WorldWideScience

Sample records for studies lake forest

  1. White River National Forest Hanging Lake transportation and operations study

    Science.gov (United States)

    2017-05-01

    Hanging Lake is a recreation site located on land managed by the U.S. Forest Service (USFS) under the jurisdiction of the White River National Forests Eagle-Holy Cross Ranger District. Due to its increasing popularity over the past few years, the ...

  2. Isotopic study of mercury sources and transfer between a freshwater lake and adjacent forest food web

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Sae Yun, E-mail: saeyunk@umich.edu [Department of Earth and Environmental Sciences, University of Michigan, 1100 N. University Ave, Ann Arbor, MI 48109 (United States); Blum, Joel D. [Department of Earth and Environmental Sciences, University of Michigan, 1100 N. University Ave, Ann Arbor, MI 48109 (United States); Department of Ecology and Evolutionary Biology, University of Michigan, 830 N. University Ave, Ann Arbor, MI 48109 (United States); Nadelhoffer, Knute J. [Department of Ecology and Evolutionary Biology, University of Michigan, 830 N. University Ave, Ann Arbor, MI 48109 (United States); Timothy Dvonch, J. [Department of Environmental Health Sciences, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Tsui, Martin Tsz-Ki [Department of Biology, University of North Carolina at Greensboro, 321 McIver Street, Greensboro, NC 27402 (United States)

    2015-11-01

    Studies of monomethylmercury (MMHg) sources and biogeochemical pathways have been extensive in aquatic ecosystems, but limited in forest ecosystems. Increasing evidence suggests that there is significant mercury (Hg) exchange between aquatic and forest ecosystems. We use Hg stable isotope ratios (δ{sup 202}Hg and Δ{sup 199}Hg) to investigate the relative importance of MMHg sources and assess Hg transfer pathways between Douglas Lake and adjacent forests located at the University of Michigan Biological Station, USA. We characterize Hg isotopic compositions of basal resources and use linear regression of % MMHg versus δ{sup 202}Hg and Δ{sup 199}Hg to estimate Hg isotope values for inorganic mercury (IHg) and MMHg in the aquatic and adjacent forest food webs. In the aquatic ecosystem, we found that lake sediment represents a mixture of IHg pools deposited via watershed runoff and precipitation. The δ{sup 202}Hg and Δ{sup 199}Hg values estimated for IHg are consistent with other studies that measured forest floor in temperate forests. The Δ{sup 199}Hg value estimated for MMHg in the aquatic food web indicates that MMHg is subjected to ~ 20% photochemical degradation prior to bioaccumulation. In the forest ecosystem, we found a significant negative relationship between total Hg and δ{sup 202}Hg and Δ{sup 199}Hg of soil collected at multiple distances from the lakeshore and lake sediment. This suggests that IHg input from watershed runoff provides an important Hg transfer pathway between the forest and aquatic ecosystems. We measured Δ{sup 199}Hg values for high trophic level insects and compared these insects at multiple distances perpendicular to the lake shoreline. The Δ{sup 199}Hg values correspond to the % canopy cover suggesting that forest MMHg is subjected to varying extents of photochemical degradation and the extent may be controlled by sunlight. Our study demonstrates that the use of Hg isotopes adds important new insight into the relative

  3. Random forests as cumulative effects models: A case study of lakes and rivers in Muskoka, Canada.

    Science.gov (United States)

    Jones, F Chris; Plewes, Rachel; Murison, Lorna; MacDougall, Mark J; Sinclair, Sarah; Davies, Christie; Bailey, John L; Richardson, Murray; Gunn, John

    2017-10-01

    Cumulative effects assessment (CEA) - a type of environmental appraisal - lacks effective methods for modeling cumulative effects, evaluating indicators of ecosystem condition, and exploring the likely outcomes of development scenarios. Random forests are an extension of classification and regression trees, which model response variables by recursive partitioning. Random forests were used to model a series of candidate ecological indicators that described lakes and rivers from a case study watershed (The Muskoka River Watershed, Canada). Suitability of the candidate indicators for use in cumulative effects assessment and watershed monitoring was assessed according to how well they could be predicted from natural habitat features and how sensitive they were to human land-use. The best models explained 75% of the variation in a multivariate descriptor of lake benthic-macroinvertebrate community structure, and 76% of the variation in the conductivity of river water. Similar results were obtained by cross-validation. Several candidate indicators detected a simulated doubling of urban land-use in their catchments, and a few were able to detect a simulated doubling of agricultural land-use. The paper demonstrates that random forests can be used to describe the combined and singular effects of multiple stressors and natural environmental factors, and furthermore, that random forests can be used to evaluate the performance of monitoring indicators. The numerical methods presented are applicable to any ecosystem and indicator type, and therefore represent a step forward for CEA. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  4. Lake Lysevatten - A study of liming and reacidification effects in a forest lake ecosystem in southwestern Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, B.I.; Hultberg, H.

    1997-02-01

    Long-term monitoring (1973 to 1987) of acidification and liming effects to a lake ecosystem is reported in this study. The liming intervention of Lake Lysevatten in spring 1974 resulted in neutralisation of lake water and positive alkalinity. Invasion and population expansion of new species started and proceeded for several years. Following the neutralisation Sphagnum was almost eradicated. The restocking with fish changed the predator-prey interactions, and the community composition gradually approached what would be expected to be within the normal range for an unacidified lake. Early signs of reacidification were: The appearance of filamentous algae; Decreased condition of Brown trout (Salmo trutta) caused by increased aluminium concentrations in connection with an acid event; Enhanced growth of Sphagnum surviving on profundal bottoms. Progressive reacidification to Ph 5.0 resulted in accelerated growth of Mougeotia reaching nuisance level. If implemented, liming should be prolonged by reinterventions before alkalinity and pH decrease to much. A stable circumneutral pH is a prerequisite to provide the timescale necessary for invasion and population growth of organisms with low dispersal capacity. Furthermore, the most sensitive organisms will be adversely affected already at pH-values around six. Extensive reacidification should by all means be prevented as development of a destabilized lake community could react rather unpredictably. 168 refs, 80 figs, 26 tabs

  5. Experimental study of heat and momentum exchange between a forest lake and the atmosphere in winter

    Science.gov (United States)

    Barskov, K. V.; Chernyshev, R. V.; Stepanenko, V. M.; Repina, I. A.; Artamonov, A. Yu; Guseva, S. P.; Gavrikov, A. V.

    2017-11-01

    The article presents the results of an experimental study of turbulent heat exchange between the surface of a frozen lake surrounded by forest and the atmospheric boundary layer. Heat and momentum fluxes were measured at three levels by an eddy covariance (EC) technique. Additionally, the heat fluxes were estimated by a surface energy balance method using a temperature profile measured in the snow cover and net longwave and shortwave radiation. The results of the measurements show that the eddy covariance fluxes correlate well with those obtained by the surface energy balance method, with a tendency of underestimation. The presence of wind-shear effects at treetop height demonstrated recently in a Large Eddy Simulation (LES) [3] was supported in our measurements by the fact that the momentum flux increased with height from the surface. The negative sensible heat flux increased with height most of the time. We suggest that this phenomenon may partially be caused by the high negative heat fluxes above the surface formed when warm advection occurs at altitudes of ~100 m. During the warm advection events, Monin-Obukhov similarity theory (MOST) fails to reproduce the sharp increase of the negative heat flux at the surface layer. Beyond the warm advection events, the MOST calculations agree well with the EC fluxes, however, with some systematic underestimation bias.

  6. Mechanisms influencing changes in lake area in Alaskan boreal forest

    Science.gov (United States)

    Roach, Jennifer K.; Griffith, Brad; Verbyla, David; Jones, Jeremy B.

    2011-01-01

    During the past ∼50 years, the number and area of lakes have declined in several regions in boreal forests. However, there has been substantial finer-scale heterogeneity; some lakes decreased in area, some showed no trend, and others increased. The objective of this study was to identify the primary mechanisms underlying heterogeneous trends in closed-basin lake area. Eight lake characteristics (δ18O, electrical conductivity, surface : volume index, bank slope, floating mat width, peat depth, thaw depth at shoreline, and thaw depth at the forest boundary) were compared for 15 lake pairs in Alaskan boreal forest where one lake had decreased in area since ∼1950, and the other had not. Mean differences in characteristics between paired lakes were used to identify the most likely of nine mechanistic scenarios that combined three potential mechanisms for decreasing lake area (talik drainage, surface water evaporation, and terrestrialization) with three potential mechanisms for nondecreasing lake area (subpermafrost groundwater recharge through an open talik, stable permafrost, and thermokarst). A priori expectations of the direction of mean differences between decreasing and nondecreasing paired lakes were generated for each scenario. Decreasing lakes had significantly greater electrical conductivity, greater surface : volume indices, shallower bank slopes, wider floating mats, greater peat depths, and shallower thaw depths at the forest boundary. These results indicated that the most likely scenario was terrestrialization as the mechanism for lake area reduction combined with thermokarst as the mechanism for nondecreasing lake area. Terrestrialization and thermokarst may have been enhanced by recent warming which has both accelerated permafrost thawing and lengthened the growing season, thereby increasing plant growth, floating mat encroachment, transpiration rates, and the accumulation of organic matter in lake basins. The transition to peatlands associated

  7. 77 FR 18997 - Rim Lakes Forest Restoration Project; Apache-Sitgreavese National Forest, Black Mesa Ranger...

    Science.gov (United States)

    2012-03-29

    ... DEPARTMENT OF AGRICULTURE Forest Service Rim Lakes Forest Restoration Project; Apache-Sitgreavese... intends to conserve and restore the Rim Lakes Project Area to make--over time--the forest ecosystem more... concerns and contentions. The proposed Rim Lakes Forest Restoration Project is subject to the HFRA pre...

  8. Impact of forest harvesting on water quality and fluorescence characteristics of dissolved organic matter in Eastern Canadian Boreal Shield lakes

    OpenAIRE

    P. Glaz; J.-P. Gagné; P. Archambault; P. Sirois; C. Nozais

    2015-01-01

    Forestry activities in the Canadian Boreal region have increased in the last decades, raising concerns about their potential impact on aquatic ecosystems. Water quality and fluorescence characteristics of dissolved organic matter (DOM) were measured over a three-year period in eight Eastern Boreal Shield lakes: four lakes were studied before, one and two years after forest harvesting (perturbed lakes) and compared with four undisturbed reference lakes (unperturbed lakes) sample...

  9. Detecting Precontact Anthropogenic Microtopographic Features in a Forested Landscape with Lidar: A Case Study from the Upper Great Lakes Region, AD 1000-1600.

    Science.gov (United States)

    Howey, Meghan C L; Sullivan, Franklin B; Tallant, Jason; Kopple, Robert Vande; Palace, Michael W

    2016-01-01

    Forested settings present challenges for understanding the full extent of past human landscape modifications. Field-based archaeological reconnaissance in forests is low-efficiency and most remote sensing techniques are of limited utility, and together, this means many past sites and features in forests are unknown. Archaeologists have increasingly used light detection and ranging (lidar), a remote sensing tool that uses pulses of light to measure reflecting surfaces at high spatial resolution, to address these limitations. Archaeology studies using lidar have made significant progress identifying permanent structures built by large-scale complex agriculturalist societies. Largely unaccounted for, however, are numerous small and more practical modifications of landscapes by smaller-scale societies. Here we show these may also be detectable with lidar by identifying remnants of food storage pits (cache pits) created by mobile hunter-gatherers in the upper Great Lakes during Late Precontact (ca. AD 1000-1600) that now only exist as subtle microtopographic features. Years of intensive field survey identified 69 cache pit groups between two inland lakes in northern Michigan, almost all of which were located within ~500 m of a lakeshore. Applying a novel series of image processing techniques and statistical analyses to a high spatial resolution DTM we created from commercial-grade lidar, our detection routine identified 139 high potential cache pit clusters. These included most of the previously known clusters as well as several unknown clusters located >1500 m from either lakeshore, much further from lakeshores than all previously identified cultural sites. Food storage is understood to have emerged regionally as a risk-buffering strategy after AD 1000 but our results indicate the current record of hunter-gatherer cache pit food storage is markedly incomplete and this practice and its associated impact on the landscape may be greater than anticipated. Our study also

  10. Fire effects on soils in Lake States forests: A compilation of published research to facilitate long-term investigations

    Science.gov (United States)

    Jessica Miesel; P. Goebel; R. Corace; David Hix; Randall Kolka; Brian Palik; David. Mladenoff

    2012-01-01

    Fire-adapted forests of the Lake States region are poorly studied relative to those of the western and southeastern United States and our knowledge base of regional short- and long-term fire effects on soils is limited. We compiled and assessed the body of literature addressing fire effects on soils in Lake States forests to facilitate the re-measurement of previous...

  11. The impact of acid deposition and forest harvesting on lakes and their forested catchments in south central Ontario: a critical loads approach

    Directory of Open Access Journals (Sweden)

    S. A. Watmough

    2002-01-01

    Full Text Available The impact of acid deposition and tree harvesting on three lakes and their representative sub-catchments in the Muskoka-Haliburton region of south-central Ontario was assessed using a critical loads approach. As nitrogen dynamics in forest soils are complex and poorly understood, for simplicity and to allow comparison among lakes and their catchments, CLs (A for both lakes and forest soils were calculated assuming that nitrate leaching from catchments will not change over time (i.e. a best case scenario. In addition, because soils in the region are shallow, base cation weathering rates for the representative sub-catchments were calculated for the entire soil profile and these estimates were also used to calculate critical loads for the lakes. These results were compared with critical loads obtained by the Steady State Water Chemistry (SSWC model. Using the SSWC model, critical loads for lakes were between 7 and 19 meq m-2yr-1 higher than those obtained from soil measurements. Lakes and forests are much more sensitive to acid deposition if forests are harvested, but two acid-sensitive lakes had much lower critical loads than their respective forested sub-catchments implying that acceptable acid deposition levels should be dictated by the most acid-sensitive lakes in the region. Under conditions that assume harvesting, the CL (A is exceeded at two of the three lakes and five of the six sub-catchments assessed in this study. However, sulphate export from catchments greatly exceeds input in bulk deposition and, to prevent lakes from falling below the critical chemical limit, sulphate inputs to lakes must be reduced by between 37% and 92% if forests are harvested. Similarly, sulphate leaching from forested catchments that are harvested must be reduced by between 16 and 79% to prevent the ANC of water draining the rooting zone from falling below 0 μeq l-1. These calculations assume that extremely low calcium leaching losses (9–27 μeq l-1 from

  12. Impact of forest disturbance on the pollen influx in lake sediments during the last century.

    Science.gov (United States)

    Koff; Punning; Kangur

    2000-08-01

    The pollen accumulation rates of four lakes in different regions of Estonia were estimated in order to study the relationship between pollen influx and the character and intensity of disturbances in the pollen catchment area. The pollen influx data obtained are in accordance with model calculations on the size of the pollen source areas. The influx of arboreal pollen and that of the dominant taxa (mainly Pinus) in the lakes investigated shows that, in the case of small lakes (area 3-6ha) in a forested landscapes, the bulk of the pollen originates from an area within 100-200m around the lake. The distribution patterns of influx from two lakes situated close to each other but at different distances from forest fires show that past disturbances can be reliably detected when the disturbance occurred in the immediate vicinity of the lake and at least 25% of the local pollen source area was involved. In the case of a large lake (137ha) only fires embracing thousands of hectares can be detected in the pollen diagrams.

  13. Littoral macroinvertebrates of acidified lakes in the Bohemian Forest

    Czech Academy of Sciences Publication Activity Database

    Ungermanová, L.; Kolaříková, K.; Stuchlík, E.; Senoo, T.; Horecký, J.; Kopáček, Jiří; Chvojka, P.; Tátosová, J.; Bitušík, P.; Fjellheim, A.

    2014-01-01

    Roč. 69, č. 9 (2014), s. 1190-1201 ISSN 0006-3088 R&D Projects: GA ČR(CZ) GA526/09/0567; GA ČR(CZ) GA206/07/1200 Grant - others:EC(XE) EURO-LIMPACS GOCE-CT-2003-505540 Institutional support: RVO:60077344 Keywords : lakes * macroinvertebrates * acidification * recovery * forest catchment Subject RIV: DJ - Water Pollution ; Quality Impact factor: 0.827, year: 2014

  14. Bioavailability of cesium radionuclides in prealpine forests and lakes

    International Nuclear Information System (INIS)

    Klemt, E.; Drissner, J.; Fluegel, V.; Kaminski, S.; Walser, M.; Zibold, G.; Lindner, G.

    1996-01-01

    In forests of southwest Germany radiocesium from Chernobyl is still accumulated in the organic layers of the soil. This radiocesium is available for the biosphere showing variations of the transfer factor of 3 orders of magnitude due to variations of thickness, degree of decomposition, and pH of the organic soil horizons as exemplified by measurements of the contamination of soil, plants and 5600 roe deer. Bioavailability of radiocesium seems to be mediated by mycorrhiza fungi. In lakes the persistence of elevated levels of dissolved radiocesium in the water and in the fish population is found - as in forest soil - to be due to the reversible binding of radiocesium to organic matter in sediments and in watersheds and its redissolution as shown for Vorsee, a shallow eutrophic lake. A totally different behaviour is observed in Lake Constance, a deep mesotrophic hard-water lake, in which radiocesium was rapidly removed and strongly bound at clay mineral particles in the sediment. These examples demonstrate the importance of detailed information concerning characteristics of specific compartments in ecosystems like fish, fungi, roe deer, etc. for reasonable decision making in terms of countermeasures to accidental contamination. (author)

  15. Analysis of long-term forest bird monitoring data from national forests of the western Great Lakes Region

    Science.gov (United States)

    Gerald J. Niemi; Robert W. Howe; Brian R. Sturtevant; Linda R. Parker; Alexis R. Grinde; Nicholas P. Danz; Mark D. Nelson; Edmund J. Zlonis; Nicholas G. Walton; Erin E. Gnass Giese; Sue M. Lietz

    2016-01-01

    Breeding bird communities in forests of the western Great Lakes region are among the most diverse in North America, but the forest environment in this region has changed dramatically during the past 150 years. To address concerns about loss of biodiversity due to ongoing forest harvesting and to better inform forest planning, researchers have systematically monitored...

  16. Special Forest Products on the Green Mountain and Finger Lakes National Forests: a research-based approach to management

    Science.gov (United States)

    Marla R. Emery; Clare. Ginger

    2014-01-01

    Special forest products (SFPs) are gathered from more than 200 vascular and fungal species on the Green Mountain National Forest (GMNF) and Finger Lakes National Forest (FLNF). This report documents those SFPs and proposes an approach to managing them in the context of legislation directing the U.S. Forest Service to institute a program of active SFP management. Based...

  17. Holocene evolution of lakes in the forest-tundra biome of northern Manitoba, Canada

    Science.gov (United States)

    Hobbs, William O.; Edlund, Mark B.; Umbanhowar, Charles E.; Camill, Philip; Lynch, Jason A.; Geiss, Christoph; Stefanova, Vania

    2017-03-01

    The late-Quaternary paleoenvironmental history of the western Hudson Bay region of Subarctic Canada is poorly constrained. Here, we present a regional overview of the post-glacial history of eight lakes which span the forest-tundra biome in northern Manitoba. We show that during the penultimate drainage phase of Lake Agassiz the lake water had an estimated pH of ∼6.0, with abundant quillwort (Isöetes spp.) along the lakeshore and littoral zone and some floating green algae (Botryococcus spp. and Pediastrum sp.). Based on multiple sediment proxies, modern lake ontogeny in the region commenced at ∼7500 cal yrs BP. Pioneering diatom communities were shaped by the turbid, higher alkalinity lake waters which were influenced by base cation weathering of the surrounding till following Lake Agassiz drainage. By ∼7000 cal yrs BP, soil development and Picea spp. establish and the lakes began a slow trajectory of acidification over the remaining Holocene epoch. The natural acidification of the lakes in this region is slow, on the order of several millennia for one pH unit. Each of the study lakes exhibit relatively stable aquatic communities during the Holocene Thermal Maximum, suggesting this period is a poor analogue for modern climatic changes. During the Neoglacial, the beginning of the post-Little Ice Age period represents the most significant climatic event to impact the lakes of N. Manitoba. In the context of regional lake histories, the rate of diatom floristic change in the last 200-300 years is unprecedented, with the exception of post-glacial lake ontogeny in some of the lakes. For nearly the entire history of the lakes in this region, there is a strong linkage between landscape development and the aquatic ecosystems; however this relationship appears to become decoupled or less strong in the post-LIA period. Significant 20th century changes in the aquatic ecosystem cannot be explained wholly by changes in the terrestrial ecosystem, suggesting that future

  18. Forest biomass estimated from MODIS and FIA data in the Lake States: MN, WI and MI, USA

    Science.gov (United States)

    Daolan Zheng; Linda S. Heath; Mark J. Ducey

    2007-01-01

    This study linked the Moderate Resolution Imaging Spectrometer and USDA Forest Service, Forest Inventory and Analysis (FIA) data through empirical models established using high-resolution Landsat Enhanced Thematic Mapper Plus observations to estimate aboveground biomass (AGB) in three Lake States in the north-central USA. While means obtained from larger sample sizes...

  19. Impact of forest harvesting on trophic structure of eastern Canadian Boreal Shield lakes: insights from stable isotope analyses.

    Directory of Open Access Journals (Sweden)

    Patricia Glaz

    Full Text Available Perturbations on ecosystems can have profound immediate effects and can, accordingly, greatly alter the natural community. Land-use such as forestry activities in the Canadian Boreal region have increased in the last decades, raising concerns about their potential impact on aquatic ecosystems. The objective of this study was to evaluate the impact of forest harvesting on trophic structure in eastern Canadian Boreal Shield lakes. We measured carbon and nitrogen stable isotopes values for aquatic primary producers, terrestrial detritus, benthic macroinvertebrates, zooplankton and brook trout (Salvelinus fontinalis over a three-year period in eight eastern Boreal Shield lakes. Four lakes were studied before, one and two years after forest harvesting (perturbed lakes and compared with four undisturbed reference lakes (unperturbed lakes sampled at the same time. Stable isotope mixing models showed leaf-litter to be the main food source for benthic primary consumers in both perturbed and unperturbed lakes, suggesting no logging impact on allochthonous subsidies to the littoral food web. Brook trout derived their food mainly from benthic predatory macroinvertebrates in unperturbed lakes. However, in perturbed lakes one year after harvesting, zooplankton appeared to be the main contributor to brook trout diet. This change in brook trout diet was mitigated two years after harvesting. Size-related diet shift were also observed for brook trout, indicating a diet shift related to size. Our study suggests that carbon from terrestrial habitat may be a significant contribution to the food web of oligotrophic Canadian Boreal Shield lakes. Forest harvesting did not have an impact on the diet of benthic primary consumers. On the other hand, brook trout diet composition was affected by logging with greater zooplankton contribution in perturbed lakes, possibly induced by darker-colored environment in these lakes one year after logging.

  20. Impact of forest harvesting on trophic structure of eastern Canadian Boreal Shield lakes: insights from stable isotope analyses.

    Science.gov (United States)

    Glaz, Patricia; Sirois, Pascal; Archambault, Philippe; Nozais, Christian

    2014-01-01

    Perturbations on ecosystems can have profound immediate effects and can, accordingly, greatly alter the natural community. Land-use such as forestry activities in the Canadian Boreal region have increased in the last decades, raising concerns about their potential impact on aquatic ecosystems. The objective of this study was to evaluate the impact of forest harvesting on trophic structure in eastern Canadian Boreal Shield lakes. We measured carbon and nitrogen stable isotopes values for aquatic primary producers, terrestrial detritus, benthic macroinvertebrates, zooplankton and brook trout (Salvelinus fontinalis) over a three-year period in eight eastern Boreal Shield lakes. Four lakes were studied before, one and two years after forest harvesting (perturbed lakes) and compared with four undisturbed reference lakes (unperturbed lakes) sampled at the same time. Stable isotope mixing models showed leaf-litter to be the main food source for benthic primary consumers in both perturbed and unperturbed lakes, suggesting no logging impact on allochthonous subsidies to the littoral food web. Brook trout derived their food mainly from benthic predatory macroinvertebrates in unperturbed lakes. However, in perturbed lakes one year after harvesting, zooplankton appeared to be the main contributor to brook trout diet. This change in brook trout diet was mitigated two years after harvesting. Size-related diet shift were also observed for brook trout, indicating a diet shift related to size. Our study suggests that carbon from terrestrial habitat may be a significant contribution to the food web of oligotrophic Canadian Boreal Shield lakes. Forest harvesting did not have an impact on the diet of benthic primary consumers. On the other hand, brook trout diet composition was affected by logging with greater zooplankton contribution in perturbed lakes, possibly induced by darker-colored environment in these lakes one year after logging.

  1. Forest-Product Imports and Exports Via the Great Lakes-St. Lawrence Seaway Through Upper Lakes Ports

    Science.gov (United States)

    Eugene M. Carpenter

    1966-01-01

    The expanded Great Lakes-St. Lawrence Seaway system was opened in the early spring of 1959, and for the first time deep-draft ocean-going vessels could visit inland Great Lakes ports. In 1963 the Station published a Research Note reporting what effect this expansion may have had on the volume of forest products moving through Minnesota, Wisconsin, and Michigan ports;...

  2. Vegetation Diversity Quality in Mountainous Forest of Ranu Regulo Lake Area, Bromo Tengger Semeru National Park, East Java

    Directory of Open Access Journals (Sweden)

    Jehan Ramdani Hariyati

    2012-01-01

    Full Text Available Aim of this research was to study vegetation diversity quality in mountainous forest of Ranu Regulo Lake area in Bromo Tengger Semeru National Park (TNBTS, East Java. Field observation was carried out by vegetation analysis using sampling plots of 25x25 m2 for trees, 5x5 m2 for poles, 1x1 m2 for ground surface plants. Community structure of each lake side was determined by calculating vegetation's density, basal area, frequency, important value and stratification of species. While vegetations diversity was estimated by taxa richness, Shannon-Wiener diversity index, and rate of endemism. Each lake side forests were compared by Morisita community similarity index. Data were tabulated by Microsoft Excel 2007. The result showed that based on existed vegetation, mountainous forest surrounding Ranu Regulo Lake consisted of four ecosystems, i.e. heterogenic mountainous forest, pine forest, acacia forest and bushes. Bushes Area has two types of population, edelweiss and Eupatorium odoratum invaded area. Vegetation diversity quality in heterogenic mountainous forest of Ranu Regulo TNBTS was the highest, indicated by its multi-stratification to B stratum trees of 20-30m high. Heterogenic mountainous forest’s formation was Acer laurinum and Acmena accuminatissima for trees, Chyatea for poles. Taxa richness was found 59 species and 30 families, while the others were found below 28 species and 17 families. Diversity Index of heterogenic mountainous forest is the highest among others for trees is 2.31 and 3.24 for poles and second in bushes (H=3.10 after edelweiss ecosystem (H=3.39. Highest rate of endemism reached 100% for trees in heterogenic mountainous forest, 87% for poles in edelweiss area and 89% for bushes also in heterogenic mountainous forest. Trees, poles and herbs most similarity community showed by pine and acacia forest. Based on those five characters, vegetation diversity quality in Ranu Regulo Lake area was medium for heterogenic mountainous

  3. Hydrologic Budget Assessment of a Small Forested Lake in Northwestern NJ

    Science.gov (United States)

    Kelly, S. A.; Barrett, K. R.; Galster, J. C.; Ophori, D. U.; Flores, D.; Jordan, J. J.; Lutey, A. M.

    2011-12-01

    Lake Wapalanne is a manmade lake, approximately 5.4 hectares, fed primarily by a small stream, with controlled outflow at a broad-crested weir. Located at the eastern edge of the Appalachian Ridge and Valley physiographic province in northwestern New Jersey, Lake Wapalanne and its watershed lie within a forested landscape, surrounded by 6500 hectares of protected land. The lake's location, small size, simplified inflow and outflow, and minimal external impacts provide a research environment ideal for studying present and future hydrologic lake dynamics. Quantifying the water budget for this small lake improves upon the existing understanding of regional surface water and groundwater interactions. Between July 13th and August 3rd we developed a hydrologic budget for Lake Wapalanne. We quantified precipitation, evapotranspiration, stream inflow and outflow, groundwater seepage, and lake water storage using direct and indirect methods. We installed a weather station to collect precipitation, evapotranspiration, and additional weather data used to calculate evaporation with the Penman-Shuttleworth equation. To develop a rating record between water depth and stream discharge, we installed water level loggers at the inlet and outlet streams and within the lake. To determine inlet and outlet discharge rates we used the midpoint method at 60% depth to measure velocity; we used a broad-crested weir equation to verify the outlet stream discharge. We measured groundwater using seepage meters and piezometers installed at various locations in the lake. To determine changes in lake water storage, we completed a bathymetry survey using a total station and used ArcGIS spatial analyst software to create relationships between depth, area, and volume. The water budget was computed in Excel with all variables quantified on a 15-minute interval. Our initial results indicate that the average total precipitation and evapotranspiration were 0.2 cm/day and 0.4 cm/day respectively. For a

  4. Forest changes since Euro-American settlement and ecosystem restoration in the Lake Tahoe Basin, USA

    Science.gov (United States)

    Alan H. Taylor

    2007-01-01

    Pre Euro-American settlement forest structure and fire regimes for Jeffrey pine-white fir, red fir-western white pine, and lodgepole pine forests were quantified using stumps from trees cut in the 19th century to establish a baseline reference for ecosystem management in the Lake Tahoe Basin. Contemporary forests varied in different ways compared...

  5. Recreation-related perceptions of natural resource managers in the Saranac Lakes wild forest area

    Science.gov (United States)

    Diane Kuehn; Mark Mink; Rudy Schuster

    2007-01-01

    Public forest managers often work with diverse stakeholder groups as they implement forest management policies. Within the Saranac Lakes Wild Forest area of New York State's Adirondack Park, stakeholder groups such as visitors, business owners, and landowners often have conflicting perceptions about issues related to water-based recreation in the region's...

  6. Landscape-scale modeling of water quality in Lake Superior and Lake Michigan watersheds: How useful are forest-based indicators? Journal of Great Lakes Research

    Science.gov (United States)

    Titus S. Seilheimer; Patrick L. Zimmerman; Kirk M. Stueve; Charles H. Perry

    2013-01-01

    The Great Lakes watersheds have an important influence on the water quality of the nearshore environment, therefore, watershed characteristics can be used to predict what will be observed in the streams. We used novel landscape information describing the forest cover change, along with forest census data and established land cover data to predict total phosphorus and...

  7. Microplastic pollution in lakes and lake shoreline sediments - A case study on Lake Bolsena and Lake Chiusi (central Italy).

    Science.gov (United States)

    Fischer, Elke Kerstin; Paglialonga, Lisa; Czech, Elisa; Tamminga, Matthias

    2016-06-01

    Rivers and effluents have been identified as major pathways for microplastics of terrestrial sources. Moreover, lakes of different dimensions and even in remote locations contain microplastics in striking abundances. This study investigates concentrations of microplastic particles at two lakes in central Italy (Lake Bolsena, Lake Chiusi). A total number of six Manta Trawls have been carried out, two of them one day after heavy winds occurred on Lake Bolsena showing effects on particle distribution of fragments and fibers of varying size categories. Additionally, 36 sediment samples from lakeshores were analyzed for microplastic content. In the surface waters 2.68 to 3.36 particles/m(3) (Lake Chiusi) and 0.82 to 4.42 particles/m(3) (Lake Bolsena) were detected, respectively. Main differences between the lakes are attributed to lake characteristics such as surface and catchment area, depth and the presence of local wind patterns and tide range at Lake Bolsena. An event of heavy winds and moderate rainfall prior to one sampling led to an increase of concentrations at Lake Bolsena which is most probable related to lateral land-based and sewage effluent inputs. The abundances of microplastic particles in sediments vary from mean values of 112 (Lake Bolsena) to 234 particles/kg dry weight (Lake Chiusi). Lake Chiusi results reveal elevated fiber concentrations compared to those of Lake Bolsena what might be a result of higher organic content and a shift in grain size distribution towards the silt and clay fraction at the shallow and highly eutrophic Lake Chiusi. The distribution of particles along different beach levels revealed no significant differences. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Site index comparisons for forest species in the Upper Great Lakes area of the United States and Canada

    Science.gov (United States)

    Willard H. Carmean; Jerold T. Hahn; Ronald E. McRoberts; D. Kaisershot

    2013-01-01

    This report summarizes six studies that compare site index relations between 24 hardwood and conifer species in the Upper Great Lakes area of the United States and Canada. These six studies have many regression models and graphs for comparing site index between forest species thus providing tools for estimating site index for alternative tree species based on direct...

  9. The necessity of management in a lake of the Atlantic Forest biodiversity hotspot: nitrogen levels connected to a persistent bloom of Cylindrospermopsis raciborskii

    OpenAIRE

    Figueredo,Cleber Cunha; Rückert,Gabriela von; Giani,Alessandra

    2016-01-01

    ABSTRACT Conservational studies of the threatened Atlantic Forest biome are frequently restricted to terrestrial ecosystems. We know little about the water bodies, specially considering that this biome covers the third largest system of lakes in Brazil. Some of these lakes are located inside the protected "Rio Doce State Park", but many others are found outside this reserve. These external lakes are seldom studied, but understanding their response to human activities is essential for the cons...

  10. Family forest landowners' interest in forest carbon offset programs: Focus group findings from the Lake States, USA

    Science.gov (United States)

    Kristell A. Miller; Stephanie A. Snyder; Mike A. Kilgore; Mae A. Davenport

    2014-01-01

    In 2012, focus groups were organized with individuals owning 20+ acres in the Lake States region of the United States (Michigan, Minnesota, and Wisconsin) to discuss various issues related to forest carbon offsetting. Focus group participants consisted of landowners who had responded to an earlier mail-back survey (2010) on forest carbon offsets. Two focus groups were...

  11. Impact of nitrogen deposition on forest and lake food webs in nitrogen-limited environments.

    Science.gov (United States)

    Meunier, Cédric L; Gundale, Michael J; Sánchez, Irene S; Liess, Antonia

    2016-01-01

    Increased reactive nitrogen (Nr ) deposition has raised the amount of N available to organisms and has greatly altered the transfer of energy through food webs, with major consequences for trophic dynamics. The aim of this review was to: (i) clarify the direct and indirect effects of Nr deposition on forest and lake food webs in N-limited biomes, (ii) compare and contrast how aquatic and terrestrial systems respond to increased Nr deposition, and (iii) identify how the nutrient pathways within and between ecosystems change in response to Nr deposition. We present that Nr deposition releases primary producers from N limitation in both forest and lake ecosystems and raises plants' N content which in turn benefits herbivores with high N requirements. Such trophic effects are coupled with a general decrease in biodiversity caused by different N-use efficiencies; slow-growing species with low rates of N turnover are replaced by fast-growing species with high rates of N turnover. In contrast, Nr deposition diminishes below-ground production in forests, due to a range of mechanisms that reduce microbial biomass, and decreases lake benthic productivity by switching herbivore growth from N to phosphorus (P) limitation, and by intensifying P limitation of benthic fish. The flow of nutrients between ecosystems is expected to change with increasing Nr deposition. Due to higher litter production and more intense precipitation, more terrestrial matter will enter lakes. This will benefit bacteria and will in turn boost the microbial food web. Additionally, Nr deposition promotes emergent insects, which subsidize the terrestrial food web as prey for insectivores or by dying and decomposing on land. So far, most studies have examined Nr -deposition effects on the food web base, whereas our review highlights that changes at the base of food webs substantially impact higher trophic levels and therefore food web structure and functioning. © 2015 John Wiley & Sons Ltd.

  12. Estimation of Unregulated Monthly, Annual, and Peak Streamflows in Forest City Stream and Lake Levels in East Grand Lake, United States-Canadian Border Between Maine and New Brunswick

    Science.gov (United States)

    Lombard, Pamela J.

    2018-04-30

    The U.S. Geological Survey, in cooperation with the International Joint Commission compiled historical data on regulated streamflows and lake levels and estimated unregulated streamflows and lake levels on Forest City Stream at Forest City, Maine, and East Grand Lake on the United States-Canadian border between Maine and New Brunswick to study the effects on streamflows and lake levels if two or all three dam gates are left open. Historical regulated monthly mean streamflows in Forest City Stream at the outlet of East Grand Lake (referred to as Grand Lake by Environment Canada) fluctuated between 114 cubic feet per second (ft3/s) (3.23 cubic meters per second [m3/s]) in November and 318 ft3/s (9.01 m3/s) in September from 1975 to 2015 according to Environment Canada streamgaging data. Unregulated monthly mean streamflows at this location estimated from regression equations for unregulated sites range from 59.2 ft3/s (1.68 m3/s) in September to 653 ft3/s (18.5 m3/s) in April. Historical lake levels in East Grand Lake fluctuated between 431.3 feet (ft) (131.5 meters [m]) in October and 434.0 ft (132.3 m) in May from 1969 to 2016 according to Environment Canada lake level data for East Grand Lake. Average monthly lake levels modeled by using the estimated hydrology for unregulated flows, and an outflow rating built from a hydraulic model with all gates at the dam open, range from 427.7 ft (130.4 m) in September to 431.1 ft (131.4 m) in April. Average monthly lake levels would likely be from 1.8 to 5.4 ft (0.55 to 1.6 m) lower with the gates at the dam opened than they have been historically. The greatest lake level changes would be from June through September.

  13. Lake Nasser evaporation reduction study

    Directory of Open Access Journals (Sweden)

    Hala M.I. Ebaid

    2010-10-01

    Full Text Available This study aims to evaluate the reduction of evaporation of Lake Nasser’s water caused by disconnecting (fully or partially some of its secondary channels (khors. This evaluation integrates remote sensing, Geographic Information System (GIS techniques, aerodynamic principles, and Landsat7 ETM+ images. Three main procedures were carried out in this study; the first derived the surface temperature from Landsat thermal band; the second derived evaporation depth and approximate evaporation volume for the entire lake, and quantified evaporation loss to the secondary channels’ level over one month (March by applied aerodynamic principles on surface temperature of the raster data; the third procedure applied GIS suitability analysis to determine which of these secondary channels (khors should be disconnected. The results showed evaporation depth ranging from 2.73 mm/day at the middle of the lake to 9.58 mm/day at the edge. The evaporated water-loss value throughout the entire lake was about 0.86 billion m3/month (March. The analysis suggests that it is possible to save an approximate total evaporation volume loss of 19.7 million m3/month (March, and thus 2.4 billion m3/year, by disconnecting two khors with approximate construction heights of 8 m and 15 m. In conclusion, remote sensing and GIS are useful for applications in remote locations where field-based information is not readily available and thus recommended for decision makers remotely planning in water conservation and management.

  14. Soil mesofauna in disturbed spruce forest stands near Čertovo and Plešné Lakes, the Bohemian Forest: preliminary results

    Science.gov (United States)

    Čuchta, Peter; Starý, Jozef

    2016-04-01

    The soil microarthropod communities were studied in disturbed spruce forest stands in the catchments areas of Čertovo (CT) and Plešné (PL) Lakes in the Bohemian Forest, Czech Republic. The study is focused on the impact of the windthrow, bark beetle outbreak damage and consecutive changes in the forest stands including soil environment. Within the soil microarthropods, two main groups, Collembola (Hexapoda) and Oribatida (Acari) are analysed. Four different treatments were selected for the study on both study areas: CT1 and PL1 stands - undamaged control forest stands, CT2 and PL2 stands - "dead" forest stands damaged by bark beetle, CT3 and PL3 stands - slightly managed windthrown forest stands left for the natural succession, and CT4 and PL4 stands - harvested windthrown stands. Soil samples were taken in June (CT1/PL1 - CT3/PL3), July and October (CT1/PL1 - CT4/PL4) 2012 from each treatment. Microarthropods were subsequently extracted in a modified high-gradient apparatus in the laboratory for seven days. Finally, the comparison of the microarthropod assemblages found at different treatment stands was performed. The most abundant groups in both study areas (Čertovo and Plešné Lakes) were Collembola and Oribatida with considerable diferences within particular treatments and in time as well.

  15. Isotope techniques in lake water studies

    International Nuclear Information System (INIS)

    Gourcy, L.

    1999-01-01

    Freshwater lakes are among the most easily exploitable freshwater resources. Lakes are also recognized as major sedimentological features in which stored material can be used to study recent climate and pollution evolution. To adequately preserve these important landscape features, and to use them as climatic archives, an improved understanding of processes controlling their hydrologic and bio-geochemical environments if necessary. This article briefly describes the IAEA activities related to the study of lakes in such areas as lake budget, lake dynamics, water contamination, and paleolimnological investigations

  16. Soil Collembola communities within Plešné Lake and Čertovo Lake catchments, the Bohemian Forest

    Czech Academy of Sciences Publication Activity Database

    Čuchta, Peter

    2016-01-01

    Roč. 18, April (2016), EGU2016-2971 ISSN 1607-7962. [European Geosciences Union General Assembly 2016. 17.04.2016-22.04.2016, Vienna] Institutional support: RVO:60077344 Keywords : soil Collembola communities * Plešné and Čertovo Lakes * Bohemian Forest Subject RIV: EH - Ecology, Behaviour

  17. 77 FR 21721 - Sierra National Forest, Bass Lake Ranger District, California, Whisky Ecosystem Restoration Project

    Science.gov (United States)

    2012-04-11

    ... National Forest, Bass Lake Ranger District, California, Whisky Ecosystem Restoration Project AGENCY: Forest...: Background Information: The Whisky Ecosystem Restoration Project (Madera County, California) lies within the... Species for Region 5. Purpose and Need for Action The purpose of this Project is to promote ecosystem...

  18. An outlook for sustainable forest bioenergy production in the Lake States

    Science.gov (United States)

    Dennis R. Becker; Kenneth Skog; Allison Hellman; Kathleen E. Halvorsen; Terry Mace

    2009-01-01

    The Lake States region of Minnesota, Wisconsin and Michigan offers significant potential for bioenergy production. We examine the sustainability of regional forest biomass use in the context of existing thermal heating, electricity, and biofuels production, projected resource needs over the next decade including existing forest product market demand, and impacts on...

  19. Effects of Lakes on Wildfire Activity in the Boreal Forests of Saskatchewan, Canada

    Directory of Open Access Journals (Sweden)

    Scott E. Nielsen

    2016-11-01

    Full Text Available Large lakes can act as firebreaks resulting in distinct patterns in the forest mosaic. Although this is well acknowledged, much less is known about how wildfire is affected by different landscape measures of water and their interactions. Here we examine how these factors relate to historic patterns of wildfire over a 35-year period (1980–2014 for the boreal forest of Saskatchewan, Canada. This includes the amount of water in different-sized neighborhoods, the presence of islands, and the direction, distance, and shape of nearest lake of different sizes. All individual factors affected wildfire presence, with lake sizes ≥5000 ha and amount of water within a 1000-ha surrounding area the most supported spatial scales. Overall, wildfires were two-times less likely on islands, more likely further from lakes that were circular in shape, and in areas with less surrounding water. Interactive effects were common, including the effect of direction to lake as a function of distance from lakeshore and amount of surrounding water. Our results point to a strong, but complex, bottom-up control of local wildfire activity based on the configuration of natural firebreaks. In fact, fire rotation periods predicted for one area varied more than 15-fold (<47 to >700 years depending on local patterns in lakes. Old-growth forests within this fire-prone ecosystem are therefore likely to depend on the surrounding configuration of larger lakes.

  20. The necessity of management in a lake of the Atlantic Forest biodiversity hotspot: nitrogen levels connected to a persistent bloom of Cylindrospermopsis raciborskii

    Directory of Open Access Journals (Sweden)

    Cleber Cunha Figueredo

    2016-01-01

    Full Text Available ABSTRACT Conservational studies of the threatened Atlantic Forest biome are frequently restricted to terrestrial ecosystems. We know little about the water bodies, specially considering that this biome covers the third largest system of lakes in Brazil. Some of these lakes are located inside the protected "Rio Doce State Park", but many others are found outside this reserve. These external lakes are seldom studied, but understanding their response to human activities is essential for the conservation and the protection of the lakes inside the Park. We evaluated the effects of degradation in a lake outside the Park, which shows a constant bloom of the toxic invasive cyanobacteria Cylindrospermopsis raciborskii. Phytoplankton, climate and physico-chemical variables were assessed from 2011 to 2013 to evaluate which were the major determinants of the lake dynamics. Despite the seasonal changes, the lake was always eutrophic, and cyanobacteria, transparency and nutrients were the major indicators of water characteristics. The lake seems to be nitrogen-limited and cyanobacteria were negatively correlated with nitrogen levels, since the constantly dominant C. raciborskii is a superior competitor for N. We suggest that the monitoring of nitrogen levels is fundamental to establish management strategies to avoid harmful algae blooms in this Atlantic Forest lake.

  1. The Bonobo Pan paniscus (Mammalia: Primates: Hominidae nesting patterns and forest canopy layers in the Lake Tumba forests and Salonga National Park, Democratic Republic of Congo

    Directory of Open Access Journals (Sweden)

    Bila-Isia Inogwabini

    2015-10-01

    Full Text Available The description and differentiation of habitat types is a major concern in ecology.  This study examined relationships between Bonobo Pan paniscus nesting patterns and forest structure in the Lake Tumba Swampy Forests. Data on presence of fresh Bonobo nests, canopy cover, canopy structure, tree densities and tree basal areas were collected systematically along 134 transects at 400m and 800m intervals, and the leaf-covered area (LCA was calculated for each of seven forest types. I observed a significant correlation between bonobo nests and mixed mature forest/closed understory forest type (r=-0.730, df = 21, p <0.05, but not mixed mature forest/open understory, old secondary forest and young secondary forest.  Basal areas of non-nesting trees along transects did not differ significantly from those in sites where bonobos nested.  Higher LCA (55% and 55% occurred in nesting sites when compared with non-nesting sites (39% and 42% at elevations 4–8 m and 8–16 m above the soil.  There was greater leaf cover in the understorey at sites where bonobos did not nest, while there was greater leaf cover in the mid-storey at sites where bonobos did nest.  

  2. Seasonal and inter-annual variations in methyl mercury concentrations in zooplankton from boreal lakes impacted by deforestation or natural forest fires.

    Science.gov (United States)

    Garcia, Edenise; Carignan, Richard; Lean, David R S

    2007-08-01

    We compared the effects of natural and anthropogenic watershed disturbances on methyl mercury (MeHg) concentration in bulk zooplankton from boreal Shield lakes. MeHg in zooplankton was monitored for three years in nine lakes impacted by deforestation, in nine lakes impacted by wildfire, and in twenty lakes with undisturbed catchments. Lakes were sampled during spring, mid- and late summer. MeHg in zooplankton showed a seasonal trend: concentrations were the lowest in spring, then peaked in mid-summer and decreased in late summer. Over the three study years, MeHg concentrations observed in mid-summer in zooplankton from forest harvested lakes were significantly higher than in reference and fire-impacted lakes, whereas differences between these two groups of lakes were not significant. The pattern of distribution of MeHg in zooplankton during the different seasons paralleled that of dissolved organic carbon (DOC), which is known as a vector of Hg from watershed soils to lake water. Besides DOC, MeHg in zooplankton also showed a positive significant correlation with epilimnetic temperature and sulfate concentrations. An inter-annual decreasing trend in MeHg was observed in zooplankton from reference and fire-impacted lakes. In forest harvested lakes, however, MeHg concentrations remained higher and nearly constant over three years following the impact. Overall these results indicate that the MeHg pulse observed in zooplankton following deforestation by harvesting is relatively long-lived, and may have repercussions to the accumulation of MeHg along the food chain. Therefore, potential effects of deforestation on the Hg contamination of fish should be taken into account in forest management practices.

  3. Lake Titicaca: History and current studies

    International Nuclear Information System (INIS)

    Paredes Riveros, M.A.; Gonfiantini, R.

    1999-01-01

    This article summarizes results of Titicaca lake water balance studies including the findings of the IAEA Technical Cooperation Project RLA/08/022. Direct precipitation over the lake accounts for about 55% of the water inflow and rivers and streams provide about 45% of the water inflow. Diffuse groundwater leakage into the lake from coastal aquifers is believed to represent a negligible term of water balance. Evaporation from the lake is strong and accounts for more than 95% of the water losses. The isotopic and chemical composition data obtained within the frameworks of the IAEA Technical Cooperation Project RLA/08/022 are discussed

  4. Extraction and detection of baculoviral DNA from lake water, detritus and forest litter.

    Science.gov (United States)

    England, L S; Trevors, J T; Holmes, S B

    2001-04-01

    This paper describes a quick, reproducible, sensitive method for baculoviral DNA extraction, purification and detection from freshwater and forest litter environments. The extraction protocol utilizes enzymatic and chemical lysis and physical disruption. To assess the efficiency of the extraction and purification protocol, PCR was used to detect a 530 bp DNA fragment from the genome of a genetically-modified baculovirus, Choristoneura fumiferana NPVegt-/lacZ+. The detection limit of PCR amplification was routinely about 4.1 x 102 occlusion bodies (OBs) 450 microl-1 lake water. Template DNA from the detritus and forest litter samples required 100-fold dilutions before use in PCR reactions. The detection limits for detritus and forest litter samples were routinely about 7.41 x 103 and 2.08 x 104 OBs 0.5 g-1 dry weight, respectively. The DNA extraction and purification methodology is reproducible, sensitive and can be used in lieu of, or in conjunction with, insect bioassays. The DNA extraction and purification protocol described in this paper will facilitate risk assessment and ecological studies of both wild-type and genetically-modified baculoviruses.

  5. Change in the forested and developed landscape of the Lake Tahoe basin, California and Nevada, USA, 1940-2002

    Science.gov (United States)

    Raumann, C.G.; Cablk, Mary E.

    2008-01-01

    The current ecological state of the Lake Tahoe basin has been shaped by significant landscape-altering human activity and management practices since the mid-1850s; first through widespread timber harvesting from the 1850s to 1920s followed by urban development from the 1950s to the present. Consequences of landscape change, both from development and forest management practices including fire suppression, have prompted rising levels of concern for the ecological integrity of the region. The impacts from these activities include decreased water quality, degraded biotic communities, and increased fire hazard. To establish an understanding of the Lake Tahoe basin's landscape change in the context of forest management and development we mapped, quantified, and described the spatial and temporal distribution and variability of historical changes in land use and land cover in the southern Lake Tahoe basin (279 km2) from 1940 to 2002. Our assessment relied on post-classification change detection of multi-temporal land-use/cover and impervious-surface-area data that were derived through manual interpretation, image processing, and GIS data integration for four dates of imagery: 1940, 1969, 1987, and 2002. The most significant land conversion during the 62-year study period was an increase in developed lands with a corresponding decrease in forests, wetlands, and shrublands. Forest stand densities increased throughout the 62-year study period, and modern thinning efforts resulted in localized stand density decreases in the latter part of the study period. Additionally forests were gained from succession, and towards the end of the study period extensive tree mortality occurred. The highest rates of change occurred between 1940 and 1969, corresponding with dramatic development, then rates declined through 2002 for all observed landscape changes except forest density decrease and tree mortality. Causes of landscape change included regional population growth, tourism demands

  6. Grow--a computer subroutine that projects the growth of trees in the Lake States' forests.

    Science.gov (United States)

    Gary J. Brand

    1981-01-01

    A computer subroutine, Grow, has been written in 1977 Standard FORTRAN to implement a distance-independent, individual tree growth model for Lake States' forests. Grow is a small and easy-to-use version of the growth model. All the user has to do is write a calling program to read initial conditions, call Grow, and summarize the results.

  7. U.S. Forest Service Region 1 Lake Chemistry, NADP, and IMPROVE air quality data analysis

    Science.gov (United States)

    Jill Grenon; Mark Story

    2009-01-01

    This report was developed to address the need for comprehensive analysis of U.S. Forest Service (USFS) Region 1 air quality monitoring data. The monitoring data includes Phase 3 (long-term data) lakes, National Atmospheric Deposition Program (NADP), and Interagency Monitoring of Protected Visual Environments (IMPROVE). Annual and seasonal data for the periods of record...

  8. Glaciation in the surroundings of Prášilské Lake (Bohemian Forest, Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Mentlík, P.; Minár, J.; Břízová, E.; Lisá, Lenka; Tábořík, P.; Stacke, V.

    2010-01-01

    Roč. 117, 1/2 (2010), s. 181-194 ISSN 0169-555X Institutional research plan: CEZ:AV0Z30130516 Keywords : Bohemian Forest * Pleistocene glaciations * Prášilské Lake * Šumava * sedimentology * chronology Subject RIV: DB - Geology ; Mineralogy Impact factor: 2.352, year: 2010

  9. Development of a GIS interface for WEPP Model application to Great Lakes forested watersheds

    Science.gov (United States)

    J. R. Frankenberger; S. Dun; D. C. Flanagan; J. Q. Wu; W. J. Elliot

    2011-01-01

    This presentation will highlight efforts on development of a new online WEPP GIS interface, targeted toward application in forested regions bordering the Great Lakes. The key components and algorithms of the online GIS system will be outlined. The general procedures used to provide input to the WEPP model and to display model output will be demonstrated.

  10. Mapping forest canopy disturbance in the Upper Great Lakes, USA

    Science.gov (United States)

    James D. Garner; Mark D. Nelson; Brian G. Tavernia; Charles H. (Hobie) Perry; Ian W. Housman

    2015-01-01

    A map of forest canopy disturbance was generated for Michigan, Wisconsin, and most of Minnesota using 42 Landsat time series stacks (LTSS) and a vegetation change tracker (VCTw) algorithm. Corresponding winter imagery was used to reduce commission errors of forest disturbance by identifying areas of persistent snow cover. The resulting disturbance age map was classed...

  11. A Systematic Study of Zerbar Lake Restoration

    Science.gov (United States)

    Hosseini, Reza; Oveis Torabi, Seyed; Forman Asgharzadeh, Deonna

    2017-04-01

    The beautiful lake of Zerbar, located near Marivan City at the west of Iran, is a freshwater lake with an area of 20 km2 and average depth of 5 meters. The lake is created by regional tectonic activities and is mainly fed with natural spring water from bottom. During the past three decades, regional development has caused much disturbance to the natural environment of the lake and its watershed. Rescuing the lake is crucial to the sustainability of the whole region. The study of Zerbar Restoration was performed with the aim to restore its health indicators. Variety of human activities in the watershed, as well as the multidisciplinary nature of lake restoration studies, made it necessary to develop a systematic approach to conduct the study. In Step I of restoration studies, satellite images were investigated to identify the historical changes of watershed during the past 30 years. Meanwhile, documents since 50 years ago were studied. Results indicate that farmland and graze land areas have been relatively constant during the past 50 years. Also, the area of lake, its riparian canes and floating plants have not changed much. In fact, the only significant land use change observed was the significant spread of Marivan City that has stretched toward the lake. The main physical variation to the lake has been elevating the southern edge of the lake by a constructing a landfill dam which was done to control the lake's overflow discharge for irrigation of downstream farmland development. Step II consists of studies performed by disciplines of water resources, hydrogeology, water quality, wetland and watershed ecology, agriculture, animal farming and fishery. Study results indicate that eutrophication (TSL>100), mainly caused by sewage from Marivan City and the surrounding rural areas has been the main reason for lake ecosystem degradation. DPSIR framework, as a novel approach in lake restoration, was applied to synthesize the study results of different disciplines in a

  12. Preliminary results of a study on the soil mesofauna in disturbed spruce forest stands near Čertovo and Plešné Lakes in the Bohemian Forest (Czech Republic)

    Czech Academy of Sciences Publication Activity Database

    Čuchta, Peter; Starý, Josef

    2015-01-01

    Roč. 79, č. 3 (2015), s. 161-167 ISSN 1211-376X R&D Projects: GA ČR GAP504/12/1218 Institutional support: RVO:60077344 Keywords : windthrow * bark beetle * soil arthropods * Bohemian Forest Subject RIV: EH - Ecology, Behaviour

  13. Waxing and Waning of Forests: Late Quaternary Biogeography of Lake Malawi, Southeast Africa

    Science.gov (United States)

    Ivory, S.; Lézine, A. M.; Vincens, A.; Cohen, A. S.

    2014-12-01

    African ecosystems are at great risk due to climate and land-use change. Despite the status of several of these regions as biodiversity hotspots, long-standing ideas about African ecology and biogeography have been unable to be tested until now due to lack of sufficiently long records. Here, we present the first long, continuous terrestrial record of vegetation from Lake Malawi, East Africa which goes back to the early Late Quaternary, permitting us to investigate changes in physiognomy and forest composition over many transitions. In this record, we observe eight phases of forest expansion and collapse. Although diversity is much greater during forest phases, composition varies little from phase to phase. Very high abundances of afromontane taxa suggest frequent widespread colonization of the lowlands by modern high elevation trees. Although there are clear successional stages within each forest such that turnover is great within a single phase, among forest samples between phases, there is little dissimilarity. Each forest phase is interrupted by rapid decline of arboreal taxa and expansion of semi-arid grasslands or woodlands whose composition varies greatly from phase to phase. The variable composition of the more open phases, all occurring during arid periods, is likely dynamically linked to thresholds in regional hydrology associated with lake level and moisture recycling within the watershed. This vegetation is unlike any found at Malawi today, with assemblages suggesting strong Somali-Masai affinities. Furthermore, nearly all semi-arid assemblages contain small abundances of forest taxa typically growing in areas with wetter edaphic conditions, suggesting that moist lowland gallery forests were present but restricted to waterways during exceptionally arid times. The waxing and waning of forests throughout this interval has important implications for early human biogeography across Africa as well as disturbance regimes that are crucial for the maintenance of

  14. Public perspectives of fire, fuels, and the Forest Service in the Great Lakes Region: a survey of citizen-agency communication and trust

    Science.gov (United States)

    Bruce A. Shindler; Eric Toman; Sarah M. McCaffrey

    2009-01-01

    Relative to the western United States, where fire and fuel management programs have received greater emphasis, few community-based studies have focused on the Great Lakes region. The present paper describes public opinion research from counties surrounding National Forests inWisconsin, Minnesota and Michigan. Survey data address citizen perspectives on (1) fuel...

  15. Evolution of alkaline lakes - Lake Van case study

    Science.gov (United States)

    Tillman Meyer, Felix; Viehberg, Finn; Bahroun, Sonya; Wolf, Annabel; Immenhauser, Adrian; Kwiecien, Ola

    2017-04-01

    Lake Van in Eastern Anatolia (Turkey) is the largest terminal soda lake on Earth. The lake sedimentary profile covers ca. 600 ka (Stockhecke et al. 2014) Based on lithological changes, the presence of freshwater microfossils and close-to-freshwater pH value in the pore water, members of ICDP PALEOVAN concluded that Lake Van might have started as an open lake. Here we show paleontological and geochemical evidence in favour of this idea and constrain the time, when Lake Van likely transformed into a closed lake. Additionally we provide the first conceptual model of how this closure may have happened. Our archives of choice are inorganic and biogenic carbonates, separated by wet sieving. We identified microfossil assemblages (fraction > 125 µm) and performed high-resolution oxygen isotope (delta18O) and elemental (Mg/Ca, Sr/Ca) analyses of the fraction plants growing in the photic zone as food supply. These two aspects point to an increasing salinity in a shallowing lake. The delta18O values of inorganic carbonates are relatively low during the initial phase of Lake Van and increase abruptly (ca. 7‰) after 530 ka BP. At approximately the same time combination of Sr/Ca and Mg/Ca data suggest first occurrence of aragonite. Again, these findings suggest geochemical changes of the lake water concurrent with transition documented by microfossils. Comparison between Lake Van and Lake Ohrid (Lacey et al. 2016) delta18O data, precludes regional climate change (e.g.: increased evaporation) as the main driver of observed changes. With no evidence for increased volcanic or tectonic activity (e.g.: tephra layers, deformation structures, slumping) in the Lake Van sedimentary profile around 530 ka, it seems unlikely that a pyroclastic flow blocked the outflow of the lake. Alternatively, a portion of inflow has been diverged which might have caused a change in the hydrological balance and lake level falling below its outlet. However, as no geomorphological data confirming this

  16. Pyrogenic Transformations of the Baikal Lake Forests. Retrospective and Contemporary Issues

    Directory of Open Access Journals (Sweden)

    M. D. Yevdokimenko

    2014-06-01

    Full Text Available In the forests of the Baikal Lake basin annual fire activity historically has been higher as compared to surrounding forest areas due to specific climatic conditions and altitude-controlled vegetation structure. The regional forests, predominantly light coniferous, develop under a high or, in dry years, extreme-fire-activity regime. Common pine and larch tree stands of fire origin are periodically thinned by fire. The productivity of the fire-intact parts of such stands decreases as a result of fire-caused soil condition disturbances. In extreme fire years, large fires cover landscapes and lead to irreversible forest ecosystem degradation and, hence, to local deforestation. In the past, forest fire activity and area burned increased with increasing use of the regional forests beginning with hunting, wood extraction by dwellers of local settlements, Trans-Siberian Rail Road building and, finally, industrial-scale logging. In 1970–1980, the regional fire situation was successfully controlled due to improvements of forest use and protection. However, the recently relaxed forest economy standards have resulted in loss of the progress achieved.

  17. Family Forest Landowners' Interest in Forest Carbon Offset Programs: Focus Group Findings from the Lake States, USA

    Science.gov (United States)

    Miller, Kristell A.; Snyder, Stephanie A.; Kilgore, Mike A.; Davenport, Mae A.

    2014-12-01

    In 2012, focus groups were organized with individuals owning 20+ acres in the Lake States region of the United States (Michigan, Minnesota, and Wisconsin) to discuss various issues related to forest carbon offsetting. Focus group participants consisted of landowners who had responded to an earlier mail-back survey (2010) on forest carbon offsets. Two focus groups were held per state with an average of eight participants each (49 total). While landowner participant types varied, overall convergence was reached on several key issues. In general, discussion results found that the current payment amounts offered for carbon credits are not likely, on their own, to encourage participation in carbon markets. Landowners are most interested in other benefits they can attain through carbon management (e.g., improved stand species mix, wildlife, and trails). Interestingly, landowner perceptions about the condition of their own forest land were most indicative of prospective interest in carbon management. Landowners who felt that their forest was currently in poor condition, or did not meet their forest ownership objectives, were most interested in participating. While the initial survey sought landowner opinions about carbon markets, a majority of focus group participants expressed interest in general carbon management as a means to achieve reduced property taxes.

  18. Bibliography of publications and manuscripts relating to the Bohemian/Bavarian Forest lakes

    Czech Academy of Sciences Publication Activity Database

    Vrba, Jaroslav (ed.)

    2000-01-01

    Roč. 4, č. 4 (2000), s. 259-278 ISSN 1211-7420. [Acidified Lakes in the Bohemian/Bavarian Forest - History, Present and Future. Č. Budějovice, 21.03.2000-23.03.2000] R&D Projects: GA ČR GA206/97/0072; GA ČR GA206/98/0727 Subject RIV: DA - Hydrology ; Limnology

  19. Vegetation changes and human activity around Lake Łańskie (Olsztyn Lake District, NE Poland from the mid Holocene, based on palynological study

    Directory of Open Access Journals (Sweden)

    Madeja Jacek

    2013-12-01

    Full Text Available Bottom sediments of Lake Łańskie in NE Poland (Olsztyn Lake District were studied by pollen analysis, and vegetation changes from ca 4800 BC to modern times were reconstructed based on the results. Due to rapid sedimentation the changes in plant cover are recorded with high resolution. The variation of pollen spectra composition reflects changing shares of deciduous trees and the continuous dominance of pine forest. Nowadays the surroundings of Lake Łańskie are also heavily forested but as early as 1100 AD the deciduous trees began to be eliminated. On the basis of pollen data, five phases of increased human activity were distinguished. Based on the available archaeological chronology of local settlements, the first stage is connected with para-Neolithic groups of Ząbie-Szestno type and the Lusatian culture. They are followed by the West Baltic Barrow culture, Wielbark culture and Early Medieval Prussian tribes. The pollen record shows low intensity of exploitation of the terrain around Lake Łańskie, probably attributable to the brevity of episodes of human occupation in the near vicinity of the lake. The last phase, covering part of the Middle Ages (since ca 1000 AD and modern times, is reflected in the most distinct vegetation changes on the pollen diagram, caused by increased intensity of settlement. In spite of the distinct diminution of forest cover around the lake the scale of deforestation was much lower than at other sites in NE Poland.

  20. Properties of soils and tree-wood tissue across a Lake States sulfate-deposition gradient. Forest Service resource bulletin

    International Nuclear Information System (INIS)

    Ohmann, L.F.; Grigal, D.F.

    1991-01-01

    There is general concern that atmospheric pollutants may be affecting the health of forests in the USA. The hypotheses tested were that the wet sulfate deposition gradient across the Lake States: (1) is reflected in the amount of accumulated sulfur in the forest floor-soil system and tree woody tissue and (2) is related to differences in tree radial increment. The authors present the properties of the soil and tree woody tissue (mostly chemical) on the study plots. Knowledge of the properties of soil and woody tree tissue is needed for understanding and interpreting relations between sulfate deposition, sulfur accumulation in the ecosystem, soil and tree chemistry, and tree growth and climatic variation. The report provides a summary of those data for study, analysis, and interpretation

  1. Evaluation of Sugar Maple Dieback in the Upper Great Lakes Region and Development of a Forest Health Youth Education Program

    Science.gov (United States)

    Bal, Tara L.

    2013-01-01

    Sugar Maple, "Acer saccharum" Marsh., is one of the most valuable trees in the northern hardwood forests. Severe dieback was recently reported by area foresters in the western Upper Great Lakes Region. Sugar Maple has had a history of dieback over the last 100 years throughout its range and different variables have been identified as…

  2. Landscape patterns of montane forest age structure relative to fire history at Cheesman Lake in the Colorado Front Range

    Science.gov (United States)

    Laurie S. Huckaby; Merrill R. Kaufmann; Jason M. Stoker; Paula J. Fornwalt

    2001-01-01

    Lack of Euro-American disturbance, except fire suppression, has preserved the patterns of forest structure that resulted from the presettlement disturbance regime in a ponderosa pine/Douglas-fir landscape at Cheesman Lake in the Colorado Front Range. A mixed-severity fire regime and variable timing of tree recruitment created a heterogeneous forest age structure with...

  3. Climatic gradients and human development pressure determine spatial patterns of forest fragmentation in the Great Lakes basin, USA

    Science.gov (United States)

    Currie, W. S.; Hart, S.

    2015-12-01

    Over half of temperate forest area globally has been fragmented or deforested by human activities. Our objective was to gain insight into the combination of climatic, ecological, and social factors that control complex spatial patterns of forest cover and fragmentation at the regional scale. Our study area was the US portion of the land area of the Laurentian Great Lakes basin (USGL basin) of the Upper Midwest, USA, covering ca. 300,000 km2 and home to 25 million people. While this region was historically forested, today there are regional gradients in forest cover as well as complex spatial patterns of agriculture, human settlements, and tree cover. This includes large expanses of fragmented forests in the wildland-urban interface or the forest transition zone. We used structural equation modeling to test models of social and climatic-ecological factors to explain spatial patterns of forest cover and fragmentation. This is a model-driven approach to statistical analysis that is used to test proposed causal "structures" of direct and indirect relationships among variables. It is an innovative approach that makes use of large spatial datasets to test understanding. We assembled numerous spatial data layers at 1 km2 resolution across the USGL basin. We found that 64% to 75% of variance in tree cover and forest connectivity was explained through a relatively simple model combining climatic gradients and human development pressure. Human development pressure was best represented as a measurement model that explained 45% of variance in road density and 87% of housing unit density, while significantly explaining patterns of forest fragmentation. Climate could be represented by a single variable, temperature: where temperature was higher, tree cover and forest connectivity was lower due to human land use. Temperatures did not help to explain patterns of human development as roads and housing, but did affect forest fragmentation through land use as cropland. This suggests

  4. Isotope studies on dynamics and sedimentation in Lake Naini, India

    International Nuclear Information System (INIS)

    Rao, S.M.; Kumar, U.S.; Shivanna, K.; Sinha, U.K.; Sharma, S.

    2001-01-01

    Understanding hydrodynamics of a water body like a lake is a prerequisite for planning and managing its use. In the present study, isotope techniques are employed to study the dynamics and sedimentation pattern of Lake Naini, in India. From the study a few observations are made: (i) the Lake is a warm monomictic one; (ii) the presence of a centrally submerged ridge in the Lake plays a vital role in the intermixing of the Lake's two sub-basins; (iii) the Lake-Groundwater system is a flow-through type and (iv) the Lake is not shallowing at a rate reported by earlier investigators and has different depositional zones with constant/varying sedimentation rates. A Tritium and Water Balance Model is developed to estimate the water retention time of the Lake and also the groundwater residence time between precipitation and input to the Lake. (author)

  5. The study of Lake Urmia desiccation: morphometry impress

    Science.gov (United States)

    Moradi, Ayoub; Rasouli, Ali Akbar; Roostaei, Shahram

    2017-04-01

    Located in northwestern Iran, the hypersaline Lake Urmia has started a serious uninterrupted desiccation since 1995. The lake has lost about eight meters of water level and about 75% of water surface area during past 20 years. In particular, the lake water volume decrement has been accelerated in recent years. The importance of the Lake Urmia for human life in northwestern Iran, and its destructive effects on a vast region if totally dry up, demands comprehensive studies of the lake level fluctuations mechanism. According to literature review, the water volume of the lake behaves sometimes differently from the water storage of the whole basin. Our time series analysis using Land Data Assimilation Systems also confirms those differences within last decades. In other hand, many studies addressed the lake desiccation to climatic changes and/or anthropogenic influences such as excessive dam constructions in the watershed during last decades. As water leaves the lake only through evaporation, the fluctuation of evaporation has a distinctive role in the lake level variations. Dramatic decreament in the lake extent indicates of a special morphometry. The lake's morphometry has made it vulnerable to temperature and salinity changes. It strongly controls the lake's water heat capacity and water density. And, it therefore controls the rate of evaporation from water surface. We study the role of lake's morphometry on the lake desiccation. Although, the global climatic change is known as the primary reason for current droughts in the Middle East generally, our preliminary results show that the lake's morphometry is the main cause for the accelerating of water volume lost in Lake Urmia. In particular, after 2007, lake's water temperature and density show significant variations. Water heat capacity and evaporation rate are consistent with information of lake's hypsometry.

  6. Mercury bioaccumulation in fishes from subalpine lakes of the Wallowa-Whitman National Forest, northeastern Oregon and western Idaho

    Science.gov (United States)

    Eagles-Smith, Collin A.; Herring, Garth; Johnson, Branden L.; Graw, Rick

    2013-01-01

    Mercury (Hg) is a globally distributed pollutant that poses considerable risks to human and wildlife health. Over the past 150 years since the advent of the industrial revolution, approximately 80 percent of global emissions have come from anthropogenic sources, largely fossil fuel combustion. As a result, atmospheric deposition of Hg has increased by up to 4-fold above pre-industrial times. Because of their isolation, remote high-elevation lakes represent unique environments for evaluating the bioaccumulation of atmospherically deposited Hg through freshwater food webs, as well as for evaluating the relative importance of Hg loading versus landscape influences on Hg bioaccumulation. The increase in Hg deposition to these systems over the past century, coupled with their limited exposure to direct anthropogenic disturbance make them useful indicators for estimating how changes in Hg emissions may propagate to changes in Hg bioaccumulation and ecological risk. In this study, we evaluated Hg concentrations in fishes of high-elevation, sub-alpine lakes in the Wallowa-Whitman National Forest in northeastern Oregon and western Idaho. Our goals were to (1) assess the magnitude of Hg contamination in small-catchment lakes to evaluate the risk of atmospheric Hg to human and wildlife health, (2) quantify the spatial variability in fish Hg concentrations, and (3) determine the ecological, limnological, and landscape factors that are best correlated with fish total mercury (THg) concentrations in these systems. Across the 28 study lakes, mean THg concentrations of resident salmonid fishes varied as much as 18-fold among lakes. Importantly, our top statistical model explained 87 percent of the variability in fish THg concentrations among lakes with four key landscape and limnological variables— catchment conifer density (basal area of conifers within a lake’s catchment), lake surface area, aqueous dissolved sulfate, and dissolved organic carbon. The basal area of conifers

  7. Using Satellite Imagery to Monitor the Major Lakes; Case Study Lake Hamun

    Science.gov (United States)

    Norouzi, H.; Islam, R.; Bah, A.; AghaKouchak, A.

    2015-12-01

    Proper lakes function can ease the impact of floods and drought especially in arid and semi-arid regions. They are important environmentally and can directly affect human lives. Better understanding of the effect of climate change and human-driven changes on lakes would provide invaluable information for policy-makers and local people. As part of a comprehensive study, we aim to monitor the land-cover/ land-use changes in the world's major lakes using satellite observations. As a case study, Hamun Lake which is a pluvial Lake, also known as shallow Lake, located on the south-east of Iran and adjacent to Afghanistan, and Pakistan borders is investigated. The Lake is the main source of resources (agriculture, fishing and hunting) for the people around it and politically important in the region since it is shared among three different countries. The purpose of the research is to find the Lake's area from 1972 to 2015 and to see if any drought or water resources management has affected the lake. Analyzing satellites imagery from Landsat shows that the area of the Lake changes seasonally and intra-annually. Significant seasonal effects are found in 1975,1977, 1987, 1993, 1996, 1998, 2000, 2009 and 2011, as well as, substantial amount of shallow water is found throughout the years. The precipitation records as well as drought historical records are studied for the lake's basin. Meteorological studies suggest that the drought, decrease of rainfalls in the province and the improper management of the Lake have caused environmental, economic and geographical consequences. The results reveal that lake has experienced at least two prolong dryings since 1972 which drought cannot solely be blamed as main forcing factor.Proper lakes function can ease the impact of floods and drought especially in arid and semi-arid regions. They are important environmentally and can directly affect human lives. Better understanding of the effect of climate change and human-driven changes on lakes

  8. Stable isotope and hydrogeochemical studies of Beaver Lake and Radok Lake, MacRobertson Land, East Antarctica

    International Nuclear Information System (INIS)

    Wand, U.; Hermichen, W.D.

    1988-01-01

    Beaver Lake and Radok Lake, the largest known epishelf lake and the deepest freshwater lake on the Antarctic continent, respectively, were isotopically (δ 2 H, δ 18 O) and hydrogeochemically studied. Radok Lake is an isothermal and nonstratified, i.e. homogeneous water body, while Beaver Lake is stratified with respect to temperature, salinity and isotopic composition. The results for the latter attest to freshwater (derived from snow and glacier melt) overlying seawater. (author)

  9. Outflows of groundwater in lakes: case study of Lake Raduńske Górne

    Directory of Open Access Journals (Sweden)

    Cieśliński Roman

    2014-12-01

    Full Text Available The aim of the study was to locate and describe groundwater outflows in a selected lake basin. The study hypothesis was based on the fact that, according to the specialist literature, one of the forms of lake water supply is through groundwater outflows. It was also assumed that the lakes of the Kashubian Lake District are characterised by such a form of lake water supply. The time scope of the work included the period from January 2011 to September 2012. The spatial scope of the work included the area of Lake Raduńskie Górne, located in the Kashubian Lake District in north Poland. The research plot was in the north-eastern part of the lake. Office works were aimed at gathering and studying source materials and maps. Cartographic materials were analysed with the use of the MapInfo Professional 9.5. The purpose of the field work was to find the groundwater outflows in the basin of Lake Raduńskie Górne. During the field research diving was carried out in the lake. During the dive audiovisual documentation was conducted using a Nikon D90 camera with Ikelite underwater housing for Nikon D90 and an Ikelite DS 161 movie substrobe, as well as a GoPro HD HERO 2 Outdoor camera. During the project, four groundwater outflows were found. In order to examine these springs audiovisual and photographic documentation was made. To systematise the typology of the discovered springs, new nomenclature was suggested, namely under-lake springs with subtypes: an under-lake slope spring and under-lake offshore spring

  10. Cell specific primary production and phagotrophy of phytoplankton in acidified lakes of Bohemian Forest

    Czech Academy of Sciences Publication Activity Database

    Znachor, Petr; Hrubý, P.

    2000-01-01

    Roč. 4, č. 4 (2000), s. 223-232 ISSN 1211-7420. [Acidified Lakes in the Bohemian/Bavarian Forest - History, Present and Future. České Budějovice, 21.03.2000-23.03.2000] R&D Projects: GA ČR GA206/97/0072; GA ČR GA206/98/0727; GA MŠk FRV:140/1999; GA AV ČR KSK2005601 Subject RIV: DA - Hydrology ; Limnology

  11. The importance of deciduous forest for alkalinity, phosphorus burial and isoetid macrophytes as revealed by a recent paleo study in a soft water Lobelia Lake (Grane Langsø, Denmark)

    DEFF Research Database (Denmark)

    Klamt, Anna-Marie; Reitzel, Kasper; Mortensen, Morten F.

    the deepest site of the lake. The proxies revealed diverse changes in the lake’s conditions and species composition: 1) The removal of deciduous trees seemingly reduced the calcium supply to Lake Grane Langsø and thereby the lake’s buffering capacity. This development is accompanied by decreased amounts...... of nutrient-poor soft water lakes to changes in their catchments vegetation and their partial irreversible consequences and is therefore of importance for lake management....

  12. Forest degradation and livelihood: a case study of government forest ...

    African Journals Online (AJOL)

    ... working and earning income, number of children in the household, earning income from tree crops and earning income from hunting were statistically significant factors influencing forest degradation within the study area. Therefore, the study recommends that strong and participatory forest management practices should ...

  13. Soil mesofauna in disturbed spruce forest stands near Čertovo and Plešné Lakes, the Bohemian Forest: preliminary results

    Czech Academy of Sciences Publication Activity Database

    Čuchta, Peter; Starý, Josef

    2016-01-01

    Roč. 18, April (2016), EGU2016-2978 ISSN 1607-7962. [European Geosciences Union General Assembly 2016. 17.04.2016-22.04.2016, Vienna] Institutional support: RVO:60077344 Keywords : soil mesofauna * disturbed spruce forests * Čertovo and Plešné Lakes Subject RIV: EH - Ecology, Behaviour

  14. Stable isotope and hydrogeochemical studies of Beaver Lake and Lake Radok, MacRobertson Land, East Antarctica

    International Nuclear Information System (INIS)

    Wand, U.; Hermichen, W.D.; Hoefling, R.; Muehle, K.

    1987-01-01

    Beaver Lake and Lake Radok, the largest known epishelf and the deepest freshwater lake on the Antarctic continent, respectively, were isotopically (δ 2 H, δ 18 O) and hydrogeochemically studied. Lake Radok is an isothermal and non-stratified, i.e. homogeneous water body, while Beaver Lake is stratified with respect to temperature, salinity and isotopic composition. The results for the latter attest to freshwater (derived from snow and glacier melt) overlying seawater. (author)

  15. Seasonality of freshwater bacterioplankton diversity in two tropical shallow lakes from the Brazilian Atlantic Forest.

    Science.gov (United States)

    Ávila, Marcelo P; Staehr, Peter A; Barbosa, Francisco A R; Chartone-Souza, Edmar; Nascimento, Andréa M A

    2017-01-01

    Bacteria are highly important for the cycling of organic and inorganic matter in freshwater environments; however, little is known about the diversity of bacterioplankton in tropical systems. Studies on carbon and nutrient cycling in tropical lakes suggest a very different seasonality from that of temperate climates. Here, we used 16S rRNA gene next-generation sequencing (NGS) to investigate seasonal changes in bacterioplankton communities of two tropical lakes, which differed in trophic status and mixing regime. Our findings revealed seasonally and depth-wise highly dynamic bacterioplankton communities. Differences in richness and structure appeared strongly related to the physicochemical characteristics of the water column, especially phosphate, pH and oxygen. Bacterioplankton communities were dominated by common taxonomic groups, such as Synechococcus and Actinobacteria acI, as well as rare and poorly characterized taxa such as 'Candidatus Methylacidiphilum' (Verrucomicrobia). Stratification and oxygen depletion during the rainy season promoted the occurrence of anoxygenic phototrophic and methanotrophic bacteria important for carbon and nutrient cycling. Differences in lake mixing regime were associated with seasonal beta diversity. Our study is the first attempt to use NGS for cataloging the diversity of bacterioplankton communities in Brazilian lakes and thus contributes to the ongoing worldwide endeavor to characterize freshwater lake bacterioplankton signatures. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. A preliminary study on sedimentation rate in Tasek Bera Lake estimated using Pb-210 dating technique

    International Nuclear Information System (INIS)

    Wan Zakaria Wan Muhamad Tahir; Johari Abdul Latif; Juhari Mohd Yusof; Kamaruzaman Mamat; Gharibreza, M.R.

    2010-01-01

    Tasek Bera is the largest natural lake system (60 ha) in Malaysia located in southwest Pahang. The lake is a complex dendritic system consisting of extensive peat-swamp forests. The catchment was originally lowland dipterocarp forest, but this has nearly over the past four decades been largely replaced with oil palm and rubber plantations developed by the Federal Land Development Authority (FELDA). Besides the environmentally importance of Tasek Bera, it is seriously subjected to erosion, sedimentation and morphological changes. Knowledge and information of accurate sedimentation rate and its causes are of utmost importance for appropriate management of lakes and future planning. In the present study, environmental 210 Pb (natural) dating technique was applied to determine sedimentation rate and pattern as well as the chronology of sediment deposit in Tasek Bera Lake. Three undisturbed core samples from different locations at the main entry and exit points of river mouth and in open water within the lake were collected during a field sampling campaign in October 2009 and analyzed for 210 Pb using gamma spectrometry method. Undisturbed sediments are classified as organic soils to peat with clayey texture that composed of 93 % clay, 5 % silt, and 2 % very fine sand. Comparatively higher sedimentation rates in the entry (0.06-1.58 cm/ yr) and exit (0.05-1.55 cm/ yr) points of the main river mouth as compared to the lakes open water (0.02- 0.74 cm/ yr) were noticed. Reasons for the different pattern of sedimentation rates in this lake and conclusion are discussed in this paper. (author)

  17. FOREST ECOSYSTEMS AND GLOBAL CHANGE: THE CASE STUDY OF INSUBRIA

    Directory of Open Access Journals (Sweden)

    M. Pautasso

    2013-03-01

    Full Text Available Forest ecosystems face multiple challenges due to climate change, invasive species, urbanization, land use change and the interactions between these global change drivers. This review provides an overview of such challenges for the case study of Insubria. Insubria is a region on the Southern side of the European Alps, famous for its stunning lakes (e.g., Como, Garda, Lugano, Maggiore, blessed by a relatively mild and humid climate, and shaped by the geologic fault line between the African and European plates. Global change impacts in Insubria pose a threat to its biodiversity and chestnut woodlands, particularly through modified winter forest fire regimes. Insubric biodiversity conservation, in turn, is essential to counteract the effects of climate change. Sustainable management of Insubric forests is made more difficult by rural abandonment, air pollution and invasive exotic species. There is a need to develop reliable long-term bio-indicators and to predict the shift of Insubric species, ecosystems and tree-lines due to rapid climate changes. Insubric studies on forests and global change call for enhanced international collaboration in forest management and research. Interdisciplinary approaches are needed to move from studies of single global change drivers to experiments, scenarios and models taking into account their combination and our responses to global change.

  18. Partitioning the impact of environmental factors on lake concentrations and catchment budgets for base cations in forested ecosystems

    International Nuclear Information System (INIS)

    Augustin, Fougère; Houle, Daniel; Gagnon, Christian; Couture, Suzanne; Courchesne, François

    2015-01-01

    Highlights: • We examine base cation budgets (BC Q ) and concentrations (BC C ) in forested catchments. • Climate is the most important driver of BC Q and BC C in the study area. • We develop multivariate models that explain up to 69% of variation in BC C and BC Q . - Abstract: Seventy-two forested lake catchments were studied in Quebec (Canada) to examine the influence of climate, atmospheric deposition and catchment characteristics on base cation (BC) concentrations in lake waters (BC C ) and base cation budgets at the catchment scale (BC Q ). The catchments are located along a bioclimatic gradient in a vast (180 000 km 2 ) study area underlained by the Canadian Shield. Multivariate statistical approaches are used to simultaneously assess the effects of multiple environmental factors on cation fluxes. Mean annual BC C were 132, 40, 24 and 7 μmol c l −1 for Ca, Mg, Na and K, respectively. Mean annual BC Q estimates showed exports of 0.826, 0.251, 0.135 and 0.043 kmol c ha −1 an −1 for Ca, Mg, Na and K, respectively. There were strong similarities in the spatial variation of BC C and BC Q , and also in their links with environmental factors. We hypothesized that the spatial variability of both, BC C and BC Q , were strongly influenced by the spatial variability in the rates of mineral weathering reactions. Variance partitioning indicated that climate-related effects accounted for 51.6% and 52.7% of the variation in BC Q and BC C , respectively. Nonetheless, lake/catchment morphometry and variables linked to solutes sources (lithology, atmospheric deposition and soil properties) were also included in some models. Overall, BC C and BC Q were positively affected by temperature, precipitation as rain and sulphate depositions, and negatively influenced by precipitation as snow and the number of frost days. Multivariate models explaining up to 69% of variation in BC C and BC Q were developed. This study shows the strong impact of climatic drivers on base

  19. Variability of the water availability in a river lake system – A case study of Lake Symsar

    Directory of Open Access Journals (Sweden)

    Kuriata-Potasznik Angela B.

    2016-12-01

    Full Text Available It is predicted that climate change will result in the diminution of water resources available both on global and regional scales. Local climate change is harder to observe and therefore, while counteracting its effects, it seems advisable to undertake studies on pertinent regional and local conditions. In this research, our aim was to assess the impact of a river and its catchment on fluctuations in the water availability in a natural lake which belongs to a post-glacial river and lake system. River and lake systems behave most often like a single interacting hydrological unit, and the intensity of water exchange in these systems is quite high, which may cause temporary water losses. This study showed that water in the analyzed river and lake system was exchanged approx. every 66 days, which resulted from the total (horizontal and vertical water exchange. Also, the management of a catchment area seems to play a crucial role in the local water availability, as demonstrated by this research, where water retention was favoured by wooded and marshy areas. More intensive water retention was observed in a catchment dominated by forests, pastures and wetlands. Wasteland and large differences in the land elevation in the tested catchment are unfavourable to water retention because they intensify soil evaporation and accelerate the water run-off outside of the catchment. Among the actions which should be undertaken in order to counteract water deficiencies in catchment areas, rational use and management of the land resources in the catchment are most often mentioned.

  20. Forest-fire behavior studies

    Science.gov (United States)

    J.R. Curry; W.L. Fons

    1940-01-01

    General principles of forest management were established over 200 years ago in Central Europe and the task of the American forester has been largely to adapt these principles to the management of the vast, rough, and inaccessible natural forests of this country. A series of essentially new problems has arisen, however. In the humid climate where forestry originated,...

  1. Modelling reversibility of Central European mountain lakes from acidification: Part I - the Bohemian forest

    Directory of Open Access Journals (Sweden)

    V. Majer

    2003-01-01

    Full Text Available A dynamic, process-based acidification model, MAGIC7, has been applied to three small, strongly acidified lakes in the Bohemian Forest, the Czech Republic. The model was calibrated for a set of experimental records on lake water composition over the 1984–2000 period, and produced hindcast concentrations that compared well, even with older (40-year irregular determinations of nitrate, chloride and pH. Water and soil chemistry forecasts up to 2050 were based on reductions in S and N emissions presupposed by the Gothenburg Protocol. Modelled sulphate and chloride concentrations were predicted to decrease to the levels at the beginning of the 20th century by 2050. The lake water carbonate buffering system is predicted to be re-established in only two lakes (Cerné and Plešné, with current soil base saturations of 12-15%. Concentrations of ionic aluminium species decreased sharply, from 110 μeq l-1 in the mid-1980s to the current ~40 μeq l-1, and were predicted to decrease below 10 μeq l-1 in the 2020s. Diatom-inferred pH in pre-industrial times was substantially lower than modelled pH. It is suggested that the diatom pH, based almost entirely on non-planktonic species, is biased by inwash of diatoms from more acidic tributaries into the sediment of these small lakes. Generally significant results can be summarised as follows: (1 Simulated sulphate levels agree well with observations during acidification progress and retreat only for values of soil SO42- adsorption capacity three to six times (20 to 40 μeq kg-1 higher than those found experimentally. This implies a further mechanism of S retention and release in addition to physical sulphate adsorption to Fe and Al oxides of soils. (2 The catchments’ ability to retain deposited N appeared to decline after ~1950 but this was not connected with a sufficient change in the C:N ratio of the soils. Agreement between modelled and observed concentrations of nitrate was therefore achieved by

  2. Holocene vegetation dynamics of Taiga forest in the Southern Altai Mountains documented by sediments from Kanas Lake

    Science.gov (United States)

    Huang, X.; Chen, F.

    2016-12-01

    The Chinese Altai is the southern limit of the Taiga forest of the continent, and regional vegetation dynamics during the Holocene will help us to understand regional climate changes, such as the Siberian High variations. Here we present a pollen-based vegetation and climate reconstruction from a well dated sediment core from Kanas Lake, a deep glacial moraine dammed lake in the Southern Altai Mountains (Chinese Altai). The 244-cm-long sequence spans the last 13,500 years, and the chronology is based on nine accelerator mass spectrometry radiocarbon dates from terrestrial plant macrofossils. At least five stages of regional vegetation history are documented: (i) From 13.5 to 11.7 ka (1 ka = 1000 cal yr BP), Kanas Lake region was occupied by steppe dominated by Artemisia, Chenopodiaceae and grass pollen, with low tree coverage. (ii) From 11.7 to 8.5 ka, regional forest build up dramatically indicated by increasing tree pollen percentages, including Picea, Larix, and the highest Junipers, with decreasing Artemisia and increasing Chenopodiaceae. (iii) From 8.5 to 7.2 ka, the forest around the lake became dense with the maximum content of Picea and Betula pollen types. And the steppe pollen types reached their lowest values. (iv) From 7.2 to 4 ka, as a typical tree species of Taiga forest, Larix pollen percentage became much higher than previous stage, and the sum of trees & shrubs pollen types decreased, which possibly indicated cooler and wetter climate (v) After 4 ka, trees & shrubs (e.g. Betula, Junipers) pollen types decreased, with increasing Artemisia and decreasing Chenopodiaceae, which might indicated more humid and cooler climate in the late Holocene. Comparing to the other pollen records in the Altai Mountains, Lake Grusha and Lake Hoton had recorded a slightly different process of vegetation evolution in the early Holocene, where forest was built up in the northern side of the Chinese Altai faster than that of the Kanas Lake area. And the difference could

  3. Looking Back to Move Forward: Collaborative Planning to Revise the Green Mountain and Finger Lakes National Forests Land and Resource Management Plans

    Directory of Open Access Journals (Sweden)

    Michael J Dockry

    2015-07-01

    Full Text Available The United States Department of Agriculture Forest Service (Forest Service manages 154 national forests and 20 grasslands in 44 states and Puerto Rico. National Forest Land and Resource Management Plans (forest plans form the basis for land and resource management of national forests in the United States. For more than a decade the Forest Service has been attempting to incorporate innovative, collaborative public involvement strategies into the process for revising forest plans. In 2012 and 2015 the Forest Service codified new regulations for developing, revising, and amending forest plans. Collaboration and public involvement are explicit goals of the new regulations. This paper briefly reviews the literature on collaborative planning on national forests and explores a successful collaborative planning process used by the Green Mountain and Finger Lakes National Forests, located in Vermont and New York respectively, to develop their 2006 forest plans. This paper shows how the Green Mountain and Finger Lakes National Forests developed parallel public and internal collaborative processes to build trust, relationships, and partnership, and discusses the implications for process design, capacity building, and facilitating agreements. By looking back at this successful case of collaborative forest planning, key lessons can provide ideas for developing collaborative processes for future planning efforts.

  4. Eco-Hydrology From Space: How Satellites Can Be Harnessed To Assess Human Impacts On The Trophic Status Of Lakes In Forested Landscapes

    Science.gov (United States)

    Sass, G. Z.; Creed, I. F.; Prairie, Y. T.

    2009-05-01

    The recent proliferation of spatially and temporally extensive geospatial datasets (e.g., Radarsat, Landsat) has created research opportunities into the characterization of eco-hydrological processes and patterns across Canada's vast forests. Herein, we demonstrate how these space based sensors can be used to establish the hydrologic controls on the range of natural variability (RNV) of lake trophic status and to assess thresholds in disturbance related to human activities that lead to the exceedance in RNV (i.e., lake trophic status that is outside the RNV). We focus on two lake districts in the boreal forest. One is on the western Boreal Plain, where average annual precipitation (P) is less than potential evapotranspiration (PET) (PPET and hydrology is characterized by simpler surface hydrologic dynamics. In each of these lake districts, we use Radarsat and Landsat imagery to map surface/near surface hydrologic flow paths (the conveyors of nutrients to and from lakes) and lake trophic status. We establish the RNV of trophic status in landscapes with minimal human presence and compare this to the trophic status of lakes where there is a significant human footprint caused by forest management activities. By building statistical models that account for differences in climate and hydrologic pathways within basins contributing to a lake, we are able to evaluate how much disturbance in forest hydrology is needed to result in a fundamental change in nutrient loading to the lakes and ultimately lake trophic status. We conclude that satellite sensors can assist in the establishment of realistic reference conditions against which effects of forest management activities on lake trophic status can be assessed and management targets can be established.

  5. Value Assessment of Artificial Wetland Derived from Mining Subsided Lake: A Case Study of Jiuli Lake Wetland in Xuzhou

    OpenAIRE

    Laijian Wang; Lachun Wang; Pengcheng Yin; Haiyang Cui; Longwu Liang; Zhenbo Wang

    2017-01-01

    Mining subsided lakes are major obstacles for ecological restoration and resource reuse in mining regions. Transforming mining subsided lakes into artificial wetlands is an ecological restoration approach that has been attempted in China in recent years, but a value assessment of the approach still needs systematic research. This paper considers Jiuli Lake wetland, an artificial wetland derived from restoration of a mining subsided lake in plain area, as a case study. A value assessment model...

  6. The consequences of changes in forest land cover in the Alpine and Jurassic massifs on the physico-chemical status of deep lake waters

    Directory of Open Access Journals (Sweden)

    Rachid Nedjai

    2012-02-01

    Full Text Available The issue of acidification in lake waters has been the topic of numerous scientific studies in northern Europe and North America. In recent years, interest in the topic has spread to southern Europe and Asia because similar symptoms have been observed (drop in pH and in redox potential, generally accompanied by oxygen depletion. All the scientific work on the issue has concluded that the phenomenon is general and affects, to different degrees, lakes located at low to medium altitudes in mountains (the Vosges mountains and more recently the Jura mountains, in France. The difference in degree is often interpreted as the result of different combinations from three sources, namely acid rain, direct discharges of pollutants and the spread of forests (essentially conifer species. The first two sources have been confirmed, but the third is less perceptible due to slow progression of the phenomenon.Analysis and modelling of changes in land cover in the Hérisson river basin in the Jura mountains (largely carbonated soils confirmed the direct impact of the forest cover on the physico-chemical quality of lake waters, in particular at the deeper levels (hypolimnion over the past 30 years. The impact is reinforced by the considerable presence of peat zones around the lakes which, during high-water periods, contribute large quantities of dissolved, particulate organic matter.The goal of this work is to show the direct impact of the increasing forest cover observed on the Jurassic plateaus, caused by a considerable reduction in farming activity over the past 30 years. This work focuses on an analysis of land cover (vegetation, using four satellite images spanning the period from 1975 to 2006, and calls on hydrogeochemical modelling (WARMF to evaluate changes in the physico-chemical quality, i.e. acidification, of deep lake waters. This first step is followed by a predictive phase prior to measuring the intensity of the physico-chemical changes (pH and redox

  7. Assessing naturalness in northern great lakes forests based on historical land-cover and vegetation changes.

    Science.gov (United States)

    Gimmi, Urs; Radeloff, Volker C

    2013-08-01

    The concept of naturalness was developed to assess to what degree landscapes represent a natural state. Protected areas are often regarded as the remnants of untouched landscapes although many landscapes commonly perceived as pristine have a long history of human impact. Here, we introduced a historical perspective into the concept of naturalness and the analysis of the effectiveness of protected areas by analyzing historical trajectories in land-cover and forest communities for the Pictured Rocks National Lakeshore on Michigan's Upper Peninsula (USA). Distribution of land-cover and forest community types was reconstructed for pre-settlement time (around 1850), the height of agricultural expansion (1928), and modern conditions (2000). Naturalness of the landscape was assessed by analyzing similarity between pre-settlement and current conditions and by assessing landscape continuity (1850-1928-2000). We compared changes in the strictly protected park core zone with those in the inland buffer zone with ongoing sustainable logging, and a not protected area adjacent to the park. Forest was the dominant land-cover type over the entire study period. We detected a gradient in land-cover continuity from the core zone (81 % continuity) to the inland buffer zone (74 %) and the area outside the park (66 %). Northern hardwood was the dominating forest type in all time points with high continuity (76 %). In contrast, pine forests show a more dynamic pattern with more than 50 % of the initial forests switching to non-forest or early succession forest types by 1928. More than half of the study area was considered as "natural virgin" (no changes in land-cover and forest community type) with a higher portion within the park than in the adjacent area. In contrast, areas with low naturalness are more abundant outside the park. Our study demonstrates the value of integrating historical information into naturalness assessments and the results provide useful information for future

  8. Great Salt Lake basins study unit

    Science.gov (United States)

    Waddell, Kidd M.; Baskin, Robert L.

    1994-01-01

    In 1991, the U.S. Geological Survey (USGS) began implementing a full-scale National Water-Quality Assessment (NAWQA) Program.The long-term goals of the NAWQA Program are to describe the status and trends in the quality of a large, representative part of the Nation’s surface- and ground-water resources and to provide a sound, scientific understanding of the primary natural and human factors that affect the quality of these resources. In meeting these goals, the program will produce a wealth of water-quality information that will be useful to policy makers and managers at Federal, State, and local levels.A major design feature of the NAWQA Program will enable water-quality information at different areal scales to be integrated. A major component of the program is study-unit investigations, which ae the principal building blocks of the program upon which national-level assessment activities will be based. The 60 study-unit investigations that make up the program are hydrologic systems that include principal river basins and aquifer systems throughout the Nation. These study units cover areas from less than 1.000 to greater than 60,000 mi2 and incorporate from about 60 to 70 percent of the Nation’s water use and population served by public water supply. In 1993, assessment activities began in the Great Salt Lake Basins NAWQA study unit.

  9. Change detection studies in and around Kolleru Lake using high resolution data

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, M.V.; Rao. K.H.; Ramana, I.V.; Sasamal, S.K.; Choudhury, S.B.; Bhan, S.K.

    under fish pond culture within the lake area using high resolution data from satellites. The changes that are occurred during the last ten years in Kolleru lake area have been studied. The digital base map covering the lake and surroundings...

  10. To Conserve or not to Conserve: A case study of Forest Valuation of Tinderet Natural Forest

    International Nuclear Information System (INIS)

    Lang'at, D.; Cheboieo, J.; Siko, R

    2007-01-01

    Tinderet natural forest is part of the extensive Mau complex and forms an important hydrological system for lake Victoria. Information on on economic values of most forests in Kenya are not available or scanty. This paper aims at estimating the total economic value of Tinderet forest. Surveys were conducted on 109 households sampled from three villages within five kilometers of the forest. Further information/data was to determine direct use values. Other indirect use values (carbon sequestration and soil conservation) were were estimated by use of secondary data where the data not available, benefit transfer method was adopted. It was established that, the annual direct use of value to forest adjacent households is about Ksh. 33 million. The indirect use value is estimated at Ksh. 270 million and this value accrues to global community and not restricted to Kenya. The opportunity cost of conserving the Tinderet natural forest is estimated at Ksh. 210 million and only about Ksh. 33 million per year accrue as direct use values to the whole community. The current benefit from forest is inadequate to offset the community cost of of leaving the forest in it's present state. Based on this analysis, the government and the local communities are subsidizing the retention of the forest and this subsidy is currently estimated at at Ksh. 67 million through lost opportunity in settlement and income. In order to promote positive attitudes of the community adjustment to the forest on sustainable use of the forest, consumptive use of the forest should be encouraged

  11. Evaluation of Water Quality in Shallow Lakes, Case Study of Lake Uluabat

    Directory of Open Access Journals (Sweden)

    Saadet İLERİ

    2014-04-01

    Full Text Available Lake Uluabat, located 20 km south of the Marmara Sea, between 42° 12' North latitude, 28° 40'East longitude and is located in the province of Bursa. The Lake is one of the richest lakes in terms of aquatic plants besides fish and bird populations in Turkey. In this study, water quality of the Lake was monitored from June 2008 to May 2009 during the 12 month period with the samples taken from 8 points in the lake and spatial and temporal variations of the parameters were examined. pH, temperature (T, electrical conductivity (EC, dissolved oxygen (DO, suspended solids (SS, secchi depth (SD, water level (WL, nitrate nitrogen (NO3-N, total nitrogen (TN, phosphate-phosphorus (PO4-P, total phosphorus (TP, alkalinity, chemical oxygen demand (COD and chlorophyll-a (Chl-a were the monitoring parameters. As a result, concentrations of the parameters were found at high levels especially the 1st, 4th, 5th, and 8th stations and temporally were found at high levels often in the summer. According to the results of analysis of variance, regional and temporal variations of all parameters were found important except SS and NO3-N

  12. Lake Orta: a case study (Part 1

    Directory of Open Access Journals (Sweden)

    Renato BAUDO

    2001-02-01

    Full Text Available Preface The extraordinary case of industrial pollution in Lake Orta was followed and documented by the Istituto Italiano di Idrobiologia from its very origin in 1926. Many papers were published regarding the effects of the pollution on chemistry and biology of the lake but they were scattered in various scientific journals and in a long time period. Now the time has come to draw the conclusions of our long work and the long history of the lake. We planned to publish a monographic volume, but technical reasons made it impossible to realise this project. The papers which could have formed the volume will be splitted into issues 60(1 and 60(2 of Journal of Limnology.

  13. Drought drove forest decline and dune building in eastern upper Michigan, USA, as the upper Great Lakes became closed basins

    Science.gov (United States)

    Loope, Walter L.; Loope, Henry M.; Goble, Ronald J.; Fisher, Timothy G.; Lytle, David E.; Legg, Robert J.; Wysocki, Douglas A.; Hanson, Paul R.; Young, Aaron R.

    2012-01-01

    Current models of landscape response to Holocene climate change in midcontinent North America largely reconcile Earth orbital and atmospheric climate forcing with pollen-based forest histories on the east and eolian chronologies in Great Plains grasslands on the west. However, thousands of sand dunes spread across 12,000 km2 in eastern upper Michigan (EUM), more than 500 km east of the present forest-prairie ecotone, present a challenge to such models. We use 65 optically stimulated luminescence (OSL) ages on quartz sand deposited in silt caps (n = 8) and dunes (n = 57) to document eolian activity in EUM. Dune building was widespread ca. 10–8 ka, indicating a sharp, sustained decline in forest cover during that period. This decline was roughly coincident with hydrologic closure of the upper Great Lakes, but temporally inconsistent with most pollen-based models that imply canopy closure throughout the Holocene. Early Holocene forest openings are rarely recognized in pollen sums from EUM because faint signatures of non-arboreal pollen are largely obscured by abundant and highly mobile pine pollen. Early Holocene spikes in nonarboreal pollen are recorded in cores from small ponds, but suggest only a modest extent of forest openings. OSL dating of dune emplacement provides a direct, spatially explicit archive of greatly diminished forest cover during a very dry climate in eastern midcontinent North America ca. 10–8 ka.

  14. Hydrochemical and isotope study of Lake Titicaca

    International Nuclear Information System (INIS)

    Gonfiantini, R.; Cioni, R.; Paredes, M.

    2002-01-01

    The chemical and isotopic compositions of Lake Titicaca and its inflow waters (precipitation, tributaries, groundwater) were determined with the aim of establishing the lake chemical and isotope balance. The three main regions of the lake, i.e. the Lago Mayor, the eastern and the western basins of Lago Menor, connected in cascade, show significant chemical and isotopic differences. Chloride and sodium balance indicates that an average of about 92% of the inflow water evaporates, and the remaining 8 % is lost through Rio Desaguadero and infiltration. The balance of each basin is also obtained, including the inter-basin fluxes. The stable isotope balance in not possible because no data are available on the mean atmospheric vapour isotopic composition. However, this was tentatively computed using the fluxes obtained from chemistry. The vapour δ-values are slightly more negative than those of rainfall. Tritium, noble gases and chloro-fluoro-carbons in vertical profiles show that the lake is vertically well mixed and there is no water segregation at depth. (author)

  15. Panama Lakes Water Quality Modeling Study

    National Research Council Canada - National Science Library

    Bunch, Barry

    2003-01-01

    .... The canal has a length of 30 km and is capable of traversing vessels up to 294 m long with maximum drafts of 12 m Most portions of the canal are above sea level in a man-made reservoir, Gatun Lake...

  16. Vertical distribution of 137Cs in lake sediments in post-Chernobyl period

    International Nuclear Information System (INIS)

    Gorgun, T.V.; Putyrskaya, V.V.; Klemt, E.; Goncharova, N.V.

    2011-01-01

    The vertical distribution of 137 Cs was studied in one of the glacial lakes situated in the region of Tuchola Forest National Park (Poland). Radiocaesium was used for sedimentation rates estimation and dating of the sediment layers of the lake.

  17. Relationship between Normalized Difference Vegetation Index by Ground Observations and Evapotranspiration at Forested Areas on the Lake Biwa Project.

    Science.gov (United States)

    Ebisu, N.; Nishikawa, A.; Kondho, A.; Nakakita, E.; Tanaka, K.

    2001-12-01

    Knowledge of relationship between normalized difference vegetation index (NDVI) and evapotranspiration is essential in order to estimate distribution of evapotranspiration at wide forest areas using satellite remote sensing. The relationship between NDVI and evapotranspiration was examined by the ground observation method of NDVI on the Lake Biwa Project. The Lake Biwa Project has been developed and proceeded by a Japanese group for investigating the hydrological cycle near land surface in and over the Lake Biwa Basin, which is composed of tens of members from about twenty universities, institutions and consulting companies. This NDVI values on the ground observation is calculated by reflected solar radiation and photosynthetic photon flux using a pyranometer and a quantum sensor. From the result of the observation at a forest experimental site, it was found that the seasonal variations of NDVI by ground observations corresponded to NDVI calculated from Landsat TM data. The research examines the relationship among NDVI and seasonal changes of evapotranspiration, leaf area index (LAI), and canopy resistance of Penman-Monteith method. The results indicate that the correlation coefficient between NDVI and LAI was high (r=0.71) and NDVI was not correlated to evapotranspiration and moving average of canopy resistance. However, high correlation was found between NDVI and the maximum values of evapotranspiration (r=0.82) for each 14-day periods and canopy resistance (r=0.79) was also correlated to NDVI at that time.

  18. Relationships between physico-chemical and microbiological parameters in the monimolimnion of a forest meromictic lake

    Directory of Open Access Journals (Sweden)

    Dorota Górniak

    2014-05-01

    Full Text Available The small meromictic Lake Zapadłe in North-Eastern Poland was the subject of our research in the vegetation period between April and November. Our study were to aim a better recognition of meromixis phenomenon and find connections between hydrochemical and microbiological parameters. Here, the monimolimnion layer was below 10 m depth with the chemocline between 13-14 m. Highly significant Spearman’s ranks correlations of P<0.05 were found between conductivity and biochemical oxygen demand (0.91, ammonium nitrogen (0.96, phosphate (0.91, iron (0.77 and manganese (0.82. Favourable conditions for bacterioplankton growth and function here included; the absence of water circulation, the presence of anaerobic conditions and hydrogen sulphide, a constant water temperature and highly significant correlations between total bacterial counts (TBC, bacterial biomass (BB and biochemical oxygen demand (BOD, conductivity, total organic carbon (TOC and dissolved organic carbon (DOC. The pool of bacteria-forming biomass increased significantly in the lower part of the monimolimnion. A highly significant correlation (P<0.05 existed between bacterial biomass (BB and their anaerobic metabolic products: ammonium (r=0.75, hydrogen sulphide (r=0.45 and phosphate (r=0.68 anaerobic metabolic products. This correlation indicated the significant proportion of anaerobic sulfate-reducing bacteria. The impact of physico-chemical parameters on bacterioplankton biomass during the June-November growth season was clearly illustrated in the correspondence canonical analysis (CCA. This recorded its greatest mass at 15 to 17 metres above the lake bed. Although no clear seasonal variations were noted in bacterioplankton composition described by Denaturing Gradient Gel Electrophoresis (DGGE. The monimolimnion lake layer contained 46 Operational Taxonomic Units (OTUs. Subsequent comparison of the upper and lower minimolimnion layers showed 37 of these OTUs were common, while 5 were

  19. NATIONAL SEISMIC, RADAR AND SEISMOLOGICAL STUDIES OF SUBGLACIAL LAKE VOSTOK

    Directory of Open Access Journals (Sweden)

    S. V. Popov

    2012-01-01

    Full Text Available The results of the remote sensing which carried out in the LakeVostokarea are discussed in the paper. A.P. Kapitsa and O.G. Sorokhtin started the geophysical researches in this area in 1950s. Satellite altimetry data, which analyzed in 1990s yielded to the discovering of the LakeVostok. After that, PMGE and RAE started the systematic studying of this natural phenomenon by seismic and radio-echo sounding. Total, 318 seismic soundings and 5190 kmof the radio-echo profiles has been collected by 2008. Special precise measurements which carried out in the 5G-1 borehole vicinity are resulted in the ice thickness over Vostok Station is 3760±30 mby seismic and 3775±15 mby radio-echo sounding. Thus, the error of geophysical measurements is less than 0.3%. The Russian investigations are resulted in definition the border of the lake, the discovering of 56 subglacial water caves around the lake and compilation the maps including ice thickness, ice base and bedrock topography and the depth of the lake. Average depth of the LakeVostokis about 400 m; water volume is 6100 km3. After 2008, the remote sensing works have been concentrated to the studying of the bottom sediments by refraction seismic technique. The firsts result shown that the bottom sediments thickness varies from 400 to1200 m.

  20. Geophysical and Hydrologic Studies of Lake Seepage Variability.

    Science.gov (United States)

    Toran, Laura; Nyquist, Jonathan; Rosenberry, Donald; Gagliano, Michael; Mitchell, Natasha; Mikochik, James

    2015-01-01

    Variations in lake seepage were studied along a 130 m shoreline of Mirror Lake NH. Seepage was downward from the lake to groundwater; rates measured from 28 seepage meters varied from 0 to -282 cm/d. Causes of this variation were investigated using electrical resistivity surveys and lakebed sediment characterization. Two-dimensional (2D) resistivity surveys showed a transition in lakebed sediments from outwash to till that correlated with high- and low-seepage zones, respectively. However, the 2D survey was not able to predict smaller scale variations within these facies. In the outwash, fast seepage was associated with permeability variations in a thin (2 cm) layer of sediments at the top of the lakebed. In the till, where seepage was slower than that in the outwash, a three-dimensional resistivity survey mapped a point of high seepage associated with heterogeneity (lower resistivity and likely higher permeability). Points of focused flow across the sediment-water interface are difficult to detect and can transmit a large percentage of total exchange. Using a series of electrical resistivity geophysical methods in combination with hydrologic data to locate heterogeneities that affect seepage rates can help guide seepage meter placement. Improving our understanding of the causes and types of heterogeneity in lake seepage will provide better data for lake budgets and prediction of mass transfer of solutes or contaminants between lakes and groundwater. © 2014, National Ground Water Association.

  1. Geophysical study of the Clear Lake region, California

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, R.H.

    1975-01-01

    Results of geophysical studies in the Clear Lake region of California, north of San Francisco, have revealed a prominent, nearly circular negative gravity anomaly with an amplitude of more than 25 milligals (mgal) and an areal extent of approximately 250 square miles and, in addition, a number of smaller positive and negative anomalies. The major negative gravity anomaly is closely associated with the Clear Lake volcanic field and with an area characterized by hot springs and geothermal fields. However, the anomaly cannot be explained by mapped surface geologic features of the area. Aeromagnetic data in the Clear Lake region show no apparent correlation with the major negative gravity anomaly; the local magnetic field is affected principally by serpentine. An electrical resistivity low marks the central part of the gravity minimum, and a concentration of earthquake epicenters characterizes the Clear Lake volcanic field area. The primary cause of the major negative gravity anomaly is believed to be a hot intrusive mass, possibly a magma chamber, that may underlie the Clear Lake volcanic field and vicinity. This mass may serve as a source of heat for the geothermal phenomena in the area. Other smaller gravity anomalies in the Clear Lake region are apparently caused by near-surface geologic features, including relatively dense units of the Franciscan Formation and less dense Cenozoic sedimentary and volcanic rock units.

  2. Geophysical and hydrologic studies of lake seepage variability

    Science.gov (United States)

    Toran, Laura; Nyquist, Jonathan E.; Rosenberry, Donald O.; Gagliano, Michael P.; Mitchell, Natasha; Mikochik, James

    2014-01-01

    Variations in lake seepage were studied along a 130 m shoreline of Mirror Lake NH. Seepage was downward from the lake to groundwater; rates measured from 28 seepage meters varied from 0 to −282 cm/d. Causes of this variation were investigated using electrical resistivity surveys and lakebed sediment characterization. Two-dimensional (2D) resistivity surveys showed a transition in lakebed sediments from outwash to till that correlated with high- and low-seepage zones, respectively. However, the 2D survey was not able to predict smaller scale variations within these facies. In the outwash, fast seepage was associated with permeability variations in a thin (2 cm) layer of sediments at the top of the lakebed. In the till, where seepage was slower than that in the outwash, a three-dimensional resistivity survey mapped a point of high seepage associated with heterogeneity (lower resistivity and likely higher permeability). Points of focused flow across the sediment–water interface are difficult to detect and can transmit a large percentage of total exchange. Using a series of electrical resistivity geophysical methods in combination with hydrologic data to locate heterogeneities that affect seepage rates can help guide seepage meter placement. Improving our understanding of the causes and types of heterogeneity in lake seepage will provide better data for lake budgets and prediction of mass transfer of solutes or contaminants between lakes and groundwater.

  3. Forest Service National Forest System perceptions of law enforcement and investigations: nationwide study

    Science.gov (United States)

    Deborah J. Chavez; Joanne F. Tynon

    2008-01-01

    This is the fifth in a series of studies to evaluate perceptions of the roles, responsibilities, and issues entailed in the jobs of U.S. Department of Agriculture Forest Service law enforcement and investigations (LEI) personnel. An e-mail survey was administered to the 537 Forest Service forest supervisors and district rangers (National Forest System [NFS] line...

  4. A Numerical Case Study of the Implications of Secondary Circulations to the Interpretation of Eddy-Covariance Measurements Over Small Lakes

    Science.gov (United States)

    Kenny, William T.; Bohrer, Gil; Morin, Timothy H.; Vogel, Chris S.; Matheny, Ashley M.; Desai, Ankur R.

    2017-11-01

    We use a large-eddy simulation (LES) to study the airflow patterns associated with a small inland lake surrounded by a forest of height one-tenth the radius of the lake. We combine LES results with scalar dispersion simulations to model potential biases in eddy-covariance measurements due to the heterogeneity of surface fluxes and vertical advection. The lake-to-forest transition can induce a non-zero vertical velocity component, affecting the interpretation of flux measurements. Significant horizontal gradients of mean CO2 concentration are generated by the forest carbon sink and lake carbon source, which are transported by local roughness-induced circulation. We simulate six hypothetical locations for flux towers along a downwind gradient at various heights, and calculate at each location the effects of both the average vertical advection and average turbulent-flux divergence of CO2. We compare our model results with an analytical footprint model to find that the footprint predicted by the analytical model is inaccurate due to the complexities of advection for our test case. Similar small lakes surrounded by forests are likely affected by these phenomena as well. We recommend specialized levelling of sonic anemometers to reduce the effects of non-zero wind components. Flux towers over small water bodies should be constructed at a distance 0.5-0.67 times the diameter of the lake to provide ample separation from the areas affected by the rotor effect of the upwind forest/lake transition and the updraft at the downwind edge. Finally, we also suggest the filtering of wind directions based on the Higgins ratio.

  5. Effects of climate, fire and vegetation development on Holocene changes in total organic carbon concentration in three boreal forest lakes in northern Sweden

    Directory of Open Access Journals (Sweden)

    P. Rosén

    2007-11-01

    Full Text Available Near infrared spectroscopy (NIRS, diatoms, pollen, charcoal, loss-on-ignition (LOI, and nutrient elements in lake sediments were used to assess important factors controlling Holocene changes in the total organic carbon (TOC concentration, pCO2, color and pH of lake water in three boreal forest lakes in northern Sweden. The results suggest that mire formation, fire frequency and humidity are the most important forcing factors on millennial timescales. Mires produce humic acids that become available to the lakes, whereas fires may reduce the pool of carbon in the catchments, and humidity controls the transportation of allochthonous carbon into the lakes. Vegetation development and temperature as sole factors are of minor importance for the TOC concentrations in these lakes on a millennial timescale. Two of the sites indicate that liming and possibly fish introduction and rotenone treatment in recent time has led to increased TOC, color and pH in the lake water, and changed the diatom community composition to an assemblage that has never been present before. Given the predicted climate change scenario that suggests a more humid climate, expanding mires and less frequent fires, our paleolimnological data suggest that TOC concentrations can be expected to increase in boreal forest lakes in the future. Since super-saturation and emission of CO2 from lakes is correlated to the TOC concentration of lake water, higher TOC concentrations may lead to increased emission of CO2 from lakes to the atmosphere.

  6. Comparison of groundwater quality from forested (Waimarino River), urban (Turangi), and natural wetland (South Taupo Wetlands) subcatchments at the southern end of Lake Taupo

    International Nuclear Information System (INIS)

    Rosen, M.R.; Reeves, R.R.; Eser, P.; Chague-Goff, C.; Coshell, L.

    1998-01-01

    Comparison of groundwater quality of three different land uses, (1) exotic pine plantation ready for harvest (Waimarino River Catchment), (2) an urban area characterised by a land treatment facility for sewage effluent from Turangi (Turangi oxidation ponds), and (3) a natural wetland (South Taupo Wetlands) demonstrates that groundwater quality in the southern region of the Lake Taupo catchment is controlled by both natural and human influences in the area. Comparative water quality issues can be summarised as follows. (1) Naturally high concentrations of reduced iron and manganese are present in all three study areas, with the highest concentrations found in the natural wetland area and around the Turangi land treatment facility. (2) Concentrations of sodium, chloride, potassium, and ammonium in the groundwater down-gradient of the Turangi oxidation ponds are elevated relative to the other two study areas. Stable isotopic signatures also show that the groundwater has been influenced by surface water from the oxidation ponds, mostly due to additional evaporation caused by the relatively long residence time of the water (125 days) in the oxidation ponds. Elevated concentrations of ammonium also occur in deep groundwater under the forest areas of the Waimarino River catchment. (3) The water at all three sites is generally unsuitable for drinking supplies due to naturally elevated concentrations of reduced iron and manganese in the groundwater and elevated concentrations of ammonium at many monitoring sites, particularly around the Turangi land treatment site and the Waimarino deep aquifer monitoring sites. Aeration followed by settling or filtration of the groundwater could significantly reduce the concentrations of iron and manganese. (4) Elevated concentrations of reduced iron and manganese are unlikely to affect the water quality of Lake Taupo as all reduced iron and manganese will be oxidised once the water reaches the lake and precipitate as oxyhydroxide minerals

  7. An integrative study of a meromictic lake ecosystem in Antarctica.

    Science.gov (United States)

    Lauro, Federico M; DeMaere, Matthew Z; Yau, Sheree; Brown, Mark V; Ng, Charmaine; Wilkins, David; Raftery, Mark J; Gibson, John A E; Andrews-Pfannkoch, Cynthia; Lewis, Matthew; Hoffman, Jeffrey M; Thomas, Torsten; Cavicchioli, Ricardo

    2011-05-01

    In nature, the complexity and structure of microbial communities varies widely, ranging from a few species to thousands of species, and from highly structured to highly unstructured communities. Here, we describe the identity and functional capacity of microbial populations within distinct layers of a pristine, marine-derived, meromictic (stratified) lake (Ace Lake) in Antarctica. Nine million open reading frames were analyzed, representing microbial samples taken from six depths of the lake size fractionated on sequential 3.0, 0.8 and 0.1 μm filters, and including metaproteome data from matching 0.1 μm filters. We determine how the interactions of members of this highly structured and moderately complex community define the biogeochemical fluxes throughout the entire lake. Our view is that the health of this delicate ecosystem is dictated by the effects of the polar light cycle on the dominant role of green sulfur bacteria in primary production and nutrient cycling, and the influence of viruses/phage and phage resistance on the cooperation between members of the microbial community right throughout the lake. To test our assertions, and develop a framework applicable to other microbially driven ecosystems, we developed a mathematical model that describes how cooperation within a microbial system is impacted by periodic fluctuations in environmental parameters on key populations of microorganisms. Our study reveals a mutualistic structure within the microbial community throughout the lake that has arisen as the result of mechanistic interactions between the physico-chemical parameters and the selection of individual members of the community. By exhaustively describing and modelling interactions in Ace Lake, we have developed an approach that may be applicable to learning how environmental perturbations affect the microbial dynamics in more complex aquatic systems.

  8. Voltammetric studies of copper speciation in Lake Elementaita

    International Nuclear Information System (INIS)

    Gikandi, J.T.; Thairu, H.M.; Schroder, K.

    1995-01-01

    Differential pulse polarography (DPP) and diffential pulse anodic stripping voltammetry (DPASV) have been used to study the complex formation between copper and chloride, fluoride , bicarbonate, carbonate and hydroxide ligands in both potassium nitrate and lake water media. The lake water was sampled from Lake Elementaita (Kenya). It was found that copper( II) ions formed copper (1) complexes with the above ligands due to step-wise reduction of copper(11) to copper (1) ions on the mercury electrode. Fluoride and bicarbonate ligands formed complexes of the type CuL and CuL2 (where L is a monodentate ligand) while the chlride formed only CuL complex. The hydroxide and the carbonate ligands formed a third complex, CuL3, in addition to CuL2, and CuL complexes. From the graphs of species distribution, the values of stability constants and the levels of the ligands in the lake, it was found that the chloride and the carbonate ligands contributed most of the speciation of the copper in the Lake Elementaita, while the hydroxide ligand contributed least. (author)

  9. Estimation of mercury emissions from forest fires, lakes, regional and local sources using measurements in Milwaukee and an inverse method

    Directory of Open Access Journals (Sweden)

    B. de Foy

    2012-10-01

    Full Text Available Gaseous elemental mercury is a global pollutant that can lead to serious health concerns via deposition to the biosphere and bio-accumulation in the food chain. Hourly measurements between June 2004 and May 2005 in an urban site (Milwaukee, WI show elevated levels of mercury in the atmosphere with numerous short-lived peaks as well as longer-lived episodes. The measurements are analyzed with an inverse model to obtain information about mercury emissions. The model is based on high resolution meteorological simulations (WRF, hourly back-trajectories (WRF-FLEXPART and a chemical transport model (CAMx. The hybrid formulation combining back-trajectories and Eulerian simulations is used to identify potential source regions as well as the impacts of forest fires and lake surface emissions. Uncertainty bounds are estimated using a bootstrap method on the inversions. Comparison with the US Environmental Protection Agency's National Emission Inventory (NEI and Toxic Release Inventory (TRI shows that emissions from coal-fired power plants are properly characterized, but emissions from local urban sources, waste incineration and metal processing could be significantly under-estimated. Emissions from the lake surface and from forest fires were found to have significant impacts on mercury levels in Milwaukee, and to be underestimated by a factor of two or more.

  10. Estimation of mercury emissions from forest fires, lakes, regional and local sources using measurements in Milwaukee and an inverse method

    Science.gov (United States)

    de Foy, B.; Wiedinmyer, C.; Schauer, J. J.

    2012-10-01

    Gaseous elemental mercury is a global pollutant that can lead to serious health concerns via deposition to the biosphere and bio-accumulation in the food chain. Hourly measurements between June 2004 and May 2005 in an urban site (Milwaukee, WI) show elevated levels of mercury in the atmosphere with numerous short-lived peaks as well as longer-lived episodes. The measurements are analyzed with an inverse model to obtain information about mercury emissions. The model is based on high resolution meteorological simulations (WRF), hourly back-trajectories (WRF-FLEXPART) and a chemical transport model (CAMx). The hybrid formulation combining back-trajectories and Eulerian simulations is used to identify potential source regions as well as the impacts of forest fires and lake surface emissions. Uncertainty bounds are estimated using a bootstrap method on the inversions. Comparison with the US Environmental Protection Agency's National Emission Inventory (NEI) and Toxic Release Inventory (TRI) shows that emissions from coal-fired power plants are properly characterized, but emissions from local urban sources, waste incineration and metal processing could be significantly under-estimated. Emissions from the lake surface and from forest fires were found to have significant impacts on mercury levels in Milwaukee, and to be underestimated by a factor of two or more.

  11. A preliminary magnetic study of Sawa lake sediments, Southern Iraq

    Science.gov (United States)

    Ameen, Nawrass

    2016-04-01

    A preliminary magnetic study combined with chemical analyses was carried out in Sawa Lake in Al-Muthanna province, southern Iraq, about 22 km south west of Samawa city (31°18'48.80"N, 45°0'25.25"E). The lake is about 4.74 km length, 1.75 km width and 5.5 m height, it is surrounded by a salt rim which is higher than the lake water by about 2.8 m and sea water by about 18.5 m (Naqash et al., 1977 in Hassan, 2007). The lake is an elongated closed basin with no surface water available to it, it may be fed by groundwater of the Euphrates and Dammam aquifers through system of joints and cracks. This study aims to investigate the concentrations of selected heavy metals as pollutants and magnetic susceptibility (MS) and other magnetic properties of sediment samples from fifty sites collected from the bottom of the lake, the study area lies in an industrial area. The results show spatial variations of MS with mean value of about 4.58 x 10-8 m3 kg-1. Scanning electron microscopy and magnetic mineralogy parameters indicate the dominance of soft magnetic phase like magnetite and presence of hard magnetic phase like hematite. Spatial variations of MS combined with the concentrations of heavy metals suggests the efficiency of magnetic methods as effective, inexpensive and non-time consuming method to outlining the heavy metal pollution. References: Hassan W.F., 2007. The Physio-chemical characteristic of Sawa lake water in Samawa city-Iraq. Marine Mesopotamica, 22(2), 167-179.

  12. Forest structure in low diversity tropical forests: a study of Hawaiian wet and dry forests

    Science.gov (United States)

    R. Ostertag; F. Inman-Narahari; S. Cordell; C.P. Giardina; L. Sack

    2014-01-01

    The potential influence of diversity on ecosystem structure and function remains a topic of significant debate, especially for tropical forests where diversity can range widely. We used Center for Tropical Forest Science (CTFS) methodology to establish forest dynamics plots in montane wet forest and lowland dry forest on Hawai‘i Island. We compared the species...

  13. Restoration of Eutrophic Lakes with Fluctuating Water Levels: A 20-Year Monitoring Study of Two Inter-Connected Lakes

    Directory of Open Access Journals (Sweden)

    Meryem Beklioğlu

    2017-02-01

    Full Text Available Eutrophication continues to be the most important problem preventing a favorable environmental state and detrimentally impacting the ecosystem services of lakes. The current study describes the results of analyses of 20 year monitoring data from two interconnected Anatolian lakes, Lakes Mogan and Eymir, receiving sewage effluents and undergoing restoration. The first step of restoration in both lakes was sewage effluent diversion. Additionally, in hypertrophic Lake Eymir, biomanipulation was conducted, involving removal of benthi-planktivorous fish and prohibition of pike fishing. The monitoring period included high (H and low (L water levels (WL enabling elucidation of the effects of hydrological changes on lake restoration. In shallower Lake Mogan, macrophyte abundance increased after the sewage effluent diversion in periods with low water levels even at turbid water. In comparatively deeper Lake Eymir, the first biomanipulation led to a clear water state with abundant macrophyte coverage. However, shortly after biomanipulation, the water clarity declined, coinciding with low water level (LWL periods during which nutrient concentrations increased. A second biomanipulation was conducted, mostly during high water level (HWL period, resulting in a major decrease in nutrient concentrations and clearer water, but without an expansion of macrophytes. We conclude that repetitive fish removal may induce recovery but its success may be confounded by high availability of nutrients and adverse hydrological conditions.

  14. Freshwater lakes--a potential source for aquaculture activities--a model study on Perumal Lake, Cuddalore, Tamil Nadu.

    Science.gov (United States)

    Usha, R; Ramalingam, K; Bharathi Rajan, U D

    2006-10-01

    The freshwater Perumal lake located at Cuddalore was assessed for its suitability and potential for aquaculture practices. Various hydrobiological parameters determined reveals that the various physicochemical characteristics are with in normal range of values. The DO level, BOD and COD values determined in the lake revealed the consequences of community activities and pollution possibilities. The primary productivity data revealed maximum productivity during March which infer that the lake is unaffected by anthropogenic disturbance and community contamination. The bacterial count remained higher during the monsoon periods, which characterize profuse rainfall and storm water discharge into the lake. The microfauna includes zooplankter such as cladocerans, copepods, rotifers and ostracods. Benthos include carps, catfishes, mullets and prawns. The above study revealed that the various parameters in the lake conform to the levels suited for freshwater fish culture and represents a resource for scientific management.

  15. Quantifying understorey vegetation in the US Lake States: a proposed framework to inform regional forest carbon stocks

    Science.gov (United States)

    Matthew B. Russell; Anthony W. D' Amato; Bethany K. Schulz; Christopher W. Woodall; Grant M. Domke; John B. Bradford

    2014-01-01

    The contribution of understorey vegetation (UVEG) to forest ecosystem biomass and carbon (C) across diverse forest types has, to date, eluded quantification at regional and national scales. Efforts to quantify UVEG C have been limited to field-intensive studies or broad-scalemodelling approaches lacking fieldmeasurements. Although large-scale inventories of UVEG C are...

  16. Ten-year results from the long-term soil productivity study in aspen ecosystems of the northern Great Lakes region

    Science.gov (United States)

    Richard Voldseth; Brian J. Palik; John Elioff

    2011-01-01

    Impacts of organic matter removal and compaction on soil properties and productivity are reported from the first 10 years of the Long-Term Soil Productivity Study in Great Lakes aspen ecosystems. Organic matter removal treatments included main bole, total tree harvest, and total tree harvest with forest floor removal. Compaction treatments included minimal compaction,...

  17. Urban lake system eutrophication – A case study | MAMA | Journal ...

    African Journals Online (AJOL)

    The dynamic eutrophication process study of Yamoussoukro lake system in Côte d'Ivoire was carried out from February 1997 to January 1998. It appeared that this phenomenon is related to the nutriments that are phosphorus mainly and nitrogen. It was shown that the fluctuations of these nutriments depend on the climatic ...

  18. Lake and bulk sampling chemistry, NADP, and IMPROVE air quality data analysis on the Bridger-Teton National Forest (USFS Region 4)

    Science.gov (United States)

    Jill Grenon; Terry Svalberg; Ted Porwoll; Mark Story

    2010-01-01

    Air quality monitoring data from several programs in and around the Bridger-Teton (B-T) National Forest - National Atmospheric Deposition Program (NADP), longterm lake monitoring, long-term bulk precipitation monitoring (both snow and rain), and Interagency Monitoring of Protected Visual Environments (IMPROVE) - were analyzed in this report. Trends were analyzed using...

  19. Using traditional ecological knowledge as a basis for targeted forest inventory: paper birch (Betula papyrifera) in the US Great Lakes Region

    Science.gov (United States)

    Marla R. Emery; Alexandra Wrobel; Mark H. Hansen; Michael Dockry; W. Keith Moser; Kekek Jason Stark; Jonathan H. Gilbert

    2014-01-01

    Traditional ecological knowledge (TEK) has been proposed as a basis for enhanced understanding of ecological systems and their management. TEK also can contribute to targeted inventories of resources not included in standard mensuration. We discuss the results of a cooperative effort between the Great Lakes Indian Fish and Wildlife Commission (GLIFWC) and USDA Forest...

  20. Forest structure in low-diversity tropical forests: a study of Hawaiian wet and dry forests.

    Science.gov (United States)

    Ostertag, Rebecca; Inman-Narahari, Faith; Cordell, Susan; Giardina, Christian P; Sack, Lawren

    2014-01-01

    The potential influence of diversity on ecosystem structure and function remains a topic of significant debate, especially for tropical forests where diversity can range widely. We used Center for Tropical Forest Science (CTFS) methodology to establish forest dynamics plots in montane wet forest and lowland dry forest on Hawai'i Island. We compared the species diversity, tree density, basal area, biomass, and size class distributions between the two forest types. We then examined these variables across tropical forests within the CTFS network. Consistent with other island forests, the Hawai'i forests were characterized by low species richness and very high relative dominance. The two Hawai'i forests were floristically distinct, yet similar in species richness (15 vs. 21 species) and stem density (3078 vs. 3486/ha). While these forests were selected for their low invasive species cover relative to surrounding forests, both forests averaged 5->50% invasive species cover; ongoing removal will be necessary to reduce or prevent competitive impacts, especially from woody species. The montane wet forest had much larger trees, resulting in eightfold higher basal area and above-ground biomass. Across the CTFS network, the Hawaiian montane wet forest was similar to other tropical forests with respect to diameter distributions, density, and aboveground biomass, while the Hawai'i lowland dry forest was similar in density to tropical forests with much higher diversity. These findings suggest that forest structural variables can be similar across tropical forests independently of species richness. The inclusion of low-diversity Pacific Island forests in the CTFS network provides an ∼80-fold range in species richness (15-1182 species), six-fold variation in mean annual rainfall (835-5272 mm yr(-1)) and 1.8-fold variation in mean annual temperature (16.0-28.4°C). Thus, the Hawaiian forest plots expand the global forest plot network to enable testing of ecological theory for

  1. Value Assessment of Artificial Wetland Derived from Mining Subsided Lake: A Case Study of Jiuli Lake Wetland in Xuzhou

    Directory of Open Access Journals (Sweden)

    Laijian Wang

    2017-10-01

    Full Text Available Mining subsided lakes are major obstacles for ecological restoration and resource reuse in mining regions. Transforming mining subsided lakes into artificial wetlands is an ecological restoration approach that has been attempted in China in recent years, but a value assessment of the approach still needs systematic research. This paper considers Jiuli Lake wetland, an artificial wetland derived from restoration of a mining subsided lake in plain area, as a case study. A value assessment model for the artificial wetland was established based on cost–benefit analysis by means of field monitoring, social surveys, GIS geostatistics, raster calculation methods, etc. Empirical analysis and calculations were performed on the case study region. The following conclusions were drawn: (1 after ecological restoration, ecosystem services of Jiuli Lake wetland which has become a national level wetland park yield positive values; (2 the improved environment of the Jiuli Lake wetland has a spillover effect on the price of surrounding land, resulting in land price appreciation; (3 using GIS geostatistics and raster calculation methods, the impact range, strength, and value of the spillover effect can be explicitly measured; (4 through the establishment of a value assessment model of the artificial wetland, incomes of the ecological restoration was found to be sufficient to cover the implementation costs, which provides a research foundation for economic feasibility of ecological restoration of mining subsided lakes.

  2. 75 FR 32738 - Gallatin National Forest-Hebgen Lake Ranger District; MT; Lonesome Wood Vegetation Management...

    Science.gov (United States)

    2010-06-09

    ...; Lonesome Wood Vegetation Management Project 2 AGENCY: Forest Service, USDA. ACTION: Notice of Intent to prepare an Environmental Impact Statement. SUMMARY: This integrated forest vegetation management project is designed to achieve the goals of increased firefighter and public safety, reduced wildland fire...

  3. Homogenization of northern U.S. Great Lakes forests due to land use

    Science.gov (United States)

    Lisa A. Schulte; David J. Mladenoff; Thomas R. Crow; Laura C. Merrick; David T. Cleland

    2007-01-01

    Human land use of forested regions has intensified worldwide in recent decades, threatening long-term sustainability. Primary effects include conversion of land cover or reversion to an earlier stage of successional development. Both types of change can have cascading effects through ecosystems; however, the longterm effects where forests are allowed to regrow are...

  4. 75 FR 82141 - Stakeholder Meetings Regarding the U.S.-Flag Great Lakes Fleet Revitalization Study

    Science.gov (United States)

    2010-12-29

    ... Meetings Regarding the U.S.-Flag Great Lakes Fleet Revitalization Study AGENCY: Maritime Administration... Administration's U.S.-Flag Great Lakes Fleet Revitalization Study. The three meetings will be identical in terms... participation. The U.S.-Flag Great Lakes Fleet Revitalization Study will examine the current and potential...

  5. An Overview of Hydrologic Studies at Center for Forested Wetlands Research, USDA Forest Service

    Science.gov (United States)

    Devendra M. Amatya; Carl C. Trettin; R. Wayne Skaggs; Timothy J. Callahan; Ge Sun; Masato Miwa; John E. Parsons

    2004-01-01

    Managing forested wetland landscapes for water quality improvement and productivity requires a detailed understanding of functional linkages between ecohydrological processes and management practices. Studies are being conducted at Center for Forested Wetlands Research (CFWR), USDA Forest Service to understand the fundamental hydrologic and biogeochemical processes...

  6. Eutrophication potential of Payette Lake, Idaho

    Science.gov (United States)

    Woods, Paul F.

    1997-01-01

    Payette Lake was studied during water years 1995-96 to determine the 20.5-square-kilometer lake's assimilative capacity for nutrients and, thus, its eutrophication potential. The study included quantification of hydrologic and nutrient budgets, characterization of water quality in the limnetic and littoral zones, development of an empirical nutrient load/lake response model, and estimation of the limnological effects of a large-scale forest fire in the lake's 373-square-kilometer watershed during the autumn of 1994. Streamflow from the North Fork Payette River, the lake's primary tributary, delivered about 73 percent of the lake's inflow over the 2 years. Outflow from the lake, measured since 1908, was 128 and 148 percent of the long-term average in 1995 and 1996, respectively. The larger volumes of outflow reduced the long-term average water-

  7. Mercury methylation in Sphagnum moss mats and its association with sulfate-reducing bacteria in an acidic Adirondack forest lake wetland.

    Science.gov (United States)

    Yu, Ri-Qing; Adatto, Isaac; Montesdeoca, Mario R; Driscoll, Charles T; Hines, Mark E; Barkay, Tamar

    2010-12-01

    Processes leading to the bioaccumulation of methylmercury (MeHg) in northern wetlands are largely unknown. We have studied various ecological niches within a remote, acidic forested lake ecosystem in the southwestern Adirondacks, NY, to discover that mats comprised of Sphagnum moss were a hot spot for mercury (Hg) and MeHg accumulation (190.5 and 18.6 ng g⁻¹ dw, respectively). Furthermore, significantly higher potential methylation rates were measured in Sphagnum mats as compared with other sites within Sunday Lake's ecosystem. Although MPN estimates showed a low biomass of sulfate-reducing bacteria (SRB), 2.8 × 10⁴ cells mL⁻¹ in mat samples, evidence consisting of (1) a twofold stimulation of potential methylation by the addition of sulfate, (2) a significant decrease in Hg methylation in the presence of the sulfate reduction inhibitor molybdate, and (3) presence of dsrAB-like genes in mat DNA extracts, suggested that SRB were involved in Hg methylation. Sequencing of dsrB genes indicated that novel SRB, incomplete oxidizers including Desulfobulbus spp. and Desulfovibrio spp., and syntrophs dominated the sulfate-reducing guild in the Sphagnum moss mat. Sphagnum, a bryophyte dominating boreal peatlands, and its associated microbial communities appear to play an important role in the production and accumulation of MeHg in high-latitude ecosystems. © 2010 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  8. Forests

    Science.gov (United States)

    Louis R. Iverson; Mark W. Schwartz

    1994-01-01

    Originally diminished by development, forests are coming back: forest biomass is accumulating. Forests are repositories for many threatened species. Even with increased standing timber, however, biodiversity is threatened by increased forest fragmentation and by exotic species.

  9. Coelastrum pascheri sp. n., a new green alga from lakes of the Bohemian Forest

    Czech Academy of Sciences Publication Activity Database

    Lukavský, Jaromír

    2006-01-01

    Roč. 61, Suppl20 (2006), S485-S490 ISSN 0006-3088 R&D Projects: GA MŠk 1M0571 Institutional research plan: CEZ:AV0Z60050516 Keywords : Coelastrum pascheri, sp. n * algae * lakes Subject RIV: EF - Botanics Impact factor: 0.213, year: 2006

  10. Organic matter fuel briquettes as a forest conservation tool in Lake ...

    African Journals Online (AJOL)

    Environmental degradation including deforestation is of great concern in the whole of sub-Saharan Africa, even in many protected areas. One of them is Lake Malawi National Park (LMNP), which encases the most populated village in Malawi, Chembe. The rise in population has increased the pressure to utilize natural ...

  11. Organic matter degradation in Lake Baikal - a sediment trap study

    DEFF Research Database (Denmark)

    Schubert, Carsten J.; Niggemann, Jutta; Lomstein, Bente Aagaard

    Lake Baikal offers a unique opportunity to study water column processes in a freshwater system with conditions similar to oceanic systems, e. g. great water depth and oxygenated water column. Investigations on sediment trap material provide information on the early stages of organic matter...... degradation in the water column. Sediment trap material from 18 different water depths has been analysed for bulk organic matter parameters, including organic carbon and nitrogen isotopic compositions, chlorin concentrations, and Chlorin Indices [1]. Detailed studies focused on the concentration...... and composition of amino acids and fatty acids. The extent of organic matter degradation in the water column of Lake Baikal is reflected in the fluxes of total organic carbon, chlorins, amino acids, and fatty acids at different water depths. In line with earlier studies in marine systems, the labile compounds...

  12. BATHYMETRIC STUDY OF WADI EL-RAYAN LAKES, EGYPT

    Directory of Open Access Journals (Sweden)

    Radwan Gad Elrab ABD ELLAH

    2016-12-01

    Full Text Available Bathymetry is a technique of measuring depths to determine the morphometry of water bodies. The derivation of bathymetry from the surveys is one of the basic researches of the aquatic environment, which has several practical implications to on the lake environment and it's monitoring. Wadi El-Rayan, as Ramsar site, is a very important wetland, in Egypt, as a reservoir for agricultural drainage water, fisheries and tourism. The Lakes are man-made basins in the Fayoum depression. Wadi El-Rayan Lakes are two reservoirs (upper Lake and Lower Lake, at different elevations. The Upper Lake is classified as open basin, while the Lower Lake is a closed basin, with no significant obvious water outflow. During recent decades, human impact on Wadi El-Rayan Lakes has increased due to intensification of agriculture and fish farming. Analyses of bathyemtric plans from 1996, 2010 and 2016 showed, the differences between morphometric parameters of the Upper Lake were generally small, while the Lower Lake changes are obvious at the three periods. The small fluctuate, in the features of Upper Lake is due to the water balance between the water inflow and water. The Lower Lake has faced extreme water loss through last twenty years is due to the agricultural lands and fish farms extended in the depression. The Upper Lake is rich in Lakeshores macrophyets, while decline the water plants in the Lower Lake. With low water levels, in the Lower Lake, the future continuity of the Lake system is in jeopardy

  13. Measuring the Quality of the Lakeside Tourist Destinations: Case Study of Lake Palić and Lake Srebrno (Serbia)

    OpenAIRE

    Jelica J. MARKOVIĆ; Dragoslav J. PAVIĆ; Minucsér M. MÉSZAROS; Marko D. PETROVIĆ

    2015-01-01

    The purpose of this study is to determine the dimensions of the lakeside tourist destinations quality through the cases of Lake Palić and Lake Srebrno (Serbia), by interviewing daily visitors and tourists and to determine which dimensions of quality have a crucial impact on the overall satisfaction of daily visitors and tourists. Various models have been developed to measure quality. In this paper, the quality is measured by the model that is appropriate for lakeside tourist destinations, dev...

  14. 76 FR 41753 - Sierra National Forest, Bass Lake Ranger District, California, Grey's Mountain Ecosystem...

    Science.gov (United States)

    2011-07-15

    ..., California, Grey's Mountain Ecosystem Restoration Project AGENCY: Forest Service, USDA. ACTION: Notice of...: Background Information: The Grey's Mountain Ecosystem Restoration Project (Madera County, California) lies... vegetation. Currently, vegetation within the Grey's Mountain Ecosystem Restoration Project has changed from...

  15. Long-term ecological research of glacial lakes in the Bohemian Forest and their catchments

    Czech Academy of Sciences Publication Activity Database

    Vrba, Jaroslav; Kopáček, Jiří; Tahovská, K.; Šantrůčková, H.

    2015-01-01

    Roč. 21, č. 1 (2015), s. 53-71 ISSN 1211-7420 Institutional support: RVO:60077344 Keywords : atmospheric acidification * biological recovery * nutrients * soil * water * forest dieback Subject RIV: EH - Ecology, Behaviour

  16. The structuring role of fish in Greenland lakes: an overview based on contemporary and paleoecological studies of 87 lakes from the low and the high Arctic

    DEFF Research Database (Denmark)

    Jeppesen, Erik; Lauridsen, Torben L.; Christoffersen, Kirsten S.

    2017-01-01

    Lakes in Greenland are species-poor ecosystems and many are fishless. We studied the structuring role of fish in lakes in high- and low-Arctic Greenland. Major differences were observed in the trophic structure of the 87 lakes studied. Pelagic zooplankton biomass was on average 3-4-fold higher in...

  17. Hydrogeological and geochemical studies in the Perch Lake basin

    International Nuclear Information System (INIS)

    Barry, P.J.

    1979-08-01

    The Perch Lake basin is a small drainage system along the Ottawa River about 200 km west of Ottawa on the Canadian Shield. Since 1975, groups of scientists from several Canadian universities and government departments have been studying the hydrological, geological and geochemical properties of the basin. The object of these studies is to develop and test simulation models used to describe the time-dependent mass flow rates of water and dissolved and suspended substances through the basin. To review progress, a symposium/workshop was held at Chalk Rier in 1978 April. This report contains 24 extended summaries of the material presented verbally at the workshop. Subject matters include atmospheric sources and sinks, mass flows through the surface and subsurface regimes in the drainage basins and interactions occurring in the lake. (author)

  18. Identifying Watershed Regions Sensitive to Soil Erosion and Contributing to Lake Eutrophication--A Case Study in the Taihu Lake Basin (China).

    Science.gov (United States)

    Lin, Chen; Ma, Ronghua; He, Bin

    2015-12-24

    Taihu Lake in China is suffering from severe eutrophication partly due to non-point pollution from the watershed. There is an increasing need to identify the regions within the watershed that most contribute to lake water degradation. The selection of appropriate temporal scales and lake indicators is important to identify sensitive watershed regions. This study selected three eutrophic lake areas, including Meiliang Bay (ML), Zhushan Bay (ZS), and the Western Coastal region (WC), as well as multiple buffer zones next to the lake boundary as the study sites. Soil erosion intensity was designated as a watershed indicator, and the lake algae area was designated as a lake quality indicator. The sensitive watershed region was identified based on the relationship between these two indicators among different lake divisions for a temporal sequence from 2000 to 2012. The results show that the relationship between soil erosion modulus and lake quality varied among different lake areas. Soil erosion from the two bay areas was more closely correlated with water quality than soil erosion from the WC region. This was most apparent at distances of 5 km to 10 km from the lake, where the r² was as high as 0.764. Results indicate that soil erosion could be used as an indicator for identifying key watershed protection areas. Different lake areas need to be considered separately due to differences in geographical features, land use, and the corresponding effects on lake water quality.

  19. Identifying Watershed Regions Sensitive to Soil Erosion and Contributing to Lake Eutrophication—A Case Study in the Taihu Lake Basin (China)

    Science.gov (United States)

    Lin, Chen; Ma, Ronghua; He, Bin

    2015-01-01

    Taihu Lake in China is suffering from severe eutrophication partly due to non-point pollution from the watershed. There is an increasing need to identify the regions within the watershed that most contribute to lake water degradation. The selection of appropriate temporal scales and lake indicators is important to identify sensitive watershed regions. This study selected three eutrophic lake areas, including Meiliang Bay (ML), Zhushan Bay (ZS), and the Western Coastal region (WC), as well as multiple buffer zones next to the lake boundary as the study sites. Soil erosion intensity was designated as a watershed indicator, and the lake algae area was designated as a lake quality indicator. The sensitive watershed region was identified based on the relationship between these two indicators among different lake divisions for a temporal sequence from 2000 to 2012. The results show that the relationship between soil erosion modulus and lake quality varied among different lake areas. Soil erosion from the two bay areas was more closely correlated with water quality than soil erosion from the WC region. This was most apparent at distances of 5 km to 10 km from the lake, where the r2 was as high as 0.764. Results indicate that soil erosion could be used as an indicator for identifying key watershed protection areas. Different lake areas need to be considered separately due to differences in geographical features, land use, and the corresponding effects on lake water quality. PMID:26712772

  20. Forest Structure in Low-Diversity Tropical Forests: A Study of Hawaiian Wet and Dry Forests

    Science.gov (United States)

    Ostertag, Rebecca; Inman-Narahari, Faith; Cordell, Susan; Giardina, Christian P.; Sack, Lawren

    2014-01-01

    The potential influence of diversity on ecosystem structure and function remains a topic of significant debate, especially for tropical forests where diversity can range widely. We used Center for Tropical Forest Science (CTFS) methodology to establish forest dynamics plots in montane wet forest and lowland dry forest on Hawai‘i Island. We compared the species diversity, tree density, basal area, biomass, and size class distributions between the two forest types. We then examined these variables across tropical forests within the CTFS network. Consistent with other island forests, the Hawai‘i forests were characterized by low species richness and very high relative dominance. The two Hawai‘i forests were floristically distinct, yet similar in species richness (15 vs. 21 species) and stem density (3078 vs. 3486/ha). While these forests were selected for their low invasive species cover relative to surrounding forests, both forests averaged 5–>50% invasive species cover; ongoing removal will be necessary to reduce or prevent competitive impacts, especially from woody species. The montane wet forest had much larger trees, resulting in eightfold higher basal area and above-ground biomass. Across the CTFS network, the Hawaiian montane wet forest was similar to other tropical forests with respect to diameter distributions, density, and aboveground biomass, while the Hawai‘i lowland dry forest was similar in density to tropical forests with much higher diversity. These findings suggest that forest structural variables can be similar across tropical forests independently of species richness. The inclusion of low-diversity Pacific Island forests in the CTFS network provides an ∼80-fold range in species richness (15–1182 species), six-fold variation in mean annual rainfall (835–5272 mm yr−1) and 1.8-fold variation in mean annual temperature (16.0–28.4°C). Thus, the Hawaiian forest plots expand the global forest plot network to enable testing of

  1. Forest structure in low-diversity tropical forests: a study of Hawaiian wet and dry forests.

    Directory of Open Access Journals (Sweden)

    Rebecca Ostertag

    Full Text Available The potential influence of diversity on ecosystem structure and function remains a topic of significant debate, especially for tropical forests where diversity can range widely. We used Center for Tropical Forest Science (CTFS methodology to establish forest dynamics plots in montane wet forest and lowland dry forest on Hawai'i Island. We compared the species diversity, tree density, basal area, biomass, and size class distributions between the two forest types. We then examined these variables across tropical forests within the CTFS network. Consistent with other island forests, the Hawai'i forests were characterized by low species richness and very high relative dominance. The two Hawai'i forests were floristically distinct, yet similar in species richness (15 vs. 21 species and stem density (3078 vs. 3486/ha. While these forests were selected for their low invasive species cover relative to surrounding forests, both forests averaged 5->50% invasive species cover; ongoing removal will be necessary to reduce or prevent competitive impacts, especially from woody species. The montane wet forest had much larger trees, resulting in eightfold higher basal area and above-ground biomass. Across the CTFS network, the Hawaiian montane wet forest was similar to other tropical forests with respect to diameter distributions, density, and aboveground biomass, while the Hawai'i lowland dry forest was similar in density to tropical forests with much higher diversity. These findings suggest that forest structural variables can be similar across tropical forests independently of species richness. The inclusion of low-diversity Pacific Island forests in the CTFS network provides an ∼80-fold range in species richness (15-1182 species, six-fold variation in mean annual rainfall (835-5272 mm yr(-1 and 1.8-fold variation in mean annual temperature (16.0-28.4°C. Thus, the Hawaiian forest plots expand the global forest plot network to enable testing of ecological

  2. Aerial thermography studies of power plant heated lakes

    Energy Technology Data Exchange (ETDEWEB)

    Villa-Aleman, E.

    2000-01-26

    Remote sensing temperature measurements of water bodies is complicated by the temperature differences between the true surface or skin water and the bulk water below. Weather conditions control the reduction of the skin temperature relative to the bulk water temperature. Typical skin temperature depressions range from a few tenths of a degree Celsius to more than one degree. In this research project, the Savannah River Technology Center (SRTC) used aerial thermography and surface-based meteorological and water temperature measurements to study a power plant cooling lake in South Carolina. Skin and bulk water temperatures were measured simultaneously for imagery calibration and to produce a database for modeling of skin temperature depressions as a function of weather and bulk water temperatures. This paper will present imagery that illustrates how the skin temperature depression was affected by different conditions in several locations on the lake and will present skin temperature modeling results.

  3. Application of an imputation method for geospatial inventory of forest structural attributes across multiple spatial scales in the Lake States, U.S.A

    Science.gov (United States)

    Deo, Ram K.

    Credible spatial information characterizing the structure and site quality of forests is critical to sustainable forest management and planning, especially given the increasing demands and threats to forest products and services. Forest managers and planners are required to evaluate forest conditions over a broad range of scales, contingent on operational or reporting requirements. Traditionally, forest inventory estimates are generated via a design-based approach that involves generalizing sample plot measurements to characterize an unknown population across a larger area of interest. However, field plot measurements are costly and as a consequence spatial coverage is limited. Remote sensing technologies have shown remarkable success in augmenting limited sample plot data to generate stand- and landscape-level spatial predictions of forest inventory attributes. Further enhancement of forest inventory approaches that couple field measurements with cutting edge remotely sensed and geospatial datasets are essential to sustainable forest management. We evaluated a novel Random Forest based k Nearest Neighbors (RF-kNN) imputation approach to couple remote sensing and geospatial data with field inventory collected by different sampling methods to generate forest inventory information across large spatial extents. The forest inventory data collected by the FIA program of US Forest Service was integrated with optical remote sensing and other geospatial datasets to produce biomass distribution maps for a part of the Lake States and species-specific site index maps for the entire Lake State. Targeting small-area application of the state-of-art remote sensing, LiDAR (light detection and ranging) data was integrated with the field data collected by an inexpensive method, called variable plot sampling, in the Ford Forest of Michigan Tech to derive standing volume map in a cost-effective way. The outputs of the RF-kNN imputation were compared with independent validation

  4. Stakeholders’ perception of forest management: a Portuguese mountain case study

    Energy Technology Data Exchange (ETDEWEB)

    Marta-Costa, A.; Torres-Manso, F.; Pinto, R.; Tibério, L.; Carneiro, I.

    2016-07-01

    Aim of study: The Natura 2000 Network “Montemuro Mountain” Site in Portugal. Material and methods: This study combined several consultation and citizen participation techniques. Main results: The perceptions shared by the stakeholders are some similar, others not similar and others still quite paradoxical regarding forest characteristics and the opportunities they offer. The study has shown that it is possible to implement and improve citizen participation methodologies. This can be a viable way towards more effective forest management and fire prevention as this may help blunt conflicts of interest in forest space management. However, for participation to be truly effective and representative, a policy regarding training and awareness of the importance of information is necessary. Research highlights: The stakeholder perceptions on forests and forest management are assessed; forest fires and agrarian abandonment are central for territory’s development; depopulation, old age and absenteeism emphasize degradation of forest areas; Conscious citizen participation benefit policymaking and forest management. (Author)

  5. Stakeholders’ perception of forest management: a Portuguese mountain case study

    International Nuclear Information System (INIS)

    Marta-Costa, A.; Torres-Manso, F.; Pinto, R.; Tibério, L.; Carneiro, I.

    2016-01-01

    Aim of study: The Natura 2000 Network “Montemuro Mountain” Site in Portugal. Material and methods: This study combined several consultation and citizen participation techniques. Main results: The perceptions shared by the stakeholders are some similar, others not similar and others still quite paradoxical regarding forest characteristics and the opportunities they offer. The study has shown that it is possible to implement and improve citizen participation methodologies. This can be a viable way towards more effective forest management and fire prevention as this may help blunt conflicts of interest in forest space management. However, for participation to be truly effective and representative, a policy regarding training and awareness of the importance of information is necessary. Research highlights: The stakeholder perceptions on forests and forest management are assessed; forest fires and agrarian abandonment are central for territory’s development; depopulation, old age and absenteeism emphasize degradation of forest areas; Conscious citizen participation benefit policymaking and forest management. (Author)

  6. Disturbance severity and net primary production resilience of a Great Lakes forest ecosystem

    Science.gov (United States)

    Goodrich-Stuart, E. J.; Fahey, R.; De La Cruz, A.; Gough, C. M.

    2013-12-01

    As many Eastern deciduous forests of North America transition from early to mid-succession, the future of regional terrestrial carbon (C) storage is uncertain. The gradual, patchy senescence of early-successional trees accompanying this transition is comparable in severity to moderate disturbances such as silvicultural thinnings or insect outbreaks. While stand-replacing disturbance causes forests to temporarily become C sources, more moderate disturbances may inflict little to no decline in C sequestration. Identifying the disturbance severity at which net primary production (NPP) declines and the underlying mechanisms that drive forest C storage resistance to disturbance is increasingly important as moderate disturbances increase in frequency and extent across the region. The Forest Accelerated Succession ExperimenT (FASET) at the University of Michigan Biological Station subjected 39 ha of forest to moderate disturbance in 2008 by advancing age-related tree mortality through the stem girdling of early successional aspen and birch. Stand-scale disturbance severity, expressed as relative basal area of girdled aspen and birch, was 39% but plot-scale severity varied substantially within the experimental area (9 to 66% in 0.1 ha plots) because of the heterogeneous distribution of aspen and birch. We used this disturbance severity gradient to examine: 1) the relationship between NPP resilience and disturbance severity; 2) the disturbance severity at which NPP resilience prompts a shift in dominance from canopy to subcanopy vegetation; 3) how NPP resilience relates to disturbance-driven changes in resource-use efficiency, and 4) how disturbance severity shapes emerging forest communities We found that NPP is highly resilient to low to moderate levels of disturbance, but that production declines once a higher disturbance threshold is exceeded. Several complementary mechanisms, including canopy structural reorganization and the reallocation of growth-limiting light and

  7. 75 FR 48927 - Sierra National Forest, Bass Lake Ranger District, California, Fish Camp Project

    Science.gov (United States)

    2010-08-12

    .... Currently, vegetation within the Fish Camp Project has changed from one where frequent, low intensity fires... fire in the ecosystem. The forest-wide standards and guidelines state that ``vegetation within... clearance to protect them if a fast moving wildland fire were to move into the area. Vegetation in the Fish...

  8. Robust optimisation of forest transportation networks: a case study ...

    African Journals Online (AJOL)

    Robust optimisation of forest transportation networks: a case study. G Murphy, HC Stander. Abstract. Forest transportation costs are the major cost component for many forest product supply chains. In order to minimise these costs, many organisations have turned to optimisation models to guide decisions that are extremely ...

  9. Climate change and diverse dimensions of glacial lake outburst floods (GLOFs): Lake Palcacocha case study, Peru

    Science.gov (United States)

    Emmer, Adam; Walker-Crawford, Noah; Carey, Mark; Huggel, Christian; Verheyen, Roda; Wallimann-Helmer, Ivo

    2017-04-01

    Post-Little Ice Age (LIA) climate change has led to worldwide glacier retreat, formation and evolution of glacial lakes, occasionally followed by glacier lake outburst floods (GLOFs). Hundreds of GLOFs are documented throughout the 20th and 21st century, of which a certain number that caused massive downstream destruction and up to thousands of lives lost. Management of GLOF hazards and risks has typically been a local concern, focusing on the implementation of specific technical and engineering measures. Recently, however, researchers have realized that the complexity of both the risks and the socio-environmental context requires a broader understanding and response beyond the more typical local perception and management. The growing cumulative greenhouse gas (GHG) emissions, for instance, increase the anthropogenic contribution to glacier retreat, lake formation and growth and eventually to GLOF. GLOF hazard and risk management is inherently linked to the global scale from this perspective. It implies that additional important dimensions enter the debate, including ethical and legal questions about the responsibility for damage and loss due to GLOFs. Here we analyze the conditions at an emblematic case in Peru's Cordillera Blanca, which has made international headlines repeatedly since it first generated one of the world's most deadly GLOFs in 1941 to its present-day growth and instability. Situated upstream from the regional center of Huaráz (population ˜120,000), Lake Palcacocha has attracted significant attention in recent years within Peru and at an international level. Perspectives on Palcacocha lack truly cross-disciplinary research, missing more comprehensive insight. This contribution is unique for its analysis of diverse dimensions, which also provide a framework for other GLOF hazard, risk, and climate-related studies. The main aim of this constribution is to understand the links between them, their drivers and inhibitors. Four dimensions were studied

  10. Forest owner representation of forest management and perception of resource efficiency: a structural equation modeling study

    Directory of Open Access Journals (Sweden)

    Andrej Ficko

    2015-03-01

    Full Text Available Underuse of nonindustrial private forests in developed countries has been interpreted mostly as a consequence of the prevailing noncommodity objectives of their owners. Recent empirical studies have indicated a correlation between the harvesting behavior of forest owners and the specific conceptualization of appropriate forest management described as "nonintervention" or "hands-off" management. We aimed to fill the huge gap in knowledge of social representations of forest management in Europe and are the first to be so rigorous in eliciting forest owner representations in Europe. We conducted 3099 telephone interviews with randomly selected forest owners in Slovenia, asking them whether they thought they managed their forest efficiently, what the possible reasons for underuse were, and what they understood by forest management. Building on social representations theory and applying a series of structural equation models, we tested the existence of three latent constructs of forest management and estimated whether and how much these constructs correlated to the perception of resource efficiency. Forest owners conceptualized forest management as a mixture of maintenance and ecosystem-centered and economics-centered management. None of the representations had a strong association with the perception of resource efficiency, nor could it be considered a factor preventing forest owners from cutting more. The underuse of wood resources was mostly because of biophysical constraints in the environment and not a deep-seated philosophical objection to harvesting. The difference between our findings and other empirical studies is primarily explained by historical differences in forestland ownership in different parts of Europe and the United States, the rising number of nonresidential owners, alternative lifestyle, and environmental protectionism, but also as a consequence of our high methodological rigor in testing the relationships between the constructs

  11. Forest area in Costa Rica: a comparative study of tropical forest cover estimates over time.

    Science.gov (United States)

    Kleinn, Lenin; Corrales, Christoph; Morales, David

    2002-01-01

    Forest area figures. at a given point in time and for a given region of interest, differ considerably, affecting the calculation of deforestation rates and thus confuse the political and scientific discussion on the state and change of the resource forest. This article discusses the variation of published forest cover figures, using Costa Rica as an example. A list of published figures on the forest cover of Costa Rica from 1940 onwards is analyzed. Reasons for the differences are hypothesized and discussed. These differences are mainly in the definition of forest and forest classes included, in the type of the studies conducted (mapping and/or sampling), in the precision of the estimates, and in the information sources used. It is concluded that part of the problem is inherent in the nature of the resource 'forest'. Quality and completeness of the presentation of the forest cover estimates are a clue to their correct understanding and interpretation. The latter point being especially relevant, as forest cover data have both a technical-scientific and a political meaning and are used as relevant arguments in many discussions. In the example of Costa Rica, a general downward trend is observed up to about 1985/1990, whereas after that forest area figures are on the average at a markedly higher level. Some hypotheses for this change in the trend are discussed.

  12. DETERMINATION OF DIFFERENT STAKEHOLDER’S THOUGHT REGARDING THE FOREST RESOURCES AND FOREST RESOURCES SUSTAINABLE MANAGEMENT: A Case Study in Maçka State Forest Enterprise

    Directory of Open Access Journals (Sweden)

    Atakan Öztürk

    2005-04-01

    Full Text Available This study aimed to determine thoughts and views of stakeholders regarding the forest resources and management in Turkish Forestry. Maçka State Forest Enterprise under Trabzon Forest Regional Directorate was chosen as research area. Six different groups involving urban, rural, managerial, industrial, and recreational stakeholders as well as non-governmental organizations were determined. Interview and public survey methods and Khi-square test were used to attain the aim of the study. The main results were that the forest enterprise was perceived as the rich one with regard to forest existence and, it was put forward pessimistic though for forest future in the forest enterprise and, non-wood forest values were seen more important than the wood values by the stakeholders. The results of the study taken into account in forest resource planning would provide a contribution to sustainable forest resources management for the Maçka State Forest Enterprise.

  13. Environmental research programme. Ecological research. Annual report 1994. Urban-industrial landscapes, forests, agricultural landscapes, river and lake landscapes, terrestrial ecosystem research, environmental pollution and health

    International Nuclear Information System (INIS)

    1995-01-01

    In the annual report 1994 of the Federal Ministry of Research and Technology, the points of emphasis of the ecological research programme and their financing are discussed. The individual projects in the following subject areas are described in detail: urban-industrial landscapes, forests, agricultural landscapes, river and lake landscapes, other ecosystems and landscapes, terrestrial ecosystem research, environmental pollution and human health and cross-sectional activities in ecological research. (vhe) [de

  14. Vertical mixing as a determinant of trophic status in deep lakes: a case study from two lakes south of the Alps (Lake Garda and Lake Iseo

    Directory of Open Access Journals (Sweden)

    Paolo CORDELLA

    2003-09-01

    Full Text Available The identification of the factors and mechanisms determining a particular lake’s typology is crucial for the correct interpretation of trophic evolution. Nutrient concentrations are not the only properties which determine the trophic characteristics of lakes; others, such as morphometry, hydrology and climatic conditions, also have a major influence on the development of algal biomass and species composition. Large, deep lakes belong to a well defined typology. Their trophic status depends not only on algal nutrient loads, but also on the extent of the spring vertical mixing and renewal time. These factors are closely interrelated, for the actual renewal time approaches the theoretical renewal time only during the complete overturn. This paper compares the influence of different circulation patterns on the trophic status of two deep subalpine lakes with contrasting mixing characteristics. Lake Garda is the largest lake in Italy (S=368 km2, V=49 km3, Zmax=350 m. It is characterised by irregular circulation events (oligomixis; during the 1990s, complete homogenisation of the water column occurred in 1991 and 1999-2000. The years between these episodes showed an increase of hypolimnetic temperatures and a progressive vertical stratification of nutrients. Full overturn episodes were characterised by a sudden decrease of temperature and complete homogenisation of the chemical and physical variables along the water column, with a corresponding increase of nutrients and algal biomasses at the surface. In contrast, the last mixing involving the deepest waters in Lake Iseo (S= 60,9 km2, V=7,6 km3, Zmax=251 m occurred at the beginning of the 1980s, after which the reduced water renewal and the high trophic level resulted in a marked decrease in oxygen concentrations and in the establishment of conditions of anoxia during the 1990s. At present the lake is meromictic. In 1999 and 2000, when a complete overturn was observed in lakes Maggiore and Como as

  15. Impact of soil sorption characteristics and bedrock composition on phosphorus concentrations in two Bohemian Forest lakes

    Czech Academy of Sciences Publication Activity Database

    Kaňa, Jiří; Kopáček, Jiří

    2006-01-01

    Roč. 173, 1-4 (2006), s. 243-259 ISSN 0049-6979 R&D Projects: GA ČR(CZ) GA206/03/1583; GA AV ČR(CZ) 1QS600170504 Grant - others:EC(XE) GOCE-CT-2003-505540; MSM(CZ) 6007665801 Institutional research plan: CEZ:AV0Z60170517 Keywords : acidification * aluminium * forest soils Subject RIV: DJ - Water Pollution ; Quality Impact factor: 1.205, year: 2006

  16. Ubiquitous influence of wildfire emissions and secondary organic aerosol on summertime atmospheric aerosol in the forested Great Lakes region

    Science.gov (United States)

    Gunsch, Matthew J.; May, Nathaniel W.; Wen, Miao; Bottenus, Courtney L. H.; Gardner, Daniel J.; VanReken, Timothy M.; Bertman, Steven B.; Hopke, Philip K.; Ault, Andrew P.; Pratt, Kerri A.

    2018-03-01

    Long-range aerosol transport affects locations hundreds of kilometers from the point of emission, leading to distant particle sources influencing rural environments that have few major local sources. Source apportionment was conducted using real-time aerosol chemistry measurements made in July 2014 at the forested University of Michigan Biological Station near Pellston, Michigan, a site representative of the remote forested Great Lakes region. Size-resolved chemical composition of individual 0.5-2.0 µm particles was measured using an aerosol time-of-flight mass spectrometer (ATOFMS), and non-refractory aerosol mass less than 1 µm (PM1) was measured with a high-resolution aerosol mass spectrometer (HR-AMS). The field site was influenced by air masses transporting Canadian wildfire emissions and urban pollution from Milwaukee and Chicago. During wildfire-influenced periods, 0.5-2.0 µm particles were primarily aged biomass burning particles (88 % by number). These particles were heavily coated with secondary organic aerosol (SOA) formed during transport, with organics (average O/C ratio of 0.8) contributing 89 % of the PM1 mass. During urban-influenced periods, organic carbon, elemental carbon-organic carbon, and aged biomass burning particles were identified, with inorganic secondary species (ammonium, sulfate, and nitrate) contributing 41 % of the PM1 mass, indicative of atmospheric processing. With current models underpredicting organic carbon in this region and biomass burning being the largest combustion contributor to SOA by mass, these results highlight the importance for regional chemical transport models to accurately predict the impact of long-range transported particles on air quality in the upper Midwest, United States, particularly considering increasing intensity and frequency of Canadian wildfires.

  17. LIMNOLOGY, LAKE BASINS, LAKE WATERS

    Directory of Open Access Journals (Sweden)

    Petre GÂŞTESCU

    2009-06-01

    Full Text Available Limnology is a border discipline between geography, hydrology and biology, and is also closely connected with other sciences, from it borrows research methods. Physical limnology (the geography of lakes, studies lake biotopes, and biological limnology (the biology of lakes, studies lake biocoenoses. The father of limnology is the Swiss scientist F.A. Forel, the author of a three-volume entitled Le Leman: monographie limnologique (1892-1904, which focuses on the geology physics, chemistry and biology of lakes. He was also author of the first textbook of limnology, Handbuch der Seenkunde: allgemeine Limnologie,(1901. Since both the lake biotope and its biohydrocoenosis make up a single whole, the lake and lakes, respectively, represent the most typical systems in nature. They could be called limnosystems (lacustrine ecosystems, a microcosm in itself, as the American biologist St.A. Forbes put it (1887.

  18. A survey of medicinal plants around upper Songkhla lake, Thailand ...

    African Journals Online (AJOL)

    Background: Upper Songkhla Lake, a single lagoon of Thailand, is surrounded by sandy, mangrove, and swamp forests. Many plants growing in these areas have medicinal properties, however they have never been investigated. The aim of this study was to explore medicinal plants from upper Songkhla Lake, Songkhla ...

  19. Modeling CO2 emissions from Arctic lakes: Model development and site-level study

    Science.gov (United States)

    Tan, Zeli; Zhuang, Qianlai; Shurpali, Narasinha J.; Marushchak, Maija E.; Biasi, Christina; Eugster, Werner; Walter Anthony, Katey

    2017-09-01

    Recent studies indicated that Arctic lakes play an important role in receiving, processing, and storing organic carbon exported from terrestrial ecosystems. To quantify the contribution of Arctic lakes to the global carbon cycle, we developed a one-dimensional process-based Arctic Lake Biogeochemistry Model (ALBM) that explicitly simulates the dynamics of organic and inorganic carbon in Arctic lakes. By realistically modeling water mixing, carbon biogeochemistry, and permafrost carbon loading, the model can reproduce the seasonal variability of CO2 fluxes from the study Arctic lakes. The simulated area-weighted CO2 fluxes from yedoma thermokarst lakes, nonyedoma thermokarst lakes, and glacial lakes are 29.5, 13.0, and 21.4 g C m-2 yr-1, respectively, close to the observed values (31.2, 17.2, and 16.5 ± 7.7 g C m-2 yr-1, respectively). The simulations show that the high CO2 fluxes from yedoma thermokarst lakes are stimulated by the biomineralization of mobilized labile organic carbon from thawing yedoma permafrost. The simulations also imply that the relative contribution of glacial lakes to the global carbon cycle could be the largest because of their much larger surface area and high biomineralization and carbon loading. According to the model, sunlight-induced organic carbon degradation is more important for shallow nonyedoma thermokarst lakes but its overall contribution to the global carbon cycle could be limited. Overall, the ALBM can simulate the whole-lake carbon balance of Arctic lakes, a difficult task for field and laboratory experiments and other biogeochemistry models.

  20. Contributions of studies on experimental forests to hydrology and watershed management [Chapter 14

    Science.gov (United States)

    Gerald J. Gottfried; Peter F. Ffolliott; Kenneth N. Brooks; Randall K. Kolka; Carol B. Raish; Daniel G. Neary

    2014-01-01

    The link between healthy forests and watersheds and healthy streamflow and quality water is universally recognized. The major rivers of the USA originate in the forested mountains of the western and eastern USA and the glaciated regions of the Lake States and Great Plains and produce almost two-thirds of the nation’s clean water supply. Original logging and...

  1. Threats to private forest lands in the U.S.A.: a forests on the edge study

    Science.gov (United States)

    Mark H. Hatfield; Ronald E. McRoberts; Dacia M. Meneguzzo; Sara. Comas

    2010-01-01

    The Forests on the Edge project, sponsored by the USDA Forest Service, uses geographic information systems to construct and analyze maps depicting threats to the contributions of America’s private forest lands. For this study, watersheds across the conterminous United States are evaluated with respect to the amount of their private forest land. Watersheds with at least...

  2. The Impact of the Forest and Forest Industry on the Environment: A Study of Bibliographic Coverage. Bibliographic Series No. 4.

    Science.gov (United States)

    Oyler, David K.; McKay, Michael W.

    A citation study investigated the coverage by abstracting and indexing services of literature dealing with the environmental effects of the forest and forest products industries, the impact of man on the forest ecology, and methods for maximizing forest tree utilization. A search of nine secondary sources (abstracting and indexing services)…

  3. Snowmelt timing, phenology, and growing season length in conifer forests of Crater Lake National Park, USA

    Science.gov (United States)

    O'Leary, Donal S.; Kellermann, Jherime L.; Wayne, Chris

    2018-02-01

    Anthropogenic climate change is having significant impacts on montane and high-elevation areas globally. Warmer winter temperatures are driving reduced snowpack in the western USA with broad potential impacts on ecosystem dynamics of particular concern for protected areas. Vegetation phenology is a sensitive indicator of ecological response to climate change and is associated with snowmelt timing. Human monitoring of climate impacts can be resource prohibitive for land management agencies, whereas remotely sensed phenology observations are freely available at a range of spatiotemporal scales. Little work has been done in regions dominated by evergreen conifer cover, which represents many mountain regions at temperate latitudes. We used moderate resolution imaging spectroradiometer (MODIS) data to assess the influence of snowmelt timing and elevation on five phenology metrics (green up, maximum greenness, senescence, dormancy, and growing season length) within Crater Lake National Park, Oregon, USA from 2001 to 2012. Earlier annual mean snowmelt timing was significantly correlated with earlier onset of green up at the landscape scale. Snowmelt timing and elevation have significant explanatory power for phenology, though with high variability. Elevation has a moderate control on early season indicators such as snowmelt timing and green up and less on late-season variables such as senescence and growing season length. PCA results show that early season indicators and late season indicators vary independently. These results have important implications for ecosystem dynamics, management, and conservation, particularly of species such as whitebark pine ( Pinus albicaulis) in alpine and subalpine areas.

  4. Snowmelt timing, phenology, and growing season length in conifer forests of Crater Lake National Park, USA.

    Science.gov (United States)

    O'Leary, Donal S; Kellermann, Jherime L; Wayne, Chris

    2018-02-01

    Anthropogenic climate change is having significant impacts on montane and high-elevation areas globally. Warmer winter temperatures are driving reduced snowpack in the western USA with broad potential impacts on ecosystem dynamics of particular concern for protected areas. Vegetation phenology is a sensitive indicator of ecological response to climate change and is associated with snowmelt timing. Human monitoring of climate impacts can be resource prohibitive for land management agencies, whereas remotely sensed phenology observations are freely available at a range of spatiotemporal scales. Little work has been done in regions dominated by evergreen conifer cover, which represents many mountain regions at temperate latitudes. We used moderate resolution imaging spectroradiometer (MODIS) data to assess the influence of snowmelt timing and elevation on five phenology metrics (green up, maximum greenness, senescence, dormancy, and growing season length) within Crater Lake National Park, Oregon, USA from 2001 to 2012. Earlier annual mean snowmelt timing was significantly correlated with earlier onset of green up at the landscape scale. Snowmelt timing and elevation have significant explanatory power for phenology, though with high variability. Elevation has a moderate control on early season indicators such as snowmelt timing and green up and less on late-season variables such as senescence and growing season length. PCA results show that early season indicators and late season indicators vary independently. These results have important implications for ecosystem dynamics, management, and conservation, particularly of species such as whitebark pine (Pinus albicaulis) in alpine and subalpine areas.

  5. African Savanna-Forest Boundary Dynamics: A 20-Year Study.

    Science.gov (United States)

    Cuni-Sanchez, Aida; White, Lee J T; Calders, Kim; Jeffery, Kathryn J; Abernethy, Katharine; Burt, Andrew; Disney, Mathias; Gilpin, Martin; Gomez-Dans, Jose L; Lewis, Simon L

    2016-01-01

    Recent studies show widespread encroachment of forest into savannas with important consequences for the global carbon cycle and land-atmosphere interactions. However, little research has focused on in situ measurements of the successional sequence of savanna to forest in Africa. Using long-term inventory plots we quantify changes in vegetation structure, above-ground biomass (AGB) and biodiversity of trees ≥10 cm diameter over 20 years for five vegetation types: savanna; colonising forest (F1), monodominant Okoume forest (F2); young Marantaceae forest (F3); and mixed Marantaceae forest (F4) in Lopé National Park, central Gabon, plus novel 3D terrestrial laser scanning (TLS) measurements to assess forest structure differences. Over 20 years no plot changed to a new stage in the putative succession, but F1 forests strongly moved towards the structure, AGB and diversity of F2 forests. Overall, savanna plots showed no detectable change in structure, AGB or diversity using this method, with zero trees ≥10 cm diameter in 1993 and 2013. F1 and F2 forests increased in AGB, mainly as a result of adding recruited stems (F1) and increased Basal Area (F2), whereas F3 and F4 forests did not change substantially in structure, AGB or diversity. Critically, the stability of the F3 stage implies that this stage may be maintained for long periods. Soil carbon was low, and did not show a successional gradient as for AGB and diversity. TLS vertical plant profiles showed distinctive differences amongst the vegetation types, indicating that this technique can improve ecological understanding. We highlight two points: (i) as forest colonises, changes in biodiversity are much slower than changes in forest structure or AGB; and (ii) all forest types store substantial quantities of carbon. Multi-decadal monitoring is likely to be required to assess the speed of transition between vegetation types.

  6. Spatial variation in lake benthic macroinvertebrate ecological assessment: a synthesis of European case studies

    DEFF Research Database (Denmark)

    Sandin, Leif Leonard; Solimini, Angelo G.

    2012-01-01

    This paper summarizes eight case studies that were analysed as part of the research theme ``lake benthic macroinvertebrates'' forming part of the EU-funded WISER project ``Water bodies in Europe: Integrative Systems to assess Ecological status and Recovery''. The relationships between lake benthi...... and our aim is to provide useful information for designing monitoring programs and invertebrate based ecological classification tools with the ultimate aim to improve a sound management of European lake ecosystems....

  7. Modeling CO 2 emissions from Arctic lakes: Model development and site-level study: MODELING CO 2 EMISSIONS FROM ARCTIC LAKES

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Zeli [Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette Indiana USA; Now at Pacific Northwest National Laboratory, Richland Washington USA; Zhuang, Qianlai [Department of Earth, Atmospheric, and Planetary Sciences, Purdue University, West Lafayette Indiana USA; Department of Agronomy, Purdue University, West Lafayette Indiana USA; Shurpali, Narasinha J. [Department of Environmental and Biological Science, University of Eastern Finland, Kuopio Finland; Marushchak, Maija E. [Department of Environmental and Biological Science, University of Eastern Finland, Kuopio Finland; Biasi, Christina [Department of Environmental and Biological Science, University of Eastern Finland, Kuopio Finland; Eugster, Werner [Department of Environmental Systems Science, ETH Zurich, Zurich Switzerland; Walter Anthony, Katey [Water and Environmental Research Center, University of Alaska Fairbanks, Fairbanks Alaska USA

    2017-09-01

    Recent studies indicated that Arctic lakes play an important role in receiving, processing, and storing organic carbon exported from terrestrial ecosystems. To quantify the contribution of Arctic lakes to the global carbon cycle, we developed a one-dimensional process-based Arctic Lake Biogeochemistry Model (ALBM) that explicitly simulates the dynamics of organic and inorganic carbon in Arctic lakes. By realistically modeling water mixing, carbon biogeochemistry, and permafrost carbon loading, the model can reproduce the seasonal variability of CO2 fluxes from the study Arctic lakes. The simulated area-weighted CO2 fluxes from yedoma thermokarst lakes, non-yedoma thermokarst lakes and glacial lakes are 29.5 g C m-2 yr-1, 13.0 g C m-2 yr-1 and 21.4 g C m-2 yr-1, respectively, close to the observed values (31.2 g C m-2 yr-1, 17.2 g C m-2 yr-1 and 16.5±7.7 g C m-2 yr-1, respectively). The simulations show that the high CO2 fluxes from yedoma thermokarst lakes are stimulated by the biomineralization of mobilized labile organic carbon from thawing yedoma permafrost. The simulations also imply that the relative contribution of glacial lakes to the global carbon cycle could be the largest because of their much larger surface area and high biomineralization and carbon loading. According to the model, sunlight-induced organic carbon degradation is more important for shallow non-yedoma thermokarst lakes but its overall contribution to the global carbon cycle could be limited. Overall, the ALBM model can simulate the whole-lake carbon balance of Arctic lakes, a difficult task for field and laboratory experiments and other biogeochemistry models.

  8. Hessian forest ecosystem study. Forest report 2005. Weather, oaks; Waldoekosystemstudie Hessen. Waldzustandsbericht 2005. Witterung, Eiche

    Energy Technology Data Exchange (ETDEWEB)

    Paar, U.; Gawehn, P.; Scheler, B.; Schmidt, M.; Schoenfelder, E.; Eichhorn, J. (comps.) [Hessen-Forst FIV - Forsteinrichtung, Information, Versuchswesen, Hannoversch Muenden (Germany). Fachgebiet fuer Waldoekosystemstudie Hessen/Forsthydrologie

    2005-07-01

    The Hessian Forest Ecosystem Study aims to document and explore changes of forest ecosystems as a result of emissions and climatic influences. Thus, it contributes importantly to a multifunctional and sustainable forest management. Crown condition assessment results show only slight differences compared to the previous year (over all defoliation 2004: 25%, 2005: 26%). Vitality of oak proved a significant increase of defoliation, closely correlated to insect damage in 2005. Crown condition of oak is worse in the Hessian Rhein-Main area compared to the whole country. In contradiction to other species beech shows some regeneration in 2005. Deposition of sulfur and acid components has been on a low level. A high deposition of nitrogen compounds needs further reduction. Long term monitoring of forest ecosystems allows interpretation of climate based effects on forests. (orig.)

  9. Measuring the Quality of the Lakeside Tourist Destinations: Case Study of Lake Palić and Lake Srebrno (Serbia

    Directory of Open Access Journals (Sweden)

    Jelica J. MARKOVIĆ

    2015-10-01

    Full Text Available The purpose of this study is to determine the dimensions of the lakeside tourist destinations quality through the cases of Lake Palić and Lake Srebrno (Serbia, by interviewing daily visitors and tourists and to determine which dimensions of quality have a crucial impact on the overall satisfaction of daily visitors and tourists. Various models have been developed to measure quality. In this paper, the quality is measured by the model that is appropriate for lakeside tourist destinations, developed by Ryan, Huimin, and Chon (2010. Five dimensions of quality were identified and named as: additional tourist infrastructure, lake water quality, natural environment, hospitality and cleanness of the place. The results showed that the measured quality model largely predicts overall satisfaction of daily visitors and tourists on the destination. The dimension lake water quality has the most effects on the overall satisfaction. Further research could use this research by adding some other quality dimensions into consideration (e.g. quality of service, situational conditions, destination management in examining the effect of destination’s quality on satisfaction of daily visitors and tourists. The research is important to managers of lakeside tourist destinations who tend to have highly satisfied guests and who work on promotion and improvement of destination quality.

  10. Ecobiological studies of the freshwater lakes at Schirmacher Oasis, Antarctica

    Digital Repository Service at National Institute of Oceanography (India)

    Verlecar, X.N.; Dhargalkar, V.K.; Matondkar, S.G.P.

    were dominant in some lakes. Based on these characteristics the lakes were grouped as oligotrophic in nature. Organic carbon content of sediment was low, ranging from 0.05 to 1.8% and consequently the faunal density was also low. Protozoans, Nematodes...

  11. Impacts of population growth and economic development on water quality of a lake: case study of Lake Victoria Kenya water.

    Science.gov (United States)

    Juma, Dauglas Wafula; Wang, Hongtao; Li, Fengting

    2014-04-01

    Anthropogenic-induced water quality pollution is a major environmental problem in freshwater ecosystems today. As a result of this, eutrophication of lakes occurs. Population and economic development are key drivers of water resource pollution. To evaluate how growth in the riparian population and in the gross domestic product (GDP) with unplanned development affects the water quality of the lake, this paper evaluates Lake Victoria Kenyan waters basin. Waters quality data between 1990 and 2012 were analyzed along with reviews of published literature, papers, and reports. The nitrate-nitrogen (NO3-N), soluble phosphorus (PO4-P), chlorophyll a, and Secchi transparencies were evaluated as they are key water quality indicators. The NO3-N increased from 10 μg l(-1) in 1990 to 98 μg 1(-1) in 2008, while PO4-P increased from 4 μg l(-1) in 1990 to 57 μg l(-1) in 2008. The population and economic growth of Kenya are increasing with both having minimums in 1990 of 24.143 million people and 12.18 billion US dollars, to maximums in 2010 of 39.742 million people and 32.163 billion US dollars, respectively. A Secchi transparency is reducing with time, indicating an increasing pollution. This was confirmed by an increase in aquatic vegetation using an analysis of moderate resolution imaging spectroradiometer (MODIS) images of 2000 and 2012 of Kenyan waters. This study found that increasing population and GDP increases pollution discharge thus polluting lakes. One of major factors causing lake water pollution is the unplanned or poor waste management policy and service.

  12. Studies on the phytoplankton of the deep subalpine Lake Iseo

    Directory of Open Access Journals (Sweden)

    Rosario MOSELLO

    2003-08-01

    Full Text Available This paper reports the results of investigations carried out on the chemical characteristics and phytoplankton community of Lake Iseo. Samplings were performed on a monthly basis from 1998 to 2000. At least three main algal groups dominated the community throughout the study period. The large Bacillariophyceae were dominant mainly during late winter and early spring (Aulacoseira spp., Melosira varians, Asterionella formosa, with few species able to maintain occasional positive growth also during mid summer and/or autumn (Fragilaria crotonensis and Diatoma elongatum. The thermal stability of the water column and silica depletion were the main factors responsible for the decline of the large spring diatoms. The subsequent growth of Mougeotia sp. (Conjugatophyceae was favoured by its lower sinking rate and resistance to increasing grazing pressure by the dominant copepods (Copidodiaptomus steueri and cladocerans (Daphnia hyalina × galeata. Among the cyanobacteria, the greater development of Planktothrix rubescens in the autumn months, with conditions of vertical homogenisation and decreasing Zeu/Zmix ratios, was favoured by its ability to survive at low light irradiances. The temporal replacement of these three groups constitutes the main sequence of the annual phytoplankton succession in Lake Iseo. A large development of other algal groups was recorded only in one or two of the three study years (e.g. Dinophyceae and Chlorococcales. The changes observed in the annual phytoplankton development are discussed in the light of differences in the spring fertilisation of the waters, caused by differences in the depth of the layer involved in the late winter and spring vertical mixing.

  13. Studies of the Woody Vegetation of the Welor Forest Reserve ...

    African Journals Online (AJOL)

    The Welor area has been classified as a forest reserve since 1935 while waiting for the outcome of studies for its appropriate exploitation based on its biological potential. Due to lack of information on this potential, the plant resources of this forest reserve have been used improperly and excessively. The present study aims ...

  14. Front Range Forest Health Partnership Phase 1 feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Volkin, P

    1998-09-01

    The Front Range Forest Health Partnership is an alliance of individuals, citizen groups, federal, state, private, and nonprofit organizations that formed to promote forest health restoration and reduce fire risks on Colorado's Front Range. The partnership promotes selective thinning to restore forest health and supports economically feasible end uses for wood waste materials. The Phase I study was initiated to determine the environmental and economic feasibility of using wood wastes from forested and urban areas for the production of fuel-grade ethanol.

  15. Bibliography of U.S. Geological Survey studies of lakes and reservoirs; the first 100 years

    Science.gov (United States)

    Winter, Thomas C.

    1982-01-01

    For more than 100 years, the U.S. Geological Survey has pursued its mission of assessing and mapping the earth resources of the United States, including assessment of the Nation's water resources. Although the Survey has never been a water-management or development agency, it has assisted agencies that are responsible for such developments, and commonly provides data and information for such purposes. Because reservoirs are an intergral part of most water-development projects, the Survey has been involved in reservoir-related studies since the 1880's. The largest and longest involvement has centered on providing information on streamflows and sediment transport related to existing and proposed reservoirs. During the late 1940's, the Survey greatly expanded its activities in evaporation research. More recently, ground water, including bank storage, has gained increased attention. Most of these studies were related primarily to questions of water quantity, and the Survey continues to be involved in studies of physical hydrology. In addition, in response to the increased concern with environmental quality during the past 20 years, the number of Survey studies of the chemical and biological aspects of lakes and reservoirs have increased considerably. Prompted by the recent Centennial (1879-1979) of the U.S. Geological Survey, it is appropriate to assess the Survey's contributions to the hydrology of lakes and reservoirs. Both natural lakes and manmade reservoirs are included in this report. 1 This report includes studies in which lakes or reservoirs are the principal topics. It does not include reports of general water resources of an area in which lakes are discussed as part of that area. This report also does not include data reports in which the data are merely tabulated. The types of reports listed herein include studies of existing or proposed water bodies and associated fluxes of water to and from these water bodies. This report does not include geological or

  16. Contaminant Monitoring Strategy for Henrys Lake, Idaho

    Energy Technology Data Exchange (ETDEWEB)

    John S. Irving; R. P. Breckenridge

    1992-12-01

    Henrys Lake, located in southeastern Idaho, is a large, shallow lake (6,600 acres, {approx} 17.1 feet maximum depth) located at 6,472 feet elevation in Fremont Co., Idaho at the headwaters of the Henrys Fork of the Snake River. The upper watershed is comprised of high mountains of the Targhee National Forest and the lakeshore is surrounded by extensive flats and wetlands, which are mostly privately owned. The lake has been dammed since 1922, and the upper 12 feet of the lake waters are allocated for downriver use. Henrys Lake is a naturally productive lake supporting a nationally recognized ''Blue Ribbon'' trout fishery. There is concern that increasing housing development and cattle grazing may accelerate eutrophication and result in winter and early spring fish kills. There has not been a recent thorough assessment of lake water quality. However, the Department of Environmental Quality (DEQ) is currently conducting a study of water quality on Henrys Lake and tributary streams. Septic systems and lawn runoff from housing developments on the north, west, and southwest shores could potentially contribute to the nutrient enrichment of the lake. Many houses are on steep hillsides where runoff from lawns, driveways, etc. drain into wetland flats along the lake or directly into the lake. In addition, seepage from septic systems (drainfields) drain directly into the wetlands enter groundwater areas that seep into the lake. Cattle grazing along the lake margin, riparian areas, and uplands is likely accelerating erosion and nutrient enrichment. Also, cattle grazing along riparian areas likely adds to nutrient enrichment of the lake through subsurface flow and direct runoff. Stream bank and lakeshore erosion may also accelerate eutrophication by increasing the sedimentation of the lake. Approximately nine streams feed the lake (see map), but flows are often severely reduced or completely eliminated due to irrigation diversion. In addition, subsurface

  17. Robust optimisation of forest transportation networks: a case study ...

    African Journals Online (AJOL)

    Forest transportation costs are the major cost component for many forest product supply chains. In order to minimise these costs, many organisations have turned ... The simulation results are then evaluated for robustness by means of seven robustness performance measures. For our case study, the results show that (1) the ...

  18. Forest Service patrol captain and patrol commanders report: nationwide study

    Science.gov (United States)

    Deborah J. Chavez; Joanne F. Tynon

    2007-01-01

    This is the third in a series of studies to evaluate perceptions of USDA Forest Service law enforcement personnel of the roles, responsibilities, and issues entailed in their jobs. An e-mail survey was administered to the 79 Forest Service patrol captains and patrol commanders (PCs) across the United States. Seventy completed and returned the questionnaire....

  19. SF6 ventilation study at Agnew Lake Mines, Ontario

    International Nuclear Information System (INIS)

    1979-03-01

    In September 1978, James F. MacLaren Limited was awarded a contract by the Canada Centre for Mineral and Energy Technology (CANMET) to undertake a ventilation study at an underground uranium mine using sulphur hexafluoride (SF 6 ) as a tracer gas. The mine selected for the study was that of Agnew Lake Mines Limited in Northern Ontario. This is a relatively new mine with the combined mine/mill facilities first operational in mid-1977. Uranium is recovered from broken ore by in-situ leaching. The ventilation study was divided into two phases. A laboratory study was undertaken to develop a practical sampling technique, provide an evaluation of the logistics of long range sample transport and develop a laboratory analytical technique. Field programmes demonstrated the SF 6 tracer gas technique for mine ventilation trouble-shooting with the intent of providing information which will lead to more efficient use of existing mine ventilation capacity. This report outlines the findings of the laboratory study and the two field programmes

  20. Marketing of non-wood forest products: Case study of the enterprise for forest mushroom processing

    Directory of Open Access Journals (Sweden)

    Keča Ljiljana

    2009-01-01

    Full Text Available Under the impact of climate changes it is increasingly obvious that forestry should rely more strongly on the multi­functional character of the managed resources. In addition to wood, there is a series of non­wood products and services offered by forests. Non­wood forest products and services consist of various fruits of forest trees and shrubs, mushrooms, various objects made of non­wood material, and especially forest social services, such as recreation, tourism, hunting, photo­safari, etc. This paper presents a marketing analysis on the example of the enterprise dealing with the purchase, processing and sale of wild mushrooms and products made of mushrooms. The study applies a modern methodological approach implemented in similar researches.

  1. Limnological Studies at Eau Galle Lake, Wisconsin. Report 1. Introduction and Water Quality Monitoring Studies.

    Science.gov (United States)

    1985-03-01

    Ground water, which provides all of the potable water used in the Eau Galle River watershed, is contained in sandstone aquifers that underlie the...I D..L 4. TITLE (d &abliaU.) S. TYPE OF REPORT & PERIOD COVERED LIMNOLOGICAL STUDIES AT EAU GALLE LAKE, WISCONSIN; Report I of a series Report 1...CC40ORM 40 i"Wee 0011 N 0600404 &Rd IdeOW10 6Y black anm~w) - Eau Galle Lake, one of four Corps of Engineers reservoirs surveyed during the Environmental

  2. 77 FR 21522 - Lake Tahoe Basin Management Unit and Tahoe National Forest, CA; Calpeco 625 and 650 Electrical...

    Science.gov (United States)

    2012-04-10

    ... significant portion of the existing 625 Line would be realigned to a location that parallels Mount Watson Road... system. The existing north Lake Tahoe transmission system is a loop comprised of a series of 60 kV and... electrical circuit and is very similar to a watt. Purpose and Need for Action The north Lake Tahoe electric...

  3. Remote Characterization of Biomass Measurements: Case Study of Mangrove Forests

    Science.gov (United States)

    Fatoyinbo, Temilola E.

    2010-01-01

    Accurately quantifying forest biomass is of crucial importance for climate change studies. By quantifying the amount of above and below ground biomass and consequently carbon stored in forest ecosystems, we are able to derive estimates of carbon sequestration, emission and storage and help close the carbon budget. Mangrove forests, in addition to providing habitat and nursery grounds for over 1300 animal species, are also an important sink of biomass. Although they only constitute about 3% of the total forested area globally, their carbon storage capacity -- in forested biomass and soil carbon -- is greater than that of tropical forests (Lucas et al, 2007). In addition, the amount of mangrove carbon -- in the form of litter and leaves exported into offshore areas is immense, resulting in over 10% of the ocean's dissolved organic carbon originating from mangroves (Dittmar et al, 2006) The measurement of forest above ground biomass is carried out on two major scales: on the plot scale, biomass can be measured using field measurements through allometric equation derivation and measurements of forest plots. On the larger scale, the field data are used to calibrate remotely sensed data to obtain stand-wide or even regional estimates of biomass. Currently, biomass can be calculated using average stand biomass values and optical data, such as aerial photography or satellite images (Landsat, Modis, Ikonos, SPOT, etc.). More recent studies have concentrated on deriving forest biomass values using radar (JERS, SIR-C, SRTM, Airsar) and/or lidar (ICEsat/GLAS, LVIS) active remote sensing to retrieve more accurate and detailed measurements of forest biomass. The implementation of a generation of new active sensors (UAVSar, DesdynI, Alos/Palsar, TerraX) has prompted the development of new tecm'liques of biomass estimation that use the combination of multiple sensors and datasets, to quantify past, current and future biomass stocks. Focusing on mangrove forest biomass estimation

  4. Properties of soils and tree wood tissue across a Lake States sulfate deposition gradient.

    Science.gov (United States)

    Lewis F. Ohmann; David F. Grigal

    1991-01-01

    Presents the soil and tree wood tissue properties (mostly chemical) of the plots that were remeasured and sampled for a study of the relation between forest condition and wet sulfate deposition along the Lake States acidic deposition gradient.

  5. Exploratory studies into seasonal flow forecasting potential for large lakes

    Directory of Open Access Journals (Sweden)

    K. Sene

    2018-01-01

    Full Text Available In seasonal flow forecasting applications, one factor which can help predictability is a significant hydrological response time between rainfall and flows. On account of storage influences, large lakes therefore provide a useful test case although, due to the spatial scales involved, there are a number of modelling challenges related to data availability and understanding the individual components in the water balance. Here some possible model structures are investigated using a range of stochastic regression and transfer function techniques with additional insights gained from simple analytical approximations. The methods were evaluated using records for two of the largest lakes in the world – Lake Malawi and Lake Victoria – with forecast skill demonstrated several months ahead using water balance models formulated in terms of net inflows. In both cases slight improvements were obtained for lead times up to 4–5 months from including climate indices in the data assimilation component. The paper concludes with a discussion of the relevance of the results to operational flow forecasting systems for other large lakes.

  6. Exploratory studies into seasonal flow forecasting potential for large lakes

    Science.gov (United States)

    Sene, Kevin; Tych, Wlodek; Beven, Keith

    2018-01-01

    In seasonal flow forecasting applications, one factor which can help predictability is a significant hydrological response time between rainfall and flows. On account of storage influences, large lakes therefore provide a useful test case although, due to the spatial scales involved, there are a number of modelling challenges related to data availability and understanding the individual components in the water balance. Here some possible model structures are investigated using a range of stochastic regression and transfer function techniques with additional insights gained from simple analytical approximations. The methods were evaluated using records for two of the largest lakes in the world - Lake Malawi and Lake Victoria - with forecast skill demonstrated several months ahead using water balance models formulated in terms of net inflows. In both cases slight improvements were obtained for lead times up to 4-5 months from including climate indices in the data assimilation component. The paper concludes with a discussion of the relevance of the results to operational flow forecasting systems for other large lakes.

  7. Limnological controls on stable isotope records of late-holocene palaeoenvironment change in sw greenland: A paired lake study

    DEFF Research Database (Denmark)

    Olsen, Jesper; John Anderson, N.; Leng, M.J.

    2013-01-01

    Stable isotope records are increasingly being used in palaeoenvironmental studies of Arctic lakes. Here we compare stable isotope and elemental records (δ13C, δ15N, C/N) with high resolution XRF-derived geochemical and colour data from low Arctic lakes (SS1220 and SS85) in southwest Greenland. Lake...

  8. Ecosystem services of human-dominated watersheds and land use influences: a case study from the Dianchi Lake watershed in China.

    Science.gov (United States)

    Hou, Ying; Li, Bo; Müller, Felix; Chen, Weiping

    2016-11-01

    Watersheds provide multiple ecosystem services. Ecosystem service assessment is a promising approach to investigate human-environment interaction at the watershed scale. The spatial characteristics of ecosystem services are closely related to land use statuses in human-dominated watersheds. This study aims to investigate the effects of land use on the spatial variations of ecosystem services at the Dianchi Lake watershed in Southwest China. We investigated the spatial variations of six ecosystem services-food supply, net primary productivity (NPP), habitat quality, evapotranspiration, water yield, and nitrogen retention. These services were selected based on their significance at the Dianchi Lake watershed and the availability of their data. The quantification of these services was based on modeling, value transference, and spatial analysis in combination with biophysical and socioeconomic data. Furthermore, we calculated the values of ecosystem services provided by different land use types and quantified the correlations between ecosystem service values and land use area proportions. The results show considerable spatial variations in the six ecosystem services associated with land use influences in the Dianchi Lake watershed. The cropland and forest land use types had predominantly positive influences on food productivity and NPP, respectively. The rural residential area and forest land use types reduced and enhanced habitat quality, respectively; these influences were identical to those of evapotranspiration. Urban area and rural residential area exerted significantly positive influences on water yield. In contrast, water yield was negatively correlated with forest area proportion. Finally, cropland and forest had significantly positive and negative influences, respectively, on nitrogen retention. Our study emphasizes the importance of consideration of the influences from land use composition and distribution on ecosystem services for managing the ecosystems of

  9. STUDY OF PARAMETERS OF THE ICE-THERMAL REGIME OF LAKE BAIKAL USING REMOTE METHODS

    Directory of Open Access Journals (Sweden)

    E. N. Sutyrina

    2017-01-01

    Full Text Available The surface temperature of the water and the characteristics of the ice cover are important parameters of the state of the ecosystem of the lake and one of the most important indicators that allow us to identify climate change. Dimensions of Lake Baikal with an area of 31.7 thousand sq. kilometers make it reasonable to use the data of satellite remote sensing to study the characteristics of its ice-thermal regime. The purpose of this investigation was to study the features of the spatiotemporal distribution of the parameters of the ice-thermal regime of Lake Baikal using AVHRR (Advanced Very High Resolution Radiometer radiometer data for the period of 1998-2016.The paper describes the developed approach to mapping the stages of melting and destruction of the snow-ice cover on Baikal Lake in the spring and the method for mapping the surface temperature of the lake in an ice-free period according to AVHRR data. Samples of compiled schematic maps of the ice situation and of temperature distribution on the lake surface are given. Based on the obtained cartographic materials, the specificity of ice disappearance of the water areas of the Southern, Central and Northern basins of Lake Baikal has been studied. And it was found that the interannual fluctuations in the timing of the ice disappearance on the given water areas are in antiphase with the interannual fluctuations in the value of the Arctic Oscillation Index. Schematic temperature maps were used to study the intra-annual and interannual variability in the temperature distribution of Lake Baikal’s surface and it was revealed that the greatest interannual variability of temperature on its surface is observed in August, which is characterized by the maximum warming of the surface of the water body. Also, the contribution of several significant factors to the formation of temperature fields on the surface of Lake Baikal was estimated. 

  10. Seepage study of six canals in Salt Lake County, Utah, 1982-1983

    Science.gov (United States)

    Herbert, L.R.; Cruff, R.W.; Waddell, K.M.

    1985-01-01

    A study of selected reaches of the Utah and Salt Lake, Utah Lake Distributing, Provo Reservoir, Draper Irrigation, East Jordan, and Jordan and Salt Lake City Canals in Salt Lake County, Utah, was made to determine gains or losses of flow in those reaches. Three to five sets of seepage measurements were made on each canal during 1982 or 1983. Adjustments for fluctuations in flow were made from information obtained from water-stage recorders operated at selected locations during the time of each seepage run.The study showed an overall net loss of about 9.5 cubic feet per second in the Utah and Salt Lake Canal, 11.0 cubic feet per second in the Utah Lake Distributing canal, 20.5 cubic feet per second in the Provo Reservoir canal, 1.5 cubic feet per second in the Draper Irrigation Canal, and 4.0 cubic feet per second in the East Jordan canal. It also showed a net gain of about 6.0 cubic feet per second in the Jordan and Salt Lake City Canal. The gains and losses are attributed primarily to the relation of the canals to the depth of the water table near the canals.

  11. Magnetic and gravity studies of Mono Lake, east-central, California

    Science.gov (United States)

    Athens, Noah D.; Ponce, David A.; Jayko, Angela S.; Miller, Matt; McEvoy, Bobby; Marcaida, Mae; Mangan, Margaret T.; Wilkinson, Stuart K.; McClain, James S.; Chuchel, Bruce A.; Denton, Kevin M.

    2014-01-01

    From August 26 to September 5, 2011, the U.S. Geological Survey (USGS) collected more than 600 line-kilometers of shipborne magnetic data on Mono Lake, 20 line-kilometers of ground magnetic data on Paoha Island, 50 gravity stations on Paoha and Negit Islands, and 28 rock samples on Paoha and Negit Islands, in east-central California. Magnetic and gravity investigations were undertaken in Mono Lake to study regional crustal structures and to aid in understanding the geologic framework, in particular regarding potential geothermal resources and volcanic hazards throughout Mono Basin. Furthermore, shipborne magnetic data illuminate local structures in the upper crust beneath Mono Lake where geologic exposure is absent. Magnetic and gravity methods, which sense contrasting physical properties of the subsurface, are ideal for studying Mono Lake. Exposed rock units surrounding Mono Lake consist mainly of Quaternary alluvium, lacustrine sediment, aeolian deposits, basalt, and Paleozoic granitic and metasedimentary rocks (Bailey, 1989). At Black Point, on the northwest shore of Mono Lake, there is a mafic cinder cone that was produced by a subaqueous eruption around 13.3 ka. Within Mono Lake there are several small dacite cinder cones and flows, forming Negit Island and part of Paoha Island, which also host deposits of Quaternary lacustrine sediments. The typical density and magnetic properties of young volcanic rocks contrast with those of the lacustrine sediment, enabling us to map their subsurface extent.

  12. Preliminary study on streamflow in forested and forest plantation experimental watersheds for water resources management

    International Nuclear Information System (INIS)

    Siti Aisah Shamsuddin; Marrynna Lion; Saiful Iskandar, K.; Norazuan, H.

    2006-01-01

    The future management of forests for water resources will be more important as population growth and demand for water resources increases. In Malaysia many lowland forests has been earmarked for agricultural crops, and timber concessionaires has moved towards the hillier region of the country where specific and costly logging techniques are required. Hence, planting timber trees, as an industrial timber plantation is an alternative to meet timber demands. Very few research on evaluation of the impact of forest clearance on hydrology attributes from newly established industrial timber plantations have been conducted. In 1989, experimental catchment at Bukit Tarek Tambahan Experimental Watershed (BTEW) was initiated to study the effects of land conversion from forest to industrial timber plantation on hydrological parameters changes. The BTEW is located in Compartment 41, Bukit Tarek Tambahan F. R. at Kerling, Selangor Malaysia. The study site was a regenerated secondary forest logged in 1963. The study area is divided into catchment C1 (32.8 ha) and C3 (12.5 ha). Catchment C1, act as a control whereas C3 is the experimental catchments. Catchment C3 was logged in 1999 and early 2000 and subsequently a forest plantation was established. The forest area in Catchment C3 was clear felled, and the residuals trees were burnt. Buffer zone was not established near the riverbanks. The plantation was established in catchment C3 with Hopea odorata in early 2004. Streamflow was measured continuously using the 120 degree V-notch weir at the outlet of each watershed (Weir 1 and Weir 3). The short time interval rainfall was also monitored. In this working paper, the main objective to analyze the data is to examine rainfall-runoff response of forested catchments before establishment of forest plantation. The preliminary study on discharge after the C3 was clear-felled using single storm hydrograph analysis shows that during the storm event, the quick flow runoff dominate the

  13. STUDYING FOREST ROOT SYSTEMS - AN OVERVIEW OF METHODOLOGICAL PROBLEMS

    Science.gov (United States)

    The study of tree root systems is central to understanding forest ecosystem carbon and nutrient cycles, nutrient and water uptake, C allocation patterns by trees, soil microbial populations, adaptation of trees to stress, soil organic matter production, etc. Methodological probl...

  14. 2008 USDA Forest Service Lidar: Sandy River Study Area

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Watershed Sciences, Inc. collected Light Detection and Ranging (LiDAR) data for the Sandy River study area in collaboration with the USDA Forest Service. The areas...

  15. Results from the Mayson Lake Hydrological Processes Study 2008 Summer Field Season

    Science.gov (United States)

    Carlyle-Moses, D. E.; McKee, A. J.; Lishman, C. E.; Giesbrecht, W. J.; Kinniburgh, S. M.

    2009-05-01

    The Mayson Lake Hydrological Processes Study area is located in the southern interior of British Columbia ˜ 60 km NNW of the City of Kamloops, British Columbia on the Thompson-Bonaparte Plateau (51.2° N, 120.4° W; 1260 m a.m.s.l.). During the summer of 2008 a series of projects were carried out in preparation for a larger, more detailed study of the impact forest disturbance and subsequent re-growth has on hydrological processes. Results from the 2008 field season suggest that canopy interception loss of rainfall in a mixed lodgepole pine (Pinus contorta var. latifolia Dougl.) - hybrid spruce (Picea glauca (Moench) Voss. x engelmanni Perry x Engelm.) - subalpine fir (Abies lasiocarpa (Hook.) Nutt.) stand, where pines were at the grey - attack stage of mountain pine beetle (Dendroctonus ponderosae Scolytidae) infestation, is comparable to healthy mature stands, but significantly greater (α = 0.05) than that from the burned stand. Canopy interception loss, throughfall and stemflow for 14 events totalling 50.1 mm were found to be 41.2, 58.7, and 0.1 % of rainfall, respectively. Near-surface (surface to 20 cm depth) soil moisture depletion was determined using weekly TDR measurements at 32 points in each plot during a two-month dry- down period (June 16 -August 18) in which only 30.8 mm of rain fell. Soil depletion was found to be ˜ 2.6 times greater from juvenile stands than from a clear-cut, while in the beetle infested stands soil depletion averaged ˜ 1.6 times greater than in the clear-cut. Assuming no deep drainage past a depth of 20 cm or lateral throughflow out of the study plots, actual evapotranspiration (AET) was estimated at 53.2 ± 4.0 mm from the clear-cut during the dry-down period, while from two healthy juvenile stands AET was estimated at 87.1 ± 7.0 and 87.8 ± 4.0 mm. In two beetle infested forests AET during the dry-down period was estimated at 63.4 ± 5.0 and 69.8 ± 3.2 mm. The larger AET losses from the juvenile stands compared to the clear

  16. Ecosystem and Social Construction: an Interdisciplinary Case Study of the Shurkul Lake Landscape in Khorezm, Uzbekistan.

    Directory of Open Access Journals (Sweden)

    Lisa Oberkircher

    2011-12-01

    Full Text Available Transformation of the Khorezm region of Uzbekistan from forested to agricultural landscapes resulted in the formation of hundreds of lakes, the dynamics of which are largely controlled by inputs from irrigation runoff waters. The importance of the ecological and socio-cultural dimensions of one of these lakes, Shurkul, is discussed in order to understand the connection between humans and their environment. Landscape is used as a boundary concept, and we combine quantitative methods of the natural sciences with qualitative methods of the social sciences to assess these dimensions of the lake landscape. In the ecological dimension, Shurkul performs a wide range of ecosystem services from wildlife habitat and foodweb support to the provision of fish, fodder, building material and grazing ground. In the socio-cultural dimension, the lake is part of local ecological knowledge, functions as a prestige object and recreational site, and is rooted in religious beliefs of the population as a symbol of God's benevolence. The Shurkul landscape may thus create a feeling of environmental connectedness and the desire to act in favor of the natural environment, which could be made use of in environmental education programs.

  17. 2010 Great Lakes Human Health Fish Tissue Study Fish Tissue Data Dictionary

    Science.gov (United States)

    The Office of Science and Technology (OST) is providing the fish tissue results from the 2010 Great Lakes Human Health Fish Tissue Study (GLHHFTS). This document includes the “data dictionary” for Mercury, PFC, PBDE and PCBs.

  18. The relationship between diversity and productivity in selected forests of the Lake States Region (USA): relative impact of species versus structural diversity

    Science.gov (United States)

    W. Keith Moser; Mark Hansen

    2009-01-01

    Ecological theory suggests that diversity and productivity (at some measure) are positively correlated, presumably because individuals engage in niche partitioning to occupy any unclaimed growing space. We examined this theory using inventory information from the U.S. Department of Agriculture, Forest Service, Forest Inventory and Analysis program. The study uses plot-...

  19. Biomass and element pools of understory vegetation in the catchments of Čertovo Lake and Plešné Lake in the Bohemian Forest

    Czech Academy of Sciences Publication Activity Database

    Svoboda, M.; Matějka, K.; Kopáček, Jiří

    2006-01-01

    Roč. 61, Suppl. 20 (2006), S509-S521 ISSN 0006-3088 R&D Projects: GA ČR GA206/03/1583 Grant - others:MA(CZ) NAZV QG50105 Institutional research plan: CEZ:AV0Z60170517 Keywords : Norway spruce forest * understory vegetation Subject RIV: EH - Ecology, Behaviour Impact factor: 0.213, year: 2006

  20. Real time forest fire warning and forest fire risk zoning: a Vietnamese case study

    Science.gov (United States)

    Chu, T.; Pham, D.; Phung, T.; Ha, A.; Paschke, M.

    2016-12-01

    Forest fire occurs seriously in Vietnam and has been considered as one of the major causes of forest lost and degradation. Several studies of forest fire risk warning were conducted using Modified Nesterov Index (MNI) but remaining shortcomings and inaccurate predictions that needs to be urgently improved. In our study, several important topographic and social factors such as aspect, slope, elevation, distance to residential areas and road system were considered as "permanent" factors while meteorological data were updated hourly using near-real-time (NRT) remotely sensed data (i.e. MODIS Terra/Aqua and TRMM) for the prediction and warning of fire. Due to the limited number of weather stations in Vietnam, data from all active stations (i.e. 178) were used with the satellite data to calibrate and upscale meteorological variables. These data with finer resolution were then used to generate MNI. The only significant "permanent" factors were selected as input variables based on the correlation coefficients that computed from multi-variable regression among true fire-burning (collected from 1/2007) and its spatial characteristics. These coefficients also used to suggest appropriate weight for computing forest fire risk (FR) model. Forest fire risk model was calculated from the MNI and the selected factors using fuzzy regression models (FRMs) and GIS based multi-criteria analysis. By this approach, the FR was slightly modified from MNI by the integrated use of various factors in our fire warning and prediction model. Multifactor-based maps of forest fire risk zone were generated from classifying FR into three potential danger levels. Fire risk maps were displayed using webgis technology that is easy for managing data and extracting reports. Reported fire-burnings thereafter have been used as true values for validating the forest fire risk. Fire probability has strong relationship with potential danger levels (varied from 5.3% to 53.8%) indicating that the higher

  1. Comparative studies of the nitrogen metabolism of phytoplankton and periphyton in oligotrophic lakes

    International Nuclear Information System (INIS)

    Axler, R.P.; Goldman, C.R.; Reuter, J.E.; Loeb, S.L.; Priscu, J.C.; Carlton, R.G.

    1983-01-01

    This report presents the preliminary data of limnological research at the meso-oligotrophic Castle Lake, CA and at the ultratrophic Lake Tahoe, CA-NEV, USA, during 1980 to 1981. The areas of study were effects of nutrients enrichment and deficiency on primary producers; nitrogen cycling and nitrogen metabolism of benthic and planktonic algae and whole-epilimnion enrichment with ammonium nitrate. Tracer techniques using 14 C- and 15 N-labelled compounds were employed in the study

  2. Laboratory studies of dissolved radiolabelled microcystin-LR in lake water

    DEFF Research Database (Denmark)

    Hyenstrand, Per; Rohrlack, Thomas; Beattie, Kenneth A

    2003-01-01

    The fate of dissolved microcystin-LR was studied in laboratory experiments using surface water taken from a eutrophic lake. Based on initial range finding, a concentration of 50 microg l(-1) dissolved 14C-microcystin-LR was selected for subsequent time-course experiments. The first was performed ...... fractions. The study demonstrated that biodegradation of dissolved microcystin-LR occurred in water collected at a lake surface with carbon dioxide as a major end-product....

  3. phytoplankton and nutrients studies in magu bay, speke gulf, lake ...

    African Journals Online (AJOL)

    LAKE VICTORIA, (TANZANIA) FOLLOWING THE 2001 PRINCIPAL RAIN ... endemic fish populations; thermal stratification .... nitrate/nitrite and ammonia had upward fluxes of. 12.8 ug nor-N tin1 and 6.0 pg NHf-N l'lh'l, respectively While soluble reactive Phosphorus and Silica did not show any net change with time.

  4. Ventilation Study of Proposed Ammunition Plant at Lake City Arsenal

    Science.gov (United States)

    1975-12-01

    34Principles of Ventilation," The Industrial Environment - its Evaluation & Control, U.S. Department of Health, Education and Welfare, 1973. 23. Natio’ial...Industrial Hyiene and Toxicolou, Intc.rs cience Publishers *inc., N.Y., 1958. 27. Sr-ericer, John, Safety Director, Lake City, Arsenal lndepene

  5. Qualitative Study Of Anopheles Species In Konduga Lake Area Of ...

    African Journals Online (AJOL)

    The investigation on Anopheles species in Konduga lake area, Borno State of Nigeria, was carried out to identify various Anopheles species prevalent in the area and to determine their relative population densities. Six Anopheles species were recorded, namely, A. gambiae, A. funestus, A. ziemanni, A. squamosus, ...

  6. A case study of lakes Kasu and Nyafie

    African Journals Online (AJOL)

    PROF.MIREKU

    suspended solids, dissolved solids and total solids. .... Temperature and pH were determined directly in the field using portable battery .... Dissolved solids. 1000 mg/L. BOD. <3 mg/L. COD. 250 mg/L. General water quality and seasonal variations within the lakes. The results in Tables 2, 3 and 4 show the general water ...

  7. Utilization of GIS modeling in geoenvironmental studies of Qaroun Lake, El Fayoum Depression, Egypt

    Science.gov (United States)

    Attia, Abdelaal H.; El-Sayed, Salah Abdelwahab; El-Sabagh, Moustafa E.

    2018-02-01

    Qaroun Lake, the study area, is a natural protectorate located at the northern part of El Fayoum Depression, Egypt. An integrated approach including hydrochemistry, mineralogy of sediments and GIS analysis and modeling was conducted in order to determine the different geoenvironmental parameters affecting the lake environmental system. Forty two environmental water and sediment samples were collected from the lake and relevant drains in 2013. The water samples were analyzed for major ions and trace elements and the sediment ones were analyzed for clay and non-clay minerals. This study showed that the saline water of the lake (31490 alkalies and strong acids. The order of ionic dominance was Na+ > Mg2+ > Ca2+ > K+ - Cl- > SO42- > HCO3- > CO32-. The water salt assemblages were KCl - NaCl - Na2SO4 - MgSO4 - CaSO4 - Ca(HCO3)2 reflecting a mixed water type. The contents of NaCl, Na2SO4 and MgSO4 salts were found to be fully controlled with the lake depths. The hydrogeochemical investigations revealed that the evaporation concentration is the primary process of the lake water evolution. The presence of trace elements in the lake water is essentially of allochtonous origin. The GIS-based maps indicated that the concentrations of Zn, Co, Mo, Pb, F and Cd elements in water had increased in the eastern part of the lake; meanwhile, the contents of NO3- ions had increased in the southwestern part indicating that these parts were the most vulnerable to the potential pollution with such elements. The XRD analysis revealed the existence of different mineral assemblages (quartz, kaolinite, goethite, calcite, halite, hematite, feldspar, gypsum, dolomite and saponite) in bottom sediments. The mineral concentrations varied greatly from place to another place along the lake and their distributions were asymmetric. The dominant minerals were the quartz and calcite. The mineralogical compositions of sediments were highly affected by the natural and man-mad activities. The most effective

  8. Scaling Forest Management Practices in Earth System Models: Case Study of Southeast and Pacific Northwest Forests

    Science.gov (United States)

    Pourmokhtarian, A.; Becknell, J. M.; Hall, J.; Desai, A. R.; Boring, L. R.; Duffy, P.; Staudhammer, C. L.; Starr, G.; Dietze, M.

    2014-12-01

    A wide array of human-induced disturbances can alter the structure and function of forests, including climate change, disturbance and management. While there have been numerous studies on climate change impacts on forests, interactions of management with changing climate and natural disturbance are poorly studied. Forecasts of the range of plausible responses of forests to climate change and management are need for informed decision making on new management approaches under changing climate, as well as adaptation strategies for coming decades. Terrestrial biosphere models (TBMs) provide an excellent opportunity to investigate and assess simultaneous responses of terrestrial ecosystems to climatic perturbations and management across multiple spatio-temporal scales, but currently do not represent a wide array of management activities known to impact carbon, water, surface energy fluxes, and biodiversity. The Ecosystem Demography model 2 (ED2) incorporates non-linear impacts of fine-scale (~10-1 km) heterogeneity in ecosystem structure both horizontally and vertically at a plant level. Therefore it is an ideal candidate to incorporate different forest management practices and test various hypotheses under changing climate and across various spatial scales. The management practices that we implemented were: clear-cut, conversion, planting, partial harvest, low intensity fire, restoration, salvage, and herbicide. The results were validated against observed data across 8 different sites in the U.S. Southeast (Duke Forest, Joseph Jones Ecological Research Center, North Carolina Loblolly Pine, and Ordway-Swisher Biological Station) and Pacific Northwest (Metolius Research Natural Area, H.J. Andrews Experimental Forest, Wind River Field Station, and Mount Rainier National Park). These sites differ in regards to climate, vegetation, soil, and historical land disturbance as well as management approaches. Results showed that different management practices could successfully

  9. Potential Impacts of Climate Change in the Great Lakes Region

    Science.gov (United States)

    Winkler, J. A.

    2011-12-01

    Climate change is projected to have substantial impacts in the Great Lakes region of the United States. One intent of this presentation is to introduce the Great Lakes Integrated Sciences and Assessments Center (GLISA), a recently-funded NOAA RISA center. The goals and unique organizational structure of GLISA will be described along with core activities that support impact and assessment studies in the region. Additionally, observed trends in temperature, precipitation including lake effect snowfall, and lake temperatures and ice cover will be summarized for the Great Lakes region, and vulnerabilities to, and potential impacts of, climate change will be surveyed for critical natural and human systems. These include forest ecosystems, water resources, traditional and specialized agriculture, and tourism/recreation. Impacts and vulnerabilities unique to the Great Lakes region are emphasized.

  10. Study of tributary inflows in Lake Iseo with a rotating physical model

    Directory of Open Access Journals (Sweden)

    Marco Pilotti

    2014-03-01

    Full Text Available The influence of Coriolis force on the currents of large lakes is well acknowledged; very few contributions, however, investigate this aspect in medium-size lakes where its relevance could be questionable. In order to study the area of influence of the two major tributary rivers in Lake Iseo, a rotating vertically distorted physical model of the northern part of this lake was prepared and used, respecting both Froude and Rossby similarity. The model has a horizontal length scale factor of 8000 and a vertical scale factor of 500 and was used both in homogeneous and in thermally stratified conditions. We explored the pattern of water circulation in front of the entrance mouth for different hydrologic scenarios at the beginning of spring and in summer. We neglected the influence of winds. The primary purposes of the model were twofold: i to increase our level of knowledge of the hydrodynamics of Lake Iseo by verifying the occurrence of dynamical effects related to the Earth’s rotation on the plume of the two tributaries that enter the northern part of the lake and ii to identify the areas of the lake that can be directly influenced by the tributaries’ waters, in order to provide guidance on water quality monitoring in zones of relevant environmental and touristic value. The results of the physical model confirm the relevant role played by the Coriolis force in the northern part of the lake. Under ordinary flow conditions, the model shows a systematic deflection of the inflowing waters towards the western shore of the lake. The inflow triggers a clockwise gyre within the Lovere bay, to the West of the inflow, and a slow counter-clockwise gyre, to the East of the inflow, that returns water towards the river mouth along the eastern shore. For discharges with higher return period, when only the contribution by Oglio River is relevant, the effect of the Earth’s rotation weakens in the entrance zone and the plume has a more rectilinear pattern

  11. Organic sedimentation in modern lacustrine systems: A case study from Lake Malawi, East Africa

    Science.gov (United States)

    Ellis, Geoffrey S.; Barry J. Katz,; Christopher A. Scholz,; Peter K. Swart,

    2015-01-01

    This study examines the relationship between depositional environment and sedimentary organic geochemistry in Lake Malawi, East Africa, and evaluates the relative significance of the various processes that control sedimentary organic matter (OM) in lacustrine systems. Total organic carbon (TOC) concentrations in recent sediments from Lake Malawi range from 0.01 to 8.80 wt% and average 2.83 wt% for surface sediments and 2.35 wt% for shallow core sediments. Hydrogen index (HI) values as determined by Rock-Eval pyrolysis range from 0 to 756 mg HC g−1 TOC and average 205 mg HC g−1 TOC for surface sediments and 228 mg HC g−1 TOC for shallow core samples. On average, variations in primary productivity throughout the lake may account for ~33% of the TOC content in Lake Malawi sediments (as much as 1 wt% TOC), and have little or no impact on sedimentary HI values. Similarly, ~33% to 66% of the variation in TOC content in Lake Malawi sediments appears to be controlled by anoxic preservation of OM (~1–2 wt% TOC), although some component of the water depth–TOC relationship may be due to physical sediment transport processes. Furthermore, anoxic preservation has a minimal effect on HI values in Lake Malawi sediments. Dilution of OM by inorganic sediment may account for ~16% of variability in TOC content in Lake Malawi sediments (~0.5 wt% TOC). The effect of inputs of terrestrial sediment on the organic character of surface sediments in these lakes is highly variable, and appears to be more closely related to the local depositional environment than the regional flux of terrestrial OM. Total nitrogen and TOC content in surface sediments collected throughout the lake are found to be highly correlated (r2 = 0.95), indicating a well-homogenized source of OM to the lake bottom. The recurring suspension and deposition of terrestrial sediment may account for significant amounts of OM deposited in offshore regions of the lake. This process effectively separates denser

  12. An Initial Analysis of LANDSAT-4 Thematic Mapper Data for the Discrimination of Agricultural, Forested Wetlands, and Urban Land Cover. [Poinsett County, Arkansas; and Reelfoot Lake and Union City, Tennessee

    Science.gov (United States)

    Quattrochi, D. A.

    1985-01-01

    The capabilities of TM data for discriminating land covers within three particular cultural and ecological realms was assessed. The agricultural investigation in Poinsett County, Arkansas illustrates that TM data can successfully be used to discriminate a variety of crop cover types within the study area. The single-date TM classification produced results that were significantly better than those developed from multitemporal MSS data. For the Reelfoot Lake area of Tennessee TM data, processed using unsupervised signature development techniques, produced a detailed classification of forested wetlands with excellent accuracy. Even in a small city of approximately 15,000 people (Union City, Tennessee). TM data can successfully be used to spectrally distinguish specific urban classes. Furthermore, the principal components analysis evaluation of the data shows that through photointerpretation, it is possible to distinguish individual buildings and roof responses with the TM.

  13. Assessing Eutrophication Potential of a Freshwater Lake by Relating Its Bioproductivity and Biodiversity: A Case Study of Lake Wilson on Central Oahu, Hawaii

    Directory of Open Access Journals (Sweden)

    Tsu-Chuan Lee

    2018-03-01

    Full Text Available Algal bloom in a freshwater lake is a rapid increase of aquatic plants, which disrupts the ecological balance and its potential for beneficial uses. This problem has been managed by relating the trophic levels of a lake with nutrient loading. This traditional management approach is less than satisfactory as it neglects considering the intricate relationship between nutrient loading and the algal community. As a result, it often fails to detect an imminent algal bloom and fails to formulate and implement timely remedial measures. The advancement of modern molecular biosciences has provided an opportunity to improve this traditional approach. In this study, field and laboratory experiments on lake bioproductivity and biodiversity were conducted in Lake Wilson on central Oahu, Hawaii. Bioproductivity or algal productivity was evaluated in terms of the rate of chlorophyll growth in the lake water, and the biodiversity or genetic biodiversity was evaluated by using the method of denaturing gradient gel electrophoresis of the algae species and the Shannon index. Research results indicated that eukaryote communities in Lake Wilson were more diverse under the mesotrophic state of algal productivity than those under the oligotrophic and eutrophic states. Therefore, the reduction of the biodiversity of a mesotrophic lake can be used in water quality management as a warning sign of an imminent algal bloom.

  14. Null models for study Rotifers and Crustaceans Zooplankton species richness in Chilean Patagonian lakes

    OpenAIRE

    Escalante, Patricio de los Ríos

    2016-01-01

    Abstract Aims The Patagonian lakes are characterized by their oligotrophy that is the cause of low species number in their zooplankton assemblage. The aim of the present study is to analyze the crustacean and rotifers species number pattern in Patagonian lakes among a latitudinal gradient (40-51 °S). Results The results revealed that there are direct significant correlations between total species with rotifer species, and chlorophyll concentration with crustacean species number, and an inve...

  15. Source identification and mass balance studies of mercury in Lake An-dong, S. Korea

    Science.gov (United States)

    Han, J.; Byeon, M.; Yoon, J.; Park, J.; Lee, M.; Huh, I.; Na, E.; Chung, D.; Shin, S.; Kim, Y.

    2009-12-01

    In this study, mercury and methylmercury were measured in atmospheric, tributary, open-lake water column, sediment, planktons and fish samples in the catchments area of Lake An-dong, S. Korea. Lake An-dong, an artificial freshwater lake is located on the upstream of River Nak-dong. It has 51.5 km2 of open surface water and 1.33 year of hydraulic residence time. It is a source of drinking water for 0.3 million S. Koreans. Recently, the possibilities of its mercury contamination became an issue since current studies showed that the lake had much higher mercury level in sediment and certain freshwater fish species than any other lakes in S. Korea. This catchments area has the possibilities of historical mercury pollution by the location of more than 50 abandoned gold mines and Young-poong zinc smelter. The objective of this study was to develop a mercury mass balance and identify possible mercury sources in the lake. The results of this study are thus expected to offer valuable insights for the sources of mercury loading through the watershed. In order to estimate the mercury flux, TGM, RGM and particulate mercury were measured using TEKRAN 2537 at the five sites surrounding Lake An-dong from May, 2009 with wet and dry deposition. The fate and transport of mercury in water body were predicted by using EFDC (Environmental Dynamic Fluid Code) and Mercury module in WASP7 (Water quality analysis program) after subsequent distribution into water body, sediments, followed by bioaccumulation and ultimate uptake by humans. The mercury mass balance in Young-poong zinc smelter was also pre-estimated by measuring mercury content in zinc ores, emission gases, sludge, wastewater and products.

  16. Limnological characterisation and phytoplankton seasonal variation in a subtropical shallow lake (Guaiba Lake, Brazil: a long-term study

    Directory of Open Access Journals (Sweden)

    Rodrigo da Rocha Andrade

    2014-12-01

    Full Text Available AIM: to provide a long-term limnological characterisation of a subtropical shallow lake in addition to verifying seasonal differences, including phytoplankton variation. METHODS: monthly sampling at sites IP, SJ and MD from 2000 to 2009 to analyse temperature - T; depth - Z; the depth of the euphotic zone - Zeu; Zeu/Z (%; total suspended solids - TSS; dissolved oxygen - DO; pH; electrical conductivity - EC; N-NH3, N-NO2, N-NO3; soluble reactive phosphorus - SRP; chlorophyll a - Chl-a and phytoplankton. RESULTS: low values of Z and Zeu characterised the shallow and turbid conditions of lake and corresponded to the contribution of nano-microflagellates (Chlamydomonas sp., Spermatozopsis sp., Cryptomonas sp. and Rhodomonas sp and diatoms (Aulacoseira granulata. Zeu/Z (%, SRP and Chl-a were significantly different at site IP (meso-eutrophic compared to sites SJ and MD (eutrophic. Phytoplankton density was also significantly higher at sites SJ and MD, and the largest relative contribution of Actinastrum sp., Dictyosphaerium sp., Micractinium sp., Monoraphidium sp., Scenedesmus/Desmodesmus sp. and Euglena sp. corresponded to the most polluted waters at site SJ. The significantly higher T (ºC in summer corresponded to significantly higher Chl-a as well as a greater richness and density of phytoplankton. Cocconeis sp., Gomphonema sp. and Pinnularia sp. (pennated diatoms were negatively correlated with temperature and were therefore more representative at the three sites in winter. Asterionella formosa was correlated with SRP and vernal blooms were recorded (2000-2001. Planktothrix isothrix and Planktothricoides raciborskii were expressive in the summer/late summer (2004-2005, and were significantly correlated with Chl-a and low SRP in water column. CONCLUSIONS: The study corroborated the sensitivity of phytoplankton in characterising different stages of eutrophication at different sites and corresponding watersheds as well as in characterising

  17. Combining Radar and Optical Data for Forest Disturbance Studies

    Science.gov (United States)

    Ranson, K. Jon; Smith, David E. (Technical Monitor)

    2002-01-01

    Disturbance is an important factor in determining the carbon balance and succession of forests. Until the early 1990's researchers have focused on using optical or thermal sensors to detect and map forest disturbances from wild fires, logging or insect outbreaks. As part of a NASA Siberian mapping project, a study evaluated the capability of three different radar sensors (ERS, JERS and Radarsat) and an optical sensor (Landsat 7) to detect fire scars, logging and insect damage in the boreal forest. This paper describes the data sets and techniques used to evaluate the use of remote sensing to detect disturbance in central Siberian forests. Using images from each sensor individually and combined an assessment of the utility of using these sensors was developed. Transformed Divergence analysis and maximum likelihood classification revealed that Landsat data was the single best data type for this purpose. However, the combined use of the three radar and optical sensors did improve the results of discriminating these disturbances.

  18. Bioenergy harvest impacts to biodiversity and resilience vary across aspen-dominated forest ecosystems in the Lake States region, USA

    Science.gov (United States)

    Miranda T. Curzon; Anthony W. D' Amato; Brian J. Palik; Kris Verheyen

    2016-01-01

    Questions: Does the increase in disturbance associated with removing harvest residues negatively impact biodiversity and resilience in aspen-dominated forest ecosystems? How do responses of functional diversity measures relate to community recovery and standing biomass? Location: Aspen (Populus tremuloides, Michx.) mixedwood forests in Minnesota...

  19. Social perception of the forest landscape in Trentino-Alto Adige (Italy: comparison of case studies

    Directory of Open Access Journals (Sweden)

    Pastorella F

    2016-12-01

    Full Text Available The landscape is the product of human activities and nature as developed during the centuries. However, the landscape has a symbolic value because it can be considered the identity and culture of a territory that includes the values and beliefs of local population. The Alpine landscape is a unicum in the world due to its geomorphologic, climatic and vegetation characteristics and socio-economic conditions of local population. Over the centuries the social perception of Alps has changed: in a first phase the Alps were considered “horrible and scary mountains”, later Alps were perceived as “beautiful and fascinating places”, and currently the Alpine mountains are considered a place of relaxation and recreation. The analysis of landscape perception aimed to investigate the visitors’ opinions about landscape is an important instrument to support the decision concerning the land planning and management. This study focuses on the analysis of the aesthetic perception of visitors on Alpine landscapes following two perspectives: a first overall perspective considering the landscape as a mosaic of different land uses and a second perspective of detail observing the individual components that characterize the forest landscape. The aim of the study is to identify the most appreciated elements of landscape from the aesthetic point of view and the influence of socio-demographic characteristics of respondents on individual perception. In order to investigate the perception about the Alpine landscapes 358 visitors of two sites of Trentino-Alto Adige (Val di Genova and Santa Maria lake were interviewed using a structured questionnaire. The results show that the most appreciated elements of the landscape by the visitors are water (lakes and rivers and forests. These preferences are also conditioned by the site where the interviews were made. In addition, the results show that for the respondents of this survey the forest with the highest attractiveness

  20. Deforestation and Industrial Forest Patterns in Colombia: a Case Study

    Science.gov (United States)

    Huo, L. Z.; Boschetti, L.; Sparks, A. M.; Clerici, N.

    2017-12-01

    The recent peace agreement between the government and the Revolutionary Armed Forces of Colombia (FARC) offers new opportunities for peaceful and sustainable development, but at the same time requires a timely effort to protect biological resources, and ecosystem services (Clerici et al., 2016). In this context, we use the 2001-2017 Landsat data record to prototype a methodology to establish a baseline of deforestation, afforestation and industrial forest practices (i.e. establishment and harvest of forest plantations), and to monitor future changes. Two study areas, which have seen considerable deforestation in recent years, were selected: one in the South of the country, at the edge of the Amazon Forest (WRS path 008 row 059) and one in the center, in mixed forest (WRS path 008 row 055). The time series of all the available cloud free Landsat 5, Landsat 7 and Landsat 8 data was classified into a sequence of binary forest/non forest maps using a deep learning model, successfully used in the natural language processing field, trained to detect forest transitions. Recurrent Neural Networks (RNN) is a class of artificial neural network that extends the conventional neural network with loops in the connections (Graves et al., 2013). Unlike a feed-forward neural network, an RNN is able to process the sequential inputs by having a recurrent hidden state whose activation at each step depends on that of the previous steps. In this manner, the RNN provides a good framework to dynamically model time series data, and has been successfully applied to natural language processing in Google (Sutskever et al., 2014). The sequence of forest cover state maps was subsequently post-processed to differentiate between deforestation (e.g. transition from forest to non forest land use) and industrial forest harvest (i.e. timber harvest followed by regrowth), by integrating the detection of temporal patterns, and spatial patterns. References Clerici, N., et al., (2016). Colombia: Dealing

  1. Studying of Forests Potentials for Introducing of Mediterranean Industrial Woody Species to Desertification Combating

    Science.gov (United States)

    Mahdavi Najafabadi, R.; Khajeddin, S. J.; Sofyanian, A. R.; Karimzadeh, H. R.; Rezaei, M.

    2009-04-01

    Most of arid and semiarid parts of the world suffer from great lack of forest land. Therefore taking a good care of these forest lands quantity and quality and control of renewable natural resources is very important. Zagroass forests are located in semiarid parts of Iran. The main purpose of this research is to determine the potential habitat of forest olive for Chaharmahal va Bakhtiary using GIS. This province has a total area of 1653300 hectars. The main steps of this project are as follows: collecting data and maps, digitizing topographic maps with scale of 1:25000, and developing maps of slope, elevation levels, aspect, climatic classification. Regretion analysis was performed on the climatic data and the gradian equations were developed with a high R2 value. Using these equations the following maps were developed. For the whole province: isothermal, isoheytal, abs. max isothermal, relative humidity relative humidity of dry months. Soil maps were also digitized and the information system suitable for this study was developed. Using this bank the following layers were made: land units, soil depth, two soil textures, EC, pH, CaCo3. The following layers were made using digitized data, land use hydraulic network, lake and marsh land. Considering ecological needs of olive and extracting them from all diferent layers using boolean method. The layers showing suitable locations for planting olive(olea europea) was made. One of these maps includes all types of soils suitable for planting olive and the other excludes silty clay loam soils which are not so suitable. The total area achived was 9500 hectars in the whole province and the area excluding silty clay loam soils was determined to be 900 hectars. Using RS information and GIS technology in these types of projects can increase accuracy specialy including some more layers is recommended.

  2. [Estimation of DOC concentrations using CDOM absorption coefficients: a case study in Taihu Lake].

    Science.gov (United States)

    Jiang, Guang-Jia; Ma, Rong-Hua; Duan, Hong-Tao

    2012-07-01

    Dissolved organic carbon (DOC) is the largest organic carbon stock in water ecosystems, which plays an important role in the carbon cycle in water. Chromophoric dissolved organic matter (CDOM), an important water color variation, is the colored fraction of DOC and its absorption controls the instruction of light under water. The available linkage between DOC concentration and CDOM absorptions enables the determination of DOC accumulations using remote sensing reflectance or radiance in lake waters. The present study explored the multi-liner relationship between CDOM absorptions [a(g) (250) and a(g) (365)] and DOC concentrations in Taihu Lake, based on the available data in 4 cruises (201005, 201101, 201103, 201105) (totally 183 sampling sites). Meanwhile, the results were validated with the data of the experiment carried out from August 29 to September 2, 2011 in Taihu Lake (n = 27). Furthermore, a universal pattern of modeling from remote sensing was built for lake waters. The results demonstrated that this method provided more satisfying estimation of DOC concentrations in Taihu Lake. Except the data obtained in January 2011, the fitted results of which were not conductive to the winter dataset (201101) in Taihu Lake, due to the diverse sources and sinks of DOC and CDOM, the multi-liner relationship was robust for the data collected in the other three cruises (R2 = 0.64, RMSE = 14.31%, n = 164), which was validated using the 201108 sampling dataset (R2 = 0.67, RMSE = 10.58%, n = 27). In addition, the form of the statistic model is universal, to some extent, for other water areas, however, there is difference in the modeling coefficients. Further research should be focused on the parameterization using local data from different lakes, which provides effective methodology for the estimation of DOC concentrations in lakes and other water regions.

  3. Measured and modelled trends in European mountain lakes: results of fifteen years of cooperative studies

    Directory of Open Access Journals (Sweden)

    Michela ROGORA

    2004-02-01

    Full Text Available Papers included in this Special Issue of the Journal of Limnology present results of long-term ecological research on mountain lakes throughout Europe. Most of these studies were performed over the last 15 years in the framework of some EU-funded projects, namely AL:PE 1 and 2, MOLAR and EMERGE. These projects together considered a high number of remote lakes in different areas or lake districts in Europe. Central to the projects was the idea that mountain lakes, while subject to the same chemical and biological processes controlling lowland lakes, are more sensitive to any input from their surroundings and can be used as earlywarning indicators of atmospheric pollution and climate change. A first section of this special issue deal with the results of long-term monitoring programmes at selected key-sites. A second section focuse on site-specific and regional applications of an acidification model designed to reconstruct and predict long-term changes in the chemistry of mountain lakes.

  4. Surface-enhanced Raman spectroscopy studies of yellow organic dyestuffs and lake pigments in oil paint.

    Science.gov (United States)

    Mayhew, Hannah E; Fabian, David M; Svoboda, Shelley A; Wustholz, Kristin L

    2013-08-21

    Identifying natural, organic dyes and pigments is important for the conservation, preservation, and historical interpretation of works of art. Although previous SERS studies have demonstrated high sensitivity and selectivity for red lake pigments using various pretreatment conditions, corresponding investigations of yellow lake pigments and paints are relatively sparse. Here, surface-enhanced Raman scattering (SERS) spectroscopy is used to identify a variety of yellow organic dyestuffs and lake pigments in oil paint. High-quality SERS spectra of yellow dyestuffs (i.e., turmeric, old fustic, Buckthorn berries) and corresponding paints could be obtained with or without sample pretreatment using microliter quantities of HCl and methanol at room temperature. However, the SERS spectra of yellow lake pigments (i.e., Stil de Grain, Reseda lake) and their corresponding oil paints were only observed upon sample pretreatment. Ultimately, we demonstrate a reliable sample treatment protocol for SERS-based identification of turmeric, old fustic, Buckthorn berries, Stil de Grain, and Reseda lake as well as for microscopic samples of the corresponding oil paints.

  5. Vegetation changes and human settlement of Easter Island during the last millennia: a multiproxy study of the Lake Raraku sediments

    Science.gov (United States)

    Cañellas-Boltà, Núria; Rull, Valentí; Sáez, Alberto; Margalef, Olga; Bao, Roberto; Pla-Rabes, Sergi; Blaauw, Maarten; Valero-Garcés, Blas; Giralt, Santiago

    2013-07-01

    Earlier palynological studies of lake sediments from Easter Island suggest that the island underwent a recent and abrupt replacement of palm-dominated forests by grasslands, interpreted as a deforestation by indigenous people. However, the available evidence is inconclusive due to the existence of extended hiatuses and ambiguous chronological frameworks in most of the sedimentary sequences studied. This has given rise to an ongoing debate about the timing and causes of the assumed ecological degradation and cultural breakdown. Our multiproxy study of a core recovered from Lake Raraku highlights the vegetation dynamics and environmental shifts in the catchment and its surroundings during the late Holocene. The sequence contains shorter hiatuses than in previously recovered cores and provides a more continuous history of environmental changes. The results show a long, gradual and stepped landscape shift from palm-dominated forests to grasslands. This change started c. 450 BC and lasted about two thousand years. The presence of Verbena litoralis, a common weed, which is associated with human activities in the pollen record, the significant correlation between shifts in charcoal influx, and the dominant pollen types suggest human disturbance of the vegetation. Therefore, human settlement on the island occurred c. 450 BC, some 1500 years earlier than is assumed. Climate variability also exerted a major influence on environmental changes. Two sedimentary gaps in the record are interpreted as periods of droughts that could have prevented peat growth and favoured its erosion during the Medieval Climate Anomaly and the Little Ice Age, respectively. At c. AD 1200, the water table rose and the former Raraku mire turned into a shallow lake, suggesting higher precipitation/evaporation rates coeval with a cooler and wetter Pan-Pacific AD 1300 event. Pollen and diatom records show large vegetation changes due to human activities c. AD 1200. Other recent vegetation changes also

  6. Tree-Ring Investigation of an in situ Younger Dryas-Age Spruce Forest in the Great Lakes Region of N. America

    Science.gov (United States)

    Panyushkina, I. P.; Leavitt, S. W.; Lange, T.; Schneider, A. F.

    2005-12-01

    A late Pleistocene-early Holocene geological site known as Liverpool East on the southern end of Lake Michigan (in Indiana) was discovered in the early 1980s. Five previously reported radiocarbon dates on wood and peat from the deposit ranged from 9,080 to 11,290 14C yr B.P., but our subsequent radiocarbon dating of wood from in situ spruce stumps at the site has yielded four ages from 10,060 to 10,444 14C yr B.P., which correspond to calibrated calendar ages between about 11,550 and 12,500 Cal yr B.P. These dates place this forest squarely into the Younger Dryas event, and offer an unusual opportunity for exploring high-resolution environmental variability during an abrupt climate change event related to ocean thermohaline circulation. In the last 3 years, we have collected more than 130 pieces of wood from the site, about 65 of which are from stumps. Typical separation of trees was about 2-3 m, suggesting more of an open woodland than dense forest. The tilting of many stumps suggests the effect of wind on trees rooted in a soft peat substrate, and their tops broken at uniform height seem consistent with a subsequent rise in lake level, beach sand deposition, and ice floe event(s) that sheared off the upper trunks. Although these trees tend to be fairly young (typically 50-100 years old) and somewhat complacent, we developed a ring-width chronology to examine interannual variability. We are also measuring stable-oxygen and stable-carbon isotope ratios on α-cellulose in sequences of individual rings for several trees as additional environmental indicators of moisture and temperature. This collective set of tree-ring measurements and their statistics provide the basis for inferring the environment of this site, placed more precisely in time by "wiggle-matching" a sequence of 10-year radiocarbon measurements.

  7. Local wisdom in preservation of Lake Toba ecosystems (study on Toba Lake community in the Village of Silalahi I, Sub District of Silahisabungan, Dairi Regency, North Sumatera Province)

    Science.gov (United States)

    Hamdani Harahap, R.; Humaizi

    2018-03-01

    This study aims to analyze the perception of Batak Toba community in Silalahi I Village, Silahisabungan Subdistrict to the existence of Lake Toba, local wisdom owned by Batak Toba community in Silalahi I Village, Silahisabungan Sub District in order to preserve Lake Toba and recommend policy to revitalize it which is still running, which runs partially or which has not been done at all. The type of research used in this research is descriptive research with qualitative analysis. Data collection was conducted by interviews with key informants and informants i.e. community leaders, religious leaders and customary leaders in the study sites. The results showed that the perception of the Silalahi I Village community of Silahiabungan subdistrict to the existence of Lake Toba is a source of life. That means Lake Toba is a source of sustenance, a source of livelihood such as a place to fish, where to put floating net cages and as a sustenance of tourism activities. The form of local wisdom in preserving the area of Lake Toba is the existence of some sacred places such as Nauli basa, Partonunan stone (Deang Namora), that the entire area of Lake Toba called Tao Silalahi controlled by aunty (Namboru) Deang Namora is a purified area so prohibited spit, wearing jewelry, doing immoral, bathing over 6 o’clock, bringing and eating pork or dogs, bathing naked in the lake, laughing until laughing, and for women if there is a long hair should tie and If you want to take a bath must first permit the grandmother (oppung) guard lake. All local wisdom is still done because they still believe, although there is also rarely done. An effective way to revitalize the existing wisdom locals is to continue to perform the ritual or ceremony of the Statue of Silahisabungan once a year, and continue to obey the advice given by the King of Silahisabungan called Poda sagu-sagu marlangan.

  8. The Last Glacial cycle in SW Balkans: an interdisciplinary study at Lake Prespa

    Science.gov (United States)

    Panagiotopoulos, K.; Boehm, A.; Schaebitz, F.; Wagner, B.

    2012-12-01

    The transboundary Lake Prespa (AL/FYROM/GR) has been recognized as a conservation priority wetland. The catchment area has a remarkably diverse flora that points to its refugial properties. Lake sediments retrieved from a distal core location were investigated using sedimentological, geochemical, physical, palynological and stable isotope analyses. Based on tephrochronology, radiocarbon and ESR dating, the age model suggests that the basal part of core Co1215 reaches back to 92 ka cal BP. Here we present the response of this mid-altitude site (849 m a.s.l.) to climate oscillations during this interval and assess its sensitivity to millennial-scale variability. Periods of pronounced phytoplankton blooms (inferred from green algae and dinoflagellate concentrations) suggest that the trophic state and lake levels underwent substantial fluctuations. Calcite precipitation occurred in MIS 5 and MIS 1 and was synchronous to periods of increased primary production (terrestrial and/or lacustrine), while siderite peaks were confined to the glacial. Forest dynamics, cover and density are discussed in an altitudinal context and the existence of temperate tree refugia is examined. This project is part of the Collaborative Research Center 806: "Our way to Europe; Culture-Environment Interaction and Human Mobility in the Late Quaternary".

  9. Water ecological carrying capacity of urban lakes in the context of rapid urbanization: A case study of East Lake in Wuhan

    Science.gov (United States)

    Ding, Lei; Chen, Kun-lun; Cheng, Sheng-gao; Wang, Xu

    With the excessive development of social economy, water scarcity and water environment deterioration become a common phenomenon in metropolis. As a crucial component of urban water environment system, urban lake is mainly influenced by social economic system and tourism system. In this paper, a framework for quantitatively evaluating development sustainability of urban lake was established by a multi-objective model that represented water ecological carrying capacity (WECC). And nine key indicators including population, irrigation area, tourist quantity, the average number of hotel daily reception, TP, TN, CODMn, BOD5 were chosen from urban social-economy system and natural resilience aspects, with their index weight was determined by using the Structure Entropy Weight method. Then, we took Wuhan East Lake, the largest urban lake in China as a case study, and selected five time sections including 2002, 2004, 2007, 2009 and 2012 to synthetically evaluate and comparatively analyze the dynamic change of WECC. The results showed that: firstly, the water ecological carrying capacity values of the East Lake in five time sections were 1.17, 1.07, 1.64, 1.53 and 2.01 respectively, which all exceeded 1 and increased fluctuation. The rapid growth of population and GDP lead to sharply increasing demand for water quantity. However, a large amount of the domestic sewage and industrial waste led by economic development increases pressure on ecological environment of urban lakes. Secondly, the carrying capacity of the East Lake for tourist activities was still low. The value in 2012 was only 0.22, keeping at a slowly increasing phase, which indicates that the East Lake has large opportunity and space for developing the water resource carrying capacity and could make further efforts to attract tourists. Moreover, the WECC of the East Lake was mainly affected by rapid social and economic development and water environment damage caused by organic pollutants. From the view of urban

  10. Executive summary. Conceptual studies nuclear energy center Lake Hartwell, S.C., Phase III

    International Nuclear Information System (INIS)

    1981-01-01

    This document summarizes a conceptual study on the feasibility and practicality of developing a nuclear energy center (NEC) at a specific site in the SSEB region. The site selected for this conceptual study is at Lake Hartwell, South Carolina. The conceptual NEC at Lake Hartwell consists of twelve 1250-MW(e) LWRs arranged on the site in four cluster of three units each, know as triads. The nominal distance between triads was selected as 2-1/2 miles. The total electric output of 15,000 MWe to be generated by the NEC would be transmitted to five major utilities in South Carolina, North Carolina, and Georgia. Objective of the study was to assess the technical, socioeconomic, environmental, and institutional issues relating to the NEC at the conceptual study site. The basic finding was that the concept of a NEC on the Lake Hartwell site is feasible, but further analysis of institutional issues and possible legislation would be required

  11. A new morphometric study of Carioca Lake, Parque Estadual do Rio Doce (PERD, Minas Gerais State, Brazil - DOI: 10.4025/actascibiolsci.v32i1.4990

    Directory of Open Access Journals (Sweden)

    Ricardo Motta Pinto-Coelho

    2009-12-01

    Full Text Available Carioca Lake is located within the limits of the Rio Doce State Park, in the eastern part of the state of Minas Gerais. This park, one of the largest natural reserves of the Atlantic Rain Forest in Brazil, is a hotspot of tropical biodiversity. The purpose of this study was to update existing information on the bathymetry and morphometric features of the lake, using differential GPS (DGPS technology for data collection, coupled to a digital echo sounder. The bathymetry was based on the acquisition of 1106 points, where the depths as well as the geographic coordinates were obtained. The new study allowed the refinement of existing primary and secondary morphometric data for this lake.

  12. The intertwining paths of the density managment and riparian buffer study and the Northwest Forest Plan

    Science.gov (United States)

    Kenneth J. Ruzicka; Deanna H. Olson; Klaus J. Puettmann

    2013-01-01

    Initiated simultaneously, the Density Management and Riparian Buff er Study of western Oregon and the Northwest Forest Plan have had intertwining paths related to federal forest management and policy changes in the Pacifi c Northwest over the last 15 to 20 years. We briefl y discuss the development of the Northwest Forest Plan and how it changed the way forest policy...

  13. Fractal analysis for studying the evolution of forests

    International Nuclear Information System (INIS)

    Andronache, Ion C.; Ahammer, Helmut; Jelinek, Herbert F.; Peptenatu, Daniel; Ciobotaru, Ana-M.; Draghici, Cristian C.; Pintilii, Radu D.; Simion, Adrian G.

    2016-01-01

    Highlights: • Legal and illegal deforestation is investigated by fractal analysis. • A new fractal fragmentation index FFI is proposed. • Differences in shapes of forest areas indicate the type of deforestation. • Support of ecological management. - Abstract: Deforestation is an important phenomenon that may create major imbalances in ecosystems. In this study we propose a new mathematical analysis of the forest area dynamic, enabling qualitative as well as quantitative statements and results. Fractal dimensions of the area and the perimeter of a forest were determined using digital images. The difference between fractal dimensions of the area and the perimeter images turned out to be a crucial quantitative parameter. Accordingly, we propose a new fractal fragmentation index, FFI, which is based on this difference and which highlights the degree of compaction or non-compaction of the forest area in order to interpret geographic features. Particularly, this method was applied to forests, where large areas have been legally or illegally deforested. However, these methods can easily be used for other ecological or geographical investigations based on digital images, including deforestation of rainforests.

  14. Geo-spatial analysis of land use and land cover changes in the Lake ...

    African Journals Online (AJOL)

    This paper examines forest degradation and biodiversity loss in the Lake Bosomtwe Basin of Ghana between 1986 and 2008 from a geospatial perspective. The study was conducted using an integrated approach with Remote Sensing and GIS techniques, and supported with socioeconomic data for forest cover change ...

  15. Limnological study of Shasta Lake, Shasta County, California, with emphasis on the effects of the 1977 drought

    Science.gov (United States)

    Rettig, S.A.; Bortleson, Gilbert C.

    1983-01-01

    An intensive limnological study of Shasta Lake was made in conjunction with the California Department of Water Resources during the 1977 drought. Water-quality data were collected from March 1977 through September 1978 at six lake stations and four lake tributary stations. Data collected during and after the drought were compared. Lake water quality is described as a function of lake morphometry, climate, hydrology, and reservoir hydraulics. Results indicate Shasta Lake is a warm monomictic lake. Tributary inflow to the lake and outflow through the dam generate density currents which promote mixing at depth and the development of an extensive metalimnion. During the drought, record low lake levels resulted in the exposure of an extensive nearshore sediment zone. Resuspended sediments caused a deterioration of water quality. The most notable effects, in comparison with post-drought conditions, were decreased light penetration, increased dissolved-solids concentration and specific conductance, decreased dissolved-oxygen concentrations, and elevated nutrient levels. A hypolimnetic anoxic condition was observed at the upstream stations of the lake. (USGS)

  16. Floristic diversity of midforest lakes (Sobibór Landscape Park, Poland

    Directory of Open Access Journals (Sweden)

    Sender Joanna

    2016-12-01

    Full Text Available Aquatic vegetation greatly impacts lake functions. Forest ecosystems surrounding lakes are effective protection zone of lakes and their associated flora and fauna. The presence of aquatic plants depends on many factors, including the chemical composition and acidity of water, the shape of the lake catchment, the angle of slope along shorelines and the management of surrounding lands. Natural ecosystems throughout Eastern Europe are threatened by anthropogenic activities. Aquatic systems and bogs are particularly sensitive to disturbances. The aim of the study was to determine the influence of land management, forest type and stand age on aquatic plant colonisation within lakes as well as to quantify and qualify the structure of macrophyte communities within two lakes, Płotycze Sobiborskie and Orchowe, located in the Sobibór Landscape Park in western Poland. Even though there were few bogs within the catchment areas and lake buffer zones, where they did occur they had the greatest effect on macrophyte presence. The results of this research indicate that in the absence of anthropogenic disturbances midforest water-bog complexes are relatively stable systems and preserve their natural character. The applied multi-criteria evaluation of macrophytes in the studied lakes and their surrounding buffer zones and catchment areas allowed the lakes to be characterised as lakes with a good ecological status.

  17. Phytoplankton community of Lake Baskandi anua, Cachar District, Assam, North East India – An ecological study

    Directory of Open Access Journals (Sweden)

    Devi M.B.

    2016-01-01

    Full Text Available Diversity, relative abundance and dominance of phytoplankton community of the Lake Baskandi anua, an oxbow lake of Assam, North east India were studied during December 2009 to November 2010. Chlorophyll content and biomass of phytoplankton along with physico-chemical properties of water of the lake were also estimated. The lake is covered with Hydrilla and other macrophytes like Eichhornia, Trapa, Altrnenthera, Polygonum, Ludwizia sp., etc. Seasonal fluctuations of 41 genera of phytoplankton, belonging to 5 groups (Chlorophyceae, Cyanobacteria, Bacillariophyceae, Euglenophyceae and Dinophyceae were encountered in the lake. Chlorophyceae was found to be highest in winter, Cyanobacteria and Euglena in monsoon and Bacillariophyceae in pre monsoon. According to Engelmann’s scale, Spirogyra indica was found eudominant followed by 10 dominant, 24 subdominant and 20 recedent species. Chlorophyll- a content of phytoplankton varied from 14.18 to 33.89 μg·L-1, during the study period. One way analysis of variance (ANOVA revealed significant seasonal variation in physico-chemical properties of water like Water temperature, pH, Conductivity, Dissolved oxygen, Free CO2, Total alkalinity, Calcium, Chloride, Nitrate and Ammonia. Relationship between phytoplankton group assemblage and environmental variables were explored by the ordination method CCA (Canonical Correspondence Analysis.

  18. A study of autotrophic communities in two Victoria Land lakes (Continental Antarctica using photosynthetic pigments

    Directory of Open Access Journals (Sweden)

    Roberto BARGAGLI

    2010-08-01

    Full Text Available The composition of algal pigments and extracellular polymeric substances (EPS was determined in microbial mats from two lakes in Victoria Land (Continental Antarctica with different lithology and environmental features. The aim was to expand knowledge of benthic autotrophic communities in Antarctic lacustrine ecosystems, providing reference data for future assessment of possible changes in environmental conditions and freshwater communities. The results of chemical analyses were supported by microscopy observations. Pigment profiles showed that filamentous cyanobacteria are dominant in both lakes. Samples from the water body at Edmonson Point had greater biodiversity, fewer pigments and lower EPS ratios than those from the lake at Kar Plateau. Differences in mat composition and in pigment and EPS profile between the two lakes are discussed in terms of local environmental conditions such as lithology, ice-cover and UV radiation. The present study suggests that a chemical approach could be useful in the study of benthic communities in Antarctic lakes and their variations in space and time.

  19. PILOT STUDIES WITH A PHOTOGRAMMETRIC GLACIER LAKE OUTBURST FLOOD EARLY WARNING SYSTEM

    Directory of Open Access Journals (Sweden)

    H. G. Maas

    2012-07-01

    Full Text Available Glacier Lake Outburst Floods (GLOFs depict an environmental risk with an increasing damage potential in many regions of the world. GLOFs are often caused by glacier margin lakes, which suddenly find a drainage path underneath the bottom of a glacier, which is destabilized and retreating as a consequence of local or global climate changes. In a typical GLOF event, a glacier margin lake may drain completely in 24 hours, causing a large flood wave in the area downstream the glacier. The paper documents some recent GLOF events in the Northern Patagonian Icefield (Chile and presents a terrestrial photogrammetric glacier margin lake monitoring system. The system is based on a camera taking images at regular time intervals. In these images, variations of the water level can be detected by tracking the water-land interface at pre-defined image spots. Due to the drainage mechanism, which is characterized by progressive erosion and melting at the bottom of the glacier, GLOFs are indicated by a progressive water level drop in the lake. Water level changes may be detected with subpixel accuracy by image sequence processing methods. If a 3D model of the lake bottom topography (or at least one height profile through the lake exists, water level changes in monoscopic image sequences may be transformed into volume loss. The basic idea herein is the intersection of a terrain profile with a water level detected in the image and projected into object space. The camera orientation is determined through a GPS-supported photogrammetric network. Camera orientation changes, which may for instance be induced by wind, can be compensated by tracking some fiducial marks in the image. The system has been used in a pilot study at two glacier margin lakes in the Northern Patagonian Icefield. These lakes have a depth of about 80 - 100 meters. The larger one has a length of 5 km and a maximum volume of about 200,000,000 cubic meters. During the pilot study, several GLOF events

  20. Final report. Conceptual studies nuclear energy center Lake Hartwell, S.C., Phase III

    International Nuclear Information System (INIS)

    1981-01-01

    This document summarizes a conceptual study on the feasibility and practicality of developing a nuclear energy center (NEC) at a specific site in the SSEB region. The site selected for this conceptual study is at Lake Hartwell, South Carolina. The conceptual NEC at Lake Hartwell consists of twelve nuclear electric generating units, arranged on the site in four clusters of three units each, known as triads. The nominal distance between triads was selected as 2-1/2 miles. Each unit was assumed to be a 1250 MW(e). The total electric output of 15,000 MWe would be transmitted to five major utilities in South Carolina, North Carolina, and Georgia. The basic finding was that the concept of a NEC on the Lake Hartwell site is feasible, but further analysis of institutional issues and possible legislation would be required

  1. An Integrated Approach for Understanding Anthropogenic and Climatic Impacts on Lakes: A Case study from Lake Iznik, Turkey

    Science.gov (United States)

    Derin, Y.; Milewski, A.; Fryar, A. E.; Schroeder, P.

    2013-12-01

    Lakes are among the most vital natural water resource, providing many environmental and economic advantages to a region. Unfortunately, many lakes are disappearing or continue to be polluted as industrial and agricultural practices increase to keep pace with rising populations. Lake Iznik, the biggest lake (approximately 300 km2) in the Marmara Region in Turkey, is a significant water resource as it provides opportunities for recreational activities, agriculture, industry, and water production for the region. However, rapid population growth combined with poor land management practices in this water basin has contributed to decreased water quality and water levels. As a result, Lake Iznik has switched from being Mesotrophic to Eutrophic in the past thirty years. This research aims to understand both the anthropogenic and climatic impacts on Lake Iznik. An integrated approach combining satellite remote sensing, hydrogeology, hydrologic modeling, and climatology was utilized to identify the source and timing responsible for the decline in water quality and quantity. Specifically, Landsat TM images from 1990, 2000, 2005, and 2010 were collected, processed, and analyzed for changes in landuse/landcover and surface area extent of Lake Iznik. Water level and water quality data (e.g. streamflow, lake level, pH, conductivity, total nitrogen, total dissolved solid etc.) collected from the General Directorate of State Hydraulic Works (DSI) from 1980-2012 were obtained from 4 stations and compared to the Landsat landuse mosaics. Meteorological data collected from Turkish State Meteorological Service from 1983-2012 were obtained from 3 stations (precipitation, temperature, atmospheric pressure, relative humidity, vapor pressure, wind speed and pan evaporation). A hydrologic model using MIKE21 was constructed to measure the change in streamflow and subsequent lake level as a result of changes in both land use and climate. Results have demonstrated the drop in water level from

  2. Studies of the Woody Vegetation of the Welor Forest Reserve ...

    African Journals Online (AJOL)

    komla

    West African Journal of Applied Ecology - Volume 13. Studies of the Woody Vegetation of the Welor Forest Reserve. (Senegal) for Sustainable Use. B. Sambou*, A. T. Bâ, C. Mbow and A. Goudiaby. Institute of Environmental Sciences, Faculty of Sciences and Techniques,. University Cheikh Anta Diop, Dakar-Fann, BP 5005, ...

  3. Logging activities in mangrove forests: A case study of Douala ...

    African Journals Online (AJOL)

    Logging activities in mangrove forests: A case study of Douala Cameroon. N Din, P Saenger, P.R. Jules, D.D. Siegfried, F Basco. Abstract. The Cameroon mangroves are exploited by local communities through fishing, hunting, and especially logging for fuel-wood and charcoal. The changing demographic patterns in the ...

  4. Avian studies and research opportunities in the Luquillo Experimental Forest: a tropical rain forest in Puerto Rico

    Science.gov (United States)

    Joseph Wunderle, Jr; Wayne J. Arendt

    2011-01-01

    The Luquillo Experimental Forest (LEF) located on the Caribbean island of Puerto Rico has a rich history of ecological research, including a variety of avian studies, and is one of the most active ecological research sites in the Neotropics. The LEF spans an elevational range from 100 to 1075mover which five life zones and four forest types are found in a warm, humid...

  5. Climate Change Assessments for Lakes Region of Turkey

    Directory of Open Access Journals (Sweden)

    Ayten Erol

    2012-07-01

    Full Text Available Climate change is one of the most important challenges for forestry. Forests are known to be most efficient natural tools to ensure availability and quality of water in many regions. Besides, planning of forest resources towards water quality and quantity is essential in countries that are expected to face with more frequent drought periods in the next decades due to climate change. Watershed management concept has been supposed as the primary tool to plan natural resources in a more efficient and sustainable way by both academicians and practitioners to mitigate and adapt climate change. Forest cover among other land use types provides the best regulating mechanism to mitigate erosion, sedimentation, desertification, and pollution. In addition, climate change can potentially affect forest stand dynamics by influencing the availability of water resources. Therefore, the amount of forest cover in a watershed is an indicator of climate change mitigation and adaptation. Climate change is a concern and risk for the sustainability of water resources in Lakes Region of Turkey. The objective of this study is to make a comprehensive assessment in lake watersheds of the Lakes region considering the forest cover. For this purpose, the study gives a general view of trends in climatic parameters using Mann Kendall trend test. The results showed that Mann Kendall trend test for temperature and precipitation data is not enough to evaluate the magnitude of potential changes of climate in terms of forest cover. Understanding impacts of changes in temperature and precipitation on forest cover, runoff data should be evaluated with temperature and precipitation for watersheds of forest areas in Lakes Region.

  6. Disturbance history of the Medicine Bow Range, Wyoming, using historical documents, contemporary forest inventory, and lake sediment cores

    Science.gov (United States)

    V. Carter; A. Brunelle; J. Shaw

    2014-01-01

    In the late 1860s, Euro-American settlement and related activities, including logging, began affecting the composition and structure of forests of the western United States. These impacts were likely to be most substantial along the corridor of the trans-continental railroad. Construction and maintenance of the railroad created a high dependence for wood, especially...

  7. Wisconsin's Lake Superior Basin Water Quality Study. Technical Report No. 1.

    Science.gov (United States)

    Dickas, Albert B., Ed.

    This hydrologic study focuses on Wisconsin's Lake Superior Basin. Water is the most important natural resource in this area which includes Douglass, Bayfield, Ashland, and Iron counties. This study was undertaken to determine the character of this hydrologic base and to determine the effects and extent of man-influenced disturbances. It includes…

  8. Rapid changes in the level of Kluane Lake in Yukon Territory over the last millennium

    Science.gov (United States)

    Clague, John J.; Luckman, Brian H.; Van Dorp, Richard D.; Gilbert, Robert; Froese, Duane; Jensen, Britta J. L.; Reyes, Alberto V.

    2006-09-01

    The level of Kluane Lake, the largest lake in Yukon Territory, was lower than at present during most of the Holocene. The lake rose rapidly in the late seventeenth century to a level 12 m above present, drowning forest and stranding driftwood on a conspicuous high-stand beach, remnants of which are preserved at the south end of the lake. Kluane Lake fell back to near its present level by the end of the eighteenth century and has fluctuated within a range of about 3 m over the last 50 yr. The primary control on historic fluctuations in lake level is the discharge of Slims River, the largest source of water to the lake. We use tree ring and radiocarbon ages, stratigraphy and sub-bottom acoustic data to evaluate two explanations for the dramatic changes in the level of Kluane Lake. Our data support the hypothesis of Hugh Bostock, who suggested in 1969 that the maximum Little Ice Age advance of Kaskawulsh Glacier deposited large amounts of sediment in the Slims River valley and established the present course of Slims River into Kluane Lake. Bostock argued that these events caused the lake to rise and eventually overflow to the north. The overflowing waters incised the Duke River fan at the north end of Kluane Lake and lowered the lake to its present level. This study highlights the potentially dramatic impacts of climate change on regional hydrology during the Little Ice Age in glacierised mountains.

  9. Assessing double counting of carbon emissions between forest land cover change and forest wildfires: a case study in the United States, 1992-2006

    Science.gov (United States)

    Daolan Zheng; Linda S. Heath; Mark J. Ducey; Brad. Quayle

    2013-01-01

    The relative contributions of double counting of carbon emissions between forest-to-nonforest cover change (FNCC) and forest wildfires are an unknown in estimating net forest carbon exchanges at large scales. This study employed land-cover change maps and forest fire data in the four representative states (Arkansas, California, Minnesota, and Washington) of the US for...

  10. Detroit Lakes energy systems study: Phase I feasibility. Final report, February 1, 1978--July 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-07-31

    The objective of the Detroit Lakes Energy Systems Study is to determine the economic feasibility of alternative renewable energy system configurations in the northern latitudes. A forecast through both 1990 and the year 2000 is made of the demand for electrical energy in the Detroit Lakes area. An assessment of renewable energy resources including biomass, wind, and insolation is provided. A detailed analysis is made of system costs including biomass, wind, solar thermal, solar photovoltaic, selected hybrids, and conventional fuel systems. Lessons learned and recommendations for prototype fabrication are highlighted. (MHR)

  11. Study of the Microbial Diversity of a Newly Discovered East Antarctic Freshwater Lake, L27C, and of a Perennially Ice-Covered Lake Untersee

    Science.gov (United States)

    Huang, Jonathan P.; Hoover, Richard B.; Andersen, Dale; Bej, Asim K.

    2010-01-01

    The microbial communities that reside within freshwater lakes of Schirmacher and Untersee Oases in East Antarctica must cope with extreme conditions that may include cold temperature, annual freeze-thaw cycles, exposure to UV radiation, especially during the austral summer months, low light beneath thick ice-cover, followed by seasonal darkness. The objective of this study was to assess the microbial biodiversity and distribution from samples taken from two freshwater lakes (L27C and Lake Untersee) that were collected during the Tawani 2008 International Antarctic Expedition that conducted research in this region of Antarctica. L27C is a small, previously unreported lake residing 2 km WNW of Maitri Station at Schirmacher Oasis. Biodiversity and distribution of microorganisms within the lake were studied using both culture-independent and culture-dependent methodologies based upon the analysis of eubacterial 16S rRNA gene sequences. Lake Untersee, a perennially ice-covered, ultra-oligotrophic, lake in the Otto-von-Gruber-Gebirge (Gruber Mountains) of central Dronning Maud Land was also sampled and the microbial diversity was analyzed by eubacterial 16S rRNA gene sequences derived from pure cultures. Direct culturing of water samples from each lake on separate R2A growth medium exhibited a variety of microorganisms including: Janthinobacterium, Hymenobacter, Sphingamonas, Subtercola, Deinococcus, Arthrobacter, Flavobacterium, Polaromonas, Rhodoferax and Duganella. The evaluation of samples from L27C through culture-independent methodology identified a rich microbial diversity consisting of six different phyla of bacteria. The culture-independent analysis also displayed the majority of bacteria (56%) belonged to the Class gamma-proteobacteria within the phylum Proteobacteria. Within the Class gamma-proteobacteria, Acinetobacter dominated (48%) the total microbial load. Overall, L27C exhibited 7 different phyla of bacteria and 20 different genera. Statistical analysis

  12. Environmental effect studies on a forest ecosystem in Germany

    International Nuclear Information System (INIS)

    Yamamoto, Masayoshi; Bunzl, K.

    1993-01-01

    Long-term acid deposition on a forest ecosystem can have serious impacts on many physicochemical processes in the soil. Since 1984 extensive studies have been carried out in the 'Hoglwald', an old Norway spruce stand near Munich, Germany. In 1986 a variety of radionuclides were deposited in the canopy and on the forest floor of the Hoglwald following the reactor accident at Chernobyl. The amount of 137 Cs from Chernobyl was about 10 times larger than that present in the soil before Chernobyl. Six experimental plots were established in order to study the potential disturbances caused by artificial acid irrigation and compensative liming. Using these fields, investigations on the interception and retention of radionuclides by a coniferous woodland have been done together with the deposition and vertical migration of the radionuclides in the forest. One of the most important results obtained was that 134 Cs deposition velocity in the spruce stand was as high as 5.5 mm/s, and thus higher by a factor of 10 than the corresponding value for the grassland. By evaluating the depth profiles of the Chernobyl-derived 137 Cs in the soil with a compartment model. The fixation of radiocesium in the forest soil was found to be a rather slow process. (author)

  13. Aquatic insects of the Bohemian Forest glacial lakes: Diversity, long-term changes, and influence of acidification

    Czech Academy of Sciences Publication Activity Database

    Soldán, Tomáš; Bojková, J.; Vrba, Jaroslav; Bitušík, P.; Chvojka, P.; Papáček, M.; Peltanová, Jana; Sychra, J.; Tátosová, J.

    2012-01-01

    Roč. 18, č. 3 (2012), s. 123-283 ISSN 1211-7420 R&D Projects: GA ČR GA206/07/1200; GA ČR GA526/09/0567; GA ČR GAP505/10/0096; GA ČR GAP504/12/1218 Grant - others:GA JU(CZ) 143/2010/P; Ministerstvo kultury(CZ) DKRVO 00023272; EC project Eurolimpacs(CZ) GO-CE-CT-2003-505540; GA ČR(CZ) GPP505/10/P302 Program:GP Institutional support: RVO:60077344 Keywords : lake classification * littoral * stream Subject RIV: EH - Ecology, Behaviour

  14. 76 FR 1665 - Stakeholder Meetings Regarding the U.S.-Flag Great Lakes Fleet Revitalization Study; Correction

    Science.gov (United States)

    2011-01-11

    ... DEPARTMENT OF TRANSPORTATION Maritime Administration [Docket No. MARAD-2010-0111] Stakeholder Meetings Regarding the U.S.-Flag Great Lakes Fleet Revitalization Study; Correction AGENCY: Maritime... Lakes Fleet Revitalization Study. MARAD inadvertently listed the incorrect time zone for the listening...

  15. Coeur d'Alene Lake, Idaho: Insights Gained From Limnological Studies of 1991-92 and 2004-06

    Science.gov (United States)

    Wood, Molly S.; Beckwith, Michael A.

    2008-01-01

    More than 100 years of mining and processing of metal-rich ores in northern Idaho's Coeur d'Alene River basin have resulted in widespread metal contamination of the basin's soil, sediment, water, and biota, including Coeur d'Alene Lake. Previous studies reported that about 85 percent of the bottom of Coeur d'Alene Lake is substantially enriched in antimony, arsenic, cadmium, copper, lead, mercury, silver, and zinc. Nutrients in the lake also are a major concern because they can change the lake's trophic status - or level of biological productivity - which could result in secondary releases of metals from contaminated lakebed sediments. This report presents insights into the limnological functioning of Coeur d'Alene Lake based on information gathered during two large-scale limnological studies conducted during calendar years 1991-92 and water years 2004-06. Both limnological studies reported that longitudinal gradients exist from north to south for decreasing water column transparency, loss of dissolved oxygen, and increasing total phosphorus concentrations. Gradients also exist for total lead, total zinc, and hypolimnetic dissolved oxygen concentrations, ranging from high concentrations in the central part of the lake to lower concentrations at the northern and southern ends of the lake. In the southern end of the lake, seasonal anoxia serves as a mechanism to release dissolved constituents such as phosphorus, nitrogen, iron, and manganese from lakebed sediments and from detrital material within the water column. Nonparametric statistical hypothesis tests at a significance level of a=0.05 were used to compare analyte concentrations among stations, between lake zones, and between study periods. The highest dissolved oxygen concentrations were measured in winter in association with minimum water temperatures, and the lowest concentrations were measured in the Coeur d'Alene Lake hypolimnion during late summer or autumn as prolonged thermal stratification restricted

  16. Land Use Affects Carbon Sources to the Pelagic Food Web in a Small Boreal Lake.

    Directory of Open Access Journals (Sweden)

    Päivi Rinta

    Full Text Available Small humic forest lakes often have high contributions of methane-derived carbon in their food webs but little is known about the temporal stability of this carbon pathway and how it responds to environmental changes on longer time scales. We reconstructed past variations in the contribution of methanogenic carbon in the pelagic food web of a small boreal lake in Finland by analyzing the stable carbon isotopic composition (δ13C values of chitinous fossils of planktivorous invertebrates in sediments from the lake. The δ13C values of zooplankton remains show several marked shifts (approx. 10 ‰, consistent with changes in the proportional contribution of carbon from methane-oxidizing bacteria in zooplankton diets. The results indicate that the lake only recently (1950s obtained its present state with a high contribution of methanogenic carbon to the pelagic food web. A comparison with historical and palaeobotanical evidence indicates that this most recent shift coincided with agricultural land-use changes and forestation of the lake catchment and implies that earlier shifts may also have been related to changes in forest and land use. Our study demonstrates the sensitivity of the carbon cycle in small forest lakes to external forcing and that the effects of past changes in local land use on lacustrine carbon cycling have to be taken into account when defining environmental and ecological reference conditions in boreal headwater lakes.

  17. ENVIRONMENT PROTECTION AND ENVIRONMENT MONITORING ISSUES IN THE PROJECTS OF SUBGLACIAL LAKES STUDIES IN ANTARCTICA

    Directory of Open Access Journals (Sweden)

    I. A. Alekhina

    2012-01-01

    Full Text Available Antarctic subglacial lakes can represent extreme natural habitats for microorganisms from the position of their evolution and adaptation, as well as they can contain the information on Antarctic ice sheet history and climatic changes in their sediments. Now only direct measurements and sampling from these habitats can answer on many fundamental questions. Special precaution should be complied at penetration into these unique relic environments without unfavorable impacts and contamination. A number of recommendations were developed on levels of cleanliness and sterility during direct exploration and research of subglacial environments. Documents considered in the article are the first and necessary steps for appropriate and long-term ecological management of subglacial Antarctic environments. Today there are three projects of subglacial aquatic environment research which are in preparation and realization – the Russian project of Lake Vostok, the similar British project of Lake Ellsworth and the American project on Whillans Ice Stream. The programs of ecological stewardship for direct exploration of these lakes are discussed. All these subglacial aquatic objects of further exploration and research are so various on their structure, age and regime, that only results of all programs as a whole can help to draw us a uniform picture of a subglacial ecological system. Ecological stewardship of these should provide the minimal ecological impact with maximal scientific results. On the basis of existing documents and recommendations the general approaches and the program of ecological stewardship for Lake Vostok research are discussed. Study of drilling fluid, drilling chips, Vostok ice core and the fresh frozen water will allow to make an assessment of biological and chemical contamination as a result of the first penetration and to modify the further stewardship program for the second penetration and direct exploration of lake water.

  18. A Synthesis of Sierran Forest Biomass Management Studies and Potential Effects on Water Quality

    Directory of Open Access Journals (Sweden)

    Peter J. Weisberg

    2010-09-01

    Full Text Available The Lake Tahoe basin, located along the California and Nevada border between the Carson and Sierra Nevada mountain ranges, represents a complex forested ecosystem consisting of numerous sub-watersheds and tributaries that discharge directly to Lake Tahoe. This synthesis focuses on historical and current nutrient pools and the effects of biomass management in watersheds of the basin relative to their potential impacts on nutrient (N, P related discharge water quality. An accumulating forest floor as a result of fire suppression has resulted in the build-up of large nutrient pools that now provide a “natural” source of long term nutrient availability to surface waters. As a consequence, stand and forest floor replacing wildfire may cause a large magnitude nutrient mobilization impact on runoff water quality. Hence, mechanical harvest and controlled burning have become popular management strategies. The most ecologically significant long-term effects of controlled fire appear to be the loss of C and N from the forest floor. Although the application of controlled fire may have some initial impact on overland/litter interflow nutrient loading, controlled burning in conjunction with mechanical harvest has the potential to improve runoff water quality by reducing N and P discharge and improving the overall health of forest ecosystems without the danger of a high intensity wildfire.

  19. Mobility of 137Cs in freshwater lakes: A mass balance and diffusion study of Lake St. Clair, Southeast Michigan, USA

    Science.gov (United States)

    Wang, Jinlong; Baskaran, Mark; Niedermiller, John

    2017-12-01

    Cesium-137 is one of the most widely utilized anthropogenic radionuclides, both as a tracer and chronometer in the environment. Its application as an effective chronometer requires a thorough understanding of its geochemical behavior in aqueous systems. In this study, we collected and analyzed a suite of time-series water samples over a period of 8 months (April - November 2015), for particulate and dissolved 137Cs activities from a watershed in southeast Michigan, USA, using Cu2Fe(CN)6-coated cartridges developed to pre-concentrate dissolved 137Cs. We also conducted a series of laboratory experiments with the natural freshwater sediment samples and water with different chemical composition. There were seasonal variations of both particulate and dissolved 137Cs activities in the watersheds of Lake St. Clair. The distribution coefficients of 137Cs determined over a period of 8 months varied between 0.14 × 105 and 6.1 × 105 mL g-1 (mean: 2.9 × 105 mL g-1). The annual input and export flux of total 137Cs activity via rivers into and out of Lake St. Clair were calculated to be 3.6 × 1010 Bq and 1.6 × 1010 Bq, respectively. The amount of 137Cs derived by diffusion from interstitial pore water to the water column was estimated to be 0.30 × 1010 Bq (8.3% of the total input flux) which is similar to the percentage of 137Cs desorption (13%-20%) from sediment placed in oxic soft water system over a period of 30-106 days. For the same concentrations of NH4+, Mn2+, K+, Mg2+, Ca2+, Na+ and Sr2+ in a distilled water, our lab work showed that the sediment-sorbed 137Cs is displaced by ions in the order NH4+ > Mn2+ > K+ > Mg2+ ≈ Ca2+ > Na+ > Sr2+. In laboratory studies, 137Cs sorbed onto sediment was found to be less mobile in oxic soft water (Kd: 2.0 × 103 mL g-1) and more mobile in anoxic soft water (Kd: 0.2 × 103 mL g-1). In a hard water system, however, there is no significant difference in Kd values for both oxic and anoxic conditions. The sequence of Kd values is

  20. Impacts of forestry planting on primary production in upland lakes from north-west Ireland.

    Science.gov (United States)

    Stevenson, Mark A; McGowan, Suzanne; Anderson, N John; Foy, Robert H; Leavitt, Peter R; McElarney, Yvonne R; Engstrom, Daniel R; Pla-Rabés, Sergi

    2016-04-01

    Planted forests are increasing in many upland regions worldwide, but knowledge about their potential effects on algal communities of catchment lakes is relatively unknown. Here, the effects of afforestation were investigated using palaeolimnology at six upland lake sites in the north-west of Ireland subject to different extents of forest plantation cover (4-64% of catchment area). (210)Pb-dated sediment cores were analysed for carotenoid pigments from algae, stable isotopes of bulk carbon (δ(13)C) and nitrogen (δ(15)N), and C/N ratios. In lakes with >50% of their catchment area covered by plantations, there were two- to sixfold increases in pigments from cryptophytes (alloxanthin) and significant but lower increases (39-116%) in those from colonial cyanobacteria (canthaxanthin), but no response from biomarkers of total algal abundance (β-carotene). In contrast, lakes in catchments with forestry practices, although all lakes exhibited fluctuations in pigments and geochemical variables due to peat cutting and upland grazing prior to forest plantation. Taken together, patterns suggest that increases in cyanobacteria and cryptophyte abundance reflect a combination of mineral and nutrient enrichment associated with forest fertilization and organic matter influx which may have facilitated growth of mixotrophic taxa. This study demonstrates that planted forests can alter the abundance and community structure of algae in upland humic lakes of Ireland and Northern Ireland, despite long histories of prior catchment disturbance. © 2015 John Wiley & Sons Ltd.

  1. Case study of a gas plant alliance at Zama Lake

    International Nuclear Information System (INIS)

    Clark, S.

    1998-01-01

    The definition of gas processing effectiveness varies according to whether a producer emphasizes maximized production, or the greatest wellhead netback, or the greatest return on investment. The producer's vision and objectives can change over time, depending on his financial needs, changes in the investment market, shareholder perceptions, or management motivation. This article describes how a third party processor like Novagas Canada Limited (NCL) can help a producer achieve his objectives. The case of NCL's Zama Lake investment and alliance with Phillips Petroleum is used to illustrate the process. Based on this example, a third party processor can provide important midstream services such as raw gas gathering, field compression, gas processing, sales gas transmission, natural gas liquids recovery, transportation and fractionation. In addition, they can provide access to associated energy industries such as oil and electricity, or any combination of the above, by structuring their services to suit the individual needs of each producer. A third party producer can also reduce risk and cost, provide increased reliability, add new processing capacity, and increased netback. Details of how the alliance between NCL and Phillips Petroleum came about and the advantages that each partner derived from the partnership are described. By entering into an alliance with NCL, Phillips Petroleum gained value by divesting risk and acquiring low cost midstream services, while NCL gained by increasing its presence and by adding economies of scale and greater flexibility in its investment decisions

  2. Optimization of EDXRF for the study of heavy metal pollution of Lake ...

    African Journals Online (AJOL)

    The spectrometer was subsequently utilized to determine concentrations of heavy metals in water hyacinth (Eichhornia crassipes (Mart) Solms.) found growing along the shore of Lake Victoria. The optimal conditions and detection limits were determined experimentally by variation of the excitation parameters. The study ...

  3. National Water-Quality Assessment Program: Great Salt Lake basins study unit

    Science.gov (United States)

    Waddell, Kidd M.

    1999-01-01

    The Great Salt Lake Basins NAWQA study will increase the scientific understanding of the factors that influence surface- and ground-water quality. This information will benefit water-resources managers that need, but often lack, the data required to implement effective water-quality management actions and evaluate long-term changes in water quality.

  4. Preliminary oxygen-18 and deuterium study of the dynamics of Lake Titicaca

    International Nuclear Information System (INIS)

    Fontes, J.C.; Boulange, B.; Carmouze, J.P.; Florkowski, T.

    1979-01-01

    An oxygen-18 study of Lake Titicaca indicates good mixing from the surface down to 250 m. An attempt was made to assess the isotope mass balance which suggests that up to 7% of inflow is lost by leakage and surface outflow. Further measurements are needed for final checking of the isotope balance model. (author)

  5. Use of models to study forest fire behavior

    Science.gov (United States)

    Wallace L. Fons

    1961-01-01

    The U.S. Forest Service has started a laboratory study with the ultimate objective of determining model laws for fire behavior. The study includes an examination of the effect of such variables as species of wood, density of wood, moisture content, size of fuel particle, spacing, dimensions of fuel bed, wind, and slope on the rate of spread of fire and the partition of...

  6. Microbially mediated redox transformations of manganese (II) along with some other trace elements: a study from Antarctic lakes

    Digital Repository Service at National Institute of Oceanography (India)

    Krishnan, K.P.; Sinha, R.K.; Krishna, K.; Nair, S.; Singh, S.M.

    a study that was conducted in the brackish water lakes in the Larsemann Hills region (east Antarctica) is presented. The rate of in situ manganese oxidation ranged from 0.04 to 3.96 ppb day sup(-1). These lakes harbor numerous manganese...

  7. Effects of liming and ash recycling on the outflow of mercury from forest soils - a theoretical study

    International Nuclear Information System (INIS)

    Andersson, Arne; Nilsson, Ingvar

    1994-01-01

    In this report, a theoretical review is made of the probable effects that spreading of lime and woodash in forests will have on the turnover of mercury in soil and on the outflow of mercury into water systems. As a result of historic emissions of mercury into the atmosphere, a large proportion of Swedish forest land has significantly increased concentrations of mercury, which is gradually leaching into lakes and watercourses. If an increased application of lime or woodash to forest soils were to result in a major change in the outflow of mercury, it could in time have a considerable effect on the mercury concentrations in lake fish. The fish in a large number of lakes in the southern part of Sweden already have mercury concentrations which are so high as to make them unsuitable for use as food. In conclusion, the theoretical assessment indicates in general that any effects on the mercury situation in lakes as a result of liming or woodash treatment of forest land are marginal or towards the positive side. It is not likely that these treatments increases the outflow of organic matter from soil. Any worsening of the mercury situation in lakes and watercourses will therefore hardly be the result of soil changes, but rather of processes in lakes and streams. Most of the evidence, however suggests that liming/ash treatment has predominantly positive effects with regard to the lake processes that control mercury levels in fish. At this juncture, available experience indicates that the mercury situation in the environment is in no way a decisive factor in determining where and how lime or ash should be applied to forest land. 64 refs, 2 figs

  8. Biomass Carbon Content in Schima- Castanopsis Forest of Midhills of Nepal: A Case Study from Jaisikuna Community Forest, Kaski

    Directory of Open Access Journals (Sweden)

    Sushma Tripathi

    2018-01-01

    Full Text Available Community forests of Nepal’s midhills have high potentiality to sequester carbon. This paper tries to analyze the biomass carbon stock in Schima-Castanopsis forest of Jaisikuna community forests of Kaski district, Nepal. Forest area was divided into two blocks and 18 sample plots (9 in each block which were laid randomly. Diameter at Breast Height (DBH and height of trees (DBH≥5cm were measured using the DBH tape and clinometer. Leaf litter, herbs, grasses and seedlings were collected from 1*1m2 plot and fresh weight was taken. For calculating carbon biomass is multiplied by default value 0.47. The AGTB carbon content of Chilaune, Katus and other species were found 19.56 t/ha, 18.66 t/ha and 3.59 t/ha respectively. The AGTB of Chilaune dominated, Katus dominated and whole forest was found 43.78 t/ha, 39.83 t/ha and 41.81 t/ha respectively. Carbon content at leaf litter, herbs, grasses and seedlings was found 2.73 t/ha. Below ground biomass carbon at whole forest was found 6.27 t/ha. Total biomass and carbon of the forest was found 108.09 t/ha and 50.80 t/ha respectively. Difference in biomass and carbon content at Chilaune dominated block and Katus dominated block was found insignificant. This study record very low biomass carbon content than average of Nepal's forest but this variation in carbon stock is not necessarily due to dominant species present in the forest. Carbon estimation at forest of different elevation, aspect and location are recommended for further research. International Journal of EnvironmentVolume-6, Issue-4, Sep-Nov 2017, page: 72-84

  9. Changes of glacier lakes using multi-temporal remote sensing data: A case study from India

    Directory of Open Access Journals (Sweden)

    Kumar Rai Praveen

    2017-01-01

    Full Text Available The present study used the potential of Landsat multispectral data and ASTER-DEM data to identify the changes of glacier lakes in part of Chandra basin and surrounding of Himachal Pradesh of India from 1989 to 2013. The Barashigri, Chotashigri, Hamtahand Parvati glacier are the major glaciers within the area. The Landsat data of TM (1989 and 2009, ETM+ (2001 and OLI-TIRS (2013 sensors having different band combinations were analysed to monitor variation in the glacier lakes and area of glaciers and terminus whereas ASTER-DEM data was used for relief information. Glaciers terminus and glacial lakes were identified and mapped using false-colour composites (FCC with band combinations of red, near-infrared (NIR and shortwave infrared (SWIR, and a true-colour composite of red, green and NIR, of Landsat TM/ETM+ images and normalized difference water index (NDWI methods. It is observed that the number of lakes in the study area increased by 18.69% during the past 34 years while it was increased from 68 in 1989 to 89 in 2013. During the analysis, it is also found that the snow and glacier covered area within this period is also reduced from 1,317.39 to 1,125.59 km2.

  10. Lake responses following lanthanum-modified bentonite clay (Phoslock) application: an analysis of water column lanthanum data from 16 case study lakes

    NARCIS (Netherlands)

    Spears, B.M.; Lürling, M.F.L.L.W.; Yasseri, S.; Castro-Castellon, A.T.; Gibbs, M.; Meis, S.; McDonald, C.; McIntosh, J.; Sleep, D.; Oosterhout, van F.

    2013-01-01

    Phoslock is a lanthanum (La) modified bentonite clay that is being increasingly used as a geo-engineering tool for the control of legacy phosphorus (P) release from lake bed sediments to overlying waters. This study investigates the potential for negative ecological impacts from elevated La

  11. Necromass production: studies in undisturbed and logged Amazon Forests

    Science.gov (United States)

    MICHAEL PALACE; MICHAEL KELLER; HUDSON SILVA

    2008-01-01

    Necromass stocks account for up to 20% of carbon stored in tropical forests and have been estimated to be 14–19% of the annual aboveground carbon flux. Both stocks and fluxes of necromass are infrequently measured. In this study, we directly measured the production of fallen coarse necromass (>2 cm diameter) during 4.5 years using repeated surveys in undisturbed...

  12. The Fox River PCB transport study: Stepping stone to a healthy Great Lakes ecosystem

    Science.gov (United States)

    Fitzgerald, Sharon A.; Steuer, Jeffrey J.

    1996-01-01

    Polychlorinated Biphenyls (PCBs) in the Great Lakes Despite being banned since the 1970's, polychlorinated biphenyls (PCBs) continue to pose a threat to the environment because of their persistence and toxicity to organisms ranging from minute algae to fish, waterfowl, and human beings. PCBs, a set of 209 related chlorinated organic compounds, had various industrial uses such as in hydraulic fluids, cutting oils, sealants, and pesticides. Despite the manufacturing ban in the mid-1970's, PCBs remain ubiquitous in the environment. In the Laurentian Great Lakes of the Midwest. PCBs and other toxic compounds contaminate bottom sediments at almost all designated "areas of concern" (AOC)(figure 1, upper left inset). The International Joint Commission, a binational group from Canada and the United States, has identified these AOCs in their efforts to restore and protect Great Lakes ecosystems. One such area, the Fox River which flows into Green Bay, has been the focus of much scientific study in an effort to improve not only that river but to apply lessons learned to other AOCs. The final goal is a healthy Great Lakes food chain with fish and waterfowl that are safe to consume.

  13. Lead isotope ratios as a tracer for lead contamination sources: A lake Andong case study

    Directory of Open Access Journals (Sweden)

    Kim Y. H

    2013-04-01

    Full Text Available The objective of this study was to evaluate stable Pb isotope signatures as a tracer for Pb contamination in Lake Andong. For Pb isotope analysis, we collected water and sediment from Lake Andong, particles in the air, soils, and stream water, mine tailings, sludge and wastewater from zinc smelting around lake Andong watershed. The results showed that Pb isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb for zinc concentrate were 18.809 ± 0.322, 15.650 ± 0.062, and 38.728 ± 0.421, respectively. In wastewater, isotopic ratio values (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb were 17.363 ± 0.133, 15.550 ± 0.025, and 37.217 ± 0.092, respectively. Additionally, isotopic ratio values (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb for sludge were 17.515 ± 0.155, 15.537 ± 0.018, and 37.357 ± 0.173, respectively. These values were similar to those in zinc and lead concentrate originated from Canada and South America. In contrast, Pb isotope ratios of soil, tailings and sediment from Lake Andong were similar to those of Korean ore. Atmospheric particles showed different patterns of Pb isotope ratios from sediments, soils, and zinc smelting and this needs further investigation in order to identify atmospheric Pb sources.

  14. Biotic diversity interfaces with urbanization in the Lake Tahoe basin

    Science.gov (United States)

    Patricia N. Manley; Dennis D. Murphy; Lori A. Campbell; Kirsten E. Heckmann; Susan Merideth; Sean A. Parks; Monte P. Sanford; Matthew D. Schlesinger

    2006-01-01

    In the Lake Tahoe Basin, the retention of native ecosystems within urban areas may greatly enhance the landscape’s ability to maintain biotic diversity. Our study of plant, invertebrate and vertebrate species showed that many native species were present in remnant forest stands in developed areas; however, their richness and abundance declined in association with...

  15. Analysis of the Potential for Use of Floating Photovoltaic Systems on Mine Pit Lakes: Case Study at the Ssangyong Open-Pit Limestone Mine in Korea

    Directory of Open Access Journals (Sweden)

    Jinyoung Song

    2016-02-01

    Full Text Available Recently, the mining industry has introduced renewable energy technologies to resolve power supply problems at mines operating in polar regions or other remote areas, and to foster substitute industries, able to benefit from abandoned sites of exhausted mines. However, little attention has been paid to the potential placement of floating photovoltaic (PV systems operated on mine pit lakes because it was assumed that the topographic characteristics of open-pit mines are unsuitable for installing any type of PV systems. This study analyzed the potential of floating PV systems on a mine pit lake in Korea to break this misconception. Using a fish-eye lens camera and digital elevation models, a shading analysis was performed to identify the area suitable for installing a floating PV system. The layout of the floating PV system was designed in consideration of the optimal tilt angle and array spacing of the PV panels. The System Advisor Model (SAM by National Renewable Energy Laboratory, USA, was used to conduct energy simulations based on weather data and the system design. The results indicated that the proposed PV system could generate 971.57 MWh/year. The economic analysis (accounting for discount rate and a 20-year operational lifetime showed that the net present value would be $897,000 USD, and a payback period of about 12.3 years. Therefore, we could know that the economic effect of the floating PV system on the mine pit lake is relatively higher than that of PV systems in the other abandoned mines in Korea. The annual reduction of greenhouse gas emissions was analyzed and found to be 471.21 tCO2/year, which is twice the reduction effect achieved by forest restoration of an abandoned mine site. The economic feasibility of a floating PV system on a pit lake of an abandoned mine was thus established, and may be considered an efficient reuse option for abandoned mines.

  16. Does road salting confound the recovery of the microcrustacean community in an acidified lake?

    Science.gov (United States)

    Jensen, Thomas Correll; Meland, Sondre; Schartau, Ann Kristin; Walseng, Bjørn

    2014-04-15

    Numerous boreal lakes across the Northern Hemisphere recovering from acidification are experiencing a simultaneous increase in chloride (Cl) concentrations from road salting. Increasing Cl may have profound effects on the lake ecosystem. We examine if an increase in Cl from road salting has modified the recovery of the microcrustacean community in an acidified boreal lake undergoing chemical recovery (study lake). Results from the study lake were compared with an acidified "reference lake". The community changed during the study period in the study lake mainly driven by the reduction in acidification pressure. Despite the community changes and an increase in species richness, the absence of several acid sensitive species, previously occurring in the lake, indicates a delayed biological recovery relative to the chemical recovery. Moreover, changes in occurrence of acid sensitive and acid tolerant species indicated that the biological recovery was slower in the study lake compared to the "reference". Although recurrent episodes of high aluminum and low pH and decreasing Ca are likely important factors for the delay, these do not explain, for instance, the shift from Cyclops scutifer to Bosmina longispina in the study lake. Although the contribution of Cl was not significant, the correlation between Cl and the variation in microcrustacean community was twice as high in the study lake compared to the "reference". We argue that small, sheltered forest lakes may be especially sensitive to increased Cl levels, through changes in pattern of stratification, thus providing a mechanism for the shift from C. scutifer to B. longispina. The reduction of the acidification pressure seems to override the Cl effects on microcrustaceans at low Cl levels in salt-affected lakes recovering from acidification. However, prognoses for growing traffic and increasing road salting raise concern for many recovering lakes located in proximity to roads and urbanized areas. Copyright © 2014

  17. A multi-proxy approach to understanding complex responses of salt-lake catchments to climate variability and human pressure: A Late Quaternary case study from south-eastern, Spain

    Science.gov (United States)

    Jones, Samantha Elsie; Burjachs, Francesc; Ferrer-García, Carlos; Giralt, Santiago; Schulte, Lothar; Fernández-López de Pablo, Javier

    2018-03-01

    This article focuses on a former salt lake in the upper Vinalopó Valley in south-eastern Spain. The study spans the Late Pleistocene through to the Late Holocene, although with particular focus on the period between 11 ka cal BP and 3000 ka cal BP (which spans the Mesolithic and part of the Bronze Age). High resolution multi-proxy analysis (including pollen, non pollen palynomorphs, grain size, X-ray fluorescence and X-ray diffraction) was undertaken on the lake sediments. The results show strong sensitivity to both long term and small changes in the evaporation/precipitation ratio, affecting the surrounding vegetation composition, lake-biota and sediment geochemistry. To summarise the key findings the main general trends identified include: 1) Hyper-saline conditions and low lake levels at the end of the Late Glacial 2) Increasing wetness and temperatures which witnessed an expansion of mesophilic woodland taxa, lake infilling and the establishment of a more perennial lake system at the onset of the Holocene 3) An increase in solar insolation after 9 ka cal BP which saw the re-establishment of pine forests 4) A continued trend towards increasing dryness (climatic optimum) at 7 ka cal BP but with continued freshwater input 5) An increase in sclerophyllous open woody vegetation (anthropogenic?), and increasing wetness (climatic?) is represented in the lake record between 5.9 and 3 ka cal BP 6) The Holocene was also punctuated by several aridity pulses, the most prominent corresponding to the 8.2 ka cal BP event. These events, despite a paucity of well dated archaeological sites in the surrounding area, likely altered the carrying capacity of this area both regionally and locally, particularly during the Mesolithic-Neolithic transition, in terms of fresh water supply for human/animal consumption, wild plant food reserves and suitable land for crop growth.

  18. Forest cover dynamics analysis and prediction modelling using logistic regression model (case study: forest cover at Indragiri Hulu Regency, Riau Province)

    Science.gov (United States)

    Nahib, Irmadi; Suryanta, Jaka

    2017-01-01

    Forest destruction, climate change and global warming could reduce an indirect forest benefit because forest is the largest carbon sink and it plays a very important role in global carbon cycle. To support Reducing Emissions from Deforestation and Forest Degradation (REDD +) program, people pay attention of forest cover changes as the basis for calculating carbon stock changes. This study try to explore the forest cover dynamics as well as the prediction model of forest cover in Indragiri Hulu Regency, Riau Province Indonesia. The study aims to analyse some various explanatory variables associated with forest conversion processes and predict forest cover change using logistic regression model (LRM). The main data used in this study is Land use/cover map (1990 - 2011). Performance of developed model was assessed through a comparison of the predicted model of forest cover change and the actual forest cover in 2011. The analysis result showed that forest cover has decreased continuously between 1990 and 2011, up to the loss of 165,284.82 ha (35.19 %) of forest area. The LRM successfully predicted the forest cover for the period 2010 with reasonably high accuracy (ROC = 92.97 % and 70.26 %).

  19. Use of forest biomass to provide energy in a context of sustainable rural development - Three case studies

    International Nuclear Information System (INIS)

    Villa Lopera, Jose Antonio

    2000-01-01

    The author includes topics like energy and global climatic change; sustainable development and study of cases (conservation and restoration of forests in the Atrato, pacific Colombian, forest handling, forest handling and forest systems in the Colombian Amazonian and conversion of subjected lands to cattle rising and itinerant agriculture to forest and other systems

  20. Resilience of alternative stable states during the recovery of shallow lakes from eutrophication: Lake Veluwe as a case study

    NARCIS (Netherlands)

    Ibelings, B.W.; Portielje, R.; Lammens, E.H.R.R.; Meijer, M.L.; Noordhuis, R.; van den Berg, Marcel S.; Joosse, W.; Scheffer, M.

    2007-01-01

    In this paper we analyze a long-term dataset on the recovery from eutrophication of Lake Veluwe (The Netherlands). Clear hysteresis was observed in a number of ecosystem variables: the route to recovery differed significantly from the route that led to loss of clear water. The macrophyte dominated

  1. Variation in tree mortality and regeneration affect forest carbon recovery following fuel treatments and wildfire in the Lake Tahoe Basin, California, USA

    Science.gov (United States)

    2012-01-01

    Background Forest fuel treatments have been proposed as tools to stabilize carbon stocks in fire-prone forests in the Western U.S.A. Although fuel treatments such as thinning and burning are known to immediately reduce forest carbon stocks, there are suggestions that these losses may be paid back over the long-term if treatments sufficiently reduce future wildfire severity, or prevent deforestation. Although fire severity and post-fire tree regeneration have been indicated as important influences on long-term carbon dynamics, it remains unclear how natural variability in these processes might affect the ability of fuel treatments to protect forest carbon resources. We surveyed a wildfire where fuel treatments were put in place before fire and estimated the short-term impact of treatment and wildfire on aboveground carbon stocks at our study site. We then used a common vegetation growth simulator in conjunction with sensitivity analysis techniques to assess how predicted timescales of carbon recovery after fire are sensitive to variation in rates of fire-related tree mortality, and post-fire tree regeneration. Results We found that fuel reduction treatments were successful at ameliorating fire severity at our study site by removing an estimated 36% of aboveground biomass. Treated and untreated stands stored similar amounts of carbon three years after wildfire, but differences in fire severity were such that untreated stands maintained only 7% of aboveground carbon as live trees, versus 51% in treated stands. Over the long-term, our simulations suggest that treated stands in our study area will recover baseline carbon storage 10–35 years more quickly than untreated stands. Our sensitivity analysis found that rates of fire-related tree mortality strongly influence estimates of post-fire carbon recovery. Rates of regeneration were less influential on recovery timing, except when fire severity was high. Conclusions Our ability to predict the response of forest

  2. Variation in tree mortality and regeneration affect forest carbon recovery following fuel treatments and wildfire in the Lake Tahoe Basin, California, USA.

    Science.gov (United States)

    Carlson, Chris H; Dobrowski, Solomon Z; Safford, Hugh D

    2012-06-28

    Forest fuel treatments have been proposed as tools to stabilize carbon stocks in fire-prone forests in the Western U.S.A. Although fuel treatments such as thinning and burning are known to immediately reduce forest carbon stocks, there are suggestions that these losses may be paid back over the long-term if treatments sufficiently reduce future wildfire severity, or prevent deforestation. Although fire severity and post-fire tree regeneration have been indicated as important influences on long-term carbon dynamics, it remains unclear how natural variability in these processes might affect the ability of fuel treatments to protect forest carbon resources. We surveyed a wildfire where fuel treatments were put in place before fire and estimated the short-term impact of treatment and wildfire on aboveground carbon stocks at our study site. We then used a common vegetation growth simulator in conjunction with sensitivity analysis techniques to assess how predicted timescales of carbon recovery after fire are sensitive to variation in rates of fire-related tree mortality, and post-fire tree regeneration. We found that fuel reduction treatments were successful at ameliorating fire severity at our study site by removing an estimated 36% of aboveground biomass. Treated and untreated stands stored similar amounts of carbon three years after wildfire, but differences in fire severity were such that untreated stands maintained only 7% of aboveground carbon as live trees, versus 51% in treated stands. Over the long-term, our simulations suggest that treated stands in our study area will recover baseline carbon storage 10-35 years more quickly than untreated stands. Our sensitivity analysis found that rates of fire-related tree mortality strongly influence estimates of post-fire carbon recovery. Rates of regeneration were less influential on recovery timing, except when fire severity was high. Our ability to predict the response of forest carbon resources to anthropogenic and

  3. Variation in tree mortality and regeneration affect forest carbon recovery following fuel treatments and wildfire in the Lake Tahoe Basin, California, USA

    Directory of Open Access Journals (Sweden)

    Carlson Chris H

    2012-06-01

    Full Text Available Abstract Background Forest fuel treatments have been proposed as tools to stabilize carbon stocks in fire-prone forests in the Western U.S.A. Although fuel treatments such as thinning and burning are known to immediately reduce forest carbon stocks, there are suggestions that these losses may be paid back over the long-term if treatments sufficiently reduce future wildfire severity, or prevent deforestation. Although fire severity and post-fire tree regeneration have been indicated as important influences on long-term carbon dynamics, it remains unclear how natural variability in these processes might affect the ability of fuel treatments to protect forest carbon resources. We surveyed a wildfire where fuel treatments were put in place before fire and estimated the short-term impact of treatment and wildfire on aboveground carbon stocks at our study site. We then used a common vegetation growth simulator in conjunction with sensitivity analysis techniques to assess how predicted timescales of carbon recovery after fire are sensitive to variation in rates of fire-related tree mortality, and post-fire tree regeneration. Results We found that fuel reduction treatments were successful at ameliorating fire severity at our study site by removing an estimated 36% of aboveground biomass. Treated and untreated stands stored similar amounts of carbon three years after wildfire, but differences in fire severity were such that untreated stands maintained only 7% of aboveground carbon as live trees, versus 51% in treated stands. Over the long-term, our simulations suggest that treated stands in our study area will recover baseline carbon storage 10–35 years more quickly than untreated stands. Our sensitivity analysis found that rates of fire-related tree mortality strongly influence estimates of post-fire carbon recovery. Rates of regeneration were less influential on recovery timing, except when fire severity was high. Conclusions Our ability to predict

  4. Challenges in accounting the forests - a Latvian case study

    Directory of Open Access Journals (Sweden)

    Evija Grege-Staltmane

    2010-06-01

    Full Text Available Forest has a long production cycle. Therefore forest bookkeeping has specific characteristics. However accounting for forest activities has received little attention from accounting researchers. The release of International Accounting Standard 41 "Agriculture" (IAS 41 established a single accounting system for forest assets. The paper analyzes application of IAS 41 which regulates forest accounting. Practice of international forestry companies is examined, and current forest accounting situation in Latvia is investigated. The main factors affecting valuation of a forest in its fair value are discussed and major problems in forest accounting are illuminated. The research indicates that land value and standing timber value should be recorded separately and standing timber should be estimated at its fair value. Despite the attempt of the International Accounting Standard Board to improve the accounting with IAS 41 for biological assets, much enhancement in forest accounting is still needed. 

  5. Challenges in accounting the forests - a Latvian case study

    Directory of Open Access Journals (Sweden)

    Evija Grege-Staltmane

    2010-09-01

    Full Text Available Forest has a long production cycle. Therefore forest bookkeepinghas specific characteristics. However accounting for forest activities has received little attention from accounting researchers. The release of International Accounting Standard 41 "Agriculture" (IAS 41 established a single accounting system for forest assets. The paper analyzes application of IAS 41 which regulates forest accounting. Practice of international forestry companies is examined, and current forest accounting situation in Latvia is investigated. The main factors affecting valuation of a forest in its fair value are discussed and major problems in forest accounting are illuminated.The research indicates that land value and standing timber valueshould be recorded separately and standing timber should be estimated at its fair value. Despite the attempt of the International Accounting Standard Board to improve the accounting with IAS 41 for biological assets, much enhancement in forest accounting is still needed.

  6. Values, Ethics, and Attitudes Toward National Forest Management: An Empirical Study

    Science.gov (United States)

    Robert Manning; William Valliere; Ben Minteer

    1999-01-01

    This study measures environmental values and ethics and explores their relationships to attitudes toward national forest management. The principal research methods were literature review and a survey of Vermont residents concerning management of the Green Mountain National Forest. Descriptive findings suggest respondents (1) favor nonmaterial values of national forests...

  7. A study of the influence of forest gaps on fire–atmosphere interactions

    Science.gov (United States)

    Michael T. Kiefer; Warren E. Heilman; Shiyuan Zhong; Joseph J. (Jay) Charney; Xindi (Randy) Bian

    2016-01-01

    Much uncertainty exists regarding the possible role that gaps in forest canopies play in modulating fire–atmosphere interactions in otherwise horizontally homogeneous forests. This study examines the influence of gaps in forest canopies on atmospheric perturbations induced by a low-intensity fire using the ARPS-CANOPY model, a version of the Advanced Regional...

  8. Small Boreal Lake Ecosystem Evolution under the Influence of Natural and Anthropogenic Factors: Results of Multidisciplinary Long-Term Study

    Directory of Open Access Journals (Sweden)

    Liudmila Shirokova

    2016-07-01

    Full Text Available Small aquatic ecosystems of the boreal zone are known to be most sensitive indicators of on-going environmental change as well as local anthropogenic pressure, while being highly vulnerable to external impacts. Compared to rather detailed knowledge of the evolution of large and small lakes in Scandinavia and Canada, and large lakes in Eurasia, highly abundant small boreal lakes of northwest Russia have received very little attention, although they may become important centers of attraction of growing rural population in the near future. Here we present the results of a multidisciplinary, multi-annual study of a small boreal humic lake of NW Russia. A shallow (3 m and a deep (16 m site of this lake were regularly sampled for a range of chemical and biological parameters. Average multi-daily, summer-time values of the epilimnion (upper oxygenated layer of the lake provided indications of possible trends in temperature, nutrients, and bacterio-plankton concentration that revealed the local pollution impact in the shallow zone and overall environmental trend in the deep sampling point of the lake. Organic phosphorus, nitrate, and lead were found to be most efficient tracers of local anthropogenic pollution, especially visible in the surface layer of the shallow site of the lake. Cycling of trace elements between the epilimnion and hypolimnion is tightly linked to dissolved organic matter speciation and size fractionation due to the dominance of organic and organo-ferric colloids. The capacity of lake self-purification depends on the ratio of primary productivity to mineralization of organic matter. This ratio remained >1 both during winter and summer periods, which suggests a high potential of lake recovery from the input of allochthonous dissolved organic matter and local anthropogenic pollution.

  9. Biodiversity and productivity of Rana Patap Sagar lake a thermo-ecological study

    International Nuclear Information System (INIS)

    Verma, P.C.; Sharma, L.L.

    2007-01-01

    Rana Pratap Sagar (RPS) in Rajasthan, is a man made fresh water reservoir and is balancing between Gandhi Sagar on upstream and Jawahar sagar on its down stream. On its eastern bank there exists Rawatbhata Site, comprising of multi -nuclear facilities. There are four PHWR units of Rajasthan Atomic Power Station (RAPS) which are in operations, two are under construction and another two are under advanced stage of planning. In addition to nuclear power plants the Site also houses a Heavy Water Plant and other allied facilities such as cobalt facility and waste management facilities. RAPS draws water from RPS lake through a 300 m long conduit pipe located at lake bottom about 20 m below the surface. Duly treated low level radioactive liquid effluents from RAPS facilities are injected to the warmed condenser outlet and then allowed to discharge to RPS in a controlled manner. The warm water is likely to remain at the surface and get mixed with lake water and cooled due to dilutions, evaporation from lake surface and wind currents. The heat release to the RPS lake through condenser outlet may effect the microbiological and water quality parameters, planktonic biodiversity, fish productivity etc. and thus it is imperative to conduct the thermal ecological study to assess the extent of maturation of the water body to identify its present trophic status in terms of eutrophication. This presentation gives the details of thermal ecological studies carried out at Rana Pratap Sagar lake during 2002-2004 under DAE-BRNS project.. The study includes monitoring of several water quality parameters, biological and bacterial parameters and data on thermal stratification in respect of RPS reservoir. The data so obtained were subjected to statistical analysis. The probabilistic and possibilistic approaches have been applied to evaluate ecological risk. The study reveals that there is no adverse effect on RPS water quality owing to receive the warmed effluents from RAPS. Furthermore, it

  10. Lake Afdera: a threatened saline lake in Ethiopia | Getahun | SINET ...

    African Journals Online (AJOL)

    Lake Afdera is a saline lake located in the Afar region, Northern Ethiopia. Because of its inaccessibility it is one of the least studied lakes of the country. It supports life including three species of fish of which two are endemic. Recently, reports are coming out that this lake is used for salt extraction. This paper gives some ...

  11. Correlation Analysis of NINO3.4 SST and Inland Lake Level Variations Monitored with Satellite Altimetry: Case Studies of Lakes Hongze, Khanka, La-ang, Ulungur, Issyk-kul and Baikal

    Directory of Open Access Journals (Sweden)

    Jinyun Guo

    2011-01-01

    Full Text Available Climate change can sometimes be reflected in variations in lake levels, thus understanding variations in lake levels and their relationship to climate change plays an important role in studying climate change. In this study, about 10 years of Topex/Poseidon (T/P altimetric data and 6 years of Jason-1 data were used to compute time series of level variations of six lakes in the Central and East Asia. The study sites were Hongze, La-ang, Ulungur, Khanka, Issyk-kul and Baikal Lakes. Time series of level variations were analyzed by means of the wavelet spectrum for inter-annual (between 2 to 4 years, annual and semiannual signals. Since 2000, water level variations of Issyk-kul, Ulungur and Khanka lakes were larger than those of Baikal and Hongze. Correlations between the NINO3.4 sea surface temperature (SST and the level variations of the six lakes were analyzed. For Baikal and Khanka Lakes, the correlations were significant (+0.3834 and +0.3334 for 3 - 5 months after the occurrence of ENSO, while the correlation for La-ang Lake was the weakest (< 0.1, indicating that ENSO showed a lag influence on variation in lake levels in the Central and East Asia.

  12. Stakeholder participation to watershed management: A case study from Beysehir Lake Basin.

    Science.gov (United States)

    Yavuz, Fadim; Baycan, Tozin

    2015-01-01

    This study addresses Beyehir Lake Basin, which is the largest freshwater lake in Turkey. The aim of the study was to explore the knowledge, perceptions and behaviors of local communities regarding; the critical problems of the basin; technical and political situation of the water management in the basin; possible strategies ensuring positive change towards the sustainability of the basin; and the watershed management strategies which could contribute to success in this case. The participatory level of the local water users of the basin was also examined. The results revealed that local communities were aware of the basin's problems and contribution of the participatory approaches to watershed management. Also, collaboration between the public and public institutions was accepted as key to successful watershed management. The stakeholders, who considered that current water policies to solve the problems of the basin were ineffectual, relied on the local environmental groups more than central government and local authorities regarding their water policies.

  13. Study of Morphologic Change in Poyang Lake Basin Caused by Sand Dredging Using Multi-temporal Landsat Images and DEMs

    Science.gov (United States)

    Qi, S.; Zhang, X.; Wang, D.; Zhu, J.; Fang, C.

    2014-11-01

    Sand dredging has been practiced in rivers, lakes, harbours and coastal areas in recent years in China mostly because of demand from construction industry as building material. Sand dredging has disturbed aquatic ecosystems by affecting hydrological processes, increasing content of suspended sediments and reducing water clarity. Poyang Lake, connecting with Yangtze River in the lower reaches of the Yangtze River, is the largest fresh water lake in China. Sand dredging in Poyang Lake has been intensified since 2001 because such practice was banned in Yangtze River and profitable. In this study, the morphologic change caused by sand dredging in Poyang Lake basin was analysed by overlaying two DEMs acquired in 1952 and 2010 respectively. Since the reflectance of middle infrared band for sand dredging vessel is much higher than that of water surface, sand dredging vessels were showed as isolated grey points and can be counted in the middle infrared band in 12 Landsat images acquired in flooding season during 2000~2010. Another two Landsat images (with low water level before 2000 and after 2010) were used to evaluate the morphologic change by comparing inundation extent and shoreline shape. The following results was obtained: (1) vessels for sand dredging are mainly distributed in the north of Poyang Lake before 2007, but the dredging area was enlarged to the central region and even to Gan River; (2) sand dredging area reached to about 260.4 km2 and is mainly distributed in the north of Songmen Mountain and has been enlarged to central of Poyang Lake from the distribution of sand vessels since 2007. Sand dredged from Poyang Lake was about 1.99 × 109 m3 or 2448 Mt assuming sediment bulk density of 1.23 t m-3. It means that the magnitude of sand mining during 2001-2010 is almost ten times of sand depositions in Poyang Lake during 1955-2010; (3) Sand dredging in Poyang Lake has alternated the lake capacity and discharge section area, some of the watercourse in the

  14. Conifer density within lake catchments predicts fish mercury concentrations in remote subalpine lakes

    Science.gov (United States)

    Eagles-Smith, Collin A.; Herring, Garth; Johnson, Branden L.; Graw, Rick

    2016-01-01

    Remote high-elevation lakes represent unique environments for evaluating the bioaccumulation of atmospherically deposited mercury through freshwater food webs, as well as for evaluating the relative importance of mercury loading versus landscape influences on mercury bioaccumulation. The increase in mercury deposition to these systems over the past century, coupled with their limited exposure to direct anthropogenic disturbance make them useful indicators for estimating how changes in mercury emissions may propagate to changes in Hg bioaccumulation and ecological risk. We evaluated mercury concentrations in resident fish from 28 high-elevation, sub-alpine lakes in the Pacific Northwest region of the United States. Fish total mercury (THg) concentrations ranged from 4 to 438 ng/g wet weight, with a geometric mean concentration (±standard error) of 43 ± 2 ng/g ww. Fish THg concentrations were negatively correlated with relative condition factor, indicating that faster growing fish that are in better condition have lower THg concentrations. Across the 28 study lakes, mean THg concentrations of resident salmonid fishes varied as much as 18-fold among lakes. We used a hierarchal statistical approach to evaluate the relative importance of physiological, limnological, and catchment drivers of fish Hg concentrations. Our top statistical model explained 87% of the variability in fish THg concentrations among lakes with four key landscape and limnological variables: catchment conifer density (basal area of conifers within a lake's catchment), lake surface area, aqueous dissolved sulfate, and dissolved organic carbon. Conifer density within a lake's catchment was the most important variable explaining fish THg concentrations across lakes, with THg concentrations differing by more than 400 percent across the forest density spectrum. These results illustrate the importance of landscape characteristics in controlling mercury bioaccumulation in fish.

  15. Modeling forest mortality caused by drought stress: implications for climate change

    Science.gov (United States)

    Eric J Gustafson; Brian R. Sturtevant

    2013-01-01

    Climate change is expected to affect forest landscape dynamics in many ways, but it is possible that the most important direct impact of climate change will be drought stress. We combined data from weather stations and forest inventory plots (FIA) across the upper Great Lakes region (USA) to study the relationship between measures of drought stress and mortality for...

  16. Feasibility Study of Shoreline Protection and Lake Level Regulation for Lake Ontario. Reconnaissance Report. Volume II. Appendices.

    Science.gov (United States)

    1981-11-01

    Wildlife resources in the Lake Ontario drainage basin will continue to provide outdoor opportunities for hunting, birdwatching , photography and other...that pass through the Braddock Bay area, it has become a prime location for the observation of such birds by birdwatchers . In the 1920’s and 1930’s bald...Consequently, it is a popular birdwatching location. Green herons are known to roost and nest in the area while great horned owls and red-tailed hawks

  17. Archaeological Survey of Cooper Lake, Number 7. 1989. Cultural Resource Studies for Cooper Lake, Hopkins and Delta Counties, Texas

    Science.gov (United States)

    1989-01-01

    Tetromeryx shuleri), bison, camel , and possibly a large cat from Lake Tawakoni. Informant Jimmy Of all the avocational collectors interviewed, Ross has...Monthly Press, Austin. Stephenson, Robert L. United States Department of Agriculture (USDA) 1950 Archaeological Survey of Texarkana 1975 Soil Taxonomy ...Philip Ceramic System in Southwestern Pottery 1958 Application of the Wheat-Gifford-Wasley Analysis. American Antiquity 12:226-237. Taxonomy to Eastern

  18. The As-MnO2 redox reaction: coal-mine lake geochemistry and experimental studies

    Science.gov (United States)

    Roman-Ross, G.; Tournassat, C.; Charlet, L.

    2001-05-01

    After the closure of the coal mining activities in the Massif Central range, France, several lakes were formed as a consequence of mine collapse and lack of water pumping. The old mines, located at the bottom of lakes, are a certified source of As and heavy metals. Nevertheless, at present, these lakes are used for recreative activities and represent a potential source of drinking water. During a time period of one year, we have monitored the water column of one of these lakes in order to identify the geochemical processes that control water quality. In addition, we have performed laboratory experiences to study the influence of manganese oxides on the As especiation. Based on in situ and laboratory measures, we can describe this lake as permanently stratified with a pronounced oxycline and negligible dissolved oxygen below 6 and 7 m. The maintenance of the stratification results from the high total dissolved solids and high density of bottom waters. The evolution in time and depth of the different redox sensitive species shows the typical chemical succession of electron acceptor reactions with organic matter during the course of sedimentation. The hipolimnium, rich in As (7 mM), displays a strong contrast with the values registered in the upper oxic layer where As concentrations are low (<1mM) and the water quality is appropriate to human consummation. In spite of anoxic conditions, As(V) is the most abundant arsenic species closely linked to Mn mobility. To asses the role of manganese oxides in the As(III)-As(V) redox transformation, we have performed several laboratory experiments on Hexagonal-Birnessite at pH 5. Our results based on kinetics experiments and EXAFS analyses of solid phases, show that As(III) is oxidised by Mn(IV) and Mn(III) resulting in dissolving the solid and releasing As(V) and Mn(II) into the solution. In contrast with previous published works by other authors, kinetics of the oxidation strongly depends on the cristallinity of birnessite

  19. Impact of climate variability on terrestrial environment in Western Europe between 45 and 9 kyr cal. BP: vegetation dynamics recorded by the Bergsee Lake (Black Forest, Germany).

    Science.gov (United States)

    Duprat-Oualid, Fanny; Begeot, Carole; Rius, Damien; Millet, Laurent; Magny, Michel

    2016-04-01

    Between 9 and 45 kyr cal. BP, two great transitions lead the global climate system to evolve from the Last-Glacial period (115-14.7 kyr cal. BP), to two successive warmer periods, the Late-Glacial Interstadial (14.7-11.7 kyr cal. BP) and the Holocene (11.7-0 kyr cal. BP). δ18O variations recorded in Greenland ice cores (GRIP & NGRIP) revealed high frequency climate variability within the Last Glacial. These reference isotopic records highlighted a succession of centennial-to-millennial warm/cold events, the so-called Greenland Interstadials (GI) and Greenland Stadials (GS). The number continental records about the period 14.7-0 kyr cal. BP is substantial. This allowed to understand the vegetation dynamics in response to climate changes this period at the North-Atlantic scale. However, sequences covering the glacial period (beyond 20 kyr cal.BP) remain rare, because of hiatuses mostly due to local glaciers. Therefore, sedimentary continuous records of vegetation dynamics are still needed to better understand climate changes during the Last Glacial in Western Europe (Heiri et al. 2014). Here we present a new high-resolution pollen record from Lake Bergsee (47°34'20''N, 7°56'11''E, 382 m a.s.l). This lake is located south of Black Forest and north of the Alps, beyond the zone of glaciers maximal extension. Therefore it could have recorded the whole last climatic cycle, i.e. 120-0 kyr cal. BP. In 2013, a 29 m long core was extracted from the Bergsee. According to the depth-age model based on 14C AMS dating and the Laacher See Tephra (LST), the record spans continuously at least the last 45 kyrs. The first series of pollen analysis, focused on the 45-9 kyr cal. BP time window, allows us to reconstruct a precise, faithful and continuous vegetation history at the centennial scale. This high temporal resolution enabled to assess the response of vegetation to secular climate events (e.g. GI-4 = 200 yrs). First, our results show that vegetation responded to climate

  20. Great Lakes O shore Wind Project: Utility and Regional Integration Study

    Energy Technology Data Exchange (ETDEWEB)

    Sajadi, Amirhossein [Case Western Reserve Univ., Cleveland, OH (United States); Loparo, Kenneth A. [Case Western Reserve Univ., Cleveland, OH (United States); D' Aquila, Robert [General Electric (GE), Albany, NY (United States); Clark, Kara [National Renewable Energy Lab. (NREL), Golden, CO (United States); Waligorski, Joseph G. [FirstEnergy, Akron, OH (United States); Baker, Scott [PJM Interconnection, Audubon, PA (United States)

    2016-06-30

    This project aims to identify transmission system upgrades needed to facilitate offshore wind projects as well as operational impacts of offshore generation on operation of the regional transmission system in the Great Lakes region. A simulation model of the US Eastern Interconnection was used as the test system as a case study for investigating the impact of the integration of a 1000MW offshore wind farm operating in Lake Erie into FirstEnergy/PJM service territory. The findings of this research provide recommendations on offshore wind integration scenarios, the locations of points of interconnection, wind profile modeling and simulation, and computational methods to quantify performance, along with operating changes and equipment upgrades needed to mitigate system performance issues introduced by an offshore wind project.

  1. Forest hydrology

    Science.gov (United States)

    Ge Sun; Devendra Amatya; Steve McNulty

    2016-01-01

    Forest hydrology studies the distribution, storage, movement, and quality of water and the hydrological processes in forest-dominated ecosystems. Forest hydrological science is regarded as the foundation of modern integrated water¬shed management. This chapter provides an overview of the history of forest hydrology and basic principles of this unique branch of...

  2. Conventional and New Ways of Governing Forest Threats: A Study of Stakeholder Coherence in Sweden

    Science.gov (United States)

    Eriksson, Louise

    2018-01-01

    Based on a framework for analyzing stakeholder coherence horizontally and vertically, the present study examined the governance of forest threats in Sweden. Opinions of forest risk governance in stakeholder groups with and without a connection to private forestry were compared ( n = 2496) and the opinions were analyzed in relation to current governance practices. More specifically, forest threat appraisals, trust in the Swedish Forest Agency (SFA), and the acceptability of forest risk policy measures directed at private forest owners were assessed. Results revealed an overall coherence between different stakeholders in this context. However, the groups differed in, for example, the acceptability of the hypothetical regulative measure aiming to reduce damages threatening the forest long-term (e.g., climate change). Furthermore, an extensive use of advice for a fee may challenge particularly the internal, but also the external, legitimacy of forest risk governance. The forest owner stakeholder group showed lower threat appraisals when evaluating threat to one's own forest rather than to the Swedish forest, except regarding browsing by animals. Regulations were not disapproved of in any of the stakeholder groups, although the forest owner group generally displayed higher acceptability of encouraging measures compared to the general public. Trust in the SFA was furthermore confirmed as an important driver of policy acceptability, and higher threat appraisals of novel threats, such as climate change and fire, resulted in a higher acceptability of measures less central or new in this context. The value of analyzing stakeholder coherence for natural resource management and governance is discussed.

  3. Absolute palaeointensity study of the Mono Lake excursion recorded by New Zealand basalts

    Science.gov (United States)

    Cassidy, John; Hill, Mimi J.

    2009-02-01

    One of the geomagnetic excursions recorded in basalts of the Auckland volcanic field, New Zealand, has recently been correlated unequivocally with the Mono Lake excursion, making it the only confirmed record from the southern hemisphere. This record is also exceptional in occurring in five separate monogenetic basaltic volcanoes. Absolute palaeointensity determinations using the microwave technique, based on a comprehensive suite of samples of the Auckland basalts recording the excursion, show that the geomagnetic field in New Zealand at the time of the Mono Lake excursion was reduced to about 14 μT i.e. to 30% of its normal value. This result confirms previous estimates based on more limited sampling. In addition, it provides a comparison of the microwave and LDT-DHT Shaw methods of measuring palaeointensity, which give results that are statistically indistinguishable. The palaeointensities determined from the five different volcanoes are also indistinguishable, though the palaeodirection data suggest that a very small segment of the VGP path may have been recorded. This study confirms the reliability of palaeointensity and palaeodirection determinations from these particular New Zealand basalts, which together with their definitive 40Ar/ 39Ar ages, establishes this record of the Mono Lake excursion as one of the best documented. Consequently, there is significant potential in searching for records of this excursion elsewhere in the Pacific region for use as a stratigraphic marker in studies of recent volcanism and palaeoclimate reconstructions.

  4. Cyanobacteria Dominance in Lakes and Evaluation of Its Predictors: a Study of Southern Appalachians Ecoregion, USA

    Directory of Open Access Journals (Sweden)

    Ghaffar Sajeela

    2016-01-01

    Full Text Available Owing to their ecological and economic implications, the abundance of cyanobacteria has been an important subject in aquatic ecology. There has been a debate about which nutrients are a better predictor of cyanobacteria abundance, total nitrogen (TN, total phosphorus (TP or nitrogen to phosphorus ratio (N:P. A classic study by Downing and coworkers in 2001 concluded that total N and total P are better predictors than TN:TP ratio. We picked lakes from a different region of the US, the Southern Appalachians (SAP, to test the same hypotheses using the National Lakes Assessment (NLA, 2007 database. This dataset consists of 116 selected sampling sites throughout the ecoregion. In this study, total cyanobacteria abundance was related to three predictors (N, P and N:P using linear regression, non-parametric statistics and boosted regression trees (BRTs. Total N and total P were more strongly correlated to cyanobacteria abundance than N:P. Partial dependence plots from BRT analysis confirmed results of correlations showing higher relative influence values of TN and TP on cyanobacteria abundance. An important observation from both analyses was that cyanobacteria abundance increased rapidly with increasing TP above 5 μg TP/L. This is a similar response relationship between abundance of cyanobacteria and TP as reported by Downing et al. (2001. These TP thresholds for cyanobacteria dominance are important for TP management targets to control blooms in lakes.

  5. [Study on trace elements of lake sediments by ICP-AES and XRF core scanning].

    Science.gov (United States)

    Cheng, Ai-Ying; Yu, Jun-Qing; Gao, Chun-Liang; Zhang, Li-Sha; He, Xian-Hu

    2013-07-01

    It is the first time to study sediment of Toson lake in Qaidam Basin. Trace elements including Cd, Cr, Cu, Zn and Pb in lake sediment were measured by ICP-AES method, studied and optimized from different resolution methods respectively, and finally determined a optimum pretreatment system for sediment of Toson lake, namely, HCl-HNO3-HF-HClO4-H2O2 system in the proportions of 5 : 5 : 5 : 1 : 1 was determined. At the same time, the data measured by XRF core scanning were compared, the use of moisture content correction method was analyzed, and the influence of the moisture content on the scanning method was discussed. The results showed that, compared to the background value, the contents of Cd and Zn were a little higher, the content of Cr, Cu and Pb was within the background value limits. XRF core scanning was controlled by sediment elements as well as water content in sediment to some extent. The results by the two methods showed a significant positive correlation, with the correlation coefficient up to 0.673-0.925, and they have a great comparability.

  6. VALUE OF ECOLOGIC COMPONENT IN FOREST MANAGEMENT DECISION MAKING. CASE STUDY: FORESTS ADJACENT TO BUCHAREST, ROMANIA

    Directory of Open Access Journals (Sweden)

    Carmen Valentina RADULESCU

    2016-06-01

    Full Text Available To say environment management is, nowadays, of outmost importance for any ecosystem concerned in an understatement; nevertheless, in Romania, especially – as least, since the present paper analyses Romanian ecologic statu quo – improving forest management, so to speak, in Romania, is all the more important, since social and economic decisionmaking as to forests (e.g. forests close to Romania’s capital, Bucharest includes necessarily an ecologic component. The main issue is how to make this component as visible and important as posible, without simultaneously reducing the economic and social components.

  7. 75 FR 64691 - Information Collection; Land Between The Lakes (LBL) Communication Effectiveness Study

    Science.gov (United States)

    2010-10-20

    ... tourism promotions, as well as LBL's own Web site. The Forest Service is proposing a study designed to assess the impact of communication avenues such as promotions and other information sources on current and potential visitors to the LBL. The study will be conducted and led by LBL's own Social Science and...

  8. Uncertainty of large-area estimates of indicators of forest structural gamma diversity: A study based on national forest inventory data

    Science.gov (United States)

    Susanne Winter; Andreas Böck; Ronald E. McRoberts

    2012-01-01

    Tree diameter and height are commonly measured forest structural variables, and indicators based on them are candidates for assessing forest diversity. We conducted our study on the uncertainty of estimates for mostly large geographic scales for four indicators of forest structural gamma diversity: mean tree diameter, mean tree height, and standard deviations of tree...

  9. Software applications to three-dimensional visualization of forest landscapes -- A case study demontrating the use of visual nature studio (VNS) in visualizing fire spread in forest landscapes

    Science.gov (United States)

    Brian J. Williams; Bo Song; Chou Chiao-Ying; Thomas M. Williams; John. Hom

    2010-01-01

    Three-dimensional (3D) visualization is a useful tool that depicts virtual forest landscapes on computer. Previous studies in visualization have required high end computer hardware and specialized technical skills. A virtual forest landscape can be used to show different effects of disturbances and management scenarios on a computer, which allows observation of forest...

  10. Radon as a natural geochemical tracer for study of groundwater discharge into lakes

    International Nuclear Information System (INIS)

    Schmidt, Axel

    2008-01-01

    In the presented work the suitability of the naturally occurring radioactive noble gas isotope radon-222 for qualitative and quantitative description of groundwater discharge into lakes was studied. Basis of these investigations was the development of two innovative techniques for the on-site determination of radon in water. In the ex-situ radon measurement procedure, water from the source concerned is taken up in an exchange cell used for this purpose. Inside this cell, the radon dissolved in water is transferred via diffusion into a closed counter-flow of air and subsequently detected by a radon-in-air monitor. Where the in-situ radon determination is concerned, a module composed of a semipermeable membrane is introduced into a water column. Subsequently, the radon dissolved in the water body diffuses through the membrane into the corresponding air flow, by means of which it is transferred into a radon-in-air monitor and is detected. Combination of the developed mobile radon extraction techniques with a suitable and portable radon monitor allow the detection of radon-222 with sufficient accuracy (smaller 20 %) in groundwater as well as in surface waters, i.e., within a broad range of concentrations. Radon-222 was subsequently used to characterize groundwater discharge into a meromictic and a dimictic lake, i.e. two types of lake basically distinct from each other with respect to their water circulation properties were investigated. The use of the noble gas isotope radon-222 as a geochemical tracer makes the application of on-site detection techniques possible and that this in turn permits a rapid, reliable, and cost-effective assessment of groundwater discharge rates into lake water bodies

  11. Radon as a natural geochemical tracer for study of groundwater discharge into lakes

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Axel

    2008-06-27

    In the presented work the suitability of the naturally occurring radioactive noble gas isotope radon-222 for qualitative and quantitative description of groundwater discharge into lakes was studied. Basis of these investigations was the development of two innovative techniques for the on-site determination of radon in water. In the ex-situ radon measurement procedure, water from the source concerned is taken up in an exchange cell used for this purpose. Inside this cell, the radon dissolved in water is transferred via diffusion into a closed counter-flow of air and subsequently detected by a radon-in-air monitor. Where the in-situ radon determination is concerned, a module composed of a semipermeable membrane is introduced into a water column. Subsequently, the radon dissolved in the water body diffuses through the membrane into the corresponding air flow, by means of which it is transferred into a radon-in-air monitor and is detected. Combination of the developed mobile radon extraction techniques with a suitable and portable radon monitor allow the detection of radon-222 with sufficient accuracy (smaller 20 %) in groundwater as well as in surface waters, i.e., within a broad range of concentrations. Radon-222 was subsequently used to characterize groundwater discharge into a meromictic and a dimictic lake, i.e. two types of lake basically distinct from each other with respect to their water circulation properties were investigated. The use of the noble gas isotope radon-222 as a geochemical tracer makes the application of on-site detection techniques possible and that this in turn permits a rapid, reliable, and cost-effective assessment of groundwater discharge rates into lake water bodies.

  12. Study of water quality and carbon absorbtion in West Sunter Lake using phytoplankton

    Science.gov (United States)

    Rusly, C. M.; Hendrawan, D.; Rinanti, A.

    2018-01-01

    The purposes of this research are to analyze the water quality and measure the carbon absorbtion in water of West Sunter Lake using the phytoplankton community. The sampling and analysis of water quality and phytoplankton using the APHA method. The result show that DO is 1.1-1.4 mg/L),BOD is 10.34 to 27.35 mg/L, COD is 23-130 mg/L, and phosphate is 0.38-0.57 mg/L. The range of index values were at 0,128 to 2,516 for the Diversity Index (H’), 0.003 to 0.924 for the Evenness Index (E), that is waters this medium polluted. The study indicated that the water quality and productivity of West Sunter Lake is impacted by the activities around West Sunter Lake, especially the household activities. The value of chlorophyll-a in the Reservoir was ranging from 3.2-386.9 mg/m3 or 0.89 s/d 105.52 mg C/m3 and carbon which absorbed by phytoplankton are 2×109 to 14×109 ton/year or 9×103 to 50×103 ton/m3. The amount of carbon absorbtion by phytoplankton per year proves that phytoplankton have an important role in reducing CO2 emissions.

  13. A STUDY OF RECOVERING A REED ECOSYSTEM USING POROUS CONCRETE IN THE LAKE BIWA SHORE

    Science.gov (United States)

    Takeda, Naho; Kato, Hayato; Okamoto, Takahisa; Kojima, Takayuki

    In this study, reed planting tests were carried out at the Biyo-center, an experiment station on the Lake Biwa shore, in order to evaluate the feasibility of a planting method with porous concrete (PoC method). Reed planting tests with coconut-fiber mats (mat method), which were generally used around Lake Biwa, were simultaneously carried out to compare with the PoC method. The reeds planted by the PoC method grew better than the ones planted by the mat method, and the number of reeds which were washed away by waves was smaller than that planted by the mat method. The result of the observation of reeds planted in the PoC showed plant maturation, and reeds could ta ke root into the PoC without interference with the voids of the PoC. As a result, it was shown that the reed planting tests with the PoC method was simple and effective, so it would become in harmony with the environment around Lake Biwa.

  14. FORMATION OF THE FOREST CENOSIS AT THE BOTTOM OF THE DRIED UP LAKES IN DRY STEPPE ZONE OF THE CHECHEN REPUBLIC

    Directory of Open Access Journals (Sweden)

    R. S. Erzhapova

    2012-01-01

    Full Text Available At the present time the lake Generalskiy completely went dry, water surface of the lake Maerskiy is a little more than 1 hectare. The bottom of the lake Generalskiy is completely overgrown by woody, shrubby and grassy vegetation. Was formed here biocenosis with their flora and fauna, which is a kind of «island of life» among the surrounding Sands. In the article the systematic list of the vegetation cover are given.

  15. Integrating Climate Change into Great Lakes Protection

    Science.gov (United States)

    Hedman, S.

    2012-12-01

    Climate change is now recognized as one of the greatest threats to the Great Lakes. Projected climate change impacts to the Great Lakes include increases in surface water and air temperature; decreases in ice cover; shorter winters, early spring, and longer summers; increased frequency of intense storms; more precipitation falling as rain in the winter; less snowfall; and variations in water levels, among other effects. Changing climate conditions may compromise efforts to protect and restore the Great Lakes ecosystem and may lead to irrevocable impacts on the physical, chemical, and biological integrity of the Great Lakes. Examples of such potential impacts include the transformation of coastal wetlands into terrestrial ecosystems; reduced fisheries; increased beach erosion; change in forest species composition as species migrate northward; potential increase in toxic substance concentrations; potential increases in the frequency and extent of algal blooms; degraded water quality; and a potential increase in invasive species. The Great Lakes Restoration Initiative, signed into law by President Obama in 2010, represents the commitment of the federal government to protect, restore, and maintain the Great Lakes ecosystem. The GLRI Action Plan, issued in February 2010, identifies five focus areas: - Toxic Substances and Areas of Concern - Invasive Species - Nearshore Health and Nonpoint Source Pollution - Habitat and Wildlife Protection and Restoration - Accountability, Education, Monitoring, Evaluation, Communication, and Partnerships The Action Plan recognizes that the projected impacts of climate change on the Great Lakes have implications across all focus areas and encourages incorporation of climate change considerations into GLRI projects and programs as appropriate. Under the GLRI, EPA has funded climate change-related work by states, tribes, federal agencies, academics and NGOs through competitive grants, state and tribal capacity grants, and Interagency

  16. The impact of a shade coffee certification program on forest conservation: a case study from a wild coffee forest in Ethiopia.

    Science.gov (United States)

    Takahashi, Ryo; Todo, Yasuyuki

    2013-11-30

    In recent years, shade coffee certification programs have attracted increasing attention from conservation and development organizations. Certification programs offer an opportunity to link environmental and economic goals by providing a premium price to producers and thereby contributing to forest conservation. However, the significance of the conservation efforts of certification programs remains unclear because of a lack of empirical evidence. The purpose of this study was to examine the impact of a shade coffee certification program on forest conservation. The study was conducted in the Belete-Gera Regional Forest Priority Area in Ethiopia, and remote sensing data of 2005 and 2010 were used to gauge the change of forest area. Using propensity score matching estimation, we found that forests under the coffee certification program were less likely to be deforested than forests without forest coffee. By contrast, the difference in the degree of deforestation between forests with forest coffee but not under the certification program and forests with no forest coffee is statistically insignificant. These results suggest that the certification program has had a large effect on forest protection, decreasing the probability of deforestation by 1.7 percentage points. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Hessian forest ecosystem study. Hessian forest ecosystem study 2004: Weather - water balance - gas concentrations; Waldoekosystemstudie Hessen. Waldzustandsbericht 2004: Witterung - Wasserhaushalt - Gaskonzentrationen

    Energy Technology Data Exchange (ETDEWEB)

    Paar, U.; Gawehn, P.; Scheler, B.; Schmidt, M.; Kolb, M.; Schoenfelder, E.; Eichhorn, J. (comps.) [Hessen-Forst, Hannoversch Muenden (Germany)

    2004-07-01

    The Hessian Forest Ecosystem Study aims to document and explore changes to forest ecosystems as a result of emissions and climatic influences. Thus, it contributes importantly to a multifunctional and sustainable forest management. 2003 has been an exceptional warm and dry year. High precipitation during summer 2004 reduced some of the drought induced risks. However, crown condition assessments proved an increase of defoliation, mainly regarding young and old beech. Deposition of sulfur and acid components has been on a low level in 2003/2004. Input of acidity and sulfur caused changes in forest soils, therefore a well balance liming is recommended. A further reduction of nitrogen input in Hessian forests and ozone content of ambient air is required. (orig.)

  18. Regional climate signal modified by local factors - multi core study records (Lake Czechowskie region, N Poland)

    Science.gov (United States)

    Zawiska, Izabela; Rzodkiewicz, Monika; Noryśkiewicz, Agnieszka; Kramkowski, Mateusz; Obremska, Milena; Ott, Florian; Plessen, Birgit; Tjallingii, Rik; Słowiński, Michał; Błaszkiewicz, Mirosław; Brauer, Achim

    2016-04-01

    Lake sediments can be utilized as valuable paleoclimate and environmental archives as they contain information of past changes. Multi-proxy analyses of sedimentary compartments (e.g. pollen, diatoms, Cladocera) reveal those changes. However, to decipher the spatial variability of past climate changes and to define the proxies suited for local and regional scale reconstructions archive comparisons are needed. Here we present a detailed multi-proxy study from four different sediment cores covering the Younger Dryas cold period from the Lake Czechowskie region (N Poland). Three cores are located along a transect in the Lake Czechowskie basin from its deepest point towards a former lake bay close to today's shoreline. The fourth lacustrine sediment core was retrieved from the Trzechowskie paleolake, app. 1 km W from Lake Czechowskie. The dataset comprises information from pollen (AP, NAP, Juniperus, Betula-tree, Pinus silvestris), diatom (planktonic/benthic index, diatom valve concentration, dominant species), Cladocera (planktonic/benthic index, dominant species, number of Cladocera species, total sum of specimens) and geochemical (TOC and CaCO3 content, mineral matter, titanium) analyses. At the beginning of the Younger Dryas the AP pollen share decreased and NAP and Juniperus pollen increased in all studied locations. The mineral matter and titanium record showed higher values in two cores taken from the deepest parts of Lake Czechowskie and the core from Trzechowskie paleolake while in the core located at the marginal part of the lake it was already high in Allerød and it did not change much in Younger Dryas. The Cladocera based indexes: total sum of specimens and number of species decreased at the beginning of YD but on the contrary the Cladocera species composition changes were site-specific. The diatoms valve concentration index significantly lowered in core from the deep location while on the contrary increased in core from paleolake Trzechowskie. Our results

  19. The assessment of land use change impact on watersheds runoff using SWAT: case study of Urmia Lake in Iran

    Science.gov (United States)

    Jabbari, Anahita; Jarihani, Ben; Rezaie, Hossein

    2015-04-01

    Lake Urmia, long counted among the world's largest saltwater lakes, contains only 5% of the amount of water it did just 20 years ago. The decline is generally blamed on a combination of drought, increased water diversion for irrigated agriculture within the lake's watershed and land use mismanagement. It has been believed that land use changes in Lake Urmia basin is one of the most important factors in shrinkage of Urmia Lake in recent decades. Transforming the traditional agricultural practices (i.e., wheat) to the more water consuming practices (i.e., apple orchards) is one of the most important reasons increased agricultural water consumption in the watershed. In this study we assessed the effect of the land use changes of watershed in hydrological runoff processing in the Nazloo chai watershed, one of the most important river basins of the Urmia Lake basin. Actually the rapid and at the same time unreasonable transformations of land use in farm lands of Urmia lake sub basins, extremely has been raised the amount of blue water (surface or groundwater) consumption in watershed which leads to dramatic decrement of watershed runoff amounts. One of the most unfavorable consequences of land use change was changing the blue and green (rainwater insofar as it does not become runoff) water usage patterns in watershed, in addition to water use increment. The soil and water assessment tool (SWAT), one of the most important and reliable models which was used to model the rainfall runoff, has been used in current study. The land use maps were extracted from Landsat images archives for the most severe turning points in respect of land use change in the recent 30 years. After calibrating the model, several land use patterns of historical data were used in the model to produce the runoff. The results showed the strong relation between land use change and runoff reduction in the Lake Urmia basin.

  20. Marine lake as in situ laboratory for studies of organic matter influence on speciation and distribution of trace metals

    Science.gov (United States)

    Mlakar, Marina; Fiket, Željka; Geček, Sunčana; Cukrov, Neven; Cuculić, Vlado

    2015-07-01

    Karst marine lakes are unique marine systems, also recognized as in situ "laboratories" in which geochemical processes on a different scale compared to the open sea, can be observed. In this study, organic matter cycle and its impact on distribution of trace metals in the marine lake Mir, located on Dugi Otok Island, in the central part of the eastern Adriatic Sea, was investigated for the first time. Studied marine lake is small, isolated, shallow basin, with limited communication with the open sea. Intense spatial and seasonal variations of organic matter, dissolved and particulate (DOC, POC), and dissolved trace metals concentrations in the water column of the Lake are governed predominantly by natural processes. Enhanced oxygen consumption in the Lake during summer season, high DOC and POC concentrations and low redox potential result in occasional occurrence of anoxic conditions in the bottom layers with appearance of sulfur species. Speciation modeling showed that dissolved trace metals Cu, Pb and Zn, are mostly bound to organic matter, while Cd, Co and Ni are present predominantly as free ions and inorganic complexes. Trace metals removal from the water column and their retention in the sediment was found to depend on the nature of the relationship between specific metal and organic or inorganic phases, sulfides, Fe-oxyhydroxydes or biogenic calcite. The above is reflected in the composition of the sediments, which are, in addition to influence of karstic background and bathymetry of the basin, significantly affected by accumulation of detritus at the bottom of the Lake.

  1. Three air quality studies: Great Lakes ozone formation and nitrogen dry deposition; and Tucson aerosol chemical characterization

    Science.gov (United States)

    Foley, Theresa

    The Clean Air Act of 1970 was promulgated after thousands of lives were lost in four catastrophic air pollution events. It authorized the establishment of National Ambient Air Quality Standards or (NAAQS) for six pollutants that are harmful to human health and welfare: carbon monoxide, lead, nitrogen dioxide, particulate matter, ozone and sulfur dioxide. The Clean Air Act also led to the establishment of the United Stated Environmental Protection Agency (US EPA) to set and enforce regulations. The first paper in this dissertation studies ozone in the Lake Michigan region (Foley, T., Betterton, E.A., Jacko, R., Hillery, J., 2011. Lake Michigan air quality: The 1994-2003 LADCO Aircraft Project (LAP). Atmospheric Environment 45, 3192-3202.) The Chicago-Milwaukee-Gary metropolitan area has been unable to meet the ozone NAAQS since the Clean Air Act was implemented. The Lake Michigan Air Directors' Consortium (LADCO) hypothesized that land breezes transport ozone precursor compounds over the lake, where a large air/water temperature difference creates a shallow conduction layer, which is an efficient reaction chamber for ozone formation. In the afternoon, lake breezes and prevailing synoptic winds then transport ozone back over the land. To further evaluate this hypothesis, LADCO sponsored the 1994-2003 LADCO Aircraft Project (LAP) to measure the air quality over Lake Michigan and the surrounding areas. This study has found that the LAP data supports this hypothesis of ozone formation, which has strong implications for ozone control strategies in the Lake Michigan region. The second paper is this dissertation (Foley, T., Betterton, E.A., Wolf, A.M.A., 2012. Ambient PM10 and metal concentrations measured in the Sunnyside Unified School District, Tucson, Arizona. Journal of the Arizona-Nevada Academy of Science, 43, 67-76) evaluated the airborne concentrations of PM10 (particulate matter with an aerodynamic diameter of 10 microns or less) and eight metalloids and metals

  2. Improving erosion modeling on forest roads in the Lake Tahoe Basin: Small plot rainfall simulations to determine saturated hydraulic conductivity and interrill erodibility

    Science.gov (United States)

    N. S. Copeland; R. B. Foltz

    2009-01-01

    Lake Tahoe is renowned for its beauty and exceptionally clear water. The Tahoe basin economy is dependent upon the protection of this beauty and the continued availability of recreational opportunities in the area; however, scientists estimate that the continued increase in fine sediment and nutrient transport to the lake threatens to diminish this clarity in as little...

  3. A National Probabilistic Study of Polybrominated Diphenyl Ethers in Fish from US Lakes and Reservoirs

    Science.gov (United States)

    National estimates were developed for polybrominated diphenyl ethers (PBDEs) in fish from lakes and reservoirs of the conterminous United States (excluding the Laurentian Great Lakes and Great Salt Lake) using an unequal probability design. Predator (fillet) and bottom-dweller (w...

  4. Final report of the AECL/SKB Cigar Lake analog study

    International Nuclear Information System (INIS)

    Cramer, J.

    1994-05-01

    The Cigar Lake uranium deposit is located in northern Saskatchewan, Canada. The 1.3-billion-year-old deposit is located at a depth of about 450 m below surface in a water-saturated sandstone at the unconformity contact with the high-grade metamorphic rocks of the Canadian Shield. The Cigar Lake deposit has many features that parallel those being considered within the Canadian concept for disposal of nuclear fuel waste. The study of these natural structures and processes provides valuable insight toward the eventual design and site selection of a nuclear fuel waste repository. The main feature of this analog is the absence of any indication on the surface of the rich uranium ore 450 m below. This indicates that the combination of natural barriers has been effective in isolating the uranium ore from the surface environment. More specifically, the deposit provides analog information relevant to the stability of UO 2 fuel waste, the performance of clay-based barriers, radionuclide migration, colloid formation, radiolysis, fission-product geochemistry and general aspects of water-rock interaction. The main geochemical studies on this deposit focus on the evolution of groundwater compositions in the deposit and on their redox chemistry with respect to the uranium, iron and sulphide systems. Since 1984, through cooperation from the owners of the Cigar Lake deposit, analog studies have been conducted. AECL, with support from Ontario Hydro under the auspices of the CANDU Owners Group, initiated international participation in 1989 through collaboration with the Swedish Nuclear Fuel and Waste Management Company (SKB) and, more recently, with the Los Alamos National Laboratory (LANL). This report gives the results of the various studies carried out during the 3-year collaboration between AECL and SKB, as well as a summery of the LANL study. It provides detailed information on the generated databases and models, and integrates this information into conclusions for use in safety

  5. Selecting the Best Band Ratio to Estimate Chlorophyll-a Concentration in a Tropical Freshwater Lake Using Sentinel 2A Images from a Case Study of Lake Ba Be (Northern Vietnam

    Directory of Open Access Journals (Sweden)

    Nguyen Thi Thu Ha

    2017-09-01

    Full Text Available This study aims to develop a method to estimate chlorophyll-a concentration (Chla in tropical freshwater lake waters using in situ data of Chla, water reflectance, and concurrent Sentinel 2A MSI imagery (S2A over Lake Ba Be, a Ramsar site and the largest natural freshwater lake in Vietnam. Data from 30 surveyed sampling sites over the lake water in June 2016 and May 2017 demonstrated the appropriateness of S2A green-red band ratio (band 3 versus band 4 for estimating Chla. This was shown through a strong correlation of corresponded field measured reflectance ratio with Chla by an exponential curve (r2 = 0.68; the mean standard error of the estimates corresponding to 5% of the mean value of in situ Chla. The small error between in situ Chla, and estimated Chla from S2A acquired concurrently, confirmed the S2A green-red band ratio as the most suitable option for monitoring Chla in Lake Ba Be water. Resultant Chla distribution maps over time described a partially-seasonal pattern and also displayed the spatial dynamic of Chla in the lake. This allows a better understanding of the lake’s limnological processes to be developed and provides an insight into the factors that affect lake water quality. The results also confirmed the potential of S2A to be used as a free tool for lake monitoring and research due to high spatial resolution data (10 m pixel size.

  6. A study on the utilization of forest policy to review from the aspect of climate change

    Science.gov (United States)

    Ardhana, I. Putu Gede

    2017-11-01

    The purpose of this study was to review the utilization of forests from the policy aspects of climate change. This was then associated with the implementation of governmental commitment to carry out REDD+ to cope with the impact of climate change and to achieve sustainable development. Firstly, the author studied this problem from data and information about vast forest areas and conservative water areas in Indonesia. According to provincial governments, there have been several decision letters from the Minister of Forestry from different years ranging from 1999-2014. Comparing the forest areas in letters of 2005, 2008, and 2015, it can be suggested that the areas allocated as productive forest exceeded the areas of conserved or protected forest. This indicates that the utilization of forest as a development resource has occurred, and will continue to become an important element in Indonesia. Furthermore, Indonesian forests continue to suffer deforestation and forest degradation. Therefore, the author presented data and information about deforestation and forest degradation that occurred from forest damage and forest fires. Thirdly, the author presented data and information about the deforestation rate from 2000-2014. In 1989, rehabilitation activities were carried out for critical lands, and from 2012-2014, rehabilitation of forest and riverside areas occurred. This research uses descriptive methods with an approximation of legislation and an approach to librarianship. Then, this study is described in a narrative as well as an interpretive style, and compiled in the form of a working paper. From the results of this research, it can be concluded that Indonesian governmental policy regarding forest utilization has wide potential mitigations, and it is absolutely necessary to consistently implement a number of such programs related to climate change.

  7. Final report of the AECL/SKB Cigar Lake analog study

    International Nuclear Information System (INIS)

    Cramer, J.J.

    1994-07-01

    The Cigar Lake uranium deposit is located in northern Saskatchewan, Canada. The 1.3-billion-year-old deposit is located at a depth of about 450 m below surface in a water-saturated sandstone at the unconformity contact with the high-grade metamorphic rocks of the Canadian Shield. The uranium mineralization, consisting primarily of uraninite (UO 2 ), is surrounded by a clay-rich halo in both sandstone and basement rocks, and remains extremely well preserved and intact. The average grade of the mineralization is ∼ 8 wt.% U; locally grades are as high as ∼ 55 wt.%U. The Cigar lake deposit has many features that parallel those being considered within the Canadian concept for disposal of nuclear fuel waste. Specifically, the deposit provides analog information relevant to the stability of UO 2 fuel waste, the performance of clay-based barriers, radionuclide migration, colloid formation, radiolysis, fission-product geochemistry and general aspects of water-rock interaction. The main geochemical studies on this deposit focus on the evolution of groundwater compositions in the deposit and on their redox chemistry with respect to the uranium, iron and sulphide systems. Since 1984, through cooperation from the owners of the Cigar lake deposit, analog studies have been conducted. AECL, with support from Ontario Hydro under the auspices of the CANDU Owners Group, initiated international participation in 1989 through collaboration with the Swedish Nuclear Fuel and Waste Management Company (SKB) and, more recently, with the Los Alamos National Laboratory (LANL). This report gives the results of the various studies carried out during the 3-year collaboration between AECL and SKB, as well as a summary of the LANL study. It provides detailed information on the generated databases and models, and integrates this information into conclusions for use in safety assessment of the Canadian, Swedish and United States disposal concepts. 15 refs., 25 figs., 55 tabs

  8. Using radon-222 for tracing groundwater discharge into an open-pit lignite mining lake--a case study.

    Science.gov (United States)

    Schmidt, Axel; Schubert, Michael

    2007-12-01

    Groundwater discharge into an open pit lignite mining lake was investigated using radon-222 as a naturally occurring environmental tracer. The chosen study site was a meromictic lake, i.e., a water body that is divided horizontally into two separate layers--the upper mixolimnion (with seasonal mixing) and the lower monimolimnion (without seasonal mixing). For the estimation of groundwater discharge rates into the lake, a simple box model including all radon sinks and sources related to each layer was applied. Two field investigations were performed. During the October campaign, the total groundwater discharge into the lake was found to be 18.9 and 0.7 m(3) d(-1) for the mixolimnion and monimolimnion, respectively. During the December campaign, the groundwater discharge into the mixolimnion was 15.0 m(3) d(-1), whereas no discharge at all was observed into the monimolimnion. Based on the given water volumes, the residence time of lake water was 5.3 years for the monimolimnion and varies between 0.9 and 1.1 years for the mixolimnion. The investigation confirmed radon to be a useful environmental tracer for groundwater and surface water interactions in meromictic lake environments.

  9. Progress in study of Prespa Lake using nuclear and related techniques (IAEA Regional Project RER/8/008)

    International Nuclear Information System (INIS)

    Anovski, Todor

    2001-09-01

    One of the main objective of the IAEA - Regional project RER/8/008 entitled Study of Prespa Lake Using Nuclear and Related Techniques was to provide a scientific basis for sustainable and environmental management of the Lake Prespa (Three lakes: Ohrid, Big Prespa and Small Prespa are on the borders between Albania, Republic of Macedonia and Greece, and are separated by the Mali i Thate and Galichica, mostly Carstificated mountains), see Fig. 1. In this sense investigations connected with the hydrogeology, water quality (Physics-chemical, biological and radiological characteristics) and water balance determination by application of Environmental isotopes ( i.e. H,D,T,O-18,O-18 etc.,) distribution, artificial water tracers and other relevant analytical techniques such as: AAS, HPLC, Total α and β-activity, α and γ-spectrometry as well as ultra sonic measurements (defining of the Lake bottom profile) through regional cooperation / Scientists from Albania, Greece and Republic of Macedonia, participated in the implementation of the Project/ during one hydrological year, had been initiated and valuable results obtained, a part of which are presented in this report. This cooperation was the only way for providing necessary data for better understanding beside the other, of the water quality of the Prespa Lake and its hydrological relationship to Ohrid Lake too, representing a unique regional hydro system in the world. (Author)

  10. Changes in lake level and trophy at Lake Vrana, a large karstic lake on the Island of Cres (Croatia, with respect to palaeoclimate and anthropogenic impacts during the last approx. 16,000 years

    Directory of Open Access Journals (Sweden)

    Ante BARIĆ

    2000-08-01

    Full Text Available A multi-proxy approach study (cladocerans, diatoms, geochemistry, plant macrofossils, pollen, was performed on a sediment core from Lake Vrana (Vransko Jezero, a large and deep karstic lake on the northern Adriatic island of Cres, Croatia. Considerable lake-level changes occurred during the last approx. 16,000 years. The stratigraphic evidence suggests that periods of enhanced precipitation and the post-LGM rise in sea level were the main driving forces. The lake records indicate early human impacts. Sediment echo-sounding indicated that >25 m of lake sediments lies within the site, from which 5 m have been cored. Shallow lake stages occurred from 14.4 14C ky BP to early Holocene. Prior to Alleröd, interglacial sediments were redeposited, reflecting the influences of rising sea-level (forming a local groundwater barrier, a temporary increase in precipitation, and lake-level changes. There appears to be a hiatus in the sequence, for no sediments assignable to the Alleröd chronozone could be found. A discordance in the echo profile at the appropriate horizon in the sequence supports this interpretation. Groundwater level increased again at 10.6 ky BP (during Younger Dryas chronozone, a swamp vegetation formed, which gave way to a shallow lake. During the Preboreal chronozone, this freshwater lake persisted with fluctuating levels. The establishment and subsequent persistence of the present deep water lake at about 8.5 ky BP, correspond with findings of a pluvial period at the Dalmatian coast, which lasted from 8.4 to 6 ky BP. First human catchment disturbances were related to settlements of Neolithic or Bronze Age. The increase in summer drought, coupled with forest clearance during Illyrian times, are assumed to be responsible for the change towards present evergreen oak vegetation in the lake catchment. The intensification in land-use during Roman and post-Roman settlements caused a slight increase in the lake trophic level.

  11. Analysis of stand basal area development of thinned and unthinned Acer rubrum forests in the upper Great Lakes region, USA

    Science.gov (United States)

    Justin L. Pszwaro; Anthony W. D' Amato; Thomas E. Burk; Matthew B. Russell; Brian J. Palik; Terry F. Strong

    2016-01-01

    Red maple (Acer rubrum L.), historically a common but not abundant tree species in North America, has increased in abundance throughout its range over the last several decades; however, it has received little attention in growth and yield studies. The objectives of this study were to (i) evaluate the effects of stocking level and stand density on...

  12. Late-Holocene climate variability in southern New Zealand: A multi-proxy study of lake sediments from Lake Ohau to reconstruct regional climate

    Science.gov (United States)

    Roop, H. A.; Vandergoes, M. J.; Levy, R. H.; Dunbar, G.; Upton, P.; Stumpner, P.; Fitzsimons, S.; Howarth, J. D.; Ditchburn, R.; Wilson, G. S.; Purdie, J.

    2012-12-01

    Driving this research is the need to improve understanding of synoptic climate systems influencing climate in southern New Zealand and to document changes in the character of these systems beyond the historical record. Inter-annual variability of New Zealand's climate (e.g. temperature and precipitation) is influenced by large-scale patterns originating in both the tropics (El-Niño-Southern Oscillation, Interdecadal Pacific Oscillation) and the Antarctic (Southern Annular Mode). Currently, very few highly resolved climate reconstructions exist in mid-latitudes of the Southern Hemisphere. The identification of annually laminated sediments in Lake Ohau, Mackenzie Basin, New Zealand (44.234°S, 169.854°E) offers a unique opportunity to investigate changes in regional hydrology and climate, and by extension also explore connections to large-scale climate patterns. Importantly, Lake Ohau is situated east of and in the lee of the Southern Alps, rendering the region characteristically dry and sensitive to small fluctuations in precipitation and temperature. Short cores (<6 meters) from Lake Ohau contain layered sedimentary couplets, which 137Cs and 210Pb analyses suggest represent annual accumulation of terrigenous sediment at an average rate of 0.5 cm a-1. Core imaging (RGB, L*), density, and magnetic susceptibility data were acquired using a GeoTek multi-sensor core logger. Here we present an initial assessment of couplet characteristics based on thin-sections, grain size analysis, and GeoTek output. Extensive limnological monitoring, including acoustic Doppler profilers, thermister strings, sediment traps, and turbidity meters will help to further develop a detailed understanding of processes driving seasonal sediment deposition in Lake Ohau. These limnological data, and preliminary correlations with lake inflow data (1924-2012), and local precipitation and temperature data (1910-2012) will also be presented. This work provides the foundation for reconstructing the

  13. A method of selecting forest sites for air pollution study

    Science.gov (United States)

    Sreedevi K. Bringi; Thomas A. Seliga; Leon S. Dochinger

    1981-01-01

    Presents a method of selecting suitable forested areas for meaningful assessments of air pollution effects. The approach is based on the premise that environmental influences can significantly affect the forest-air pollution relationship, and that it is, therefore, desirable to equalize such influences at different sites. From existing data on environmental factors and...

  14. Ecological studies on rain forest in Northern Suriname

    NARCIS (Netherlands)

    Schulz, J.P.

    1960-01-01

    During the years 1955-1957 ecological data were collected in various types of mesophytic forest occurring in the northern half of central Suriname (fig. 1). Physiognomically as well as floristically these forests correspond with the type of vegetation which in the other parts of tropical America

  15. Cyanobacteria Dominance in Lakes and Evaluation of Its Predictors: a Study of Southern Appalachians Ecoregion, USA

    OpenAIRE

    Ghaffar Sajeela; Stevenson R. Jan; Khan Zahiruddin

    2016-01-01

    Owing to their ecological and economic implications, the abundance of cyanobacteria has been an important subject in aquatic ecology. There has been a debate about which nutrients are a better predictor of cyanobacteria abundance, total nitrogen (TN), total phosphorus (TP) or nitrogen to phosphorus ratio (N:P). A classic study by Downing and coworkers in 2001 concluded that total N and total P are better predictors than TN:TP ratio. We picked lakes from a different region of the US, the South...

  16. DOE Zero Energy Ready Home Case Study: Healthy Efficient Homes - Spirit Lake, Iowa

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-11-01

    This case study describes a DOE Zero Energy Ready Home in Spirit Lake, Iowa, that scored HERS 41 without PV and HERS 28 with PV. This 3,048 ft2 custom home has advanced framed walls filled with 1.5 inches closed-cell spray foam, a vented attic with spray foam-sealed top plates and blown fiberglass over the ceiling deck. R-23 basement walls are ICF plus two 2-inch layers of EPS. The house also has a mini-split heat pump, fresh air fan intake, and a solar hot water heater.

  17. The Socio-hydrology of Bangalore's Lake System and implications for Urban Water Security

    Science.gov (United States)

    Srinivasan, V.; Roy, S.

    2017-12-01

    Bengaluru city has experienced unprecedented growth in recent decades. If the city is to sustain growth and claim its position as a "global" high-tech city, it must be able to secure sufficient water supply and also create a healthy livable environment. With the city's many lakes vanishing due to rapid urbanisation, depletion of groundwater as a result of overuse in the peri-urban areas, and lack of proper underground drainage system and sewage treatment plants, Bangalore is now grappling with issues of imminent water crisis, inequitable access to water supply, and public health hazards. In this context, the restoration of Bangalore's lakes has been promoted as a panacea for its flooding, water stress, and wastewater problems. It has been argued that lakes can store storm water and recycled wastewater and avoid the need for potentially destructive, expensive schemes that may destroy biodiversity rich aquatic ecosystems and forests. Bangalore's lakes are linked by the drainage channels to form a cascade; overflow from each lake flows to the next lake downstream. Yet, most efforts have tended to view the lakes in isolation. This study of the hydrology of Bangalore's lake system in its entirety simulates the lake system as a whole. The study explores approaches to management and theor impact on urban water security.

  18. Analysis of the Mechanism Hindering Sustainable Forestry Operations: A Case Study of Japanese Forest Management

    Directory of Open Access Journals (Sweden)

    Yukari Fuchigami

    2016-08-01

    Full Text Available We investigated local forest management practices in Osaka, Japan aiming to clarify mechanisms that hinder long-term, sustainable forestry operation by carrying out forest surveys and interview surveys. Because mountain districts in Japan now face declining and aging populations, forestry work has shifted to forest owners’ associations, with efficient forest management being required on an ad hoc basis as a result of the subsidy system. We found that the forest management plan for the study site utilized only one-seventh of the economic value of the forest, mainly due to the local forestry structure and an inefficient subsidy system that requires efficiency. The income yielded by timber undergoing such forest management and distribution processes is too low to permit forest owners to carry out sufficient forest cultivation. To effectively utilize the wood, a subsidy system that takes a long-term view and a timber market that puts an appropriate price on wood are needed. We argue that it is important to bolster the management position of the Japanese Forest Owners’ Associations for design an institutional scheme that enables to practice forestry management from a long-term perspective.

  19. Salting our freshwater lakes

    Science.gov (United States)

    Bartlett, Sarah L.; Burke, Samantha M.; Doubek, Jonathan P.; Krivak-Tetley, Flora E.; Skaff, Nicholas K.; Summers, Jamie C.; Farrell, Kaitlin J.; McCullough, Ian M.; Morales-Williams, Ana M.; Roberts, Derek C.; Ouyang, Zutao; Scordo, Facundo; Hanson, Paul C.; Weathers, Kathleen C.

    2017-01-01

    The highest densities of lakes on Earth are in north temperate ecosystems, where increasing urbanization and associated chloride runoff can salinize freshwaters and threaten lake water quality and the many ecosystem services lakes provide. However, the extent to which lake salinity may be changing at broad spatial scales remains unknown, leading us to first identify spatial patterns and then investigate the drivers of these patterns. Significant decadal trends in lake salinization were identified using a dataset of long-term chloride concentrations from 371 North American lakes. Landscape and climate metrics calculated for each site demonstrated that impervious land cover was a strong predictor of chloride trends in Northeast and Midwest North American lakes. As little as 1% impervious land cover surrounding a lake increased the likelihood of long-term salinization. Considering that 27% of large lakes in the United States have >1% impervious land cover around their perimeters, the potential for steady and long-term salinization of these aquatic systems is high. This study predicts that many lakes will exceed the aquatic life threshold criterion for chronic chloride exposure (230 mg L−1), stipulated by the US Environmental Protection Agency (EPA), in the next 50 y if current trends continue. PMID:28396392

  20. Lake ecosystem response to climate change 8200 years ago. A multi-proxy study at Lake Højby Sø, Denmark

    DEFF Research Database (Denmark)

    Rasmussen, Peter; Hede, Mikkel Ulfeldt; Noe-Nygaard, Nanna

    2009-01-01

    of climate and the effects of human activities. These problems also complicate the prediction of possible future climate influence on lake ecology. A way of circumventing these problems is the use of lake sediment records which contain a wealth of information about past lake history over long time scales...

  1. Working woods: A case study of sustainable forest management on Vermont family forests

    Science.gov (United States)

    Neal F. Maker; Rene H. Germain; Nathaniel M. Anderson

    2014-01-01

    Families own 35% of US forestland and 67% of Vermont forestland. Sustainable management of their woodlots could provide social and economic benefits for generations. We examined sustainable forest management across four counties in Vermont by evaluating the use of silvicultural practices and best management practices on 59 recently harvested, family-owned properties...

  2. A study of the dry forest communities in the Dominican Republic

    Directory of Open Access Journals (Sweden)

    Antonio García-Fuentes

    2015-03-01

    Full Text Available This paper is a floristic and phytosociological study of the dry forest communities of the Dominican Republic. A total of 69 relevés in dry forest biotopes were carried out. The samples were subsequently subjected to Detrended Correspondence Analysis for the determination and study of possible groupings. The study does not cover tree formations growing on serpentines, nor the so-called semideciduous forests, peculiar to areas with higher rainfall. A total of nine phytocoenoses were identified. The most significant results led to the description of six new phytosociological associations: Simaroubetum berteroani(thorny dry forest on coastal dunes, Phyllostylo rhamnoidis-Prosopidetum juliflorae (southern Dominican disturbed dry forest, Consoleo moniliformis-Camerarietum linearifoliae(dry forest on hard limestones, Lemaireocereo hystricis-Prosopidetum juliflorae(northern Dominican disturbed dry forest, Lycio americani-Prosopidetum juliflorae (disturbed dry forest on saline soils and Guettardo ellipticae-Guapiretum discoloris (dry forest on flat-topped hillocks in Montecristi. This is an important step forward in the phytosociological and floristic studies of the Caribbean territories.

  3. Late Quaternary lake-level changes constrained by radiocarbon and stable isotope studies on sediment cores from Lake Titicaca, South America

    Science.gov (United States)

    Rowe, Harold D.; Guilderson, Thomas P.; Dunbar, Robert B.; Southon, John R.; Seltzer, Geoffrey O.; Mucciarone, David A.; Fritz, Sherilyn C.; Baker, Paul A.

    2003-09-01

    developed for the Lake Titicaca sequence using different organic fractions, mobile organic sub-fractions and fractions containing mobile sub-fractions should generally be avoided in geochronology studies. Consequently, we believe humin and/or bulk decalcified ages provide the most consistent chronologies for the post-13,500 yr BP interval, and humin ages provide the most representative ages for sedimentation prior to 13,500 yr BP interval. Using the age model derived from the deep water core site and a previously published isotope-based lake-level reconstruction, we present a qualitative record of lake level in the context of several ice-core records from the western hemisphere. We find the latest Pleistocene lake-level response to changing insolation began during or just prior to the Bølling/Allerød period. Using the isotope-based lake-level reconstruction, we also find the 85-m drop in lake level that occurred during the mid-Holocene was synchronous with an increase in the variability of ice-core δ18O from a nearby icecap, but was not reflected in any of the polar ice-core records recovered from the interior of Antarctica and Greenland.

  4. Studies on the impact of local folk on forests of Garhwal Himalaya: Pt. 1

    International Nuclear Information System (INIS)

    Negi, A.K.; Todaria, N.P.

    1993-01-01

    People in the Himalayas have been using fuelwood as the only source of energy for generations. Increasing population and declining forest resources have led to strict environmental laws in the area. The human impact on forests of the region was studied. The present biomass consumption of approximate 442 kg person -1 yr -1 along with cowdung are contributing factors for the present state of forest deforestation in the region. (author)

  5. [Studies on nitrogen, phosphorus and organic matter in ponds around Chaohu Lake].

    Science.gov (United States)

    Sun, Qing-ye; Ma, Xiu-ling; Yang, Gui-de; Chen, Zheng; Wu, Hong-lin; Xuan, Huai-xiang

    2010-07-01

    There are a lot of ponds around Chaohu Lake. According to location and runoff supply of ponds, the ponds are divided into three types: ponds inner vellage (PIV), ponds adjacent vellage (PAV) and ponds outer vellage (POV). The samples of water and sediment were collected from 136 ponds around Chaohu Lake and the contents of nitrogen, phosphorus and organic matter in water and sediments were analyzed in this study. The results showed that mean contents of total nitrogen (TN), NH4+ -N, NO3- -N, NO2- -N, total phosphorus (TP), soluble PO4(3-) -P and COD were 2.53, 0.65, 0.18, 0.02, 0.97, 0.38 and 51.58 mg x L(-1) in pond water, respectively; and mean contents of TN, NH4+ -N, NO3- -N, NO2- -N, TP, inorganic phosphorus (IP), organic phosphorus (OP) and loss of ignition (LOI) in pond sediment were 1575.36, 35.73, 13.30, 2.88, 933.19, 490.14, 414.75 mg x kg(-1) and 5.44%, respectively. The ponds of more than 90% presented eutrophication in the contents of total nitrogen and phosphorus in water. The contents of TN and NH4+ -N in water and sediment of PIV were significantly higher than that of POV. And the contents of inorganic nitrogen in pond water and sediment displayed a following order: NH4+ -N > NO3- -N > NO2- -N. Data analysis indicated that there was a significantly positive correlation between organic matter and total nitrogen and phosphorus in water and sediment. The nitrogen, phosphorus and organic matter in ponds mainly sourced farmlands and village land surface. The contents of nitrogen, phosphorus and organic matter in ponds were affected by location and runoff supply of ponds. By retaining nitrogen, phosphorus and organic matter in runoff, the ponds can effectively decrease nutrient content into Chaohu Lake.

  6. Five hydrologic studies conducted by or in cooperation with the Center for Forested Wetlands Research

    Science.gov (United States)

    Devendra M. Amatya; Carl C. Trettin; R. Wayne Skaggs; T.J. Callahan; Ge Sun; J.E. Nettles; J.E. Parsons; M. Miwa

    2005-01-01

    The U.S. Department of Agriculture Forest Service Center for Forested Wetlands Research has conducted or cooperated in studies designed to improve understanding of fundamental hydrologic and biogeochemical processes that link aquatic and terrestrial ecosystems. Five of these studies are discussed here. The first is based on observations made on long-term experimental...

  7. Total Energy Recovery System for Agribusiness: Lake County study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Fogleman, S.F.; Fisher, L.A.; Black, A.R.

    1978-04-01

    A brief summary is given of the results of a previously reported study designed to evaluate the costs and viability of combined thermodynamic and biologic cycles in a system known as the Total Energy Recovery System for Agribusiness (TERSA). This conceptual system involved the combined geothermally assisted activities of greenhouse crop and mushroom growing, fish farming, and biogas generation in an integrated biologic system such that the waste or by-products of each subsystem cycle were recovered to service input needs of companion cycles. An updated direct use geothermal system based on TERSA that is viable for implementation in Lake County is presented. Particular consideration is given to: location of geothermal resources, availability of land and irrigation quality water, compatibility of the specific direct use geothermal activities with adjacent and local uses. Private interest and opposition, and institutional factors as identified. Factors relevant to local TERSA implementation are discussed, followed by sites considered, selection criteria, site slection, and the modified system resulting. Particular attention is paid to attempt to make clear the process followed in applying this conceptual design to the specific task of realistic local implementation. Previous publications on geothermal energy and Lake County are referenced where specific details outside the scope of this study may be found. (JGB)

  8. Preliminary juvenile Lost River and shortnose sucker investigations in Clear Lake, California--2011 pilot study summary

    Science.gov (United States)

    Burdick, Summer M.; Rasmussen, Josh

    2012-01-01

    Poor recruitment appears to limit the recovery of Lost River and shortnose sucker populations in Clear Lake Reservoir, California, but the cause is unknown. Adult suckers migrate up Willow Creek and its tributaries to spawn in some years, but low flow in Willow Creek may inhibit spawning migrations in other years. It is unclear whether spawning is successful, larvae survive, or juveniles persist to adulthood. Environmental variables associated with successful spawning or young-of-year survival have not been identified and early life history for these populations is poorly understood. The U.S. Geological Survey in cooperation with the U.S. Fish and Wildlife Service and Ruby Pipeline L.L.C. Corporation (El Paso, Tex.) initiated a study in 2011 to better understand juvenile sucker life history in Clear Lake Reservoir, and to identify constraints in the early life history that may limit recruitment to the adult spawning populations. This is a report on the 2011 pilot study for this project.

  9. Response of Termite (Blattodea: Termitoidae) Assemblages to Lower Subtropical Forest Succession: A Case Study in Dinghushan Biosphere Reserve, China.

    Science.gov (United States)

    Li, Zhi-Qiang; Ke, Yun-Ling; Zeng, Wen-Hui; Zhang, Shi-Jun; Wu, Wen-Jing

    2016-02-01

    Termite (Blattodea: Termitoidae) assemblages have important ecological functions and vary in structure between habitats, but have not been studied in lower subtropical forests. To examine whether differences in the richness and relative abundance of termite species and functional groups occur in lower subtropical regions, termite assemblages were sampled in Dinghushan Biosphere Reserve, China, among pine forest, pine and broad-leaved mixed forest (mixed forest), and monsoon evergreen broad-leaved forest (monsoon forest). The dominant functional group was wood-feeding termites (family Termitidae), and the mixed forest hosted the greatest richness and relative abundance. Soil-feeding termites were absent from the lower subtropical system, while humus-feeding termites were sporadically distributed in mixed forest and monsoon forest. The species richness and functional group abundance of termites in our site may be linked to the forest succession. Altitude, soil temperature, air temperature, surface air relative humidity, and litter depth were significant influences on species and functional group diversity.

  10. Water and chemical budgets of gravel pit lakes : Case studies of fluvial gravel pit lakes along the Meuse River (The Netherlands) and coastal gravel pit lakes along the Adriatic Sea (Ravenna, Italy)

    NARCIS (Netherlands)

    Mollema, P.N.

    2016-01-01

    Gravel pit lakes form when gravel is excavated from below the water table of a phreatic or shallow confined aquifer. Typically many of these lakes are concentrated along naturally occurring sedimentary gravel deposits in areas where gravel is needed for construction. Most gravel pit lakes are

  11. Assessment of factors limiting algal growth in acidic pit lakes--a case study from Western Australia, Australia.

    Science.gov (United States)

    Kumar, R Naresh; McCullough, Clint D; Lund, Mark A; Larranaga, Santiago A

    2016-03-01

    Open-cut mining operations can form pit lakes on mine closure. These new water bodies typically have low nutrient concentrations and may have acidic and metal-contaminated waters from acid mine drainage (AMD) causing low algal biomass and algal biodiversity. A preliminary study was carried out on an acidic coal pit lake, Lake Kepwari, in Western Australia to determine which factors limited algal biomass. Water quality was monitored to obtain baseline data. pH ranged between 3.7 and 4.1, and solute concentrations were slightly elevated to levels of brackish water. Concentrations of N were highly relative to natural lakes, although concentrations of FRP (<0.01 mg/L) and C (total C 0.7-3.7 and DOC 0.7-3.5 mg/L) were very low, and as a result, algal growth was also extremely low. Microcosm experiment was conducted to test the hypothesis that nutrient enrichment will be able to stimulate algal growth regardless of water quality. Microcosms of Lake Kepwari water were amended with N, P and C nutrients with and without sediment. Nutrient amendments under microcosm conditions could not show any significant phytoplankton growth but was able to promote benthic algal growth. P amendments without sediment showed a statistically higher mean algal biomass concentration than controls or microcosms amended with phosphorus but with sediment did. Results indicated that algal biomass in acidic pit lake (Lake Kepwari) may be limited primarily by low nutrient concentrations (especially phosphorus) and not by low pH or elevated metal concentrations. Furthermore, sediment processes may also reduce the nutrient availability.

  12. Functional microbiology of soda lakes

    NARCIS (Netherlands)

    Sorokin, D.Y.; Banciu, H.L.; Muyzer, G.

    2015-01-01

    Soda lakes represent unique permanently haloalkaline system. Despite the harsh conditions, they are inhabited by abundant, mostly prokaryotic, microbial communities. This review summarizes results of studies of main functional groups of the soda lake prokaryotes responsible for carbon, nitrogen and

  13. The integrated forest study on effects of atmospheric deposition; A status report

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D.W.; Lindberg, S.E.; Bondietti, E.A. (Oak Ridge National Lab., TN (USA)); Cole, D.W. (Washington Univ., Seattle, WA (USA)); Lovett, G.M. (Cary Aboretum, Millbrook, NY (US)); Mitchell, M. (State Univ. of New York, Syracuse, NY (USA)); Ragsdale, L.H. (Emory Univ., Atlanta, GA (USA))

    1987-01-01

    The principal objective of the Integrated Forest Study on Effects of Atmospheric Deposition is to determine the effects of atmospheric deposition at sulfur and nitrogen on forest nutrient cycling. The study integrates a field monitoring component, involving quantification of atmospheric deposition and nutrient cycling in a variety of forest sites, and experimental research, including laboratory and field studies to investigate selected atmospheric and soil processes in great detail. The research is being conducted at forested sites in the northwestern, northeastern, and southeastern United States and in Norway. The sites selected for this study represent a range of conditions in climate, air quality, soils, and vegetation, which will facilitate testing hypotheses about the effects of atmospheric sulfur and nitrogen deposition on forest nutrient cycles. Preliminary results show a wide range in atmospheric sulfur and nitrogen deposition and in ecosystem responses to such deposition, some of which are consistent with previous predictions.

  14. Species diversity and ecological studies Euglenophyta in the Zayandeh Rood lake dam

    Directory of Open Access Journals (Sweden)

    Masoumeh Shams

    2010-07-01

    Full Text Available Zayandeh Rood Lake, as the largest Isfahan natural Lake, is located in the west of Isfahan city with the area of about 48 km2. Sampling of Euglenophyta was done in four stations from August 2005 through June 2006. Ecological factors such as pH, EC, salinity, temperature and various nutrients were measured. A total of 4 genus and 9 species were identified in this lake. Euglena proxima Dang., Phacus caudatus var. ovalis Drez. and Trachelomonas robusta Swir., showed high density 1420, 952, 2380 cell/cm3, respectively. In this lake density of Euglenophyta increased in warm seasons because of high ions such as nitrate and phosphate. Based upon algal flora results, Zayandeh Rood dam lake could be regarded as an oligo-mesotrophic lake.

  15. A radioanalytical study of radionuclides in a dysoligotrophic lake in Southern Sweden

    International Nuclear Information System (INIS)

    Eriksson, M.; Roos, P.; Holm, E.; Peck, G.

    1998-01-01

    Unusually high activity concentration of various artificial radionuclides (from nuclear test fallout and the Chernobyl accident) and some natural radionuclides, have been discovered in lakes with high amounts of humic substances. These lakes tend to have low pH, at times down to pH 5. The lake, Svartsjoen, in the southern part of Sweden is one of these lakes. The food chain and resulting concentration factors in Svartsjoen were investigated and compared to results for other 'normal' lakes. Fish and water samples were collected and analysed for 137 Cs 239+240 Pu, 241 Am and 210 Po during a 4-month visit to Lund. The level of 239/240 Pu in the water of Svartsjoen was found to be elevated. The work on fish from the lake indicates that these elevated levels are not transferred into the food chain. It appears that the humic substances could be blocking plutonium from entering the food chain

  16. Bird mortality during nocturnal migration over Lake Michigan: A case study

    Science.gov (United States)

    Diehl, Robert H.; Bates, John M.; Willard, David E.; Gnoske, Thomas P.

    2014-01-01

    Millions of birds die each year during migration. Most of this mortality goes unobserved and conditions surrounding the actual events are often not thoroughly documented. We present a case study of substantial migrant casualties along the shores of southwestern Lake Michigan during May 1996 when we found 2,981 dead birds of 114 species, mostly migrant passerines. An unusual sequence of events allowed us to document the circumstances surrounding this migratory bird kill. Bird carcasses appeared on the southwestern shores of Lake Michigan in the days following storm systems that produced high rain and in one case, hail. Encounters between birds and precipitation over open water were recorded by weather radar, and were followed by winds that drifted dead birds toward highly populated shorelines where the kill was observed and documented. Climatologically, May 1996 was exceptional for producing weather conditions that both killed birds en masse and allowed the mortality to be documented. As a result, this is one of the more thoroughly documented instances of a weather-related mass mortality event during migration.

  17. Investigation of Different Forest Type’s Structure with Applying Nearest Neighbor Indices (Case Study: Gorazon District, Kheyrud Forest

    Directory of Open Access Journals (Sweden)

    V. Alijani

    2013-07-01

    Full Text Available To implement correct management of forest ecosystems, enough information in relation to the structures of tree species is necessary. In this study, the structures of trees species in Fagus, Fagus-Carpinus, Carpinus-Fagus and Carpinus-Quercus types were investigated and compared in Hyrcanian forest. The data used in this study was collected from 239 plots with an area of 1000 m2 in Gorazbon district of Kheyrud forest, and Crancod (ver. 1.3 software was employed to calculate the uniform angle (Wi, Mingling (DMi, DBH dominance (TDi and Height dominance (THi indices. The result of uniform angle index showed a random positioning for the trees in the studied types. Also, the result of mingling index showed a low mixture for four studied types. The result of this index indicated an intra-specific competition for Fagus orientalis and Carpinus betulus and an inter-specific competition for other species. The average value of DBH and Height dominance indices showed a relative similarity among the studied types. The result of these indices showed that some species such as Acer velutinum,، Tilia begonifolia and Alnus subcordata are dominant and species including Ulmus glabra and Diospyros lotus are dominated. The comparing of similar species structure showed a non significant difference for positioning, DBH and height dominance features in different types. Also, this comparison showed a significant difference in mingling feature of Carpinus betulus, Fagus orientalis, Acer velutinum, Tilia begonifolia, and also deadwoods in the studied types. The utilized indices in this study had a high ability in the description of forest types' structures and also the ecological features of trees species.

  18. Lake Tahoe Ca-Nv USA to Climate Change

    Science.gov (United States)

    Sahoo, G. B.; Schladow, S. G.; Reuter, J. E.; Coats, R. N.

    2011-12-01

    Observational studies indicate that climate at Lake Tahoe (CA-NV) basin is changing at faster rate. The impact of climate change on the lake was investigated using a suite of models and bias-corrected downscaled climate dataset generated from global circulation models. Our results indicate an increase of air temperature, a shift of snow to rainfall, a decrease of wind speed, and an onset of earlier snowmelt during the 21st Century. Combined, these changes could affect lake dynamics, ecosystems, water supply, and the winter recreational sport industry. The lake may fail to mix completely by the middle of this Century due to lake warming. Under this condition bottom dissolved oxygen would not be replenished leading to the significant release of bio-stimulatory ammonium-nitrogen and soluble phosphorus from the sediment. Both these nutrients are known to cause increased algal growth in the lake and would likely result in major changes to the lake's water quality and food web. Lake warming also increases water loss through evaporation, resulting in less available water for downstream domestic supply, agriculture, and recreation. Population growth and increased human demand for water will compound severity of problems in water quantity and quality. Thus, watershed planning and management should assess vulnerability to climatic variations through the application of basin-wide hydro-climatology, watershed soils, and lake response models to (1) improve drought, flood, and forest-fire forecasting, (2) assess hydrological trends, (3) estimate the potential effects of climate change on surface runoff and pollutant loads, and (4) evaluate response from various adaptation strategies.

  19. Variation in tree mortality and regeneration affect forest carbon recovery following fuel treatments and wildfire in the Lake Tahoe Basin, California, USA

    OpenAIRE

    Carlson, Chris H; Dobrowski, Solomon Z; Safford, Hugh D

    2012-01-01

    Abstract Background Forest fuel treatments have been proposed as tools to stabilize carbon stocks in fire-prone forests in the Western U.S.A. Although fuel treatments such as thinning and burning are known to immediately reduce forest carbon stocks, there are suggestions that these losses may be paid back over the long-term if treatments sufficiently reduce future wildfire severity, or prevent deforestation. Although fire severity and post-fire tree regeneration have been indicated as importa...

  20. A Model Study on the Role of Wetland Zones in Lake Eutrophication and Restoration

    Directory of Open Access Journals (Sweden)

    J.H. Janse

    2001-01-01

    Full Text Available Shallow lakes respond in different ways to changes in nutrient loading (nitrogen, phosphorus. These lakes may be in two different states: turbid, dominated by phytoplankton, and clear, dominated by submerged macrophytes. Both states are self-stabilizing; a shift from turbid to clear occurs at much lower nutrient loading than a shift in the opposite direction. These critical loading levels vary among lakes and are dependent on morphological, biological, and lake management factors. This paper focuses on the role of wetland zones. Several processes are important: transport and settling of suspended solids, denitrification, nutrient uptake by marsh vegetation (increasing nutrient retention, and improvement of habitat conditions for predatory fish. A conceptual model of a lake with surrounding reed marsh was made, including these relations. The lake-part of this model consists of an existing lake model named PCLake[1]. The relative area of lake and marsh can be varied. Model calculations revealed that nutrient concentrations are lowered by the presence of a marsh area, and that the critical loading level for a shift to clear water is increased. This happens only if the mixing rate of the lake and marsh water is adequate. In general, the relative marsh area should be quite large in order to have a substantial effect. Export of nutrients can be enhanced by harvesting of reed vegetation. Optimal predatory fish stock contributes to water quality improvement, but only if combined with favourable loading and physical conditions. Within limits, the presence of a wetland zone around lakes may thus increase the ability of lakes to cope with nutrients and enhance restoration. Validation of the conclusions in real lakes is recommended, a task hampered by the fact that, in the Netherlands, many wetland zones have disappeared in the past.

  1. Regional Geology of the Southern Lake Erie (Ohio) Bottom: A Seismic Reflection and Vibracore Study.

    Science.gov (United States)

    1982-12-01

    vibratory coring apparatus used to collect sediment cores is shown being lifted off the platform for deployment on the lake floor. A 36-meter-long scow from...the U.S. Army Engineer District, Buffalo, was used as the platform for phase II coring. The scow was transported by the Corps tugboat Washington (Fig...on the geologic history of the lake, and of use. II. PHYSICAL SETTING 1. Introduction. The Lake Erie basin is underlain by middle Paleozoic sedimentary

  2. Examining the utility of satellite-based wind sheltering estimates for lake hydrodynamic modeling

    Science.gov (United States)

    Van Den Hoek, Jamon; Read, Jordan S.; Winslow, Luke A.; Montesano, Paul; Markfort, Corey D.

    2015-01-01

    Satellite-based measurements of vegetation canopy structure have been in common use for the last decade but have never been used to estimate canopy's impact on wind sheltering of individual lakes. Wind sheltering is caused by slower winds in the wake of topography and shoreline obstacles (e.g. forest canopy) and influences heat loss and the flux of wind-driven mixing energy into lakes, which control lake temperatures and indirectly structure lake ecosystem processes, including carbon cycling and thermal habitat partitioning. Lakeshore wind sheltering has often been parameterized by lake surface area but such empirical relationships are only based on forested lakeshores and overlook the contributions of local land cover and terrain to wind sheltering. This study is the first to examine the utility of satellite imagery-derived broad-scale estimates of wind sheltering across a diversity of land covers. Using 30 m spatial resolution ASTER GDEM2 elevation data, the mean sheltering height, hs, being the combination of local topographic rise and canopy height above the lake surface, is calculated within 100 m-wide buffers surrounding 76,000 lakes in the U.S. state of Wisconsin. Uncertainty of GDEM2-derived hs was compared to SRTM-, high-resolution G-LiHT lidar-, and ICESat-derived estimates of hs, respective influences of land cover type and buffer width on hsare examined; and the effect of including satellite-based hs on the accuracy of a statewide lake hydrodynamic model was discussed. Though GDEM2 hs uncertainty was comparable to or better than other satellite-based measures of hs, its higher spatial resolution and broader spatial coverage allowed more lakes to be included in modeling efforts. GDEM2 was shown to offer superior utility for estimating hs compared to other satellite-derived data, but was limited by its consistent underestimation of hs, inability to detect within-buffer hs variability, and differing accuracy across land cover types. Nonetheless

  3. The remarkable story of the partial cutting study at the Dukes Experimental Forest

    Science.gov (United States)

    Laura S. Kenefic; Christel C. Kern

    2013-01-01

    This paper describes our recent and successful efforts to reopen the pioneering U.S. Forest Service "Partial Cutting Study" on the Dukes Experimental Forest in Michigan. This experiment in northern hardwood silviculture was initiated in 1926 and closed in 1966. Although the research conducted there informed the use of uneven-aged silviculture throughout the...

  4. A numerical study on hydrological impacts of forest restoration in the southern United States

    Science.gov (United States)

    Y.-Q. Liu

    2010-01-01

    Landscape in the southern United States changed dramatically during the 1930s and the following decades when massive agricultural and abandoned logging lands were converted to forest lands through natural restoration and silviculture. The impacts of this forest restoration on hydrology were investigated in this study by conducting numerical experiments with a regional...

  5. Effects of forest management on soil carbon: results of some long-term resampling studies

    Science.gov (United States)

    D.W. Johnson; Jennifer D. Knoepp; Wayne T. Swank; J. Shan; L.A. Morris; David H. D.H. van Lear; P.R. Kapeluck

    2002-01-01

    The effects of harvest intensity (sawlog, SAW; whole tree, WTH; and complete tree, CTH) on biomass and soil carbon (C) were studied in four forested sites in the Southeastern United States: (mixed deciduous forests at Oak Ridge, TN and Coweeta, NC; Pinus taeda at Clemson, SC; and P. eliottii at Bradford, FL). In general, harvesting had no lasting...

  6. Palaeolimnological assessment of environmental change over the last two centuries in oligotrophic Lake Nohipalu Valgjärv, southern Estonia

    Directory of Open Access Journals (Sweden)

    Heinsalu, Atko

    2009-06-01

    Full Text Available The main objectives of this study were to reconstruct the environmental conditions for a small oligotrophic lake during the last two centuries, to determine if the environment of the lake was anthropogenically mediated, and to assess the pre-impact reference conditions with palaeolimnological techniques. A short sediment core from Lake Nohipalu Valgjärv was analysed in detail for diatom assemblages as well as for loss-on-ignition measurements. Accurate chronology of the sediment core was established and evaluated by different independent approaches – 210Pb, 137Cs, and 241Am dating, and the distribution of spheroidal fly-ash particles in sediments. Quantitative inference models based on sedimentary diatoms were applied to reconstruct changes in past lake water pH. Before the mid-19th century, Nohipalu Valgjärv was an oligotrophic lake with clear water continuously transparent down to the bottom and with rich benthic diatom flora. Since the early second half of the 19th century, presumably as a result of forest logging around the lake, water transparency decreased and benthic diatom productivity diminished, and the lake did not recover any more to natural baseline conditions. Due to peat mining activities in the Meenikunno bog, the quality of lake water has changed during the last two decades. The lowered lake level, deteriorated light climate, and decreased pH are the most important environmental variables that have influenced the lake ecosystem.

  7. A multi-proxy-study of the 8.2-event in varved lake sediments and the potential of NPPs

    DEFF Research Database (Denmark)

    Enevold, Renée; Odgaard, Bent Vad

    2014-01-01

    Before, during and after the 8.2-event Lake Sarup (55º12’19’’N, 10º04’04’’E) deposited annually laminated sediments (Bjerring et al. 2013). Stable isotopes, wiggle-matching of radiocarbon dates and sedimentology of multicore studies reveal pronounced water level changes as a response to climate...... knowledge of their response to the inferred environmental changes in Lake Sarup may add to their interpretational value when recorded in other contexts. The multi-proxy approach allows us to study the potential correlation of unknown NPP’s with the sediment accumulation rates, pollen assemblages, total...

  8. Final report of the AECL/SKB Cigar Lake analog study. AECL research No. AECL-10851

    Energy Technology Data Exchange (ETDEWEB)

    Cramer, J.J.; Smellie, J.A.T. (eds.)

    1994-07-15

    AECL has conducted natural analog studies on the Cigar Lake uranium deposit in northern Saskatchewan since 1984 as part of the Canadian Nuclear Fuel Waste Management Program. This report provides background information and summarizes the results of the study, emphasizing the analog aspects and the implications of modelling activities related to the performance assessment of disposal concepts for nuclear fuel wastes developed in both Canada and Sweden. The study was undertaken to obtain an understanding of the process involved in, and the effects of, steady-state water-rock interaction and trace-element migration in and around the deposit, including paleo-migration processes since the deposit was formed. To achieve these objectives, databases and models were produced to evaluate the equilibrium thermodynamic codes and databases; the role of colloids, organics, and microbes in transport processes for radionuclides; and the stability of UO2 and the influence of radiolysis on UO2 dissolution and radionuclide migration.

  9. USE OF POM AND ARTIFICIAL NEURAL NETWORKS IN THE THREEDIMENSIONAL MODELING OF LAKES : GOKPINAR DAM RESERVOIR AS A CASE STUDY

    Directory of Open Access Journals (Sweden)

    Mahmut FIRAT

    2006-01-01

    Full Text Available The circulation pattern in lakes and reservoirs varies according to many external factors. In situ measurement of the occuring flow pattern in every point of the lake is a very costly and hard task. For this reason, models determining the velocities and surface fluctuations are developed by using computers. The use of these models enables the generation of the foundation for the prediction of possible environmental problems and water pollution concentrations. Today, three dimensional models are widely used in the modelling of lakes and reservoirs. In this study, the velocity profiles and surface fluctuation values generated under various wind speed and directions at some sections in Gokpinar Lake in Denizli are obtained by applying artificial neural networks (ANN on the results of three dimensional hydrodynamic model of the lake made with Princeton Ocean Model (POM. The developed ANN model is applied to the same sections for different wind conditions and it is found that the results are in accordance with the results of POM. As a result of the comparisons of the models, the superiorities of the models on each other at the model generation and solution phases are determined and mentioned.

  10. Glacial lake inventory and lake outburst potential in Uzbekistan.

    Science.gov (United States)

    Petrov, Maxim A; Sabitov, Timur Y; Tomashevskaya, Irina G; Glazirin, Gleb E; Chernomorets, Sergey S; Savernyuk, Elena A; Tutubalina, Olga V; Petrakov, Dmitriy A; Sokolov, Leonid S; Dokukin, Mikhail D; Mountrakis, Giorgos; Ruiz-Villanueva, Virginia; Stoffel, Markus

    2017-08-15

    Climate change has been shown to increase the number of mountain lakes across various mountain ranges in the World. In Central Asia, and in particular on the territory of Uzbekistan, a detailed assessment of glacier lakes and their evolution over time is, however lacking. For this reason we created the first detailed inventory of mountain lakes of Uzbekistan based on recent (2002-2014) satellite observations using WorldView-2, SPOT5, and IKONOS imagery with a spatial resolution from 2 to 10m. This record was complemented with data from field studies of the last 50years. The previous data were mostly in the form of inventories of lakes, available in Soviet archives, and primarily included localized in-situ data. The inventory of mountain lakes presented here, by contrast, includes an overview of all lakes of the territory of Uzbekistan. Lakes were considered if they were located at altitudes above 1500m and if lakes had an area exceeding 100m 2 . As in other mountain regions of the World, the ongoing increase of air temperatures has led to an increase in lake number and area. Moreover, the frequency and overall number of lake outburst events have been on the rise as well. Therefore, we also present the first outburst assessment with an updated version of well-known approaches considering local climate features and event histories. As a result, out of the 242 lakes identified on the territory of Uzbekistan, 15% are considered prone to outburst, 10% of these lakes have been assigned low outburst potential and the remainder of the lakes have an average level of outburst potential. We conclude that the distribution of lakes by elevation shows a significant influence on lake area and hazard potential. No significant differences, by contrast, exist between the distribution of lake area, outburst potential, and lake location with respect to glaciers by regions. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Influence of different forest system management practices on leaf litter decomposition rates, nutrient dynamics and the activity of ligninolytic enzymes: a case study from central European forests.

    Science.gov (United States)

    Purahong, Witoon; Kapturska, Danuta; Pecyna, Marek J; Schulz, Elke; Schloter, Michael; Buscot, François; Hofrichter, Martin; Krüger, Dirk

    2014-01-01

    Leaf litter decomposition is the key ecological process that determines the sustainability of managed forest ecosystems, however very few studies hitherto have investigated this process with respect to silvicultural management practices. The aims of the present study were to investigate the effects of forest management practices on leaf litter decomposition rates, nutrient dynamics (C, N, Mg, K, Ca, P) and the activity of ligninolytic enzymes. We approached these questions using a 473 day long litterbag experiment. We found that age-class beech and spruce forests (high forest management intensity) had significantly higher decomposition rates and nutrient release (most nutrients) than unmanaged deciduous forest reserves (Pforest management (low forest management intensity) exhibited no significant differences in litter decomposition rate, C release, lignin decomposition, and C/N, lignin/N and ligninolytic enzyme patterns compared to the unmanaged deciduous forest reserves, but most nutrient dynamics examined in this study were significantly faster under such near-to-nature forest management practices. Analyzing the activities of ligninolytic enzymes provided evidence that different forest system management practices affect litter decomposition by changing microbial enzyme activities, at least over the investigated time frame of 473 days (laccase, Pforest system management practices can significantly affect important ecological processes and services such as decomposition and nutrient cycling.

  12. 36 CFR 7.2 - Crater Lake National Park.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Crater Lake National Park. 7.2 Section 7.2 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.2 Crater Lake National Park. (a) Fishing...

  13. Lake Michigan lake trout PCB model forecast post audit

    Science.gov (United States)

    Scenario forecasts for total PCBs in Lake Michigan (LM) lake trout were conducted using the linked LM2-Toxics and LM Food Chain models, supported by a suite of additional LM models. Efforts were conducted under the Lake Michigan Mass Balance Study and the post audit represents th...

  14. Inclusive business model in tapioca starch industry in Lake Toba area: a case study

    Science.gov (United States)

    Tampubolon, S.; Manik, Y.

    2018-04-01

    The notion of inclusive business calls for additional focus and innovation in the way companies do business which seeks to contribute to poverty alleviation by including Bottom of the Pyramids (BoP) communities within its value chain while not losing sight of the ultimate goal of business. Lake Toba Area has potentials in providing chances for doing businesses. On the other hand, the growth of market size is rather slow and demographically still dominated by BoP. This is a case study which seeks to investigate to what extent the Inclusive Business Model (IBM) is adopted in the strategic planning and applied in the operational management of companies that operate in Lake Toba Area. The study was conducted in qualitative basis. The observation was conducted by gathering data and information through a series of interviews with the top management and desk study of the business plan in a tapioca starch industry in Toba Samosir Regency. The collected data and information were then analyzed qualitatively by comparing them with criteria and parameters of IBM suggested in a vast body of literature. The reference by which the IBM is referred in this study is a series of criteria which is synthesized from a literature review on a vast body of literature about IBM. From data analysis, it is evident that IBM has been incorporated in the strategic plan and applied in the operational activities of the object of this study. However, we also found some rooms for improvement such as expanding the involvement of BoP in their value chain as consumers, by which some innovation in the product diversification is required.

  15. Hiawatha National Forest Riparian Inventory: A Case Study

    Science.gov (United States)

    Abood, S. A.

    2014-12-01

    Riparian areas are dynamic, transitional ecotones between aquatic and terrestrial ecosystems with well-defined vegetation and soil characteristics. Riparian areas offers wildlife habitat and stream water quality, offers bank stability and protects against erosions, provides aesthetics and recreational value, and other numerous valuable ecosystem functions. Quantifying and delineating riparian areas is an essential step in riparian monitoring, riparian management/planning and policy decisions, and in preserving its valuable ecological functions. Previous approaches to riparian areas mapping have primarily utilized fixed width buffers. However, these methodologies only take the watercourse into consideration and ignore critical geomorphology, associated vegetation and soil characteristics. Other approaches utilize remote sensing technologies such as aerial photos interpretation or satellite imagery riparian vegetation classification. Such techniques requires expert knowledge, high spatial resolution data, and expensive when mapping riparian areas on a landscape scale. The goal of this study is to develop a cost effective robust workflow to consistently map the geographic extent and composition of riparian areas within the Hiawatha National Forest boundary utilizing the Riparian Buffer Delineation Model (RBDM) v3.0 and open source geospatial data. This approach recognizes the dynamic and transitional natures of riparian areas by accounting for hydrologic, geomorphic and vegetation data as inputs into the delineation process and the results would suggests incorporating functional variable width riparian mapping within watershed management planning to improve protection and restoration of valuable riparian functionality and biodiversity.

  16. Response of lake chemistry to atmospheric deposition and climate in selected Class I wilderness areas in the western United States, 1993-2009

    Science.gov (United States)

    Mast, M. Alisa

    2011-01-01

    The U.S. Geological Survey, in cooperation with the U.S. Department of Agriculture Forest Service, Air Resource Management, conducted a study to evaluate long-term trends in lake-water chemistry for 64 high-elevation lakes in selected Class I wilderness areas in Colorado, Idaho, Utah, and Wyoming during 1993 to 2009. Understanding how and why lake chemistry is changing in mountain areas is essential for effectively managing and protecting high-elevation aquatic ecosystems. Trends in emissions, atmospheric deposition, and climate variables (air temperature and precipitation amount) were evaluated over a similar period of record. A main objective of the study was to determine if changes in atmospheric deposition of contaminants in the Rocky Mountain region have resulted in measurable changes in the chemistry of high-elevation lakes. A second objective was to investigate linkages between lake chemistry and air temperature and precipitation to improve understanding of the sensitivity of mountain lakes to climate variability.

  17. 36 CFR 7.57 - Lake Meredith National Recreation Area.

    Science.gov (United States)

    2010-07-01

    ... of the Sanford Dam intake tower, and on the waters of the Canadian River. (2) PWC may operate on Lake... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Lake Meredith National... THE INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.57 Lake Meredith National...

  18. 36 CFR 7.69 - Ross Lake National Recreation Area.

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Ross Lake National Recreation... INTERIOR SPECIAL REGULATIONS, AREAS OF THE NATIONAL PARK SYSTEM § 7.69 Ross Lake National Recreation Area... snowmobiles the following locations within the Ross Lake National Recreation Area: (1) State Highway 20, that...

  19. Forest report 2003. Forest ecosystem study for Hessen. Forest, water, weather; Waldzustandsbericht 2003. Waldoekosystemstudie Hessen. Wald und Wasser - Witterung

    Energy Technology Data Exchange (ETDEWEB)

    Paar, U.; Gawehn, P.; Rockel, A.; Scheler, B.; Schoenfelder, E.; Eichhorn, J. (comps.) [Hessen-Forst, Hannoversch Muenden (Germany)

    2003-07-01

    Between 1984 an 1992 defoliation increased in Hesse. From the year 2000 on, vitality of trees remained unchanged. Since 2001, crown situation starts getting better. Mainly young Fagus sylvatica shows quite good vitality in 2003. However, the overall level of tree vitality still can not be compared to the year 1984. The Rhein-Main area has to be considered as overstrained. Acid deposition has clearly improved, e.g. sulphur. However, nitrogen compounds namely NH4 shows no indication of a clear reduction in forest ecosystems of Hesse. Ozon levels are increasing steadily. The summer of 2003 was extremely warm and dry. Responses of vegetation and soils may occur in 2004. (orig.) [German] Nach einem raschen Anstieg der mittleren Kronenverlichtung zwischen 1984 (11%) und 1992 (25%) war etwa bis 2000 eine Stagnation der Entwicklung zu verzeichnen. In den letzten Jahren mehren sich in Hessen Anzeichen einer Verbesserung des Waldzustandes. Guenstig ist die Entwicklung der juengeren Baeume. Hier ist vor allem die Buche zu nennen. Der Anteil der seit dem letzten Jahr abgestorbenen Baeume ist sehr gering. Noch ist aber die Vitalitaet des hessischen Waldes von 1984 insgesamt nicht wieder erreicht (2003: 21% gegenueber 11%, 1984). Die Region Rhein-Main ist hinsichtlich des Zustandes des Waldes nach wie vor besonders belastet. Trotz heute wesentlich geringerer Saeure- und Schwefeleintraege in den hessischen Wald wirken die jahrzehntelangen hohen Immissionen erheblich nach. Dies glit vor allem fuer die Beschaffenheit des Bodensickerwassers, einer wesentlichen Ernaehrungsgrundlage der Waldbaeume. Nahezu unveraendert hoch ist der Stickstoffeintrag (Kronentraufe) in hessische Waelder. Auch die Ozongehalte der bodennahen Luft lassen keine Tendenz zur Verringerung erkennen. Spitzenwerte der Jahre 1994/1995 wurden jedoch nicht erreicht. Weitere Anstrengungen zur Immissionsminderung sind erforderlich. Fuer den Sommer 2003 wurde die hoechste Durchschnittstemperatur seit 1984 gemessen

  20. Study on environmental background values of uranium in water of Dongting Lake system

    International Nuclear Information System (INIS)

    Zhai Pengji; Kang Tiesheng

    1987-01-01

    Study on environmental background values in water is the base of evaluating water quality and also is the foundational work of studying the law of distribution, accumulation and transfer of the elements. Research on background values of U in water not only can understand radioactive level but also has actual significance for the general survey of U by water. In the work uranium contents were determined by fission track analytical technique in the filtered and unfiltered specimens of river water, reservoir water and spring water taken from more than one hundred sections located in Dongting Lake system and the statistical process of data were carried out by computer. The environmental background values in water of various river system were obtained and compared with the situation of home and abroad. The seasonal variety of uranium content and the level of U in reservoir, spring water and natural reserve were discussed

  1. The Impact of Charcoal Production on Forest Degradation: a Case Study in Tete, Mozambique

    Science.gov (United States)

    Sedano, F.; Silva. J. A.; Machoco, R.; Meque, C. H.; Sitoe, A.; Ribeiro, N.; Anderson, K.; Ombe, Z. A.; Baule, S. H.; Tucker, C. J.

    2016-01-01

    Charcoal production for urban energy consumption is a main driver of forest degradation in sub-Saharan Africa. Urban growth projections for the continent suggest that the relevance of this process will increase in the coming decades. Forest degradation associated to charcoal production is difficult to monitor and commonly overlooked and underrepresented in forest cover change and carbon emission estimates. We use a multi-temporal dataset of very high-resolution remote sensing images to map kiln locations in a representative study area of tropical woodlands in central Mozambique. The resulting maps provided a characterization of the spatial extent and temporal dynamics of charcoal production. Using an indirect approach we combine kiln maps and field information on charcoal making to describe the magnitude and intensity of forest degradation linked to charcoal production, including aboveground biomass and carbon emissions. Our findings reveal that forest degradation associated to charcoal production in the study area is largely independent from deforestation driven by agricultural expansion and that its impact on forest cover change is in the same order of magnitude as deforestation. Our work illustrates the feasibility of using estimates of urban charcoal consumption to establish a link between urban energy demands and forest degradation. This kind of approach has potential to reduce uncertainties in forest cover change and carbon emission assessments in sub-Saharan Africa.

  2. Multifunctionality assessment in forest planning at landscape level. The study case of Matese Mountain Community (Italy.

    Directory of Open Access Journals (Sweden)

    Umberto Di Salvatore

    2013-12-01

    Full Text Available Normal 0 14 false false false MicrosoftInternetExplorer4 The main objective is to improve a method that aims at evaluating forest multifunctionality from a technical and practical point of view. A methodological approach - based on the index of forest multifunctionality level - is proposed to assess the “fulfilment capability” of a function providing an estimate of performance level of each function in a given forest. This method is aimed at supporting technicians requested to define most suitable management guidelines and silvicultural practices in the framework of a Forest Landscape Management Plan (FLMP. The study area is the Matese district in southern Apennines (Italy, where a landscape planning experimentation was implemented. The approach includes the qualitative and quantitative characterization of selected populations, stratified by forest category by a sampling set of forest inventory plots. A 0.5 ha area around the sample plot was described by filling a form including the following information: site condition, tree species composition, stand origin and structure, silvicultural system, health condition, microhabitats presence. In each sample plot, both the multifunctionality assessment and the estimate of the effect of alternative management options on ecosystem goods and services, were carried out. The introduction of the term “fulfilment capability” and the modification of the concept of priority level - by which the ranking of functions within a plot is evaluated - is an improvement of current analysis method. This enhanced approach allows to detect the current status of forest plot and its potential framed within the whole forest. Assessing functional features of forests with this approach reduces the inherent subjectivity and allows to get useful information on forest multifunctionality to support forest planners in defining management guidelines consistent with current status and potential evolutive pattern.

  3. Contaminants of emerging concern presence and adverse effects in fish: A case study in the Laurentian Great Lakes

    Science.gov (United States)

    Jorgenson, Zachary G.; Thomas, Linnea M.; Elliott, Sarah M.; Cavallin, Jenna E.; Randolph, Eric C.; Choy, Steven J.; Alvarez, David; Banda, Jo A.; Gefell, Daniel J.; Lee, Kathy E.; Furlong, Edward T.; Schoenfuss, Heiko L.

    2018-01-01

    The Laurentian Great Lakes are a valuable natural resource that is affected by contaminants of emerging concern (CECs), including sex steroid hormones, personal care products, pharmaceuticals, industrial chemicals, and new generation pesticides. However, little is known about the fate and biological effects of CECs in tributaries to the Great Lakes. In the current study, 16 sites on three rivers in the Great Lakes basin (Fox, Cuyahoga, and Raquette Rivers) were assessed for CEC presence using polar organic chemical integrative samplers (POCIS) and grab water samplers. Biological activity was assessed through a combination of in vitro bioassays (focused on estrogenic activity) and in vivo assays with larval fathead minnows. In addition, resident sunfish, largemouth bass, and white suckers were assessed for changes in

  4. Contaminants of emerging concern presence and adverse effects infish: A case study in the Laurentian Great Lakes

    Science.gov (United States)

    Jorgenson, Zachary G.; Thomas, Linnea M.; Elliott, Sarah M.; Cavallin, Jenna E.; Randolph, Eric C.; Choy, Steven J.; Alvarez, David; Banda, Jo A.; Gefell, Daniel J.; Lee, Kathy E.; Furlong, Edward T.; Schoenfuss, Heiko L.

    2018-01-01

    The Laurentian Great Lakes are a valuable natural resource that is affected by contaminants of emerging concern (CECs), including sex steroid hormones, personal care products, pharmaceuticals, industrial chemicals, and new generation pesticides. However, little is known about the fate and biological effects of CECs in tributaries to the Great Lakes. In the current study, 16 sites on three rivers in the Great Lakes basin (Fox, Cuyahoga, and Raquette Rivers) were assessed for CEC presence using polar organic chemical integrative samplers (POCIS) and grab water samplers. Biological activity was assessed through a combination of in vitro bioassays (focused on estrogenic activity) and in vivo assays with larval fathead minnows. In addition, resident sunfish, largemouth bass, and white suckers were assessed for changes in

  5. An unsupervised two-stage clustering approach for forest structure classification based on X-band InSAR data - A case study in complex temperate forest stands

    Science.gov (United States)

    Abdullahi, Sahra; Schardt, Mathias; Pretzsch, Hans

    2017-05-01

    Forest structure at stand level plays a key role for sustainable forest management, since the biodiversity, productivity, growth and stability of the forest can be positively influenced by managing its structural diversity. In contrast to field-based measurements, remote sensing techniques offer a cost-efficient opportunity to collect area-wide information about forest stand structure with high spatial and temporal resolution. Especially Interferometric Synthetic Aperture Radar (InSAR), which facilitates worldwide acquisition of 3d information independent from weather conditions and illumination, is convenient to capture forest stand structure. This study purposes an unsupervised two-stage clustering approach for forest structure classification based on height information derived from interferometric X-band SAR data which was performed in complex temperate forest stands of Traunstein forest (South Germany). In particular, a four dimensional input data set composed of first-order height statistics was non-linearly projected on a two-dimensional Self-Organizing Map, spatially ordered according to similarity (based on the Euclidean distance) in the first stage and classified using the k-means algorithm in the second stage. The study demonstrated that X-band InSAR data exhibits considerable capabilities for forest structure classification. Moreover, the unsupervised classification approach achieved meaningful and reasonable results by means of comparison to aerial imagery and LiDAR data.

  6. Historical framework to explain long-term coupled human and natural system feedbacks: application to a multiple-ownership forest landscape in the northern Great Lakes region, USA

    Science.gov (United States)

    Michelle M. Steen-Adams; Nancy Langston; Mark D. O. Adams; David J. Mladenoff

    2015-01-01

    Current and future human and forest landscape conditions are influenced by the cumulative, unfolding history of socialecological interactions. Examining past system responses, especially unintended consequences, can reveal valuable insights that promote learning and adaptation in forest policy and management. Temporal couplings are complex, however; they can be...

  7. Early Growth of Eastern White Pine Seed Sources in the Lake States

    Science.gov (United States)

    James P. King; Hans Nienstaedt

    1968-01-01

    In 5-year-old test plantations in Minnesota, Wisconsin, and Michigan, eastern white pine seedlings from seed sources that are fast-growing in one location are not necessarily fast-growing in other locations. Until more intensive studies of the Lake States seed sources can be made, foresters should confine collection of white pine seed to local stands.

  8. Holocene pollen record from Lake Sokoch, interior Kamchatka (Russia), and its paleobotanical and paleoclimatic interpretation

    Science.gov (United States)

    Dirksen, Veronika; Dirksen, Oleg; van den Bogaard, Christel; Diekmann, Bernhard

    2015-11-01

    A pollen record, obtained from sediments of Lake Sokoch in mountain interior of the Kamchatka Peninsula, covers the last ca. 9600 years (all ages are given in calibrated years BP). Variations in local components, including pollen, spores and non-pollen palynomorphs, and related changes in sedimentation document the lake development from initially seepage and shallow basin to deeper lake during the mid Holocene and then to the hydrologically open system during the late Holocene. The studies of volcanic ashes from the lake sediment core show their complex depositional histories. Lake Sokoch occupies a former proglacial basin between two terminal moraines of the LGM time. The undated basal part of record before ca. 9600 year BP, however, does not reflect properly cold conditions. At that time, although shrublands and tundra dominated, stone birch and white birch forests have already settled in surroundings; the presence of alder woodland indicates wet and maritime-like climate. The subsequent forest advance suggesting warmer conditions was interrupted by the ca. 8000-7600 year BP spell of cooler climate. The following culmination of warmth is bracketed by the evidence of the first maximal forest extent between ca. 7400 and 5100 year BP. During that time, dramatic retreat of alder forest suggests a turn from maritime-like to more continental climate conditions. The cool and wet pulse after ca. 5100 year BP was pronounced as forests retreat while shrublands, meadows and bogs extended. An expansion of white birch forest since ca. 3500 year BP reflected the onset of drier climate, strengthening continentality and seasonal contrast. The second maximum of forests dominated by both stone and white birches occurred between ca. 2200 and 1700 year BP and indicated warming in association with relatively dry and increasingly continental climate. The following period was wetter and cooler, and minor outbreak of alder forest around ca. 1500 year BP suggests a short-term return of

  9. Lake ecosystem response to climate change 8200 years ago. A multi-proxy study at Lake Højby Sø, Denmark

    DEFF Research Database (Denmark)

    Rasmussen, Peter; Hede, Mikkel Ulfeldt; Noe-Nygaard, Nanna

    2009-01-01

    of the North Atlantic is projected by almost all global-warming models (e.g. IPCC 2007). In Denmark the 8.2 kyr event pre-dates the introduction of agriculture (by more than two millennia) and any other major human impact on the environment, so allowing the anthropogenic factor to be disregarded. At Lake Højby...... of climate and the effects of human activities. These problems also complicate the prediction of possible future climate influence on lake ecology. A way of circumventing these problems is the use of lake sediment records which contain a wealth of information about past lake history over long time scales...

  10. Use of MODIS Terra Imagery to Estimate Surface Water Quality Standards, Using Lake Thonotosassa, Florida, as a Case Study

    Science.gov (United States)

    Moreno, Max J.; Al-Hamdan, Mohammad Z.; Estes, Maurice G., Jr.; Rickman, Douglas L.

    2010-01-01

    Lake Thonotosassa is a highly eutrophied lake located in an area with rapidly growing population in the Tampa Bay watershed, Florida. The Florida Administrative Code has designated its use for "recreation, propagation and maintenance of a healthy, well-balanced population of fish and wildlife." Although this lake has been the subject of efforts to improve water quality since 1970, overall water quality has remained below the acceptable state standards, and has a high concentration of nutrients. This condition is of great concern to public health since it has favored episodic blooms of Cyanobacteria. Some Cyanobacterial species release toxins that can reach humans through drinking water, fish consumption, and direct contact with contaminated water. The lake has been historically popular for fishing and water sports, and its overflow water drains into the Hillsborough River, the main supply of municipal water for the City of Tampa, this explains why it has being constantly monitored in situ for water quality by the Environmental Protection Commission of Hillsborough County (EPC). Advances in remote sensing technology, however, open the possibility of facilitating similar types of monitoring in this and similar lakes, further contributing to the implementation of surveillance systems that would benefit not just public health, but also tourism and ecosystems. Although traditional application of this technology to water quality has been focused on much larger coastal water bodies like bays and estuaries, this study evaluates the feasibility of its application on a 46.6 km2 freshwater lake. Using surface reflectance products from Moderate-Resolution Imaging Spectroradiometer (MODIS) Terra, this study evaluates associations between remotely sensed data and in situ data from the EPC. The parameters analyzed are the surface water quality standards used by the State of Florida and general indicators of trophic status.

  11. Water quality and remote sensing: A case study of Lake Naivasha, Kenya

    CSIR Research Space (South Africa)

    Majozi, NP

    2012-10-01

    Full Text Available ) of Lake Naivasha, Kenya, using Medium Resolution Imaging Spectrometer (MERIS). Radiometric data was collected at Lake Naivasha. The Kd model was calibrated using in situ data and validated using MERIS 490 nm band, giving an RSME 0.43 and MAE 31%. Zeu...

  12. The evaluation of hydrochemical parameters and lithological characteristics of sediments in some lakes from Danube Delta - Romania Study case: Matita, Babina, Rosu, Uzlina and Isacova Lakes - 2010.

    Science.gov (United States)

    Catianis, I.; Grosu, D.; Radan, S.

    2012-04-01

    This study attempts to estimate the quality of water and sediments from five lakes of Danube Delta - Romania. Due to the great variety of plant and animal species, delta lakes are considered sensitive ecosystems which may become quite susceptible to anthropogenic influences. The water and sediment samples were gathered from a considerable number of sampling stations during the two campaigns performed in the summer and autumn of 2010. Different techniques were applied to assay variations in surface waters and lacustrine sediment quality. Water samples measured parameters were: dissolved oxygen, temperature, electrical conductivity, total dissolved solids, pH, redox potential, nitrates, nitrites, phosphates, sulphates etc. The main lithological parameters studied were: total organic matter, carbonates and siliciclastic material. The preliminary results indicate that these investigated lakes are quite influenced by external factors as: morphological features, climatic parameters (pressure, humidity, temperature, wind-speed, rainfall etc) and their position within the deltaic hydrological network. Performed analyses showed that the correlations between different parameters differ with respect to sampling station positions. The physico-chemical characteristics of the lakes and connection canals show small variation ranges. In some sampling stations, lower concentration of oxygen and medium pH change from slightly alkaline to alkaline were incidentally observed. The registered data also confirmed the influences of seasonal characteristics. Chemical analyses do not show high values for nitrates, nitrites and sulphates. As regards to phosphate concentration we found out some higher values. In this respect, we have to perform other detailed chemical analyses in order to establish their origin in water. Overall the physico-chemical investigations reveal normal values, which are in agreement with environmental quality standards for surface waters. Sediment cores present

  13. INVISTIGATION ON CANOPY HEIGHT AND DENSITY DIFFERENTIATIONS IN THE MANAGED AND UNMANAGED FOREST STANDS USING LIDAR DATA (CASE STUDY: SHASTKALATEH FOREST, GORGAN

    Directory of Open Access Journals (Sweden)

    Sh. Shataee

    2015-12-01

    Full Text Available Forest management plans are interesting to keep the forest stand natural composite and structure after silvicultural and management treatments. In order to investigate on stand differences made by management treatments, comparing of these stands with unmanaged stands as natural forests is necessary. Aerial laser scanners are providing suitable 3D information to map the horizontal and vertical characteristics of forest structures. In this study, different of canopy height and canopy cover variances between managed and unmanaged forest stands as well as in two dominant forest types were investigated using Lidar data in Dr. Bahramnia forest, Northern Iran. The in-situ information was gathered from 308 circular plots by a random systematic sampling designs. The low lidar cloud point data were used to generate accurate DEM and DSM models and plot-based height statistics metrics and canopy cover characteristics. The significant analyses were done by independent T-test between two stands in same dominant forest types. Results showed that there are no significant differences between canopy cover mean in two stands as well as forest types. Result of statistically analysis on height characteristics showed that there are a decreasing the forest height and its variance in the managed forest compared to unmanaged stands. In addition, there is a significant difference between maximum, range, and mean heights of two stands in 99 percent confidence level. However, there is no significant difference between standard deviation and canopy height variance of managed and unmanged stands. These results showd that accomplished management treatments and cuttings could lead to reducing of height variances and converting multi-layers stands to two or single layers. Results are also showed that the canopy cover densities in the managed forest stands are changing from high dense cover to dense cover.

  14. A floristic study of Salaheddinkola Forests, Nowshahr, Iran

    Directory of Open Access Journals (Sweden)

    Omid Esmailzadeh

    2014-11-01

    Full Text Available This paper reports the floristic survey on the Salaheddinkola forests (Nowshahr. These forests posses high variations in elevation ranges and special physiographic properties, which form the growth platform for most of the typical Hyrcanian forest species. The floristic-physiognomic investigation of the region was performed using field-walk procedure and revealed 237 plant species belonging to 196 genera and 85 families. The important families were Asteraceae, Poaceae, Rosaceae, Lamiaceae and Fabaceae with 23, 20, 14, 13 and 10 species, respectively which represented 33.17 percent of the total species. According to Raunkaiaer method, Cryptophytes (28.7%, Hemicryptophytes (27.5% and Phanerophytes (22.5% were the most important structure groups of the local biological spectrum followed by Therophytes (17.7% and Chamaephytes (3.4% Chorotypes. According to Zohary, most of the identified species belonged to Euro-Siberian and Pluriregional regions with 79 (33.6% and 62 (26% taxa, respectively.

  15. Population-Based Study on the Effect of a Forest Environment on Salivary Cortisol Concentration.

    Science.gov (United States)

    Kobayashi, Hiromitsu; Song, Chorong; Ikei, Harumi; Park, Bum-Jin; Lee, Juyoung; Kagawa, Takahide; Miyazaki, Yoshifumi

    2017-08-18

    The purpose of this study was to evaluate the effect of a forest environment on salivary cortisol concentration, particularly on the characteristics of its distribution. The participants were 348 young male subjects. The experimental sites were 34 forests and 34 urban areas across Japan. The subjects viewed the landscape (forest or urban environment) for a period of 15 min while sitting in a chair. Saliva was sampled from the participants at the end of this 15-min period and then analyzed for cortisol concentration. Differences in the skewness and kurtosis of the distributions between the two environments were tested by performing a permutation test. The cortisol concentrations exhibited larger skewness (0.76) and kurtosis (3.23) in a forest environment than in an urban environment (skewness = 0.49; kurtosis = 2.47), and these differences were statistically significant. The cortisol distribution exhibited a more peaked and longer right-tailed curve in a forest environment than in an urban environment.

  16. A Passive Microwave L-Band Boreal Forest Freeze/Thaw and Vegetation Phenology Study

    Science.gov (United States)

    Roy, A.; Sonnentag, O.; Pappas, C.; Mavrovic, A.; Royer, A.; Berg, A. A.; Rowlandson, T. L.; Lemay, J.; Helgason, W.; Barr, A.; Black, T. A.; Derksen, C.; Toose, P.

    2016-12-01

    The boreal forest is the second largest land biome in the world and thus plays a major role in the global and regional climate systems. The extent, timing and duration of seasonal freeze/thaw (F/T) state influences vegetation developmental stages (phenology) and, consequently, constitute an important control on how boreal forest ecosystems exchange carbon, water and energy with the atmosphere. The effective retrieval of seasonal F/T state from L-Band radiometry was demonstrated using satellite mission. However, disentangling the seasonally differing contributions from forest overstory and understory vegetation, and the soil surface to the satellite signal remains challenging. Here we present initial results from a radiometer field campaign to improve our understanding of the L-Band derived boreal forest F/T signal and vegetation phenology. Two L-Band surface-based radiometers (SBR) are installed on a micrometeorological tower at the Southern Old Black Spruce site in central Saskatchewan over the 2016-2017 F/T season. One radiometer unit is installed on the flux tower so it views forest including all overstory and understory vegetation and the moss-covered ground surface. A second radiometer unit is installed within the boreal forest overstory, viewing the understory and the ground surface. The objectives of our study are (i) to disentangle the L-Band F/T signal contribution of boreal forest overstory from the understory and ground surface, (ii) to link the L-Band F/T signal to related boreal forest structural and functional characteristics, and (iii) to investigate the use of the L-Band signal to characterize boreal forest carbon, water and energy fluxes. The SBR observations above and within the forest canopy are used to retrieve the transmissivity (γ) and the scattering albedo (ω), two parameters that describe the emission of the forest canopy though the F/T season. These two forest parameters are compared with boreal forest structural and functional

  17. Further study on source parameters at Quirke Mine, Elliot Lake, Ontario

    International Nuclear Information System (INIS)

    Chen, S.

    1991-01-01

    A further analysis on source parameters for thirty-seven mining-induced seismic events at Quirke Mine, Elliot Lake, Ontario, has been carried out to study the self-similarity assumption in scaling law of seismic spectrum for mining-induced microearthquakes, and to understand the focal mechanism in the mine. Evidence from high P-wave energy in a ratio E p /E s of 5% to 30%, and about 80% of the events with E s /E p L ). For the same total seismic energy, the apparent stress is limited by 80 GN.m and 800 GN.m of seismic moment. The observed stress drop is dependent on the seismic moment, which implies a breakdown in scaling law for events induced by mining. An analysis of peak particle velocity and acceleration presents the evidence for seismic attenuation over the fractured zone above the rock burst area in the mine

  18. Transmission studies of intestinal schistosomiasis in Lake Albert, Uganda and experimental compatibility of local Biomphalaria spp

    DEFF Research Database (Denmark)

    Kazibwe, F.; Makanga, B.; Rubaire-Akiiki, C.

    2010-01-01

    Despite ongoing preventive chemotherapy campaigns, intestinal schistosomiasis is hyper-endemic in shoreline communities living along Lake Albert, Uganda. To provide a deeper insight into the local epidemiology of Schistosoma mansoni, a variety of field-based studies were undertaken focusing upon...... schistosome-snail interactions and confirmation of transmission foci. Cercarial shedding patterns of field-caught Biomphalaria spp., as identified by morphology, were hourly observed over a ten day period and showed that Biomphalaria stanleyi produced significantly more cercariae than Biomphalaria sudanica....... Biomphalaria stanleyi was a more permissive host. After ascertaining appropriate conditions for infection of laboratory mice, 28 groups of between 5 and 6 naïve mice were placed in floatation cages at four suspected shoreline transmission sites for a 30 minute period of exposure. Eight weeks later, mice (n=142...

  19. Determination of Trophic State Changes with Diel Dissolved Oxygen: A Case Study in a Shallow Lake.

    Science.gov (United States)

    Xu, Zhen; Xu, Y Jun

    2015-11-01

    Current trophic state indices (TSI) have been reported to have limitations in assessing changes in eutrophication status of shallow waters. This study aimed to use intensive measurements on dissolved oxygen (DO) to improve the determination of tropic state changes. The authors deployed an environment monitoring buoy in a eutrophic shallow lake and recorded water temperature, DO, and chlorophyll-a concentrations at 15-minute intervals for two 1-year periods: from August 2008 to July 2009 and from August 2013 to July 2014. In addition, they recorded water levels over the same periods and collected water samples for nutrient analysis. The authors analyzed the high-time resolution DO records, compared the diel DO trends between the two 1-year periods, and proposed a new TSI using DO. They found that analyzing the change in diel DO ranges can improve commonly used methods for classifying trophic states and assessing the change of eutrophication status of waterbodies.

  20. The use of oxygen isotopic composition to study water dynamics in Amazon floodplain lakes

    International Nuclear Information System (INIS)

    Martinelli, L.A.; Mortatti, J.; Victoria, R.L.; Matsui, E.

    1989-01-01

    The lakes formed in the Amazon floodplain play a key role in sustaining the highest populational density in the Amazon Basin because of its high primary productivity. The water volume in these lakes vary greatly during the year and possible water sources are the feeding river during high water state of the hydrographs and local inputs from its drainage basin. As these sources are chemically distinct, to understand the nutrient dynamics in these lakes, it is very important to know the relative water contribution of different water sources. In this paper we use 18 O as a conservative to know the water sources for the lakes and our hypothesis is that: 1) In the high water stage lake water is derived predominantly from its feeding river. Therefore their δ 18 O should be similar. 2) In the low water stage lake water is a mixture of watershed and last flood event waters. In this case, lake δ 18 O should be indicative of the relative contribution of each source. To test this hypothesis we assume a two end member mixing a model. If the 18 O isotopic composition of these two sources are known the relative contribution of each source may be calculated by isotopic dilution equation. The first step in this work was to know the 18 O isotopic composition of the lakes and feeding rivers and its spatial and temporal variability. Clearly the δ 18 O signal in the lakes of Amazon varzea is controlled by the 18 O content of the feeding river. But there is a consistent pattern in the 18 O enrichment of the lakes versus the feeding rivers, which is most pronounced on low water period. Our initial hypothesis requires that this water be of local drainage basin origin. Although it was not possible to measure the isotopic composition of local drainage water, indirect measurement suggest that this could be the case. (author). 17 refs, 4 figs, 2 tabs

  1. Forest cover correlates with good biological water quality. Insights from a regional study (Wallonia, Belgium).

    Science.gov (United States)

    Brogna, D; Dufrêne, M; Michez, A; Latli, A; Jacobs, S; Vincke, C; Dendoncker, N

    2018-04-01

    Forested catchments are generally assumed to provide higher quality water in opposition to agricultural and urban catchments. However, this should be tested in various ecological contexts and through the study of multiple variables describing water quality. Indeed, interactions between ecological variables, multiple land use and land cover (LULC) types, and water quality variables render the relationship between forest cover and water quality highly complex. Furthermore, the question of the scale at which land use within stream catchments most influences stream water quality and ecosystem health remains only partially answered. This paper quantifies, at the regional scale and across five natural ecoregions of Wallonia (Belgium), the forest cover effect on biological water quality indices (based on diatoms and macroinvertebrates) at the riparian and catchment scales. Main results show that forest cover - considered alone - explains around one third of the biological water quality at the regional scale and from 15 to 70% depending on the ecoregion studied. Forest cover is systematically positively correlated with higher biological water quality. When removing spatial, local morphological variations, or population density effect, forest cover still accounts for over 10% of the total biological water quality variation. Partitioning variance shows that physico-chemical water quality is one of the main drivers of biological water quality and that anthropogenic pressures often explain an important part of it (shared or not with forest cover). The proportion of forest cover in each catchment at the regional scale and across all ecoregions but the Loam region is more positively correlated with high water quality than when considering the proportion of forest cover in the riparian zones only. This suggests that catchment-wide impacts and a fortiori catchment-wide protection measures are the main drivers of river ecological water quality. However, distinctive results from the

  2. Quantifying foliar responses of white ash to ozone and simulated acid precipitation: an assessment proposal for forest exposure studies

    Science.gov (United States)

    Leon S. Dochinger; Keith F. Jensen; Keith F. Jensen

    1990-01-01

    Seedlings represent an important linkage for assessing the effect of air pollution on forests. This study examines the foliar responses of white ash seedlings to ozone and acid precipitation as a means of identifying atmospheric deposition effects on forests.

  3. Joining Criteria for Harmonizing European Forest Available for Wood Supply Estimates. Case Studies from National Forest Inventories

    Directory of Open Access Journals (Sweden)

    Christoph Fischer

    2016-05-01

    Full Text Available For national and international reporting on forest available for wood supply (FAWS, harmonized data are needed. This information is required as forests provide goods for various sectors like the timber industry or the bioenergy sector. The effect of applying different thresholds to the three restriction classes (environmental, social and economic restriction within the proposed reference definition for FAWS was evaluated. We applied the reference definition for FAWS to national data sets provided by five European National Forest Inventories using harmonized thresholds. The effects on FAWS area and growing stock were evaluated for each restriction and threshold. All countries within this study could report on protected areas. Social restrictions were not applied in any country, data on other restrictions are available but definitions vary. The application of common thresholds for restrictions proved difficult as effects vary between countries. The economic restriction is the most challenging to assess as many countries do not have corresponding data for direct calculation of, e.g., harvesting costs. Using proxies for harvesting costs was difficult, as common thresholds may not be applied in different countries. For standardized reporting, a FAWS definition should be developed that utilizes existing, harmonized indicators to describe restrictions.

  4. Comparative Study of Understorey Birds Diversity Inhabiting Lowland Rainforest Virgin Jungle Reserve and Regenerated Forest

    Directory of Open Access Journals (Sweden)

    Ezyan Nor Hashim

    2013-01-01

    Full Text Available A comparative study of understorey birds inhabiting different habitats, that is, virgin jungle reserve (VJR and regenerated forest (RF, was conducted in Ulu Gombak Forest Reserve and Selangor and Triang Forest Reserve, Negeri Sembilan, Peninsular Malaysia. The objective of this study was to assess the diversity of understorey birds in both habitats and the effects of forest regeneration on the understorey bird community. The mist-netting method was used to capture understorey birds inhabiting both habitats in both locations. Species composition and feeding guild indicated that understorey bird populations were similar in the two habitats. However, the number of secondary forest species such as Little spiderhunter (Arachnothera longirostra in VJR is increasing due to its proximity to RF. This study discovered that RFs in both study areas are not yet fully recovered. However, based on the range of species discovered, the RFs have conservation value and should be maintained because they harbour important forest species such as babblers and flycatchers. The assessment of the community structure of understorey birds in VJR and RF is important for forest management and conservation, especially where both habitats are intact.

  5. Comparative study of understorey birds diversity inhabiting lowland rainforest virgin jungle reserve and regenerated forest.

    Science.gov (United States)

    Nor Hashim, Ezyan; Ramli, Rosli

    2013-01-01

    A comparative study of understorey birds inhabiting different habitats, that is, virgin jungle reserve (VJR) and regenerated forest (RF), was conducted in Ulu Gombak Forest Reserve and Selangor and Triang Forest Reserve, Negeri Sembilan, Peninsular Malaysia. The objective of this study was to assess the diversity of understorey birds in both habitats and the effects of forest regeneration on the understorey bird community. The mist-netting method was used to capture understorey birds inhabiting both habitats in both locations. Species composition and feeding guild indicated that understorey bird populations were similar in the two habitats. However, the number of secondary forest species such as Little spiderhunter (Arachnothera longirostra) in VJR is increasing due to its proximity to RF. This study discovered that RFs in both study areas are not yet fully recovered. However, based on the range of species discovered, the RFs have conservation value and should be maintained because they harbour important forest species such as babblers and flycatchers. The assessment of the community structure of understorey birds in VJR and RF is important for forest management and conservation, especially where both habitats are intact.

  6. The Impact of Nutrient State and Lake Depth on Top-down Control in the Pelagic Zone of Lakes: A Study of 466 Lakes from the Temperate Zone to the Arctic

    DEFF Research Database (Denmark)

    Jeppesen, E.; Jensen, J. P.; Jensen, C.

    2003-01-01

    is unimodally related to TP and is highest in the most nutrient-rich and nutrient-poor lakes and generally higher in shallow than deep lakes, (b) the cascading effect of changes in predator control on phytoplankton decreases with increasing TP, and (c) these general patterns occur with significant variations......%, respectively, at all TP levels. Moreover, deep lakes (more than 6 m) had a higher percentage of Daphnia than shallow (less than 6 m) lakes. The median percentage of Daphnia peaked at 0.15 mg L-1 in shallow lakes and 0.09 mg L-1 in deep lakes. The assumption that fish are responsible for the unimodality...... was supported by data on the abundance of potential planktivorous fish (catch net(-1) night(-1) gill nets with the different mesh sizes [CPUE]). To elucidate the potential cascading effect on phytoplankton, we examined the zooplankton phytoplankton biomass ratio. Even though this ratio was inversely related...

  7. A phytosociological study of riparian forests in Benin (West Africa)

    NARCIS (Netherlands)

    Natta, A.K.; Sinsin, B.; Maesen, van der L.J.G.

    2004-01-01

    Floristic ordination and classification of riparian forests in Benin were derived from a comprehensive floristic inventory. TWINSPAN classification and DCA analysis of a data set of 818 plant species and 180 releve's yielded 12 plant communities. Importance of waterways, relief, topography, latitude

  8. Logging activities in mangrove forests: A case study of Douala ...

    African Journals Online (AJOL)

    Administrator

    these forest ecosystems in relation with the climatic chan- ges and the rising of the sea levels suggest their expan- sion, if the ... The climate is of the particular equatorial type called “Cameroonian” (Din et al., 2002) marked by a ..... Apart from the geomorphology which limits the mangroves extension in the Cameroon estuary ...

  9. Anthropogenic activities affecting Arreo Lake (N Spain) during the last 2500 years

    Science.gov (United States)

    Corella, J.; Valero-Garces, B. L.; Stefanova, I.; El Amrani, A.; Morellón, M.; Rico, E.; González-Sampériz, P.; Moreno-Caballud, A.; Giralt, S.; Sigro, J.

    2010-12-01

    Arreo Lake is a small (288 ha surface area) karstic lake 25 m deep located at the northwestern edge of the Ebro Basin (NE Spain). The integration of sedimentary facies, element geochemistry, mineralogy, and biological proxies (pollen and diatoms), together with a robust chronological model provided by 15 AMS radiocarbon dating, 137Cs analyses, and varve counting, permitted a reconstruction of the main phases of anthropogenic activity affecting the Arreo Lake dynamic in the context of the climate variability in the Iberian Peninsula during the last two millennia. A high-resolution study of the lacustrine facies and diatoms, combined with their detailed comparison with recent regional instrumental climatic data (1952-2007), limnological monitoring of the lake (1992-2008), and recent land-use changes affecting the lake watershed show the strong influence of human activities in lake dynamics during the last 60 years. The main impacts are a large increase in sediment delivery to the lake after the 1980s, fluctuations in lake level caused by water extraction for irrigation, and changes in the mixing status of the lake. Littoral and distal sediment cores record the long history of the use of natural resources (salt, water, forest and farming) and their significant impacts in the lake during the last 2500 years. Periods of higher anthropogenic activities linked to increased salt production in the nearby Salinas de Añana during the Roman Period and the Early Middle Ages were coincident with deforestation and increased sediment delivery to the lake. The Modern period was characterized by an abrupt increase in the sedimentation rate. Forest expansion and reduced clastic input to the lake were synchronous with documented depopulation of the area during the Late Middle Ages and the 20th century. The synergy between climate and human activities is shown by the correspondence of increased human pressure and more favourable climate conditions, such as it is recorded during the

  10. Vegetation and landscape around Lake Montcortès (Catalan pre-Pyrenees as a tool for palaeoecological studies of lake sediments

    Directory of Open Access Journals (Sweden)

    Mercadé, A.

    2013-12-01

    Full Text Available Lake Montcortès (42º 19′ N, 0º 59′ E; 1027 m elevation is an excellent target for high-resolution palaeoecological studies because its annually-laminated sediments extending back to the early-middle Holocene. The detailed knowledge of present vegetation patterns around the lake and the pollen they release to lake sediments is essential for a reliable interpretation of past vegetation dynamics. This study aims to identify and map the vegetation types currently growing around the lake. For this purpose, a quadrangular area of ca. 48 ha was defined. The floristic study resulted in a catalogue of 534 species. Vegetation analysis was based on 42 phytosociological inventories used to synthesise and map the relevant plant landscape units. As a result, we obtained 52 vegetation units as expressions of the CORINE habitats previously defined for Catalonia. Each of these habitats was described in floristic, physiognomic, phytogeographic, environmental and human-use terms. The next step will be the palynological study of the more representative species of the described vegetation types, as a means to optimise future palynological interpretations.El lago de Montcortès (42º 19′ N, 0º 59′ E; 1027 m altitud posee sedimentos con laminaciones anuales, ideales para estudios paleoecológicos de alta resolución. Para el análisis palinológico de estos sedimentos, es necesario conocer en detalle la vegetación local, como fuente del polen sedimentario. El objetivo de este estudio es reconocer y cartografiar los tipos de vegetación presentes alrededor del lago, para lo cual se delimitó un área rectangular de unas 48 ha. Del estudio florístico de este espacio resultó un catálogo de 534 especies, que sirvió de base para el análisis de vegetación. Para ello, se llevaron a cabo 42 inventarios fitosociológicos, que se utilizaron para elaborar una síntesis del paisaje vegetal mediante cartografía digital. Como resultado, se obtuvieron 52 unidades

  11. Tongass National Forest Transportation System Opportunity Study : Final Report for Hoonah and Wrangell Ranger Districts.

    Science.gov (United States)

    2008-07-01

    Tongass National Forest (NF) is in Southeast Alaska, a region rich in natural and cultural resources, which is currently undergoing significant economic change. This study examines how the existing assets of the Tongass NF's transportation system can...

  12. Where to find weather and climatic data for forest research studies and management planning.

    Science.gov (United States)

    Donald A. Haines

    1977-01-01

    Forest-range research or operational study designs should include the possible effects of weather and climate. This document describes the meteorological observational networks, the data available from them, and where the information is stored.

  13. Holocene history of a lake filling and vegetation dynamics of the Serra Sul dos Carajás, southeast Amazonia.

    Science.gov (United States)

    Guimarães, José T F; Sahoo, Prafulla K; Souza-Filho, Pedro W M; Figueiredo, Mariana M J Costa DE; Reis, Luiza S; Silva, Marcio S DA; Rodrigues, Tarcísio M

    2017-07-24

    Down-core changes in sedimentary facies, elemental geochemistry, pollen, spore, δ13C, δ15N and radiocarbon records from a filled lake, named R4, of the Serra Sul dos Carajás were used to study the relationship between the paleomorphological and paleoecological processes and their significance for Holocene paleoclimatology of the southeast Amazonia. The sediment deposition of the R4 lake started around 9500 cal yr BP. Increase of detrital components from 9500 to 7000 cal yr BP suggests high weathering of surrounding catchment rocks and soils, and deposition into the lake basin under mudflows. At that time, montane savanna and forest formation were already established suggesting predominance of wet climate. However, from 7000 to 3000 cal yr BP, a decline of detrital input occurred. Also, forest formation and pteridophytes were declined, while palms and macrophytes were remained relatively stable, indicating that water levels of the lake is likely dropped allowing the development of plants adapted to subaerial condition under drier climate conditions. After 3000 cal yr BP, eutrophication and low accommodation space lead to high lake productivity and the final stage of the lake filling respectively, and forest formation may has acquired its current structure, which suggests return of wetter climate conditions.

  14. Survey of artisanal fishing gear and craft. A case study of Kainji Lake lower basin, Nigeria

    OpenAIRE

    Ogundiwin, Damilare Ibukun

    2014-01-01

    Despite the considerable importance of artisanal fishing in Kainji Lake lower basin, knowledge about gear and craft being used is deficient and outdated. Little is also known as to why fishermen adopted the diverse fishing gear and craft they use in the Lake, as well as the relationship of these input factors to the socio-economic status of the fishermen and ecology of the lake. To address these issues, a survey of sixty (60) artisanal fishers and twelve (12) village leaders drawn from 12 sel...

  15. Natural forest fires and controlled burning - a study of the literature

    International Nuclear Information System (INIS)

    Hoernsten, L.; Nohlgren, E.; Aldentun, Y.

    1995-01-01

    A study of the literature was made to elucidate the history of forest fires in Sweden. Both the frequency of natural forest fires and the extent of controlled burning as a forest-management technique were examined. The literature revealed that natural forest fires occurred every 40 to 160 years, depending on the type of site and the climatic conditions. Natural forest fires are an unusual occurrence nowadays, mainly thanks to effective fire-fighting methods but also because of the reduction in the quantity of combustible materials left in the stands in modern forestry practice. The report describes the factors influencing the occurrence and frequency of forest fires and the impact these have on flora and fauna. Controlled burning has a long history of use as a method of site preparation prior to natural regeneration. Peak usage of the method occurred in the 1950s and 1960s, since when it has steadily declined. An account is given of the methods used for controlled burning. In parallel with the study, we conducted a questionnaire survey among forest enterprises to identify current interest in controlled burning. The techniques used and the costs involved are discussed. In addition to Sweden, we also looked at controlled burning in Canada, Finland and the USA. Finland is closest to Sweden when it comes to the history of controlled burning and the current interest in fire for conservation purposes. 103 refs, 18 figs

  16. Willingness to pay for ecosystem conservation in Alaska's Tongass National Forest: a choice modeling study

    Directory of Open Access Journals (Sweden)

    Evan E. Hjerpe

    2016-06-01

    Full Text Available Forest ecosystems contribute to human welfare in important ways, but because of the nonmarket nature of many of the goods and services produced, both markets and governments fail to optimize their production commensurate with their economic and ecological significance. Despite the recent proliferation of nonmarket environmental valuation in the literature, the incorporation of nonmarket values into public forest decision making has been limited by institutional and methodological barriers. To address this disconnect, we conducted a case study to quantify conservation values for the Tongass National Forest in a manner conducive for public forest planning. A choice experiment featuring proposed forest management alternatives with changes in critical attributes relative to their levels in the status quo was used to generate the requisite data. Econometric analysis suggests that Alaskans have strong preference for conservation management, including both preservation and ecological restoration, over status quo or exploitation management. However, there is significant heterogeneity among Alaskans in terms of bias toward the status quo depending on their socioeconomic characteristics, e.g., gender, age, place of residence, household income, whether or not they have dependent children. The findings of this study can be helpful to forest managers in the preparation of resource management plans consistent with maximization of total economic value of forest ecosystem services.

  17. Application of synchrotron X-ray fluorescent analysis to studies of the records of paleoclimates of Eurasia stored in the sediments of Lake Baikal and Lake Teletskoye

    International Nuclear Information System (INIS)

    Goldberg, E.L.; Grachev, M.A.; Phedorin, M.A.; Kalugin, I.A.; Khlystov, O.M.; Mezentsev, S.N.; Azarova, I.N.; Vorobyeva, S.S.; Zheleznyakova, T.O.; Kulipanov, G.N.; Kondratyev, V.I.; Miginsky, E.G.; Tsukanov, V.M.; Zolotarev, K.V.; Trunova, V.A.; Kolmogorov, Yu.P.; Bobrov, V.A.

    2001-01-01

    Multi-element SRXRF of sediments of Lake Baikal (East Siberia) with samples taken at 10 cm intervals from a core spanning the last 250 ky revealed nine peaks of 'warm' signals like Sr/Ba(Rb,Cs) and U/Th corresponding to Oceanic Isotope Stages 1,3,5a,5c,5e,7 and 9, and six peaks of 'cold correlator' corresponding to OIS 2,4,5d,6 and 8. A slab (1500-2200 mm below the sediment surface) taken from another core was studied by scanning SRXRF. This interval corresponds to the Siberian Karga interstadial (OIS3, 24-58 ky BP). It hosted two peaks of diatom algae frustulles, indicators of warmer climates. The scanning was performed at a temporal resolution of ca. 50 yr. Ratios of concentrations like Sr/Rb(Ba,Cs,Ti,Fe) (Nucl. Instr. and Meth. A 448(1-2) (2000) 384; Nucl. Instr. and Meth. A 448 (1-2) (2000) 400) appeared to be more sensitive proxies of warm climates, compared to total diatoms, and revealed at least six pronounced cycles of abrupt warming and cooling episodes, each lasting a few millennia. These fluctuations may reflect a response of the catchment basin of the Lake Baikal to abrupt global climate cycles recorded in the ice of Greenland and in the sediments of North Atlantic (Nature 364 (1993) 142; Science 278 (1997) 1257; Science 288 (2000) 128). SRXRF applied to the sediments of Lake Teletskoye (West Siberia, Altai Mountains) of the last 600 yr provided a temporal resolution of 1.2-1.8 yr. The profiles of a few elements like K, Ca, Ti, Fe, V revealed oscillations with a periodicity of 9.4 yr over the time interval between years 1400 and 1600. Oscillations faded out after the cooling of 1600-1700 (The Maunder interval). Periodic oscillations between years 1400 and 1600 seem to correspond to periodic changes in the height of oceanic tides (9 yr (PNAS 94 (1997) 8321; PNAS 97 (2000) 3814)) rather than to the solar activity cycles (periodicity of 11 yr)

  18. CHANGING LIVELIHOODS AND THE ENVIRONMENT ALONG LAKE NYASA, TANZANIA

    OpenAIRE

    NINDI, J. Stephen

    2007-01-01

    People living along the Lake Nyasa shore, Tanzania relies largely on fishing and cultivation of cassava and rice. The fishing industry has shaped the sociopolitical organisation of local people. The Matengo Highlands and Livingstone Mountains act as catchments of Lake Nyasa. The relationship between the land use in the catchments, Nyasa people's livelihood and the lake fishing environment is intriguing, because of the belief that catchment forests and streams help make the lake basin a rich h...

  19. Community-based Forest Resources Management in Nigeria: Case study of Ngel Nyaki Forest Reserve, Mambilla Plateau, Taraba State, Nigeria

    Directory of Open Access Journals (Sweden)

    T.I. Borokini

    2012-05-01

    Full Text Available In Nigeria, human communities are found within or beside forest ecosystems, depending onthese ecosystems for survival. Their forest exploitation is considered a threat to conservation efforts,leading to constant conflicts between Government, law enforcement agencies and the communities. Thebest solution is a win-win system of participatory community-based forest resources management, inwhich the communities are regarded as stakeholders rather than as threats. This paper explains theadoption of this approach in Ngel Nyaki Forest Reserve, Mambilla Plateau, where the communities weretrained in establishment and management of forest plantations with readily available market for theirtimber; employment for some of the community youths as well as community development projects.This paper calls for the adoption of this system in other protected areas in Nigeria, while theGovernment should provide basic amenities for the communities as alternatives to those forest products.Keywords: Community-based forest management, Ngel Nyaki Forest Reserve, Protected areas, Nigeria.

  20. Mapping Dynamics of Inundation Patterns of Two Largest River-Connected Lakes in China: A Comparative Study

    OpenAIRE

    Guiping Wu; Yuanbo Liu

    2016-01-01

    Poyang Lake and Dongting Lake are the two largest freshwater lakes in China. The lakes are located approximately 300 km apart on the middle reaches of the Yangtze River and are differently connected through their respective tributary systems, which will lead to different river–lake water exchanges and discharges. Thus, differences in their morphological and hydrological conditions should induce individual lake spatio-temporal inundation patterns. Quantitative comparative analyses of the dynam...

  1. Amazonian landscapes and the bias in field studies of forest structure and biomass.

    Science.gov (United States)

    Marvin, David C; Asner, Gregory P; Knapp, David E; Anderson, Christopher B; Martin, Roberta E; Sinca, Felipe; Tupayachi, Raul

    2014-12-02

    Tropical forests convert more atmospheric carbon into biomass each year than any terrestrial ecosystem on Earth, underscoring the importance of accurate tropical forest structure and biomass maps for the understanding and management of the global carbon cycle. Ecologists have long used field inventory plots as the main tool for understanding forest structure and biomass at landscape-to-regional scales, under the implicit assumption that these plots accurately represent their surrounding landscape. However, no study has used continuous, high-spatial-resolution data to test whether field plots meet this assumption in tropical forests. Using airborne LiDAR (light detection and ranging) acquired over three regions in Peru, we assessed how representative a typical set of field plots are relative to their surrounding host landscapes. We uncovered substantial mean biases (9-98%) in forest canopy structure (height, gaps, and layers) and aboveground biomass in both lowland Amazonian and montane Andean landscapes. Moreover, simulations reveal that an impractical number of 1-ha field plots (from 10 to more than 100 per landscape) are needed to develop accurate estimates of aboveground biomass at landscape scales. These biases should temper the use of plots for extrapolations of forest dynamics to larger scales, and they demonstrate the need for a fundamental shift to high-resolution active remote sensing techniques as a primary sampling tool in tropical forest biomass studies. The potential decrease in the bias and uncertainty of remotely sensed estimates of forest structure and biomass is a vital step toward successful tropical forest conservation and climate-change mitigation policy.

  2. A Comparative Study of the Soil Fauna in forests and cultivated land on sandy soils in Suriname

    NARCIS (Netherlands)

    Drift, van der J.

    1963-01-01

    1. In the coastal area of Suriname the soil and surface fauna were studied in various types of agricultural land, and compared with the fauna in the adjacent forests. 2. In primeval forest the soil macroarthropods are less numerous than in secondary forest (Formicidae excluded). They range generally

  3. Does the Lack of Reference Ecosystems Limit Our Science? A Case Study in Nonnative Invasive Plants as Forest Fuels

    Science.gov (United States)

    Alison C. Dibble; Catherine A. Rees

    2005-01-01

    In forest experiments the problem of inadequate controls often arises. True controls might not be required in case studies, comparisons along an environmental gradient, or comparisons of multiple treated and untreated areas. In a recent characterization of fuels in invaded and uninvaded forest conditions for four forest types at 12 locations in Maine, Maryland,...

  4. Are community-based forest enterprises in the tropics financially viable? Case studies from the Brazilian Amazon

    Science.gov (United States)

    Shoana Humphries; Thomas P. Holmes; Karen Kainer; Carlos Gabriel Goncalves Koury; Edson Cruz; Rosana de Miranda Rocha

    2012-01-01

    Community-based forest management is an integral component of sustainable forest management and conservation in the Brazilian Amazon, where it has been heavily subsidized for the last ten years. Yet knowledge of the financial viability and impact of community-based forest enterprises (CFEs) is lacking. This study evaluates the profitability of three CFEs in the...

  5. Wood Decomposition of Cyrilla racemiflora (Cyrillaceae) in Puerto Rican Dry and Wet Forests: A 13-year Case Study.

    Science.gov (United States)

    Juan A. Torres; Grizelle Gonzalez

    2005-01-01

    We studied the decomposition of Cyrilla racemiflora logs over a 13-yr period in tropical dry and wet forests in Puerto Rico. The mean mass loss, ratio of soft to hard wood, nutrient concentrations, and the diversity of wood-inhabiting organisms were greater in logs decomposing in the dry forest than in the wet forest. Termites were also more abundant in the logs...

  6. Ecological lessons from long-term studies in experimental forests: ponderosa pine silviculture at Pringle Falls Experimental Forest, central Oregon

    Science.gov (United States)

    Andrew. Youngblood

    2011-01-01

    The United States Department of Agriculture (USDA) Forest Service celebrated the 100th anniversary of its network of experimental forests in 2008. For a century, the network of experimental forests have contributed immensely, both in the US and around the world, to the practical understanding of the environment and to the formation of management approaches and policies...

  7. Social participation and oak forest conservation: Paipa and Duitama study case

    International Nuclear Information System (INIS)

    Escobar Torres, Vivian Constanza; Palacio Tamayo, Dolly Cristina

    2010-01-01

    Social dynamics within social participation is a crucial issue for the accomplishment of forest conservation. In order to contribute to this field, a study of 31 institutional and community organized actors' cooperative practices, within forest conservation processes in Paipa and Duitama, located at the oak forests conservation corridor Guantiva, La Rusia, Iguaque in Colombia, was made, applying Social Network Analysis (SNA). Particularly, this article inquiry is about models of participation of these actors within the period of 2004-2008, looking at their projects and actions as management practices of forest conservation. The research questions were how social participation is included and understood in the conservation of these oak forests, observing cooperative practices amongst this set of actors, at local level. The results are related with the structural patterns of co-participation established amongst these actors within each other's projects and actions and the impact of those in the aim of forest conservation at local level, regarding power relations and its impact on forest conservation.

  8. Studies on heavy metal accumulation in aquatic macrophytes from Sevan (Armenia) and Carambolim (India) lake systems

    Digital Repository Service at National Institute of Oceanography (India)

    Vardanyan, L.G.; Ingole, B.S.

    of these macrophytes in accumulation of toxic metals and controlling the heavy metal pollution and suggesting the remedial measures, if any, for the preservation and restoration of lake ecosystem. Inductively Coupled Plasma-Atomic Emission Spectrometric (ICP...

  9. Repeated Fish Removal to Restore Lakes: Case Study of Lake Væng, Denmark—Two Biomanipulations during 30 Years of Monitoring

    Directory of Open Access Journals (Sweden)

    Martin Søndergaard

    2017-01-01

    Full Text Available Biomanipulation by fish removal has been used in many shallow lakes as a method to improve lake water quality. Here, we present and analyse 30 years of chemical and biological data from the shallow and 16 ha large Lake Væng, Denmark, which has been biomanipulated twice with a 20-year interval by removing roach (Rutilus rutilus and bream (Abramis brama. After both biomanipulations, Lake Væng shifted from a turbid, phytoplankton-dominated state to a clear, water macrophyte-dominated state. Chlorophyll a was reduced from 60–80 μg·L−1 to 10–30 μg·L−1 and the coverage of submerged macrophytes, dominated by Elodea canadensis, increased from <0.1% to 70%–80%. Mean summer total phosphorus was reduced from about 0.12 to 0.07 mg·L−1 and total nitrogen decreased from 1.0 to 0.4 mg·L−1. On a seasonal scale, phosphorus and chlorophyll concentrations changed from a summer maximum during turbid conditions to a winter maximum under clear conditions. The future of Lake Væng is uncertain and a relatively high phosphorus loading via the groundwater, and the accumulation of a mobile P pool in the sediment make it likely that the lake eventually will return to turbid conditions. Repeated fish removals might be a relevant management strategy to apply in shallow lakes with a relatively high external nutrient loading.

  10. Geologic Map of Mount Mazama and Crater Lake Caldera, Oregon

    Science.gov (United States)

    Bacon, Charles R.

    2008-01-01

    Crater Lake partly fills one of the most spectacular calderas of the world, an 8-by-10-km basin more than 1 km deep formed by collapse of the volcano known as Mount Mazama (fig. 1) during a rapid series of explosive eruptions about 7,700 years ago. Having a maximum depth of 594 m, Crater Lake is the deepest lake in the United States. Crater Lake National Park, dedicated in 1902, encompasses 645 km2 of pristine forested and alpine terrain, including the lake itself, virtually all of Mount Mazama, and most of the area of the geologic map. The geology of the area was first described in detail by Diller and Patton (1902) and later by Williams (1942), whose vivid account led to international recognition of Crater Lake as the classic collapse caldera. Because of excellent preservation and access, Mount Mazama, Crater Lake caldera, and the deposits formed by the climactic eruption constitute a natural laboratory for study of volcanic and magmatic processes. For example, the climactic ejecta are renowned among volcanologists as evidence for systematic compositional zonation within a subterranean magma chamber. Mount Mazama's climactic eruption also is important as the source of the widespread Mazama ash, a useful Holocene stratigraphic marker throughout the Pacific Northwest, adjacent Canada, and offshore. A detailed bathymetric survey of the floor of Crater Lake in 2000 (Bacon and others, 2002) provides a unique record of postcaldera eruptions, the interplay between volcanism and filling of the lake, and sediment transport within this closed basin. Knowledge of the geology and eruptive history of the Mount Mazama edifice, greatly enhanced by the caldera wall exposures, gives exceptional insight into how large volcanoes of magmatic arcs grow and evolve. Lastly, the many smaller volcanoes of the High Cascades beyond the limits of Mount Mazama are a source of information on the flux of mantle-derived magma through the region. General principles of magmatic and eruptive

  11. Bagley Fire Sediment Study: Shasta-Trinity National Forest, Eastern Klamath Mountains, Northern California

    Science.gov (United States)

    Bachmann, S.; De La Fuente, J. A.; Hill, B.; Mai, C.; Mikulovsky, R. P.; Mondry, Z.; Rust, B.; Young, D.

    2013-12-01

    The US Forest Service is conducting a study of sediment mobilization, transport, and deposition on the Bagley Fire, which burned about 18,000 hectares in late summer, 2012, on the Shasta-Trinity National Forest, south of McCloud, CA. The fire area is in steep terrain of the Eastern Klamath Mountains that are underlain primarily by metasedimentary rock. The watersheds affected drain into the headwaters of Squaw Creek, along with small streams tributary to the McCloud and Pit Rivers, all of which flow into Shasta Lake Reservoir. In November and December of 2012, intense storms occurred over the fire area with estimated return intervals of 25-50 years, based on 4-day storm totals in ranging from 38 to 56 cm. The Squaw Creek storm response was unique for this area, in that it remained turbid for about 2 months following the storms. Subsequent small storms through June, 2013 have also generated prolonged turbidity. This may be attributable to the remobilization of fine particles temporarily stored in the channel network. Preliminary observations from field reconnaissance include the following: a) Erosional processes were dominated by sheet, rill, and gully erosion, and the resulting sediment delivered to channels was rich in fine particles and gravels; b) Landslides were infrequent, and as a result, a limited amount of large rock and logs were delivered to channels; c) Sediment laden flows occurred in most burned low order channels, but classic debris flows, those scouring all vegetation from channel bottoms, were very uncommon; d) Most road stream crossing culverts failed in high severity burn areas; e) Low gradient stream reaches in Squaw Creek were aggraded with fine sediment; f) Sustained high levels of turbidity occurred in the main stem of Squaw Creek. The goals of this study are to characterize relative roles of surface erosion, landslides, and debris flows in delivering sediment to streams after the fire, and if possible, to develop a rough sediment budget

  12. Stable isotopes, δ18O and δ2H, in the study of water balance of Lake Massoko, Tanzania: Investigation of the exchange between lake and underground water

    International Nuclear Information System (INIS)

    Bergonzini, L.; Gibert, E.; Winckel, A.

    2002-01-01

    Full text: The stable oxygen and deuterium isotope compositions of a lake depend upon its water balance. Therefore the balance equations of stable isotopes, which imply calculation of the composition of evaporating moisture α E , provide information for assessing the water balance. In most cases, this approach is used to investigate the relationships between lakes and groundwater. Lake Massoko (8 deg. 20'S, 33 deg. 45'E, 870 m.a.s.l.) is a freshwater maar-lake without surface outlet. The lake surface and its runoff area cover 0.38 and 0.55 km 2 respectively. In contrast with the mean annual rainfall in the other parts of south Tanzania (1000-1200 mm y -1 ), the presence of Lake Malawi to the South, and the high ranges to the North (Mounts Poroto, Rungwe and Livingstone) imply local climatic features. Air masses overloaded with humidity bypassing Lake Malawi are submitted, especially in April, to ascending currents, producing rainfalls up to 2450 mm y -1 over Massoko area. Because of the evaporation rate from the lake's surface (around 2100 mm y -1 ) and without taking into account the runoff from the drainage basin, hydrological balance is positive and imply underground lost. One of most difficult points in the establishment of the isotope balances is the calculation of the composition of the evaporated water (δ E ), which requires an estimation of the isotopic composition of the water vapour in the atmosphere over the lake (δ Atm ). Without direct measurements, two ways can be used for the determination of the vapour composition (i) equilibrium with precipitation and reconstitution from them, or (ii) calculation from the balances of a terminal lake of the region. Both approaches are presented and compared, but only the second one allows physical solutions. δ Atm determined from Lake Rukwa hydrological and isotope balances has been used to calculate values for δ E over Lake Massoko. The estimation of δ Atm obtained from Lake Rukwa budgets presents a deuterium

  13. Use of medicinal plants for human health in Udzungwa Mountains Forests: a case study of New Dabaga Ulongambi Forest Reserve, Tanzania

    Directory of Open Access Journals (Sweden)

    Kitula Rukia A

    2007-01-01

    Full Text Available Abstract The dependence of local people on plant medicine from natural forests has a long tradition in Tanzania and is becoming increasingly popular among rural and urban communities due to among others increase in living costs. The study on utilization of medicinal plants for meeting heath care needs was carried out between March 2001 and March 2002 in New Dabaga Ulongambi Forest Reserve, Tanzania. The study aimed at generating necessary data for the Udzungwa Mountains Forest Management project to draft sound Joint Forest Management plans. Specific objectives of the study among others were to assess knowledge associated with utilization of medicinal plants for health care needs as well as factors associated in using plant medicines in the study area. A questionnaire survey, market survey and literature review were used to collect information. Tools used for data analysis were Statistical Packages for Social Science and content analysis. A total of 45 plant species were documented curing about 22 human diseases. Medicinal plants were readily available throughout the year and plentiful in the forest reserve. Roots and leaves were the plant parts harvested for medicinal purposes. Processing of plant medicines involved boiling, pounding, soaking in water and chewing. Distance to health facility, income level of the household and beliefs contributed to the use of plant medicines. The study concluded that medicinal plants play an important role in providing primary health care to the rural communities. It is recommended that in achieving joint forest management (JFM, villagers adjacent to the forest reserve should be sensitised on the importance of JFM through seminars, workshops, drama, school songs or video show. During the development of a joint draft management plan, villagers as an informal institution must define their priority needs of use of parts of the forest in collaboration with the Udzungwa Mountains Forest Management project.

  14. Conflict management in natural resources : a study of land, water and forest conflicts in Nepal

    OpenAIRE

    Upreti, B.R.

    2001-01-01

    This book is based on the research into natural resource (NR)-conflict carried out between 1997 and 2000 in the Dolakha district of central Nepal, and in several reference sites around the country. The study focussed especially on land, water and forest/pasture conflicts and their resolution/management practices. Five inter-connected conflict cases related to irrigation, Guthi -land, spring water source and forest-pasture land were examined and compared with elev...

  15. Dispersal of forest insects

    Science.gov (United States)

    Mcmanus, M. L.

    1979-01-01

    Dispersal flights of selected species of forest insects which are associated with periodic outbreaks of pests that occur over large contiguous forested areas are discussed. Gypsy moths, spruce budworms, and forest tent caterpillars were studied for their massive migrations in forested areas. Results indicate that large dispersals into forested areas are due to the females, except in the case of the gypsy moth.

  16. A study of the river basins and limnology of five humic lakes on Chiloé Island Estudio de la cuenca y limnología en cinco lagos húmicos de la Isla Chiloé

    OpenAIRE

    L. VILLALOBOS; O. PARRA

    2003-01-01

    From November 1996 to October 1997, the river basins of five humic lakes on Chiloé Island were studied monthly: Lakes Natri, Tepuhueico, Tarahuín, Huillinco and Cucao. The objective of this study was to know the catchment area, river basin and the main physical, chemical and biological characteristics of these humic lakes. The trophic status, the actual loading, and the mass balances of phosphorus and nitrogen were determined in relation to anthropogenic activities. Lakes Cucao and Huillinco ...

  17. Policy Recommendation from Stakeholders to Improve Forest Products Transportation: A Qualitative Study

    Directory of Open Access Journals (Sweden)

    Anil Koirala

    2017-11-01

    Full Text Available With recently announced federal funding and subsidies to redevelop vacant mills and the communities they were in, the forest products industry in Maine is poised to gain its momentum once again. One of the important components influencing the cost of delivered forest products is transportation. A recent study in the region has shown that the location and availability of markets along with lack of skilled labor force are the major challenges faced by the forest products transportation sector in Maine. This study was focused on developing a management guideline which included various field level options for improving trucking enterprises in Maine. For this, a qualitative research approach utilizing a case study research tradition was employed, with in-depth semi-structured interviews with professionals directly related to the forest products transportation sector used for data generation. Thirteen semi-structured interviews were conducted, with each being audio recorded and later transcribed verbatim. Interview transcriptions were analyzed using NVivo 11. Suggestions, like increasing benefits to drivers and providing training, were proposed for challenges related to manpower shortage, while the marketing of new forest products and adjustment in some state-level policies were proposed for challenges related to the forest products market condition of the state.

  18. Study on the forest vegetation restoration monitoring using HJ-1A hyperspectral data

    International Nuclear Information System (INIS)

    Chuan, Zhang; Fawang, Ye; Hongcheng, Liu; Haixia, He

    2014-01-01

    In this paper, Xunke County was studied using HJ-1A hyperspectral data for monitoring vegetation restoration after forest fires. The pre-processing procedure including data format conversion, image mosaicing and atmospheric correction. Support vector machine classification was used to perform surface feature identification based on the extracted spectral end-members. On that basis, the image area was divided into seven categories and statistical analysis of classification types was performed. The results showed that HJ-1A hyperspectral data had great potential in fine classification of surface features and the accuracy of classification was 91.8%. The mild and severe fire-affected area extraction provided useful reference for disaster recovery monitoring. Furthermore, the distinction between coniferous forest and broadleaved forest can offer useful information for forest fire prevention and early warning to some extent

  19. Pompton Lakes Photo Gallery

    Science.gov (United States)

    This gallery provides representative photographs of the soil removal and dredging operations within the Pompton Lake Study Area (PLSA) performed starting in 2016 through the present. It will be periodically updated in conjunction with the progress of the

  20. Early Holocene Great Salt Lake

    Science.gov (United States)

    Oviatt, Charles G.; Madsen, David B.; Miller, David; Thompson, Robert S.; McGeehin, John P.

    2015-01-01

    Shorelines and surficial deposits (including buried forest-floor mats and organic-rich wetland sediments) show that Great Salt Lake did not rise higher than modern lake levels during the earliest Holocene (11.5–10.2 cal ka BP; 10–9 14C ka BP). During that period, finely laminated, organic-rich muds (sapropel) containing brine-shrimp cysts and pellets and interbedded sodium-sulfate salts were deposited on the lake floor. Sapropel deposition was probably caused by stratification of the water column — a freshwater cap possibly was formed by groundwater, which had been stored in upland aquifers during the immediately preceding late-Pleistocene deep-lake cycle (Lake Bonneville), and was actively discharging on the basin floor. A climate characterized by low precipitation and runoff, combined with local areas of groundwater discharge in piedmont settings, could explain the apparent conflict between evidence for a shallow lake (a dry climate) and previously published interpretations for a moist climate in the Great Salt Lake basin of the eastern Great Basin.

  1. Impact of community-based natural resource management on household consumption: a case study of Tonle Sap Lake, Cambodia

    OpenAIRE

    Rylida Vong

    2017-01-01

    Community-based natural resource management (CBNRM) is implemented in Tonle Sap Lake (TSL), Cambodia after abolishment of commercial fishing lots in 2001 and 2012. One objective of CBNRM implementation is to reduce poverty of the local communities in TSL. This study aimed to examine the impact of CBNRM on household consumption of fishermen in TSL through Propensity Score Matching method by comparing 248 non-CBNRM households and 223 CBNRM households This study reveals that CBNRM had a negative...

  2. Development in techniques for studying forest roads on peatlands

    International Nuclear Information System (INIS)

    Saarilahti, M.

    1988-01-01

    A light seismic method, a short-pulse radar and a microwave probe are tested in assessing the properties of a forest road constructed on peatland. The light seismic method gave reliable values for estimating the bearing capacity of the road. It was found that bearing capacity was mostly dependent on embankment thickness, but quality of labric might also have an influence. Embankment thickness and peat depth can be measured on the radargram, and some additional information on road bed and peat obtained. The microwave peat probe permits recording of the continuous moisture profile in situ, which improves accuracy of planning

  3. Paper birch (Wiigwaas) of the Lake States, 1980-2010

    Science.gov (United States)

    W. Keith Moser; Mark H. Hansen; Dale Gormanson; Jonathan Gilbert; Alexandra Wrobel; Marla R. Emery; Michael J. Dockry

    2015-01-01

    Data on paper birch (Betula papyrifera L.; wiigwaas in the Ojibwe language), collected by the Forest Inventory and Analysis (FIA) program of the U.S. Forest Service on forested lands in the Great Lakes region (Michigan, Minnesota, and Wisconsin) from 1980 through 2010, are reported. Also presented are results and analysis of a supplemental inventory...

  4. Using MOD16 products for analyzing evapotranspiration and evaporation on the surface of lakes. Case studies in Romania

    Science.gov (United States)

    Stan, Florentina; Madelin, Malika; Zaharia, Liliana

    2017-04-01

    Evapotranspiration and evaporation are some of the most complex atmospheric processes and major components of the water balance. The knowledge of these processes at several spatial and temporal scales has great practical importance in the field of water resources management and agriculture. However, the direct measurement of these parameters is generally a problem, because it requires accuracy and instruments (lysimeters and pans) difficult to install; therefore many equations based on physical processes or vegetation stages have been proposed by different scientists (Thornthwaite, Penman, etc.). The use of remote sensing is a good alternative to estimate the evapotranspiration, by taking advantage of the new generation of Earth Observation Satellites. In recent years, a remote sensing product from the MODerate Resolution Imaging Spectrometer - MOD16 has been developed. The MOD16 algorithm (Mu et al. 2007) combines on the one hand remote sensing data on land cover, albedo, leaf area index and in the other hand radiation, air temperature and vapor pressure deficit data, in order to estimate real evapotranspiration (ET) and potential evapotranspiration (PET), at 1 km2 resolution. Until now the MOD16 products were not used in the Romanian studies, so the product accuracy is unknown. The main objective of this study is to correlate the MOD16 ET and PET products with the evaporation (E) data measured at the surface of some lakes (Căldăruşani, Soleşti, Cinciş), located in different climate and landform conditions in Romania, in order to establish the relationships between those parameters, that could allow estimate indirectly the evaporation, based on the MODIS products. We correlated the daily recorded pan evaporation data with the MOD16 products, by taking into account R2 coefficients. Eight-day cumulative evaporation data from the considered pans was calculated to coincide with the eight-day MOD16 products over 2010 - 2012. A secondary purpose of the paper is to

  5. Preliminary ecological study of plant species of Lokame Natural Forest (Nord Ubangi Province, Democratic Republic of the Congo): A special emphasis on Non-timber Forest Products

    OpenAIRE

    Koto-te-Nyiwa Ngbolua,

    2017-01-01

    A preliminary ecological study with a special emphasis on Non-timber forest products (NTFPs) was conducted between 2014 and 2015 on both anks of Lokame River in Lokame forest. The results showed that the Lokame natural forest has a very rich and diversified in NTFPs. Data collected over a total area of 2 ha identified 20 families and 25 different plant species producing NTFPs and 914 individuals, of which 39% are food, 38% for different uses, 14% for aphrodisiacs and 9% as medicinal. A compar...

  6. Mining and drought in the tropical Andes: a case study of lake Poopó

    Science.gov (United States)

    Zogheib, C.

    2017-12-01

    The respective impacts of mining water withdrawals and El Niño-related droughts on water availability in the Altiplano region of the tropical Andes were investigated. The naturally semi-arid to arid climate of the region is highly vulnerable to the effects of the El Niño Southern Oscillation (ENSO) as well as changes to the Bolivian High upper troposphere circulation. The 2015-2016 El Niño event displayed a maximal Oceanic Niño Index (ONI) of up to 2.2 °C, comparable with the 1998-1999 event, considered as the most severe of the 20th century with a maximal ONI of 2.5 °C. This has severely impacted the Altiplano region. Whereas mining has been found to affect observed water quality in the region, its influence on water availability has not been extensively examined. In light of these observations, the case of Lake Poopó, a water body at the intersection of both these climatic and anthropogenic influences, was further analyzed. The lake was officially declared dry in January 2016 by the Bolivian government. Therefore, a water balance model was implemented for the Lake Titicaca - Río Desaguadero - Lake Poopó - Salar de Coipasa (TDPS) catchment, simulating several possible climatic scenarios. Mines were identified and associated water withdrawals were extrapolated using available processing water consumption data. Long-term climatic trends, as averaged between 1970 and 2010 were used to assess the recovery prospects of the lake. Mining was found to have a very limited impact on water quantity in Lake Poopó, with total mining water withdrawals accounting for 0.2% to 0.4% of the total amount of water flowing into the lake from the Desaguadero River, reduced by only 1%. However, 1998 El Niño-induced drought conditions were found to cause a net yearly reduction in storage of 0.76 m. Under such climatic constraints, it was obtained that 32 months were needed for the lake to dry out from its height of 1.972 m as observed on the 10th of April 2013 and 38 months

  7. Forest fires detection in Indonesia using satellite Himawari-8 (case study: Sumatera and Kalimantan on august-october 2015)

    Science.gov (United States)

    Fatkhuroyan; Wati, Trinah; Panjaitan, Andersen

    2017-01-01

    Forest fires in Indonesia are serious problem affecting widely in material losses, health and environment. Himawari-8 as one of meteorological satellites with high resolution 0,5 km x 0,5 km can be used for forest fire monitoring and detection. Combination between 3, 4 and 6 channels using Sataid (Satellite Animation and Interactive Diagnosis) software will visualize forest fire in the study site. Monitoring which used Himawari-8 data on August, September and October 2015 can detect the distribution of smoke and the extents of forest fire in Sumatera and Kalimantan. The result showed the extent of forest fire can be identified for anticipation in the next step.

  8. Geomagnetic secular variation as recorded in British lake sediments and its application to archaeomagnetic studies

    Science.gov (United States)

    Clelland, Sarah-Jane; Batt, Catherine M.

    2012-03-01

    Lake sediments can play an important role in understanding and reconstructing temporal characteristics of the geomagnetic field, as they potentially offer near continuous high-resolution archives of magnetic information extending throughout the Holocene. To date lake sediment geomagnetic data has typically been excluded from British archaeomagnetic secular variation curves (SVC) due to uncertainties with the acquisition of magnetisation by lake sediments. This paper presents the argument that, with regards to British datasets, the real problem lies with poor chronological control and sets out to illustrate that with British archaeomagnetic data some progress has been made. The results indicate that it is not currently possible to resolve secular variation on a time scale of ˜100 years from published British lake sediment data but more success has been made with data from archaeological sediments. This level of detail has been considered necessary for the incorporation of lake sediment data into the British archaeomagnetic dataset, as the ability to resolve short-term geomagnetic changes is critical for the integration of any dataset into the British SVC. As the latter is predominantly employed to date archaeological architecture and artefacts requires that it has the ability to resolve changes over timescales relevant to human lifetimes. Using currently available data this retrospective critique confirms that, in archaeological sediments, depositional and thermoremanent magnetisation can record the same direction over the same time interval.

  9. Study of the behaviour of transuranics and possible chemical homologues in Lake Michigan water and biota

    International Nuclear Information System (INIS)

    Wahlgren, M.A.; Alberts, J.J.; Nelson, D.M.; Orlandini, K.A.

    1976-01-01

    Concentration factors for Pu, Am and U in Lake Michigan biota are compared to those of a number of stable trace elements that have short residence times in Lake Michigan water. The relative order of uptake for these nuclides in Lake Michigan biota is Am>Pu much>U. Evidence is summarized which suggests that the predominant oxidation state of 239 , 240 Pu in Lake Michigan water is 4+. Concentrations of 239 , 240 Pu in net plankton, filterable particulate matter, sediment trap, and benthic floc samples indicate that sorption by biogenic detritus, and settling of this material, can account for the reduced concentration of 239 , 240 Pu observed in surface waters during summer stratification, but that deposition into the sediments is primarily non-biological. Concentrations of 7 Be, 144 Ce and 137 Cs in sediment trap samples show the effect of spring convective mixing and demonstrate the resuspension of mineral-rich surficial sediments during the summer months. The effect on the concentration of dissolved plutonium in the water column, of varying degrees of resuspension of sedimentary floc, is described using a simple mass-action model. A radiochemical method for the determination of americium and uranium in Lake Michigan environmental samples is also presented. (author)

  10. A preliminary study of the Hg flux from selected Ohio watersheds to Lake Erie

    International Nuclear Information System (INIS)

    Fitzgibbon, T.O.; Berry Lyons, W.; Gardner, Christopher B.; Carey, Anne E.

    2008-01-01

    New measurements of riverine dissolved and particulate Hg fluxes into Lake Erie from 12 northern Ohio watersheds have been determined from samples collected in April 2002 and analyzed using ultra-clean techniques with cold-vapor atomic fluorescence spectrometry. Total Hg concentrations ranged through 2.5-18.5 ng L -1 , with a mean of 10.4 ng L -1 with most Hg in particulate form. Dissolved Hg concentrations ranged through 0.8-4.3 ng L -1 , with a mean of 2.5 ng L -1 . Highest total Hg concentrations were observed in western rivers with primarily agricultural land use and eastern rivers with mixed land use in their watersheds. Total suspended solid concentrations ranged through 10-180 mg L -1 with particulate Hg concentrations ranging through 47-170 ng g -1 , with a mean of 99 ng g -1 . Particulate Hg was similar to published data for central Lake Erie bottom sediments but much lower than for bottom sediments in western Lake Erie. Total Hg concentrations were positively correlated with suspended sediment concentrations and negatively with dissolved NO 3 - concentrations. The total estimated annual Hg fluxes from these rivers into Lake Erie is estimated to be 85 kg, but because only one event was sampled during high flow conditions, this may be an overestimate. This is much lower than previous published estimates of riverine Hg input into Lake Erie

  11. Modeling thermal structure, ice cover regime and sensitivity to climate change of two regulated lakes - a Norwegian case study

    Science.gov (United States)

    Gebre, Solomon; Boissy, Thibault; Alfredsen, Knut

    2013-04-01

    A great number of river and lakes in Norway and the Nordic region at large are regulated for water management such as hydropower production. Such regulations have the potential to alter the thermal and hydrological regimes in the lakes and rivers downstream impacting on river environment and ecology. Anticipated changes as a result of climate change in meteorological forcing data such as air temperature and precipitation cause changes in the water balance, water temperature and ice cover duration in the reservoirs. This may necessitate changes in operational rules as part of an adaptation strategy for the future. In this study, a one dimensional (1D) lake thermodynamic and ice cover model (MyLake) has been modified to take into account the effect of dynamic outflows in reservoirs and applied to two small but relatively deep regulated lakes (reservoirs) in Norway (Follsjøen and Tesse). The objective was to assess climate change impacts on the seasonal thermal characteristics, the withdrawal temperatures, and the reservoir ice cover dynamics with current operational regimes. The model solves the vertical energy balance on a daily time-step driven by meteorological and hydrological forcings: 2m air temperature, precipitation, 2m relative humidity, 10m wind speed, cloud cover, air pressure, solar insolation, inflow volume, inflow temperature and reservoir outflows. Model calibration with multi-seasonal data of temperature profiles showed that the model performed well in simulating the vertical water temperature profiles for the two study reservoirs. The withdrawal temperatures were also simulated reasonably well. The comparison between observed and simulated lake ice phenology (which were available only for one of the reservoirs - Tesse) was also reasonable taking into account the uncertainty in the observational data. After model testing and calibration, the model was then used to simulate expected changes in the future (2080s) due to climate change by considering

  12. Man-made lakes, ecological studies and conservation needs in Nigeria

    Directory of Open Access Journals (Sweden)

    P.A. Araoye

    2002-12-01

    Full Text Available The benefit derived from the creation of man-made lakes in Nigeria and other developing countries is usually associated with great risks. Whenever we establish a dam, it appears we dam the inherent consequences to the detriment of man and bis environment. Debts were incurred by the countries concerned, man and animals were displaced, arable lands destroyed including degradation of forest and wild life resources. The creation of dams have also ignored the prevention of man and bis life stock from the inherent spread of water borne diseases. The purpose for which a dam is created is threatened if man is indiscriminately exposed to the risk of water borne diseases. The poor and uneconomic management of the fish resources is also another major issue of concern. In order to tap the full potentials of reservoir projects and to promote conservation, it is important to have a round table talk involving all stake holders during the planning stage of such projects. Therefore apart from the engineering works, there is also need for collaboration with all experts from relates fields especially the biologists, sociologists and economists for bio-socio-economic reasons during the planning and implementation stages of dam projects in Nigeria and other developing countries.La creación de represas y lagos artificiales en Nigeria y en otros países en vías de desarrollo, produce importantes beneficios, pero trae también grandes riesgos, pues es difícil evitar sus consecuencias inherentes, hacia el detrimento del hombre y su ambiente. Los países que desarrollan este tipo de proyectos deben adquirir deudas, desplazar personas y animales y enfrentar la destrucción de tierras que podrían utilizarse para cultivo, así como también la degradación del bosque y la vida silvestre. Se ha ignorado además, el riesgo que representa para el hombre y su ganado, la exposición indiscriminada a enfermedades transmitidas por el agua. El manejo pobre y antieconómico de

  13. Studies of dry deposition of trace elements and diesel soot onto Lake Michigan and the Chesapeake Bay

    International Nuclear Information System (INIS)

    Ondov, J.M.; Caffrey, P.F.; Suarez, A.E.; Han, M.; Borgoul, P.V.

    1995-01-01

    As part of the Atmospheric Exchange Over Lakes and Oceans Study (AEOLOS) study, the University of Maryland participated in four intensive field campaigns, three on Lake Michigan (LM) and one on the Chesapeake Bay (CB), to determine the size distributions of potentially toxic elemental aerosol constituents, determine their sources, and their dry deposition loadings to surface waters. The work further seeks to elucidate the relative importance of constituents of fine- and coarse particles, as differentiation of these modes is essential to the eventual formation of control strategies. Unique components of the UMCP studies include (1) resolution of toxic elemental components of aerosol particles depositing to LM and CB by particle size and by source and (2) a Lake-wide evaluation of the importance of fine and coarse particle deposition to inorganic contamination of LM surface waters. In addition, a unique component of the Baltimore Study was the application of a sensitive iridium tracer to intentionally tag emissions form the City of Baltimore's sanitation truck fleet to tag the Baltimore urban plume and to determine the atmospheric behavior of diesel soot particles, a major source of urban carbon aerosol and the principle carrier of toxic polynuclear aromatic hydrocarbons. The work encompasses results for >40 elements by X-ray fluorescence and instrumental neutron activation analyses of more than 700 individual size-segregated aerosol, deposition, urban dust, and surface-water-suspended particulate samples. An overview of the results of these studies will be presented

  14. Radioecological studies of tritium movement in a tropical rain forest

    International Nuclear Information System (INIS)

    Martin, J.R.; Jordan, C.F.; Koranda, J.J.; Kline, J.R.

    1970-01-01

    Several experiments on the movement of tritium in a tropical ecosystem have been conducted in the montane rainforest of Eastern Puerto Rico by the Bio-Medical Division of the Lawrence Radiation Laboratory, Livermore, in cooperation with the Puerto Rico Nuclear Center. Tritiated whaler was used as a tracer for water movement in: a) mature evergreen trees of the climax rainforest; b) soil and substory vegetation and c) rapidly growling successional species. A feasibility study on the Atlantic Pacific Interoceanic Canal is currently being conducted. If thermonuclear explosives were used in constructing the canal, tritium would be deposited as tritiated water and distributed among the several biological compartments of the tropical ecosystem in that area. The main hydrogen compartments are water in the soil and in leaves, limbs and wood of forest trees. Organic tissue hydrogen comprises another compartment. In the tree experiment, tritiated water was injected directly into several species of mature, broad leaved evergreen tropical trees. Transpiration and residence time for tritium was determined from analyses of leaves sampled during a several month period. Transpiration ranged from 4 ml/day/gm dry leaf for an understory Dacryodes excelsa to 10.0 and 13.8 ml/day/gm dry leaf for a mature Sloanea berteriana and D. excelsa, respectively. Mean residence time for the S. berteriana was 3.9 ± 0.2 days and the understory and mature D. excelsa values were 9.5 ± 0.4 and 11.0 ± 0. 6 days, respectively. In another experiment, tritiated water was sprinkled over a 3.68 m 2 plot and its movement down into the soil and up into the vegetation growing on the plot was traced. The pattern of water movement in the soil was clearly demonstrated. The mean residence time for tritium in the soil and in trees was found to be 42 ± 2 days and 67 ± 9 days, respectively. The residence time for tritium in the trees in this experiment was considerably longer than for the single injected input

  15. Examining fire-induced forest changes using novel remote sensing technique: a case study in a mixed pine-oak forest

    Science.gov (United States)

    Meng, R.; Wu, J.; Zhao, F. R.; Cook, B.; Hanavan, R. P.; Serbin, S.

    2017-12-01

    Fire-induced forest changes has long been a central focus for forest ecology and global carbon cycling studies, and is becoming a pressing issue for global change biologists particularly with the projected increases in the frequency and intensity of fire with a warmer and drier climate. Compared with time-consuming and labor intensive field-based approaches, remote sensing offers a promising way to efficiently assess fire effects and monitor post-fire forest responses across a range of spatial and temporal scales. However, traditional remote sensing studies relying on simple optical spectral indices or coarse resolution imagery still face a number of technical challenges, including confusion or contamination of the signal by understory dynamics and mixed pixels with moderate to coarse resolution data (>= 30 m). As such, traditional remote sensing may not meet the increasing demand for more ecologically-meaningful monitoring and quantitation of fire-induced forest changes. Here we examined the use of novel remote sensing technique (i.e. airborne imaging spectroscopy and LiDAR measurement, very high spatial resolution (VHR) space-borne multi-spectral measurement, and high temporal-spatial resolution UAS-based (Unmanned Aerial System) imagery), in combination with field and phenocam measurements to map forest burn severity across spatial scales, quantify crown-scale post-fire forest recovery rate, and track fire-induced phenology changes in the burned areas. We focused on a mixed pine-oak forest undergoing multiple fire disturbances for the past several years in Long Island, NY as a case study. We demonstrate that (1) forest burn severity mapping from VHR remote sensing measurement can capture crown-scale heterogeneous fire patterns over large-scale; (2) the combination of VHR optical and structural measurements provides an efficient means to remotely sense species-level post-fire forest responses; (3) the UAS-based remote sensing enables monitoring of fire

  16. Reconnaissance study of uranium and fluorine contents of stream and lake waters, West Greenland

    International Nuclear Information System (INIS)

    Steenfelt, A.; Dam, E.

    1982-01-01

    The present study forms part of a current investigation on the applicability of geochemical methods in mineral exploration in Greenland. The sampling programme of 1981 comprised three parts: (1) A helicopter supported, low density, regional sampling (1 sample/30 km 2 ) of stream water and stream sediment in the area covered by map sheet 66 V.2, south-east of Soendre Stroemfjord. A total of 207 water samples was obtained. (2) Detailed sampling within a 20 km 2 area of lake and stream water (71 samples) from a camp at 66deg49'N, 25deg37'W, 25 km south-west of Soendre Stroemfjord. (3) Reconnaissance sampling, by boat, along the southern part of the west coast of Greenland. The aim of this reconnaissance was to obtain information on the character of the drainage systems and on the availability of sample media (water, stream sediment, aquatic moss) for geochemical exploration. A total of 195 water samples were collected. In addition, rust zones and areas of known mineralisation along the coast were sampled. (author)

  17. Using a Computational Study of Hydrodynamics in the Wax Lake Delta to Examine Data Sharing Principles

    Directory of Open Access Journals (Sweden)

    Qian Zhang

    2017-01-01

    Full Text Available In this paper we describe a complex dataset used to study the circulation and wind-driven flows in the Wax Lake Delta, Louisiana, USA under winter storm conditions. The whole package bundles a large dataset (approximately 74 GB, which includes the numerical model, software and scripts for data analysis and visualization, as well as detailed documentation. The raw data came from multiple external sources, including government agencies, community repositories, and deployed field instruments and surveys. Each raw dataset goes through the processes of data QA/QC, data analysis, visualization, and interpretation. After integrating multiple datasets, new data products are obtained which are then used with the numerical model. The numerical model undergoes model verification, testing, calibration, and optimization. With a complex algorithm of computation, the model generates a structured output dataset, which is, after post-data analysis, presented as informative scientific figures and tables that allow interpretations and conclusions contributing to the science of coastal physical oceanography. Performing this study required a tremendous amount of effort. While the work resulted in traditional dissemination via a thesis, journal articles and conference proceedings, more can be gained. The data can be reused to study reproducibility or as preliminary investigation to explore a new topic. With thorough documentation and well-organized data, both the input and output dataset should be ready for sharing in a domain or institutional repository. Furthermore, the data organization and documentation also serves as a guideline for future research data management and the development of workflow protocols. Here we will describe the dataset created by this study, how sharing the dataset publicly could enable validation of the current study and extension by new studies, and the challenges that arise prior to sharing the dataset.

  18. Managing Forests for Water Quality: Streamside Management Zones

    OpenAIRE

    Daniels, Barbara

    2012-01-01

    Throughout Utah, forestlands act as collectors of pure water. Much of Utah’s water supply originates in high elevation forested watersheds. These forests play a vital role in purifying and maintaining clean water for streams, lakes and groundwater.

  19. Climatic and pollution influences on ecosystem processes in northern hardwood forests

    Science.gov (United States)

    Kurt S. Pregitzer; David D. Reed; Glenn D. Mroz; Andrew J. Burton; John A. Witter; Donald A. Zak

    1996-01-01

    The Michigan gradient study was established in 1987 to examine the effects of climate and atmospheric deposition on forest productivity and ecosystem processes in the Great Lakes region. Four intensively-monitored northern hardwood study sites are located along a climatic and pollutant gradient extending from southern lower Michigan to northwestern upper Michigan. The...

  20. Establishment patterns of water-elm at Catahoula Lake, Louisiana

    Science.gov (United States)

    Karen S. Doerr; Sanjeev Joshi; Richard F. Keim

    2015-01-01

    At Catahoula Lake in central Louisiana, an internationally important lake for water fowl, hydrologic alterations to the surrounding rivers and the lake itself have led to an expansion of water-elm (Planera aquatic J.F. Gmel.) into the lake bed. In this study, we used dendrochronology and aerial photography to quantify the expansion of water-elm in the lake and identify...

  1. Building America Case Study: Zero Energy Ready Home Multifamily Project: Mutual Housing at Spring Lake, Woodland, California

    Energy Technology Data Exchange (ETDEWEB)

    2015-09-01

    Building cost effective, high performance homes that provide superior comfort, health, and durability is the goal of the Department of Energy's (DOE's) Zero Energy Ready Homes (ZERH) program. Through Building America research and other innovative programs throughout the country, many of the technical challenges to building to the ZERH standard have been addressed. This case study describes the development of a 62-unit multifamily community constructed by nonprofit developer Mutual Housing at the Spring Lake subdivision in Woodland, CA. The Spring Lake project is expected to be the first ZERH-certified multifamily project nationwide. Building America team Alliance for Residential Building Innovation worked with Mutual Housing throughout the project. The case study discusses challenges encountered, lessons learned, and how obstacles were overcome. An objective of this project was to gain a highly visible foothold for residential buildings built to the DOE ZERH specification that can be used to encourage participation by other California builders.

  2. The preglacial sediment record of Lake Ladoga, NW Russia - first results from a multi-proxy study on a 23 m sediment record

    Science.gov (United States)

    Gromig, R.; Melles, M.; Wagner, B.; Krastel, S.; Andreev, A.; Fedorov, G.; Just, J.; Wennrich, V.; Savelieva, L.; Subetto, D.; Shumilovskikh, L.

    2016-12-01

    The joint German-Russian project 'PLOT - Paleolimnological Transect' aims to recover lake sediment sequences along a more than 6000 km long longitudinal transect across the Eurasian Arctic in order to study the Late Quaternary climatic and environmental history. The eastern end of the PLOT transect is formed by the well-studied record from Lake El'gygytgyn (NE Siberia). Lake Ladoga (N 60°50' E 31°30') is Europe's largest lake, both by size and volume and forms the westernmost end of the transect. Whereas modern sedimentation as well as the Holocene and Late Glacial history of Lake Ladoga have intensely been studied, the preglacial history of the lake is poorly studied to date by sediment cores drilled in the 1930's. A seismic survey of Lake Ladoga in summer 2013 revealed unconformities in the western lake basin, which may separate preglacial sediments in isolated depressions from Late Glacial and Holocene sediment successions above. A 23 m long sediment core (Co1309) was retrieved from one of these depressions. Core Co1309 was investigated by XRF-scanning, magnetic susceptibility measurements, as well as pollen, grain-size, and bio-geochemical analyses. An age-depth model combining radiocarbon, OSL, and paleomagnetic dates is in progress. Both, the pollen results and the OSL ages from the base of the record indicate a deposition during MIS 5e (Eemian). The well sorted reddish sands from this interval contain dinoflagellates suggesting at least brackish conditions, likely due to the existence of a gateway connecting a precursor of the Baltic Sea with the White Sea via Lake Ladoga. The Late Glacial sequence consists of greyish varved clays of decreasing thickness upwards with sporadically intercalated sand layers. The Holocene sequence is composed of brownish diatomaceous silty clay with minor proportions of sand.

  3. A Case Study on the Selection of Purification Project of Lake

    Directory of Open Access Journals (Sweden)

    Shen Shilong

    2015-01-01

    Full Text Available This paper will mainly talk about best scheme for the water purification project of the Lake. The engineering used the water diversion metabolism method to purify the water. If the lake area and the water volume are small, the metabolic cycle is relatively short; if the lake area and the water volume are large, the metabolic cycle is relatively long. Simultaneously, the larger the water flow is, the shorter the metabolic cycle period is and the higher the average metabolic rate is. The process of the water metabolism is in agreement with the direction of the water flow movement. With the gradual metabolism of water, different water bodies begin to dilute and diffuse. The engineers will choose the most appropriate water division project according to different water division volumes and water division routes.

  4. Analyzing the impacts of forest disturbance and regrowth on watershed hydrology: A case study from the Homochitto Watershed, Mississippi

    Science.gov (United States)

    Yeo, I.; Islam, A.; Huang, C.

    2009-12-01

    Forests are efficient sinks and reservoirs of terrestrial carbons. They can relieve or amplify the adverse impacts of global warming and climate variability and hence, managing forests has been the most important sustainable strategy to mitigate climatic impacts. However, forest management often involves a large scale landscape transformation of land use and cover, and brings significant changes on water resources to the local community. This study is to evaluate the impacts of forest management and disturbance on water quality and quanity in the Homochitto watershed (Mississippi), where forest management and disturbance have occurred on a large scale over long time scales. Using a watershed simulation model (Soil and Water Assessment Tool) and a long term water monitoring data from USGS and US EPA, we will investigate how the spatial heterogeneity of land use, vegetation cover, topography, and climate affect water cycles (e.g., soil water content, water yields), and water quality (e.g., nutrients and sediments) at multiple spatial and temporal scales. Historic chronologies of forest disturbance maps will be generated with a number of satellite-based measurements (such as Landsat, MODIS, and aerial photographs), Geospatial datasets (including MS Gap Analysis Project (GAP), National Land Cover Database (NLCD)), field measurements from the US Forest Service Forest Inventory Analysis (FIA) database, and historic records on forest land management in the region, characterizing the human induced changes in the forest landscape. This study will provide valuable information to better understand the hydrologic feedbacks to changing forests and climate system.

  5. Comparative study of cadmium and lead accumulations in Cambarus bartoni (Fab. ) (Decapoda, Crustacea) from an acidic and a neutral lake

    Energy Technology Data Exchange (ETDEWEB)

    Keenan, S.; Alikhan, M.A. (Laurentian Univ., Sudbury, Ontario (Canada))

    1991-07-01

    The purpose of the study reported in this paper was to compare concentrations of lead and cadmium in the sediment and water, as well as in the crayfish, Cambarus Bartoni (Fab.) (Decapoda - Crustacea) trapped from an acidic and a neutral lake in the Sudbury district of Northeastern Ontario. Hepatopancreatic, alimentary canal, tail muscles and exoskeletal concentrations in the crayfish are also examined to determine specific tissue sites for these accumulations.

  6. Quantifying Streamflow Variations in Ungauged Lake Basins by Integrating Remote Sensing and Water Balance Modelling: A Case Study of the Erdos Larus relictus National Nature Reserve, China

    Directory of Open Access Journals (Sweden)

    Kang Liang

    2017-06-01

    Full Text Available Hydrological predictions in ungauged lakes are one of the most important issues in hydrological sciences. The habitat of the Relict Gull (Larus relictus in the Erdos Larus relictus National Nature Reserve (ELRNNR has been seriously endangered by lake shrinkage, yet the hydrological processes in the catchment are poorly understood due to the lack of in-situ observations. Therefore, it is necessary to assess the variation in lake streamflow and its drivers. In this study, we employed the remote sensing technique and empirical equation to quantify the time series of lake water budgets, and integrated a water balance model and climate elasticity method to further examine ELRNNR basin streamflow variations from1974 to 2013. The results show that lake variations went through three phases with significant differences: The rapidly expanding sub-period (1974–1979, the relatively stable sub-period (1980–1999, and the dramatically shrinking sub-period (2000–2013. Both climate variation (expressed by precipitation and evapotranspiration and human activities were quantified as drivers of streamflow variation, and the driving forces in the three phases had different contributions. As human activities gradually intensified, the contributions of human disturbances on streamflow variation obviously increased, accounting for 22.3% during 1980–1999 and up to 59.2% during 2000–2013. Intensified human interferences and climate warming have jointly led to the lake shrinkage since 1999. This study provides a useful reference to quantify lake streamflow and its drivers in ungauged basins.

  7. Arcellacea (testate amoebae) as bio-indicators of road salt contamination in lakes.

    Science.gov (United States)

    Roe, Helen M; Patterson, R Timothy

    2014-08-01

    Winter deicing operations occur extensively in mid- to high-latitude metropolitan regions around the world and result in a significant reduction in road accidents. Deicing salts can, however, pose a major threat to water quality and aquatic organisms. In this paper, we examine the utility of Arcellacea (testate amoebae) for monitoring lakes that have become contaminated by winter deicing salts, particularly sodium chloride. We analysed 50 sediment samples and salt-related water property variables (chloride concentrations; conductivity) from 15 lakes in the Greater Toronto Area and adjacent areas of southern Ontario, Canada. The sampled lakes included lakes in proximity to major highways and suburban roads and control lakes in forested settings away from road influences. Samples from the most contaminated lakes, with chloride concentrations in excess of 400 mg/l and conductivities of >800 μS/cm, were dominated by species typically found in brackish and/or inhospitable lake environments and by lower faunal diversities (lowest Shannon diversity index values) than samples with lower readings. Q-R-mode cluster analysis and detrended correspondence analysis (DCA) resulted in the recognition of four assemblage groupings. These reflect varying levels of salt contamination in the study lakes, along with other local influences, including nutrient loading. The response to nutrients can, however, be isolated if the planktic eutrophic indicator species Cucurbitella tricuspis is removed from the counts. The findings show that the group has considerable potential for biomonitoring in salt-contaminated lakes, and their presence in lake sediment cores may provide significant insights into long-term benthic community health, which is integral for remedial efforts.

  8. Lake biota response to human impact and local climate during the last 200 years: A multi-proxy study of a subalpine lake (Tatra Mountains, W Carpathians).

    Science.gov (United States)

    Hamerlík, Ladislav; Dobríková, Daniela; Szarlowicz, Katarzyna; Reczynski, Witold; Kubica, Barbara; Šporka, Ferdinand; Bitušík, Peter

    2016-03-01

    Element content, loss-on-ignition, chironomid analysis and (210)Pb dating were applied on a sediment core from a subalpine Tatra lake (Popradské pleso) to reveal the response of aquatic biota to eutrophication induced by human activities in the lake catchment. The lead dating indicates that the 0-8 cm section of the core represents the past ca 200 years, ending at ~1814 AD. Comparing the key changes of the proxies with human activities that are historically well documented, four phases of the recent lake development were distinguished: (1) a pre-tourism phase, (2) a phase of increasing touristic activity and early cottage development, (3) a phase of eutrophication, and (4) a phase of post-eutrophication. Neither touristic activity, nor early cottage development around the lake (1st and 2nd phases) had considerable influence on the chironomid assemblage structure or organic content of the lake. The most significant change both in chironomid assemblage structure and loss-on-ignition occurred during the 3rd phase, when a big tourist hotel was built close by the lake and started contaminating it via direct wastewater input. However, the structure of the chironomid assemblage has not changed significantly over time and the dominating taxa remained the same during the whole period. Parallel with the nutrient signal of the paleo assemblage, a secondary signal has been identified as the ratio of rheophilic taxa on total abundance that did not correlate with the sediment's organic content, and is most likely driven by local climatic oscillations. Changes of most of metal elements concentrations reflected rather bigger scale changes of industrial activities than local scale human disturbances. Our results indicate that hydromorphological properties can moderate the impact of organic pollution on the lake biota. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Studies on the causes of forest decline in Nanshan, Chongqing.

    Science.gov (United States)

    Shu-Wen, Y; Yong-Mei, B; Guang-Jing, M; Jia-Ju, L

    1990-05-01

    Nanshan is located in the south suburb of Chongqing, Sichuan province in China. It is about 10 km from the city of Chongqing. There are about 2000 ha of forest, mainly Masson pines (Pinus massoniana Lamb) which have exhibited decline since the beginning of the 1980s. Surveys of stands estimated that 85% of Masson pines are injured. Symptomology of Masson pines includes tip necrosis of needles, thin crown, reduced needle length, premature abscission, branch dieback, reduced radial growth. The foliage of broadleaf treesRobinia pseudoacacia L,Quercus dentata Thunb,Eucalyptus robusta Sm,Erythrina variegata var. orientalis (L) Merr,Faulownia fortunei (Seem) Hemsl,Rosa chinensis Jacq, also displayed necrotic lesions, both marginal and interveinous, most are brown or bleached. Foliage symptoms are similar to that produced in laboratory fumigation experiments with gaseous air pollutants SO2 or HF. The foliage injury intensity is related to the distance from the city. Forest in some localities furthest from the city exhibit approximately normal growth.Three monitoring sites had been selected in Nanshan forest area. At two sites pine trees were severely damaged. At another site they showed little damage. Atmospheric SO2 and fluoride concentrations had been examined. The average value of SO2 and fluoride concentrations at the two former sites were much higher than that at the latter site. The injury intensity was consistent with an increase in the concentrations of SO2 and fluoride. The sulphur and fluoride contents of tree leaves were also monitored. Sulphur contents of pine needles at the two former sites were generally more than that at the latter. The same tendency is observed in broadleaf trees. Higher levels of fluoride had been found in foliage of injured trees compared to unijured trees.Chongqing is also an acid rain region. The yearly average pH value of precipitation approaches to 4.0, and the frequency 100%. The pH values of acid rain at the three sites in Nanshan

  10. Nonindustrial private forest owners' opinions to and awareness of energy wood market and forest-based bioenergy certification. Results of a case study from Finnish Karelia

    Energy Technology Data Exchange (ETDEWEB)

    Halder, Pradipta; Mei, Qu; Pelkonen, Paavo [Eastern Finland Univ., Joensuu (Finland). School of Forest Sciences; Weckroth, Timo

    2012-12-01

    Nonindustrial private forest owners (NIPFs) in Finland are important stakeholders of forest management and roundwood supply decisions. Their role will also be significant to supply energy wood to meet Finland's target for renewable energy in the future. The main objectives of this study were to explore the opinions and awareness of the Finnish NIPFs related to the energy wood market and forest-based bioenergy certification issues in Finland and their relevance for future bioenergy policies. A questionnaire-based survey was conducted among NIPFs in Finnish Karelia (N = 79). NIPFs considered price as the main deciding factor in harvesting and selling of energy wood. The present low price of energy wood compared to pulpwood did not motivate them to increase harvesting and selling of energy wood. The NIPFs appeared to be unaware of the forest-based bioenergy certification. However, they expected that such certification schemes would be easy to follow, develop energy wood market, and promote environmentally sound forest management practices in Finland. Private forest owners' associations and personal information letters emerged as the most favored means to disseminate information on forest-based bioenergy certification to the Finnish NIPFs. The study explored the opinions and awareness of the Finnish NIPFs related to energy wood market and forest based bioenergy certification from Finnish Karelia. The conclusions derived from the study might be highly policy-relevant concerning the development of energy wood market and related certification schemes. Future studies should include larger sample size for increasing the representativeness of the findings. (orig.)

  11. Focused groundwater discharge of phosphorus to a eutrophic seepage lake (Lake Væng, Denmark)

    DEFF Research Database (Denmark)

    Kidmose, Jacob Baarstrøm; Nilsson, Bertel; Engesgaard, Peter Knudegaard

    2013-01-01

    A study on Lake Væng in Denmark demonstrates a high potential for loading of phosphorous via groundwater to seepage lakes. Groundwater discharges are displayed as an important source of phosphorous to a lake due to: (1) high concentrations in the aquifer just below the lake, and (2) the main flow...

  12. Morphometric Studies on Anodonta Anatine Bivalve Population from the Dognecea Lake

    Directory of Open Access Journals (Sweden)

    Marian Bura

    2011-10-01

    Full Text Available In the Dognecea Lake, near town Bocsa in Caras-Severin county a strong bivalve population has been discovered from the duck mussel specie (Anodonta anatina. Harvested individuals were transported to the Aquaculture laboratory where measurements and correct identification was made. This specie is considered endangered but in Banat area, especially in the Dognecea Lake it is well represented, having an ecological importance, but the bivalve can have an economical importance too, due to the high percentage of edible part of 56.5%.

  13. Consequences of eutrophication in the management of water resources in Mediterranean reservoirs: A case study of Lake Cedrino (Sardinia, Italy

    Directory of Open Access Journals (Sweden)

    Bachisio Mario Padedda

    2017-10-01

    Full Text Available One of the primary detrimental effects of eutrophication is the tendency of nuisance cyanobacterial species to increase in number and biomass in freshwater ecosystems. The aim of this study was to investigate possible management actions to control eutrophication and assure water use of a eutrophic deep Mediterranean climate reservoir, dominated by cyanobacteria. With this goal, we defined the trophic state of Lake Cedrino (Sardinia, Italy and studied its phytoplankton, paying particular attention to cyanobacteria, and to seasonal variation of phytoplankton in relation to seasonal variation of environmental variables. The water samples were collected monthly from September 2010 to August 2011 at differing depths from the surface of the water to the bottom at a station located in the deeper portion of the reservoir. Physical, chemical, nutrient, qualitative and quantitative analyses of phytoplankton were performed, and the trophic state was evaluated based on the Trophic State Index and the OECD model. Abundance of nutrients and phytoplankton (cell density, biomass and chlorophyll a indicated a eutrophic condition of the reservoir. In summer, phytoplankton species composition was dominated by nuisance cyanobacteria, particularly Aphanizomenon flosaquae, thereby requiring management plans for harmful blooms. On the base of lake features, we propose management actions at different scales and levels to resolve eutrophication and to allow water use: from nutrient load reduction in the watershed (primarily from point-sources to deep water aeration, to immediately face an attenuation of eutrophic effects. This study is the first explorative step in planning restoration of Lake Cedrino.

  14. Role of neutron activation analysis in the study of heavy metal pollution of a lake-river system

    International Nuclear Information System (INIS)

    Filby, R.H.; Shah, K.R.; Funk, W.H.

    1974-01-01

    Details of a study of combined organic and metallic pollution of the Coeur d'Alene Lake-River and Spokane River system and the role played by nuclear techniques in the investigation are presented. The Coeur d'Alene River drains through the N. Idaho Pb--Zn mining region of Kellogg and the mining industry is the major source of metallic pollution of the lake and river system. The first part of the study has involved the determination of Pb, Zn, Ag, Cd, As, Cu, Sb, Co, Cr, Cs, Rb, Sc, Ba, Eu, La, Tb, Y, Zr, Fe, Mn, Mo, by INAA in waters, sediments and organisms throughout the region. Extremely high values for Pb, Zn, Sb, Fe and other metals were found in the Coeur d'Alene River delta sediments and in the lake sediments. Results from the study of metals in an aquatic ecosystem show the value of combining nuclear techniques with other methods of trace analysis in practical pollution problems

  15. A Study of the Epiphytic Orchids in Jobolarangan Forest

    Directory of Open Access Journals (Sweden)

    ADIANI VIVIATI

    2001-07-01

    Full Text Available The objective of the research was to know the species of epiphytic orchids in Jobolarangan forest. The orchid samples were taken from all stand-plants. The plants were chosen randomly by considering the diversity and richness of orchids that attach on it. Each plant was sampled in three repetitions. Sampling of orchids existence in the plant’s stand were done using transect method through a zonation system. In this research 11 epiphytic-orchids such as Bulbophyllum bakhuizenii Stenn, Coelogyne miniata Lindl, Coelogyne rochussenii de Vr., Dendrobium bigibbum Lindl., Dendrobchilum longifolium, Eria bogoriensis, J.J.S. Liparis caespitosa (Thou. Lindl., Liparis pallida (Bl.. Pholidota globosa (Bl. Lindl., Polystachya flavescens (Bl. J.J.S., and Trichoglottis sp. were found. The host plant stand that was attached with most orchids was Schefflera fastigiata and Saurauia bracteosa, generally in zone three.

  16. New Whole-House Solutions Case Study: Zero Energy Ready Home Multifamily Project: Mutual Housing at Spring Lake

    Energy Technology Data Exchange (ETDEWEB)

    D. Springer and A. German

    2015-09-01

    Building cost effective, high performance homes that provide superior comfort, health, and durability is the goal of the Department of Energy's (DOE's) Zero Energy Ready Homes (ZERH) program. This case study describes the development of a 62-unit multifamily community constructed by nonprofit developer Mutual Housing at the Spring Lake subdivision in Woodland, California. The Spring Lake project is expected to be the first ZERH-certified multifamily project nationwide. Building America team Alliance for Residential Building Innovation worked with Mutual Housing throughout the project. An objective of this project was to gain a highly visible foothold for residential buildings built to the DOE ZERH specification that can be used to encourage participation by other California builders.

  17. Fish as bioindicators in aquatic environmental pollution assessment: A case study in Lake Victoria wetlands, Uganda

    Science.gov (United States)

    Naigaga, I.; Kaiser, H.; Muller, W. J.; Ojok, L.; Mbabazi, D.; Magezi, G.; Muhumuza, E.

    Growing human population and industrialization have led to the pollution of most aquatic ecosystems and consequent deterioration in environmental water quality. Indicator organisms are needed to improve assessment programmes on the ecological impacts of anthropogenic activities on the aquatic environment. Fish have been widely documented as useful indicators of environmental water quality because of their differential sensitivity to pollution. This study investigated the environmental water quality of selected wetland ecosystems using fish as biological indicators. Fish community structure in relation to water quality was assessed in five wetlands along the shoreline of Lake Victoria from August 2006 to June 2008. Four urban wetlands were variedly impacted by anthropogenic activities while one rural wetland was less impacted, and served as a reference site. Fish species diversity, abundance and richness were assessed, and canonical correspondence analysis (CCA) was used to evaluate the relationship between the fish communities and environmental variables. Results revealed that urban effluent impacted negatively on water quality and consequently the fish community structure. A total of 29 fish species were recorded throughout the study with the lowest number of 15 species recorded in the most impacted site. Shannon diversity and Margalef species richness indices were highest at the references site and lowest at the most impacted site. Wetland haplochromis species dominated the reference site, while oreochromis species dominated the most impacted site. The inshore locations registered higher species diversity and low species richness than the offshore locations. Low dissolved oxygen, pH, secchi depth and high electrical conductivity, total phosphorous, and total nitrogen were strongly associated with the effluent-impacted sites and greatly influenced the fish community structure. This study recommends the use of fish as valuable biological indicators in aquatic

  18. Unregulated aquaculture and invasive alien species: a case study of the African Catfish Clarias gariepinus in Vembanad Lake (Ramsar Wetland, Kerala, India

    Directory of Open Access Journals (Sweden)

    K. Krishnakumar

    2011-05-01

    Full Text Available Indiscriminate and illegal farming of the African Catfish Clarias gariepinus, in central Kerala has now resulted in the escape and spread of the species into Vembanad Lake, a large brackish water wetland and inland fish diversity hotspot. We collected 17 individuals of C. gariepinus ranging in size from 200 to 750 mm from different locations in the southern sector of the lake during a field survey conducted in 2007. Samples comprised of mature specimens of both sexes indicating their reproductive potential in the study area. The possible impacts of spread of C. gariepinus into natural water bodies of Kerala, especially the Vembanad Lake, and options for their management are discussed.

  19. Evolution of soil and vegetation cover on the bottom of drained thermokarst lake (a case study in the European Northeast of Russia)

    Science.gov (United States)

    Kaverin, Dmitry; Pastukhov, Alexander

    2015-04-01

    The evolution of soils and landscapes has been studied in a lake bed of former thermokarst lake, which was totally drained in 1979. Melioration of thermokarst lakes was conducted experimentally and locally under Soviet economics program during 1970-s. The aim of the program was to increase in biomass productivity of virgin tundra permafrost-thermokarst sites under agricultural activities. The former thermokarst lake "Opytnoe" located in the Bolshezemelskaya Tundra, Russian European Northeast. The lake bed is covered by peat-mineral sediments, which serves as soil-forming sediments favoring subsequent permafrost aggradation and cryogenic processes as well. Initially, after drainage, swampy meadows had been developed almost all over the lake bed. Further on, succession of landscape went diversely, typical and uncommon tundra landscapes formed. When activated, cryogenic processes favored the formation of peat mounds under dwarf shrub - lichen vegetation (7% of the area). Frost cracks and peat circles affected flat mounds all over the former lake bottom. On drained peat sites, with no active cryogenic processes, specific grass meadows on Cryic Sapric Histosols were developed. Totally, permafrost-affected soils occupy 77% of the area (2011). In some part of the lake bed further development of waterlogging leads to the formation of marshy meadows and willow communities where Gleysols prevail. During last twenty years, permafrost degradation has occurred under tall shrub communities, and it will progress in future. Water erosion processes in the drained lake bottom promoted the formation of local hydrographic network. In the stream floodplain grassy willow-stands formed on Fluvisols (3% of the area). The study has been conducted under Clima-East & RFBR 14-05-31111 projects.

  20. A study of the river basins and limnology of five humic lakes on Chiloé Island Estudio de la cuenca y limnología en cinco lagos húmicos de la Isla Chiloé

    Directory of Open Access Journals (Sweden)

    L. VILLALOBOS

    2003-12-01

    Full Text Available From November 1996 to October 1997, the river basins of five humic lakes on Chiloé Island were studied monthly: Lakes Natri, Tepuhueico, Tarahuín, Huillinco and Cucao. The objective of this study was to know the catchment area, river basin and the main physical, chemical and biological characteristics of these humic lakes. The trophic status, the actual loading, and the mass balances of phosphorus and nitrogen were determined in relation to anthropogenic activities. Lakes Cucao and Huillinco were characterized by a marine influence. All the lakes had brown coloured waters, caused by humic substances, which limit their transparency. Lake Natri was the deepest (58 m, whereas Lake Tepuhueico had the shallowest depth (25 m. Total phosphorus and nitrogen fluctuated between 23.5 and 35 µg L-1 and 197 and 380 mug L-1 (annual average in lakes Natri, Tepuhueico and Tarahuín, respectively. Lakes Cucao and Huillinco showed extremely high concentrations of total nitrogen (annual average or = 3,000 mug L-1 and total phosphorus (= 223 and 497 mug L-1, and were classified as hyper-eutrophic. Lake Tarahuín registered the greatest diversity of phytoplankton, with 55 species, including Ceratium hirundinella which also occurred in lakes Cucao and Tarahuín. The diversity of the zooplankton community varied across these lakes. The presence of Diaptomus diabolicus (Tumeodiaptomus d. Dussart 1979 (Cucao, Huillinco and Tepuhueico is noteworthy since this extends its geographical distribution to the south

  1. Sustainable forest management of Natura 2000 sites: a case study from a private forest in the Romanian Southern Carpathians

    Directory of Open Access Journals (Sweden)

    Helge Walentowski

    2013-07-01

    Full Text Available Biodiversity and forest management are analyzed for a 500 ha privately owned forest within the Natura 2000 area “ROSCI0122 Muntii Fagaras”. Habitat types and indicator species are identified to measure environmental quality. Working towards an integrated approach to conservation, a range of options that will result in sustainable forest management are then considered. For beech forests light heterogeneity emerges as a crucial management target to ensure tree species richness and structural diversity as a basis for saving indicator species such as Morimus funereus, Cucujus cinnaberinus, Bolitophagus reticulatus and Xestobium austriacum. For spruce forests thinning over a broad range of diameters and maintenance of veteran trees would provide habitats for indicator species such asOlisthaerus substriatus. The populations of a number of bird species would be increased by strip-harvesting slopes: species such as Tetrao urogallus, Bonasia bonasia and Ficedula parva prefer forest margins. Steep slopes, and the areas around springs and watercourses, as well as rock faces, should remain unmanaged. Future management should start with a grid-based inventory to create an objective database of forest structure and life. An example is presented for high-elevation spruce forest. The inventory should quantify the variations in diameter, height and volume of trees per unit area. Such data would allow the advanced planning of forest operations. We discuss a wide range of administrative and organizational changes; changes that are needed for the sustainable forest management of the vast close-to-natural forests of the Muntii Fagaras, the maintenance of the Nardusgrasslands and the protection of wetland vegetation around springs and streams in this Natura 2000-area. 

  2. Integration of carbon conservation into sustainable forest management using high resolution satellite imagery: A case study in Sabah, Malaysian Borneo

    Science.gov (United States)

    Langner, Andreas; Samejima, Hiromitsu; Ong, Robert C.; Titin, Jupiri; Kitayama, Kanehiro

    2012-08-01

    Conservation of tropical forests is of outstanding importance for mitigation of climate change effects and preserving biodiversity. In Borneo most of the forests are classified as permanent forest estates and are selectively logged using conventional logging techniques causing high damage to the forest ecosystems. Incorporation of sustainable forest management into climate change mitigation measures such as Reducing Emissions from Deforestation and Forest Degradation (REDD+) can help to avert further forest degradation by synergizing sustainable timber production with the conservation of biodiversity. In order to evaluate the efficiency of such initiatives, monitoring methods for forest degradation and above-ground biomass in tropical forests are urgently needed. In this study we developed an index using Landsat satellite data to describe the crown cover condition of lowland mixed dipterocarp forests. We showed that this index combined with field data can be used to estimate above-ground biomass using a regression model in two permanent forest estates in Sabah, Malaysian Borneo. Tangkulap represented a conventionally logged forest estate while Deramakot has been managed in accordance with sustainable forestry principles. The results revealed that conventional logging techniques used in Tangkulap during 1991 and 2000 decreased the above-ground biomass by an annual amount of average -6.0 t C/ha (-5.2 to -7.0 t C/ha, 95% confidential interval) whereas the biomass in Deramakot increased by 6.1 t C/ha per year (5.3-7.2 t C/ha, 95% confidential interval) between 2000 and 2007 while under sustainable forest management. This indicates that sustainable forest management with reduced-impact logging helps to protect above-ground biomass. In absolute terms, a conservative amount of 10.5 t C/ha per year, as documented using the methodology developed in this study, can be attributed to the different management systems, which will be of interest when implementing REDD+ that

  3. Shoreline change assessment using multi-temporal satellite images: a case study of Lake Sapanca, NW Turkey.

    Science.gov (United States)

    Duru, Umit

    2017-08-01

    The research summarized here determines historical shoreline changes along Lake Sapanca by using Remote Sensing (RS) and Geographical Information Systems (GIS). Six multi-temporal satellite images of Landsat Multispectral Scanner (L1-5 MMS), Enhanced Thematic Mapper Plus (L7 ETM+), and Operational Land Imager Sensors (L8 OLI), covering the period between 17 June 1975 and 15 July 2016, were used to monitor shoreline positions and estimate change rates along the coastal zone. After pre-possessing routines, the Normalized Difference Water Index (NDWI), Modified Normalized Difference Water Index (MNDWI), and supervised classification techniques were utilized to extract six different shorelines. Digital Shoreline Analysis System (DSAS), a toolbox that enables transect-based computations of shoreline displacement, was used to compute historical shoreline change rates. The average rate of shoreline change for the entire cost was 2.7 m/year of progradation with an uncertainty of 0.2 m/year. While the great part of the lake shoreline remained stable, the study concluded that the easterly and westerly coasts and deltaic coasts are more vulnerable to shoreline displacements over the last four decades. The study also reveals that anthropogenic activities, more specifically over extraction of freshwater from the lake, cyclic variation in rainfall, and deposition of sediment transported by the surrounding creeks dominantly control spatiotemporal shoreline changes in the region. Monitoring shoreline changes using multi-temporal satellite images is a significant component for the coastal decision-making and management.

  4. Studies on the Biodiversity of Halophilic Microorganisms Isolated from El-Djerid Salt Lake (Tunisia under Aerobic Conditions

    Directory of Open Access Journals (Sweden)

    Abdellatif Boudabous

    2009-01-01

    Full Text Available Bacterial and archaeal aerobic communities were recovered from sediments from the shallow El-Djerid salt lake in Tunisia, and their salinity gradient distribution was established. Six samples for physicochemical and microbiological analyses were obtained from 6 saline sites in the lake for physico-chemical and microbiological analyses. All samples studied were considered hypersaline with NaCl concentration ranging from 150 to 260 g/L. A specific halophilic microbial community was recovered from each site, and characterization of isolated microorganisms was performed via both phenotypic and phylogenetic approaches. Only one extreme halophilic organism, domain Archaea, was isolated from site 4 only, whereas organisms in the domain Bacteria were recovered from the five remaining sampling sites that contained up to 250 g/L NaCl. Members of the domain Bacteria belonged to genera Salicola, Pontibacillus, Halomonas, Marinococcus, and Halobacillus, whereas the only member of domain Archaea isolated belonged to the genus Halorubrum. The results of this study are discussed in terms of the ecological significance of these microorganisms in the breakdown of organic matter in Lake El-Djerid and their potential for industry applications.

  5. Effect of DOC on evaporation from small Wisconsin lakes

    Science.gov (United States)

    Watras, C. J.; Morrison, K. A.; Rubsam, J. L.

    2016-09-01

    Evaporation (E) dominates the loss of water from many small lakes, and the balance between precipitation and evaporation (P-E) often governs water levels. In this study, evaporation rates were estimated for three small Wisconsin lakes over several years using 30-min data from floating evaporation pans (E-pans). Measured E was then compared to the output of mass transfer models driven by local conditions over daily time scales. The three lakes were chosen to span a range of dissolved organic carbon (DOC) concentrations (3-20 mg L-1), a solute that imparts a dark, tea-stain color which absorbs solar energy and limits light penetration. Since the lakes were otherwise similar, we hypothesized that a DOC-mediated increase in surface water temperature would translate directly to higher rates of evaporation thereby informing climate response models. Our results confirmed a DOC effect on surface water temperature, but that effect did not translate to enhanced evaporation. Instead the opposite was observed: evaporation rates decreased as DOC increased. Ancillary data and prior studies suggest two explanatory mechanisms: (1) disproportionately greater radiant energy outflux from high DOC lakes, and (2) the combined effect of wind speed (W) and the vapor pressure gradient (es - ez), whose product [W(es - ez)] was lowest on the high DOC lake, despite very low wind speeds (<1.5 m s-1) and steep forested uplands surrounding all three lakes. Agreement between measured (E-pan) and modeled evaporation rates was reasonably good, based on linear regression results (r2: 0.6-0.7; slope: 0.5-0.7, for the best model). Rankings based on E were similar whether determined by measured or modeled criteria (high DOC < low DOC). Across the 3 lakes and 4 years, E averaged ∼3 mm d-1 (C.V. 9%), but statistically significant differences between lakes resulted in substantial differences in cumulative E that were consistent from year to year. Daily water budgets for these lakes show that inputs

  6. Initial soil respiration response to biomass harvesting and green-tree retention in aspen-dominated forests of the Great Lakes region

    Science.gov (United States)

    Kurth, Valerie J.; Bradford, John B.; Slesak, Robert A.; D'Amato, Anthony W.

    2014-01-01

    Contemporary forest management practices are increasingly designed to optimize novel objectives, such as maximizing biomass feedstocks and/or maintaining ecological legacies, but many uncertainties exist regarding how these practices influence forest carbon (C) cycling. We examined the responses of soil respiration (Rs) to biomass harvesting and green-tree retention in an effort to empirically assess their impacts on C cycling. We measured Rs and soil microclimatic variables over four growing seasons following implementation of these management practices using a fully replicated, operational-scale experiment in aspen-dominated forests in northern Minnesota. Treatments included three levels of biomass removal within harvested areas: whole-tree harvest (no slash deliberately retained), 20% slash retained, and stem-only harvest (all slash retained), and two levels of green-tree retention: 0.1 ha aggregate or none. The relative amount of biomass removed had a negligible effect on Rs in harvested areas, but treatment effects were probably obscured by heterogeneous slash configurations and rapid post-harvest regeneration of aspen in all of the treatments. Discrete measurements of Rs and soil temperature within green-tree aggregates were not discernible from surrounding harvested areas or unharvested control stands until the fourth year following harvest, when Rs was higher in unharvested controls than in aggregates and harvested stands. Growing season estimates of Rs showed that unharvested control stands had higher Rs than both harvested stands and aggregates in the first and third years following harvest. Our results suggest that retention of larger forest aggregates may be necessary to maintain ecosystem-level responses similar to those in unharvested stands. Moreover, they highlight the innate complexity of operational-scale research and suggest that the initial impacts of biomass harvest on Rs may be indiscernible from traditional harvest in systems where incidental

  7. A study on the use and modeling of geographical information system for combating forest crimes: an assessment of crimes in the eastern Mediterranean forests.

    Science.gov (United States)

    Pak, Mehmet; Gülci, Sercan; Okumuş, Arif

    2018-01-06

    This study focuses on the geo-statistical assessment of spatial estimation models in forest crimes. Used widely in the assessment of crime and crime-dependent variables, geographic information system (GIS) helps the detection of forest crimes in rural regions. In this study, forest crimes (forest encroachment, illegal use, illegal timber logging, etc.) are assessed holistically and modeling was performed with ten different independent variables in GIS environment. The research areas are three Forest Enterprise Chiefs (Baskonus, Cinarpinar, and Hartlap) affiliated to Kahramanmaras Forest Regional Directorate in Kahramanmaras. An estimation model was designed using ordinary least squares (OLS) and geographically weighted regression (GWR) methods, which are often used in spatial association. Three different models were proposed in order to increase the accuracy of the estimation model. The use of variables with a variance inflation factor (VIF) value of lower than 7.5 in Model I and lower than 4 in Model II and dependent variables with significant robust probability values in Model III are associated with forest crimes. Afterwards, the model with the lowest corrected Akaike Information Criterion (AIC c ), and the highest R 2 value was selected as the comparison criterion. Consequently, Model III proved to be more accurate compared to other models. For Model III, while AIC c was 328,491 and R 2 was 0.634 for OLS-3 model, AIC c was 318,489 and R 2 was 0.741 for GWR-3 model. In this respect, the uses of GIS for combating forest crimes provide different scenarios and tangible information that will help take political and strategic measures.

  8. Forest offence types, trends and lapses : case study of the Nkawie Forest District of Ghana from 2005-2010

    NARCIS (Netherlands)

    Derkyi, M.A.A.; Dietz, A.J.

    2014-01-01

    The documented analysis of the forest offences revealed eight forest offence types with prevalent cases being chainsaw milling, illegal logging and illegal farming. Between 2005 and 2010, the district recorded 121 offences with more offences occurring in the on-reserve areas than in the off-reserve

  9. A STUDY OF THE NEED FOR A JUNIOR COLLEGE IN THE SALT LAKE METROPOLITAN AREA.

    Science.gov (United States)

    SMITH, RALPH B.

    A POPULATION INCREASE OF 71 PERCENT IS EXPECTED IN UTAH BETWEEN 1960 AND 1980. THE GREATEST GROWTH IS EXPECTED IN THE SALT LAKE METROPOLITAN AREA. THE COLLEGE AGE GROUP (18 TO 21 YEARS) WILL INCREASE BY 80 PERCENT BETWEEN 1960 AND 1970. IF CONSERVATIVE ESTIMATES ARE USED, THE PROPOSED JUNIOR COLLEGE COULD EXPECT AN ENROLLMENT OF APPROXIMATELY…

  10. Air pollution studies in Chicago considering lake breeze events and land use

    Science.gov (United States)

    Schmeling, M.; Treering, D. J.

    2008-12-01

    Trace elemental, ionic species and reactive trace gases were monitored and measured in Chicago air during the summers of 2002 to 2005. Weather data obtained for the same time periods provided information about major wind patterns. Sampling times and duration were selected to coincide with lake breezes, which occur with highest frequency in summer. Lake breezes were observed between 14 and 47 percent of total collection days per summer and appeared to be more frequent in the cooler summers of 2003 and 2004. Depending on the predominant wind direction on the day before, pollutants increased briefly during a lake breeze event. On days without the occurrence of a lake breeze, it was found that the highest concentrations of pollutants were transported by southerly wind currents. Some major sources, such as brick and cement manufacturing, steel industry and heavy road traffic, lay in the path of this wind current. Chicago area land use and transportation maps were analyzed using a Geographic Information System (GIS) to identify major industrial complexes, intermodal terminals, highways and railroads. We also included demographic information in the GIS maps to analyze whether certain population groups are disproportionally exposed to air pollution. Our results will not only be interesting for the science community, but also to policy makers when considering air pollutant exposure and are expected to inform decisions regarding air pollution policy in the future.

  11. Wisconsin's Lake Superior Basin Water Quality Study. Supplement. Technical Report No. 2.

    Science.gov (United States)

    Whisnant, David M., Ed.

    During the period extending from May 1972 through April 1973, an investigation of the overall water quality conditions of streams flowing into Lake Superior from the entire state of Wisconsin was conducted. The goal of this publication was to provide much needed regional information on water quality, drainage basins, pollution sources and loads,…

  12. Cultural Resources in the Southern Lake Erie Basin: A Predictive Study.

    Science.gov (United States)

    1981-01-01

    high base saturation and an argillic horizon, and, in most cases, the maximum soil development. Many of the fine-grained lake-laid sediments are also...Glossary of Soil Terms D- I Argillic horizon: an illuvial horizon in which layer-lattice clays have accumulated by illuviation to a significant extent

  13. Cle Elum Lake Sockeye Salmon Restoration Feasibility Study, 1986-1988 Progress Report.

    Energy Technology Data Exchange (ETDEWEB)

    Flagg, Thomas A.

    1988-10-01

    In 1986, a multi-year project to evaluate the biological feasibility of reestablishing anadromous sockeye salmon (Oncorhynchus nerka) runs to Cle Elum Lake in the Yakima River Basin was established between the Bonneville Power Administration (BPA) and the National Marine Fisheries Service (NMFS). This program involves the capture, spawning, and rearing of disease-free donor stock in 1987 and 1988 and assessment of juvenile outmigration and survival from Cle Elum Lake in 1989 and 1990. Work in 1987--1988 involved collection of adult sockeye salmon from the Lake Wenatchee run and incubation and rearing of progeny as donor stock. In July 1987, 263 adults were captured at the Dryden fishway on the Wenatchee River and transferred to net-pens in Lake Wenatchee. Adults were held approximately 90 days and spawned, and the eggs were transferred to a quarantine hatchery. Pre-spawning survival was 95.1%, and all spawners were certified as being free of Infectious Hematopoietic Necrosis (IHN) and other replicating viruses. Egg viability averaged about 40%; however, eyed egg to hatch survival was over 99%. Juveniles are being reared in quarantine, and survival to date is about 92%. The NMFS currently has over 131,000 fry (0.7 g average weight) in culture. Fry have been certified twice (at 0.12 g and 0.25 g average weight) as being free of IHN and other replicating viruses. Viral certification will continue throughout rearing. 13 refs., 4 figs., 3 tabs.

  14. The last snapshot of natural pelagic fish assemblage in Lake Turkana, Kenya: A hydroacoustic study

    Czech Academy of Sciences Publication Activity Database

    Muška, Milan; Vašek, Mojmír; Modrý, David; Jirků, Miloslav; Ojwang, W. O.; Malala, J. O.; Kubečka, Jan

    2012-01-01

    Roč. 38, č. 1 (2012), s. 98-106 ISSN 0380-1330 R&D Projects: GA AV ČR(CZ) KJB600960813 Institutional support: RVO:60077344 Keywords : African lakes * acoustics * fish distribution * endorheic basin * lates Subject RIV: EH - Ecology, Behaviour Impact factor: 2.309, year: 2012

  15. Studies on the sediments of Vembanad Lake, Kerala State: Part I - Distribution of organic matter

    Digital Repository Service at National Institute of Oceanography (India)

    Murty, P.S.N.; Veerayya, M.

    in their Ni and Cu contents as compared to fine-grained sediments in other parts of the lake and (5) Fe, Mn, Ni, Cu and Co bear significant relationship with organic matter of the sediments. Distribution patterns of elements in the non-estuarine region...

  16. Governance in a beach seine fishery : a case study from Lake Victoria, Tanzania

    NARCIS (Netherlands)

    Medard, M.; Dijk, van J.W.M.; Hebinck, P.; Geheb, K.

    2016-01-01

    Beach seine gear is one of the prominent fishing gears in Nile Perch fishery. Before Nile Perch was introduced to the lake, beach seines the species targeted with beach seine were Tilapia, Bagrus, Haplochromis, Protopterus and Labeo. In 1994, beach seines were banned in Tanzania and by 2004, this

  17. Comparative study on bacterial carbon sources in lake sediments: the role of methanotrophy

    NARCIS (Netherlands)

    Steger, K.; Premke, K.; Gudasz, C.; Boschker, H.T.S.; Tranvik, L.J.

    2015-01-01

    Methane-derived carbon can be important in both benthic and pelagic food webs.Either generated in the anaerobic layers of the sediment or in the anaerobic hypolimnion of stratifiedeutrophic lakes, methane is an excellent carbon source for aerobic methanotrophic bacteria.The very negative methane

  18. An economic inquisition of water quality trading programs, with a case study of Jordan Lake, NC.

    Science.gov (United States)

    Motallebi, Marzieh; Hoag, Dana L; Tasdighi, Ali; Arabi, Mazdak; Osmond, Deanna L

    2017-05-15

    A water quality trading (WQT) program was promulgated in North Carolina to address water quality issues related to nutrients in the highly urbanizing Jordan Lake Watershed. Although WQT programs are appealing in theory, the concept has not proved feasible in several attempts between point and nonpoint polluters in the United States. Many application hurdles that create wedges between success and failure have been evaluated in the literature. Most programs, however, face multiple hurdles; eliminating one may not clear a pathway to success. Therefore, we identify and evaluate the combined impact of four different wedges including baseline, transaction cost, trading ratio, and trading cost in the Jordan Lake Watershed program. Unfortunately, when applied to the Jordan Lake program, the analysis clearly shows that a traditional WQT program will not be feasible or address nutrient management needs in a meaningful way. The hurdles individually would be difficult to overcome, but together they appear to be unsurmountable. This analysis shows that there is enough information to pre-identify potential hurdles that could inform policy makers where, and how, the concept might work. It would have saved time, energy, and financial resources if North Carolina had done so before embarking to implement their program in the Jordan Lake Watershed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Reconstruction of historical atmospheric Pb using Dutch urban lake sediments: A Pb isotope study

    NARCIS (Netherlands)

    Walraven, N.; van Os, B.J.H.; Klaver, G.Th.; Middelburg, J.J.; Davies, G.R.

    2014-01-01

    Lake sediments provide a record of atmospheric Pb deposition and changes in Pb isotope composition. To our knowledge, such an approach has not previously been performed in The Netherlands or linked to national air monitoring data. Results are presented for Pb content and isotope composition of 137Cs

  20. Prediction Of Students’ Learning Study Periode By Using Random Forest Method (Case Study: Stikom Bali

    Directory of Open Access Journals (Sweden)

    I Made Budi Adnyana

    2016-10-01

    Full Text Available Graduation on time is one of the assessment elements of the college accreditation. Furthermore, graduation on time is an important issue because it indicates an effectiveness of college. Academic division of STIKOM Bali face many difficulties on predicting student graduation time because lack of information and analysis. Predictions of graduation time can help academic division in making appropriate strategy to shorten the study time. Data mining can be applied on this prediction problems using random forest classification methods. Random forest is a collection of of several tree, where each tree dependent on the pixels on each vector that selected randomly and independent .Sample data obtained from academic division of STIKOM Bali. This research use sample data of last 2 years graduated students, such as IPK, SKS, the number of inactive, and study time. The classification output consists of 2 class, “graduate on time” and “graduate over the time”. From the experimental result, 83.54 % accuracy value obtained.