-ground biomass on mountain meadows and pastures through remote sensing

    Science.gov (United States)

    Barrachina, M.; Cristóbal, J.; Tulla, A. F.

    2015-06-01

    Extensive stock-breeding systems developed in mountain areas like the Pyrenees are crucial for local farming economies and depend largely on above-ground biomass (AGB) in the form of grass produced on meadows and pastureland. In this study, a multiple linear regression analysis technique based on in-situ biomass collection and vegetation and wetness indices derived from Landsat-5 TM data is successfully applied in a mountainous Pyrenees area to model AGB. Temporal thoroughness of the data is ensured by using a large series of images. Results of on-site AGB collection show the importance for AGB models to capture the high interannual and intraseasonal variability that results from both meteorological conditions and farming practices. AGB models yield best results at midsummer and end of summer before mowing operations by farmers, with a mean R2, RMSE and PE for 2008 and 2009 midsummer of 0.76, 95 g m-2 and 27%, respectively; and with a mean R2, RMSE and PE for 2008 and 2009 end of summer of 0.74, 128 g m-2 and 36%, respectively. Although vegetation indices are a priori more related with biomass production, wetness indices play an important role in modeling AGB, being statistically selected more frequently (more than 50%) than other traditional vegetation indexes (around 27%) such as NDVI. This suggests that middle infrared bands are crucial descriptors of AGB. The methodology applied in this work compares favorably with other works in the literature, yielding better results than those works in mountain areas, owing to the ability of the proposed methodology to capture natural and anthropogenic variations in AGB which are the key to increasing AGB modeling accuracy.

  2. Provenance of radioactive placers, Big Meadow area, Valley and Boise Counties, Idaho

    International Nuclear Information System (INIS)

    Truesdell, D.; Wegrzyn, R.; Dixon, M.

    1977-02-01

    For many years, radioactive black-sand placers have been known to be present in the Bear Valley area of west-central Idaho. The largest of these is in Big Meadow, near the head of Bear Valley Creek. Presence of these placers suggests that low-grade uranium deposits might occur in rocks of the Idaho Batholith, adjacent to Bear Valley. This study was undertaken to locate the provenance of the radioactive minerals and to identify problems that need to be solved before undertaking further investigations. The principal radioactive minerals in these placers are monazite and euxenite. Other minerals include columbite, samarskite, fergusonite, xenotime, zircon, allanite, sphene, and brannerite. Only brannerite is a uranium mineral; the others contain uranium as an impurity in crystal lattices. Radiometric determinations of the concentration of uranium in stream sediments strongly indicate that the radioactive materials originate in an area drained by Casner and Howard Creeks. Equivalent uranium levels in bedrock are highest on the divide between Casner and Howard Creeks. However, this area is not known to contain low-grade uranium occurrences. Euxenite, brannerite, columbite-tantalite, samarskite, and allanite are the principal radioactive minerals that were identified in rock samples. These minerals were found in granite pegmatites, granites, and quartz monzonites. Appreciably higher equivalent uranium concentrations were also found within these rock types. The major problem encountered in this study was the difficulty in mapping bedrock because of extensive soil and glacial mantle. A partial solution to this problem might be the application of radon emanometry so that radiometric measurements would not be limited to the sparse bedrock samples

  3. The influence of hydrologic connectivity on ecosystem metabolism and nitrate uptake in an active beaver meadow

    Science.gov (United States)

    Wegener, P.; Covino, T. P.; Wohl, E.; Kampf, S. K.; Lacy, S.

    2015-12-01

    Wetlands have been widely demonstrated to provide important watershed services, such as the sequestration of carbon (C) and removal of nitrate (NO3-) from through-flowing water. Hydrologic connectivity (degree of water and associated material exchange) between floodplain water bodies (e.g., side channels, ponds) and the main channel influence rates of C accumulation and NO3- uptake, and the degree to which wetlands contribute to enhanced water quality at the catchment scale. However, environmental engineers have largely ignored the role of hydrologic connectivity in providing essential ecosystem services, and constructed wetlands are commonly built using compacted clay and berms that result in less groundwater and surface water exchange than observed in natural wetlands. In a study of an active beaver meadow (multithreaded, riparian wetland) in Rocky Mountain National Park, CO, we show how shifts in hydrology (connectivity, residence times, flow paths) from late spring snowmelt (high connectivity) to autumn/winter baseflow (low connectivity) influence ecosystem metabolism metrics (e.g., gross primary production, ecosystem respiration, and net ecosystem productivity) and NO3- uptake rates. We use a combination of mixing analyses, tracer tests, and hydrometric methods to evaluate shifts in surface and subsurface hydrologic connections between floodplain water bodies from snowmelt to baseflow. In the main channel and three floodplain water bodies, we quantify metabolism metrics and NO3- uptake kinetics across shifting flow regimes. Results from our research indicate that NO3- uptake and metabolism dynamics respond to changing levels of hydrologic connectivity to the main channel, emphasizing the importance of incorporating connectivity in wetland mitigation practices that seek to enhance water quality at the catchment scale.

  4. Grazing intensity on the plant diversity of alpine meadow in the eastern Tibetan plateau

    Directory of Open Access Journals (Sweden)

    Wu Ning

    2004-04-01

    Full Text Available Because ofthe remoteness and harsh conditions of the high-altitude rangelands on the eastern Tibetan Plateau, the relationship between yak grazing and plant diversity has not been so clear although livestock increase was thought as the main issue leading to the degradation of rangeland. In the debate of rangeland degradation, biodiversity loss has been assumed as one of the indicators in the last two decades. In this paper authors measured the effects of different grazing intensities on the plant diversity and the structure of Kobresia pygmaea community in the case-study area, northwestern Sichuan. The results indicated that plant diversity of alpine meadow has different changing trends respectively with the change of grazing intensity and seasons. In June the highest plant diversity occurred in the intensively grazed (HG plots, but in July and September species biodiversity index of slightly grazed (LG plots is higher than other experimental treatments. In August the intermediate grazed (IG plots has the highest biodiversity index. Moreover, it was found that intensively grazing always leads to the increase of plant density, but meanwhile the decrease of community height, coverage and biomass. Over-grazing can change the community structure and lead to the succession from Kobresia pygmaea dominated community to Poa pratensis dominated. Analyzing results comprehensively, it can be suggested that the relationship between grazing intensity and plant diversity is not linear, i.e. diversity index is not as good as other characteristics of community structure to evaluate rangeland degradation on the high altitude situation. The change of biodiversity is so complicated that it can not be explained with the simple corresponding causality.

  5. Morphological and colour morph clines along an altitudinal gradient in the meadow grasshopper Pseudochorthippus parallelus.

    Science.gov (United States)

    Köhler, Günter; Samietz, Jörg; Schielzeth, Holger

    2017-01-01

    Many animals show altitudinal clines in size, shape and body colour. Increases in body size and reduction in the length of body appendices in colder habitats are usually attributed to improved heat conservation at lower surface-to-volume ratios (known as Bergmann's and Allen's rule, respectively). However, the patterns are more variable and sometimes reversed in small ectotherms that are affected by shortened growing seasons. Altitude can also affect colouration. The thermal melanism hypothesis predicts darker colours under cooler conditions because of a thermoregulatory advantage. Darker colours may also be favoured at high altitudes for reasons of UV protection or habitat-dependent crypsis. We studied altitudinal variation in morphology and colour in the colour-polymorphic meadow grasshopper Pseudochorthippus parallelus based on 563 individuals from 17 populations sampled between 450 and 2,500 m asl. Pronotum length did not change with altitude, while postfemur length decreased significantly in both sexes. Tegmen (forewing) length decreased in males, but not in females. The results indicate that while body size, as best quantified by pronotum length, was remarkably constant, extended appendices were reduced at high altitudes. The pattern thus follows Allen's rule, but neither Bergmann's nor converse Bergmann's rule. These results indicate that inference of converse Bergmann's rule based on measurements from appendices should be treated with some caution. Colour morph ratios showed significant changes in both sexes from lowland populations dominated by green individuals to high-altitude populations dominated by brown ones. The increase of brown morphs was particularly steep between 1,500 and 2,000 m asl. The results suggest shared control of colour in males and females and local adaptation along the altitudinal gradient following the predictions of the thermal melanism hypothesis. Interestingly, both patterns, the reduction of body appendices and the higher

  6. Morphological and colour morph clines along an altitudinal gradient in the meadow grasshopper Pseudochorthippus parallelus.

    Directory of Open Access Journals (Sweden)

    Günter Köhler

    Full Text Available Many animals show altitudinal clines in size, shape and body colour. Increases in body size and reduction in the length of body appendices in colder habitats are usually attributed to improved heat conservation at lower surface-to-volume ratios (known as Bergmann's and Allen's rule, respectively. However, the patterns are more variable and sometimes reversed in small ectotherms that are affected by shortened growing seasons. Altitude can also affect colouration. The thermal melanism hypothesis predicts darker colours under cooler conditions because of a thermoregulatory advantage. Darker colours may also be favoured at high altitudes for reasons of UV protection or habitat-dependent crypsis. We studied altitudinal variation in morphology and colour in the colour-polymorphic meadow grasshopper Pseudochorthippus parallelus based on 563 individuals from 17 populations sampled between 450 and 2,500 m asl. Pronotum length did not change with altitude, while postfemur length decreased significantly in both sexes. Tegmen (forewing length decreased in males, but not in females. The results indicate that while body size, as best quantified by pronotum length, was remarkably constant, extended appendices were reduced at high altitudes. The pattern thus follows Allen's rule, but neither Bergmann's nor converse Bergmann's rule. These results indicate that inference of converse Bergmann's rule based on measurements from appendices should be treated with some caution. Colour morph ratios showed significant changes in both sexes from lowland populations dominated by green individuals to high-altitude populations dominated by brown ones. The increase of brown morphs was particularly steep between 1,500 and 2,000 m asl. The results suggest shared control of colour in males and females and local adaptation along the altitudinal gradient following the predictions of the thermal melanism hypothesis. Interestingly, both patterns, the reduction of body appendices and

  7. Effect of fertilization and harvest frequency on floristic composition and yields of meadow stand

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    Josef Raus

    2012-01-01

    Full Text Available The effect of fertilization and the harvest frequency on production and floristic characteristics of a meadow stand were assessed in a small plot trial established in 2003 in Vatín, Vysočina Region, the Czech Republic. Four levels of fertilization (none; N0 + P30 + K60 kg∙ha−1; N90 + P30 + K60 kg∙ha−1; N180 + P30 + K60 kg∙ha−1 were combined with four treatments of exploitation intensity (4 cuts per year, first cut on 15th May, every next after 45 days; 3 cuts per year, first cut on 30th May, every next after 60 days; 2 cuts per year, first cut on 15th June, next after 90 days; 2 cuts per year, first cut on 30th June, next after 90 days. Production of dry matter and proportions of guilds (grasses, legumes, and other species were evaluated. Data from 2009–2011 were used in this paper. Yields of the dry matter increased along with increasing amounts of nutrients supplied and ranged from 3.8 t∙ha−1 (non-fertilized to 9.1 t∙ha−1 (N180PK. The nutrition level had a significant effect on spread of grasses, which reached maximal proportion of 52.3 % under N180PK fertilization compared to 42.1% on non-fertilized plots. On the contrary, legumes flourished well in treatments without N-supply, attaining proportion of 6.8 % and 5.1 % on PK-fertilized and non-fertilized plot, respectively. With regard to the exploitation intensity grasses profited from extensive management by contrast to the group of other species which reached its maximum in swards harvested four times a year. Proportions of legumes did not show significant dependence on the cutting frequency.

  8. Spatially explicit feedbacks between seagrass meadow structure, sediment and light: Habitat suitability for seagrass growth

    Science.gov (United States)

    Carr, Joel; D'Odorico, Paul; McGlathery, Karen; Wiberg, Patricia L.

    2016-01-01

    In shallow coastal bays where nutrient loading and riverine inputs are low, turbidity, and the consequent light environment are controlled by resuspension of bed sediments due to wind-waves and tidal currents. High sediment resuspension and low light environments can limit benthic primary productivity; however, both currents and waves are affected by the presence of benthic plants such as seagrass. This feedback between the presence of benthic primary producers such as seagrass and the consequent light environment has been predicted to induce bistable dynamics locally. However, these vegetated areas influence a larger area than they footprint, including a barren adjacent downstream area which exhibits reduced shear stresses. Here we explore through modeling how the patchy structure of seagrass meadows on a landscape may affect sediment resuspension and the consequent light environment due to the presence of this sheltered region. Heterogeneous vegetation covers comprising a mosaic of randomly distributed patches were generated to investigate the effect of patch modified hydrodynamics. Actual cover of vegetation on the landscape was used to facilitate comparisons across landscape realizations. Hourly wave and current shear stresses on the landscape along with suspended sediment concentration and light attenuation characteristics were then calculated and spatially averaged to examine how actual cover and mean water depth affect the bulk sediment and light environment. The results indicate that an effective cover, which incorporates the sheltering area, has important controls on the distributions of shear stress, suspended sediment, light environment, and consequent seagrass habitat suitability. Interestingly, an optimal habitat occurs within a depth range where, if actual cover is reduced past some threshold, the bulk light environment would no longer favor seagrass growth.

  9. Antennal olfactory responses of adult meadow spittlebug, Philaenus spumarius, to volatile organic compounds (VOCs.

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    Giacinto Salvatore Germinara

    Full Text Available The meadow spittlebug, Philaenus spumarius L. (Hemiptera, Aphrophoridae is a commonly found vector of Xylella fastidiosa Wells et al. (1987 strain subspecies pauca associated with the "Olive Quick Decline Syndrome" in Italy. To contribute to the knowledge of the adult P. spumarius chemoreceptivity, electroantennographic (EAG responses of both sexes to 50 volatile organic compounds (VOCs including aliphatic aldehydes, alcohols, esters, and ketones, terpenoids, and aromatics were recorded. Measurable EAG responses were elicited by all compounds tested. In both sexes, octanal, 2-octanol, 2-decanone, (E-2-hexenyl acetate, and vanillin elicited the strongest antennal amplitude within the chemical groups of aliphatic saturated aldehydes, aliphatic alcohols, aliphatic acetates and aromatics, respectively. Male and female EAG responses to sulcatol, (±linalool, and sulcatone were higher than those to other terpenoinds. In both sexes, the weakest antennal stimulants were phenethyl alcohol and 2-pentanone. Sexual differences in the EAG amplitude were found only for four of test compounds suggesting a general similarity between males and females in antennal sensitivity. The olfactory system of both sexes proved to be sensitive to changes in stimulus concentration, carbon chain length, and compound structure. Compounds with short carbon chain length (C5-C6 elicited lower EAG amplitudes than compounds with higher carbon chain length (C9-C10 in all classes of aliphatic hydrocarbons with different functional groups. The elucidation of the sensitivity profile of P. spumarius to a variety of VOCs provides a basis for future identification of behaviorally-active compounds useful for developing semiochemical-based control strategies of this pest.

  10. Initial shifts in nitrogen impact on ecosystem carbon fluxes in an alpine meadow: patterns and causes

    Science.gov (United States)

    Song, Bing; Sun, Jian; Zhou, Qingping; Zong, Ning; Li, Linghao; Niu, Shuli

    2017-09-01

    Increases in nitrogen (N) deposition can greatly stimulate ecosystem net carbon (C) sequestration through positive N-induced effects on plant productivity. However, how net ecosystem CO2 exchange (NEE) and its components respond to different N addition rates remains unclear. Using an N addition gradient experiment (six levels: 0, 2, 4, 8, 16, 32 gN m-2 yr-1) in an alpine meadow on the Qinghai-Tibetan Plateau, we explored the responses of different ecosystem C fluxes to an N addition gradient and revealed mechanisms underlying the dynamic responses. Results showed that NEE, ecosystem respiration (ER), and gross ecosystem production (GEP) all increased linearly with N addition rates in the first year of treatment but shifted to N saturation responses in the second year with the highest NEE (-7.77 ± 0.48 µmol m-2 s-1) occurring under an N addition rate of 8 gN m-2 yr-1. The saturation responses of NEE and GEP were caused by N-induced accumulation of standing litter, which limited light availability for plant growth under high N addition. The saturation response of ER was mainly due to an N-induced saturation response of aboveground plant respiration and decreasing soil microbial respiration along the N addition gradient, while decreases in soil microbial respiration under high N addition were caused by N-induced reductions in soil pH. We also found that various components of ER, including aboveground plant respiration, soil respiration, root respiration, and microbial respiration, responded differentially to the N addition gradient. These results reveal temporal dynamics of N impacts and the rapid shift in ecosystem C fluxes from N limitation to N saturation. Our findings bring evidence of short-term initial shifts in responses of ecosystem C fluxes to increases in N deposition, which should be considered when predicting long-term changes in ecosystem net C sequestration.

  11. Monitoring soil moisture patterns in alpine meadows using ground sensor networks and remote sensing techniques

    Science.gov (United States)

    Bertoldi, Giacomo; Brenner, Johannes; Notarnicola, Claudia; Greifeneder, Felix; Nicolini, Irene; Della Chiesa, Stefano; Niedrist, Georg; Tappeiner, Ulrike

    2015-04-01

    Soil moisture content (SMC) is a key factor for numerous processes, including runoff generation, groundwater recharge, evapotranspiration, soil respiration, and biological productivity. Understanding the controls on the spatial and temporal variability of SMC in mountain catchments is an essential step towards improving quantitative predictions of catchment hydrological processes and related ecosystem services. The interacting influences of precipitation, soil properties, vegetation, and topography on SMC and the influence of SMC patterns on runoff generation processes have been extensively investigated (Vereecken et al., 2014). However, in mountain areas, obtaining reliable SMC estimations is still challenging, because of the high variability in topography, soil and vegetation properties. In the last few years, there has been an increasing interest in the estimation of surface SMC at local scales. On the one hand, low cost wireless sensor networks provide high-resolution SMC time series. On the other hand, active remote sensing microwave techniques, such as Synthetic Aperture Radars (SARs), show promising results (Bertoldi et al. 2014). As these data provide continuous coverage of large spatial extents with high spatial resolution (10-20 m), they are particularly in demand for mountain areas. However, there are still limitations related to the fact that the SAR signal can penetrate only a few centimeters in the soil. Moreover, the signal is strongly influenced by vegetation, surface roughness and topography. In this contribution, we analyse the spatial and temporal dynamics of surface and root-zone SMC (2.5 - 5 - 25 cm depth) of alpine meadows and pastures in the Long Term Ecological Research (LTER) Area Mazia Valley (South Tyrol - Italy) with different techniques: (I) a network of 18 stations; (II) field campaigns with mobile ground sensors; (III) 20-m resolution RADARSAT2 SAR images; (IV) numerical simulations using the GEOtop hydrological model (Rigon et al

  12. Height-diameter allometry and above ground biomass in tropical montane forests: Insights from the Albertine Rift in Africa.

    Science.gov (United States)

    Imani, Gérard; Boyemba, Faustin; Lewis, Simon; Nabahungu, Nsharwasi Léon; Calders, Kim; Zapfack, Louis; Riera, Bernard; Balegamire, Clarisse; Cuni-Sanchez, Aida

    2017-01-01

    Tropical montane forests provide an important natural laboratory to test ecological theory. While it is well-known that some aspects of forest structure change with altitude, little is known on the effects of altitude on above ground biomass (AGB), particularly with regard to changing height-diameter allometry. To address this we investigate (1) the effects of altitude on height-diameter allometry, (2) how different height-diameter allometric models affect above ground biomass estimates; and (3) how other forest structural, taxonomic and environmental attributes affect above ground biomass using 30 permanent sample plots (1-ha; all trees ≥ 10 cm diameter measured) established between 1250 and 2600 m asl in Kahuzi Biega National Park in eastern Democratic Republic of Congo. Forest structure and species composition differed with increasing altitude, with four forest types identified. Different height-diameter allometric models performed better with the different forest types, as trees got smaller with increasing altitude. Above ground biomass ranged from 168 to 290 Mg ha-1, but there were no significant differences in AGB between forests types, as tree size decreased but stem density increased with increasing altitude. Forest structure had greater effects on above ground biomass than forest diversity. Soil attributes (K and acidity, pH) also significantly affected above ground biomass. Results show how forest structural, taxonomic and environmental attributes affect above ground biomass in African tropical montane forests. They particularly highlight that the use of regional height-diameter models introduces significant biases in above ground biomass estimates, and that different height-diameter models might be preferred for different forest types, and these should be considered in future studies.

  13. Nutrient addition modifies phosphatase activities along an altitudinal gradient in a tropical montane forest in Southern Ecuador

    Directory of Open Access Journals (Sweden)

    Karla eDietrich

    2016-02-01

    Full Text Available Atmospheric nutrient deposition and climate change are expected to endanger the diversity of tropical forest ecosystems. Nitrogen (N deposition might influence nutrient fluxes beyond the N cycle by a concomitant increased demand for other nutritional elements such as phosphorus (P. Organisms might respond to the increased P demand by enhanced activity of enzymes involved in releasing inorganic P from organic matter (OM. Our aims were to assess the effect of i climate shifts (approximated by an altitudinal gradient, and ii nutrient addition (N, P, N+P on phosphatase activity (PA in organic layer and mineral soil of a tropical montane rainforest in Southern Ecuador. A nutrient manipulation experiment (NUMEX was set up along an altitudinal gradient (1000, 2000, and 3000 m a.s.l.. We determined PA and inorganic and total P concentrations. PA at 1000 m was significantly lower (mean ± standard error: 48 ± 20 µmol p-NP g-1 dm h-1 as compared to 2000 m and 3000 m (119 ± 11 and 137 ± 19, respectively. One explanation might be that very rapid decomposition of OM at 1000 m results in very thin organic layers reducing the stabilization of enzymes and thus, resulting in leaching loss of enzymes under the humid tropical climate. We found no effect of N addition on PA neither in the organic layer nor in mineral soil, probably because of the low nutrient addition rates that showed ambiguous results so far on productivity measures as a proxy for P demand. In the organic layers of P and N+P treatments, we found decreased PA and increased concentrations of inorganic P. This indicates that the surplus of inorganic P reduced the biosynthesis of phosphatase enzymes. PA in megadiverse montane rainforests is likely to be unaffected by increased atmospheric N deposition but reduced upon atmospheric P deposition.

  14. Seed-deposition and recruitment patterns of Clusia species in a disturbed tropical montane forest in Bolivia

    Science.gov (United States)

    Saavedra, Francisco; Hensen, Isabell; Apaza Quevedo, Amira; Neuschulz, Eike Lena; Schleuning, Matthias

    2017-11-01

    Spatial patterns of seed dispersal and recruitment of fleshy-fruited plants in tropical forests are supposed to be driven by the activity of animal seed dispersers, but the spatial patterns of seed dispersal, seedlings and saplings have rarely been analyzed simultaneously. We studied seed deposition and recruitment patterns of three Clusia species in a tropical montane forest of the Bolivian Andes and tested whether these patterns changed between habitat types (forest edge vs. forest interior), distance to the fruiting tree and consecutive recruitment stages of the seedlings. We recorded the number of seeds deposited in seed traps to assess the local seed-deposition pattern and the abundance and distribution of seedlings and saplings to evaluate the spatial pattern of recruitment. More seeds were removed and deposited at the forest edge than in the interior. The number of deposited seeds decreased with distance from the fruiting tree and was spatially clustered in both habitat types. The density of 1-yr-old seedlings and saplings was higher at forest edges, whereas the density of 2-yr-old seedlings was similar in both habitat types. While seedlings were almost randomly distributed, seeds and saplings were spatially clustered in both habitat types. Our findings demonstrate systematic changes in spatial patterns of recruits across the plant regeneration cycle and suggest that the differential effects of biotic and abiotic factors determine plant recruitment at the edges and in the interior of tropical montane forests. These differences in the spatial distribution of individuals across recruitment stages may have strong effects on plant community dynamics and influence plant species coexistence in disturbed tropical forests.

  15. Impacts of climate and management on water balance and nitrogen leaching from montane grassland soils

    Science.gov (United States)

    Fu, Jin; Gasche, Rainer; Wang, Na; Lu, Haiyan; Butterbach-Bahl, Klaus; Kiese, Ralf

    2017-04-01

    The impacts of climate and management on the water balance and nutrient leaching of montane grasslands have rarely been investigated, though such ecosystems may represent a major source for ground and surface water nitrates. In this study nitrogen (nitrate, ammonium, dissolved organic nitrogen) and dissolved organic carbon leaching as well as water balance components (precipitation, evapotranspiration, and groundwater recharge) were quantified (2012-2014) by means of replicated (N=3 per site/ treatment) measurements of weighable grassland lysimeters (1 m2 area, 1.2 m soil depth) at three sites (E860: 860 m a.s.l., E770: 770 m a.s.l. and E600: 600 m a.s.l.) in the pre-alpine region of S-Germany. Two grassland management strategies were investigated: a) intensive management with 5 cuts per year and cattle slurry application rates of 280 kg N ha-1 yr-1, and b) extensive management with 3 cuts per year and cattle slurry application rates of 56 kg N ha-1 yr-1. Our results show that at E600, the site with highest air temperature (8.6 °C) and lowest precipitation (981.9 mm), evapotranspiration losses were 100.7 mm higher as at the E860 site, i.e. the site with lowest mean annual air temperature (6.5 °C) and highest precipitation (1359.3 mm). On the other hand groundwater recharge was substantial lower at E600 (-440.9 mm) as compared to E860. Compared to climate, impacts of grassland management on water balance components were negligible. However, intensive management significantly increased mean total nitrogen leaching rates across sites as compared to extensive management from 2.6 kg N ha-1 year-1 (range: 0.5-6.0 kg N ha-1 year-1) to 4.8 kg N ha-1 year-1 (range: 0.9-12.9 kg N ha-1 year-1). N leaching losses were dominated by nitrate (64.7 %) and equally less by ammonium (14.6 %) and DON (20.7 %). The rather low rates of N leaching (0.8 - 6.9 % of total applied N) suggest a highly efficient nitrogen uptake by plants as measured by plant total N content at harvest

  16. The potential negative impacts of global climate change on tropical montane cloud forests

    Science.gov (United States)

    Foster, Pru

    2001-10-01

    Nearly every aspect of the cloud forest is affected by regular cloud immersion, from the hydrological cycle to the species of plants and animals within the forest. Since the altitude band of cloud formation on tropical mountains is limited, the tropical montane cloud forest occurs in fragmented strips and has been likened to island archipelagoes. This isolation and uniqueness promotes explosive speciation, exceptionally high endemism, and a great sensitivity to climate. Global climate change threatens all ecosystems through temperature and rainfall changes, with a typical estimate for altitude shifts in the climatic optimum for mountain ecotones of hundreds of meters by the time of CO 2 doubling. This alone suggests complete replacement of many of the narrow altitude range cloud forests by lower altitude ecosystems, as well as the expulsion of peak residing cloud forests into extinction. However, the cloud forest will also be affected by other climate changes, in particular changes in cloud formation. A number of global climate models suggest a reduction in low level cloudiness with the coming climate changes, and one site in particular, Monteverde, Costa Rica, appears to already be experiencing a reduction in cloud immersion. The coming climate changes appear very likely to upset the current dynamic equilibrium of the cloud forest. Results will include biodiversity loss, altitude shifts in species' ranges and subsequent community reshuffling, and possibly forest death. Difficulties for cloud forest species to survive in climate-induced migrations include no remaining location with a suitable climate, no pristine location to colonize, migration rates or establishment rates that cannot keep up with climate change rates and new species interactions. We review previous cloud forest species redistributions in the paleo-record in light of the coming changes. The characteristic epiphytes of the cloud forest play an important role in the light, hydrological and nutrient

  17. Windturbines and meadow birds in Germany - results of a 7 years BACI-study and a literature review

    Energy Technology Data Exchange (ETDEWEB)

    Reichenbach, Marc; Steinborn, Hanjo

    2011-07-01

    Full text: In many parts of Germany meadow birds - either breeding or staging - are the species most affected by wind farms planned in open agricultural areas. A 7 year BACI-study (before-after-control-impact) in the south of East Frisia, Lower Saxony, investigated the influence of wind turbines on several meadow bird species. The parameters analysed comprised population trends, spatial distribution and behaviour in relation to turbine distance, breeding success as well as the influence of certain habitat parameters like type of agricultural use and the distance to woods and hedges. The results show, that breeding birds are generally less sensitive to wind turbines than staging birds. Significant reductions of breeding lapwing density occurred only up to a distance of 100 m. Curlews however showed a reduction of resting and grooming behaviour up to a distance of 250 m. Other species like meadow pipit, skylark and stonechat showed no indications of displacement. An impact of wind turbines on breeding success could not be detected. Breeding lapwings showed a strong preference for certain types of crops, which led to spatial aggregations irrespective of turbine proximity. In staging birds a much more obvious displacement up to about 400 m could be detected. The results are consistent with a number of other German studies on possible displacement effects in different bird species. Lapwing and skylark are among the best studied species whereas staging geese tend to be the most sensitive ones. In conclusion the siting of wind farms must not only be guided by occurrence of endangered species named on national or regional Red Lists but also by the species-specific sensitivity against the disturbance effects of wind turbines. (Author)

  18. Evapotranspiration partitioning in the highest alpine meadow zones through in-situ chamber and dual stable water isotope approaches

    Science.gov (United States)

    Cui, J.; Tian, L.

    2017-12-01

    Understanding plant functionality within the water cycles of grassland ecosystems is crucial for obtaining both regional water balance and plant adaptability in the context of ongoing climate change. The transpiration to evapotranspiration ratio (T/ET) is an indicator of plant's contribution to ecosystem water cycle. In this study, we used high-frequency laser spectroscopy (L2130-i), three custom-built chambers, and eddy covariance techniques, to constrain the role played by plants in evapotranspiration over an alpine meadow ecosystem in the central Tibetan Plateau (TP). Three different sizes of chambers are used to direct measure the isotopic compositions in evapotranspiration (δET), evaporation (δE) and transpiration (δT). The consistent T/ET between δ18O and δD manifests that chamber and dual isotope tracers are robust methods to estimate T/ET in alpine meadow zone. Sensitivity analysis shows that the isotopic composition of evapotranspiration is the main contributor to, and the uncertainty source for, the T/ET estimate. The influence of meteorological and biotic factors on T/ET is also discussed. The results from this study indicate that plants play an important role in the water cycles of alpine meadow ecosystems despite the sparse distribution of plant cover. We also synthesized the published T/ET data over the entire TP region, and found a good relation between T/ET and leaf area index (LAI). Moreover, soil water content played some role in controlling T/ET beyond the LAI in arid/semiarid regions such as the TP. More than half of the TP is covered by grassland, but its low biomass and shallow rooting depth make it very vulnerable to climate change variables such as air temperature warming and variations in precipitation. Given the crucial role played by plants in an ecosystem's water cycle, any variations in grassland cover are likely to exert a critical impact on the regional hydrological cycle, and even the regional climate.

  19. The discovery of deep-water seagrass meadows in a pristine Indian Ocean wilderness revealed by tracking green turtles.

    Science.gov (United States)

    Esteban, N; Unsworth, R K F; Gourlay, J B Q; Hays, G C

    2018-03-21

    Our understanding of global seagrass ecosystems comes largely from regions characterized by human impacts with limited data from habitats defined as notionally pristine. Seagrass assessments also largely focus on shallow-water coastal habitats with comparatively few studies on offshore deep-water seagrasses. We satellite tracked green turtles (Chelonia mydas), which are known to forage on seagrasses, to a remote, pristine deep-water environment in the Western Indian Ocean, the Great Chagos Bank, which lies in the heart of one of the world's largest marine protected areas (MPAs). Subsequently we used in-situ SCUBA and baited video surveys to survey the day-time sites occupied by turtles and discovered extensive monospecific seagrass meadows of Thalassodendron ciliatum. At three sites that extended over 128 km, mean seagrass cover was 74% (mean range 67-88% across the 3 sites at depths to 29 m. The mean species richness of fish in seagrass meadows was 11 species per site (mean range 8-14 across the 3 sites). High fish abundance (e.g. Siganus sutor: mean MaxN.site -1  = 38.0, SD = 53.7, n = 5) and large predatory shark (Carcharhinus amblyrhynchos) (mean MaxN.site -1  = 1.5, SD = 0.4, n = 5) were recorded at all sites. Such observations of seagrass meadows with large top predators, are limited in the literature. Given that the Great Chagos Bank extends over approximately 12,500 km 2 and many other large deep submerged banks exist across the world's oceans, our results suggest that deep-water seagrass may be far more abundant than previously suspected. Copyright © 2018 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  20. Livestock grazing intensity affects abundance of Common shrews (Sorex araneus) in two meadows in Denmark

    DEFF Research Database (Denmark)

    Schmidt, Niels Martin; Olsen, Henrik; Leirs, Herwig

    2009-01-01

    habitat type for a large number of animal species in today's fragmented and intensively cultivated landscape of Europe. Here we focus on the population characteristics of Common shrews Sorex araneus in relation to livestock grazing intensity in two wet meadows in western Denmark. Results: High grazing...... as well as in most other European countries, the amount of land covered by semi-natural grassland has decreased dramatically during the 20th century concurrent with the general intensification of the agricultural production. To reverse this trend, actions are being taken in many places to either maintain...

  1. Lake Roosevelt Fisheries Evaluation Program; Meadow Creek vs. Lake Whatcom Stock Kokanee Salmon Investigations in Lake Roosevelt, Annual Report 2002.

    Energy Technology Data Exchange (ETDEWEB)

    McLellan, Holly

    2003-03-01

    Lake Whatcom, Washington kokanee have been stocked in Lake Roosevelt since 1987 with the primary objective of creating a self-sustaining fishery. Success has been limited by low recruitment to the fishery, low adult returns to hatcheries, and a skewed sex ratio. It was hypothesized that a stock native to the upper Columbia River might perform better than the coastal Lake Whatcom stock. Kokanee from Meadow Creek, a tributary of Kootenay Lake, British Columbia were selected as an alternative stock. Post smolts from each stock were released from Sherman Creek Hatchery in late June 2000 and repeated in 2001. Stock performance was evaluated using three measures; (1) number of returns to Sherman Creek, the primary egg collection facility, (2) the number of returns to 86 tributaries sampled and, (3) the number of returns to the creel. In two repeated experiments, neither Meadow Creek or Lake Whatcom kokanee appeared to be capable of providing a run of three-year old spawners to sustain stocking efforts. Less than 10 three-years olds from either stock were collected during the study period. Chi-square analysis indicated age two Meadow Creek kokanee returned to Sherman Creek and to other tributaries in significantly higher numbers when compared to the Lake Whatcom stock in both 2000 and 2001. However, preliminary data from the Spokane Tribe of Indians indicated that a large number of both stocks were precocial before they were stocked. The small number of hatchery three-year olds collected indicated that the current hatchery rearing and stocking methods will continue to produce a limited jacking run largely composed of precocious males and a small number of three-year olds. No kokanee from the study were collected during standard lake wide creel surveys. Supplemental creel data, including fishing derbies, test fisheries, and angler diaries, indicated anglers harvested two-year-old hatchery kokanee a month after release. The majority of the two-year old kokanee harvested

  2. Distribution and movement of Big Spring spinedace (Lepidomeda mollispinis pratensis) in Condor Canyon, Meadow Valley Wash, Nevada

    Science.gov (United States)

    Jezorek, Ian G.; Connolly, Patrick J.

    2013-01-01

    Big Spring spinedace (Lepidomeda mollispinis pratensis) is a cyprinid whose entire population occurs within a section of Meadow Valley Wash, Nevada. Other spinedace species have suffered population and range declines (one species is extinct). Managers, concerned about the vulnerability of Big Spring spinedace, have considered habitat restoration actions or translocation, but they have lacked data on distribution or habitat use. Our study occurred in an 8.2-km section of Meadow Valley Wash, including about 7.2 km in Condor Canyon and 0.8 km upstream of the canyon. Big Spring spinedace were present upstream of the currently listed critical habitat, including in the tributary Kill Wash. We found no Big Spring spinedace in the lower 3.3 km of Condor Canyon. We tagged Big Spring spinedace ≥70 mm fork length (range 70–103 mm) with passive integrated transponder tags during October 2008 (n = 100) and March 2009 (n = 103) to document movement. At least 47 of these individuals moved from their release location (up to 2 km). Thirty-nine individuals moved to Kill Wash or the confluence area with Meadow Valley Wash. Ninety-three percent of movement occurred in spring 2009. Fish moved both upstream and downstream. We found no movement downstream over a small waterfall at river km 7.9 and recorded only one fish that moved downstream over Delmue Falls (a 12-m drop) at river km 6.1. At the time of tagging, there was no significant difference in fork length or condition between Big Spring Spinedace that were later detected moving and those not detected moving. We found no significant difference in fork length or condition at time of tagging of Big Spring spinedace ≥70 mm fork length that were detected moving and those not detected moving. Kill Wash and its confluence area appeared important to Big Spring spinedace; connectivity with these areas may be key to species persistence. These areas may provide a habitat template for restoration or translocation. The lower 3.3 km of

  3. Evaluating 90Sr and 137Cs accumulation by structural elements of exclusion zone's vegetative communities of meadow and lea land

    International Nuclear Information System (INIS)

    Paskevich, S.A.; Petrov, M.F.

    2003-01-01

    Biogenic carry-over of 90 Sr and 137 Cs by structural elements of exclusion zone's meadows and lea land phytocenosis is considered. Quantitative parameters of radionuclide accumulation are evaluated in substrate and live biomass of communities growing under various ecological conditions. It was stated that accumulation levels for ground biomass of communities depends, at a significant rate, on landscape growing conditions. These values fluctuate within the range of around 100 times. For 90 Sr, significantly lower difference in carry-over values was observed totaling up to 5 times, although for single community, this radionuclide carry-over exceeds essentially 137 Cs carry-over

  4. Dynamics of leaf litter humidity, depth and quantity: two restoration strategies failed to mimic ground microhabitat conditions of a low montane and premontane forest in Costa Rica

    OpenAIRE

    Zaidett Barrientos

    2012-01-01

    Little is known about how restoration strategies affect aspects like leaf litter’s quantity, depth and humidity. I analyzed leaf litter’s quantity, depth and humidity yearly patterns in a primary tropical lower montane wet forest and two restored areas: a 15 year old secondary forest (unassisted restoration) and a 40 year old Cupressus lusitanica plantation (natural understory). The three habitats are located in the Río Macho Forest Reserve, Costa Rica. Twenty litter samples were ...

  5. Combined community ecology and floristics, a synthetic study on the upper montane evergreen broad-leaved forests in Yunnan, southwestern China

    Institute of Scientific and Technical Information of China (English)

    Hua Zhu; Yong Chai; Shisun Zhou; Lichun Yan; Jipu Shi; Guoping Yang

    2016-01-01

    The upper montane evergreen broad-leaved forest in Yunnan occurs mainly in the zone of persistent cloud and has a discontinuous, island-like, distribution. It is diverse, rich in endemic species, and likely to be sensitive to climate change. Six 1-ha sampling plots were established across the main distribution area of the upper montane evergreen broad-leaved forest in Yunnan. All trees with d.b.h.>1 cm in each plot were identified. Patterns of seed plant distributions were quantified at the specific, generic and family levels. The forests are dominated by the families Fagaceae, Lauraceae, Theaceae and Magnoliaceae, but are very diverse with only a few species shared between sites. Floristic similarities at the family and generic level were high, but they were low at the specific level, with species complementarity between plots. Diversity varied greatly among sites, with greater species richness and more rare species in western Yunnan than central Yunnan. The flora is dominated by tropical biogeographical elements, mainly the pantropic and the tropical Asian distributions at the family and genus levels. In contrast, at the species level, the flora is dominated by the southwest or the southeast China distributions, including Yunnan endemics. This suggests that the flora of the upper montane forest in Yunnan could have a tropical floristic origin, and has adapted to cooler temperatures with the uplift of the Himalayas. Due to great sensitivity to climate, high endemism and species complementarity, as well as the discontinuous, island-like, distribution patterns of the upper montane forest in Yunnan, the regional conservation of the forest is especially needed.

  6. Initial shifts in nitrogen impact on ecosystem carbon fluxes in an alpine meadow: patterns and causes

    Directory of Open Access Journals (Sweden)

    B. Song

    2017-09-01

    Full Text Available Increases in nitrogen (N deposition can greatly stimulate ecosystem net carbon (C sequestration through positive N-induced effects on plant productivity. However, how net ecosystem CO2 exchange (NEE and its components respond to different N addition rates remains unclear. Using an N addition gradient experiment (six levels: 0, 2, 4, 8, 16, 32 gN m−2 yr−1 in an alpine meadow on the Qinghai–Tibetan Plateau, we explored the responses of different ecosystem C fluxes to an N addition gradient and revealed mechanisms underlying the dynamic responses. Results showed that NEE, ecosystem respiration (ER, and gross ecosystem production (GEP all increased linearly with N addition rates in the first year of treatment but shifted to N saturation responses in the second year with the highest NEE (−7.77 ± 0.48 µmol m−2 s−1 occurring under an N addition rate of 8 gN m−2 yr−1. The saturation responses of NEE and GEP were caused by N-induced accumulation of standing litter, which limited light availability for plant growth under high N addition. The saturation response of ER was mainly due to an N-induced saturation response of aboveground plant respiration and decreasing soil microbial respiration along the N addition gradient, while decreases in soil microbial respiration under high N addition were caused by N-induced reductions in soil pH. We also found that various components of ER, including aboveground plant respiration, soil respiration, root respiration, and microbial respiration, responded differentially to the N addition gradient. These results reveal temporal dynamics of N impacts and the rapid shift in ecosystem C fluxes from N limitation to N saturation. Our findings bring evidence of short-term initial shifts in responses of ecosystem C fluxes to increases in N deposition, which should be considered when predicting long-term changes in ecosystem net C sequestration.

  7. Cascading effects of predator-detritivore interactions depend on environmental context in a Tibetan alpine meadow.

    Science.gov (United States)

    Wu, Xinwei; Griffin, John N; Sun, Shucun

    2014-05-01

    Studies of grazing food webs show that species traits can interact with environmental factors to determine the strength of trophic cascades, but analogous context dependencies in detrital food webs remain poorly understood. In predator-detritivore-plant interaction chains, predators are expected to indirectly suppress plant biomass by reducing the density of plant-facilitating detritivores. However, this outcome can be reversed where above-ground predators drive burrowing detritivores to lower soil levels, strengthening their plant-facilitating effects. Here, we show that these trait-mediated indirect interactions further depend on environmental context in a Tibetan alpine meadow. In our study system, undulating topography generates higher (dry soil) patches interspersed with lower (wet soil) patches. Because the ability of detritivores to form deep burrows is likely to be limited by oxygen availability in low patches (wet soil), we hypothesized that (i) burrowing detritivores would undergo a vertical habitat shift, allowing them to more effectively avoid predation, in high - but not low - patches, and (ii) this shift would transmit positive effects of predators to plants in high patches by improving conditions in the lower soil layer. We tested these hypotheses using complementary field and glasshouse experiments examining whether the cascading effects of above-ground predatory beetles (presence/absence) on the density and behaviour of tunnel-forming detritivorous beetles, soil properties, and plant growth varied with patch type (low/high). Results revealed that predatory beetles did not reduce the density of detritivores in either patch type but had context-dependent trait-mediated effects, increasing the tunnelling depth of detritivores, improving soil conditions and ultimately increasing plant biomass in the high but not low patches. This study adds to an emerging predictive framework linking predators to plants in detritus food webs, demonstrating that these

  8. Differential response of microbial respiration to supplied nitrogen forms in 3 contrasting alpine meadow soils on the Tibetan Plateau

    Directory of Open Access Journals (Sweden)

    Xiaoyang Zeng

    Full Text Available ABSTRACT An incubation experiment was conducted to examine the effects of nitrogen (N applications in different forms (NH4NO3, NH4Cl, and KNO3 on microbial respiration considering 3 different alpine meadow soils (C poor soil, pH = 8.1, 1.6% C; C moderate soil, pH = 6.0, 5.0% C; C rich soil, pH = 7.1, 7.4% C in the Tibetan Plateau. The addition of NH4NO3 and NH4Cl increased the microbial respiration in C poor soil, but KNO3 had no effect. The inorganic N forms had no effects on C rich soil, but decreased microbial respiration in C moderate soil. Soil microbial respiration levels across the different types were ordered as follows: C poor soil < C rich soil < C moderate soil, regardless of N addition. These results suggest that the effect of N on microbial respiration in alpine meadow soils is more dependent on the initial soil pH than on soil C availability.

  9. Photosynthetic temperature responses of tree species in Rwanda: evidence of pronounced negative effects of high temperature in montane rainforest climax species.

    Science.gov (United States)

    Vårhammar, Angelica; Wallin, Göran; McLean, Christopher M; Dusenge, Mirindi Eric; Medlyn, Belinda E; Hasper, Thomas B; Nsabimana, Donat; Uddling, Johan

    2015-05-01

    The sensitivity of photosynthetic metabolism to temperature has been identified as a key uncertainty for projecting the magnitude of the terrestrial feedback on future climate change. While temperature responses of photosynthetic capacities have been comparatively well investigated in temperate species, the responses of tropical tree species remain unexplored. We compared the responses of seedlings of native cold-adapted tropical montane rainforest tree species with those of exotic warm-adapted plantation species, all growing in an intermediate temperature common garden in Rwanda. Leaf gas exchange responses to carbon dioxide (CO2 ) at different temperatures (20-40°C) were used to assess the temperature responses of biochemical photosynthetic capacities. Analyses revealed a lower optimum temperature for photosynthetic electron transport rates than for Rubisco carboxylation rates, along with lower electron transport optima in the native cold-adapted than in the exotic warm-adapted species. The photosynthetic optimum temperatures were generally exceeded by daytime peak leaf temperatures, in particular in the native montane rainforest climax species. This study thus provides evidence of pronounced negative effects of high temperature in tropical trees and indicates high susceptibility of montane rainforest climax species to future global warming. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  10. Photosynthetic temperature responses of tree species in Rwanda: evidence of pronounced negative effects of high temperature in montane rainforest climax species

    Science.gov (United States)

    Vårhammar, Angelica; Wallin, Göran; McLean, Christopher M.; Dusenge, Mirindi Eric; Medlyn, Belinda E.; Hasper, Thomas B.; Nsabimana, Donat; Uddling, Johan

    2015-04-01

    The sensitivity of photosynthetic metabolism to temperature has been identified as a key uncertainty for projecting the magnitude of the terrestrial feedback on future climate change. While temperature responses of photosynthetic capacities have been comparatively well investigated in temperate species, the responses of tropical tree species remain unexplored. We compared the responses of seedlings of native cold-adapted tropical montane rainforest tree species to exotic warm-adapted plantation species, all growing in an intermediate temperature common garden in Rwanda. Leaf gas exchange responses to CO2 at different temperatures (20 - 40 C) were used to assess the temperature responses of biochemical photosynthetic capacities. Analyses revealed a lower optimum temperature for photosynthetic electron transport rates than for Rubisco carboxylation rates, along with lower electron transport optima in the native cold-adapted than in the exotic warm-adapted species. The photosynthetic optimum temperatures were generally exceeded by daytime peak leaf temperatures, in particular in the native montane rainforest climax species. This study thus provides evidence of pronounced negative effects of high temperature in tropical trees and indicates high susceptibility of montane rainforest climax species to future global warming. (Reference: New Phytologist, in press)

  11. The effect of climate and soil conditions on tree species turnover in a Tropical Montane Cloud Forest in Costa Rica.

    Science.gov (United States)

    Häger, Achim

    2010-12-01

    On a global level, Tropical Montane Cloud Forests constitute important centers of vascular plant diversity. Tree species turnover along environmental gradients plays an important role in larger scale diversity patterns in tropical mountains. This study aims to estimate the magnitude of beta diversity across the Tilardn mountain range in North-Western Costa Rica, and to elucidate the impact of climate and soil conditions on tree species turnover at a local scale. Seven climate stations measuring rainfall, horizontal precipitation (clouds and wind-driven rain) and temperatures were installed along a 2.5km transect ranging from 1200 m.a.s.l. on the Atlantic to 1200 m.a.s.l. on the Pacific slope. The ridge top climate station was located at 1500 m.a.s.l. Climate data were recorded from March through December 2003. Additionally, seven 0.05 ha plots were established. On all plots soil moisture was monitored for one year, furthermore soil type and soil chemistry were assessed. Woody plants with a diameter at breast height (dbh) > or = 5 cm were identified to species. Species' distributions were explored by feeding pairwise Serensen measures between plots into a Principal Component Analysis. Relationships between floristic similarity and environmental variables were analyzed using Mantel tests. Pronounced gradients in horizontal precipitation, temperatures and soil conditions were found across the transect. In total, 483 woody plants were identified, belonging to 132 species. Environmental gradients were paralleled by tree species turnover; the plots could be divided in three distinctive floristic units which reflected different topographic positions on the transect (lower slopes, mid slopes and ridge). Most notably there was a complete species turnover between the ridge and the lower Pacific slope. Floristic similarity was negatively correlated with differences in elevation, horizontal precipitation, temperatures and soil conditions between plots. It is suggested that

  12. Variation in leaf litter production and resorption of nutrients in abundant tree species in Nyungwe tropical montane rainforest in Rwanda

    Science.gov (United States)

    Nyirambangutse, Brigitte; Mirindi Dusenge, Eric; Nsabimana, Donat; Bizuru, Elias; Pleijel, Håkan; Uddling, Johan; Wallin, Göran

    2014-05-01

    African tropical rainforests play many roles from local to global scale as providers of resources and ecosystem services. Although covering 30% of the global rainforest, only few studies aiming to better understand the storage and fluxes of carbon and nutrients in these forests have been conducted. To answer questions related to these issues, we have established 15 permanent 0.5 ha plots where we compare carbon and nutrient fluxes of primary and secondary forest tree communities in a tropical montane forest in central Africa. The studies are conducted in Nyungwe montane tropical rain forest gazetted as a National Park to protect its extensive floral and faunal diversity covering an area of 970 km2. Nyungwe is located in Southwest Rwanda (2o17'-2o50'S, 29o07'-29o26A'E). The forest is ranging between 1600-2950 m.a.s.l. and is one of the most biologically important rainforest in Albertine Rift region in terms of Biodiversity. Nyungwe consists of a mixture of primary and secondary forest communities supporting a richness of plant and animal life. More than 260 species of trees and shrubs have been found in Nyungwe, including species endemic to the Albertine Rift. The forest has a climate with a mean annual temperature of 15.5oC and annual rainfall of ca 1850 mm yr-1, with July and August being the only months when rainfall drops. A part of this study is focusing on the dynamics of nutrients through leaf turnover. This turnover of leaves is regulated to maximize the carbon gain through canopy photosynthesis and resource-use efficiency of the plant. It is known that about half of leaf nitrogen is invested in photosynthetic apparatus and that there normally is a strong correlation between the photosynthetic capacity and leaf nitrogen per unit area. Hence leaf nitrogen is an important factor for canopy photosynthesis. However, leaves are produced, senesce and fall. Some nitrogen in the leaf is lost when leaves senesce but other is resorbed. The resorption of nitrogen

  13. Mapping Spatial Patterns of Posidonia oceanica Meadows by Means of Daedalus ATM Airborne Sensor in the Coastal Area of Civitavecchia (Central Tyrrhenian Sea, Italy

    Directory of Open Access Journals (Sweden)

    Marco Marcelli

    2013-10-01

    Full Text Available The spatial distribution of sea bed covers and seagrass in coastal waters is of key importance in monitoring and managing Mediterranean shallow water environments often subject to both increasing anthropogenic impacts and climate change effects. In this context we present a methodology for effective monitoring and mapping of Posidonia oceanica (PO meadows in turbid waters using remote sensing techniques tested by means of LAI (Leaf Area Index point sea truth measurements. Preliminary results using Daedalus airborne sensor are reported referring to the PO meadows at Civitavecchia site (central Tyrrhenian sea where vessel traffic due to presence of important harbors and huge power plant represent strong impact factors. This coastal area, 100 km far from Rome (Central Italy, is characterized also by significant hydrodynamic variations and other anthropogenic factors that affect the health of seagrass meadows with frequent turbidity and suspended sediments in the water column. During 2011–2012 years point measurements of several parameters related to PO meadows phenology were acquired on various stations distributed along 20 km of coast between the Civitavecchia and S. Marinella sites. The Daedalus airborne sensor multispectral data were preprocessed with the support of satellite (MERIS derived water quality parameters to obtain here improved thematic maps of the local PO distribution. Their thematic accuracy was then evaluated as agreement (R2 with the point sea truth measurements and regressive modeling using an on purpose developd method.

  14. Habitat selection of the pink shrimp Farfantepenaeus paulensis and the blue crab Callinectes sapidus in an estuary in southern Brazil: influence of salinity and submerged seagrass meadows

    Directory of Open Access Journals (Sweden)

    Vinicius Mendes Ruas

    Full Text Available This study was conducted in two estuarine inlets (Saco da Mangueira and Saco do Arraial at the Patos Lagoon estuary, southern Brazil. The changes in relative abundance and size of post-larvae and juvenile shrimp Farfantepenaeus paulensis and juvenile blue crab Callinectes sapidus were compared, considering the influence of salinity and the presence of submerged seagrass meadows. The analyses were performed using generalized linear models (GLM for abundance variations and ANOVA for variations on the size of individuals. The pink shrimp was more abundant at Saco da Mangueira, in seagrass meadows and areas of higher salinity. The blue crab was more abundant at Saco do Arraial and in lower levels of salinity. The importance of submerged vegetation for the blue crab lies in a preference of smaller crabs of the species for the seagrass meadows. It has been shown that these species choose different habitats in the estuary, and both the salinity and the presence of submerged seagrass meadows influence the selection of habitat.

  15. The effect of cellulose crystallinity on the in vitro digestibility and fermentation, kinetics of meadow hay and barley, wheat and rice straws

    NARCIS (Netherlands)

    Cone, J.W.; Gelder, van A.H.; Fonseca, A.; Ferreira, L.M.M.; Sequeria, C.A.

    2003-01-01

    The effect of cellulose crystallinity on in vitro digestibility (IVD) and fermentation kinetics was investigated in samples of meadow hay and barley, wheat and rice straws. A saturated solution of potassium permanganate was used to isolate the celluloses, and their crystallinity was evaluated in a

  16. ARSENIC REMOVAL FROM DRINKING WATER BY ADSORPTIVE MEDIA. U.S. EPA DEMONSTRATION PROJECT AT SOUTH TRUCKEE MEADOWS GENERAL IMPROVEMENT DISTRICT (STMIG), NV. INTERIM EVALUATION REPORT

    Science.gov (United States)

    This report documents the activities performed during and the results obtained from the first 32 weeks of operation of an arsenic and antimony removal technology currently being demonstrated at the South Truckee Meadows General Improvement District (STMGID) in Washoe County, NV. ...

  17. Seed dispersal in agricultural habitats and the restoration of species-rich meadows = Dispersie van zaden in cultuurlandschappen en het herstel van soortenrijke graslanden

    NARCIS (Netherlands)

    Dorp, van D.

    1996-01-01


    The restoration of species-rich meadows on former agricultural land in the Netherlands has a high priority, because these ecosystems have been disappearing rapidly due to eutrophication and acidification and falling water tables. In order to be able to restore such ecosystems on wet

  18. How a regional aquifer, a local aquifer and an oxbow lake impact on hydrological and biogeochemical processes in ariparian fen-meadow ecosystem

    DEFF Research Database (Denmark)

    Hoffmann, Carl Christian; Pedersen, Morten Lauge; Rasmussen, K. R.

    2009-01-01

    The groundwater flow pattern through a riparian fen-meadow was investigated by use of piezometer transects, soil survey, measurements of piezometric heads and measurements of hydraulic conductivity. Groundwater was sampled from piezometers and analysed for nitrate-N. Water balances and nitrate-N ...

  19. Phosphate Release Upon Long- and Short -Term Flooding of Fen Meadows Depends on Land Use History and Soil pH

    NARCIS (Netherlands)

    Beltman, B.; Van Der Ven, P. J. M.; Verhoeven, J. T. A.; Sarneel, J. M.

    2014-01-01

    Flooding of acidified and desiccated fen meadows is a management approach for mitigating loss of plant species as well as a short-term measure to prevent flooding in urban areas. Studies have shown that flooding events can cause extreme P release from soils. We questioned whether the occurrence of

  20. Phosphate release upon short- and long-term flooding of fen meadows depends on land use history and pH.

    NARCIS (Netherlands)

    Beltman, Boudewijn; van der Ven, P.J.M.; Verhoeven, Jos; Sarneel, J

    2014-01-01

    Flooding of acidified and desiccated fen meadows is a management approach for mitigating loss of plant species as well as a short-term measure to prevent flooding in urban areas. Studies have shown that flooding events can cause extreme P release from soils. We questioned whether the occurrence of

  1. Promoting Pollinating Insects in Intensive Agricultural Matrices: Field-Scale Experimental Manipulation of Hay-Meadow Mowing Regimes and Its Effects on Bees

    Science.gov (United States)

    Buri, Pierrick; Humbert, Jean-Yves; Arlettaz, Raphaël

    2014-01-01

    Bees are a key component of biodiversity as they ensure a crucial ecosystem service: pollination. This ecosystem service is nowadays threatened, because bees suffer from agricultural intensification. Yet, bees rarely benefit from the measures established to promote biodiversity in farmland, such as agri-environment schemes (AES). We experimentally tested if the spatio-temporal modification of mowing regimes within extensively managed hay meadows, a widespread AES, can promote bees. We applied a randomized block design, replicated 12 times across the Swiss lowlands, that consisted of three different mowing treatments: 1) first cut not before 15 June (conventional regime for meadows within Swiss AES); 2) first cut not before 15 June, as treatment 1 but with 15% of area left uncut serving as a refuge; 3) first cut not before 15 July. Bees were collected with pan traps, twice during the vegetation season (before and after mowing). Wild bee abundance and species richness significantly increased in meadows where uncut refuges were left, in comparison to meadows without refuges: there was both an immediate (within year) and cumulative (from one year to the following) positive effect of the uncut refuge treatment. An immediate positive effect of delayed mowing was also evidenced in both wild bees and honey bees. Conventional AES could easily accommodate such a simple management prescription that promotes farmland biodiversity and is likely to enhance pollination services. PMID:24416434

  2. Promoting pollinating insects in intensive agricultural matrices: field-scale experimental manipulation of hay-meadow mowing regimes and its effects on bees.

    Science.gov (United States)

    Buri, Pierrick; Humbert, Jean-Yves; Arlettaz, Raphaël

    2014-01-01

    Bees are a key component of biodiversity as they ensure a crucial ecosystem service: pollination. This ecosystem service is nowadays threatened, because bees suffer from agricultural intensification. Yet, bees rarely benefit from the measures established to promote biodiversity in farmland, such as agri-environment schemes (AES). We experimentally tested if the spatio-temporal modification of mowing regimes within extensively managed hay meadows, a widespread AES, can promote bees. We applied a randomized block design, replicated 12 times across the Swiss lowlands, that consisted of three different mowing treatments: 1) first cut not before 15 June (conventional regime for meadows within Swiss AES); 2) first cut not before 15 June, as treatment 1 but with 15% of area left uncut serving as a refuge; 3) first cut not before 15 July. Bees were collected with pan traps, twice during the vegetation season (before and after mowing). Wild bee abundance and species richness significantly increased in meadows where uncut refuges were left, in comparison to meadows without refuges: there was both an immediate (within year) and cumulative (from one year to the following) positive effect of the uncut refuge treatment. An immediate positive effect of delayed mowing was also evidenced in both wild bees and honey bees. Conventional AES could easily accommodate such a simple management prescription that promotes farmland biodiversity and is likely to enhance pollination services.

  3. Promoting pollinating insects in intensive agricultural matrices: field-scale experimental manipulation of hay-meadow mowing regimes and its effects on bees.

    Directory of Open Access Journals (Sweden)

    Pierrick Buri

    Full Text Available Bees are a key component of biodiversity as they ensure a crucial ecosystem service: pollination. This ecosystem service is nowadays threatened, because bees suffer from agricultural intensification. Yet, bees rarely benefit from the measures established to promote biodiversity in farmland, such as agri-environment schemes (AES. We experimentally tested if the spatio-temporal modification of mowing regimes within extensively managed hay meadows, a widespread AES, can promote bees. We applied a randomized block design, replicated 12 times across the Swiss lowlands, that consisted of three different mowing treatments: 1 first cut not before 15 June (conventional regime for meadows within Swiss AES; 2 first cut not before 15 June, as treatment 1 but with 15% of area left uncut serving as a refuge; 3 first cut not before 15 July. Bees were collected with pan traps, twice during the vegetation season (before and after mowing. Wild bee abundance and species richness significantly increased in meadows where uncut refuges were left, in comparison to meadows without refuges: there was both an immediate (within year and cumulative (from one year to the following positive effect of the uncut refuge treatment. An immediate positive effect of delayed mowing was also evidenced in both wild bees and honey bees. Conventional AES could easily accommodate such a simple management prescription that promotes farmland biodiversity and is likely to enhance pollination services.

  4. Photosynthesis and Rubisco kinetics in spring wheat and meadow fescue under conditions of simulated climate change with elevated CO2 and increased temperatures

    Directory of Open Access Journals (Sweden)

    K. HAKALA

    2008-12-01

    Full Text Available Spring wheat (Triticum aestivum L.cv.Polkkaand meadow fescue (Festuca pratensis Hudson cv. Kalevicwere grown in ambient and elevated (700 µl l -1 carbon dioxide concentration both at present ambient temperatures and at temperatures 3°C higher than at present simulating a future climate.The CO2 concentrations were elevated in large (3 m in diameteropen top chambers and the temperatures in a greenhouse built over the experimental field.The photosynthetic rate of both wheat and meadow fescue was 31 –37%higher in elevated carbon dioxide (eCO2 than in ambient CO 2 (aCO2 throughout the growing season.The enhancement in wheat photosynthesis in eCO2 declined 10 –13 days before yellow ripeness,at which point the rate of photosynthesis in both CO 2 treatments declined.The stomatal conductance of wheat and meadow fescue was 23–36% lower in eCO2 than in aCO2 .The amount and activity of ribulose-1,5-bisphosphate carboxylase-oxygenase (Rubisco in wheat were lower under conditions of eCO2 ,except at elevated temperatures in 1993 when there was a clear yield increase.There was no clear change in the amount and activity of Rubisco in meadow fescue under eCO2 at either elevated or ambient temperature.This suggests that adaptation to elevated CO2 at biochemical level occurs only when there is insufficient sink for photosynthetic products.While the sink size of wheat can be increased only by introducing new,more productive genotypes,the sink size of meadow fescue can be regulated by fitting the cutting schedule to growth.;

  5. Caterpillars and host plant records for 59 species of Geometridae (Lepidoptera) from a montane rainforest in southern Ecuador.

    Science.gov (United States)

    Bodner, Florian; Brehm, Gunnar; Homeier, Jürgen; Strutzenberger, Patrick; Fiedler, Konrad

    2010-01-01

    During four months of field surveys at the Reserva Biológica San Francisco in the south Ecuadorian Andes, caterpillars of 59 Geometridae species were collected in a montane rainforest between 1800 and 2800m altitude and reared to adults. The resulting data on host plant affiliations of these species was collated. The preimaginal stages of 58 and adult stages of all 59 species are depicted in colour plates. Observations on morphology and behaviour are briefly described. Five species, documented for the first time in the study area by means of larval collections, had not been previously collected by intensive light-trap surveys. Together with published literature records, life-history data covers 8.6% of the 1271 geometrid species observed so far in the study area. For 50 species these are the first records of their early stages, and for another 7 the data significantly extend known host plant ranges. Most larvae were collected on shrubs or trees, but more unusual host plant affiliations, such as ferns (6 geometrid species) and lichens (3 geometrid species), were also recorded. Thirty-four percent of the caterpillars were infested by wasp or tachinid parasitoids.

  6. Integrating effects of species composition and soil properties to predict shifts in montane forest carbon-water relations.

    Science.gov (United States)

    Maxwell, Toby M; Silva, Lucas C R; Horwath, William R

    2018-05-01

    This study was designed to address a major source of uncertainty pertaining to coupled carbon-water cycles in montane forest ecosystems. The Sierra Nevada of California was used as a model system to investigate connections between the physiological performance of trees and landscape patterns of forest carbon and water use. The intrinsic water-use efficiency (iWUE)-an index of CO 2 fixed per unit of potential water lost via transpiration-of nine dominant species was determined in replicated transects along an ∼1,500-m elevation gradient, spanning a broad range of climatic conditions and soils derived from three different parent materials. Stable isotope ratios of carbon and oxygen measured at the leaf level were combined with field-based and remotely sensed metrics of stand productivity, revealing that variation in iWUE depends primarily on leaf traits (∼24% of the variability), followed by stand productivity (∼16% of the variability), climatic regime (∼13% of the variability), and soil development (∼12% of the variability). Significant interactions between species composition and soil properties proved useful to predict changes in forest carbon-water relations. On the basis of observed shifts in tree species composition, ongoing since the 1950s and intensified in recent years, an increase in water loss through transpiration (ranging from 10 to 60% depending on parent material) is now expected in mixed conifer forests throughout the region. Copyright © 2018 the Author(s). Published by PNAS.

  7. Fog in a marginal agricultural area surrounded by montane Andean cloud forest during El Niño climate

    Science.gov (United States)

    García-Santos, G.

    2010-07-01

    The aim of the present study was to evaluate temporal variations of water inputs, rainfall and fog (cloud water), and its contribution to the water balance in a marginal agricultural area of potato surrounded by tropical montane cloud forest in Colombia. Fog in the air boundary layer was estimated using a cylindrical fog collector. Liquid water content of fog events were evaluated before and during natural climate event of El Niño. Our study shows the temporal variation of these two water inputs in both daily and monthly cycles on Boyacá at 2900 m a.s.l. Rainfall was the most frequently observed atmospheric phenomenon, being present on average 62% of the days per year, whereas fog was 45% of the time. Reflected on the lower frequency, annual amount of fog was 11% of precipitation. However during the anomalous dry climate of El Niño, total amount of rainfall was negligible and the few fog events were the only water source for plant growth. Estimated water crop requirements were higher than the water inputs. The survival of the crops was explained by meteorological conditions during dew and fog events. High relative humidity might have eased the plant’s water stress by decreasing transpiration and temperature in leaves and soil, affecting the water balance and the heat exchange between the atmosphere-land interfaces in the marginal agricultural areas during exceptional dry climate.

  8. Comparative Drought Responses of Quercus ilex L. and Pinus sylvestris L. in a Montane Forest Undergoing a Vegetation Shift

    Directory of Open Access Journals (Sweden)

    David Aguadé

    2015-07-01

    Full Text Available Different functional and structural strategies to cope with water shortage exist both within and across plant communities. The current trend towards increasing drought in many regions could drive some species to their physiological limits of drought tolerance, potentially leading to mortality episodes and vegetation shifts. In this paper, we study the drought responses of Quercus ilex and Pinus sylvestris in a montane Mediterranean forest where the former species is replacing the latter in association with recent episodes of drought-induced mortality. Our aim was to compare the physiological responses to variations in soil water content (SWC and vapor pressure deficit (VPD of the two species when living together in a mixed stand or separately in pure stands, where the canopies of both species are completely exposed to high radiation and VPD. P. sylvestris showed typical isohydric behavior, with greater losses of stomatal conductance with declining SWC and greater reductions of stored non-structural carbohydrates during drought, consistent with carbon starvation being an important factor in the mortality of this species. On the other hand, Q. ilex trees showed a more anisohydric behavior, experiencing more negative water potentials and higher levels of xylem embolism under extreme drought, presumably putting them at higher risk of hydraulic failure. In addition, our results show relatively small changes in the physiological responses of Q. ilex in mixed vs. pure stands, suggesting that the current replacement of P. sylvestris by Q. ilex will continue.

  9. Disturbance Alters the Relative Importance of Topographic and Biogeochemical Controls on Microbial Activity in Temperate Montane Forests

    Directory of Open Access Journals (Sweden)

    Rebecca A. Lybrand

    2018-02-01

    Full Text Available Fire and pathogen-induced tree mortality are the two dominant forms of disturbance in Western U.S. montane forests. We investigated the consequences of both disturbance types on the controls of microbial activity in soils from 56 plots across a topographic gradient one year after the 2012 High Park wildfire in Colorado. Topsoil biogeochemistry, soil CO2 efflux, potential exoenzyme activities, and microbial biomass were quantified in plots that experienced fire disturbance, beetle disturbance, or both fire and beetle disturbance, and in plots where there was no recent evidence of disturbance. Soil CO2 efflux, N-, and P-degrading exoenzyme activities in undisturbed plots were positively correlated with soil moisture, estimated from a topographic wetness index; coefficient of determinations ranged from 0.5 to 0.65. Conversely, the same estimates of microbial activities from fire-disturbed and beetle-disturbed soils showed little correspondence to topographically inferred wetness, but demonstrated mostly negative relationships with soil pH (fire only and mostly positive relationships with DOC/TDN (dissolved organic carbon/total dissolved nitrogen ratios for both disturbance types. The coefficient of determination for regressions of microbial activity with soil pH and DOC/TDN reached 0.8 and 0.63 in fire- and beetle-disturbed forests, respectively. Drivers of soil microbial activity change as a function of disturbance type, suggesting simple mathematical models are insufficient in capturing the impact of disturbance in forests.

  10. Sustainable utilization and conservation of plant biodiversity in montane ecosystems: the western Himalayas as a case study.

    Science.gov (United States)

    Khan, Shujaul Mulk; Page, Sue E; Ahmad, Habib; Harper, David M

    2013-08-01

    Conservation of the unique biodiversity of mountain ecosystems needs trans-disciplinary approaches to succeed in a crowded colloquial world. Geographers, conservationists, ecologists and social scientists have, in the past, had the same conservation goals but have tended to work independently. In this review, the need to integrate different conservation criteria and methodologies is discussed. New criteria are offered for prioritizing species and habitats for conservation in montane ecosystems that combine both ecological and social data. Ecological attributes of plant species, analysed through robust community statistical packages, provide unbiased classifications of species assemblages and environmental biodiversity gradients and yield importance value indices (IVIs). Surveys of local communities' utilization of the vegetation provides use values (UVs). This review suggests a new means of assessing anthropogenic pressure on plant biodiversity at both species and community levels by integrating IVI and UV data sets in a combined analysis. Mountain ecosystems are hot spots for plant conservation efforts because they hold a high overall plant diversity as communities replace each other along altitudinal and climatic gradients, including a high proportion of endemic species. This review contributes an enhanced understanding of (1) plant diversity in mountain ecosystems with special reference to the western Himalayas; (2) ethnobotanical and ecosystem service values of mountain vegetation within the context of anthropogenic impacts; and (3) local and regional plant conservation strategies and priorities.

  11. Foggy days and dry nights determine crown-level water balance in a seasonal tropical Montane cloud forest.

    Science.gov (United States)

    Gotsch, Sybil G; Asbjornsen, Heidi; Holwerda, Friso; Goldsmith, Gregory R; Weintraub, Alexis E; Dawson, Todd E

    2014-01-01

    The ecophysiology of tropical montane cloud forest (TMCF) trees is influenced by crown-level microclimate factors including regular mist/fog water inputs, and large variations in evaporative demand, which in turn can significantly impact water balance. We investigated the effect of such microclimatic factors on canopy ecophysiology and branch-level water balance in the dry season of a seasonal TMCF in Veracruz, Mexico, by quantifying both water inputs (via foliar uptake, FU) and outputs (day- and night-time transpiration, NT). Measurements of sap flow, stomatal conductance, leaf water potential and pressure-volume relations were obtained in Quercus lanceifolia, a canopy-dominant tree species. Our results indicate that FU occurred 34% of the time and led to the recovery of 9% (24 ± 9.1 L) of all the dry-season water transpired from individual branches. Capacity for FU was independently verified for seven additional common tree species. NT accounted for approximately 17% (46 L) of dry-season water loss. There was a strong correlation between FU and the duration of leaf wetness events (fog and/or rain), as well as between NT and the night-time vapour pressure deficit. Our results show the clear importance of fog and NT for the canopy water relations of Q. lanceifolia. © 2013 John Wiley & Sons Ltd.

  12. Effect of Tree-to-Shrub Type Conversion in Lower Montane Forests of the Sierra Nevada (USA) on Streamflow.

    Science.gov (United States)

    Bart, Ryan R; Tague, Christina L; Moritz, Max A

    2016-01-01

    Higher global temperatures and increased levels of disturbance are contributing to greater tree mortality in many forest ecosystems. These same drivers can also limit forest regeneration, leading to vegetation type conversion. For the Sierra Nevada of California, little is known about how type conversion may affect streamflow, a critical source of water supply for urban, agriculture and environmental purposes. In this paper, we examined the effects of tree-to-shrub type conversion, in combination with climate change, on streamflow in two lower montane forest watersheds in the Sierra Nevada. A spatially distributed ecohydrologic model was used to simulate changes in streamflow, evaporation, and transpiration following type conversion, with an explicit focus on the role of vegetation size and aspect. Model results indicated that streamflow may show negligible change or small decreases following type conversion when the difference between tree and shrub leaf areas is small, partly due to the higher stomatal conductivity and the deep rooting depth of shrubs. In contrast, streamflow may increase when post-conversion shrubs have a small leaf area relative to trees. Model estimates also suggested that vegetation change could have a greater impact on streamflow magnitude than the direct hydrologic impacts of increased temperatures. Temperature increases, however, may have a greater impact on streamflow timing. Tree-to-shrub type conversion increased streamflow only marginally during dry years (annual precipitation importance of accounting for changes in vegetation communities to accurately characterize future hydrologic regimes for the Sierra Nevada.

  13. Status and limiting factors of two rare plant species in dry montane communities of Hawai`i Volcanoes National Park.

    Science.gov (United States)

    Pratt, Linda W.; VanDeMark, Joshua R.; Euaparadorn, Melody

    2012-01-01

    Two rare plants native to montane dry forests and woodland communities of Hawai`i Volcanoes National Park (HAVO) were studied for more than two years to determine their stand structure, short-term mortality rates, patterns of reproductive phenology, success of fruit production, floral visitor composition, seed germination rates in the greenhouse, and survival of both natural and planted seedlings. Phyllostegia stachyoides, a shrubby Hawaiian mint (Lamiaceae) that is a species of concern, was studied within two small kīpuka at a natural population on the park’s Mauna Loa Strip, and three plantings at sites along the Mauna Loa Road were also monitored. Silene hawaiiensis, a threatened shrub species in the pink family (Caryophyllaceae), was monitored at two natural populations, one on Mauna Loa at the Three Trees Kīpuka and the second on Kīlauea Crater Rim south of Halema`uma`u. Silene hawaiiensis plantings were also made inside and outside ungulate exclosures at the park’s Kahuku Unit

  14. Environmental and physiological influences to isotopic ratios of N and protein status in a montane ungulate in winter

    Science.gov (United States)

    Gustine, David D.; Barboza, Perry S.; Adams, Layne G.; Wolf, Nathan B.

    2014-01-01

    Winter severity can influence large herbivore populations through a reduction in maternal proteins available for reproduction. Nitrogen (N) isotopes in blood fractions can be used to track the use of body proteins in northern and montane ungulates. We studied 113 adult female caribou for 13 years throughout a series of severe winters that reduced population size and offspring mass. After these severe winters, offspring mass increased but the size of the population remained low. We devised a conceptual model for routing of isotopic N in blood in the context of the severe environmental conditions experienced by this population. We measured δ15N in three blood fractions and predicted the relative mobilization of dietary and body proteins. The δ15N of the body protein pool varied by 4‰ and 46% of the variance was associated with year. Annual variation in δ15N of body protein likely reflected the fall/early winter diet and winter locations, yet 15% of the isotopic variation in amino acid N was due to body proteins. Consistent isotopic differences among blood N pools indicated that animals tolerated fluxes in diet and body stores. Conservation of body protein in caribou is the result of active exchange among diet and body N pools. Adult females were robust to historically severe winter conditions and prioritized body condition and survival over early investment in offspring. For a vagile ungulate residing at low densities in a predator-rich environment, protein restrictions in winter may not be the primary limiting factor for reproduction.

  15. Trap-Nesting Bees in Montane Grassland (Campo Rupestre) and Cerrado in Brazil: Collecting Generalist or Specialist Nesters.

    Science.gov (United States)

    Araújo, P C S; Lourenço, A P; Raw, A

    2016-10-01

    Species richness and seasonal abundance of solitary bees were investigated in rocky, montane grassland (campo rupestre) (1180 m asl) and cerrado sensu stricto (680 m asl) in the Biribiri State Park, Diamantina, state of Minas Gerais, Brazil. Three hundred nineteen nest traps of bamboo canes and black cardboard tubes were monthly inspected at each site during 15 months. A total of eight species of bees built 97 nests. Four species were common to both sites. Tetrapedia aff. curvitarsis Friese and Tetrapedia aff. peckoltii Friese were the most abundant at campo rupestre and cerrado s.s., respectively, followed by Centris analis (Fabricius) in campo rupestre and Centris tarsata Smith in cerrado s.s. The nesting peaks occurred in May in campo rupestre and in February in cerrado s.s. Three cuckoo bees and one bee-fly were collected as natural enemies. The findings suggest that differences between the sites were related more to ecological factors (floral resources, natural nest sites) than to the altitudinal difference. The species richness was similar to that in other habitats with open vegetation. We demonstrate the need to use several types of trap-nest to increase the range of species sampled; some species used only one of the two types traps provided. We also comment on the limitations of trap-nests in cerrado vegetation. Most cerrado species of bees are very selective in their choice for a nesting site, but bees that use trap-nests are more generalists.

  16. Methylobacillus pratensis sp. nov., a novel non-pigmented, aerobic, obligately methylotrophic bacterium isolated from meadow grass.

    Science.gov (United States)

    Doronina, Nina V; Trotsenko, Yuri A; Kolganova, Tatjana V; Tourova, Tatjana P; Salkinoja-Salonen, Mirja S

    2004-09-01

    Strain F31T was isolated from meadow grass (Poa trivialis L.) sampled from the city park in Helsinki. Analysis of phenotypic and genotypic properties showed the strain to be related to the group of obligately methylotrophic non-methane utilizing bacteria (methylobacteria) with the ribulose monophosphate pathway of formaldehyde assimilation. Phylogenetic analysis showed the strain to be closely related to the genus Methylobacillus, and analysis of fatty acid composition confirmed this association. Thus, on the basis of its genotypic and phenotypic properties, the isolate is proposed as a novel species of the genus Methylobacillus, Methylobacillus pratensis sp. nov., with F31T as the type strain (= VKM B-2247T = NCIMB 13994T).

  17. Micrometeorological measurements at Ash Meadows and Corn Creek Springs, Nye and Clark counties, Nevada, 1986-87

    Science.gov (United States)

    Johnson, M.J.; Pupacko, Alex

    1992-01-01

    Micrometeorological data were collected at Ash Meadows and Corn Creek Springs, Nye and Clark Counties, Nevada, from October 1, 1986 through September 30, 1987. The data include accumulated measurements recorded hourly or every 30 minutes, at each site, for the following climatic variables: air temperature, wind speed, relative humidity, precipitation, solar radiation, net radiation, and soil-heat flux. Periodic sampling of sensible-heat flux and latent-heat flux were also recorded using 5-minute intervals of accumulated data. Evapotranspiration was calculated by both the eddy-correlation method and the Penman combination method. The data collected and the computer programs used to process the data are available separately on three magnetic diskettes in card-image format. (USGS)

  18. Insect emergence in relation to floods in wet meadows and swamps in the River Dalälven floodplain.

    Science.gov (United States)

    Vinnersten, T Z Persson; Östman, Ö; Schäfer, M L; Lundström, J O

    2014-08-01

    Annual variation in flood frequency and hydroperiod during the vegetation season has ecological impacts on the floodplain biota. Although many insect groups may have a lower emergence during a flood event, it is poorly known how annual emergence of insects in temporary wetlands is related to the variation in hydrology. Between May and September, we studied the weekly emergence of 18 insect taxa over six consecutive years, 2002-2007, in six temporary flooded wetlands (four wet meadows and two forest swamps) in the River Dalälven floodplains, Central Sweden. We used emergence traps to collect emerging insects from terrestrial and aquatic parts of wet meadows and swamp forests. In all wetlands, the insect fauna was numerically dominated by the orders Diptera, Hymenoptera, Coleoptera and Homoptera. On a weekly basis, 9 out of the 18 insect taxa had lower emergence in weeks with flood than in weeks with no flood, whereas no taxon had a higher emergence in weeks with flood. Over the seasons, we related insect emergence to seasonal flood frequency and length of hydroperiod. The emergence of most studied taxa decreased with increasing hydroperiod, which suggests that emergence after floods do not compensate for the reduced emergence during floods. Only Culicidae and the aquatic Chironomidae sub-families Tanypodinae and Chironominae showed an increase in emergence with increasing hydroperiod, whereas Staphylinidae peaked at intermediate hydroperiod. We conclude that a hydroperiod covering up to 40% of the vegetation season has a significant negative effect on the emergence of most taxa and that only a few taxa occurring in the temporary wetlands are actually favoured by a flood regime with recurrent and unpredictable floods.

  19. Plant structure predicts leaf litter capture in the tropical montane bromeliad Tillandsia turneri

    Directory of Open Access Journals (Sweden)

    F. Ospina-Bautista

    Full Text Available Abstract Leaves intercepted by bromeliads become an important energy and matter resource for invertebrate communities, bacteria, fungi, and the plant itself. The relationship between bromeliad structure, defined as its size and complexity, and accumulated leaf litter was studied in 55 bromeliads of Tillandsia turneri through multiple regression and the Akaike information criterion. Leaf litter accumulation in bromeliads was best explained by size and complexity variables such as plant cover, sheath length, and leaf number. In conclusion, plant structure determines the amount of litter that enters bromeliads, and changes in its structure could affect important processes within ecosystem functioning or species richness.

  20. Plant structure predicts leaf litter capture in the tropical montane bromeliad Tillandsia turneri.

    Science.gov (United States)

    Ospina-Bautista, F; Estévez Varón, J V

    2016-05-03

    Leaves intercepted by bromeliads become an important energy and matter resource for invertebrate communities, bacteria, fungi, and the plant itself. The relationship between bromeliad structure, defined as its size and complexity, and accumulated leaf litter was studied in 55 bromeliads of Tillandsia turneri through multiple regression and the Akaike information criterion. Leaf litter accumulation in bromeliads was best explained by size and complexity variables such as plant cover, sheath length, and leaf number. In conclusion, plant structure determines the amount of litter that enters bromeliads, and changes in its structure could affect important processes within ecosystem functioning or species richness.

  1. Twenty-three years of vegetation change in a fly-ash leachate impacted meadow

    Science.gov (United States)

    Pavlovic, Noel B.; Leicht-Young, Stacey A.; Wilcox, Douglas; Hiebert, Ron; Murphy, Marilyn K.; Mason, Daniel; Frohnapple, Krystal

    2009-01-01

    because this transect had the deepest surface water. 5. Typical late successional vegetation associations developed since 1991 include blue joint grass (Calamagrostis canadensis) and buttonbush (Cephalanthus occidentalis), but large areas consist of disturbance-dependent mosaics of rush (Juncus effusus) and other species. The large expanses of woolly sedge (Scirpus cyperinus) that dominated in the 1980’s was replaced by rush. 6. Late-successional associations (Glyceria canadensis and Calamagrostis canadensis) were closer to the wetland edge compared to the other associations after the dewatering. This pattern occurred because wet meadow vegetation persisted at the wetland edge during the period of industrial flooding, but since then these associations expanded greatly into the north half of Blag Slough. 7. Richness, diversity, and floristic quality index (FQI) increased with time at the plot, association, association trajectories, and wetland levels; whereas mean conservatism scores (mean C), the basis of FQI calculation, decreased in time. The high C values, assigned to coastal plain disjunct species and shrubs by judgment of botanists based on their empirical xii experience including regional or state level plant conservation designations are largely responsible for the contradicted trend between FQI and C. Such contradiction highlights a problem with the subjective assignment of C values, and thus the inadequacy of application of FQI in these wetland systems. 8. Occurrence of interveinal clearing in winged sumac (Rhus copallina), late boneset (Eupatorium serotinum), and black dewberry (Rubus occidentalis) suggest a potential phytotoxicity by heavy metals. However, cause-effect relationship between the metals and the plants are yet to be investigated. Nevertheless, boron and zinc accumulation ratios in leaves of woody plants (Betula populifolia, Populus tremuloides, Rhus copallina, and Rubus sp.) in 1984 suggest that boron and zinc were bioaccumulating in those

  2. Assessment of variations in taxonomic diversity, forest structure, and aboveground biomass using remote sensing along an altitudinal gradient in tropical montane forest of Costa Rica

    Science.gov (United States)

    Robinson, C. M.; Saatchi, S. S.; Clark, D.; Fricker, G. A.; Wolf, J.; Gillespie, T. W.; Rovzar, C. M.; Andelman, S.

    2012-12-01

    This research sought to understand how alpha and beta diversity of plants vary and relate to the three-dimensional vegetation structure and aboveground biomass along environmental gradients in the tropical montane forests of Braulio Carrillo National Park in Costa Rica. There is growing evidence that ecosystem structure plays an important role in defining patterns of species diversity and along with abiotic factors (climate and edaphic) control the phenotypic and functional variations across landscapes. It is well documented that strong subdivisions at local and regional scales are found mainly on geologic or climate gradients. These general determinants of biodiversity are best demonstrated in regions with natural gradients such as tropical montane forests. Altitudinal gradients provide a landscape scale changes through variations in topography, climate, and edaphic conditions on which we tested several theoretical and biological hypotheses regarding drivers of biodiversity. The study was performed by using forest inventory and botanical data from nine 1-ha plots ranging from 100 m to 2800 m above sea level and remote sensing data from airborne lidar and radar sensors to quantify variations in forest structure. In this study we report on the effectiveness of relating patterns of tree taxonomic alpha diversity to three-dimensional structure of a tropical montane forest using lidar and radar observations of forest structure and biomass. We assessed alpha and beta diversity at the species, genus, and family levels utilizing datasets provided by the Terrestrial Ecology Assessment and Monitoring (TEAM) Network. Through the comparison to active remote sensing imagery, our results show that there is a strong relationship between forest 3D-structure, and alpha and beta diversity controlled by variations in abiotic factors along the altitudinal gradient. Using spatial analysis with the aid of remote sensing data, we find distinct patterns along the environmental gradients

  3. Root hydraulic vulnerability regulation of whole-plant conductance along hillslope gradients within subalpine and montane forests

    Science.gov (United States)

    Beverly, D.; Speckman, H. N.; Ewers, B. E.

    2017-12-01

    Ecosystem-scale models often rely on root vulnerability or whole-plant conductance for simulating seasonal evapotranspiration declines via constraints of water uptake and vegetation mortality. Further, many of these ecosystem models rely on single, unvarying, hydraulic parameter estimates for modeling large areas. Ring-porous species have shown seasonal variability in root vulnerability (percent loss of conductivity; PLC) and whole-plant conductance (Kw) but simulations of coniferous forest typically rely on point measurements. This assumption for coniferous forest is not likely true because of seasonal variability caused by phenology and environmental stresses and the potential for cavitation fatigue is not considered. Moreover, many of these dynamics have only been considered for stems even though roots are often the most vulnerable segments of the pathway for conifers. We hypothesized that seasonally dynamic whole-plant conductance along hillslope gradients in coniferous forests are regulated by cavitation fatigue within the roots resulting in seasonal increases in vulnerability. To test the hypothesis, a subalpine mixed forest (3000 m.a.s.l) and montane forest (2550 m.a.s.l.) were monitored between 2015-2017 to quantify PLC and Kw along the hillslope gradients of 300 m and 50 m, respectively. Forest plots were instrumented with 35 Granier-type sapflow sensors. Seasonal sampling campaigns occurred to quantify PLC through centrifuge techniques and Kw through Darcy's law approximations with pre-dawn and diurnal leaf water potentials. Downslope roots exhibit a 33% decrease in maximal conductivity corresponding to the approximately 50% decrease in whole-plant conductance suggesting seasonal soil dry-down limitations within the downslope stands. Upslope stands had no to little change in root vulnerability or decrease in whole-plant conductance as soil water limitations occur immediately following snowmelt, thus limiting hydraulic conductance throughout the growing

  4. Water relations and gas exchange of fan bryophytes and their adaptations to microhabitats in an Asian subtropical montane cloud forest.

    Science.gov (United States)

    Song, Liang; Zhang, Yong-Jiang; Chen, Xi; Li, Su; Lu, Hua-Zheng; Wu, Chuan-Sheng; Tan, Zheng-Hong; Liu, Wen-Yao; Shi, Xian-Meng

    2015-07-01

    Fan life forms are bryophytes with shoots rising from vertical substratum that branch repeatedly in the horizontal plane to form flattened photosynthetic surfaces, which are well suited for intercepting water from moving air. However, detailed water relations, gas exchange characteristics of fan bryophytes and their adaptations to particular microhabitats remain poorly understood. In this study, we measured and analyzed microclimatic data, as well as water release curves, pressure-volume relationships and photosynthetic water and light response curves for three common fan bryophytes in an Asian subtropical montane cloud forest (SMCF). Results demonstrate high relative humidity but low light levels and temperatures in the understory, and a strong effect of fog on water availability for bryophytes in the SMCF. The facts that fan bryophytes in dry air lose most of their free water within 1 h, and a strong dependence of net photosynthesis rates on water content, imply that the transition from a hydrated, photosynthetically active state to a dry, inactive state is rapid. In addition, fan bryophytes developed relatively high cell wall elasticity and the osmoregulatory capacity to tolerate desiccation. These fan bryophytes had low light saturation and compensation point of photosynthesis, indicating shade tolerance. It is likely that fan bryophytes can flourish on tree trunks in the SMCF because of substantial annual precipitation, average relative humidity, and frequent and persistent fog, which can provide continual water sources for them to intercept. Nevertheless, the low water retention capacity and strong dependence of net photosynthesis on water content of fan bryophytes indicate a high risk of unbalanced carbon budget if the frequency and severity of drought increase in the future as predicted.

  5. Transpiration of montane Pinus sylvestris L. and Quercus pubescens Willd. forest stands measured with sap flow sensors in NE Spain

    Directory of Open Access Journals (Sweden)

    R. Poyatos

    2005-01-01

    Full Text Available Stand transpiration was measured during the 2003 and 2004 growing seasons using heat dissipation sap flow sensors in a Scots pine (Pinus sylvestris L. and a pubescent oak (Quercus pubescens Willd. forests located in a montane area of the Eastern Pyrenees (NE Spain. The first aim of the study was to assess the differences in quantitative estimates of transpiration (Ec and the response to evaporative demand of the two stands. Over the studied period of 2003, characterised by a severe drought episode during the summer, the oak stand (Ec was only 110 mm compared to the 239 mm transpired by the Scots pine stand, although the ratio of transpiration to reference evapotranspiration (Ec/ET0 in the oak stand compares well with the expected values predicted for low leaf area index (LAI oak forests in southern Europe. Scots pine showed a strong reduction in (Ec/ET0 as the drought developed, whereas pubescent oak was less affected by soil moisture deficits in the upper soil. As a second objective, and given the contrasting meteorological conditions between 2003 and 2004 summer periods, the interannual variability of transpiration was studied in the Scots pine plot. Rainfall during the summer months (June-September in 2003 was almost 40% less than in the same interval in 2004. Accordingly, transpiration was also reduced about 25% in 2003. Finally, Scots pine data from 2003 and 2004 was used to calibrate a simple transpiration model using ET0 and soil moisture deficit (SMD as input variables, and implicitly including stomatal responses to high vapour pressure deficits (Dd and soil water status.

  6. The Relative Impact of Climate Change on the Extinction Risk of Tree Species in the Montane Tropical Andes.

    Science.gov (United States)

    Tejedor Garavito, Natalia; Newton, Adrian C; Golicher, Duncan; Oldfield, Sara

    2015-01-01

    There are widespread concerns that anthropogenic climate change will become a major cause of global biodiversity loss. However, the potential impact of climate change on the extinction risk of species remains poorly understood, particularly in comparison to other current threats. The objective of this research was to examine the relative impact of climate change on extinction risk of upper montane tree species in the tropical Andes, an area of high biodiversity value that is particularly vulnerable to climate change impacts. The extinction risk of 129 tree species endemic to the region was evaluated according to the IUCN Red List criteria, both with and without the potential impacts of climate change. Evaluations were supported by development of species distribution models, using three methods (generalized additive models, recursive partitioning, and support vector machines), all of which produced similarly high AUC values when averaged across all species evaluated (0.82, 0.86, and 0.88, respectively). Inclusion of climate change increased the risk of extinction of 18-20% of the tree species evaluated, depending on the climate scenario. The relative impact of climate change was further illustrated by calculating the Red List Index, an indicator that shows changes in the overall extinction risk of sets of species over time. A 15% decline in the Red List Index was obtained when climate change was included in this evaluation. While these results suggest that climate change represents a significant threat to tree species in the tropical Andes, they contradict previous suggestions that climate change will become the most important cause of biodiversity loss in coming decades. Conservation strategies should therefore focus on addressing the multiple threatening processes currently affecting biodiversity, rather than focusing primarily on potential climate change impacts.

  7. Modeling Aspect Controlled Formation of Seasonally Frozen Ground on Montane Hillslopes: a Case Study from Gordon Gulch, Colorado

    Science.gov (United States)

    Rush, M.; Rajaram, H.; Anderson, R. S.; Anderson, S. P.

    2017-12-01

    The Intergovernmental Panel on Climate Change (2013) warns that high-elevation ecosystems are extremely vulnerable to climate change due to short growing seasons, thin soils, sparse vegetation, melting glaciers, and thawing permafrost. Many permafrost-free regions experience seasonally frozen ground. The spatial distribution of frozen soil exerts a strong control on subsurface flow and transport processes by reducing soil permeability and impeding infiltration. Accordingly, evolution of the extent and duration of frozen ground may alter streamflow seasonality, groundwater flow paths, and subsurface storage, presenting a need for coupled thermal-hydrologic models to project hydrologic responses to climate warming in high-elevation regions. To be useful as predictive tools, such models should incorporate the heterogeneity of solar insolation, vegetation, and snowpack dynamics. We present a coupled thermal-hydrologic modeling study against the backdrop of field observations from Gordon Gulch, a seasonally snow-covered montane catchment in the Colorado Front Range in the Boulder Creek Critical Zone Observatory. The field site features two instrumented hillslopes with opposing aspects: the snowpack on the north-facing slope persists throughout much of the winter season, while the snowpack on the south-facing slope is highly ephemeral. We implemented a surface energy balance and snowpack accumulation and ablation model that is coupled to the subsurface flow and transport code PFLOTRAN-ICE to predict the hydrologic consequences of aspect-controlled frozen soil formation during water years 2013-2016. Preliminary model results demonstrate the occurrence of seasonally-frozen ground on the north-facing slope that directs snowmelt to the stream by way of shallow subsurface flow paths. The absence of persistently frozen ground on the south-facing slope allows deeper infiltration of snowmelt recharge. The differences in subsurface flow paths also suggest strong aspect

  8. Effect of canopy position on germination and seedling survival of epiphytic bromeliads in a Mexican humid montane forest.

    Science.gov (United States)

    Winkler, Manuela; Hülber, Karl; Hietz, Peter

    2005-05-01

    Seeds of epiphytes must land on branches with suitable substrates and microclimates to germinate and for the resulting seedlings to survive. It is important to understand the fate of seeds and seedlings in order to model populations, but this is often neglected when only established plants are included in analyses. The seeds of five bromeliad species were exposed to different canopy positions in a Mexican montane forest, and germination and early seedling survival were recorded. Additionally, the survival of naturally dispersed seedlings was monitored in a census over 2.5 years. Survival analysis, a procedure rarely used in plant ecology, was used to study the influence of branch characteristics and light on germination and seedling survival in natural and experimental populations. Experimental germination percentages ranged from 7.2 % in Tillandsia deppeana to 33.7 % in T. juncea, but the seeds of T. multicaulis largely failed to germinate. Twenty months after exposure between 3.5 and 9.4 % of the seedlings were still alive. There was no evidence that canopy position affected the probability of germination, but time to germination was shorter in less exposed canopy positions indicating that higher humidity accelerates germination. More experimental seedlings survived when canopy openness was high, whereas survival in census-seedlings was influenced by moss cover. While mortality decreased steadily with age in juveniles of the atmospheric Tillandsia, in the more mesomorphic Catopsis sessiliflora mortality increased dramatically in the dry season. Seedling mortality, rather than the failure to germinate, accounts for the differential distribution of epiphytes within the canopy studied. With few safe sites to germinate and high seedling mortality, changes of local climate may affect epiphyte populations primarily through their seedling stage.

  9. Forest structure, stand composition, and climate-growth response in montane forests of Jiuzhaigou National Nature Reserve, China.

    Directory of Open Access Journals (Sweden)

    Mark W Schwartz

    Full Text Available Montane forests of western China provide an opportunity to establish baseline studies for climate change. The region is being impacted by climate change, air pollution, and significant human impacts from tourism. We analyzed forest stand structure and climate-growth relationships from Jiuzhaigou National Nature Reserve in northwestern Sichuan province, along the eastern edge of the Tibetan plateau. We conducted a survey to characterize forest stand diversity and structure in plots occurring between 2050 and 3350 m in elevation. We also evaluated seedling and sapling recruitment and tree-ring data from four conifer species to assess: 1 whether the forest appears in transition toward increased hardwood composition; 2 if conifers appear stressed by recent climate change relative to hardwoods; and 3 how growth of four dominant species responds to recent climate. Our study is complicated by clear evidence of 20(th century timber extraction. Focusing on regions lacking evidence of logging, we found a diverse suite of conifers (Pinus, Abies, Juniperus, Picea, and Larix strongly dominate the forest overstory. We found population size structures for most conifer tree species to be consistent with self-replacement and not providing evidence of shifting composition toward hardwoods. Climate-growth analyses indicate increased growth with cool temperatures in summer and fall. Warmer temperatures during the growing season could negatively impact conifer growth, indicating possible seasonal climate water deficit as a constraint on growth. In contrast, however, we found little relationship to seasonal precipitation. Projected warming does not yet have a discernible signal on trends in tree growth rates, but slower growth with warmer growing season climates suggests reduced potential future forest growth.

  10. Effect of Tree-to-Shrub Type Conversion in Lower Montane Forests of the Sierra Nevada (USA on Streamflow.

    Directory of Open Access Journals (Sweden)

    Ryan R Bart

    Full Text Available Higher global temperatures and increased levels of disturbance are contributing to greater tree mortality in many forest ecosystems. These same drivers can also limit forest regeneration, leading to vegetation type conversion. For the Sierra Nevada of California, little is known about how type conversion may affect streamflow, a critical source of water supply for urban, agriculture and environmental purposes. In this paper, we examined the effects of tree-to-shrub type conversion, in combination with climate change, on streamflow in two lower montane forest watersheds in the Sierra Nevada. A spatially distributed ecohydrologic model was used to simulate changes in streamflow, evaporation, and transpiration following type conversion, with an explicit focus on the role of vegetation size and aspect. Model results indicated that streamflow may show negligible change or small decreases following type conversion when the difference between tree and shrub leaf areas is small, partly due to the higher stomatal conductivity and the deep rooting depth of shrubs. In contrast, streamflow may increase when post-conversion shrubs have a small leaf area relative to trees. Model estimates also suggested that vegetation change could have a greater impact on streamflow magnitude than the direct hydrologic impacts of increased temperatures. Temperature increases, however, may have a greater impact on streamflow timing. Tree-to-shrub type conversion increased streamflow only marginally during dry years (annual precipitation < 800 mm, with most streamflow change observed during wetter years. These modeling results underscore the importance of accounting for changes in vegetation communities to accurately characterize future hydrologic regimes for the Sierra Nevada.

  11. Effect of Tree-to-Shrub Type Conversion in Lower Montane Forests of the Sierra Nevada (USA) on Streamflow

    Science.gov (United States)

    Tague, Christina L.; Moritz, Max A.

    2016-01-01

    Higher global temperatures and increased levels of disturbance are contributing to greater tree mortality in many forest ecosystems. These same drivers can also limit forest regeneration, leading to vegetation type conversion. For the Sierra Nevada of California, little is known about how type conversion may affect streamflow, a critical source of water supply for urban, agriculture and environmental purposes. In this paper, we examined the effects of tree-to-shrub type conversion, in combination with climate change, on streamflow in two lower montane forest watersheds in the Sierra Nevada. A spatially distributed ecohydrologic model was used to simulate changes in streamflow, evaporation, and transpiration following type conversion, with an explicit focus on the role of vegetation size and aspect. Model results indicated that streamflow may show negligible change or small decreases following type conversion when the difference between tree and shrub leaf areas is small, partly due to the higher stomatal conductivity and the deep rooting depth of shrubs. In contrast, streamflow may increase when post-conversion shrubs have a small leaf area relative to trees. Model estimates also suggested that vegetation change could have a greater impact on streamflow magnitude than the direct hydrologic impacts of increased temperatures. Temperature increases, however, may have a greater impact on streamflow timing. Tree-to-shrub type conversion increased streamflow only marginally during dry years (annual precipitation < 800 mm), with most streamflow change observed during wetter years. These modeling results underscore the importance of accounting for changes in vegetation communities to accurately characterize future hydrologic regimes for the Sierra Nevada. PMID:27575592

  12. Soil Organic Carbon Storage and Stability in the Aspen-Conifer Ecotone in Montane Forests in Utah, USA

    Directory of Open Access Journals (Sweden)

    Mercedes Román Dobarco

    2014-04-01

    Full Text Available To assess the potential impact of conifer encroachment on soil organic carbon (SOC dynamics and storage in montane aspen-conifer forests from the interior western US, we sampled mineral soils (0–15 cm across the aspen-conifer ecotones in southern and northern Utah and quantified total SOC stocks, stable SOC (i.e., mineral-associated SOC (MoM, labile SOC (i.e., light fraction (LF, decomposable (CO2 release during long-term aerobic incubations and soluble SOC (hot water extractable organic carbon (HWEOC. Total SOC storage (47.0 ± 16.5 Mg C ha−1 and labile SOC as LF (14.0 ± 7.10 Mg C ha−1, SOC decomposability (cumulative released CO2-C of 5.6 ± 3.8 g C g−1 soil or HWEOC (0.6 ± 0.6 mg C g−1 soil did not differ substantially with vegetation type, although a slight increase in HWEOC was observed with increasing conifer in the overstory. There were statistically significant differences (p = 0.035 in stable MoM storage, which was higher under aspen (31.2 ± 15.1 Mg C ha−1 than under conifer (22.8 ± 9.0 Mg C ha−1, with intermediate values under mixed (25.7 ± 8.8 Mg C ha−1. Texture had the greatest impact on SOC distribution among labile and stable fractions, with increasing stabilization in MoM and decreasing bio-availability of SOC with increasing silt + clay content. Only at lower silt + clay contents (40%–70% could we discern the influence of vegetation on MoM content. This highlights the importance of chemical protection mechanisms for long-term C sequestration.

  13. [Aboveground biomass and nutrient distribution patterns of larch plantation in a montane region of eastern Liaoning Province, China].

    Science.gov (United States)

    Yan, Tao; Zhu, Jiao-Jun; Yang, Kai; Yu, Li-Zhong

    2014-10-01

    Larch is the main timber species of forest plantations in North China. Imbalance in nutrient cycling in soil emerged due to single species composition and mono system structure of plantation. Thus it is necessary to grasp its biomass and nutrients allocation for scientific management and nutrient cycling studies of larch plantation. We measured aboveground biomass (stem, branch, bark and leaf) and nutrient concentrations (C, N, P, K, Ca, Mg, Fe, Mn, Cu and Zn), and analyzed the patterns of accumulation and distribution of 19-year-old larch plantation with diameter at breast height of 12. 8 cm, tree height of 15. 3 m, and density of 2308 trees · hm(-2), in a montane region of eastern Liaoning Province, China. The results showed that aboveground biomass values were 70.26 kg and 162.16 t · hm(-2) for the individual tree of larch and the stand, respectively. There was a significant difference between biomass of the organs, and decreased in the order of stem > branch > bark > leaf. Nutrient accumulation was 749.94 g and 1730.86 kg · hm(-2) for the individual tree of larch and the stand, respectively. Nutrient accumulation of stem was significantly higher than that of branch, bark and leaf, whether it was macro-nutrient or micro-nutrient. Averagely, 749.94 g nutrient elements would be removed from the system when a 19-year-old larch tree was harvested. If only the stem part was removed from the system, the removal of nutrient elements could be reduced by 40.7%.

  14. Complex controls on nitrous oxide flux across a large-elevation gradient in the tropical Peruvian Andes

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    T. Diem

    2017-11-01

    , respectively. This corresponds to weighted annual fluxes of 0.52 ± 0.27 kg N2O–N ha−1 yr−1, 0.05 ± 0.06 kg N2O–N ha−1 yr−1, and 0.04 ± 0.07 kg N2O–N ha−1 yr−1, respectively. Nitrous oxide flux showed weak seasonal variation across the region; only lower montane forest showed significantly higher N2O flux during the dry season compared to wet season. Manipulation of soil moisture content in the laboratory indicated that N2O flux was significantly influenced by changes in water-filled pore space (WFPS. The relationship between N2O flux and WFPS was complex and non-linear, diverging from theoretical predictions of how WFPS relates to N2O flux. Nitrification made a negligible contribution to N2O flux, irrespective of soil moisture content, indicating that nitrate reduction was the dominant source of N2O. Analysis of the pooled data indicated that N2O flux was greatest at 90 and 50 % WFPS, and lowest at 70 and 30 % WFPS. This trend in N2O flux suggests a complex relationship between WFPS and nitrate-reducing processes (i.e. denitrification, dissimilatory nitrate reduction to ammonium. Changes in labile organic matter inputs, through the manipulation of leaf litter-fall, did not alter N2O flux. Comprehensive analysis of field and laboratory data demonstrated that variations in NO3− availability strongly constrained N2O flux. Habitat – a proxy for NO3− availability under field conditions – was the best predictor for N2O flux, with N-rich habitats (premontane forest, lower montane forest showing significantly higher N2O flux than N-poor habitats (upper montane forest, montane grassland. Yet, N2O flux did not respond to short-term changes in NO3− concentration.

  15. The role of diaspore banks for the restoration of floodplain meadows. Results of a long term monitoring on the Northern Upper Rhine (Germany

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    Schneider-Binder Erika

    2017-06-01

    Full Text Available The reconnection of the inner area of the island Kühkopf/Northern Upper Rhine to the hydrological dynamic of the river was the beginning of a large scale restoration programme for turning back to the previous vegetation – floodplain meadows. From the various aspects of the restoration are presented the succession phases; species with their different type of dispersal are analysed as well. A special attention is given to the role of diaspores of the soil, which play an important role in the redevelopment of floodplain meadows. Species of the diaspore bank can recur after many years, if favourable conditions are available. These are related to floods, dryness and rooting up by wild boar with the development of micro-succession stages.

  16. Variability of Soil Types in Wetland Meadows in the South of the Chilean Patagonia Variabilidad de Tipos de Suelos en Las Vegas del Sur de la Patagonia Chilena

    OpenAIRE

    Ladislava Filipová; Radim Hédl; Nilo Covacevich C.

    2010-01-01

    The wetland meadows and pastures (vegas) of the agricultural zone of the Magallanes Region and the Chilean Patagonia are productive and intensively exploited ecosystems. However, there is scarce data about the typology and the physical and chemical properties of the soils that determine the agricultural potential of vegas sites. Sampling of the main horizons of 47 soil profiles was conducted throughout the area. The profiles were described in the field and consequently classified according to...

  17. Habitat selection of the pink shrimp Farfantepenaeus paulensis and the blue crab Callinectes sapidus in an estuary in southern Brazil: influence of salinity and submerged seagrass meadows

    OpenAIRE

    Ruas, Vinicius Mendes; Rodrigues, Marcos Alaniz; Dumont, Luiz Felipe Cestari; D'Incao, Fernando

    2014-01-01

    This study was conducted in two estuarine inlets (Saco da Mangueira and Saco do Arraial) at the Patos Lagoon estuary, southern Brazil. The changes in relative abundance and size of post-larvae and juvenile shrimp Farfantepenaeus paulensis and juvenile blue crab Callinectes sapidus were compared, considering the influence of salinity and the presence of submerged seagrass meadows. The analyses were performed using generalized linear models (GLM) for abundance variations and A...

  18. Positive long-term effect of mulching on species and functional trait diversity in a nutrient-poor mountain meadow in Central Europe

    Czech Academy of Sciences Publication Activity Database

    Doležal, Jiří; Mašková, Z.; Lepš, J.; Steinbachová, D.; de Bello, Francesco; Klimešová, Jitka; Tackenberg, O.; Zemek, František; Květ, Jan

    2011-01-01

    Roč. 145, č. 1 (2011), s. 10-28 ISSN 0167-8809 R&D Projects: GA ČR GA206/99/1410; GA ČR GA526/09/0963 Institutional research plan: CEZ:AV0Z60870520; CEZ:AV0Z60050516 Keywords : community weighted means * ecosystem function * functional diversity * meadow management * niche space * redundancy analysis * traits Subject RIV: EH - Ecology, Behaviour Impact factor: 3.004, year: 2011

  19. Long term dynamics of charophytes meadows and cut-sedge beds in the wetland of Las Tablas de Daimiel (Ciudad Real, Spain: relationship with environmental disturbances

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    S. Cirujano

    2017-05-01

    Full Text Available This work analyses surface variations on charophyte meadows and cut-sedge beds in Las Tablas de Daimiel National Park (Ciudad Real, Spain from the 1950s to the present, and its relationship with the changes that have occurred in the wetland meanwhile (e.g. droughts, fires, pollution episodes. Therefore, the role of these two parameters as environmental indicators at this continental wetland has been assessed.

  20. The climate warming effect of a fen peat meadow with fluctuating water table is reduced by young alder trees

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    V. Huth

    2018-03-01

    Full Text Available Black alder (Alnus glutinosa (L. Gaertn. occurs naturally in temperate marshes and in minerotrophic peatlands and is also suitable for paludiculture - the cultivation of biomass on wet or rewetted peatland. We investigated the effect of a newly established black alder plantation on the greenhouse gas (GHG balance of a degraded fen in north-eastern Germany over a two-year period (August 2010–August 2012. We compared the alder plantation (Awet with an extensively used meadow (Mwet and a drier reference meadow (Mmoist. GHG fluxes were measured monthly to bi-monthly using the closed chamber method. Our results show that Awet was a slight net GHG (in CO2-eq sink of 3.4 ± 1.7 t ha-1 yr-1, Mwet was a moderate net GHG source of 9.6 ± 1.2 t ha 1 yr-1, and Mmoist was a strong net GHG source of 24.5 ± 1.6 t ha-1 yr-1. This was mainly driven by CO2 uptake at the two very moist (wet sites and by high CO2 release at the drier reference site. Awet was a larger CO2 sink than Mwet, probably due to additional CO2 uptake by the alder stand at Awet and carbon export in plant material harvested from Mwet. All sites were significant CH4 sources. Substantial CH4 emission peaks were observed at all sites following extraordinarily heavy precipitation during the summer of 2011, which accounted for up to 70 % of the accumulated two-year CH4 emissions. However, the Awet site generally emitted less CH4, possibly due to the effective oxygen transport mechanism in black alders. N2O emissions were negligible at all three sites. Our results indicate that the GHG balances of formerly drained fens benefit in the short term from planting of black alders, mostly due to reduced CH4 emissions. This study highlights the importance of acknowledging extreme precipitation events and groundwater fluctuations for the derivation of reliable GHG emission factors.