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Sample records for montane meadow complex

  1. 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.

  2. Montane meadows and hydrologic connections between forests and streams in the Sierra Nevada, California

    Science.gov (United States)

    Lucas, R. G.; Conklin, M. H.

    2013-12-01

    Montane meadows of the Sierra Nevada often serve as the interface between up-gradient forested area and down-gradient streamflow. We investigated the roles that meadow groundwater and evapotranspiration play in the greater catchment water cycle using a water-column data from monitoring wells and piezometers in two meadows for water years 2008-2012. Analyses include mass balance and modeling using 1-D HYDRUS. Though spatially heterogeneous, groundwater fluxes contribute to evapotranspiration (ETg) across the meadows, and are constrained by surface-water discharge. Near the meadow center groundwater discharges occur for the duration of the snow-free season, ET¬g is relatively low. At the meadow edge the groundwater flux changes from discharge to recharge when the growing season begins; also ETg increases, and major-ion concentrations in groundwater are more dilute than those near the meadow center. When groundwater is discharged throughout the meadow during snowmelt, the stream-water ion content more closely resembles water sampled from wells at the meadow edge. These trends change as the summer season progresses--groundwater is no longer discharged at the meadow edge and the stream water ion concentration matches the groundwater sampled from the center of the meadow. Slug tests performed in the monitoring wells indicate a saturated hydraulic conductivity (Kh) of meadow substrates between 10-5 and 10-6 m s-1. The upper end of this range reflects substrate with large sand fractions, while lower values reflect finer-grained or higher-organic-content substrate. Applying the higher Kh values to groundwater gradients during snowmelt results in groundwater discharge rates greater than streamflow measured at the meadow outlet. This suggests that the peat layer at the meadow surface, with significantly lower Kh values, retards groundwater discharge from the meadow during snowmelt. ETg signals in wells at the meadow edge and in wells installed just outside of the meadow

  3. Detecting Montane Meadows in the Tahoe National Forest Using LiDAR and ASTER Imagery

    Science.gov (United States)

    Lorenz, A.; Blesius, L.; Davis, J. D.

    2016-12-01

    In the Sierra Nevada mountains, meadows provide numerous hydraulic and ecosystem functions such as flood attenuation, groundwater storage, and wildlife habitat. However, many meadows have been degraded from historical land use such as water diversion, grazing, and logging. Land managers have altered management strategies for restoration purposes, but there is a lack of comprehensive data on meadow locations. Previous attempts to inventory Sierra Nevada meadows have included several remote sensing techniques including heads up digitizing and pixel based image analysis, but this has been challenging due to geographic variability, seasonal changes, and meadow health. I present a remote sensing method using multiple return LiDAR (Light Detection and Ranging) and ASTER imagery to detect montane meadows in a subset of the Tahoe National Forest. The project used LiDAR data to create a digital terrain model and digital surface model. From these models, I derived canopy height, surface slope, and watercourse for the entire study area. Literature queries returned known values for canopy height and surface slope characteristic of montane meadows. These values were used to select for possible meadows within the study area. To filter out noise, only contiguous areas greater than one acre that satisfied the queries were used. Finally, 15-meter ASTER imagery was used to de-select for areas such as dirt patches or gravel bars that might have satisfied the previous queries and meadow criteria. When using high resolution aerial imagery to assess model accuracy, preliminary results show user accuracy of greater than 80%. Further validation is still needed to improve the accuracy of modeled meadow delineation. This method allows for meadows to be inventoried without discriminating based on geographic variability, seasonal changes, or meadow health.

  4. Characterizing the Source Water for Montane Meadows to Assess Resiliency under Changing Hydroclimatic Condition

    Science.gov (United States)

    Yarnell, S. M.; Peek, R.; Bell, A.; Weixelman, D.; Viers, J. H.

    2015-12-01

    Ecologically and hydrologically functioning montane meadows provide a variety of ecosystem services and create biological hotspots in high-elevation landscapes. They serve as wetlands that filter water, attenuate floods, sequester carbon, sustain downstream flows, and provide high productivity habitat in typically lower productivity mountain regions. Their importance to watershed quality and health is well recognized, and restoration of meadows is a high priority for resource management agencies and non-governmental organizations. Yet many meadow restoration projects have limited outcomes or fail to achieve the desired effects due to a lack of understanding the underlying hydrological and geomorphic processes inherent to meadows that contribute to their resiliency. Few studies exist on how meadows are sustained through time despite various land use impacts or how the origin of water supplying the meadow (snowmelt-dominated versus regional groundwater-dominated) may influence meadow conditions. Furthermore, as climate conditions continue to change, questions remain regarding which meadows will be most resistant to and resilient from climate warming and thus have the highest potential for successful and sustainable restoration of meadow processes. We discuss these concepts and present two methods for assessing the regional and local contributions of source water to meadows as an indicator of resiliency. On a broad scale, comparisons of satellite imagery using metrics such as normalized difference vegetation index (NDVI) for regions with meadows may be useful to detect inter-annual and seasonal variations in meadow wetness and thus indicate meadow sites with larger groundwater sources that are more resilient over time. Locally, use of a hydrogeomorphic typing key that relates water source, geomorphic position, groundwater table elevation, and plant species composition may be useful to detect local groundwater sources that provide greater consistency of conditions and

  5. Hillslope and stream connections to water tables in montane meadows of the southern Sierra Nevada, California

    Science.gov (United States)

    Conklin, M. H.; Lucas, R. G.

    2011-12-01

    Montane meadows are often areas of groundwater discharge. In this study we characterized the groundwater - surface water interactions of two meadow systems and their connectivity to the surrounding catchment . We analyzed groundwater elevation data in 24 wells in two meadows located in the southern Sierra Nevada. Well transects extended from the meadow centers near the stream, to the meadow edged, and into the adjacent forest-where wells were drilled into the weathered granite saprock layer. Water samples were collected from the monitoring wells and from streams associated with the meadow systems and analyzed for major ions and stable water isotopes. Ground water elevations in the monitoring wells were used to calculate daily evapotranspiration (ET) values. These values show that locations on the meadow slopes and near the meadow edges are losing water to the atmosphere at near potential evapotranspiration rates during the height of the growing season. ET signals from wells near the meadow streams are muted, likely due to the vegetation utilizing the available surface water at these locations. Wells installed in the saprock layer, outside of the meadow boundaries, show diurnal fluctuations in sync with fluctuations observed at the meadow edge. This trend persists after the meadow vegetation senesces, indicating that groundwater elevations in the meadow, especially near the meadow edge, are significantly influenced by the adjacent hillslope saprock layer and forest ET. Geochemical sampling results indicate that the meadow streams are predominantly fed by snowmelt in the spring and early summer, moving toward more influence from base flow in the late summer and early fall. Results from the geochemical analysis established the connections of the hillslope to the meadow water tables and of the meadow subsurface waters to the down-gradient streams. Our results indicate that the these meadows are directly connected to the shallow sub-surface processes in the up gradient

  6. Modeling the gopher-meadow eco-geomorphic system on montane hillslopes

    Science.gov (United States)

    Winchell, E. W.; Doak, D. F.; Anderson, R. S.

    2013-12-01

    On montane hillslopes of Colorado's Front Range, the transport of soil by gophers can dominate the modern geomorphic system in meadows. Qualitative observations reveal that gophers prefer to forage in meadows over forests, that seedling roots are consumed by gophers, and that trees commonly occupy the rocky crests of hills overlooking open meadow hillslopes. This motivates a numerical model of gopher-mediated transport of soil and the long-term evolution of the coupled ecological-geomorphic system through quantitative observations from a manipulative experiment on meadow-centered plots in the Boulder Creek CZO in the Colorado Front Range montane forest. The ecological and geomorphic processes in the coupled system we wish to model must include: seedling establishment and damage, gopher tunneling geometries and resulting mound generation, mound material transport driven by rain and hail and by ungulate trampling, vegetative lock-down of mound material, and resulting changes in the soil depth and rockiness of the landscape. We must therefore have algorithms to capture the feedback mechanisms between gopher activity and the growth and potential death of trees, the casting of seeds and their likelihood of germination, and the spatial distribution of plants. The ecological component interacts with the soils/critical zone layer through feedbacks that include the dependence of gopher activity on root density, depth, and size, undergrowth availability, and the dependence of the rate of change of soil thickness on gradients in gopher-mediated transport. Results of a preliminary cellular automaton model which captures the essence of these geomorphic-ecological feedbacks can readily address the role of gophers in limiting the encroachment of trees into meadow patches. The bioturbation of the meadows, and the downslope transport of soil within them, is much more efficient than that in the forest, which sees little to no gopher activity. These geomorphic transport hotspots will

  7. 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,...

  8. Groundwater-surface water interactions in montane meadows of the Sierra Nevada, California

    Science.gov (United States)

    Lucas, R. G.; Conklin, M. H.

    2012-12-01

    center data indicate groundwater discharge for the entirety of the summer growing season—long after the adjacent forest soils have dried out. Analysis of the geochemical data show that major ion concentrations vary little within the individual wells but vary from the edge of the meadow to the center. Stream water samples show surface flow is dominated by snow melt in the spring and is influenced more by subsurface flow as the growing season progresses. Groundwater discharges into the center of the meadows, long after the soils the adjacent Forests have dried out. This is consistent with the results from our geochemical analysis that suggests the surface water leaving the meadow systems is more influenced by subsurface flow later in the summer. Consistent groundwater discharge, with little variation in the geochemical profile of the groundwater, suggests a shallow groundwater source that is not being fully utilized by the adjacent forest landscape. These montane meadow systems provide a window for investigating groundwater surface water interactions in the catchments of the Southern Sierra Critical Zone Observatory.

  9. Determining the effects of cattle grazing treatments on Yosemite toads (Anaxyrus [=Bufo] canorus in montane meadows.

    Directory of Open Access Journals (Sweden)

    Susan K McIlroy

    Full Text Available Amphibians are experiencing a precipitous global decline, and population stability on public lands with multiple uses is a key concern for managers. In the Sierra Nevada Mountains (California, USA, managers have specifically identified livestock grazing as an activity that may negatively affect Yosemite toads due to the potential overlap of grazing with toad habitat. Grazing exclusion from Yosemite toad breeding and rearing areas and/or entire meadows have been proposed as possible management actions to alleviate the possible impact of cattle on this species. The primary objective of this study was to determine if different fencing treatments affect Yosemite toad populations. We specifically examined the effect of three fencing treatments on Yosemite toad breeding pool occupancy, tadpoles, and young of the year (YOY. Our hypothesis was that over the course of treatment implementation (2006 through 2010, Yosemite toad breeding pool occupancy and early life stage densities would increase within two fencing treatments relative to actively grazed meadows due to beneficial changes to habitat quality in the absence of grazing. Our results did not support our hypothesis, and showed no benefit to Yosemite toad presence or early life stages in fenced or partially fenced meadows compared to standard USDA Forest Service grazing levels. We found substantial Yosemite toad variation by both meadow and year. This variation was influenced by meadow wetness, with water table depth significant in both the tadpole and YOY models.

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

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    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

  11. Great Meadows National Wildlife Refuge Complex: Monthly Narrative January

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This monthly narrative report for Great Meadows National Wildlife Refuge Complex outlines Refuge accomplishments during January 1998. The report begins with a...

  12. Using sensitive montane amphibian species as indicators of hydroclimatic change in meadow ecosystems of the Sierra Nevada, California

    Science.gov (United States)

    Peek, R.; Viers, J.; Yarnell, S. M.

    2012-12-01

    Climate change can affect sensitive species and ecosystems in many ways, yet sparse data and the inability to apply various climate models at functional spatial scales often prevents relevant research from being utilized in conservation management plans. Climate change has been linked to declines and disturbances in a multitude of species and habitats, and in California, one of the greatest climatic concerns is the predicted reduction in mountain snowpack and associated snowmelt. These decreases in natural storage of water as snow in mountain regions can affect the timing and variability of critical snowmelt runoff periods—important seasonal signals that species in montane ecosystems have evolved life history strategies around—leading to greater intra-annual variability and diminished summer and fall stream flows. Although many species distribution models exist, few provide ways to integrate continually updated and revised Global Climate Models (GCMs), hydrologic data unique to a watershed, and ecological responses that can be incorporated into conservation strategies. This study documents a novel and applicable method of combining boosted regression tree (BRT) modeling and species distributions with hydroclimatic data as a potential management tool for conservation. Boosted regression trees are suitable for ecological distribution modeling because they can reduce both bias and variance, as well as handle sharp discontinuities common in sparsely sampled species or large study areas. This approach was used to quantify the effects of hydroclimatic changes on the distribution of key riparian-associated amphibian species in montane meadow habitats in the Sierra Nevada at the sub-watershed level. Based on modeling using current species range maps in conjunction with three climate scenarios (near, mid, and far), extreme range contractions were observed for all sensitive species (southern long-toed salamander, mountain yellow-legged frog, Yosemite toad) by the year

  13. Effects of experimentally reduced snowpack and passive warming on montane meadow plant phenology and floral resources

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    Sherwood, J.A.; Debinski, D.M.; Caragea, P.C.; Germino, Matthew

    2017-01-01

    Climate change can have a broad range of effects on ecosystems and organisms, and early responses may include shifts in vegetation phenology and productivity that may not coincide with the energetics and forage timing of higher trophic levels. We evaluated phenology, annual height growth, and foliar frost responses of forbs to a factorial experiment of snow removal (SR) and warming in a high-elevation meadow over two years in the Rocky Mountains, United States. Species included arrowleaf balsamroot (Balsamorhiza sagittata, early-season emergence and flowering) and buckwheat (Eriogonum umbellatum, semi-woody and late-season flowering), key forbs for pollinator and nectar-using animal communities that are widely distributed and locally abundant in western North America. Snow removal exerted stronger effects than did warming, and advanced phenology differently for each species. Specifically, SR advanced green-up by a few days for B. sagittata to >2 wk in E. umbellatum, and led to 5- to 11-d advances in flowering of B. sagittata in one year and advances in bud break in 3 of 4 species/yr combinations. Snow removal increased height of E. umbellatum appreciably (~5 cm added to ~22.8 cm in control), but led to substantial increases in frost damage to flowers of B. sagittata. Whereas warming had no effects on E. umbellatum, it increased heights of B. sagittata by >6 cm (compared to 30.7 cm in control plots) and moreover led to appreciable reductions in frost damage to flowers. These data suggest that timing of snowmelt, which is highly variable from year to year but is advancing in recent decades, has a greater impact on these critical phenological, growth, and floral survival traits and floral/nectar resources than warming per se, although warming mitigated early effects of SR on frost kill of flowers. Given the short growing season of these species, the shifts could cause uncoupling in nectar availability and timing of foraging.

  14. Gopher eskers, mounds, and stonelines: Evidence of the annual to centennial impacts of gophers in the montane meadows of Colorado's Front Range

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    Winchell, E. W.; Lombardi, E. M.; Marquez, J. A.; Doak, D. F.; Anderson, R. S.

    2014-12-01

    Within the critical zone on montane hillslopes of Colorado's Front Range, qualitative observations suggest that gophers not only dominate the modern meadow geomorphic rates, but are involved in a geomorphic-ecological feedback system that governs meadow migration on decadal-millennial time scales. Our observations suggest that gopher intensity and location is pertinent to forest/meadow (FM) dynamics. Field mapping of gopher activity as the snow melts in the spring revealed that subnivean tubes ("eskers") are tightly clustered at the FM boundary while mounds generated over the remainder of the summer are concentrated strictly in the meadows. This suggests that gophers spend the winter months at the FM interface and spend the warmer seasons within the meadows. We hypothesize that variations in snow depth drive this spatial-temporal pattern of gopher activity; deeper snow near the FM boundary provides greater insulation, as near-surface ground temperatures in the wind-scoured meadow centers are colder. This motivates our initiation of monitoring and modeling of near-surface temperature across a FM pair. Numerical modeling supports qualitative observations that the following geomorphic-ecological processes are active: seedling establishment and damage, gopher tunneling and resulting mound generation, mound material transport driven by ungulate trampling, vegetative lock-down of mound material, and resulting changes in the soil depth of the landscape. This year's observations suggest that we must add to this mix the annual cycle of the gopher activity. Finally, probing and soil pits within the meadows reveal that on longer timescales gopher activity leads to the development of a well-mixed upper soil layer that is sharply bounded below by high concentrations of large stones ("stone lines") within the glacial till substrate of the hillslopes. The mean diameter of mound surface grains is half that of clasts comprising the stone lines. This motivates documentation of soil

  15. Great Meadows National Wildlife Refuge Complex: Annual narrative report: Calendar year 1989

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge Complex outlines Refuge accomplishments during the 1989 calendar year. The report begins with...

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

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    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...

  17. Differential meadows

    NARCIS (Netherlands)

    J.A. Bergstra; A. Ponse

    2008-01-01

    A meadow is a zero totalised field (0^{-1}=0), and a cancellation meadow is a meadow without proper zero divisors. In this paper we consider differential meadows, i.e., meadows equipped with differentiation operators. We give an equational axiomatization of these operators and thus obtain a finite b

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

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    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.

  19. Quantifying seasonal volume of groundwater in high elevation meadows: Implications for complex aquifer geometry in a changing climate

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    Ciruzzi, Dominick M.

    . In order to test this hypothesis, this research first identified complex aquifer geometry controlled by bedrock depths from a ground-penetrating radar field campaign in Tuolumne Meadows, CA. This research then quantified the hydrogeologic impacts of a uniform sediment thickness model against a variable sediment thickness model under scenarios that simulated different high elevation meadows by incorporating ranges of hydraulic conductivity and topographic gradient. These scenarios also tested different stream flow and recharge rates, which simulated different volumes of snowpack. Results imply that bedrock geometry impact both the timing and magnitude of volume of groundwater (i.e. active storage) retention as well as release to streams and vegetation under both current and future snowpack simulations. In most cases, a uniform thickness meadow overestimated volume of groundwater retained from recharge and released to the stream both spatially and temporally. In doing so, volume of surface water transferred to downstream users was also overestimated. These overestimations are significant and, depending on the type of meadow, can miscalculate the water supply to San Francisco by several days worth of water. This research also indicated a reduction of up to 70% water supply from these meadows as a result of future decreases in snowpack. Spatially within the meadow, a uniform thickness model further overestimated volume of groundwater nearest to bedrock outcrops. This suggested that a uniform thickness model did not successfully identify spatially vulnerable regions on the meadow scale. This research concludes that efficient and effective monitoring and management of the water to and from these ecosystems must consider the substantial impacts of complex aquifer geometry.

  20. Complex interactions between a legume and two grasses in a subalpine meadow.

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    Marty, Charles; Pornon, André; Escaravage, Nathalie; Winterton, Peter; Lamaze, Thierry

    2009-10-01

    Interactions between plants are a complex combination of positive and negative interactions, with the net outcome depending on environmental contexts. The more frequent association of Trifolium alpinum (legume) with Festuca eskia than with Nardus stricta (grasses) in many Pyrenean subalpine meadows suggests a differential ability to use nitrogen (N) derived from N(2) fixation. In the field, we investigated the interactions between the legume and grasses and, in the glasshouse, the transfer of (15)N from the legume to the grasses. In one grass-Trifolium mixture, the legume had a strong positive effect on the biomass and N content of the grass as compared to pure grass stands. When both grasses grew together with the legume, only Festuca benefited from the presence of Trifolium but, surprisingly, the benefit decreased with increasing Trifolium abundance. Leaf labeling experiments with (15)N-NH(4)(+) revealed a higher transfer of (15)N from Trifolium to Festuca than to Nardus, suggesting a more direct N pathway between the two species. This more direct pathway could prevent Nardus from benefiting from the legume N in the three-species mixtures. Thus, the positive interactions between N-fixers and nonfixers appear to be largely species-specific and to depend strongly on the species in the plant assemblage.

  1. Complex responses of spring vegetation growth to climate in a moisture-limited alpine meadow.

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    Ganjurjav, Hasbagan; Gao, Qingzhu; Schwartz, Mark W; Zhu, Wenquan; Liang, Yan; Li, Yue; Wan, Yunfan; Cao, Xujuan; Williamson, Matthew A; Jiangcun, Wangzha; Guo, Hongbao; Lin, Erda

    2016-03-17

    Since 2000, the phenology has advanced in some years and at some locations on the Qinghai-Tibetan Plateau, whereas it has been delayed in others. To understand the variations in spring vegetation growth in response to climate, we conducted both regional and experimental studies on the central Qinghai-Tibetan Plateau. We used the normalized difference vegetation index to identify correlations between climate and phenological greening, and found that greening correlated negatively with winter-spring time precipitation, but not with temperature. We used open top chambers to induce warming in an alpine meadow ecosystem from 2012 to 2014. Our results showed that in the early growing season, plant growth (represented by the net ecosystem CO2 exchange, NEE) was lower in the warmed plots than in the control plots. Late-season plant growth increased with warming relative to that under control conditions. These data suggest that the response of plant growth to warming is complex and non-intuitive in this system. Our results are consistent with the hypothesis that moisture limitation increases in early spring as temperature increases. The effects of moisture limitation on plant growth with increasing temperatures will have important ramifications for grazers in this system.

  2. Groundwater flow and storage within an alpine meadow-talus complex

    Directory of Open Access Journals (Sweden)

    A. F. McClymont

    2010-06-01

    Full Text Available The different types of geological deposits and rock formations found in alpine watersheds play key roles in regulating the rate and timing of runoff to mountain rivers. Talus and alpine meadows are dominant features in these areas, but scant data exist for their capacity to store and transmit groundwater. To gain further understanding of these processes, we have undertaken a combined geophysical and hydrological study of a small (2100 m2 alpine meadow and surrounding talus within the Lake O'Hara watershed in the Canadian Rockies. Several intersecting ground-penetrating radar (GPR and electrical resistivity tomography (ERT profiles and a seismic refraction profile were acquired to map the thickness of the talus and to image the topography of the bedrock basin that underlies the meadow. From analysis of the GPR and seismic profiles, we estimate that the talus deposits are relatively thin (<6 m. Combined interpretations from the GPR and ERT data show that the fine-grained sediment comprising the meadow basin has a total volume of ca. 3300 m3 and has a maximum thickness of ca. 4 m. Annual snow surveys and stream gauging reveal that the total input volume of snowmelt and rainfall to the meadow basin is several times larger than its groundwater storage capacity, giving rise to low total-dissolved species concentrations (14–21 mg/L within the meadow groundwater. Observations from four piezometers established on the meadow show that the water table fluctuates rapidly in response to spring snowmelt and precipitation events but otherwise maintains a relatively stable depth of 0.3–0.4 m below the meadow surface during summer months. A slug test performed on one of the piezometers indicated that the saturated hydraulic conductivity of the shallow meadow sediments is 2.5×10−7 m/s. We suggest that a bedrock saddle imaged underneath the southern end of the meadow forms a natural constriction to subsurface flow out of the

  3. Groundwater flow and storage within an alpine meadow-talus complex

    Directory of Open Access Journals (Sweden)

    A. F. McClymont

    2010-02-01

    Full Text Available The different types of geological deposits and rock formations found in alpine watersheds play key roles in regulating the rate and timing of runoff to mountain rivers. Talus and alpine meadows are dominant features in these areas, but scant data exist for their capacity to store and transmit groundwater. To gain further understanding of these processes, we have undertaken a combined geophysical and hydrological study of a small (2100 m2 alpine meadow and surrounding talus within the Lake O'Hara watershed in the Canadian Rockies. Several intersecting ground-penetrating radar (GPR and electrical resistivity tomography (ERT profiles and a seismic refraction profile were acquired to map the thickness of the talus and to image the topography of the bedrock basin that lies under the meadow. From analysis of the GPR and seismic profiles, we estimate that the talus deposits are relatively thin (<6 m. Combined interpretations from the GPR and ERT data show that the fine-grained sediment, that the meadow basin is comprised of, has a total volume of ca. 3300 m3 and has a maximum thickness of ca. 4 m. Annual snow surveys and stream gauging reveal that the total input volume of snowmelt and rainfall to the meadow basin is several times larger than its groundwater storage capacity, giving rise to low total-dissolved species concentrations (14–21 mg/L within the meadow groundwater. Observations from four piezometers established on the meadow show that the water table fluctuates rapidly in response to spring snowmelt and precipitation events but otherwise maintains a relatively stable depth of 0.3–0.4 m below the meadow surface during summer months. A slug test performed on one of the piezometers indicated that the saturated hydraulic conductivity of the shallow meadow sediments is 2.5×10−7 m/s. We suggest that a bedrock saddle imaged underneath the southern end of the meadow forms a natural constriction to subsurface

  4. Effects of habitat management treatments on plant community composition and biomass in a Montane wetland

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    Austin, J.E.; Keough, J.R.; Pyle, W.H.

    2007-01-01

    Grazing and burning are commonly applied practices that can impact the diversity and biomass of wetland plant communities. We evaluated the vegetative response of wetlands and adjacent upland grasslands to four treatment regimes (continuous idle, fall prescribed burning followed by idle, annual fall cattle grazing, and rotation of summer grazing and idle) commonly used by the U.S. Fish and Wildlife Service. Our study area was Grays Lake, a large, montane wetland in southeastern Idaho that is bordered by extensive wet meadows. We identified seven plant cover types, representing the transition from dry meadow to deep wetland habitats: mixed deep marsh, spikerush slough, Baltic rush (Juncus balticus), moist meadow, alkali, mesic meadow, and dry meadow. We compared changes in community composition and total aboveground biomass of each plant cover type between 1998, when all units had been idled for three years, and 1999 (1 yr post-treatment) and 2000 (2 yr post-treatment). Analysis using non-metric multidimensional scaling indicated that compositional changes varied among cover types, treatments, and years following treatment. Treatment-related changes in community composition were greatest in mixed deep marsh, Baltic rush, and mesic meadow. In mixed deep marsh and Baltic rush, grazing and associated trampling contributed to changes in the plant community toward more open water and aquatic species and lower dominance of Baltic rush; grazing and trampling also seemed to contribute to increased cover in mesic meadow. Changing hydrological conditions, from multiple years of high water to increasing drought, was an important factor influencing community composition and may have interacted with management treatments. Biomass differed among treatments and between years within cover types. In the wettest cover types, fall burning and grazing rotation treatments had greater negative impact on biomass than the idle treatment, but in drier cover types, summer grazing stimulated

  5. [Ash Meadows Purchase Proposal

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A proposal sent to the Richard King Mellon Foundation for a loan to fund the purchase of Ash Meadows by the Nature Conservancy. Ash Meadows, set outside of Las Vegas...

  6. Continuous 1985–2012 Landsat Monitoring to Assess Fire Effects on Meadows in Yosemite National Park, California

    Directory of Open Access Journals (Sweden)

    Christopher E. Soulard

    2016-04-01

    Full Text Available 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.

  7. 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.

  8. Environmental complexity and biodiversity: the multi-layered evolutionary history of a log-dwelling velvet worm in Montane Temperate Australia.

    Science.gov (United States)

    Bull, James K; Sands, Chester J; Garrick, Ryan C; Gardner, Michael G; Tait, Noel N; Briscoe, David A; Rowell, David M; Sunnucks, Paul

    2013-01-01

    Phylogeographic studies provide a framework for understanding the importance of intrinsic versus extrinsic factors in shaping patterns of biodiversity through identifying past and present microevolutionary processes that contributed to lineage divergence. Here we investigate population structure and diversity of the Onychophoran (velvet worm) Euperipatoides rowelli in southeastern Australian montane forests that were not subject to Pleistocene glaciations, and thus likely retained more forest cover than systems under glaciation. Over a ~100 km transect of structurally-connected forest, we found marked nuclear and mitochondrial (mt) DNA genetic structuring, with spatially-localised groups. Patterns from mtDNA and nuclear data broadly corresponded with previously defined geographic regions, consistent with repeated isolation in refuges during Pleistocene climatic cycling. Nevertheless, some E. rowelli genetic contact zones were displaced relative to hypothesized influential landscape structures, implying more recent processes overlying impacts of past environmental history. Major impacts at different timescales were seen in the phylogenetic relationships among mtDNA sequences, which matched geographic relationships and nuclear data only at recent timescales, indicating historical gene flow and/or incomplete lineage sorting. Five major E. rowelli phylogeographic groups were identified, showing substantial but incomplete reproductive isolation despite continuous habitat. Regional distinctiveness, in the face of lineages abutting within forest habitat, could indicate pre- and/or postzygotic gene flow limitation. A potentially functional phenotypic character, colour pattern variation, reflected the geographic patterns in the molecular data. Spatial-genetic patterns broadly match those in previously-studied, co-occurring low-mobility organisms, despite a variety of life histories. We suggest that for E. rowelli, the complex topography and history of the region has led to

  9. Environmental complexity and biodiversity: the multi-layered evolutionary history of a log-dwelling velvet worm in Montane Temperate Australia.

    Directory of Open Access Journals (Sweden)

    James K Bull

    Full Text Available Phylogeographic studies provide a framework for understanding the importance of intrinsic versus extrinsic factors in shaping patterns of biodiversity through identifying past and present microevolutionary processes that contributed to lineage divergence. Here we investigate population structure and diversity of the Onychophoran (velvet worm Euperipatoides rowelli in southeastern Australian montane forests that were not subject to Pleistocene glaciations, and thus likely retained more forest cover than systems under glaciation. Over a ~100 km transect of structurally-connected forest, we found marked nuclear and mitochondrial (mt DNA genetic structuring, with spatially-localised groups. Patterns from mtDNA and nuclear data broadly corresponded with previously defined geographic regions, consistent with repeated isolation in refuges during Pleistocene climatic cycling. Nevertheless, some E. rowelli genetic contact zones were displaced relative to hypothesized influential landscape structures, implying more recent processes overlying impacts of past environmental history. Major impacts at different timescales were seen in the phylogenetic relationships among mtDNA sequences, which matched geographic relationships and nuclear data only at recent timescales, indicating historical gene flow and/or incomplete lineage sorting. Five major E. rowelli phylogeographic groups were identified, showing substantial but incomplete reproductive isolation despite continuous habitat. Regional distinctiveness, in the face of lineages abutting within forest habitat, could indicate pre- and/or postzygotic gene flow limitation. A potentially functional phenotypic character, colour pattern variation, reflected the geographic patterns in the molecular data. Spatial-genetic patterns broadly match those in previously-studied, co-occurring low-mobility organisms, despite a variety of life histories. We suggest that for E. rowelli, the complex topography and history of the

  10. Montane wetland water chemistry, Uinta Mountains, Utah

    Science.gov (United States)

    Severson, K. S.; Matyjasik, M.; Ford, R. L.; Hernandez, M. W.; Welsh, S. B.; Summers, S.; Bartholomew, L. M.

    2009-12-01

    This study attempts to determine the relationship between surface and groundwater chemistry and wetland characteristics within the Reader Lakes watershed, Uinta Mountains. The dominant rock type in the study area is quartz sandstone of the Hades Pass formation, Unita Mountain Group (Middle Proterozoic). Minor amounts of interbedded arkose and illite-bearing shale are also present. Water chemistry data have been collected from more than one hundred locations during the 2008 and 2009 summer seasons. The Reader Creek watershed is approximately 9.8 km long and about 3.5 km wide in the central portion of the basin. Direct precipitation is the primary source of groundwater recharge and the area is typically covered by snow from November until May. Four distinct wetland complexes, designated as the upper, middle, lower and the sloping fen, constitute the major wetland environments in the study area. The chemistry of the melt water from the high-elevation snowfield is affected by weathering of incorporated atmospheric dust and surface rocks. Total dissolved solids in both years were between 7 and 9 mg/L. Major anions include HCO3 (averaging 4.0 mg/L), SO4 (1.3 mg/L), NO3 (0.9 mg/L), Cl (0.8 mg/L), F (0.07 mg/L), PO4 (0.03 mg/L), and Br(0.015 mg/L). Major cations include Na (1.1 mg/L), Ca (1.0 mg/L), K (0.28 mg/L), and Mg (0.15 mg/L). Groundwater concentrations in the lower meadow, as measured in piezomters, are distinctly different, with the following maximum concentrations of anions: HCO3 (36.7 mg/L), SO4 (5.0 mg/L), Cl (3.4 mg/L), NO3 (0.9 mg/L), PO4 (0.28 mg/L), F (0.23 mg/L), Br (0.12 mg/L), and cations: Ca (22 mg/L), Na (4.6 mg/L), Mg (3.4 mg/L), and K (1.8 mg/L)- with a maximum value of 83 mg/L for total dissolved solids. Waters in Reader Creek, the main trunk channel, are typically sodium-potassium and sodium -potassium bicarbonate, with some calcium-bicarbonate, mostly in the middle part of the watershed. Groundwater from springs is sodium-potassium in the upper

  11. 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.

  12. Great Meadows National Wildlife Refuge Cpmplex: Monthly Narrative February

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This monthly narrative report for Great Meadows National Wildlife Refuge Complex outlines Refuge accomplishments during February 1998. The report begins with a...

  13. 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

  14. 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.

  15. 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...... drastically. It overwinters as larvae in a puparium, in the soil, and begins to hatch on average in late April, but the time is de-pending on the temperature. Emergence of the meadow-grass gall midge in spring takes place over a 2-3 week period. Beginning of emergence of the meadow-grass gall midge takes...... maximum. Therefore, the spraying frequency could be lowered signifi-cantly and in many cases lowered to only one insecticide application in meadow-grass every year....

  16. Mountain Meadows Dacite: Oligocene intrusive complex that welds together the Los Angeles Basin, northwestern Peninsular Ranges, and central Transverse Ranges, California

    Science.gov (United States)

    McCulloh, Thane H.; Beyer, Larry A.; Morin, Ronald W.

    2001-01-01

    Dikes and irregular intrusive bodies of distinctive Oligocene biotite dacite and serially related hornblende latite and felsite occur widely in the central and eastern San Gabriel Mountains, southern California, and are related to the Telegraph Peak granodiorite pluton. Identical dacite is locally present beneath Middle Miocene Topanga Group Glendora Volcanics at the northeastern edge of the Los Angeles Basin, where it is termed Mountain Meadows Dacite. This study mapped the western and southwestern limits of the dacite distribution to understand the provenance of derived redeposited clasts, to perceive Neogene offsets on several large strike-slip faults, to test published palinspastic reconstructions, and to better understand the tectonic boundaries that separate contrasting pre-Tertiary rock terranes where the Peninsular Ranges meet the central and western Transverse Ranges and the Los Angeles Basin. Transported and redeposited clasts of dacite-latite occur in deformed lower Miocene and lower middle Miocene sandy conglomerates (nonmarine, nearshore, and infrequent upper bathyal) close to the northern and northeastern margins of the Los Angeles Basin for a distance of nearly 60 km. Tie-lines between distinctive source suites and clast occurrences indicate that large tracts of the ancestral San Gabriel Mountains were elevated along range-bounding faults as early as 16–15 Ma. The tie-lines prohibit very large strike-slip offsets on those faults. Transport of eroded dacite began south of the range as early as 18 Ma. Published and unpublished data about rocks adjacent to the active Santa Monica-Hollywood-Raymond oblique reverse left-lateral fault indicate that cumulative left slip totals 13–14 km and total offset postdates 7 Ma. This cumulative slip, with assembly of stratigraphic and paleogeographic data, invalidates prior estimates of 60 to 90 km of left slip on these faults beginning about 17–16 Ma. A new and different palinspastic reconstruction of a region

  17. AshMeadowsNaucorid_CH

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify the areas where final critical habitat for the Ash Meadows Naucorid (Ambrysus amargosus) occur. "Nevada, Nye County. Point of Rocks Springs and...

  18. AshMeadowsNaucorid_CH

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify the areas where final critical habitat for the Ash Meadows Naucorid (Ambrysus amargosus) occur. "Nevada, Nye County. Point of Rocks Springs and...

  19. Effects of environment and grazing disturbance on tree establishment in meadows of the central Cascade Range, Oregon, USA

    Energy Technology Data Exchange (ETDEWEB)

    Miller, E.A.; Halpern, C.B. [Washington Univ., Seattle, WA (United States). Coll. of Forest Resources

    1998-04-01

    Within the last century there has been widespread establishment of trees in mountain meadows of the Pacific Northwest. We reconstructed patterns of tree invasion at 17 meadow sites in the central Cascade Range of Oregon, USA - sites representing diverse physical environments and vegetation types and experiencing different histories of recent anthropogenic disturbance (sheep grazing). Spatial distributions and age structures of invasive tree populations were analysed with respect to climatic records and grazing history. Patterns of establishment varied considerably among meadows, reflecting strong differences in environment and grazing history. In montane hydric meadows, tree establishment was spatially clumped beneath large old trees and on elevated microsites; however the timing of invasion differed between sites with stable versus fluctuating water tables. In upland mesic/dry montane meadows, timing of invasion corresponded with cessation of sheep grazing (early 1940s) and the onset of wetter summers (mid 1940s). In the subalpine zone, climate and aspect interacted to produce contrasting histories of invasion on north- and south-faced slopes. Establishment on north-facing slopes, concentrated in heath-shrub communities, coincided with regional warming (1920-1945) when snowpacks were lighter and melted earlier. Recruitment of trees onto south-facing slopes occurred later, when conditions were wetter (1945-1985). In many environments, the spatial distribution of recruitment suggests that once trees have established, autogenic factors become increasingly important as individual trees or groups of trees alter the physical or biotic conditions that once inhibited establishment. Knowledge of the factors that influence invasion, and of their varying importance across gradients in environment and vegetation, is critical to predicting future changes in these dynamic systems 74 refs, 12 figs, 2 figs

  20. Meadow Fescue: The Forgotten Grass

    Science.gov (United States)

    In 1990, we found an unknown grass growing on a farm in southwestern Wisconsin. We have identified this grass as meadow fescue, popular in the late 19th century and early 20th century before tall fescue was imported into the USA. The grass was established throughout the Charles Opitz farm by harve...

  1. Registration of Arsenal meadow bromegrass

    Science.gov (United States)

    The United States Department of Agriculture (ARS) announces the release of the cultivar 'Arsenal' meadow bromegrass [Bromus biebersteinii Roem. & Schult. (excluded)] for use on semiarid rangelands and non-irrigated pastures as a rapid establishing forage grass with early spring growth, good fall nut...

  2. Ninigret National Wildlife Refuge Complex: Ninigret National Wildlife Refuge, Block Island National Wildlife Refuge, Sachuest Point National Wildlife Refuge, Trustom Pond National Wildlife Refuge, Salt Meadow National Wildlife Refuge: Annual narrative report: Calendar year 1984

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ninigret NWR, Salt Meadow NWR, Trustom Pond NWR, Sachuest Point NWR, and Block Island NWR outlines Refuge accomplishments during the...

  3. Ninigret National Wildlife Refuge Complex: Ninigret National Wildlife Refuge, Block Island National Wildlife Refuge, Sachuest Point National Wildlife Refuge, Trustom Pond National Wildlife Refuge, Salt Meadow National Wildlife Refuge: Annual narrative report: Calendar year 1984

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ninigret NWR, Salt Meadow NWR, Trustom Pond NWR, Sachuest Point NWR, and Block Island NWR outlines Refuge accomplishments during the...

  4. Desert National Wildlife Refuge Complex: Ash Meadows, Desert, Moapa Valley, and Pahranagat National Wildlife Refuges: Final Comprehensive Conservation Plan and Environmental Impact Statement

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Comprehensive Conservation Plan (CCP) was written to guide management on Desert NWR Complex for the next 15 years. This plan outlines the Complex vision and...

  5. HYDROLOGY OF CENTRAL GREAT BASIN MEADOW ECOSYSTEMS – EFFECTS OF STREAM INCISION

    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. Our interdisciplinary group has investigated 1) the interrelationships of geomorphology, hydrology, and vegetation; and 2) ...

  6. Plant species dominance shifts across erosion edge-meadow transects in the Swiss Alps.

    Science.gov (United States)

    Huck, Corinne; Körner, Christian; Hiltbrunner, Erika

    2013-03-01

    While exerting no obvious function under "average" environmental conditions, the presence of certain plant specialists becomes crucial in the event of a complete failure of a community due to severe disturbance such as landslides. Plants capable of growing at erosion edges may act as potential edge-engineers by coping with unstable ground and stabilizing the soil with their roots. We hypothesized that life conditions at erosion edges select for a particular set of specialists or species with specific traits, the identification of which was the aim of the study. Across 17 small-scale transects (0.40 × 1.60 m) from intact meadows to landslide edges (Ursern Valley, Swiss Alps, c. 1,600 m a.s.l.), we quantified plant species abundance by the point intercept method and characterized growth conditions based on Landolt's indicator values, leaf δ(13)C, and volumetric soil moisture in the uppermost soil layers. We observed a clear change of plant species composition and relative abundance from the meadow to the edge, presumably induced by the 25 % lower soil moisture and microclimatic exposure. Species richness at the edge was two-thirds of that in the meadow, but was positively correlated with species richness of the adjacent meadow. Species with "edge-preference" had either (1) rolled or festucoid leaves like Festuca spp., Avenella flexuosa and Nardus stricta, or (2) small, scleromorphic leaves like Vaccinium vitis-idaea, Calluna vulgaris and Thymus ssp. Graminoids with rolled/festucoid leaves were found to be the most dominant edge-specialists. The grass Festuca valesiaca s.l. emerged as the most dominant plant species at the edge, having an 11-times higher cover at the edge than in the meadow. In this montane grassland, a single species contributes to the stabilization of erosion edges and may be regarded as a potential keystone species for slope stability and regeneration after landslides even its role has not so far been established.

  7. Tree diversity in sub-montane and lower montane primary rain forests in Central Sulawesi

    NARCIS (Netherlands)

    Culmsee, H.; Pitopang, R.

    2009-01-01

    The tree diversity of sub-montane and lower montane primary forests is studied in plot-based inventories on two sites in Lore Lindu National Park, Central Sulawesi. Out of 166 species in total, 50 % are new records for Sulawesi (19 %) or the Central Sulawesi province (31 %). Species richness

  8. SEMI-NATURAL MEADOWS AND O THER TRADITIONAL RURAL BIOTOPES

    Directory of Open Access Journals (Sweden)

    H. JUTILA

    1999-01-01

    Full Text Available In the middle of 19th century the area of meadows was at its largest in Finland, about 1.6 million hectares. Thereafter the meadow area has decreased dramatically. Finnish Environment Institute has led the inventory of traditional rural or agricultural biotopes in Finland since 1992. Until now the results have been published only in the regions of Satakunta, North Ostrobothnia and North Karelia. In Satakunta 280 sites of valuable traditional rural biotopes (1160 hectares were found and most of them were grazed by cattle. Of these 39% (457 ha were meadows including shore meadows. All meadows with the exception of shore meadows were very small (< 2 ha. Other traditional rural biotopes were wooded pastures (258 ha, grazed forests (183 ha and some others (79 ha. The meadows were classified according to the physiognomic and floristic determinants. Nutrient-poor rocky meadows, nutrient-poor dry short herb meadows, dry grass meadows, dry grassherb meadows, scrub meadows and humid or moist meadows were rare in Satakunta. Mesophilous meadows were divided to short herb meadows, grass meadows and tall herb meadows and they covered altogether 96 ha (8% in Satakunta. Grazed lake and river shore meadows covered about 110 ha (9,5% and were quite often dominated by short sedges and grasses. Studied seashore meadows covered 188 ha, making 16 % of all valuable traditional rural biotopes in Satakunta. There were three very large seashore meadows in the Pori region. In the traditional rural biotopes of Satakunta 14 nationally threatened species were found.

  9. SEMI-NATURAL MEADOWS AND O THER TRADITIONAL RURAL BIOTOPES

    Directory of Open Access Journals (Sweden)

    H. JUTILA

    1999-04-01

    Full Text Available In the middle of 19th century the area of meadows was at its largest in Finland, about 1.6 million hectares. Thereafter the meadow area has decreased dramatically. Finnish Environment Institute has led the inventory of traditional rural or agricultural biotopes in Finland since 1992. Until now the results have been published only in the regions of Satakunta, North Ostrobothnia and North Karelia. In Satakunta 280 sites of valuable traditional rural biotopes (1160 hectares were found and most of them were grazed by cattle. Of these 39% (457 ha were meadows including shore meadows. All meadows with the exception of shore meadows were very small (< 2 ha. Other traditional rural biotopes were wooded pastures (258 ha, grazed forests (183 ha and some others (79 ha. The meadows were classified according to the physiognomic and floristic determinants. Nutrient-poor rocky meadows, nutrient-poor dry short herb meadows, dry grass meadows, dry grassherb meadows, scrub meadows and humid or moist meadows were rare in Satakunta. Mesophilous meadows were divided to short herb meadows, grass meadows and tall herb meadows and they covered altogether 96 ha (8% in Satakunta. Grazed lake and river shore meadows covered about 110 ha (9,5% and were quite often dominated by short sedges and grasses. Studied seashore meadows covered 188 ha, making 16 % of all valuable traditional rural biotopes in Satakunta. There were three very large seashore meadows in the Pori region. In the traditional rural biotopes of Satakunta 14 nationally threatened species were found.

  10. A new species of Gulella (Pulmonata: Streptaxidae) from montane forest in the Ndoto Mountains, Kenya

    NARCIS (Netherlands)

    Rowson, B.; Seddon, M.B.; Tattersfield, P.

    2009-01-01

    Gulella mkuu spec. nov. is described from montane forest in the isolated Ndoto Mountains of northern Kenya. Although exceptionally large for the genus, shell, genitalia and radula features suggest it is more closely related to the "G. sellae-ugandensis" complex than to other very large East African

  11. Montane conifer fuel dynamics, Yosemite National Park

    Science.gov (United States)

    van Wagtendonk, J.W.; Moore, P.E.

    1997-01-01

    Litter and woody fuel accumulation rates over 7 years for 7 montane Sierra Nevada conifer species, including giant sequoia, ponderosa pine, sugar pine, Jeffrey pine, incense-cedar and white fir. Data are from four sites per size class per species with four size classes each. Nonspatial, georeferenced.

  12. Remote influence of off-shore fish farm waste on Mediterranean seagrass (Posidonia oceanica) meadows.

    Science.gov (United States)

    Ruiz, J M; Marco-Méndez, C; Sánchez-Lizaso, J L

    2010-04-01

    The aim of this study was estimating the remote influence of waste dispersed from a large off-shore fish farm complex (6197 ton year(-1)) on the near-shore Posidonia oceanica meadow (26-27 m deep) located at a distance of 3 km. Measurements of isotopic nitrogen content in epiphytes and seagrass leaf tissues, epiphyte biomass, shoot size, herbivory pressure, shoot density and seagrass meadow cover, performed in this meadow (FA area) were compared with those obtained in an undisturbed control meadow (CA area) to evaluate: (1) the remote influence of waste and (2) the impact of such influence on seagrass condition. In addition, delta(15)N measurements in particulate organic matter of natural and anthropogenic origin were used in a single-isotope mixing model to elucidate the relative contributions of these sources to the isotopic N signal measured in epiphytes and leaf tissues. Total tissue N content was similar between meadow areas, but delta(15)N signatures were significantly higher in the FA area than in the CA area both in epiphytes and seagrass leaf tissues. Results from the mixing model, together with available information on local currents and previous studies, support the conclusion that the dispersion of farm wastes over large areas (spanning kilometres) are responsible for the elevated delta(15)N signatures found in the FA meadow area. Despite this, no changes in meadow structure were detected and only some changes at the level of seagrass community (epiphytes abundances and herbivores activity) could be interpreted at the light of nutrient-induced effects in the FA area. Results from this study indicate that concentrating aquaculture facilities in off-shore areas is a strategy not totally exempt of environmental risk on near-shore sensitive habitats such as seagrass meadows.

  13. AshMeadowsSpeckledDace_CH

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify the areas where final critical habitat for the Ash Meadows Amargosa pupfish (Cyprinodon nevadensis mionectes) occur. "Nevada, Nye County: Each of...

  14. AshMeadowsAmargosaPupfish_CH

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify the areas where final critical habitat for the Ash Meadows Amargosa pupfish (Cyprinodon nevadensis mionectes) occur. "Nevada, Nye County: Each of...

  15. AshMeadowsSpeckledDace_CH

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify the areas where final critical habitat for the Ash Meadows Amargosa pupfish (Cyprinodon nevadensis mionectes) occur. "Nevada, Nye County: Each of...

  16. AshMeadowsAmargosaPupfish_CH

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify the areas where final critical habitat for the Ash Meadows Amargosa pupfish (Cyprinodon nevadensis mionectes) occur. "Nevada, Nye County: Each of...

  17. Meadow soil microbiocoenosis under influence of railway transport

    Directory of Open Access Journals (Sweden)

    N. J. Bobryk

    2012-07-01

    Full Text Available A case study of the microbial coenosis status of the soil of meadow ecosystem at different distances from the railway track was carried out in the urbansettlement Velykyi Bereznyi in the Transcarpathian Region. The increasing technogenic pollution causes changes in the complex of microbiological indices, brings about qualitative and quantitative changes in the functioning of microbial cenosis of the soil. That has a negative impact on its potential fertility, and raises phytotoxic levels in soils. The results show that soils phytotoxic hyperactivity of ecosystems along the mainline correlates with the quantity of actinomycetes, coliforms, oligonitrophilc and cryptogamous microorgamisms.

  18. Seagrass meadows in a globally changing environment.

    Science.gov (United States)

    Unsworth, Richard K F; van Keulen, Mike; Coles, Rob G

    2014-06-30

    Seagrass meadows are valuable ecosystem service providers that are now being lost globally at an unprecedented rate, with water quality and other localised stressors putting their future viability in doubt. It is therefore critical that we learn more about the interactions between seagrass meadows and future environmental change in the anthropocene. This needs to be with particular reference to the consequences of poor water quality on ecosystem resilience and the effects of change on trophic interactions within the food web. Understanding and predicting the response of seagrass meadows to future environmental change requires an understanding of the natural long-term drivers of change and how these are currently influenced by anthropogenic stress. Conservation management of coastal and marine ecosystems now and in the future requires increased knowledge of how seagrass meadows respond to environmental change, and how they can be managed to be resilient to these changes. Finding solutions to such issues also requires recognising people as part of the social-ecological system. This special issue aims to further enhance this knowledge by bringing together global expertise across this field. The special issues considers issues such as ecosystem service delivery of seagrass meadows, the drivers of long-term seagrass change and the socio-economic consequences of environmental change to seagrass.

  19. 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.

  20. 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...

  1. 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.

  2. Variation in phenology of hibernation and reproduction in the endangered New Mexico meadow jumping mouse (Zapus hudsonius luteus

    Directory of Open Access Journals (Sweden)

    Jennifer K. Frey

    2015-08-01

    Full Text Available Hibernation is a key life history feature that can impact many other crucial aspects of a species’ biology, such as its survival and reproduction. I examined the timing of hibernation and reproduction in the federally endangered New Mexico meadow jumping mouse (Zapus hudsonius luteus, which occurs across a broad range of latitudes and elevations in the American Southwest. Data from museum specimens and field studies supported predictions for later emergence and shorter active intervals in montane populations relative to lower elevation valley populations. A low-elevation population located at Bosque del Apache National Wildlife Refuge (BANWR in the Rio Grande valley was most similar to other subspecies of Z. hudsonius: the first emergence date was in mid-May and there was an active interval of 162 days. In montane populations of Z. h. luteus, the date of first emergence was delayed until mid-June and the active interval was reduced to ca 124–135 days, similar to some populations of the western jumping mouse (Z. princeps. Last date of immergence into hibernation occurred at about the same time in all populations (mid to late October. In montane populations pregnant females are known from July to late August and evidence suggests that they have a single litter per year. At BANWR two peaks in reproduction were expected based on similarity of active season to Z. h. preblei. However, only one peak was clearly evident, possibly due to later first reproduction and possible torpor during late summer. At BANWR pregnant females are known from June and July. Due to the short activity season and geographic variation in phenology of key life history events of Z. h. luteus, recommendations are made for the appropriate timing for surveys for this endangered species.

  3. Variation in phenology of hibernation and reproduction in the endangered New Mexico meadow jumping mouse (Zapus hudsonius luteus).

    Science.gov (United States)

    Frey, Jennifer K

    2015-01-01

    Hibernation is a key life history feature that can impact many other crucial aspects of a species' biology, such as its survival and reproduction. I examined the timing of hibernation and reproduction in the federally endangered New Mexico meadow jumping mouse (Zapus hudsonius luteus), which occurs across a broad range of latitudes and elevations in the American Southwest. Data from museum specimens and field studies supported predictions for later emergence and shorter active intervals in montane populations relative to lower elevation valley populations. A low-elevation population located at Bosque del Apache National Wildlife Refuge (BANWR) in the Rio Grande valley was most similar to other subspecies of Z. hudsonius: the first emergence date was in mid-May and there was an active interval of 162 days. In montane populations of Z. h. luteus, the date of first emergence was delayed until mid-June and the active interval was reduced to ca 124-135 days, similar to some populations of the western jumping mouse (Z. princeps). Last date of immergence into hibernation occurred at about the same time in all populations (mid to late October). In montane populations pregnant females are known from July to late August and evidence suggests that they have a single litter per year. At BANWR two peaks in reproduction were expected based on similarity of active season to Z. h. preblei. However, only one peak was clearly evident, possibly due to later first reproduction and possible torpor during late summer. At BANWR pregnant females are known from June and July. Due to the short activity season and geographic variation in phenology of key life history events of Z. h. luteus, recommendations are made for the appropriate timing for surveys for this endangered species.

  4. Restore McComas Meadows; Meadow Creek Watershed, 2005-2006 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    McRoberts, Heidi (Nez Perce Tribe, Department of Fisheries Resource Management, Lapwai, ID)

    2006-07-01

    The Nez Perce Tribe Department of Fisheries Resource Management, Watershed Division approaches watershed restoration with a ridge-top to ridge-top approach. Watershed restoration projects within the Meadow Creek watershed are coordinated and cost shared with the Nez Perce National Forest. The Nez Perce Tribe began watershed restoration projects within the Meadow Creek watershed of the South Fork Clearwater River in 1996. Progress has been made in restoring the watershed by excluding cattle from critical riparian areas through fencing, planting trees in riparian areas within the meadow and its tributaries, prioritizing culverts for replacement to accommodate fish passage, and decommissioning roads to reduce sediment input. During this contract period work was completed on two culvert replacement projects; Doe Creek and a tributary to Meadow Creek. Additionally construction was also completed for the ditch restoration project within McComas Meadows. Monitoring for project effectiveness and trends in watershed conditions was also completed. Road decommissioning monitoring, as well as stream temperature, sediment, and discharge were completed.

  5. Relations between Carbon Dioxide Fluxes and Environmental Factors of Kobresia humilis Meadows and Potentilla fruticosa Meadows

    Institute of Scientific and Technical Information of China (English)

    ZHAO Liang; XU Shixiao; LI Yingnian; TANG Yanbong; ZHAO Xinquan; GU Song; DU Mingyuan; YU Guirui

    2007-01-01

    Carbon dioxide fluxes of Kobresia humilis and Potentillafruticosa shrub meadows,two typical ecosystems in the Qinghai-Tibet Plateau,were measured by eddy covariance technology and the data collected in August 2003 were employed to analyze the relations between carbon dioxide fluxes and environmental factors of the ecosystems.August is the time when the two ecosystems reach their peak leaf area indexes and stay stable,and also the period when the net carbon absorptions of Kobresia humilis and Potentilla photo flux densities (PPFD),the carbon dioxide-uptake rate of the Kobresia humilis meadow is higher than that of the Potentilla fruticosa shrub meadow;where the PPFD are rates of the two ecosystems declined as air temperature increased,but the carbon dioxide uptake rate of the Kobresia humilis meadow decreased more quickly (-0.086) than that of the Potentilla fruticosa shrub meadow (-0.016).Soil moistures exert influence on the soil respirations and this varies with the vegetation type.The daily carbon dioxide absorptions of the ecosystems increase with increased diurnal temperature differences and higher diurnal temperature differences result in higher carbon dioxide exchanges.There exists a negative correlation between the vegetation albedos and the carbon dioxide fluxes.

  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. Stability of alpine meadow ecosystem on the Qinghai- Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    ZHOU Huakun; ZHOU Li; ZHAO Xinquan; LIU Wei; LI Yingnian; GU Song; ZHOU Xinmin

    2006-01-01

    The meadow ecosystem on the Qinghai-Tibetan Plateau is considered to be sensitive to climate change. An understanding of the alpine meadow ecosystem is therefore important for predicting the response of ecosystems to climate change. In this study, we use the coefficients of variation (Cv) and stability (E) obtained from the Haibei Alpine Meadow Ecosystem Research Station to characterize the ecosystem stability. The results suggest that the net primary production of the alpine meadow ecosystem was more stable (Cv = 13.18%) than annual precipitation (Cv = 16.55%) and annual mean air temperature (Cv = 28.82%). The net primary production was insensitive to either the precipitation (E = 0.0782) or air temperature (E = 0.1113). In summary, the alpine meadow ecosystem on the Qinghai- Tibetan Plateau is much stable. Comparison of alpine meadow ecosystem stability with other five natural grassland ecosystems in Israel and southern African indicates that the alpine meadow ecosystem on the Qinghai-Tibetan Plateau is the most stable ecosystem. The alpine meadow ecosystem with relatively simple structure has high stability, which indicates that community stability is not only correlated with biodiversity and community complicity but also with environmental stability. An average oscillation cycles of 3―4 years existed in annual precipitation, annual mean air temperature, net primary production and the population size of consumers at the Haibei natural ecosystem. The high stability of the alpine meadow ecosystem may be resulting also from the adaptation of the ecosystem to the alpine environment.

  8. Quantifying Volume of Groundwater in High Elevation Meadows

    Science.gov (United States)

    Ciruzzi, D.; Lowry, C.

    2013-12-01

    Assessing the current and future water needs of high elevation meadows is dependent on quantifying the volume of groundwater stored within the meadow sediment. As groundwater dependent ecosystems, these meadows rely on their ability to capture and store water in order to support ecologic function and base flow to streams. Previous research of these meadows simplified storage by assuming a homogenous reservoir of constant thickness. These previous storage models were able to close the water mass balance, but it is unclear if these assumptions will be successful under future anthropogenic impacts, such as increased air temperature resulting in dryer and longer growing seasons. Applying a geophysical approach, ground-penetrating radar was used at Tuolumne Meadows, CA to qualitatively and quantitatively identify the controls on volume of groundwater storage. From the geophysical results, a three-dimensional model of Tuolumne Meadows was created, which identified meadow thickness and bedrock geometry. This physical model was used in a suite of numerical models simulating high elevation meadows in order to quantify volume of groundwater stored with temporal and spatial variability. Modeling efforts tested both wet and dry water years in order to quantify the variability in the volume of groundwater storage for a range of aquifer properties. Each model was evaluated based on the seasonal depth to water in order to evaluate a particular scenario's ability to support ecological function and base flow. Depending on the simulated meadows ability or inability to support its ecosystem, each representative meadow was categorized as successful or unsuccessful. Restoration techniques to increase active storage volume were suggested at unsuccessful meadows.

  9. The effects of Pleistocene climate change on biotic differentiation in a montane songbird clade from Wallacea.

    Science.gov (United States)

    Ng, Nathaniel S R; Wilton, Peter R; Prawiradilaga, Dewi Malia; Tay, Ywee Chieh; Indrawan, Mochamad; Garg, Kritika M; Rheindt, Frank E

    2017-09-01

    The role of Pleistocene Ice Age in tropical diversification is poorly understood, especially in archipelagos, in which glaciation-induced sea level fluctuations may lead to complicated changes in land distribution. To assess how Pleistocene land bridges may have facilitated gene flow in tropical archipelagos, we investigated patterns of diversification in the rarely-collected rusty-bellied fantail Rhipidura teysmanni (Passeriformes: Rhipiduridae) complex from Wallacea using a combination of bioacoustic traits and whole-genome sequencing methods (dd-RADSeq). We report a biogeographic leapfrog pattern in the vocalizations of these birds, and uncover deep genomic divergence among island populations despite the presence of intermittent land connections between some. We demonstrate how rare instances of genetic introgression have affected the evolution of this species complex, and document the presence of double introgressive mitochondrial sweeps, highlighting the dangers of using only mitochondrial DNA in evolutionary research. By applying different tree inference approaches, we demonstrate how concatenation methods can give inaccurate results when investigating divergence in closely-related taxa. Our study highlights high levels of cryptic avian diversity in poorly-explored Wallacea, elucidates complex patterns of Pleistocene climate-mediated diversification in an elusive montane songbird, and suggests that Pleistocene land bridges may have accounted for limited connectivity among montane Wallacean biota. Copyright © 2017 Elsevier Inc. All rights reserved.

  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. Posidonia oceanica L. (Delile) Meadow from Messioua

    OpenAIRE

    Sammari, Ch.; Hattour, A.; Komatsu, T; Zarrouk, S; Ben Mustapha, K.; El Abed, A.

    2002-01-01

    In order to study the benthic ecology of the “Messioua banc” (30 NM east off Zarzis, Southern Tunisia), a traditional Tunisian sponge fishing ground, four marine campaigns were conducted with the R/V “Hannibal” from October 2000 to August 2001. The objectives of three of these campaigns were field validation, focusing on the sampling of the Posidonia oceanica meadow and of the sponge population. However the goal of the fourth one, with the use of a multi-beam sonar SEABAT 9001 (Reson Co.), wa...

  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 mea

  13. Development-Induced Displacement in Romania: the Case of Roşia Montană Mining Project

    Directory of Open Access Journals (Sweden)

    Lucian VESALON

    2012-06-01

    Full Text Available This paper proposes a critical discussion of the population displacement processes involved in the Roşia Montană gold-mining project within the theoretical framework of development-induced displacement (DID. We begin with an overview of the geographical context of the rural community, focusing on the social and economic structure of Roşia Montană. After assessing the relocation and resettlement processes, we examine several problems related to the compensation mechanism set up by the mining company. The aim of the research is to highlight the complexity of the consequences of development-induced displacement and the limits of the policies of relocation and resettlement in the area.

  14. Taxonomic and functional ecology of montane ants

    Directory of Open Access Journals (Sweden)

    Tom Rhys Bishop

    2017-04-01

    Full Text Available Why is biological diversity distributed in the way that it is? This question has been central to ecology and biogeography for centuries and is of great importance for pure and applied reasons. I use a functional trait view of ecology to complement standard sampling protocols to better understand the distribution and structure of ant (Hymenoptera: Formicidae diversity across mountains. I use a long-term dataset of ant diversity and abundance, combined with a recently collected morphological trait dataset to examine how the alpha and beta diversity of ants responds to changes in temperature along an extensive elevational gradient in southern Africa. In addition, I link morphological thermoregulatory traits to each other and to the environment with a new database of ant elevational abundances from across the globe. Finally, I analyse how physiological thermal tolerances vary and constrain foraging patterns in montane ants. I find that temperature is a strong driver of both alpha and beta diversity patterns. In addition, morphological traits such as colour and body size are found to have a significant relationship to ambient temperatures. This relationship also implies that the relative abundances of different ant species change depending on their thermoregulatory traits (colour and body size and the surrounding thermal environment. Furthermore, the critical thermal minimum (CTmin of the ant species investigated and the lowest environmental temperatures are found to be key in constraining foraging activity patterns. The data presented here strengthen and link existing ideas about how thermoregulation can influence ecological communities and also suggests important ways in which diversity patterns may change in the future.

  15. Montane and cloud forest specialists among neotropical Xylaria species

    Science.gov (United States)

    D. Jean Lodge; Thomas L& #230; ss& #248; e; M. Catherine Aime; Terry W. Henkel; M. Catherine Aime; Terry W. Henkel

    2008-01-01

    We compared recored of neotropical Xylaria species among Belize, Ecuador, the Guianas, Mexico, Puerto Rico and Venezuela to determine if there were neotropical taxa consistently found only in cloud forest or high montane forests that might be endangered by climate change.

  16. Evaluation of management practices in wetland meadows at Grays Lake National Wildlife Refuge, Idaho, 1997-2000

    Science.gov (United States)

    Austin, J.E.; Pyle, W.H.; Keough, J.R.; Johnson, D.H.

    2002-01-01

    experimental units, the most common were American coot, sandhill crane, Canada goose, American avocet, mallard, and cinnamon teal. Daily survival rates (DSRs) of dabbling duck nests (all species pooled) were negatively affected by fall grazing. We detected no effects of treatments on DSRs of Canada geese or sandhill crane nests. DSRs for sandhill crane nests were higher in 1998 than in 1999 or 2000 and were slightly higher than that in 1997. DSRs for coot nests were affected by both year and treatment; within-treatment differences among years were extensive, In 1998, when all units were idled, DSRs for coot nests were higher in units assigned to idle treatment than those assigned to fall-grazed or rotation treatment. DSRs for coot nests did not differ among treatment blocks in 1997 (all units idled) or 1999 (first year after treatments). We speculate that compaction of residual vegetation by snowpack reduced any differences between idle and treated units and thus lessened the value of idle habitat for most nesting birds. Nesting densities and nest success rates of Canada geese, dabbling ducks, and sandhill cranes were lower those that reported from Steel's (1952) study in 1949-1950, but differences in habitats and areas searched relative to our study make comparisons difficult. Nest success rates of sandhill cranes also were lower than those reported by Drewien (1973). Declines in nest success probably are related to changes in predator community. We captured 5 species of small mammals (meadow vole, montane vole, deer mouse, vagrant shrew, and ermine). Populations of meadow and montane voles irrupted in 1998 then crashed in spring 1999; the most marked changes were in montane vole numbers. Capture rates of ermine and observation rates for striped skunks and raptors suggested a numerical response (higher recruitment) by these predators to higher prey abundance and possibly distributional shifts (movement into areas of more abundant microtines). We did not detect differences

  17. 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

  18. Selective Extraction Methods for Aluminium, Iron and Organic Carbon from Montane Volcanic Ash Soils

    Institute of Scientific and Technical Information of China (English)

    B. JANSEN; F. H. TONNEIJCK; J. M. VERSTRATEN

    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 A1 and Fe in stabilizing organic matter in volcanic ash soils,we assessed various extraction methods of A1,Fe,and C fractions from montane volcanic ash soils in northern Ecuador,aiming at elucidating the role of A1 and Fe in stabilizing soil organic matter (SOM).We found extractions with cold sodium hydroxide,ammonium oxalate/oxalic acid,sodium pyrophosphate,and sodium tetraborate to be particularly useful.Combination of these methods yielded information about the role of the mineral phase in stabilizing organic matter and the differences in type and degree of complexation of organic matter with Al and Fe in the various horizons and soil profiles.Sodium tetraborate extraction proved the only soft extraction method that yielded simultaneous information about the Al,Fe,and C fractions extracted.It also appeared to differentiate between SOM fractions of different stability.The fractions of copper chloride- and potassium chloride-extractable A1 were useful in assessing the total reactive and toxic Al fractions,respectively.The classical subdivision of organic matter into humic acids,fulvic acids,and humin added little useful information.The use of fulvic acids as a proxy for mobile organic matter as done in several model-based approaches seems invalid in the soils studied.

  19. 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.

  20. Microhabitat differences impact phylogeographic concordance of codistributed species: genomic evidence in montane sedges (Carex L.) from the Rocky Mountains.

    Science.gov (United States)

    Massatti, Rob; Knowles, L Lacey

    2014-10-01

    By selecting codistributed, closely related montane sedges from the Rocky Mountains that are similar in virtually all respects but one-their microhabitat affinities-we test predictions about how patterns of genetic variation are expected to differ between Carex nova, an inhabitant of wetlands, and Carex chalciolepis, an inhabitant of drier meadows, slopes, and ridges. Although contemporary populations of the taxa are similarly isolated, the distribution of glacial moraines suggests that their past population connectedness would have differed. Sampling of codistributed population pairs from different mountain ranges combined with the resolution provided by over 24,000 single nucleotide polymorphism loci supports microhabitat-mediated differences in the sedges' patterns of genetic variation that are consistent with their predicted differences in the degree of isolation of ancestral source populations. Our results highlight how microhabitat preferences may interact with glaciations to produce fundamental differences in the past distributions of presently codistributed species. We discuss the implications of these findings for generalizing the impacts of climate-induced distributional shifts for communities, as well as for the prospects of gaining insights about species-specific deterministic processes, not just deterministic community-level responses, from comparative phylogeographic study.

  1. Great Meadows National Wildlife Refuge : Narrative Report : January - Decemeber 1974

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows NWR and satellite refuges outlines refuge accomplishments during the 1974 calendar year. The report begins by...

  2. Narrative Report : Calendar Year 1969 : Great Meadows National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during the 1969 calendar year. The report begins by...

  3. Narrative Report : Fiscal Year 1975 : Great Meadows National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows NWR and satellite refuges outlines refuge accomplishments during the 1975 fiscal year. The report begins by...

  4. Ash Meadows National Wildlife Refuge : A plan for the future

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The management plan is to maintain Ash Meadows Refuge as a natural ecosystem. To accomplish this, the area will be restored as much as possible to conditions which...

  5. Crane Meadows National Wildlife Refuge: Comprehensive Conservation Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Comprehensive Conservation Plan (CCP) was written to guide management on Crane Meadows NWR for the next 15 years. This plan outlines the Refuge vision and...

  6. Great Meadows National Wildlife Refuge: Final Comprehensive Conservation Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Comprehensive Conservation Plan (CCP) was written to guide management on Great Meadows NWR for the next 15 years. This plan outlines the Refuge vision and...

  7. Great Meadows National Wildlife Refuge Monthly Narrative: February 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments February 1993. The report begins with a summary of the...

  8. Great Meadows National Wildlife Refuge Monthly Narrative: March 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during March 1993. The report begins with a summary of the...

  9. Great Meadows National Wildlife Refuge Monthly Narrative: August 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during August 1993. The report begins with a summary of the...

  10. Great Meadows National Wildlife Refuge Monthly Narrative: January 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during January 1993. The report begins with a summary of the...

  11. Great Meadows National Wildlife Refuge Monthly Narrative: April 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during April 1993. The report begins with a summary of the...

  12. Great Meadows National Wildlife Refuge Monthly Narrative: June 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during June 1993. The report begins with a summary of the...

  13. Great Meadows National Wildlife Refuge Monthly Narrative: September 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during September 1993. The report begins with a summary of...

  14. Great Meadows National Wildlife Refuge Monthly Narrative: July 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during July 1993. The report begins with a summary of the...

  15. Experimental infection of meadow voles (Microtus pennsylvanicus) with sheep scrapie

    Science.gov (United States)

    Carlson, CM; Schneider, Jay R.; Pedersen, Janice C.; Heisey, Dennis M.; Johnson, Christopher J.

    2015-01-01

    Meadow voles (Microtus pennsylvanicus) are permissive to chronic wasting disease (CWD) infection, but their susceptibility to other transmissible spongiform encephalopathies (TSEs) is poorly characterized. In this initial study, we intracerebrally challenged 6 meadow voles with 2 isolates of sheep scrapie. Three meadow voles acquired a TSE after the scrapie challenge and an extended incubation period. The glycoform profile of proteinase K-resistant prion protein (PrP(res)) in scrapie-sick voles remained similar to the sheep inocula, but differed from that of voles clinically affected by CWD. Vacuolization patterns and disease-associated prion protein (PrP(Sc)) deposition were generally similar in all scrapie-affected voles, except in the hippocampus, where PrP(Sc) staining varied markedly among the animals. Our results demonstrate that meadow voles can acquire a TSE after intracerebral scrapie challenge and that this species could therefore prove useful for characterizing scrapie isolates.

  16. Experimental infection of meadow voles (Microtus pennsylvanicus) with sheep scrapie.

    Science.gov (United States)

    Carlson, Christina M; Schneider, Jay R; Pedersen, Joel A; Heisey, Dennis M; Johnson, Christopher J

    2015-01-01

    Meadow voles (Microtus pennsylvanicus) are permissive to chronic wasting disease (CWD) infection, but their susceptibility to other transmissible spongiform encephalopathies (TSEs) is poorly characterized. In this initial study, we intracerebrally challenged 6 meadow voles with 2 isolates of sheep scrapie. Three meadow voles acquired a TSE after the scrapie challenge and an extended incubation period. The glycoform profile of proteinase K-resistant prion protein (PrP(res)) in scrapie-sick voles remained similar to the sheep inocula, but differed from that of voles clinically affected by CWD. Vacuolization patterns and disease-associated prion protein (PrP(Sc)) deposition were generally similar in all scrapie-affected voles, except in the hippocampus, where PrP(Sc) staining varied markedly among the animals. Our results demonstrate that meadow voles can acquire a TSE after intracerebral scrapie challenge and that this species could therefore prove useful for characterizing scrapie isolates.

  17. Narrative Report : Great Meadows National Wildlife Refuge : May - August 1959

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments from May through August of 1959. The report begins by summarizing...

  18. The Trail Inventory of Ash Meadows NWR [Cycle 2

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this report is to create a baseline inventory of all non-motorized trails on Ash Meadows National Wildlife Refuge. Trails in this inventory are...

  19. Great Meadows National Wildlife Refuge : Narrative Report : May - August 1963

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments from May through August of 1963. The report begins by summarizing...

  20. Great Meadows National Wildlife Refuge : Narrative Report : May - August 1962

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments from May through August of 1962. The report begins by summarizing...

  1. Narrative Report : Calendar Year 1968 : Great Meadows National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during the 1968 calendar year. The report begins by...

  2. Great Meadows National Wildlife Refuge (Sudbury Division) [Land Status Map

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This map was produced by the Division of Realty to depict landownership at Great Meadows National Wildlife Refuge. It was generated from rectified aerial...

  3. Great Meadows National Wildlife Refuge Monthly Narrative: May 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during May 1993. The report begins with a summary of the...

  4. Ash Meadows Pupfish Preserve: A proposal from The Nature Conservancy

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Ash Meadows region of southwest Nevada has evolved since the last period of glaciation into a unique alkali desert ecosystem. The remnant springs, pools and...

  5. 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.

  6. 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.

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

    OpenAIRE

    Chaverri, Gloriana; Garin, Inazio; Alberdi, Antton; Jimenez, Lide; Castillo-Salazar, Cristian; Aihartza, Joxerra

    2016-01-01

    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 ...

  8. 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.

  9. Photosynthetic activity buffers ocean acidification in seagrass meadows

    Directory of Open Access Journals (Sweden)

    I. E. Hendriks

    2013-07-01

    Full Text Available Macrophytes growing in shallow coastal zones characterized by intense metabolic activity have the capacity to modify pH within their canopy and beyond. We observed diel pH ranges is in shallow (5–12 m seagrass (Posidonia oceanica meadows from 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 and max pHNBS and max ΩAr. Oxygen production positively influenced the range and maximum pHNBS and the range of ΩAr. In June, vertical mixing (as Turbulent Kinetic Energy influenced ΩAr, while in September there was no effect of hydrodynamics on the carbonate system within the canopy. ΩAr was positively correlated with the calcium carbonate load of the leaves, demonstrating a direct link between structural parameters, ΩAr and carbonate deposition. There was a direct relationship between ΩAr, influenced directly by meadow LAI, and CaCO3 content of the leaves. Therefore, calcifying organisms, e.g. epiphytes with carbonate skeletons, might benefit from the modification of the carbonate system by the meadow. The meadow might be capable of providing refugia for calcifiers by increasing pH and ΩAr through metabolic activity. There is, however, concern for the ability of seagrasses to provide this refugia function 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, both strongly linked to LAI. Organisms associated with seagrass communities may therefore suffer from the loss of pH buffering capacity in degraded meadows.

  10. 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.

  11. Spatio-temporal variability of Borer Polychaetes in Posidonia oceanica beds and its relation to meadow structure

    Directory of Open Access Journals (Sweden)

    C. VASAPOLLO

    2015-01-01

    Full Text Available Posidonia oceanica forms an extremely productive and complex ecosystem in the coastal Mediterranean Sea providing a suitable habitat for hundreds of plant and animal species. Among motile invertebrates associated to Posidonia meadows,  polychaete borers of the plant sheaths represent a unique group which exploit a peculiar microhabitat. They belong to the family Eunicidae with three dominant species, Lysidice collaris, L. ninetta and L. unicornis. Due to their strong association with Posidonia shoots, these animals are particularly suitable to study the plant and animal spatial relationships and their pattern of variability. The aim of this work was to evaluate the frequency of occurrence of these animals (Index of Borer, IB at different spatial and temporal (summer vs winter scales in two Posidonia meadows off the Ischia Island (Gulf of Naples, Italy, which are exposed to different degrees of human impact and of hydrological conditions. Results showed IB values of L. collaris (the most abundant species significantly different between meadows and at scales from 10s to 100s of meters, as well as between summer and winter. The IB of L. ninetta showed significant differences only at scales of 10s of meters while, on the contrary, the IB of L. unicornis (the less abundant species did not show variability at any spatial and temporal scales. Most of the variance was at the more impacted and less water movement exposed meadow, suggesting higher level of small and intermediate scales of patchiness of borers at this meadow. These variation patterns  are discussed in relation  to local environmental differences between the studied Posidonia beds.

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

    Science.gov (United States)

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

    2016-03-01

    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.

  13. 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.

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

    Science.gov (United States)

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

    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.

  15. Subalpine meadow plant communities in Yosemite and Sequoia and Kings Canyon National Parks, 2011-2012

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This publication presents data collected within meadows from samples used to assess meadow plant community responses to recreational pack stock as part of a USGS...

  16. Community characteristics of tropical montane evergreen forest and tropical montane dwarf forest in Bawangling National Nature Reserve on Hainan Island, South China

    OpenAIRE

    Wenxing Long; Runguo Zang; Yi Ding

    2011-01-01

    Both tropical montane evergreen forest (TMEF) and tropical montane dwarf forest (TMDF) are typical tropical cloud forests on Hainan Island. To compare community structure and species diversity be-tween these two forest types, we established eight and ten plots (each with 2,500 m2 in area) in TMEF and TMDF, respectively, in Bawangling National Nature Reserve on Hainan Island, South China. We investigated each individual plant with diameter at breast height (DBH) ≥1 cm including trees, shrubs a...

  17. Population structure and secondary production of Siriella clausii, a dominant detritus feeding mysid in Posidonia oceanica meadows (W Mediterranean Sea)

    OpenAIRE

    Barberá Cebrián, Carmen; Sanchez-Jerez, Pablo; Sorbe, Jean Claude

    2013-01-01

    Temporal trends in abundance, demographic structure of the population and secondary production of Siriella clausii were studied at three different sectors of Posidonia oceanica meadows in the SE Iberian Peninsula, with different levels of habitat complexity. Secondary production was calculated through three methods widely employed in marine invertebrates: the Hynes method (based on demographic structure data) and models by Morin-Bourassa and Brey (based on biomass data). This filter/grazer an...

  18. RELATIONSHIPS OF MEADOW VEGETATION TO GROUNDWATER DEPTH: EFFECTS OF PRECIPITATION VARIABILITY AND STREAM INCISION

    Science.gov (United States)

    The composition of riparian meadow vegetation is controlled by access to groundwater. Depth to groundwater is controlled by meadow architecture and water source, and changes in either meadow architecture or water source through stream incision or changes in annual precipitation c...

  19. 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.

  20. Echo Meadows Project Winter Artificial Recharge.

    Energy Technology Data Exchange (ETDEWEB)

    Ziari, Fred

    2002-12-19

    This report discusses the findings of the Echo Meadows Project (BPA Project 2001-015-00). The main purpose of this project is to artificially recharge an alluvial aquifer, WITH water from Umatilla River during the winter high flow period. In turn, this recharged aquifer will discharge an increased flow of cool groundwater back to the river, thereby improving Umatilla River water quality and temperature. A considerable side benefit is that the Umatilla River should improve as a habitat for migration, spanning, and rearing of anadromous and resident fish. The scope of this project is to provide critical baseline information about the Echo Meadows and the associated reach of the Umatilla River. Key elements of information that has been gathered include: (1) Annual and seasonal groundwater levels in the aquifer with an emphasis on the irrigation season, (2) Groundwater hydraulic properties, particularly hydraulic conductivity and specific yield, and (3) Groundwater and Umatilla River water quality including temperature, nutrients and other indicator parameters. One of the major purposes of this data gathering was to develop input to a groundwater model of the area. The purpose of the model is to estimate our ability to recharge this aquifer using water that is only available outside of the irrigation season (December through the end of February) and to estimate the timing of groundwater return flow back to the river. We have found through the data collection and modeling efforts that this reach of the river had historically returned as much as 45 cubic feet per second (cfs) of water to the Umatilla River during the summer and early fall. However, this return flow was reduced to as low as 10 cfs primarily due to reduced quantities of irrigation application, gain in irrigation efficiencies and increased groundwater pumping. Our modeling indicated that it is possible to restore these critical return flows using applied water outside of the irrigation season. We further

  1. Echo Meadows Project Winter Artificial Recharge.

    Energy Technology Data Exchange (ETDEWEB)

    Ziari, Fred

    2002-12-19

    This report discusses the findings of the Echo Meadows Project (BPA Project 2001-015-00). The main purpose of this project is to artificially recharge an alluvial aquifer, WITH water from Umatilla River during the winter high flow period. In turn, this recharged aquifer will discharge an increased flow of cool groundwater back to the river, thereby improving Umatilla River water quality and temperature. A considerable side benefit is that the Umatilla River should improve as a habitat for migration, spanning, and rearing of anadromous and resident fish. The scope of this project is to provide critical baseline information about the Echo Meadows and the associated reach of the Umatilla River. Key elements of information that has been gathered include: (1) Annual and seasonal groundwater levels in the aquifer with an emphasis on the irrigation season, (2) Groundwater hydraulic properties, particularly hydraulic conductivity and specific yield, and (3) Groundwater and Umatilla River water quality including temperature, nutrients and other indicator parameters. One of the major purposes of this data gathering was to develop input to a groundwater model of the area. The purpose of the model is to estimate our ability to recharge this aquifer using water that is only available outside of the irrigation season (December through the end of February) and to estimate the timing of groundwater return flow back to the river. We have found through the data collection and modeling efforts that this reach of the river had historically returned as much as 45 cubic feet per second (cfs) of water to the Umatilla River during the summer and early fall. However, this return flow was reduced to as low as 10 cfs primarily due to reduced quantities of irrigation application, gain in irrigation efficiencies and increased groundwater pumping. Our modeling indicated that it is possible to restore these critical return flows using applied water outside of the irrigation season. We further

  2. Hydrologic and hydraulic analyses of Great Meadow wetland, Acadia National Park, Maine

    Science.gov (United States)

    Lombard, Pamela J.

    2017-01-26

    The U.S. Geological Survey completed hydrologic and hydraulic analyses of Cromwell Brook and the Sieur de Monts tributary in Acadia National Park, Maine, to better understand causes of flooding in complex hydrologic and hydraulic environments, like those in the Great Meadow wetland and Sieur de Monts Spring area. Regional regression equations were used to compute peak flows with from 2 to 100-year recurrence intervals at seven locations. Light detection and ranging data were adjusted for bias caused by dense vegetation in the Great Meadow wetland; and then combined with local ground surveys used to define the underwater topography and hydraulic structures in the study area. Hydraulic modeling was used to evaluate flood response in the study area to a variety of hydrologic and hydraulic scenarios.Hydraulic modeling indicates that enlarging the culvert at Park Loop Road could help mitigate flooding near the Sieur de Monts Nature Center that is caused by streamflows with large recurrence intervals; however, hydraulic modeling also indicates that the Park Loop Road culvert does not aggravate flooding near the Nature Center caused by the more frequent high intensity rainstorms. That flooding is likely associated with overland flow resulting from (1) quick runoff from the steep Dorr Mountain hitting the lower gradient Great Meadow wetland area and (2) poor drainage aggravated by beaver dams holding water in the wetland.Rapid geomorphic assessment data collected in June 2015 and again in April 2016 indicate that Cromwell Brook has evidence of aggradation, degradation, and channel widening throughout the drainage basin. Two of five reference cross sections developed for this report also indicate channel aggradation.

  3. 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.

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

    Science.gov (United States)

    Chaverri, Gloriana; Garin, Inazio; Alberdi, Antton; Jimenez, Lide; Castillo-Salazar, Cristian; Aihartza, Joxerra

    2016-01-01

    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. PMID:27706168

  5. Nutrient supply in undrained and drained Calthion meadows

    NARCIS (Netherlands)

    van Duren, IC; Pegtel, DM; Aerts, BA; Inberg, JA

    1997-01-01

    Plant species-rich Calthion meadows on mesotrophic fen pear soil extensively cut for hay are among the endangered semi-natural vegetation types in northwestern Europe. They are often badly affected by lowering the groundwater table (drainage) and fertilization. In a comparative study of an undrained

  6. 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.

  7. 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.

  8. Studies on Fast Remediation of Soda Meadow Alkaline Soil

    Institute of Scientific and Technical Information of China (English)

    ZHOU Lianren; SUN Yankun; LI Dawei

    2010-01-01

    Researches on models of remediation quickly in soda meadow alkaline soil, and dynamic variation of water-salt in saline soil of Zhaozhou County were studied systematically from 2001 to 2006. Realize the vegetation cover of those years through the artificial planting, mixed seeding lymc grass (Elymus dahuricus Turcz) and melilot in the mode of rotary tillage and deep loosening in lower and medium saline soils. The results showed that there was remarkable relationship between net evaporation (difference of precipitation and evaporation) and total salt content in the soil. The net evaporation could be used as a new method to forecast the dynamics variation of salt to ensure the pasture optimum sowing time. Realize the autumnal vegetation cover of those years through direct planting on the bourgeon layer of soda meadow alkaline soil, on the other hand, the covered pasture made the function of restraining salt and alkaline content to realize the biology reverse succession quickly. Forage seeds were seeded directly on the seeding bed of soda alkaline meadow at the end of July. In fall of the same year, a certain amount of biomass was obtained. The model, which has remarkable economical efficiency and use widely, represented the innovative model for the fast vegetation restoration on the soda alkaline meadow soil.

  9. Seagrass meadows as a globally significant carbonate reservoir

    Science.gov (United States)

    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, C. M.

    2015-08-01

    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 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 emissions from precipitation, seagrass meadows are still strong CO2 sinks as demonstrated by the comparison of carbon (PIC and POC) stocks between vegetated and adjacent un-vegetated sediments.

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

    Science.gov (United States)

    Röhr, Maria Emilia; Boström, Christoffer; Canal-Vergés, Paula; Holmer, Marianne

    2016-11-01

    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 in Finland and 10 in Denmark to explore seagrass carbon stocks (Corg stock) and carbon accumulation rates (Corg 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. The Corg stock integrated over the top 25 cm of the sediment averaged 627 g C m-2 in Finland, while in Denmark the average Corg stock was over 6 times higher (4324 g C m-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 suggest that the Finnish eelgrass meadows are minor carbon sinks compared to the Danish meadows, and that majority of the Corg produced in the Finnish meadows is exported. Our analysis further showed that > 40 % of the variation in the Corg stocks was explained by sediment characteristics, i.e. dry density, porosity and silt content. In addition, our analysis show that the root : shoot ratio of Z. marina explained > 12 % and the contribution of Z. marina detritus to the sediment surface Corg pool explained > 10 % of the variation in the Corg stocks. The mean monetary value for the present carbon storage and carbon sink capacity of eelgrass meadows in Finland and Denmark, were 281 and 1809 EUR ha-1, respectively. For a more comprehensive picture of seagrass carbon storage capacity, we conclude that future blue carbon studies should, in a more integrative way, investigate the interactions between sediment biogeochemistry, seascape structure, plant species architecture and the hydrodynamic regime.

  11. Seagrass meadows as a globally significant carbonate reservoir

    KAUST Repository

    Mazarrasa, I.

    2015-03-06

    There has been a 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 organic carbon (POC) stocks and accumulation rates and ignored the 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 402 vegetated and 34 adjacent un-vegetated sites. PIC stocks in the top 1 m sediments ranged between 3 and 1660 Mg PIC ha-1, with an average of 654 ± 24 Mg PIC ha-1, exceeding about 5 fold those of POC reported in previous studies. 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 degree-1 of latitude (GLM, p < 0.0003). Using PIC concentration and estimates of sediment accretion in seagrass meadows, mean PIC accumulation rates in seagrass sediments is 126.3 ± 0.7 g PIC m-2 y-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 meter of sediment and accumulate between 22 and 76 Tg PIC y-1, representing a significant contribution to the carbonate dynamics of coastal areas. Despite that these high rates of carbonate accumulation imply CO2 emissions from precipitation, seagrass meadows are still strong CO2 sinks as demonstrates the comparison of carbon (POC and POC) stocks between vegetated and adjacent un-vegetated sediments.

  12. Biodiversity loss in seagrass meadows due to local invertebrate fisheries and harbour activities

    Science.gov (United States)

    Nordlund, Lina Mtwana; Gullström, Martin

    2013-12-01

    Seagrass meadows provide a wide variety of ecosystem services, but their distribution and health are adversely affected by man. In the present study, we examined the influence of coastal exploitation in terms of invertebrate harvesting and harbour activity on invertebrate community composition in subtropical seagrass meadows at Inhaca Island, Mozambique, in the Western Indian Ocean. There was a fivefold higher invertebrate density and biomass, and clearly higher invertebrate species richness, in the protected (control) site compared to the two exploited sites. The causes for the clear differences between protected and exploited sites were probably a result of (1) the directional outtake of large edible or saleable invertebrates (mostly molluscs) and the absence of boat traffic in the harvested site, and (2) harbour activities. Invertebrate community composition in the two exploited sites also differed (although less clear), which was likely due to inherent distinction in type of disturbance. Our findings revealed that protection of seagrass habitat is necessary and that disturbances of different origin might require different forms of management and conservation. Designing protected areas is however a complex process due to competition for use and space with activities such as invertebrate harvesting and harbours.

  13. 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.

  14. Simulating land-cover change in Montane mainland southeast Asia.

    Science.gov (United States)

    Fox, Jefferson; Vogler, John B; Sen, Omer L; Giambelluca, Thomas W; Ziegler, Alan D

    2012-05-01

    We used the conversion of land use and its effects (CLUE-s) model to simulate scenarios of land-cover change in Montane mainland southeast Asia (MMSEA), a region in the midst of transformation due to rapid intensification of agriculture and expansion of regional trade markets. Simulated changes affected approximately 10 % of the MMSEA landscape between 2001 and 2025 and 16 % between 2001 and 2050. Roughly 9 % of the current vegetation, which consists of native species of trees, shrubs, and grasses, is projected to be replaced by tree plantations, tea, and other evergreen shrubs during the 50 years period. Importantly, 4 % of this transition is expected to be due to the expansion of rubber (Hevea brasiliensis), a tree plantation crop that may have important implications for local-to-regional scale hydrology because of its potentially high water consumption in the dry season.

  15. 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.

  16. [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.

  17. Seagrass meadows as a globally significant carbonate reservoir

    OpenAIRE

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

    2015-01-01

    There has been a 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 organic carbon (POC) stocks and accumulation rates and ignored the inorganic carbon (PIC) fraction, despite important carbonate pools associated with calcifying organisms inhabiting the meadows, such as epiphytes and benthic invertebrates, and...

  18. Seagrass meadows as a globally significant carbonate reservoir

    OpenAIRE

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

  19. Seagrass meadows as a globally significant carbonate reservoir

    Directory of Open Access Journals (Sweden)

    I. Mazarrasa

    2015-03-01

    Full Text Available There has been a 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 organic carbon (POC stocks and accumulation rates and ignored the 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 402 vegetated and 34 adjacent un-vegetated sites. PIC stocks in the top 1 m sediments ranged between 3 and 1660 Mg PIC ha-1, with an average of 654 ± 24 Mg PIC ha-1, exceeding about 5 fold those of POC reported in previous studies. 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 degree-1 of latitude (GLM, p -2 y-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 meter of sediment and accumulate between 22 and 76 Tg PIC y-1, representing a significant contribution to the carbonate dynamics of coastal areas. Despite that these high rates of carbonate accumulation imply CO2 emissions from precipitation, seagrass meadows are still strong CO2 sinks as demonstrates the comparison of carbon (POC and POC stocks between vegetated and adjacent un-vegetated sediments.

  20. 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

  1. Microbial carbon mineralization in tropical lowland and montane forest soils of Peru

    Directory of Open Access Journals (Sweden)

    Jeanette eWhitaker

    2014-12-01

    Full Text Available Climate change is affecting the amount and complexity of plant inputs to tropical forest soils. This is likely to influence the carbon (C balance of these ecosystems by altering decomposition processes e.g. ‘positive priming effects’ that accelerate soil organic matter mineralization. However, the mechanisms determining the magnitude of priming effects are poorly understood. We investigated potential mechanisms by adding 13C labelled substrates, as surrogates of plant inputs, to soils from an elevation gradient of tropical lowland and montane forests. We hypothesised that priming effects would increase with elevation due to increasing microbial nitrogen limitation, and that microbial community composition would strongly influence the magnitude of priming effects. Quantifying the sources of respired C (substrate or soil organic matter in response to substrate addition revealed no consistent patterns in priming effects with elevation. Instead we found that substrate quality (complexity and nitrogen content was the dominant factor controlling priming effects. For example a nitrogenous substrate induced a large increase in soil organic matter mineralization whilst a complex C substrate caused negligible change. Differences in the functional capacity of specific microbial groups, rather than microbial community composition per se, were responsible for these substrate-driven differences in priming effects. Our findings suggest that the microbial pathways by which plant inputs and soil organic matter are mineralized are determined primarily by the quality of plant inputs and the functional capacity of microbial taxa, rather than the abiotic properties of the soil. Changes in the complexity and stoichiometry of plant inputs to soil in response to climate change may therefore be important in regulating soil C dynamics in tropical forest soils.

  2. Diversification of tanagers, a species rich bird group, from lowlands to montane regions of South America

    DEFF Research Database (Denmark)

    Fjeldså, Jon; Rahbek, Carsten

    2006-01-01

    The process of diversification since the late Tertiary was studied by linking together well-resolved phylogenies and species distributions for tanagers (Aves, Thraupini). Species richness patterns reveal very high densities of range-restricted species in the Andes, and to a lesser extent in the A......The process of diversification since the late Tertiary was studied by linking together well-resolved phylogenies and species distributions for tanagers (Aves, Thraupini). Species richness patterns reveal very high densities of range-restricted species in the Andes, and to a lesser extent...... be explained well from topography and landscape complexity. Phylogenetically old species are mainly found along the Andes and along the Rio coast of Brazil. Most other areas outside the Andes probably had very moderate rates of later diversification. In contrast, the humid tropical Andes region was a centre...... of intensive speciation throughout the evolutionary history of the group, and species richness patterns here seem largely to be driven by the rate of speciation, with further diversification from the highlands into adjacent lowlands. The diversification process in montane areas may be related to high...

  3. Uranium delivery and uptake in a montane wetland, north-central Colorado, USA

    Science.gov (United States)

    Schumann, R. Randall; Zielinski, Robert A.; Otton, James K.; Pantea, Michael P.; Orem, William H.

    2017-01-01

    Comprehensive sampling of peat, underlying lakebed sediments, and coexisting waters of a naturally uraniferous montane wetland are combined with hydrologic measurements to define the important controls on uranium (U) supply and uptake. The major source of U to the wetland is groundwater flowing through locally fractured and faulted granite gneiss of Proterozoic age. Dissolved U concentrations in four springs and one seep ranged from 20 to 83 ppb (μg/l). Maximum U concentrations are ∼300 ppm (mg/kg) in lakebed sediments and >3000 ppm in peat. Uranium in lakebed sediments is primarily stratabound in the more organic-rich layers, but samples of similar organic content display variable U concentrations. Post-depositional modifications include variable additions of U delivered by groundwater. Uranium distribution in peat is heterogeneous and primarily controlled by proximity to groundwater-fed springs and seeps that act as local point sources of U, and by proximity to groundwater directed along the peat/lakebeds contact. Uranium is initially sorbed on various organic components of peat as oxidized U(VI) present in groundwater. Selective extractions indicate that the majority of sorbed U remains as the oxidized species despite reducing conditions that should favor formation of U(IV). Possible explanations are kinetic hindrances related to strong complex formation between uranyl and humic substances, inhibition of anaerobic bacterial activity by low supply of dissolved iron and sulfate, and by cold temperatures.

  4. Ecohydrological controls over water budgets in floodplain meadows

    Science.gov (United States)

    Morris, Paul J.; Verhoef, Anne; Macdonald, David M. J.; Gardner, Cate M.; Punalekar, Suvarna M.; Tatarenko, Irina; Gowing, David

    2013-04-01

    Floodplain meadows are important ecosystems, characterised by high plant species richness including rare species. Fine-scale partitioning along soil hydrological gradients allows many species to co-exist. Concerns exist that even modest changes to soil hydrological regime as a result of changes in management or climate may endanger floodplain meadows communities. As such, understanding the interaction between biological and physical controls over floodplain meadow water budgets is important to understanding their likely vulnerability or resilience. Floodplain meadow plant communities are highly heterogeneous, leading to patchy landscapes with distinct vegetation. However, it is unclear whether this patchiness in plant distribution is likely to translate into heterogeneous soil-vegetation-atmosphere transfer (SVAT) rates of water and heat, or whether floodplain meadows can reasonably be treated as internally homogeneous in physical terms despite this patchy vegetation. We used a SVAT model, the Soil-Water-Atmosphere-Plants (SWAP) model by J.C. van Dam and co-workers, to explore the controls over the partitioning of water budgets in floodplain meadows. We conducted our research at Yarnton Mead on the River Thames in Oxfordshire, one of the UK's best remaining examples of a floodplain meadow, and which is still managed and farmed in a low-intensity mixed-use manner. We used soil and plant data from our site to parameterise SWAP; we drove the model using in-situ half-hourly meteorological data. We analysed the model's sensitivity to a range of soil and plant parameters - informed by our measurements - in order to assess the effects of different plant communities on SVAT fluxes. We used a novel method to simulate water-table dynamics at the site; the simulated water tables provide a lower boundary condition for SWAP's hydrological submodel. We adjusted the water-table model's parameters so as to represent areas of the mead with contrasting topography, and so different

  5. Temperature sensitivity of soil carbon dioxide and nitrous oxide emissions in mountain forest and meadow ecosystems in China

    Science.gov (United States)

    Zhang, Junjun; Peng, Changhui; Zhu, Qiuan; Xue, Wei; Shen, Yan; Yang, Yanzheng; Shi, Guohua; Shi, Shengwei; Wang, Meng

    2016-10-01

    An incubation experiment was conducted at three temperature levels (8, 18 and 28 °C) to quantify the response of soil CO2 and N2O emissions to temperature in three ecosystems (pine forest, oak forest, and meadow) located in the Qinling Mountains of China, which are considered to be susceptible to disturbance and climate changes, especially global warming. The soil CO2 emission rates increased with temperature and decreased with soil depth; they were the highest in the oak forest (broadleaf forest) and were lower in the pine forest (coniferous forest) and the meadow ecosystem. However, there was no significant difference in the soil N2O emission rates among the three ecosystems. The temperature sensitivity of CO2 and N2O was higher in the forest than in the meadow ecosystem. The Q10 values (temperature sensitivity coefficient) for CO2 and N2O were 1.07-2.25 and 0.82-1.22, respectively, for the three ecosystems. There was also evidence that the CO2 and N2O emission rates were positively correlated. The soil characteristics exhibited different effects on CO2 and N2O emissions among different ecosystems at the three temperature levels. Moreover, the soil dissolved organic carbon (DOC), specific ultraviolet absorbance (SUVA) and nitrate (NO3-) were important factors for CO2 emissions, whereas the soil ammonium (NH4+) and pH were the major controllers of N2O emissions. Unexpectedly, our results indicated that CO2 emissions are more sensitive to increasing temperature than N2O, noting the different feedback of CO2 and N2O emissions to global warming in this region. The different responses of greenhouse gas emissions in different forest types and a meadow ecosystem suggest that it is critical to conduct a comprehensive investigation of the complex mountain forest and meadow ecosystem in the transitional climate zone under global warming. Our research results provide new insight and advanced understanding of the variations in major greenhouse gas emissions (CO2 and N2O

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

    Directory of Open Access Journals (Sweden)

    G. PERGENT

    2014-07-01

    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

  7. Nevada Department of Wildlife Native Fish and Amphibians Field Trip Report: To estimate the population sizes of Ash Meadows Amargosa pupfish and Ash Meadows speckled dace and also to monitor exotic removal efforts.

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Fish population monitoring has been ongoing since the 1980s at Ash Meadows National Wildlife Refuge. This year we conducted surveys on the Ash Meadows Amargosa...

  8. Nevada Department of Wildlife Native Fish and Amphibians Field Trip Report: To estimate the population sizes of Ash Meadows Amargosa pupfish and Ash Meadows speckled dace and also to monitor exotic species removal efforts

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Fish population monitoring has been ongoing since the 1980s at Ash Meadows National Wildlife Refuge. This year we conducted surveys on the Ash Meadows Amargosa...

  9. 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...

  10. Groundwater Surface Trends at Van Norden Meadow, California, from Ground Penetrating Radar Profiles

    Science.gov (United States)

    Tadrick, N. I.; Blacic, T. M.; Yarnell, S. M.

    2014-12-01

    Van Norden meadow in the Donner Summit area west of Lake Tahoe is one of the largest sub-alpine meadows in the Sierra Nevada mountain range. As natural water retention basins, meadows attenuate floods, improve water quality and support vegetation that stabilizes stream banks and promotes high biodiversity. Like most meadows in the Sierras however, over-grazing, road-building, and development has resulted in localized stream incision, degradation, and partial conversion from wet to dry conditions in Van Norden. Additionally, a small dam at the base of the meadow has partially flooded the lower meadow creating reservoir conditions. Privately owned since the late 1800s, Van Norden was recently purchased by a local land trust to prevent further development and return the area to public ownership. Restoration of the natural meadow conditions will involve notching the dam in 2016 to reduce currently impounded water volumes from 250 to less than 50 acre-feet. To monitor the effects of notching the dam on the upstream meadow conditions, better understanding of the surface and groundwater hydrology both pre- and post-restoration is required. We surveyed the meadow in summer 2014 with ground penetrating radar (GPR) to map the groundwater surface prior to restoration activities using a 270MHz antenna to obtain a suite of longitudinal and transverse transects. Groundwater level within the meadow was assessed using both piezometer readings and sweeps of the GPR antenna. Seventeen piezometers were added this year to the 13 already in place to monitor temporal changes in the groundwater surface, while the GPR profiles provided information about lateral variations. Our results provide an estimate of the groundwater depth variations across the upper portion of the meadow before notching. We plan to return in 2015 to collect GPR profiles during wetter conditions, which will provide a more complete assessment of the pre-notching groundwater hydrology.

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

    Science.gov (United States)

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

    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. Our objective was to describe patterns and variability in aboveground live vascular plant biomass in relation to climatic factors. We harvested aboveground biomass at peak growth from four 64-m2 plots each in xeric, mesic, and hydric meadows annually from 1994 to 2000. Data from nearby weather stations provided independent variables of spring snow water content, snow-free date, and thawing degree days for a cumulative index of available energy. We assembled these climatic variables into a set of mixed effects analysis of covariance models to evaluate their relationships with annual aboveground net primary productivity (ANPP), and we used an information theoretic approach to compare the quality of fit among candidate models. ANPP in the xeric meadow was negatively related to snow water content and thawing degree days and in the mesic meadow was negatively related to snow water content. Relationships between ANPP and these 2 covariates in the hydric meadow were not significant. Increasing snow water content may limit ANPP in these meadows if anaerobic conditions delay microbial activity and nutrient availability. Increased thawing degree days may limit ANPP in xeric meadows by prematurely depleting soil moisture. Large within-year variation of ANPP in the hydric meadow limited sensitivity to the climatic variables. These relationships suggest that, under projected warmer and drier conditions, ANPP will increase in mesic meadows but remain unchanged in xeric meadows because declines associated with increased temperatures would offset the increases from decreased snow water content.

  12. Cattle grazing and conservation of a meadow-dependent amphibian species in the Sierra Nevada.

    Directory of Open Access Journals (Sweden)

    Leslie M Roche

    Full Text Available World-wide population declines have sharpened concern for amphibian conservation on working landscapes. Across the Sierra Nevada's national forest lands, where almost half of native amphibian species are considered at risk, permitted livestock grazing is a notably controversial agricultural activity. Cattle (Bos taurus grazing is thought to degrade the quality, and thus reduce occupancy, of meadow breeding habitat for amphibian species of concern such as the endemic Yosemite toad (Anaxyrus [ = Bufo] canorus. However, there is currently little quantitative information correlating cattle grazing intensity, meadow breeding habitat quality, and toad use of meadow habitat. We surveyed biotic and abiotic factors influencing cattle utilization and toad occupancy across 24 Sierra Nevada meadows to establish these correlations and inform conservation planning efforts. We utilized both traditional regression models and Bayesian structural equation modeling to investigate potential drivers of meadow habitat use by cattle and Yosemite toads. Cattle use was negatively related to meadow wetness, while toad occupancy was positively related. In mid and late season (mid July-mid September grazing periods, cattle selected for higher forage quality diets associated with vegetation in relatively drier meadows, whereas toads were more prevalent in wetter meadows. Because cattle and toads largely occupied divergent zones along the moisture gradient, the potential for indirect or direct negative effects is likely minimized via a partitioning of the meadow habitat. During the early season, when habitat use overlap was highest, overall low grazing levels resulted in no detectable impacts on toad occupancy. Bayesian structural equation analyses supported the hypothesis that meadow hydrology influenced toad meadow occupancy, while cattle grazing intensity did not. These findings suggest cattle production and amphibian conservation can be compatible goals within this

  13. Genetic structure of colline and montane populations of an endangered plant species.

    Science.gov (United States)

    Maurice, Tiphaine; Matthies, Diethart; Muller, Serge; Colling, Guy

    2016-08-12

    Due to land-use intensification, lowland and colline populations of many plants of nutrient-poor grasslands have been strongly fragmented in the last decades, with potentially negative consequences for their genetic diversity and persistence. Populations in mountains might represent a genetic reservoir for grassland plants, because they have been less affected by land-use changes. We studied the genetic structure and diversity of colline and montane Vosges populations of the threatened perennial plant Arnica montana in western central Europe using AFLP markers. Our results indicate that in contrast to our expectation even strongly fragmented colline populations of A. montana have conserved a considerable amount of genetic diversity. However, mean seed mass increased with the proportion of polymorphic loci, suggesting inbreeding effects in low diversity populations. At a similar small geographical scale there was a clear IBD pattern for the montane Vosges but not for the colline populations. However, there was a strong IBD-pattern for the colline populations at a large geographical scale suggesting that this pattern is a legacy of historical gene flow, as most of the colline populations are today strongly isolated from each other. Genetic differentiation between colline and montane Vosges populations was strong. Moreover, results of a genome scan study indicated differences in loci under selection, suggesting that plants from montane Vosges populations might be maladapted to conditions at colline sites. Our results suggest caution in using material from montane populations of rare plants for the reinforcement of small genetically depauperate lowland populations.

  14. Genetic structure of colline and montane populations of an endangered plant species

    Science.gov (United States)

    Maurice, Tiphaine; Matthies, Diethart; Muller, Serge; Colling, Guy

    2016-01-01

    Due to land-use intensification, lowland and colline populations of many plants of nutrient-poor grasslands have been strongly fragmented in the last decades, with potentially negative consequences for their genetic diversity and persistence. Populations in mountains might represent a genetic reservoir for grassland plants, because they have been less affected by land-use changes. We studied the genetic structure and diversity of colline and montane Vosges populations of the threatened perennial plant Arnica montana in western central Europe using AFLP markers. Our results indicate that in contrast to our expectation even strongly fragmented colline populations of A. montana have conserved a considerable amount of genetic diversity. However, mean seed mass increased with the proportion of polymorphic loci, suggesting inbreeding effects in low diversity populations. At a similar small geographical scale, there was a clear IBD pattern for the montane Vosges but not for the colline populations. However, there was a strong IBD-pattern for the colline populations at a large geographical scale suggesting that this pattern is a legacy of historical gene flow, as most of the colline populations are today strongly isolated from each other. Genetic differentiation between colline and montane Vosges populations was strong. Moreover, results of a genome scan study indicated differences in loci under selection, suggesting that plants from montane Vosges populations might be maladapted to conditions at colline sites. Our results suggest caution in using material from montane populations of rare plants for the reinforcement of small genetically depauperate lowland populations. PMID:27519913

  15. Nitrate Removal Along a Colorado Montane Headwater Stream: the Role of Bidirectional Hydrologic Exchange at Reach to Catchment Scales

    Science.gov (United States)

    Smull, E. M.; Gooseff, M. N.

    2015-12-01

    Bidirectional hydrologic exchanges between streams and aquifers can influence nutrient concentrations (physical influx/efflux via gaining/losing water), and/or can facilitate biogeochemical cycling (physical and biological processes). Such exchanges therefore act to influence nutrient fate and transport, and have not yet been captured and incorporated into our understanding of stream nutrient retention and export. Along Colorado's Front Range, research in alpine and subalpine catchments has documented consistent increases in nitrate export, likely due to increased nitrogen deposition from industrialization and fertilization in eastern Colorado. The state of montane zone catchments with respect to their ability to cycle nitrate is not as well understood, however, and such ecosystems have complex hydrologic regimes relative to alpine areas. We applied a fully informed hydrologic mass balance model and nitrate mass balance model that include gross gains and gross losses (bidirectional exchanges) along a 1000 m study reach, to better understand physical and biological nitrate removal for a Colorado montane zone catchment, Lower Gordon Gulch. We collected data during five synoptic stream tracer and sampling campaigns along our study reach during the 2014-2015 water year, and installed wells along the north-facing and south-facing riparian corridor to capture changing water tables. Four distinct hydrologic regimes are captured in our results, including two experiments during baseflow, one experiment following snowmelt, one experiment following late-spring rainfall, and one experiment during the start of the seasonal hydrograph recession in mid-summer. Results show a transition from hydrologic sources of nitrate following snowmelt, to biological sources during rainfall, to biological removal during summer, and finally to hydrologic removal during baseflow. Our findings also corroborate earlier work in montane zone streams that shows preferential flow on south

  16. Chimpanzee seed dispersal in a montane forest fragment in Rwanda.

    Science.gov (United States)

    Chancellor, Rebecca L; Rundus, Aaron S; Nyandwi, Sylvain

    2017-03-01

    Primate seed dispersal plays an important role in forest regeneration. It may be particularly important to anthropogenically disturbed habitats such as forest fragments. However, few studies have examined primate seed dispersal in these types of environments. Chimpanzees (Pan troglodytes) are frugivorous and large-bodied, and are therefore able to disperse both large and small seeds, making them an important seed dispersal species. We examined chimpanzee seed dispersal in Gishwati forest, a 14 km(2) montane rainforest fragment in Rwanda. We systematically collected ≤24-hr-old fecal samples and counted the number of seeds of each fruit species. We also recorded observations of seeds found in wadges. We found that chimpanzees dispersed at least 18 fruit species in 14 families in their feces. Ninety-five percent of feces had seeds, the most common of which were Ficus spp., Myrianthus holstii, and Maesa lanceolata. We estimated that the Gishwati chimpanzee community with a density of 1.7 individuals per km(2) dispersed an average of 592 (>2 mm) seeds km(-2)  day(-1) . We also found that chimpanzees dispersed the seeds of at least two fruit species, Ficus spp. and Chrysophyllum gorungosanum, in their wadges. In addition, 17% of the tree species recorded in our vegetation plots were chimpanzee-dispersed. This study emphasizes the importance of chimpanzees as large seed dispersers in regenerating forest fragments.

  17. Effects of tropical montane forest disturbance on epiphytic macrolichens.

    Science.gov (United States)

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

    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. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Relative abundance and distribution of fishes and crayfish at Ash Meadows National Wildlife Refuge, Nye County, Nevada, 2007-08

    Science.gov (United States)

    Scoppettone, G. Gary; Rissler, Peter; Johnson, Danielle; Hereford, Mark

    2011-01-01

    This study provides baseline data of native and non-native fish populations in Ash Meadows National Wildlife Refuge (NWR), Nye County, Nevada, that can serve as a gauge in native fish enhancement efforts. In support of Carson Slough restoration, comprehensive surveys of Ash Meadows NWR fishes were conducted seasonally from fall 2007 through summer 2008. A total of 853 sampling stations were created using Geographic Information Systems and National Agricultural Imagery Program. In four seasons of sampling, Amargosa pupfish (genus Cyprinodon) was captured at 388 of 659 stations. The number of captured Amargosa pupfish ranged from 5,815 (winter 2008) to 8,346 (summer 2008). The greatest success in capturing Amargosa pupfish was in warm water spring-pools with temperature greater than 25 degrees C, headwaters of warm water spring systems, and shallow (depths less than 10 centimeters) grassy marshes. In four seasons of sampling, Ash Meadows speckled dace (Rhinichthys osculus nevadesis) was captured at 96 of 659 stations. The number of captured Ash Meadows speckled dace ranged from 1,009 (summer 2008) to 1,552 (winter 2008). The greatest success in capturing Ash Meadows speckled dace was in cool water spring-pools with temperature less than 20 degrees C and in the high flowing water outflows. Among 659 sampling stations within the range of Amargosa pupfish, red swamp crayfish (Procambarus clarkii) was collected at 458 stations, western mosquitofish (Gambusia affinis) at 374 stations, and sailfin molly (Poecilia latipinna) at 128 stations. School Springs was restored during the course of this study. Prior to restoration of School Springs, maximum Warm Springs Amargosa pupfish (Cyprinodon nevadensis pectoralis) captured from the six springs of the Warm Springs Complex was 765 (fall 2007). In four seasons of sampling, Warm Springs Amargosa pupfish were captured at 85 of 177 stations. The greatest success in capturing Warm Springs Amargosa pupfish when co-occurring with red

  19. Scientific Opinion on the re-evaluation of montan acid esters (E 912 as a food additive

    Directory of Open Access Journals (Sweden)

    EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS

    2013-06-01

    Full Text Available Following a request from the European Commission, the EFSA Panel on Food Additives and Nutrient Sources added to Food (ANS was asked to deliver a scientific opinion re-evaluating the safety of montan acid esters (E 912 when used as a food additive. Montan acids are extracted from oxidised montan wax and esterified with ethylene glycol, 1,3-butanediol or triols, to form montan acid esters. Montan acid esters are authorised only for the surface treatment of fresh fruits. No data, specifically for montan acid esters, on toxicokinetics and reproductive and developmental toxicity were available. The available data on short-term and subchronic toxicity, genotoxicity and chronic toxicity and carcinogenicity were limited. Important deficiencies in the available studies on chronic toxicity and carcinogenicity were noticed. The data requested in the 1990s (i.e. chromosomal aberration in vitro, reproduction and teratogenicity studies, material characteristics, impurities, presence of PAHs were not submitted. Furthermore no data were submitted following an EFSA public call for data in 2012. The Panel identified some summary data in the European Chemicals Agency database (ECHA on registered substances that might have been relevant for the assessment of montan acid esters but the original study reports were not made available to EFSA. Based on these limitations in the toxicological database the Panel concluded that montan acid esters as a food additive could not be evaluated.

  20. 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.

  1. 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...... density, porosity and silt content. In addition, our analysis show that the root : shoot ratio of Z. marina explained >12% and the contribution of Z. marina detritus to the sediment surface C-org pool explained >10% of the variation in the C-org stocks. The mean monetary value for the present carbon...

  2. Sustainable Management of Seagrass Meadows: the GEOSS AIP-6 Pilot

    Science.gov (United States)

    Santoro, Mattia; Pastres, Roberto; Zucchetta, Matteo; Venier, Chiara; Roncella, Roberto; Bigagli, Lorenzo; Mangin, Antoine; Amine Taji, Mohamed; Gonzalo Malvarez, Gonzalo; Nativi, Stefano

    2014-05-01

    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. To estimate seagrass meadows distribution, a Species Distribution Model (SDM) can be used. SDM is a tool that is used to evaluate the potential distribution of a given species (e.g. Posidonia oceanica for seagrass) on the basis of the features (bio-chemical-physical parameters) of the studied environment. In the framework of the GEOSS (Global Earth Observation System of Systems) initiative, the FP7 project MEDINA developed a showcase as part of the GEOSS Architecture Interoperability Pilot - phase 6 (AIP-6). The showcase aims at providing a tool for the sustainable management of seagrass meadows along the Mediterranean coastline by integrating the SDM with available GEOSS resources. This way, the required input data can be searched, accessed and ingested into the model leveraging the brokering framework of the GEOSS Common Infrastructure (GCI). This framework is comprised of a set of middle-ware components (Brokers) that are in charge of implementing the needed interoperability

  3. 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.

  4. Restoration of wooded meadows - a comparative analysis along a chronosequence on Oland (Sweden)

    NARCIS (Netherlands)

    Mitlacher, K; Poschlod, P; Rosen, E; Bakker, JP

    2002-01-01

    Wooded meadows on the Baltic Island of Oland result from traditional agricultural management over centuries, which has led to a species-rich vegetation with high species diversity. Today. nearly all of these meadows have been abandoned and became rapidly overgrown by deciduous shrub and tree species

  5. Ten Years of Change in Sierran Stringer Meadows: An Evaluation of Range Condition Models

    Science.gov (United States)

    Barbara H. Allen

    1989-01-01

    Grazed Sierra Nevada stringer meadow systems were sampled on Blodgett Forest Research Station in northern California between 1977 and 1987 to determine cattle use, and to examine changes in production and species composition over time. Utilization of meadow species averaged 61 percent over the 10 years, but use increased to more than 80 percent utilization after 1985....

  6. Experiments on the restoration of species-rich meadows in The Netherlands

    NARCIS (Netherlands)

    Berendse, F.; Oomes, M.J.M.; Altena, H.J.; Elberse, W.Th.

    1992-01-01

    Three long-term experiments were carried out in meadows that were mown twice a year on three different soils: heavy clay, sand and clay-on-peat. The experiment on heavy clay studied the effect of an increase in nutrient supply on dry matter production and species diversity in a species-rich meadow.

  7. 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.

  8. DISTRIBUTION AND QUALITY OF SEAGRASS MEADOWS IN THE PENSACOLA BAY SYSTEM

    Science.gov (United States)

    Abstract for oral presentation: Seagrass meadows have 22 ecological benefits and have an estimated value of $20,500 per acre in Florida. Seagrass meadows support a variety of marine life that includes macroalgae (148 species), epiphytes (1 13 species), macroinvertebrates (230 spe...

  9. Comparative Study Of Alluvial Cnidion-Type Meadows In The Lower Danube River Basin

    Directory of Open Access Journals (Sweden)

    Schneider-Binder Erika

    2014-10-01

    Full Text Available Alluvial Cnidion-type meadows (Habitat type 6440 of the Habitats Directive, mostly characteristic for the lower courses of large rivers in continental climate conditions of Europe are presented from the Lower Danube upstream the municipality of Giurgiu (river-km 510-524. The ecological requirements of the characteristic species, as well as their sensitivity to human-induced changes that derive from regular flooding, drainage, intensification of use and/or abandonment, are highlighted; these changes frequently lead to a decrease of biodiversity of the Cnidion-type meadows or to their total loss The studied meadows are compared with similar alluvial meadows from other sites of the lower Danube River basin. Finally, the strong interlocking of Cnidion type meadows with those of the Agropyro-Rumicion, Molinion and Deschampsion caespitosae alliances are discussed.

  10. Mitochondrial phylogeny shows multiple independent ecological transitions and northern dispersion despite of Pleistocene glaciations in meadow and steppe vipers (Vipera ursinii and Vipera renardi).

    Science.gov (United States)

    Zinenko, Oleksandr; Stümpel, Nikolaus; Mazanaeva, Lyudmila; Bakiev, Andrey; Shiryaev, Konstantin; Pavlov, Aleksey; Kotenko, Tatiana; Kukushkin, Oleg; Chikin, Yury; Duisebayeva, Tatiana; Nilson, Göran; Orlov, Nikolai L; Tuniyev, Sako; Ananjeva, Natalia B; Murphy, Robert W; Joger, Ulrich

    2015-03-01

    The phylogeny and historical demography of small Eurasian vipers of the Vipera ursinii and V. renardi complexes were studied using mitochondrial DNA sequences analysed with Bayesian inference, Maximum Likelihood and Maximum Parsimony approaches, and mismatch distributions. Diversification in the group resulted from an initial dispersion in the later Pliocene - Pleistocene in two directions: north-westwards via the Balkans (V. ursinii complex) and north-eastwards from Asia Minor via the Caucasus (V. renardi complex). An independent, comparatively recent transition occurred from montane habitats to lowland grasslands in different mitochondrial lineages during the Late Pleistocene, when representatives of the both complexes had reached lowland steppes to the north. Effective population size showed clear signs of rapid growth in eastern V. renardi, triggered by colonization of vast lowland steppes, but in western V. ursinii complex grew during the Last Glaciation and experienced stabilization in Holocene. Expansion and population growth in lowland lineages of V. renardi was not strongly affected by Pleistocene climatic oscillations, when cold, dry conditions could have favoured species living in open grasslands. The high diversity of closely related haplotypes in the Caucasus and Tien-Shan could have resulted from repetitive expansion-constriction-isolation events in montane regions during Pleistocene climate fluctuations. The mitochondrial phylogeny pattern conflicts with the current taxonomy. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Macroscopic Thermal Energy Balance on Montane Valley Aquifers and Groundwater Recharge Source Identification

    Science.gov (United States)

    Trask, J. C.; Fogg, G. E.

    2010-12-01

    Several recent publications have highlighted the need to improve definition of groundwater flow patterns in montane regions, presenting case studies with several field investigative approaches. Determination of the depth of upland bedrock groundwater circulation and identification of valley aquifer recharge sources in montane areas is needed for improved characterization of montane groundwater flow patterns and for aquifer source protection planning. In most upland bedrock regions, wells and boreholes are scarce, adding to the challenges inherent to investigating groundwater flow in fractured rock systems. Approaches using natural environmental tracers have previously been shown to be effective in quantifying subsurface recharge into valley aquifers from groundwater flow within adjoining mountain-front and mountain-block areas. Thermal tracing of montane groundwater flow is easy and inexpensive relative to other environmental tracer and geophysical techniques, and can complement other approaches (e.g. Manning and Solomon, 2005). We present a heat flow tracer approach to identification of montane valley aquifer recharge sources. A novel application of a macroscopic thermal energy balance is introduced and used in recharge source analysis for two mountain-front bounding basin-fill aquifers located in the Sierra Nevada, USA. We show that robust upper and lower bounds on total heat flow and sources of recharge into montane valley aquifers may be determined without numerical modeling by using a macroscopic thermal energy balance. Several factors tend to enhance focusing of geothermal conductive heat flow from depth toward montane valley margins. Analytic bracketing techniques, applicable to domains with irregular boundary geometry and non-uniform thermal boundary conditions, are used together with thermal data to obtain quantitative bounds on conductive heat flow across aquifer domain boundaries. Thermal data required include: (i) a rough estimate of regional geothermal

  12. 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

  13. 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

  14. Factors influencing stream baseflow transit times in tropical montane watersheds

    Science.gov (United States)

    Muñoz-Villers, Lyssette E.; Geissert, Daniel R.; Holwerda, Friso; McDonnell, Jeffrey J.

    2016-04-01

    Stream water mean transit time (MTT) is a fundamental hydrologic parameter that integrates the distribution of sources, flow paths, and storages present in catchments. However, in the tropics little MTT work has been carried out, despite its usefulness for providing important information on watershed functioning at different spatial scales in (largely) ungauged basins. In particular, very few studies have quantified stream MTTs or have related these to catchment characteristics in tropical montane regions. Here we examined topographic, land use/cover and soil hydraulic controls on baseflow transit times for nested catchments (0.1-34 km2) within a humid mountainous region, underlain by volcanic soil (Andisols) in central Veracruz (eastern Mexico). We used a 2-year record of bi-weekly isotopic composition of precipitation and stream baseflow data to estimate MTT. Land use/cover and topographic parameters (catchment area and form, drainage density, slope gradient and length) were derived from geographic information system (GIS) analysis. Soil water retention characteristics, and depth and permeability of the soil-bedrock interface were obtained from intensive field measurements and laboratory analysis. Results showed that baseflow MTTs ranged between 1.2 and 2.7 years across the 12 study catchments. Overall, MTTs across scales were mainly controlled by catchment slope and the permeability observed at the soil-bedrock interface. In association with topography, catchment form and the depth to the soil-bedrock interface were also identified as important features influencing baseflow MTTs. The greatest differences in MTTs were found both within groups of small (0.1-1.5 km2) and large (14-34 km2) catchments. Interestingly, the longest stream MTTs were found in the headwater cloud forest catchments.

  15. Ten Years of Rainfall and Community-Based Streamflow Monitoring in the Tropical Montane Cloud Forest Region of Central Veracruz, Mexico: What Do These Data Tell Us?

    Science.gov (United States)

    Holwerda, F.; Aranda-Delgado, E.; Castilleja-Delgado, E.; Munoz-Villers, L.

    2016-12-01

    Montane ecosystems and the water resources provided by them play a crucial role in the development and growth of cities and the productive sector in Mexico. For the planning and sustainable management of these resources, it is necessary to quantify the key hydrological components and have (at least some) basic understanding of the water cycle at the operational watershed-scale. However, the difficulty of implementing and maintaining rainfall-discharge observation networks due to the lack of financial resources and well-trained personnel, coupled with poor accessibility and safety, as well as the complexity of the biophysical and climatic conditions in montane regions have hampered progress in hydrological research and the generation of basic knowledge for the benefit of society. In 2005, research-motivated measurements of rainfall (P) and community-based observations of streamflow (Q) were initiated independently in the tropical montane cloud forest (TMCF) region of central Veracruz, Mexico. In this presentation, we will explore these data to study the seasonal and annual P inputs and Q outputs of the ca. 11,000 ha Pixquiac river watershed as observed during the past ten years (2005-2015). The P data used in this analysis include continuous measurements from the major recharge zone within the study area (2000-2300 m asl), supplemented with observations from lower and higher altitudes to determine the P-elevation relationship. The Q data of the Pixquiac river consist of monthly measurements made near the outlet of the watershed (1300-1400 m asl) by citizen volunteers using the Global Water Watch methodology. We expect that these observations will contribute to an improved understanding of the hydrometeorology of mesoscale TMCF watersheds in central Veracruz, which is a prerequisite for sustainable planning and management of the water resources in this region.

  16. Population structure and secondary production of Siriella clausii, a dominant detritus feeding mysid in Posidonia oceanica meadows (W Mediterranean Sea)

    Science.gov (United States)

    Barberá, Carmen; Sanchez-Jerez, Pablo; Sorbe, Jean Claude

    2013-10-01

    Temporal trends in abundance, demographic structure of the population and secondary production of Siriella clausii were studied at three different sectors of Posidonia oceanica meadows in the SE Iberian Peninsula, with different levels of habitat complexity. Secondary production was calculated through three methods widely employed in marine invertebrates: the Hynes method (based on demographic structure data) and models by Morin-Bourassa and Brey (based on biomass data). This filter/grazer and detritus feeder is the most abundant mysid in P. oceanica seagrass meadows in the Mediterranean. The population structure was similar in the three sectors, but the temporal pattern of abundance was different, at times even opposite. This pattern may be related to the aggregated spatial distribution, metapopulation dynamics or stochastic factors, but other potential factors could be involved, such as habitat features or predation rates. The values of production oscillated between 25 and 60 mgAFDW/m2/year, depending on the calculation method that was applied, and showed differences between sites and seagrass complexity. The present values are intermediate between those characterising highly productive systems, such as estuaries, and systems of limited productivity (bathyal habitats). Compared to other peracarids, mysid production is greater than that of isopods and less than amphipod production. This is possibly related to the life cycle and reproductive strategies. Detritus feeders such as S. clausii may play an important trophic role due their capacity to use as food the biomass associated to detritus, which constitutes larges reservoirs of carbon derived from seagrass primary production.

  17. Comparative study on CO2 emissions from different types of alpine meadows during grass exuberance period

    Institute of Scientific and Technical Information of China (English)

    HUQiwu; CAOGuangmin; WUQin; LIDong; WANGYuesi

    2004-01-01

    Potentilla fruticosa scrub, Kobresia humilis meadow and Kobresia tibetica meadow are widely distributed on the Qinghai-Tibet Plateau. During the grass exuberance period from 3 July to 4 September, based on close chamber-GC method, a study on CO2 emissions from different treatments was conducted in these meadows at Haibei research station, CAS. Results indicated that mean CO2 emission rates from various treatments were 672.09±152.37 mgm-2h-1 for FC (grass treatment); 425.41±191.99 mgm-2h-1 for FJ (grass exclusion treatment); 280.36±174.83 mgm-2h-1 for FL (grass and roots exclusion treatment); 838.95±237.02 mgm-2h-1 for GG (scrub+grass treatment); 528.48±205.67 mgm-2h-1 for GC (grass treatment); 268.97±99.72 mgm-2h-1 for GL (grass and roots exclusion treatment); and 659.20±94.83 mgm-2h-1 for LC (grass treatment), respectively (FC, FJ, FL, GG, GC, GL, LC were the Chinese abbreviation for various treatments). Furthermore, Kobresia humilis meadow, Potentilla fruticosa scrub meadow and Kobresia tibetica meadow differed greatly in average CO2 emission rate of soil-plant system, in the order of GG>FC>LC>GC. Moreover, in Kobresia hurnilis meadow,heterotrophic and autotrophic respiration accounted for 42% and 58% of the total respiration of soil-plant system respectively, whereas, in Potentilla fruticosa scrub meadow, heterotrophic and autotrophic respiration accounted for 32% and 68% of total system respiration from GG; 49% and 51% from GC. In addition, root respiration from Kobresia humilis meadow approximated 145 mgCO2m-2h-1,contributed 34% to soil respiration. During the experiment period, Kobresia humilis meadow and Potentilla fruticosa scrub meadow had a net carbon fixation of 111.11 gm-2 and 243.89 gm-2 respectively. Results also showed that soil temperature was the main factor which influenced CO2 emission from alpine meadow ecosystem, significant correlations were found between soil temperature at 5 cm depth and CO2 emission from GG, GC, FC and FJ treatments

  18. 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

  19. 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...

  20. Modification of global precipitation data for enhanced hydrologic modeling of tropical montane watersheds

    Science.gov (United States)

    Strauch, Michael; Kumar, Rohini; Eisner, Stephanie; Mulligan, Mark; Reinhardt, Julia; Samaniego, Luis; Santini, William; Vetter, Tobias; Friesen, Jan

    2016-04-01

    Global gridded precipitation is an essential driving input for hydrologic models to simulate runoff dynamics in large river basins. However, the data often fail to adequately represent precipitation variability in mountainous regions due to orographic effects and sparse and highly uncertain gauge data. Water balance simulations in tropical montane regions covered by cloud forests are especially challenging because of the additional water input from cloud water interception. The ISI-MIP2 hydrologic model ensemble encountered these problems for Andean sub-basins of the Upper Amazon Basin, where all models significantly underestimated observed runoff. In this paper, we propose simple yet plausible ways to adjust global precipitation data provided by WFDEI, the WATCH Forcing Data methodology applied to ERA-Interim reanalysis, for tropical montane watersheds. The modifications were based on plausible reasoning and freely available tropics-wide data: (i) a high-resolution climatology of the Tropical Rainfall Measuring Mission (TRMM) and (ii) the percentage of tropical montane cloud forest cover. Using the modified precipitation data, runoff predictions significantly improved for all hydrologic models considered. The precipitation adjustment methods presented here have the potential to enhance other global precipitation products for hydrologic model applications in the Upper Amazon Basin as well as in other tropical montane watersheds.

  1. 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 zones of the northern subtropics beeches (Fagus engl

  2. 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...

  3. 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.

  4. 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

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

    Science.gov (United States)

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

    2014-09-01

    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 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.

  6. Drivers of atmospheric methane uptake by montane forest soils in the southern Peruvian Andes

    Science.gov (United States)

    Jones, Sam P.; Diem, Torsten; Huaraca Quispe, Lidia P.; Cahuana, Adan J.; Reay, Dave S.; Meir, Patrick; Arn Teh, Yit

    2016-07-01

    The soils of tropical montane forests can act as sources or sinks of atmospheric methane (CH4). Understanding this activity is important in regional atmospheric CH4 budgets given that these ecosystems account for substantial portions of the landscape in mountainous areas like the Andes. We investigated the drivers of net CH4 fluxes from premontane, lower and upper montane forests, experiencing a seasonal climate, in south-eastern Peru. Between February 2011 and June 2013, these soils all functioned as net sinks for atmospheric CH4. Mean (standard error) net CH4 fluxes for the dry and wet season were -1.6 (0.1) and -1.1 (0.1) mg CH4-C m-2 d-1 in the upper montane forest, -1.1 (0.1) and -1.0 (0.1) mg CH4-C m-2 d-1 in the lower montane forest, and -0.2 (0.1) and -0.1 (0.1) mg CH4-C m-2 d-1 in the premontane forest. Seasonality in CH4 exchange varied among forest types with increased dry season CH4 uptake only apparent in the upper montane forest. Variation across these forests was best explained by available nitrate and water-filled pore space indicating that nitrate inhibition of oxidation or diffusional constraints imposed by changes in water-filled pore space on methanotrophic communities may represent important controls on soil-atmosphere CH4 exchange. Net CH4 flux was inversely related to elevation; a pattern that differs to that observed in Ecuador, the only other extant study site of soil-atmosphere CH4 exchange in the tropical Andes. This may result from differences in rainfall patterns between the regions, suggesting that attention should be paid to the role of rainfall and soil moisture dynamics in modulating CH4 uptake by the organic-rich soils typical of high-elevation tropical forests.

  7. [Prognosis of accumulation of 137Cs and 90Sr in the herbage of the main types of the Belarus Polessje meadows using agrochemical soil properties].

    Science.gov (United States)

    Podoliak, A G; Timofeev, S F; Grebenshchikova, N V; Arastovich, T V; Zhdanovich, V P

    2005-01-01

    On the basis of long-term stationary experience it was established that the minimum accumulation quantities for 137Cs and 90Sr in the herbage of the dry, lowland and flood-plain types of the Belarus Polessje meadows contaminated with Chemobyl radionuclides are determined when the optimum of basic agrochemical soil properties is achieved with application of the scientifically reasonable protective measures. For remote prognosis of radionuclide contents in natural and cultural meadow herbage the use of transfer factors (TFa, (Bq/kg)(kBq/m2)) based on the complex agrochemical parameters--agrochemical cultivation soil index (Icd) and basic saturation degree (V, %), which take into account some soil characteristics simultaneously, is a streamlined approach. This paper provides the equations of linear and multiple regressions, which 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, that will allow reducing the volume of forage production (hay, green bulk), which is not adequate to established permissible levels: "Republican allowable levels of the contents of 137Cs and 90Sr in agricultural raw material and forages".

  8. Wet Meadow Plant Associations, Malheur National Wildlife Refuge, Harney County, Oregon

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes vegetation data collected in July 2012 and July 2013 in wet meadow habitats on the Malheur National Wildlife Refuge. It incorporates portions...

  9. Sunkhaze Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1990

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for Sunkhaze Meadows National Wildlife Refuge and Carlton Pond Waterfowl Production Area outlines Refuge accomplishments during the 1990...

  10. Sunkhaze Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1991

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for Sunkhaze Meadows National Wildlife Refuge, Carlton Pond Waterfowl Production Area, Benton Unit, and Unity Unit outlines Refuge...

  11. Sunkhaze Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1989

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for Sunkhaze Meadows National Wildlife Refuge outlines Refuge accomplishments during the 1989 calendar year. The report begins by summarizing...

  12. Species status assessment report New Mexico meadow jumping mouse (Zapus hudsonius luteus)

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The New Mexico meadow jumping mouse (Zapus hudsonius luteus) (jumping mouse) lives in dense riparian herbaceous vegetation along streams from southern Colorado to...

  13. Great Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1988

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during the 1988 calendar year. The report begins with a...

  14. Great Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1992

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during the 1992 calendar year. The report begins with a...

  15. Great Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1991

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during the 1991 calendar year. The report begins with a...

  16. Arapaho National Wildlife Refuge and the Owl Moutain Partnership riparian/meadow management demonstration project

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Arapaho National Wildlife Refuge (Refuge) and the Owl Mountain Partnership (OMP) are implementing a 5-year riparian/meadow management demonstration project. The...

  17. Sediment toxicity of Long Meadow Lake Minnesota Valley National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Long Meadow Lake on the Minnesota Valley National Wildlife Refuge - an important waterfowl production area - serves as a major urban stormwater receptor in the...

  18. Annual narrative report: Calendar year 2000: Supawna Meadows National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Supawna Meadows NWR outlines Refuge accomplishments during the 2000 calendar year. The report begins with a summary of the year's...

  19. Supawna Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1996

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Supawna Meadows NWR outlines Refuge accomplishments during the 1996 calendar year. The report begins with a summary of the year's...

  20. Supawna Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1998

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Supawna Meadows NWR outlines Refuge accomplishments during the 1998 calendar year. The report begins with a summary of the year's...

  1. Annual narrative report: Calendar year 2001: Supawna Meadows National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Supawna Meadows NWR outlines Refuge accomplishments during the 2001 calendar year. The report begins with a summary of the year's...

  2. Supawna Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1995

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Supawna Meadows NWR outlines Refuge accomplishments during the 1995 calendar year. The report begins with a summary of the year's...

  3. Ash Meadows National Wildlife Refuge [Land Status Map: Sheet 4 of 4

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This map was produced by the Division of Realty to depict landownership at Ash Meadows National Wildlife Refuge. It was generated from rectified aerial photography,...

  4. Ash Meadows National Wildlife Refuge [Land Status Map: Sheet 1 of 4

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This map was produced by the Division of Realty to depict landownership at Ash Meadows National Wildlife Refuge. It was generated from rectified aerial photography,...

  5. Ash Meadows National Wildlife Refuge [Land Status Map: Sheet 2 of 4

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This map was produced by the Division of Realty to depict landownership at Ash Meadows National Wildlife Refuge. It was generated from rectified aerial photography,...

  6. Ash Meadows National Wildlife Refuge [Land Status Map: Sheet 3 of 4

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This map was produced by the Division of Realty to depict landownership at Ash Meadows National Wildlife Refuge. It was generated from rectified aerial photography,...

  7. Great Meadows National Wildlife Refuge Monthly Narrative: September-December 1993

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during the months of September through December 1993. The...

  8. Sunkhaze Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1995

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Sunkhaze Meadows NWR, Carlton Pond Waterfowl Production Area, Benton Unit, and Unity Unit outlines Refuge accomplishments during the...

  9. Great Meadows National Wildlife Refuge : Annual Narrrative Report : Calendar Year 1985

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during the 1985 calendar year. The report begins with a...

  10. Sunkhaze Meadows National Wildlife Refuge, Carlton Pond National Wildlife Refuge: Annual narrative report: Fiscal year 2001

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Sunhaze Meadows NWR and Carlton Pond WPA outlines activities and accomplishments during the 2001 fiscal year. The report begins with...

  11. Sunkhaze Meadows National Wildlife Refuge and Carlton Pond Waterfowl Production Area: Comprehensive Conservation Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Comprehensive Conservation Plan (CCP) was written to guide management on Sunkhaze Meadows National Wildlife Refuge and Carlton Pond Waterfowl Production Area...

  12. Bird Nesting Effort in Wet Meadows at Baca National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In the summers of 2013, 2015, and 2016, U.S. Fish & Wildlife Service staff conducted research to determine nesting effort of avian species in the wet meadow...

  13. Great Meadows National Wildlife Refuge : Annual Narrrative Report : Calendar Year 1987

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during the 1987 calendar year. The report begins with a...

  14. Outreach Plan : Crane Meadows National Wildlife Refuge : Special Deer & Turkey Hunting Opportunities

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a plan for special deer and turkey hunting opportunities at Crane Meadows NWR. Goals, strategies, messages, and key dates relevant to this plan are outlined.

  15. The Trail Inventory of Ash Meadows National Wildlife Refuge [Cycle 1

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this report is to create a baseline inventory of all non-motorized trails on Ash Meadows National Wildlife Refuge. Trails in this inventory are...

  16. Great Meadows National Wildlife Refuge : Narrative Report : September to December 1960

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments from September to December 1960. The report begins by summarizing...

  17. Great Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1990

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during the 1990 calendar year. The report begins with a...

  18. Archaeological and paleoenvironmental investigations in the Ash Meadows National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is an archeological and paleoenvironmental study of Ash Meadows NWR. Archaeological and paleoenvironmental studies were conducted by the Quaternary Sciences...

  19. Supawna Meadows National Wildlife Refuge annual narrative report calendar year 1997

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Supawna Meadows National Wildlife Refuge outlines Refuge accomplishments during the 1997 calendar year. The report begins with a...

  20. Assessment of Cokeville Meadows National Wildlife Refuge, Wyoming for creosote contamination of wetlands

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Semi-permeable devices (SPMDs) were deployed in wetlands along a railroad right-of-way at the Cokeville Meadows National Wildlife Refuge, Lincoln County, Wyoming to...

  1. Sunkhaze Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1996

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Sunkhaze Meadows NWR, Carlton Pond Waterfowl Production Area, Benton Unit, and Unity Unit outlines Refuge accomplishments during the...

  2. Contaminant survey of Sunkhaze Stream and Baker Brook: Sunkhaze Meadows National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In 1993 a screening-level contaminant survey of the Sunkhaze Meadows National Wildlife Refuge was conducted by the Maine Field Office of the U.S. Fish and Wildlife...

  3. Great Meadows National Wildlife Refuge : Annual Narrrative Report : Calendar Year 1984

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during the 1984 calendar year. The report begins with a...

  4. Malheur NWR: Initial Survey Instructions for Wet Meadow Landbird Point Count

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We will monitor birds tied to wet meadow habitat in Unit 12. This data will be linked with plant community composition data to gain understanding shifting population...

  5. Great Meadows National Wildlife Refuge : Annual Narrrative Report : Calendar Year 1983

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during the 1983 calendar year. The report begins with a...

  6. 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.

  7. Vegetation Classification, Inventory, and Ecological Integrity Assessment of the Wet Meadow Habitats: Malheur National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The objectives of this biotic inventory contribute greatly to the construction of a solid foundation for wet meadow management on the Refuge and the wildlife that it...

  8. Supawna Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1991

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Supawna Meadows NWR outlines Refuge accomplishments during the 1991 calendar year. The report begins with a summary of the year's...

  9. Sunkhaze Meadows National Wildlife Refuge: Annual narrative report: Calendar year 1992

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Sunkhaze Meadows NWR, Carlton Pond Waterfowl Production Area, Benton Unit, and Unity Unit outlines Refuge accomplishments during the...

  10. An Evaluation of Ecosystem Restoration Options for Cokeville Meadows National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Evaluation of Ecosystem Restoration and Management Options covers the hydrogeomorphic analysis (HGM) for Cokeville Meadows National Wildlife Refuge. This three...

  11. Great Meadows National Wildlife Refuge : Annual Narrrative Report : Calendar Year 1982

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Great Meadows National Wildlife Refuge outlines Refuge accomplishments during the 1982 calendar year. The report begins with a...

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

    OpenAIRE

    Hicks, D.M.; Ouvrard, P.; Baldock, K.C.R.; Baude, M.; Goddard, M. A.; Kunin, W.E.; Mitschunas, N.; Memmott, J; Morse, H; Nikolitsi, M; Osgathorpe, L.M.; Potts, S. G.; Robertson, K. M.; Scott, A.V.; Sinclair, F.

    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 t...

  14. Modelling reference conditions for the upper limit of Posidonia oceanica meadows: a morphodynamic approach

    Science.gov (United States)

    Vacchi, Matteo; Misson, Gloria; Montefalcone, Monica; Archetti, Renata; Nike Bianchi, Carlo; Ferrari, Marco

    2014-05-01

    The upper portion of the meadows of the protected Mediterranean seagrass Posidonia oceanica occurs in the region of the seafloor mostly affected by surf-related effects. Evaluation of its status is part of monitoring programs, but proper conclusions are difficult to draw due to the lack of definite reference conditions. Comparing the position of the meadow upper limit with the beach morphodynamics (i.e. the distinctive type of beach produced by topography and wave climate) provided evidence that the natural landwards extension of meadows can be predicted. Here we present an innovative predictive cartographic approach able to identify the seafloor portion where the meadow upper limit should naturally lies (i.e. its reference conditions). The conceptual framework of this model is based on 3 essential components: i) Definition of the breaking depth geometry: the breaking limit represents the major constrain for the landward meadow development. We modelled the breaking limit (1 year return time) using the software Mike 21 sw. ii) Definition of the morphodynamic domain of the beach using the surf scaling index ɛ; iii) Definition of the P. oceanica upper limit geometry. We coupled detailed aerial photo with thematic bionomic cartography. In GIS environment, we modelled the seafloor extent where the meadow should naturally lies according to the breaking limit position and the morphodynamic domain of the beach. Then, we added the GIS layer with the meadow upper limit geometry. Therefore, the final output shows, on the same map, both the reference condition and the actual location of the upper limit. It make possible to assess the status of the landward extent of a given P. oceanica meadow and quantify any suspected or observed regression caused by anthropic factors. The model was elaborated and validated along the Ligurian coastline (NW Mediteraanean) and was positively tested in other Mediterranean areas.

  15. Habitat use of a multispecific seagrass meadow by green turtles Chelonia mydas at Mayotte Island

    OpenAIRE

    Ballorain, Katia; Ciccione, Stephane; Bourjea, Jerome; Grizel, Henri; Enstipp, Manfred; Georges, Jean-Yves

    2010-01-01

    We investigated the habitat use in green turtles exploiting a 13-ha multispecific seagrass meadow at Mayotte Island, south-western Indian Ocean. A phytoecological survey shows the occurrence of eight seagrass species, dominated by Halodule uninervis and Syringodium isoetifolium, distributed according to four distinct seagrass communities along the depth gradient. Direct underwater censuses show that green turtles occurred all over the meadow. Yet when community relative surface area was taken...

  16. Mangroves as a major source of soil carbon storage in adjacent seagrass meadows

    Science.gov (United States)

    Chen, Guangcheng; Azkab, Muhammad Husni; Chmura, Gail L.; Chen, Shunyang; Sastrosuwondo, Pramudji; Ma, Zhiyuan; Dharmawan, I. Wayan Eka; Yin, Xijie; Chen, Bin

    2017-01-01

    Mangrove forests have the potential to export carbon to adjacent ecosystems but whether mangrove-derived organic carbon (OC) would enhance the soil OC storage in seagrass meadows adjacent to mangroves is unclear. In this study we examine the potential for the contribution of mangrove OC to seagrass soils on the coast of North Sulawesi, Indonesia. We found that seagrass meadows adjacent to mangroves had significantly higher soil OC concentrations, soil OC with lower δ 13C, and lower bulk density than those at the non-mangrove adjacent meadows. Soil OC storage to 30 cm depth ranged from 3.21 to 6.82 kg C m−2, and was also significantly higher at the mangrove adjacent meadows than those non-adjacent meadows. δ13C analyses revealed that mangrove OC contributed 34 to 83% to soil OC at the mangrove adjacent meadows. The δ13C value of seagrass plants was also different between the seagrasses adjacent to mangroves and those which were not, with lower values measured at the seagrasses adjacent to mangroves. Moreover, we found significant spatial variation in both soil OC concentration and storage, with values decreasing toward sea, and the contribution of mangrove-derived carbon also reduced with distance from the forest. PMID:28186151

  17. Soil microclimate monitoring in forested and meadow sites

    Science.gov (United States)

    Freyerova, Katerina; Safanda, Jan

    2016-04-01

    It is well known fact that forest microclimate differs from open area microclimate (Geiger 1965). Less attention is paid to soil temperatures and their long-term monitoring. To evaluate and compare these two environments from the soil microclimate point of view, Institute of Geophysics in Prague monitors soil and air temperatures in Bedřichov in the Jizerské Hory Mountains (Czech Republic). The soil temperatures are measured in three depths (20, 50 and 100 cm) in forest (700 m a. s. l.) and meadow (750 m a. s. l.). Air temperatures are measured at 2m height both in forest and meadow. Nowadays, we have more than three years long time series. The most of studies and experiments described in literature are short-term ones (in order of days or weeks). However, from short-term experiments the seasonal behaviour and trends can be hardly identified and conclusions on soil temperature reaction to climatic extremes such as heat waves, drought or freeze cannot be done with confidence. These drawbacks of the short-term experiments are discussed in literature (eg. Morecroft et al. 1998; Renaud et al. 2011). At the same, with progression of the global warming, the expected increasing frequency of climatic extremes will affect the future form of forest vegetation (Von Arx et al. 2012). The soil and air temperature series, both from the forest and meadow sites, are evaluated and interpreted with respect to long term temperature characteristics and seasonal trends. The emphasis is given on the soil temperature responses to extreme climatic situations. We examine variability between the localities and depths and spatial and temporal changes in this variability. This long-term monitoring allows us to better understand and examine the behaviour of the soil temperature in extreme weather situations. Therefore, we hope to contribute to better prediction of future reactions of this specific environments to the climate change. Literature Geiger, R., 1965. The climate near the ground

  18. 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

  19. Effects of cattle grazing on small mammal communities in the Hulunber meadow steppe.

    Science.gov (United States)

    Cao, Chan; Shuai, Ling-Ying; Xin, Xiao-Ping; Liu, Zhi-Tao; Song, Yan-Ling; Zeng, Zhi-Gao

    2016-01-01

    Small mammals play important roles in many ecosystems, and understanding their response to disturbances such as cattle grazing is fundamental for developing sustainable land use strategies. However, how small mammals respond to cattle grazing remains controversial. A potential cause is that most of previous studies adopt rather simple experimental designs based solely on the presence/absence of grazing, and are thus unable to detect any complex relationships between diversity and grazing intensity. In this study, we conducted manipulated experiments in the Hulunber meadow steppe to survey small mammal community structures under four levels of grazing intensities. We found dramatic changes in species composition in native small mammal communities when grazing intensity reached intermediate levels (0.46 animal unit/ha). As grazing intensity increased, Spermophilus dauricus gradually became the single dominant species. Species richness and diversity of small mammals in ungrazed and lightly grazed (0.23 animal unit/ha) area were much higher than in intermediately and heavily grazed area. We did not detect a humped relationship between small mammal diversity and disturbance levels predicted by the intermediate disturbance hypothesis (IDH). Our study highlighted the necessity of conducting manipulated experiments under multiple grazing intensities.

  20. Impacts of different climate change regimes and extreme climatic events on an alpine meadow community.

    Science.gov (United States)

    Alatalo, Juha M; Jägerbrand, Annika K; Molau, Ulf

    2016-02-18

    Climate variability is expected to increase in future but there exist very few experimental studies that apply different warming regimes on plant communities over several years. We studied an alpine meadow community under three warming regimes over three years. Treatments consisted of (a) a constant level of warming with open-top chambers (ca. 1.9 °C above ambient), (b) yearly stepwise increases in warming (increases of ca. 1.0, 1.9 and 3.5 °C), and (c) pulse warming, a single first-year pulse event of warming (increase of ca. 3.5 °C). Pulse warming and stepwise warming was hypothesised to cause distinct first-year and third-year effects, respectively. We found support for both hypotheses; however, the responses varied among measurement levels (whole community, canopy, bottom layer, and plant functional groups), treatments, and time. Our study revealed complex responses of the alpine plant community to the different experimentally imposed climate warming regimes. Plant cover, height and biomass frequently responded distinctly to the constant level of warming, the stepwise increase in warming and the extreme pulse-warming event. Notably, we found that stepwise warming had an accumulating effect on biomass, the responses to the different warming regimes varied among functional groups, and the short-term perturbations had negative effect on species richness and diversity.

  1. Responses of community-level plant-insect interactions to climate warming in a meadow steppe.

    Science.gov (United States)

    Zhu, Hui; Zou, Xuehui; Wang, Deli; Wan, Shiqiang; Wang, Ling; Guo, Jixun

    2015-12-21

    Climate warming may disrupt trophic interactions, consequently influencing ecosystem functioning. Most studies have concentrated on the temperature-effects on plant-insect interactions at individual and population levels, with a particular emphasis on changes in phenology and distribution. Nevertheless, the available evidence from the community level is limited. A 3-year field manipulative experiment was performed to test potential responses of plant and insect communities, and plant-insect interactions, to elevated temperature in a meadow steppe. Warming increased the biomass of plant community and forbs, and decreased grass biomass, indicating a shift from grass-dominant to grass-forb mixed plant community. Reduced abundance of the insect community under warming, particularly the herbivorous insects, was attributed to lower abundance of Euchorthippus unicolor and a Cicadellidae species resulting from lower food availability and higher defensive herbivory. Lower herbivore abundance caused lower predator species richness because of reduced prey resources and contributed to an overall decrease in insect species richness. Interestingly, warming enhanced the positive relationship between insect and plant species richness, implying that the strength of the plant-insect interactions was altered by warming. Our results suggest that alterations to plant-insect interactions at a community level under climate warming in grasslands may be more important and complex than previously thought.

  2. Responses of community-level plant-insect interactions to climate warming in a meadow steppe

    Science.gov (United States)

    Zhu, Hui; Zou, Xuehui; Wang, Deli; Wan, Shiqiang; Wang, Ling; Guo, Jixun

    2015-01-01

    Climate warming may disrupt trophic interactions, consequently influencing ecosystem functioning. Most studies have concentrated on the temperature-effects on plant-insect interactions at individual and population levels, with a particular emphasis on changes in phenology and distribution. Nevertheless, the available evidence from the community level is limited. A 3-year field manipulative experiment was performed to test potential responses of plant and insect communities, and plant-insect interactions, to elevated temperature in a meadow steppe. Warming increased the biomass of plant community and forbs, and decreased grass biomass, indicating a shift from grass-dominant to grass-forb mixed plant community. Reduced abundance of the insect community under warming, particularly the herbivorous insects, was attributed to lower abundance of Euchorthippus unicolor and a Cicadellidae species resulting from lower food availability and higher defensive herbivory. Lower herbivore abundance caused lower predator species richness because of reduced prey resources and contributed to an overall decrease in insect species richness. Interestingly, warming enhanced the positive relationship between insect and plant species richness, implying that the strength of the plant-insect interactions was altered by warming. Our results suggest that alterations to plant-insect interactions at a community level under climate warming in grasslands may be more important and complex than previously thought. PMID:26686758

  3. A multi-scale evaluation of pack stock effects on subalpine meadow plant communities in the Sierra Nevada

    Science.gov (United States)

    Lee, Steven R.; Berlow, Eric L.; Ostoja, Steven M.; Brooks, Matthew L.; Génin, Alexandre; Matchett, John R.; Hart, Stephen C.

    2017-01-01

    We evaluated the influence of pack stock (i.e., horse and mule) use on meadow plant communities in Sequoia and Yosemite National Parks in the Sierra Nevada of California. Meadows were sampled to account for inherent variability across multiple scales by: 1) controlling for among-meadow variability by using remotely sensed hydro-climatic and geospatial data to pair stock use meadows with similar non-stock (reference) sites, 2) accounting for within-meadow variation in the local hydrology using in-situ soil moisture readings, and 3) incorporating variation in stock use intensity by sampling across the entire available gradient of pack stock use. Increased cover of bare ground was detected only within “dry” meadow areas at the two most heavily used pack stock meadows (maximum animals per night per hectare). There was no difference in plant community composition for any level of soil moisture or pack stock use. Increased local-scale spatial variability in plant community composition (species dispersion) was detected in “wet” meadow areas at the two most heavily used meadows. These results suggest that at the meadow scale, plant communities are generally resistant to the contemporary levels of recreational pack stock use. However, finer-scale within-meadow responses such as increased bare ground or spatial variability in the plant community can be a function of local-scale hydrological conditions. Wilderness managers can improve monitoring of disturbance in Sierra Nevada meadows by adopting multiple plant community indices while simultaneously considering local moisture regimes.

  4. Ninigret National Wildlife Refuge Complex: Annual narrative report: Calendar year 1988

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Ninigret National Wildlife Refuge Complex (including Ninigret NWR, Block Island NWR, Sachuest Point NWR, Salt Meadow NWR, Trustom...

  5. 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

  6. 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

  7. 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.

  8. 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

  9. Soil organic carbon and nitrogen content of density fractions and effect of meadow degradation to soil carbon and nitrogen of fractions in alpine Kobresia meadow

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    This research was conducted on the non-disturbed native alpine Kobresia meadow(YF) and the severely degraded meadow(SDL) of Dari County of Qinghai Province.By a density fractionation approach,each soil sample was divided into two fractions:light fraction(LF) and heavy fraction(HF).The obtained fractions were analyzed for organic carbon(OC) and nitrogen(N) concentrations.The results showed:(1) the OC concentration in HF and LF was 3.84% and 28.63% respectively while the nitrogen concentration in HF and LF was 0.362% and 1.192% respectively in 0-10 cm depth.C:N ratio was 10.6 in HF and 23.8 in LF respectively.(2) As far as the ratio of OC in given fraction to that in gross sample was concerned,dominance of OC in HF was obvious in the whole soil profile.OC in HF increased from 78.95% to 90.33%,while OC in LF decreased from 21.05% to 9.68% with depths.(3) Soil total OC amounted to 47.47 in YF while 17.63 g.kg-1 in SDL,in which the OC content in HF decreased from 37.31 to 16.01 g.kg-1 while OC content in LF decreased from 10.01 to 1.62 g.kg-1.In other words,results of OC and N content show meadow degradation led to the loss of 57% OC in HF and 84% OC in LF from originally native ecosystem on alpine meadow.In addition,meadow degradation led to the loss of 43% N in HF and 79% N in LF from originally native ecosystem on alpine meadow.(4) The main reason for loss of C and N in LF during meadow degradation was not attributed to the decrease of OC and N concentration in LF and LF,but to the decrease in LF dry weight.Loss of N was far lower than loss of C in HF.This may suggest that there is difference in protection mode of C and N in HF.

  10. 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.

  11. 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.

  12. Two pulses of diversification across the Isthmus of Tehuantepec in a montane Mexican bird fauna.

    Science.gov (United States)

    Barber, B R; Klicka, J

    2010-09-07

    Understanding the evolutionary history of the species in a particular region provides insights into how that fauna was formed. Of particular interest to biogeographers is examining the impact a geographical barrier had in generating temporal genetic diversity among codistributed species. We examined the impact a major New World barrier, the Isthmus of Tehuantepec (IT) in southern Mexico, had on a regional bird fauna. Specifically, genetic data from 10 montane-forest bird taxa were analysed using approximate Bayesian computation (ABC) to test the hypothesis of simultaneous intraspecific diversification at the IT. Because effective population size (N(e)) has the greatest impact on coalescent times, thereby affecting tests of divergence among codistributed taxa, we chose priors for both current and ancestral N(e) using empirical estimates of theta. The ABC method detected two discrete diversification events. Subsequent analysis with the number of diversification events constrained to two suggests that four taxa diverged in an older event, with the remaining six diverging more recently. Application of a range of mutation rates from 2.0 to 5.0% Myr(-1) places both events within the Pleistocene or Late Pliocene, suggesting that fluctuations in montane habitat induced by climate cycles and a late Pliocene seaway may have fractured this montane bird fauna. The results presented here suggest this avian fauna responded in a relatively concerted fashion over the last several million years.

  13. Negative relationships between cellular immune response, Mhc class II heterozygosity and secondary sexual trait in the montane water vole.

    Science.gov (United States)

    Charbonnel, Nathalie; Bryja, Josef; Galan, Maxime; Deter, Julie; Tollenaere, Charlotte; Chaval, Yannick; Morand, Serge; Cosson, Jean-François

    2010-05-01

    Heterogeneities in immune responsiveness may affect key epidemiological parameters and the dynamics of pathogens. The roles of immunogenetics in these variations remain poorly explored. We analysed the influence of Major histocompatibility complex (Mhc) genes and epigamic traits on the response to phytohaemagglutinin in males from cyclic populations of the montane water vole (Arvicola scherman). Besides, we tested the relevance of lateral scent glands as honest signals of male quality. Our results did not corroborate neither the hypotheses of genome-wide heterozygosity-fitness correlation nor the Mhc heterozygote advantage. We found a negative relationship between Mhc hetetozygosity and response to phytohaemagglutinin, mediated by a specific Mhc homozygous genotype. Our results therefore support the hypothesis of the Arte-Dqa-05 homozygous genotype being a 'good' Mhc variant in terms of immunogenetic quality. The development of the scent glands seems to be an honest signal for mate choice as it is negatively correlated with helminth load. The 'good gene' hypothesis was not validated as Arte-Dqa-05 homozygous males did not exhibit larger glands. Besides, the negative relationship observed between the size of these glands and the response to phytohaemagglutinin, mainly for Mhc homozygotes, corroborates the immunocompetence handicap hypothesis. The Mhc variants associated with larger glands remain yet to be determined.

  14. Does habitat complexity influence fish recruitment?

    Directory of Open Access Journals (Sweden)

    A. CHEMINÉE

    2014-06-01

    Full Text Available Human activities facilitate coastal habitat transformation and homogenization. The spread of marine invasive species is one example. This in turn may influence fish recruitment and the subsequent replenishment of adult assemblages. We tested habitat complexity effect on fish (Teleostei recruitment by experimentally manipulating meadows of the habitat-forming invasive macroalga Caulerpa taxifolia (Chlorophyta. Among the fourteen fish species recorded during the experiment, only two labrids (Coris julis and Symphodus ocellatus settled in abundance among these meadows. Patterns in the abundance of these juveniles suggested that reduced tri-dimensional meadow complexity may reduce habitat quality and result in altered habitat choices and / or differential mortality of juveniles, therefore reducing fish recruitment and likely the abundance of adults.

  15. 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.

  16. 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.

  17. Wet meadow ecosystems contribute the majority of overwinter soil respiration from snow-scoured alpine tundra

    Science.gov (United States)

    Knowles, John F.; Blanken, Peter D.; Williams, Mark W.

    2016-04-01

    We measured soil respiration across a soil moisture gradient ranging from dry to wet snow-scoured alpine tundra soils throughout three winters and two summers. In the absence of snow accumulation, soil moisture variability was principally determined by the combination of mesotopographical hydrological focusing and shallow subsurface permeability, which resulted in a patchwork of comingled ecosystem types along a single alpine ridge. To constrain the subsequent carbon cycling variability, we compared three measures of effective diffusivity and three methods to calculate gradient method soil respiration from four typical vegetation communities. Overwinter soil respiration was primarily restricted to wet meadow locations, and a conservative estimate of the rate of overwinter soil respiration from snow-scoured wet meadow tundra was 69-90% of the maximum carbon dioxide (CO2) respired by seasonally snow-covered soils within this same catchment. This was attributed to higher overwinter soil temperatures at wet meadow locations relative to fellfield, dry meadow, and moist meadow communities, which supported liquid water and heterotrophic respiration throughout the winter. These results were corroborated by eddy covariance-based measurements that demonstrated an average of 272 g C m-2 overwinter carbon loss during the study period. As a result, we updated a conceptual model of soil respiration versus snow cover to express the potential for soil respiration variability from snow-scoured alpine tundra.

  18. Seasonal Change of Loline Alkaloids in Endophyte-lnfected Meadow Fescue

    Institute of Scientific and Technical Information of China (English)

    TONG De-wen; WANG Jin-yi; Brain Patchett; Ravi Gooneratne

    2006-01-01

    Lolines are a group of saturated pyrrolizidine alkaloids that possess broad bioactivity against a wide array of herbivorous insects. However, they do not exhibit toxicity to ruminants such as cattle and sheep. In order to study the direct and potential physiological effects on ruminants and the mechanism of insecticide/insectifuge, the distribution of loline alkaloids in endophyte-infected meadow fescue and the seasonal change of the distribution were analyzed. The crowns,roots and leaves of endophyte-infected meadow fescue at its four different growth periods, i.e., spring, summer, early autumn and late autumn, in New Zealand were colleted. After powdering, organic solvent extraction and purification by column chromatography, all loline alkaloid samples were analyzed by capillary gas chromatography with 4-phenylmorpholine (PM) as an internal standard. The analytic results showed that the loline contents in the roots, crowns and leaves of endophyte-infected meadow fescue vary with seasons. Even within the same season, the distribution of lolines in endophyte-infected meadow fescue varies. During summer, lolines mainly existed in the leaves and roots, but in early autumn, they are produced in the crowns. It was concluded that, lolines were mainly produced in the leaves and roots of endophyte-infected meadow fescue. In gas chromatographic analysis, N-formylloline, the major component of loline alkaloid in the plant, was employed to assay the alkaloids.

  19. Seed production of two meadow fescue cultivars differing in growth habit

    Directory of Open Access Journals (Sweden)

    P. MÄKELÄ

    2008-12-01

    Full Text Available Meadow fescue (Festuca pratensis Huds. is grown widely in the Nordic countries in forage grass mixtures. Locally adapted cultivars are preferred for establishment of mixed swards. Meadow fescue seed yield is determined by seed weight, the number of panicle bearing tillers, size of panicles and the number of fertile florets. We aimed to determine the differences in components of seed yield in two different meadow fescue cultivars differing in forage quality; Kalevi, released in 1979, and Fure, released in 1999. Biomass accumulation was monitored, numbers of fertile and sterile florets, and seeds were counted, and the forage quality was analysed. Seed quality was also analysed. Fure was leafier and accumulated more vegetative biomass than Kalevi. Kalevi had significantly more panicles than Fure, although Fure compensated for the lower number of panicles with increased panicle size. There were no differences in number of sterile and aborted florets between cultivars. Based on the results it seems that these two meadow fescue cultivars have a completely different strategy in seed production even though the final seed yield was not markedly different. It is apparent that meadow fescues have good ability to compensate among the components of seed yield. Long-term field experiments should be conducted to investigate the interactions between plant stand ecology, seed production and cultivation technology.;

  20. Carbon monoxide exchange and partitioning of a managed mountain meadow

    Science.gov (United States)

    Hammerle, Albin; Kitz, Florian; Spielmann, Felix; Gerdel, Katharina; Wohlfahrt, Georg

    2016-04-01

    With an average mole fraction of 100 ppb carbon monoxide (CO) plays a critical role in atmospheric chemistry and thus has an indirect global warming potential. While sources/sinks of CO on land at least partially cancel out each other, the magnitude of CO sources and sinks is highly uncertain. Even if direct CO fluxes from/to land ecosystems are very much likely clearly lower in magnitude compared to anthropogenic emissions, biomass burning, emissions from chemical precursors and the OH sink, it may be premature to neglect any direct contributions of land ecosystems to the CO budget. In addition, changes in global climate and resulting changes in global productivity may require re-evaluating older data and assumptions. One major reason for the large uncertainty is a general scarcity of empirical data. An additional factor contributing to the uncertainty is the lack of ecosystem-scale CO exchange measurements, i.e. CO flux data that encompass all sources and sinks within an ecosystem. Here we present data on continuous eddy covariance measurements of CO-fluxes above a managed mountain grassland in combination with soil chamber flux measurements, within- and above-canopy concentration profiles and an inverse Lagrangian analysis to disentangle sinks and sources of CO. Results show the grassland ecosystem to be a net source for CO during daytime, with increasing flux rates at higher solar radiation. At night, if at all, the meadow is a slight sink for CO. The same holds true regarding the soil flux measurements. Additionally, a two-month rainout experiment revealed hardly any differences in CO soil fluxes between rainout- and control-plots unless extremely dry conditions were reached.

  1. Testing for thresholds of ecosystem collapse in seagrass meadows.

    Science.gov (United States)

    Connell, Sean D; Fernandes, Milena; Burnell, Owen W; Doubleday, Zoë A; Griffin, Kingsley J; Irving, Andrew D; Leung, Jonathan Y S; Owen, Samuel; Russell, Bayden D; Falkenberg, Laura J

    2017-10-01

    Although the public desire for healthy environments is clear-cut, the science and management of ecosystem health has not been as simple. Ecological systems can be dynamic and can shift abruptly from one ecosystem state to another. Such unpredictable shifts result when ecological thresholds are crossed; that is, small cumulative increases in an environmental stressor drive a much greater change than could be predicted from linear effects, suggesting an unforeseen tipping point is crossed. In coastal waters, broad-scale seagrass loss often occurs as a sudden event associated with human-driven nutrient enrichment (eutrophication). We tested whether the response of seagrass ecosystems to coastal nutrient enrichment is subject to a threshold effect. We exposed seagrass plots to different levels of nutrient enrichment (dissolved inorganic nitrogen) for 10 months and measured net production. Seagrass response exhibited a threshold pattern when nutrient enrichment exceeded moderate levels: there was an abrupt and large shift from positive to negative net leaf production (from approximately 0.04 leaf production to 0.02 leaf loss per day). Epiphyte load also increased as nutrient enrichment increased, which may have driven the shift in leaf production. Inadvertently crossing such thresholds, as can occur through ineffective management of land-derived inputs such as wastewater and stormwater runoff along urbanized coasts, may account for the widely observed sudden loss of seagrass meadows. Identification of tipping points may improve not only adaptive-management monitoring that seeks to avoid threshold effects, but also restoration approaches in systems that have crossed them. © 2017 Society for Conservation Biology.

  2. [Diurnal and seasonal variations of energy balance over Horqin meadow].

    Science.gov (United States)

    Li, Hui-dong; Guan, De-Xin; Yuan, Feng-Hui; Ren, Yan; Wang, An-Zhi; Jin, Chang-Jie; Wu, Jia-Bing

    2014-01-01

    Based on the measurements of eddy flux and micrometeorological factors, this paper analyzed the diurnal and seasonal variations of energy balance over Horqin meadow. The results showed that annual energy balance ratio (EBR) of the eddy covariance system was 0.77, and EBR was biggest in growing season, middle in bare soil period and smallest in snow-covered period. Diurnal variations of energy components all presented bell-shaped curves. The peak of net radiation appeared around 12:00 and peaks of other components slightly lagged. Seasonal variation of net radiation presented a single-peak curve, and the annual average was 5.71 MJ x m(-2) x d(-1). Seasonal variation of latent heat flux was similar to that of net radiation, and the annual average was 2.84 MJ x m(-2) x d(-1). Seasonal variation of sensible heat flux presented a double-peak curve, and the peaks appeared in April and September, respectively. Annual averaged sensible heat flux was 1.87 MJ x m(-2) x d(-1). Maximum soil heat flux (3.47 MJ x m(-2) x d(-1)) appeared in April, and the soil heat flux became negative after September. Annual budget ratios of energy components presented a decreasing order of latent heat flux, sensible heat flux and soil heat flux, which accounted for 49.8%, 35.8% and 3.1% of net radiation, respectively. Seasonal variation of Bowen ratio (beta) presented a 'U' shape, and the annual average was 1.61. beta was small (0.18) and relatively stable in growing season, while it was large (2.39) and fluctuated severely in non-growing season.

  3. 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

  4. Complexity

    CERN Document Server

    Gershenson, Carlos

    2011-01-01

    The term complexity derives etymologically from the Latin plexus, which means interwoven. Intuitively, this implies that something complex is composed by elements that are difficult to separate. This difficulty arises from the relevant interactions that take place between components. This lack of separability is at odds with the classical scientific method - which has been used since the times of Galileo, Newton, Descartes, and Laplace - and has also influenced philosophy and engineering. In recent decades, the scientific study of complexity and complex systems has proposed a paradigm shift in science and philosophy, proposing novel methods that take into account relevant interactions.

  5. 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

    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...... 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...

  6. 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.

  7. Holocene dune formation at Ash Meadows National Wildlife Area, Nevada, USA

    Science.gov (United States)

    Lancaster, Nicholas; Mahan, Shannon

    2012-01-01

    Small isolated dune fields in the northern Mojave Desert are important centers of biodiversity and archaeological occupation sites. Currently dunes at Ash Meadows, Nevada, are stabilized by vegetation and are experiencing erosion of their upwind margins, indicating a negative sediment budget. New OSL ages from dunes at Ash Meadows indicate continuous eolian accumulation from 1.5 to 0.8 ka, with further accumulation around 0.2 ka. Prior studies (e.g., Mehringer and Warren, 1976) indicate periods of dune accumulation prior to 3.3 ka; 1.9–1 ka; and after 0.9 ka. These periods of eolian accumulation are largely synchronous with those identified elsewhere in the Mojave Desert. The composition of the Ash Meadows dunes indicates their derivation from regional fluvial sources, most likely during periods when axial washes were active as a result of enhanced winter precipitation.

  8. 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.

  9. Impact of the brine from a desalination plant on a shallow seagrass ( Posidonia oceanica) meadow

    Science.gov (United States)

    Gacia, Esperança; Invers, Olga; Manzanera, Marta; Ballesteros, Enric; Romero, Javier

    2007-05-01

    Although seawater desalination has increased significantly over recent decades, little attention has been paid to the impact of the main by-product (hypersaline water: brine) on ecosystems. In the Mediterranean, potentially the most affected ecosystems are meadows of the endemic seagrass Posidonia oceanica. We studied the effect of brine on a shallow P. oceanica meadow exposed to reverse osmosis brine discharge for more than 6 years. P. oceanica proved to be very sensitive to both eutrophication and high salinities derived from the brine discharge. Affected plants showed high epiphyte load and nitrogen content in the leaves, high frequencies of necrosis marks, low total non-structural carbohydrates and low glutamine synthetase activity, compared to control plants. However, there was no indication of extensive decline of the affected meadow. This is probably due to its very shallow situation, which results in high incident radiation as well as fast dilution and dispersion of the brine plume.

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

    Science.gov (United States)

    Tol, Samantha J; Coles, Rob G; Congdon, Bradley C

    2016-01-01

    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.

  11. 75 FR 26747 - Meadow Lake Wind Farm III LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Science.gov (United States)

    2010-05-12

    ...-1176-000] Meadow Lake Wind Farm III LLC; Supplemental Notice That Initial Market-Based Rate Filing... above-referenced proceeding of Meadow Lake Wind Farm III LLC's application for market-based rate... clicking on the appropriate link in the above list. They are also available for review in the Commission's...

  12. 75 FR 26747 - Meadow Lake Wind Farm IV LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Science.gov (United States)

    2010-05-12

    ...] Meadow Lake Wind Farm IV LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes Request...-referenced proceeding of Meadow Lake Wind Farm IV LLC's application for market-based rate authority, with an... proceeding are accessible in the Commission's eLibrary system by clicking on the appropriate link in the...

  13. RESEARCH REGARDING THE MELLIFEROUS CHARACTHERISTICS OF LABIATES FROM XEROPHILE MEADOWS FROM DANUBE VALLEY

    Directory of Open Access Journals (Sweden)

    NICOLETA ION

    2013-12-01

    Full Text Available The xerophile meadows in the Danube Valley are dry meadows, located at a great distance from the Danube and with underground waters at greater depth. Their floral composition is characterized by a small number of species pertaining to both mezoxerophiles and to xerophiles, yet the highest percentage is covered by xerophile species, which are characterized by their small foliage surface, the very narrow and tough limb, and acute porosity etc.In the floral composition of these species, the graminaceae species are best represented, followed by leguminous and lamiaceae, known in beekeeping as good honey plants. Thus, the researches carried out have shown that Lamiaceae species have a good participation, with variation limits raging from 15% to 50-60%. Leguminous species are represented less on xerophile meadows than in hidrophile meadows. Among these we mention: Lotus corniculatus L., Trifolium repens L. si Medicago lupulina L., all these species being known in beekeeping as good honey plants. Among gramineae species the most representatives are: Lolium perene L. and Poa pratensis L., yet with no melliferous value. Likewise, the group of „various” plants varied a lot as participation in the structure of the vegetal cover of xerophile meadows, depending on the place of research, all these species having no melliferous value. The current paper describes the results o biometric and melliferous researches carried out over the period 2003- 2005 on 5 plant species pertaining to the Lamiaceae family, namely: Salvia nemerosa L. – sage; Salvia pratensis L. – meadow sage; Marrubium vulgare L. – horehound;Lamium purpureum L. – purple deatnettle;Lamium amplexicaule L. – henbit deadnettle.

  14. A comparison between energy transfer and atmospheric turbulent exchanges over alpine meadow and banana plantation

    Science.gov (United States)

    Ding, Zhangwei; Ma, Yaoming; Wen, Zhiping; Ma, Weiqiang

    2016-04-01

    Banana plantation and alpine meadow ecosystems in southern China and the Tibetan Plateau are unique in the underlying surfaces they exhibit. In this study, we used eddy covariance and a micrometeorological tower to examine the characteristics of land surface energy exchanges over a banana plantation in southern China and an alpine meadow in the Tibetan Plateau from May 2010 to August 2012. The results showed that the diurnal and seasonal variations in upward shortwave radiation flux and surface soil heat flux were larger over the alpine meadow than over the banana plantation surface. Dominant energy partitioning varied with season. Latent heat flux was the main consumer of net radiation flux in the growing season, whereas sensible heat flux was the main consumer during other periods. The Monin-Obukhov similarity theory was employed for comparative purposes, using sonic anemometer observations of flow over the surfaces of banana plantations in the humid southern China monsoon region and the semi-arid areas of the TP, and was found to be applicable. Over banana plantation and alpine meadow areas, the average surface albedo and surface aerodynamic roughness lengths under neutral atmospheric conditions were ~0.128 and 0.47m, and ~0.223 and 0.01m, respectively. During the measuring period, the mean annual bulk transfer coefficients for momentum and sensible heat were 1.47×10-2 and 7.13×10-3, and 2.91×10-3 and 1.96×10-3, for banana plantation and alpine meadow areas, respectively. This is the first time in Asia that long-term open field measurements have been taken with the specific aim of making comparisons between banana plantation and alpine meadow surfaces.

  15. Evaluating mountain meadow groundwater response to Pinyon-Juniper and temperature in a great basin watershed

    Science.gov (United States)

    Carroll, Rosemary W.H.; Huntington, Justin L.; Snyder, Keirith A.; Niswonger, Richard G.; Morton, Charles; Stringham, Tamzen K.

    2017-01-01

    This research highlights development and application of an integrated hydrologic model (GSFLOW) to a semiarid, snow-dominated watershed in the Great Basin to evaluate Pinyon-Juniper (PJ) and temperature controls on mountain meadow shallow groundwater. The work used Google Earth Engine Landsat satellite and gridded climate archives for model evaluation. Model simulations across three decades indicated that the watershed operates on a threshold response to precipitation (P) >400 mm/y to produce a positive yield (P-ET; 9%) resulting in stream discharge and a rebound in meadow groundwater levels during these wetter years. Observed and simulated meadow groundwater response to large P correlates with above average predicted soil moisture and with a normalized difference vegetation index threshold value >0.3. A return to assumed pre-expansion PJ conditions or an increase in temperature to mid-21st century shifts yielded by only ±1% during the multi-decade simulation period; but changes of approximately ±4% occurred during wet years. Changes in annual yield were largely dampened by the spatial and temporal redistribution of evapotranspiration across the watershed: Yet the influence of this redistribution and vegetation structural controls on snowmelt altered recharge to control water table depth in the meadow. Even a small-scale removal of PJ (0.5 km2) proximal to the meadow will promote a stable, shallow groundwater system resilient to droughts, while modest increases in temperature will produce a meadow susceptible to declining water levels and a community structure likely to move toward dry and degraded conditions.

  16. An Assessment of Storage Terms in the Surface Energy Balance of a Subalpine Meadow in Northwest China

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The heat storage terms in the soil-vegetation-atmosphere system may play an important role in the surface energy budget.In this paper,we evaluate the heat storage terms of a subalpine meadow based on a ficld experiment conducted in the complex terrain of the eastern Qilian Mountains of Northwest China and their impact on the closure of the surface energy balance under such non-ideal conditions.During the night, the average sum of the storage terms was -5.5 W m~(-2),which corresponded to 10.4%of net radiation.The sum of the terms became positive at 0730 LST and negative again at about 1500 LST,with a maximum value of 19 W m~(-2) observed at approximately 0830 LST.During the day,the average of the sum of the storage terms was 6.5 W m~(-2),which corresponded to 4.0%of net radiation.According to the slopes obtained when linear regression of the net radiation and partitioned fluxes was forced through the origin,there is an imbalance of 14.0%in the subalpine meadow when the storage terms are not considered in the surface energy balance.This imbalance was improved by 3.4%by calculating the sum of the storage terms.The soil heat storage flux gave the highest contribution(1.59%),while the vegetation enthalpy change and the rest of the storage terms were responsible for improvements of 1.04%and 0.77%,respectively.

  17. An Assessment of Storage Terms in the Surface Energy Balance of a Subalpine Meadow in Northwest China

    Institute of Scientific and Technical Information of China (English)

    WANG Runyuan; ZHANG Qiang

    2011-01-01

    The heat storage terms in the soil-vegetation-atmosphere system may play an important role in the surface energy budget. In this paper, we evaluate the heat storage terms of a subaipine meadow based on a field experiment conducted in the complex terrain of the eastern Qilian Mountains of Northwest China and their impact on the closure of the surface energy balance under such non-ideal conditions. During the night,the average sum of the storage terms was -5.5 W m-2, which corresponded to 10.4% of net radiation. The sum of the terms became positive at 0730 LST and negative again at about 1500 LST, with a maximum value of 19 W m-2 observed at approximately 0830 LST. During the day, the average of the sum of the storage terms was 6.5 W m-2, which corresponded to 4.0% of net radiation. According to the slopes obtained when linear regression of the net radiation and partitioned fluxes was forced through the origin, there is an imbalance of 14.0% in the subalpine meadow when the storage terms are not considered in the surface energy balance. This imbalance was improved by 3.4% by calculating the sum of the storage terms. The soil heat storage flux gave the highest contribution (1.59%), while the vegetation enthalpy change and the rest of the storage terms were responsible for improvements of 1.04% and 0.77%, respectively.

  18. 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.

  19. [Effects of nitrogen and phosphorous fertilization on community structure and productivity of degraded alpine meadows in northern Tibet, China].

    Science.gov (United States)

    Zong, Ning; Shi, Pei-li; Niu, Ben; Jiang, Jing; Song, Ming-hua; Zhang, Xian-zhou; He, Yong-tao

    2014-12-01

    Abstract: Fertilization is an effective management measure for recovery of degraded grasslands. To better understand the effects of fertilization on community structure and productivity of lightly and severely degraded alpine meadows, we conducted a fertilization experiment in northern Tibet since 2008. The treatments were addition of nitrogen (N) alone (50 kg N x hm(-2) x a(-1), LN; 100 kg N x hm(-2) x a(-1), HN) or addition of both phosphorus (P) and N (50 kg N x hm(-2) x a(-1) +50 kg P x hm(-2) x a(-1), LN+P; 100 kg N x hm(-2) x a(-1) +50 kg P x hm(-2) x a(-1), HN+P) in each of the two types of degraded alpine meadows. N addition alone significantly affected plant community coverage or productivity in neither the slightly nor the severely degraded alpine meadow, while addition of both N and P significantly increased plant community coverage, aboveground and below- ground biomass of the alpine meadows. This suggested that productivity of this alpine meadow is co-limited by N and P. HN and HN+P significantly decreased species richness and evenness in the lightly degraded grassland, indicating that HN was not beneficial for the lightly degraded grassland to maintain species diversity and community stability. N addition significantly reduced the root to shoot ratio in the severely degraded meadow. In the lightly degraded meadow, N addition alone, especially with a high amount (HN) , enhanced the importance values (IV) and biomass of grasses, while fertilization with both N and P increased those of sedges. In the severely degraded meadow, fertilization had little effect on IV of grasses or sedges, but improved biomass of forbs. The results suggested that LN+P could be employed in recovery of lightly degraded alpine meadows, but other management measures such as fencing and reseeding may be needed for recovery of severely degraded alpine meadows.

  20. Complex

    African Journals Online (AJOL)

    CLEMENT O BEWAJI

    Schiff bases and their complex compounds have been studied for their .... establishing coordination of the N–(2 – hydroxybenzyl) - L - α - valine Schiff base ..... (1967); “Spectrophotometric Identification of Organic Compounds”, Willey, New.

  1. Spatial variability of soil N2O and CO2 fluxes in different topographic positions in a tropical montane forest in Kenya

    Science.gov (United States)

    Arias-Navarro, C.; Díaz-Pinés, E.; Klatt, S.; Brandt, P.; Rufino, M. C.; Butterbach-Bahl, K.; Verchot, L. V.

    2017-03-01

    Quantifying and understanding the small-scale variability of nitrous oxide (N2O) and carbon dioxide (CO2) emission are essential for reporting accurate ecosystem greenhouse gas budgets. The objective of this study was to evaluate the spatial pattern of soil CO2 and N2O emissions and their relation to topography in a tropical montane forest. We measured fluxes of N2O and CO2 from 810 sampling locations across valley bottom, midslope, and ridgetop positions under controlled laboratory conditions. We further calculated the minimum number of samples necessary to provide best estimates of soil N2O and CO2 fluxes at the plot level. Topography exhibited a major influence on N2O emissions, with soils at midslope position emitting significantly less than at ridgetops and valley bottoms, but no consistent effect of topography on soil CO2 emissions was found. The high spatial variation of N2O and CO2 fluxes was further increased by changes in vegetation and soil properties resulting from human disturbance associated with charcoal production. Soil N2O and CO2 fluxes showed no spatial pattern at the plot level, with "hot spots" strongly contributing to the total emissions (10% of the soil cores represented 73 and 50% of the total N2O and CO2 emissions, respectively). Thus, a large number of samples are needed to obtain robust estimates of N2O and CO2 fluxes. Our results highlight the complex biogeochemical cycling in tropical montane forests, and the need to carefully address it in research experiments to robustly estimate soil CO2 and N2O fluxes at the ecosystem scale.

  2. 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

  3. 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.

  4. Facilitating adaptation in montane plants to changing precipitation along an elevation gradient

    Science.gov (United States)

    Hess, Steve; Leopold, Christina

    2017-01-01

    Montane plant communities throughout the world have responded to changes in precipitation and temperature regimes by shifting ranges upward in elevation. Continued warmer, drier climate conditions have been documented and are projected to increase in high-elevation areas in Hawai‘i, consistent with climate change effects reported in other environments throughout the world. Organisms that cannot disperse or adapt biologically to projected climate scenarios in situ may decrease in distributional range and abundance over time. Restoration efforts will need to accommodate future climate change and account for the interactive effects of existing invasive species to ensure long-term persistence. As part of a larger, ongoing restoration effort, we hypothesized that plants from a lower-elevation forest ecotype would have higher rates of survival and growth compared to high-elevation forest conspecifics when grown in common plots along an elevation gradient. We monitored climate conditions at planting sites to identify whether temperature or rainfall influenced survival and growth after 20 weeks. We found that origin significantly affected survival in only one of three native montane species, Dodonaea viscosa. Contrary to our hypothesis, 75.2% of seedlings from high-elevation origin survived in comparison to 58.7% of seedlings from low elevation across the entire elevation gradient. Origin also influenced survival in linearized mixed models that controlled for temperature, precipitation, and elevation in D. viscosa and Chenopodium oahuense. Only C. oahuense seedlings had similar predictors of growth and survival. There were no common patterns of growth or survival between species, indicating that responses to changing precipitation and emperature regimes varied between montane plant species. Results also suggest that locally sourced seed is important to ensure highest survival at restoration sites. Further experimentation on larger spatial and temporal scales is necessary

  5. Effects of mist acidity and ambient ozone removal on montane red spruce

    Energy Technology Data Exchange (ETDEWEB)

    Vann, D.R. [Pennsylvania Univ., Philadelphia, PA (United States). Dept. of Biology; Strimbeck, D.R.; Johnson, A.H. [Pennsylvania Univ., Philadelphia, PA (United States). Dept. of Geology

    1995-10-01

    The effects of acidic mists and ozone on several biochemical and growth parameters in mature montane red spruce were examined. Branch-size environmental chambers were used to introduce mists of controlled composition and to protect selected branches from ambient ozone and acidic mists. Mists of distilled water increased the end-of-season pigment concentration and shoot length of enclosed branches relative to ambient or artificial mists. Needle and twig weights and starch concentrations were not significantly altered by the acidic mist treatments. Removal of ambient ozone had no apparent effect on the variables measured. 8 figs., 2 tabs., 39 refs.

  6. Army ant raid attendance and bivouac checking behavior by Neotropical montane forest birds

    OpenAIRE

    O'Donnell, Sean; Kumar, Anjali; Logan, Corina J.

    2010-01-01

    This is the final version of the article. It first appeared from Wilson Ornithological Society via http://dx.doi.org/10.1676/09-156.1 We quantified resident and migrant bird attendance at army ant swarm raids (n  =  48) in a neotropical montane forest. All observations were during seasons when Nearctic migrant birds are present. Bird species differed in army ant raid-attending behavior. Resident bird species attended 2 to 54% of raids, while migrants attended at lower maximum frequencies (...

  7. Tropical land-cover change alters biogeochemical inputs to ecosystems in a Mexican montane landscape.

    Science.gov (United States)

    Ponette-González, A G; Weathers, K C; Curran, L M

    2010-10-01

    In tropical regions, the effects of land-cover change on nutrient and pollutant inputs to ecosystems remain poorly documented and may be pronounced, especially in montane areas exposed to elevated atmospheric deposition. We examined atmospheric deposition and canopy interactions of sulfate-sulfur (SO4(2-)-S), chloride (Cl-), and nitrate-nitrogen (NO(3-)-N) in three extensive tropical montane land-cover types: clearings, forest, and coffee agroforest. Bulk and fog deposition to clearings was measured as well as throughfall (water that falls through plant canopies) ion fluxes in seven forest and five coffee sites. Sampling was conducted from 2005 to 2008 across two regions in the Sierra Madre Oriental, Veracruz, Mexico. Annual throughfall fluxes to forest and coffee sites ranged over 6-27 kg SO4(2-)-S/ha, 12-69 kg Cl-/ha, and 2-6 kg NO(3-)-N/ha. Sulfate-S in forest and coffee throughfall was higher or similar to bulk S deposition measured in clearings. Throughfall Cl- inputs, however, were consistently higher than Cl- amounts deposited to cleared areas, with net Cl- fluxes enhanced in evergreen coffee relative to semi-deciduous forest plots. Compared to bulk nitrate-N deposition, forest and coffee canopies retained 1-4 kg NO(3-)-N/ha annually, reducing NO(3-)-N inputs to soils. Overall, throughfall fluxes were similar to values reported for Neotropical sites influenced by anthropogenic emissions, while bulk S and N deposition were nine- and eightfold greater, respectively, than background wet deposition rates for remote tropical areas. Our results demonstrate that land-cover type significantly alters the magnitude and spatial distribution of atmospheric inputs to tropical ecosystems, primarily through canopy-induced changes in fog and dry deposition. However, we found that land cover interacts with topography and climate in significant ways to produce spatially heterogeneous patterns of anion fluxes, and that these factors can converge to create deposition hotspots

  8. La Casa Roura de Domènech i Montaner a Canet de Mar (1892)

    OpenAIRE

    Borrell Mas, Jordi

    2010-01-01

    La Casa Roura o ca la Bianga de Canet de Mar va ser construïda i projectada per l’arquitecte Lluís Domènech i Montaner durant els anys 1889 i 1892 per encàrrec de la seva cunyada Francesca Roura i el seu marit Jacint de Capmany. Aquells van ser els primers anys del nou moviment cultural i arquitectònic anomenat Modernisme que s’estava desenvolupant a Catalunya. Paral•lelament, arreu d’Europa també s’hi estaven produint diferents moviments com l’Art Noveau, la Sezession, el Jugendstil o l’Styl...

  9. Mapping of seagrass meadows from the Lakshadweep Islands (India), using aerial photographs

    Digital Repository Service at National Institute of Oceanography (India)

    Jagtap, T.G.; Inamdar, S.N.

    Seagrass meadows from the Lakshadweep Islands were mapped with the help of black and white aerial photographs. A maximum of 40 ha seagrass cover was estimated in the lagoon of Minicoy, followEd. by Kavaratti (43 ha.). The total seagrass cover from...

  10. Methods of limiting willow shrub re-growth after initial removal on fen meadows

    NARCIS (Netherlands)

    Klimkowska, Agata; Dzierza, Paulina; Kotowski, Wiktor; Brzezinska, Kamila

    2010-01-01

    Shrub removal is commonly used for management and restoration of species-rich fen meadows. A common problem after initial shrub cutting of willow is a vigorous re-sprouting and quick re-growth. In this paper we test experimentally what is an effective management option, limiting the re-growth of wil

  11. 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.

  12. Evaluating mountain meadow groundwater response to pinyon-juniper and temperature in a great basin watershed

    Science.gov (United States)

    Expansion of deeply-rooted Pinyon-Juniper (PJ) has altered water partitioning and reduced water availability to discharging meadows. Research highlights the development and application of GSFLOW to a semi-arid, snow-dominated watershed in the Great Basin to evaluate PJ and temperature controls on mo...

  13. [Microbial community structure of the alpine meadow under different grazing styles in Naqu prefecture of Tibet].

    Science.gov (United States)

    Niu, Lei; Liu, Ying-hui; Li, Yue; Ouyang, Sheng-nan

    2015-08-01

    To clarify the effects of grazing styles on the soil microbial community in the alpine meadow, we explored the changes of soil microbial community structure in the alpine meadow located in Naqu district of Tibet Autonomous Region by analyzing the soil chemical properties and phospholipid fatty acids (PLFAs). The results showed that the contents of soil total organic carbon, total phosphate and nitrate nitrogen under the different grazing styles followed the trend of 7-year rest grazing > free grazing > grazing prohibition. Except for the ratio of fungal PLFAs/bacterial PLFAs, total PLFAs, the bacterial PLFAs, the fungal PLFAs, the gram negative bacterial and the gram positive bacterial PLFAs over the different grazing types were in the order of 7-year rest grazing > 5-year grazing prohibition > 7-year and 9-year grazing prohibition. The principal component analysis (PCA) presented that the first principal component (PC1 = 74.6%) was mainly composed of monounsaturated fatty acids, polyunsaturated fatty acids and branched fatty acids, and the second principal component (PC2 = 13.2%) was mainly composed of saturated fatty acids and some monounsaturated fatty acids. Total PLFAs content was significantly positively correlated with microbial biomass carbon content. Compared with grazing prohibition, fallow grazing was best for the alpine meadow in Naqu district, and free grazing with light intensity was good for the alpine meadow.

  14. 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.

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

    Data.gov (United States)

    US Fish and Wildlife Service, 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...

  16. 75 FR 39037 - Crane Meadows National Wildlife Refuge, Morrison County, MN

    Science.gov (United States)

    2010-07-07

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Fish and Wildlife Service Crane Meadows National Wildlife Refuge, Morrison County, MN AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice of availability: Draft comprehensive conservation plan and...

  17. 75 FR 63505 - Crane Meadows National Wildlife Refuge, Morrison County, MN

    Science.gov (United States)

    2010-10-15

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Fish and Wildlife Service Crane Meadows National Wildlife Refuge, Morrison County, MN AGENCY: U.S. Fish and Wildlife Service, Department of the Interior. ACTION: Notice of availability: Final Comprehensive...

  18. 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.

  19. 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)

  20. Methods of limiting willow shrub re-growth after initial removal on fen meadows

    NARCIS (Netherlands)

    Klimkowska, Agata; Dzierza, Paulina; Kotowski, Wiktor; Brzezinska, Kamila

    2010-01-01

    Shrub removal is commonly used for management and restoration of species-rich fen meadows. A common problem after initial shrub cutting of willow is a vigorous re-sprouting and quick re-growth. In this paper we test experimentally what is an effective management option, limiting the re-growth of wil

  1. Grade 9 Astronomy Study: Interests of Boys and Girls Studying Astronomy at Fletcher's Meadow Secondary School

    Science.gov (United States)

    Krstovic, Mirjan; Brown, Laura; Chacko, Merin; Trinh, Brenda

    2008-01-01

    In this report, we discuss the interests of Grade 9 boys and girls studying astronomy at Fletcher's Meadow Secondary School in Brampton, Ontario. A total of 152 Grade 9 academic students were asked to rate their interest levels in various astronomy topics on a scale of 0-3, where 0 represented no interest and 3 represented a high level of…

  2. Let it flow: how does an underlying current affect wave propagation over a natural seagrass meadow?

    NARCIS (Netherlands)

    Paul, M.; Gillis, L.G.

    2015-01-01

    Temperate seagrass beds can be found within intertidal and tidal areas of variable hydrodynamic forcing. To investigate the interaction between hydrodynamics and seagrass plants, Zostera noltii meadows were exposed to a range of combinations of waves and flow in a flume. Velocity profiles were obtai

  3. Seed dispersal in agricultural habitats and the restoration of species-rich meadows.

    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 nutrient-poor so

  4. Short-term effect of beach replenishment on a shallow Posidonia oceanica meadow.

    Science.gov (United States)

    González-Correa, José M; Fernández-Torquemada, Yolanda; Sánchez-Lizaso, José Luis

    2009-09-01

    Putative perturbations on a Posidonia oceanica meadow produced by recent artificial beach nourishment were evaluated in relation to four undisturbed meadows. Temporal variations of putative impacted location vs. control locations of environmental (light availability and sediment features), plant (associated epiphytes, silt-clay fraction attached to epiphytes, herbivore attack, non-structural carbohydrate reserves) and structural parameters (cover and density) of meadows were tested by asymmetrical analysis of variance beyond BACI (Before/After, Control/Impact). Additionally, two asymmetrical analyses of variance were used to test for differences in vegetative growth of horizontal rhizomes (leaf production, horizontal rhizome growth, biomass production and net secondary rhizome recruitment) before and after beach replenishment. Environmental effects induced by dumping works were only detected in connection with a higher silt-clay deposition rate. This increase was consistent with the increase of silt-clay cover attached to epiphytes. As a consequence of silt-clay smothering, a decrease of filter feeding epiphytes, starch reserves, shoot surface and shoot biomass was observed. The sensitivity of plants to sediment inputs, leads us to recommend avoidance of dumping or sediment movement in the vicinity of P. oceanica meadows.

  5. Fen-meadow succession in relation to spatial and temporal differences in hydrological and soil conditions

    NARCIS (Netherlands)

    Hoek, van der D.; Sykora, K.V.

    2006-01-01

    Question: In fen meadows with Junco-Molinion plant communities, falling groundwater levels may not lead to a boosted above-ground biomass production if limitation of nutrients persists. Instead, depending on drainage intensity and microtopography, acidification may trigger a shift into drier and mor

  6. Grade 9 Astronomy Study: Interests of Boys and Girls Studying Astronomy at Fletcher's Meadow Secondary School

    Science.gov (United States)

    Krstovic, Mirjan; Brown, Laura; Chacko, Merin; Trinh, Brenda

    2008-01-01

    In this report, we discuss the interests of Grade 9 boys and girls studying astronomy at Fletcher's Meadow Secondary School in Brampton, Ontario. A total of 152 Grade 9 academic students were asked to rate their interest levels in various astronomy topics on a scale of 0-3, where 0 represented no interest and 3 represented a high level of…

  7. Processes affecting the spatial distribution of seagrass meadow sedimentary material on Yao Yai Island, Thailand

    Science.gov (United States)

    Quak, Michelle S. Y.; Ziegler, Alan D.; Benner, Shawn G.; Evans, Sam; Todd, Peter A.; Gillis, Lucy G.; Vongtanaboon, Sukanya; Jachowski, Nick; Bouma, Tjeerd J.

    2016-12-01

    Many islands throughout SE Asia are experiencing rapid development and land-cover conversion that potentially threaten sensitive coastal ecosystems, such as seagrasses, through increased loading of sediment and nutrients originating from disturbed catchments draining to the sea. To evaluate this threat for one such island in Southern Thailand (Yao Yai), we perform sediment source tracing via end-member mixing analysis using stable isotopes δ13C and δ15N in organic matter to explore sediment loading in a seagrass meadow. The analysis indicates that sedimentary material in the meadow originates mostly from ocean-associated sources (∼62% from seagrass detritus, seston, and ocean sediments). Terrestrial material comprises ∼19% of the organic material found in the seagrass meadow, with another 20% originating from an adjacent mangrove forest. Approximately one-fourth of the seagrass meadow material (24%) is detritus that has been (re)deposited internally. The high contribution of terrestrial-derived organic matter deposited near the river mouth demonstrates that substantial quantities of sediment are being transferred from upslope erosion sources into the seagrass meadow. However, only a small amount of this material is deposited throughout the entire bay because much of the terrestrial- and mangrove-derived sediment is transferred to the open ocean via channels that are periodically dredged to allow boat access to two small inland harbours. This positive affect of dredging has not received very much attention in existing literature. River water flowing to the channels during falling tide delivers sediment to these efficient pathways, where much of it bypasses the seagrass meadow at periods of time when sediment deposition would normally be the greatest. There is growing concern that ongoing land-cover changes and planned urbanization related to tourism and agriculture on the island may boost sediment/nutrients above a critical threshold, beyond that revealed in

  8. 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

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

    Directory of Open Access Journals (Sweden)

    Damien M Hicks

    Full Text Available 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

  10. 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

  11. 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

  12. Seasonality in vegetation biometrics and its effects on sediment characteristics and meiofauna in Baltic seagrass meadows

    Science.gov (United States)

    Jankowska, Emilia; Włodarska-Kowalczuk, Maria; Kotwicki, Lech; Balazy, Piotr; Kuliński, Karol

    2014-02-01

    Seagrass meadows can act as ecosystem engineers, i.e., organisms that modify the availability of resources to other organisms. However, their possible positive impacts depend on the characteristics of the vegetation, and these can vary strongly seasonally. This study assesses seasonal variability in macrophyte taxonomic composition and seagrass biometrics in the temperate Baltic Sea eelgrass meadows. We hypothesize that the anticipated strong seasonality in vegetation cover induces parallel seasonal changes in seagrass engineering effects as indicated by changes in sediment characteristics and meiozoobenthic abundance, composition and diversity. Macrophytes, sediments, and fauna were sampled at two locations in the Puck Bay from vegetated bottoms and bare sands five times in one year. Zostera marina vegetation occurred throughout the year and showed strong seasonality with the highest values of shoot density, leaf length, and biomass in July (202.3 ± 30.0 95% CI shoots m-2) and the lowest in March (55.4 ± 15.0 shoots m-2). POC was significantly higher in vegetated sands, and these effects were evident throughout the study period regardless of variability in macrophyte vegetation. The density and diversity of meiofauna did not differ between the seagrass beds and bare sands even in summer months when vegetation was best developed. The lack of an effect of the seagrass meadows on the meiofauna can be explained by the relatively low shoot density and biomass of the studied seagrass meadows and/or higher macrobenthic predation on the vegetated bottom compared to bare sands. However, both the canopies of macrophytes and the effects of the vegetation on benthic systems could increase substantially over the course of the gradual, natural restoration of the seagrass meadows.

  13. Soil organic carbon storage and soil CO2 flux in the alpine meadow ecosystem

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    High-resolution sampling,measurements of organic carbon contents and 14C signatures of selected four soil profiles in the Haibei Station situated on the northeast Tibetan Plateau,and application of 14C tracing technology were conducted in an attempt to investigate the turnover times of soil organic car-bon and the soil-CO2 flux in the alpine meadow ecosystem. The results show that the organic carbon stored in the soils varies from 22.12×104 kg C hm-2 to 30.75×104 kg C hm-2 in the alpine meadow eco-systems,with an average of 26.86×104 kg C hm-2. Turnover times of organic carbon pools increase with depth from 45 a to 73 a in the surface soil horizon to hundreds of years or millennia or even longer at the deep soil horizons in the alpine meadow ecosystems. The soil-CO2 flux ranges from 103.24 g C m-2 a-1 to 254.93 gC m-2 a-1,with an average of 191.23 g C m-2 a-1. The CO2 efflux produced from microbial decomposition of organic matter varies from 73.3 g C m-2 a-1 to 181 g C m-2 a-1. More than 30% of total soil organic carbon resides in the active carbon pool and 72.8%―81.23% of total CO2 emitted from or-ganic matter decomposition results from the topsoil horizon (from 0 cm to 10 cm) for the Kobresia meadow. Responding to global warming,the storage,volume of flow and fate of the soil organic carbon in the alpine meadow ecosystem of the Tibetan Plateau will be changed,which needs further research.

  14. Influence of land cover changes on the physical and chemical properties of alpine meadow soil

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Taking the alpine cold meadow grassland in the southeastern part of the Qinghai-Tibetan Plateau as an example, this research deals with the characteristics of alpine meadow soil property changes, including soil nutrients, soil physical properties and soil moisture content under different land coverage conditions. With the degradation of grassland vegetation and the decline of vegetation coverage, soil compactness reduces, gravel content increases and bulk density increases. The originally dense root-system layer is gradually denuded, making the soil coarse and gravel. The change of the organic matter contents with the vegetation coverage change in the surface soil layer (0-20 cm) has shown an obvious cubic polynomial curve process. The organic matter contents increase rapidly when land coverage is above 60%, contrarily decreases on a large scale when land coverage is below 30%. Between 30%-60% of land coverage the organic matter contents remain stable. The total N and organic matter contents in soil have shown quite similar change regularity. Following this the mathematic equations are derived to describe such change processes. Moisture content in soil changes sharply with the vegetation coverage change. Soil moisture content change with the vegetation coverage change has shown a quadratic parabola process. Results have shown that organic matter content and the total N content of the alpine meadow soil decrease by 14890 kg/hm2 and 5505 kg/hm2 respectively as the vegetation coverage reduces from 90% to less than 30%. The heavy changes of soil physical and chemical properties with grassland degradation have made the recovery of alpine meadow ecological system impossible. The protection of alpine meadow vegetation is of vital importance to the maintenance of the regional soil environment and the regional ecological system.

  15. Soil organic carbon storage and soil CO2 flux in the alpine meadow ecosystem

    Institute of Scientific and Technical Information of China (English)

    TAO Zhen; SHEN ChengDe; GAO QuanZhou; SUN YanMin; YI WeiXi; LI YingNian

    2007-01-01

    High-resolution sampling, measurements of organic carbon contents and 14C signatures of selected four soil profiles in the Haibei Station situated on the northeast Tibetan Plateau, and application of 14C tracing technology were conducted in an attempt to investigate the turnover times of soil organic carbon and the soil-CO2 flux in the alpine meadow ecosystem. The results show that the organic carbon stored in the soils varies from 22.12(104 kg C hm-2 to 30.75(104 kg C hm-2 in the alpine meadow ecosystems, with an average of 26.86(104 kg C hm-2. Turnover times of organic carbon pools increase with depth from 45 a to 73 a in the surface soil horizon to hundreds of years or millennia or even longer at the deep soil horizons in the alpine meadow ecosystems. The soil-CO2 flux ranges from 103.24 g C m-2 a-1 to 254.93 gC m-2 a-1, with an average of 191.23 g C m-2 a-1. The CO2 efflux produced from microbial decomposition of organic matter varies from 73.3 g C m-2 a-1 to 181 g C m-2 a-1. More than 30% of total soil organic carbon resides in the active carbon pool and 72.8%-81.23% of total CO2 emitted from organic matter decomposition results from the topsoil horizon (from 0 cm to 10 cm) for the Kobresia meadow. Responding to global warming, the storage, volume of flow and fate of the soil organic carbon in the alpine meadow ecosystem of the Tibetan Plateau will be changed, which needs further research.

  16. Identifying Components of Groundwater Flow, Flux, and Storage in Tuolumne Meadows, Yosemite, California

    Science.gov (United States)

    Vialpando, M., III; Lowry, C.; Visser, A.; Moran, J. E.; Esser, B. K.

    2015-12-01

    High elevation meadows in the Sierra Nevada of California, USA represent mixing zones between surface water and groundwater. Quantifying the exchange between stream water and groundwater, and the residence time of water stored in meadow sediments will allow examination of the possible buffer effect that groundwater has on meadows and streams. This in turn has implications for the resilience of the ecosystem as well as the downstream communities that are dependent upon runoff for water supply. Stream flow was measured and water samples were collected along a 5 km reach of the Tuolumne River and adjacent wells during both spring runoff and baseflow. Water samples were analyzed for concentrations of dissolved noble gases and anions, sulfur-35, tritium and radon to study surface water-groundwater interactions and residence times. Although lower than average because of the ongoing drought in California, discharge in early July 2015 was about 35 times that measured during the previous fall. During baseflow, a small component of fracture flow (2%) is identified using dissolved helium. Radon, anions and stream discharge identify reaches of groundwater discharge. Anions show a steady increase in the groundwater component over the western portion of the meadow during baseflow, and over 50% of stream water is exchanged with meadow groundwater, without a net gain or loss of stream flow. Sulfur-35 and tritium results indicated that groundwater contributing to stream flow has recharged within the previous two years. With the current drought, estimated as the most severe in 1200 years, accurate estimations of water availability are becoming increasingly important to water resource managers.

  17. 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.

  18. Influence of climate on the presence of colour polymorphism in two montane reptile species.

    Science.gov (United States)

    Broennimann, Olivier; Ursenbacher, Sylvain; Meyer, Andreas; Golay, Philippe; Monney, Jean-Claude; Schmocker, Hans; Guisan, Antoine; Dubey, Sylvain

    2014-11-01

    The coloration of ectotherms plays an important role in thermoregulation processes. Dark individuals should heat up faster and be able to reach a higher body temperature than light individuals and should therefore have benefits in cool areas. In central Europe, montane local populations of adder (Vipera berus) and asp viper (Vipera aspis) exhibit a varying proportion of melanistic individuals. We tested whether the presence of melanistic V. aspis and V. berus could be explained by climatic conditions. We measured the climatic niche position and breadth of monomorphic (including strictly patterned individuals) and polymorphic local populations, calculated their niche overlap and tested for niche equivalency and similarity. In accordance with expectations, niche overlap between polymorphic local populations of both species is high, and even higher than that of polymorphic versus monomorphic montane local populations of V. aspis, suggesting a predominant role of melanism in determining the niche of ectothermic vertebrates. However, unexpectedly, the niche of polymorphic local populations of both species is narrower than that of monomorphic ones, indicating that colour polymorphism does not always enable the exploitation of a greater variability of resources, at least at the intraspecific level. Overall, our results suggest that melanism might be present only when the thermoregulatory benefit is higher than the cost of predation.

  19. Community dynamics of a montane Fagus engleriana–Cyclobalanopsis multiervis mixed forest in Shennongjia, Hubei, China

    Directory of Open Access Journals (Sweden)

    Jielin Ge

    2012-11-01

    Full Text Available Montane evergreen and deciduous broad-leaved mixed forests are some of the main vegetation types in China. Specifically, the Fagus–Cyclobalanopsis mixed forest is a dominant forest community in themountainous region of Shennongjia. Using three datasets (2001, 2006, and 2010 from a permanent 120 m ×80 m plot in the montane evergreen and deciduous broad-leaved mixed forest in Shengnongjia, we analyzedthe dynamics of tree species composition and community structure for individual trees (DBH ≥ 4 cm. We found that total species number increased from 81 in 2001 to 84 in 2006, and then decreased to 83 in 2010. Dominant species remained constant throughout the study period, including Cyclobalanopsis multiervis, Fagus engleriana, Rhododendron hypoglaucum and Lithocarpus henryi. Stem number and basal area followed the same trend with an initial increase, followed by a decline. The mortality and recruitment of this survey plot changed substantially over the nine-year study period. Although an ice storm in 2008 had some impact on the community, the species richness and community structure did not alter significantly and the community appeared to be in a state of dynamic equilibrium with strong resilience to external disturbances.

  20. Characterization of the Montane Huntington Wildlife Forest Ecosystem Using Machine Learning Approaches from Remote Sensing Data

    Science.gov (United States)

    Li, Manqi

    Montane forests are susceptible to various stressors such as land use and climate change. Consequently, research on characterizing montane forest ecosystems should be conducted on a continuous basis for sustainable forest management. In this research, forest type mapping and change analysis, and biomass/carbon stock quantification were performed over a mountainous forest located in the central Adirondack Park, NY, by employing machine learning techniques at the plot level. Multi-temporal Landsat TM data were used to classify forest type cover and to detect forest cover changes for the past 20 years. Forest biomass and carbon stock quantification was then performed using full waveform LiDAR data collected in September 2011. Accuracies from the two case studies were in support of the versatility of machine learning approaches for forest and ecological investigation. Topographic characteristics affected the classification accuracy as well as the forest type change for the past 20 years. LiDAR-derived metrics, especially height-based ones, proved useful for quantifying biomass/carbon stock. Keywords: Landsat TM, full waveform LiDAR, forest classification, forest change analysis, biomass, carbon stock, machine learning

  1. Montane flora of the southern Langeberg, South Africa: a checklist of the flowering plants and ferns

    Directory of Open Access Journals (Sweden)

    D. J. Mcdonald

    1999-12-01

    Full Text Available The flora of the southern Langeberg is rich, w ith 1 228 species and intraspecific taxa (referred to collectively as species recorded in 361 genera and 105 families. An analysis of the montane flora of the southern Langeberg. Western Cape, South Africa based on an annotated checklist shows that the Asteraceae has the highest number of species per familv (167 and the genus  Erica has the most infrageneric taxa per genus (130 as well as the most endemic species (51. One endemic monotypic family, the Geissolomataceae, two endemic genera Geissoloma and Langebergia (Asteraceae and a total of 167 endemic species are found on the southern Langeberg The plant families of the southern Langeberg flora are ranked according to species-richness of the families and compared with floras of other areas (mainly montane in the Fynbos Biome and marginally to the east of this biome (the Amatole Mountains. The greatest similarity of ranking is evident betw een the plant families of the southern Langeberg and those of the Cape Hangklip Area.

  2. 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.

  3. Zooplankton assemblages in montane lakes and ponds of Mount Rainier National Park, Washington State, USA

    Science.gov (United States)

    Larson, G.L.; Hoffman, R.; McIntire, C.D.; Lienkaemper, G.; Samora, B.

    2009-01-01

    Water quality and zooplankton samples were collected during the ice-free periods between 1988 and 2005 from 103 oligotrophic montane lakes and ponds located in low forest to alpine vegetation zones in Mount Rainier National Park, Washington State, USA. Collectively, 45 rotifer and 44 crustacean taxa were identified. Most of the numerically dominant taxa appeared to have wide niche breadths. The average number of taxa per lake decreased with elevation and generally increased as maximum lake depths increased (especially for rotifers). With one exception, fish presence/absence did not explain the taxonomic compositions of crustacean zooplankton assemblages. Many rotifer species were common members of zooplankton assemblages in montane lakes and ponds in western North America, whereas the crustacean taxa were common to some areas of the west, but not others. Constraints of the environmental variables did not appear to provide strong gradients to separate the distributions of most zooplankton species. This suggests that interspecific competitive interactions and stochastic processes regulate the taxonomic structures of the zooplankton assemblages at the landscape level. Crustacean species that had broad niche breadths were associated with different rotifer taxa across the environmental gradients. Studies of zooplankton assemblages need to address both crustacean and rotifer taxa, not one or the other.

  4. Reproduction and morphology of the common lizard (Zootoca vivipara) from montane populations in Slovakia.

    Science.gov (United States)

    Horváthová, Terézia; Baláž, Michal; Jandzik, David

    2013-02-01

    The common lizard, Zootoca vivipara (Lichtenstein, 1823), shows high variation in life histories and morphology across its range, which comprises almost the entire Palearctic region. However, this variation is not congruent with the species phylogeny. This suggests an important role of the environment in shaping the variation in morphology and life histories of this species. As most data on life histories originate from only a small number of populations and do not cover the species' geographic range and phylogenetic diversity, to fill a gap and provide more information for future comparative studies we investigated reproduction and morphology in two montane populations from Slovakia, central Europe. This region is characterized by taxonomic and phylogenetic diversity and both montane and lowland ecological forms of the common lizard occur here. The common lizards from the Slovak populations are sexually dimorphic, with females having larger body and abdomen lengths and males having larger heads and longer legs. Female common lizards start to reproduce at a relatively large size compared to most other populations. This is consistent with a relatively short activity season, which has been shown to be the main factor driving variation in body size in the common lizard. Clutch size was also relatively high and positively correlated with body size, abdomen size and head size. One third of all females attaining the size of the smallest gravid female showed no signs of reproductive activity despite mating opportunities, suggesting that not all females reproduce annually in this population.

  5. Changes in plant biomass and species composition of alpine Kobresia meadows along altitudinal gradient on the Qinghai-Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Alpine Kobresia meadows are major vegetation types on the Qinghai-Tibetan Plateau. There is growing concern over their relationships among biodiversity, productivity and environments. Despite the im-portance of species composition, species richness, the type of different growth forms, and plant bio-mass structure for Kobresia meadow ecosystems, few studies have been focused on the relationship between biomass and environmental gradient in the Kobresia meadow plant communities, particularly in relation to soil moisture and edaphic gradients. We measured the plant species composition, her-baceous litter, aboveground and belowground biomass in three Kobresia meadow plant communities in Haibei Alpine Meadow Ecosystem Research Station from 2001 to 2004. Community differences in plant species composition were reflected in biomass distribution. The total biomass showed a de-crease from 13196.96±719.69 g/m2 in the sedge-dominated K. tibetica swamp to 2869.58±147.52 g/m2 in the forb and sedge dominated K. pygmaea meadow, and to 2153.08±141.95 g/m2 in the forbs and grasses dominated K. humilis along with the increase of altitude. The vertical distribution of below-ground biomass is distinct in the three meadow communities, and the belowground biomass at the depth of 0-10 cm in K. tibetica swamp meadow was significantly higher than that in K. humilis and K. pygmaea meadows (P<0.01). The herbaceous litter in K. tibetica swamp was significantly higher than those in K. pygnaeca and K. humilis meadows. The effects of plant litter are enhanced when ground water and soil moisture levels are raised. The relative importance of litter and vegetation may vary with soil water availability. In the K. tibetica swamp, total biomass was negatively correlated to species richness (P<0.05); aboveground biomass was positively correlated to soil organic matter, soil moisture, and plant cover (P<0.05); belowground biomass was positively correlated with soil moisture (P<0.05). However, in the K

  6. Changes in plant biomass and species composition of alpine Kobresia meadows along altitudinal gradient on the Qinghai-Tibetan Plateau

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Alpine Kobresia meadows are major vegetation types on the Qinghai-Tibetan Plateau. There is growing concern over their relationships among biodiversity, productivity and environments. Despite the importance of species composition, species richness, the type of different growth forms, and plant biomass structure for Kobresia meadow ecosystems, few studies have been focused on the relationship between biomass and environmental gradient in the Kobresia meadow plant communities, particularly in relation to soil moisture and edaphic gradients. We measured the plant species composition, herbaceous litter, aboveground and belowground biomass in three Kobresia meadow plant communities in Haibei Alpine Meadow Ecosystem Research Station from 2001 to 2004. Community differences in plant species composition were reflected in biomass distribution. The total biomass showed a decrease from 13196.96±719.69 g/m2 in the sedge-dominated K. tibetica swamp to 2869.58±147.52 g/m2 in the forb and sedge dominated K. pygmaea meadow, and to 2153.08±141.95 g/m2 in the forbs and grasses dominated K. humilis along with the increase of altitude. The vertical distribution of belowground biomass is distinct in the three meadow communities, and the belowground biomass at the depth of 0-10 cm in K. tibetica swamp meadow was significantly higher than that in K. humilis and K. pygmaea meadows (P<0.01). The herbaceous litter in K. tibetica swamp was significantly higher than those in K. pygnaeca and K. humilis meadows. The effects of plant litter are enhanced when ground water and soil moisture levels are raised. The relative importance of litter and vegetation may vary with soil water availability. In the K. tibetica swamp, total biomass was negatively correlated to species richness (P<0.05); aboveground biomass was positively correlated to soil organic matter, soil moisture, and plant cover (P<0.05); belowground biomass was positively correlated with soil moisture (P<0.05). However, in

  7. 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...

  8. 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...

  9. Diversity and distribution of the bryophyte flora in montane forests in the Chapada Diamantina region of Brazil

    Directory of Open Access Journals (Sweden)

    Emilia de Brito Valente

    2013-09-01

    Full Text Available Bryophytes constitute an important component of tropical rain forests, which provide microhabitats favorable for their establishment. Bryophytes are also quite responsive to changes in microclimate, which makes them good bioindicators. This study aimed to determine the diversity and distribution of bryophytes in upper and lower montane forests of the Chapada Diamantina region of the state of Bahia, Brazil. To that end, we studied community aspects such as richness, diversity, substrates colonized, life forms and floristic similarity between areas and regions. In 2007 and 2008, we collected specimens from six forest sites, located from the north to the south of the Chapada Diamantina region. We identified a total of 205 infrageneric taxa. In comparison with the lower montane forests, the upper montane forests presented higher diversity and species richness, as well as greater numbers of substrates colonized, life form types, species of restricted geographic distribution and species typical of shaded areas. We also found low similarity in the species composition, the populations of the upper and lower montane forests forming two large and distinct groups. Although presenting relatively high floristic homogeneity among themselves, the Chapada Diamantina areas presented little similarity with those of the Atlantic Forest. This can be explained by the differences between the two regions in terms of environmental conditions, precipitation, seasonality, elevation and continentality.

  10. 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 b

  11. 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 a

  12. Root nodulation in the wetland tree Pterocarpus officinalis along coastal and montane systems of Northeast of Puerto Rico

    Science.gov (United States)

    Rachel Pérez; Tamara Heartsill Scalley

    2008-01-01

    In Puerto Rico, brackish water wetlands were dominated by Pterocarpus officinalis previous to extensive deforestation due to agriculture. Today remnant wetlands are limited to small areas that are threatened by rise in sea level. We examined the root nodules of P. officinalis in montane and coastal sites and at 0, 10, 20 cm from the surface to determine if site...

  13. Wormmos (Pseudocalliergon trifarium) in trilveen in De Wieden: een arctisch-boreaal-montane mossoort, nieuw voor de Benelux

    NARCIS (Netherlands)

    Weeda, E.J.

    2006-01-01

    Zeer goed onderzochte gebieden blijven verrassingen bieden. Zo is Noordwest- Overijssel is bryologisch grondig onderzocht. Toch kon hier op 20 juni 2006 een nieuwe mossoort voor de Nederlandse flora worden buitgemaakt, en nog wel één met een arctisch-boreaal-montane verspreiding

  14. 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...

  15. 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...

  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. 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

  18. Atmospheric organic and inorganic nitrogen inputs to coastal urban and montane Atlantic Forest sites in southeastern Brazil

    Science.gov (United States)

    de Souza, Patricia A.; Ponette-González, Alexandra G.; de Mello, William Z.; Weathers, Kathleen C.; Santos, Isimar A.

    2015-06-01

    Tropical regions are currently experiencing changes in the quantity and form of nitrogen (N) deposition as a result of urban and industrial emissions. We quantified atmospheric N inputs to two coastal urban and two montane (400 m and 1000 m) Atlantic Forest sites downwind of the Metropolitan Region of Rio de Janeiro (MRRJ), Brazil, from August 2008 to August 2009. Concentrations of total dissolved nitrogen (TDN), dissolved inorganic nitrogen (DIN) and urea were measured in bulk precipitation at all sites, as well as in canopy throughfall in the lower montane forest. Dissolved organic nitrogen (DON) was calculated as the difference between TDN and DIN (NH4+ + NO3- + NO2-). Annual volume-weighted mean bulk concentrations of all N species were higher at the coastal urban than montane forest sites, with DON accounting for 32-56% and 26-32%, respectively, of the TDN concentration in bulk precipitation. Bulk deposition of TDN ranged 12.1-17.2 kg N ha- 1 yr- 1 and tended to decrease with increasing distance from the coastal urban region. In the lower montane forest, throughfall TDN flux, 34.3 kg N ha- 1 yr- 1, was over 2-fold higher than bulk TDN deposition, and DON comprised 57% of the total N deposited by throughfall to the forest soil. Urea comprised 27% of DON in throughfall compared to up to 100% in bulk precipitation. Our findings show that DON is an important, yet understudied, component of TDN deposition in tropical forest regions, comprising one-third to greater than one-half of the N deposited in rainfall and throughfall. Further, in this lower montane Atlantic Forest site, throughfall DIN flux was 1.5-3 fold higher than the suggested empirical critical load for humid tropical forests, highlighting the potential for increasing N pollution emitted from the MRRJ to impact N cycling in adjacent ecosystems.

  19. Spatially explicit feedbacks between seagrass meadows, sediment, and light: habitat suitability for seagrass growth

    Science.gov (United States)

    Carr, J. A.; D'Odorico, P.; McGlathery, K.; Wiberg, P. L.

    2011-12-01

    In shallow costal bays in which 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. When sediment resuspension is high, resultant low light environments can limit benthic primary productivity. However, both currents and waves are affected by the presence of benthic plants such as seagrass. Moreover, vegetated areas influence a larger area than they footprint, including an adjacent downstream area. This region, while barren of seagrass, exhibits reduced shear stresses until boundary layer reformation occurs. We develop a simplistic approach to explore how the patchy structure of seagrass meadows may affect sediment resuspension and the consequent light environment under tidal and wind-wave forcing due to the presence of this sheltered region. In order to investigate the effect of patch modified hydrodynamics we generated heterogeneous vegetation covers comprised of a mosaic of randomly distributed patches with exponentially distributed radii. These heterogenous landscapes were generated from two perspectives. First, circular patches were randomly placed on a bare landscape; with each circular patch assumed to be a seagrass meadow. Second, starting from a landscape assumed to be homogenous meadow with constant shoot density, circular gaps were randomly generated. Each gap was considered a disturbance that completely removed all seagrass from within the circular region. Fractional cover of vegetation on the landscape was used to facilitate comparisons across landscape realizations and perspectives. Each landscape realization was then used to partition wave and current shear stresses on the landscape. Total suspended sediment and light attenuation characteristics were then calculated and averaged over the landscape to examine how both fractional cover and mean water depth affect the bulk sediment and light environment from the meadow or gap

  20. Artificial Management Improves Soil Moisture, C, N and P in an Alpine Sandy Meadow of Western China

    Institute of Scientific and Technical Information of China (English)

    WU Gao-Lin; LI Wei; ZHAO Ling-Ping; SHI Zhi-Hua

    2011-01-01

    Regeneration of degraded grassland ecosystems is a significant issue in restoration ecology globally.To understand the effects of artificial management measures on alpine meadows, we surveyed topsoil properties including moisture, organic carbon (SOC), nitrogen (N), and phosphorus (P) contents five years after fencing and fencing + reseeding management practices in a sandy meadow in the eastern Qinghai-Tibetan Plateau, northwestern China.Both the fencing and fencing + reseeding management practices significantly increased soil moisture storage, SOC, total N, available N, total P, and available P, as compared to the unmanaged control.Fencing plus reseeding was more effective than fencing alone for improving soil C, N, and P contents.These suggested that rehabilitation by reseeding and fencing generally had favorable effects on the soil properties in degraded sandy alpine meadows, and was an effective approach for restoration of degraded meadow ecosystems of the Qinghai-Tibetan Plateau.

  1. Sunkhaze Meadows National Wildlife Refuge, Carlton Pond National Wildlife Refuge: Annual narrative report: January 1, 1997 to September 30, 1997

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual narrative report for Sunhaze Meadows NWR and Carlton Pond WPA outlines activities and accomplishments between January and September of 1997. The report...

  2. Influences of the degradation of swamp and alpine meadows on CO2 emission during growing season on the Qinghai-Tibet Plateau

    Institute of Scientific and Technical Information of China (English)

    WANG JunFeng; WANG GenXu; WANG YiBo; LI YuanShou

    2007-01-01

    CO2 emission fluxes of two types of ecosystem, swamp meadow and alpine meadow, in the Fenghuo- shan region of the Qinghai-Tibet Plateau were studied by the static chamber-portable infrared chromatographic method. The results showed that there was large difference in the CO2 emission fluxes between the two ecosystems and in the same ecosystem of different degradation degrees. CO2 emission flux of the swamp meadow gradually decreased with increasing degradation degree, while that of the alpine meadow gradually increased with increasing degradation degree except in May. The CO2 emission flux of undegraded swamp meadow was 65.1%―80.3% higher than that of undegraded alpine meadow; and the CO2 emission flux of moderately degraded swamp meadow was 22.1%―67.5% higher than that of alpine meadow; but the CO2 emission flux of severely degraded alpine meadow was 14.3%―29.5% higher than that of swamp meadow. The soil moisture content and temperature in the upper 5 cm soil layer and above-ground biomass were significantly correlated with the CO2 emission fluxes and regarded as the main environment factors to control the CO2 emission.

  3. 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

  4. 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

  5. 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.

  6. 常压逆流连续萃取褐煤蜡工艺初探%Tentative exploration about Atmospheric Pressure Countercurrent Continuous Extracting Montan Wax Process

    Institute of Scientific and Technical Information of China (English)

    崔东方

    2013-01-01

    概述了褐煤蜡的特性和应用,重点介绍了褐煤蜡连续萃取的工艺流程,旨在推动我国褐煤蜡产业的发展,期望我国褐煤蜡能够大规模生产,从而大幅度提高劳动生产率,提高市场竞争力。%This article summarizes features and applications of Montan Wax, and highlights process of continuous extraction of Montan Wax so as to promote development of Montan Wax industry in our country, at the same time, we also expect large-scale production of Montan Wax, so that increase productivity greatly and improve market competitiveness.

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

    DEFF Research Database (Denmark)

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

    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...... 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...

  8. 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

    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...... 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...

  9. Wild red deer (Cervus elaphus L. grazing may seriously reduce forage production in mountain meadows

    Directory of Open Access Journals (Sweden)

    Maurizio Ramanzin

    2012-01-01

    Full Text Available This study aimed at estimating the impact of red deer grazing on the productivity of meadows located in Pian Cansiglio, north-eastern Italian Pre-Alps. These meadows (383 ha; average elevation 1000 m asl are managed for hay/silage production (1-2 cuts per season and are included in a protected area that hosts a high density of deer (around 30 heads/100 ha. In 2008 and 2010, dry matter (DM production and loss due to deer grazing were estimated with exclusion cages (1 m2; 48 exclusion cages in 2008 and 52 in 2010. Night counts with spotlights were conducted to index deer use of meadows plots. DM production inside the cages was fairly good for the area (first and second cut: 5079 - 2193 Kg DM/ha in 2008, and 4200 - 2615 Kg DM/ha in 2010. DM production outside the cages was significantly lower (first and second cut in 2008: 4314-1389 Kg DM/ha, and in 2010: 3376-2052 Kg DM/ha. Therefore, the magnitude of losses was of 15-20% in the first and 25-40% in the second cut. DM losses in the different meadow plots were positively correlated with index of deer use, which in some plots was as high as 7-8 heads/ha. Deer grazing reduced also crude protein (CP content of forage (15.6±4.4% DM inside exclusion cages and 13.8±3.5% DM outside, with losses being greater where CP content was higher. This study demonstrates that high densities of grazing deer may seriously impact on forage production and quality.

  10. Endophytic fungus decreases plant virus infections in meadow ryegrass (Lolium pratense)

    OpenAIRE

    Lehtonen, Päivi T; Helander, Marjo; Shahid A Siddiqui; Lehto, Kirsi; Saikkonen, Kari

    2006-01-01

    We studied the effects of fungal endophyte infection of meadow ryegrass (Lolium pratense=Festuca pratensis) on the frequency of the barley yellow dwarf virus (BYDV). The virus is transferred by aphids, which may be deterred by endophyte-origin alkaloids within the plant. In our experiment, we released viruliferous aphid vectors on endophyte-infected and endophyte-free plants in a common garden. The number of aphids and the percentage of BYDV infections were lower in endophyte-infected plants ...

  11. Assessment and physiological state of the Posidonia oceanica meadows in Porto Cristo (Manacor, Spain)

    Science.gov (United States)

    Sureda, Antoni; Box, Antonio; Tejada, Silvia

    2015-12-01

    In the Mediterranean Sea, Posidonia oceanica is the main seagrass meadow that brings food and shelter to many species. The P. oceanica deterioration is an indicator of its own status, since it is sensitive to many disturbances, such as human impacts or alien species. Lately, oxidative stress has been pointed out as another possible biomarker of the animal and plant status. The aim of this work was to evaluate the physiological status of the P. oceanica meadows in the Porto Cristo bay (Manacor, Mallorca, Balearic Islands, Western Mediterranean), evaluating the possible impact induced by human activity performed in the area. In situ measurements were quantified (shoot density, and the maximum length and width of P. oceanica leaves) by scuba divers. Leaf samples were collected to determine the catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities. The malondialdehyde (MDA) level as marker of lipid peroxidation was also evaluated. Shoot density, and length and width measurements of the leaves in the inner locations of the bay showed inferior structural features than the leaves from the outer areas. CAT, SOD and GPx enzymatic activities and lipid peroxidation were higher in leaves from the internal zones than in the outer placements. In conclusion, the general status of the of P. oceanica meadows on the Porto Cristo Bay according to structural and oxidative biomarkers evidenced a good physiological condition, although the areas nearest to the harbour and the beach reflect signs of human affection. Altogether, it reflects a good physiological condition of the meadows in the external areas of the Porto Cristo Bay.

  12. Meadow birds on organic and conventional arable farms in the Netherlands: abundance and nest success

    OpenAIRE

    Kragten, Steven

    2010-01-01

    Intensification of agriculture is mentioned to be the key drive behind the decline of farmland birds on grassland and on arable land. This raises the question whether a less intensive system, such as organic, can stop or reverse these declines. The present study compares (1) the territory densities of meadow birds on organic and conventional arable farms, and (2) the nesting success of Lapwings (Vanellus vanellus) on both farm types. The study was carried out in Oostelijk Flevoland and Noordo...

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

    OpenAIRE

    Janicka Maria; Pawluśkiewicz Bogumiła; Małuszyńska Elżbieta; Szydłowska Anna

    2016-01-01

    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 diaspor...

  14. Long-term effect of beach replenishment on natural recovery of shallow Posidonia oceanica meadows

    Science.gov (United States)

    González-Correa, José M.; Torquemada, Yolanda Fernández; Sánchez Lizaso, José Luis

    2008-03-01

    The recovery capacity of shallow Posidonia oceanica meadows degraded by beach replenishment eighteen years before was assessed in two impacted meadows and compared with other two undisturbed localities. Inside each locality, we selected randomly three sites separated by 500-1000 m. At site level we study the vitality of P. oceanica meadow assessing the vegetative growth, leaf characteristics, and non-structural carbohydrates of the plants. Additionally, at locality level, silt-clay fraction, organic matter, pH and light intensity incident on the sea bottom were measured to evaluate the environmental conditions. Covering of P. oceanica was significantly lower at the impacted localities while amount of dead "matte" was higher. Leaf production of horizontal rhizomes (14.6 ± 1.11 vs 19.47 ± 1.45 leaves y -1), net total rhizomes recruitment (2.33 ± 0.17 vs 4.3 ± 0.33 branches y -1) and starch concentration (43.625 ± 0.67 vs 54.45 ± 0.74 mg per g of rhizome) at impacted meadows were significantly lower than controls. Leaf features, epiphytes biomass, colonization, elongation and horizontal and vertical rhizome production did not show significant differences. Sediments at impacted localities contained higher silt-clay fraction and higher organic matter load while pH was lower. Light intensity on the sea bottom measured at all localities was over the minimum light requirements estimated for P. oceanica. Our results show that the press impact produced by beach replenishment was enduring in the time slowing natural recovery by 45%. This impact may be related with changes in the sediment features.

  15. 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...... to elevational gradients in climate has been emphasized as a driver of vegetation distribution and plant community assembly in tropical mountain areas such as the Andes for two centuries, while alternative mechanisms have been little studied. Here, we investigated the importance of topography and spatial......). 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...

  16. Taraxacum officinale pollen depresses seed set of montane wildflowers through pollen allelopathy

    Directory of Open Access Journals (Sweden)

    Deirdre Loughnan

    2014-08-01

    Full Text Available Plant species that share pollinators can suffer from interspecific pollen deposition. Male reproductive success is inevitably reduced by the loss of pollen to flowers of another species. Female reproductive success can be affected by reduced stigmatic area or, more strongly, through allelopathic effects by which the admixture of some foreign pollen reduces seed or fruit set. We tested for allelopathic effects of Taraxacum officinale (Asteracaeae pollen on the seed set of montane wildflowers Erythronium grandiflorum (Liliaceae and Erysimum capitatum (Brassicaceae, by hand-pollinating plants with pollen mixtures. Taraxacum is a common invasive species, which produces allelopathic chemicals in its root and vegetative tissue, making it a likely candidate for pollen allelopathy. Flowers of both species produced fewer well-developed seeds when pollinated with pollen mixtures containing Taraxacum pollen. The pollen-allelopathic potential of weedy dandelion may add to its ability to disrupt communities that it invades.

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

    Directory of Open Access Journals (Sweden)

    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.

  18. 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.

  19. Postdispersal removal and germination of seed dispersed by Cercopithecus nictitans in a West African Montane Forest.

    Science.gov (United States)

    Chapman, Hazel M; Goldson, Stephen L; Beck, Josie

    2010-01-01

    Factors that determine the effectiveness of primates as seed dispersers include (i) the microsite into which they deposit seed, (ii) secondary removal of seed by other taxa and (iii) the effect of gut passage and/or spitting on subsequent seed germination. This contribution evaluated these factors in the little studied putty-nosed monkey, Cercopithecus nictitans, in a Nigerian montane forest. Field experiments showed that C. nictitans has greatly increased in its importance as a disperser of medium-sized seed (>5 mm) because other large primates have been hunted to near extinction. C. nictitans disperses seed across habitats by spitting and defaecation. Rates of secondary seed removal were high for all seed species irrespective of the presence or absence of C. nictitans faecal matter, size or microsite variables. Gut passage enhanced germination relative to hand-cleaned seed, while spitting had either no effect or decreased the germination rate. Copyright 2010 S. Karger AG, Basel.

  20. 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.

  1. Application of UAS photogrammetry for assessment of flood driven fluvial dynamics of montane stream. Case study - Roklansky creek, Sumava Mts.

    Science.gov (United States)

    Langhammer, Jakub; Miřijovský, Jakub; Hartvich, Filip; Kaiglová, Jana

    2014-05-01

    Current progress in hydrology and fluvial geomorphology is largely based on new field survey and analysis techniques, employing advanced technologies for monitoring the dynamics of the runoff process, field surveying and for remote monitoring of changes in riverbeds and of fluvial dynamics. Application of these techniques allows researchers to obtain information on a significantly higher qualitative level than using traditional methods of field survey and measurement, either in terms of spatial accuracy and resolution, frequency of sampling or qualitative characteristics of acquired data. The contribution demonstrates the potential of Unmanned Aerial Systems (UAS) for analysis of fluvial dynamics of montane stream, driven by flood in combination with other survey techniques, namely the ground LiDAR scanning, digital granulometry and automated water level monitoring. The UAS photogrammetry is employed in the study to acquire high precision DTMs, enabling reconstruction of riverbed and quantitative analysis of volumetric changes related to initial flood events. The hexacopter UAS platform has been used to acquire the data for photogrammetric analysis of complex stretch of stream with historically elevated fluvial dynamics. The photogrammetric reconstruction enabled to build accurate DTM of riverbed and floodplain before and after the initial event and to calculate the extent of volumetric changes. The potential of UAS photogrammetry for fluvio morphological study is in combination with other monitoring and survey techniques, enabling complex analysis of fluvial dynamics. The magnitude, duration and hydrological properties of initial flood event were derived from automated high frequency water level monitoring. The digital granulometry enabled to analyze the structure of sedimentary material in floodplain. The terrestrial LiDAR scanning allows construction of very detailed 3D models of selected fluvial forms, enabling deeper insight into the effects of fluvial

  2. Invasion of Gleditsia triacanthos in Lithraea ternifolia Montane Forests of Central Argentina.

    Science.gov (United States)

    Marco; Páez

    2000-10-01

    / The aim of this work is to study the invasion system constituted by the alien species Gleditsia triacanthos and the native dominant Lithraea ternifolia in montane forests of central Argentina, considering life history and demographic traits of both the alien and the native species and different site conditions for population growth (good and bad sites). Matrix models are applied to project the consequences of differences in vital rates for population growth. Analyzing these models helps identify which life cycle transitions contributed most to population growth. Obtained population growth rates are considered to assess predicted rates of spread using the reaction-diffusion (R-D) model. G. triacanthos presents many of the life history traits that confer plants high potential for invasiveness: fast growth, clonal and sexual reproduction, short juvenile period, high seed production, and high seed germinability. These traits would ensure G. triacanthos invasive success and the displacement of the slow-growing, relatively less fecund native L. ternifolia. However, since disturbance and environmental heterogeneity complicate the invasibility pattern of G. triacanthos in these montane forests, the outcome of the invasion process is not straightforward as could be if only life history traits were considered.Great variation in demographic parameters was observed between populations of each species at good and bad sites. Though both good and bad sites signified increasing or at least stable populations for G. triacanthos, for L. ternifolia bad sites represented local extinction. Analyzing the results of matrices models helps design the optimal management for the conservation of L. ternifolia populations while preventing the invasion by G. triacanthos. The predicted asymptotic rate of spread for G. triacanthos at the good site was fourfold greater than the predicted one for L. ternifolia, although the difference was much smaller considering the bad site. The usefulness of

  3. 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.

  4. DNA Barcoding of an Assembly of Montane Andean Butterflies (Satyrinae): Geographical Scale and Identification Performance.

    Science.gov (United States)

    Marín, M A; Cadavid, I C; Valdés, L; Álvarez, C F; Uribe, S I; Vila, R; Pyrcz, T W

    2017-01-23

    DNA barcoding is a technique used primarily for the documentation and identification of biological diversity based on mitochondrial DNA sequences. Butterflies have received particular attention in DNA barcoding studies, although varied performance may be obtained due to different scales of geographic sampling and speciation processes in various groups. The montane Andean Satyrinae constitutes a challenging study group for taxonomy. The group displays high richness, with more of 550 species, and remarkable morphological similarity among taxa, which renders their identification difficult. In the present study, we evaluated the effectiveness of DNA barcodes in the identification of montane Andean satyrines and the effect of increased geographical scale of sampling on identification performance. Mitochondrial sequences were obtained from 104 specimens of 39 species and 16 genera, collected in a forest remnant in the northwest Andes. DNA barcoding has proved to be a useful tool for the identification of the specimens, with a well-defined gap and producing clusters with unambiguous identifications for all the morphospecies in the study area. The expansion of the geographical scale with published data increased genetic distances within species and reduced those among species, but did not generally reduce the success of specimen identification. Only in Forsterinaria rustica (Butler, 1868), a taxon with high intraspecific variation, the barcode gap was lost and low support for monophyly was obtained. Likewise, expanded sampling resulted in a substantial increase in the intraspecific distance in Morpho sulkowskyi (Kollar, 1850); Panyapedaliodes drymaea (Hewitson, 1858); Lymanopoda obsoleta (Westwood, 1851); and Lymanopoda labda Hewitson, 1861; but for these species, the barcode gap was maintained. These divergent lineages are nonetheless worth a detailed study of external and genitalic morphology variation, as well as ecological features, in order to determine the potential

  5. Demographic responses of boreal-montane orchid Malaxis monophyllos (L. Sw. populations to contrasting environmental conditions

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    Edyta Jermakowicz

    2016-03-01

    Full Text Available In an age of changes in species’ geographical ranges, compounded by climatic and anthropogenic impacts, it become important to know which processes and factors influence plant populations and their persistence in the long term. Here we investigated dynamic and fitness components in twelve populations of Malaxis monophyllos (L. Sw., situated in different geographical (regions and ecological (type of habitat units. Although M. monophyllos is a rare species, characterized by highly fragmented, boreal-montane distribution range, in last few decades it successfully colonized secondary habitats in Polish uplands. Our results indicate that M. monophyllos is represented mainly by small populations, which annual spatial and temporal changes might be very high, what affects the ephemeral character of these populations, regardless of the region and type of habitat. This dynamic structure, in turn, is caused by intensive exchange of individuals in populations, as well as by their short above-ground life span. Despite the large range of variation in size and reproductive traits, we can distinguish some regional patterns, which indicate boreal region as the most optimal for M. monophyllos growth and persistence in the long term, and with montane and upland/anthropogenic populations, due to lower reproductive parameters, as the most threatened. Although it should be considered that anthropogenic populations, despite their lower reproductive parameters and instability in the long term, present an intermediate, geographical and ecological character, therefore they may be valuable in shaping, both M. monophyllos’ future range, as well as its potential for response on ongoing and future changes. In general, reproduction is the main factor differentiating of M. monophyllos populations in regions, and we can suspect that it may become the cause of the future differentiation and isolation of these populations, occurring with progressive range fragmentation.

  6. 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.

  7. Subspecific Differentiation Events of Montane Stag Beetles (Coleoptera, Lucanidae) Endemic to Formosa Island.

    Science.gov (United States)

    Tsai, Cheng-Lung; Yeh, Wen-Bin

    2016-01-01

    Taxonomic debates have been carrying on for decades over Formosan stag beetles, which consist of a high proportion of endemic species and subspecies featuring morphological variations associated with local adaptation. With the influence of periodical Pleistocene glaciations and the presence of several mountain ranges, the genetic differentiation and taxonomic recognition, within this medium-size island, of two endemic subspecies for each of four montane stag beetles, i.e. Lucanus ogakii, L. kanoi, Prismognathus davidis, and Neolucanus doro, has been an appealing issue. Based on monophyletic lineages and population structure, possible divergent scenarios have been proposed to clarify the subspecific status for each of the above mentioned stag beetles. Phylogenetic inferences based on COI+16S rDNA+28S rDNA of 240 Formosan lucanids have confirmed most species are monophyletic groups; and the intraspecific (2%) genetic distances of the two mitochondrial genes could be applied concordantly for taxonomic identification. On account of Bayesian-based species delimitation, geographic distribution, population structure, and sequence divergences, the subspecific status for L. ogakii, L. kanoi, and Pri. davidis are congruent with their geographic distribution in this island; and the calibration time based on the mitochondrial genes shows the subspecific split events occurred 0.7-1 million years ago. In addition, a more complicated scenario, i.e. genetic differentiation including introgression/hybridization events, might have occurred among L. ogakii, L. kanoi, and L. maculifemoratus. The geological effects of mountain hindrance accompanied by periodical glaciations could have been vital in leading to the geographical subspecific differentiation of these montane stag beetles.

  8. 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.

  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. 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.

  11. Diversity and persistence of arbuscular mycorrhizas in a low-Arctic meadow habitat.

    Science.gov (United States)

    Pietikäinen, Anne; Kytöviita, Minna-Maarit; Husband, Rebecca; Young, J Peter W

    2007-01-01

    Little is known about the ecology and diversity of arbuscular mycorrhizal (AM) fungi in Arctic ecosystems. Here, the diversity and composition of the AM fungal community and its response to host plant community composition were studied in a low-Arctic meadow habitat. The natural vegetation in two low-Arctic meadow sites was manipulated. Plots with natural vegetation, monoculture and no vegetation were established. Seeds of Solidago virgaurea were sown into the plots and the AM fungal community in the seedling roots was analysed using the terminal restriction fragment length polymorphism (T-RFLP) method. The vegetation manipulation treatments affected the community composition but not the diversity of AM fungi found in S. virgaurea roots. The diversity of AM fungi was higher in S. virgaurea roots in the site with naturally higher plant species diversity. These results show that AM fungi in low-Arctic meadows are able to survive for a period of 2 yr without a host plant. This ability buffers the AM fungal community against short-term changes in host plant community composition and diversity.

  12. Meadow fragmentation and reproductive output of the SE Asian seagrass Enhalus acoroides [rapid communication

    Science.gov (United States)

    Vermaat, Jan E.; Rollon, Rene N.; Lacap, Cristina Day A.; Billot, Claire; Alberto, Filipe; Nacorda, Hildie M. E.; Wiegman, Frank; Terrados, Jorge

    2004-11-01

    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 of the seagrass meadow was quantified as cover of E. acoroides and all seagrass species present in 20×20 m plots. E. acoroides and overall seagrass cover were correlated positively. The proportion of female flowers of E. acoroides that developed a fruit increased sharply as overall seagrass cover was around 50%. Apparent sex ratio bore no relationship with overall seagrass cover. This threshold-type of relationship suggests that fragmentation of seagrass meadows can have a major effect on the reproductive output of this species. A possible mechanism underlying these results would be a non-linear increase of the efficiency of trapping the surface-dispersed pollen with increasing seagrass canopy density. This provides the first evidence based on real data that fragmentation can affect the population dynamics of seagrass species.

  13. Seasonal and inter-annual variations of community metabolism rates of a Posidonia oceanica seagrass meadow

    Science.gov (United States)

    Champenois, W.; Borges, A. V.

    2012-04-01

    We report gross primary production (GPP), community respiration (CR), and net community production (NCP) over Posidonia oceanica meadow at 10 m in Corsica (Bay of Revellata) based on the open water O2 mass balance from a data-set of hourly measurements with an array of three O2 optodes deployed from August 2006 to October 2009. The method was checked by comparison with discrete measurements of metabolic rates derived from benthic chamber incubations also based on the diel change of O2. This comparison was satisfactory and actually highlights the potential caveats of benthic incubation measurements related to O2 accumulation in small chambers leading to photorespiration, and an under-estimation of GPP. Our data confirmed previous P. oceanica meadows GPP and CR values, strong seasonal variations, and net autotrophy. High resolution data revealed strong inter-annual variability, with a decrease of GPP by 35% and NCP by 87% during 2006-2007 characterized by a mild and less stormy winter compared 2007-2008 and 2008-2009. P. oceanica meadows are then expected to decrease export of organic carbon to adjacent communities (decrease of NCP), since a decrease in frequency and intensity of marine storms is expected in future in the Mediterranean Sea, due to a northward shift of the Atlantic storm track.

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

    Science.gov (United States)

    Unsworth, Richard K F; Rasheed, Michael A; Chartrand, Kathryn M; Roelofs, Anthony J

    2012-01-01

    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.

  15. 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.

  16. Tidal controls on trace gas dynamics in a seagrass meadow of the Ria Formosa lagoon (southern Portugal

    Directory of Open Access Journals (Sweden)

    E. Bahlmann

    2014-07-01

    Full Text Available Coastal zones are important source regions for a variety of trace gases including halocarbons and sulphur-bearing species. While salt-marshes, macroalgae and phytoplankton communities have been intensively studied, little is known about trace gas fluxes in seagrass meadows. Here we report results of a newly developed dynamic flux chamber system that can be deployed in intertidal areas over full tidal cycles allowing for high time resolved measurements. The trace gases measured in this study included carbon dioxide (CO2, methane (CH4 and a variety of hydrocarbons, halocarbons and sulphur-bearing compounds. The high time resolved CO2 and CH4 flux measurements revealed a complex dynamic mediated by tide and light. In contrast to most previous studies our data indicate significantly enhanced fluxes during tidal immersion relative to periods of air exposure. Short emission peaks occured with onset of the feeder current at the sampling site. We suggest an overall strong effect of advective transport processes to explain the elevated fluxes during tidal immersion. Many emission estimates from tidally influenced coastal areas still rely on measurements carried out during low tide only. Hence, our results may have significant implications for budgeting trace gases in coastal areas. This dynamic flux chamber system provides intensive time series data of community respiration (at night and net community production (during the day of shallow coastal systems.

  17. Sulfur cycle in the typical meadow Calamagrostis angustifolia wetland ecosystem in the Sanjiang Plain, Northeast China

    Institute of Scientific and Technical Information of China (English)

    LIU Jingshuang; LI Xinhua

    2008-01-01

    The sulfur cycle and its compartmental distribution within an atmosphere-plant-soil system was studied using a compartment model in the typical meadow Calamagrostis angustifolia wetland in the Sanjiang Plain Northeast China. The results showed that in the typical meadow C. angustifolia wetland ecosystem, soil was the main storage compartment and current hinge of sulfur in which 98.4% sulfur was accumulated, while only 1.6% sulfur was accumulated in the plant compartment. In the plant subsystem, roots and litters were the main storage compartment of sulfur and they remained 83.5% of the total plant sulfur. The calculations of sulfur turnover through the compartments of the typical meadow C. angustifolia wetland ecosystem demonstrated that the above-ground component took up 0.99 gS/m2 from the root, of which 0.16 gS/m2 was translocated to the roots and 0.83 gS/m2 to the litter. The roots took in 1.05 gS/m2 from the soil, subsequent translocation back to the soil accounted for 1.31 gS/m2, while there was 1.84 gS/m2 in the litter and the net transfer of sulfur to the soil was more than 0.44 gS/(m2·a). The emission of H2S from the typical meadow C. angustifolia wetland ecosystem to the atmosphere was 1.83 mgS/(m2·a), while carbonyl sulfide (COS) was absorbed by the typical meadow C. angustifolia wetland ecosystem from the atmosphere at the rate of 1.76 mgS/(m2·a). The input of sulfur by the rainfall to the ecosystem was 4.85 mgS/m2 during the growing season. The difference between input and output was 4.78 mgS/m2, which indicated that sulfur was accumulated in the ecosystem and may cause wetland acidify in the future.

  18. Sulfur cycle in the typical meadow Calamagrostis angustifolia wetland ecosystem in the Sanjiang plain, Northeast China.

    Science.gov (United States)

    Liu, Jingshuang; Li, Xinhua

    2008-01-01

    The sulfur cycle and its compartmental distribution within an atmosphere-plant-soil system was studied using a compartment model in the typical meadow Calamagrostis angustifolia wetland in the Sanjiang Plain Northeast China. The results showed that in the typical meadow C. angustifolia wetland ecosystem, soil was the main storage compartment and current hinge of sulfur in which 98.4% sulfur was accumulated, while only 1.6% sulfur was accumulated in the plant compartment. In the plant subsystem, roots and litters were the main storage compartment of sulfur and they remained 83.5% of the total plant sulfur. The calculations of sulfur turnover through the compartments of the typical meadow C. angustifolia wetland ecosystem demonstrated that the above-ground component took up 0.99 gS/m2 from the root, of which 0.16 gS/m2 was translocated to the roots and 0.83 gS/m2 to the litter. The roots took in 1.05 gS/m2 from the soil, subsequent translocation back to the soil accounted for 1.31 gS/m2, while there was 1.84 gS/m2 in the litter and the net transfer of sulfur to the soil was more than 0.44 gS/(m2 x a). The emission of H2S from the typical meadow C. angustifolia wetland ecosystem to the atmosphere was 1.83 mgS/(m2 x a), while carbonyl sulfide (COS) was absorbed by the typical meadow C. angustifolia wetland ecosystem from the atmosphere at the rate of 1.76 mgS/(m2 x a). The input of sulfur by the rainfall to the ecosystem was 4.85 mgS/m2 during the growing season. The difference between input and output was 4.78 mgS/m2, which indicated that sulfur was accumulated in the ecosystem and may cause wetland acidify in the future.

  19. The role of dew in the monsoon season assessed via stable isotopes in an alpine meadow in Northern Tibet

    Science.gov (United States)

    He, Siyuan; Richards, Keith

    2015-01-01

    Rain in the summer monsoon season is the main water input for the water cycle in the alpine meadow ecosystem of Northern Tibet, however, dew has been observed frequently in Nagqu, especially during consecutive dry days. Under climate change and human disturbance, degradation of the meadow leads to surface property changes and these may affect dew formation. The amount of dew formed on top of the vegetation surface was therefore measured on normal Kobresia pygmaea meadow and partly-degraded crusted meadow soil for 12 dew days in the 40 observation days from early-July to mid-August in 2011. The converted average daily dew depth was significantly higher on the normal meadow and the average of 0.15 mm/night was three times that on the degraded surface between 20:00 and 7:00. To qualitatively identify the role of dew in the local water cycle, water samples from atmospheric water vapour, rain, creek water and groundwater were collected in July and August of 2011 for the analysis of stable water isotopes using the isotope ratio infrared spectroscopy method (IRIS); the vapour samples were collected by cryogenic trapping. It is shown in a δD-δ18O space that the dew contains water that has been terrestrially recycled by evapotranspiration. This research takes an initial step to see the impact of meadow degradation on dew formation, with regard to its formative conditions and moisture source, suggesting that dew may be an active water source for meadow growth and hydrological processes during summer dry spells on the high plateau.

  20. 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.

  1. The Moving Tendency of Holdridge Life Zone with Its Dry and Wet Climate Changes of Gannan Meadow in Recent 40 Years%近40年甘南草原生命地带偏移趋势及干湿变化

    Institute of Scientific and Technical Information of China (English)

    王建兵

    2012-01-01

    . Most of the meadows in Gannan Plateau are distributed in Hezuo, Xiahe, Luqu and Maqu, so 4 places are selected as representative area to study the moving tendency of Holdridge life zone and dry and wet climate changes of Gannan meadow. Based on the meteorological data, the method of Holdridge life zone is used to analyze the moving tendency of Holdridge life zone and the dry and wet climate changes of Gannan meadow during 1971-2010. The results show that life zone of Gannan meadow still belongs to the subal-pine meadow of Tibet Plateau alpine vegetation system. But impacted by the global climate change, the temperature of Gannan meadow increases obviously with the tendency ratio of 0. 44-0. 46℃every decade, meanwhile the bio-temperature has increased by 0. 23-0. 27℃ every decade, too. The variety of precipitation shows a different trend between the northern and southern in Gannan meadow, the moving tendency of Holdridge life zone is diverging from the mean center, and the stability of the Gannan meadow ecosystem is attenuating. The Holdridge REp of Gannan meadow shows an obvious ascending tendency in the rate of 0. 02-0. 03 per decade. After the 1990s, the climate of Gannan meadow shows a warm-drying trend, which is more obvious in the southern of Gannan meadow. The humidity degree of Luqu has changed to humid from the perhumid, and Maqu is in the same transition, too. The most important climatic factor for the Holdridge -REP increasing is the temperature, and then is the precipitation and the air humidity. The temperature rising plays a very important role in the warm-drying trend of Gannan meadow. Considering the complexity of the environment and the fragility of the ecology system in the border area of Tibet Plateau, the impact of this change on ecology and environment of Gannan meadow still needs further study.

  2. 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 < 0.0001). FTIR spectral analysis indicated that higher MoM content under aspen was not due to higher concentration of recalcitrant compounds (e.g., aliphatic and aromatic C), but rather to stabilization of simple molecules (e.g., polysaccharides) of 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

  3. Genetic variation and risks of introgression in the wild Coffea arabica gene pool in south-western Ethiopian montane rainforests

    OpenAIRE

    Aerts, Raf; Berecha, Gezahegn; Gijbels, Pieter; Hundera, Kitessa; Vandepitte,Katrien; Van Glabeke, Sabine; Muys, Bart; Roldan-Ruiz, Isabel; Honnay, Olivier

    2012-01-01

    The montane rainforests of SW Ethiopia are the primary centre of diversity of Coffea arabica and the origin of all Arabica coffee cultivated worldwide. This wild gene pool is potentially threatened by forest fragmentation and degradation, and by introgressive hybridisation with locally improved coffee varieties. We genotyped 703 coffee shrubs from unmanaged and managed coffee populations, using 24 microsatellite loci. Additionally, we genotyped 90 individuals representing 23 Ethiopian cult...

  4. "Fine-scale climatic variation drives altitudinal niche partitioning of tabanid flies in a tropical montane cloud forest, Ecuadorian Choco"

    OpenAIRE

    Cárdenas Muñoz, Rafael Enrique

    2015-01-01

    In montane systems, global warming may lead communities to disassemble by forcing organisms to shift their distributions to higher elevations or by causing the extinction of those that are unable to adapt. To predict which species are most at risk from environmental change, physiological responses to multiple factors must be measured in natural conditions at fine spatial and temporal scales. To examine the potential drivers of elevational distributions in tabanid flies, specimens were exha...

  5. Hemibeltrania urbanodendrii sp. nov. and Pseudobeltrania angamosensis: new fungal records from the brazilian tropical seasonal semi-deciduous montane forest

    OpenAIRE

    Ronaldo de Castro Fernandes; Denise Castro Lustosa; Robert Weingart Barreto; José Luiz Bezerra

    2007-01-01

    The new species Hemibeltrania urbanodendrii, associated to leaf-spots on Urbanodendron verrucosum (Lauracea) and Pseudobeltrania angamosensis, associated with leaf-spots on Virola gardneri (Myristicaceae), are recorded for the first time in Brazil. They represent additions to the mycobiota of the Tropical Seasonal Semi-Deciduous Montane Forest in Viçosa (Minas Gerais, Brazil), a highly threatened ecosystem.Novas ocorrências de fungos relacionados a manchas foliares são apresentadas: Hemibeltr...

  6. Scale-dependent effects of post-fire canopy cover on snowpack depth in montane coniferous forests.

    Science.gov (United States)

    Stevens, Jens T

    2017-09-01

    Winter snowpack in dry montane regions provides a valuable ecosystem service by storing water into the growing season. Wildfire in coniferous montane forests has the potential to indirectly affect snowpack accumulation and ablation (mass loss) rates by reducing canopy cover, which reduces canopy interception of snow but also increases solar radiation and wind speed. These counteracting effects create uncertainty regarding the canopy conditions that maximize post-fire snowpack duration, which is of concern as montane regions across the western United States experience increasingly warm, dry winters with below-average snowpack. The net effect of wildfire on snowpack depth and duration across the landscape is uncertain, and likely scale dependent. In this study, I tested whether intermediate levels of wildfire severity maximize snowpack depth by increasing accumulation while slowing ablation, using gridded, repeated snow depth measurements from three fires in the Sierra Nevada of California. Increasing fire severity had a strong negative effect on snowpack depth, suggesting that increased ablation after fire, rather than increased accumulation, was the dominant control over snowpack duration. Contrary to expectations, the unburned forest condition had the highest overall snowpack depth, and mean snow depth among all site visits was reduced by 78% from unburned forest to high-severity fire. However, at the individual tree scale, snowpack depth was greater under canopy openings than underneath canopy, controlling for effects of fire severity and aspect. This apparent paradox in snowpack response to fire at the stand vs. individual tree scales is likely due to greater variation in canopy cover within unburned and very low severity areas, which creates smaller areas for snow accumulation while reducing ablation via shading. Management efforts to maximize snowpack duration in montane forests should focus on retaining fine-scale heterogeneity in forest structure. © 2017 by

  7. Species delimitation, phylogeny and evolutionary demography of co-distributed, montane frogs in the southern Brazilian Atlantic Forest.

    Science.gov (United States)

    Firkowski, Carina R; Bornschein, Marcos R; Ribeiro, Luiz F; Pie, Marcio R

    2016-07-01

    The Brazilian Atlantic Forest (BAF) is recognized as one of the world's biodiversity hotspots, with even more species per unit of area than the Amazon, however the mechanisms that led to such astonishing diversity are yet to be fully understood. In this study, we investigate the diversification of two co-distributed frog genera associated with montane areas of southern BAF: Melanophryniscus (Bufonidae) and Brachycephalus (Brachycephalidae). Species delimitation methods using mitochondrial and nuclear loci supported the existence of a remarkable number of highly endemic species in each genus, most of which occupy only one or a few adjacent mountaintops. Their timing of diversification was highly congruent, supporting recent speciation events within the past 600 thousand years. Extended Bayesian skyline plots indicate that most populations have remained relatively stable in size across the evolutionary past, with recent growth after 0.15My, suggesting that the drastic changes found in previous studies on lowland frog species were not shared by these montane taxa. These results are consistent with the existence of a montane refugium in southern BAF, allowing species persistence through the climatic shifts experienced along the BAF during the Quaternary. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. 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.

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

    Science.gov (United States)

    Flousek, Jiří; Telenský, Tomáš; Hanzelka, Jan; Reif, Jiří

    2015-01-01

    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.

  10. Recent rates of carbon accumulation in montane fens ofYosemite National Park, California, U.S.A.

    Science.gov (United States)

    Drexler, Judith; Fuller, Christopher C.; Orlando, James; Moore, Peggy E.

    2016-01-01

    Little is known about recent rates of carbon storage in montane peatlands, particularly in the western United States. Here we report on recent rates of carbon accumulation (past 50 to 100 years) in montane groundwater-fed peatlands (fens) of Yosemite National Park in central California, U.S.A. Peat cores were collected at three sites ranging in elevation from 2070 to 2500 m. Core sections were analyzed for bulk density, % organic carbon, and 210Pb activities for dating purposes. Organic carbon densities ranged from 0.026 to 0.065 g C cm-3. Mean vertical accretion rates estimated using210Pb over the 50-year period from ∼1960 to 2011 and the 100-year period from ∼1910 to 2011 were 0.28 (standard deviation = ±0.09) and 0.18 (±-0.04) cm yr-1, respectively. Mean carbon accumulation rates over the 50- and 100-year periods were 95.4 (±25.4) and 74.7 (±17.2) g C m-2 yr-1, respectively. Such rates are similar to recent rates of carbon accumulation in rich fens in western Canada, but more studies are needed to definitively establish both the similarities and differences in peat formation between boreal and temperate montane fens.

  11. Demographic processes in the montane Atlantic rainforest: molecular and cytogenetic evidence from the endemic frog Proceratophrys boiei.

    Science.gov (United States)

    Amaro, Renata Cecília; Rodrigues, Miguel Trefaut; Yonenaga-Yassuda, Yatiyo; Carnaval, Ana Carolina

    2012-03-01

    Historical climatic refugia predict genetic diversity in lowland endemics of the Brazilian Atlantic rainforest. Yet, available data reveal distinct biological responses to the Last Glacial Maximum (LGM) conditions across species of different altitudinal ranges. We show that species occupying Brazil's montane forests were significantly less affected by LGM conditions relative to lowland specialists, but that pre-Pleistocene tectonics greatly influenced their geographic variation. Our conclusions are based on palaeoclimatic distribution models, molecular sequences of the cytochrome b, 16S, and RAG-1 genes, and karyotype data for the endemic frog Proceratophrys boiei. DNA and chromosomal data identify in P. boiei at least two broadly divergent phylogroups, which have not been distinguished morphologically. Cytogenetic results also indicate an area of hybridization in southern São Paulo. The location of the phylogeographic break broadly matches the location of a NW-SE fault, which underwent reactivation in the Neogene and led to remarkable landscape changes in southeastern Brazil. Our results point to different mechanisms underpinning diversity patterns in lowland versus montane tropical taxa, and help us to understand the processes responsible for the large number of narrow endemics currently observed in montane areas of the southern Atlantic forest hotspot.

  12. Comparison of wood-inhabiting myxomycetes in subalpine and montane coniferous forests in the Yatsugatake Mountains of Central Japan.

    Science.gov (United States)

    Takahashi, Kazunari; Harakon, Yuichi

    2012-05-01

    To demonstrate altitudinal gradients (and resulting temperatures) that affect myxomycete biodiversity and species composition, we statistically compared myxomycete assemblages between a subalpine coniferous forest and a montane pine forest within the region of the Yatsugatake Mountains, Nagano Prefecture, Central Japan. In summer and autumn field surveys during 2003-2010, 53 myxomycete taxa (with varieties treated as species) were observed from 639 records of fruiting bodies in the subalpine forest and 32 taxa were detected from 613 records in the montane forest. There were 20 species in common between the assemblages and the percentage similarity index was 0.400. Myxomycete biodiversity was higher in the subalpine than in the montane forest. Nine myxomycete species were statistically frequent occurrences in the subalpine forest and appeared in autumn: Lamproderma columbinum, Cribraria macrocarpa, Trichia botrytis, Physarum newtonii, Diderma ochraceum, Enteridium splendens, Elaeomyxa cerifera, Trichia verrucosa, and Colloderma oculatum. Five species were restricted to appear in the subalpine forest: Cribraria purpurea, Cribraria rufa, Cribraria ferruginea, Cribraria piriformis, and Lepidoderma tigrinum. Dead wood in the subalpine forest provided a breeding habitat for specific myxomycetes that inhabit cold areas; that is those areas having geographical features of decreasing temperature and increasing elevation, such as the temperate area of Central Japan.

  13. Phenols content and 2-D electrophoresis protein pattern: a promising tool to monitor Posidonia meadows health state

    Directory of Open Access Journals (Sweden)

    Randazzo Davide

    2007-07-01

    Full Text Available Abstract Background The endemic seagrass Posidonia oceanica (L. Delile colonizes soft bottoms producing highly productive meadows that play a crucial role in coastal ecosystems dynamics. Human activities and natural events are responsible for a widespread meadows regression; to date the identification of "diagnostic" tools to monitor conservation status is a critical issue. In this study the feasibility of a novel tool to evaluate ecological impacts on Posidonia meadows has been tested. Quantification of a putative stress indicator, i.e. phenols content, has been coupled to 2-D electrophoretic protein analysis of rhizome samples. Results The overall expression pattern from Posidonia rhizome was determined using a preliminary proteomic approach, 437 protein spots were characterized by pI and molecular weight. We found that protein expression differs in samples belonging to sites with high or low phenols: 22 unique protein spots are peculiar of "low phenols" and 27 other spots characterize "high phenols" samples. Conclusion Posidonia showed phenols variations within the meadow, that probably reflect the heterogeneity of environmental pressures. In addition, comparison of the 2-D electrophoresis patterns allowed to highlight qualitative protein expression differences in response to these pressures. These differences may account for changes in metabolic/physiological pathways as adaptation to stress. A combined approach, based on phenols content determination and 2-D electrophoresis protein pattern, seems a promising tool to monitor Posidonia meadows health state.

  14. Effects of hydrological regime on development of Carex wet meadows in East Dongting Lake, a Ramsar Wetland for wintering waterbirds

    Science.gov (United States)

    Jing, Lei; Lu, Cai; Xia, Yan; Shi, Linlu; Zuo, Aojie; Lei, Jialing; Zhang, Hong; Lei, Guangchun; Wen, Li

    2017-01-01

    Wet meadows are one of the most important ecological components in floodplain, and are among the most dynamic ecosystems. Understanding the development of wet meadows and contributing environmental factors can provide better support for wetland management. Carex meadows in East Dongting Lake National Nature Reserve (EDLNNR) provide vital wintering ground for thousands of migratory waterbirds, and their ecological functions are under threated due to hydrological alternation. We measured wet meadow expansion in EDLNNR from 1989 to 2014, and explored its responses to hydrological and climatic factors within the generalised additive models (GAM) framework. We found an overall expansion of wet meadows over the study period. However, in contrast to many previous studies, our results showed that water level fluctuations at the hydrologic indicator site had only limited impacts on their development. Instead, sampling year, timing of water level recession, and local rainfall exerted significant effects. The effects of sampling year reflected the changes in sedimentation within Dongting Lake; and effects of timing of water withdrawal might be explained by the life history of the dominant sedge species. Our study suggested that the impacts of large scale hydrological alternation on vegetation may operate indirectly through its effects on sediment balance. PMID:28165508

  15. Effects of hydrological regime on development of Carex wet meadows in East Dongting Lake, a Ramsar Wetland for wintering waterbirds

    Science.gov (United States)

    Jing, Lei; Lu, Cai; Xia, Yan; Shi, Linlu; Zuo, Aojie; Lei, Jialing; Zhang, Hong; Lei, Guangchun; Wen, Li

    2017-02-01

    Wet meadows are one of the most important ecological components in floodplain, and are among the most dynamic ecosystems. Understanding the development of wet meadows and contributing environmental factors can provide better support for wetland management. Carex meadows in East Dongting Lake National Nature Reserve (EDLNNR) provide vital wintering ground for thousands of migratory waterbirds, and their ecological functions are under threated due to hydrological alternation. We measured wet meadow expansion in EDLNNR from 1989 to 2014, and explored its responses to hydrological and climatic factors within the generalised additive models (GAM) framework. We found an overall expansion of wet meadows over the study period. However, in contrast to many previous studies, our results showed that water level fluctuations at the hydrologic indicator site had only limited impacts on their development. Instead, sampling year, timing of water level recession, and local rainfall exerted significant effects. The effects of sampling year reflected the changes in sedimentation within Dongting Lake; and effects of timing of water withdrawal might be explained by the life history of the dominant sedge species. Our study suggested that the impacts of large scale hydrological alternation on vegetation may operate indirectly through its effects on sediment balance.

  16. 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

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

    Directory of Open Access Journals (Sweden)

    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

  18. Dinitrogen emissions as an overlooked key component of the N balance of montane grasslands

    Science.gov (United States)

    Zistl-Schlingmann, Marcus; Feng, Jinchao; Kiese, Ralf; Stephan, Ruth; Dannenmann, Michael

    2017-04-01

    Numerous studies have been conducted on the emission dynamics and annual budget of the atmospheric pollutants and primary or secondary greenhouse gases NOx, NH3 and N2O, i.e. gaseous N losses which can play an important role in the N budget of ecosystems. Due to still existing methodical problems in their quantification, considerably less is known on soil dinitrogen (N2) emissions, an inert gas with no hazardous effects on the environment. Understanding of soil N2 emissions however may be important to better understand and manage the N balance of ecosystems and also to mitigate the emissions of the precursor and potent greenhouse gas N2O. Here we quantified soil N2 emissions from montane grasslands used for dairy farming as affected by climate change simulation (reduced annual precipitation, increased temperature). For this purpose, plant-soil-mesocosms were brought from field sites of different elevation to the laboratory for direct simultaneous quantification of soil N2 and N2O emissions by use of the Helium soil core method. Immediately after the measurements, the plant-soil mesocosms were reburied at the sites. Using this approach we found that under current climate conditions, soil N2 emissions exceeded soil N2O emissions by several orders of magnitude and increased from 25 kg N ha-1 year-1 (present climate) to 50 kg N ha-1 year-1 (climate change treatment). Because this approach based on monthly sampling cannot accurately consider N gas emission peaks after manure fertilization, measurements were supplemented by a laboratory incubation approach. In this experiment, the response of all N gas emissions (NH3, NO, N2O, N2) to manure fertilization (50 kg N ha-1) was monitored with subdaily temporal resolution until emissions had diminished. Total N gas losses amounted to roughly half of the supplied N by manure application. Surprisingly, we found that N2 but not NH3 dominated fertilizer-derived gaseous N losses, accounting for 78 to 85 % of total gaseous N losses

  19. Energy Balance Alterations Due to Cropland Conversion in a Tropical Montane Environment: Shaded Coffee to Sugarcane

    Science.gov (United States)

    Alvarado-Barrientos, M. S.; Holwerda, F.; Salazar-Martinez, D.

    2014-12-01

    Although land use change (LUC) is an important driver of changes in climate, very limited field observations of atmosphere-landscape interactions exist in tropical montane zones to examine the extent to which LUCs affect climate locally and regionally. The lack of ground observations hampers the evaluation of satellite-derived datasets of land surface parameters as well as the validation of regional climate models. The first results of an ongoing study of the climate effects of a LUC trajectory in the lower montane region (1200 m a.s.l.) of central Veracruz, Mexico, are presented. The radiation balance, turbulent fluxes and soil heat flux were measured in order to obtain field-derived land surface parameters (albedo and Bowen ratio) of two contrasting land uses: shaded coffee (CO) and sugarcane (SU) plantations. Measurements were conducted on days representing different seasons and crop stages during 2014: cold-dry (January), warm-dry (March) and warm-wet (July). Average noon-time albedo was higher for SU than for CO (0.14 vs. 0.11). Soil heat flux was on average 13% and 12% of net radiation for SU and CO, respectively. Preliminary turbulent flux calculations indicate that noon-time Bowen ratio was higher for sugar cane (range: 1.0-1.5) compared to shaded coffee (range: 0.5-1.0). Seasonal (and crop-stage) changes affected the surface parameters of SU mostly. For example, the SU Bowen ratio increased with decreasing soil moisture, indicating soil moisture limitation for transpiration reducing latent heat flux. In contrast, the shaded coffee Bowen ratio remained relatively constant across measuring periods. The energy balance closure was 80% (pending complete eddy covariance data corrections). These results indicate that the conversion of shaded coffee to sugarcane result in a drier and hotter lower atmosphere. Next steps include examining the implications of these local changes for regional climate, with special attention to cloud formation, using a regional model

  20. Influence of submarine springs and wastewater on nutrient dynamics of Caribbean seagrass meadows

    Science.gov (United States)

    Carruthers, T. J. B.; van Tussenbroek, B. I.; Dennison, W. C.

    2005-08-01

    The east coast of the Yucatan Peninsula, Mexico, consists of highly permeable limestone, such that surface flow and rivers are absent in this region. Extensive underground cave systems connect sink holes (cenotes) to submarine springs (ojos de aqua), which vent into the seagrass meadows of the adjacent oligotrophic coastal lagoons. This study investigated the potential for these submarine springs to influence nutrient processes within seagrass meadows, by assessing nutrient status of Thalassia testudinum meadows in two contrasting coastal lagoons along the north eastern Yucatan peninsula. Tissue nutrient concentrations as well as δ 15N values of T. testudinum were surveyed in the Puerto Morelos Reef Lagoon and the Nichupte Lagoon System, Cancun Hotel Zone, during an extended dry period and again following heavy rainfall. After a period of heavy rainfall, T. testudinum near submarine springs in Puerto Morelos Reef Lagoon had exceptionally high leaf tissue phosphorus concentrations of 0.38±0.06%. These submarine springs may have been a direct source of phosphorus and/or a source of iron to this very iron limited carbonate system. Thalassia testudinum nutrient concentrations suggest that nitrogen loading to the Nichupte Lagoon System is regionally high and has increased over the past decade (mean leaf N: 2.04% N in 1991 to 2.71% N in 2002). Nitrogen content in leaf tissue of T. testudinum was significantly higher within the poorly flushed Nichupte Lagoon System (2.93±0.12% N) than in the well-flushed Puerto Morelos Reef Lagoon (1.80±0.07% N). Stable isotope ratios of nitrogen suggest that this high and increasing nitrogen loading within the Nichupte Lagoon System is a result of wastewater nitrogen (δ 15N 9.06±0.07 in northern Nichupte Lagoon System vs. 1.69±0.07 in Puerto Morelos Reef Lagoon).

  1. Cosc's Head (Onobrychis viciifolia Scop. Site Properties on Mountain and Lowland Meadows and Their Agricultural Value

    Directory of Open Access Journals (Sweden)

    V. Ivanek

    1998-06-01

    Full Text Available In the Kalnik piedmont region parallel researches of cock ' s head Onobrychis viciifolia Scop. site soil properties and lawn botanical composition were performed on 2 locations in mountain association Bromo-Plantaginetum mediae and 6 locations in lowland meadow in association Arrhenatheretum elatioris. Some physical and chemical soil properties on each location were determined at the soil depths 0-15, 18-22 and 25-30 cm with usual methods. Botanical composition of lawn was determined by the method Klapp et al. modified by Šoštarić-Pisačić and Kovačević. It was determined that Cock's head sites in association Arrhenatheretum elatioris give significantly higher hay yields than Cock's head sites in association Bromo-Plantaginetum mediae. Hay quality in both associations is good. On the researched locations soil property differences among locations were determined. Correlations and regressions between single soil properties and Cock's head percentage in botanical composition of meadow associations were determined, with the help of computer. From correlations and regressions it is visible that with increase of soil supply with physiological active phosphorus, with decrease of clay soil particles < 0.002 mm and with increase of soil particles 2 - 0.2 mm increases percentage of Cock's head (Onobrychis viciifolia in botanical composition of meadow associations. On the same sites correlation between soil reaction (pH and soil supply with physiological active magnesium (Mg, and manganese (Mn respectively were determined. Plain Cock's head (Onobrychis viciifolia Scop. sites in associations Arrhenatheretum elatioris on the alluvial carbonate ground can provide convenient conditions for all arable plants in particular for clovers-grasses mixtures based on Cock s head (Onobrychis sativa or alfalfa (Medicago sativa.

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

    Directory of Open Access Journals (Sweden)

    Shu Liao

    Full Text Available 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. Temporal trends of littoral fishes at deep Posidonia oceanica seagrass meadows in a temperate coastal zone

    Science.gov (United States)

    Deudero, Salud; Morey, Gabriel; Frau, Antoni; Moranta, Joan; Moreno, Isabel

    Seasonal abundance and biomass of littoral fish at Posidonia oceanica seagrass meadows were characterized throughout an annual cycle in Mediterranean waters. Bimonthly beam trawl hauls were performed between 18 and 38 m depth at 4 sites sampling from 2 locations. Approximately 8230 littoral fish were collected belonging to 25 families and 51 species with Labridae and Sparidae families being predominant in terms of abundance. Mean fish abundance was 92 ± 7.5 individuals · 1000 m - 2 peaking in March, April and September and total abundance showed significant statistical differences between May and October. Densities of Diplodus annularis, Gobius sp., Mullus surmuletus, Parablennius tentacularis, Sarpa salpa, Sciaena umbra, Scorpaena porcus, Serranus cabrilla, Symphodus ocellatus, Symphodus rostratus, Symphodus tinca and Synodus saurus differed significantly between seasons. Total community biomass varied significantly along the year with maximum values observed in July (1500 g · 1000 m - 2 ) and minimum biomass recorded in October. The number of species ranged between 5 in January and 21 in July while the total number of individuals was 293 in July and 21 in September, and Margalef diversity index differed between 4.11 in July and 1.3 in January. Biomass peaked in summer linked mainly to the increase of S. porcus, Serranus scriba and some Symphodus species. Diversity was maximal in July and the larger mean size for most of the fish species was achieved from May to July corresponding to the recruitment peaks of some of the fish species. The SIMPER analysis showed that there are seasonal differences in the trophic roles of the fish communities at seagrass meadows. The temporal patterns observed highlight the multifunctional role of deep seagrass meadows during the summer months when all the measured parameters are maximal. Those observations point out the need for conservation measures to be intensified in the warm season.

  4. Long term changes in Zostera meadows in the Berre lagoon (Provence, Mediterranean Sea)

    Science.gov (United States)

    Bernard, Guillaume; Boudouresque, Charles F.; Picon, Philippe

    2007-07-01

    The Berre lagoon (Provence, France), one of the largest Mediterranean brackish lagoons (155 km 2), was occupied, at the turn of the 20th century, by extensive Zostera meadows ( Zostera marina and probably Zostera noltii; perhaps over 6000 ha). Subsequently, the lagoon was disturbed by urban and industrial pollution and, from 1966, by the diversion of the Durance River. This resulted in a 10-49-fold and 8-31-fold increase of the freshwater and silt inputs, respectively. By means of digital analysis of aerial photographs for the years 1944, 1992, 1998 and 2004, coupled with ground truth for the last three dates, we mapped the Zostera meadows. The replacement of Z. marina by Z. noltii, the latter species being already dominant in the 1970s, was completed in 1990. In parallel to this substitution, the Zostera beds underwent a dramatic decline. Their depth limit, which was (6-9) m in the early 20th century, withdrew to 3.5, 3, 1 and less than 1 m by 1944, the 1970s, 1992 and 1998, respectively. Since 1998, Zostera must be considered as functionally extinct. The total surface area of Zostera meadows was of the order of 1.5 ha in 2004. In an attempt to alleviate disturbance, the input of freshwater and silt from the Durance River was significantly reduced from the early 1980s and 1990s respectively. Similarly, from the 1970s to the 1990s, urban and domestic pollution was drastically reduced. Despite these steps, Zostera meadows continued to shrink to near extinction. The lagoon has shifted from a system dominated by seagrass beds to a system with bare silt bottoms, which now occupy most of the lagoon. The reasons could be, in addition to continuing nutrient inputs, the resuspension of silt, no longer trapped under the seagrass canopy, during wind episodes, which are frequent in the area, and/or the release of nutrients from the bare silt habitat, which would constitute an indication of a possible hysteresis of the system. However, since 2000, the establishment of the

  5. Transformer species in the flora of the Starobilsk grass-meadow steppe (Ukraine

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    Kucher Oksana O.

    2015-12-01

    Full Text Available The results of an investigation of alien species that change the character, condition, form or nature of ecosystems over large areas (transformer species in the flora of the Starobilsk grass-meadow steppe are presented. The check-list of alien plants includes over 386 species of vascular plants, of which 28 are invasive and 6 are transformer species. In this study, the data on the first records of alien species, their distribution history, ecology, occurrence in different plant communities and degree of naturalization were compiled. The distribution maps of transformer species are provided.

  6. Cholinesterase inhibition in meadow voles Microtus pennsylvanicus following field applications of Orthene

    Science.gov (United States)

    Jett, D.A.

    1986-01-01

    Brain acetylcholinesterase activity in field-caught meadow voles (Microtus pennsylvanicus) was depressed after a field-spray of Orthene (acephate: acetylphosphoramidothioic acid O,S-dimethyl ester) by as much as 32% in 1982 and 38% in 1983. Short-term recovery was demonstrated and occurred in a time-dependent fashion in 1982. Plasma cholinesterase levels were move variable but also were depressed. Residues were detected in vegetation samples and in the gastrointestinal tracts of exposed voles. Residues in vegetation were diluted or absent 7 to 8 d following the treatment.

  7. Reclaimed spoil heap from an open-cast mine: analysis of meadow communities

    Energy Technology Data Exchange (ETDEWEB)

    Novak, J.; Hakl, J.; Steklova, J.; Ceska, J.; Dvorakova, E. [Czech University for Life Science Prague, Prague (Czech Republic)

    2008-07-01

    An evaluation of the vegetation on the reclaimed spoil heap of material deposited from the overlaying rock of an open-cast brown coal mine. The application of standard geobotanical research methods with statistical data analysis. Under the present management conditions desirable meadow taxa keep their constancy: the reduction of ruderal and weed species is evident, though statistically insignificant. For the variability of species composition over time, and in particular by the location of releves taken, the strong influence of substrate heterogeneity i.e. (in addition to exposure, humidity etc.) is inferred.

  8. Biogas production from ensiled meadow grass; effect of mechanical pretreatments and rapid determination of substrate biodegradability via physicochemical methods.

    Science.gov (United States)

    Tsapekos, P; Kougias, P G; Angelidaki, I

    2015-04-01

    As the biogas sector is rapidly expanding, there is an increasing need in finding new alternative feedstock to biogas plants. Meadow grass can be a suitable co-substrate and if ensiled it can be supplied to biogas plants continuously throughout the year. Nevertheless, this substrate is quite recalcitrant and therefore efficient pretreatment is needed to permit easy access of microbes to the degradable components. In this study, different mechanical pretreatment methods were applied on ensiled meadow grass to investigate their effect on biomass biodegradability. All the tested pretreatments increased the methane productivity and the increase ranged from 8% to 25%. The best mechanical pretreatment was the usage of two coarse mesh grating plates. Additionally, simple analytical methods were conducted to investigate the possibility of rapidly determining the methane yield of meadow grass. Among the methods, electrical conductivity test showed the most promising calibration statistics (R(2)=0.68).

  9. Use of semi-quantitative kit methods to study the heterotrophic bacterial community of Posidonia oceanica meadows: Limits and possible applications

    Science.gov (United States)

    Richir, J.; Velimirov, B.; Poulicek, M.; Gobert, S.

    2012-08-01

    Rapid, easy and low cost semi-quantitative methods were tested to study the heterotrophic bacterial community of Posidonia oceanica meadows and were compared to techniques commonly used in microbial ecology. Free and pore-water bacterial densities were estimated by luminescence, and principal enzymatic activities, metabolic capabilities and benthic mineralisation processes were studied with microtitration methods: ApiZym galleries, Biolog microplates and BART™ tests. Bacterial densities varied little throughout the year and were around 5.0·105 and 6.0·106 cells ml-1 of free and pore-water, respectively. The combined use of the ApiZym gallery and the Biolog microtitration plate permitted highlighting bacterial enzymatic activities susceptible to degrade principal organic polymers present in the Posidonia meadow, and to correlate these enzymatic activities to the subsequent potential utilization of resulting monomeric products. Levels of enzymatic activities (1.80-8.36 nmolessubstrates h-1 ml-1) and energetic bacterial metabolism (1.80-6.42 nmolessubstrates h-1 ml-1) presented seasonality relying on the temperature regime and on the primary production (Posidonia and phytoplankton). Main mineralization processes of buried organic matter through sulfate and iron reduction activities were successfully detected. Despite the complexity of the studied ecosystem, results obtained by this semi-quantitative approach, compared to studies applying commonly used methods in microbial ecology, highlighted the same bacterial dominant key processes. Their low cost, rapid and easy use, and the low level of expertise and sophistication they require means that these techniques are of use to many employed in environmental surveys.

  10. 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.

  11. 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.

  12. Pervasive Effects of Wildfire on Foliar Endophyte Communities in Montane Forest Trees.

    Science.gov (United States)

    Huang, Yu-Ling; Devan, M M Nandi; U'Ren, Jana M; Furr, Susan H; Arnold, A Elizabeth

    2016-02-01

    Plants in all terrestrial ecosystems form symbioses with endophytic fungi that inhabit their healthy tissues. How these foliar endophytes respond to wildfires has not been studied previously, but is important given the increasing frequency and intensity of severe wildfires in many ecosystems, and because endophytes can influence plant growth and responses to stress. The goal of this study was to examine effects of severe wildfires on endophyte communities in forest trees, with a focus on traditionally fire-dominated, montane ecosystems in the southwestern USA. We evaluated the abundance, diversity, and composition of endophytes in foliage of Juniperus deppeana (Cupressaceae) and Quercus spp. (Fagaceae) collected contemporaneously from areas affected by recent wildfire and paired areas not affected by recent fire. Study sites spanned four mountain ranges in central and southern Arizona. Our results revealed significant effects of fires on endophyte communities, including decreases in isolation frequency, increases in diversity, and shifts in community structure and taxonomic composition among endophytes of trees affected by recent fires. Responses to fire were similar in endophytes of each host in these fire-dominated ecosystems and reflect regional fire-return intervals, with endophytes after fire representing subsets of the regional mycoflora. Together, these findings contribute to an emerging perspective on the responses of diverse communities to severe fire, and highlight the importance of considering fire history when estimating endophyte diversity and community structure for focal biomes.

  13. A new species of Noblella (Amphibia, Anura, Craugastoridae from the humid montane forests of Cusco, Peru

    Directory of Open Access Journals (Sweden)

    Alessandro Catenazzi

    2015-08-01

    Full Text Available A new species of Noblella is described from the humid montane forest of the Región Cusco in Peru. Specimens were collected at 2330–2370 m elevation in Madre Selva, near Santa Ana, in the province of La Convención. The new species is readily distinguished from all other species of Noblella by having a broad, irregularly shaped, white mark on black background on chest and belly. The new species further differs from known Peruvian species of Noblella by the combination of the following characters: tympanic membrane absent, small tubercles on the upper eyelid and on dorsum, tarsal tubercles or folds absent, tips of digits not expanded, no circumferential grooves on digits, dark brown facial mask and lateral band extending from the tip of the snout to the inguinal region. The new species has a snout-to-vent length of 15.6 mm in one adult male and 17.6 mm in one adult female. Like other recently described species in the genus, this new Noblella inhabits high-elevation forests in the Andes and likely has a restricted geographic distribution.

  14. 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.

  15. 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.

  16. Epiphytic and terrestrial mycorrhizas in a lower montane Costa Rican cloud forest.

    Science.gov (United States)

    Rains, Kai Coshow; Nadkarni, Nalini M; Bledsoe, Caroline S

    2003-10-01

    The epiphyte community is the most diverse plant community in neotropical cloud forests and its collective biomass can exceed that of the terrestrial shrubs and herbs. However, little is known about the role of mycorrhizas in this community. We assessed the mycorrhizal status of epiphytic (Araceae, Clusiaceae, Ericaceae, and Piperaceae) and terrestrial (Clusiaceae, Ericaceae) plants in a lower montane cloud forest in Costa Rica. Arbuscular mycorrhizas were observed in taxa from Araceae and Clusiaceae; ericoid mycorrhizas were observed in ericaceous plants. This is the first report of intracellular hyphal coils characteristic of ericoid mycorrhizas in roots of Cavendishia melastomoides, Disterigma humboldtii, and Gaultheria erecta. Ericaceous roots were also covered by an intermittent hyphal mantle that penetrated between epidermal cells. Mantles, observed uniquely on ericaceous roots, were more abundant on terrestrial than on epiphytic roots. Mantle abundance was negatively correlated with gravimetric soil water content for epiphytic samples. Dark septate endophytic (DSE) fungi colonized roots of all four families. For the common epiphyte D. humboldtii, DSE structures were most abundant on samples collected from exposed microsites in the canopy. The presence of mycorrhizas in all epiphytes except Peperomia sp. suggests that inoculum levels and environmental conditions in the canopy of tropical cloud forests are generally conducive to the formation of mycorrhizas. These may impact nutrient and water dynamics in arboreal ecosystems.

  17. A new species of Noblella (Amphibia, Anura, Craugastoridae) from the humid montane forests of Cusco, Peru.

    Science.gov (United States)

    Catenazzi, Alessandro; Uscapi, Vanessa; von May, Rudolf

    2015-01-01

    A new species of Noblella is described from the humid montane forest of the Región Cusco in Peru. Specimens were collected at 2330-2370 m elevation in Madre Selva, near Santa Ana, in the province of La Convención. The new species is readily distinguished from all other species of Noblella by having a broad, irregularly shaped, white mark on black background on chest and belly. The new species further differs from known Peruvian species of Noblella by the combination of the following characters: tympanic membrane absent, small tubercles on the upper eyelid and on dorsum, tarsal tubercles or folds absent, tips of digits not expanded, no circumferential grooves on digits, dark brown facial mask and lateral band extending from the tip of the snout to the inguinal region. The new species has a snout-to-vent length of 15.6 mm in one adult male and 17.6 mm in one adult female. Like other recently described species in the genus, this new Noblella inhabits high-elevation forests in the Andes and likely has a restricted geographic distribution.

  18. 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.

  19. A montane Mediterranean climate supports year-round photosynthesis and high forest biomass.

    Science.gov (United States)

    Kelly, Anne E; Goulden, Michael L

    2016-04-01

    The mid-elevation forest of California's Sierra Nevada poses a bioclimatic paradox. Mid-elevation trees experience a montane Mediterranean climate, with near-freezing winter days and rain-free summers. The asynchrony between warmth and water input suggests low primary production, limited by photosynthetic dormancy in winter cold, and again in summer and early autumn with drought, yet this forest is characterized by tall trees and high biomass. We used eddy covariance in a mid-elevation Sierra stand to understand how winter cold and summer drought limit canopy photosynthesis and production. The trees exhibited canopy photosynthesis year-round. Trees avoided winter dormancy, and daytime CO2uptake continued despite a deep snowpack and near-freezing temperatures. Photosynthesis on sunny days continued at half of maximum rates when air temperature was 0 °C. Likewise, the vegetation avoided summer drought dormancy, and high rates of daytime CO2uptake and transpiration continued despite a 5-month period with only negligible water input. We attribute this drought avoidance to deep rooting and availability of deep soil water. Year-round photosynthesis helps explain the large biomass observed in the Sierra Nevada, and implies adaptive strategies that may contribute to the resiliency or vulnerability of Sierran vegetation to climate change.

  20. Elevational ranges of birds on a tropical montane gradient lag behind warming temperatures.

    Directory of Open Access Journals (Sweden)

    German Forero-Medina

    Full Text Available BACKGROUND: Species may respond to a warming climate by moving to higher latitudes or elevations. Shifts in geographic ranges are common responses in temperate regions. For the tropics, latitudinal temperature gradients are shallow; the only escape for species may be to move to higher elevations. There are few data to suggest that they do. Yet, the greatest loss of species from climate disruption may be for tropical montane species. METHODOLOGY/PRINCIPAL FINDINGS: We repeat a historical transect in Peru and find an average upward shift of 49 m for 55 bird species over a 41 year interval. This shift is significantly upward, but also significantly smaller than the 152 m one expects from warming in the region. To estimate the expected shift in elevation we first determined the magnitude of warming in the locality from historical data. Then we used the temperature lapse rate to infer the required shift in altitude to compensate for warming. The range shifts in elevation were similar across different trophic guilds. CONCLUSIONS: Endothermy may provide birds with some flexibility to temperature changes and allow them to move less than expected. Instead of being directly dependent on temperature, birds may be responding to gradual changes in the nature of the habitat or availability of food resources, and presence of competitors. If so, this has important implications for estimates of mountaintop extinctions from climate change.

  1. 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.

  2. A new species of Cladophialophora (hyphomycetes) from boreal and montane bryophytes.

    Science.gov (United States)

    Davey, Marie L; Currah, Randolph S

    2007-01-01

    During a survey of bryophilous fungi from boreal and montane habitats in central Alberta, a hitherto undescribed species of Cladophialophora was recovered from Polytrichum juniperinum, Aulacomnium palustre, and Sphagnum fuscum. On potato dextrose agar (PDA) colonies grew slowly, attaining a diameter of 25 mm after 30 d, were dark grey, velvety, radially sulcate, and convolute and cracked at the centre. Micronematous conidiophores gave rise to branched chains of small (1-2 x 8-22 microm), cylindrical to fusiform conidia with truncate, swollen scars at each end. Phylogenies built on the ITS and ribosomal SSU regions indicate the isolates form a monophyletic clade within the family Herpotrichiellaceae (Chaetothyriales) that is composed of two geographically based groups, each with 99% within-group sequence similarity and 97-98% between-group sequence similarity. A teleomorph has not been found but would likely be similar to species of Capronia. In vitro inoculation of the isolates onto axenically grown P. juniperinum produced no discernible host symptoms, and host penetration could not be detected using light microscopy. The production of polyphenol oxidases by the fungus and the role of other Cladophialophora species as latent endophytes and saprobes suggest that a potential role for the fungus is the degradation of the polyphenol-rich cell walls of mosses. A dichotomous key to species of the genus Cladophialophora is provided.

  3. 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.

  4. Climate change impacts on the water balance of coastal and montane rainforests in northern Queensland, Australia

    Science.gov (United States)

    Wallace, Jim; McJannet, Dave

    2012-12-01

    SummaryHow the water balance of coastal and montane rainforests in northern Queensland could change in response to climate change was examined using physically based models of interception and transpiration along with long term weather records. Future rainfall and temperature changes were based on the most recent climate modelling for the region and were assumed to fall within the range ±20% for rainfall with a temperature increase of 1-3 K. Climate change will affect the water balance of Australian rainforests primarily via rainfall changes rather than temperature. Any given change in rainfall produces a greater change in downstream runoff, the amplification ranging from 1.1 to 1.5 in the wet season to a factor of 12 in the dry season. Changes in wet season rainfall (80% of the annual total) dominate the total annual amount of water released for downstream flow, but dry season rainfall (20% of the annual total) changes are also very important as they affect onset and the duration of the period when there is no runoff. This period is currently ˜110 days and this would change by ±30 days under the above climate scenarios. There are also potential in situ impacts of climate change that affect how long the rainforest canopy is wet, which may have important implications for the epiphytes and mosses that depend on these wet canopy conditions. Similarly there may be significant impacts on downstream freshwater species whose life cycles are adapted to the current dry season flow regime.

  5. FLORISTIC CHANGES ALONG THE TOPOGRAPHICAL GRADIENT IN MONTANE GRASSLANDS IN MONTI PICENTINI (CAMPANIA, SW ITALY

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    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.

  6. FLORISTIC CHANGES ALONG THE TOPOGRAPHICAL GRADIENT IN MONTANE GRASSLANDS IN MONTI PICENTINI (CAMPANIA, SW ITALY

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    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.

  7. Holocene fire and vegetation dynamics in a montane forest, North Cascade Range, Washington, USA

    Science.gov (United States)

    Prichard, Susan J.; Gedalof, Ze'ev; Oswald, W. Wyatt; Peterson, David L.

    2009-07-01

    We reconstructed a 10,500-yr fire and vegetation history of a montane site in the North Cascade Range, Washington State based on lake sediment charcoal, macrofossil and pollen records. High-resolution sampling and abundant macrofossils made it possible to analyze relationships between fire and vegetation. During the early Holocene (> 10,500 to ca. 8000 cal yr BP) forests were subalpine woodlands dominated by Pinus contorta. Around 8000 cal yr BP, P. contorta sharply declined in the macrofossil record. Shade tolerant, mesic species first appeared ca. 4500 cal yr BP. Cupressus nootkatensis appeared most recently at 2000 cal yr BP. Fire frequency varies throughout the record, with significantly shorter mean fire return intervals in the early Holocene than the mid and late Holocene. Charcoal peaks are significantly correlated with an initial increase in macrofossil accumulation rates followed by a decrease, likely corresponding to tree mortality following fire. Climate appears to be a key driver in vegetation and fire regimes over millennial time scales. Fire and other disturbances altered forest vegetation at shorter time scales, and vegetation may have mediated local fire regimes. For example, dominance of P. contorta in the early Holocene forests may have been reinforced by its susceptibility to frequent, stand-replacing fire events.

  8. Sap flow of Castanopsis jianfengensis and its relationship with environmental factors in a tropical montane rainforest

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Using thermal dissipation and the ICT-2000TE equipment made in Australia,the sap flow of Castanopsis jianfengensis and various environmental factors were measured simultaneously in a mixed tropical montane rainforest at Jianfengling Nature Forest Reserve (18°36'N,108°52'E,860 m elevation) during the dry and rainy seasons of 2002.The results show that sap flow velocity of C jianfengensis exhibited a monopeak pattern on clear days and a multi-peak pattern on cloudy or rainy days.Sap flow velocity had significant positive correlations with solar radiation,air temperature,vapor pressure deficit and wind speed and a negative correlation with air relative humidity.In the dry season,sap flow velocity had a significant positive correlation with soil temperature and poor correlation with soil moisture;it was the opposite in the rainy season,indicating that precipitation clearly affected sap flow.Linear regression models between sap flow and environmental factors were established and were significant at the 0.005 level of probability.The mean transpiration rates of C.jianfengensis were 103.5 and 41.3 kg/d in our single tree and 1.94 and 0.77 mm/d in stand level in the dry and rainy season,respectively.

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

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    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

  10. 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.

  11. 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.

  12. Soil bacterial community responses to warming and grazing in a Tibetan alpine meadow.

    Science.gov (United States)

    Li, Yaoming; Lin, Qiaoyan; Wang, Shiping; Li, Xiangzhen; Liu, Wentso; Luo, Caiyun; Zhang, Zhenhua; Zhu, Xiaoxue; Jiang, Lili; Li, Xine

    2016-01-01

    Warming and grazing significantly affect the structure and function of an alpine meadow ecosystem. Yet, the responses of soil microbes to these disturbances are not well understood. Controlled asymmetrical warming (+1.2/1.7°C during daytime/nighttime) with grazing experiments were conducted to study microbial response to warming, grazing and their interactions. Significant interactive effects of warming and grazing were observed on soil bacterial α-diversity and composition. Warming only caused significant increase in bacterial α-diversity under no-grazing conditions. Grazing induced no substantial differences in bacterial α-diversity and composition irrespective of warming. Warming, regardless of grazing, caused a significant increase in soil bacterial community similarity across space, but grazing only induced significant increases under no-warming conditions. The positive effects of warming on bacterial α-diversity and grazing on community similarity were weakened by grazing and warming, respectively. Soil and plant variables explained well the variations in microbial communities, indicating that changes in soil and plant properties may primarily regulate soil microbial responses to warming in this alpine meadow. The results suggest that bacterial communities may become more similar across space in a future, warmed climate and moderate grazing may potentially offset, at least partially, the effects of global warming on the soil microbial diversity. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. 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.

  14. Vegetation pattern related tc grazing pressure in alpine meadows of Nanda Devi Biosphere Reserve.

    Science.gov (United States)

    Singh, S K; Rai, J P N

    2004-07-01

    The present study aims to analyze the interaction of prevailing biotic pressure on plant species diversity in Nanda Devi Biosphere Reserve (NDBR) which lies in northern part of Uttaranchal hills between 79 degrees 40'E to 80 degrees 05'E longitude and 30 degrees 17' N to 30 degrees 41'N latitude and covers an area of 2236.7 km2. A total of 75 species has been found which included the herbaceous plants viz., grasses, sedges and forbs. Generally, the plants have a short life span of 3-4 months. However, few species persist throughout the growth period i.e. May-October. Phytosociological study performed in plots of varying slope and grazing pressure intensity revealed that the dominant grasses were Danthonia cachemyriana and Poa annua and dominant forbs were Trachydium roylei and Geum elatum in all the plots. Grasses were abundant on west facing slopes while forbs preferred the even topography of east facing meadows. The grasses and sedges together had optimum density during July and August. In general, short lived species exhibited more diversity for one or two months whilst the long lived species exhibited optimum diversity althrough the snow free period. The species diversity is maximum (100%) in moderately grazed bughiyals i.e. Pacchu and minimum in intensively grazed bughiyals i.e. Martoli. The species distribution among the plots was 60-90% contagious and 11.2-38.0% randomirrespective of grazing pressure, thus highlighting the significance of grazing pressure in management of alpine meadows.

  15. 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.

  16. 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.

  17. 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.

  18. Effects of common seagrass restoration methods on ecosystem structure in subtropical seagrass meadows.

    Science.gov (United States)

    Bourque, Amanda S; Fourqurean, James W

    2014-06-01

    Seagrass meadows near population centers are subject to frequent disturbance from vessel groundings. Common seagrass restoration methods include filling excavations and applying fertilizer to encourage seagrass recruitment. We sampled macrophytes, soil structure, and macroinvertebrate infauna at unrestored and recently restored vessel grounding disturbances to evaluate the effects of these restoration methods on seagrass ecosystem structure. After a year of observations comparing filled sites to both undisturbed reference and unrestored disturbed sites, filled sites had low organic matter content, nutrient pools, and primary producer abundance. Adding a nutrient source increased porewater nutrient pools at disturbed sites and in undisturbed meadows, but not at filled sites. Environmental predictors of infaunal community structure across treatments included soil texture and nutrient pools. At the one year time scale, the restoration methods studied did not result in convergence between restored and unrestored sites. Particularly in filled sites, soil conditions may combine to constrain rapid development of the seagrass community and associated infauna. Our study is important for understanding early recovery trajectories following restoration using these methods.

  19. Domes, Ash and Dust - Controls on soil genesis in a montane catchment of the Valles Caldera, New Mexico

    Science.gov (United States)

    Rasmussen, C.; Meding, S. M.; Vazquez, A.; Chorover, J.

    2012-12-01

    Soil genesis in volcanic terrain may be controlled by complex assemblages of parent materials and local topography. The objective of this work was to quantify topographic and parent material controls on soil and catchment evolution in a mixed conifer, montane catchment in the Valles Caldera, New Mexico, as part of the Jemez River Basin Critical Zone Observatory. The field site is a 16 ha catchment at an elevation of 3,000 m, with a frigid soil temperature regime (0-8 *C), ustic soil moisture regime with bimodal precipitation of winter snowfall and convective summer rainfall (880 mm yr-1), and an overstory dominated by spruce and fir with dense grass cover in open areas. The catchment is located on the resurgent Redondo Dome that uplifted shortly after the last major eruption of the Valles Caldera 1.2 My ago. The dome includes a complex assemblage of pre-eruptive caldera materials and extant sedimentary rocks embedded within a welded, hydrothermally altered rhyolitic tuff. We sampled a transect of seven soil profiles spanning the dominant east-west aspect of the catchment across a catena with profiles located in summit, backslope, footslope, and toeslope positions. Soil morphology was described in the field and soil samples analyzed using a range of geochemical and mineralogical techniques including quantitative and qualitative x-ray diffraction of bulk samples and particle size fractions, elemental analysis by x-ray fluorescence, and laser particle size analysis. The data indicated strong landscape position control on soil drainage, grading from well-drained summits to poorly-drained toeslope positions based on the presence/absence of redoximorphic features. The drainage patterns were coupled with downslope thickening of dark, organic matter rich surface horizons, likely a function of both in situ organic matter production and downslope colluvial transport of carbon rich surface materials. Mineralogical and geochemical data indicated clear within profile lithologic

  20. 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.

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

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    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

  2. Comparative distribution of central neuropeptide Y (NPY) in the prairie (Microtus ochrogaster) and meadow (M. pennsylvanicus) vole.

    Science.gov (United States)

    Hostetler, Caroline M; Hitchcock, Leah N; Anacker, Allison M J; Young, Larry J; Ryabinin, Andrey E

    2013-02-01

    Neuropeptide Y (NPY) has been implicated as a modulator of social behavior, often in a species-specific manner. Comparative studies of closely related vole species are particularly useful for identifying neural systems involved in social behaviors in both voles and humans. In the present study, immunohistochemistry was performed to compare NPY-like immunoreactivity (-ir) in brain tissue of the socially monogamous prairie vole and non-monogamous meadow vole. Species differences in NPY-ir were observed in a number of regions including the cortex, extended amygdala, septal area, suprachiasmatic nucleus, and intergeniculate leaf. Meadow voles had higher NPY-ir in all these regions as compared to prairie voles. No differences were observed in the striatum or hippocampus. The extended amygdala and lateral septum are regions that play a key role in regulation of monogamous behaviors such as pair bonding and paternal care. The present study suggests NPY in these regions may be an additional modulator of these species-specific social behaviors. Meadow voles had moderately higher NPY-ir in a number of hypothalamic regions, especially in the suprachiasmatic nucleus. Meadow voles also had much higher levels of NPY-ir in the intergeniculate leaflet, another key region in the regulation of circadian rhythms. Overall, species differences in NPY-ir were observed in a number of brain regions implicated in emotion, stress, circadian, and social behaviors. These findings provide additional support for a role for the NPY system in species-typical social behaviors.

  3. Assessing the hydrological suitability of floodplains for species-rich meadow restoration: a case study of the Thames floodplain, UK

    Directory of Open Access Journals (Sweden)

    2007-01-01

    Full Text Available The physical and chemical environment of a floodplain needs to be assessed to define conservation targets for restoring it to species-rich meadows from agricultural land. A straightforward technique, widely applicable by site managers for assessing the suitability of the hydrological and hydro-chemical regime of a floodplain for wet grassland restoration, has been tested by examining the feasibility of restoring plants characteristic of NVC MG4 and MG8 communities to the Castle Meadows, Wallingford (Oxfordshire, UK. Hydro-chemical suitability has been assessed by comparing phosphorus concentrations with species-rich meadows nearby. The flooding regime was estimated based on a rating curve and a digital elevation model and groundwater levels were measured monthly in dipwells and piezometers. The hydrological regime was then compared with published reference guidelines for communities of conservation interest. For the Castle Meadows, the maximum duration of flood events in autumn and winter exceeded MG4 and MG8 species requirements across half of the site, while the depth of the groundwater table in summer exceeded species requirements in the other half. It was shown that, depending on topography, MG5 or MG13 may be more realistic vegetation targets.

  4. The effect of the shape of gaps on microenvironmental conditions and seedling recruitment in Molinietum caeruleae meadows

    Directory of Open Access Journals (Sweden)

    Kinga Kostrakiewicz-Gierałt

    2015-07-01

    Full Text Available Cessation of the management of semi-natural habitats such as grasslands and meadows contributes to secondary succession and encroachment of native and alien tall-growing perennials, large tussock grasses, shrubs, and trees. Thus, the formation of gaps in the plant canopy and litter, enabling seedling recruitment, appears to be a very effective method for the restoration of several plant communities. The main objective of the research was to assess the effect of the shape of openings on microenvironmental conditions and seedling recruitment in Molinietum caeruleae patches in various habitat conditions. In all study patches, circular and linear openings, comparable in area, were randomly created through the removal of plant canopy and litter layer. The circular gaps presented greater light availability and lower soil humidity than linear openings, while soil temperature within differently shaped openings was similar. Regardless of differences in microenvironmental conditions, the total number of seedlings in differently shaped gaps did not vary considerably. Three plant categories were found: (i those recruited mostly in circular openings, (ii those recruited mostly in linear gaps, (iii those colonizing circular and linear gaps similarly. The colonizers of circular gaps represented various synecological groups (ruderal, grasslands and meadows, young tree communities and diverse life forms (therophytes, hemicryptophytes, chamaephytes, phanerophytes, while the colonizers of linear gaps were meadow and grassland hemicryptophytes. The formation of linear openings contributes to increases in the abundance of meadow taxa, while the creation of circular openings may have a negative effect, contributing to the promotion of the secondary succession process.

  5. GEOMORPHIC CONTROLS ON MEADOW ECOSYSTEMS – INSIGHTS INTO LOCAL PROCESSES USING NEAR-SURFACE SEISMIC TECHNIQUES AND GROUND PENETRATING RADAR

    Science.gov (United States)

    Geomorphic controls on riparian meadows in the Central Great Basin of Nevada are an important aspect in determining the formation of and planning the management of these systems. The current hypothesis is that both alluvial fan sediment and faulted bedrock steps interact to cont...

  6. Biogas production from ensiled meadow grass; effect of mechanical pretreatments and rapid determination of substrate biodegradability via physicochemical methods

    DEFF Research Database (Denmark)

    Tsapekos, Panagiotis; Kougias, Panagiotis; Angelidaki, Irini

    2015-01-01

    As the biogas sector is rapidly expanding, there is an increasing need in finding new alternative feedstock to biogas plants. Meadow grass can be a suitable co-substrate and if ensiled it can be supplied to biogas plants continuously throughout the year. Nevertheless, this substrate is quite reca...

  7. Soil microbial population and enzyme activity related to grazing pressure in alpine meadows of Nanda Devi Biosphere Reserve.

    Science.gov (United States)

    Singh, Sanjeeva K; Rai, J P N

    2004-01-01

    The present study aims to analyze the interaction of prevailing biotic pressure on soil environment with emphasis on its physicochemical and microbiological characteristics determining soil fertility status and thus supporting plant and animal biodiversity in Nanda Devi Biosphere Reserve (NDBR) which is located in northern part of Uttaranchal hills between 79 degrees 40'E to 80 degrees 05'E longitude and 30 degrees 17'N to 30 degrees 41'E latitude. The experimental results revealed that the physico-chemical characteristics (viz., moisture, pH, EC, C, N, P, K, CEC) of soil were maximum in moderately grazed meadow and minimum in intensively grazed meadow. Soil microbial analysis measured in terms of total viable count (TVC) exhibited grazing sensitivity trend being maximum population of bacteria > fungi > actinomycetes. The soil microbial population was positively correlated with soil respiration, dehydrogenase activity, acid phosphatase and microbial biomass, which exhibited uneven trend with grazing pressure. Soil from moderately grazed meadow showed highest microbial count and enzyme activities, whilst intensively grazed meadow showed lowest microbial count and enzyme activities. This depicts the beneficial role of prescribed grazing up to limited extent in management of soil fertility, which might have supported luxuriant growth of a variety of grasses.

  8. Annual balances of CH4 and N2O from a managed fen meadow using eddy covariance flux measurements

    NARCIS (Netherlands)

    Kroon, P.S.; Schrier-Uijl, A.P.; Hensen, A.; Veenendaal, E.M.; Jonker, H.J.J.

    2010-01-01

    Annual terrestrial balances of methane (CH4) and nitrous oxide (N2O) are presented for a managed fen meadow in the Netherlands for 2006, 2007 and 2008, using eddy covariance (EC) flux measurements. Annual emissions derived from different methods are compared. The most accurate annual CH4 flux is ach

  9. GEOMORPHIC CONTROLS ON MEADOW ECOSYSTEMS – INSIGHTS INTO LOCAL PROCESSES USING NEAR-SURFACE SEISMIC TECHNIQUES AND GROUND PENETRATING RADAR

    Science.gov (United States)

    Geomorphic controls on riparian meadows in the Central Great Basin of Nevada are an important aspect in determining the formation of and planning the management of these systems. The current hypothesis is that both alluvial fan sediment and faulted bedrock steps interact to cont...

  10. Nine thousand years of upper montane soil/vegetation dynamics from the summit of Caratuva Peak, Southern Brazil

    Science.gov (United States)

    Scheer, Maurício B.; Pereira, Nuno Veríssimo; Behling, Hermann; Curcio, Gustavo R.; Roderjan, Carlos V.

    2014-12-01

    Biodiversity loss, climate change, and increased freshwater consumption are some of the main environmental problems on Earth. Mountain ecosystems can reduce these threats by providing several positive influences, such as the maintenance of biodiversity, water regulation, and carbon storage, amongst others. The knowledge of the history of these environments and their response to climate change is very important for management, conservation, and environmental monitoring programs. The genesis of the soil organic matter of the current upper montane vegetation remains unclear and seems to be quite variable depending on location. Some upper montane sites in the very extensive coastal Sea Mountain Range present considerable organic matter from the late Pleistocene and other from only the Holocene. Our study was carried out on three soil profiles (two cores in grassland and one in forest) on the Caratuva Peak of the Serra do Ibitiraquire (a sub-range of Sea Mountain Range - Serra do Mar) in Southern Brazil. The δ13C isotopic analyses of organic matter in soil horizons were conducted to detect whether C3 or C4 plants dominated the past communities. Complementarily, we performed a pollen analysis and 14C dating of the humin fraction to obtain the age of the studied horizons. Except for a short and probably drier period (between 6000 and 4500 cal yr BP), C3 plants, including ombrophilous grasses and trees, have dominated the highlands of the Caratuva Peak (Pico Caratuva), as well as the other uppermost summits of the Serra do Ibitiraquire, since around 9000 cal yr BP. The Caratuva region represents a landscape of high altitude grasslands (campos de altitude altomontanos or campos altomontanos) and upper montane rain/cloud forests with soils that most likely contain some organic matter from the late Pleistocene, as has been reported in Southern and Southeastern Brazil for other sites. However, our results indicate that the studied deposits (near the summit) are from the early

  11. Lluís Domènech i Montaner, a la recerca de la ceràmica moderna

    OpenAIRE

    Casanova, Rossend

    2002-01-01

    El 1887, Lluís Doménech i Montaner va rebre l’encàrrec de projectar i construir el Café-Restaurant de l’Exposició Universal de Barcelona de 1888, el que seria l’edifici més rellevant de la seva primera etapa com arquitecte. El resultat fou un edifici estructuralment gran, visualment admirable i arquitectònicament modern, en el que la ceràmica aplicada havia de tenir un gran protagonisme.

  12. Dissolved organic matter transport reflects hillslope to stream connectivity during snowmelt in a montane catchment

    Science.gov (United States)

    Burns, Margaret A.; Barnard, Holly R.; Gabor, Rachel S.; McKnight, Diane M.; Brooks, Paul D.

    2016-06-01

    Dissolved organic matter (DOM) transport is a key biogeochemical linkage across the terrestrial-aquatic interface in headwater catchments, and quantifying the biological and hydrological controls on DOM composition provides insight into DOM cycling at the catchment scale. We evaluated the mobility of DOM components during snowmelt in a montane, semiarid catchment. DOM composition was evaluated on a near-daily basis within the soil and the stream during snowmelt, and was compared to groundwater samples using a site-specific parallel factor analysis (PARAFAC) model derived from soil extracts. The fluorescent component loadings in the interstitial soil water and in the groundwater were significantly different and did not temporally change during snowmelt. In the stream, a transition occurred during snowmelt from fluorescent DOM with higher contributions of amino acid-like components indicative of groundwater to higher humic-like contributions indicative of soil water. Furthermore, we identified a humic-like fluorescent component in the soil water and the stream that is typically only observed in extracted water soluble organic matter from soil which may suggest hillslope to stream connectivity over very short time scales. Qualitative interpretations of changes in stream fluorescent DOM were supported by two end-member mixing analyses of conservative tracers. After normalizing fluorescent DOM loadings for dissolved organic carbon (DOC) concentration, we found that the peak in DOC concentration in the stream was driven by the nonfluorescent fraction of DOM. This study demonstrated how PARAFAC analysis can be used to refine our conceptual models of runoff generation sources, as well as provide a more detailed understanding of stream chemistry dynamics.

  13. 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.

  14. 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.

  15. 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

  16. Primary succession of Hawaiian montane rain forest on a chronosequence of eight lava flows

    Energy Technology Data Exchange (ETDEWEB)

    Kitayama, K.; Mueller-Dombois, D. [Univ. of Hawaii at Manoa, Honolulu, HI, (United States) Dept. of Botany; Vitousek, P.M. [Stanford Univ., Stanford, CA (United States) Dept. of Biological Sciences

    1995-04-01

    The primary-successional sere of a Hawaiian montane rain forest was inferred from an age sequence of eight closely located `a`a flows (clinker type lava); 8, 50, 140, ca. 300, ca. 400, ca. 1400, ca. 3000 and ca.9000 yr, on a windward slope of Mauna Loa, Hawaii. All study sites (0.2 ha each) were at 1120-1250 m a.s.l. with 4000 mm mean annual rainfall. The 400-yr, 1400-yr, and 9000-yr flows had younger volcanic ash deposits, while the others were pure lava. Comparisons of tree size and foliar nutrients suggested that ash increased the availability of nitrogen, and subsequently standing biomass. An Unweighted Pair Group Cluster Analysis on the samples (flows) using quantitative vascular species composition revealed that clusters were correlated with age regardless of the substrate types (pure lava vs. ash), and an indirect ordination on the samples suggested that the sequence of sample scores along axis 1 was perfectly correlated with the age sequence. Although ash deposits increased biomass, they did not affect the sequence of the successional sere. Both pubescent and glabrous varieties of Metrosideros polymorpha (Myrtaceae) dominated upper canopy layers on all flows {>=} 50 yr and {<=} 1400 yr, but the pubescent variety was replaced by the glabrous on the flows {>=} 3000 yr. Lower layers were dominated initially by a mated fern, Dicranopteris linearis, up to 300 yr, and subsequently by tree ferns, Cibotium spp., to 9000 yr. The cover of Cibotium declined sightly after 3000 yr, while other native herb and shrub species increased. 43 refs, 7 figs, 4 tabs

  17. Estimation of fog deposition on epiphytic bryophytes in a subtropical montane forest ecosystem in northeastern Taiwan

    Science.gov (United States)

    Chang, Shih-Chieh; Lai, I.-Ling; Wu, Jiunn-Tzong

    The fog meteorology, fog chemistry and fog deposition on epiphytic bryophytes were investigated from July 2000 to June 2001 in the Yuanyang Lake forest ecosystem. The elevation of the site ranges from 1650 to 2420 m, at which the high frequency of fog occurrence throughout the year has been thought to be of benefit to the establishment of the primary Taiwan yellow cypress forest [ Chamaecyparis obtusa var. formosana (Hayata) Rehder] and to the extensive growth of the epiphytic bryophytes. A weather station including a visibility sensor and an active fog collector was installed for fog meteorological and chemical study. The fog deposition rate on epiphytic bryophytes was estimated by measuring the increase rate in plant weight when exposed to fog. Average fog duration of 4.7 and 11.0 h per day was measured in summer months (June to August) and the rest of the year, respectively. November 2000 was the foggiest month in which the average fog duration reached 14.9 h per day. The ionic composition of fog water revealed that the area was less polluted than expected from literature data. The in situ exposure experiments done with the dominant epiphytic bryophytes showed an average fog deposition rate of 0.63 g H 2O g -1 d. w. h -1, which approximated 0.17 mm h -1 at the stand scale. The nutrient fluxes estimated for February 2001 showed that for all ions, more than 50% of the ecosystem input was through fog deposition. These results demonstrate the importance of epiphytic bryophytes and fog deposition in nutrient cycling of this subtropical montane forest ecosystem. The incorporation of fog study in the long-term ecosystem research projects is necessary in this area.

  18. Seed predation, disease and germination on landslides in Neotropical lower montane wet forest

    Energy Technology Data Exchange (ETDEWEB)

    Myster, R.W. [Puerto Rico Univ., San Juan (Puerto Rico). Inst. for Tropical Ecosystem Studies

    1997-02-01

    Seed mortality (caused by predators and pathogens) and germination were compared between Puerto Rico and Costa Rica on landslides in lower montane wet forest. Seeds of six common species on five Puerto Rican landslides and four common species on two Costa Rican landslides were used with a Cecropia species and a Gonzalagunia species included at both sites. In the Puerto Rican experiments Cecropia schreberiana was the only species to show significant seed predation (which was due to insects), pathogens grew from all species and fewer seeds were lost to predators than pathogens. Also in Puerto Rico mean germination across all species was 57% before dispersal (filled seeds collected while still on the tree) and 71% after, with Phytolacca rivinoides seeds germinating most abundantly, followed in descending order by Ocotea leucoxylon, Cecropia spec., Miconia racemosa, Palicourea riparia and Gonzalagunia spicata. In the Costa Rican experiments three species had significant predation: Cecropia polyphlebia and Urera caracasana (both due to insects) and Witheringia coccoloboides (due to mammals); pathogenic disease caused more seed loss than predation, and germination was high (61% pre-dispersal, 69% post-dispersal). Similarities between these island and mainland sites included (1) percentage of seeds lost to predation and percentage lost to pathogens (all in the 5-15% range), (2) generalist pathogens which claimed more seeds than predators and (3) majority germination with a general increase after dispersal. Finally sites were dissimilar only in the number of species with significant predation loss and whether it was by insects or mammals, casting doubt on the traditional island/mainland dichotomy. 62 refs, 3 figs, 2 tabs

  19. Coupling channel hydro-morphodynamics and fish spawning habitat in a forested montane stream

    Science.gov (United States)

    Cienciala, P.; Hassan, M. A.

    2011-12-01

    In this paper we couple a hydrodynamic model with field data to investigate channel dynamics and spawning habitat potential for small-bodied salmonids in coarse-bed streams in British Columbia. We studied four reaches of East Creek, a small montane stream near Vancouver, BC, which display rapid (plane bed) and riffle-pool morphologies and provide habitat for a population of resident coastal cutthroat trout. Repeated channel surveys were conducted to obtain detailed information on channel topography and dynamics; net change in bed elevation between successive surveys was utilized as an index of scour and fill. Extensive bed surface sampling and low altitude vertical imagery were used in order to investigate bed surface texture and structures and to identify suitable spawning substrate patches. A 2-D hydrodynamic model, FaSTMECH (within MultiDimensional Surface Water Modeling System interface), was calibrated using field data and applied to simulate the spatial pattern of bed shear stress during a bankfull flow event. During small-to-intermediate floods significant bed scour, deeper than the estimated egg burial depth, occurred on a small proportion of bed area, in well-defined zones associated with obstacles such as large woody debris. Usually, distinct depositional zones developed just downstream of the scour locations. The spatial distribution of forcing elements and modeled bed shear stress explained well the observed pattern of scour and fill. Suitable spawning gravel was very limited in the study sites, particularly in two upstream reaches, primarily due to the coarse nature of the bed. In summary, scour disturbance risk appears to be relatively low in coarse-bed channels, except during extreme flow events, and shortage of suitable spawning substrate may be more important for small-bodied salmonids. This study demonstrates that coupling of hydro-morphodynamic and ecological data can provide a useful tool in fish habitat assessment and restoration.

  20. 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.

  1. Tropical montane cloud forests: current threats and opportunities for their conservation and sustainable management in Mexico.

    Science.gov (United States)

    Toledo-Aceves, Tarin; Meave, Jorge A; González-Espinosa, Mario; Ramírez-Marcial, Neptalí

    2011-03-01

    Tropical montane cloud forests (TMCF) are among the most threatened ecosystems globally in spite of their high strategic value for sustainable development due to the key role played by these forests in hydrological cycle maintenance and as reservoirs of endemic biodiversity. Resources for effective conservation and management programs are rarely sufficient, and criteria must be applied to prioritize TMCF for conservation action. This paper reports a priority analysis of the 13 main regions of TMCF distribution in Mexico, based on four criteria: (1) forest quality, (2) threats to forest permanence, (3) threats to forest integrity, and (4) opportunities for conservation. Due to the diverse socio-environmental conditions of the local communities living in Mexican TMCF regions, their associated social characteristics were also evaluated to provide a background for the planning of conservation actions. A set of indicators was defined for the measurement of each criterion. To assign priority values for subregions within each main region, an international team of 40 participants evaluated all the indicators using multicriteria decision-making analysis. This procedure enabled the identification of 15 subregions of critical priority, 17 of high priority, and 10 of medium priority; three more were not analysed due to lack of information. The evaluation revealed a number of subjects that had hitherto been undetected and that may prove useful for prioritization efforts in other regions where TMCF is similarly documented and faces equally severe threats. Based on this analysis, key recommendations are outlined to advance conservation objectives in those TMCF areas that are subjected to high pressure on forest resources. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. 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.

  3. Transport and Transformation of Dissolved Organic Matter in Soil Interstitial Water Across Forested, Montane Hillslopes

    Science.gov (United States)

    Burns, M. A.; McKnight, D. M.; Gabor, R. S.; Brooks, P. D.; Barnard, H. R.

    2013-12-01

    Dissolved organic matter (DOM) is a ubiquitous mixture of compounds formed from the degradation of both terrestrial and microbial material. The abundance and composition of the DOM present in stream water is important to stream processes such as UV light attenuation, nutrient supply and metal sorption. However, an excess of DOM can cause reactions with chlorination compounds at drinking water treatment plants, creating potentially harmful disinfection byproducts. Currently, little is known regarding the influence of soil interstitial water on stream DOM composition. In this study, we explore the role of interstitial water on DOM transport and transformation from the hillslope to the stream in a montane catchment within the Boulder Creek Critical Zone Observatory in Colorado. We installed a suite of tension lysimeters located within the rooting zone across representative north- and south-facing slopes. Interstitial water and stream samples were collected daily for approximately seven weeks during the 2013 spring snow melt period and analyzed for DOM composition using fluorescence spectroscopy. To date, we have used fluorescence index (FI) to evaluate differences between microbial and terrestrial DOM inputs and humification index (HIX) to assess degree of humification undergone by the DOM. Preliminary results indicate that FI was significantly correlated with hillslope aspect (pwater inputs into the stream during snowmelt. These preliminary results suggest that changes in DOM composition through the catchment during snowmelt can be linked to hydrologic transport. Further site specific model development will reveal explicit changes in the DOM chemistry and will increase our understanding of fundamental nutrient cycling processes at the hillslope to catchment scale.

  4. Green-tailed Towhee response to prescribed fire in montane shrubland

    Science.gov (United States)

    Jehle, G.; Savidge, J.A.; Kotliar, N.B.

    2006-01-01

    Fire alters the structure and composition of shrublands and affects habitat quality for the associated avifauna. Because shrubland ecosystems have been greatly reduced from their original extent in western North America and fire is increasingly being used to manage these landscapes, a better understanding of how fire affects the associated vegetation and wildlife is imperative. We evaluated the response of Green-tailed Towhees (Pipilo chlorurus) to prescribed fire in the montane shrublands of Rocky Mountain National Park, Colorado during 2002 and 2003. Three to five years following prescribed burning, Green-tailed Towhee density and shrub cover were generally higher in unburned areas. Nests (n = 179) were located in unburned vegetation; within burned sites, all nests were in remnant patches. Green-tailed Towhee nest survival was 57% (95% CI = 49%-65%) across the two years of the study. More than half of the nests were in common juniper (Juniperus communis) shrubs, and nest survival was higher for nests in junipers than those in other shrub species. Daily nest survival rates were lower at the site with the highest density of towhees and declined over the breeding season. With regard to shrub cover, opposite trends were observed for nest-site selection and nest survival: nest plots had greater shrub cover than non-nest plots, but nest survival decreased with increasing shrub cover. Because shrub cover affects towhee density and nest survival in conflicting ways, fire management at Rocky Mountain National Park alters both habitat availability and suitability for Green-tailed Towhees. ?? The Cooper Ornithological Society 2006.

  5. Patterns of mortality in a montane mixed-conifer forest in San Diego County, California.

    Science.gov (United States)

    Freeman, Mary Pyott; Stow, Douglas A; An, Li

    2017-07-17

    We examine spatial patterns of conifer tree mortality and their changes over time for the montane mixed-conifer forests of San Diego County. These forest areas have recently experienced extensive tree mortality due to multiple factors. A spatial contextual image processing approach was utilized with high spatial resolution digital airborne imagery to map dead trees for the years 1997, 2000, 2002, and 2005 for three study areas: Palomar, Volcan, and Laguna mountains. Plot-based fieldwork was conducted to further assess mortality patterns. Mean mortality remained static from 1997 to 2002 (4, 2.2, and 4.2 trees ha(-1) for Palomar, Volcan, and Laguna) and then increased by 2005 to 10.3, 9.7 and 5.2 trees ha(-1) , respectively. The increase in mortality between 2002 and 2005 represents the temporal pattern of a discrete disturbance event, attributable to the 2002-2003 drought. Dead trees are significantly clustered for all dates, based on spatial cluster analysis, indicating that they form distinct groups, as opposed to spatially random single dead trees. Other tests indicate no directional shift or spread of mortality over time, but rather an increase in density. While general temporal and spatial mortality processes are uniform across all study areas, the plot-based species and quantity distribution of mortality, and diameter distributions of dead versus living trees, vary by study area. The results of this study improve our understanding of stand- to landscape-level forest structure and dynamics, particularly by examining them from the multiple perspectives of field and remotely sensed data. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  6. 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; Bosch, Jaime

    2016-01-01

    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’. PMID:28080980

  7. Can nutrients alone shift a sedge meadow towards dominance by the invasive Typha × glauca

    Science.gov (United States)

    Woo, Isa; Zedler, Joy B.

    2002-01-01

    Where wetlands receive urban runoff, Typha spp. and other invasive plants often displace the native vegetation. We tested the ability of nutrients (N and P) to increase vegetative growth of T. × glauca(a hybrid of T. latifolia and T. angustifolia). In the greenhouse, 17 treatments revealed that T. × glauca required both N and P for growth, and total leaf length was most stimulated where a higher proportion of P was added (7N∶1P vs. 14N∶1P, with N constant and P changed), regardless of concentration (the High treatment was 4× the Low treatment). In Gardner Marsh (Madison, Wisconsin, USA), we set up 28 plots (1×6 m) that bisected the boundary between sedge meadow (graminoids) and T. × glauca, and we added a common lawn fertilizer (9N∶1P∶4K) at high (62.5 g/m2), medium (31.3 g/m2), low (15.6 g/m2), and control (0 g/m2) rates on five dates, with n=7 plots/treatment. After one growing season, fertilizer addition increased T. × glauca ramet density, height, and biomass, especially where the sedge meadow graminoids were initially dominant. Aboveground biomass of T. × glauca in the high nutrient addition treatment (1029±256.1 g/m2) was more than double that for control plots (431±80.52 g/m2) overall, with the greatest percent increase in sedge meadow subplots. In contrast, native graminoids (mostly Carex spp.) did not respond to treatment, either in biomass or percent cover. Typha × glauca allocated nutrients to both growth and storage, as indicated by higher N and P concentrations in leaves, shoot bases, and rhizomes in plots with high nutrient addition. Because fertilizing the marsh enhanced the shoot growth of T. × glauca but not native graminoids, and because the 7N∶1P treatment stimulated growth in the greenhouse, we suggest that wetland managers focus on reducing P inflows to urban wetlands. Fertilizer additions below those recommended by the manufacturer for new lawns (5× that of our highest treatment) should be more

  8. 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.

  9. Cattail invasion of sedge/grass meadows in Lake Ontario: Photointerpretation analysis of sixteen wetlands over five decades

    Science.gov (United States)

    Wilcox, D.A.; Kowalski, K.P.; Hoare, H.L.; Carlson, M.L.; Morgan, H.N.

    2008-01-01

    Photointerpretation studies were conducted to evaluate vegetation changes in wetlands of Lake Ontario and the upper St. Lawrence River associated with regulation of water levels since about 1960. The studies used photographs from 16 sites (four each from drowned river mouth, barrier beach, open embayment, and protected embayment wetlands) and spanned a period from the 1950s to 2001 at roughly decadal intervals. Meadow marsh was the most prominent vegetation type in most wetlands in the late 1950s when water levels had declined following high lake levels in the early 1950s. Meadow marsh increased at some sites in the mid-1960s in response to low lake levels and decreased at all sites in the late 1970s following a period of high lake levels. Typha increased at nearly all sites, except wave-exposed open embayments, in the 1970s. Meadow marsh continued to decrease and Typha to increase at most sites during sustained higher lake levels through the 1980s, 1990s, and into 2001. Most vegetation changes could be correlated with lake-level changes and with life-history strategies and physiological tolerances to water depth of prominent taxa. Analyses of GIS coverages demonstrated that much of the Typha invasion was landward into meadow marsh, largely by Typha x glauca. Lesser expansion toward open water included both T. x glauca and T. angustifolia. Although many models focus on the seed bank as a key component of vegetative change in wetlands, our results suggest that canopy-dominating, moisture-requiring Typha was able to invade meadow marsh at higher elevations because sustained higher lake levels allowed it to survive and overtake sedges and grasses that can tolerate periods of drier soil conditions.

  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. 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

    Introduction The Oregon spotted frog (Rana pretiosa) is a highly aquatic frog that has been extirpated from a large portion of its historic range in the Pacific Northwest, and remaining populations are reduced and isolated (Hayes 1997, Pearl and Hayes 2005). Loss and alteration of marsh habitat, predation and competition from exotic fish and bullfrogs, and degraded water quality from agriculture and livestock grazing are implicated in their decline (Hayes 1997, Pearl and Hayes 2005). In 2001, an interagency team translocated a population of frogs from a site that was to be eliminated by the renovation of the dam impounding Wickiup Reservoir, to newly created ponds at Dilman Meadow (121i?? 39' 52" W, 43i?? 41' 58" N), 2.5 km from the original site in central Oregon, USA. We monitored Oregon spotted frog demography and movements at Dilman Meadow for > 4 yr to assess the efficacy of these mitigation efforts, determine metrics for long-term monitoring, and inform future management at the site. More broadly, many aspects of Oregon spotted frog life history are poorly known, so understanding demography and movement patterns is likely to be useful in its conservation. Although wildlife translocations have been attempted extensively as conservation means, few such projects have been sufficiently monitored for demographic rates to understand the causes for the translocation's success or failure (Dodd and Seigel 1991). Our objective here is to document demographic and movement patterns in the population of Oregon spotted frog at Dilman Meadow so that this information will be available to guide management decisions. To better evaluate amphibian population responses to management actions it is important to consider the contribution of each life history stage and both genders to the balance of reproduction and mortality. Population growth or contraction occurs as a complicated function of the probability of breeding, fecundity, and survival during multiple life history stages

  12. Modelling of Energy Flow, Rotational Grazing and Potential Productivity in an Alpine Meadow Grazing Ecosystem

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    An eight-compartment model of the energy dynamics of an alpine meadow-sheep grazing ecosystem was proposed based on SHIYOMI's system approach. The compartments were the above-ground plant portion, the underground live portion including roots, the underground dead portion including roots, the above-ground litter Ⅰ (degradable portion), the above-ground litter Ⅱ (undegradable portion), the sheep intake, the sheep liveweight, and the faeces. Energy flows between the eight compartments were described by eight simultaneous differential equations. All parameters in the model were determined from paddock experiments.The model was designed to provide a practical method for estimating the effects of the number of rotational grazing subplots, grazing period, and grazing pressure on the performance of grazing systems for perennial alpine meadow pasture. The model provides at least 28 different attributes for characterizing the performance of the grazing system. Analyses of 270 simulated rotational grazing systems of summer-autumn meadow pasture (grazing from 1st June to 30 October each year) provided an inference base to support two recommendations concerning management variables. First, with a three-paddock, 29-day grazing period and 30.14kJ·m-2·day-1 grazing pressure scheme, the system has the highest total grazing intake, 4250.44 kJ·m-2, during the grazing season. Secondly, with a three-paddock, 7-day grazing period and 28.89kJ·m-2·day-1 grazing pressure scheme, the accumulated graze is 4073.34kJ*m-2.The potential productivity of the alpine meadow under grazing is defined in this paper as the maximal dry biomass of herbage grazed by the grazing animals over the whole growing season. It has been analysed by applying optimal control theory to the model. The productivity is regarded as the objective function to be maximized through optimization of the time course of the grazing pressure, the control variable. The results show that: (1) under constant grazing pressure

  13. 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.

  14. THE INFLUENCE OF NITROGEN FERTILIZATION APPLIED IN DIFFERENT DOSES ON FODDER QUALITY OF MEADOW SWARD

    Directory of Open Access Journals (Sweden)

    Kazimierz Jankowski

    2013-07-01

    Full Text Available The experiment was organized in four replicants in arrangement split-plot with plots having a surface equal 9 m2. The basic fertilization was applied under the first regrowth. It was a mixture of unary fertilizers (ammonium nitrate, superphosphate, potassic salt or polifoska. One form of supplementary fertilization was applied under the second and third regrowth. It was the stable form of fertilizer applied to soil. This form of supplemented nitrogen gave respectively: 50 kg N·ha-l; 80 kg N·ha-l; 110 kg N·ha-1 per each moving. During the vegetation season three movings were harvested. From each movings the sampIes of green matter were taken for chemical analyses, i.e. total protein content, soluble carbohydrates and net energy (NEL. The obtained results showed large differences in fodder quality of the meadow sward fertilized with three doses of nitrogen.

  15. 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

    silage. The methane productivity from pretreated meadow grass silage, harvested at fall (late cut), was further examined in a co-digestion process with three different types of livestock manure (mink, poultry, and cattle). The silage was co-digested with manure in five different manure/silage mixing...... 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...... of the co-digestion mixture were found to be the key parameters for an improved biomethanation process....

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

    DEFF Research Database (Denmark)

    Schmidt, N.M.; Olsen, H.; Bildsøe, M.

    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. Generally......, grazing livestock had a negative effect on the peak biomass of small mammals, and the negative effect increased with grazing intensity, irrespective of whether pens were grazed by cattle or by sheep. More detailed analyses, however, revealed that an intermediate grazing intensity (approximately 400 kg...... ha-1 as maximum livestock biomass) actually seemed to benefit small mammals. This grazing intensity generally held small mammal biomasses and field vole population sizes that were similar to or larger than those on the ungrazed control, and markedly larger than those on the more heavily grazed pens...

  17. Case Study: Mobile Photovoltaic System at Bechler Meadows Ranger Station, Yellowstone National Park (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2014-03-01

    The mobile PV/generator hybrid system deployed at Bechler Meadows provides a number of advantages. It reduces on-site air emissions from the generator. Batteries allow the generator to operate only at its rated power, reducing run-time and fuel consumption. Energy provided by the solar array reduces fuel consumption and run-time of the generator. The generator is off for most hours providing peace and quiet at the site. Maintenance trips from Mammoth Hot Springs to the remote site are reduced. The frequency of intrusive fuel deliveries to the pristine site is reduced. And the system gives rangers a chance to interpret Green Park values to the visiting public. As an added bonus, the system provides all these benefits at a lower cost than the basecase of using only a propane-fueled generator, reducing life cycle cost by about 26%.

  18. Case Study: Mobile Photovoltaic System at Bechler Meadows Ranger Station, Yellowstone National Park

    Energy Technology Data Exchange (ETDEWEB)

    Andy Walker

    2014-03-05

    The mobile PV/generator hybrid system deployed at Bechler Meadows provides a number of advantages. It reduces on-site air emissions from the generator. Batteries allow the generator to operate only at its rated power, reducing run-time and fuel consumption. Energy provided by the solar array reduces fuel consumption and run-time of the generator. The generator is off for most hours providing peace and quiet at the site. Maintenance trips from Mammoth Hot Springs to the remote site are reduced. The frequency of intrusive fuel deliveries to the pristine site is reduced. And the system gives rangers a chance to interpret Green Park values to the visiting public. As an added bonus, the system provides all these benefits at a lower cost than the basecase of using only a propane-fueled generator, reducing life cycle cost by about 26%.

  19. 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

  20. The Geographic Distribution of a Tropical Montane Bird Is Limited by a Tree: Acorn Woodpeckers (Melanerpes formicivorus) and Colombian Oaks (Quercus humboldtii) in the Northern Andes.

    Science.gov (United States)

    Freeman, Benjamin G; Mason, Nicholas A

    2015-01-01

    Species distributions are limited by a complex array of abiotic and biotic factors. In general, abiotic (climatic) factors are thought to explain species' broad geographic distributions, while biotic factors regulate species' abundance patterns at local scales. We used species distribution models to test the hypothesis that a biotic interaction with a tree, the Colombian oak (Quercus humboldtii), limits the broad-scale distribution of the Acorn Woodpecker (Melanerpes formicivorus) in the Northern Andes of South America. North American populations of Acorn Woodpeckers consume acorns from Quercus oaks and are limited by the presence of Quercus oaks. However, Acorn Woodpeckers in the Northern Andes seldom consume Colombian oak acorns (though may regularly drink sap from oak trees) and have been observed at sites without Colombian oaks, the sole species of Quercus found in South America. We found that climate-only models overpredicted Acorn Woodpecker distribution, suggesting that suitable abiotic conditions (e.g. in northern Ecuador) exist beyond the woodpecker's southern range margin. In contrast, models that incorporate Colombian oak presence outperformed climate-only models and more accurately predicted the location of the Acorn Woodpecker's southern range margin in southern Colombia. These findings support the hypothesis that a biotic interaction with Colombian oaks sets Acorn Woodpecker's broad-scale geographic limit in South America, probably because Acorn Woodpeckers rely on Colombian oaks as a food resource (possibly for the oak's sap rather than for acorns). Although empirical examples of particular plants limiting tropical birds' distributions are scarce, we predict that similar biotic interactions may play an important role in structuring the geographic distributions of many species of tropical montane birds with specialized foraging behavior.

  1. 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

  2. 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.)

  3. Comparative toxicity of acephate in laboratory mice, white-footed mice, and meadow voles

    Science.gov (United States)

    Rattner, B.A.; Hoffman, D.J.

    1984-01-01

    The LD50 (95% confidence limits) of the organophosphorus insecticide acephate was estimated to be 351, 380, and 321 mg/kg (295?416, 280?516, and 266?388 mg/kg) for CD-1 laboratory mice (Mus musculus), white-footed mice (Peromyscus leucopus noveboracensis), and meadow voles (Microtus pennsylvanicus), respectively. In a second study, these species were provided mash containing 0, 25, 100, and 400 ppm acephate for five days. Brain and plasma cholinesterase activities were reduced in a dose-dependent manner to a similar extent in the three species (inhibition of brain acetyl-cholinesterase averaged for each species ranged from 13 to 22% at 25 ppm, 33 to 42% at 100 ppm, and 56 to 57% at 400 ppm). Mash intake, body or liver weight, plasma enzyme activities (alkaline phosphatase, alanine and aspartate aminotransferase), hepatic enzyme activities (aniline hydroxylase, 7-ethoxycoumarin O-deethylase, and glutathione S-transferase), and cytochrome content (P-450 and b5) were not affected by acephate ingestion, although values differed among species. In a third experiment, mice and voles received 400 ppm acephate for 5 days followed by untreated food for up to 2 weeks. Mean inhibition of brain acetylcholin-esterase for the three species ranged from 47 to 58% on day 5, but by days 12 and 19, activity had recovered to 66 to 76% and 81 to 88% of concurrent control values. These findings indicate that CD-1 laboratory mice, white-footed mice, and meadow voles are equally sensitive to acephate when maintained under uniform laboratory conditions. Several factors (e.g., behavior, food preference, habitat) could affect routes and degree of exposure in the field, thereby rendering some species of wild rodents ecologically more vulnerable to organophosphorus insecticides.

  4. Sediment carbon sink in low-density temperate eelgrass meadows (Baltic Sea)

    Science.gov (United States)

    Jankowska, Emilia; Michel, Loïc. N.; Zaborska, Agata; Włodarska-Kowalczuk, Maria

    2016-12-01

    Seagrass meadows are highly productive habitats that can act as "blue carbon sinks" in coastal ecosystems by facilitating sedimentation and trapping particles. However, the magnitude and occurrence of these effects may be species and density dependent. The present study is the first estimation of seagrass sediment carbon sink in the temperate Zostera marina beds in the Baltic Sea. Several descriptors of organic matter characteristics, along with possible organic matter sources in the sediment were compared at vegetated and unvegetated bottoms. The 210Pb dating of the sediment has been used for accumulation rate assessment. The photopigments and POC concentrations in sediments were higher in vegetated bottoms. The SIAR (Stable Isotopes in R) mixing model based on nitrogen and carbon stable isotope values, indicated that higher percentages of organic matter originated from seagrass production in vegetated sediments (40-45%) compared to unvegetated ones (5-21%). The carbon stock in the upper 10 cm of the vegetated sediments ranged from 50.2 ± 2.2 to 228.0 ± 11.6 (g m-2), whereas the annual C accumulation amount from 0.84 ± 0.2 to 3.85 ± 1.2 (g m-2 yr-1). Our study shows that even the relatively weakly developed vegetation of the small temperate seagrass species enhance organic carbon concentration in the sediments. Estimated carbon stock was much lower than those reported for most of the seagrass meadows elsewhere, and the carbon burial rate was the lowest ever reported. Evidently, the global calculations of sediment carbon stock should be reconsidered by taking into account density and species-related variability.

  5. 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.

  6. 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.

  7. 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.

  8. 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

    2014-03-25

    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.

  9. 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.

  10. 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.

  11. 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...

  12. 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...

  13. 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

  14. Land use change effects on runoff generation in a humid tropical montane cloud forest region

    Directory of Open Access Journals (Sweden)

    L. E. Muñoz-Villers

    2013-04-01

    Full Text Available While tropical montane cloud forests (TMCF provide critical hydrological services to downstream regions throughout much of the humid tropics, catchment hydrology and impacts associated with forest conversion in these ecosystems remain poorly understood. Here, we compare the annual, seasonal and event-scale streamflow patterns and runoff generation processes of three neighbouring headwater catchments in central Veracruz (eastern Mexico with similar pedological and geological characteristics, but different land cover: old-growth TMCF (MAT, 20 yr-old naturally regenerating TMCF (SEC and a heavily grazed pasture (PAS. We used a 2 yr record of high resolution rainfall and stream flow data (2008–2010 in combination with stable isotope and chemical tracer data collected for a series of storms during a 6-week period of increasing antecedent wetness (wetting-up cycle. Our results showed that annual and seasonal streamflow patterns of the MAT and SEC were similar. In contrast, the PAS showed a 10% higher mean annual streamflow, most likely because of a lower rainfall interception. During the wetting-up cycle, storm runoff ratios increased at all three catchments (from 11 to 54% for the MAT, 7 to 52% for the SEC and 3 to 59% for the PAS. With the increasing antecedent wetness, hydrograph separation analysis showed progressive increases of pre-event water contributions to total stormflow (from 35 to 99% in the MAT, 26 to 92% in the SEC and 64 to 97% in the PAS. At all three sites, rainfall-runoff responses were dominated by subsurface flow generation processes for the majority of storms. However, for the largest and most intense storm (typically occurring once every 2 yr, sampled under wet antecedent conditions, the event water contribution in the PAS (34% on average was much higher than in the forests (5% on average, indicating that rainfall infiltration capacity of the PAS was exceeded. This result suggests that despite the high permeability of the

  15. Seed germination of cirsium arvense and Lepidium latifolium: Implications for management of montane wetlands

    Science.gov (United States)

    Laubhan, M.K.; Shaffer, T.L.

    2006-01-01

    Cirsium arvense and Lepidium latifolium are species that can aggressively invade wetland margins and potentially reduce biodiversity and alter ecosystem function. Although expansion of these species primarily occurs via rhizomatous growth, seeds are thought to be important in initial establishment. We conducted this study to investigate differences in seed germination of C. arvense and L. latifolium in montane wetlands of Colorado and Wyoming, USA. We used germination chambers to simulate environmental conditions (photoperiod, day/night temperature) during three periods of the growing season at each site and evaluated seed germination in relation to three soil moisture levels and two soil depths. A combination of shallow (seed burial and wet conditions resulted in the greatest germination probability of C. arvense (x = 63.0%), 95% CI = 41.2-80.5%), whereas deep (2-3 cm) seed burial and saturated moisture conditions resulted in almost no germination (x?? = 0.3%, 95% CI = 0.1-1.3%). The maximum germination probability of 44.0% (CI = 28.1-61.4%) for L. latifolium also occurred in the shallow burial and wet treatment; however, only effects of seed burial were significant (P germination probability of deeply buried seeds was seeds. Our results suggest that each species has the ability to germinate at similar rates throughout the growing season and across a large portion of the moisture gradient. This suggests that management actions, including water-level manipulations, at any time during the growing season may stimulate germination. Although burial of seed to depths of 2-3 cm reduced the germination potential of both species, the use of mechanical implements may be problematic in established stands because new plants of both species easily sprout from root buds. Further, disturbance resulting from such actions diminishes the density and vigor of other plants already present, which may ultimately decrease the competitive resistance of the disturbed environment to

  16. 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

  17. Investigating drought vulnerability using stable water isotopes and tritium in a montane system

    Science.gov (United States)

    Thaw, Melissa; Visser, Ate; Deinhart, Amanda; Bibby, Richard; Everhart, Anthony; Sharp, Mike; Conklin, Martha

    2017-04-01

    We combined measurements of water stable isotopes (d18O and d2H) with measurements of tritium (3H) to track water from precipitation through the subsurface and vegetation. Our study examined drought vulnerability in terms of vegetation water sources and subsurface storage in two montane sites, seasonally, using stable isotopes and tritium. Relative proportions of evapotranspiration sources were determined using two-tracer (d18O and 3H), three component mixing models. The two sites, located in the Southern Sierra Critical Zone Observatory, California, USA, are Mediterranean in climate, straddling the rain-snow transition zone where the upper elevation site receives most of its precipitation as winter snow. Over the study period, summer 2015 followed four years of severe snow drought; summer 2016 followed a slightly below average winter. The lower elevation site experienced severe drought-induced tree mortality over this time. Preliminary results show severe snow drought conditions and summer precipitation affected the proportions of source water used by vegetation due to the ability of vegetation to change sources when new water became available. Both stable isotopes and tritium reflect seasonal shifts in vegetation water sources, as well as species vulnerability and tolerance to drought. Xylem water sampled from Abies concolor (white fir) and Arctostaphylos patula (manzanita) responded the most quickly to changes in available water sources compared to Pinus jeffreyi (Jeffrey pine) and Calocedrus decurrens (incense cedar). Abies concolor and Arctostaphylos patula responded more dramatically to summer soil evaporation by accessing summer rain and deep water sources more quickly. Abies concolor also responded more dramatically to changes in snowpack during winter. During severe drought conditions, Arctostaphylos's ability to tap into a wide range of water sources coincided with drought tolerance (100% survival rate), while mortality for Pinus ponderosa and Calocedrus

  18. Water balances of old-growth and regenerating montane cloud forests in central Veracruz, Mexico

    Science.gov (United States)

    Muñoz-Villers, L. E.; Holwerda, F.; Gómez-Cárdenas, M.; Equihua, M.; Asbjornsen, H.; Bruijnzeel, L. A.; Marín-Castro, B. E.; Tobón, C.

    2012-09-01

    SummaryThis paper compares the water budgets of two adjacent micro-catchments covered by mature (MAT) and 20-year-old secondary (SEC) lower montane cloud forests, respectively, in central Veracruz, Mexico over a 2-year period. Rainfall (P) and streamflow (Q) were measured continuously, whereas dry canopy evaporation (transpiration Et), wet canopy evaporation (rainfall interception I), and cloud water interception (CWI) were quantified using a combination of field measurements and modeling. Mean annual P was 3467 mm, of which typically 80% fell during the wet season (May-October). Fog interception occurred exclusively during the dry season (November-April), and was ⩽2% of annual P for both forests. Rainfall interception loss was dominated by post-event evaporation of intercepted water rather than by within-event evaporation. Therefore, the higher overall I (i.e. including CWI) by the MAT (16% of P vs. 8% for the SEC) reflects a higher canopy storage capacity, related in turn to higher leaf area index and greater epiphyte biomass. Annual Et totals derived from sapflow measurements were nearly equal for the MAT and SEC (˜790 mm each). Total annual water yield calculated as P minus (Et + I) was somewhat higher for the SEC (2441 mm) than for the MAT (2077 mm), and mainly reflects the difference in I. Mean annual Q was also higher for the SEC (1527 mm) than for the MAT (1338 mm), and consisted mostly of baseflow (˜90%). Baseflow recession rates were nearly equal between the two forests, as were stormflow coefficients (4% and 5% for MAT and SEC, respectively). The very low runoff response to rainfall is attributed to the high infiltration and water retention capacities of the volcanic soils throughout the ˜2 m deep profile. The water budget results indicate that ˜875 and 700 mm year-1 leave the SEC and MAT as deep groundwater leakage, which is considered plausible given the fractured geology in the study area. It is concluded that 20 years of natural regeneration

  19. Lake Roosevelt Fisheries Evaluation Program; Meadow Creek vs. Lake Whatcom Stock Kokanee Salmon Investigations in Lake Roosevelt, 2001 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    McLellan, Holly; Scholz, Allan

    2002-03-01

    Lake Roosevelt has been stocked with Lake Whatcom stock kokanee since 1989 with the primary objective of creating a self-sustaining recreational fishery. Due to low return numbers, it was hypothesized a stock of kokanee, native to the upper Columbia River, might perform better than the coastal Lake Whatcom strain. Kokanee from Meadow Creek, a tributary of Kootenay Lake, British Columbia were selected as an alternative stock. Matched pair releases of Lake Whatcom and Meadow Creek kokanee were made from Sherman Creek Hatchery in late June 2000 and repeated in 2001. Stock performance between Lake Whatcom and Meadow Creek kokanee was evaluated using three performance measures; (1) the number of returns to Sherman Creek, the primary egg collection facility, (2) the number of returns to other tributaries and (3) the number of returns to the creel. Kokanee were collected during five passes through the reservoir via electrofishing, which included 87 tributary mouths during the fall of 2000 and 2001. Chi-square analysis indicated age two Meadow Creek kokanee returned to Sherman Creek in significantly higher numbers when compared to the Whatcom stock in 2000 ({chi}{sup 2} = 736.6; d.f. = 1; P < 0.01) and 2001 ({chi}{sup 2} = 156.2; d.f. = 1; P < 0.01). Reservoir wide recoveries of age two kokanee had similar results in 2000 ({chi}{sup 2} = 735.3; d.f. = 1; P < 0.01) and 2001 ({chi}{sup 2} = 150.1; d.f. = 1; P < 0.01). Six Lake Whatcom and seven Meadow Creek three year olds were collected in 2001. The sample size of three year olds was too small for statistical analysis. No kokanee were collected during creel surveys in 2000, and two (age three kokanee) were collected in 2001. Neither of the hatchery kokanee collected were coded wire tagged, therefore stock could not be distinguished. After two years of monitoring, neither Meadow Creek or Lake Whatcom kokanee appear to be capable of providing a run of three-year-old spawners to sustain stocking efforts. The small number of

  20. U.S. Department of the Interior Fish and Wildlife Service : Environmental Assessment : Final (1/2011) for Proposed Hunting Plan for Crane Meadows National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The United States Fish and Wildlife Service is proposing to provide hunting opportunities on Crane Meadows National Wildlife Refuge in Little Falls, Minnesota that...