WorldWideScience

Sample records for forested watershed kawagama

  1. Water cycle observations in forest watersheds of Cambodia

    Science.gov (United States)

    Shimizu, A.; Tamai, K.; Kabeya, N.; Shimizu, T.; Iida, S. I.

    2015-12-01

    The Lower Mekong River flows through Cambodia, where forests cover ~60% of the country and are believed to have a marked effect on the water cycle. These tropical seasonal forests in the Cambodian flat lands are very precious in the Indochinese Peninsula as few forests of this type remain. However, few hydrological observations have been conducted in these areas. In Cambodia, deciduous and evergreen forests make up 42% and 33% of the total forest area, respectively. We established experimental watersheds both in deciduous and evergreen forests containing meteorological observation towers in Cambodia and collected various observational data since 2003 (O'Krieng, deciduous forest watershed including a 30-m-high observation tower, 2,245 km2; Stung Chinit, evergreen forest watershed including a 60-m-high observation tower, 3,700 km2 including three small watersheds). The basic data from these sites included various kinds of information related to the composition of vegetation, soil characteristics, etc. Hydrologic data was collected and linked to the above data; the main hydrologic research results follow. The water budget for each watershed was determined using an observational rainfall and runoff dataset. The evapotranspiration rate in an evergreen forest was obtained using various observational methods including the Bowen energy-balance ratio and the bandpass eddy covariance method. The annual evapotranspiration of evergreen forests, estimated using the Bowen energy-balance ratio method and water balance, was about 1100-1200 mm, corresponding to 70-80% of annual rainfall. While considering the importance of the presence of evergreen forest, we conducted sap flow measurements to analyze the transpiration process that maintains water uptake through root systems that reach to depths exceeding 8 m. Characteristics of the evaporation from the forest floor that form an important element of the evaporation system were estimated in both evergreen and deciduous forests.

  2. Hydrological processes of reference watersheds in Experimental Forests, USA

    Science.gov (United States)

    Devendra Amatya; John Campbell; Pete Wohlgemuth; Kelly Elder; Stephen Sebestyen; Sherri Johnson; Elizabeth Keppeler; Mary Beth Adams; Peter Caldwell; D. Misra

    2016-01-01

    Long-term research at small, gauged, forested watersheds within the USDA Forest Service, Experimental Forest and Range network (USDA-EFR) has contributed substantially to our current understanding of relationships between forests and streamflow (Vose et al., 2014). Many of these watershed studies were established in the early to mid-20th century and have been used to...

  3. Long-term flow dynamics of three coastal experimental forested watersheds

    Science.gov (United States)

    Devendra M. Amatya; Artur Radecki-Pawlik

    2005-01-01

    Three 1st2nd, and 3rd order experimental forested watersheds located within Francis Marion National Forest in Coastal South Carolina were monitored for rainfall and stream outflows. These watersheds were WS80, a pine-hardwood forest (206 ha); WS79 a predominantly pine forest (500 ha); and WS78, a...

  4. Risk of impaired condition of watersheds containing National Forest lands

    Science.gov (United States)

    Thomas C Brown; Pamela Froemke

    2010-01-01

    We assessed the risk of impaired condition of the nearly 3700 5th-level watersheds in the contiguous 48 states containing the national forests and grasslands that make up the U.S. Forest Service's National Forest System (NFS). The assessment was based on readily available, relatively consistent nationwide data sets for a series of indicators representing watershed...

  5. [Regulation effect of forest vegetation on watershed runoff in the Loess Plateau].

    Science.gov (United States)

    Huang, Mingbin; Liu, Xianzhao

    2002-09-01

    The runoff and rainfall data of typical forested and non-forested watersheds in Ziwuling region, which is located in the hinterland of the Loess Plateau, were used to analyze their annual runoff variation comparatively. The result showed that the annual distribution of runoff in forested watersheds was uniform, compared with that in non-forested watersheds. The total runoff in flood season decreased by 8.88 mm and 7.1 mm. Regression analyses between runoff in dried-up season and rainfall in flood season or in dried-up season showed that the rainfall in flood season in forested watersheds could be changed into underground runoff by forest vegetation, and increased the runoff in dried-up season. The annual variation of runoff also indicated that the total effect of forest vegetation on dried-up runoff complement from October to December was 1.69 mm and 0.5 mm, and that from January to May was not significant.

  6. Impacts of forest changes on hydrology: a case study of large watersheds in the upper reaches of Minjiang River watershed in China

    Science.gov (United States)

    Cui, X.; Liu, S.; Wei, X.

    2012-11-01

    Quantifying the effects of forest changes on hydrology in large watersheds is important for designing forest or land management and adaptation strategies for watershed ecosystem sustainability. Minjiang River watershed, located in the upper reach of the Yangtze River basin, plays a strategic role in the environmental protection and economic and social well-being for both the watershed and the entire Yangtze River basin. The watershed lies in the transition zone from Sichuan Basin to Qinghai-Tibet Plateau with a size of 24 000 km2. Due to its strategic significance, severe historic deforestation and high sensitivity to climate change, the watershed has long been recognized as one of the highest priority watersheds in China for scientific research and resource management. The purpose of this review paper is to provide a state-of-the-art summary on what we have learned from several recently completed research programs (one of them known as "973 of the China National Major Fundamental Science" from 2002 to 2008). This summary paper focused on how land cover or forest change affected hydrology at both forest stand and watershed scales in this large watershed. Inclusion of two different spatial scales is useful, because the results from a small spatial scale (e.g. forest stand level) can help interpret the findings on a large spatial scale. Our review suggests that historic forest harvesting or land cover change has caused significant water yield increase due to reduction of forest canopy interception and evapotranspiration caused by removal of forest vegetation on both spatial scales. The impact magnitude caused by forest harvesting indicates that the hydrological effects of forest or land cover changes can be as important as those caused by climate change, while the opposite impact directions suggest their offsetting effects on water yield in the Minjiang River watershed. In addition, different types of forests have different magnitudes of evapotranspiration (ET), with

  7. Impacts of forest changes on hydrology: a case study of large watersheds in the upper reaches of Minjiang River watershed in China

    Directory of Open Access Journals (Sweden)

    X. Cui

    2012-11-01

    Full Text Available Quantifying the effects of forest changes on hydrology in large watersheds is important for designing forest or land management and adaptation strategies for watershed ecosystem sustainability. Minjiang River watershed, located in the upper reach of the Yangtze River basin, plays a strategic role in the environmental protection and economic and social well-being for both the watershed and the entire Yangtze River basin. The watershed lies in the transition zone from Sichuan Basin to Qinghai-Tibet Plateau with a size of 24 000 km2. Due to its strategic significance, severe historic deforestation and high sensitivity to climate change, the watershed has long been recognized as one of the highest priority watersheds in China for scientific research and resource management. The purpose of this review paper is to provide a state-of-the-art summary on what we have learned from several recently completed research programs (one of them known as "973 of the China National Major Fundamental Science" from 2002 to 2008. This summary paper focused on how land cover or forest change affected hydrology at both forest stand and watershed scales in this large watershed. Inclusion of two different spatial scales is useful, because the results from a small spatial scale (e.g. forest stand level can help interpret the findings on a large spatial scale. Our review suggests that historic forest harvesting or land cover change has caused significant water yield increase due to reduction of forest canopy interception and evapotranspiration caused by removal of forest vegetation on both spatial scales. The impact magnitude caused by forest harvesting indicates that the hydrological effects of forest or land cover changes can be as important as those caused by climate change, while the opposite impact directions suggest their offsetting effects on water yield in the Minjiang River watershed. In addition, different types of forests have different magnitudes of

  8. The US Forest Service Watershed Condition Classification: Status and Path Forward

    Science.gov (United States)

    Levinson, D. H.; Carlson, C. P.; Eberle, M. B.

    2017-12-01

    The US Forest Service Watershed Condition Classification (WCC) was developed as a tool to characterize the condition or health of watersheds on National Forests and Grasslands and assist the Agency in prioritizing actions to restore or maintain the condition of specified watersheds. After a number of years of exploring alternative approaches to assessing the health or condition of watersheds, the WCC and the associated Watershed Condition Framework were developed in response to concerns raised by the US Office of Management and Budget that the Forest Service was not able to demonstrate success in restoring watersheds on a national scale. The WCC was initially applied in 2011 to the roughly 15,000 HUC12 watersheds with an area of Forest Service management of 5% or greater. This initial watershed classification found that 52% (or 7,882) were Functioning Properly (Class 1), 45% (or 6,751) were Functioning at Risk (Class 2), and 3% (or 431) had Impaired Function (Class 3). The basic model used in the WCC was intended to provide a reconnaissance-level evaluation of watershed condition through the use of a systematic, flexible means of classifying and comparing watersheds based on a core set of national watershed condition indicators. The WCC consists of 12 indicators in four major process categories: (1) aquatic physical, (2) aquatic biological, (3) terrestrial physical, and (4) terrestrial biological. Each of the indicators is informed by one or more attributes. The attributes fall into three primary categories: numeric, descriptive, and map-derived, each of which is to be interpreted by an interdisciplinary team at the unit level. The descriptive and map-derived attributes are considered to be semi-quantitative or based on professional judgement of the team. The original description of the attributes anticipated that many of them would be improved as better data and information become available. With the advances in geographic information systems and remote sensing

  9. Hurricane impacts on a pair of coastal forested watersheds: implications of selective hurricane damage to forest structure and streamflow dynamics

    Science.gov (United States)

    Jayakaran, A. D.; Williams, T. M.; Ssegane, H.; Amatya, D. M.; Song, B.; Trettin, C. C.

    2014-03-01

    Hurricanes are infrequent but influential disruptors of ecosystem processes in the southeastern Atlantic and Gulf coasts. Every southeastern forested wetland has the potential to be struck by a tropical cyclone. We examined the impact of Hurricane Hugo on two paired coastal South Carolina watersheds in terms of streamflow and vegetation dynamics, both before and after the hurricane's passage in 1989. The study objectives were to quantify the magnitude and timing of changes including a reversal in relative streamflow difference between two paired watersheds, and to examine the selective impacts of a hurricane on the vegetative composition of the forest. We related these impacts to their potential contribution to change watershed hydrology through altered evapotranspiration processes. Using over 30 years of monthly rainfall and streamflow data we showed that there was a significant transformation in the hydrologic character of the two watersheds - a transformation that occurred soon after the hurricane's passage. We linked the change in the rainfall-runoff relationship to a catastrophic change in forest vegetation due to selective hurricane damage. While both watersheds were located in the path of the hurricane, extant forest structure varied between the two watersheds as a function of experimental forest management techniques on the treatment watershed. We showed that the primary damage was to older pines, and to some extent larger hardwood trees. We believe that lowered vegetative water use impacted both watersheds with increased outflows on both watersheds due to loss of trees following hurricane impact. However, one watershed was able to recover to pre hurricane levels of evapotranspiration at a quicker rate due to the greater abundance of pine seedlings and saplings in that watershed.

  10. 78 FR 21590 - Coconino National Forest; Arizona; Flagstaff Watershed Protection Project

    Science.gov (United States)

    2013-04-11

    ... watersheds around Flagstaff. Specifically, two key areas have been identified for analysis and treatment... Mary Watershed. The FWPP analysis area includes portions of the Coconino National Forest that have... Watershed Protection Project, and is participating in the planning and analysis process. Responsible...

  11. Hydrologic influences of forest vegetation in a changing world: Learning from Forest Service experimental forests, ranges, and watersheds

    Science.gov (United States)

    Thomas E. Lisle; Mary Beth Adams; Leslie M. Reid; Kelly Elder

    2010-01-01

    The importance of forests in providing reliable sources of clean water cannot be underestimated. Therefore, there is a pressing need to understand how hydrologic systems function in forested ecosystems, in response to a variety of traditional and novel stressors and environments. Long-term watershed research on Experimental Forests and Ranges (EFRs) of the Forest...

  12. Export of Dissolved Organic Carbon following Prescribed Fire on Forested Watersheds: Implications for Watershed Management for Drinking Water Supply

    Science.gov (United States)

    Zhang, W.; Olivares, C. I.; Uzun, H.; Erdem, C. U.; Trettin, C.; Liu, Y.; Robinson, E. R.; Karanfil, T.; Chow, A. T.

    2016-12-01

    Detrital material in forest watersheds is the major terrestrial source of dissolved organic matter (DOM) and disinfection byproduct (DBP) precursors in surface source waters, but it is also the fuel for forest fires. Prescribed fire, as a fuel reduction technique is intended to reduce the amount of forest detritus, and therefore the risk of wildfire. Accordingly, periodic prescribed fire can reduce the accumulation of detritus on forest floor and the amount of DOM export after forest treatments. To evaluate the effects of prescribed fire on water quality, we conducted a controlled study on a paired first-order watershed system that includes a 160 ha treatment watershed (WS77) and 200 ha control watershed (WS80) on the Santee Experimental Forest, near Charleston South Carolina. WS77 has been used for prescribed fire research since the 1960's, the current experimental burn occurred on April, 2016. WS80 has not been managed or burned for at least 55 years. Gauging stations were equipped with in-situ TOC sensors and flow-proportional water samplers for monitoring temporal trends on water quality. Water samples taken from the first runoff event from both watersheds including rising limb, peak discharge, and falling limb were used for detailed chemical characterizations including DOC and nutrient concentrations, coagulation efficiency, and DBP formation such as trihalomethanes (THMs) and halocacetic acids (HAAs) from chlorination as well as N-nitrosodimethylamine (NDMA) from chlorination, and chemical formula assignment on DOM using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR-MS) before and after chlorination and chloramination. Preliminary FT-ICR-MS data shows that DOM chemical compositions are different between raw samples collected from WS77 and WS80. Chlorination resulted in a shift toward lower molecular mass compared to the raw materials. While chloramination did not cause a drastic mass shift, such a treatment also produced DOM moieties

  13. Annual evapotranspiration of a forested wetland watershed, SC

    Science.gov (United States)

    Devendra M. Amatya; Carl Trettin

    2007-01-01

    In this study, hydro-meteorological data collected from 1 964 to 1 9 76 on an approximately 5, 000 ha predominantly forested coastal watershed (Turkey Creek) at the Francis Marion National Forest near Charleston, SC were analyzed to estimate annual evapotranspiration (E T) using four different empirical methods. The first one, reported by Zhang et a/. (2001), that...

  14. Assessing the Impact of Forest Change and Climate Variability on Dry Season Runoff by an Improved Single Watershed Approach: A Comparative Study in Two Large Watersheds, China

    Directory of Open Access Journals (Sweden)

    Yiping Hou

    2018-01-01

    Full Text Available Extensive studies on hydrological responses to forest change have been published for centuries, yet partitioning the hydrological effects of forest change, climate variability and other factors in a large watershed remains a challenge. In this study, we developed a single watershed approach combining the modified double mass curve (MDMC and the time series multivariate autoregressive integrated moving average model (ARIMAX to separate the impact of forest change, climate variability and other factors on dry season runoff variation in two large watersheds in China. The Zagunao watershed was examined for the deforestation effect, while the Meijiang watershed was examined to study the hydrological impact of reforestation. The key findings are: (1 both deforestation and reforestation led to significant reductions in dry season runoff, while climate variability yielded positive effects in the studied watersheds; (2 the hydrological response to forest change varied over time due to changes in soil infiltration and evapotranspiration after vegetation regeneration; (3 changes of subalpine natural forests produced greater impact on dry season runoff than alteration of planted forests. These findings are beneficial to water resource and forest management under climate change and highlight a better planning of forest operations and management incorporated trade-off between carbon and water in different forests.

  15. Curve Numbers for Nine Mountainous Eastern United States Watersheds: Seasonal Variation and Forest Cutting

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    Many engineers and hydrologists use the curve number method to estimate runoff from ungaged watersheds; however, the method does not explicitly account for the influence of season or forest cutting on runoff. This study of observed rainfall and runoff for small, forested watershe...

  16. The development and use of best practices in forest watersheds using GIS and simulation models

    Science.gov (United States)

    Steven G. McNulty; Ge Sun

    1998-01-01

    Forest watersheds provide timber and water, wildlife and fisheries habitat, and recreational opportunities. However, not an entire watershed is equally suited for each activity. Steeper slopes may be better left forested and used for wildlife habitat, while more gentle slopes of the watershed could be used for timber production. Logging steep slopes can lead to soil...

  17. Bridging the gap between ecosystem theory and forest watershed management

    Science.gov (United States)

    Jackson Webster; Wayne Swank; James Vose; Jennifer Knoepp; Katherine Elliott

    2014-01-01

    The history of forests and logging in North America provides a back drop for our study of Watershed (WS) 7. Prior to European settlement, potentially commercial forests covered approximately 45% of North America, but not all of it was the pristine, ancient forest that some have imagined. Prior to 1492, Native Americans had extensive settlements throughout eastern...

  18. The cumulative effects of forest disturbance and climate variability on streamflow components in a large forest-dominated watershed

    Science.gov (United States)

    Li, Qiang; Wei, Xiaohua; Zhang, Mingfang; Liu, Wenfei; Giles-Hansen, Krysta; Wang, Yi

    2018-02-01

    Assessing how forest disturbance and climate variability affect streamflow components is critical for watershed management, ecosystem protection, and engineering design. Previous studies have mainly evaluated the effects of forest disturbance on total streamflow, rarely with attention given to its components (e.g., base flow and surface runoff), particularly in large watersheds (>1000 km2). In this study, the Upper Similkameen River watershed (1810 km2), an international watershed situated between Canada and the USA, was selected to examine how forest disturbance and climate variability interactively affect total streamflow, baseflow, and surface runoff. Baseflow was separated using a combination of the recursive digital filter method and conductivity mass balance method. Time series analysis and modified double mass curves were then employed to quantitatively separate the relative contributions of forest disturbance and climate variability to each streamflow component. Our results showed that average annual baseflow and baseflow index (baseflow/streamflow) were 113.3 ± 35.6 mm year-1 and 0.27 for 1954-2013, respectively. Forest disturbance increased annual streamflow, baseflow, and surface runoff of 27.7 ± 13.7 mm, 7.4 ± 3.6 mm, and 18.4 ± 12.9 mm, respectively, with its relative contributions to the changes in respective streamflow components being 27.0 ± 23.0%, 29.2 ± 23.1%, and 25.7 ± 23.4%, respectively. In contrast, climate variability decreased them by 74.9 ± 13.7 mm, 17.9 ± 3.6 mm, and 53.3 ± 12.9 mm, respectively, with its relative contributions to the changes in respective streamflow components being 73.0 ± 23.0%, 70.8 ± 23.1% and 73.1 ± 23.4%, respectively. Despite working in opposite ways, the impacts of climate variability on annual streamflow, baseflow, and surface runoff were of a much greater magnitude than forest disturbance impacts. This study has important implications for the protection of aquatic habitat, engineering design, and

  19. Development of watershed hydrologic research at Santee Experimental Forest, coastal South Carolina

    Science.gov (United States)

    Devendra Amatya; Carl Trettin

    2007-01-01

    Managing forested wetland landscapes for water quality improvement and productivity requires a detailed understanding of functional linkages between ecohydrological processes and management practices. Watershed studies are being conducted at USDA Forest Service Santee Experimental Forest, South Carolina, to understand the fundamental hydrologic and biogeochemical...

  20. Stream carbon dynamics in low-gradient headwaters of a forested watershed

    Science.gov (United States)

    April Bryant-Mason; Y. Jun Xu; Johnny M. Grace

    2013-01-01

    Headwater streams drain more than 70 percent of the total watershed area in the United States. Understanding of carbon dynamics in the headwater systems is of particular relevance for developing best silvicultural practices to reduce carbon export. This study was conducted in a low-gradient, predominantly forested watershed located in the Gulf Coastal Plain region, to...

  1. Impacts of forest changes on hydrology: a case study of large watersheds in the upper reach of Yangtze River Basin

    Science.gov (United States)

    Cui, X.; Liu, S.; Wei, X.

    2012-05-01

    Quantifying the effects of forest changes on hydrology in large watersheds is important for designing forest or land management and adaptation strategies for watershed ecosystem sustainability. Minjiang River watershed located in the upper reach of the Yangtze River Basin plays a strategic role in environmental protection and economic and social wellbeing for both the watershed and the entire Yangtze Basin. The watershed lies in the transition zone from Sichuan Basin to Qinghai-Tibet Plateau with a size of 24 000 km2. Due to its strategic significance, severe historic deforestation and high sensitivity to climate change, the watershed has long been one of the highest priority watersheds in China for scientific research and resource management. The purpose of this review paper is to provide a state-of-the-art summary on what we have learned from several recently-completed research programs (one of them known as "973 of the China National Major Fundamental Science" with funding of 3.5 million USD in 2002 to 2008). This summary paper focused on how land cover or forest change affected hydrology at both forest stand and watershed scales in this large watershed. Inclusion of two different spatial scales is useful because the results from a small spatial scale (e.g. forest stand level) can help interpret the findings at a large spatial scale. Our review suggests that historic forest harvesting or land cover change has caused significant water increase due to reduction of forest canopy interception and evapotranspiration caused by removal of forest vegetation at both spatial scales. The impact magnitudes caused by forest harvesting indicate that the hydrological effects of forest or land cover changes can be as important as those caused by climate change, while the opposite impact directions suggest their offsetting effects on water yields in the Minjiang River watershed. In addition, different types of forests have different magnitudes of ET with old-growth natural

  2. Applying the SWAT hydrologic model on a watershed containing forested karst.

    Science.gov (United States)

    Devendra M. Amatya; Amy E. Edwards

    2009-01-01

    The US Forest Service Center for Forested Wetlands Research is working on a South Carolina Department of Health and Environmental Control (SC DHEC)'s Section 319 Grant Program funded Total Maximum Daily Load (TMDL) project for the watershed of Chapel Branch Creek (CBC) draining to Lake Marion in Santee, South Carolina (Fig. 1)....

  3. Runoff curve numbers for 10 small forested watersheds in the mountains of the eastern United States

    Science.gov (United States)

    Negussie H. Tedela; Steven C. McCutcheon; Todd C. Rasmussen; Richard H. Hawkins; Wayne T. Swank; John L. Campbell; Mary Beth Adams; C. Rhett Jackson; Ernest W. Tollner

    2012-01-01

    Engineers and hydrologists use the curve number method to estimate runoff from rainfall for different land use and soil conditions; however, large uncertainties occur for estimates from forested watersheds. This investigation evaluates the accuracy and consistency of the method using rainfall-runoff series from 10 small forested-mountainous watersheds in the eastern...

  4. Watershed analysis

    Science.gov (United States)

    Alan Gallegos

    2002-01-01

    Watershed analyses and assessments for the Kings River Sustainable Forest Ecosystems Project were done on about 33,000 acres of the 45,500-acre Big Creek watershed and 32,000 acres of the 85,100-acre Dinkey Creek watershed. Following procedures developed for analysis of cumulative watershed effects (CWE) in the Pacific Northwest Region of the USDA Forest Service, the...

  5. Impact of Forest Harvesting and Forest Regeneration on Runoff Dynamics at Watersheds of Central Siberia

    Directory of Open Access Journals (Sweden)

    A. A. Onuchin

    2014-02-01

    Full Text Available In the paper disturbance of Angara river region forests were estimated and peculiarities of forest regeneration after logging and wild fires were analyzed. According to the landscape classification of the regional study, three groups of landscapes differencing on types of forest successions were developed. It was shown that water protective and water regulate functions of the Angara river region forests change under commercial forest harvesting. Comparisons of the inventory and hydrological data detected that hydrological consequences of commercial forest harvesting are dependent on climatic parameters and forest regeneration peculiarities. In the continental climate conditions, when forest regeneration is delayed, snow storms are more active, snow evaporation increases and runoff reduces. In the process of logging sites overgrown with secondary small-leaved forest, snow accumulation increases and runoff increases, exceeding the value of annual runoff at undisturbed watersheds.

  6. Hydrologic and forest management controls on DOC dynamics in the small watersheds of the H.J. Andrews Experimental Forest, OR

    Science.gov (United States)

    Lajtha, K.; Jones, J. A.

    2016-12-01

    Dissolved organic carbon (DOC) export from hillslopes to streams is an important component of the carbon cycle of a catchment and may be a critical source of energy for the aquatic food web in receiving waters. Using a long-term record of DOC and other dissolved nutrients and elements from paired watersheds from the H.J. Andrews Experimental Forest in Oregon, we explored hydrologic, climatic, and land-use controls on seasonal and inter-annual patterns of DOC flux in a seasonally dry ecosystem. Seasonal patterns of DOC flux demonstrated source limitations to DOC export, with DOC concentrations highest immediately following the first rains after a dry summer, and lowest after winter rains. In contrast, more geochemically-controlled elements showed simple dilution-concentration patterns with no seasonal hysteresis. Inter-annual patterns of DOC flux, however, did not provide evidence of source limitation, with DOC flux within a watershed tightly correlated to total discharge but not temperature. Among watersheds, forest harvest, even over 50 years ago, significantly reduced DOC flux but not fluxes of other elements including N; this response was linked to the loading of coarse woody debris to the forest floor. Chemical fingerprinting of DOC revealed that old-growth watersheds had higher fluxes of DOC characteristic of forest floor organic materials, likely delivered to streams through more surficial preferential flow pathways not subject to microbial alteration, respiration, or sorption losses. Taken together these results suggest that the biogeochemical composition of forested streams reflects both current hydrologic patterns and also processes that occurred many decades ago within the catchment.

  7. State factor relationships of dissolved organic carbon and nitrogen losses from unpolluted temperate forest watersheds

    Science.gov (United States)

    Perakis, S.S.; Hedin, L.O.

    2007-01-01

    We sampled 100 unpolluted, old-growth forested watersheds, divided among 13 separate study areas over 5 years in temperate southern Chile and Argentina, to evaluate relationships among dominant soil-forming state factors and dissolved carbon and nitrogen concentrations in watershed streams. These watersheds provide a unique opportunity to examine broad-scale controls over carbon (C) and nitrogen (N) biogeochemistry in the absence of significant human disturbance from chronic N deposition and land use change. Variations in the ratio dissolved organic carbon (DOC) to nitrogen (DON) in watershed streams differed by underlying soil parent material, with average C:N = 29 for watersheds underlain by volcanic ash and basalt versus C:N = 73 for sedimentary and metamorphic parent materials, consistent with stronger adsorption of low C:N hydrophobic materials by amorphous clays commonly associated with volcanic ash and basalt weathering. Mean annual precipitation was related positively to variations in both DOC (range: 0.2-9.7 mg C/L) and DON (range: 0.008-0.135 mg N/L) across study areas, suggesting that variations in water volume and concentration may act synergistically to influence C and N losses across dry to wet gradients in these forest ecosystems. Dominance of vegetation by broadleaf versus coniferous trees had negligible effects on organic C and N concentrations in comparison to abiotic factors. We conclude that precipitation volume and soil parent material are important controls over chemical losses of dissolved organic C and N from unpolluted temperate forest watersheds. Our results raise the possibility that biotic imprints on watershed C and N losses may be less pronounced in naturally N-poor forests than in areas impacted by land use change and chronic N deposition. Copyright 2007 by the American Geophysical Union.

  8. 76 FR 62758 - Wallowa-Whitman and Umatilla National Forests, Oregon Granite Creek Watershed Mining Plans

    Science.gov (United States)

    2011-10-11

    ... environmental analyses for proposed mining Plans in the portions of the Granite Creek Watershed under their... Granite Creek Watershed Mining Plans analysis area that meets the Purpose of and Need for Action. It is... Granite Creek Watershed Mining Plans AGENCY: Forest Service, USDA. ACTION: Notice of intent to prepare an...

  9. Fifty years of watershed research on the Fernow Experimental Forest, WV: effects of forest management and air pollution on hardwood forests

    Science.gov (United States)

    M.B. Adams; P.J. Edwards; J.N. Kochenderfer; F. Wood

    2004-01-01

    In 1951, stream gaging was begun on five small headwater catchments on the Fernow Experimental Forest in West Virginia, to study the effects of forest management activities, particularly timber harvesting, on water yield and quality. Results from these watersheds, and others gaged more recently, have shown that annual water yields increase in proportion to the basal...

  10. An ecosystem report on the Panama Canal: Monitoring the status of the forest communities and the watershed

    Science.gov (United States)

    Ibanez, R.; Condit, R.; Angehr, G.; Aguilar, S.; Garcia, T.; Martinez, R.; Sanjur, A.; Stallard, R.; Wright, S.J.; Rand, A.S.; Heckadon, S.

    2002-01-01

    In 1996, the Smithsonian Tropical Research Institute and the Republic of Panama's Environmental Authority, with support from the United States Agency for International Development, undertook a comprehensive program to monitor the ecosystem of the Panama Canal watershed. The goals were to establish baseline indicators for the integrity of forest communities and rivers. Based on satellite image classification and ground surveys, the 2790 km2 watershed had 1570 km2 of forest in 1997, 1080 km2 of which was in national parks and nature monuments. Most of the 490 km2 of forest not currently in protected areas lies along the west bank of the Canal, and its management status after the year 2000 turnover of the Canal from the U.S. to Panama remains uncertain. In forest plots designed to monitor forest diversity and change, a total of 963 woody plant species were identified and mapped. We estimate there are a total of 850-1000 woody species in forests of the Canal corridor. Forests of the wetter upper reaches of the watershed are distinct in species composition from the Canal corridor, and have considerably higher diversity and many unknown species. These remote areas are extensively forested, poorly explored, and harbor an estimated 1400-2200 woody species. Vertebrate monitoring programs were also initiated, focusing on species threatened by hunting and forest fragmentation. Large mammals are heavily hunted in most forests of Canal corridor, and there was clear evidence that mammal density is greatly reduced in hunted areas and that this affects seed predation and dispersal. The human population of the watershed was 113 000 in 1990, and grew by nearly 4% per year from 1980 to 1990. Much of this growth was in a small region of the watershed on the outskirts of Panama City, but even rural areas, including villages near and within national parks, grew by 2% per year. There is no sewage treatment in the watershed, and many towns have no trash collection, thus streams near large

  11. Water budgets of two forested watersheds in South Carolina

    Science.gov (United States)

    Ge Sun; Jianbiao Lu; David L. Gartner; Masato Miwa; Carl C. Trettin

    2000-01-01

    Wetland protection, restoration and management require detail information of the water budgets for a particular system. Relatively undisturbed systems with long-term hydrologic records are extremely valuable for developing reference wetlands and detecting effects of management. Two forested flatwoods watersheds in the lower coastal plain of South Carolina have been...

  12. Minimum forest cover required for sustainable water flow regulation of a watershed: a case study in Jambi Province, Indonesia

    Science.gov (United States)

    Tarigan, Suria; Wiegand, Kerstin; Sunarti; Slamet, Bejo

    2018-01-01

    In many tropical regions, the rapid expansion of monoculture plantations has led to a sharp decline in forest cover, potentially degrading the ability of watersheds to regulate water flow. Therefore, regional planners need to determine the minimum proportion of forest cover that is required to support adequate ecosystem services in these watersheds. However, to date, there has been little research on this issue, particularly in tropical areas where monoculture plantations are expanding at an alarming rate. Therefore, in this study, we investigated the influence of forest cover and oil palm (Elaeis guineensis) and rubber (Hevea brasiliensis) plantations on the partitioning of rainfall into direct runoff and subsurface flow in a humid, tropical watershed in Jambi Province, Indonesia. To do this, we simulated streamflow with a calibrated Soil and Water Assessment Tool (SWAT) model and observed several watersheds to derive the direct runoff coefficient (C) and baseflow index (BFI). The model had a strong performance, with Nash-Sutcliffe efficiency values of 0.80-0.88 (calibration) and 0.80-0.85 (validation) and percent bias values of -2.9-1.2 (calibration) and 7.0-11.9 (validation). We found that the percentage of forest cover in a watershed was significantly negatively correlated with C and significantly positively correlated with BFI, whereas the rubber and oil palm plantation cover showed the opposite pattern. Our findings also suggested that at least 30 % of the forest cover was required in the study area for sustainable ecosystem services. This study provides new adjusted crop parameter values for monoculture plantations, particularly those that control surface runoff and baseflow processes, and it also describes the quantitative association between forest cover and flow indicators in a watershed, which will help regional planners in determining the minimum proportion of forest and the maximum proportion of plantation to ensure that a watershed can provide

  13. The public water supply protection value of forests: A watershed-scale ecosystem services based upon total organic carbon

    Science.gov (United States)

    We developed a cost-based methodology to assess the value of forested watersheds to improve water quality in public water supplies. The developed methodology is applicable to other source watersheds to determine ecosystem services for water quality. We assess the value of forest land for source wate...

  14. Quantifying streamflow change caused by forest disturbance at a large spatial scale: A single watershed study

    Science.gov (United States)

    Wei, Xiaohua; Zhang, Mingfang

    2010-12-01

    Climatic variability and forest disturbance are commonly recognized as two major drivers influencing streamflow change in large-scale forested watersheds. The greatest challenge in evaluating quantitative hydrological effects of forest disturbance is the removal of climatic effect on hydrology. In this paper, a method was designed to quantify respective contributions of large-scale forest disturbance and climatic variability on streamflow using the Willow River watershed (2860 km2) located in the central part of British Columbia, Canada. Long-term (>50 years) data on hydrology, climate, and timber harvesting history represented by equivalent clear-cutting area (ECA) were available to discern climatic and forestry influences on streamflow by three steps. First, effective precipitation, an integrated climatic index, was generated by subtracting evapotranspiration from precipitation. Second, modified double mass curves were developed by plotting accumulated annual streamflow against annual effective precipitation, which presented a much clearer picture of the cumulative effects of forest disturbance on streamflow following removal of climatic influence. The average annual streamflow changes that were attributed to forest disturbances and climatic variability were then estimated to be +58.7 and -72.4 mm, respectively. The positive (increasing) and negative (decreasing) values in streamflow change indicated opposite change directions, which suggest an offsetting effect between forest disturbance and climatic variability in the study watershed. Finally, a multivariate Autoregressive Integrated Moving Average (ARIMA) model was generated to establish quantitative relationships between accumulated annual streamflow deviation attributed to forest disturbances and annual ECA. The model was then used to project streamflow change under various timber harvesting scenarios. The methodology can be effectively applied to any large-scale single watershed where long-term data (>50

  15. The hidden treasures of long-term paired watershed monitoring in the forests and grasslands of Arizona, USA

    Science.gov (United States)

    B. Poff; D. G. Neary; V. Henderson; A. Tecle

    2012-01-01

    Beginning in the 1950s, researchers of the United States Department of Agriculture Forest Service established a series of paired watershed studies throughout north-central and eastern Arizona. A total of nine experimental watershed areas were established in the pinyon-juniper and chaparral woodlands, as well as the ponderosa pine and mixed conifer forests. While most...

  16. Evaluating the SWAT model for a low-gradient forested watershed in coastal South Carolina

    Science.gov (United States)

    D.M. Amatya; M.K. Jha.

    2011-01-01

    Modeling the hydrology of low�]gradient forested watersheds on shallow, poorly drained soils of the coastal plain is a challenging task due to complexities in watershed delineation, microtopography, evapotranspiration, runoff generation processes and pathways including flooding and submergence caused by tropical storms, and complexity of vegetation species....

  17. Hydrology and water budget for a forested atlantic coastal plain watershed, South Carolina

    Science.gov (United States)

    Scott V. Harder; Devendra M Amatya; Callahan Timothy J.; Carl C. Trettin; Hakkila Jon

    2007-01-01

    Increases in timber demand and urban development in the Atlantic Coastal Plain over the past decade have motivated studies on the hydrology, water quality, and sustainable management of coastal plain watersheds. However, studies on baseline water budgets are limited for the low-lying, forested watersheds of the Atlantic Coastal Plain. The purpose of this study was to...

  18. Hyrdology and water budget for a forested atlantic coastal plain watershed, South Carolina

    Science.gov (United States)

    Scott V. Harder; Devendra M. Amatya; Timothy J. Callahan; Carl C. Trettin; Jon Hakkila

    2007-01-01

    Increases in timber demand and urban development in the Atlantic Coastal Plain over the past decade have motivated studies on the hydrology, water quality, and sustainable management of coastal plain watersheds. However, studies on baseline water budgets are limited for the low-lying, forested watersheds of the Atlantic Coastal Plain. The purpose of this study was to...

  19. Some observations on precipitation measurement on forested experimental watersheds

    Science.gov (United States)

    Raymond E. Leonard; Kenneth G. Reinhart

    1963-01-01

    Measurement of precipitation on forested experimental watersheds presents difficulties other than those associated with access to and from the gages in all kinds of weather. For instance, the tree canopy must be cleared above the gage. The accepted practice of keeping an unobstructed sky view of 45" around the gage involves considerable tree cutting. On a level...

  20. Integration of a Hydrological Model within a Geographical Information System: Application to a Forest Watershed

    Directory of Open Access Journals (Sweden)

    Dimitris Fotakis

    2014-03-01

    Full Text Available Watershed simulation software used for operational purposes must possess both dependability of results and flexibility in parameter selection and testing. The UBC watershed model (UBCWM contains a wide spectrum of parameters expressing meteorological, geological, as well as ecological watershed characteristics. The hydrological model was coupled to the MapInfo GIS and the software created was named Watershed Mapper (WM. WM is endowed with several features permitting operational utilization. These include input data and basin geometry visualization, land use/cover and soil simulation, exporting of statistical results and thematic maps and interactive variation of disputed parameters. For the application of WM two hypothetical scenarios of forest fires were examined in a study watershed. Four major rainfall events were selected from 12-year daily precipitation data and the corresponding peak flows were estimated for the base line data and hypothetical scenarios. A significant increase was observed as an impact of forest fires on peak flows. Due to its flexibility the combined tool described herein may be utilized in modeling long-term hydrological changes in the context of unsteady hydrological analyses.

  1. Diatom Responses to Watershed Development and Potential Moderating Effects of Near-Stream Forest and Wetland Cover

    Science.gov (United States)

    Watershed development alters hydrology and delivers anthropogenic stressors to streams via pathways affected by impervious cover. We characterized relationships of diatom communities and metrics with upstream watershed % impervious cover (IC) and with riparian % forest and wetlan...

  2. Minimum forest cover required for sustainable water flow regulation of a watershed: a case study in Jambi Province, Indonesia

    Directory of Open Access Journals (Sweden)

    S. Tarigan

    2018-01-01

    Full Text Available In many tropical regions, the rapid expansion of monoculture plantations has led to a sharp decline in forest cover, potentially degrading the ability of watersheds to regulate water flow. Therefore, regional planners need to determine the minimum proportion of forest cover that is required to support adequate ecosystem services in these watersheds. However, to date, there has been little research on this issue, particularly in tropical areas where monoculture plantations are expanding at an alarming rate. Therefore, in this study, we investigated the influence of forest cover and oil palm (Elaeis guineensis and rubber (Hevea brasiliensis plantations on the partitioning of rainfall into direct runoff and subsurface flow in a humid, tropical watershed in Jambi Province, Indonesia. To do this, we simulated streamflow with a calibrated Soil and Water Assessment Tool (SWAT model and observed several watersheds to derive the direct runoff coefficient (C and baseflow index (BFI. The model had a strong performance, with Nash–Sutcliffe efficiency values of 0.80–0.88 (calibration and 0.80–0.85 (validation and percent bias values of −2.9–1.2 (calibration and 7.0–11.9 (validation. We found that the percentage of forest cover in a watershed was significantly negatively correlated with C and significantly positively correlated with BFI, whereas the rubber and oil palm plantation cover showed the opposite pattern. Our findings also suggested that at least 30 % of the forest cover was required in the study area for sustainable ecosystem services. This study provides new adjusted crop parameter values for monoculture plantations, particularly those that control surface runoff and baseflow processes, and it also describes the quantitative association between forest cover and flow indicators in a watershed, which will help regional planners in determining the minimum proportion of forest and the maximum proportion of plantation to ensure that a

  3. Hydrologic processes of forested headwater watersheds across a physiographaic gradient in the southeastern United States

    Science.gov (United States)

    Ge Sun; Johnny Boggs; Steven G. McNulty; Devendra M. Amatya; Carl C. Trettin; Zhaohua Dai; James M. Vose; Ileana B. La Torre Torres; Timothy Callahan

    2008-01-01

    Understanding the hydrologic processes is the first step in making sound watershed management decisions including designing Best Management Practices for nonpoint source pollution control. Over the past fifty years, various forest experimental watersheds have been instrumented across the Carolinas through collaborative studies among federal, state, and private...

  4. Numerical modeling of watershed-scale radiocesium transport coupled with biogeochemical cycling in forests

    Science.gov (United States)

    Mori, K.; Tada, K.; Tawara, Y.; Tosaka, H.; Ohno, K.; Asami, M.; Kosaka, K.

    2015-12-01

    Since the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident, intensive monitoring and modeling works on radionuclide transfer in environment have been carried out. Although Cesium (Cs) concentration has been attenuating due to both physical and environmental half-life (i.e., wash-off by water and sediment), the attenuation rate depends clearly on the type of land use and land cover. In the Fukushima case, studying the migration in forest land use is important for predicting the long-term behavior of Cs because most of the contaminated region is covered by forests. Atmospheric fallout is characterized by complicated behavior in biogeochemical cycle in forests which can be described by biotic/abiotic interactions between many components. In developing conceptual and mathematical model on Cs transfer in forest ecosystem, defining the dominant components and their interactions are crucial issues (BIOMASS, 1997-2001). However, the modeling of fate and transport in geosphere after Cs exports from the forest ecosystem is often ignored. An integrated watershed modeling for simulating spatiotemporal redistribution of Cs that includes the entire region from source to mouth and surface to subsurface, has been recently developed. Since the deposited Cs can migrate due to water and sediment movement, the different species (i.e., dissolved and suspended) and their interactions are key issues in the modeling. However, the initial inventory as source-term was simplified to be homogeneous and time-independent, and biogeochemical cycle in forests was not explicitly considered. Consequently, it was difficult to evaluate the regionally-inherent characteristics which differ according to land uses, even if the model was well calibrated. In this study, we combine the different advantages in modeling of forest ecosystem and watershed. This enable to include more realistic Cs deposition and time series of inventory can be forced over the land surface. These processes are integrated

  5. Modeling precipitation-runoff relationships to determine water yield from a ponderosa pine forest watershed

    Science.gov (United States)

    Assefa S. Desta

    2006-01-01

    A stochastic precipitation-runoff modeling is used to estimate a cold and warm-seasons water yield from a ponderosa pine forested watershed in the north-central Arizona. The model consists of two parts namely, simulation of the temporal and spatial distribution of precipitation using a stochastic, event-based approach and estimation of water yield from the watershed...

  6. Surface runoff generation in a small watershed covered by sugarcane and riparian forest

    Directory of Open Access Journals (Sweden)

    Rafael Pires Fernandes

    2013-12-01

    Full Text Available Since an understanding of how runoff is generated is of great importance to soil conservation, to water availability and to the management of a watershed, the objective of this study was to understand the generation of surface runoff in a watershed covered by sugarcane and riparian forest. Nine surface runoff plots were set up, evenly distributed on the lower, middle and upper slopes. The lower portion was covered by riparian forest. We showed that the average surface runoff coefficient along the slope in the present study was higher than in other studies under different land uses. Furthermore, the surface runoff was higher under sugarcane compared to the riparian forest, especially after sugarcane harvesting. Besides land cover, other factors such as the characteristics of rainfall events, relief and physical soil characteristics such as soil bulk density and saturated hydraulic conductivity influenced the surface runoff generation.

  7. Experimental forest watershed studies contribution to the effect of disturbances on water quality

    Science.gov (United States)

    Daniel G. Neary

    2012-01-01

    The most sustainable and best quality fresh water sources in the world originate in forested watersheds (Dissmeyer 2000, Brooks et al. 2003, Barten and Ernst 2004). The biological, chemical, and physical characteristics of forest soils are particularly well suited to delivering high quality water to streams, and moderating the climatic extremes which affect stream...

  8. EnviroAtlas - Number of Water Markets per HUC8 Watershed, U.S., 2015, Forest Trends' Ecosystem Marketplace

    Science.gov (United States)

    This EnviroAtlas dataset contains polygons depicting the number of watershed-level market-based programs, referred to herein as markets, in operation per 8-digit HUC watershed throughout the United States. The data were collected via surveys and desk research conducted by Forest Trends' Ecosystem Marketplace during 2014 regarding markets operating to protect watershed ecosystem services. Utilizing these data, the number of water market coverage areas overlaying each HUC8 watershed were calculated to produce this dataset. Only water markets identified as operating at the watershed level (i.e., single or multiple watersheds define the market boundaries) were included in the count of water markets per HUC8 watershed. Excluded were water markets operating at the national, state, county, or federal lands level and all water projects. Attribute data include the watershed's 8-digit hydrologic unit code and name, in addition to the watershed-level water market count associated with the watershed. This dataset was produced by Forest Trends' Ecosystem Marketplace to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Addi

  9. Hydrology and water quality of two first order forested watersheds in coastal South Carolina

    Science.gov (United States)

    D.M. Amatya; M. Miwa; C.A. Harrison; C.C. Trettin; G. Sun

    2006-01-01

    Two first-order forested watersheds (WS 80 and WS 77) on poorly drained pine-hardwood stands in the South Carolina Coastal Plain have been monitored since mid-1960s to characterize the hydrology, water quality and vegetation dynamics. This study examines the flow and nutrient dynamics of these two watersheds using 13 years (1 969-76 and 1977-81) of data prior to...

  10. Effects of watershed experiments on water chemistry at the Marcell Experimental Forest. Chapter 14.

    Science.gov (United States)

    Stephen D. Sebestyen; Elon S. Verry

    2011-01-01

    The Marcell Experimental Forest (MEF) was established during the 1960s to study the hydrology and ecology of lowland watersheds where upland mineral soils drain to central peatlands (Boelter and Verry 1977). The effects of seven large-scale manipulations on water chemistry have been studied on the MEF watersheds and the data now span up to four decades. In this chapter...

  11. Effects of Forest Cover Change on Flood Characteristics in the Upper Citarum Watershed

    Directory of Open Access Journals (Sweden)

    Bambang Dwi Dasanto

    2014-12-01

    Full Text Available Information on the effect of forest cover changes on streamflow (river discharge in large-scale catchment is important to be studied. The rate of forest cover change in the Upper Citarum Watershed as a large-scale catchment is high enough to drive streamflow change, such as increase of discharge level, or flood volume. Within the research area, flood would occur when the volume of streamflow exceeded the canal capacity and inundated areas that were normally dry. Therefore, this research focused on identifying the effects of forest cover change on flood events and its distribution. The research consisted of 2 main stages; firstly, building geometric data of river and performing frequency analysis of historical and scenario discharges using an approach of probability distribution; and, secondly, flood inundation mapping using HEC-RAS model. The results showed that forest reduction have affected water yield in the downstream of Upper Citarum Watershed. In each return period, this reduction have increased river discharge level and affected the spread of flooded areas. In 2-year return period, the extent of flood as an impact of forest reduction was estimated to decrease slowly. However, in the return period of more than 2 years, the spread of flooded areas increased sharply. These proved that forest cover reduction would always increase the discharge value, but it did not always expand the inundated area.

  12. Streamwater chemistry and nutrient budgets for forested watersheds in New England: variability and management implications

    Science.gov (United States)

    J.W. Hornbeck; S.W. Bailey; D.C. Buso; J.B. Shanley

    1997-01-01

    Chemistry of precipitation and streamwater and resulting input-output budgets for nutrient ions were determined concurrently for three years on three upland, forested watersheds located within an 80 km radius in central New England. Chemistry of precipitation and inputs of nutrients via wet deposition were similar among the three watersheds and were generally typical...

  13. Effects of climate variability and accelerated forest thinning on watershed-scale runoff in southwestern USA ponderosa pine forests.

    Directory of Open Access Journals (Sweden)

    Marcos D Robles

    Full Text Available The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres of ponderosa pine (Pinus ponderosa forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment and modest when compared to mean annual runoff from the study watersheds (0-3%. Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide.

  14. Effects of climate variability and accelerated forest thinning on watershed-scale runoff in southwestern USA ponderosa pine forests.

    Science.gov (United States)

    Robles, Marcos D; Marshall, Robert M; O'Donnell, Frances; Smith, Edward B; Haney, Jeanmarie A; Gori, David F

    2014-01-01

    The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres) of ponderosa pine (Pinus ponderosa) forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment) and modest when compared to mean annual runoff from the study watersheds (0-3%). Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide.

  15. Effects of Climate Variability and Accelerated Forest Thinning on Watershed-Scale Runoff in Southwestern USA Ponderosa Pine Forests

    Science.gov (United States)

    Robles, Marcos D.; Marshall, Robert M.; O'Donnell, Frances; Smith, Edward B.; Haney, Jeanmarie A.; Gori, David F.

    2014-01-01

    The recent mortality of up to 20% of forests and woodlands in the southwestern United States, along with declining stream flows and projected future water shortages, heightens the need to understand how management practices can enhance forest resilience and functioning under unprecedented scales of drought and wildfire. To address this challenge, a combination of mechanical thinning and fire treatments are planned for 238,000 hectares (588,000 acres) of ponderosa pine (Pinus ponderosa) forests across central Arizona, USA. Mechanical thinning can increase runoff at fine scales, as well as reduce fire risk and tree water stress during drought, but the effects of this practice have not been studied at scales commensurate with recent forest disturbances or under a highly variable climate. Modifying a historical runoff model, we constructed scenarios to estimate increases in runoff from thinning ponderosa pine at the landscape and watershed scales based on driving variables: pace, extent and intensity of forest treatments and variability in winter precipitation. We found that runoff on thinned forests was about 20% greater than unthinned forests, regardless of whether treatments occurred in a drought or pluvial period. The magnitude of this increase is similar to observed declines in snowpack for the region, suggesting that accelerated thinning may lessen runoff losses due to warming effects. Gains in runoff were temporary (six years after treatment) and modest when compared to mean annual runoff from the study watersheds (0–3%). Nonetheless gains observed during drought periods could play a role in augmenting river flows on a seasonal basis, improving conditions for water-dependent natural resources, as well as benefit water supplies for downstream communities. Results of this study and others suggest that accelerated forest thinning at large scales could improve the water balance and resilience of forests and sustain the ecosystem services they provide. PMID

  16. Forest Conversion to Land of Rubber and Palm Oil Farming and Its Effect on Run Off and Soil Erosion in Batang Pelepat Watershed

    Directory of Open Access Journals (Sweden)

    Sunarti

    2008-09-01

    Full Text Available Forest conversion to some land use happened in all watershed, includes Batang Pelepat watershed. The objectives of this research are to know effect of forest conversion to land of rubber (Hevea brasiliensis and palm oil (Elaeis guinensis Jack farming on run off and soil erosion and different of erosion rate on agro technology of rubber and palm oil farming in Batang Pelepat watershed. The research was carried out during 3 months, begin October to December 2006. Run off and soil erosion measured plot with gutter in the lower of plot. Experimental design for this research is randomized complete block design, with land use type as treatment and slope class as replication or block. Data analyzed statistically by variance analysis (F-test and Duncan New Multiple Range Test on confidence 95% (á = 0.05. The results of this research show that area of forest coverage in Batang Pelepat watershed was decreasing. In 1986 this area still 94.50% of watershed area, but in 1994 area of forest only 78.17% and in 2006 forest area 64.20% of watershed area. Forest conversion was carried out to land of rubber and palm oil farming with some actual agro technologies. Land of monoculture rubber I resulted the highest run off and soil erosion more than the other land use type and showed different of run off and soil erosion on land of secondary forest.

  17. Preface: long-term response of a forest watershed ecosystem, clearcutting in the Southern Appalachians

    Science.gov (United States)

    Wayne Swank; Jackson Webster

    2014-01-01

    Our North American forests are no longer the wild areas of past centuries; they are an economic and ecological resource undergoing changes from both natural and management disturbances. A watershed-scale and long-term perspective of forest ecosystem responses is requisite to understanding and predicting cause and effect relationships. This book synthesizes...

  18. Effects of Forest Cover Change on Flood Characteristics in the Upper Citarum Watershed

    Directory of Open Access Journals (Sweden)

    Bambang Dwi Dasanto

    2015-02-01

    Full Text Available Information on the effect of forest cover changes on streamflow (river discharge in large-scale catchment is important to be studied. The rate of forest cover change in the Upper Citarum Watershed as a large-scale catchment is high enough to drive streamflow change, such as increase of discharge level, or flood volume. Within the research area, flood would occur when the volume of streamflow exceeded the canal capacity and inundated areas that were normally dry. Therefore, this research focused on identifying the effects of forest cover change on flood events and its distribution. The research consisted of 2 main stages; firstly, building geometric data of river and performing frequency analysis of historical and scenario discharges using an approach of probability distribution; and, secondly, flood inundation mapping using HEC-RAS model. The results showed that forest reduction have affected water yield in the downstream of Upper Citarum Watershed. In each return period, this reduction have increased river discharge level and affected the spread of flooded areas. In 2-year return period, the extent of flood as an impact of forest reduction was estimated to decrease slowly. However, in the return period of more than 2 years, the spread of flooded areas increased sharply. These proved that forest cover reduction would always increase the discharge value, but it did not always expand the inundated area.Keywords: geometric data, forest cover, water yield, return period

  19. Modeling soil erosion and sediment transport from fires in forested watersheds of the South Carolina Piedmont

    Science.gov (United States)

    Tyler Crumbley; Ge Sun; Steve McNulty

    2007-01-01

    Forested watersheds in the Southeastern U.S. provide high quality water vital to ecosystem integrity and downstream aquatic resources. Excessive sedimentation from human activities in forest streams is of concern to responsible land managers. Prescribed fire is a common treatment applied to Southeastern Piedmont forests and the risk of wildfire is becoming increasingly...

  20. Modeling soil erosion and sediment transport from fires in forested watersheds of the South Carolina Piedmont

    Science.gov (United States)

    Tyler Crumbley; Ge Sun; Steve McNulty

    2008-01-01

    Forested watersheds in the Southeastern U.S. provide high quality water vital to ecosystem integrity and downstream aquatic resources. Excessive sedimentation from human activities in forest streams is of concern to responsible land managers. Prescribed fire is a common treatment applied to Southeastern piedmont forests and the risk of wildfire is becoming increasingly...

  1. Radionuclides deposition and fine sediment transport in a forested watershed, central Japan

    Science.gov (United States)

    Nam, S.; Gomi, T.; Kato, H.; Tesfaye, T.; Onda, Y.

    2011-12-01

    We investigated radionuclides deposition and fine sediment transport in a 13 ha headwater watershed, Tochigi prefecture, located in 98.94 km north of Tokyo. The study site was within Karasawa experimental forest, Tokyo University of Agriculture and Technology. We conducted fingerprinting approach, based on the activities of fallout radionuclides, including caesium-134 (Cs-134) caesium-137 (Cs-137) and excess lead-210 (Pb-210ex). For indentifying specific sources of fine sediment, we sampled tree, soil on forested floor, soil on logging road surface, stream bed and stream banks. We investigated the radionuclides (i.e., as Cs-134, Cs-137 and Pb-210ex) deposition on tree after accident of nuclear power plants on March 11, 2011. We sampled fruits, leaves, branches, stems, barks on Japanese cedar (Sugi) and Japanese cypress (Hinoki). To analyze the samples, gammaray spectrometry was performed at a laboratory at the University of Tsukuba (Tsukuba City, Japan) using n-type coaxial low-energy HPGe gamma detectors (EGC-200-R and EGC25-195-R of EURYSIS Co., Lingolsheim, France) coupled with a multichannel analyzer. We also collected soil samples under the forest canopy in various soil depths from 2, 5, 10, 20, 30 cm along transect of hillslopes. Samples at forest road were collected road segments crossing on the middle section of monitoring watersheds. Fine sediment transport in the streams were collected at the outlet of 13 ha watersheds using integrated suspended sediment samplers. This study indicates the some portion of radio nuclide potentially remained on the tree surface. Part of the deposited radionuclides attached to soil particles and transported to the streams. Most of the fine sediment can be transported on road surface and/or near stream side (riparian zones).

  2. Hydrologic and water quality monitoring on Turkey Creek watershed, Francis Marion National Forest, SC

    Science.gov (United States)

    D.M. Amatya; T.J. Callahan; A. Radecki-Pawlik; P. Drewes; C. Trettin; W.F. Hansen

    2008-01-01

    The re-initiation of a 7,260 ha forested watershed study on Turkey Creek, a 3rd order stream, within the Francis Marion National forest in South Carolina, completes the development of a multi-scale hydrology and ecosystem monitoring framework in the Atlantic Coastal Plain. Hydrology and water quality monitoring began on the Santee Experimental...

  3. Deforestation and fragmentation of natural forests in the upper Changhua watershed, Hainan, China: implications for biodiversity conservation.

    Science.gov (United States)

    Zhai, De-Li; Cannon, Charles H; Dai, Zhi-Cong; Zhang, Cui-Ping; Xu, Jian-Chu

    2015-01-01

    Hainan, the largest tropical island in China, belongs to the Indo-Burma biodiversity hotspot. The Changhua watershed is a center of endemism for plants and birds and the cradle of Hainan's main rivers. However, this area has experienced recent and ongoing deforestation and habitat fragmentation. To quantify habitat loss and fragmentation of natural forests, as well as the land-cover changes in the Changhua watershed, we analyzed Landsat images obtained in 1988, 1995, and 2005. Land-cover dynamics analysis showed that natural forests increased in area (97,909 to 104,023 ha) from 1988 to 1995 but decreased rapidly to 76,306 ha over the next decade. Rubber plantations increased steadily throughout the study period while pulp plantations rapidly expanded after 1995. Similar patterns of land cover change were observed in protected areas, indicating a lack of enforcement. Natural forests conversion to rubber and pulp plantations has a general negative effect on biodiversity, primarily through habitat fragmentation. The fragmentation analysis showed that natural forests area was reduced and patch number increased, while patch size and connectivity decreased. These land-cover changes threatened local biodiversity, especially island endemic species. Both natural forests losses and fragmentation should be stopped by strict enforcement to prevent further damage. Preserving the remaining natural forests and enforcing the status of protected areas should be a management priority to maximize the watershed's biodiversity conservation value.

  4. Quantifying the Relative Contributions of Forest Change and Climatic Variability to Hydrology in Large Watersheds: A Critical Review of Research Methods

    Directory of Open Access Journals (Sweden)

    Xiaohua Wei

    2013-06-01

    Full Text Available Forest change and climatic variability are two major drivers for influencing change in watershed hydrology in forest–dominated watersheds. Quantifying their relative contributions is important to fully understand their individual effects. This review paper summarizes the progress on quantifying the relative contributions of forest or land cover change and climatic variability to hydrology in large watersheds using available case studies. It compared pros and cons of various research methods, identified research challenges and proposed future research priorities. Our synthesis shows that the relative hydrological effects of forest changes and climatic variability are largely dependent on their own change magnitudes and watershed characteristics. In some severely disturbed watersheds, impacts of forest changes or land use changes can be as important as those from climatic variability. This paper provides a brief review on eight selected research methods for this type of research. Because each method or technique has its own strengths and weaknesses, combining two or more methods is a more robust approach than using any single method alone. Future research priorities include conducting more case studies, refining research methods, and considering mechanism-based research using landscape ecology and geochemistry approaches.

  5. Spatial distribution of water erosion risk in a watershed with eucalyptus and Atlantic Forest

    Directory of Open Access Journals (Sweden)

    Junior Cesar Avanzi

    2013-10-01

    Full Text Available The process of water erosion occurs in watersheds throughout the world and it is strongly affected by anthropogenic influences. Thus, the knowledge of these processes is extremely necessary for planning of conservation efforts. This study was performed in an experimental forested watershed in order to predict the average potential annual soil loss by water erosion using the Universal Soil Loss Equation (USLE and a Geographic Information System (GIS, and then compared with soil loss tolerance. All the USLE factors were generated in a distributed approach employing a GIS tool. The layers were multiplied in the GIS framework in order to predict soil erosion rates. Results showed that the average soil loss was 6.2 Mg ha-1 yr-1. Relative to soil loss tolerance, 83% of the area had an erosion rate lesser than the tolerable value. According to soil loss classes, 49% of the watershed had erosion less than 2.5 Mg ha-1 yr-1. However, about 8.7% of the watershed had erosion rates greater than 15 Mg ha-1 yr-1, being mainly related to Plinthosol soil class and roads, thus requiring special attention for the improvement of sustainable management practices for such areas. Eucalyptus cultivation was found to have soil loss greater than Atlantic Forest. Thus, an effort should be made to bring the erosion rates closer to the native forest. Implementation of the USLE model in a GIS framework was found to be a simple and useful tool for predicting the spatial variation of soil erosion risk and identifying critical areas for conservation efforts.

  6. Geoecology of a forest watershed underlain by serpentine in Central Europe

    Science.gov (United States)

    Pavel Krám; Filip Oulehle; Veronika Štedrá; Jakub Hruška; James B. Shanley; Rakesh Minocha; Elena. Traister

    2009-01-01

    The geoecology of a serpentinite-dominated site in the Czech Republic was investigated by rock, soil, water, and plant analyses. The 22-ha Pluhuv Bor watershed is almost entirely forested by a nearly 110-year old plantation of Picea abies (Norway Spruce) mixed with native Pinus sylvestris (Scots Pine) in the highest elevations...

  7. Alterations in land uses based on amendments to the Brazilian Forest Law and their influences on water quality of a watershed.

    Science.gov (United States)

    Rodrigues-Filho, J L; Degani, R M; Soares, F S; Periotto, N A; Blanco, F P; Abe, D S; Matsumura-Tundisi, T; Tundisi, J E; Tundisi, J G

    2015-01-01

    The amendments to the Forest Law proposed by the Brazilian government that allow partial substitution of forested areas by agricultural activities raised deep concern about the integrity of aquatic ecosystems. To assess the impacts of this alteration in land uses on the watershed, diffuse loads of total nitrogen (Nt) and total phosphorus (Pt) were estimated in Lobo Stream watershed, southeastern Brazil, based on export coefficients of the Model of Correlation between Land Use and Water Quality (MQUAL). Three scenarios were generated: scenario 1 (present scenario), with 30-meter-wide permanent preservation areas along the shore of water bodies and 50-meter-radius in springs; scenario 2, conservative, with 100-meter-wide permanent preservation areas along water bodies; and scenario 3, with the substitution of 20% of natural forest by agricultural activities. Results indicate that a suppression of 20% of forest cover would cause an increase in nutrient loads as well as in the trophic state of aquatic ecosystems of the watershed. This could result in losses of ecosystem services and compromise the quality of water and its supply for the basin. This study underlines the importance of forest cover for the maintenance of water quality in Lobo Stream watershed.

  8. Observations of distributed snow depth and snow duration within diverse forest structures in a maritime mountain watershed

    Science.gov (United States)

    Dickerson-Lange, Susan E.; Lutz, James A.; Gersonde, Rolf; Martin, Kael A.; Forsyth, Jenna E.; Lundquist, Jessica D.

    2015-11-01

    Spatially distributed snow depth and snow duration data were collected over two to four snow seasons during water years 2011-2014 in experimental forest plots within the Cedar River Municipal Watershed, 50 km east of Seattle, Washington, USA. These 40 × 40 m forest plots, situated on the western slope of the Cascade Range, include unthinned second-growth coniferous forests, variable density thinned forests, forest gaps in which a 20 m diameter (approximately equivalent to one tree height) gap was cut in the middle of each plot, and old-growth forest. Together, this publicly available data set includes snow depth and density observations from manual snow surveys, distributed snow duration observations from ground temperature sensors and time-lapse cameras, meteorological data collected at two open locations and three forested locations, and forest canopy data from airborne light detection and ranging (LiDAR) data and hemispherical photographs. These colocated snow, meteorological, and forest data have the potential to improve understanding of forest influences on snow processes, and provide a unique model-testing data set for hydrological analyses in a forested, maritime watershed. We present empirical snow depletion curves within forests to illustrate an application of these data to improve subgrid representation of snow cover in distributed modeling.

  9. Effects of forest harvest on stream-water quality and nitrogen cycling in the Caspar Creek watershed

    Science.gov (United States)

    Randy A. Dahlgren

    1998-01-01

    The effects of forest harvest on stream-water quality and nitrogen cycling were examined for a redwood/Douglas-fir ecosystem in the North Fork, Caspar Creek experimental watershed in northern California. Stream-water samples were collected from treated (e.g., clearcut) and reference (e.g., noncut) watersheds, and from various locations downstream from the treated...

  10. The organic nature and atmosphere-climate dependency of nitrogen loss from forest watershed ecosystems

    OpenAIRE

    Brookshire, E. N. J.

    2006-01-01

    In this dissertation I describe how coupled internal cycling and external forcing from the atmosphere and climate can regulate the dynamics of nitrogen (N) loss from forest watersheds. I address three major gaps in our understanding of the global N cycle: 1) the role of dissolved organic N (DON) in internal N cycling in low-N ecosystems; 2) The influence of atmospheric pollution on DON production and loss from forests; and 3) the inherent climate sensitivity of forest N cycling and loss. In...

  11. Watershed management in Myanmar

    International Nuclear Information System (INIS)

    Choi, K.S.

    1993-01-01

    Watershed degradation, watershed management, background of watershed management in Myanmar (condition of watershed, manpower), discussion and recommendation (proposed administrative structure, the need for watershed survey and planning, bottom-up approach) are emphasized. Watershed management, after all can be seen that it is the interphase between the forest, agriculture, soil, wildlife and the local communities

  12. Watershed management in Myanmar

    Energy Technology Data Exchange (ETDEWEB)

    Choi, K S

    1993-10-01

    Watershed degradation, watershed management, background of watershed management in Myanmar (condition of watershed, manpower), discussion and recommendation (proposed administrative structure, the need for watershed survey and planning, bottom-up approach) are emphasized. Watershed management, after all can be seen that it is the interphase between the forest, agriculture, soil, wildlife and the local communities

  13. Comparison of riparian and upland forest stand structure and fuel loads in beetle infested watersheds, southern Rocky Mountains

    Science.gov (United States)

    Kathleen A. Dwire; Robert Hubbard; Roberto Bazan

    2015-01-01

    Extensive outbreaks of mountain pine beetle (MPB), spruce beetle (SB), and other insects are altering forest stand structure throughout western North America, and thereby contributing to the heterogeneity of fuel distribution. In forested watersheds, conifer-dominated riparian forests frequently occur as narrow linear features in the landscape mosaic and contribute to...

  14. A cross-site comparison of factors influencing soil nitrification rates in northeastern USA forested watersheds

    Science.gov (United States)

    Ross, D.S.; Wemple, B.C.; Jamison, A.E.; Fredriksen, G.; Shanley, J.B.; Lawrence, G.B.; Bailey, S.W.; Campbell, J.L.

    2009-01-01

    Elevated N deposition is continuing on many forested landscapes around the world and our understanding of ecosystem response is incomplete. Soil processes, especially nitrification, are critical. Many studies of soil N transformations have focused on identifying relationships within a single watershed but these results are often not transferable. We studied 10 small forested research watersheds in the northeastern USA to determine if there were common factors related to soil ammonification and nitrification. Vegetation varied between mixed northern hardwoods and mixed conifers. Watershed surface soils (Oa or A horizons) were sampled at grid or transect points and analyzed for a suite of chemical characteristics. At each sampling point, vegetation and topographic metrics (field and GIS-based) were also obtained. Results were examined by watershed averages (n = 10), seasonal/watershed averages (n = 28), and individual sampling points (n = 608). Using both linear and tree regression techniques, the proportion of conifer species was the single best predictor of nitrification rates, with lower rates at higher conifer dominance. Similar to other studies, the soil C/N ratio was also a good predictor and was well correlated with conifer dominance. Unlike other studies, the presence of Acer saccharum was not by itself a strong predictor, but was when combined with the presence of Betula alleghaniensis. Topographic metrics (slope, aspect, relative elevation, and the topographic index) were not related to N transformation rates across the watersheds. Although found to be significant in other studies, neither soil pH, Ca nor Al was related to nitrification. Results showed a strong relationship between dominant vegetation, soil C, and soil C/N. ?? 2008 Springer Science+Business Media, LLC.

  15. Soil respiration from four aggrading forested watersheds measured over a quarter century

    Science.gov (United States)

    David C. Coleman; Mark D. Hunter; John Hutton; Steven Pomeroy; Lloyd Swift

    2002-01-01

    Soil respiration was measured in four aggrading, forested second-growth watersheds in the southern Appalachians using an identical method (alkali absorption) at intervals 23 and 24 years apart. Seasonal trends were similar, with mid-summer maxima and winter minima. Amounts of carbon dioxide evolved were higher in the recent measurements (1995) compared to the earlier...

  16. Forest, water and people: The roles and limits of mediation in transforming watershed conflict in Northern Thailand

    Directory of Open Access Journals (Sweden)

    Ahmad Dhiaulhaq

    2017-11-01

    Full Text Available This study focuses on watershed management in Northern Thailand, where conflict over forest, land and water-use is a prevailing problem. A characteristic of watershed conflicts is that they are often multifaceted and involve multiple stakeholders with different interests and values, consequently requiring conflict management approaches that are sustainable in their outcomes, including addressing the underlying causes of the conflicts. Drawing from a case study in Mae Tia Mae Tae watershed in Northern Thailand, this study explores how mediation by external third party can contribute to the transformation of conflicts in the watershed and how the broader institutional contexts in which the conflict is embedded shapes the mediation outcomes. The study suggests that co-creation of mutual understanding and recognition of each party’s socio-cultural differences, including land-use practices, are critical in building trust and in how conflict transformation processes moved forward. Moreover, the ability of the mediator in facilitating the establishment of a deliberative institution (i.e. a watershed network committee and agreed rules on forest utilization were also critical in maintaining long-term collaboration in the watershed and potentially preventing other conflicts arising in the future. Some issues, however, may threaten the continuity of the cooperation and sustainability of peace in the watershed, including the lack of structural reform that formally recognizes local people’s rights, insecure land tenure, and the absence of legal recognition for the watershed network committee as a legitimate mechanism for watershed decision making. The paper discusses these findings by comparing it with those from our previous studies in other locations (Cambodia, Indonesia and Western Thailand to strengthen the insights from Northern Thailand. Finally, the research puts forward some recommendations for reforms and to strengthen the use of effective

  17. Spatially-explicit modeling of multi-scale drivers of aboveground forest biomass and water yield in watersheds of the Southeastern United States.

    Science.gov (United States)

    Ajaz Ahmed, Mukhtar Ahmed; Abd-Elrahman, Amr; Escobedo, Francisco J; Cropper, Wendell P; Martin, Timothy A; Timilsina, Nilesh

    2017-09-01

    Understanding ecosystem processes and the influence of regional scale drivers can provide useful information for managing forest ecosystems. Examining more local scale drivers of forest biomass and water yield can also provide insights for identifying and better understanding the effects of climate change and management on forests. We used diverse multi-scale datasets, functional models and Geographically Weighted Regression (GWR) to model ecosystem processes at the watershed scale and to interpret the influence of ecological drivers across the Southeastern United States (SE US). Aboveground forest biomass (AGB) was determined from available geospatial datasets and water yield was estimated using the Water Supply and Stress Index (WaSSI) model at the watershed level. Our geostatistical model examined the spatial variation in these relationships between ecosystem processes, climate, biophysical, and forest management variables at the watershed level across the SE US. Ecological and management drivers at the watershed level were analyzed locally to identify whether drivers contribute positively or negatively to aboveground forest biomass and water yield ecosystem processes and thus identifying potential synergies and tradeoffs across the SE US region. Although AGB and water yield drivers varied geographically across the study area, they were generally significantly influenced by climate (rainfall and temperature), land-cover factor1 (Water and barren), land-cover factor2 (wetland and forest), organic matter content high, rock depth, available water content, stand age, elevation, and LAI drivers. These drivers were positively or negatively associated with biomass or water yield which significantly contributes to ecosystem interactions or tradeoff/synergies. Our study introduced a spatially-explicit modelling framework to analyze the effect of ecosystem drivers on forest ecosystem structure, function and provision of services. This integrated model approach facilitates

  18. An approach to study the effect of harvest and wildfire on watershed hydrology and sediment yield in a coast redwood forest

    Science.gov (United States)

    Christopher G. Surfleet; Arne Skaugset; Brian Dietterick

    2012-01-01

    The Little Creek watershed, within California State Polytechnic University’s Swanton Pacific Ranch, is the location of a paired and nested watershed study to investigate the watershed effects of coast redwood forest management. Streamflow, suspended sediment, and stream turbidity have been collected during storms at two locations on the North Fork Little Creek and at...

  19. Estimating greenhouse gas emissions at the soil-atmosphere interface in forested watersheds of the US Northeast.

    Science.gov (United States)

    Gomez, Joshua; Vidon, Philippe; Gross, Jordan; Beier, Colin; Caputo, Jesse; Mitchell, Myron

    2016-05-01

    Although anthropogenic emissions of greenhouse gases (GHG: CO2, CH4, N2O) are unequivocally tied to climate change, natural systems such as forests have the potential to affect GHG concentration in the atmosphere. Our study reports GHG emissions as CO2, CH4, N2O, and CO2eq fluxes across a range of landscape hydrogeomorphic classes (wetlands, riparian areas, lower hillslopes, upper hillslopes) in a forested watershed of the Northeastern USA and assesses the usability of the topographic wetness index (TWI) as a tool to identify distinct landscape geomorphic classes to aid in the development of GHG budgets at the soil atmosphere interface at the watershed scale. Wetlands were hot spots of GHG production (in CO2eq) in the landscape owing to large CH4 emission. However, on an areal basis, the lower hillslope class had the greatest influence on the net watershed CO2eq efflux, mainly because it encompassed the largest proportion of the study watershed (54 %) and had high CO2 fluxes relative to other land classes. On an annual basis, summer, fall, winter, and spring accounted for 40, 27, 9, and 24 % of total CO2eq emissions, respectively. When compared to other approaches (e.g., random or systematic sampling design), the TWI landscape classification method was successful in identifying dominant landscape hydrogeomorphic classes and offered the possibility of systematically accounting for small areas of the watershed (e.g., wetlands) that have a disproportionate effect on total GHG emissions. Overall, results indicate that soil CO2eq efflux in the Archer Creek Watershed may exceed C uptake by live trees under current conditions.

  20. Watershed condition [Chapter 4

    Science.gov (United States)

    Daniel G. Neary; Jonathan W. Long; Malchus B. Baker

    2012-01-01

    Managers of the Prescott National Forest are obliged to evaluate the conditions of watersheds under their jurisdiction in order to guide informed decisions concerning grazing allotments, forest and woodland management, restoration treatments, and other management initiatives. Watershed condition has been delineated by contrasts between “good” and “poor” conditions (...

  1. Nitrogen (N) dynamics in the mineral soil of a Central Appalachian hardwood forest during a quarter century of whole-watershed N additions

    Science.gov (United States)

    Frank S. ​Gilliam; Christopher A. Walter; Mary Beth Adams; William T. Peterjohn

    2018-01-01

    The structure and function of terrestrial ecosystemsare maintained by processes that vary with temporal and spatial scale. This study examined temporal and spatial patterns of net nitrogen (N) mineralization and nitrification in mineral soil of three watersheds at the Fernow Experimental Forest, WV: 2 untreated watersheds and 1 watershed receiving aerial applications...

  2. Controls and forecasts of nitrate yields in forested watersheds: A view over mainland Portugal.

    Science.gov (United States)

    Pacheco, F A L; Santos, R M B; Sanches Fernandes, L F; Pereira, M G; Cortes, R M V

    2015-12-15

    A study on nitrate yields was conducted in forested watersheds of mainland Portugal. The prime goal was to rank parameters in descending order of their contribution to the export of nitrate towards streams and lakes. To attain the goal, variables like soil loss, rainfall intensity, topography, soil type, forest composition and environmental disturbances such as hardwood harvesting or wildfires were organized in a conceptual yield model. Because some parameters were potentially collinear, a robust multivariate statistical technique was selected to execute the conceptual model and perform the aforementioned ranking, namely Partial Least Squares (PLS) regression. This technique was tested with a sample of 60 forested watersheds (>70% of forest occupation), being subject to a double-validation process to ensure prediction capability. According to final regression coefficients, soil erosion seems to regulate nitrate distribution across the basins, because soil loss and type, rainfall intensity and topography explained around 60% of nitrate yield variance. The major importance of erosion is followed by a moderate role of biochemical processes such as nitrification or nutrient uptake, which accounted for approximately 15% of nitrate yield variance. In this case, deciduous forests and scrubland seem to behave as net sinks of nitrate while coniferous and mixed forests seem to act dually, as net sources or sinks. The least important parameters are the environmental disturbances, explaining no more than 5% of nitrate yield variance. The results of PLS regression were coupled in a scenario analysis with measures designed to protect soil from erosion and surface water from eutrophication. These interventions are to be implemented until 2045, according to regional plans of forest management. Considering the key role of erosion in explaining nitrate dynamics across the catchments, it was not surprising to verify that soil protection measures may reduce nitrate yields by some 35

  3. Hydrological services and biodiversity conservation under forestation scenarios: comparing options to improve watershed management

    Science.gov (United States)

    Carvalho-Santos, Claudia; Nunes, João Pedro; Sousa-Silva, Rita; Gonçalves, João; Pradinho Honrado, João

    2015-04-01

    Humans rely on ecosystems for the provision of hydrological services, namely water supply and water damage mitigation, and promoting forests is a widely used management strategy for the provision of hydrological services. Therefore, it is important to model how forests will contribute for this provision, taking into account the environmental characteristics of each region, as well as the spatio-temporal patterns of societal demand. In addition, ensuring forest protection and the delivery of forest ecosystem services is one of the aims included in the European Union biodiversity strategy to 2020. On the other hand, forest management for hydrological services must consider possible trade-offs with other services provision, as well as with biodiversity conservation. Accurate modeling and mapping of both hydrological services and biodiversity conservation value is thus important to support spatial planning and land management options involving forests. The objectives of this study were: to analyze the provision and spatial dynamics of hydrological services under two forest cover change scenarios (oak and eucalyptus/pine) compared to the current shrubland-dominated landscape; and to evaluate their spatial trade-offs with biodiversity conservation value. The Vez watershed (250km2), in northwest Portugal, was used as case-study area. SWAT (Soil and Water Assessment Tool) was applied to simulate the provision of hydrological services (water supply quantity, timing and quality; soil erosion and flood regulation), and was calibrated against daily discharge, sediments, nitrates and evapotranspiration. Good agreement was obtained between model predictions and field measurements. The maps for each service under the different scenarios were produced at the Hydrologic Response Unit (HRU) level. Biodiversity conservation value was based on nature protection regimes and on expert valuation applied to a land cover map. Statistical correlations between hydrological services provision

  4. Forest Ecosystem Processes at the Watershed Scale: Ecosystem services, feedback and evolution in developing mountainous catchments

    Science.gov (United States)

    Band, Larry

    2010-05-01

    Mountain watersheds provide significant ecosystem services both locally and for surrounding regions, including the provision of freshwater, hydropower, carbon sequestration, habitat, forest products and recreational/aesthetic opportunities. The hydrologic connectivity along hillslopes in sloping terrain provides an upslope subsidy of water and nutrients to downslope ecosystem patches, producing characteristic ecosystem patterns of vegetation density and type, and soil biogeochemical cycling. Recent work suggests that optimal patterns of forest cover evolve along these flowpaths which maximize net primary productivity and carbon sequestration at the hillslope to catchment scale. These watersheds are under significant pressure from potential climate change, changes in forest management, increasing population and development, and increasing demand for water export. As water balance and flowpaths are altered by shifting weather patterns and new development, the spatial distribution and coupling of water, carbon and nutrient cycling will spur the evolution of different ecosystem patterns. These issues have both theoretical and practical implications for the coupling of water, carbon and nutrient cycling at the landscape level, and the potential to manage watersheds for bundled ecosystem services. If the spatial structure of the ecosystem spontaneously adjusts to maximize landscape level use of limiting resources, there may be trade-offs in the level of services provided. The well known carbon-for-water tradeoff reflects the growth of forests to maximize carbon uptake, but also transpiration which limits freshwater availability in many biomes. We provide examples of the response of bundled ecosystem services to climate and land use change in the Southern Appalachian Mountains of the United States. These mountains have very high net primary productivity, biodiversity and water yields, and provide significant freshwater resources to surrounding regions. There has been a

  5. Hurricane impacts on a pair of coastal forested watersheds: implications of selective hurricane damage to forest structure and streamflow dynamics

    Science.gov (United States)

    A.D. Jayakaran; T.M. Williams; H. Ssegane; D.M. Amatya; B. Song; C.C. Trettin

    2014-01-01

    Hurricanes are infrequent but influential disruptors of ecosystem processes in the southeastern Atlantic and Gulf coasts. Every southeastern forested wetland has the potential to be struck by a tropical cyclone. We examined the impact of Hurricane Hugo on two paired coastal South Carolina watersheds in terms of streamflow and vegetation dynamics, both before and after...

  6. Assessing Watershed-Wildfire Risks on National Forest System Lands in the Rocky Mountain Region of the United States

    Directory of Open Access Journals (Sweden)

    Jessica R. Haas

    2013-07-01

    Full Text Available Wildfires can cause significant negative impacts to water quality with resultant consequences for the environment and human health and safety, as well as incurring substantial rehabilitation and water treatment costs. In this paper we will illustrate how state-of-the-art wildfire simulation modeling and geospatial risk assessment methods can be brought to bear to identify and prioritize at-risk watersheds for risk mitigation treatments, in both pre-fire and post-fire planning contexts. Risk assessment results can be particularly useful for prioritizing management of hazardous fuels to lessen the severity and likely impacts of future wildfires, where budgetary and other constraints limit the amount of area that can be treated. Specifically we generate spatially resolved estimates of wildfire likelihood and intensity, and couple that information with spatial data on watershed location and watershed erosion potential to quantify watershed exposure and risk. For a case study location we focus on National Forest System lands in the Rocky Mountain Region of the United States. The Region houses numerous watersheds that are critically important to drinking water supplies and that have been impacted or threatened by large wildfires in recent years. Assessment results are the culmination of a broader multi-year science-management partnership intended to have direct bearing on wildfire management decision processes in the Region. Our results suggest substantial variation in the exposure of and likely effects to highly valued watersheds throughout the Region, which carry significant implications for prioritization. In particular we identified the San Juan National Forest as having the highest concentration of at-risk highly valued watersheds, as well as the greatest amount of risk that can be mitigated via hazardous fuel reduction treatments. To conclude we describe future opportunities and challenges for management of wildfire-watershed interactions.

  7. Evaluation of hydrologic equilibrium in a mountainous watershed: incorporating forest canopy spatial adjustment to soil biogeochemical processes

    Science.gov (United States)

    Mackay, D. Scott

    Hydrologic equilibrium theory has been used to describe both short-term regulation of gas exchange and long-term adjustment of forest canopy density. However, by focusing on water and atmospheric conditions alone a hydrologic equilibrium may impose an oversimplification of the growth of forests adjusted to hydrology. In this study nitrogen is incorporated as a third regulation of catchment level forest dynamics and gas exchange. This was examined with an integrated distributed hydrology and forest growth model in a central Sierra Nevada watershed covered primarily by old-growth coniferous forest. Water and atmospheric conditions reasonably reproduced daily latent heat flux, and predicted the expected catenary trend of leaf area index (LAI). However, it was not until the model was provided a spatially detailed description of initial soil carbon and nitrogen pools that spatial patterns of LAI were generated. This latter problem was attributed to a lack of soil history or memory in the initialization of the simulations. Finally, by reducing stomatal sensitivity to vapor pressure deficit (VPD) the canopy density increased when water and nitrogen limitations were not present. The results support a three-control hydrologic equilibrium in the Sierra Nevada watershed. This has implications for modeling catchment level soil-vegetation-atmospheric interactions over interannual, decade, and century time-scales.

  8. Landslides and sediment budgets in four watersheds in eastern Puerto Rico: Chapter F in Water quality and landscape processes of four watersheds in eastern Puerto Rico

    Science.gov (United States)

    Larsen, Matthew C.; Murphy, Sheila F.; Stallard, Robert F.

    2012-01-01

    The low-latitude regions of the Earth are undergoing profound, rapid landscape change as forests are converted to agriculture to support growing population. Understanding the effects of these land-use changes requires analysis of watershed-scale geomorphic processes to better inform and manage this usually disorganized process. The investigation of hillslope erosion and the development of sediment budgets provides essential information for resource managers. Four small, montane, humid-tropical watersheds in the Luquillo Experimental Forest and nearby Río Grande de Loíza watershed, Puerto Rico (18° 20' N., 65° 45' W.), were selected to compare and contrast the geomorphic effects of land use and bedrock geology. Two of the watersheds are underlain largely by resistant Cretaceous volcaniclastic rocks but differ in land use and mean annual runoff: the Mameyes watershed, with predominantly primary forest cover and runoff of 2,750 millimeters per year, and the Canóvanas watershed, with mixed secondary forest and pasture and runoff of 970 millimeters per year. The additional two watersheds are underlain by relatively erodible granitic bedrock: the forested Icacos watershed, with runoff of 3,760 millimeters per year and the agriculturally developed Cayaguás watershed, with a mean annual runoff of 1,620 millimeters per year. Annual sediment budgets were estimated for each watershed using landslide, slopewash, soil creep, treethrow, suspended sediment, and streamflow data. The budgets also included estimates of sediment storage in channel beds, bars, floodplains, and in colluvial deposits. In the two watersheds underlain by volcaniclastic rocks, the forested Mameyes and the developed Canóvanas watersheds, landslide frequency (0.21 and 0.04 landslides per square kilometer per year, respectively), slopewash (5 and 30 metric tons per square kilometer per year), and suspended sediment yield (325 and 424 metric tons per square kilometer per year), were lower than in the

  9. A watershed-based environmental and regulatory data analysis system for the forest products industry

    Science.gov (United States)

    John Beebe

    2012-01-01

    A watershed-based data analysis system was created as a tool for forest product companies to better understand potential implications from environmental regulations. Also known as the Receiving Water Database (RWDB), this data system was designed with the purpose of assisting companies that own pulp and paper mills, wood product facilities, and commercial timberlands...

  10. Comparison of mineral weathering and biomass nutrient uptake in two small forested watersheds underlain by quartzite bedrock, Catoctin Mountain, Maryland, USA

    Science.gov (United States)

    Rice, Karen; Price, Jason R.

    2014-01-01

    To quantify chemical weathering and biological uptake, mass-balance calculations were performed on two small forested watersheds located in the Blue Ridge Physiographic Province in north-central Maryland, USA. Both watersheds, Bear Branch (BB) and Fishing Creek Tributary (FCT), are underlain by relatively unreactive quartzite bedrock. Such unreactive bedrock and associated low chemical-weathering rates offer the opportunity to quantify biological processes operating within the watershed. Hydrologic and stream-water chemistry data were collected from the two watersheds for the 9-year period from June 1, 1990 to May 31, 1999. Of the two watersheds, FCT exhibited both higher chemical-weathering rates and biomass nutrient uptake rates, suggesting that forest biomass aggradation was limited by the rate of chemical weathering of the bedrock. Although the chemical-weathering rate in the FCT watershed was low relative to the global average, it masked the influence of biomass base-cation uptake on stream-water chemistry. Any differences in bedrock mineralogy between the two watersheds did not exert a significant influence on the overall weathering stoichiometry. The difference in chemical-weathering rates between the two watersheds is best explained by a larger proportion of reactive phyllitic layers within the bedrock of the FCT watershed. Although the stream gradient of BB is about two-times greater than that of FCT, its influence on chemical weathering appears to be negligible. The findings of this study support the biomass nutrient uptake stoichiometry of K1.0Mg1.1Ca0.97 previously determined for the study site. Investigations of the chemical weathering of relatively unreactive quartzite bedrock may provide insight into critical zone processes.

  11. Bi-criteria evaluation of the MIKE SHE model for a forested watershed on the South Carolina coastal plain

    Directory of Open Access Journals (Sweden)

    Z. Dai

    2010-06-01

    Full Text Available Hydrological models are important tools for effective management, conservation and restoration of forested wetlands. The objective of this study was to test a distributed hydrological model, MIKE SHE, by using bi-criteria (i.e., two measurable variables, streamflow and water table depth to describe the hydrological processes in a forested watershed that is characteristic of the lower Atlantic Coastal Plain. Simulations were compared against observations of both streamflow and water table depth measured on a first-order watershed (WS80 on the Santee Experimental Forest in South Carolina, USA. Model performance was evaluated using coefficient of determination (R2 and Nash-Sutcliffe's model efficiency (E. The E and root mean squared error (RMSE were chosen as objective functions for sensitivity analysis of parameters. The model calibration and validation results demonstrated that the streamflow and water table depth were sensitive to most of the model input parameters, especially to surface detention storage, drainage depth, soil hydraulic properties, plant rooting depth, and surface roughness. Furthermore, the bi-criteria approach used for distributed model calibration and validation was shown to be better than the single-criterion in obtaining optimum model input parameters, especially for those parameters that were only sensitive to some specific conditions. Model calibration using the bi-criteria approach should be advantageous for constructing the uncertainty bounds of model inputs to simulate the hydrology for this type of forested watersheds. R2 varied from 0.60–0.99 for daily and monthly streamflow, and from 0.52–0.91 for daily water table depth. E changed from 0.53–0.96 for calibration and 0.51–0.98 for validation of daily and monthly streamflow, while E varied from 0.50–0.90 for calibration and 0.66–0.80 for validation of daily water table depth. This study showed

  12. Simulation Tools for Forest Health Analysis: An Application in the Red River Watershed, Idaho

    Science.gov (United States)

    Andrew J. McMahan; Eric L. Smith

    2006-01-01

    Software tools for landscape analyses--including FVS model extensions, and a number of FVS-related pre- and post-processing “tools”--are presented, using an analysis in the Red River Watershed, Nez Perce National Forest as an example. We present (1) a discussion of pre-simulation data analysis; (2) the Physiographic Information Extraction System (PIES), a tool that can...

  13. Timber markets and marketing in the Monocacy River watershed of Maryland and Pennsylvania

    Science.gov (United States)

    George E. Doverspike; James C. Rettie; Harry W., Jr. Camp

    1951-01-01

    The Maryland Department of State Forests and Parks, cooperating with the locally organized Monocacy River Watershed Council, has requested the Northeastern Forest Experiment Station to undertake a study of the forest resource of that watershed. The objective is to provide information that will be helpful in conserving watershed values and in promoting better management...

  14. Characterisation of diffuse pollutions from forested watersheds in Japan during storm events - its association with rainfall and watershed features.

    Science.gov (United States)

    Zhang, Zhao; Fukushima, Takehiko; Onda, Yuichi; Mizugaki, Shigeru; Gomi, Takashi; Kosugi, Ken'ichirou; Hiramatsu, Shinya; Kitahara, Hikaru; Kuraji, Koichiro; Terajima, Tomomi; Matsushige, Kazuo; Tao, Fulu

    2008-02-01

    Forest areas have been identified as important sources of nonpoint pollution in Japan. The managers must estimate stormwater quality and quantities from forested watersheds to develop effective management strategies. Therefore, stormwater runoff loads and concentrations of 10 constituents (total suspended solids, dissolved organic carbon, PO(4)-P, dissolved total phosphorus, total phosphorus, NH(4)-N, NO(2)-N, NO(3)-N, dissolved total nitrogen, and total nitrogen) for 72 events across five regions (Aichi, Kochi, Mie, Nagano, and Tokyo) were characterised. Most loads were significantly and positively correlated with stormwater variables (total event rainfall, event duration, and rainfall intensity), but most discharge-weighted event concentrations (DWECs) showed negative correlations with rainfall intensity. Mean water quality concentration during baseflow was correlated significantly with storm concentrations (r=0.41-0.77). Although all pollutant load equations showed high coefficients of determination (R(2)=0.55-0.80), no models predicted well pollutant concentrations, except those for the three N constituents (R(2)=0.59-0.67). Linear regressions to estimate stormwater concentrations and loads were greatly improved by regional grouping. The lower prediction capability of the concentration models for Mie, compared with the other four regions, indicated that other watershed or storm characteristics should be included in the prediction models. Significant differences among regions were found more frequently in concentrations than in loads for all constituents. Since baseflow conditions implied available pollutant sources for stormwater, the similar spatial characteristics of pollutant concentrations between baseflow and stormflow conditions were an important control for stormwater quality.

  15. [Impacts of forest and precipitation on runoff and sediment in Tianshui watershed and GM models].

    Science.gov (United States)

    Ouyang, H

    2000-12-01

    This paper analyzed the impacts of foret stand volume and precipitation on annual erosion modulus, mean sediment, maximum sediment, mean runoff, maximum runoff, minimum runoff, mean water level, maximum water level and minimum water level in Tianshui watershed, and also analyzed the effect of the variation of forest stand volume on monthly mean runoff, minimum runoff and mean water level. The dynamic models of grey system GM(1, N) were constructed to simulate the changes of these hydrological elements. The dynamic GM models on the impact of stand volumes of different forest types(Chinese fir, masson pine and broad-leaved forests) with different age classes(young, middle-aged, mature and over-mature) and that of precipitation on the hydrological elements were also constructed, and their changes with time were analyzed.

  16. Impact of wildfire on levels of mercury in forested watershed systems - Voyageurs National Park, Minnesota

    Science.gov (United States)

    Woodruff, Laurel G.; Sandheinrich, Mark B.; Brigham, Mark E.; Cannon, William F.

    2009-01-01

    Atmospheric deposition of mercury to remote lakes in mid-continental and eastern North America has increased approximately threefold since the mid-1800s (Swain and others, 1992; Fitzgerald and others, 1998; Engstrom and others, 2007). As a result, concerns for human and wildlife health related to mercury contamination have become widespread. Despite an apparent recent decline in atmospheric deposition of mercury in many areas of the Upper Midwest (Engstrom and Swain, 1997; Engstrom and others, 2007), lakes in which fish contain levels of mercury deemed unacceptable for human consumption and possibly unacceptable for fish-consuming wildlife are being detected with increasing frequency. In northern Minnesota, Voyageurs National Park (VNP) (fig. 1) protects a series of southern boreal lakes and wetlands situated on bedrock of the Precambrian Canadian Shield. Mercury contamination has become a significant resource issue within VNP as high concentrations of mercury in loons, bald eagle eaglets, grebes, northern pike, and other species of wildlife and fish have been found. The two most mercury-contaminated lakes in Minnesota, measured as methylmercury in northern pike (Esox lucius), are in VNP. Recent multidisciplinary U.S. Geological Survey (USGS) research demonstrated that the bulk of the mercury in lake waters, soils, and fish in VNP results from atmospheric deposition (Wiener and others, 2006). The study by Wiener and others (2006) showed that the spatial distribution of mercury in watershed soils, lake waters, and age-1 yellow perch (Perca flavescens) within the Park was highly variable. The majority of factors correlated for this earlier study suggested that mercury concentrations in lake waters and age-1 yellow perch reflected the influence of ecosystem processes that affected within-lake microbial production and abundance of methylmercury (Wiener and others, 2006), while the distribution of mercury in watershed soils seemed to be partially dependent on forest

  17. Hurricane impacts on a pair of coastal forested watersheds: implications of selective hurricane damage to forest structure and streamflow dynamics

    OpenAIRE

    A. D. Jayakaran; T. M. Williams; H. Ssegane; D. M. Amatya; B. Song; C. C. Trettin

    2014-01-01

    Hurricanes are infrequent but influential disruptors of ecosystem processes in the southeastern Atlantic and Gulf coasts. Every southeastern forested wetland has the potential to be struck by a tropical cyclone. We examined the impact of Hurricane Hugo on two paired coastal watersheds in South Carolina in terms of stream flow and vegetation dynamics, both before and after the hurricane's passage in 1989. The study objectives were to quantify the magnitude and timing of changes including a rev...

  18. Understanding the Hydrologic Response of a Coastal Plain Watershed to Forest Management and Climate Change in South Carolina, U.S.A.

    Science.gov (United States)

    J. Lu; Ge Sun; Devendra M. Amatya; S. V. Harder; Steve G. McNulty

    2006-01-01

    The hydrologic processes in wetland ecosystems are not well understood. There are also great concerns and uncertainties about the hydrologic response of wetlands to forest management and climate change. The objective of this study is to apply a hydrologic model to better understand the hydrologic processes of a low relief coastal forested watershed and its responses to...

  19. Characterizing Storm Event Dynamics of a Forested Watershed in the Lower Atlantic Coastal Plain, South Carolina USA

    Science.gov (United States)

    Latorre Torres, I. B.; Amatya, D. M.; Callahan, T. J.; Levine, N. S.

    2007-12-01

    Hydrology research in the Southeast U.S. has primarily focused on upland mountainous areas; however, much less is known about hydrological processes in Lower Coastal Plain (LCP) watersheds. Such watersheds are difficult to characterize due to shallow water table conditions, low topographic gradient, complex surface- subsurface water interaction, and lack of detailed soil information. Although opportunities to conduct long term monitoring in relatively undeveloped watersheds are often limited, stream flow and rainfall in the Turkey Creek watershed (third-order watershed, about 7200 ha in the Francis Marion National Forest near Charleston, SC) have been monitored since 1964. In this study, event runoff-rainfall ratios have been determined for 51 storm events using historical data from 1964-1973. One of our objectives was to characterize relationships between seasonal event rainfall and storm outflow in this watershed. To this end, observed storm event data were compared with values predicted by established hydrological methods such as the Soil Conservation Service runoff curve number (SCS-CN) and the rational method integrated within a Geographical Information System (GIS), to estimate total event runoff and peak discharge, respectively. Available 1:15000 scale aerial images were digitized to obtain land uses, which were used with the SCS soil hydrologic groups to obtain the runoff coefficients (C) for the rational method and the CN values for the SCS-CN method. These methods are being tested with historical storm event responses in the Turkey Creek watershed scale, and then will be used to predict event runoff in Quinby Creek, an ungauged third-order watershed (8700 ha) adjacent to Turkey Creek. Successful testing with refinement of parameters in the rational method and SCS-CN method, both designed for small urban and agricultural dominated watersheds, may allow widespread application of these methods for studying the event rainfall-runoff dynamics for similar

  20. Watershed restoration, jobs-in-the woods, and community assistance: Redwood National Park and the Northwest Forest Plan.

    Science.gov (United States)

    Christopher E. DeForest

    1999-01-01

    There are many parallels between the 1978 legislation to expand Redwood National Park and the Northwest Forest Plan, which together with the Northwest Economic Adjustment Initiative formed the 1993 Pacific Northwest Initiative. In both situations, the Federal Government sought to promote retraining for displaced workers, to undertake watershed assessment and...

  1. Application of the Precipitation Runoff Modeling System to measure impacts of forest fire on watershed hydrology

    Science.gov (United States)

    Driscoll, J. M.

    2015-12-01

    Precipitation in the southwestern United States falls primarily in areas of higher elevation. Drought conditions over the past five years have limited snowpack and rainfall, increasing the vulnerability to and frequency of forest fires in these montane regions. In June 2012, the Little Bear fire burned approximately 69 square miles (44,200 acres) in high-elevation forests of the Rio Hondo headwater catchments, south-central New Mexico. Burn severity was high or moderate on 53 percent of the burn area. The Precipitation Runoff Modeling System (PRMS) is a publically-available watershed model developed by the U.S. Geological Survey (USGS). PRMS data are spatially distributed using a 'Geospatial Fabric' developed at a national scale to define Hydrologic Response Units (HRUs), based on topography and points of interest (such as confluences and streamgages). The Little Bear PRMS study area is comprised of 22 HRUs over a 587 square-mile area contributing to the Rio Hondo above Chavez Canyon streamgage (USGS ID 08390020), in operation from 2008 to 2014. Model input data include spatially-distributed climate data from the National Aeronautics and Space Administration (NASA) DayMet and land cover (such as vegetation and soil properties) data from the USGS Geo Data Portal. Remote sensing of vegetation over time has provided a spatial distribution of recovery and has been applied using dynamic parameters within PRMS on the daily timestep over the study area. Investigation into the source and timing of water budget components in the Rio Hondo watershed may assist water planners and managers in determining how the surface-water and groundwater systems will react to future land use/land cover changes. Further application of PRMS in additional areas will allow for comparison of streamflow before and following wildfire conditions, and may lead to better understanding of the changes in watershed-scale hydrologic processes in the Southwest through post-fire watershed recovery.

  2. 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

  3. Effect to groundwater recharge caused by land use change, comparative filed observation in forest and grassland watersheds, Southwestern Japan

    Science.gov (United States)

    Kudo, K.; Shimada, J.; Tanaka, N.

    2011-12-01

    City of Kumamoto and their surrounding area are totally supported by the local groundwater as their tap water source, which is quite unique as comparing to the other large cities in Japan because Japanese large cities are mostly supplied by the surface water which is relatively easy to access for their tap water. Because of this, prefecture government of the Kumamoto City has much concern about the sustainable use of groundwater resources for their future generations. In Japan, for the sustainable use of groundwater resources, the forestation in the groundwater recharge area believed to increase the groundwater recharge to the local groundwater aquifer. It is true that the forestation surely works to reduce the direct runoff rate during the flooding period and also works to maintain a bit higher base flow rate during the low flow period than without forestation. However, the effect to the groundwater recharge rate by the forestation is not well understood because of the increase of evapo-transpiration by the tree itself. In order to understand the change of the groundwater recharge rate by the forestation, a paired catchments field observation has been conducted in two adjacent forest (0.088km2) and grassland (0.14km2) watersheds at the western foot of Mt. Aso known as recharge area of major local aquifer of Kumamoto region. The study sites are located at 32°53'N, 130°57'E with elevation ranging from 500 to 800m. The forest watershed consists mainly of around 30 year aged Japanese cypress plantations surrounded by Japanese cedar and mixture forest. The grassland watershed consists mainly of pasture and Japanese silver grass. Both catchments develop on the mountain foot slope consists of the Aso-2 pyroclastic sediments. As for the hydrometric observation system for each catchments, parshall flume runoff weir for the river discharge, meteoric tower for the evapo-transpiration monitoring purpose, and precipitation gage are installed to calculate groundwater recharge

  4. Sustainable forest management: a challenging task in the siran watershed of district Mansehra in the NWFP of Pakistan

    International Nuclear Information System (INIS)

    Khurshid, M.

    2005-01-01

    Forests play an important socio-economic and environmental role on earth. Exploitation of forest resources within the carrying capacity of the natural ecosystem has always ensured their sustainability but in recent decades man has overexploited these resources to meet various needs. Pakistan with only 4.8% of its total land area under forests was also experiencing unsustainable forest management. In the Siran Watershed of District Mansehra in the North West Frontier Province (NWFP) of Pakistan, forests were exploited to meet not only the domestic and commercial wood-fuel needs but also timber needs of the local and external markets. Moreover, the local communities as a source of income generation have also used forest resources to increase their cash income earnings. Analysis of time series forest cover change in the past three decades was done in three adjacent sub-watersheds having different property right regimes. The GIS based spatial analysis showed that despite government efforts to conserve these forests, 75% of the forests were completely converted either into regeneration area (34%) or barren areas (41 %) during the past three decades. The Protected Forests have lost 41 % of its cover and the Guzara Forests 34%. Results show that the forest degradation stress has greatly increased in the eighties and afterwards. Using stakeholder analysis the key wood demanding stake holders in terms of their wood demand state were the local communities, the external commercial timber consumers, tobacco growers and Afghan refugees. The wood supplies stake holders were the Forest Department that controls the Common Pool Forests (CPF), the Forest Development Corporation (FDC), the Forest Cooperative Societies (FCS) and the farm foresters. Analysis of the cause effect relationship of the system shows that the pressure factors of increased wood demand by various stake holders coupled with the enabling factors of the market failure, government failure and institutional failure

  5. Soil bacterial communities of a calcium-supplemented and a reference watershed at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA

    Science.gov (United States)

    Ganapathi Sridevi; Rakesh Minocha; Swathi A. Turlapati; Katherine C. Goldfarb; Eoin L. Brodie; Louis S. Tisa; Subhash C. Minocha

    2012-01-01

    Soil Ca depletion because of acidic deposition-related soil chemistry changes has led to the decline of forest productivity and carbon sequestration in the northeastern USA. In 1999, acidic watershed (WS) 1 at the Hubbard Brook Experimental Forest (HBEF), NH, USA was amended with Ca silicate to restore soil Ca pools. In 2006, soil samples were collected from the Ca-...

  6. Impacts of Sedimentation from Oil and Gas Development on Stream Macroinvertebrates in Two Adjacent Watersheds of the Allegheny National Forest of Northwestern Pennsylvania

    Energy Technology Data Exchange (ETDEWEB)

    Fritz, K.; Harris, S.; Edenborn, H.M.; Sams, J.

    2011-01-01

    Fritz, Kelley'*, Steven Harris', Harry Edenborn2, and James Sams2. 'Clarion University of Pennsylvania, Clarion, PA 16214, 2National Energy Technology Laboratory, U.S. Dept. Energy, Pittsburgh, PA 15236. Impacts a/Sedimentation/rom Oil and Gas Development on Stream Macroinvertebrates in Two Adjacent Watersheds a/the Allegheny National Forest a/Northwestern Pennsylvania - The Allegheny National Forest (ANF), located in northwestern Pennsy Ivania, is a multiuse forest combining commercial development with recreational and conservation activities. As such, portions of the ANF have been heavily logged and are now the subject of widespread oil and gas development. This rapid increase in oil and gas development has led to concerns about sediment runoff from the dirt and gravel roads associated with development and the potential impact on the aquatic biota of the receiving streams. We examined and compared the benthic macroinvertebrate communities in two adjacent watersheds of similar size and topography in the ANF; the Hedgehog Run watershed has no oil and gas development, while the adjacent Grunder Run watershed has extensive oil and gas development. In Hedgehog and Grunder Run, we collected monthly kicknet samples from riffles and glides at two sites from April to October 2010. At the same intervals, we measured standard water quality parameters, including conductivity and turbidity. Preliminary results have indicated much higher turbidity in Grunder Run, but little difference in the diversity and abundance of benthic macro invertebrates inhabiting the two streams.

  7. Watershed responses to Amazon soya bean cropland expansion and intensification.

    Science.gov (United States)

    Neill, Christopher; Coe, Michael T; Riskin, Shelby H; Krusche, Alex V; Elsenbeer, Helmut; Macedo, Marcia N; McHorney, Richard; Lefebvre, Paul; Davidson, Eric A; Scheffler, Raphael; Figueira, Adelaine Michela e Silva; Porder, Stephen; Deegan, Linda A

    2013-06-05

    The expansion and intensification of soya bean agriculture in southeastern Amazonia can alter watershed hydrology and biogeochemistry by changing the land cover, water balance and nutrient inputs. Several new insights on the responses of watershed hydrology and biogeochemistry to deforestation in Mato Grosso have emerged from recent intensive field campaigns in this region. Because of reduced evapotranspiration, total water export increases threefold to fourfold in soya bean watersheds compared with forest. However, the deep and highly permeable soils on the broad plateaus on which much of the soya bean cultivation has expanded buffer small soya bean watersheds against increased stormflows. Concentrations of nitrate and phosphate do not differ between forest or soya bean watersheds because fixation of phosphorus fertilizer by iron and aluminium oxides and anion exchange of nitrate in deep soils restrict nutrient movement. Despite resistance to biogeochemical change, streams in soya bean watersheds have higher temperatures caused by impoundments and reduction of bordering riparian forest. In larger rivers, increased water flow, current velocities and sediment flux following deforestation can reshape stream morphology, suggesting that cumulative impacts of deforestation in small watersheds will occur at larger scales.

  8. Sensitivity of stream flow and water table depth to potential climatic variability in a coastal forested watershed

    Science.gov (United States)

    Zhaohua Dai; Carl Trettin; Changsheng Li; Devendra M. Amatya; Ge Sun; Harbin Li

    2010-01-01

    A physically based distributed hydrological model, MIKE SHE, was used to evaluate the effects of altered temperature and precipitation regimes on the streamflow and water table in a forested watershed on the southeastern Atlantic coastal plain. The model calibration and validation against both streamflow and water table depth showed that the MIKE SHE was applicable for...

  9. Modeling the potential role of a forest ecosystem in phytostabilization and phytoextraction of 90Sr at a contaminated watershed

    International Nuclear Information System (INIS)

    Garten, C.T. Jr.

    1999-01-01

    The behavior of 90 Sr at forest sites in the White Oak Creek watershed, near Oak Ridge, Tennessee, was simulated with a simple, site-specific, multicompartment model that linked biomass and element cycling dynamics. The model was used to predict the role of forest cover in mitigating hydrologic losses of 90 Sr from contaminated soils (i.e. phytostabilization) under conditions where contaminant transport is governed mainly by shallow subsurface flow. The model was also used to predict the removal of 90 Sr from soil (i.e. phytoextraction) through the growth and harvest of short rotation woody crops over a period of 30 years. Simulations with the model indicated that (1) forest preservation on the watershed is a form of phytostabilization because forest cover helps to minimize hydrologic losses of 90 Sr and (2) an attempt to significantly reduce amounts of 90 Sr in soil through phytoextraction would be unsuccessful. Over a period of 30 years, and under various management strategies, the model predicted that 90 Sr initially present in soil at a contaminated site was lost through hydrologic transport and <53% was lost by radioactive decay. Phytostabilization may be important in the management of radioactive land when issues like waste minimization and pollution prevention affect the selection of technologies to be used in environmental restoration. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  10. 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...

  11. Divergent phenological response to hydroclimate variability in forested mountain watersheds.

    Science.gov (United States)

    Hwang, Taehee; Band, Lawrence E; Miniat, Chelcy F; Song, Conghe; Bolstad, Paul V; Vose, James M; Love, Jason P

    2014-08-01

    Mountain watersheds are primary sources of freshwater, carbon sequestration, and other ecosystem services. There is significant interest in the effects of climate change and variability on these processes over short to long time scales. Much of the impact of hydroclimate variability in forest ecosystems is manifested in vegetation dynamics in space and time. In steep terrain, leaf phenology responds to topoclimate in complex ways, and can produce specific and measurable shifts in landscape forest patterns. The onset of spring is usually delayed at a specific rate with increasing elevation (often called Hopkins' Law; Hopkins, 1918), reflecting the dominant controls of temperature on greenup timing. Contrary with greenup, leaf senescence shows inconsistent trends along elevation gradients. Here, we present mechanisms and an explanation for this variability and its significance for ecosystem patterns and services in response to climate. We use moderate-resolution imaging spectro-radiometer (MODIS) Normalized Difference Vegetation Index (NDVI) data to derive landscape-induced phenological patterns over topoclimate gradients in a humid temperate broadleaf forest in southern Appalachians. These phenological patterns are validated with different sets of field observations. Our data demonstrate that divergent behavior of leaf senescence with elevation is closely related to late growing season hydroclimate variability in temperature and water balance patterns. Specifically, a drier late growing season is associated with earlier leaf senescence at low elevation than at middle elevation. The effect of drought stress on vegetation senescence timing also leads to tighter coupling between growing season length and ecosystem water use estimated from observed precipitation and runoff generation. This study indicates increased late growing season drought may be leading to divergent ecosystem response between high and low elevation forests. Landscape-induced phenological patterns

  12. Institutional Development to Build a Succesfull Local Collective Action in Forest Management from Arau Watershed Unit

    Directory of Open Access Journals (Sweden)

    Nursidah Nursidah

    2012-04-01

    Full Text Available The study was aimed to build institution model of sustainable forest management, through analysis of action arena, community attributes and forest management rules in Arau Watershed Unit Management Area.  To achieve sustainable forest management, recognition and incorporation of local institutions in forest policy formulation is very important because it had great potential for collective action and had characteristics of common pools resources sustainable management needed.  To achieve a successful local collective action, the institution must be had: the rules in use suitable with local community norms; the organization has power to give reward and punishment as well as recognized and respected by society; specific management according location; rules of the game was made participatory; there are economic incentives for owners and users; there is an instrument for controlling sustainable use; and conflict resolution through negotiations to reach an concencus agreement.  The finding of institutional models  analysis  show  that  co-management  model  between government and local communities, called Nagari Forest Management Model is more suitable, because it gives greater opportunities for indigenous rights recognition to communal forest, until the capacity of villages get better, then the choice of forest management can be shifted into Nagari Community Based Forest Management Model.Keywords: sustainable forest management, institution, collective action, nagari

  13. Determining soil hydrologic characteristics on a remote forest watershed by continuous monitoring of soil water pressures, rainfall and runoff.

    Science.gov (United States)

    L.R. Ahuja; S. A. El-Swaify

    1979-01-01

    Continuous monitoring of soil-water pressures, rainfall and runoff under natural conditions was tested as a technique for determining soil hydrologic characteristics of a remote forest watershed plot. A completely battery-powered (and thus portable) pressure transducer–scanner–recorder system was assembled for monitoring of soil-water pressures in...

  14. Utilizing LiDAR Datasets From Experimental Watersheds to Advance Ecohydrological Understanding in Seasonally Snow-Covered Forests

    Science.gov (United States)

    Harpold, A. A.; Broxton, P. D.; Guo, Q.; Barlage, M. J.; Gochis, D. J.

    2014-12-01

    The Western U.S. is strongly reliant on snowmelt from forested areas for ecosystem services and downstream populations. The ability to manage water resources from snow-covered forests faces major challenges from drought, disturbance, and regional changes in climate. An exciting avenue for improving ecohydrological process understanding is Light Detection and Ranging (LiDAR) because the technology simultaneously observes topography, forest properties, and snow/ice at high-resolution (100 km2). The availability and quality of LiDAR datasets is increasing rapidly, however they remain under-utilized for process-based ecohydrology investigations. This presentation will illustrate how LiDAR datasets from the Critical Zone Observatory (CZO) network have been applied to advance ecohydrological understanding through direct empirical analysis, as well as model parameterization and verification. Direct analysis of the datasets has proved fruitful for pre- and post-disturbance snow distribution estimates and interpreting in-situ snow depth measurements across sites. In addition, we illustrate the potential value of LiDAR to parameterize and verify of physical models with two examples. First, we use LiDAR to parameterize a land surface model, Noah multi-parameterization (Noah-MP), to investigate the sensitivity of modeled water and energy fluxes to high-resolution forest information. Second, we present a Snow Physics and Laser Mapping (SnowPALM) model that is parameterized with LiDAR information at its native 1-m scale. Both modeling studies demonstrate the value of LiDAR for representing processes with greater fidelity. More importantly, the increased model fidelity led to different estimates of water and energy fluxes at larger, watershed scales. Creating a network of experimental watersheds with LiDAR datasets offers the potential to test theories and models in previously unexplored ways.

  15. Nitrate in watersheds: straight from soils to streams?

    Science.gov (United States)

    Sudduth, Elizabeth B.; Perakis, Steven S.; Bernhardt, Emily S.

    2013-01-01

    Human activities are rapidly increasing the global supply of reactive N and substantially altering the structure and hydrologic connectivity of managed ecosystems. There is long-standing recognition that N must be removed along hydrologic flowpaths from uplands to streams, yet it has proven difficult to assess the generality of this removal across ecosystem types, and whether these patterns are influenced by land-use change. To assess how well upland nitrate (NO3-) loss is reflected in stream export, we gathered information from >50 watershed biogeochemical studies that reported nitrate concentrations ([NO3-]) for stream water and for either upslope soil solution or groundwater NO3- to examine whether stream export of NO3- accurately reflects upland NO3- losses. In this dataset, soil solution and streamwater [NO3-] were correlated across 40 undisturbed forest watersheds, with streamwater [NO3-] typically half (median = 50%) soil solution [NO3-]. A similar relationship was seen in 10 disturbed forest watersheds. However, for 12 watersheds with significant agricultural or urban development, the intercept and slope were both significantly higher than the relationship seen in forest watersheds. Differences in concentration between soil solution or groundwater and stream water may be attributed to biological uptake, microbial processes including denitrification, and/or preferential flow routing. The results of this synthesis are consistent with the hypotheses that undisturbed watersheds have a significant capacity to remove nitrate after it passes below the rooting zone and that land use changes tend to alter the efficiency or the length of watershed flowpaths, leading to reductions in nitrate removal and increased stream nitrate concentrations.

  16. Historical effects of dissolved organic carbon export and land management decisions on the watershed-scale forest carbon budget of a coastal British Columbia Douglas-fir-dominated landscape

    Directory of Open Access Journals (Sweden)

    B. P. Smiley

    2017-07-01

    Full Text Available Abstract Background To address how natural disturbance, forest harvest, and deforestation from reservoir creation affect landscape-level carbon (C budgets, a retrospective C budget for the 8500 ha Sooke Lake Watershed (SLW from 1911 to 2012 was developed using historical spatial inventory and disturbance data. To simulate forest C dynamics, data was input into a spatially-explicit version of the Carbon Budget Model-Canadian Forest Sector (CBM-CFS3. Transfers of terrestrial C to inland aquatic environments need to be considered to better capture the watershed scale C balance. Using dissolved organic C (DOC and stream flow measurements from three SLW catchments, DOC load into the reservoir was derived for a 17-year period. C stocks and stock changes between a baseline and two alternative management scenarios were compared to understand the relative impact of successive reservoir expansions and sustained harvest activity over the 100-year period. Results Dissolved organic C flux for the three catchments ranged from 0.017 to 0.057 Mg C ha−1 year−1. Constraining CBM-CFS3 to observed DOC loads required parameterization of humified soil C losses of 2.5, 5.5, and 6.5%. Scaled to the watershed and assuming none of the exported terrestrial DOC was respired to CO2, we hypothesize that over 100 years up to 30,657 Mg C may have been available for sequestration in sediment. By 2012, deforestation due to reservoir creation/expansion resulted in the watershed forest lands sequestering 14 Mg C ha−1 less than without reservoir expansion. Sustained harvest activity had a substantially greater impact, reducing forest C stores by 93 Mg C ha−1 by 2012. However approximately half of the C exported as merchantable wood during logging (~176,000 Mg C may remain in harvested wood products, reducing the cumulative impact of forestry activity from 93 to 71 Mg C ha−1. Conclusions Dissolved organic C flux from temperate forest ecosystems is a

  17. Historical effects of dissolved organic carbon export and land management decisions on the watershed-scale forest carbon budget of a coastal British Columbia Douglas-fir-dominated landscape.

    Science.gov (United States)

    Smiley, B P; Trofymow, J A

    2017-12-01

    To address how natural disturbance, forest harvest, and deforestation from reservoir creation affect landscape-level carbon (C) budgets, a retrospective C budget for the 8500 ha Sooke Lake Watershed (SLW) from 1911 to 2012 was developed using historical spatial inventory and disturbance data. To simulate forest C dynamics, data was input into a spatially-explicit version of the Carbon Budget Model-Canadian Forest Sector (CBM-CFS3). Transfers of terrestrial C to inland aquatic environments need to be considered to better capture the watershed scale C balance. Using dissolved organic C (DOC) and stream flow measurements from three SLW catchments, DOC load into the reservoir was derived for a 17-year period. C stocks and stock changes between a baseline and two alternative management scenarios were compared to understand the relative impact of successive reservoir expansions and sustained harvest activity over the 100-year period. Dissolved organic C flux for the three catchments ranged from 0.017 to 0.057 Mg C ha -1  year -1 . Constraining CBM-CFS3 to observed DOC loads required parameterization of humified soil C losses of 2.5, 5.5, and 6.5%. Scaled to the watershed and assuming none of the exported terrestrial DOC was respired to CO 2 , we hypothesize that over 100 years up to 30,657 Mg C may have been available for sequestration in sediment. By 2012, deforestation due to reservoir creation/expansion resulted in the watershed forest lands sequestering 14 Mg C ha -1 less than without reservoir expansion. Sustained harvest activity had a substantially greater impact, reducing forest C stores by 93 Mg C ha -1 by 2012. However approximately half of the C exported as merchantable wood during logging (~176,000 Mg C) may remain in harvested wood products, reducing the cumulative impact of forestry activity from 93 to 71 Mg C ha -1 . Dissolved organic C flux from temperate forest ecosystems is a small but persistent C flux which may have long term

  18. 5. Basin assessment and watershed analysis

    Science.gov (United States)

    Leslie M. Reid; Robert R. Ziemer

    1994-01-01

    Abstract - Basin assessment is an important component of the President's Forest Plan, yet it has received little attention. Basin assessments are intended both to guide watershed analyses by specifying types of issues and interactions that need to be understood, and, eventually, to integrate the results of watershed analyses occurring within a river basin....

  19. Trends in Surface-Water Nitrate-N Concentrations and Loads from Predominantly-Forested Watersheds of the Chesapeake Bay Basin

    Science.gov (United States)

    Eshleman, K. N.

    2011-12-01

    Water quality monitoring data from streams and rivers provide the "gold standard" by which progress toward achieving real reductions in nutrient loadings to Chesapeake Bay must ultimately be assessed. The most recent trend results posted at the Chesapeake Bay Program (CBP) website reveal that a substantial percentage of tributaries are now showing long-term declines in flow-adjusted concentrations of nutrients and sediments: 22 sites showed statistically significant (p pollution controls for improved wastewater treatment plants and practices to reduce nutrients on farms and suburban lands, have reduced concentrations of nitrogen." But could this conclusion be pre-mature? I recently undertook a comparable analysis of long-term nitrate-N trends for a different group of watersheds (all located in the Chesapeake Bay watershed with long data records); this group includes nine watersheds that are predominantly (i.e., >75%) forested, plus five other Potomac River subwatersheds added for comparison. Based on comparable data and analytical methods to those used by CBP partners and USGS, 13 of the 14 sites-including both Potomac River stations (Chain Bridge at Washington DC and Hancock, Maryland)-showed statistically significant decreasing linear trends in annual flow-weighted nitrate-N concentration. Only one station-the heavily agricultural Upper Monocacy River-did not show a statistically significant (p RIM station could be entirely explained by commensurate improvements at the upstream (Hancock) station; in fact, no trend in nitrate-N concentration associated with the eastern portion of the basin was found (after subtracting out the influence of the upstream portion). Additional research is needed to understand why nitrogen retention by forested lands may be increasing and thus helping restore water quality throughout the Chesapeake Bay watershed. The results also have obvious implications for meeting local water quality goals as well as the basin-wide goal of the

  20. Valuation of Forest Resources in Watershed Areas: Selected Applications in Makiling Forest Reserve

    OpenAIRE

    Francisco, Herminia A.; Espiritu, Nena O.

    1999-01-01

    The valuation of resources found in the watershed area is important in assessing the impacts of changes in the watershed. While the change will have positive impacts which are short-term in nature, there are long-term environmental damages associated with economic benefits. This paper gives a rational judgment on the soundness of such changes through cost and benefit analysis. The watershed approach is utilized to capture the effects that are relevant in the analysis.

  1. Modeling of phosphorus fluxes produced by wild fires at watershed scales.

    Science.gov (United States)

    Matyjasik, M.; Hernandez, M.; Shaw, N.; Baker, M.; Fowles, M. T.; Cisney, T. A.; Jex, A. P.; Moisen, G.

    2017-12-01

    River runoff is one of the controlling processes in the terrestrial phosphorus cycle. Phosphorus is often a limiting factor in fresh water. One of the factors that has not been studied and modeled in detail is phosporus flux produced from forest wild fires. Phosphate released by weathering is quickly absorbed in soils. Forest wild fires expose barren soils to intensive erosion, thus releasing relatively large fluxes of phosphorus. Measurements from three control burn sites were used to correlate erosion with phosphorus fluxes. These results were used to model phosphorus fluxes from burned watersheds during a five year long period after fires occurred. Erosion in our model is simulated using a combination of two models: the WEPP (USDA Water Erosion Prediction Project) and the GeoWEPP (GIS-based Water Erosion Prediction Project). Erosion produced from forest disturbances is predicted for any watershed using hydrologic, soil, and meteorological data unique to the individual watersheds or individual slopes. The erosion results are modified for different textural soil classes and slope angles to model fluxes of phosphorus. The results of these models are calibrated using measured concentrations of phosphorus for three watersheds located in the Interior Western United States. The results will help the United States Forest Service manage phosporus fluxes in national forests.

  2. Chemistry and transport of soluble humic substances in forested watersheds of the Adirondack Park, New York

    Science.gov (United States)

    Cronan, C.S.; Aiken, G.R.

    1985-01-01

    Studies were conducted in conjunction with the Integrated Lake-Watershed Acidification Study (ILWAS) to examine the chemistry and leaching patterns of soluble humic substances in forested watersheds of the Adirondack region. During the summer growing season, mean dissolved organic carbon (DOC) concentrations in the ILWAS watersheds ranged from 21-32 mg C l-1 in O/A horizon leachates, from 5-7 mg C l-1 in B horizon leachates, from 2-4 mg C l-1 in groundwater solutions, from 6-8 mg C l-1 in first order streams, from 3-8 mg C l-1 in lake inlets, and from 2-7 mg C l-1 in lake outlets. During the winter, mean DOC concentrations dropped significantly in the upper soil profile. Soil solutions from mixed and coniferous stands contained as much as twice the DOC concentration of lysimeter samples from hardwood stands. Results of DOC fractionation analysis showed that hydrophobia and hydrophilic acids dominate the organic solute composition of natural waters in these watersheds. Charge balance and titration results indicated that the general acid-base characteristics of the dissolved humic mixture in these natural waters can be accounted for by a model organic acid having an averagepKa of 3.85, an average charge density of 4-5 ??eq mg-1 C at ambient pH, and a total of 6-7 meq COOH per gram carbon. ?? 1985.

  3. Characteristics of Sediment Transportation in Two Contrasting Oak Forested Watersheds in the Lesser Central Himalaya, India

    Science.gov (United States)

    Qazi, N. U. Q.; Bruijnzeel, S., Sr.; Rai, S. P., Sr.

    2015-12-01

    Sediment transfer from mountainous areas to lowland areas is one of the most important geomorphological processes globally with the bulk of the sediment yield from such areas typically deriving from mass wastage processes. This study presents monthly, seasonal and annual variations in sediment transport (both suspended load and bedload) as well as dissolved loads over three consecutive water years (2008-2011) for two small forested watersheds with contrasting levels of forest disturbance in the Lesser Himalaya of Northwest India. Seasonal and annual suspended sediment yields were strongly influenced by amounts of rainfall and streamflow and showed a 10-63 fold range between wet and dry years. Of the annual load, some 93% was produced on average during the monsoon season (June-September). Sediment production by the disturbed forest catchment was 1.9-fold (suspended sediment) to 5.9-fold (bedload) higher than that for the well-stocked forest catchment. By contrast, dissolved loads varied much less between years, seasons (although minimal during the dry summer season), and degree of forest disturbance. Total mechanical denudation rates were 1.6 times and 4.6 times larger than chemical denudation rates for the little disturbed and the heavily disturbed forest catchment, respectively whereas overall denudation rates were estimated at 0.69 and 1.04 mm per 1000 years, respectively.

  4. Guiding principles for management of forested, agricultural, and urban watersheds

    Science.gov (United States)

    Pamela J. Edwards; Jon E. Schoonover; Karl W.J. Williard

    2015-01-01

    Human actions must be well planned and include consideration of their potential influences on water and aquatic ecosystems - such consideration is the foundation of watershed management. Watersheds are the ideal land unit for managing and protecting water resources and aquatic health because watersheds integrate the physical, biological and chemical processes within...

  5. Estimation of different source contributions to sediment organic matter in an agricultural-forested watershed using end member mixing analyses based on stable isotope ratios and fluorescence spectroscopy.

    Science.gov (United States)

    Derrien, Morgane; Kim, Min-Seob; Ock, Giyoung; Hong, Seongjin; Cho, Jinwoo; Shin, Kyung-Hoon; Hur, Jin

    2018-03-15

    The two popular source tracing tools of stable isotope ratios (δ 13 C and δ 15 N) and fluorescence spectroscopy were used to estimate the relative source contributions to sediment organic matter (SeOM) at five different river sites in an agricultural-forested watershed (Soyang Lake watershed), and their capabilities for the source assignment were compared. Bulk sediments were used for the stable isotopes, while alkaline extractable organic matter (AEOM) from sediments was used to obtain fluorescent indices for SeOM. Several source discrimination indices were fully compiled for a range of the SeOM sources distributed in the catchments of the watershed, which included soils, forest leaves, crop (C3 and C4) and riparian plants, periphyton, and organic fertilizers. The relative source contributions to the river sediment samples were estimated via end member mixing analysis (EMMA) based on several selected discrimination indices. The EMMA based on the isotopes demonstrated that all sediments were characterized by a medium to a high contribution of periphyton ranging from ~30% to 70% except for one site heavily affected by forest and agricultural fields with relatively high contributions of terrestrial materials. The EMMA based on fluorescence parameters, however, did not show similar results with low contributions from forest leaf and periphyton. The characteristics of the studied watershed were more consistent with the source contributions determined by the isotope ratios. The discrepancy in the EMMA capability for source assignments between the two analytical tools can be explained by the limited analytical window of fluorescence spectroscopy for non-fluorescent dissolved organic matter (FDOM) and the inability of AEOM to represent original bulk particulate organic matter (POM). Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Applying soil property information for watershed assessment.

    Science.gov (United States)

    Archer, V.; Mayn, C.; Brown, S. R.

    2017-12-01

    The Forest Service uses a priority watershed scheme to guide where to direct watershed restoration work. Initial assessment was done across the nation following the watershed condition framework process. This assessment method uses soils information for a three step ranking across each 12 code hydrologic unit; however, the soil information used in the assessment may not provide adequate detail to guide work on the ground. Modern remote sensing information and terrain derivatives that model the environmental gradients hold promise of showing the influence of soil forming factors on watershed processes. These small scale data products enable the disaggregation of coarse scale soils mapping to show continuous soil property information across a watershed. When this information is coupled with the geomorphic and geologic information, watershed specialists can more aptly understand the controlling influences of drainage within watersheds and focus on where watershed restoration projects can have the most success. A case study on the application of this work shows where road restoration may be most effective.

  7. Use of ESI-FTICR-MS to Characterize Dissolved Organic Matter in Headwater Streams Draining Forest-Dominated and Pasture-Dominated Watersheds.

    Directory of Open Access Journals (Sweden)

    YueHan Lu

    Full Text Available Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI-FTICR-MS has proven to be a powerful technique revealing complexity and diversity of natural DOM molecules, but its application to DOM analysis in grazing-impacted agricultural systems remains scarce. In the present study, we presented a case study of using ESI-FTICR-MS in analyzing DOM from four headwater streams draining forest- or pasture-dominated watersheds in Virginia, USA. In all samples, most formulas were CHO compounds (71.8-87.9%, with other molecular series (CHOS, CHON, CHONS, and CHOP (N, S accounting for only minor fractions. All samples were dominated by molecules falling in the lignin-like region (H/C = 0.7-1.5, O/C = 0.1-0.67, suggesting the predominance of allochthonous, terrestrial plant-derived DOM. Relative to the two pasture streams, DOM formulas in the two forest streams were more similar, based on Jaccard similarity coefficients and nonmetric multidimensional scaling calculated from Bray-Curtis distance. Formulas from the pasture streams were characterized by lower proportions of aromatic formulas and lower unsaturation, suggesting that the allochthonous versus autochthonous contributions of organic matter to streams were modified by pasture land use. The number of condensed aromatic structures (CAS was higher for the forest streams, which is possibly due to the controlled burning in the forest-dominated watersheds and suggests that black carbon was mobilized from soils to streams. During 15-day biodegradation experiments, DOM from the two pasture streams was altered to a greater extent than DOM from the forest streams, with formulas with H/C and O/C ranges similar to protein (H/C = 1.5-2.2, O/C = 0.3-0.67, lipid (H/C = 1.5-2.0, O/C = 0-0.3, and unsaturated hydrocarbon (H/C = 0.7-1.5, O/C = 0-0.1 being the most bioreactive groups. Aromatic compound formulas including CAS were preferentially removed during combined light

  8. Exploring the Non-Stationary Effects of Forests and Developed Land within Watersheds on Biological Indicators of Streams Using Geographically-Weighted Regression

    Directory of Open Access Journals (Sweden)

    Kyoung-Jin An

    2016-03-01

    Full Text Available This study examined the non-stationary relationship between the ecological condition of streams and the proportions of forest and developed land in watersheds using geographically-weighted regression (GWR. Most previous studies have adopted the ordinary least squares (OLS method, which assumes stationarity of the relationship between land use and biological indicators. However, these conventional OLS models cannot provide any insight into local variations in the land use effects within watersheds. Here, we compared the performance of the OLS and GWR statistical models applied to benthic diatom, macroinvertebrate, and fish communities in sub-watershed management areas. We extracted land use datasets from the Ministry of Environment LULC map and data on biological indicators in Nakdong river systems from the National Aquatic Ecological Monitoring Program in Korea. We found that the GWR model had superior performance compared with the OLS model, as assessed based on R2, Akaike’s Information Criterion, and Moran’s I values. Furthermore, GWR models revealed specific localized effects of land use on biological indicators, which we investigated further. The results of this study can be used to inform more effective policies on watershed management and to enhance ecological integrity by prioritizing sub-watershed management areas

  9. Assessment of nitrate export from a high elevation watershed

    International Nuclear Information System (INIS)

    Williams, E.M.; Nodvin, S.C.

    1991-01-01

    Nitrate leaching from forest soils can be detrimental to both the forest ecosystems and stream water quality. Nitrate moving through the soil transports plant nutrients and acidifying agents, hydrogen and aluminum, and can export them to streams. In the high elevation spruce-fir forests in the Great Smoky Mountains National Park (GRSM) nitrate has been found to be leaching from the rooting zone. Streams associated with these ecosystems are poorly buffered. Therefore rapid export of nitrate from the soils to the streams could lead to episodic acidification. The purpose of the Noland Divide watershed study is to assess the levels of nitrate export from the watershed to the streams and the potential impacts of the export to the ecosystem

  10. Comparison of the Spatiotemporal Variability of Temperature, Precipitation, and Maximum Daily Spring Flows in Two Watersheds in Quebec Characterized by Different Land Use

    Directory of Open Access Journals (Sweden)

    Ali A. Assani

    2016-01-01

    Full Text Available We compared the spatiotemporal variability of temperatures and precipitation with that of the magnitude and timing of maximum daily spring flows in the geographically adjacent L’Assomption River (agricultural and Matawin River (forested watersheds during the period from 1932 to 2013. With regard to spatial variability, fall, winter, and spring temperatures as well as total precipitation are higher in the agricultural watershed than in the forested one. The magnitude of maximum daily spring flows is also higher in the first watershed as compared with the second, owing to substantial runoff, given that the amount of snow that gives rise to these flows is not significantly different in the two watersheds. These flows occur early in the season in the agricultural watershed because of the relatively high temperatures. With regard to temporal variability, minimum temperatures increased over time in both watersheds. Maximum temperatures in the fall only increased in the agricultural watershed. The amount of spring rain increased over time in both watersheds, whereas total precipitation increased significantly in the agricultural watershed only. However, the amount of snow decreased in the forested watershed. The magnitude of maximum daily spring flows increased over time in the forested watershed.

  11. What have we learned, and what is new in watershed science?

    Science.gov (United States)

    Robert R. Ziemer; Leslie M. Reid

    1997-01-01

    Abstract - Important new lessons are not in technical details, but in how to scale up the details to apply to large watersheds and landscapes. Nearly three years of experience with the Northwest Forest Plan have revealed some major new challenges in the fields of watershed science. In particular, managers and resource specialists engaged in watershed analysis...

  12. Disentangling the response of streamflow to forest management and climate

    Science.gov (United States)

    Dymond, S.; Miniat, C.; Bladon, K. D.; Keppeler, E.; Caldwell, P. V.

    2016-12-01

    Paired watershed studies have showcased the relationships between forests, management, and streamflow. However, classical analyses of paired-watershed studies have done little to disentangle the effects of management from overarching climatic signals, potentially masking the interaction between management and climate. Such approaches may confound our understanding of how forest management impacts streamflow. Here we use a 50-year record of streamflow and climate data from the Caspar Creek Experimental Watersheds (CCEW), California, USA to separate the effects of forest management and climate on streamflow. CCEW has two treatment watersheds that have been harvested in the past 50 years. We used a nonlinear mixed model to combine the pre-treatment relationship between streamflow and climate and the post-treatment relationship via an interaction between climate and management into one equation. Our results show that precipitation and potential evapotranspiration alone can account for >95% of the variability in pre-treatment streamflow. Including management scenarios into the model explained most of the variability in streamflow (R2 > 0.98). While forest harvesting altered streamflow in both of our modeled watersheds, removing 66% of the vegetation via selection logging using a tractor yarding system over the entire watershed had a more substantial impact on streamflow than clearcutting small portions of a watershed using cable-yarding. These results suggest that forest harvesting may result in differing impacts on streamflow and highlights the need to incorporate climate into streamflow analyses of paired-watershed studies.

  13. Decadal responses in soil N dynamics at the Bear Brook Watershed in Maine, USA

    Science.gov (United States)

    Sultana Jefts; Ivan J. Fernandez; Lindwey E. Rustad; D. Bryan Dail

    2004-01-01

    Atmospheric nitrogen deposition to forested ecosystems is a concern because of both geochemical and biological consequences for ecosystem integrity. High levels of prolonged N deposition can lead to "N saturation" of the ecosystem. The Bear Brook Watershed in Maine is a long-term, paired forested watershed experiment with over a decade of experimental N...

  14. Can Forest Transformation Help Reducing Floods in Forested Watersheds?

    DEFF Research Database (Denmark)

    Wahl, Niels Arne; Wöllecke, B.; Benz, O.

    2005-01-01

    of the management practice of forest transformation in forested areas on soil hydraulic properties is presented and discussed as a means of preventing such disasters at a reasonable cost and during a foreseeable period. Investigations were carried out in northeastern Germany on forest stands differing in tree...... populations and stand structure. It was found that infiltration capacity and hydraulic conductivity K exhibit overall low values nevertheless the tree species. This finding appears to be related to water repellency, the predominating texture, and a poor macroporosity. During the different stages of forest...

  15. Watershed manipulation project: Field implementation plan for 1990-1992

    International Nuclear Information System (INIS)

    Erickson, H.; Narahara, A.M.; Rustad, L.E.; Mitchell, M.; Lee, J.

    1993-02-01

    The Bear Brook Watershed in Maine (BBWM) was established in 1986 at Lead Mountain, Maine as part of the Environmental Protection Agency's (EPA) Watershed Manipulation Project (WPM). The goals of the project are to: (1) assess the chemical response of a small upland forested watershed to increased loadings of SO4, (2) determine interactions among biogeochemical mechanisms controlling watershed response to acidic deposition, and (3) test the assumptions of the Direct/Delayed Response Programs (DDRP) computer models of watershed acidification. The document summarizes the field procedures used in the establishment and initial implementation of the plot- and catchment- scale activities at the BBWM, and outlines plans for 1990-02 project activities

  16. Quantifying the hydrological responses to climate change in an intact forested small watershed in southern China

    Science.gov (United States)

    Zhou, Guo-Yi; Wei, Xiaohua; Wu, Yiping; Liu, Shu-Guang; Huang, Yuhui; Yan, Junhua; Zhang, Deqiang; Zhang, Qianmei; Liu, Juxiu; Meng, Ze; Wang, Chunlin; Chu, Guowei; Liu, Shizhong; Tang, Xu-Li; Liu, Xiaodong

    2011-01-01

    Responses of hydrological processes to climate change are key components in the Intergovernmental Panel for Climate Change (IPCC) assessment. Understanding these responses is critical for developing appropriate mitigation and adaptation strategies for sustainable water resources management and protection of public safety. However, these responses are not well understood and little long-term evidence exists. Herein, we show how climate change, specifically increased air temperature and storm intensity, can affect soil moisture dynamics and hydrological variables based on both long-term observation and model simulations using the Soil and Water Assessment Tool (SWAT) in an intact forested watershed (the Dinghushan Biosphere Reserve) in Southern China. Our results show that, although total annual precipitation changed little from 1950 to 2009, soil moisture decreased significantly. A significant decline was also found in the monthly 7-day low flow from 2000 to 2009. However, the maximum daily streamflow in the wet season and unconfined groundwater tables have significantly increased during the same 10-year period. The significant decreasing trends on soil moisture and low flow variables suggest that the study watershed is moving towards drought-like condition. Our analysis indicates that the intensification of rainfall storms and the increasing number of annual no-rain days were responsible for the increasing chance of both droughts and floods. We conclude that climate change has indeed induced more extreme hydrological events (e.g. droughts and floods) in this watershed and perhaps other areas of Southern China. This study also demonstrated usefulness of our research methodology and its possible applications on quantifying the impacts of climate change on hydrology in any other watersheds where long-term data are available and human disturbance is negligible.

  17. Uncertainty in future water supplies from forests: hydrologic effects of a changing forest landscape

    Science.gov (United States)

    Jones, J. A.; Achterman, G. L.; Alexander, L. E.; Brooks, K. N.; Creed, I. F.; Ffolliott, P. F.; MacDonald, L.; Wemple, B. C.

    2008-12-01

    Forests account for 33 percent of the U.S. land area, process nearly two-thirds of the fresh water supply, and provide water to 40 percent of all municipalities or about 180 million people. Water supply management is becoming more difficult given the increasing demand for water, climate change, increasing development, changing forest ownership, and increasingly fragmented laws governing forest and watershed management. In 2006, the US National Research Council convened a study on the present understanding of forest hydrology, the hydrologic effects of a changing forest landscape, and research and management needs for sustaining water resources from forested landscapes. The committee concluded that while it is possible to generate short-term water yield increases by timber harvesting, there are a variety of reasons why active forest management has only limited potential to sustainably increase water supplies. These include the short-term nature of the increases in most environments, the timing of the increases, the need for downstream storage, and that continuing ground- based timber harvest can reduce water quality. At the same time, past and continuing changes in forest structure and management may be altering water supplies at the larger time and space scales that are of most interest to forest and water managers. These changes include the legacy of past forest management practices, particularly fire suppression and clearcutting; exurban sprawl, which permanently converts forest land to nonforest uses; effects of climate change on wildfires, insect outbreaks, forest structure, forest species composition, snowpack depth and snowmelt; road networks; and changes in forest land ownership. All of these changes have the potential to alter water quantity and quality from forests. Hence, the baseline conditions that have been used to estimate sustained water yields from forested watersheds may no longer be applicable. Stationarity also can no longer be assumed for the

  18. Forests on the edge: housing development on America’s private forests.

    Science.gov (United States)

    Ronald E. McRoberts; Ralph J. Alig; Mark D. Nelson; David M. Theobald; Mike Eley; Mike Dechter; Mary. Carr

    2005-01-01

    The private working land base of America’s forests is being converted to developed uses, with implications for the condition and management of affected private forests and the watersheds in which they occur. The Forests on the Edge project seeks to improve understanding of the processes and thresholds associated with increases in housing density in private forests and...

  19. EXPERIMENTAL ACIDIFICATION CAUSES SOIL BASE-CATION DEPLETION AT THE BEAR BROOK WATERSHED IN MAINE

    Science.gov (United States)

    There is concern that changes in atmospheric deposition, climate, or land use have altered the biogeochemistry of forests causing soil base-cation depletion, particularly Ca. The Bear Brook Watershed in Maine (BBWM) is a paired watershed experiment with one watershed subjected to...

  20. Applying four principles of headwater system aquatic biology to forest management

    Science.gov (United States)

    Robert J. Danehy; Sherri L. Johnson

    2013-01-01

    Headwater systems, including the channel and the adjacent riparian forest, are a dominant landscape feature in forested watersheds, draining most of the watershed area, and comprising the majority of channel length in drainage networks. Being at the upper extent of watersheds, these systems are smaller and steeper than large streams, and create microhabitats that...

  1. Land Use-Land Cover dynamics of Huluka watershed, Central Rift Valley, Ethiopia

    Directory of Open Access Journals (Sweden)

    Hagos Gebreslassie

    2014-12-01

    Full Text Available Land Use-Land Cover (LULC dynamic has of human kind age and is one of the phenomenons which interweave the socio economic and environmental issues in Ethiopia. Huluka watershed is one of the watersheds in Central Rift Valley of Ethiopia which drains to Lake Langano. Few decades ago the stated watershed was covered with dense acacia forest. But, nowadays like other part of Ethiopia, it is experiencing complex dynamics of LULC. The aim of this research was thus to evaluate the LULC dynamics seen in between 1973–2009. This was achieved through collecting qualitative and quantitative data using Geographic Information System (GIS and Remote Sensing (RS technique. Field observations, discussion with elders were also employed to validate results from remotely sensed data. Based on the result, eight major dynamic LULC classes were identified from the watershed. Of these LULC classes, only cultivated and open lands had shown continuous and progressive expansion mainly at the expense of grass, shrub and forest lands. The 25% and 0% of cultivated and open land of the watershed in 1973 expanded to 84% and 4% in 2009 respectively while the 29%, 18% and 22% of grass, shrub and forest land of the watershed in 1973 degraded to 3.5%, 4% and 1.5% in 2009 respectively. As a result, land units which had been used for pastoralist before 1973 were identified under mixed agricultural system after 2000. In the end, this study came with a recommendation of an intervention of concerned body to stop the rapid degradation of vegetation on the watershed.

  2. Consistency of Hydrologic Relationships of a Paired Watershed Approach

    Science.gov (United States)

    Herbert Ssegane; Devendra M. Amatya; George M. Chescheir; Wayne R. Skaggs; Ernest W. Tollner; Jami E.. Nettles

    2013-01-01

    Paired watershed studies are used around the world to evaluate and quantify effects of forest and water management practices on hydrology and water quality. The basic concept uses two neighboring watersheds (one as a control and another as a treatment), which are concurrently monitored during calibration (pre-treatment) and post-treatment periods. A statistically...

  3. Mass-balance modeling of mineral weathering rates and CO2 consumption in the forested, metabasaltic Hauver Branch watershed, Catoctin Mountain, Maryland, USA

    Science.gov (United States)

    Rice, Karen; Price, Jason R.; Szymanski, David W.

    2013-01-01

    Mineral weathering rates and a forest macronutrient uptake stoichiometry were determined for the forested, metabasaltic Hauver Branch watershed in north-central Maryland, USA. Previous studies of Hauver Branch have had an insufficient number of analytes to permit determination of rates of all the minerals involved in chemical weathering, including biomass. More equations in the mass-balance matrix were added using existing mineralogic information. The stoichiometry of a deciduous biomass term was determined using multi-year weekly to biweekly stream-water chemistry for a nearby watershed, which drains relatively unreactive quartzite bedrock.At Hauver Branch, calcite hosts ~38 mol% of the calcium ion (Ca2+) contained in weathering minerals, but its weathering provides ~90% of the stream water Ca2+. This occurs in a landscape with a regolith residence time of more than several Ka (kiloannum). Previous studies indicate that such old regolith does not typically contain dissolving calcite that affects stream Ca2+/Na+ ratios. The relatively high calcite dissolution rate likely reflects dissolution of calcite in fractures of the deep critical zone.Of the carbon dioxide (CO2) consumed by mineral weathering, calcite is responsible for approximately 27%, with the silicate weathering consumption rate far exceeding that of the global average. The chemical weathering of mafic terrains in decaying orogens thus may be capable of influencing global geochemical cycles, and therefore, climate, on geological timescales. Based on carbon-balance calculations, atmospheric-derived sulfuric acid is responsible for approximately 22% of the mineral weathering occurring in the watershed. Our results suggest that rising air temperatures, driven by global warming and resulting in higher precipitation, will cause the rate of chemical weathering in the Hauver Branch watershed to increase until a threshold temperature is reached. Beyond the threshold temperature, increased recharge would

  4. Quantifying the hydrological responses to climate change in an intact forested small watershed in Southern China

    Science.gov (United States)

    Zhou, G.; Wei, X.; Wu, Y.; Huang, Y.; Yan, J.; Zhang, Dongxiao; Zhang, Q.; Liu, J.; Meng, Z.; Wang, C.; Chu, G.; Liu, S.; Tang, X.; Liu, Xiuying

    2011-01-01

    Responses of hydrological processes to climate change are key components in the Intergovernmental Panel for Climate Change (IPCC) assessment. Understanding these responses is critical for developing appropriate mitigation and adaptation strategies for sustainable water resources management and protection of public safety. However, these responses are not well understood and little long-term evidence exists. Herein, we show how climate change, specifically increased air temperature and storm intensity, can affect soil moisture dynamics and hydrological variables based on both long-term observation and model simulations using the Soil and Water Assessment Tool (SWAT) in an intact forested watershed (the Dinghushan Biosphere Reserve) in Southern China. Our results show that, although total annual precipitation changed little from 1950 to 2009, soil moisture decreased significantly. A significant decline was also found in the monthly 7-day low flow from 2000 to 2009. However, the maximum daily streamflow in the wet season and unconfined groundwater tables have significantly increased during the same 10-year period. The significant decreasing trends on soil moisture and low flow variables suggest that the study watershed is moving towards drought-like condition. Our analysis indicates that the intensification of rainfall storms and the increasing number of annual no-rain days were responsible for the increasing chance of both droughts and floods. We conclude that climate change has indeed induced more extreme hydrological events (e.g. droughts and floods) in this watershed and perhaps other areas of Southern China. This study also demonstrated usefulness of our research methodology and its possible applications on quantifying the impacts of climate change on hydrology in any other watersheds where long-term data are available and human disturbance is negligible. ?? 2011 Blackwell Publishing Ltd.

  5. Research related to roads in USDA experimental forests [Chapter 16

    Science.gov (United States)

    W. J. Elliot; P. J. Edwards; R. B. Foltz

    2014-01-01

    Forest roads are essential in experimental forests and rangelands (EFRs) to allow researchers and the public access to research sites and for fire suppression, timber extraction, and fuel management. Sediment from roads can adversely impact watershed health. Since the 1930s, the design and management of forest roads has addressed both access issues and watershed health...

  6. Contrasting residence times and fluxes of water and sulfate in two small forested watersheds in Virginia, USA.

    Science.gov (United States)

    Böhlke, John Karl; Michel, Robert L

    2009-07-01

    Watershed mass balances for solutes of atmospheric origin may be complicated by the residence times of water and solutes at various time scales. In two small forested headwater catchments in the Appalachian Mountains of Virginia, USA, mean annual export rates of SO(4)(=) differ by a factor of 2, and seasonal variations in SO(4)(=) concentrations in atmospheric deposition and stream water are out of phase. These features were investigated by comparing (3)H, (35)S, delta(34)S, delta(2)H, delta(18)O, delta(3)He, CFC-12, SF(6), and chemical analyses of open deposition, throughfall, stream water, and spring water. The concentrations of SO(4)(=) and radioactive (35)S were about twice as high in throughfall as in open deposition, but the weighted composite values of (35)S/S (11.1 and 12.1x10(-15)) and delta(34)S (+3.8 and +4.1 per thousand) were similar. In both streams (Shelter Run, Mill Run), (3)H concentrations and delta(34)S values during high flow were similar to those of modern deposition, delta(2)H and delta(18)O values exhibited damped seasonal variations, and (35)S/S ratios (0-3x10(-15)) were low throughout the year, indicating inter-seasonal to inter-annual storage and release of atmospheric SO(4)(=) in both watersheds. In the Mill Run watershed, (3)H concentrations in stream base flow (10-13 TU) were consistent with relatively young groundwater discharge, most delta(34)S values were approximately the same as the modern atmospheric deposition values, and the annual export rate of SO(4)(=) was equal to or slightly greater than the modern deposition rate. In the Shelter Run watershed, (3)H concentrations in stream base flow (1-3 TU) indicate that much of the discharging ground water had been deposited prior to the onset of atmospheric nuclear bomb testing in the 1950s, base flow delta(34)S values (+1.6 per thousand) were significantly lower than the modern deposition values, and the annual export rate of SO(4)(=) was less than the modern deposition rate

  7. Role of the USDA Forest Service experimental forest: an extension point of view

    Science.gov (United States)

    Eric L. Taylor; C. Darwin Foster; Diomy Zamora

    2013-01-01

    The expansive network of experimental forests (EF) facilitated by the U.S. Forest Service (Forest Service) encompasses a fairly complete representation of the forest ecotypes in the nation. The network, 101 years old this year (2009), has provided researchers with a wealth of long-term data on silviculture, watershed protection, and restoration. However, our nation’s...

  8. Watershed-scale evaluation of the Water Erosion Prediction Project (WEPP) model in the Lake Tahoe basin

    Science.gov (United States)

    Erin S. Brooks; Mariana Dobre; William J. Elliot; Joan Q. Wu; Jan Boll

    2016-01-01

    Forest managers need methods to evaluate the impacts of management at the watershed scale. The Water Erosion Prediction Project (WEPP) has the ability to model disturbed forested hillslopes, but has difficulty addressing some of the critical processes that are important at a watershed scale, including baseflow and water yield. In order to apply WEPP to...

  9. Comparative assessment of runoff characteristics under different land use patterns within a Himalayan watershed

    Science.gov (United States)

    Rai, S. C.; Sharma, E.

    1998-10-01

    Large quantities of sediments leave the Himalaya through its rivers. These rivers are charged with sediments depending on the types of land use in the watersheds. Land use/cover change and hydrology was studied in a watershed in the Sikkim Himalaya. The land use change from forest and agroforestry to open agriculture has increased by 11% from 1988 to 1992. During the same period substantial areas of dense mixed forests have been converted to open mixed and degraded forests as a result of high pressure on natural resources. Stream flow was highest in the rainy season and lowest in summer season in all the streams and all the three years (1994-1997) of the study. The water quality of streams from different microwatersheds varied significantly between seasons and streams. Sediment and nutrient loss was estimated in microwatersheds and soil loss from the total watershed ranged from 4·18 to 8·82 t ha-1 yr-1 during the three-year period of study. The annual total nitrogen loss estimated at the watershed outlet was at a rate of 33 kg ha-1, organic carbon 267 kg ha-1 and total phosphorus 5 kg ha-1. This study suggests that the upland microwatersheds can be hydroecologically sustainable only if good forest cover and dense forests with large cardamom-based agroforestry are maintained.

  10. Channel bed particle size distribution procedure used to evaluate watershed cumulative effects for range permit re-issuance on the Santa Fe National Forest

    Science.gov (United States)

    Bruce Sims; Jim Piatt; Lee Johnson; Carol Purchase; John Phillips

    1996-01-01

    Personnel on the Santa Fe National Forest used methodologies adapted from Bevenger and King (1995) to collect base line particle size data on streams within grazing allotments currently scheduled for permit reissuance. This information was used to determine the relative current health of the watersheds as well as being used in the development of potential alternatives...

  11. Forest Management Challenges for Sustaining Water Resources in the Anthropocene

    Directory of Open Access Journals (Sweden)

    Ge Sun

    2016-03-01

    Full Text Available The Earth has entered the Anthropocene epoch that is dominated by humans who demand unprecedented quantities of goods and services from forests. The science of forest hydrology and watershed management generated during the past century provides a basic understanding of relationships among forests and water and offers management principles that maximize the benefits of forests for people while sustaining watershed ecosystems. However, the rapid pace of changes in climate, disturbance regimes, invasive species, human population growth, and land use expected in the 21st century is likely to create substantial challenges for watershed management that may require new approaches, models, and best management practices. These challenges are likely to be complex and large scale, involving a combination of direct and indirect biophysical watershed responses, as well as socioeconomic impacts and feedbacks. We discuss the complex relationships between forests and water in a rapidly changing environment, examine the trade-offs and conflicts between water and other resources, and propose new management approaches for sustaining water resources in the Anthropocene.

  12. Watershed hydrology. Chapter 7.

    Science.gov (United States)

    Elons S. Verry; Kenneth N. Brooks; Dale S. Nichols; Dawn R. Ferris; Stephen D. Sebestyen

    2011-01-01

    Watershed hydrology is determined by the local climate, land use, and pathways of water flow. At the Marcell Experimental Forest (MEF), streamflow is dominated by spring runoff events driven by snowmelt and spring rains common to the strongly continental climate of northern Minnesota. Snowmelt and rainfall in early spring saturate both mineral and organic soils and...

  13. Large woody debris budgets in the Caspar Creek Experimental Watersheds

    Science.gov (United States)

    Sue Hilton

    2012-01-01

    Monitoring of large woody debris (LWD) in the two mainstem channels of the Caspar Creek Experimental Watersheds since 1998, combined with older data from other work in the watersheds, gives estimates of channel wood input rates, survival, and outputs in intermediate-sized channels in coastal redwood forests. Input rates from standing trees for the two reaches over a 15...

  14. Weathering, landscape equilibrium, and carbon in four watersheds in eastern Puerto Rico: Chapter H in Water quality and landscape processes of four watersheds in eastern Puerto Rico

    Science.gov (United States)

    Stallard, Robert F.; Murphy, Sheila F.; Stallard, Robert F.

    2012-01-01

    The U.S. Geological Survey's Water, Energy, and Biogeochemical Budgets (WEBB) program research in eastern Puerto Rico involves a double pair-wise comparison of four montane river basins, two on granitic bedrock and two on fine-grained volcaniclastic bedrock; for each rock type, one is forested and the other is developed. A confounding factor in this comparison is that the developed watersheds are substantially drier than the forested (runoff of 900–1,600 millimeters per year compared with 2,800–3,700 millimeters per year). To reduce the effects of contrasting runoff, the relation between annual runoff and annual constituent yield were used to estimate mean-annual yields at a common, intermediate mean-annual runoff of 1,860 millimeters per year. Upon projection to this intermediate runoff, the ranges of mean-annual yields among all watersheds became more compact or did not substantially change for dissolved bedrock, sodium, silica, chloride, dissolved organic carbon, and calcium. These constituents are the primary indicators of chemical weathering, biological activity on the landscape, and atmospheric inputs; the narrow ranges indicate little preferential influence by either geology or land cover. The projected yields of biologically active constituents (potassium, nitrate, ammonium ion, phosphate), and particulate constituents (suspended bedrock and particulate organic carbon) were considerably greater for developed landscapes compared with forested watersheds, consistent with the known effects of land clearing and human waste inputs. Equilibrium rates of combined chemical and physical weathering were estimated by using a method based on concentrations of silicon and sodium in bedrock, river-borne solids, and river-borne solutes. The observed rates of landscape denudation greatly exceed rates expected for a dynamic equilibrium, except possibly for the forested watershed on volcaniclastic rock. Deforestation and agriculture can explain the accelerated physical

  15. Telemetric system for hydrology and water quality monitoring in watersheds of northern New Mexico, USA.

    Science.gov (United States)

    Meyer, Michael L; Huey, Greg M

    2006-05-01

    This study utilized telemetric systems to sample microbes and pathogens in forest, burned forest, rangeland, and urban watersheds to assess surface water quality in northern New Mexico. Four sites included remote mountainous watersheds, prairie rangelands, and a small urban area. The telemetric system was linked to dataloggers with automated event monitoring equipment to monitor discharge, turbidity, electrical conductivity, water temperature, and rainfall during base flow and storm events. Site data stored in dataloggers was uploaded to one of three types of telemetry: 1) radio in rangeland and urban settings; 2) a conventional phone/modem system with a modem positioned at the urban/forest interface; and 3) a satellite system used in a remote mountainous burned forest watershed. The major variables affecting selection of each system were site access, distance, technology, and cost. The systems were compared based on operation and cost. Utilization of telecommunications systems in this varied geographic area facilitated the gathering of hydrologic and water quality data on a timely basis.

  16. Long-Term Soil Chemistry Changes in Aggrading Forest Ecosystems

    Science.gov (United States)

    Jennifer D. Knoepp; Wayne T. Swank

    1994-01-01

    Assessing potential long-term forest productivity requires identification of the processes regulating chemical changes in forest soils. We resampled the litter layer and upper two mineral soil horizons, A and AB/BA, in two aggrading southern Appalachian watersheds 20 yr after an earlier sampling. Soils from a mixed-hardwood watershed exhibited a small but significant...

  17. Mercury and Organic Carbon Relationships in Streams Draining Forested Upland/Peatland Watersheds

    Science.gov (United States)

    R. K. Kolka; D. F. Grigal; E. S. Verry; E. A. Nater

    1999-01-01

    We determined the fluxes of total mecury (HgT), total organic carbon (TOC), and dissolved organic carbon (DOC) from five upland/peatland watersheds at the watershed outlet. The difference between TOC and DOC was defined as particulate OC (POC). Concentrations of HgT showed moderate to strong relationships with POC (R2 = 0.77) when all watersheds...

  18. Experimental Acidification Causes Soil Base-Cation Depletion at the Bear Brook Watershed in Maine

    Science.gov (United States)

    Ivan J. Fernandez; Lindsey E. Rustad; Stephen A. Norton; Jeffrey S. Kahl; Bernard J. Cosby

    2003-01-01

    There is concern that changes in atmospheric deposition, climate, or land use have altered the biogeochemistry of forests causing soil base-cation depletion, particularly Ca. The Bear Brook Watershed in Maine (BBWM) is a paired watershed experiment with one watershed subjected to elevated N and S deposition through bimonthly additions of (NH4)2SO4. Quantitative soil...

  19. Forests on the edge: evaluating contributions of and threats to America's private forest lands

    Science.gov (United States)

    Mark Hatfield; Ronald E. McRoberts; Dacia M. Meneguzzo; Mike Dechter; < i> et al< /i>

    2007-01-01

    The Forests on the Edge project, sponsored by the U.S. Department of Agriculture Forest Service, uses geographic information systems to construct and analyze maps depicting ecological, social, and economic contributions of America's private forest lands and threats to those contributions. Watersheds across the conterminous United States are ranked relative to the...

  20. Private forests, housing growth, and America’s water supply: A report from the Forests on the Edge and Forests to Faucets Projects

    Science.gov (United States)

    M. H. Mockrin; R. L. Lilja; E. Weidner; S. M. Stein; M. A. Carr

    2014-01-01

    America’s private forests provide a vast array of public goods and services, including abundant, clean surface water. Forest loss and development can affect water quality and quantity when forests are removed and impervious surfaces, such as paved roads, spread across the landscape. We rank watersheds across the conterminous United States according to the contributions...

  1. [Influence of land use change on dissolved organic carbon export in Naoli River watershed. Northeast China].

    Science.gov (United States)

    Yin, Xiao-min; Lyu, Xian-guo; Liu, Xing-tu; Xue, Zhen-shan

    2015-12-01

    The present study was conducted to evaluate the influence of land use change on dissolved organic carbon (DOC) export in Naoli River watershed, Northeast China. Seasonal variation of DOC concentrations of the river water and its relationship with land use in the whole watershed and 100 m riparian zone at the annual average scale were analyzed using the method of field sampling, laboratory analysis, GIS and statistics analysis. The results showed that the concentrations of DOC under base flow conditions in spring and summer were significantly higher than that in fall in the study watershed. The seasonal trend of DOC concentrations in wetland-watersheds was similar to that in all the sub-watersheds, while significantly different from that in non-wetland watersheds. On the annual average scale, percentage of wetland in the whole watershed and paddy field in the 100 m riparian zone had positive relationship with the DOC concentration in the river water, while percentage of forest in the whole watershed had negative relationship with it (P watershed played a significant role in the seasonal variation of DOC in river water of Naoli River watershed. Wetland in the watershed and paddy field in the 100 m riparian zone significantly promoted DOC export, while forest alleviated it. Land use change in the watershed in the past few decades dramatically changed the DOC balance of river water.

  2. Climate Change, Forests, and Water Supply: Managing to Reduce Vulnerability in Central Nova Scotia

    Science.gov (United States)

    Steenberg, J.; Duinker, P.

    2009-12-01

    Global climate change is increasingly relevant in managing Canada’s forests sustainably. Forest managers are faced with the necessity of incorporating climate change into forest management plans. The formulation and evaluation of potential management strategies to contend with expected impacts of climate change will be necessary to reduce forest sector vulnerability. The Halifax Regional Water Commission manages forest watersheds for the purpose of supplying clean water to much of the Halifax Regional Municipality. The purpose of this study is to characterize the future forest structure of the two principal watersheds supplying the Halifax Regional Municipality using simulation modelling and to develop a framework of adaptive forest management. A combination of uncertainty analysis, sensitivity analysis, and field data collection are used to refine, calibrate, and validate the spatially dynamic landscape disturbance model LANDIS-II prior to the incorporation of climate change scenarios into model simulations. Final model-based analysis will inform framework development dedicated to improving watershed resilience in the face of future climate change. This study is applicable to forest management under a changing climate, but also has further significance to water security, as watershed management and point-source protection are tightly linked to forest management.

  3. Watershed Conservation in the Long Run

    DEFF Research Database (Denmark)

    Kaiser, Brooks

    2014-01-01

    We studied unanticipated long-run outcomes of conservation activities that occurred in forested watersheds on O`ahu, Hawaii, in the early twentieth century. The initial general impetus for the conservation activities was to improve irrigation surface water flow for the sugar industry. Industry...... concentration facilitated conservation of entire ecosystems. We investigate the benefits that accrued through dynamic linkages of the hydrological cycle and groundwater aquifer system. This provides a clear example of the need to consider integrated watershed effects, industrial structure, and linkages...... in determining conservation policy. We incorporated remote-sensing data, expert opinion on current watershed quality, and a spatial economic and hydrological model of O`ahu’s freshwater use with reports of conservation activities from 1910–1960 to assess these benefits. We find a 2.3% annual increase...

  4. Controls on mercury and methylmercury deposition for two watersheds in Acadia National Park, Maine.

    Science.gov (United States)

    Johnson, K B; Haines, T A; Kahl, J S; Norton, S A; Amirbahman, Aria; Sheehan, K D

    2007-03-01

    Throughfall and bulk precipitation samples were collected for two watersheds at Acadia National Park, Maine, from 3 May to 16 November 2000, to determine which landscape factors affected mercury (Hg) deposition. One of these watersheds, Cadillac Brook, burned in 1947, providing a natural experimental design to study the effects of forest type on deposition to forested watersheds. Sites that face southwest received the highest Hg deposition, which may be due to the interception of cross-continental movement of contaminated air masses. Sites covered with softwood vegetation also received higher Hg deposition than other vegetation types because of the higher scavenging efficiency of the canopy structure. Methyl mercury (MeHg) deposition was not affected by these factors. Hg deposition, as bulk precipitation and throughfall was lower in Cadillac Brook watershed (burned) than in Hadlock Brook watershed (unburned) because of vegetation type and watershed aspect. Hg and MeHg inputs were weighted by season and vegetation type because these two factors had the most influence on deposition. Hg volatilization was not determined. The total Hg deposition via throughfall and bulk precipitation was 9.4 microg/m(2)/year in Cadillac Brook watershed and 10.2 microg/m(2)/year in Hadlock Brook watershed. The total MeHg deposition via throughfall and bulk precipitation was 0.05 microg/m(2)/year in Cadillac Brook watershed and 0.10 microg/m(2)/year in Hadlock Brook watershed.

  5. Watershed Adaptation Measures to Climate Change Impacts: A case of Kiha Watershed in Albertine Graben

    Science.gov (United States)

    Zizinga, A.

    2017-12-01

    Watershed Adaptation Measures to Climate Change Impacts: A case of Kiha Watershed in Albertine GrabenAlex Zizinga1, Moses Tenywa2, Majaliwa Jackson Gilbert1, 1Makerere University, Department of Environmental Sciences, O Box 7062, Kampala, Uganda 1Makerere University, Department of Agricultural Production, P.O Box 7062, Kampala, Uganda Corresponding author: azizinga@caes.mak.ac.ug AbstractThe most pressing issues local communities in Uganda are facing result from land-use and land cover changes exacerbated by climate change impacts. A key issue is the documentation of land-cover changes visible with the ongoing clearance of remaining forests, bush-lands and wetlands for expanding farmland for sugarcane production, producing charcoal and collecting firewood for local distilleries using imported molasses. Decision-makers, resource managers, farmers and practitioners must build their capacity for adaptive measures. Here we present the potential impacts of climate change on watershed hydrological processes in the River Kiha Watershed, located in Western Uganda, Lake Albert Water Management Zone, by using social learning techniques incorporating water users, local stakeholders and researchers. The research team examined different farming and economic activities within the watershed to assess their impacts on catchment water resources, namely on water quality and discharge of river Kiha. We present the impacts of locally induced climate change, which are already manifested in increasing seasonal variability of rainfall. The study aims at answering questions posed by local communities and stakeholders about climate change and its effects on livelihood and key resources, specifically water and soils within the Kiha watershed. Key words: Climate change impacts, Social Learning and Watershed Management

  6. Air Pollution and Watershed Research in the Central Sierra Nevada of California: Nitrogen and Ozone

    Directory of Open Access Journals (Sweden)

    Carolyn Hunsaker

    2007-01-01

    Full Text Available Maintaining healthy forests is the major objective for the Forest Service scientists and managers working for the U.S. Department of Agriculture. Air pollution, specifically ozone (O3 and nitrogenous (N air pollutants, may severely affect the health of forest ecosystems in the western U.S. Thus, the monitoring of air pollution concentration and deposition levels, as well as studies focused on understanding effects mechanisms, are essential for evaluation of risks associated with their presence. Such information is essential for development of proper management strategies for maintaining clean air, clean water, and healthy ecosystems on land managed by the Forest Service. We report on two years of research in the central Sierra Nevada of California, a semi-arid forest at elevations of 1100–2700 m. Information on O3 and N air pollutants is obtained from a network of 18 passive samplers. We relate the atmospheric N concentration to N concentrations in streams, shallow soil water, and bulk deposition collectors within the Kings River Experimental Watershed. This watershed also contains an intensive site that is part of a recent Forest Service effort to calculate critical loads for N, sulfur, and acidity to forest ecosystems. The passive sampler design allows for extensive spatial measurements while the watershed experiment provides intensive spatial data for future analysis of ecosystem processes.

  7. Evapotranspiration from two peatland watersheds

    Science.gov (United States)

    Roger R. Bay

    1968-01-01

    Measurements of precipitation, runoff, and bog water table levels have provided data for the calculation of evapotranspiration from two forested peatland watersheds near Grand Rapids, Minnesota (ca. 47? 32'N, 93? 28'W). Continuous hydrologie records were collected on one experimental bog for 6 years (1961-1966) and on the other for the past 2 years (1965-1966...

  8. Some references on watershed management.

    Science.gov (United States)

    W.E. Bullard

    1950-01-01

    Several of you in the field administrative jobs have asked for a summary of available information from forest influences studies relating to watershed management practices. This paper hits some of the high spots, giving a brief survey of European and American studies and recommendations that may be applicable within our region. Further, it contains a few pertinent...

  9. Integrating land use and climate change scenarios and models into assessment of forested watershed services in Southern Thailand.

    Science.gov (United States)

    Trisurat, Yongyut; Eawpanich, Piyathip; Kalliola, Risto

    2016-05-01

    The Thadee watershed, covering 112km(2), is the main source of water for agriculture and household consumption in the Nakhon Srithammarat Province in Southern Thailand. As the natural forests upstream have been largely degraded and transformed to fruit tree and rubber plantations, problems with landslides and flooding have resulted. This research attempts to predict how further land-use/land-cover changes during 2009-2020 and conceivable changes in rainfall may influence the future levels of water yield and sediment load in the Thadee River. Three different land use scenarios (trend, development and conservation) were defined in collaboration with the local stakeholders, and three different rainfall scenarios (average rainfall, climate change and extreme wet) were determined on the basis of literature sources. Spatially explicit empirical modelling was employed to allocate future land demands and to assess the contributions of land use and rainfall changes, considering both their separate and combined effects. The results suggest that substantial land use changes may occur from a large expansion of rubber plantations in the upper sub-watersheds, especially under the development land use scenario. The reduction of the current annual rainfall by approximately 30% would decrease the predicted water yields by 38% from 2009. According to the extreme rainfall scenario (an increase of 36% with respect to current rainfall), an amplification of 50% of the current runoff could result. Sensitivity analyses showed that the predicted soil loss is more responsive to changes in rainfall than to the compared land use scenarios alone. However, very high sediment load and runoff levels were predicted on the basis of combined intensified land use and extreme rainfall scenarios. Three conservation activities-protection, reforestation and a mixed-cropping system-are proposed to maintain the functional watershed services of the Thadee watershed region. Copyright © 2016 Elsevier Inc

  10. Managing salinity in Upper Colorado River Basin streams: Selecting catchments for sediment control efforts using watershed characteristics and random forests models

    Science.gov (United States)

    Tillman, Fred; Anning, David W.; Heilman, Julian A.; Buto, Susan G.; Miller, Matthew P.

    2018-01-01

    Elevated concentrations of dissolved-solids (salinity) including calcium, sodium, sulfate, and chloride, among others, in the Colorado River cause substantial problems for its water users. Previous efforts to reduce dissolved solids in upper Colorado River basin (UCRB) streams often focused on reducing suspended-sediment transport to streams, but few studies have investigated the relationship between suspended sediment and salinity, or evaluated which watershed characteristics might be associated with this relationship. Are there catchment properties that may help in identifying areas where control of suspended sediment will also reduce salinity transport to streams? A random forests classification analysis was performed on topographic, climate, land cover, geology, rock chemistry, soil, and hydrologic information in 163 UCRB catchments. Two random forests models were developed in this study: one for exploring stream and catchment characteristics associated with stream sites where dissolved solids increase with increasing suspended-sediment concentration, and the other for predicting where these sites are located in unmonitored reaches. Results of variable importance from the exploratory random forests models indicate that no simple source, geochemical process, or transport mechanism can easily explain the relationship between dissolved solids and suspended sediment concentrations at UCRB monitoring sites. Among the most important watershed characteristics in both models were measures of soil hydraulic conductivity, soil erodibility, minimum catchment elevation, catchment area, and the silt component of soil in the catchment. Predictions at key locations in the basin were combined with observations from selected monitoring sites, and presented in map-form to give a complete understanding of where catchment sediment control practices would also benefit control of dissolved solids in streams.

  11. Development of online tools to support GIS watershed analyses

    Science.gov (United States)

    William J. Elliot

    2016-01-01

    In 1996 there was a meeting in Tucson of hydrologists from every Forest Service region, as well as Forest Service research scientists engaged in watershed-related activities. This meeting was organized by the Stream Team (which has since been enveloped by the National Stream and Aquatic Ecology Center). The focus of the meeting was to identify tools that needed to be...

  12. Variation of Annual ET Determined from Water Budgets Across Rural Southeastern Basins Differing in Forest Types

    Science.gov (United States)

    Younger, S. E.; Jackson, C. R.

    2017-12-01

    In the Southeastern United States, evapotranspiration (ET) typically accounts for 60-70% of precipitation. Watershed and plot scale experiments show that evergreen forests have higher ET rates than hardwood forests and pastures. However, some plot experiments indicate that certain hardwood species have higher ET than paired evergreens. The complexity of factors influencing ET in mixed land cover watersheds makes identifying the relative influences difficult. Previous watershed scale studies have relied on regression to understand the influences or low flow analysis to indicate growing season differences among watersheds. Existing studies in the southeast investigating ET rates for watersheds with multiple forest cover types have failed to identify a significant forest type effect, but these studies acknowledge small sample sizes. Trends of decreasing streamflow have been recognized in the region and are generally attributed to five key factors, 1.) influences from multiple droughts, 2.) changes in distribution of precipitation, 3.) reforestation of agricultural land, 4.) increasing consumptive uses, or 5.) a combination of these and other factors. This study attempts to address the influence of forest type on long term average annual streamflow and on stream low flows. Long term annual ET rates were calculated as ET = P-Q for 46 USGS gaged basins with daily data for the 1982 - 2014 water years, >40% forest cover, and no large reservoirs. Land cover data was regressed against ET to describe the relationship between each of the forest types in the National Land Cover Database. Regression analysis indicates evergreen land cover has a positive relationship with ET while deciduous and total forest have a negative relationship with ET. Low flow analysis indicates low flows tend to be lower in watersheds with more evergreen cover, and that low flows increase with increasing deciduous cover, although these relationships are noisy. This work suggests considering forest

  13. Prescribed Burning and Erosion Potential in Mixed Hardwood Forests of Southern Illinois

    Directory of Open Access Journals (Sweden)

    Gurbir Singh

    2017-04-01

    Full Text Available Prescribed fire has several benefits for managing forest ecosystems including reduction of fuel loading and invasive species and enhanced regeneration of desirable tree species. Along with these benefits there are some limitations like nutrient and sediment loss which have not been studied extensively in mixed hardwood forests. The objective of our research was to quantify the amount of sediment movement occurring on a watershed scale due to prescribed fire in a southern Illinois mixed hardwood ecosystem. The research site was located at Trail of Tears State Forest in western Union county, IL, USA and included five watershed pairs. One watershed in each pair was randomly assigned the prescribed burn treatment and the other remained as control (i.e., unburned. The prescribed burn treatment significantly reduced the litter depth with 12.6%–31.5% litter remaining in the prescribed burn treatment watersheds. When data were combined across all watersheds, no significant differences were obtained between burn treatment and control watershed for total suspended solids and sediment concentrations or loads. The annual sediment losses varied from 1.41 to 90.54 kg·ha−1·year−1 in the four prescribed burn watersheds and 0.81 to 2.54 kg·ha−1·year−1 in the four control watersheds. Prescribed burn watershed 7 showed an average soil sediment loss of 4.2 mm, whereas control watershed 8 showed an average accumulation of sediments (9.9 mm, possibly due to steeper slopes. Prescribed burning did not cause a significant increase in soil erosion and sediment loss and can be considered acceptable in managing mixed hardwood forests of Ozark uplands and the Shawnee Hills physiographic regions of southern Illinois.

  14. How to restore dry forest ecosystems

    OpenAIRE

    Nalvarte, Jaime

    2012-01-01

    AIDER is a Peruvian non-governmental organization working since 1992 on forest management activities, watershed management and urban forest management on tropical humid and dry forest at a national level. AIDER and the José Ignacio Távara Pasapera rural community have been working on dry forest management and recovery since 1992. This paper summarizes the activity of AIDER in the dry forests for the purpose of recovering degraded forest areas and conserve existing forests by developing sustai...

  15. The Application of a WEPP Technology to a Complex Watershed Analysis

    Science.gov (United States)

    Elliot, William; Miller, Ina Sue; Dobre, Mariana

    2017-04-01

    Forest restoration activities are essential in many forest stands, where previous management and fire suppression has resulted in stands with high density, diseased trees and excessive fuel loads. Trying to balance the watershed impacts of restoration activities such as thinning, selective harvesting, and prescribed fire against the significant impact of wildfire is challenging. The process is further aggravated by the necessity of a road network if management activities include timber removal. We propose to present an approach to a watershed analysis for a 3400-ha of fuel reduction project within an 18,0000-ha sensitive watershed in the Nez Perce National Forest in Northern Idaho, USA. The FlamMap fire spread model was first used to predict the distribution of potential fire severity on the landscape for the current fuel load, and for a landscape that had been treated by thinning and/or prescribed fire. FlamMap predicts the flame length by 30-m pixel as a function of fuel load and water content, wind speed, and slope steepness and aspect. The flame length distribution was then classified so that the distribution of burn severity (unburned, low, moderate and high severity) was similar to the distributions observed on recent wildfires in the Forest. The flame length classes determined for the current fuel loads were also used for the treated condition flame lengths, where predominantly unburned or low severity fire severities were predicted. The burn severity maps were uploaded to a web site that was developed to provide soil and management files reflecting burn severity and soil texture, formatted for the Geospatial interface to the Water Erosion Prediction Project (GeoWEPP). The study area was divided into 40 sub watersheds under 2.5 km2 each for GeoWEPP analysis. GeoWEPP was run for an undisturbed forest; for the burn severity following wildfire for the current and treated fuel loads; for prescribed fire, either broadcast or jack pot burn; and for thinning either

  16. 76 FR 51936 - Coconino and Kaibab National Forests, Arizona, Four-Forest Restoration Initiative

    Science.gov (United States)

    2011-08-19

    ...) 527-3620. FOR FURTHER INFORMATION CONTACT: Henry Provencio, 4 FRI Team Leader at (928) 226-4684 or via... natural role in these fire- adapted ponderosa pine forests. As a result, the forests have shifted from... important role on the landscape for hydrological function of watersheds and they are very important for...

  17. Biogeochemical and Hydrological Controls on Mercury and Methylmercury in First Order Coastal Plain Watersheds of the Chesapeake Bay

    Science.gov (United States)

    Heyes, A.; Gilmour, C. C.; Bell, J. T.; Butera, D.; McBurney, A. W.

    2015-12-01

    Over the past 7 years we made use of the long-term research site at the Smithsonian Environmental Research Center (SERC) in central Maryland to study the fluxes of mercury (Hg) and methylmercury (MeHg) in three small first-order mid-Atlantic coastal plain watersheds. One watershed is entirely forested, one watershed is primarily agriculture with a forested stream buffer, and one watershed is mixed land use but contains a beaver produced wetland pond. Our initial goals were to assess watershed Hg yields in the mid-Atlantic and to establish a baseline prior to implementation of Hg emissions controls. All three studied watersheds produced relatively high yields of Hg, with the greatest yield coming from the forested watershed. Our initial evaluation of three watersheds showed that MeHg production and flux could also be high, but varied dramatically among watersheds and across years and seasons. During each year we observed episodic MeHg production in the spring and sometimes during prolonged high-flow storm events in the fall. The observed spring maxima of MeHg release coincided with development of anoxia in riparian groundwater. MeHg accumulation in riparian groundwater began once nitrate was depleted and either iron accumulation or sulfate depletion of groundwater began. We propose the presence of nitrate was modulating MeHg production through the suppression of sulfate and iron reducers and perhaps methanogens. As sulfate is not limiting in any of the watersheds owing to the sediments marine origin, we hypothesize the depletion of nitrate allows sulfate reducing bacteria to now utilize available carbon. Although wetlands are generally thought of as the primary zones of MeHg production in watersheds, shallow riparian groundwaters very close to the stream appear to play that role in SERC Coastal Plain watersheds. We hypothesize that the balance between nitrate, sulfate and other microbial electron acceptors in watersheds is a major control on MeHg production. Land

  18. Managing the forest for more than the trees: effects of experimental timber harvest on forest Lepidoptera.

    Science.gov (United States)

    Summerville, Keith S

    2011-04-01

    Studies of the effects of timber harvest on forest insect communities have rarely considered how disturbance from a range of harvest levels interacts with temporal variation in species diversity to affect community resistance to change. Here I report the results of a landscape-scale, before-and-after, treatment-control experiment designed to test how communities of forest Lepidoptera experience (1) changes in species richness and composition and (2) shifts in species dominance one year after logging. I sampled Lepidoptera from 20 forest stands allocated to three harvest treatments (control, even-aged shelterwood or clearcuts, and uneven-aged group selection cuts) within three watersheds at Morgan-Monroe State Forest, Indiana, USA. Moths were sampled from all forest stands one year prior to harvest in 2007 and immediately post-harvest in 2009. Species composition was most significantly affected by temporal variation between years, although uneven-aged management also caused significant changes in lepidopteran community structure. Furthermore, species richness of Lepidoptera was higher in 2007 compared to 2009 across all watersheds and forest stands. The decrease in species richness between years, however, was much larger in even-aged and uneven-aged management units compared to the control. Furthermore, matrix stands within the even-aged management unit demonstrated the highest resistance to species loss within any management unit. Species dominance was highly resistant to effects of timber harvest, with pre- and post-harvest values for Simpson diversity nearly invariant. Counter to prediction, however, the suite of dominant taxa differed dramatically among the three management units post-harvest. My results suggest that temporal variation may have strong interactions with timber harvest, precipitating loss of nearly 50% species richness from managed stands regardless of harvest level. Even-aged management, however, appeared to leave the smallest "footprint" on moth

  19. Forest management practices and silviculture. Chapter 12.

    Science.gov (United States)

    Donald A. Perala; Elon S. Verry

    2011-01-01

    This chapter is an overview of forest management and silviculture practices, and lessons learned, on the Marcell Experimental Forest (MEF). The forests there are a mosaic of natural regeneration and conifer plantations. Verry (1969) described forest-plant communities in detail for the study watersheds (Sl through S6) on the MEF. The remaining area is described in...

  20. Forests and water: effects of forest management on floods, sedimentation, and water supply

    Science.gov (United States)

    Henry W. Anderson; Marvin D. Hoover; Kenneth G. Reinhart

    1976-01-01

    From the background of more than 100 years' collective experience in watershed research and from comprehensive review of the literature of forest hydrology, the authors summarize what is known about the forest's influence on the water resource, particularly the effects of current forestry practices. They first examine the fundamental hydrologic processes in...

  1. Forest cover changes due to hydrocarbon extraction disturbance in central Pennsylvania (2004–2010)

    Science.gov (United States)

    Roig-Silva, Coral; Slonecker, Terry; Milheim, Lesley; Ballew, Jesse R.; Winters, S. Gail

    2016-01-01

    The state of Pennsylvania has a long history of oil and gas extraction. In recent years with advances in technology such as hydraulic fracturing, hydrocarbon sources that were not profitable in the past are now being exploited. Here, we present an assessment of the cumulative impact of oil and gas extraction activities on the forests of 35 counties in Pennsylvania and their intersecting sub-watersheds between 2004 and 2010. The assessment categorizes counties and sub-watersheds based on the estimated amount of change to forest cover in the area. From the data collected we recognize that although forest cover has not been greatly impacted (with an average loss of percent forest coverage of 0.16% at the county level), landscape structure is affected. Increase in edge forest and decrease in interior forest is evident in many of the counties and sub-watersheds examined. These changes can have a detrimental effect on forest biodiversity and dynamics.

  2. Assessing changes to in-stream turbidity following construction of a forest road in West Virginia

    Science.gov (United States)

    Jingxin Wang; Pamela J. Edwards; William A. Goff

    2011-01-01

    Two forested headwater watersheds were monitored to examine changes to in-stream turbidity following the construction of a forest haul road. One watershed was used as an undisturbed reference, while the other had a 0.92-km (0.57-mi) haul road constructed in it. The channels in both are intermittent tributaries of the Left Fork of Clover Run in the Cheat River watershed...

  3. 76 FR 18713 - Malheur National Forest; Oregon; Malheur National Forest Site-Specific Invasive Plants Treatment...

    Science.gov (United States)

    2011-04-05

    ... species that currently are not found on the Forest. Treatment could be anywhere on Forest Service system.... Electronic comments in acceptable plain text (.txt), rich text (.rtf), or Word (.doc) may be submitted to... wildlife habitat, out-compete native plants, impair water quality and watershed health, and adversely...

  4. Eleven-year response of foliar chemistry to chronic nitrogen and sulfur additions at the Bear Brook Watershed in Maine

    Science.gov (United States)

    Jose Alexander Elvir; Lindsey Rustad; G. Bruce Wiersma; Ivan Fernandez; Alan S. White; Gregory J. White

    2005-01-01

    The foliar chemistry of sugar maple (Acer saccharum Marsh.), American beech (Fagus grandifolia Ehrh.), and red spruce (Picea rubens Sarg.) was studied from 1993 to 2003 at the Bear Brook Watershed in Maine (BBWM). The BBWM is a paired-watershed forest ecosystem study, with one watershed treated bimonthly since...

  5. A problem analysis and program for watershed-management research in the White Mountains of New Hampshire

    Science.gov (United States)

    George R., Jr. Trimble

    1959-01-01

    The U. S. Forest Service was authorized by Congress in late summer of 1954 to conduct watershed management research in New Hampshire. The purpose of this work is to determine the effect of forest cover on streamflow: the influence of forest cover type, forest condition, and forest treatment practices on water yield, rate of delivery, and on water quality. This is the...

  6. Influences on wood load in mountain streams of the Bighorn National Forest, Wyoming, USA.

    Science.gov (United States)

    Nowakowski, Amy L; Wohl, Ellen

    2008-10-01

    We documented valley and channel characteristics and wood loads in 19 reaches of forested headwater mountain streams in the Bighorn National Forest of northern Wyoming. Ten of these reaches were in the Upper Tongue River watershed, which has a history of management including timber harvest, tie floating, and road construction. Nine reaches were in the North Rock Creek watershed, which has little history of management activities. We used these data to test hypotheses that (i) valley geometry correlates with wood load, (ii) stream gradient correlates with wood load, and (iii) wood loads are significantly lower in managed watersheds than in otherwise similar unmanaged watersheds. Statistical analyses of the data support the first and third hypotheses. Stream reaches with steeper valley side slopes tend to have higher wood loads, and reaches in managed watersheds tend to have lower wood loads than reaches in unmanaged watersheds. Results do not support the second hypothesis. Shear stress correlated more strongly with wood load than did stream gradient, but statistical models with valley-scale variables had greater explanatory power than statistical models with channel-scale variables. Wood loads in stream reaches within managed watersheds in the Bighorn National Forest tend to be two to three times lower than wood loads in unmanaged watersheds.

  7. Optimization of Southeastern Forest Biomass Crop Production: A Watershed Scale Evaluation of the Sustainability and Productivity of Dedicated Energy Crop and Woody Biomass Operations

    Energy Technology Data Exchange (ETDEWEB)

    Chescheir, George M. [North Carolina State Univ., Raleigh, NC (United States); Nettles, Jami E, [Weyerhaeuser Company; Youssef, Mohamed [North Carolina State Univ., Raleigh, NC (United States); Birgand, Francois [North Carolina State Univ., Raleigh, NC (United States); Amatya, Devendra M. [United States Forest Service; Miller, Darren A. [Weyerhaeuser Company; Sucre, Eric [Weyerhaeuser Company; Schilling, Erik [National Council for Air and Stream Improvement, Inc.; Tian, Shiying [North Carolina State Univ., Raleigh, NC (United States); Cacho, Julian F. [Argonne National Lab. (ANL), Argonne, IL (United States); Bennett, Erin M. [Ecosystem Planning and Restoration, LLC; Carter, Taylor [HDR; Bowen, Nicole Dobbs [Engineering Design Consultants; Muwamba, Augustine [College of Charleston; Panda, Sudhanshu [University of North Georgia; Christopher, Sheila [Univ. of Notre Dame, IN (United States); Phillips, Brian D. [North Carolina State Univ., Raleigh, NC (United States); Appelboom, Timothy [NC Department of Environmental Quality; Skaggs, Richard W. [North Carolina State Univ., Raleigh, NC (United States); Greene, Ethan J. [Land Trust for Central North Carolina; Marshall, Craig D. [Mississippi State University; Allen, Elizabeth [North Carolina State Univ., Raleigh, NC (United States); Schoenholtz, Stephen H. [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States)

    2018-04-12

    Growing switchgrass (Panicum virgatum L.) as an intercrop in managed loblolly pine (Pinus taeda L.) plantations has emerged as a potential source of bioenergy feedstock. Utilizing land resources between pine trees to produce an energy crop can potentially reduce the demand for land resources used to produce food; however, converting conventionally managed forest land to this new intercropping system constitutes changes in land use and associated management practices, which may affect the environmental and economic sustainability of the land.

    The overall objective of this project is to evaluate the environmental effects of large-scale forest bioenergy crop production and utilize these results to optimize cropping systems in a manner that protects the important ecosystem services provided by forests while contributing to the development of a sustainable and economically-viable biomass industry in the southeastern United States.

    Specific objectives are to:

    1. Quantify the hydrology of different energy crop production systems in watershed scale experiments on different landscapes in the southeast.
    2. Quantify the nutrient dynamics of energy crop production systems in watershed scale experiments to determine the impact of these systems on water quality.
    3. Evaluate the impacts of energy crop production on soil structure, fertility, and organic matter.
    4. Evaluate the response of flora and fauna populations and habitat quality to energy crop production systems.
    5. Develop watershed and regional scale models to evaluate the environmental sustainability and productivity of energy crop and woody biomass operations.
    6. Quantify the production systems in terms of bioenergy crop yield versus the energy and economic costs of production.
    7. Develop and evaluate best management practice guidelines to ensure the environmental sustainability of energy crop production systems.
    Watershed and plot scale studies

  8. Aboveground biomass and nutrient accumulation 20 years after clear-cutting a southern Appalachian watershed

    Science.gov (United States)

    Katherine J. Elliott; Lindsay R. Boring; Wayne T. Swank

    2002-01-01

    In 1975, we initiated a long-term interdisciplinary study of forest watershed ecosystem response to clear- cutting and cable logging in watershed 7 at the Coweeta Hydrologic Laboratory in the southern Appalachian Mountains of North Carolina. This paper describes ~20 years of change in species composition, aboveground biomass, leaf area index (LAI),...

  9. Comparison of stream nutrient conditions in a subtropical lowland watershed to EPA suggested criteria

    Science.gov (United States)

    April Mason; Y. Jun Xu; Johnny M. Grace

    2007-01-01

    Nutrients such as nitrogen, phosphorus and organic carbon are essential to the health and diversity of stream ecosystems. However, excess nutrients can cause eutrophication, resulting in overgrowth of aquatic plants and decline of the ecosystem diversity. A paired-watershed study was initiated in a subtropical forested watershed within the Ouachita River Basin in...

  10. Evapotranspiration sensitivity to air temperature across a snow-influenced watershed: Space-for-time substitution versus integrated watershed modeling

    Science.gov (United States)

    Jepsen, S. M.; Harmon, T. C.; Ficklin, D. L.; Molotch, N. P.; Guan, B.

    2018-01-01

    Changes in long-term, montane actual evapotranspiration (ET) in response to climate change could impact future water supplies and forest species composition. For scenarios of atmospheric warming, predicted changes in long-term ET tend to differ between studies using space-for-time substitution (STS) models and integrated watershed models, and the influence of spatially varying factors on these differences is unclear. To examine this, we compared warming-induced (+2 to +6 °C) changes in ET simulated by an STS model and an integrated watershed model across zones of elevation, substrate available water capacity, and slope in the snow-influenced upper San Joaquin River watershed, Sierra Nevada, USA. We used the Soil Water and Assessment Tool (SWAT) for the watershed modeling and a Budyko-type relationship for the STS modeling. Spatially averaged increases in ET from the STS model increasingly surpassed those from the SWAT model in the higher elevation zones of the watershed, resulting in 2.3-2.6 times greater values from the STS model at the watershed scale. In sparse, deep colluvium or glacial soils on gentle slopes, the SWAT model produced ET increases exceeding those from the STS model. However, watershed areas associated with these conditions were too localized for SWAT to produce spatially averaged ET-gains comparable to the STS model. The SWAT model results nevertheless demonstrate that such soils on high-elevation, gentle slopes will form ET "hot spots" exhibiting disproportionately large increases in ET, and concomitant reductions in runoff yield, in response to warming. Predicted ET responses to warming from STS models and integrated watershed models may, in general, substantially differ (e.g., factor of 2-3) for snow-influenced watersheds exhibiting an elevational gradient in substrate water holding capacity and slope. Long-term water supplies in these settings may therefore be more resilient to warming than STS model predictions would suggest.

  11. Wetland influence on mercury fate and transport in a temperate forested watershed

    International Nuclear Information System (INIS)

    Selvendiran, Pranesh; Driscoll, Charles T.; Bushey, Joseph T.; Montesdeoca, Mario R.

    2008-01-01

    The transport and fate of mercury (Hg) was studied in two forest wetlands; a riparian peatland and an abandoned beaver meadow. The proportion of total mercury (THg) that was methyl mercury (% MeHg) increased from 2% to 6% from the upland inlets to the outlet of the wetlands. During the growing season, MeHg concentrations were approximately three times higher (0.27 ng/L) than values during the non-growing season (0.10 ng/L). Transport of Hg species was facilitated by DOC production as indicated by significant positive relations with THg and MeHg. Elevated concentrations of MeHg and % MeHg (as high as 70%) were found in pore waters of the riparian and beaver meadow wetlands. Groundwater interaction with the stream was limited at the riparian peatland due to the low hydraulic conductivity of the peat. The annual fluxes of THg and MeHg at the outlet of the watershed were 2.3 and 0.092 μg/m 2 -year respectively. - Wetlands are sources of THg and MeHg; the production of MeHg is seasonally dependent and driven by sulfate reduction in wetlands

  12. Wetland influence on mercury fate and transport in a temperate forested watershed

    Energy Technology Data Exchange (ETDEWEB)

    Selvendiran, Pranesh [Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY 13244 (United States)], E-mail: pselvend@syr.edu; Driscoll, Charles T. [Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY 13244 (United States)], E-mail: ctdrisco@syr.edu; Bushey, Joseph T. [Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY 13244 (United States)], E-mail: jtbushey@syr.edu; Montesdeoca, Mario R. [Department of Civil and Environmental Engineering, Syracuse University, Syracuse, NY 13244 (United States)], E-mail: mmontesd@syr.edu

    2008-07-15

    The transport and fate of mercury (Hg) was studied in two forest wetlands; a riparian peatland and an abandoned beaver meadow. The proportion of total mercury (THg) that was methyl mercury (% MeHg) increased from 2% to 6% from the upland inlets to the outlet of the wetlands. During the growing season, MeHg concentrations were approximately three times higher (0.27 ng/L) than values during the non-growing season (0.10 ng/L). Transport of Hg species was facilitated by DOC production as indicated by significant positive relations with THg and MeHg. Elevated concentrations of MeHg and % MeHg (as high as 70%) were found in pore waters of the riparian and beaver meadow wetlands. Groundwater interaction with the stream was limited at the riparian peatland due to the low hydraulic conductivity of the peat. The annual fluxes of THg and MeHg at the outlet of the watershed were 2.3 and 0.092 {mu}g/m{sup 2}-year respectively. - Wetlands are sources of THg and MeHg; the production of MeHg is seasonally dependent and driven by sulfate reduction in wetlands.

  13. Protect and Restore Red River Watershed, 2007-2008 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Bransford, Stephanie [Nez Perce Tribe Fisheries/Watershed Program

    2009-05-04

    The Nez Perce Tribe Department of Fisheries Resource Management, Watershed Division approaches watershed restoration with a ridge-top to ridge-top approach. The Nez Perce Tribe (NPT) and the Nez Perce National Forest (NPNF) have formed a partnership in completing watershed restoration activities, and through this partnership more work is accomplished by sharing funding and resources in our effort. The Nez Perce Tribe began watershed restoration projects within the Red River Watershed of the South Fork Clearwater River in 2001. Progress has been made in restoring the watershed through road decommissioning and culvert replacement. From completing a watershed assessment to two NEPA efforts and a final stream restoration design, we will begin the effort of restoring the mainstem channel of Red River to provide spawning and rearing habitat for anadromous and resident fish species. Roads have been surveyed and prioritized for removal or improvement as well as culverts being prioritized for replacement to accommodate fish passage throughout the watershed. Another major, and extremely, important component of this project is the Red River Meadow Conservation Easement. We have begun the process of pursuing a conservation easement on approximately 270 acres of prime meadow habitat (Red River runs through this meadow and is prime spawning and rearing habitat).

  14. Long-term forest watershed studies in the Southwest: recycled for wildfire and prescribed fire

    Science.gov (United States)

    Daniel G. Neary; Gerald J. Gottfried; Peter F. Ffolliott; Boris Poff

    2012-01-01

    A hydrologic research network was established in Arizona in the 1950s and 1960s called the Arizona Watershed Program (Baker et al. 1999). It consisted of a number of public agencies and private groups interested in obtaining more water for future economic growth while maintaining the State's watersheds in good condition. As part of the Program. paired watershed...

  15. Status and management of watersheds in the Upper Pokhara Valley, Nepal

    Science.gov (United States)

    Thapa, Gopal B.; Weber, Karl E.

    1995-07-01

    Contributing to the debate on the causes of Himalayan environmental degradation, the status and management of four watersheds in the Upper Pokhara Valley were studied using information available from land use analysis, household surveys conducted in 1989 and 1992, deliberations held with villagers, and field observations. Accordingly, areas under forests and grazing lands were found being depleted at relatively high rates between 1957 and 1978 due mainly to the government policy of increasing national revenue by expansion of agricultural lands, nationalization of forests, steadily growing population, and dwindling household economy. Despite the steady growth of population, this process had remarkably slackened since 1978, owing primarily to remaining forests being located in very, steep slopes and implementation of the community forestry program. Forests with relatively sparase tree density, however, and grazing lands in the vicinity of settlements have been undergoing degradation due to fuelwood and fodder collection and livestock grazing. In many instances, this is aggravated by weak resource management institutions. Being particularly aware of the economic implication of land degradation, farmers have adopted assorted land management practices. Still a substantial proportion of bari lands in the hill slopes is vulnerable to accelerating degradation, as the arable cropping system is being practiced there as well. The perpetuation of the local subsistence economy is certain to lead, to a further deterioration of the socioeconomic and environmental conditions of watersheds. To facilitate environmental conservation and ecorestructuring for sustainable development, a broad watershed management strategy is outlined with focus on alleviating pressure on natural resources.

  16. Coupling Evapotranspiration and Watershed Storage to Assess the Impact of Forest Disturbance on Low Flows

    Science.gov (United States)

    Brena Naranjo, J.; Stahl, K.; Weiler, M.

    2009-05-01

    Low flows are important for water-supply planning and design, and maintenance of quantity and quality of water for irrigation, recreation, and fish and wildlife conservation. There have been concerns recently that climate warming and land cover changes due to an unprecedented pine beetle epidemic in British Columbia, Canada, may cause a deterioration of water quantity during low flow periods and at certain times may become a hazard to ecosystem and to water management schemes. A study to characterize the sensitivity of the low flow regimes was performed for several mainly forested catchments located within the Fraser River basin. Here, summer low flows are maintained through the release of water from groundwater and riparian storage, lakes and wetlands, but are reduced by high evapotranspiration rates in the catchments. Since evapotranspiration in British Columbia accounts around 40% of the precipitation, the first part of this work was focused on the assessment of the relationship between the potential evapotranspiration (PET) and the actual evapotranspiration (AET) for undisturbed and disturbed landscapes which is expected to influence the hydrological behavior during the low-flow season. Through its influence on evapotranspiration, forest age appears to play an important role in the water balance. The second part of the study implemented a forest age dependent calculation of AET into a parsimonious water balance model, which was applied to simulate the sensitivity of the flow regimes of 15 non regulated watersheds to changes after the beginning of the pine beetle epidemic at a large scale. The model input was derived from disaggregated gridded 30-year climate normals. Since the geologic and topographic properties are first order controls on water storage and release of the examined catchments a framework for regionalization of these properties into ungauged catchments was developed. Furthermore, the interaction between forest disturbance and evapotranspiration

  17. A large-scale throughfall manipulation experiment on Walker Branch Watershed

    International Nuclear Information System (INIS)

    Turner, R.S.; Hanson, P.J.; Huston, M.A.; Garten, C.T. Jr.; Mulholland, P.J.

    1992-01-01

    A throughfall displacement experiment is being performed in a mixed-age upland-oak forest on the upper slopes of Walker Branch Watershed in eastern Tennessee to investigate the effects of decreased and increased rainfall on individual species and ecosystem processes at the spatial scale of forest stands. Approximately 25% of the throughfall on the ''dry'' plot will be collected in polyethylene troughs suspended above the forest floor and the water transferred by gravity through pipes across the control plot for distribution onto the ''wet'' plot. Each plot is approximately 0.6 ha in size. The 25% reduction in soil moisture anticipated for the dry plot is equivalent to the driest growing season of the 1980's drought, which was correlated with sapling mortality and reduced growth of yellow poplar on the watershed. The experimental treatments will last at least 5 years. A wide range of biological and chemical characteristics of forest stands win be investigated, including: forest growth and physiological responses of major tree and understory species, leaf area index, herbivory, litter fall, understory competition, litter decomposition, soil organic matter and microbial populations, nutrient availability, soil and soil solution chemistry, and biogeochemical cycling processes. Data on vegetation growth, mortality, and reproduction will be used in existing models of community structure to produce estimates of potential changes in species composition over longer time periods resulting from wet versus dry experimental scenarios

  18. A Knowledge-Based Information Management System for Watershed Analysis in the Pacific Northwest U.S.

    Science.gov (United States)

    Keith Reynolds; Patrick Cunningham; Larry Bednar; Michael Saunders; Michael Foster; Richard Olson; Daniel Schmoldt; Donald Latham; Bruce Miller; John Steffenson

    1996-01-01

    The Pacific Northwest Research Station (USDA Forest Service) is developing a knowledge-based information management system to provide decision support for watershed analysis. The system includes: (1) a GIS interface that allows users to navigate graphically to specific provinces and watersheds and display a variety of themes (vegetation, streams, roads, topography, etc...

  19. Experimental Watershed Study Designs: A Tool for Advancing Process Understanding and Management of Mixed-Land-Use Watersheds

    Science.gov (United States)

    Hubbart, J. A.; Kellner, R. E.; Zeiger, S. J.

    2016-12-01

    Advancements in watershed management are both a major challenge, and urgent need of this century. The experimental watershed study (EWS) approach provides critical baseline and long-term information that can improve decision-making, and reduce misallocation of mitigation investments. Historically, the EWS approach was used in wildland watersheds to quantitatively characterize basic landscape alterations (e.g. forest harvest, road building). However, in recent years, EWS is being repurposed in contemporary multiple-land-use watersheds comprising a mosaic of land use practices such as urbanizing centers, industry, agriculture, and rural development. The EWS method provides scalable and transferrable results that address the uncertainties of development, while providing a scientific basis for total maximum daily load (TMDL) targets in increasing numbers of Clean Water Act 303(d) listed waters. Collaborative adaptive management (CAM) programs, designed to consider the needs of many stakeholders, can also benefit from EWS-generated information, which can be used for best decision making, and serve as a guidance tool throughout the CAM program duration. Of similar importance, long-term EWS monitoring programs create a model system to show stakeholders how investing in rigorous scientific research initiatives improves decision-making, thereby increasing management efficiencies through more focused investments. The evolution from classic wildland EWS designs to contemporary EWS designs in multiple-land-use watersheds will be presented while illustrating how such an approach can encourage innovation, cooperation, and trust among watershed stakeholders working to reach the common goal of improving and sustaining hydrologic regimes and water quality.

  20. Monitoring deforestation and urbanization growth in rawal watershed area using remote sensing and gis techniques

    International Nuclear Information System (INIS)

    Saeed, M.A.; Ashraf, A.

    2011-01-01

    The Rawal watershed in Pothwar region of Pakistan has undergone significant changes in its environmental conditions and landuse activities due to numerous socio-economic and natural factors. These ultimately influence the livelihood of the inhabitants of the area. The connected environmental changes are resulting in accelerated land degradation, deforestation, and landslides. In the present study, spatio-temporal behaviour of landuse/landcover in the Rawal watershed area was investigated using Remote Sensing (RS) and Geographical Information System (GIS) techniques. Satellite image data of LANDSAT ETM+ of 1992, 2000 and 2010 periods were processed and analyzed for detecting land use change and identifying risk prone locations in the watershed area. The study results revealed significant changes in the coverage of conifer forest (34 % decrease), scrub forest (29 % decrease) and settlement (231 % increase) during the decade 1992-2010. The rate of decline in conifer class is about 19 ha/annum while that of scrub class is 223 ha/annum. In both the cases, the rates of decrease were higher during the period 1992-2000 than the period 2000-2010. The Agriculture land has shown an increase of about 1.8% while built-up land had increased almost four folds, i.e. from 2.6 % in 1992 to 8.7 % in 2010. The growth in urbanization may result in further loss of forest cover in the watershed area. The findings of the study could help in developing effective strategies for future resource management and conservation, as well as for controlling land degradation in the watershed area. (author)

  1. Impacts of deforestation on water balance components of a watershed on the Brazilian East Coast

    Directory of Open Access Journals (Sweden)

    Donizete dos Reis Pereira

    2014-08-01

    Full Text Available The Brazilian East coast was intensely affected by deforestation, which drastically cut back the original biome. The possible impacts of this process on water resources are still unknown. The purpose of this study was an evaluation of the impacts of deforestation on the main water balance components of the Galo creek watershed, in the State of Espírito Santo, on the East coast of Brazil. Considering the real conditions of the watershed, the SWAT model was calibrated with data from 1997 to 2000 and validated for the period between 2001 and 2003. The calibration and validation processes were evaluated by the Nash-Sutcliffe efficiency coefficient and by the statistical parameters (determination coefficient, slope coefficient and F test of the regression model adjusted for estimated and measured flow data. After calibration and validation of the model, new simulations were carried out for three different land use scenarios: a scenario in compliance with the law (C1, assuming the preservation of PPAs (permanent preservation areas; an optimistic scenario (C2, which considers the watershed to be almost entirely covered by native vegetation; and a pessimistic scenario (C3, in which the watershed would be almost entirely covered by pasture. The scenarios C1, C2 and C3 represent a soil cover of native forest of 76, 97 and 0 %, respectively. The results were compared with the simulation, considering the real scenario (C0 with 54 % forest cover. The Nash-Sutcliffe coefficients were 0.65 and 0.70 for calibration and validation, respectively, indicating satisfactory results in the flow simulation. A mean reduction of 10 % of the native forest cover would cause a mean annual increase of approximately 11.5 mm in total runoff at the watershed outlet. Reforestation would ensure minimum flows in the dry period and regulate the maximum flow of the main watercourse of the watershed.

  2. Applying online WEPP to assess forest watershed hydrology

    Science.gov (United States)

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

    2011-01-01

    The U.S. Army Corps of Engineers (USACE) and the Great Lakes Commission are developing technologies and predictive tools to aid in watershed management with an ultimate goal of improving and preserving the water quality in the Great Lakes Basin. A new version of the online Water Erosion Prediction Project (WEPP) GIS interface has been developed to assist in evaluating...

  3. The economic benefits of vegetation in the upstream area of Ciliwung watershed

    Science.gov (United States)

    Saridewi, T. R.; Nazaruddin

    2018-04-01

    Ciliwung watershed has strategic values since its entire downstream area is located in the Special Administrative Region of Jakarta (DKI Jakarta), the capital of Indonesia. This causes forest and farmland areas are converted into open areas or built-up areas. The existence of these areas provides enormous environmental and economic benefits. Economic benefit values are very important to be considered in developing a policy development plan, but they have not been calculated yet. This study aims to determine the economic benefits provided by trees and other vegetation anddevelops a development policy that takes into account simultaneously ecological and economic aspects. The study is conducted in the upstream Ciliwung watershed, by using land cover patterns in 1989, 2000, 2010 and 2014, and employs GIS and CITY green analysis. The results show that conversion of forest and farmland areas reduces the ability of Ciliwung upstream watershed to store water. Therefore, its ability to reduce the flow of surface has been decreased. This creates a decrease in the cost savings of annual stormwater, from US 15,175,721 in 1989 to US 13,317,469 in 2014. The Environmental Services Payment Policy (PES) for upstream community groups managing the watershed has been considered as a fairly effective policy.

  4. Head-of-tide bottleneck of particulate material transport from watersheds to estuaries

    Science.gov (United States)

    Ensign, Scott H.; Noe, Gregory; Hupp, Cliff R.; Skalak, Katherine

    2015-01-01

    We measured rates of sediment, C, N, and P accumulation at four floodplain sites spanning the nontidal through oligohaline Choptank and Pocomoke Rivers, Maryland, USA. Ceramic tiles were used to collect sediment for a year and sediment cores were collected to derive decadal sedimentation rates using 137Cs. The results showed highest rates of short- and long-term sediment, C, N, and P accumulation occurred in tidal freshwater forests at the head of tide on the Choptank and the oligohaline marsh of the Pocomoke River, and lowest rates occurred in the downstream tidal freshwater forests in both rivers. Presumably, watershed material was mostly trapped at the head of tide, and estuarine material was trapped in oligohaline marshes. This hydrologic transport bottleneck at the head of tide stores most available watershed sediment, C, N, and P creating a sediment shadow in lower tidal freshwater forests potentially limiting their resilience to sea level rise.

  5. A CN-Based Ensembled Hydrological Model for Enhanced Watershed Runoff Prediction

    Directory of Open Access Journals (Sweden)

    Muhammad Ajmal

    2016-01-01

    Full Text Available A major structural inconsistency of the traditional curve number (CN model is its dependence on an unstable fixed initial abstraction, which normally results in sudden jumps in runoff estimation. Likewise, the lack of pre-storm soil moisture accounting (PSMA procedure is another inherent limitation of the model. To circumvent those problems, we used a variable initial abstraction after ensembling the traditional CN model and a French four-parameter (GR4J model to better quantify direct runoff from ungauged watersheds. To mimic the natural rainfall-runoff transformation at the watershed scale, our new parameterization designates intrinsic parameters and uses a simple structure. It exhibited more accurate and consistent results than earlier methods in evaluating data from 39 forest-dominated watersheds, both for small and large watersheds. In addition, based on different performance evaluation indicators, the runoff reproduction results show that the proposed model produced more consistent results for dry, normal, and wet watershed conditions than the other models used in this study.

  6. Water quality and mass transport in four watersheds in eastern Puerto Rico: Chapter E in Water quality and landscape processes of four watersheds in eastern Puerto Rico

    Science.gov (United States)

    Stallard, Robert F.; Murphy, Sheila F.; Murphy, Sheila F.; Stallard, Robert F.

    2012-01-01

    Water quality of four small watersheds in eastern Puerto Rico has been monitored since 1991 as part of the U.S. Geological Survey's Water, Energy, and Biogeochemical Budgets program. These watersheds represent a montane, humid-tropical environment and differ in geology and land cover. Two watersheds are located on granitic rocks, and two are located on volcaniclastic rock. For each bedrock type, one watershed is covered with mature rainforest in the Luquillo Mountains, and the other watershed is undergoing reforestation after being affected by agricultural practices typical of eastern Puerto Rico. A subwatershed of the Icacos watershed, the Guabá, was also monitored to examine scaling effects. The water quality of the rivers draining forest, in the Icacos and Guabá (granitic watersheds) and Mameyes (a volcaniclastic watershed), show little contamination by human activities. The water is well oxygenated and has a nearly neutral pH, and nutrient concentrations are low. Concentrations of nutrients in the disturbed watersheds, the Cayaguás (granitic rock) and Canóvanas (volcaniclastic rock), are greater than in the forested watersheds, indicating some inputs from human activities. High in-stream productivity in the Canóvanas watershed leads to occasional oxygen and calcite supersaturation and carbon dioxide undersaturation. Suspended sediment concentrations in all watersheds are low, except during major storms. Most dissolved constituents derived from bedrock weathering or atmospheric deposition (including sodium, magnesium, calcium, silica, alkalinity, and chloride) decrease in concentration with increasing runoff, reflecting dilution from increased proportions of overland or near-surface flow. Strongly bioactive constituents (dissolved organic carbon, potassium, nitrate, ammonium ion, and phosphate) commonly display increasing concentration with increasing runoff, regardless of their ultimate origin (bedrock or atmosphere). The concentrations of many of the

  7. Exploring interactions between payment for hydrologic service policies, landowner decisions, and ecohydrology in a Mexican cloud forest watershed: Is there a disconnect between the policy and the resource?

    Science.gov (United States)

    Asbjornsen, H.; Geissert, D.; Gomez-Tagle, A.; Holwerda, F.; Manson, R.; Perez-Maqueo, O.; Munoz-Villers, L.; Scullion, J.

    2013-05-01

    Payment for hydrologic service (PHS) programs are increasingly being used as a means to incentivize watershed protection by compensating upstream 'water producers' with payments made by downstream 'water consumers'. However, the effectiveness of PHS programs in achieving their target goals is often poorly understood. Here, we draw from insights obtained from socioeconomic and ecohydrological research in Veracruz, Mexico to explore interactions between PHS policies, landowner decisions, and hydrologic services. GIS analysis of land-cover changes during 2003-2009 combined with interviews of PHS participants indicated that despite lower deforestation rates on properties receiving PES payments, other factors were likely to have a greater influence on land use decisions than PHS payments per se, including opportunity costs and personal conservation ethic. The interviews also highlighted a general lack of trust and cooperation between the citizen participants and government administrators, which was reflected in the relatively low level of knowledge of the PHS programs' regulations and goals, the role of forests in protecting water resources, and a low level of co-financing by the private sector. An important premise of PHS programs is that protecting existing forest cover (and planting trees) will enhance water supply, especially in upland cloud forests that are due to their perceived role as water producers. Measurements of climate, steamflow, canopy fog interception, plant transpiration, soil water dynamics, and hydrologic flow paths were collected over a 3-year period to assess stand water balance and streamflow response under four different land covers: mature cloud forest, pasture, regenerating cloud forest, pine reforestation. Results suggested relatively minor additional inputs of fog to increasing streamflow in cloud forest watersheds, while conversion of forest to pasture did not markedly decrease dry season flows, but did increase annual flows due to lower

  8. Disentangling the Long-term Effects of Climate Change and Forest Structure and Species Composition on Streamflow Across the Eastern US

    Science.gov (United States)

    Caldwell, P.; Elliott, K.; Hartsell, A.; Miniat, C.

    2016-12-01

    Climate change and disturbances are threatening the ability of forested watersheds to provide the clean, reliable, and abundant fresh water necessary to support aquatic ecosystems and a growing human population. Forested watersheds in the eastern US have undergone significant change over the 20th century due to natural and introduced disturbances and a legacy of land use. We hypothesize that changes in forest age and species composition (i.e., forest change) associated with these disturbances may have altered forest water use and thus streamflow (Q) due to inherent differences in transpiration among species and forest ages. To test this hypothesis, we quantified changes in Q from 1960 to 2012 in 202 US Geological Survey forested reference watersheds across the eastern US, and separated the effect of changes in climate from forest change using Auto-Regressive Integrated Moving Average (ARIMA) time series modeling. We linked changes in Q to forest disturbance, forest ages and species composition using the Landsat-based North American Forest Dynamics dataset and plot-level USDA Forest Service Forest Inventory and Analysis (FIA) data. We found that 172 of the 202 sites (85%) exhibited changes in Q not accounted for by climate that we attributed to forest change and/or land use change. Among these, 76 (44%) had declining Q due to forest change (mostly in the southeastern US) while 96 (56%) had increasing Q (mostly in the mid-Atlantic and northeastern US). Across the 172 sites with forest-related changes in Q, 34% had at least 10% of the watershed area disturbed at least once from 1986-2010. In a case study of three watersheds, FIA data indicated that changes in forest structure and species composition explained observed changes in Q beyond climate effects. Our results suggest that forest-related changes in Q may have significant implications for water supply in the region and may inform forest management strategies to mitigate climate change impacts on water resources.

  9. Impacts of forest management on runoff and erosion

    Science.gov (United States)

    William J. Elliot; Brandon D. Glaza

    2009-01-01

    In a parallel study, ten small watersheds (about 5 ha) were installed in the Priest River Experimental Forest (PREF) in northern Idaho, and another ten were installed in the Boise Basin Experimental Forest (BBEF) in central Idaho. The long-term objective of the study is to compare the effects of different forest management activities on runoff and...

  10. Assessing Forest Carbon Response to Climate Change and Disturbances Using Long-term Hydro-climatic Observations and Simulations

    Science.gov (United States)

    Trettin, C.; Dai, Z.; Amatya, D. M.

    2014-12-01

    Long-term climatic and hydrologic observations on the Santee Experimental Forest in the lower coastal plain of South Carolina were used to estimate long-term changes in hydrology and forest carbon dynamics for a pair of first-order watersheds. Over 70 years of climate data indicated that warming in this forest area in the last decades was faster than the global mean; 35+ years of hydrologic records showed that forest ecosystem succession three years following Hurricane Hugo caused a substantial change in the ratio of runoff to precipitation. The change in this relationship between the paired watersheds was attributed to altered evapotranspiration processes caused by greater abundance of pine in the treatment watershed and regeneration of the mixed hardwood-pine forest on the reference watershed. The long-term records and anomalous observations are highly valuable for reliable calibration and validation of hydrological and biogeochemical models capturing the effects of climate variability. We applied the hydrological model MIKESHE that showed that runoff and water table level are sensitive to global warming, and that the sustained warming trends can be expected to decrease stream discharge and lower the mean water table depth. The spatially-explicit biogeochemical model Forest-DNDC, validated using biomass measurements from the watersheds, was used to assess carbon dynamics in response to high resolution hydrologic observation data and simulation results. The simulations showed that the long-term spatiotemporal carbon dynamics, including biomass and fluxes of soil carbon dioxide and methane were highly regulated by disturbance regimes, climatic conditions and water table depth. The utility of linked-modeling framework demonstrated here to assess biogeochemical responses at the watershed scale suggests applications for assessing the consequences of climate change within an urbanizing forested landscape. The approach may also be applicable for validating large

  11. Nitrogen Saturation in Highly Retentive Watersheds?

    Science.gov (United States)

    Daley, M. L.; McDowell, W. H.

    2009-12-01

    Watershed managers are often concerned with minimizing the amount of N delivered to N-limited estuaries and coastal zones. A major concern is that watersheds might reach N saturation, in which N delivered to coastal zones increases due to declines in the efficiency of N retention despite constant or even reduced N inputs. We have quantified long-term changes in N inputs (atmospheric deposition, imported food and agricultural fertilizers), outputs (N concentration and export) and retention in the urbanizing Lamprey River watershed in coastal NH. Overall, the Lamprey watershed is 70% forested, receives about 13.5 kg N/ha/yr and has a high rate of annual N retention (85%). Atmospheric deposition (8.7 kg/ha/yr) is the largest N input to the watershed. Of the 2.2 kg N/ha/yr exported in the Lamprey River, dissolved organic N (DON) is the dominant form (50% of total) and it varies spatially throughout the watershed with wetland cover. Nitrate accounts for 30% of the N exported, shows a statistically significant increase from 1999 to 2009, and its spatial variability in both concentration and export is related to human population density. In sub-basins throughout the Lamprey, inorganic N retention is high (85-99%), but the efficiency of N retention declines sharply with increased human population density and associated anthropogenic N inputs. N assimilation in the vegetation, denitrification to the atmosphere and storage in the groundwater pool could all be important contributors to the current high rates of N retention. The temporal and spatial patterns that we have observed in nitrate concentration and export are driven by increases in N inputs and impervious surfaces over time, but the declining efficiency of N retention suggests that the watershed may also be reaching N saturation. The downstream receiving estuary, Great Bay, already suffers from low dissolved oxygen levels and eelgrass loss in part due to N loading from the Lamprey watershed. Targeting and reducing

  12. Improved daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay Watershed

    International Nuclear Information System (INIS)

    Grimm, J.W.; Lynch, J.A.

    2005-01-01

    Daily precipitation nitrate and ammonium concentration models were developed for the Chesapeake Bay Watershed (USA) using a linear least-squares regression approach and precipitation chemistry data from 29 National Atmospheric Deposition Program/National Trends Network (NADP/NTN) sites. Only weekly samples that comprised a single precipitation event were used in model development. The most significant variables in both ammonium and nitrate models included: precipitation volume, the number of days since the last event, a measure of seasonality, latitude, and the proportion of land within 8 km covered by forest or devoted to industry and transportation. Additional variables included in the nitrate model were the proportion of land within 0.8 km covered by water and/or forest. Local and regional ammonia and nitrogen oxide emissions were not as well correlated as land cover. Modeled concentrations compared very well with event chemistry data collected at six NADP/AirMoN sites within the Chesapeake Bay Watershed. Wet deposition estimates were also consistent with observed deposition at selected sites. Accurately describing the spatial distribution of precipitation volume throughout the watershed is important in providing critical estimates of wet-fall deposition of ammonium and nitrate. - A linear least-squares regression approach was used to develop daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay Watershed

  13. Land suitability assessment on a watershed of Loess Plateau using the analytic hierarchy process.

    Science.gov (United States)

    Yi, Xiaobo; Wang, Li

    2013-01-01

    In order to reduce soil erosion and desertification, the Sloping Land Conversion Program has been conducted in China for more than 15 years, and large areas of farmland have been converted to forest and grassland. However, this large-scale vegetation-restoration project has faced some key problems (e.g. soil drying) that have limited the successful development of the current ecological-recovery policy. Therefore, it is necessary to know about the land use, vegetation, and soil, and their inter-relationships in order to identify the suitability of vegetation restoration. This study was conducted at the watershed level in the ecologically vulnerable region of the Loess Plateau, to evaluate the land suitability using the analytic hierarchy process (AHP). The results showed that (1) the area unsuitable for crops accounted for 73.3% of the watershed, and the main factors restricting cropland development were soil physical properties and soil nutrients; (2) the area suitable for grassland was about 86.7% of the watershed, with the remaining 13.3% being unsuitable; (3) an area of 3.95 km(2), accounting for 66.7% of the watershed, was unsuitable for forest. Overall, the grassland was found to be the most suitable land-use to support the aims of the Sloping Land Conversion Program in the Liudaogou watershed. Under the constraints of soil water shortage and nutrient deficits, crops and forests were considered to be inappropriate land uses in the study area, especially on sloping land. When selecting species for re-vegetation, non-native grass species with high water requirements should be avoided so as to guarantee the sustainable development of grassland and effective ecological functioning. Our study provides local land managers and farmers with valuable information about the inappropriateness of growing trees in the study area along with some information on species selection for planting in the semi-arid area of the Loess Plateau.

  14. Bank-derived material dominates fluvial sediment in a suburban Chesapeake Bay watershed

    Science.gov (United States)

    Cashman, M. J.; Gellis, A.; Gorman-Sanisaca, L.; Noe, G. B.; Cogliandro, V.; Baker, A.

    2017-12-01

    Excess fine sediment is a leading cause of ecological degradation within the Chesapeake Bay watershed. The Piedmont physiographic province, which includes parts of the Washington, D.C. metro area, has the highest sediment yields in the Chesapeake Bay. In order to effectively employ sediment mitigation measures, it is necessary to identify and quantify the contributions of sediments sources within rapidly urbanizing areas in the Piedmont. This sediment fingerprinting study examines the inputs of various sediment sources to Upper Difficult Run (14.2 km2; 22.6% impervious surface), an urbanized watershed in Fairfax County, Virginia. A source sediment library was constructed from collections of stream bank material, forest soils, and road dust from across the watershed. Target fluvial sediments were collected from fine channel margin deposits and from suspended sediment using an autosampler during 16 storm events from 2008 - 2012. Apportionment of the target samples to the source sediments was performed using Sed_SAT, a publically available toolkit for sediment fingerprinting. Bed sediment was found to be dominated by stream bank sources (mean: 96%), with minor contributions from forest (4%) and no detectable contribution from roads (0%). Suspended fine sediments were also found to predominantly originate from stream bank sources (SSC-weighted mean: 91%), with minor contributions from roads (8%), and negligible contributions from forests (1%). Stream bank sources dominated at all discharges, with the greatest contributions from overland sources found only at low discharges. On the rising limb of the hydrograph and at peak flow, sediment concentrations increased due to increasing contributions of bank material rather than surface erosion caused by overland flow. Results demonstrate that stream bank erosion is responsible for the vast majority of fine sediment occurring in this suburban basin of the Chesapeake Bay watershed. This is likely a consequence of storm

  15. Quasi-Empirical and Spatio-Temporal Vulnerability Modeling of Environmental Risks Posed to a Watershed

    Science.gov (United States)

    Rozario, Papia Faustina

    Water quality assessment is crucial in investigating impairment within agricultural watersheds. Seasonal and spatial variations on land can directly affect the adjoining riverine systems. Studies have revealed that agricultural activities are often major contributors to altering water quality of surface waters. A common means of addressing this issue is through the establishment and monitoring the health of riparian vegetation buffers along those areas of stream channels that would be most susceptible to the threat. Remote sensing and Geographic Information Systems (GIS) offer a means by which impaired areas can be identified, so that subsequent action toward the establishment of riparian zones can be taken. Modeling the size and rate of land use and land cover (LULC) change is an effective method of projecting localized impairment. This study presents an integrated model utilizing Analytical Hierarchical Process (AHP), Markov Chain Monte Carlo (MCMC) simulations, and geospatial analyses to address areas of impairment within the Pipestem Creek watershed, a part of the Missouri Watershed James Sub-region of North Dakota, USA. The rate and direction of LULC change was analyzed through this model and its impact on the ambient water and soil quality was studied. Tasseled Cap Greenness Index (TCGI) was used to determine the loss of forested land within the watershed from 1976 to 2015. Research results validated temporal and spatial relations of LULC dynamics to nutrient concentrations especially those that would be noted at the mouth of the watershed. It was found that the levels of Total Dissolved Solids (TDS) were much higher for the years 2014 to 2016 with a discernible increased localized alkalizing effect within the watershed. Fallow areas were seen to produce significant amounts of sediment loads from the sub-watershed. LULC distribution from 2007 to 2015 show that it is possible to project future land use change patterns. About 89.90% likelihood of increment in

  16. Acid deposition and water use efficiency in Appalachian forests

    Science.gov (United States)

    Malcomb, J.

    2017-12-01

    Multiple studies have reported increases in forest water use efficiency in recent decades, but the drivers of these trends remain uncertain. While acid deposition has profoundly altered the biogeochemistry of Appalachian forests in the past century, its impacts on forest water use efficiency have been largely overlooked. Plant ecophysiology literature suggests that plants up-regulate transpiration in response to soil nutrient limitation in order to maintain sufficient mass flow of nutrients. To test the impacts of acid deposition on forest eco-hydrology in central Appalachia, we integrated dendrochronological techniques, including tree ring δ13C analysis, with catchment water balance data from the Fernow Experimental Forest in West Virginia. Tree cores from four species were collected in Fernow Watershed 3, which has received experimental ammonium sulfate additions since 1989, and Watershed 7, an adjacent control catchment. Initial results suggest that acidification treatments have not significantly influenced tree productivity compared to a control watershed, but the effect varies by species, with tulip poplar showing greatest sensitivity to acidification. Climatic water balance, defined as the difference between growing season precipitation and evapotranspiration, is significantly related to annual tree ring growth, suggesting that climate may be driving tree growth trends in chronically acidified Appalachian forests. Tree ring 13C analysis from Fernow cores is underway and these data will be integrated with catchment hydrology data from five other sites in central Appalachia and the U.S. Northeast, representing a range of forest types, soil base saturations, and acid deposition histories. This work will advance understanding of how climate and acid deposition interact to influence forest productivity and water use efficiency, and improve our ability to model carbon and water cycling in forested ecosystems impacted by acid deposition.

  17. Estimating erosion in a riverine watershed: Bayou Liberty-Tchefuncta River in Louisiana.

    Science.gov (United States)

    Martin, August; Gunter, James T; Regens, James L

    2003-01-01

    GOAL, SCOPE, BACKGROUND: Sheet erosion from agricultural, forest and urban lands may increase stream sediment loads as well as transport other pollutants that adversely affect water quality, reduce agricultural and forest production, and increase infrastructure maintenance costs. This study uses spatial analysis techniques and a numerical modeling approach to predict areas with the greatest sheet erosion potential given different soils disturbance scenarios. A Geographic Information System (GIS) and the Universal Soil Loss Equation (USLE) were used to estimate sheet erosion from 0.64 ha parcels of land within the watershed. The Soil Survey of St. Tammany Parish, Louisiana was digitized, required soil attributes entered into the GIS database, and slope factors determined for each 80 x 80 meter parcel in the watershed. The GIS/USLE model used series-specific erosion K factors, a rainfall factor of 89, and a GIS database of scenario-driven cropping and erosion control practice factors to estimate potential soil loss due to sheet erosion. A general trend of increased potential sheet erosion occurred for all land use categories (urban, agriculture/grasslands, forests) as soil disturbance increases from cropping, logging and construction activities. Modeling indicated that rapidly growing urban areas have the greatest potential for sheet erosion. Evergreen and mixed forests (production forest) had lower sheet erosion potentials; with deciduous forests (mostly riparian) having the least sheet erosion potential. Erosion estimates from construction activities may be overestimated because of the value chosen for the erosion control practice factor. This study illustrates the ease with which GIS can be integrated with the Universal Soil Loss Equation to identify areas with high sheet erosion potential for large scale management and policy decision making. The GIS/USLE modeling approach used in this study offers a quick and inexpensive tool for estimating sheet erosion within

  18. Fourth annual Walker Branch Watershed research symposium: Program and abstracts

    International Nuclear Information System (INIS)

    1993-03-01

    The methods and concepts of watershed research, originally applied in an experimental or monitoring mode to relatively small catchments, are increasingly being used at larger scales and for specific applied problems. Research at Oak Ridge National Laboratory, the Tennessee Valley Authority, the US Forest Service, and other agencies and institutions participating in this symposium reflects research over a broad range of spatial scales that is being integrated through large-scale experiments along with computer modeling and graphical interfaces. These research projects address the basic atmospheric, geophysical, biogeochemical, and biological processes that regulate the responses of forested ecosystems to natural environmental variation and anthropogenic stresses. This symposium highlights the use of large-scale ecosystem experiments to address environmental issues of global concern. These experiments provide the only effective way to test models of ecosystem response that are based on the current state of knowledge of hydrology, biogeochemistry, plant physiology, and other ecosystem processes. Major environmental problems that are being addressed include acidic deposition and nitrogen loading (Bear Brook Watershed, Maine; and the Girdsjoen Covered Catchment, Sweden); climate warming (Soil Warming Experiment, Maine); and altered rainfall amounts (Savannah River Loblolly Pine Soil Water Manipulation and the Walker Branch Watershed Throughfall Displacement Experiment)

  19. Variable Width Riparian Model Enhances Landscape and Watershed Condition

    Science.gov (United States)

    Abood, S. A.; Spencer, L.

    2017-12-01

    Riparian areas are ecotones that represent about 1% of USFS administered landscape and contribute to numerous valuable ecosystem functions such as wildlife habitat, stream water quality and flows, bank stability and protection against erosion, and values related to diversity, aesthetics and recreation. Riparian zones capture the transitional area between terrestrial and aquatic ecosystems with specific vegetation and soil characteristics which provide critical values/functions and are very responsive to changes in land management activities and uses. Two staff areas at the US Forest Service have coordinated on a two phase project to support the National Forests in their planning revision efforts and to address rangeland riparian business needs at the Forest Plan and Allotment Management Plan levels. The first part of the project will include a national fine scale (USGS HUC-12 digits watersheds) inventory of riparian areas on National Forest Service lands in western United States with riparian land cover, utilizing GIS capabilities and open source geospatial data. The second part of the project will include the application of riparian land cover change and assessment based on selected indicators to assess and monitor riparian areas on annual/5-year cycle basis.This approach recognizes the dynamic and transitional nature of riparian areas by accounting for hydrologic, geomorphic and vegetation data as inputs into the delineation process. The results suggest that incorporating functional variable width riparian mapping within watershed management planning can improve riparian protection and restoration. The application of Riparian Buffer Delineation Model (RBDM) approach can provide the agency Watershed Condition Framework (WCF) with observed riparian area condition on an annual basis and on multiple scales. The use of this model to map moderate to low gradient systems of sufficient width in conjunction with an understanding of the influence of distinctive landscape

  20. 78 FR 20613 - Ochoco National Forest, Paulina Ranger District; Oregon; Wolf Creek Vegetation and Fuels...

    Science.gov (United States)

    2013-04-05

    ... 2012 and documented in the Wolf Creek Watershed Analysis. The watershed analysis determined that... includes National Forest system lands within the Lower Beavercreek watershed. The alternatives that will be... analysis and decision making process so interested and affected people may participate and contribute to...

  1. The Hidden Watershed's Journals: the Informational Characteristics of Biomarkers in Sedimentary Deposits

    Science.gov (United States)

    Guerrero, F. J.; Hatten, J. A.

    2014-12-01

    The historical reconstruction of past environmental changes in watersheds is essential to understand watershed response to disturbances and how those diturbances could affect the provision of valuable goods like water. That reconstruction requires the interpretation of natural records, mainly associated to sedimentary deposits that store detailed information in the form of specific biogenic molecules (i.e. biomarkers). In forested watersheds terrestrial vegetation is an important source of biomarkers like those associated to Lignin, a complex organic polymer used by plants to provide physical support in its tissues. Through litter inputs Lignin is deposited in soils and then is transported to sedimentary environments by rivers (e.g. floodplains, lake bottoms), serving as a source of information about vegetation changes in watersheds. In spite of the critical character of the information extracted from biomarkers in sedimentary records, the very concept of information is still used in a metaphorical sense, even though it was formally defined more than 60 years ago and has been applied extensively in ecology (e.g. Shannon's diversity index). Furthermore, sophisticated techniques are being used to deliver more complex molecular data that require examination and validation as indicators for watershed historical reconstructions. My research aims to explore the applicability of some information metrics (i.e. diversity indices, information coefficients) to a diverse molecular set derived from the chemical depolymerization of lignin deposited in floodplains and lake sediments in different basins. This approach attempts to assess the informational characteristics of Lignin as an indicator of natural/human-induced perturbations in forested watersheds. The formal assessment of the informational characteristics of natural records could have a profound impact not only in our methodological approaches but also in our philosophical view about information and communication in

  2. Variability in estimated runoff in a forested area based on different cartographic data sources

    Energy Technology Data Exchange (ETDEWEB)

    Fragoso, L.; Quirós, E.; Durán-Barroso, P.

    2017-11-01

    Aim of study: The goal of this study is to analyse variations in curve number (CN) values produced by different cartographic data sources in a forested watershed, and determine which of them best fit with measured runoff volumes. Area of study: A forested watershed located in western Spain. Material and methods: Four digital cartographic data sources were used to determine the runoff CN in the watershed. Main results: None of the cartographic sources provided all the information necessary to determine properly the CN values. Our proposed methodology, focused on the tree canopy cover, improves the achieved results. Research highlights: The estimation of the CN value in forested areas should be attained as a function of tree canopy cover and new calibrated tables should be implemented in a local scale.

  3. Wind River Watershed Restoration Project, Segment II, 2000-2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Bair, Brian; Olegario, Anthony; Powers, Paul

    2002-06-01

    This document represents work conducted as part of the Wind River Watershed Restoration Project during its second year of funding through the Bonneville Power Administration (BPA). The project is a comprehensive effort involving public and private entities seeking to restore water quality and fishery resources in the basin through cooperative actions. Project elements include coordination, watershed assessment, restoration, monitoring, and education. Entities involved with implementing project components are the Underwood Conservation District (UCD), USDA Forest Service (USFS), U.S. Geological Survey - Columbia River Research Lab (USGS-CRRL), and WA Department of Fish & Wildlife (WDFW).

  4. Modelling land use/cover changes with markov-cellular automata in Komering Watershed, South Sumatera

    Science.gov (United States)

    Kusratmoko, E.; Albertus, S. D. Y.; Supriatna

    2017-01-01

    This research has a purpose to study and develop a model that can representing and simulating spatial distribution pattern of land use change in Komering watershed. The Komering watershed is one of nine sub Musi river basin and is located in the southern part of Sumatra island that has an area of 8060,62 km2. Land use change simulations, achieved through Markov-cellular automata (CA) methodologies. Slope, elevation, distance from road, distance from river, distance from capital sub-district, distance from settlement area area were driving factors that used in this research. Land use prediction result in 2030 also shows decrease of forest acreage up to -3.37%, agricultural land decreased up to -2.13%, and open land decreased up to -0.13%. On the other hand settlement area increased up to 0.07%, and plantation land increased up to 5.56%. Based on the predictive result, land use unconformity percentage to RTRW in Komering watershed is 18.62 % and land use conformity is 58.27%. Based on the results of the scenario, where forest in protected areas and agriculture land are maintained, shows increase the land use conformity amounted to 60.41 % and reduce unconformity that occur in Komering watershed to 17.23 %.

  5. Leaf Area Index (LAI) in different type of agroforestry systems based on hemispherical photographs in Cidanau Watershed

    Science.gov (United States)

    Nur Khairiah, Rahmi; Setiawan, Yudi; Budi Prasetyo, Lilik; Ayu Permatasari, Prita

    2017-01-01

    Ecological functions of agroforestry systems have perceived benefit to people around Cidanau Watershed, especially in the protection of water quality. The main causes of the problems encountered in the Cidanau Watershed are associated with the human factors, especially encroachment and conversion of forest into farmland. The encroachment has made most forest in Cidanau Watershed become bare land. To preserve the ecological function of agroforestry systems in Cidanau Watershed, monitoring of the condition of the vegetation canopy in agroforestry systems is really needed. High intensity thinning of crown density due to deforestation can change stand leaf area index dramatically. By knowing LAI, we can assess the condition of the vegetation canopy in agroforestry systems. LAI in this research was obtained from Hemispherical Photographs analysis using the threshold method in HemiView Canopy Analysis Software. Our research results indicate that there are six types of agroforestry in Cidanau Watershed i.e. Sengon Agroforestry, Clove Agroforestry, Melinjo Agroforestry, Chocolate Agroforestry, Coffee Agroforestry, and Complex Agroforestry. Several factors potentially contribute to variations in the value of LAI in different types of agroforestry. The simple assumptions about differences ranges of LAI values on six types of agroforestry is closely related to leaf area and plant population density.

  6. Water Quality in Micro-watersheds Under Different Land Uses in the Municipality of Alegre, Espírito Santo

    Directory of Open Access Journals (Sweden)

    Milena Scaramussa Pastro

    2018-05-01

    Full Text Available ABSTRACT The present study aimed to evaluate water quality attributes in micro-watersheds under different soil uses. Therefore, four micro-watersheds under the following vegetation cover were selected: pasture, primary forest reforestation, forest, and coffee plantation. Surface and underground water sampling was performed bimonthly between February and December 2014, where thermotolerant coliforms, dissolved oxygen, total nitrogen, phosphorus, turbidity, temperature, pH, biochemical demand for oxygen and total solids were analyzed. Descriptive analyses of each variable were performed during dry and rainy periods, and the values were compared with the normative standards established by Brazilian legislation. Water Quality Indices (WQIs were also calculated for each collection site. All sites presented some type of nonconformity with human consumption standards. The highest WQI values were found in the forest area micro-basin, followed by the coffee plantation and pasture area micro-basins, highlighting the importance of forested areas for water quality.

  7. Characterizing Ecosystem and Watershed Response to Atmospheric Loading at the Urban Fringe

    Science.gov (United States)

    Curto, V.; Lopez, S.; Hogue, T.; Rademacher, L.

    2006-12-01

    The southern California region, although highly urbanized and densely populated, is also characterized by steep mountain ranges with extensive forests and diverse ecosystems. Growing population pressure in the region has forced continuing development at the urban fringe. The large mountain systems situated on the windward side of the Los Angeles basin experience high atmospheric nitrogen deposition rates from various urban pollutants. Arroyo Seco, a watershed located on the eastern edge of the Los Angeles basin, is no exception to this trend. The present study uses hydrologic and geochemical data to assess current watershed dynamics and ecosystem responses to the impacts of regional urbanization. The Arroyo Seco stream runs through a deeply incised canyon originating in the San Gabriel Mountains and draining into the Los Angeles River. The current riparian habitat, which comprises only 15 percent of the total land cover within the watershed, contains over 705 species of plants and animals. We focused our studies on the upper reaches of the basin (~18 square miles), which remains undeveloped and consists primarily of chaparral and evergreen forests. This portion of the watershed has an average watershed slope of approximately 6 percent and relatively porous soils. However, estimated runoff ratio from the existing USGS gage and local precipitation gages indicates fairly high runoff (discharge/precipitation ratio of 0.29). Weekly stream samples have been collected over a several year period and analyzed for standard geochemical constituents and stable isotopes to assess deposition impacts on ecosystem function and overall watershed behavior. Stable isotopes of water measured in the weekly Arroyo Seco stream samples deviate from the global meteoric water line (GMWL), particularly during summer months. High evaporative rates in the summer may be responsible for the distinct summer pattern and overall deviation from the GMWL of stream isotope values. An

  8. Forest blowdown and lake acidification

    International Nuclear Information System (INIS)

    Dobson, J.E.; Rush, R.M.; Peplies, R.W.

    1990-01-01

    The authors examine the role of forest blowdown in lake acidification. The approach combines geographic information systems (GIS) and digital remote sensing with traditional field methods. The methods of analysis consist of direct observation, interpretation of satellite imagery and aerial photographs, and statistical comparison of two geographical distributions-one representing forest blow-down and another representing lake chemistry. Spatial and temporal associations between surface water pH and landscape disturbance are strong and consistent in the Adirondack Mountains of New York. In 43 Adirondack Mountain watersheds, lake pH is associated with the percentage of the watershed area blown down and with hydrogen ion deposition (Spearman rank correlation coefficients of -0.67 and -0.73, respectively). Evidence of a temporal association is found at Big Moose Lake and Jerseyfield Lake in New York and the Lygners Vider Plateau of Sweden. They conclude that forest blowdown facilities the acidification of some lakes by altering hydrologic pathways so that waters (previously acidified by acid deposition and/or other sources) do not experience the neutralization normally available through contact with subsurface soils and bedrock. Increased pipeflow is suggested as a mechanism that may link the biogeochemical impacts of forest blowdown to lake chemistry

  9. Evaluation of landscape change in the Vidoca Stream Watershed, São José dos Campos, SP, Brazil

    Directory of Open Access Journals (Sweden)

    Ademir Fernando Morelli

    2007-12-01

    Full Text Available Hydrographic basins in urban areas frequently undergo drastic landscape changes. This work analyzed the landscape transformation of Vidoca Stream Watershed in the period from 1500 to 2003. Based on Remote Sensing and GIS techniques it was found that: a Between 1500 and 1953 natural vegetation classes which included Alluvial Semi-decidual Seasonal Forest, Mountainous Semi-decidual Seasonal Forest and Open Arboreal Savannah changed to anthropic fields and grasslands; b From 1954 to 1985, just before the massive urban occupation of the area, there was a short period of regeneration of the Alluvial Semi-decidual Seasonal Forest above the Carvalho Pinto Highway; later on, the grasslands changed to anthropic fields; c From 1986 to 1997, a fast urbanization process occurred and resulted in the replacement of the grassland and anthropic fields by urban constructions; d From 1998 to 2003, with the consolidation of the urbanization process, the urban occupation reached the boundaries of the plateau and the lowlands of the watershed, resulting in soil impermeabilization. The results of this research indicated that the urbanization process was not controlled in spite of restricted legislation and environmental degradation occurred in this studied watershed along of the study period.

  10. Third annual Walker Branch watershed research symposium: Programs and abstracts

    International Nuclear Information System (INIS)

    1992-03-01

    The methods and concepts of watershed research, originally applied in an experimental or monitoring mode to relatively small catchments, are increasingly being used at larger scales and for specific applied problems. Research at Oak Ridge National Laboratory, the Tennessee Valley Authority, the US Forest Service, and other agencies and institutions participating in this symposium reflects research over a broad range of spatial scales. These research projects address the basic atmospheric, geophysical, biogeochemical, and biological processes that regulate the responses of forested ecosystems to natural environmental variation and anthropogenic stresses. Regional and global issues addressed by presentations include emissions of carbon dioxide, methane, and other hydrocarbons; deposition of sulfate, nitrate, and mercury; land-use changes; biological diversity; droughts; and water quality. The Department of Energy's local research site, Walker Branch Watershed, is a long-term ecosystem research project initiated on the Oak Ridge Reservation in 1967. Walker Branch provides a well-characterized site where many of these methods can be tested and applied.In addition, other large-scale experiments represented in this symposium include experiments on the effects of clearcutting and burning on forest structure and productivity associated with Coweeta Hydrologic Laboratory, and whole-tree ozone exposure chambers constructed by TVA and ORNL researchers

  11. Coupling of Water and Carbon Cycles in Boreal Ecosystems at Watershed and National Scales

    Science.gov (United States)

    Chen, J. M.; Ju, W.; Govind, A.; Sonnentag, O.

    2009-05-01

    The boreal landscapes is relatively flat giving the impression of spatial homogeneity. However, glacial activities have left distinct fingerprints on the vegetation distribution on moderately rolling terrains over the boreal landscape. Upland or lowland forests types or wetlands having various degrees of hydrological connectivitiy to the surrounding terrain are typical of the boreal landscape. The nature of the terrain creates unique hydrological conditions affecting the local-scale ecophysiological and biogeochemical processes. As part of the Canadian Carbon Program, we investigated the importance of lateral water redistribution through surface and subsurface flows in the spatial distribution of the vertical fluxes of water and carbon. A spatially explicit hydroecological model (BEPS-TerrainLab) has been developed and tested in forested and wetland watersheds . Remotely sensed vegetation parameters along with other spatial datasets are used to run this model, and tower flux data are used for partial validation. It is demonstrated in both forest and wetland watersheds that ignoring the lateral water redistribution over the landscape, commonly done in 1-dimensional bucket models, can cause considerable biases in the vertical carbon and water flux estimation, in addition to the distortion of the spatial patterns of these fluxes. The biases in the carbon flux are considerably larger than those in the water flux. The significance of these findings in national carbon budget estimation is demonstrated by separate modeling of 2015 watersheds over the Canadian landmass.

  12. Predicting the impact of land management decisions on overland flow generation: Implications for cesium migration in forested Fukushima watersheds

    Science.gov (United States)

    Siirila-Woodburn, Erica R.; Steefel, Carl I.; Williams, Kenneth H.; Birkholzer, Jens T.

    2018-03-01

    The effects of land use and land cover (LULC) change on environmental systems across the land surface's "critical zone" are highly uncertain, often making prediction and risk management decision difficult. In a series of numerical experiments with an integrated hydrologic model, overland flow generation is quantified for both present day and forest thinning scenarios. A typhoon storm event in a watershed near the Fukushima Dai-ichi Nuclear Power Plant is used as an example application in which the interplay between LULC change and overland flow generation is important given that sediment-bound radionuclides may cause secondary contamination via surface water transport. Results illustrate the nonlinearity of the integrated system spanning from the deep groundwater to the atmosphere, and provide quantitative tools when determining the tradeoffs of different risk-mitigation strategies.

  13. Factors Affecting Source-Water Quality after Disturbance of Forests by Wildfire

    Science.gov (United States)

    Murphy, S. F.; Martin, D. A.; McCleskey, R. B.; Writer, J. H.

    2015-12-01

    Forests yield high-quality water supplies to communities throughout the world, in part because forest cover reduces flooding and the consequent transport of suspended and dissolved constituents to surface water. Disturbance by wildfire reduces or eliminates forest cover, leaving watersheds susceptible to increased surface runoff during storms and reduced ability to retain contaminants. We assessed water-quality response to hydrologic events for three years after a wildfire in the Fourmile Creek Watershed, near Boulder, Colorado, and found that hydrologic and geochemical responses downstream of a burned area were primarily driven by small, brief convective storms that had relatively high, but not unusual, rainfall intensity. Total suspended sediment, dissolved organic carbon, nitrate, and manganese concentrations were 10-156 times higher downstream of a burned area compared to upstream, and water quality was sufficiently impaired to pose water-treatment concerns. The response in both concentration and yield of water-quality constituents differed depending on source availability and dominant watershed processes controlling the constituent. For example, while all constituent concentrations were highest during storm events, annual sediment yields downstream of the burned area were controlled by storm events and subsequent mobilization, whereas dissolved organic carbon yields were more dependent on spring runoff from upstream areas. The watershed response was affected by a legacy of historical disturbance: the watershed had been recovering from extensive disturbance by mining, railroad and road development, logging, and fires in the late 19th and early 20th centuries, and we observed extensive erosion of mine waste in response to these summer storms. Therefore, both storm characteristics and historical disturbance in a burned watershed must be considered when evaluating the role of wildfire on water quality.

  14. Relation of watershed setting and stream nutrient yields at selected sites in central and eastern North Carolina, 1997-2008

    Science.gov (United States)

    Harden, Stephen L.; Cuffney, Thomas F.; Terziotti, Silvia; Kolb, Katharine R.

    2013-01-01

    ) were excluded from the regression tree analyses (Models 2–4), the percentage of forested land in the watersheds was identified as the primary environmental variable influencing stream yields for both total N and total P. Models 2, 3 and 4 did not identify any watershed environmental variables that could adequately explain the observed variability in the nitrate yields among the set of sites examined by each of these models. The results for Models 2, 3, and 4 indicated that watersheds with higher percentages of forested land had lower annual total N and total P yields compared to watersheds with lower percentages of forested land, which had higher median annual total N and total P yields. Additional environmental variables determined to further influence the stream nutrient yields included median annual percentage of point-source flow contributions to the streams, variables of land cover (percentage of forested land, agricultural land, and (or) forested land plus wetlands) in the watershed and (or) in the stream buffer, and drainage area. The regression tree models can serve as a tool for relating differences in select watershed attributes to differences in stream yields of nitrate, total N, and total P, which can provide beneficial information for improving nutrient management in streams throughout North Carolina and for reducing nutrient loads to coastal waters.

  15. Using Eco-hydrologic modeling in the Penobscot River Watershed to explore the role of climate and land use change on DOC concentration and flux

    Science.gov (United States)

    Rouhani, S. F. B. B.; Schaaf, C.; Douglas, E. M.; Huntington, T. G.; Kim, J.

    2017-12-01

    Dissolved Organic Carbon leaches from the terrestrial watersheds to serve as one of the largest sources of marine DOC. Runoff, slope, soil organic matter and land cover characteristics are the primary spatial factors controlling the variability of fluvial Dissolved Organic Carbon fluxes through the catchment. In large, more heterogeneous catchments, streamflow dissolved organic carbon dynamics are regulated by the combined effect of hydrological mechanisms and the proportion of major landscape elements, such as wetland and forested areas. A number of studies have demonstrated that the amount of wetlands, especially peatlands, controls the watershed level transport of DOC in streams.The Penobscot River Watershed is located in north-central Maine and drains into the Gulf of Maine. It is the second largest watershed in New England. The Penobscot River Watershed is primarily forested but also contains extensive bogs, marshes, and wooded swamps.Studying the spatial and temporal changes in DOC export in the Penobscot River Watershed allows us to better understand and detect carbon sinks to carbon source shifts (or vice versa) in northern forested ecosystems.The Regional Hydro-Ecological Simulation System, is a physical process based terrestrial model that has the ability to simulate both the source and transportation of DOC by combining both hydrological and ecological processes. The study is focused on simulating the DOC concentration and flux with RHESSys in the Penobscot River Watershed. The simulated results are compared with field measurements of DOC from the watershed and the model results from the LOADEST and the temporal DOC export patterns are explored. Future changes in the amount of streamflow DOC will also be investigated by using projected land cover and climate change scenarios. Incremental increases in the loss of wetland areas have been implemented to explore the sensitivity of this watershed to wetland loss and progressive changes in forested land cover

  16. Chapter 6: Incorporating rural community characteristics into forest management decisions

    Science.gov (United States)

    Mindy S. Crandall; Jane L. Harrison; Claire A. Montgomery

    2014-01-01

    As part of the Integrated Landscape Assessment Project, we developed a methodology for managers to include potential community benefits when considering forest management treatments. To do this, we created a watershed impact score that scores each watershed (potential source of wood material) with respect to the communities that are likely to benefit from increased...

  17. Watershed characterization and analysis using the VELMA ...

    Science.gov (United States)

    We developed a broadly applicable watershed simulator – VELMA (Visualizing Ecosystem and Land Management Assessments) – to characterize hydrological and ecological processes essential to the healthy functioning of watersheds, and to identify best management practices (BMPs) for restoring ecosystem services such as provisioning of clean water, food and fiber, and habitat for fish and wildlife. VELMA has been applied to agricultural, forest, rangeland and arctic watersheds across North America. Urban applications are under development. This seminar will discuss how VELMA is being used to help inform (1) salmon recovery planning in Puget Sound, and (2) water quality protection in Chesapeake Bay agricultural landscapes. These examples highlight the importance of model validation; how VELMA is being linked with additional models to aid BMP identification; and how the model is being transferred to community groups, tribes, and state and federal agencies engaged in environmental decision making. This invited seminar for the Washington State Department of Ecology will provide an overview of EPA’s VELMA watershed simulator and its applications for identifying best management practices for protecting and restoring vital ecosystem services, such as provisioning of clean water, food and fiber, and habitat for fish and wildlife. After the seminar, the presenter will meet with Department of Ecology staff to discuss the feasibility of including VELMA in their Puget Sound

  18. Resource communication: Variability in estimated runoff in a forested area based on different cartographic data sources

    Directory of Open Access Journals (Sweden)

    Laura Fragoso

    2017-10-01

    Full Text Available Aim of study: The goal of this study is to analyse variations in curve number (CN values produced by different cartographic data sources in a forested watershed, and determine which of them best fit with measured runoff volumes. Area of study: A forested watershed located in western Spain. Material and methods: Four digital cartographic data sources were used to determine the runoff CN in the watershed. Main results: None of the cartographic sources provided all the information necessary to determine properly the CN values. Our proposed methodology, focused on the tree canopy cover, improves the achieved results. Research highlights: The estimation of the CN value in forested areas should be attained as a function of tree canopy cover and new calibrated tables should be implemented in a local scale.

  19. Forecasts of forest conditions in regions of the United States under future scenarios: a technical document supporting the Forest Service 2012 RPA Assessment

    Science.gov (United States)

    David N. Wear; Robert Huggett; Ruhong Li; Benjamin Perryman; Shan Liu

    2013-01-01

    The 626 million acres of forests in the conterminous United States represent significant reserves of biodiversity and terrestrial carbon and provide substantial flows of highly valued ecosystem services, including timber products, watershed protection benefits, and recreation. This report describes forecasts of forest conditions for the conterminous United States in...

  20. Fifty years of forest hydrology in the Southeast

    Science.gov (United States)

    C. Rhett Jackson; Ge Sun; Devendra Amatya; Wayne T. Swank; Mark Riedel; Jim Patric; Tom Williams; Jim M. Vose; Carl Trettin; W. Michael Aust; R. Scott Beasley; Hamlin Williston; George G. Ice

    2004-01-01

    The forests of the southeastern United States are incredibly valuable and diverse, both for timber production and for the aquatic habitat they provide. These overlapping values and diverse conditions have spawned numerous studies to assess how forest management affects hydrology and water quality. In the mountains, key watershed studies include those conducted at USDA...

  1. Improved daily precipitation nitrate and ammonium concentration models for the Chesapeake Bay Watershed.

    Science.gov (United States)

    Grimm, J W; Lynch, J A

    2005-06-01

    Daily precipitation nitrate and ammonium concentration models were developed for the Chesapeake Bay Watershed (USA) using a linear least-squares regression approach and precipitation chemistry data from 29 National Atmospheric Deposition Program/National Trends Network (NADP/NTN) sites. Only weekly samples that comprised a single precipitation event were used in model development. The most significant variables in both ammonium and nitrate models included: precipitation volume, the number of days since the last event, a measure of seasonality, latitude, and the proportion of land within 8km covered by forest or devoted to industry and transportation. Additional variables included in the nitrate model were the proportion of land within 0.8km covered by water and/or forest. Local and regional ammonia and nitrogen oxide emissions were not as well correlated as land cover. Modeled concentrations compared very well with event chemistry data collected at six NADP/AirMoN sites within the Chesapeake Bay Watershed. Wet deposition estimates were also consistent with observed deposition at selected sites. Accurately describing the spatial distribution of precipitation volume throughout the watershed is important in providing critical estimates of wet-fall deposition of ammonium and nitrate.

  2. Adapting the Water Erosion Prediction Project (WEPP) model for forest applications

    Science.gov (United States)

    Shuhui Dun; Joan Q. Wu; William J. Elliot; Peter R. Robichaud; Dennis C. Flanagan; James R. Frankenberger; Robert E. Brown; Arthur C. Xu

    2009-01-01

    There has been an increasing public concern over forest stream pollution by excessive sedimentation due to natural or human disturbances. Adequate erosion simulation tools are needed for sound management of forest resources. The Water Erosion Prediction Project (WEPP) watershed model has proved useful in forest applications where Hortonian flow is the major form of...

  3. Land suitability assessment on a watershed of Loess Plateau using the analytic hierarchy process.

    Directory of Open Access Journals (Sweden)

    Xiaobo Yi

    Full Text Available In order to reduce soil erosion and desertification, the Sloping Land Conversion Program has been conducted in China for more than 15 years, and large areas of farmland have been converted to forest and grassland. However, this large-scale vegetation-restoration project has faced some key problems (e.g. soil drying that have limited the successful development of the current ecological-recovery policy. Therefore, it is necessary to know about the land use, vegetation, and soil, and their inter-relationships in order to identify the suitability of vegetation restoration. This study was conducted at the watershed level in the ecologically vulnerable region of the Loess Plateau, to evaluate the land suitability using the analytic hierarchy process (AHP. The results showed that (1 the area unsuitable for crops accounted for 73.3% of the watershed, and the main factors restricting cropland development were soil physical properties and soil nutrients; (2 the area suitable for grassland was about 86.7% of the watershed, with the remaining 13.3% being unsuitable; (3 an area of 3.95 km(2, accounting for 66.7% of the watershed, was unsuitable for forest. Overall, the grassland was found to be the most suitable land-use to support the aims of the Sloping Land Conversion Program in the Liudaogou watershed. Under the constraints of soil water shortage and nutrient deficits, crops and forests were considered to be inappropriate land uses in the study area, especially on sloping land. When selecting species for re-vegetation, non-native grass species with high water requirements should be avoided so as to guarantee the sustainable development of grassland and effective ecological functioning. Our study provides local land managers and farmers with valuable information about the inappropriateness of growing trees in the study area along with some information on species selection for planting in the semi-arid area of the Loess Plateau.

  4. Four decades of land-cover, land-use and hydroclimatology changes in the Itacaiúnas River watershed, southeastern Amazon.

    Science.gov (United States)

    Souza-Filho, Pedro Walfir M; de Souza, Everaldo B; Silva Júnior, Renato O; Nascimento, Wilson R; Versiani de Mendonça, Breno R; Guimarães, José Tasso F; Dall'Agnol, Roberto; Siqueira, José Oswaldo

    2016-02-01

    Long-term human-induced impacts have significantly changed the Amazonian landscape. The most dramatic land cover and land use (LCLU) changes began in the early 1970s with the establishment of the Trans-Amazon Highway and large government projects associated with the expansion of agricultural settlement and cattle ranching, which cleared significant tropical forest cover in the areas of new and accelerated human development. Taking the changes in the LCLU over the past four decades as a basis, this study aims to determine the consequences of land cover (forest and savanna) and land use (pasturelands, mining and urban) changes on the hydroclimatology of the Itacaiúnas River watershed area of the located in the southeastern Amazon region. We analyzed a multi-decadal Landsat dataset from 1973, 1984, 1994, 2004 and 2013 and a 40-yr time series of water discharge from the Itacaiúnas River, as well as air temperature and relative humidity data over this drainage area for the same period. We employed standard Landsat image processing techniques in conjunction with a geographic object-based image analysis and multi-resolution classification approach. With the goal of detecting possible long-term trends, non-parametric Mann-Kendall test was applied, based on a Sen slope estimator on a 40-yr annual PREC, TMED and RH time series, considering the spatial average of the entire watershed. In the 1970s, the region was entirely covered by forest (99%) and savanna (∼0.3%). Four decades later, only ∼48% of the tropical forest remains, while pasturelands occupy approximately 50% of the watershed area. Moreover, in protected areas, nearly 97% of the tropical forest remains conserved, while the forest cover of non-protected areas is quite fragmented and, consequently, unevenly distributed, covering an area of only 30%. Based on observational data analysis, there is evidence that the conversion of forest cover to extensive and homogeneous pasturelands was accompanied by systematic

  5. Forest management challenges for sustaining water resources in the Anthropocene

    Science.gov (United States)

    Ge Sun; James M. Vose

    2016-01-01

    The Earth has entered the Anthropocene epoch that is dominated by humans who demand unprecedented quantities of goods and services from forests. The science of forest hydrology and watershed management generated during the past century provides a basic understanding of relationships among forests and water and offers management principles that maximize the benefits of...

  6. Goddard DEVELOP Students: Using NASA Remote Sensing Technology to Study the Chesapeake Bay Watershed

    Science.gov (United States)

    Moore, Rachel

    2011-01-01

    The DEVELOP National Program is an Earth Science research internship, operating under NASA s Applied Sciences Program. Each spring, summer, and fall, DEVELOP interns form teams to investigate Earth Science related issues. Since the Fall of 2003, Goddard Space Flight Center (GSFC) has been home to one of 10 national DEVELOP teams. In past terms, students completed a variety of projects related to the Applied Sciences Applications of National Priority, such as Public Health, Natural Disasters, Water Resources, and Ecological Forecasting. These projects have focused on areas all over the world, including the United States, Africa, and Asia. Recently, Goddard DEVELOP students have turned their attention to a local environment, the Chesapeake Bay Watershed. The Chesapeake Bay Watershed is a complex and diverse ecosystem, spanning approximately 64,000 square miles. The watershed encompasses parts of six states: Delaware, Maryland, New York, Pennsylvania, Virginia, and West Virginia, as well as the District of Columbia. The Bay itself is the biggest estuary in the United States, with over 100,000 tributaries feeding into it. The ratio of fresh water to salt water varies throughout the Bay, allowing for a variety of habitats. The Bay s wetlands, marshes, forests, reefs, and rivers support more than 3,600 plant and animal species, including birds, mammals, reptiles, amphibians, fish, and crabs. The Bay is also commercially significant. It is ranked third in the nation in fishery catch, and supplies approximately 500 million pounds of seafood annually. In addition to its abundant flora and fauna, the Chesapeake Bay watershed is home to approximately 16.6 million people, who live and work throughout the watershed, and who use its diverse resources for recreational purposes. Over the past several decades, the population throughout the watershed has increased rapidly, resulting in land use changes, and ultimately decreasing the health of the Chesapeake Bay Watershed. Over the

  7. Potential water yield reduction due to forestation across China

    Science.gov (United States)

    Ge Sun; Guoyi Zhou; Zhiqiang Zhang; Xiaohua Wei; Steven G. McNulty; James M. Vose

    2006-01-01

    It is widely recognized that vegetation restoration will have positive effects on watershed health by reducing soil erosion and non-point source pollution, enhancing terrestrial and aquatic habitat, and increasing ecosystem carbon sequestration. However, the hydrologic consequences of forestation on degraded lands are not well studied in the forest hydrology community...

  8. Myanmar strategy for forest resource development

    Energy Technology Data Exchange (ETDEWEB)

    Wint, Sein Maung

    1993-10-01

    Myanmar strategy for forest resource development is presented under sub-headings of (1) Myanmar experience; (2) control against over-exploitation; (3) impact of population pressure; (4) forest plantation system on commercial plantation, industrial plantation, firewood plantation and watershed plantation; (5) people`s participation; (6) shifting cultivation. The forest resources of Myanmar have been changed for the past 136 years (1856-1992) successfully on sustained yield basis. Through proclamation of Forest Law (1992), active forestry and forest products research, upgrading of forestry educational institutions, modernization of forest inventory system and encouragement of downstream processing wood-based industries for value-added products, it was expected by the author that the forestry sector would be able to contribute more for the well-being of the people of Myanmar

  9. Myanmar strategy for forest resource development

    International Nuclear Information System (INIS)

    Sein Maung Wint

    1993-01-01

    Myanmar strategy for forest resource development is presented under sub-headings of (1) Myanmar experience; (2) control against over-exploitation; (3) impact of population pressure; (4) forest plantation system on commercial plantation, industrial plantation, firewood plantation and watershed plantation; (5) people's participation; (6) shifting cultivation. The forest resources of Myanmar have been changed for the past 136 years (1856-1992) successfully on sustained yield basis. Through proclamation of Forest Law (1992), active forestry and forest products research, upgrading of forestry educational institutions, modernization of forest inventory system and encouragement of downstream processing wood-based industries for value-added products, it was expected by the author that the forestry sector would be able to contribute more for the well-being of the people of Myanmar

  10. Minnesota Watersheds

    Data.gov (United States)

    Minnesota Department of Natural Resources — Statewide minor watershed delineations with major/minor watershed identifiers and names for provinces, major watersheds, and basins. Also included are watershed...

  11. Prioritizing Road Treatments using the Geomorphic Roads Analysis and Inventory Package (GRAIP) to Improve Watershed Conditions in the Wall Creek Watershed, Oregon

    Science.gov (United States)

    Day, K. T.; Black, T.; Clifton, C.; Luce, C.; McCune, S.; Nelson, N.

    2010-12-01

    Wall Creek, tributary to the North Fork John Day River in eastern Oregon, was identified as a priority watershed by the Umatilla National Forest for restoration in 2002. Most streams in this 518 km2 multi-ownership watershed are designated critical habitat for threatened steelhead. Eight streams are listed on the Oregon 303(d) list for elevated temperatures and excess sedimentation. Over 1000 km of public and private roads in the watershed present a major source of potential water quality and habitat impairment. We conducted a watershed-wide inventory of roads using the Geomorphic Roads Analysis and Inventory Package (GRAIP) in 2009 to quantify sediment contributions from roads to streams. GRAIP is a field and GIS-based model developed by the Forest Service Rocky Mountain Research Station and Utah State University that georeferences and quantifies road hydrologic connectivity, sediment production and delivery, mass wasting, and risk of diversion and plugging at stream crossings. Field survey and modeling produced data for 6,473 drainage locations on 726 km of road (most of the publically owned roads) quantifying the location and mass of sediment produced and delivered to streams. Findings indicate a relatively small subset of roads deliver the majority of road-produced fine sediment; 12 percent of the road length delivers 90 percent of the total fine sediment to streams. Overall fine sediment production in the watershed is relatively low (with an estimated background erosion rate of 518,000 kg/yr for the watershed) and sediment produced and delivered from the road system appears to be a modest addition. Road surfaces produce approximately 81,455 kg of fine sediment per year, with 20,976 kg/year delivered to the stream network. Fifty-nine gullies were observed, 41 of which received road runoff. Sixteen road-related landslides were also observed. The excavated volume of these features totals 3,922,000 kg which is equivalent to 175 years of fine sediment delivery at

  12. Floodplain Mapping for the Continental United States Using Machine Learning Techniques and Watershed Characteristics

    Science.gov (United States)

    Jafarzadegan, K.; Merwade, V.; Saksena, S.

    2017-12-01

    Using conventional hydrodynamic methods for floodplain mapping in large-scale and data-scarce regions is problematic due to the high cost of these methods, lack of reliable data and uncertainty propagation. In this study a new framework is proposed to generate 100-year floodplains for any gauged or ungauged watershed across the United States (U.S.). This framework uses Flood Insurance Rate Maps (FIRMs), topographic, climatic and land use data which are freely available for entire U.S. for floodplain mapping. The framework consists of three components, including a Random Forest classifier for watershed classification, a Probabilistic Threshold Binary Classifier (PTBC) for generating the floodplains, and a lookup table for linking the Random Forest classifier to the PTBC. The effectiveness and reliability of the proposed framework is tested on 145 watersheds from various geographical locations in the U.S. The validation results show that around 80 percent of total watersheds are predicted well, 14 percent have acceptable fit and less than five percent are predicted poorly compared to FIRMs. Another advantage of this framework is its ability in generating floodplains for all small rivers and tributaries. Due to the high accuracy and efficiency of this framework, it can be used as a preliminary decision making tool to generate 100-year floodplain maps for data-scarce regions and all tributaries where hydrodynamic methods are difficult to use.

  13. Modeling soil erosion and transport on forest landscape

    Science.gov (United States)

    Ge Sun; Steven G McNulty

    1998-01-01

    Century-long studies on the impacts of forest management in North America suggest sediment can cause major reduction on stream water quality. Soil erosion patterns in forest watersheds are patchy and heterogeneous. Therefore, patterns of soil erosion are difficult to model and predict. The objective of this study is to develop a user friendly management tool for land...

  14. Reptile Communities Under Diverse Forest Management in the Ouachita Mountains, Arkansas

    Science.gov (United States)

    Paul A. Shipman; Stanley F. Fox; Ronald E. Thill; Joseph P. Phelps; David M. Leslie

    2004-01-01

    Abstract - From May 1995 to March 1999, we censused reptiles in the Ouachita Mountains, Arkansas, on approximately 60 plots on each of four forested watersheds five times per year, with new plots each year. We found that the least intensively managed watershed had significantly lower per-plot reptile abundances, species richness, and diversity....

  15. Tropical land-sea couplings: Role of watershed deforestation, mangrove estuary processing, and marine inputs on N fluxes in coastal Pacific Panama.

    Science.gov (United States)

    Valiela, Ivan; Elmstrom, Elizabeth; Lloret, Javier; Stone, Thomas; Camilli, Luis

    2018-07-15

    We review data from coastal Pacific Panama and other tropical coasts with two aims. First, we defined inputs and losses of nitrogen (N) mediating connectivity of watersheds, mangrove estuaries, and coastal sea. N entering watersheds-mainly via N fixation (79-86%)-was largely intercepted; N discharges to mangrove estuaries (3-6%), small compared to N inputs to watersheds, nonetheless significantly supplied N to mangrove estuaries. Inputs to mangrove estuaries (including watershed discharges, and marine inputs during flood tides) were matched by losses (mainly denitrification and export during ebb tides). Mangrove estuary subsidies of coastal marine food webs take place by export of forms of N [DON (62.5%), PN (9.1%), and litter N (12.9%)] that provide dissimilative and assimilative subsidies. N fixation, denitrification, and tidal exchanges were major processes, and DON was major form of N involved in connecting fluxes in and out of mangrove estuaries. Second, we assessed effects of watershed forest cover on connectivity. Decreased watershed forest cover lowered N inputs, interception, and discharge into receiving mangrove estuaries. These imprints of forest cover were erased during transit of N through estuaries, owing to internal N cycle transformations, and differences in relative area of watersheds and estuaries. Largest losses of N consisted of water transport of energy-rich compounds, particularly DON. N losses were similar in magnitude to N inputs from sea, calculated without considering contribution by intermittent coastal upwelling, and hence likely under-estimated. Pacific Panama mangrove estuaries are exposed to major inputs of N from land and sea, which emphasizes the high degree of bi-directional connectivity in these coupled ecosystems. Pacific Panama is still lightly affected by human or global changes. Increased deforestation can be expected, as well as changes in ENSO, which will surely raise watershed-derived loads of N, as well as significantly

  16. The land use patterns for soil organic carbon conservation at Endanga watershed Southeast Sulawesi Indonesia

    Science.gov (United States)

    Leomo, S.; Ginting, S.; Sabaruddin, L.; Tufaila, M.; Muhidin

    2018-02-01

    The Endanga basin is one part of the Konaweeha watershed located in South Konawe, Southeast Sulawesi Province, covering an area of 1,353.67 hectares. The land use patterns in Endanga Watershed contained forests, shrubs, oil palm plantations, pepper fields, and cultivated fields of field rice, corn monoculture and intercropping of peanuts and corn. This watershed needs serious attention because most of its territory is on slope of 15-40%, with erosion hazard levels (EHL) varying from mild erosion to severe erosion. The loss of organic carbon (C-organic) soil is measured from the soil carried along with the surface stream and into the reservoir on various land uses. The result measurement of C-organic soil loss on forest land use is 14.02 kg ha-1, shrubs land 22.71 kg ha-1, oil palm 151.32 kg ha-1, pepper garden 93.69 kg ha-1, field rice 313.80 kg.ha-1, monoculture of maize 142.44 kg ha-1, intercropped maize and corn 51.10 kg ha-1 and open land 1,909.16 kg ha-1. The forest land and shrubs is best in conserving soil C-organic, but economically unfavorable for the community, so land use pattern for intercropping and pepper plantation can be used for soil C-organic conservation

  17. Mechanisms and rates of atmospheric deposition of selected trace elements and sulfate to a deciduous forest watershed. [Roles of dry and wet deposition concentrations measured in Walker Branch Watershed

    Energy Technology Data Exchange (ETDEWEB)

    Lindberg, S.E.; Harriss, R.C.; Turner, R.R.; Shriner, D.S.; Huff, D.D.

    1979-06-01

    The critical links between anthropogenic emissions to the atmosphere and their effects on ecosystems are the mechanisms and rates of atmospheric deposition. The atmospheric input of several trace elements and sulfate to a deciduous forest canopy is quantified and the major mechanisms of deposition are determined. The study area was Walker Branch Watershed (WBW) in eastern Tennessee. The presence of a significant quantity of fly ash and dispersed soil particles on upward-facing leaf and flat surfaces suggested sedimentation to be a major mechanism of dry deposition to upper canopy elements. The agreement for deposition rates measured to inert, flat surfaces and to leaves was good for Cd, SO/sub 4//sup =/, Zn, and Mn but poor for Pb. The precipitation concentrations of H/sup +/, Pb, Mn, and SO/sub 4//sup =/ reached maximum values during the summer months. About 90% of the wet deposition of Pb and SO/sub 4//sup =/ was attributed to scavenging by in-cloud processes while for Cd and Mn, removal by in-cloud scavenging accounted for 60 to 70% of the deposition. The interception of incoming rain by the forest canopy resulted in a net increase in the concentrations of Cd, Mn, Pb, Zn, and SO/sub 4//sup =/ but a net decrease in the concentration of H/sup +/. The source of these elements in the forest canopy was primarily dry deposited aerosols for Pb, primarily internal plant leaching for Mn, Cd, and Zn, and an approximately equal combination of the two for SO/sub 4//sup =/. Significant fractions of the total annual elemental flux to the forest floor in a representative chestnut oak stand were attributable to external sources for Pb (99%), Zn (44%), Cd (42%), SO/sub 4//sup =/ (39%), and Mn (14%), the remainder being related to internal element cycling mechanisms. On an annual scale the dry deposition process constituted a significant fraction of the total atmospheric input. (ERB)

  18. Watershed Landscape Ecology: Interdisciplinary and Field-based Learning in the Northeast Creek Watershed, Mount Desert Island, Maine

    Science.gov (United States)

    Hall, S. R.; Anderson, J.; Rajakaruna, N.; Cass, D.

    2014-12-01

    At the College of the Atlantic, Bar Harbor, Maine, undergraduate students have the opportunity to design their own curriculum within a major of "Human Ecology." To enable students to have early research experiences, we developed a field-based interdisciplinary program for students to learn and practice field methods in a variety of disciplines, Earth Science, Botany, Chemistry, and Wildlife Biology at three specific field sites within a single watershed on Mt. Desert Island. As the Northeast Creek watershed was the site of previous water quality studies, this program of courses enabled continued monitoring of portions of the watershed. The program includes 4 new courses: Critical Zone 1, Critical Zone 2, Wildlife Biology, and Botany. In Critical Zone 1 students are introduced to general topics in Earth Science and learn to use ArcGIS to make basic maps. In Critical Zone 2, Wildlife Biology, and Botany, students are in the field every week using classic field tools and methods. All three of these courses use the same three general field areas: two with working farms at the middle and lower portion of the watershed and one uninhabited forested property in the higher relief headwaters of the watershed. Students collect daily surface water chemistry data at five stream sites within the watershed, complete basic geologic bedrock and geomorphic mapping, conduct wildlife surveys, botanical surveys, and monitor weather patterns at each of the main sites. Beyond the class data collected and synthesized, students also complete group independent study projects at focused field sites, some of which have turned into much larger research projects. This program is an opportunity for students and faculty with varied interests and expertise to work together to study a specific field locality over multiple years. We see this model as enhancing a number of positive education components: field-based learning, teamwork, problem solving, interdisciplinary discussion, multiple faculty

  19. Watershed Response to Climate Change and Fire-Burns in the Upper Umatilla River Basin, USA

    Directory of Open Access Journals (Sweden)

    Kimberly Yazzie

    2017-02-01

    Full Text Available This study analyzed watershed response to climate change and forest fire impacts in the upper Umatilla River Basin (URB, Oregon, using the precipitation runoff modeling system. Ten global climate models using Coupled Intercomparison Project Phase 5 experiments with Representative Concentration Pathways (RCP 4.5 and 8.5 were used to simulate the effects of climate and fire-burns on runoff behavior throughout the 21st century. We observed the center timing (CT of flow, seasonal flows, snow water equivalent (SWE and basin recharge. In the upper URB, hydrologic regime shifts from a snow-rain-dominated to rain-dominated basin. Ensemble mean CT occurs 27 days earlier in RCP 4.5 and 33 days earlier in RCP 8.5, in comparison to historic conditions (1980s by the end of the 21st century. After forest cover reduction in the 2080s, CT occurs 35 days earlier in RCP 4.5 and 29 days earlier in RCP 8.5. The difference in mean CT after fire-burns may be due to projected changes in the individual climate model. Winter flow is projected to decline after forest cover reduction in the 2080s by 85% and 72% in RCP 4.5 and RCP 8.5, in comparison to 98% change in ensemble mean winter flows in the 2080s before forest cover reduction. The ratio of ensemble mean snow water equivalent to precipitation substantially decreases by 81% and 91% in the 2050s and 2080s before forest cover reduction and a decrease of 90% in RCP 4.5 and 99% in RCP 8.5 in the 2080s after fire-burns. Mean basin recharge is 10% and 14% lower in the 2080s before fire-burns and after fire-burns, and it decreases by 13% in RCP 4.5 and decreases 22% in RCP 8.5 in the 2080s in comparison to historical conditions. Mixed results for recharge after forest cover reduction suggest that an increase may be due to the size of burned areas, decreased canopy interception and less evaporation occurring at the watershed surface, increasing the potential for infiltration. The effects of fire on the watershed system are

  20. Carbon dynamics in lakes of the boreal forest under a changing climate

    Energy Technology Data Exchange (ETDEWEB)

    Benoy, G.; Wrona, F. [Environment Canada, Saskatoon, SK (Canada). National Water Research Inst.; Cash, K. [Environment Canada, Saskatoon, SK (Canada). Prairie and Northern Wildlife Research Centre; McCauley, E. [Calgary Univ., AB (Canada). Dept. of Biology

    2007-09-15

    This article reviewed factors influencing lake ecosystem carbon dynamics in boreal forest regions and identified research areas needed to accurately forecast the impacts of climate change on carbon pools and flux rates. The review suggested that carbon pools in profundal and littoral sediments across the boreal forest should be identified. Climate change experiments should be conducted to quantify ecosystem carbon dynamics as well as changes in aquatic food web structures. Whole system experiments are also needed to examine the hydrologic and bio-geochemical conditions in which allochthonous carbon is integrated into food webs in potentially drier climates. Results also indicated the need for a watershed-scale assessment of carbon budgets for lakes in transitional zones between boreal forests, prairies, parklands, forests, and tundra. It was concluded that studies are also needed to investigate the integration of lacustrine carbon pools and flux rates on carbon budgets at both the local watershed and boreal forest biome scale. 113 refs., 3 figs.

  1. Influences of watershed geomorphology on extent and composition of riparian vegetation

    Science.gov (United States)

    Blake M. Engelhardt; Peter J. Weisberg; Jeanne C. Chambers

    2011-01-01

    Watershed (drainage basin) morphometry and geology were derived from digital data sets (DEMs and geologic maps). Riparian corridors were classified into five vegetation types (riparian forest, riparian shrub, wet/mesic meadow, dry meadow and shrub dry meadow) using high-resolution aerial photography. Regression and multivariate analyses were used to relate geomorphic...

  2. When Everything Changes: Mountaintop Mining Effects on Watershed Hydrology

    Science.gov (United States)

    Nippgen, F.; Ross, M. R.; McGlynn, B. L.; Bernhardt, E. S.

    2015-12-01

    Mountaintop removal coal mining (MTM) in the Central Appalachians has expanded over the last 40 years to cover ~7% of this mountainous landscape. MTM operations remove mountaintops and ridges with explosives and machinery to access underlying coal seams. Much of this crushed rock overburden is subsequently deposited into nearby valleys, creating valley fills that often bury headwater streams. In contrast to other disturbances such as forest clear-cutting, perturbations from MTM can extend hundreds of meters deep into the critical zone and completely reshape landscapes. Despite the expansiveness and intensity of the disturbance, MTM has only recently begun to receive focused attention from the hydrologic community and the effect of MTM on the hydrology of impacted watersheds is still not well understood. We are using a two-pronged approach consisting of GIS analysis to quantify spoil volumes and landscape change, together with empirical analysis and modeling of rainfall and runoff data collected in two sets of paired watersheds. We seek to investigate how MTM affects basic hydrologic metrics, including storm peakflows, runoff response times, baseflow, statistics of flow duration curves, and longer-term water balances. Each pair consists of a mined and an unmined watershed; the first set contains headwater streams (size ~100ha), the second set consists of 3rd order streams, draining ~3500ha. Mining covers ~ 95% of the headwater watershed, and 40% of the 3rd-order watershed. Initial GIS analysis indicates that the overburden moved during the mining process could be up to three times greater than previously estimated. Storm runoff peaks in the mined watersheds were muted as compared to the unmined watersheds and runoff ratios were reduced by up to 75% during both wet and dry antecedent conditions. The natural reference watersheds were highly responsive while the additional storage in the mined watersheds led to decreased peak flows during storms and enhanced baseflow

  3. Groundwater flow modelling in the upper Anga'a river watershed ...

    African Journals Online (AJOL)

    ISHIOMA

    The Anga'a River watershed is located within the Yaounde IV district, South-east of Yaounde City,. Cameroon. ... B: A nga'a drainage basin in the City of Yaoundé ... show the potential danger of groundwater pollution by ... The city of Yaounde is located about 250 km from the Atlantic coast .... forest zone of south Cameroon.

  4. Ecosystem consequences of tree monodominance for nitrogen cycling in lowland tropical forest.

    Science.gov (United States)

    Brookshire, E N Jack; Thomas, Steven A

    2013-01-01

    Understanding how plant functional traits shape nutrient limitation and cycling on land is a major challenge in ecology. This is especially true for lowland forest ecosystems of the tropics which can be taxonomically and functionally diverse and rich in bioavailable nitrogen (N). In many tropical regions, however, diverse forests occur side-by-side with monodominant forest (one species >60% of canopy); the long-term biogeochemical consequences of tree monodominance are unclear. Particularly uncertain is whether the monodominant plant-soil system modifies nutrient balance at the ecosystem level. Here, we use chemical and stable isotope techniques to examine N cycling in old-growth Mora excelsa and diverse watershed rainforests on the island of Trinidad. Across 26 small watershed forests and 4 years, we show that Mora monodominance reduces bioavailable nitrate in the plant-soil system to exceedingly low levels which, in turn, results in small hydrologic and gaseous N losses at the watershed-level relative to adjacent N-rich diverse forests. Bioavailable N in soils and streams remained low and remarkably stable through time in Mora forests; N levels in diverse forests, on the other hand, showed high sensitivity to seasonal and inter-annual rainfall variation. Total mineral N losses from diverse forests exceeded inputs from atmospheric deposition, consistent with N saturation, while losses from Mora forests did not, suggesting N limitation. Our measures suggest that this difference cannot be explained by environmental factors but instead by low internal production and efficient retention of bioavailable N in the Mora plant-soil system. These results demonstrate ecosystem-level consequences of a tree species on the N cycle opposite to cases where trees enhance ecosystem N supply via N2 fixation and suggest that, over time, Mora monodominance may generate progressive N draw-down in the plant-soil system.

  5. Ecosystem consequences of tree monodominance for nitrogen cycling in lowland tropical forest.

    Directory of Open Access Journals (Sweden)

    E N Jack Brookshire

    Full Text Available Understanding how plant functional traits shape nutrient limitation and cycling on land is a major challenge in ecology. This is especially true for lowland forest ecosystems of the tropics which can be taxonomically and functionally diverse and rich in bioavailable nitrogen (N. In many tropical regions, however, diverse forests occur side-by-side with monodominant forest (one species >60% of canopy; the long-term biogeochemical consequences of tree monodominance are unclear. Particularly uncertain is whether the monodominant plant-soil system modifies nutrient balance at the ecosystem level. Here, we use chemical and stable isotope techniques to examine N cycling in old-growth Mora excelsa and diverse watershed rainforests on the island of Trinidad. Across 26 small watershed forests and 4 years, we show that Mora monodominance reduces bioavailable nitrate in the plant-soil system to exceedingly low levels which, in turn, results in small hydrologic and gaseous N losses at the watershed-level relative to adjacent N-rich diverse forests. Bioavailable N in soils and streams remained low and remarkably stable through time in Mora forests; N levels in diverse forests, on the other hand, showed high sensitivity to seasonal and inter-annual rainfall variation. Total mineral N losses from diverse forests exceeded inputs from atmospheric deposition, consistent with N saturation, while losses from Mora forests did not, suggesting N limitation. Our measures suggest that this difference cannot be explained by environmental factors but instead by low internal production and efficient retention of bioavailable N in the Mora plant-soil system. These results demonstrate ecosystem-level consequences of a tree species on the N cycle opposite to cases where trees enhance ecosystem N supply via N2 fixation and suggest that, over time, Mora monodominance may generate progressive N draw-down in the plant-soil system.

  6. Critical zone structure controls concentration-discharge relationships and solute generation in forested tropical montane watersheds

    Science.gov (United States)

    Wymore, Adam S.; Brereton, Richard L.; Ibarra, Daniel E.; Maher, Kate; McDowell, William H.

    2017-07-01

    Concentration-discharge (C-Q) relationships are poorly known for tropical watersheds, even though the tropics contribute a disproportionate amount of solutes to the global ocean. The Luquillo Mountains in Puerto Rico offer an ideal environment to examine C-Q relationships across a heterogeneous tropical landscape. We use 10-30 years of weekly stream chemistry data across 10 watersheds to examine C-Q relationships for weathering products (SiO2(aq), Ca2+, Mg2+, and Na+) and biologically controlled solutes (dissolved organic carbon [DOC], dissolved organic nitrogen [DON], NH4+, NO3-, PO43-, K+, and SO42-). We analyze C-Q relationships using power law equations and a solute production model and use principal component analysis to test hypotheses regarding how the structure of the critical zone controls solute generation. Volcaniclastic watersheds had higher concentrations of weathering solutes and smaller tributaries were approximately threefold more efficient at generating these solutes than larger rivers. Lithology and vegetation explained a significant amount of variation in the theoretical maximum concentrations of weathering solutes (r2 = 0.43-0.48) and in the C-Q relationships of PO43- (r2 = 0.63) and SiO2(aq) (r2 = 0.47). However, the direction and magnitude of these relationships varied. Across watersheds, various forms of N and P displayed variable C-Q relationships, while DOC was consistently enriched with increasing discharge. Results suggest that PO43- may be a useful indicator of watershed function. Relationships between C-Q and landscape characteristics indicate the extent to which the structure and function of the Critical zone controls watershed solute fluxes.

  7. Watershed Urbanization Linked to Differences in Stream Bacterial Community Composition

    Directory of Open Access Journals (Sweden)

    Jacob D. Hosen

    2017-08-01

    Full Text Available Urbanization strongly influences headwater stream chemistry and hydrology, but little is known about how these conditions impact bacterial community composition. We predicted that urbanization would impact bacterial community composition, but that stream water column bacterial communities would be most strongly linked to urbanization at a watershed-scale, as measured by impervious cover, while sediment bacterial communities would correlate with environmental conditions at the scale of stream reaches. To test this hypothesis, we determined bacterial community composition in the water column and sediment of headwater streams located across a gradient of watershed impervious cover using high-throughput 16S rRNA gene amplicon sequencing. Alpha diversity metrics did not show a strong response to catchment urbanization, but beta diversity was significantly related to watershed impervious cover with significant differences also found between water column and sediment samples. Samples grouped primarily according to habitat—water column vs. sediment—with a significant response to watershed impervious cover nested within each habitat type. Compositional shifts for communities in urbanized streams indicated an increase in taxa associated with human activity including bacteria from the genus Polynucleobacter, which is widespread, but has been associated with eutrophic conditions in larger water bodies. Another indicator of communities in urbanized streams was an OTU from the genus Gallionella, which is linked to corrosion of water distribution systems. To identify changes in bacterial community interactions, bacterial co-occurrence networks were generated from urban and forested samples. The urbanized co-occurrence network was much smaller and had fewer co-occurrence events per taxon than forested equivalents, indicating a loss of keystone taxa with urbanization. Our results suggest that urbanization has significant impacts on the community composition

  8. Metal cycling within mountain pine beetle impacted watersheds of Keystone Gulch, Colorado

    Science.gov (United States)

    Heil, E. M.; Navarre-Sitchler, A.; Wanty, R. B.

    2016-12-01

    Metal cycling in mountain watersheds may be altered due to rapid landscape changes. Previous studies have examined the impact of deforestation and wildfires, on the fate and transport of metals in watersheds. However, we have only begun to understand changes in metal cycling in watersheds impacted by the mountain pine beetle. Warming climates and extended droughts have enabled pine beetles to impact larger areas. In these areas tree death occurs an average of three years after the initial infestation. In this short period of time the trees stop transpiring, defoliate, and die. The rapid deposition of pine needles to the forest floor, and subsequent decomposition of the needles, increases organic carbon (OC) availability and release metals that are stored in the impacted watersheds. Consequently, both OC and metal fluxes into and through the beetle-infested watersheds may be larger than those in non-infested watersheds. Four watersheds along Keystone Gulch Rd., located in Keystone, CO, were chosen for soil, water, and needle sampling because of their similar bedrock, drainage area, tree density and type, aspect, and their varying degree of pine beetle infestation. Sequential extractions using simulated rainwater, MgCl2, and pyrophosphate (representing soil pore water, exchangeable fraction, and organically bound metals) were performed on the Keystone Gulch soil samples to develop a better understanding of the distribution of metals in soils. Samples were classified by degree of beetle impact within and between the watersheds. The most obvious differences in the soil extractions between the four watersheds were observed for aluminum and iron and to a slightly lesser extent copper and zinc. In general, aluminum, iron, and zinc concentrations were higher while copper concentrations were lower in soils from less beetle-impacted watersheds. Metal concentrations in stream waters will be evaluated in the context of metal mobility through and out of the watershed.

  9. The impact of forest thinning on the reliability of water supply in central Arizona.

    Directory of Open Access Journals (Sweden)

    Silvio Simonit

    Full Text Available Economic growth in Central Arizona, as in other semiarid systems characterized by low and variable rainfall, has historically depended on the effectiveness of strategies to manage water supply risks. Traditionally, the management of supply risks includes three elements: hard infrastructures, landscape management within the watershed, and a supporting set of institutions of which water markets are frequently the most important. In this paper we model the interactions between these elements. A forest restoration initiative in Central Arizona (the Four Forest Restoration Initiative, or 4FRI will result in thinning of ponderosa pine forests in the upper watershed, with potential implications for both sedimentation rates and water delivery to reservoirs. Specifically, we model the net effect of ponderosa pine forest thinning across the Salt and Verde River watersheds on the reliability and cost of water supply to the Phoenix metropolitan area. We conclude that the sediment impacts of forest thinning (up to 50% of canopy cover are unlikely to compromise the reliability of the reservoir system while thinning has the potential to increase annual water supply by 8%. This represents an estimated net present value of surface water storage of $104 million, considering both water consumption and hydropower generation.

  10. The Impact of Forest Thinning on the Reliability of Water Supply in Central Arizona

    Science.gov (United States)

    Simonit, Silvio; Connors, John P.; Yoo, James; Kinzig, Ann; Perrings, Charles

    2015-01-01

    Economic growth in Central Arizona, as in other semiarid systems characterized by low and variable rainfall, has historically depended on the effectiveness of strategies to manage water supply risks. Traditionally, the management of supply risks includes three elements: hard infrastructures, landscape management within the watershed, and a supporting set of institutions of which water markets are frequently the most important. In this paper we model the interactions between these elements. A forest restoration initiative in Central Arizona (the Four Forest Restoration Initiative, or 4FRI) will result in thinning of ponderosa pine forests in the upper watershed, with potential implications for both sedimentation rates and water delivery to reservoirs. Specifically, we model the net effect of ponderosa pine forest thinning across the Salt and Verde River watersheds on the reliability and cost of water supply to the Phoenix metropolitan area. We conclude that the sediment impacts of forest thinning (up to 50% of canopy cover) are unlikely to compromise the reliability of the reservoir system while thinning has the potential to increase annual water supply by 8%. This represents an estimated net present value of surface water storage of $104 million, considering both water consumption and hydropower generation. PMID:25835003

  11. Simulation, calibration and validation protocols for the model 3D-CMCC-CNR-FEM: a case study in the Bonis’ watershed (Calabria, Italy

    Directory of Open Access Journals (Sweden)

    Collalti A

    2017-08-01

    Full Text Available Simulation, calibration and validation protocols for the model 3D-CMCC-CNR-FEM: a case study in the Bonis’ watershed (Calabria, Italy. At present, the climate changes issue is perhaps the greatest threat that is affecting people and the environment. Forest ecosystems have a key role in the mitigation of climate change. In this context, the prediction of the evolution and growth dynamics of the forests including carbon and water fluxes, and in relation to forest management has become a primary objective. The present study aims at defining a protocol for data collection and the workflow for using the 3D-CMCC-CNR-FEM model in a small mountain watershed in the Calabria region. Within this work we synergistically integrate data coming from different methods (e.g., LiDAR, eddy covariance and sample area to predict forest dynamics (growth, carbon and water fluxes. Carbon and water fluxes will be simulated considering also the effects of forest management.

  12. Effect of land use land cover change on soil erosion potential in an agricultural watershed.

    Science.gov (United States)

    Sharma, Arabinda; Tiwari, Kamlesh N; Bhadoria, P B S

    2011-02-01

    Universal soil loss equation (USLE) was used in conjunction with a geographic information system to determine the influence of land use and land cover change (LUCC) on soil erosion potential of a reservoir catchment during the period 1989 to 2004. Results showed that the mean soil erosion potential of the watershed was increased slightly from 12.11 t ha(-1) year(-1) in the year 1989 to 13.21 t ha(-1) year(-1) in the year 2004. Spatial analysis revealed that the disappearance of forest patches from relatively flat areas, increased in wasteland in steep slope, and intensification of cultivation practice in relatively more erosion-prone soil were the main factors contributing toward the increased soil erosion potential of the watershed during the study period. Results indicated that transition of other land use land cover (LUC) categories to cropland was the most detrimental to watershed in terms of soil loss while forest acted as the most effective barrier to soil loss. A p value of 0.5503 obtained for two-tailed paired t test between the mean erosion potential of microwatersheds in 1989 and 2004 also indicated towards a moderate change in soil erosion potential of the watershed over the studied period. This study revealed that the spatial location of LUC parcels with respect to terrain and associated soil properties should be an important consideration in soil erosion assessment process.

  13. Non-timber forest products: ramps in the Waynesville, NC watershed

    Science.gov (United States)

    Kristina Connor; Jim Chamberlain III; Hilliard Gibbs Jr.; Matt Winn

    2015-01-01

    The potential of forest farming was noted as far back as 1929, but the recognition of its importance dates back only 20 to 30 years. The U.S. market for harvested foods and medicinal plants from forests now exceeds $4 billion annually. Ramps (Allium tricoccum Aiton), or wild leeks, grow in patches in the rich moist forests of the eastern United...

  14. Can forest watershed management mitigate climate change impacts on water resources?

    Science.gov (United States)

    James M. Vose; Chelcy R. Ford; Stephanie Laseter; Salli Dymond; GE Sun; Mary Beth Adams; Stephen Sebestyen; John Campbell; Charles Luce; Devendra Amatya; Kelly Elder; Tamara. Heartsill-Scalley

    2012-01-01

    Long-term hydrology and climate data from United States Forest Service Experimental Forests and Ranges (EFR) provide critical information on the interactions among climate, streamflow, and forest management practices. We examined the relationships among streamflow responses to climate variation and forest management using long-term data. Analysis of climate data from a...

  15. Conservation Management of Agriculture Land using Geospatial Approach (A Case Study in the Bone Watershed, Gorontalo Province, Indonesia

    Directory of Open Access Journals (Sweden)

    Maryati Sri

    2018-01-01

    Full Text Available Bone Watershed is one of the major watersheds in Gorontalo Province. Bone watershed has a very important role for the people of Gorontalo Province. The role of Bone Watershed is mainly related to the providing clean water, producing oxygen, controlling flood, providing habitat for endemic flora fauna and other environmental functions. The role of Bone Watershed for the community’s economic sector is also very important, the Bone watershed provides livelihood for surrounding communities includes fertile land resources for agriculture and plantations, forest products, and livestock feed. This research is important considering the Bone watershed has limited availability of land for agriculture and the high risk of natural disasters such as floods and landslides. Geospatial data includes topography map, landform map, soil map, integrated with field survey results and soil properties were analized to determine conservation management of agriculture land in the Bone Watershed, Gorontalo Province, Indonesia. The result of this study shows that based on soil properties and physical land characteristics, land use for agriculture should consider appropriate conservation techniques, land capability and respect to local wisdom.

  16. Conservation Management of Agriculture Land using Geospatial Approach (A Case Study in the Bone Watershed, Gorontalo Province, Indonesia)

    Science.gov (United States)

    Maryati, Sri; Eraku, Sunarty; Kasim, Muh

    2018-02-01

    Bone Watershed is one of the major watersheds in Gorontalo Province. Bone watershed has a very important role for the people of Gorontalo Province. The role of Bone Watershed is mainly related to the providing clean water, producing oxygen, controlling flood, providing habitat for endemic flora fauna and other environmental functions. The role of Bone Watershed for the community's economic sector is also very important, the Bone watershed provides livelihood for surrounding communities includes fertile land resources for agriculture and plantations, forest products, and livestock feed. This research is important considering the Bone watershed has limited availability of land for agriculture and the high risk of natural disasters such as floods and landslides. Geospatial data includes topography map, landform map, soil map, integrated with field survey results and soil properties were analized to determine conservation management of agriculture land in the Bone Watershed, Gorontalo Province, Indonesia. The result of this study shows that based on soil properties and physical land characteristics, land use for agriculture should consider appropriate conservation techniques, land capability and respect to local wisdom.

  17. Calibration and validation of the SWAT model for a forested watershed in coastal South Carolina

    Science.gov (United States)

    Devendra M. Amatya; Elizabeth B. Haley; Norman S. Levine; Timothy J. Callahan; Artur Radecki-Pawlik; Manoj K. Jha

    2008-01-01

    Modeling the hydrology of low-gradient coastal watersheds on shallow, poorly drained soils is a challenging task due to the complexities in watershed delineation, runoff generation processes and pathways, flooding, and submergence caused by tropical storms. The objective of the study is to calibrate and validate a GIS-based spatially-distributed hydrologic model, SWAT...

  18. Evaluating long-term cumulative hydrologic effects of forest management: a conceptual approach

    Science.gov (United States)

    Robert R. Ziemer

    1992-01-01

    It is impractical to address experimentally many aspects of cumulative hydrologic effects, since to do so would require studying large watersheds for a century or more. Monte Carlo simulations were conducted using three hypothetical 10,000-ha fifth-order forested watersheds. Most of the physical processes expressed by the model are transferable from temperate to...

  19. Disturbance history and stand dynamics in secondary and old-growth forests of the Southern Appalachian Mountains, USA

    Science.gov (United States)

    Sarah M. Butler; Alan S. White; Katherine J. Elliott; Robert S Seymour

    2014-01-01

    BUTLER, S. M. (Family Forest Research Center, University of Massachusetts, Amherst, MA 01003), A. S. WHITE (School of Forest Resources, University of Maine, Orono, ME 04469-5755), K. J. ELLIOTT (Coweeta Hydrologic Laboratory, Center for Forest Watershed Science, Southern Research Station, USDA Forest Service, Otto, NC 28763) AND R. S. SEYMOUR (School of Forest...

  20. Wind River Watershed Restoration: 1999 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Connolly, Patrick J.

    2001-09-01

    This document represents work conducted as part of the Wind River Watershed Restoration Project during its first year of funding through the Bonneville Power Administration (BPA). The project is a comprehensive effort involving public and private entities seeking to restore water quality and fishery resources in the basin through cooperative actions. Project elements include coordination, watershed assessment, restoration, monitoring, and education. Entities involved with implementing project components are the Underwood Conservation District (UCD), USDA Forest Service (USFS), U.S. Geological Survey--Columbia River Research Lab (USGS-CRRL), and WA Department of Fish & Wildlife (WDFW). Following categories given in the FY1999 Statement of Work, the broad categories, the related objectives, and the entities associated with each objective (lead entity in boldface) were as follows: Coordination--Objective 1: Coordinate the Wind River watershed Action Committee (AC) and Technical Advisory Committee (TAC) to develop a prioritized list of watershed enhancement projects. Monitoring--Objective 2: Monitor natural production of juvenile, smolt, and adult steelhead in the Wind River subbasin. Objective 3: Evaluate physical habitat conditions in the Wind River subbasin. Assessment--Objective 4: Assess watershed health using an ecosystem-based diagnostic model that will provide the technical basis to prioritize out-year restoration projects. Restoration--Objective 5: Reduce road related sediment sources by reducing road densities to less than 2 miles per square mile. Objective 6: Rehabilitate riparian corridors, flood plains, and channel morphology to reduce maximum water temperatures to less than 61 F, to increase bank stability to greater than 90%, to reduce bankfull width to depth ratios to less than 30, and to provide natural levels of pools and cover for fish. Objective 7: Maintain and evaluate passage for adult and juvenile steelhead at artificial barriers. Education

  1. Effects of mountain agriculture on nutrient cycling at upstream watersheds

    Science.gov (United States)

    Lin, T.-C.; Shaner, P. L.; Wang, L.-J.; Shih, Y.-T.; Wang, C.-P.; Huang, G.-H.; Huang, J.-C.

    2015-05-01

    The expansion of agriculture to rugged mountains can exacerbate negative impacts of agriculture activities on ecosystem function. In this study, we monitored streamwater chemistry of four watersheds with varying proportions of agricultural lands (0.4, 3, 17, 22%) and rainfall chemistry of two of the four watersheds at Feitsui Reservoir Watershed in northern Taiwan to examine the effects of agriculture on watershed nutrient cycling. We found that the greater the proportions of agricultural lands, the higher the ion concentrations, which is evident for fertilizer-associated ions (NO3-, K+) but not for ions that are rich in soils (SO42-, Ca2+, Mg2+), suggesting that agriculture enriched fertilizer-associated nutrients in streamwater. The watershed with the highest proportion of agricultural lands had higher concentrations of ions in rainfall and lower nutrient retention capacity (i.e. higher output-input ratio of ions) compared to the relatively pristine watershed, suggesting that agriculture can influence atmospheric deposition of nutrients and a system's ability to retain nutrients. Furthermore, we found that a forested watershed downstream of agricultural activities can dilute the concentrations of fertilizer-associated ions (NO3-, K+) in streamwater by more than 70%, indicating that specific landscape configurations help mitigate nutrient enrichment to aquatic systems. We estimated that agricultural lands at our study site contributed approximately 400 kg ha-1 yr-1 of NO3-N and 260 kg ha-1 yr-1 of PO4-P output via streamwater, an order of magnitude greater than previously reported around the globe and can only be matched by areas under intense fertilizer use. Furthermore, we re-constructed watershed nutrient fluxes to show that excessive leaching of N and P, and additional loss of N to the atmosphere via volatilization and denitrification, can occur under intense fertilizer use. In summary, this study demonstrated the pervasive impacts of agriculture activities

  2. California's forest resources. Preliminary assessment

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    This Preliminary Assessment was prepared in response to the California Forest Resources Assessment and Policy Act of 1977 (FRAPA). This Act was passed to improve the information base upon which State resource administrators formulate forest policy. The Act provides for this report and a full assessment by 1987 and at five year intervals thereafter. Information is presented under the following chapter titles: introduction to the forest resources assessment program; the forest area: a general description; classifications of the forest lands; the watersheds; forest lands and the air resource; fish and wildlife resources; the forested rangelands; the wilderness; forest lands as a recreation resource; the timber resource; wood energy; forest lands and the mineral, fossil fuels, and geothermal energy resources; mathematically modeling California's forest lands; vegetation mapping using remote sensing technology; important forest resources legislation; and, State and cooperative State/Federal forestry programs. Twelve indexes, a bibliography, and glossary are included. (JGB)

  3. Spatial complementarity of forests and farms: accounting for ecosystem services

    Science.gov (United States)

    Subhrendu K. Pattanayak; David T. Butry

    2006-01-01

    Our article considers the economic contributions of forest ecosystem services, using a case study from Flores, Indonesia, in which forest protection in upstream watersheds stabilize soil and hydrological flows in downstream farms. We focus on the demand for a weak complement to the ecosystem services--farm labor-- and account for spatial dependence due to economic...

  4. Assessing the Impact of Landscape Development on Ecosystem Services Value in Tropical Watershed

    Science.gov (United States)

    Foo, Y. S.; Hashim, M.

    2014-02-01

    As development increases with demand, more forest lands are replaced with cropland, commercial plantation, and infrastructures for being able to accommodate the excessive growth in world's population. Environments were destroyed without considering their values in sustaining life on Earth.This phenomenon is still an ongoing scenario in most of the developing countries in the tropical region including Malaysia. Such unrestricted conversion may cause food or water crisis along with irreparable consequences to local and regional climate as the natural ecosystem is not only the main resources generator but also the climate stabilizer. Contrary to this, a study was conducted in Pahang Watershed, the largest watershed in Peninsular Malaysia with forest as the dominant land cover, to investigate the effect of landscape development on the ecosystem in terms of the erosion and ecosystem service value. Results of soil loss based on USLE indicated a direct relationship between development and total soil loss where total annual soil loss in year 2005 and 2010 showed a significant increase compare to year 2000. Meanwhile, developed and agricultural lands were discovered to be the main contributor whereas forest land produce the least soil loss (oil palm had become the main commercial plantation in current years, the commercial profit brought by oil palm still insufficient to cover losses referring to overall estimated ESVG due to the forest clearance and soil degradation. In addition, for a destroyed ecosystem to be equilibrium again requires years. Therefore, ESVG of the tropical forest are expected to increase continuously in future which mean that the roles of the forest in conserving the environment stabilization and sustainability of life are getting more critical.

  5. Land Capability Evaluation of Upper Sekampung Watersheds

    Directory of Open Access Journals (Sweden)

    Irwan Sukri Banuwa

    2008-05-01

    Full Text Available Land degradation is a serious problem in the Upper Sekampung Watersheds. This is because the farmers cultivated in steep land to coffee crops without in adequate soil and water conservation practices. The land degradation is mostly caused by erosion. The erosion problem not only stripping the most fertile top soil and decreasing crop production, but also resulting problems in lowland. Therefore, the reorientation land management should be improved to produce agriculture sustainability. The first step is to evaluated land capability this area. The objectives of the research were evaluate land capability of Upper Sekampung Watersheds. The results showed that the Upper Sekampung Watersheds were dominated with class and subclass land capability of III-l2 about 17.630,51 ha (41,58%. All of the constrain for each land capability in this area is erosion hazard, especially land slope. From this research, cultivated land to coffee base crops were allowed in land capability II-l1.e1, III-l2, IV-l3, and VI-l4, with in adequate soil and water conservation practices. In contrary, the land capability of VII-l5 unsuitable for agriculture, they should be a nature or for conservation forest.

  6. Runoff water quality from a sierran upland forest, transition ecotone, and riparian wet meadow

    Science.gov (United States)

    High concentrations of inorganic N, P, and S have been reported in overland and litter interflow within forested uplands of the Tahoe basin and surrounding watersheds. In this study we compared runoff nutrient concentration and load as well as soil nutrient fluxes at three watershed locations; an up...

  7. Declines in soil-water nitrate in nitrogen-saturated watersheds

    Science.gov (United States)

    Pamela J. Edwards; Karl W. J. Williard

    2006-01-01

    Two forested watersheds (WS3 and WS9) in the central Appalachians were artificially acidified with ammonium sulfate fertilizer. WS9 was treated for 8 years, whereas WS3 has been treated for approximately 15 years. Soil leachate was collected from a depth of 46 cm (B horizon) in WS9 and below the A, B, and C horizons in WS3. Nitrate concentrations from WS3 increased for...

  8. Rapid Assessment of Logging-Associated Sediment-Delivery Pathways in an Intensively-Managed Forested Watershed in the Southern Cascades, Northern California

    Science.gov (United States)

    Coe, D. B.; Wopat, M. A.; Lindsay, D.; Stanish, S.; Boone, M.; Beck, B.; Wyman, A.; Bull, J.

    2012-12-01

    The potential for water-quality impacts in intensively-managed forested watersheds depends partly upon the frequency of overland flow paths linking logging-related hillslope sediment sources to the channel network, as well as the volume of sediment delivered along these flow paths. In response to public concerns over perceived water-quality impacts from clearcut timber harvesting, the Battle Creek Task Force, composed of subject-matter experts from 4 different state agencies, performed a rapid assessment for visible evidence of sediment delivery pathways from multiple logging-associated features in the upper Battle Creek watershed - an area underlain predominantly by Holocene- and Late Pleistocene-aged volcanic rock types, with highly permeable soils, and relatively few streams. Logging-associated features were selected for assessment based on erosion potential and proximity to stream channels. Identified sediment-delivery pathways were then characterized by dominant erosion process and the relative magnitude of sediment delivery (i.e., low, moderate, and high) was estimated. Approximately 26 km of stream buffers adjacent to 55 clearcut harvest units were assessed, and the single detected instance of sediment delivery was found to be of low magnitude and the result of illegal encroachment by logging equipment into a 5-m wide stream-adjacent equipment-limitation zone. The proportion of sampled sites delivering sediment was found to be highest for tractor-stream crossings, followed by road-stream crossings, stream-adjacent road segments, stream-adjacent landings, and clearcut harvest units, respectively. All 5 tractor-stream crossings delivered sediment, but were generally delivering a low magnitude of sediment derived from sheetwash and rilling. Road-stream crossings (n=39) and stream-adjacent road segments (n=24) delivered observable sediment 69 and 67 percent of the time, respectively. The highest magnitudes of sediment delivery from roads were associated with

  9. Characterization of suspended solids and total phosphorus loadings from small watersheds in Wisconsin

    Science.gov (United States)

    Danz, Mari E.; Corsi, Steven R.; Graczyk, David J.; Bannerman, Roger T.

    2010-01-01

    Knowledge of the daily, monthly, and yearly distribution of contaminant loadings and streamflow can be critical for the successful implementation and evaluation of water-quality management practices. Loading data for solids (suspended sediment and total suspended solids) and total phosphorus and streamflow data for 23 watersheds were summarized for four ecoregions of Wisconsin: the Driftless Area Ecoregion, the Northern Lakes and Forests Ecoregion, the North Central Hardwoods Ecoregion, and the Southeastern Wisconsin Till Plains Ecoregion. The Northern Lakes and Forests and the North Central Hardwoods Ecoregions were combined into one region for analysis due to a lack of sufficient data in each region. Urban watersheds, all located in the Southeastern Wisconsin Till Plains, were analyzed separately from rural watersheds as the Rural Southeastern Wisconsin Till Plains region and the Urban Southeastern Wisconsin Till Plains region. Results provide information on the distribution of loadings and streamflow between base flow and stormflow, the timing of loadings and streamflow throughout the year, and information regarding the number of days in which the majority of the annual loading is transported. The average contribution to annual solids loading from stormflow periods for the Driftless Area Ecoregion was 84 percent, the Northern Lakes and Forests/North Central Hardwoods region was 71 percent, the Rural Southeastern Wisconsin Till Plains region was 70 percent, and the Urban Southeastern Wisconsin Till Plains region was 90 percent. The average contributions to annual total phosphorus loading from stormflow periods were 72, 49, 61, and 76 percent for each of the respective regions. The average contributions to annual streamflow from stormflow periods are 20, 23, 31, and 50 percent for each of the respective regions. In all regions, the most substantial loading contributions for solids were in the late winter (February through March), spring (April through May), and

  10. Effects of mountain tea plantations on nutrient cycling at upstream watersheds

    Science.gov (United States)

    Lin, T.-C.; Shaner, P.-J. L.; Wang, L.-J.; Shih, Y.-T.; Wang, C.-P.; Huang, G.-H.; Huang, J.-C.

    2015-11-01

    The expansion of agriculture to rugged mountains can exacerbate negative impacts of agricultural activities on ecosystem function. In this study, we monitored streamwater and rainfall chemistry of mountain watersheds at the Feitsui Reservoir Watershed in northern Taiwan to examine the effects of agriculture on watershed nutrient cycling. We found that the greater the proportion of tea plantation cover, the higher the concentrations of fertilizer-associated ions (NO3-, K+) in streamwater of the four mountain watersheds examined; on the other hand, the concentrations of the ions that are rich in soils (SO42-, Ca2+, Mg2+) did not increase with the proportion of tea plantation cover, suggesting that agriculture enriched fertilizer-associated nutrients in streamwater. Of the two watersheds for which rainfall chemistry was available, the one with higher proportion of tea plantation cover had higher concentrations of ions in rainfall and retained less nitrogen in proportion to input compared to the more pristine watershed, suggesting that agriculture can influence atmospheric deposition of nutrients and a system's ability to retain nutrients. As expected, we found that a forested watershed downstream of agricultural activities can dilute the concentrations of NO3- in streamwater by more than 70 %, indicating that such a landscape configuration helps mitigate nutrient enrichment in aquatic systems even for watersheds with steep topography. We estimated that tea plantation at our study site contributed approximately 450 kg ha-1 yr-1 of NO3-N via streamwater, an order of magnitude greater than previously reported for agricultural lands around the globe, which can only be matched by areas under intense fertilizer use. Furthermore, we constructed watershed N fluxes to show that excessive leaching of N, and additional loss to the atmosphere via volatilization and denitrification can occur under intense fertilizer use. In summary, this study demonstrated the pervasive impacts of

  11. Effect of forest harvesting best management practices on coarse woody debris distribution in stream and riparian zones in three Appalachian watersheds

    Science.gov (United States)

    J. M. McClure; R. K. Kolka; A. White

    2004-01-01

    The distribution of coarse woody debris (CWD) was analyzed in three Appalachian watersheds in eastern Kentucky, eighteen years after harvest. The three watersheds included an unharvested control (Control), a second watershed with best management practices (BMPs) applied that included a 15.2 m unharvested zone near the stream (BMP watershed), and a third watershed that...

  12. Physical characterization of a watershed through GIS: a study in the Schmidt stream, Brazil.

    Science.gov (United States)

    Reis, D R; Plangg, R; Tundisi, J G; Quevedo, D M

    2015-12-01

    Remote sensing and geoprocessing are essential tools for obtaining and maintaining records of human actions on space over the course of time; these tools offer the basis for diagnoses of land use, environmental interference and local development. The Schmidt stream watershed, located in the Sinos River basin, in southern Brazil, has an environmental situation similar to that of the majority of small streams draining rural and urban areas in southern Brazil: agricultural and urbanization practices do not recognize the riparian area and there is removal of original vegetation, disregarding the suitability of land use; removal of wetlands; intensive water use for various activities; and lack of control and monitoring in the discharge of wastewater, among other factors, deteriorate the quality of this important environment.This article aims to achieve a physical characterization of the Schmidt stream watershed (Sinos river basin) identifying elements such as land use and occupation, soil science, geology, climatology, extent and location of watershed, among others, so as to serve as the basis for a tool that helps in the integrated environmental management of watersheds. By applying geographic information system - GIS to the process of obtaining maps of land use and occupation, pedologicaland geological, and using climatological data from the Campo Bom meteorological station, field visit, review of literature and journals, and publicly available data, the physical characterization of the Schmidt stream watershed was performed, with a view to the integrated environmental management of this watershed. Out of the total area of the Schmidt stream watershed (23.92 km(2)), in terms of geology, it was observed that 23.7% consist of colluvial deposits, 22.6% consist of grass facies, and 53.7% consist of Botucatu formation. Major soil types of the watershed: 97.4% Argisols and only 2.6% Planosols. Land use and occupation is characterized by wetland (0.5%), Native Forest (12

  13. Developing a Forest Health Index for public engagement and decision support using local climatic, ecological, and socioeconomic data

    Science.gov (United States)

    Arnott, J. C.; Katzenberger, J.; Cundiff, J.

    2013-12-01

    Forest health is an oft-used term without a generally accepted definition. Nonetheless, the concept of forest health continues to permeate scientific, resource management, and public discourse, and it is viewed as a helpful communication device for engagement on issues of concern to forests and their surrounding communities. Notwithstanding the challenges associated with defining the concept of 'forest health,' we present a model for assessing forest health at a watershed scale. Utilizing the Roaring Fork Valley, Colorado--a mountain watershed of 640,000 forested acres--as a case study, we have created a Forest Health Index that integrates a range of climatic, ecological, and socioeconomic data into an assessment organized along a series of public goals including, 1) Ecosystem Services, 2) Public Health & Safety, 3) Sustainable Use & Management, and 4) Ecological Integrity. Methods for this index were adopted from an earlier effort called the Ocean Health Index by Halpern et al, 2012. Indicators that represent drivers of change, such as temperature and precipitation, as well as effects of change, such as primary productivity and phenology, were selected. Each indicator is assessed by comparing a current status of that indicator to a reference scenario obtained through one of the following methods: a) statistical analysis of baseline data from the indicator record, b) commonly accepted normals, thresholds, limits, concentrations, etc., and c) subjective expert judgment. The result of this assessment is a presentation of graphical data and accompanying ratings that combine to form an index of health for the watershed forest ecosystem. We find this product to have potential merit for communities working to assess the range of conditions affecting forest health as well as making sense of the outcomes of those affects. Here, we present a description of the index methodology, data results from engagement with forest watershed stakeholders, example results of data

  14. Effect of assessment scale on spatial and temporal variations in CH4, C02, and N20 fluxes in a forested wetland

    Science.gov (United States)

    Zhaohua Dai; Carl Trettin; Changsheng Li; Harbin Li; Ge Sun; Devendra Amatya

    2011-01-01

    Emissions of methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O) from a forested watershed (160 ha) in South Carolina, USA, were estimated with a spatially explicit watershed-scale modeling framework that utilizes the spatial variations in physical and biogeochemical characteristics across watersheds. The target watershed (WS80) consisting of wetland (23%) and...

  15. Short-term responses to watershed logging on biomass mercury and methylmercury accumulation by periphyton in boreal lakes

    Energy Technology Data Exchange (ETDEWEB)

    Desrosiers, M.; Planas, D. [Quebec Univ., Montreal, PQ (Canada). Dept. de sciences biologiques; Mucci, A. [McGill Univ., Montreal, PQ (Canada). Dept. of Earth and Planetary Sciences

    2006-08-15

    Increased timber harvesting in the boreal regions of Quebec may have a significant impact on aquatic ecosystems. Watershed disturbances such as logging increase chemical loading to lakes. Soil in the Canadian Shield readily adsorbs and accumulates mercury (Hg) from atmospheric deposition. Forest watersheds serve as large reservoirs of Hg that shed their metal load when soil and land hydrology are disrupted. This paper presented the results of a study evaluating the impact of logging on periphyton algal biomass and dry mass. The study also evaluated the impact of total mercury (THG) and methylmercury (MeHg) accumulation in the littoral zone of the boreal lakes. A before-after control-impact (BACI) sample design was applied that required data from control and target sites sampled both before and after the disturbances. The study was carried out on 18 boreal lakes located in the Grenville geological province. Eight lakes had their watersheds logged over 15 to 79 per cent of their area. A further 10 lakes were used as control sites to document interannual variations. The project used water quality and physiographic data acquired by research groups within the Sustainable Forest Management Network. Fourteen study lakes were sampled once a year during 2 consecutive ice-free seasons before and after logging, and another 4 lakes were sampled 2 years after logging. Significant decreases in algal biomass and increases in MeHg concentrations in periphyton mats in a majority of the harvested watershed lakes were detected. The increases may have a significant impact on organisms of higher trophic levels as they are at the base of the food web. Results suggested that the observed decrease in periphyton biomass combined with the increase in MeHg accumulation may magnify the impact of logging activities on fish and other aquatic predators. Two years after logging, it was observed that MeHg concentrations were still increasing. It was concluded that further research is needed

  16. Multidimensional Scaling Approach to Evaluate the Level of Community Forestry Sustainability in Babak Watershed, Lombok Island, West Nusa Tenggara

    Directory of Open Access Journals (Sweden)

    Ryke Nandini

    2017-07-01

    Full Text Available Community forestry in Babak watershed is one of the efforts to reduce critical land area. The aim of this research was to evaluate the level of community forestry sustainability in both of community forest (HKm and private forest in Babak watershed. Multidimensional scaling (MDS was used to analyse the level of community forest sustainability based on the five dimensions of ecology, economy, social, institutional, and technology as well as 29 attributes. Leverage analysis was used to know the sensitive attributes of sustainability, while Monte Carlo analysis and goodness of fit was used to find the accuracy of MDS analysis. The result shows that HKm was in moderate sustainability level (sustainability index 54.08% and private forest was in less sustainability level (sustainability index 48.53%. Furthermore, the ecology and technology in HKm were classified as less sustainable, while the institution and technology in private forest were considered less sustainable. There were 11 sensitive attributes of HKm and 19 sensitive attributes of private forest. The priorities of attribute improvement in HKm include land recovering (the dimension of ecology and cooperative development (the dimension of technology. In private forest, the priorities of attribute improvement include leadership capacity building (the institutional dimension and also the use of silviculture intensive and soil conservation (the dimension of technology.

  17. Effects of drainage-basin geomorphology on insectivorous bird abundance in temperate forests.

    Science.gov (United States)

    Iwata, Tomoya; Urabe, Jotaro; Mitsuhashi, Hiromune

    2010-10-01

    Interfaces between terrestrial and stream ecosystems often enhance species diversity and population abundance of ecological communities beyond levels that would be expected separately from both the ecosystems. Nevertheless, no study has examined how stream configuration within a watershed influences the population of terrestrial predators at the drainage-basin scale. We examined the habitat and abundance relationships of forest insectivorous birds in eight drainage basins in a cool temperate forest of Japan during spring and summer. Each basin has different drainage-basin geomorphology, such as the density and frequency of stream channels. In spring, when terrestrial arthropod prey biomass is limited, insectivorous birds aggregated in habitats closer to streams, where emerging aquatic prey was abundant. Nevertheless, birds ceased to aggregate around streams in summer because terrestrial prey became plentiful. Watershed-scale analyses showed that drainage basins with longer stream channels per unit area sustained higher densities of insectivorous birds. Moreover, such effects of streams on birds continued from spring through summer, even though birds dispersed out of riparian areas in the summer. Although our data are from only a single year, our findings imply that physical modifications of stream channels may reduce populations of forest birds; thus, they emphasize the importance of landscape-based management approaches that consider both stream and forest ecosystems for watershed biodiversity conservation. © 2010 Society for Conservation Biology.

  18. Evolution of soil, ecosystem, and critical zone research at the USDA FS Calhoun Experimental Forest

    Science.gov (United States)

    Daniel deB. Richter; Allan R. Bacon; Sharon A. Billings; Dan Binkley; Marilyn Buford; Mac Callaham; Amy E. Curry; Ryan L. Fimmen; A. Stuart Grandy; Paul R. Heine; Michael Hofmockel; Jason A. Jackson; Elisabeth LeMaster; Jianwei Li; Daniel Markewitz; Megan L. Mobley; Mary W. Morrison; Michael S. Strickland; Thomas Waldrop; Carol G. Wells

    2015-01-01

    The US Department of Agriculture (USDA) Forest Service Calhoun Experimental Forest was organized in 1947 on the southern Piedmont to engage in research that today is called restoration ecology, to improve soils, forests, and watersheds in a region that had been severely degraded by nearly 150 years farming. Today, this 2,050-ha research forest is managed by the Sumter...

  19. stream nutrient uptake, forest succession, and biogeochemical theory

    OpenAIRE

    Valett, H. M.; Crenshaw, C. L.; Wagner, P. F.

    2002-01-01

    Theories of forest succession predict a close relationship between net biomass increment and catchment nutrient retention. Retention, therefore, is expected to be greatest during aggrading phases of forest succession. In general, studies of this type have compared watershed retention efficiency by monitoring stream nutrient export at the base of the catchment. As such, streams are viewed only as transport systems. Contrary to this view, the nutrient spiraling concept emphasizes transformation...

  20. Baseline for Climate Change: Modeling Watershed Aquatic Biodiversity Relative to Environmental and Anthropogenic Factors

    Energy Technology Data Exchange (ETDEWEB)

    Maurakis, Eugene G

    2010-10-01

    Objectives of the two-year study were to (1) establish baselines for fish and macroinvertebrate community structures in two mid-Atlantic lower Piedmont watersheds (Quantico Creek, a pristine forest watershed; and Cameron Run, an urban watershed, Virginia) that can be used to monitor changes relative to the impacts related to climate change in the future; (2) create mathematical expressions to model fish species richness and diversity, and macroinvertebrate taxa and macroinvertebrate functional feeding group taxa richness and diversity that can serve as a baseline for future comparisons in these and other watersheds in the mid-Atlantic region; and (3) heighten people’s awareness, knowledge and understanding of climate change and impacts on watersheds in a laboratory experience and interactive exhibits, through internship opportunities for undergraduate and graduate students, a week-long teacher workshop, and a website about climate change and watersheds. Mathematical expressions modeled fish and macroinvertebrate richness and diversity accurately well during most of the six thermal seasons where sample sizes were robust. Additionally, hydrologic models provide the basis for estimating flows under varying meteorological conditions and landscape changes. Continuations of long-term studies are requisite for accurately teasing local human influences (e.g. urbanization and watershed alteration) from global anthropogenic impacts (e.g. climate change) on watersheds. Effective and skillful translations (e.g. annual potential exposure of 750,000 people to our inquiry-based laboratory activities and interactive exhibits in Virginia) of results of scientific investigations are valuable ways of communicating information to the general public to enhance their understanding of climate change and its effects in watersheds.

  1. Tracking geomorphic signatures of watershed suburbanization with multi-temporal LiDAR

    Science.gov (United States)

    Jones, Daniel K.; Baker, Matthew E.; Miller, Andrew J.; Jarnagin, S. Taylor; Hogan, Dianna M.

    2014-01-01

    Urban development practices redistribute surface materials through filling, grading, and terracing, causing drastic changes to the geomorphic organization of the landscape. Many studies document the hydrologic, biologic, or geomorphic consequences of urbanization using space-for-time comparisons of disparate urban and rural landscapes. However, no previous studies have documented geomorphic changes from development using multiple dates of high-resolution topographic data at the watershed scale. This study utilized a time series of five sequential light detection and ranging (LiDAR) derived digital elevation models (DEMs) to track watershed geomorphic changes within two watersheds throughout development (2002–2008) and across multiple spatial scales (0.01–1 km2). Development-induced changes were compared against an undeveloped forested watershed during the same time period. Changes in elevations, slopes, hypsometry, and surface flow pathways were tracked throughout the development process to assess watershed geomorphic alterations. Results suggest that development produced an increase in sharp topographic breaks between relatively flat surfaces and steep slopes, replacing smoothly varying hillslopes and leading to greater variation in slopes. Examinations of flowpath distributions highlight systematic modifications that favor rapid convergence in unchanneled upland areas. Evidence of channel additions in the form of engineered surface conduits is apparent in comparisons of pre- and post-development stream maps. These results suggest that topographic modification, in addition to impervious surfaces, contributes to altered hydrologic dynamics observed in urban systems. This work highlights important considerations for the use of repeat LiDAR flights in analyzing watershed change through time. Novel methods introduced here may allow improved understanding and targeted mitigation of the processes driving geomorphic changes during development and help guide future

  2. Influences of forest and rangeland management on salmonid fishes and their habitats

    National Research Council Canada - National Science Library

    Meehan, William R

    1991-01-01

    Contents : Stream ecosystems - Salmonid distributions and life histories - Habitat requirements of salmonids in streams - Natural processes - Timber harvesting, silvicultrue and watershed processes - Forest...

  3. Forest-related ecosystem services

    Science.gov (United States)

    Sandra Luque; Louis Iverson

    2016-01-01

    Forests are a crucial element not only of landscapes but also of human living conditions. Covering nearly a third of the earth's land surtace, they stabilize surface soil, prevent erosion and play an essential role in water resource management at the watershed and local levels. They regulate climate and improve air quality. At the same time they are an important...

  4. Normalized difference vegetation index (ndvi) analysis for land cover types using landsat 8 oli in besitang watershed, Indonesia

    Science.gov (United States)

    Zaitunah, A.; Samsuri; Ahmad, A. G.; Safitri, R. A.

    2018-03-01

    Watershed is an ecosystem area confined by topography and has function as a catcher, storage, and supplier of water, sediments, pollutants and nutrients in the river system and exit through a single outlet. Various activities around watershed areas of Besitang have changed the land cover and vegetation index (NDVI) that exist in the region. In order to detect changes in land cover and NDVI quickly and accurately, we used remote sensing technology and geographic information systems (GIS). The study aimed to assess changes in land cover and vegetation density (NDVI) between 2005 and 2015, as well as obtaining the density of vegetation (NDVI) on each of the land cover of 2005 and 2015. The research showed the extensive of forest area of 949.65 Ha and a decline of mangrove forest area covering an area of 2,884.06 Ha. The highest vegetation density reduced 39,714.58 Ha, and rather dense increased 24,410.72 Ha between 2005 and 2015. The land cover that have the highest NDVI value range with very dense vegetation density class is the primary dry forest (0.804 to 0.876), followed by secondary dry forest (0.737 to 0.804) for 2015. In 2015 the land cover has NDVI value range the primary dry forest (0.513 to 0.57), then secondary dry forest (0.456 to 0.513) with dense vegetation density class

  5. A baseline and watershed assessment in the Lynx Creek, Brenot Creek, and Portage Creek watersheds near Hudson's Hope, BC : summary report

    International Nuclear Information System (INIS)

    Matscha, G.; Sutherland, D.

    2005-06-01

    This report summarized a baseline monitoring program for the Lynx Creek, Brenot Creek, and Portage Creek watersheds located near Hudson's Hope, British Columbia (BC). The monitoring program was designed to more accurately determine the effects of potential coalbed gas developments in the region, as well as to assess levels of agricultural and forest harvesting, and the impacts of current land use activities on water quantity and quality. Water quality was sampled at 18 sites during 5 different flow regimes, including summer and fall low flows; ice cover; spring run-off; and high flows after a heavy summer rain event. Sample sites were located up and downstream of both forest and agricultural activities. The water samples were analyzed for 70 contaminants including ions, nutrients, metals, hydrocarbons, and hydrocarbon fractions. Results showed that while many analyzed parameters met current BC water quality guidelines, total organic carbon, manganese, cadmium, E. coli, fecal coliforms, and fecal streptococci often exceeded recommended guidelines. Aluminum and cobalt values exceeded drinking water guidelines. The samples also had a slightly alkaline pH and showed high conductance. A multiple barrier approach was recommended to reduce potential risks of contamination from the watersheds. It was concluded that a more refined bacteria source tracking method is needed to determine whether fecal pollution has emanated from human, livestock or wildlife sources. 1 tab., 9 figs

  6. Water, Energy and Carbon Balance Research: Recovery Trajectories For Oil Sands Reclamation and Disturbed Watersheds in the Western Boreal Forest

    Science.gov (United States)

    Petrone, R. M.; Carey, S. K.

    2014-12-01

    The Oil Sand Region (OSR) of North-Central Alberta exists within the sub-humid Boreal Plains (BP) ecozone, with a slight long-term moisture deficit regime. Despite this deficit, the BP is comprised of productive wetland and mixed wood (aspen and conifer dominated) forests. Reclamation activities are now underway at a large number of surface mining operations in the OSR, where target ecosystems are identified, soil prescriptions placed and commercial forest species planted. Some watersheds have been created that now contain wetlands. However, recent work in the BP suggests that over time wetlands supply moisture for the productivity of upland forests. Thus, water use of reclaimed forests is going to be critical in determining the sustainability of these systems and adjacent wetlands, and whether in time, either will achieve some form of equivalent capability that will allow for certification by regulators. A critical component in the success of any reclamation is that sufficient water is available to support target ecosystems through the course of natural climate cycles in the region. Water Use Efficiency (WUE), which links photosynthesis (GEP) with water use (Evapotranspiration (ET)), provides a useful metric to compare ecosystems and evaluate their utilization of resources. In this study, 41 site years of total growing season water and carbon flux data over 8 sites (4 reclamation, 4 regeneration) were evaluated using eddy covariance micrometeorological towers. WUE shows clear discrimination among ecosystem types as aspen stands assimilate more carbon per unit weight of water than conifers. WUEs also change with time as ecosystems become more effective at transpiring water through plant pathways compared with bare-soil evaporation, which allows an assessment of ability to limit water loss without carbon uptake. In addition, clonal rooting systems allow aspen forests to recover quicker after disturbance than reclamation sites in terms of their WUE. For reclamation

  7. Assessing the Impact of Landscape Development on Ecosystem Services Value in Tropical Watershed

    International Nuclear Information System (INIS)

    Foo, Y S; Hashim, M

    2014-01-01

    As development increases with demand, more forest lands are replaced with cropland, commercial plantation, and infrastructures for being able to accommodate the excessive growth in world's population. Environments were destroyed without considering their values in sustaining life on Earth.This phenomenon is still an ongoing scenario in most of the developing countries in the tropical region including Malaysia. Such unrestricted conversion may cause food or water crisis along with irreparable consequences to local and regional climate as the natural ecosystem is not only the main resources generator but also the climate stabilizer. Contrary to this, a study was conducted in Pahang Watershed, the largest watershed in Peninsular Malaysia with forest as the dominant land cover, to investigate the effect of landscape development on the ecosystem in terms of the erosion and ecosystem service value. Results of soil loss based on USLE indicated a direct relationship between development and total soil loss where total annual soil loss in year 2005 and 2010 showed a significant increase compare to year 2000. Meanwhile, developed and agricultural lands were discovered to be the main contributor whereas forest land produce the least soil loss (<10ton/ ha/yr). Apart from this, this study also reports a degrading trend in the overall ecological service value and goods (ESVG). Although oil palm had become the main commercial plantation in current years, the commercial profit brought by oil palm still insufficient to cover losses referring to overall estimated ESVG due to the forest clearance and soil degradation. In addition, for a destroyed ecosystem to be equilibrium again requires years. Therefore, ESVG of the tropical forest are expected to increase continuously in future which mean that the roles of the forest in conserving the environment stabilization and sustainability of life are getting more critical

  8. The role of forest humus in watershed management in New England

    Science.gov (United States)

    G. R., Jr. Trimble; Howard W. Lull

    1956-01-01

    Forest humus is one of the most interesting components of the forest environment. Its surface serves as a depository for leaf fall and needle fall, with successive depths marking stages of transmutation from the freshly fallen to the decomposed. And humus is responsive: humus type and depth are indicators of forest treatment and, to some extent, of site quality....

  9. Tree and forest water use under elevated CO2 and temperature in Scandinavian boreal forest

    Science.gov (United States)

    Berg Hasper, Thomas; Wallin, Göran; Lamba, Shubhangi; Sigurdsson, Bjarni D.; Laudon, Hjalmar; Medhurst, Jane L.; Räntfors, Mats; Linder, Sune; Uddling, Johan

    2014-05-01

    According to experimental studies and models, rising atmospheric carbon dioxide concentration ([CO2]) and temperature have the potential to affect stomatal conductance and, consequently, tree and forest transpiration. This effect has in turn the capacity to influence the terrestrial energy and water balance, including affecting of the magnitude of river runoff. Furthermore, forest productivity is currently water-limited in southern Scandinavia and in a near future, under the projected climatic change, this limitation may become a reality in the central and northern parts of Scandinavia. In this study we examine the water-use responses in 12 40-year old native boreal Norway spruce (Picea abies (L.) Karst.) trees exposed to a factorial combination of two levels of [CO2] (ambient and doubled) and temperature (ambient and +2.8 °C in summer / +5.6 °C in winter), as well as of entire boreal forests to temporal variation in [CO2], temperature and precipitation over the past 50 years in central and northern Sweden. The controlled factorial CO2 and temperature whole-tree chamber experiment at Flakaliden study site demonstrated that Norway spruce trees lacked elevated [CO2]-induced water savings at guard cell, shoot, and tree levels in the years of measurements. Experimentally, elevated temperature did not result in increased shoot or tree water use as stomatal closure fully cancelled the effect of higher vapour pressure deficit in warmed air environment. Consistent with these results, large scale river runoff data and evapotranspiration estimates from large forested watersheds in central Sweden supported lack of elevated CO2-mediated water savings, and rather suggested that the increasing evapotranspiration trend found in this study was primarily linked to increasing precipitation, rising temperature and more efficient forest management. The results from the whole-tree chamber experiment and boreal forested watersheds have important implications for more accurate

  10. Evaluating sources and processing of nonpoint source nitrate in a small suburban watershed in China

    Science.gov (United States)

    Han, Li; Huang, Minsheng; Ma, Minghai; Wei, Jinbao; Hu, Wei; Chouhan, Seema

    2018-04-01

    Identifying nonpoint sources of nitrate has been a long-term challenge in mixed land-use watershed. In the present study, we combine dual nitrate isotope, runoff and stream water monitoring to elucidate the nonpoint nitrate sources across land use, and determine the relative importance of biogeochemical processes for nitrate export in a small suburban watershed, Longhongjian watershed, China. Our study suggested that NH4+ fertilizer, soil NH4+, litter fall and groundwater were the main nitrate sources in Longhongjian Stream. There were large changes in nitrate sources in response to season and land use. Runoff analysis illustrated that the tea plantation and forest areas contributed to a dominated proportion of the TN export. Spatial analysis illustrated that NO3- concentration was high in the tea plantation and forest areas, and δ15N-NO3 and δ18O-NO3 were enriched in the step ponds. Temporal analysis showed high NO3- level in spring, and nitrate isotopes were enriched in summer. Study as well showed that the step ponds played an important role in mitigating nitrate pollution. Nitrification and plant uptake were the significant biogeochemical processes contributing to the nitrogen transformation, and denitrification hardly occurred in the stream.

  11. Wind River Watershed restoration: 1999 annual report; ANNUAL

    International Nuclear Information System (INIS)

    Connolly, Patrick J.

    2001-01-01

    This document represents work conducted as part of the Wind River Watershed Restoration Project during its first year of funding through the Bonneville Power Administration (BPA). The project is a comprehensive effort involving public and private entities seeking to restore water quality and fishery resources in the basin through cooperative actions. Project elements include coordination, watershed assessment, restoration, monitoring, and education. Entities involved with implementing project components are the Underwood Conservation District (UCD), USDA Forest Service (USFS), U.S. Geological Survey-Columbia River Research Lab (USGS-CRRL), and WA Department of Fish and Wildlife (WDFW). Following categories given in the FY1999 Statement of Work, the broad categories, the related objectives, and the entities associated with each objective (lead entity in boldface) were as follows: Coordination-Objective 1: Coordinate the Wind River watershed Action Committee (AC) and Technical Advisory Committee (TAC) to develop a prioritized list of watershed enhancement projects. Monitoring-Objective 2: Monitor natural production of juvenile, smolt, and adult steelhead in the Wind River subbasin. Objective 3: Evaluate physical habitat conditions in the Wind River subbasin. Assessment-Objective 4: Assess watershed health using an ecosystem-based diagnostic model that will provide the technical basis to prioritize out-year restoration projects. Restoration-Objective 5: Reduce road related sediment sources by reducing road densities to less than 2 miles per square mile. Objective 6: Rehabilitate riparian corridors, flood plains, and channel morphology to reduce maximum water temperatures to less than 61 F, to increase bank stability to greater than 90%, to reduce bankfull width to depth ratios to less than 30, and to provide natural levels of pools and cover for fish. Objective 7: Maintain and evaluate passage for adult and juvenile steelhead at artificial barriers. Education

  12. Integrated Landsat Image Analysis and Hydrologic Modeling to Detect Impacts of 25-Year Land-Cover Change on Surface Runoff in a Philippine Watershed

    Directory of Open Access Journals (Sweden)

    Enrico Paringit

    2011-05-01

    Full Text Available Landsat MSS and ETM+ images were analyzed to detect 25-year land-cover change (1976–2001 in the critical Taguibo Watershed in Mindanao Island, Southern Philippines. This watershed has experienced historical modifications of its land-cover due to the presence of logging industries in the 1950s, and continuous deforestation due to illegal logging and slash-and-burn agriculture in the present time. To estimate the impacts of land-cover change on watershed runoff, land-cover information derived from the Landsat images was utilized to parameterize a GIS-based hydrologic model. The model was then calibrated with field-measured discharge data and used to simulate the responses of the watershed in its year 2001 and year 1976 land-cover conditions. The availability of land-cover information on the most recent state of the watershed from the Landsat ETM+ image made it possible to locate areas for rehabilitation such as barren and logged-over areas. We then created a “rehabilitated” land-cover condition map of the watershed (re-forestation of logged-over areas and agro-forestation of barren areas and used it to parameterize the model and predict the runoff responses of the watershed. Model results showed that changes in land-cover from 1976 to 2001 were directly related to the significant increase in surface runoff. Runoff predictions showed that a full rehabilitation of the watershed, especially in barren and logged-over areas, will be likely to reduce the generation of a huge volume of runoff during rainfall events. The results of this study have demonstrated the usefulness of multi-temporal Landsat images in detecting land-cover change, in identifying areas for rehabilitation, and in evaluating rehabilitation strategies for management of tropical watersheds through its use in hydrologic modeling.

  13. Studying dissolved organic carbon export from the Penobscot Watershed in to Gulf of Maine using Regional Hydro-Ecological Simulation System (RHESSys)

    Science.gov (United States)

    Rouhani, S. F. B. B.; Schaaf, C.; Douglas, E. M.; Choate, J. S.; Yang, Y.; Kim, J.

    2014-12-01

    The movement of Dissolved Organic Carbon (DOC) from terrestrial system into aquatic system plays an important role for carbon sequestration in ecosystems and affects the formation of soil organic matters.Carbon cycling, storage, and transport to marine systems have become critical issues in global-change science, especially with regard to northern latitudes (Freeman et al., 2001; Benner et al., 2004). DOC, as an important composition of the carbon cycling, leaches from the terrestrial watersheds is a large source of marine DOC. The Penobscot River basin in north-central Maine is the second largest watershed in New England, which drains in to Gulf of Maine. Approximately 89% of the watershed is forested (Griffith and Alerich, 1996).Studying temporal and spatial changes in DOC export can help us to understand terrestrial carbon cycling and to detect any shifts from carbon sink to carbon source or visa versa in northern latitude forested ecosystems.Despite for the importance of understanding carbon cycling in terrestrial and aquatic biogeochemistry, the Doc export, especially the combination of DOC production from bio-system and DOC transportation from the terrestrial in to stream has been lightly discussed in most conceptual or numerical models. The Regional Hydro-Ecological Simulation System (RHESSys), which has been successfully applied in many study sites, is a physical process based terrestrial model that has the ability to simulate both the source and transportation of DOC by combining both hydrological and ecological processes. The focus of this study is on simulating the DOC concentration and flux from the land to the water using RHESSys in the Penobscot watershed. The simulated results will be compared with field measurement of DOC from the watershed to explore the spatial and temporal DOC export pattern. This study will also enhance our knowledge to select sampling locations properly and also improve our understanding on DOC production and transportation in

  14. How are streamflow responses to the El Nino Southern Oscillation affected by watershed characteristics?

    Science.gov (United States)

    Rice, Joshua S.; Emanuel, Ryan E.

    2017-05-01

    Understanding the factors that influence how global climate phenomena, such as the El-Nino Southern Oscillation (ENSO), affect streamflow behavior is an important area of research in the hydrologic sciences. While large-scale patterns in ENSO-streamflow relationships have been thoroughly studied, and are relatively well-understood, information is scarce concerning factors that affect variation in ENSO responses from one watershed to another. To this end, we examined relationships between variability in ENSO activity and streamflow for 2731 watersheds across the conterminous U.S. from 1970 to 2014 using a novel approach to account for the intermediary role of precipitation. We applied an ensemble of regression techniques to describe relationships between variability in ENSO activity and streamflow as a function of watershed characteristics including: hydroclimate, topography, geomorphology, geographic location, land cover, soil characteristics, bedrock geology, and anthropogenic influences. We found that variability in watershed scale ENSO-streamflow relationships was strongly related to factors including: precipitation timing and phase, forest cover, and interactions between watershed topography and geomorphology. These, and other influential factors, share in common the ability to affect the partitioning and movement of water within watersheds. Our results demonstrate that the conceptualization of watersheds as signal filters for hydroclimate inputs, commonly applied to short-term rainfall-runoff responses, also applies to long-term hydrologic responses to sources of recurrent climate variability. These results also show that watershed processes, which are typically studied at relatively fine spatial scales, are also critical for understanding continental scale hydrologic responses to global climate.

  15. Accounting for small scale heterogeneity in ecohydrologic watershed models

    Science.gov (United States)

    Burke, W.; Tague, C.

    2017-12-01

    Spatially distributed ecohydrologic models are inherently constrained by the spatial resolution of their smallest units, below which land and processes are assumed to be homogenous. At coarse scales, heterogeneity is often accounted for by computing store and fluxes of interest over a distribution of land cover types (or other sources of heterogeneity) within spatially explicit modeling units. However this approach ignores spatial organization and the lateral transfer of water and materials downslope. The challenge is to account both for the role of flow network topology and fine-scale heterogeneity. We present a new approach that defines two levels of spatial aggregation and that integrates spatially explicit network approach with a flexible representation of finer-scale aspatial heterogeneity. Critically, this solution does not simply increase the resolution of the smallest spatial unit, and so by comparison, results in improved computational efficiency. The approach is demonstrated by adapting Regional Hydro-Ecologic Simulation System (RHESSys), an ecohydrologic model widely used to simulate climate, land use, and land management impacts. We illustrate the utility of our approach by showing how the model can be used to better characterize forest thinning impacts on ecohydrology. Forest thinning is typically done at the scale of individual trees, and yet management responses of interest include impacts on watershed scale hydrology and on downslope riparian vegetation. Our approach allow us to characterize the variability in tree size/carbon reduction and water transfers between neighboring trees while still capturing hillslope to watershed scale effects, Our illustrative example demonstrates that accounting for these fine scale effects can substantially alter model estimates, in some cases shifting the impacts of thinning on downslope water availability from increases to decreases. We conclude by describing other use cases that may benefit from this approach

  16. Interactions between payments for hydrologic services, landowner decisions, and ecohydrological consequences: synergies and disconnection in the cloud forest zone of central Veracruz, Mexico

    Directory of Open Access Journals (Sweden)

    Heidi Asbjornsen

    2017-06-01

    hydrologic services and people's decisions, behavior, and knowledge regarding forest conservation and water. Using central Veracruz as our case study, we identify areas of both synchrony and disconnection between PHS goals and outcomes. Mature and regenerating cloud forests (targeted by PHS were found to produce enhanced hydrologic services relative to areas converted to pasture, including reduced peak flows during large rain events and maintenance of dry-season base flows. However, unexpectedly, these hydrologic benefits from cloud forests were not necessarily greater than those from other vegetation types. Consequently, the location of forests in strategic watershed positions (e.g., where deforestation risk or hydrologic recharge are high may be more critical than forest type in promoting hydrologic functions within watersheds and should be considered when targeting PHS payments. While our results suggest that participation in PHS improved the level of knowledge among watershed inhabitants about forest-water relationships, a mismatch existed between payment amounts and landowner opportunity costs, which may contribute to the modest success in targeting priority areas within watersheds. Combined, these findings underscore the complexity of factors that influence motivations for PHS participation and land use decisions and behavior, and the importance of integrating understanding of both ecohydrological and socioeconomic dynamics into PHS design and implementation. We conclude by identifying opportunities for improving the design of PHS programs and recommending priority areas for future research and monitoring, both in Mexico and globally.

  17. Impact of urbanization on the sediment yield in tropical watershed using temporal land-use changes and a GIS-based model

    Directory of Open Access Journals (Sweden)

    Bello Al-Amin D.

    2017-09-01

    Full Text Available Abundant rainfall areas promote sediment yield at both sub-watershed and watershed scale due to soil erosion and increase siltation of river channel, but it can be curtailed through planned urbanization. The urbanization of Skudai watershed is analysed from historical and future perspective. A GIS-based model (Hydrological Simulation Programme-FORTRAN-HSPF is used to modelled sediment flow using basin-wide simulation, and the output result is utilized in evaluating sediment yield reduction due to increased urbanization by swapping multiple temporal land-use of decadent time-steps. The analysis indicates that sediment yield reduces with increase urban built-up and decrease forest and agricultural land. An estimated 12 400 tons of sediment will be reduced for every 27% increase in built-up areas under high rainfall condition and 1 490 tons at low rainfall. The sensitivity analysis of land-use classes shows that built-up, forest and barren are more sensitive to sediment yield reduction compared to wetland and agricultural land at both high and low rainfall. The result of the study suggests that increased urbanization reduced sediment yield in proportion to the rainfall condition and can be used as an alternative approach for soil conservation at watershed scale independent of climate condition.

  18. Determination of priority areas for the re-establishment of forest cover, based on the use of geotechnologies

    Directory of Open Access Journals (Sweden)

    Nelson Wellausen Dias

    2012-12-01

    Full Text Available The determination of priority areas for the re-establishment of forest cover in watersheds is directly associated to the probability of effective success of restoration processes. However, considering the complexity of the analysis and the large amount of spatial data necessary to accomplish that purpose, state of the art technological tools capable of processing multi-criteria analysis to support decision making are necessary. Thus, the current work developed for an area of 476 km² corresponding to the Una river watershed in the municipal district of Taubaté, SP, used a multi-criteria analysis based on the continuous classification and on Analytical Hierarchy Process (AHP paired comparisons techniques, available in the complete GIS package named SPRING (Georeferenced Information Processing System for generating a map of priority areas for the re-establishment of forest cover in that watershed. Results revealed a large area (26.6% of the entire watershed falling in the “Extreme Priority” class for forest cover re-establishment, what indicates the urgent need of environmental recovery of this basin considering that it is used for Taubaté city water supply. Results from this research support the decision making for resource optimization applied to priority areas in an operational way.

  19. Characterization and evaluation of controls on post-fire streamflow response across western US watersheds

    Science.gov (United States)

    Saxe, Samuel; Hogue, Terri S.; Hay, Lauren

    2018-02-01

    strongly influence response. Spearman correlation identified NDVI, aridity index, percent of a watershed's precipitation that falls as rain, and slope as being positively correlated with post-fire streamflow response. This metric also suggested a negative correlation between response and the soil erodibility factor, watershed area, and percent low burn severity. Regression models identified only moderate burn severity and watershed area as being consistently positively/negatively correlated, respectively, with response. The random forest model identified only slope and percent area burned as significant watershed parameters controlling response. Results will help inform post-fire runoff management decisions by helping to identify expected changes to flow regimes, as well as facilitate parameterization for model application in burned watersheds.

  20. Ecological recovery of affected areas by a forest fire in the Tintales watershed (Boyacá, Colombia

    Directory of Open Access Journals (Sweden)

    Fernando Fernández-Méndez

    2016-07-01

    Full Text Available The tintales watershed, located in the Santuario de Flora y Fauna (SFF of Iguaque, Boyaca, was affected by a wildfire. In that area, the natural regeneration was evaluated in 29 permanent plots. Two phyto-physiognomies, a rocky outcrop and oak were evaluated to compare their richness, diversity and dominance, with rocky outcrop yielding a greater richness and diversity. The Asteraceae family was the one that obtained greater representation, with a dominance of species such as Hypoxis decumbens, Pterídium aquilinum and Andropogon bicornis. The diversity in the whole sampling was low and uniform due to the repeated incidence of forest fires that have caused changes in the structure and composition of vegetation. The vegetation found did not differ substantially from other studies reported for this life zone and the region, where the dynamics of land use are similar, with high deforestation and fires. The vegetation established after the fire is dominated by colonizing and pioneering species. In the two phyto physiognomies studied after a year of the fire, two plant communities with statistically significant differences in wealth and homogeneity could be stablished. To start the restoration process, it is recommended to use as one of the inputs, the taxonomic differences found between oak  and rocky outcrop.

  1. Dry deposition of sulfur: a 23-year record for the Hubbard Brook Forest ecosystem

    Energy Technology Data Exchange (ETDEWEB)

    Likens, G E; Eaton, J S [Inst. of Ecosystem Studies, The New York Botanical Garden, NY (US); Bormann, F H [School of Forestry and Environmental Studies Yale Univ., New Haven, CT (US); Hedin, L O [Dept. of Biology, Yale Univ., New Haven, CT (US); Driscoll, C T [Dept. of Civil and Environmental Engineering, Syracuse, NY (US)

    1990-01-01

    Dry deposition of S was estimated for watershed-ecosystems of the Hubbard Brook Experimental Forest from 1964-65 through 1986-87. Two approaches, a regression analysis of bulk precipitation inputs and stream outputs and a mass-balance method, gave similar average values for Watershed 6 430 and 410 eq SO{sub 4}{sup =}/ha-yr, respectively, for this 23-year period. Dry deposition contributed about 37% of total S deposition, varying from 12% in 1964-65 to 61% in 1983-84. Long-term data from 'replicated' watershed-ecosystems showed that temporal variability in estimates of dry deposition was considerably greater than spatial (between watersheds) variability.

  2. Biogeochemistry of a treeline watershed, northwestern Alaska.

    Science.gov (United States)

    Stottlemyer, R

    2001-01-01

    Since 1950, mean annual temperatures in northwestern Alaska have increased. Change in forest floor and soil temperature or moisture could alter N mineralization rates, production of dissolved organic carbon (DOC) and organic nitrogen (DON), and their export to the aquatic ecosystem. In 1990, we began study of nutrient cycles in the 800-ha Asik watershed, located at treeline in the Noatak National Preserve, northwestern Alaska. This paper summarizes relationships between topographic aspect, soil temperature and moisture, inorganic and organic N pools, C pools, CO2 efflux, growing season net N mineralization rates, and stream water chemistry. Forest floor (O2) C/N ratios, C pools, temperature, and moisture were greater on south aspects. More rapid melt of the soil active layer (zone of annual freeze-thaw) and permafrost accounted for the higher moisture. The O2 C and N content were correlated with moisture, inorganic N pools, CO2 efflux, and inversely with temperature. Inorganic N pools were correlated with temperature and CO2 efflux. Net N mineralization rates were positive in early summer, and correlated with O2 moisture, temperature, and C and N pools. Net nitrification rates were inversely correlated with moisture, total C and N. The CO2 efflux increased with temperature and moisture, and was greater on south aspects. Stream ion concentrations declined and DOC increased with discharge. Stream inorganic nitrogen (DIN) output exceeded input by 70%. Alpine stream water nitrate (NO3-) and DOC concentrations indicated substantial contributions to the watershed DIN and DOC budgets.

  3. Precipitation Change and Soil Leaching: Field Results and Simulations from Walker Branch Watershed, Tennessee

    Science.gov (United States)

    D.W. Johnson; P.J. Hanson; D.E. Todd; R.B. Susfalk; Carl C. Trettin

    1998-01-01

    Abstract. To investigate the potential effects of changing precipitation on a deciduous forest ecosystem, an experiment was established on Walker Branch Watershed, Tennessee that modified the amount of throughfall at 4 -33 %. ambient (no change), and +33 % using a system of rain gutters and sprinklers. We hypothesized that the drier treatments would...

  4. Green Infrastructure and Watershed-Scale Hydrology in a Mixed Land Cover System

    Science.gov (United States)

    Hoghooghi, N.; Golden, H. E.; Bledsoe, B. P.

    2017-12-01

    Urbanization results in replacement of pervious areas (e.g., vegetation, topsoil) with impervious surfaces such as roads, roofs, and parking lots, which cause reductions in interception, evapotranspiration, and infiltration, and increases in surface runoff (overland flow) and pollutant loads and concentrations. Research on the effectiveness of different Green Infrastructure (GI), or Low Impact Development (LID), practices to reduce these negative impacts on stream flow and water quality has been mostly focused at the local scale (e.g., plots, small catchments). However, limited research has considered the broader-scale effects of LID, such as how LID practices influence water quantity, nutrient removal, and aquatic ecosystems at watershed scales, particularly in mixed land cover and land use systems. We use the Visualizing Ecosystem Land Management Assessments (VELMA) model to evaluate the effects of different LID practices on daily and long-term watershed-scale hydrology, including infiltration surface runoff. We focus on Shayler Crossing (SHC) watershed, a mixed land cover (61% urban, 24% agriculture, 15% forest) subwatershed of the East Fork Little Miami River watershed, Ohio, United States, with a drainage area of 0.94 km2. The model was calibrated to daily stream flow at the outlet of SHC watershed from 2009 to 2010 and was applied to evaluate diverse distributions (at 25% to 100% implementation levels) and types (e.g., pervious pavement and rain gardens) of LID across the watershed. Results show reduced surface water runoff and higher rates of infiltration concomitant with increasing LID implementation levels; however, this response varies between different LID practices. The highest magnitude response in streamflow at the watershed outlet is evident when a combination of LID practices is applied. The combined scenarios elucidate that the diverse watershed-scale hydrological responses of LID practices depend primarily on the type and extent of the implemented

  5. Land Use and Climate Alter Carbon Dynamics in Watersheds of Chesapeake Bay

    Science.gov (United States)

    Kaushal, S.; Duan, S.; Grese, M.; Pennino, M. J.; Belt, K. T.; Findlay, S.; Groffman, P. M.; Mayer, P. M.; Murthy, S.; Blomquist, J.

    2011-12-01

    There have been long-term changes in the quantity of organic carbon in streams and rivers globally. Shifts in the quality of organic carbon due to environmental changes may also impact downstream ecosystem metabolism and fate and transport of contaminants. We investigated long-term impacts of land use and hydrologic variability on organic carbon transport in watersheds of the Baltimore Long-Term Ecological Research (LTER) site and large rivers of the Chesapeake Bay. In small and medium-sized watersheds of the Baltimore LTER site, urban land use increased organic carbon concentrations in streams several-fold compared to forest and agricultural watersheds. Enzymatic activities of stream microbes were significantly altered across watershed land use during a record wet year. During the wet year, short-term bioassays showed that bioavailable dissolved organic carbon varied seasonally, but comprised a substantial proportion of the dissolved organic carbon pool. Similarly, measurements of biochemical oxygen demand across hydrologic variability suggest that reactive organic carbon export from small and medium-sized urban watersheds during storms can be substantial. At a larger regional scale, major tributaries such as the Potomac, Susquehanna, Patuxent, and Choptank rivers also showed similar variability as smaller watersheds in quantity and quality of organic carbon based on land use and climate. There were distinct isotopic values of d13C of particulate organic matter and fluorescence excitation emission matrices for rivers influenced by different land uses. Stable isotopic values of d13C of particulate organic matter and fluorescence excitation emission matrices showed marked seasonal changes in organic matter quality during spring floods in the Potomac River at Washington D.C. Across watershed size, there appeared to be differences in seasonal cycles of organic carbon quality and this may have been based on the degree of hydrologic connectivity between watersheds and

  6. Characterizing governance and benefits of payments for watershed services in Europe

    OpenAIRE

    Leonardi, Alessandro

    2015-01-01

    Globally, Payments for Watershed Services (PWS) make-up the largest ecosystem service market (Bennett et al., 2014b). Driven by the negative impacts of climate change and economic development for water quantity and quality provision, hydrological services are assuming a leading priority among forest and agriculture-based ecosystems. Indeed, afforestation and sustainable agriculture tend to be among the most rewarded management practices under contracts aiming to achieve additionality in upstr...

  7. Characterization of Solang valley watershed in western Himalaya for bio-resource conservation using remote sensing techniques.

    Science.gov (United States)

    Kumar, Amit; Chawla, Amit; Rajkumar, S

    2011-08-01

    The development activities in mountainous region though provide comfort to the human being and enhance the socioeconomic status of the people but create pressure on the bio-resources. In this paper, the current status of land use/landcover and the vegetation communities of the Solang valley watershed in Himachal Pradesh of Indian western Himalaya has been mapped and presented using remote sensing. This watershed area was dominated by alpine and sub-alpine pastures (30.34%) followed by scree slopes (22.34%) and forests (21.06%). Many tree, shrub, and herb species identified in the study area are among the prioritized species for conservation in the Indian Himalayan Region. Thus, scientific interventions and preparation of action plans based on ecological survey are required for conservation of the Solang valley watershed.

  8. Geochemical investigations and interim recommendations for priority abandoned mine sites on U.S.D.A. Forest Service lands, Mineral Creek watershed, San Juan County, Colorado

    Science.gov (United States)

    Nash, J.T.

    1999-01-01

    Field observations, sampling of mine dumps and mine drainage waters, and laboratory studies of dump materials have been made at mining areas deemed to be on public lands administered by the USDA Forest Service in the Mineral Creek watershed. Results of chemical analyses of dump materials, leachates of those materials, and of surface waters draining mines or dumps provide indications of where acid is generated or consumed, and what metals are mobilized below mines or dumps. Information on 25 sites is reviewed and reclamation priorities are ranked into four classes (high, medium, low priority, or no work required). The western side of the upper Animas watershed (the Mineral Creek watershed) has a history of mining and prospecting for about 130 years. The intensity of miningrelated disturbance is higher than in most parts of the San Juan Mountains region, but actually is much less than the eastern half of the watershed (US BLM lands) and none of the mines moved millions of tons of rock and ore as in some of the eastern mines. The majority of the roughly one thousand mining sites on the USFS lands are very small (less than 100 tons or 70 cubic yards of dump material), are more than 2 miles from a major stream, or are so inaccessible as to prohibit reclamation. Twenty five sites have been considered by others to have significant size and potential for significant environmental degradation. These most significant mining areas were evaluated by multiple criteria, including tendency to generate acid or liberate toxic metals, observed acidic pH or dead vegetation (?kill zones?) below dumps or adits, potential mobility of metals, and likelihood of transport into streams of the watershed. In the author?s opinion, no single measurable parameter, such as metal concentration, is reliable for ranking significance or feasibility of reclamation. Rather, subjective estimates are required to evaluate combinations of, or interactions among, several parameters. The most subjective

  9. Solar radiation as a forest management tool: a primer of principles and application

    Science.gov (United States)

    Howard G. Halverson; James L. Smith

    1979-01-01

    Forests are products of solar radiation use. The sun also drives the hydrologic cycle on forested watersheds. Some basic concepts of climatology and solar radiation are summarized in including earth-sun relations, polar tilt, solar energy, terrestrial energy, energy balance, and local energy. An example shows how these principles can be applied in resource management....

  10. Decreased atmospheric sulfur deposition across the southeastern U.S.: When will watersheds release stored sulfate?

    Science.gov (United States)

    Rice, Karen C.; Scanlon, Todd M.; Lynch, Jason A.; Cosby, Bernard J.

    2014-01-01

    Emissions of sulfur dioxide (SO2) to the atmosphere lead to atmospheric deposition of sulfate (SO42-), which is the dominant strong acid anion causing acidification of surface waters and soils in the eastern United States (U.S.). Since passage of the Clean Air Act and its Amendments, atmospheric deposition of SO2 in this region has declined by over 80%, but few corresponding decreases in stream-water SO42- concentrations have been observed in unglaciated watersheds. We calculated SO42- mass balances for 27 forested, unglaciated watersheds from Pennsylvania to Georgia, by using total atmospheric deposition (wet plus dry) as input. Many of these watersheds still retain SO42-, unlike their counterparts in the northeastern U.S. and southern Canada. Our analysis showed that many of these watersheds should convert from retaining to releasing SO42- over the next two decades. The specific years when the watersheds crossover from retaining to releasing SO42- correspond to a general geographical pattern of later net watershed release from north to south. The single most important variable that explained the crossover year was the runoff ratio, defined as the ratio of annual mean stream discharge to precipitation. Percent clay content and mean soil depth were secondary factors in predicting crossover year. The conversion of watersheds from net SO42- retention to release anticipates more widespread reductions in stream-water SO42- concentrations in this region.

  11. Effect of forest on sediment yield in North China

    Directory of Open Access Journals (Sweden)

    Yu Xinxiao Prof.

    2013-06-01

    Full Text Available Forest-sediment relationship is a hot and important issue in Ecohydrology studies. China has implemented many large-scale reforestation programmes in the last decades to address the growing soil erosion and desertification. In this study, we made statistical and graphic analyses on the long-term hydrological data of the 39 watersheds in the rocky mountain area of the North China, and then we were able to analyze the effect of forest on sediment yield. Our results show that the effect is weak in the lees-precipitation regions (when MAP 500 mm, the impact of forest on reducing sediment yield is different with the varied forest coverage (f, the relationship between the sediment yield and forest coverage show a quadratic polynomial.

  12. Soil properties associated with net nitrification following watershed conversion with Appalachian hardwoods to Norway spruce

    Science.gov (United States)

    Charlene N. Kelly; Stephen H. Schoenholtz; Mary Beth Adams

    2011-01-01

    Nitrate (NO3-N) in soil solution and streamwater can be an important vector of nitrogen (N) loss from forested watersheds, and nitrification is associated with negative consequences of soil acidification and eutrophication of aquatic ecosystems. The purpose of this study was to identify vegetation-mediated soil properties that may control...

  13. Response of aquatic macrophytes to human land use perturbations in the watersheds of Wisconsin lakes, U.S.A.

    Science.gov (United States)

    Sass, Laura L.; Bozek, Michael A.; Hauxwell, Jennifer A.; Wagner, Kelly; Knight, Susan

    2010-01-01

    Aquatic macrophyte communities were assessed in 53 lakes in Wisconsin, U.S.A. along environmental and land use development gradients to determine effects human land use perturbations have on aquatic macrophytes at the watershed and riparian development scales. Species richness and relative frequency were surveyed in lakes from two ecoregions: the Northern Lakes and Forests Ecoregion and the Southeastern Wisconsin Till Plain Ecoregion. Lakes were selected along a gradient of watershed development ranging from undeveloped (i.e., forested), to agricultural to urban development. Land uses occurring in the watershed and in perimeters of different width (0–100, 0–200, 0–500, and 0–1000 m from shore, in the watershed) were used to assess effects on macrophyte communities. Snorkel and SCUBA were used to survey aquatic macrophyte species in 18 quadrats of 0.25 m2 along 14 transects placed perpendicular to shore in each lake. Effects of watershed development (e.g., agriculture and/or urban) were tested at whole-lake (entire littoral zone) and near-shore (within 7 m of shore) scales using canonical correspondence analysis (CCA) and linear regression. Overall, species richness was negatively related to watershed development, while frequencies of individual species and groups differed in level of response to different land use perturbations. Effects of land use in the perimeters on macrophytes, with a few exceptions, did not provide higher correlations compared to land use at the watershed scale. In lakes with higher total watershed development levels, introduced species, particularly Myriophyllumspicatum, increased in abundance and native species, especially potamids, isoetids, and floating-leaved plants, declined in abundance. Correlations within the northern and southeastern ecoregions separately were not significant. Multivariate analyses suggested species composition is driven by environmental responses as well as human development pressures. Both water

  14. Coffee agroforestry for sustainability of Upper Sekampung Watershed management

    Science.gov (United States)

    Fitriani; Arifin, Bustanul; Zakaria, Wan Abbas; Hanung Ismono, R.

    2018-03-01

    The main objective of watershed management is to ensure the optimal hydrological and natural resource use for ecological, social and economic importance. One important adaptive management step in dealing with the risk of damage to forest ecosystems is the practice of agroforestry coffee. This study aimed to (1) assess the farmer's response to ecological service responsibility and (2) analyze the Sekampung watersheds management by providing environmental services. The research location was Air Naningan sub-district, Tanggamus, Lampung Province, Indonesia. The research was conducted from July until November 2016. Stratification random sampling based on the pattern of ownership of land rights is used to determine the respondents. Data were analyzed using descriptive statistics and logistic regression analysis. Based on the analysis, it was concluded that coffee farmers' participation in the practice of coffee agroforestry in the form of 38% shade plants and multiple cropping (62%). The logistic regression analysis indicated that the variables of experience and status of land ownership, and incentive-size plans were able to explain variations in the willingness of coffee growers to follow the scheme of providing environmental services. The existence of farmer with partnership and CBFM scheme on different land tenure on upper Sekampung has a strategic position to minimize the deforestation and recovery watersheds destruction.

  15. Extra-Property Legal Reserve in the Cerrado Biome: A preliminary Analysis within the Watershed Context

    Directory of Open Access Journals (Sweden)

    Fábio Carneiro Lobo

    2006-08-01

    Full Text Available This paper presents a normalized remaining vegetation index (NRVI based on land use data, which is evaluated according to three distinct minimum watershed sizes (10,000, 50,000 and 200,000 ha , whose limits were derived via SRTM data (Shuttle Radar Topography Mission. The NRVI varies from -1 (i. e. entirely converted watersheds to 1 (no conversion at all, and allows the association of land use data to numerical variables, such as social development indices. High NRVI values were found in the Northeastern watersheds of Goias State , while negative NRVI values predominated in the Southeastern and Southern portions of the study area. In compliance to the Brazilian Forest Code (i. e. permanent preservation areas and legal reserve, we estimated an NRVI value of -0.382, which is found in only 50,13% of the 10,000 ha watersheds. Although preliminary, our results suggest that NRVI can effectively serve the purposes of a transferable development rights approach (TDR regarding legal reserves in the State of Goias and Federal District.

  16. RESPONSE OF LANDUSE CHANGE ON HYDROLOGICAL CHARACTERISTICS OF WAY BETUNG WATERSHED - LAMPUNG

    Directory of Open Access Journals (Sweden)

    Zaenal Mubarok

    2015-05-01

    Full Text Available Change in landuse caused by a population increase from 114,973 people in 2007 to 134,792 people in 2012 (14.70% increased has influenced the hydrological characteristics of Way Betung watershed. The Soil and Water Assesment Tools (SWAT hydrological model could predict the hydrological characteristics influenced by the change in landuse. The aims of this study were: 1 to assess the impact of landuse change on hydrological characteristics; and, 2 to recommend the best landuse of Way Betung Watershed.The SWAT model was applied to simulate the change of landuse in Way Betung watershed. The effects of landuse change on the hydrological characteristics of Way Betung Watershed in 2001, 2006, and 2010 showed  the water yield of 874.66, 1047.70, and 774.04 mm respectively. The coefficient of surface runoff (C for those three years were 0.16, 0.31, and 0.23, whereas the coeficient of river regime were 30.65, 66.25, and 53.57 respectively. The application of agrotechnology on agricultural land and in line with the functions of forest area (scenario 4 gave the best response towards hydrological characteristics in the form of 709.69 mm of water yield with C being 0.14, whereas the coeficient of river regime value was 3.66. 

  17. Retrospective Analysis of Low Flows at Headwater Watersheds in Wyoming

    Science.gov (United States)

    Voutchkova, D. D.; Miller, S. N.

    2016-12-01

    Understanding summer low-flow variability and change in the mountainous West has important implications for water allocations downstream and for maintaining water availability for drinking water supply, reservoir storage, industrial, agricultural, and ecological needs. Wildfires and insect infestations are classical disturbance hydrology topics. It is unclear, however, what are their effects on streamflow and in particular low-flows, when vegetation disturbances are overlapping in time and combined with highly variable and potentially changing local climate. The purpose of this study, therefore, is to quantify changes in low-flows resulting from disturbance in headwater streams. Here we present a retrospective analysis based on: (1) 49-75 complete water years (wy) of daily streamflow data (USGS) for 14 high-elevation headwater watersheds with varying areas (60-1730 km2, 86-100% of watershed area >2000masl) and evergreen forest cover (15-82%), (2) 25-36 complete wy of daily snow-water equivalent accumulation (SWE) and precipitation data from Wyoming SNOTEL stations, (3) burned area boundaries for 20wy (MTBS project), (4) aerial surveys by R1, R2, R4 Forest Service Regions for 18wy (data on tree mortality). We quantify the change in various low-flow characteristics (e.g. post-snowmelt baseflow, Q90 and Q95, 3-,7-, 30- and 90-day annual minima etc.) while accounting for local inter- and multi-annual climate variability by using SWE accumulation data, as it integrates both temperature and precipitation changes. Our approach differs from typical before-after field-based investigation for paired watersheds, as it provides a synthesis over large temporal and spatial scales, resulting in spectrum of possible hydrologic responses due to varying disturbance severity. Quantifying the changes in low-flows and low-flow variability will improve our understanding and will facilitate water management and planning at local state-wide level.

  18. Macroinvertebrate and algal community sample collection methods and data collected at selected sites in the Eagle River watershed, Colorado, 2000-07

    Science.gov (United States)

    Zuellig, Robert E.; Bruce, James F.

    2010-01-01

    State and local agencies are concerned about the effects of increasing urban development and human population growth on water quality and the biological condition of regional streams in the Eagle River watershed. In response to these needs, the U.S. Geological Survey initiated a study in cooperation with the Colorado River Water Conservation District, Eagle County, Eagle River Water and Sanitation District, Upper Eagle Regional Water Authority, Colorado Department of Transportation, City of Aurora, Town of Eagle, Town of Gypsum, Town of Minturn, Town of Vail, Vail Resorts, Colorado Springs Utilities, Denver Water, and the U.S. Department of Agriculture Forest Service. As part of this study, previously collected macroinvertebrate and algal data from the Eagle River watershed were compiled. This report includes macroinvertebrate data collected by the U.S. Geological Survey and(or) the U.S. Department of Agriculture Forest Service from 73 sites from 2000 to 2007 and algal data collected from up to 26 sites between 2000 and 2001 in the Eagle River watershed. Additionally, a brief description of the sample collection methods and data processing procedures are presented.

  19. Regional Comparison of Nitrogen Export to Japanese Forest Streams

    Directory of Open Access Journals (Sweden)

    Hideaki Shibata

    2001-01-01

    Full Text Available Nitrogen (N emissions in Asian countries are predicted to increase over the next several decades. An understanding of the mechanisms that control temporal and spatial fluctuation of N export to forest streams is important not only to quantify critical loads of N, N saturation status, and soil acidification N dynamics and budgets in Japanese forested watersheds is not clear due to the lack of regional comparative studies on stream N chemistry. To address the lack of comparative studies, we measured inorganic N (nitrate and ammonium concentrations from June 2000 to May 2001 in streams in 18 experimental forests located throughout the Japanese archipelago and belonging to the Japanese Union of University Forests. N concentrations in stream water during base flow and high flow periods were monitored, and N mineralization potential in soil was measured using batch incubation experiments. Higher nitrate concentrations in stream water were present in central Japan, an area that receives high rates of atmospheric N deposition. In northern Japan, snowmelt resulted in increased nitrate concentrations in stream water. The potential net N mineralization rate was higher in surface soil than in subsurface soil, and the high potential for N mineralization in the surface soil partly contributed to the increase in nitrate concentration in stream water during a storm event. Regional differences in the atmospheric N deposition and seasonality of precipitation and high discharge are principal controls on the concentrations and variations of nitrates in stream water in forested watersheds of Japan.

  20. Multi-Elements in Waters and Sediments of Shallow Lakes: Relationships with Water, Sediment, and Watershed Characteristics.

    Science.gov (United States)

    Kissoon, La Toya T; Jacob, Donna L; Hanson, Mark A; Herwig, Brian R; Bowe, Shane E; Otte, Marinus L

    2015-06-01

    We measured concentrations of multiple elements, including rare earth elements, in waters and sediments of 38 shallow lakes of varying turbidity and macrophyte cover in the Prairie Parkland (PP) and Laurentian Mixed Forest (LMF) provinces of Minnesota. PP shallow lakes had higher element concentrations in waters and sediments compared to LMF sites. Redundancy analysis indicated that a combination of site- and watershed-scale features explained a large proportion of among-lake variability in element concentrations in lake water and sediments. Percent woodland cover in watersheds, turbidity, open water area, and macrophyte cover collectively explained 65.2 % of variation in element concentrations in lake waters. Sediment fraction smaller than 63 µm, percent woodland in watersheds, open water area, and sediment organic matter collectively explained 64.2 % of variation in element concentrations in lake sediments. In contrast to earlier work on shallow lakes, our results showed the extent to which multiple elements in shallow lake waters and sediments were influenced by a combination of variables including sediment characteristics, lake morphology, and percent land cover in watersheds. These results are informative because they help illustrate the extent of functional connectivity between shallow lakes and adjacent lands within these lake watersheds.

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

    Science.gov (United States)

    F. N. Scatena

    1990-01-01

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

  2. Extending WEPP technology to predict fine sediment and phosphorus delivery from forested hillslopes

    Science.gov (United States)

    William Elliot; Erin Brooks; Drea Em Traeumer; Mariana Dobre

    2015-01-01

    In many watersheds, including the Great Lakes and Lake Tahoe Basins, two basins where the land cover is dominated by forests, the pollutants of concern are fine sediments and phosphorus. Forest runoff is generally low in nitrogen, and coarse sediment does not adversely impact the quality of lake waters. Predictive tools are needed to estimate not simply sediment, but...

  3. Characterization and evaluation of controls on post-fire streamflow response across western US watersheds

    Directory of Open Access Journals (Sweden)

    S. Saxe

    2018-02-01

    other watershed factors strongly influence response. Spearman correlation identified NDVI, aridity index, percent of a watershed's precipitation that falls as rain, and slope as being positively correlated with post-fire streamflow response. This metric also suggested a negative correlation between response and the soil erodibility factor, watershed area, and percent low burn severity. Regression models identified only moderate burn severity and watershed area as being consistently positively/negatively correlated, respectively, with response. The random forest model identified only slope and percent area burned as significant watershed parameters controlling response. Results will help inform post-fire runoff management decisions by helping to identify expected changes to flow regimes, as well as facilitate parameterization for model application in burned watersheds.

  4. Understanding human impacts to tropical coastal ecosystems through integrated hillslope erosion measurements, optical coastal waters characterization, watershed modeling, marine ecosystem assessments, and natural resource valuations in two constrasting watersheds in Puerto Rico.

    Science.gov (United States)

    Ortiz-Zayas, J.; Melendez, J.; Barreto, M.; Santiago, L.; Torres-Perez, J. L.; Ramos-Scharron, C. E.; Figueroa, Y.; Setegn, S. G.; Guild, L. S.; Armstrong, R.

    2017-12-01

    Coastal ecosystems are an asset to many tropical island economies. In Puerto Rico, however, many invaluable coastal ecosystems are at risk due to multiple social and natural environmental stressors. To quantify the role of anthropogenic versus natural stressors, an integrated multidisciplinary approach was applied in two contrasting watersheds in Puerto Rico. The Rio Loco (RL) watershed in Southeastern Puerto Rico is hydrologically modified with interbasin water transfers, hydroelectric generation, and with water extraction for irrigation and water supply. Intensive agricultural production dominates both the lower and upper portions of the basin. In contrast, the Rio Grande de Manatí (RGM) shows a natural flow regime with minor flow regulation and limited agriculture. The Surface Water Assessment Tool (SWAT) was applied to each watershed to assess the effects of land use changes on water and sediment fluxes to coastal areas. From 1977 to 2016, forest areas increased in both watersheds due to the abandonment of farms in the mountains. However, in upper and lower RL, agricultural lands have remained active. Coffee plantations in the upper watershed contribute with high sediment loads, particularly in unpaved service roads. We hypothesize that water fluxes will be higher in the larger RGM than in RL. However, suspended sediment fluxes will be higher in the agriculturally active RL basin. A willingness-to-pay approach was applied to assess how residents from each watershed value water and coastal ecosystems revealing a general higher natural resources valuation in the RGM than in RL. Coastal ecosystems at each site revealed structural differences in benthic coral communities due to local currents influenced largely by coastal morphology. The optical properties of coastal waters are also being determined and linked to fluvial sediment fluxes. Stakeholder meetings are being held in each watershed to promote transfer of scientific insights into a sustainable coastal and

  5. Role of storms and forest practices in sedimentation of an Oregon Coast Range lake

    Science.gov (United States)

    Richardson, K.; Hatten, J. A.; Wheatcroft, R. A.; Guerrero, F. J.

    2014-12-01

    The design of better management practices in forested watersheds to face climate change and the associated increase in the frequency of extreme events requires a better understanding of watershed responses to extreme events in the past and also under management regimes. One of the most sensitive watershed processes affected is sediment yield. Lake sediments record events which occur in a watershed and provide an opportunity to examine the interaction of storms and forest management practices in the layers of the stratigraphy. We hypothesize that timber harvesting and road building since the 1900s has resulted in increases in sedimentation; however, the passage of the Oregon Forest Practices Act (OFPA) in 1972 has led to a decrease in sedimentation. Sediment cores were taken at Loon Lake in the Oregon Coast Range. The 32-m deep lake captures sediment from a catchment highly impacted by recent land use and episodic Pacific storms. We can use sedimentological tools to measure changes in sediment production as motivated by extreme floods before settlement, during a major timber harvesting period, and after installation of forestry Best Management Practices. Quantification of changes in particle size and elemental composition (C, N, C/N) throughout the cores can elucidate changes in watershed response to extreme events, as can changes in layer thickness. Age control in the cores is being established by Cesium-137 and radiocarbon dating. Given the instrumental meteorological data and decadal climate reconstructions, we will disentangle climate driven signals from changes in land use practices. The sediment shows distinct laminations and varying thickness of layers throughout the cores. Background deposition is composed of thin layers (events to determine if the OFPA is having an effect on reducing sedimentation rates as a result of extreme magnitude storm events.

  6. PRIORITY AREAS FOR FOREST CONSERVATION, AIMING AT THE MAINTENANCE OF WATER RESOURCES, THROUGH THE MULTICRITERIA EVALUATION1

    Directory of Open Access Journals (Sweden)

    Victor A M Silva

    2017-11-01

    Full Text Available Abstract Replacing the original land cover by other land uses, especially when it is associated with inadequate management practices, can cause changes in runoff and rainwater infiltration. This can result in above normal levels of soil erosion and sediment-carrying to the rivers and streams. The original land cover conservation in the watersheds is, therefore, essential for the maintenance of its water resources. In this context, the main objective of this study was to prioritize areas for forest conservation in two watersheds, aiming at maintaining the water availability, in terms of quantity and quality, for the public supply. The watersheds were selected considering their regional importance and because they are similar in terms of land use / land cover. The study was developed in the Multicriteria Evaluation (MCE context, which permits the integration of different landscape characteristics (i.e. factors, in order to obtain a solution for the decision-making process. The following criteria were selected by considering the expert's opinions: slope, flow accumulation, aspect, and land use / land cover. Their relative importance (i.e. factor weight was defined through the Pairwise Comparison Method. The criteria maps units were normalized by a common scale and then aggregated through an MCE method named Weighted Linear Combination (WLC. Pearson correlation was used to evaluate the criteria contribution on the final map. The watershed 1 was classified in approximately 14% of its area as very high priority; 27% as high; 19% as medium; 21% as low; and 18% as very low. The watershed 2 obtained, respectively, 17%; 29%; 17%; 21%; e 17%. We conclude that the WLC method supports the definition of priority areas for forest conservation in the watersheds, in order to have an appropriate design of actions for forest conservation.

  7. Coastal Fog Sustains Summer Baseflow in Northern Californian Watershed

    Science.gov (United States)

    Chung, M.; Dufour, A.; Leonardson, R.; Thompson, S. E.; Dawson, T. E.

    2015-12-01

    The Mediterranean climate of Northern California imposes significant water stress on ecosystems and water resources during the dry summer months. During summer, frequently the only water inputs occur as occult precipitation, in the form of fog and dew. In this study, we characterized the role of coastal fog, a dominant feature of Northern Californian coastal ecosystems and a widespread phenomenon associated with deep marine upwelling in west coast, arid, and Mediterranean climates worldwide. We monitored fog occurrence and intensity, throughfall following canopy interception of fog, soil moisture, streamflow, and meteorological variables, and made visual observations of the spatial extent of fog using time-lapse imagery in Upper Pilarcitos Creek Watershed (managed by San Francisco Public Utilities Commission as part of the San Francisco area water supply). We adopted a stratified sampling design that captured the watershed's elevation gradient, forest-edge versus interior locations, and different vegetation cover. The point-scale observations of throughfall inputs and transpiration suppression, estimated from the Penman equation, were upscaled using such watershed features and the observed fog "footprint" identified from the time-lapse images. When throughfall input and fog-induced transpiration suppression were incorporated into the operational watershed model, they improved estimates of summer baseflow, which remained persistently higher than could be explained without the fog effects. Fog, although providing relatively small volumetric inputs to the water balance, appears to offer significant relief of water stress throughout the terrestrial and aquatic components of the coastal Californian ecosystem and thus should be accounted for when assessing water stress availability in dry ecosystems.

  8. Substrate availability drives spatial patterns in richness of ammonia-oxidizing bacteria and archaea in temperate forest soils

    Science.gov (United States)

    J.S. Norman; J.E. Barrett

    2016-01-01

    We sought to investigate the drivers of richness of ammonia-oxidizing bacteria (AOB) and archaea (AOA) in temperate forest soils. We sampled soils across four experimental watersheds in the Coweeta Hydrologic Laboratory, North Carolina USA. These watersheds are geographically close, but vary in soil chemistry due to differences in land use history. While we...

  9. Prediction of Land Use Change in Long Island Sound Watersheds Using Nighttime Light Data

    Directory of Open Access Journals (Sweden)

    Ruiting Zhai

    2016-12-01

    Full Text Available The Long Island Sound Watersheds (LISW are experiencing significant land use/cover change (LUCC, which affects the environment and ecosystems in the watersheds through water pollution, carbon emissions, and loss of wildlife. LUCC modeling is an important approach to understanding what has happened in the landscape and what may change in the future. Moreover, prospective modeling can provide sustainable and efficient decision support for land planning and environmental management. This paper modeled the LUCCs between 1996, 2001 and 2006 in the LISW in the New England region, which experienced an increase in developed area and a decrease of forest. The low-density development pattern played an important role in the loss of forest and the expansion of urban areas. The key driving forces were distance to developed areas, distance to roads, and social-economic drivers, such as nighttime light intensity and population density. In addition, this paper compared and evaluated two integrated LUCC models—the logistic regression–Markov chain model and the multi-layer perception–Markov chain (MLP–MC model. Both models achieved high accuracy in prediction, but the MLP–MC model performed slightly better. Finally, a land use map for 2026 was predicted by using the MLP–MC model, and it indicates the continued loss of forest and increase of developed area.

  10. Third annual Walker Branch Watershed research symposium. Program and abstracts

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    The methods and concepts of watershed research, originally applied in an experimental or monitoring mode to relatively small catchments, are increasingly being used at larger scales and for specific applied problems. Research at Oak Ridge National Laboratory, the Tennessee Valley Authority, the US Forest Service, and other agencies and institutions participating in this symposium reflects research over a broad range of spatial scales that is being integrated through large-scale experiments along with computer modeling and graphical interfaces. These research projects address the basic atmospheric, geophysical, biogeochemical, and biological processes that regulate the responses of forested ecosystems to natural environmental variation and anthropogenic stresses. Regional and global issues addressed by presentations include emissions of carbon dioxide, methane, and other hydrocarbons; deposition of sulfate, nitrate, and mercury; land-use changes; biological diversity; droughts; and water quality. The reports presented in this symposium illustrate a wide range of methods and approaches and focus more on concepts and techniques than on a specific physical site. Sites and projects that have contributed research results to this symposium include Walker Branch Watershed (DOE), the Coweeta Hydrologic Laboratory and LTER site (USFS and NSF), Great Smoky Mountains National Park (research funded by NPS, TVA, and EPRI), Imnavait Creek, Alaska (DOE), the TVA-Norris Whole-tree Facility (TVA and EPRI), and DOE`s Biomass Program.

  11. Application of the SWAT model to the Xiangjiang river watershed in subtropical central China.

    Science.gov (United States)

    Luo, Qiao; Li, Yong; Wang, Kelin; Wu, Jinshui

    2013-01-01

    The Soil and Water Assessment Tool (SWAT) model was applied to simulate the water balance in the Xiangjiang river watershed for current and planning scenarios of land uses. The model was first calibrated for the period from 1998 to 2002 and then validated for the period from 2003 to 2007 using the observed stream flow data from four monitoring gages within the watershed. The determination coefficient of linear regression of the observed and simulated monthly stream flows (R(2)) and their Nash-Sutcliffe Index (NSI) was used to evaluate model performance. All values of R(2) and NSI were above 0.8 and ranged from 0.82 to 0.92, which indicates that the SWAT model was capable of simulating the stream flow in the Xiangjiang river watershed. The calibrated and validated SWAT model was then applied to study the hydrological response of three land use change scenarios. Runoff was reduced by increasing the areas of forest and grassland while simultaneously decreasing the areas of agricultural and urban land. In the recent and future land use planning for the Xiangjiang river watershed, the hydrological effect should be considered in regional water management and erosion control.

  12. Estimating the erosion and deposition rates in a small watershed by the 137Cs tracing method

    International Nuclear Information System (INIS)

    Li Mian; Li Zhanbin; Yao Wenyi; Liu Puling

    2009-01-01

    Understanding the erosion and deposition rates in a small watershed is important for designing soil and water conservation measures. The objective of this study is to estimate the net soil loss and gain at points with various land use types and landform positions in a small watershed in the Sichuan Hilly Basin of China by the 137 Cs tracing technique. Among various land use types, the order of erosion rate was bare rock > sloping cultivated land > forest land. The paddy field and Caotu (a kind of cultivated land located at the foot of hills) were depositional areas. The erosion rate under different landform was in this order: hillside > saddle > hilltop. The footslope and the valley were depositional areas. The 137 Cs technique was shown to provide an effective means of documenting the spatial distribution of soil erosion and deposition within the small watershed

  13. Estimating the Net Economic Value of National Forest Recreation: An Application of the National Visitor Use Monitoring Database

    Science.gov (United States)

    J.M. Bowker; C.M. Starbuck; D.B.K. English; J.C. Bergstrom; R.S. Rosenburger; D.C. McCollum

    2009-01-01

    The USDA Forest Service (FS) manages 193 million acres of public land in the United States. These public resources include vast quantities of natural resources including timber, wildlife, watersheds, air sheds, and ecosystems. The Forest Service was established in 1905, and the FS has been directed by Congress to manage the National Forests and Grasslands for the...

  14. Quantifying suspended sediment flux in a mixed-land-use urbanizing watershed using a nested-scale study design.

    Science.gov (United States)

    Zeiger, Sean; Hubbart, Jason A

    2016-01-15

    Suspended sediment (SS) remains the most pervasive water quality problem globally and yet, despite progress, SS process understanding remains relatively poor in watersheds with mixed-land-use practices. The main objective of the current work was to investigate relationships between suspended sediment and land use types at multiple spatial scales (n=5) using four years of suspended sediment data collected in a representative urbanized mixed-land-use (forest, agriculture, urban) watershed. Water samples were analyzed for SS using a nested-scale experimental watershed study design (n=836 samples×5 gauging sites). Kruskal-Wallis and Dunn's post-hoc multiple comparison tests were used to test for significant differences (CI=95%, p<0.05) in SS levels between gauging sites. Climate extremes (high precipitation/drought) were observed during the study period. Annual maximum SS concentrations exceeded 2387.6 mg/L. Median SS concentrations decreased by 60% from the agricultural headwaters to the rural/urban interface, and increased by 98% as urban land use increased. Multiple linear regression analysis results showed significant relationships between SS, annual total precipitation (positive correlate), forested land use (negative correlate), agricultural land use (negative correlate), and urban land use (negative correlate). Estimated annual SS yields ranged from 16.1 to 313.0 t km(-2) year(-1) mainly due to differences in annual total precipitation. Results highlight the need for additional studies, and point to the need for improved best management practices designed to reduce anthropogenic SS loading in mixed-land-use watersheds. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Poverty and Environmental Services: Case Study in Way Besai Watershed, Lampung Province, Indonesia

    Directory of Open Access Journals (Sweden)

    S. Suyanto

    2007-12-01

    Full Text Available Local communities in developing countries are often forbidden to earn their livelihood from state-owned forests, but nonetheless local people commonly manage these lands and depend on them to survive. In these places, community participation is the key to successful conservation programs intended to rehabilitate environmental functions and produce environmental services for beneficiaries outside the area. This paper reviews the relationship between poverty and environmental services and briefly discusses the main ways in which approaches that rely on payment for environmental services are thought likely to alleviate poverty. It also discusses the poverty profile and inequality of upland dwellers in the Sumberjaya watershed in Indonesia's Lampung Province, using income, education, and land-holding indicators. Data related to these three indicators were collected from intensive household surveys and interviews and used via Gini decomposition to measure inequality. In addition, analysis of data on stem at breast height and horizontal root diameter of coffee and other noncoffee trees planted on coffee farms showed that index of root shallowness could be used as an estimator of environmental services. This study revealed that state forest land in Lampung Province, Indonesia, not only provides important income for poor farmers but also leads to a more equitable distribution of income and land holdings. These farmers have also successfully rehabilitated degraded land by establishing coffee-based agroforestry. As found in other recent studies, these findings show that coffee-based agroforestry can perform watershed service functions similar to those of natural, undisturbed forests. This supports the argument that poor farmers who provide environmental services through their activities in state-owned forests should be rewarded with land rights as a policy to alleviate poverty.

  16. Geomorphology, disturbance, and the soil and vegetation of two subtropical wet steepland watersheds of Puerto Rico.

    Science.gov (United States)

    Ariel E. Lugo F.N. Scatena

    1995-01-01

    Relationships between landforms, soil nutrients, forest structure, and the relative importance of different disturbances were quantified in two subtropical wet steepland watersheds in Puerto Rico. Ridges had fewer landslides and treefall gaps, more above-ground biomass, older aged stands, and greater species richness than other landscape positions. Ridge soils had...

  17. Evaluating Hydrologic Response of an Agricultural Watershed for Watershed Analysis

    Directory of Open Access Journals (Sweden)

    Manoj Kumar Jha

    2011-06-01

    Full Text Available This paper describes the hydrological assessment of an agricultural watershed in the Midwestern United States through the use of a watershed scale hydrologic model. The Soil and Water Assessment Tool (SWAT model was applied to the Maquoketa River watershed, located in northeast Iowa, draining an agriculture intensive area of about 5,000 km2. The inputs to the model were obtained from the Environmental Protection Agency’s geographic information/database system called Better Assessment Science Integrating Point and Nonpoint Sources (BASINS. Meteorological input, including precipitation and temperature from six weather stations located in and around the watershed, and measured streamflow data at the watershed outlet, were used in the simulation. A sensitivity analysis was performed using an influence coefficient method to evaluate surface runoff and baseflow variations in response to changes in model input hydrologic parameters. The curve number, evaporation compensation factor, and soil available water capacity were found to be the most sensitive parameters among eight selected parameters. Model calibration, facilitated by the sensitivity analysis, was performed for the period 1988 through 1993, and validation was performed for 1982 through 1987. The model was found to explain at least 86% and 69% of the variability in the measured streamflow data for calibration and validation periods, respectively. This initial hydrologic assessment will facilitate future modeling applications using SWAT to the Maquoketa River watershed for various watershed analyses, including watershed assessment for water quality management, such as total maximum daily loads, impacts of land use and climate change, and impacts of alternate management practices.

  18. Statistically extracted fundamental watershed variables for estimating the loads of total nitrogen in small streams

    Science.gov (United States)

    Kronholm, Scott C.; Capel, Paul D.; Terziotti, Silvia

    2016-01-01

    Accurate estimation of total nitrogen loads is essential for evaluating conditions in the aquatic environment. Extrapolation of estimates beyond measured streams will greatly expand our understanding of total nitrogen loading to streams. Recursive partitioning and random forest regression were used to assess 85 geospatial, environmental, and watershed variables across 636 small (monitoring may be beneficial.

  19. Hydrologic Effects of Global Climate Change on a Large Drained Pine Forest

    Science.gov (United States)

    Devendra M. Amatya; Ge Sun; R. W. Skaggs; G. M Chescheir; J. E. Nettles

    2006-01-01

    A simulation study using a watershed scale forest hydrology model (DRAINWAT) was conducted to evaluate potential effects of climate change on the hydrology of a 3,000 ha managed pine forest in coastal North Carolina. The model was first validated with a five-year (1996-2000) data set fro111 the study site and then run with 50-years (1951-00) of historic weather data...

  20. Simulated water budget of a small forested watershed in the continental/maritime hydroclimatic region of the United States

    Science.gov (United States)

    Liang Wei; Timothy E. Link; Andrew T. Hudak; John D. Marshall; Kathleen L. Kavanagh; John T. Abatzoglou; Hang Zhou; Robert E. Pangle; Gerald N. Flerchinger

    2016-01-01

    Annual streamflows have decreased across mountain watersheds in the Pacific Northwest of the United States over the last ~70 years; however, in some watersheds, observed annual flows have increased. Physically based models are useful tools to reveal the combined effects of climate and vegetation on long-term water balances by explicitly simulating the internal...

  1. An annotated bibliography of scientific literature on research and management activities conducted in Manitou Experimental Forest

    Science.gov (United States)

    Ilana Abrahamson

    2012-01-01

    The Manitou Experimental Forest (MEF) is part of the USDA Forest Service Rocky Mountain Research Station. Established in 1936, its early research focused on range and watershed management. Currently, the site is home to several meteorological, ecological and biological research initiatives. Our collaborators include the University of Colorado, Colorado State University...

  2. Watershed evapotranspiration increased due to changes in vegetation composition and structure under a subtropical climate

    Science.gov (United States)

    Ge Sun; Changqing Zuo; Shiyu Liu; Mingliang Liu; Steven G McNulty; James M. Vose

    2008-01-01

    Natural forests in southern China have been severely logged due to high human demand for timber, food, and fuels during the past century, but are recovering in the past decade. The objective of this study was to investigate how vegetation cover changes in composition and structure affected the water budgets of a 9.6-km2 Dakeng watershed located...

  3. Modeled ecohydrological responses to climate change at seven small watersheds in the northeastern United States

    Science.gov (United States)

    Afshin Pourmokhtarian; Charles T. Driscoll; John L. Campbell; Katharine Hayhoe; Anne M. K. Stoner; Mary Beth Adams; Douglas Burns; Ivan Fernandez; Myron J. Mitchell; James B. Shanley

    2016-01-01

    A cross-site analysis was conducted on seven diverse, forested watersheds in the northeastern United States to evaluate hydrological responses (evapotranspiration, soil moisture, seasonal and annual streamflow, and water stress) to projections of future climate. We used output from four atmosphere–ocean general circulation models (AOGCMs; CCSM4, HadGEM2-CC, MIROC5, and...

  4. Dynamics of Ecosystem Services during Forest Transitions in Reventazón, Costa Rica.

    Science.gov (United States)

    Vallet, Améline; Locatelli, Bruno; Levrel, Harold; Brenes Pérez, Christian; Imbach, Pablo; Estrada Carmona, Natalia; Manlay, Raphaël; Oszwald, Johan

    2016-01-01

    The forest transition framework describes the temporal changes of forest areas with economic development. A first phase of forest contraction is followed by a second phase of expansion once a turning point is reached. This framework does not differentiate forest types or ecosystem services, and describes forests regardless of their contribution to human well-being. For several decades, deforestation in many tropical regions has degraded ecosystem services, such as watershed regulation, while increasing provisioning services from agriculture, for example, food. Forest transitions and expansion have been observed in some countries, but their consequences for ecosystem services are often unclear. We analyzed the implications of forest cover change on ecosystem services in Costa Rica, where a forest transition has been suggested. A review of literature and secondary data on forest and ecosystem services in Costa Rica indicated that forest transition might have led to an ecosystem services transition. We modeled and mapped the changes of selected ecosystem services in the upper part of the Reventazón watershed and analyzed how supply changed over time in order to identify possible transitions in ecosystem services. The modeled changes of ecosystem services is similar to the second phase of a forest transition but no turning point was identified, probably because of the limited temporal scope of the analysis. Trends of provisioning and regulating services and their tradeoffs were opposite in different spatial subunits of our study area, which highlights the importance of scale in the analysis of ecosystem services and forest transitions. The ecosystem services transition framework proposed in this study is useful for analyzing the temporal changes of ecosystem services and linking socio-economic drivers to ecosystem services demand at different scales.

  5. Forest operations, extreme flooding events, and considerations for hydrologic modeling in the Appalachians--A review

    Science.gov (United States)

    M.A. Eisenbies; W.M. Aust; J.A. Burger; M.B. Adams

    2007-01-01

    The connection between forests and water resources is well established, but the relationships among controlling factors are only partly understood. Concern over the effects of forestry operations, particularly harvesting, on extreme flooding events is a recurrent issue in forest and watershed management. Due to the complexity of the system, and the cost of installing...

  6. Climate change: detecting climate's imprint on California forests

    Science.gov (United States)

    Anne M. Rosenthal; Constance I. Millar

    2003-01-01

    Hiking the nearly treeless slopes of western Nevada's Wassuk Range, researcher Connie Millar found dead limber pine throughout the watersheds. Where scanty forests were present, the dead wood occurred above treeline. Investigation of these wood remnants, sculpted by the elements over hundreds of years, revealed a cyclical pattern of limber pine colonization and...

  7. Runoff response to climate change and human activities in a typical karst watershed, SW China.

    Science.gov (United States)

    Xu, Yan; Wang, Shijie; Bai, Xiaoyong; Shu, Dongcai; Tian, Yichao

    2018-01-01

    This study aims to reveal the runoff variation characteristics of long time series in a karst region, analyse comprehensively its different driving factors, and estimate quantitatively the contribution rates of climate change and human activities to net runoff variation. Liudong river basin, a typical karst watershed in southwest China, is the study site. Statistical methods, such as linear fitting, the Morlet wavelet analysis, normalized curve and double mass curve, are applied to analyse the runoff of the watershed. Results show that the runoff in the karst watershed during the research period exhibits a three-stage change and the abrupt change points are the years 1981 and 2007: (1) 1968-1980, the runoff initially exhibited a trend of sustained decreasing and then an abrupt fluctuation. The runoff was obviously destroyed through precipitation-producing processes. Improper land utilisation and serious forest and grass destruction intensified the fluctuation variation amplitude of the runoff. (2) 1981-2006, the changing processes of runoff and precipitation exhibited good synchronism. Precipitation significantly affected runoff variation and human activities had a slight interference degree. (3) 2007-2013, the fluctuation range of runoff was considerably smaller than that of precipitation. The significant growth of forest and grassland areas and the increase in water consumption mitigated runoff fluctuation and greatly diminished runoff variation amplitude. According to calculation, the relative contribution rates of precipitation and human activities to net runoff variation with 1981-2007 as the reference period were -81% and 181% in average, respectively, during 1968-1980, and -117% and 217% in average, respectively, during 2007-2013. In general, the analysis of runoff variation trend and of the contribution rate of its main influencing factors in the typical karst watershed for nearly half a century may be significant to solve the drought problem in the karst

  8. Can longer forest harvest intervals increase summer streamflow for salmon recovery?

    Science.gov (United States)

    The Mashel Streamflow Modeling Project in the Mashel River Basin, Washington, is using a watershed-scale ecohydrological model to assess whether longer forest harvest intervals can remediate summer low flow conditions that have contributed to sharply reduced runs of spawning Chin...

  9. Watershed assessment-watershed analysis: What are the limits and what must be considered

    Science.gov (United States)

    Robert R. Ziemer

    2000-01-01

    Watershed assessment or watershed analysis describes processes and interactions that influence ecosystems and resources in a watershed. Objectives and methods differ because issues and opportunities differ.

  10. 50 years of change at 14 headwater snowmelt-dominated watersheds in Wyoming

    Science.gov (United States)

    Voutchkova, D. D.; Miller, S. N.

    2017-12-01

    Wyoming is a headwater state contributing to the water resources of four major US basins: Columbia River, Colorado River, Great Basin, and Missouri River. Most of the annual precipitation in this semi-arid state is received at high elevations as snow. Water availability for drinking water supply, reservoir storage, industrial, agricultural, and ecological needs - all depends on the variable and potentially changing annual snowmelt. Thus, characterizing snowmelt and snowmelt-dominated runoff variability and change at high-elevation headwater watersheds in Wyoming is of utmost importance. Next to quantifying variability and changes in total precipitation, snow-water equivalent (SWE), annual runoff and low flows at 14 selected and representative high-elevation watersheds during the previous 50 years, we also explore past watershed disturbances. Wildfires, forest management (e.g. timber harvest), and recent bark beetle outbakes have altered the vegetation and potentially the hydrology of these high-elevation watersheds. We present a synthesis and trend analysis of 49-75 complete water years (wy) of daily streamflow data for 14 high-elevation watersheds, 25-36 complete wy of daily SWE and precipitation data for the closest SNOTEL stations, and spatiotemporal data on burned areas for 20 wy, tree mortality for 18 wy, timber harvest during the 20th century, as well as overview on legacy tie-drive related distrbances. These results are discussed with respect to the differing watershed characteristics in order to present a spectrum of possible hydrologic responses. The importance of our work lies in extending our understanding of snowmelt headwater annual runoff and low-flow dynamics in Wyoming specifically. Such regional synthesis would inform and facilitate water managers and planners both at local state-wide level, but also in the intermountain US West.

  11. Application of Watershed Scale Models to Predict Nitrogen Loading From Coastal Plain Watersheds

    Science.gov (United States)

    George M. Chescheir; Glenn P Fernandez; R. Wayne Skaggs; Devendra M. Amatya

    2004-01-01

    DRAINMOD-based watershed models have been developed and tested using data collected from an intensively instrumented research site on Kendricks Creek watershed near Plymouth. NC. These models were applied to simulate the hydrology and nitrate nitrogen (NO3-N) loading from two other watersheds in the Coastal Plain of North Carolina, the 11600 ha Chicod Creek watershed...

  12. Changing Forestry Policy by Integrating Water Aspects into Forest/Vegetation Restoration in Dryland Areas in China

    Institute of Scientific and Technical Information of China (English)

    WANG Yanhui; Mike Bonell; Karl-Heinz Feger; YU Pengtao; XIONG Wei; XU Lihong

    2012-01-01

    Restoration forestry (forest rehabilitation) or re-vegetation is one effective measure to solve environmental problems, notably soil erosion. It may be further stimulated by the Clean Development Mechanism for carbon sequestration. However, there is an intensive and on-going debate about the adverse effects arising from afforestation in dryland areas, such as soil drying up which may cause further damage to the success of forest restoration, and the water yield reduction from watershed which may harm the regional development. On other hand, some preliminary studies showed a possibility that these adverse effects may be diminished more or less by properly designing the system structure and spatial distribution of forest/vegetation in a watershed. However, it is urgent to develop an evidence-based and sustainable new forestry policy for harmonizing forest-water interrelation. As a leading country in afforestation, China is beginning to develop a more trans-disciplinary and cross-sectoral forestry policy for harmonizing forestry development with water management. The main points of the changing new forestry policy should include: (1) Establishing a regional development strategy focusing on harmonized forest-water relations; (2) Taking forest-water interactions as an important part of evaluation; (3) Reducing the 'eco-water' quota of forests through technical advancement; (4) Developing and extending water-adaptive forest management practices; (S) Strengthening forest ecohydrological research and decision support ability.

  13. Calcium amendment may increase hydraulic efficiency and forest evapotranspiration

    Science.gov (United States)

    Kevin T. Smith; Walter C. Shortle

    2013-01-01

    Green et al. (1) report 2 y of increased evapotranspiration (ET; calculated as the difference between total precipitation and total runoff) and decreased water yield following watershed-scale amendment of soil with wollastonite (CaSiO3) at the Hubbard Brook Experimental Forest in the White Mountains of New Hampshire. The...

  14. Habitat typing versus advanced vegetation classification in western forests

    Science.gov (United States)

    Tony Kusbach; John Shaw; James Long; Helga Van Miegroet

    2012-01-01

    Major habitat and community types in northern Utah were compared with plant alliances and associations that were derived from fidelity- and diagnostic-species classification concepts. Each of these classification approaches was associated with important environmental factors. Within a 20,000-ha watershed, 103 forest ecosystems were described by physiographic features,...

  15. Evaluating Hydrologic Response of an Agricultural Watershed for Watershed Analysis

    OpenAIRE

    Manoj Kumar Jha

    2011-01-01

    This paper describes the hydrological assessment of an agricultural watershed in the Midwestern United States through the use of a watershed scale hydrologic model. The Soil and Water Assessment Tool (SWAT) model was applied to the Maquoketa River watershed, located in northeast Iowa, draining an agriculture intensive area of about 5,000 km2. The inputs to the model were obtained from the Environmental Protection Agency’s geographic information/database system called Better Assessment Science...

  16. Engaging Watershed Stakeholders for Cost-Effective Environmental Management Planning with "Watershed Manager"

    Science.gov (United States)

    Williams, Jeffery R.; Smith, Craig M.; Roe, Josh D.; Leatherman, John C.; Wilson, Robert M.

    2012-01-01

    "Watershed Manager" is a spreadsheet-based model that is used in extension education programs for learning about and selecting cost-effective watershed management practices to reduce soil, nitrogen, and phosphorus losses from cropland. It can facilitate Watershed Restoration and Protection Strategy (WRAPS) stakeholder groups' development…

  17. Modeling hydrologic responses to deforestation/forestation and climate change at multiple scales in the Southern US and China

    Science.gov (United States)

    Ge Sun; Steven McNulty; Jianbiao Lu; James Vose; Devendra Amayta; Guoyi Zhou; Zhiqiang Zhang

    2006-01-01

    Watershed management and restoration practices require a clear understanding of the basic eco-hydrologic processes and ecosystem responses to disturbances at multiple scales (Bruijnzeel, 2004; Scott et al., 2005). Worldwide century-long forest hydrologic research has documented that deforestation and forestation (i.e. reforestation and afforestation) can have variable...

  18. Effects of Environmental and Anthropogenic Factors on Water Quality in the Rock Creek Watershed

    Science.gov (United States)

    2016-04-08

    affecting health. With the development of public health informatics, public health professionals are realizing the benefits of applying GIS to...as hiking , boating, and year-round fishing. This portion of the watershed is densely forested, comprising of approximately 5,000 acres, with about...Beach Drive, whose sections through RCNP are closed to vehicles on the weekends. Other activities in the park include hiking , horseback riding

  19. Interim report on the scientific investigations in the Animas River watershed, Colorado to facilitate remediation decisions by the U.S. Bureau of Land Management and the U.S. Forest Service, March 29, 2000 meeting, Denver, Colorado

    Science.gov (United States)

    ,

    2000-01-01

    INTRODUCTION The joint U.S. Department of the Interior and U.S. Department of Agriculture Abandoned Mine Lands Initiative (AMLI) was developed as a collaborative effort between the Federal land management agencies (FLMA, that is the U.S. Bureau of Land Management and the U.S. Forest Service) and the U.S. Geological Survey (USGS) in 1996. The stated goal of the AML Initiative was to develop a strategy for gathering and communicating the scientific information needed to develop effective and cost-efficient remediation of abandoned mines within the framework of a watershed. Four primary objectives of the AMLI are to: 1. Provide the scientific information needed (in the short-term) by the FLMAs to make decisions related to the design and implementation of cleanup actions, 2. Develop a multi-disciplined, multi-division approach that integrates geologic, hydrologic, geochemical and ecological information into a knowledge base for sound decision making, 3. Transfer technologies developed within the scientific programs of the USGS to the field and demonstrate their suitability to solve real, practical problems, and 4. Establish working relationships among involved members of land management and regulatory agencies within the framework of a watershed approach to the cleanup of abandoned mines. Long-term process-based research, including development of analytical tools, is recognized as being critical to the long-term success in remediating watersheds impacted by historical mining activities (AML 5-year plan, http://amli.usgs.gov/amli). In a meeting of Federal agencies (U.S. Bureau of Land Management [BLM], U.S. Bureau of Reclamation [BOR], U.S. National Park Service [NPS], U.S. Forest Service [USFS], the U.S. Environmental Protection Agency [EPA], the U.S. Fish and Wildlife Service [F&WS]), and State agencies (Colorado Division of Public Health and Environment, Colorado Division of Mines and Geology), several watersheds were examined within the state whose water quality was

  20. Hydrograph separation techniques in snowmelt-dominated watersheds

    Science.gov (United States)

    Miller, S.; Miller, S. N.

    2017-12-01

    This study integrates hydrological, geochemical, and isotopic data for a better understanding of different streamflow generation pathways and residence times in a snowmelt-dominated region. A nested watershed design with ten stream gauging sites recording sub-hourly stream stage has been deployed in a snowmelt-dominated region in southeastern Wyoming, heavily impacted by the recent bark beetle epidemic. LiDAR-derived digital elevation models help elucidate effects from topography and watershed metrics. At each stream gauging site, sub-hourly stream water conductivity and temperature data are also recorded. Hydrograph separation is a useful technique for determining different sources of runoff and how volumes from each source vary over time. Following previous methods, diurnal cycles from sub-hourly recorded streamflow and specific conductance data are analyzed and used to separate hydrographs into overland flow and baseflow components, respectively. A final component, vadose-zone flow, is assumed to be the remaining water from the total hydrograph. With access to snowmelt and precipitation data from nearby instruments, runoff coefficients are calculated for the different mechanisms, providing information on watershed response. Catchments are compared to understand how different watershed characteristics translate snowmelt or precipitation events into runoff. Portable autosamplers were deployed at two of the gauging sites for high-frequency analysis of stream water isotopic composition during peak flow to compare methods of hydrograph separation. Sampling rates of one or two hours can detect the diurnal streamflow cycle common during peak snowmelt. Prior research suggests the bark beetle epidemic has had little effect on annual streamflow patterns; however, several results show an earlier shift in the day of year in which peak annual streamflow is observed. The diurnal cycle is likely to comprise a larger percentage of daily streamflow during snowmelt in post

  1. Response of mercury in an Adirondack (NY, USA) forest stream to watershed lime application

    Science.gov (United States)

    Millard, Geoffrey D.; Driscoll, Charles T.; Burns, Douglas; Montesdeoca, Mario R.; Murray, Karen

    2018-01-01

    Surface waters in Europe and North America previously impacted by acid deposition are recovering in conjunction with declining precursor emissions since the 1980s. Lime has been applied to some impacted watersheds to accelerate recovery. The response to liming can be considered a proxy for future recovery from acid deposition. Increases in dissolved organic carbon concentrations have been observed in surface waters in response to increased pH associated with recovery from acid deposition. Although not previously described, recovery-related increases in dissolved organic carbon could drive increases in mercury concentrations and loads because of the affinity of mercury for dissolved organic matter. We used a before–after impact-response approach to describe the response of stream mercury cycling to the application of lime to the watershed of a small stream in the Adirondack Mountains of New York, USA. Dissolved organic carbon, total mercury and methylmercury concentrations increased

  2. Best Management Practices for sediment control in a Mediterranean agricultural watershed

    Science.gov (United States)

    Abdelwahab, Ossama M. M.; Bingner, Ronald L.; Milillo, Fabio; Gentile, Francesco

    2015-04-01

    Soil erosion can lead to severe destruction of agricultural sustainability that affects not only productivity, but the entire ecosystem in the neighboring areas. Sediments transported together with the associated nutrients and chemicals can significantly impact downstream water bodies. Various conservation and management practices implemented individually or integrated together as a system can be used to reduce the negative impacts on agricultural watersheds from soil erosion. Hydrological models are useful tools for decision makers when selecting the most effective combination of management practices to reduce pollutant loads within a watershed system. The Annualized Agricultural Non-point Source (AnnAGNPS) pollutant loading management model can be used to analyze the effectiveness of diverse management and conservation practices that can control or reduce the impact of soil erosion processes and subsequent sediment loads in agricultural watersheds. A 506 km2 Mediterranean medium-size watershed (Carapelle) located in Apulia, Southern Italy was used as a case study to evaluate the model and best management practices (BMPs) for sediment load control. A monitoring station located at the Ordona bridge has been instrumented to continuously monitor stream flow and suspended sediment loads. The station has been equipped with an ultrasound stage meter and a stage recorder to monitor stream flow. An infrared optic probe was used to measure suspended sediment concentrations (Gentile et al., 2010 ). The model was calibrated and validated in the Carapelle watershed on an event basis (Bisantino et al., 2013), and the validated model was used to evaluate the effectiveness of BMPs on sediment reduction. Various management practices were investigated including evaluating the impact on sediment load of: (1) converting all cropland areas into forest and grass covered conditions; (2) converting the highest eroding cropland areas to forest or grass covered conditions; and (3

  3. Long-Term Forest Hydrologic Monitoring in Coastal Carolinas

    Science.gov (United States)

    Devendra M. Amatya; Ge Sun; Carl C. Trettin; R. Wayne Skaggs

    2003-01-01

    Long-term hydrologic data are essential for understanding the hydrologic processes, as base line data for assessment of impacts and conservation of regional ecosystems, and for developing and testing eco-hydrological models. This study presents 6-year (1996-2001) of rainfall, water table and outflow data from a USDA Forest Service coastal experimental watershed on a...

  4. Effectiveness monitoring for the aquatic and riparian component of the Northwest Forest Plan: conceptual framework and options.

    Science.gov (United States)

    Gordon H. Reeves; David B. Hohler; David P. Larsen; David E. Busch; Kim Kratz; Keith Reynolds; Karl F. Stein; Thomas Atzet; Polly Hays; Michael. Tehan

    2004-01-01

    An Aquatic and Riparian Effectiveness Monitoring Plan (AREMP) for the Northwest Forest Plan is intended to characterize the ecological condition of watersheds and aquatic ecosystems. So to determine the effectiveness of the Northwest Forest Plan to meet relevant objectives, this report presents the conceptual foundation of options for use in pilot testing and...

  5. Watershed-based survey designs

    Science.gov (United States)

    Detenbeck, N.E.; Cincotta, D.; Denver, J.M.; Greenlee, S.K.; Olsen, A.R.; Pitchford, A.M.

    2005-01-01

    Watershed-based sampling design and assessment tools help serve the multiple goals for water quality monitoring required under the Clean Water Act, including assessment of regional conditions to meet Section 305(b), identification of impaired water bodies or watersheds to meet Section 303(d), and development of empirical relationships between causes or sources of impairment and biological responses. Creation of GIS databases for hydrography, hydrologically corrected digital elevation models, and hydrologic derivatives such as watershed boundaries and upstream–downstream topology of subcatchments would provide a consistent seamless nationwide framework for these designs. The elements of a watershed-based sample framework can be represented either as a continuous infinite set defined by points along a linear stream network, or as a discrete set of watershed polygons. Watershed-based designs can be developed with existing probabilistic survey methods, including the use of unequal probability weighting, stratification, and two-stage frames for sampling. Case studies for monitoring of Atlantic Coastal Plain streams, West Virginia wadeable streams, and coastal Oregon streams illustrate three different approaches for selecting sites for watershed-based survey designs.

  6. Evaluation of forest management practices through application of a biogeochemical model, PnET-BGC

    Science.gov (United States)

    Valipour, M.; Driscoll, C. T.; Johnson, C. E.; Campbell, J. L.; Fahey, T.; Zeng, T.

    2017-12-01

    Forest ecosystem response to logging disturbance varies significantly, depending on site conditions, species composition, land use history, and the method and frequency of harvesting. The long-term effects of forest cuttings are less clear due to limited information on land use history and long-term time series observations. The hydrochemical model, PnET-BGC was modified and verified using field data from multiple experimentally harvested northern hardwood watersheds at the Hubbard Brook Experimental Forest (HBEF), New Hampshire, USA, including a commercial whole-tree harvest (Watershed 5), a devegetation experiment (Watershed 2; devegetation and herbicide treatment), a commercial strip-cut (Watershed 4) to simulate the hydrology, biomass accumulation, and soil solution and stream water chemistry responses to clear-cutting. The confirmed model was used to investigate temporal changes in aboveground biomass accumulation and nutrient dynamics under three different harvesting intensities (40%, 60%, 80%) over four varied rotation lengths (20, 40, 60, 80 years) with results compared with a scenario of no forest harvesting. The total ecosystem carbon pool (biomass, soil and litter) was reduced over harvesting events. The greatest decline occurred in litter by 40%-70%, while the pool of carbon stored in aboveground biomass decreased by 30%-60% for 80% cutting levels at 40 and 20 year rotation lengths, respectively. The large pool of soil organic carbon remained relatively stable, with only minor declines over logging regimes. Stream water simulations demonstrated increased loss of major elements over cutting events. Ca+2 and NO3- were the most sensitive elements to leaching over frequent intensive logging. Accumulated leaching of Ca+2 and NO3- varied between 90-520 t Ca/ha and 40-420 t N/ha from conservative (80-year period and 40% cutting) to aggressive (20-year period and 80% cutting) cutting regimes, respectively. Moreover, a reduction in nutrient plant uptake over

  7. Watershed Central: Harnessing a social media tool to organize local technical knowledge and find the right watershed resources for your watershed

    Science.gov (United States)

    Watershed Central was developed to be a bridge between sharing and searching for information relating to watershed issues. This is dependent upon active user support through additions and updates to the Watershed Central Wiki. Since the wiki is user driven, the content and applic...

  8. Elevation dependent sensitivity of northern hardwoods to Ca addition at Hubbard Brook Experimental Forest, NH USA

    Science.gov (United States)

    Rakesh Minocha; Stephanie Long; Palaniswamy Thangavel; Subhash C. Minocha; Christopher Eagar; Charles T. Driscoll

    2010-01-01

    Acidic deposition has caused a depletion of calcium (Ca) in the northeastern forest soils. Wollastonite (Ca silicate) was added to watershed 1 (WS1) at the Hubbard Brook Experimental Forest (HBEF) in 1999 to evaluate its effects on various functions of the HBEF ecosystem. The effects of Ca addition on foliar soluble (extractable in 5% HClO4) ions...

  9. Culturally and economically important nontimber forest products of northern Maine

    Science.gov (United States)

    Michelle J. Baumflek; Marla R. Emery; Clare. Ginger

    2010-01-01

    Nontimber forest products (NTFPs) gathered for food, medicine, craft, spiritual, aesthetic, and utilitarian purposes make substantial contributions to the economic viability and cultural vitality of communities. In the St. John River watershed of northern Maine, people identifying with cultural groups including Acadian, Maliseet, Mi'kmaq, Scotch-Irish, and Swedish...

  10. Frequency of streamflow measurements required to determine forest treatment effects

    Science.gov (United States)

    Kenneth G. Reinhart

    1964-01-01

    Most of the stream-discharge records for our experimental watersheds are taken by continuous measurements. But the question arises: are continuous measurements necessary to determine effects of forest treatments? Or could treatment effects be determined by measurement of discharge at intervals, say, once a day or once a week?

  11. Estimating the erosion and deposition rates in a small watershed by the {sup 137}Cs tracing method

    Energy Technology Data Exchange (ETDEWEB)

    Li Mian [Yellow River Institute of Hydraulic Research, Key Laboratory of Sediment Research of Yellow River of Ministry of Water Resources, Zhengzhou, Henan 450003 (China)], E-mail: hnli-mian@163.com; Li Zhanbin [Xi' an University of Technology, Xi' an, Shaanxi 710048 (China); Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi 712100 (China); Yao Wenyi [Yellow River Institute of Hydraulic Research, Key Laboratory of Sediment Research of Yellow River of Ministry of Water Resources, Zhengzhou, Henan 450003 (China); Liu Puling [Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi 712100 (China)

    2009-02-15

    Understanding the erosion and deposition rates in a small watershed is important for designing soil and water conservation measures. The objective of this study is to estimate the net soil loss and gain at points with various land use types and landform positions in a small watershed in the Sichuan Hilly Basin of China by the {sup 137}Cs tracing technique. Among various land use types, the order of erosion rate was bare rock > sloping cultivated land > forest land. The paddy field and Caotu (a kind of cultivated land located at the foot of hills) were depositional areas. The erosion rate under different landform was in this order: hillside > saddle > hilltop. The footslope and the valley were depositional areas. The {sup 137}Cs technique was shown to provide an effective means of documenting the spatial distribution of soil erosion and deposition within the small watershed.

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

    International Nuclear Information System (INIS)

    Kwon, Sae Yun; Blum, Joel D.; Nadelhoffer, Knute J.; Timothy Dvonch, J.; Tsui, Martin Tsz-Ki

    2015-01-01

    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 202 Hg and Δ 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 202 Hg and Δ 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 202 Hg and Δ 199 Hg values estimated for IHg are consistent with other studies that measured forest floor in temperate forests. The Δ 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 202 Hg and Δ 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 199 Hg values for high trophic level insects and compared these insects at multiple distances perpendicular to the lake shoreline. The Δ 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 importance of MMHg sources and complex Hg transfer

  13. 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

  14. Post-Fire soil water repellency, hydrologic response, and sediment yield compared between grass-converted and chaparral watersheds

    Science.gov (United States)

    Ken R. Hubbert; Pete M. Wohlgemuth; Jan L. Beyers; Marcia G. Narog; Ross Gerrard

    2012-01-01

    In 2002, the Williams Fire burned >90 % of the San Dimas Experimental Forest, providing an opportunity to investigate differences in soil water repellency, peak discharge, and sediment yield between grass-converted and chaparral watersheds. Post-fire water repellency and moisture content were measured in the winter and summer for four years. Peak discharge was...

  15. Seasonal rainfall-runoff relationships in a lowland forested watershed in the southeastern USA

    Science.gov (United States)

    Ileana La Torre Torres; Devendra Amatya; Ge Sun; Timothy Callahan

    2011-01-01

    Hydrological processes of lowland watersheds of the southern USA are not well understood compared to a hilly landscape due to their unique topography, soil compositions, and climate. This study describes the seasonal relationships between rainfall patterns and runoff (sum of storm flow and base flow) using 13 years (1964–1976) of rainfall and stream flow data for a low...

  16. The experimental watersheds in Slovenia

    International Nuclear Information System (INIS)

    Sraj, M; Rusjan, S; Petan, S; Vidmar, A; Mikos, M; Globevnik, L; Brilly, M

    2008-01-01

    Experimental watersheds are critical to the advancement of hydrological science. By setting up three experimental watersheds, Slovenia also obtained its grounds for further development of the science and discipline. In the Dragonja experimental watershed the studies are focused on the afforestation of the watershed in a mediterranean climate, on the Reka river the water balance in a partly karstic area is examined, and on the case of the Glinscica stream the implications of the urban environment are studied. We have obtained valuable experience and tested new measuring equipment on all three experimental watersheds. Measurements and analysis on the experimental watersheds improved the current understanding of hydrological processes. They resulted in several PhD Theses, Master Theses and scientific articles. At the same time the experimental watersheds provide support to the teaching and studying process.

  17. Lessons From Watershed-Based Climate Smart Agricultural Practices In Jogo-Gudedo Watershed Ethiopia

    Directory of Open Access Journals (Sweden)

    Abera Assefa

    2015-08-01

    Full Text Available Abstract Land degradation is the most chronic problem in the Ethiopia. Soil erosion and denudation of vegetation covers are tending to enlarge the area of degraded and west land in semi-arid watersheds. It is therefore watershed management is believed as a holistic approach to create a climate smart landscape that integrate forestry agriculture pasture and soil water management with an objective of sustainable management of natural resources to improve livelihood. This approach pursues to promote interactions among multiple stakeholders and their interests within and between the upstream and downstream locations of a watershed. Melkassa Agricultural Research Centre MARC has been implementing integrated watershed management research project in the Jogo-gudedo watershed from 2010-2014 and lessons from Jogo-gudedo watershed are presented in this research report. Participatory action research PAR was implemented on Soil and Water Conservation SWC area enclosure Agroforestry AF Conservation Tillage CT energy saving stove drought resistance crop varieties in the Jogo-gudedo watershed. Empirical research and action research at plot level and evaluation of introduced technologies with farmers through experimental learning approach and documentation were employed. The participatory evaluation and collective action of SWC and improved practices brought high degree of acceptance of the practices and technologies. This had been ratified by the implementation of comprehensive watershed management action research which in turn enabled to taste and exploit benefits of climate-smart agricultural practices. Eventually significant reduction on soil loss and fuel wood consumption improvements on vegetation cover and crop production were quantitatively recorded as a good indicator and success. Field visit meetings trainings and frequent dialogues between practitioners and communities at watershed level have had a help in promoting the climate smart agriculture

  18. Stream Nitrate Concentrations Diverge at Baseflow and Converge During Storms in Watersheds with Contrasting Urbanization

    Science.gov (United States)

    Carey, R. O.; Wollheim, W. M.; Mulukutla, G. K.; Cook, C. S.

    2013-12-01

    Management of non-point sources is challenging because it requires adequate quantification of non-point fluxes that are highly dynamic over time. Most fluxes occur during storms and are difficult to characterize with grab samples alone in flashy, urban watersheds. Accurate and relatively precise measurements using in situ sensor technology can quantify fluxes continuously, avoiding the uncertainties in extrapolation of infrequently collected grab samples. In situ nitrate (NO3-N) sensors were deployed simultaneously from April to December 2013 in two streams with contrasting urban land uses in an urbanizing New Hampshire watershed (80 km2). Nitrogen non-point fluxes and temporal patterns were evaluated in Beards Creek (forested: 50%; residential: 24%; commercial/institutional/transportation: 7%; agricultural: 6%) and College Brook (forested: 35%; residential: 11%; commercial/institutional/transportation: 20%; agricultural: 17%). Preliminary data indicated NO3-N concentrations in Beards Creek (mean: 0.37 mg/L) were lower than College Brook (mean: 0.60 mg/L), but both streams exhibited rapid increases in NO3-N during the beginning of storms followed by overall dilution. While baseflow NO3-N was greater in College Brook than Beards Creek, NO3-N at the two sites consistently converged during storms. This suggests that standard grab sampling may overestimate fluxes in urban streams, since short-term dilution occurred during periods of highest flow. Analyzing NO3-N flux patterns in smaller urban streams that are directly impacted by watershed activities could help to inform management decisions regarding N source controls, ultimately allowing an assessment of the interactions of climate variability and management actions.

  19. Streamflow variation of forest covered catchments

    Science.gov (United States)

    Gribovszki, Z.; Kalicz, P.; Kucsara, M.

    2003-04-01

    Rainfall concentration and runoff, otherwise rainfall-runoff processes, which cause river water discharge fluctuation, is one of the basic questions of hydrology. Several social-economy demands have a strong connection with small or bigger rivers from the point of view both quantity and quality of the water. Gratification or consideration of these demands is complicated substantially that we have still poor knowledge about our stream-flow regime. Water resources mainly stem from upper watersheds. These upper watersheds are the basis of the water concentration process; therefore we have to improve our knowledge about hydrological processes coming up in these territories. In this article we present runoff regime of two small catchments on the basis of one year data. Both catchments have a similar magnitude 0.6 and 0.9 km^2. We have been analyzed in detail some hydrological elements: features of rainfall, discharge, rainfall induced flooding waves and basic discharge in rainless periods. Variances of these parameters have been analyzed in relation to catchments surface, vegetation coverage and forest management. Result data set well enforce our knowledge about small catchments hydrological processes. On the basis of these fundamentals we can plan more established the management of these lands (forest practices, civil engineering works, and usage of natural water resources).

  20. Recommendations for constructing forest stream crossings to control soil losses

    Science.gov (United States)

    Pamela J. Edwards; Jingxin Wang; Joshua T. Stedman

    2009-01-01

    Stream water samples were collected once daily and throughout storms from a small forested watershed in north central West Virginia for approximately 8 years. The turbidities of the samples were measured to determine how water quality changed in response to the construction of three associated stream crossings. The influence of the...

  1. Predicting watershed acidification under alternate rainfall conditions

    International Nuclear Information System (INIS)

    Huntington, T.G.

    1996-01-01

    The effect of alternate rainfall scenarios on acidification of a forested watershed subjected to chronic acidic deposition was assessed using the model of acidification of groundwater in catchments (MAGIC). The model was calibrated at the Panola Mountain Research Watershed, near Atlanta, Georgia, USA using measured soil properties, wet and dry deposition, and modeled hydrologic routing. Model forecast simulations were evaluated to compare alternate temporal averaging of rainfall inputs and variations in rainfall amount and seasonal distribution. Soil water alkalinity was predicted to decrease to substantially lower concentrations under lower rainfall compared with current or higher rainfall conditions. Soil water alkalinity was also predicted to decrease to lower levels when the majority of rainfall occurred during the growing season compared with other rainfall distributions. Changes in rainfall distribution that result in decreases in net soil water flux will temporarily delay acidification. Ultimately, however, decreased soilwater flux will result in larger increases in soil-adsorbed sulfur and soil-water sulfate concentrations and decreases in alkalinity when compared to higher water flux conditions. Potential climate change resulting in significant changes in rainfall amounts, seasonal distributions of rainfall, or evapotranspiration will change net soil water flux and, consequently, will affect the dynamics of the acidification response to continued sulfate loading. 29 refs., 7 figs., 4 tabs

  2. South Fork Salmon River Watershed Restoration, 2008-2009 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Reaney, Mark D. [Nez Perce Tribe Department of Fisheries Resource Management

    2009-04-15

    The watershed restoration work elements within the project area, the South Fork Salmon River Watershed, follow the watershed restoration approach adopted by the Nez Perce Tribe Department of Fisheries Resource Management (DFRM) - Watershed Division. The vision of the Nez Perce Tribe DFRM-Watershed Division focuses on protecting, restoring, and enhancing watersheds and treaty resources within the ceded territory of the Nez Perce Tribe under the Treaty of 1855 with the United States Federal Government. The program uses a holistic approach, which encompasses entire watersheds, ridge top to ridge top, emphasizing all cultural aspects and strategies that rely on natural fish production and healthy river ecosystems. The Nez Perce Tribe DFRM-Watershed Division strives towards maximizing historic ecosystem productivity and health for the restoration of anadromous and resident fish populations and the habitat on which all depend on for future generations Originally, this project was funded to create a step/pool stream channel that was appropriate to restore fish passage where the 'Glory Hole Cascade' is currently located at the Stibnite Mine. Due to unforeseen circumstances at the time, the project is unable to move forward as planned and a request for a change in scope of the project and an expansion of the geographic area in which to complete project work was submitted. No additional funds were being requested. The ultimate goal of this project is to work with the holistic, ridge top to ridge top approach to protect and restore the ecological and biological functions of the South Fork Salmon River Watershed to assist in the recovery of threatened and endangered anadromous and resident fish species. FY 2008 Work Elements included two aquatic organism passage (AOP) projects to restore habitat connectivity to two fish-bearing tributaries to the East Fork South Fork Salmon River, Salt and Profile Creeks. The Work Elements also included road survey and assessment

  3. Adopt Your Watershed

    Data.gov (United States)

    U.S. Environmental Protection Agency — Adopt Your Watershed is a Website that encourages stewardship of the nation's water resources and serves as a national inventory of local watershed groups and...

  4. Forest management to protect Colorado’s water resources: A synthesis report to support House Bill 16-1255

    Science.gov (United States)

    Niah B. H. Venable; Ryan Lockwood; Joseph DiMaria; Joseph Duda; Chuck Rhoades; Lisa Mason

    2017-01-01

    The Colorado Water Plan is a collaborative framework that sets forth objectives, goals and actions by which Coloradans can collectively address current and future water challenges through feasible and innovative solutions. As a majority of the state’s water supply flows from forested watersheds, the Colorado State Forest Service (CSFS), a service and outreach agency of...

  5. ACIDIFICATION TRENDS AND THE EVOLUTION OF NEUTRALIZATION MECHANISMS THROUGH TIME AT THE BEAR BROOK WATERSHED IN MAINE (BBWM), U.S.A.

    Science.gov (United States)

    The paired catchment study at the forested Bear Brook Watershed in Maine (BBWM) U.S.A. documents interactions among short- to long-term processes of acidification. In 1987-1989, runoff from the two catchments was nearly identical in quality and quantity. Ammonium sulfate has been...

  6. 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.

  7. Impact of Soil and Water Conservation Interventions on Watershed Runoff Response in a Tropical Humid Highland of Ethiopia.

    Science.gov (United States)

    Sultan, Dagnenet; Tsunekawa, Atsushi; Haregeweyn, Nigussie; Adgo, Enyew; Tsubo, Mitsuru; Meshesha, Derege Tsegaye; Masunaga, Tsugiyuki; Aklog, Dagnachew; Fenta, Ayele Almaw; Ebabu, Kindiye

    2018-05-01

    Various soil and water conservation measures (SWC) have been widely implemented to reduce surface runoff in degraded and drought-prone watersheds. But little quantitative study has been done on to what extent such measures can reduce watershed-scale runoff, particularly from typical humid tropical highlands of Ethiopia. The overall goal of this study is to analyze the impact of SWC interventions on the runoff response by integrating field measurement with a hydrological CN model which gives a quantitative analysis future thought. Firstly, a paired-watershed approach was employed to quantify the relative difference in runoff response for the Kasiry (treated) and Akusty (untreated) watersheds. Secondly, a calibrated curve number hydrological modeling was applied to investigate the effect of various SWC management scenarios for the Kasiry watershed alone. The paired-watershed approach showed a distinct runoff response between the two watersheds however the effect of SWC measures was not clearly discerned being masked by other factors. On the other hand, the model predicts that, under the current SWC coverage at Kasiry, the seasonal runoff yield is being reduced by 5.2%. However, runoff yields from Kasiry watershed could be decreased by as much as 34% if soil bunds were installed on cultivated land and trenches were installed on grazing and plantation lands. In contrast, implementation of SWC measures on bush land and natural forest would have little effect on reducing runoff. The results on the magnitude of runoff reduction under optimal combinations of SWC measures and land use will support decision-makers in selection and promotion of valid management practices that are suited to particular biophysical niches in the tropical humid highlands of Ethiopia.

  8. Old Growth Conifer Watersheds in the Western Cascades, Oregon: Sentinels of Climate Change

    Science.gov (United States)

    Miles, K. M.

    2011-12-01

    In the Pacific Northwest, where the majority of precipitation falls during the winter, mountain snowpacks provide an important source of streamflow during the dry summer months when water demands are frequently highest. Increasing temperatures associated with climate change are expected to result in a decline in winter snowpacks in western North America, earlier snowmelt, and subsequently a shift in the timing of streamflows, with an increasing fraction of streamflows occurring earlier in the water year and drier conditions during the summer. Long-term records from headwater watersheds in old growth conifer forest at the H. J. Andrews Experimental Forest (HJ Andrews), Oregon, provide the opportunity to examine changes in climate, vegetation, and streamflow. Continuous streamflow records have been collected since 1953, 1964, and 1969 from three small (8.5-60 ha) watersheds (WS2, WS8, and WS9). Over the 40- to 50-year period of study, late winter to early summer monthly average minimum temperatures have increased by 1-2°C, and spring snow water equivalent at a nearby Snotel site has declined, but monthly precipitation has remained unchanged. Spring runoff ratios have declined in by amounts equivalent to 0.59-2.45 mm day-1 at WS2, WS8, and WS9, which are comparable to estimated rates of stand-level transpiration from trees in these watersheds. However, winter runoff ratios have not changed significantly at either WS2 or WS9, and have actually decreased at WS8 by 2.43 mm day-1 over the period of record. Furthermore, summer runoff ratios have not changed significantly at either WS8 or WS9, and have increased at WS2 by 0.34 mm day-1 over the period of record. These findings suggest that warming temperatures have resulted in a reduction in spring snowpacks and an earlier onset of evapotranspiration in the spring when soil moisture is abundant, but physiological responses of these conifer forests to water stress and water surplus may mitigate or exceed the expression of a

  9. A method of fingerprinting the sources of fluvial sediment using environmental radionuclides. A case study of Tsuzura river watershed

    International Nuclear Information System (INIS)

    Mizugaki, Shigeru; Onda, Yuichi; Fukuyama, Taijiro; Koga, Satoko; Hiramatsu, Shinya

    2006-01-01

    To study the fluvial sediment sources in forested watershed in Shikoku Island, Japan, the concentration of Cs-137 and Pb-210 ex and U decay series radionuclides were analyzed. The study area in the midstream of Shimanto River basin, located 700 km southwest of Tokyo. The 0.33 km 2 area watershed ranges in elevation from 170 m to 560 m above sea level. The soil sampling was conducted in hillslopes in various locations such as landslide scar, soil surface in unmanaged Hinoki (Chamacecyparis obtusa) plantation and unsealed forest road, and detailed sampling in the stream bed and bank was also conducted in several tributaries. Time-integrated suspended sediment sampler was adopted to obtain enough volume of sample to determine the radionuclides. The activities of Cs-137, Pb-210, Pb-214 and Bi-214 of soils and fluvial sediments were determined by gamma-ray spectrometry. Correction for the effect of particle size distribution and organic matter content on the radionuclides were conducted to compare the radionuclides concentration between the soils of potential suspended sediment sources and fluvial sediments. It was found that there were significant differences of Cs-137 and Pb-210 ex concentration between forest floor or runoff sediment and forest road or stream bank. The Cs-137 and Pb-210 ex concentration of suspended sediment varied among them, suggesting the possibility of fingerprinting the sources of fluvial sediment by Cs-137 and Pb-210 ex . (author)

  10. Quantifying Stream Flux of Carbon Nitrogen and Phosphorus in a Tropical Watershed, Mae Sa Thailand

    Science.gov (United States)

    Benner, S. G.; Ziegler, A. D.; Tantasirin, C.; Lu, X.; Giambelluca, T.

    2006-12-01

    Nutrient loading to rivers and, ultimately, oceans is of global concern with implications for both immediate aquatic health and as a longer term feedback system for global elemental cycling and climate change. Southeast Asia has been identified as a global hotspot for high yields of C, N, and P. We present initial results from a nutrient flux study from the Mae Sa watershed in northern Thailand. The Mae Sa is a 74 ha basin at the headwaters of the Chao Praya River and is characterized by diverse land use extending from forest reserves to intensive agriculture. The watershed receives the majority of its annual 1300-2000 mm of precipitation during the monsoonal season with runoff characterized by high intensity, short-duration flooding, typically produced by localized, sub-watershed, precipitation events. Dissolved (1 mm) fractions were sampled across a series of storm hydrograph events and each fraction was analyzed for total organic C, N, and P contents. Initial results indicate that a significant fraction of the nutrient flux during these events is found in the >1 mm size fraction.

  11. Quantifying Sediment Transport in a Premontane Transitional Cloud Forest

    Science.gov (United States)

    Waring, E. R.; Brumbelow, J. K.

    2013-12-01

    Quantifying sediment transport is a difficult task in any watershed, and relatively little direct measurement has occurred in tropical, mountainous watersheds. The Howler Monkey Watershed (2.2 hectares) is located in a premontane transitional cloud forest in San Isidro de Peñas Blancas, Costa Rica. In June 2012, a V-notch stream-gaging weir was built in the catchment with a 8 ft by 6 ft by 4 ft concrete stilling basin. Sediment captured by the weir was left untouched for an 11 month time period. To collect the contents of the weir, the stream was rerouted and the weir was drained. The stilling basin contents were systematically sampled, and samples were taken to a lab and characterized using sieve and hydrometer tests. The wet volume of the remaining sediment was obtained, and dry mass was estimated. Particle size distribution of samples were obtained from lab tests, with 96% of sediment trapped by the weir being sand or coarser. The efficiency of the weir as a sediment collector was evaluated by comparing particle fall velocities to residence time of water in the weir under baseflow conditions. Under these assumptions, only two to three percent of the total mass of soil transported in the stream is thought to have been suspended in the water and lost over the V-notch. Data were compared to the Universal Soil Loss Equation (USLE), a widely accepted method for predicting soil loss in agricultural watersheds. As expected, application of the USLE to a tropical rainforest was problematic with uncertainty in parameters yielding a soil loss estimate varying by a factor of 50. Continued monitoring of sediment transport should yield data for improved methods of soil loss estimation applicable to tropical mountainous forests.

  12. Just passing through --- high Hg deposition to Puerto Rico forest moves quickly off the landscape

    Science.gov (United States)

    Shanley, J. B.; Willenbring, J. K.; Kaste, J. M.; Occhi, M.; McDowell, W. H.

    2012-12-01

    Atmospheric mercury (Hg) in wet deposition at the Luquillo Experimental Forest in northeastern Puerto Rico, averages 28 μg m-2 yr-1, higher than any site in the USA Mercury Deposition Network. Despite the high deposition, Hg content of soils, vegetation, and biota are below global averages. The low Hg content of watershed surfaces, coupled with exceptionally high stream total Hg flux, suggest that most of the Hg passes through the watershed with minimal retention. We assessed Hg dynamics in two adjacent watersheds, Rio Icacos underlain by quartz diorite, and Rio Mameyes underlain by volcaniclastic rocks. At both sites, high-flow Hg concentrations approached 100 ng L-1, dominated by particulate Hg. In order to assess the apparent pass-through nature of Hg in this tropical forest, we measured 7Be and 10Be isotopes from natural, cosmogenic fallout adsorbed on stream suspended particles to constrain the Hg age /residence time and source (atmospheric vs. geogenic or legacy Hg from 19th century gold mining). Ubiquitous 7Be (half-life 53 days) and relatively high 7Be/10Be ratios on suspended particles suggest that stream Hg was dominated by erosion from exposed surfaces, supporting a short residence time. The low watershed retention of the high Hg throughput limits adverse biological effects in this tropical ecosystem.

  13. Wind River Watershed Restoration Project; Underwood Conservation District, Annual Report 2002-2003.

    Energy Technology Data Exchange (ETDEWEB)

    White, Jim

    2004-02-01

    The goal of the Wind River project is to preserve, protect and restore Wind River steelhead. In March, 1998, the National Marine Fisheries Service listed the steelhead of the lower Columbia as 'threatened' under the Endangered Species Act. In 1997, the Washington Department of Fish and Wildlife rated the status of the Wind River summer run steelhead as critical. Due to the status of this stock, the Wind River summer steelhead have the highest priority for recovery and restoration in the state of Washington's Lower Columbia Steelhead Conservation Initiative. The Wind River Project includes four cooperating agencies. Those are the Underwood Conservation District (UCD), United States Geological Service (USGS), US Forest Service (USFS), and Washington State Department of Fish & Wildlife (WDFW). Tasks include monitoring steelhead populations (USGS and WDFW), Coordinating a Watershed Committee and Technical Advisory Group (UCD), evaluating physical habitat conditions (USFS and UCD), assessing watershed health (all), reducing road sediments sources (USFS), rehabilitating riparian corridors, floodplains, and channel geometry (UCD, USFS), evaluate removal of Hemlock Dam (USFS), and promote local watershed stewardship (UCD, USFS). UCD's major efforts have included coordination of the Wind River Watershed Committee and Technical Advisory Committee (TAC), water temperature and water chemistry monitoring, riparian habitat improvement projects, and educational activities. Our coordination work enables the local Watershed Committee and TAC to function and provide essential input to Agencies, and our habitat improvement work focuses on riparian revegetation. Water chemistry and temperature data collection provide information for monitoring watershed conditions and fish habitat, and are comparable with data gathered in previous years. Water chemistry information collected on Trout Creek should, with 2 years data, determine whether pH levels make conditions

  14. The role of interior watershed processes in improving parameter estimation and performance of watershed models.

    Science.gov (United States)

    Yen, Haw; Bailey, Ryan T; Arabi, Mazdak; Ahmadi, Mehdi; White, Michael J; Arnold, Jeffrey G

    2014-09-01

    Watershed models typically are evaluated solely through comparison of in-stream water and nutrient fluxes with measured data using established performance criteria, whereas processes and responses within the interior of the watershed that govern these global fluxes often are neglected. Due to the large number of parameters at the disposal of these models, circumstances may arise in which excellent global results are achieved using inaccurate magnitudes of these "intra-watershed" responses. When used for scenario analysis, a given model hence may inaccurately predict the global, in-stream effect of implementing land-use practices at the interior of the watershed. In this study, data regarding internal watershed behavior are used to constrain parameter estimation to maintain realistic intra-watershed responses while also matching available in-stream monitoring data. The methodology is demonstrated for the Eagle Creek Watershed in central Indiana. Streamflow and nitrate (NO) loading are used as global in-stream comparisons, with two process responses, the annual mass of denitrification and the ratio of NO losses from subsurface and surface flow, used to constrain parameter estimation. Results show that imposing these constraints not only yields realistic internal watershed behavior but also provides good in-stream comparisons. Results further demonstrate that in the absence of incorporating intra-watershed constraints, evaluation of nutrient abatement strategies could be misleading, even though typical performance criteria are satisfied. Incorporating intra-watershed responses yields a watershed model that more accurately represents the observed behavior of the system and hence a tool that can be used with confidence in scenario evaluation. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  15. INTEGRATED SUSTAINABLE MANGROVE FOREST MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Cecep Kusmana

    2015-07-01

    Full Text Available Mangrove forest as a renewable resource must be managed based on sustainable basis in which the benefits of ecological, economic and social from the forest have to equity concern in achieving the optimum forest products and services in fulfill the needs of recent generation without destruction of future generation needs and that does not undesirable effects on the physical and social environment. This Sustainable Forest Management (SFM practices needs the supporting of sustainability in the development of social, economic and environment (ecological sounds simultaneously, it should be run by the proper institutional and regulations. In operational scale, SFM need integration in terms of knowledge, technical, consultative of stakeholders, coordination among sectors and other stakeholders, and considerations of ecological inter-relationship in which mangroves as an integral part of both a coastal ecosystem and a watershed (catchment area. Some tools have been developed to measure the performent of SFM, such as initiated by ITTO at 1992 and followed by Ministry of Forestry of Indonesia (1993, CIFOR (1995, LEI (1999, FSC (1999, etc., however, the true nuance of SFM’s performance is not easy to be measured. 

  16. Runoff response to climate change and human activities in a typical karst watershed, SW China

    Science.gov (United States)

    Xu, Yan; Wang, Shijie; Shu, Dongcai; Tian, Yichao

    2018-01-01

    This study aims to reveal the runoff variation characteristics of long time series in a karst region, analyse comprehensively its different driving factors, and estimate quantitatively the contribution rates of climate change and human activities to net runoff variation. Liudong river basin, a typical karst watershed in southwest China, is the study site. Statistical methods, such as linear fitting, the Morlet wavelet analysis, normalized curve and double mass curve, are applied to analyse the runoff of the watershed. Results show that the runoff in the karst watershed during the research period exhibits a three-stage change and the abrupt change points are the years 1981 and 2007: (1) 1968–1980, the runoff initially exhibited a trend of sustained decreasing and then an abrupt fluctuation. The runoff was obviously destroyed through precipitation-producing processes. Improper land utilisation and serious forest and grass destruction intensified the fluctuation variation amplitude of the runoff. (2) 1981–2006, the changing processes of runoff and precipitation exhibited good synchronism. Precipitation significantly affected runoff variation and human activities had a slight interference degree. (3) 2007–2013, the fluctuation range of runoff was considerably smaller than that of precipitation. The significant growth of forest and grassland areas and the increase in water consumption mitigated runoff fluctuation and greatly diminished runoff variation amplitude. According to calculation, the relative contribution rates of precipitation and human activities to net runoff variation with 1981–2007 as the reference period were −81% and 181% in average, respectively, during 1968–1980, and −117% and 217% in average, respectively, during 2007–2013. In general, the analysis of runoff variation trend and of the contribution rate of its main influencing factors in the typical karst watershed for nearly half a century may be significant to solve the drought

  17. Turbidity as an Indicator of Water Quality in Diverse Watersheds of the Upper Pecos River Basin

    Directory of Open Access Journals (Sweden)

    Gregory M. Huey

    2010-06-01

    Full Text Available Microbial concentrations, total suspended solids (TSS and turbidity vary with stream hydrology and land use. Turbidity, TSS, and microbial concentrations, loads and yields from four watersheds were assessed: an unburned montane forest, a catastrophically burned montane forest, urban land use and rangeland prairie. Concentrations and loads for most water quality variables were greatest during storm events. Turbidity was an effective indicator of TSS, E. coli and Enterococci spp. The greatest threat to public health from microbial contamination occurs during storm runoff events. Efforts to manage surface runoff and erosion would likely improve water quality of the upper Pecos River basin in New Mexico, USA.

  18. 77 FR 55796 - Sand Lick Fork Watershed Restoration Project; Daniel Boone National Forest, KY

    Science.gov (United States)

    2012-09-11

    ..., conversion of 0.6 miles of Powell County Road 212 to Forest Service maintenance, conversion of 3.1 miles of..., 212A, 2045, 2120 and the section of county road to be transferred to Forest Service maintenance... miles of Powell County Road 212 to Forest Service maintenance, conversion of 3.1 miles of system roads...

  19. Analysis of nitrogen saturation potential in Rocky Mountain tundra and forest: implications for aquatic systems

    Science.gov (United States)

    Baron, Jill S.; Ojima, Dennis S.; Holland, Elisabeth A.; Parton, William J.

    1994-01-01

    We employed grass and forest versions of the CENTURY model under a range of N deposition values (0.02–1.60 g N m−2 y−1) to explore the possibility that high observed lake and stream N was due to terrestrial N saturation of alpine tundra and subalpine forest in Loch Vale Watershed, Rocky Mountain National Park, Colorado. Model results suggest that N is limiting to subalpine forest productivity, but that excess leachate from alpine tundra is sufficient to account for the current observed stream N. Tundra leachate, combined with N leached from exposed rock surfaces, produce high N loads in aquatic ecosystems above treeline in the Colorado Front Range. A combination of terrestrial leaching, large N inputs from snowmelt, high watershed gradients, rapid hydrologic flushing and lake turnover times, and possibly other nutrient limitations of aquatic organisms constrain high elevation lakes and streams from assimilating even small increases in atmospheric N. CENTURY model simulations further suggest that, while increased N deposition will worsen the situation, nitrogen saturation is an ongoing phenomenon.

  20. Watershed Fact Sheet: Improving Utah's Water Quality, Upper Bear River Watershed

    OpenAIRE

    Extension, USU

    2012-01-01

    The Upper Watershed of the Bear River Basin extends from the river's headwaters to Pixley Dam in Wyoming. This is the largest watershed in the Bear River Basin, with an area of about 2,000 square miles.

  1. Predicting hydrological response to forest changes by simple statistical models: the selection of the best indicator of forest changes with a hydrological perspective

    Science.gov (United States)

    Ning, D.; Zhang, M.; Ren, S.; Hou, Y.; Yu, L.; Meng, Z.

    2017-01-01

    Forest plays an important role in hydrological cycle, and forest changes will inevitably affect runoff across multiple spatial scales. The selection of a suitable indicator for forest changes is essential for predicting forest-related hydrological response. This study used the Meijiang River, one of the headwaters of the Poyang Lake as an example to identify the best indicator of forest changes for predicting forest change-induced hydrological responses. Correlation analysis was conducted first to detect the relationships between monthly runoff and its predictive variables including antecedent monthly precipitation and indicators for forest changes (forest coverage, vegetation indices including EVI, NDVI, and NDWI), and by use of the identified predictive variables that were most correlated with monthly runoff, multiple linear regression models were then developed. The model with best performance identified in this study included two independent variables -antecedent monthly precipitation and NDWI. It indicates that NDWI is the best indicator of forest change in hydrological prediction while forest coverage, the most commonly used indicator of forest change is insignificantly related to monthly runoff. This highlights the use of vegetation index such as NDWI to indicate forest changes in hydrological studies. This study will provide us with an efficient way to quantify the hydrological impact of large-scale forest changes in the Meijiang River watershed, which is crucial for downstream water resource management and ecological protection in the Poyang Lake basin.

  2. How does imperviousness develop and affect runoff generation in an urbanizing watershed?

    Directory of Open Access Journals (Sweden)

    Gerald Krebs

    2013-08-01

    Full Text Available Imperviousness associated with urbanization remains one of the biggest challenges in sustainable urban design. The replacement of forests, marshlands, buffers, and wetlands with impervious surfaces, strongly influences hydrological processes in urbanizing areas. This study analyzed the contribution of four constructed surfaces types – roofs, yards, roads, and an international airport – to surface runoff within a 21 km2 watershed, and presents the development over five decades (1977−2030. The land-cover model, used to assess watershed imperviousness in 2030, utilized coefficients between impervious areas generating surface runoff and the floor area, developed during the study. The conducted imperviousness analysis allowed the evaluation of land-use development impacts on the stream network, and the identification of hydrologically active areas for urban planning and stormwater management. Research revealed the importance of yard imperviousness related to suburban residential housing for stormwater runoff generation, and the impacts of transport-related imperviousness on stormwater runoff.

  3. Risk watershed analysis: a new approach to manage torrent control structures

    Science.gov (United States)

    Quefféléan, Yann; Carladous, Simon; Deymier, Christian; Marco, Olivier

    2017-04-01

    Torrential check dams have been built in French public forests since the 19th century, applying the Restoration and conservation of Mountainous Areas (RTM) laws (1860, 1864, 1882). The RTM department of the National Forestry Office (ONF) helps the government to decide on protective actions to implement within these areas. While more than 100 000 structures were registered in 1964, more than 14 000 check dams are currently registered and maintained within approximatively 380 000 ha of RTM public forests. The RTM department officers thus have a long experience in using check dams for soil restoration, but also in implementing other kinds of torrential protective structures such as sediment traps, embankments, bank protection, and so forth. As a part of the ONF, they are also experienced in forestry engineering. Nevertheless, some limits in torrent control management have been highlighted: - as existing protective structures are ageing, their effectiveness to protect elements at risk must be assessed but it is a difficult task ; - as available budget for maintenance is continuously decreasing, priorities have to be made but decisions are difficult : what are the existing check dams functions? what is their expected effect on torrential hazard? is maintenance cost too important given this expected effect to protect elements at risk? Given these questions, a new policy has been engaged by the RTM department since 2012. A technical overview at the torrential watershed scale is now needed to help better maintenance decisions: it has been called a Risk Watershed Analysis (Etude de Bassin de Risque in French, EBR) and is funded by the government. Its objectives are to: - recall initial objectives of protective structures : therefore, a detailed archive analysis is made ; - describe current elements at risk to protect ; - describe natural hazards at the torrential watershed scale and their evolution since protective structures implementation ; - describe civil engineering

  4. Variation of the anthropic vulnerability in Ribeirão das Pedras watershed in Campinas/SP - Brazil.

    Science.gov (United States)

    Damame, Desirée; Longo, Regina; Ribeiro, Admilson; Fengler, Felipe

    2015-04-01

    The human actions has caused over the years profound changes in environmental quality in urban ecosystems suffering losses in the quality of air, soil , water and vegetation also the quality of life of the population that inhabit these areas . The study area is characterized by being a highly urbanized watershed, with about 43 % of its area covered by buildings, houses , and commercial and industrial establishments . Called the Ribeirão das Pedras Basin, located in Campinas / SP - Brazil and is bounded by coordinates 22˚47'10 '' and 22˚52'20 '' S , and 47˚ 07'15 '' and 46˚ 02 ' 15' ' . Has an average temperature of 22.4 ° C and average annual rainfall of 1424.5 mm . It has an area of about 42 km² . This is located two universities and a large mall. It also demands a strong agriculture , which occupies about 30 % of the area . It has also been part of two major forest reserves of the municipality, the Forest Santa Geneva and the Forest of Quilombo , both added to other small fragments overlying only about 6% of the total basin area . Avalição to environmental quality , the analysis of the vulnerability of urban watershed becomes an important environmental management tool. The vulnerability can be defined by susceptibility to changes of environment in its initial state , a current tax status by human intervention , and is almost always associated with risk , and the intensity at which such projects in one place, person or structure. In this context , this study aimed to assess environmental vulnerability in an urban watershed coming under increasing human pressures , especially in recent years . For this analysis were prepared soil graphics, slope , elevation and land use and land cover for the years 2009 and 2014 , generating with these , comparative anthropic vulnerability maps of the past five years. Crafting vulnerability maps is a sensitivity in order to enable appropriate management of biotic systems. With the results can be seen that the variation of

  5. Wind River Watershed Project; 1998 Annual Report; Volume II

    International Nuclear Information System (INIS)

    Connolly, Patrick J.

    1999-01-01

    The authors report here their on-ground restoration actions. Part 1 describes work conducted by the Underwood Conservation District (UCD) on private lands. This work involves the Stabler Cut-Bank project. Part 2 describes work conducted by the U.S. Forest Service. The Stabler Cut-Bank Project is a cooperative stream restoration effort between Bonneville Power Administration (BPA), the UCD, private landowners, the U.S. Forest Service (USFS), and the U.S. Fish and Wildlife Service (USFWS). The Stabler site was identified by UCD during stream surveys conducted in 1996 as part of a USFWS funded project aimed at initiating water quality and habitat restoration efforts on private lands in the basin. In 1997 the Wind River Watershed Council selected the project as a top priority demonstration project. The landowners were approached by the UCD and a partnership developed. Due to their expertise in channel rehabilitation, the Forest Service was consulted for the design and assisted with the implementation of the project. A portion of the initial phase of the project was funded by USFWS. However, the majority of funding (approximately 80%) has been provided by BPA and it is anticipated that additional work that is planned for the site will be conducted with BPA funds

  6. Regional estimation of extreme suspended sediment concentrations using watershed characteristics

    Science.gov (United States)

    Tramblay, Yves; Ouarda, Taha B. M. J.; St-Hilaire, André; Poulin, Jimmy

    2010-01-01

    SummaryThe number of stations monitoring daily suspended sediment concentration (SSC) has been decreasing since the 1980s in North America while suspended sediment is considered as a key variable for water quality. The objective of this study is to test the feasibility of regionalising extreme SSC, i.e. estimating SSC extremes values for ungauged basins. Annual maximum SSC for 72 rivers in Canada and USA were modelled with probability distributions in order to estimate quantiles corresponding to different return periods. Regionalisation techniques, originally developed for flood prediction in ungauged basins, were tested using the climatic, topographic, land cover and soils attributes of the watersheds. Two approaches were compared, using either physiographic characteristics or seasonality of extreme SSC to delineate the regions. Multiple regression models to estimate SSC quantiles as a function of watershed characteristics were built in each region, and compared to a global model including all sites. Regional estimates of SSC quantiles were compared with the local values. Results show that regional estimation of extreme SSC is more efficient than a global regression model including all sites. Groups/regions of stations have been identified, using either the watershed characteristics or the seasonality of occurrence for extreme SSC values providing a method to better describe the extreme events of SSC. The most important variables for predicting extreme SSC are the percentage of clay in the soils, precipitation intensity and forest cover.

  7. Silica uptake and release in live and decaying biomass in a northern hardwood forest.

    Science.gov (United States)

    Clymans, Wim; Conley, Daniel J; Battles, John J; Frings, Patrick J; Koppers, Mary Margaret; Likens, Gene E; Johnson, Chris E

    2016-11-01

    In terrestrial ecosystems, a large portion (20-80%) of the dissolved Si (DSi) in soil solution has passed through vegetation. While the importance of this "terrestrial Si filter" is generally accepted, few data exist on the pools and fluxes of Si in forest vegetation and the rate of release of Si from decomposing plant tissues. We quantified the pools and fluxes of Si through vegetation and coarse woody debris (CWD) in a northern hardwood forest ecosystem (Watershed 6, W6) at the Hubbard Brook Experimental Forest (HBEF) in New Hampshire, USA. Previous work suggested that the decomposition of CWD may have significantly contributed to an excess of DSi reported in stream-waters following experimental deforestation of Watershed 2 (W2) at the HBEF. We found that woody biomass (wood + bark) and foliage account for approximately 65% and 31%, respectively, of the total Si in biomass at the HBEF. During the decay of American beech (Fagus grandifolia) boles, Si loss tracked the whole-bole mass loss, while yellow birch (Betula alleghaniensis) and sugar maple (Acer saccharum) decomposition resulted in a preferential Si retention of up to 30% after 16 yr. A power-law model for the changes in wood and bark Si concentrations during decomposition, in combination with an exponential model for whole-bole mass loss, successfully reproduced Si dynamics in decaying boles. Our data suggest that a minimum of 50% of the DSi annually produced in the soil of a biogeochemical reference watershed (W6) derives from biogenic Si (BSi) dissolution. The major source is fresh litter, whereas only ~2% comes from the decay of CWD. Decay of tree boles could only account for 9% of the excess DSi release observed following the experimental deforestation of W2. Therefore, elevated DSi concentrations after forest disturbance are largely derived from other sources (e.g., dissolution of BSi from forest floor soils and/or mineral weathering). © 2016 The Authors. Ecology, published by Wiley Periodicals

  8. Decreased water flowing from a forest amended with calcium silicate

    Science.gov (United States)

    Mark B. Green; Amey S. Bailey; Scott W. Bailey; John J. Battles; John L. Campbell; Charles T. Driscoll; Timothy J. Fahey; Lucie C. Lepine; Gene E. Likens; Scott V. Ollinger; Paul G. Schaberg

    2013-01-01

    Acid deposition during the 20th century caused widespread depletion of available soil calcium (Ca) throughout much of the industrialized world. To better understand how forest ecosystems respond to changes in a component of acidification stress, an 11.8-ha watershed was amended with wollastonite, a calcium silicate mineral, to restore available soil Ca to preindustrial...

  9. An annotated list of the flora of the Bisley Area Luquillo Experimental Forest, Puerto Rico 1987 to 1992

    Science.gov (United States)

    Jesus Danilo Chinea; Renee J. Beymer; Carlos Rivera; Ines Sastre de Jeses; F.N. Scatena

    1993-01-01

    Known species of plants, including bryophytes and ferns, are listed for the area of the Bisley experimental watershed area, a subtropical wet forest in the Luquillo Mountains of northeastern Puerto Rico.

  10. Rangeland degradation in two watersheds of Lebanon

    International Nuclear Information System (INIS)

    Darwish, T; Faour, G.

    2008-01-01

    A complex and rugged nature characterizes the Lebanese mountains.The climatic pattern prevailing in the country, deforestation and man made erosion caused increased rangeland degradation. The purpose of this study was to monitor two contrasting watersheds, representing the Lebanese agro-ecological zones, to analyze the vegetation dynamics and trace the state of rangeland degradation. The Kfarselouane (205 km2) and Aarsal (316.7 km2) watersheds are located in the Lebanon and Anti-Lebanon mountain chain and characterized by sub humid and semi-arid climate respectively.Using multitemporal spot vegetation images between 1999 and 2005 to analyze the normalized differential vegetation index (NDVI) revealed some improvement of the vegetation cover over recent years in Kfaselouane with a steady state in Aarsal. The NDVI trend curve inclines in spring and declines in summer and fall. Judging by the time scale amplitude change and highest magnitude between the peak and lower NDVI level in Aarsal, an increased vulnerability to drought is observed in the dry Lebanese areas. Comparing land cover/use in Aarsal area between 1962 and 2000 using aerial photos and large resolution Indian satellite images (IRS) showed wood fragmentation and slight increase of the degenerated forest cover from 1108 ha to 1168 ha. Landuse change was accompanied by a simultaneous increase of cultivated lands (mostly fruit trees) from 932 ha to 4878 ha with absence of soil conservation and water harvesting practices. On the contrary, grasslands decreased from 29581 ha to 25000 ha. In Kfarselouane, the area of grassland was invaded by forestland where rangeland decreased from 8073 ha to 3568 ha and woodland increased from 5766 ha to 11800 ha. Forest expansion occurred even at the account of unproductive land which decreased from 2668 ha to 248 ha, while cultivated lands did not reveal any substantial change. Based on animals' seasonal feeding pattern, a mismatch between land carrying capacity and grazing

  11. Options for biodiversity conservation in managed forest landscapes of multiple ownerships in Oregon and Washington, USA.

    Science.gov (United States)

    N. Suzuki; D.H. Olson

    2007-01-01

    We review the policies and management approaches used in U.S. Pacific Northwest planted forest to address biodiversity protection. We provide a case-study watershed design from southern Oregon, integrating various stand-to-landscape biodiversity-management approaches.

  12. Comparison of methods for determining the hydrologic recovery time after forest disturbance

    Science.gov (United States)

    Oda, T.; Green, M.; Ohte, N.; Urakawa, R.; Endo, I.; Scanlon, T. M.; Sebestyen, S. D.; McGuire, K. J.; Katsuyama, M.; Fukuzawa, K.; Tague, C.; Hiraoka, M.; Fukushima, K.; Giambelluca, T. W.

    2013-12-01

    Changes in forest hydrology changes after forest disturbance vary among catchments. Although studies have summarized the initial runoff changes following forest disturbance, the estimates of long-term recovery time are less frequently reported. To understand the mechanisms of long-term recovery processes and to predict the long-term changes in streamflow after forest disturbance, it is important to compare recovery times after disturbance. However, there is no clear consensus regarding the best methodology for such research, especially for watershed studies that were not designed as paired watersheds. We compared methods of determining the hydrologic recovery time to determine if there is a common method for sites in any hydroclimatic setting. We defined the hydrologic recovery time to be the time of disturbance to the time when hydrological factors first recovered to pre-disturbance levels. We acquired data on long-term rainfall and runoff at 16 sites in northeastern USA and Japan that had at least 10 years (and up to 50 years) of post disturbance data. The types of disturbance include harvesting, diseases and insect damages. We compared multiple indices of hydrological response including annual runoff, annual runoff ratio (annual runoff/annual rainfall), annual loss (annual rainfall-annual runoff), fiftieth-percentile annual flow, and seasonal water balance. The results showed that comparing annual runoff to a reference site was most robust at constraining the recovery time, followed by using pre-disturbance data as reference data and calculating the differences in annual runoff from pre-disturbance levels. However, in case of small disturbance at sites without reference data or long-term pre-disturbance data, the inter-annual variation of rainfall makes the effect of disturbance unclear. We found that annual loss had smaller inter-annual variation, and defining recovery time with annual loss was best in terms of matching the results from paired watersheds. The

  13. Assessment of the fate of anthropogenic nitrogen in large watersheds by isotopic techniques

    International Nuclear Information System (INIS)

    Mayer, B.

    1999-01-01

    Human activity has greatly altered the nitrogen cycle in terrestrial and aquatic ecosystems and increased the nitrogen flow in many rivers. Preliminary work of the International SCOPE Nitrogen Project indicates that only 20% of the human-controlled nitrogen inputs to large watersheds are exported to the oceans in riverine flow (Howarth, 1998). Therefore, approximately 80% of the anthropogenic nitrogen inputs are either stored or denitrified in the catchments. Anthropogenic nitrogen can be retained in forests (possibly as a result of increased productivity) or in agricultural soils. It can also be stored in groundwater. These sinks are, however, often not large enough to account for the 'missing' nitrogen. It is, therefore, assumed that the majority of the human-controlled nitrogen inputs to large watersheds is denitrified in soils, riparian zones, wetlands, lakes, and rivers. Within the SCOPE Nitrogen Project, preliminary isotope analyses were performed on dissolved nitrates from several streams draining into the North Atlantic Ocean. Both δ 15 N nitrate and δ 18 O nitrate values were determined in order to identify nitrate sources. A further objective was to test, whether the isotopic composition of dissolved nitrate provides a measure for the extent to which denitrification occurs in the respective watersheds

  14. Soil carbon storage estimation in a forested watershed using quantitative soil-landscape modeling

    Science.gov (United States)

    James A. Thompson; Randall K. Kolka

    2005-01-01

    Carbon storage in soils is important to forest ecosystems. Moreover, forest soils may serve as important C sinks for ameliorating excess atmospheric CO2. Spatial estimates of soil organic C (SOC) storage have traditionally relied upon soil survey maps and laboratory characterization data. This approach does not account for inherent variability...

  15. Impact of Land Use on the Mobility of Hg Species in Different Compartments of a Tropical Watershed in Brazil.

    Science.gov (United States)

    de Lima, Clara Ayume Ito; de Almeida, Marcelo Gomes; Pestana, Inacio Abreu; Bastos, Wanderley R; do Nascimento Recktenvald, Maria Cristina Nery; de Souza, Cristina Maria Magalhães; Pedrosa, Paulo

    2017-11-01

    This study evaluated the levels of total Hg and CH 3 Hg + from a comprehensive perspective, considering the retention, leaching, and deposition of these contaminants in the main compartments (soil, plant litter, and sediment) of three landscapes (Atlantic Forest, pasture, and agricultural area) in a watershed in northern Rio de Janeiro State, Brazil. Variables analyzed were total Hg, CH 3 Hg + , organic carbon, total nitrogen, grain size, and surface area. In soil samples, total Hg levels were the highest in agricultural soil followed by forest soil and pasture (97.3, 87.6, and 77.1 ng g -1 , respectively), and CH 3 Hg + was lower than 1.7%. Total Hg levels in leaf litter varied between 22.6 and 34.2 ng g -1 , and CH 3 Hg + was 4.37%. In sediment, Hg (60-180 ng g -1 ) and CH 3 Hg + (Hg species, and the effect of each variable varied with the landscape, showing that plant cover should not be ignored in investigations related to Hg species retention in a watershed. The landscapes surveyed in the present study clearly influence the quantitative and qualitative distribution of Hg species. On the other hand, anthropic processes associated with changes in soil use did not have any critical effects on the absolute levels of total Hg and CH 3 Hg + , meaning that the landscapes evaluated seem to represent the background concentration of these chemical species for the evaluated watershed.

  16. Theoretical Study of Watershed Eco-Compensation Standards

    Science.gov (United States)

    Yan, Dandan; Fu, Yicheng; Liu, Biu; Sha, Jinxia

    2018-01-01

    Watershed eco-compensation is an effective way to solve conflicts over water allocation and ecological destruction problems in the exploitation of water resources. Despite an increasing interest in the topic, the researches has neglected the effect of water quality and lacked systematic calculation method. In this study we reviewed and analyzed the current literature and proposedatheoretical framework to improve the calculation of co-compensation standard.Considering the perspectives of the river ecosystems, forest ecosystems and wetland ecosystems, the benefit compensation standard was determined by the input-output corresponding relationship. Based on the opportunity costs related to limiting development and water conservation loss, the eco-compensation standard was calculated.In order to eliminate the defects of eco-compensation implementation, the improvement suggestions were proposed for the compensation standard calculation and implementation.

  17. Yesterday's forest, tomorrow's savannah? Legacies in the man-made hills of Appalachia

    Science.gov (United States)

    Ross, M. R. V.; Nippgen, F.; McGlynn, B. L.; Bernhardt, E. S.

    2017-12-01

    Mountaintop removal coal mines have converted more than 6,000 km2 of the steep forested valleys of Central Appalachian into a landscape of rolling hills covered by shrubby grasslands. These landscapes were created as a byproduct of extracting shallow coal seams from beneath hundreds of meters of overlying bedrock. Once broken apart by explosives, this excess rock overburden is deposited into valley fills and incorporated into reconstructed ridges. The landscapes left behind after mining are flattened and overlies highly fractured fill material that can be 100-fold deeper than natural soil. This fractured bedrock material can store 2-10 years worth of average precipitation, where any stored water is in contact with a reactive mix of unweathered carbonate bedrock and pyrite rich coal and shale residues. As a result, mountaintop mined watersheds have novel hydrologic and biogeochemical regimes with increases in baseflow and extremely rapid weathering that increases salinity by 10-25-fold. To date, little research has characterized the longevity of these impacts. We employed a combination of remote sensing and hydrologic watershed monitoring approaches to examine the long-term and linked changes in vegetation, hydrology, and water quality in a post-mine landscapes that were constructed between 1990 and 2016. We find that forest recovery on mountaintop mines progresses at half the rate of forest regrowth following clearcutting with persistent low canopy-height sections, consistent more with grasslands than forests. These vegetative changes are associated with decreases in runoff ratios as mines age and water moves through flatter, vegetated landscapes. However, vegetation change appears to be uncoupled from biogeochemical processes, with saline mine drainage persisting for decades, even as vegetation regrows. Our work suggests that time-since-mining of a watershed does not predict downstream water quality, while total valley fill volume remains a strong predictor of

  18. Wet and Dry Atmospheric Mercury Deposition Accumulates in Watersheds of the Northeastern United States

    Science.gov (United States)

    Boyer, E. W.; Grant, C.; Grimm, J.; Drohan, P. J.; Bennett, J.; Lawler, D.

    2013-12-01

    Mercury emissions to the atmosphere from coal-fired power plants and other sources such as waste incineration can be deposited to landscapes in precipitation and in dry fallout. Some mercury reaches watersheds and streams, where it can accumulate in sediments and biota. Human exposure to mercury occurs primarily through fish consumption, and currently mercury fish eating advisories are in place for many of the streams and lakes in the state. Here, we explored mercury in air, soils, water, and biota. To quantify atmospheric mercury deposition, we measured both wet and dry mercury deposition at over 10 locations in Pennsylvania, from which we present variation in mercury deposition and initial assessments of factors affecting the patterns. Further, we simulated mercury deposition at unmonitored locations in Pennsylvania and the northeastern United States over space and time with a high-resolution modeling technique that reflects storm tracks and air flow patterns. To consider mercury accumulation in watersheds, we collected data on soil mercury concentrations in a set of soil samples, and collected baseline data on mercury in streams draining 35 forested watersheds across Pennsylvania, spanning gradients of atmospheric deposition, climate and geology. Mercury concentrations were measured in stream water under base-flow conditions, in streambed sediments, aquatic mosses, and in fish tissues from brook trout. Results indicate that wet and dry atmospheric deposition is a primary source of mercury that is accumulating in watersheds of Pennsylvania and the northeastern United States.

  19. Retrospective Review of Watershed Characteristics and a Framework for Future Research in the Sarasota Bay Watershed, Florida

    Science.gov (United States)

    Kish, George R.; Harrison, Arnell S.; Alderson, Mark

    2008-01-01

    The U.S. Geological Survey, in cooperation with the Sarasota Bay Estuary Program conducted a retrospective review of characteristics of the Sarasota Bay watershed in west-central Florida. This report describes watershed characteristics, surface- and ground-water processes, and the environmental setting of the Sarasota Bay watershed. Population growth during the last 50 years is transforming the Sarasota Bay watershed from rural and agriculture to urban and suburban. The transition has resulted in land-use changes that influence surface- and ground-water processes in the watershed. Increased impervious cover decreases recharge to ground water and increases overland runoff and the pollutants carried in the runoff. Soil compaction resulting from agriculture, construction, and recreation activities also decreases recharge to ground water. Conventional approaches to stormwater runoff have involved conveyances and large storage areas. Low-impact development approaches, designed to provide recharge near the precipitation point-of-contact, are being used increasingly in the watershed. Simple pollutant loading models applied to the Sarasota Bay watershed have focused on large-scale processes and pollutant loads determined from empirical values and mean event concentrations. Complex watershed models and more intensive data-collection programs can provide the level of information needed to quantify (1) the effects of lot-scale land practices on runoff, storage, and ground-water recharge, (2) dry and wet season flux of nutrients through atmospheric deposition, (3) changes in partitioning of water and contaminants as urbanization alters predevelopment rainfall-runoff relations, and (4) linkages between watershed models and lot-scale models to evaluate the effect of small-scale changes over the entire Sarasota Bay watershed. As urbanization in the Sarasota Bay watershed continues, focused research on water-resources issues can provide information needed by water

  20. Human uses of forested watersheds and riparian corridors: hazard mitigation as an ecosystem service, with examples from Panama, Puerto Rico, and Venezuela

    Science.gov (United States)

    Larsen, M. C.

    2015-12-01

    Humans have long favored settlement along rivers for access to water supply for drinking and agriculture, for transport corridors, and for food sources. Additionally, settlement in or near montane forests include benefits such as food sources, wood supply, esthetic values, and high quality water resources derived from watersheds where upstream human disturbance and environmental degradation is generally reduced. However, the advantages afforded by these riparian and montane settings pose episodic risks for communities located there as floods, landslides, and wildfires cause loss of life, destroy infrastructure, and damage or destroy crops. A basic understanding of flood probability and magnitude as well as hillslope stability by residents in these environments can mitigate these risks. Early humans presumably developed some degree of knowledge about these risks by means of their long periods of occupation in these environments and their observations of seasonal and storm rainfall patterns and river discharge, which became more refined as agriculture developed over the past 10,000 years. Modern global urbanization, particularly in regions of rapid economic growth, has resulted in much of this "organic" knowledge being lost, as rural populations move into megacities, many of which encroach on floodplains and mountain fronts. Moreover, the most likely occupants of these hazardous locations are often economically constrained, increasing their vulnerabity. Effective stewardship of river floodplains and upstream montane forests yields a key ecosystem service, which in addition to the well-known services, ie. water, hydroelectric energy, etc., provides a risk mitigation service, by reducing hazard and vulnerability. Puerto Rico, Panama, and Venezuela illustrate a range of practices and results, providing useful examples for planners and land use managers.

  1. Can Runoff Responses be Used to Predict Aquatic Biogeochemical Fluxes from Boreal Forest Ecosystems?

    Science.gov (United States)

    Prestegaard, K. L.; Ziegler, S. E.; Billings, S. A.; Edwards, K. A.

    2017-12-01

    Climate change has direct effects on precipitation and temperature, which contribute to indirect changes in ecosystem productivity, runoff, biogeochemical processes, and species composition. In this research, we examine water balances in boreal forest watersheds to determine spatial and inter-annual variations in their responses to changes in precipitation. Our research indicates that Central and Western N. American boreal watersheds with mean annual precipitation (MAP) of less than 1000 mm exhibit positive relationships between annual precipitation and annual evapotranspiration, suggesting an increase in forest productivity during wet years often without increased runoff. In Maritime boreal watersheds in Eastern N. America and N. Europe, runoff is a significantly larger portion of the water balance and runoff increases with precipitation This regionalism in the water balance may have significant consequences for biogeochemical fluxes; for example, where MAP >1000 mm, a future wetter climate may result in increases in the terrestrial-to-aquatic transport of solutes. To test this idea, we examined inter-annual variations in hydrologic and dissolved organic carbon fluxes in watersheds in Newfoundland and Labrador along a longitudinal transect. Mean annual temperature varies from 0-5.2oC along the transect, and MAP varies from 1050 to 1500 mm. Data indicate an increase in evapotranspiration, runoff, and soil DOC fluxes with the increasing mean annual precipitation among watersheds along the transect. During the 2011-2015 period of study there was significant overlap in annual precipitation among the sites. Although wet water years also produced higher amounts of runoff from most watersheds, the annual soil DOC flux within each region was not significantly affected by these inter-annual changes in precipitation. Stream and groundwater monitoring data from the catchments reveal seasonal variations in evapotranspiration and runoff and their role in solute fluxes, and

  2. Effects of Nitrogen Enrichment, Wildfire, and Harvesting on Forest-Soil Carbon and Nitrogen

    Science.gov (United States)

    Jennifer L. Parker; Ivan J. Fernandez; Lindsey E. Rustad; Stephen A. Norton

    2001-01-01

    Northern forest soils represent large reservoirs of C and N that may be altered by ecosystem perturbations. Soils at three paired watershed in Maine were investigated as case studies of experimentally elevated N deposition, wildfire, and whole-tree harvesting. Eight years of experimental (NH4)2SO4...

  3. DETECTING FOREST STRESS AND DECLINE IN RESPONSE TO INCREASING RIVER FLOW IN SOUTHWEST FLORIDA, USA

    Science.gov (United States)

    Forest stress and decline resulting from increased river flows were investigated in Myakka River State Park (MRSP), Florida, USA. Since 1977, land-use changes around the upper Myakka River watershed have resulted in significant increases in water entering the river, which have...

  4. The Northern hardwood forest ecosystem: ten years of recovery from clearcutting

    Science.gov (United States)

    J.W. Hornbeck; C.W. Martin; R.S. Pierce; F.H. Bormann; G.E. Likens; J.S. Eaton; J.S. Eaton

    1987-01-01

    Two even-age management systems, progressive strip cutting and block clearcutting, have been studied since 1970 on small watersheds at the Hubbard Brook Experimental Forest, New Hampshire. In the strip cutting, all merchantable trees were harvested in a series of three strips over 4 years (1970-74). In the block clearcutting, all trees were harvested in a single...

  5. THE BEAR BROOK WATERSHED MANIPULATION PROJECT: WATERSHED SCIENCE IN A POLICY PERSPECTIVE

    Science.gov (United States)

    The Bear Brook Watershed Manipulation in Maine is a paired watershed experiment. Monitoring of the paired catchments (East Bear Brook - reference; West Bear Brook - experimental) began in early 1987. Chemical manipulation of West Bear Brook catchment began in November 1989. Proce...

  6. Longer-term Stream Nitrogen Dynamics after Wildfire and Salvage Harvesting: Implications for Management Concepts based on Trajectories of Post-disturbance Watershed Recovery.

    Science.gov (United States)

    Silins, U.; Emelko, M. B.; Bladon, K. D.; Stone, M.; Williams, C.; Martens, A. M.; Wagner, M. J.

    2015-12-01

    Biogeochemical processes reflecting interaction of vegetation and hydrology govern long-term export of nutrients such as nitrogen, phosphorus, and carbon over successional time scales. While management concepts of watershed "recovery" from disturbance back towards pre-disturbance conditions are often considered over much shorter timescales, few studies have directly explored watershed biogeochemical responses to disturbance long enough to directly document the longer-term trajectory of responses to severe land disturbance on nitrogen export. The objectives of this study were to document both the initial magnitude and patterns of longer-term recovery of stream nitrogen after the 2003 Lost Creek wildfire over nine years in front ranges of the Rocky Mountains in south-west Alberta, Canada. The study was conducted in seven instrumented catchments (4-14 km2), including burned, burned and salvage logged, and unburned (reference) conditions since 2004. Total nitrogen (TN) and nitrate (NO3-) concentrations and area-normalized yields were greater and more variable in burned and post-fire salvage logged catchments when compared with unburned catchments. Large initial increases in stream TN and NO3- production 1-3 years after both wildfire and post-fire salvage logging declined strongly to levels similar to, or below that of unburned watersheds 4-6 years after the fire, and continued to decline (although more slowly) 7-9 years after the wildfire. Post-fire salvage logging produced lower impacts on TN and NO3- in streams and these effects declined even more rapidly compared to the effects of wildfire alone. These changes closely corresponded to the early trajectory of establishment and rapid juvenile growth of post-fire regenerating forest vegetation in both catchment groups. While the concept of hydrologic recovery from disturbance is both a practical and meaningful concept for integrated landscape management for protection of forest water resources, the benchmark for

  7. Using a Forest Health Index as an Outreach Tool for Improving Public Understanding of Ecosystem Dynamics and Research-Based Management

    Science.gov (United States)

    Osenga, E. C.; Cundiff, J.; Arnott, J. C.; Katzenberger, J.; Taylor, J. R.; Jack-Scott, E.

    2015-12-01

    An interactive tool called the Forest Health Index (FHI) has been developed for the Roaring Fork watershed of Colorado, with the purpose of improving public understanding of local forest management and ecosystem dynamics. The watershed contains large areas of White River National Forest, which plays a significant role in the local economy, particularly for recreation and tourism. Local interest in healthy forests is therefore strong, but public understanding of forest ecosystems is often simplified. This can pose challenges for land managers and researchers seeking a scientifically informed approach to forest restoration, management, and planning. Now in its second iteration, the FHI is a tool designed to help bridge that gap. The FHI uses a suite of indicators to create a numeric rating of forest functionality and change, based on the desired forest state in relation to four categories: Ecological Integrity, Public Health and Safety, Ecosystem Services, and Sustainable Use and Management. The rating is based on data derived from several sources including local weather stations, stream gauge data, SNOTEL sites, and National Forest Service archives. In addition to offering local outreach and education, this project offers broader insight into effective communication methods, as well as into the challenges of using quantitative analysis to rate ecosystem health. Goals of the FHI include its use in schools as a means of using local data and place-based learning to teach basic math and science concepts, improved public understanding of ecological complexity and need for ongoing forest management, and, in the future, its use as a model for outreach tools in other forested communities in the Intermountain West.

  8. Monitoring the Impacts of Forest Management on Snowpack Duration

    Science.gov (United States)

    O'Halloran, T.; Tyler, S.; Gaffney, R.; Pai, H.

    2017-12-01

    Seasonal snowpack constitutes a significant portion of the hydrologic budget in mountain watersheds and influences dynamic (e.g., runoff magnitude and timing, soil moisture availability) and energetic processes (e.g., surface-atmosphere energy fluxes, ground temperature). Altered forest structure can affect snow accumulation and ablation. As part of a long-term monitoring project, this work examines the impact of forest management practices on snow cover in Lassen National Forest, California. We deployed a fiber optic distributed temperature sensing (DTS) cable and multiple meteorological stations in thinned, clear-cut, and untreated areas of forest. The DTS data was collected at 1 meter spatial intervals every 4 hours from February to May 2017. To determine snow cover, daily temperature variations were examined along locations of the DTS cable associated with our areas of interest. Between the various treatments, snow duration was greater in both clear-cut and untreated forest compared to the thinned area. However, snow duration varied by only six days. We also investigated other meteorological forcings, such as average winter temperature and precipitation, which coupled with forest modifications could explain snow duration in our study.

  9. Effects of land use and management on aggregate stability and hydraulic conductivity of soils within River Njoro Watershed in Kenya

    Directory of Open Access Journals (Sweden)

    Zachary G. Mainuri

    2013-09-01

    Full Text Available There has been tremendous changes in land use and management in the River Njoro Watershed during the last three decades. Formerly large scale farms have been converted into smallholder farms and plantation forests have gradually been lost. These changes in land use and management have brought in different approaches that have triggered soil erosion and other forms of land degradation. The objective of this study was to trace the changes in land use and determine their effects on aggregate stability and hydraulic conductivity. A semi detailed soil survey of the watershed was undertaken following a three-tier approach comprising image interpretation, field surveys and laboratory analysis. The measured variables in the soil were analysed using ANOVA and correlation analysis. The major land uses were found to be forestland, agricultural land, grassland, and wetland. A strong soil type _ landscape relationship was observed within the watershed. Soils of slopes were moderately to severely eroded, shallow and less developed whereas those on summits, pen plains, uplands, plateaus and valleys were deep and well developed. Aggregate stability was the highest in forestland and decreased in the order of grassland, agricultural land and wetland respectively. The mean weight diameter under the various land use conditions was 0.68, 0.64, 0.58, and 0 41 respectively. Hydraulic conductivity was the highest in forest-land and decreased in the order of agricultural land, grassland and wetland respectively. There was significant negative correlation between hydraulic conductivity and the bulk density and clay content of the soils. Reduced aggregate stability and lowered hydraulic conductivity is likely to be responsible for some of the severe soil erosion and other forms of land degradation observed in the River Njoro Watershed.

  10. EnviroAtlas - Number of Water Markets per HUC8 Watershed, U.S., 2015, Forest Trends' Ecosystem Marketplace

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset contains polygons depicting the number of watershed-level market-based programs, referred to herein as markets, in operation per 8-digit HUC...

  11. 75 FR 11837 - Chesapeake Bay Watershed Initiative

    Science.gov (United States)

    2010-03-12

    ... DEPARTMENT OF AGRICULTURE Commodity Credit Corporation Chesapeake Bay Watershed Initiative AGENCY...: Notice of availability of program funds for the Chesapeake Bay Watershed Initiative. SUMMARY: The... through the Chesapeake Bay Watershed Initiative for agricultural producers in the Chesapeake Bay watershed...

  12. Biogeochemical impacts of wildfires over four millennia in a Rocky Mountain subalpine watershed.

    Science.gov (United States)

    Dunnette, Paul V; Higuera, Philip E; McLauchlan, Kendra K; Derr, Kelly M; Briles, Christy E; Keefe, Margaret H

    2014-08-01

    Wildfires can significantly alter forest carbon (C) storage and nitrogen (N) availability, but the long-term biogeochemical legacy of wildfires is poorly understood. We obtained a lake-sediment record of fire and biogeochemistry from a subalpine forest in Colorado, USA, to examine the nature, magnitude, and duration of decadal-scale, fire-induced ecosystem change over the past c. 4250 yr. The high-resolution record contained 34 fires, including 13 high-severity events within the watershed. High-severity fires were followed by increased sedimentary N stable isotope ratios (δ15N) and bulk density, and decreased C and N concentrations--reflecting forest floor destruction, terrestrial C and N losses, and erosion. Sustained low sediment C : N c. 20-50 yr post-fire indicates reduced terrestrial organic matter subsidies to the lake. Low sedimentary δ15N c. 50-70 yr post-fire, coincident with C and N recovery, suggests diminishing terrestrial N availability during stand development. The magnitude of post-fire changes generally scaled directly with inferred fire severity. Our results support modern studies of forest successional C and N accumulation and indicate pronounced, long-lasting biogeochemical impacts of wildfires in subalpine forests. However, even repeated high-severity fires over millennia probably did not deplete C or N stocks, because centuries between high-severity fires allowed for sufficient biomass recovery. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  13. Assessing the effects of regional payment for watershed services program on water quality using an intervention analysis model.

    Science.gov (United States)

    Lu, Yan; He, Tian

    2014-09-15

    Much attention has been recently paid to ex-post assessments of socioeconomic and environmental benefits of payment for ecosystem services (PES) programs on poverty reduction, water quality, and forest protection. To evaluate the effects of a regional PES program on water quality, we selected chemical oxygen demand (COD) and ammonia-nitrogen (NH3-N) as indicators of water quality. Statistical methods and an intervention analysis model were employed to assess whether the PES program produced substantial changes in water quality at 10 water-quality sampling stations in the Shaying River watershed, China during 2006-2011. Statistical results from paired-sample t-tests and box plots of COD and NH3-N concentrations at the 10 stations showed that the PES program has played a positive role in improving water quality and reducing trans-boundary water pollution in the Shaying River watershed. Using the intervention analysis model, we quantitatively evaluated the effects of the intervention policy, i.e., the watershed PES program, on water quality at the 10 stations. The results suggest that this method could be used to assess the environmental benefits of watershed or water-related PES programs, such as improvements in water quality, seasonal flow regulation, erosion and sedimentation, and aquatic habitat. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Assessing Anthropogenic Influence and Edge Effect Influence on Forested Riparian Buffer Spatial Configuration and Structure: An Example Using Lidar Remote Sensing Methods

    Science.gov (United States)

    Wasser, L. A.; Chasmer, L. E.

    2012-12-01

    Forested riparian buffers (FRB) perform numerous critical ecosystem services. However, globally, FRB spatial configuration and structure have been modified by anthropogenic development resulting in widespread ecological degradation as seen in the Gulf of Mexico and the Chesapeake Bay. Riparian corridors within developed areas are particularly vulnerable to disturbance given two edges - the naturally occurring stream edge and the matrix edge. Increased edge length predisposes riparian vegetation to "edge effects", characterized by modified physical and environmental conditions at the interface between the forested buffer and the adjacent landuse, or matrix and forest fragment degradation. The magnitude and distance of edge influence may be further influenced by adjacent landuse type and the width of the buffer corridor at any given location. There is a need to quantify riparian buffer spatial configuration and structure over broad geographic extents and within multiple riparian systems in support of ecologically sound management and landuse decisions. This study thus assesses the influence of varying landuse types (agriculture, suburban development and undeveloped) on forested riparian buffer 3-dimensional structure and spatial configuration using high resolution Light Detection and Ranging (LiDAR) data collected within a headwater watershed. Few studies have assessed riparian buffer structure and width contiguously for an entire watershed, an integral component of watershed planning and restoration efforts such as those conducted throughout the Chesapeake Bay. The objectives of the study are to 1) quantify differences in vegetation structure at the stream and matrix influenced riparian buffer edges, compared to the forested interior and 2) assess continuous patterns of changes in vegetation structure throughout the buffer corridor beginning at the matrix edge and ending at the stream within buffers a) of varying width and b) that are adjacent to varying landuse

  15. Restoring Forests and Associated Ecosystem Services on Appalachian Coal Surface Mines

    Science.gov (United States)

    Zipper, Carl E.; Burger, James A.; Skousen, Jeffrey G.; Angel, Patrick N.; Barton, Christopher D.; Davis, Victor; Franklin, Jennifer A.

    2011-05-01

    Surface coal mining in Appalachia has caused extensive replacement of forest with non-forested land cover, much of which is unmanaged and unproductive. Although forested ecosystems are valued by society for both marketable products and ecosystem services, forests have not been restored on most Appalachian mined lands because traditional reclamation practices, encouraged by regulatory policies, created conditions poorly suited for reforestation. Reclamation scientists have studied productive forests growing on older mine sites, established forest vegetation experimentally on recent mines, and identified mine reclamation practices that encourage forest vegetation re-establishment. Based on these findings, they developed a Forestry Reclamation Approach (FRA) that can be employed by coal mining firms to restore forest vegetation. Scientists and mine regulators, working collaboratively, have communicated the FRA to the coal industry and to regulatory enforcement personnel. Today, the FRA is used routinely by many coal mining firms, and thousands of mined hectares have been reclaimed to restore productive mine soils and planted with native forest trees. Reclamation of coal mines using the FRA is expected to restore these lands' capabilities to provide forest-based ecosystem services, such as wood production, atmospheric carbon sequestration, wildlife habitat, watershed protection, and water quality protection to a greater extent than conventional reclamation practices.

  16. 77 FR 33390 - Beaverhead-Deerlodge National Forest; Montana; Supplemental EIS for the Beaverhead-Deerlodge...

    Science.gov (United States)

    2012-06-06

    ..., watershed, vegetation, wildlife, and recreation users. This analysis will be used to determine if snowmobile... Land and Resource Management Plan (Forest Plan) environmental analysis in response to an April 2, 2012.... District Court for the District of Montana (Case 9:10-cv-00104-DWM) alleging inadequate analysis of the...

  17. Hydrologic characteristics of benchmark soils of Hawaii’s forest watersheds-

    Science.gov (United States)

    L. R. Ahuja; S. A. El-Swaify

    1975-01-01

    The project was initiated in May, 1972. the initial effort involved mapping of forest soils on the islands of Oahu and Kawaii, and collection of relevant literature for preparing the study plan. The detailed study plan (el-Swaify, 1972) was prepared after cooperative discussions with staff of the Institute of Pacific Islands Forestry, Honolulu, Hawaii, and set forth...

  18. Adaptive Management Fitness of Watersheds

    Directory of Open Access Journals (Sweden)

    Ignacio Porzecanski

    2012-09-01

    Full Text Available Adaptive management (AM promises to improve our ability to cope with the inherent uncertainties of managing complex dynamic systems such as watersheds. However, despite the increasing adherence and attempts at implementation, the AM approach is rarely successful in practice. A one-size-fits-all AM strategy fails because some watersheds are better positioned at the outset to succeed at AM than others. We introduce a diagnostic tool called the Index of Management Condition (IMC and apply it to twelve diverse watersheds in order to determine their AM "fitness"; that is, the degree to which favorable adaptive management conditions are in place in a watershed.

  19. Meaningful Watershed Experiences for Middle and High School Students

    Science.gov (United States)

    Landry, Melinda; Smith, Cynthia; Greene, Joy

    2014-05-01

    Prince William County Public Schools and George Mason University in Virginia, USA, partnered to provide Meaningful Watershed Educational Experiences (MWEEs) for over 25,000 middle and high school students (11-18 year olds) across 34 schools. This school district, situated in a rapidly growing region 55 km southwest of Washington DC, has over 82,000 K-12 students. As native forest cover has been replaced with farming and urbanization, water quality has significantly degraded in the 166,534 km2 Chesapeake Bay watershed. This project was designed to increase student awareness of their impact on the land and waters of the largest estuary in the United States. MWEE is a long-term comprehensive project that incorporates a classroom preparation phase, a hands-on outdoor field investigation, and a reflection and data-sharing component. Training and technical assistance enhances the capacity of teachers of 6th grade, high school Earth Science and Environmental Science to deliver MWEEs which includes schoolyard stewardship, inquiry driven field study, use of hand-held technology and computer based mapping and analysis, project sharing and outreach. George Mason University researchers worked closely with K-12 science educators to create a comprehensive watershed-focused curriculum. Graduate and undergraduate students with strong interests in environmental science and education were trained to deliver the field investigation component of the MWEE. Representative teachers from each school were provided 3 days of professional development and were responsible for the training of their school's science education team. A comprehensive curriculum provided teachers with activities and tools designed to enhance students' mastery of state science objectives. Watershed concepts were used as the unifying theme to support student understanding of curriculum and STEM objectives including: scientific investigation, data collection and communication, chemistry, energy, erosion, human

  20. A Watershed Integrity Definition and Assessment Approach to Support Strategic Management of Watersheds

    Science.gov (United States)

    Although defined hydrologically as a drainage basin, watersheds are systems that physically link the individual social and ecological attributes that comprise them. Hence the structure, function, and feedback systems of watersheds are dependent on interactions between these soci...

  1. Cover Crops for Managing Stream Water Quantity and Improving Stream Water Quality of Non-Tile Drained Paired Watersheds

    Directory of Open Access Journals (Sweden)

    Gurbir Singh

    2018-04-01

    Full Text Available In the Midwestern United States, cover crops are being promoted as a best management practice for managing nutrient and sediment losses from agricultural fields through surface and subsurface water movement. To date, the water quality benefits of cover crops have been inferred primarily from plot scale studies. This project is one of the first to analyze the impacts of cover crops on stream water quality at the watershed scale. The objective of this research was to evaluate nitrogen, phosphorus, and sediment loss in stream water from a no-till corn-soybean rotation planted with winter cover crops cereal rye (Secale cereale and hairy vetch (Vicia villosa in non-tile drained paired watersheds in Illinois, USA. The paired watersheds are under mixed land use (agriculture, forest, and pasture. The control watershed had 27 ha of row-crop agriculture, and the treatment watershed had 42 ha of row crop agriculture with cover crop treatment (CC-treatment. During a 4-year calibration period, 42 storm events were collected and Event Mean Concentrations (EMCs for each storm event were calculated for total suspended solids (TSS, nitrate-N (NO3-N, ammonia-N (NH4-N, dissolved reactive phosphorus (DRP, and total discharge. Predictive regression equations developed from the calibration period were used for calculating TSS, NO3-N, NH4-N, and DRP losses of surface runoff for the CC-treatment watershed. The treatment period consisted of total 18 storm events, seven of which were collected during the cereal rye, eight in the hairy vetch cover crop season and three during cash crop season. Cover crops reduced TSS and discharge by 33% and 34%, respectively in the CC-treatment watershed during the treatment period. However, surprisingly, EMCs for NO3-N, NH4-N, and DRP did not decrease. Stream discharge from the paired-watersheds will continue to be monitored to determine if the current water quality results hold or new patterns emerge.

  2. Forest nutrient and carbon pools at Walker Branch watershed: changes during a 21-year period

    Science.gov (United States)

    Carl C. Trettin; D.W. Johnson; D.E. Todd

    1999-01-01

    A 21-yr perspective on changes in nutrient and C pools on undisturbed upland forest sites is provided. Plots originally representing four cover types have been sampled three times. On each plot, forest biomass, forest floor, and soil, to a depth of 60 cm, were measured, sampled, and analyzed for Ca, Mg, C, N, and P. Exchangeable soil Ca and Mg have declined in most...

  3. Assessment of water supply as an ecosystem service in a rural-urban watershed in southwestern Mexico City.

    Science.gov (United States)

    Jujnovsky, Julieta; González-Martínez, Teresa Margarita; Cantoral-Uriza, Enrique Arturo; Almeida-Leñero, Lucia

    2012-03-01

    Studies from the ecosystem services perspective can provide a useful framework because they allow us to fully examine the benefits that humans obtain from socio-ecological systems. Mexico City, the second largest city in the world, has faced severe problems related to water shortages, which have worsened due to increasing population. Demand for space has forced changes in land cover, including covering areas that are essential for groundwater recharge. The city has 880 km(2) of forest areas that are crucial for the water supply. The Magdalena River Watershed was chosen as a model because it is a well-preserved zone within Mexico City and it provides water for the population. The general aim of this study was to assess the ecosystem service of the water supply in the Magdalena River Watershed by determining its water balance (SWAT model) and the number of beneficiaries of the ecosystem services. The results showed that the watershed provides 18.4 hm(3) of water per year. Baseflow was dominant, with a contribution of 85%, while surface runoff only accounted for 15%. The zone provides drinking water to 78,476 inhabitants and could supply 153,203 potential beneficiaries. This work provides an example for understanding how ecosystem processes determine the provision of ecosystem services and benefits to the population in a rural-urban watershed in Mexico City.

  4. Effects of Extensive Beetle-Induced Forest Mortality on Aromatic Organic Carbon Loading and Disinfection Byproduct Formation Potential

    Science.gov (United States)

    Brouillard, B.; Mikkelson, K. M.; Dickenson, E.; Sharp, J.

    2015-12-01

    Recent drought and warmer temperatures associated with climate change have caused increased pest-induced forest mortality with impacts on biogeochemical and hydrologic processes. To better understand the seasonal impacts of bark beetle infestation on water quality, samples were collected regularly over two overlapping snow free seasons at surface water intakes of six water treatment facilities in the Rocky Mountain region of Colorado displaying varying levels of bark beetle infestation (high >40%, moderate 20-40%, and low <20%). Organic carbon concentrations were typically 3 to 6 times higher in waters sourced from high beetle-impacted watersheds compared to moderate and low impact watersheds, revealing elevated specific ultraviolet absorbance, fluorescence, and humic-like intensity indicative of elevated aromatic carbon signatures. Accordingly, an increase in disinfection byproduct (DBP) formation potential of 400 to 600% was quantified when contrasted with watersheds containing less tree mortality. Beetle impact exasperated seasonal increases in carbon loading and DBP formation potential following both runoff and precipitation events indicating windows when enhanced water treatment may be utilized by water providers in highly infested regions. Additionally, elevated carbon concentrations throughout the summer and fall along with peaks following precipitation events provide evidence of shifting hydrologic flow paths in areas experiencing high forest mortality from decreased tree water uptake and interception. Collectively, these results demonstrate the need for continued watershed protection and monitoring with a changing climate as the resultant perturbations can have adverse effects on biogeochemistry and water quality in heavily impacted areas.

  5. Variability in above- and belowground carbon stocks in a Siberian larch watershed

    Directory of Open Access Journals (Sweden)

    E. E. Webb

    2017-09-01

    Full Text Available Permafrost soils store between 1330 and 1580 Pg carbon (C, which is 3 times the amount of C in global vegetation, almost twice the amount of C in the atmosphere, and half of the global soil organic C pool. Despite the massive amount of C in permafrost, estimates of soil C storage in the high-latitude permafrost region are highly uncertain, primarily due to undersampling at all spatial scales; circumpolar soil C estimates lack sufficient continental spatial diversity, regional intensity, and replication at the field-site level. Siberian forests are particularly undersampled, yet the larch forests that dominate this region may store more than twice as much soil C as all other boreal forest types in the continuous permafrost zone combined. Here we present above- and belowground C stocks from 20 sites representing a gradient of stand age and structure in a larch watershed of the Kolyma River, near Chersky, Sakha Republic, Russia. We found that the majority of C stored in the top 1 m of the watershed was stored belowground (92 %, with 19 % in the top 10 cm of soil and 40 % in the top 30 cm. Carbon was more variable in surface soils (10 cm; coefficient of variation (CV  =  0.35 between stands than in the top 30 cm (CV  =  0.14 or soil profile to 1 m (CV  =  0.20. Combined active-layer and deep frozen deposits (surface – 15 m contained 205 kg C m−2 (yedoma, non-ice wedge and 331 kg C m−2 (alas, which, even when accounting for landscape-level ice content, is an order of magnitude more C than that stored in the top meter of soil and 2 orders of magnitude more C than in aboveground biomass. Aboveground biomass was composed of primarily larch (53 % but also included understory vegetation (30 %, woody debris (11 % and snag (6 % biomass. While aboveground biomass contained relatively little (8 % of the C stocks in the watershed, aboveground processes were linked to thaw depth and

  6. Effect of timber harvesting on stormflow characteristics in headwater streams of managed, forested watersheds in the Upper Gulf Coastal Plain in Mississippi

    Science.gov (United States)

    Byoungkoo Choi; Jeff A. Hatten; Janet C. Dewey; Kyoichi Otsuki; Dusong Cha

    2013-01-01

    Headwater streams are crucial parts of overall watershed dynamics because they comprise more than 50–80% of stream networks and watershed land areas. This study addressed the influence of headwater areas (ephemeral and intermittent) on stormflow characteristics following harvest within three first–order catchments in the Upper Gulf Coastal Plain of Mississippi. Four...

  7. Revealing Forest Harvesting Effects on Large Peakflows in Rain-On-Snow Environment with a New Stochastic Framework

    Science.gov (United States)

    Rong, W. N.; Alila, Y.

    2017-12-01

    Using nine pairs of control-treatment watersheds with varying climate, physiography, and harvesting practices in the Rain-On-Snow (ROS) environment of the Pacific Northwest region, we explore the linkage between environmental control and the sensitivity of peakflow response to harvesting effects. Compared to previous paired watershed studies in ROS environment, we employed an experimental design of Frequency Pairing to isolate the effects of disturbances on systems' response. In contrary, the aspect of changing frequency distributions is not commonly invoked in previous literatures on the topic of forests and floods. Our results show how harvesting can dramatically increase the magnitude of all peakflows on record and how such effects can increase with increasing return periods, as a consequence of substantial increases to the mean and variance of the peakflow frequency distribution. Most critically, peakflows with return period larger than 10 years can increase in frequency, where the larger the peakflow event the more frequent it may become. The sensitivity of the upper tail of the frequency distribution of peakflows was found to be linked to the physiographic and climatic characteristics via a unifying synchronization / desynchronization spatial scaling mechanism that controls the generation of rain-on-snow runoff. This new physically-based stochastic hydrology understanding on the response of watersheds in ROS environments runs counter the deterministic prevailing wisdom of forest hydrology, which presumes a limited and diminishing role of forest cover as the magnitude of the peakflow event increases. By demonstrating the need for invoking the dimension of frequency in the understanding and prediction of the effects of harvesting on peakflows, findings from this study suggested that pure deterministic hypotheses and experimental designs that solely focusing on the changing magnitude of peakflows have been misguiding forest hydrology research for over a century

  8. Evaluating watershed protection programs in New York City's Cannonsville Reservoir source watershed using SWAT-HS

    Science.gov (United States)

    Hoang, L.; Mukundan, R.; Moore, K. E.; Owens, E. M.; Steenhuis, T. S.

    2017-12-01

    New York City (NYC)'s reservoirs supply over one billion gallons of drinking water each day to over nine million consumers in NYC and upstate communities. The City has invested more than $1.5 billion in watershed protection programs to maintain a waiver from filtration for the Catskill and Delaware Systems. In the last 25 years, the NYC Department of Environmental Protection (NYCDEP) has implemented programs in cooperation with upstate communities that include nutrient management, crop rotations, improvement of barnyards and manure storage, implementing tertiary treatment for Phosphorus (P) in wastewater treatment plants, and replacing failed septic systems in an effort to reduce P loads to water supply reservoirs. There have been several modeling studies evaluating the effect of agricultural Best Management Practices (BMPs) on P control in the Cannonsville watershed in the Delaware System. Although these studies showed that BMPs would reduce dissolved P losses, they were limited to farm-scale or watershed-scale estimates of reduction factors without consideration of the dynamic nature of overland flow and P losses from variable source areas. Recently, we developed the process-based SWAT-Hillslope (SWAT-HS) model, a modified version of the Soil and Water Assessment Tool (SWAT) that can realistically predict variable source runoff processes. The objective of this study is to use the SWAT-HS model to evaluate watershed protection programs addressing both point and non-point sources of P. SWAT-HS predicts streamflow very well for the Cannonsville watershed with a daily Nash Sutcliffe Efficiency (NSE) of 0.85 at the watershed outlet and NSE values ranging from 0.56 - 0.82 at five other locations within the watershed. Based on good hydrological prediction, we applied the model to predict P loads using detailed P inputs that change over time due to the implementation of watershed protection programs. Results from P model predictions provide improved projections of P

  9. Forest restoration as a strategy to mitigate climate impacts on wildfire, vegetation, and water in semiarid forests.

    Science.gov (United States)

    O'Donnell, Frances C; Flatley, William T; Springer, Abraham E; Fulé, Peter Z

    2018-06-25

    Climate change and wildfire are interacting to drive vegetation change and potentially reduce water quantity and quality in the southwestern United States, Forest restoration is a management approach that could mitigate some of these negative outcomes. However, little information exists on how restoration combined with climate change might influence hydrology across large forest landscapes that incorporate multiple vegetation types and complex fire regimes. We combined spatially explicit vegetation and fire modeling with statistical water and sediment yield models for a large forested landscape (335,000 ha) on the Kaibab Plateau in northern Arizona, USA. Our objective was to assess the impacts of climate change and forest restoration on the future fire regime, forest vegetation, and watershed outputs. Our model results predict that the combination of climate change and high-severity fire will drive forest turnover, biomass declines, and compositional change in future forests. Restoration treatments may reduce the area burned in high-severity fires and reduce conversions from forested to non-forested conditions. Even though mid-elevation forests are the targets of restoration, the treatments are expected to delay the decline of high-elevation spruce-fir, aspen, and mixed conifer forests by reducing the occurrence of high-severity fires that may spread across ecoregions. We estimate that climate-induced vegetation changes will result in annual runoff declines of up to 10%, while restoration reduced or reversed this decline. The hydrologic model suggests that mid-elevation forests, which are the targets of restoration treatments, provide around 80% of runoff in this system and the conservation of mid- to high-elevation forests types provides the greatest benefit in terms of water conservation. We also predict that restoration treatments will conserve water quality by reducing patches of high-severity fire that are associated with high sediment yield. Restoration

  10. Land Use Cover Changes and Run Off Potention of Cipunten Agung Watershed Banten

    Science.gov (United States)

    Karima, A.; Kaswanto, R. L.

    2017-10-01

    The changes of landscape form such as Land Use Cover Changes (LUCC) of Cipunten Agung watershed could be identified periodically in 1995, 2005, and 2015. In general, land utilization in Cipunten Agung classified into protected region and cultivated region. In 2011, total of protected area is 885.80 ha or 22.54% of watershed area. Those conditions affected both positively to the community development and negatively to the water quantity condition in Cipunten Agung such as flooding, run off, and erosion. Therefore, the purpose of this research is to analyze LUCC impacts to run off potential in Cipunten Agung watershed. Supervised classification method and Soil Conservation Services (Qscs) approach were correlated to determine the figure out an optimal solution to reduce the rate of LUCC. Cipunten Agung watershed imagery was classified into five classes, namely water bodies, forest, cultivated tree, settlement and paddy field. The result shows that area of cultivation tree and paddy fields are larger than others in midstream, and settlement is denser in downstream, particularly at riparian landscapes. The LUCC into paddy field often occur at two period 1995 to 2005 and 2005 to 2015 with several area are 530.92 ha and 388.17 ha. The Qscs method calculation result for 1995 until 2015 was affected by land use cover composition in each year and it was defined by Curve Number (CN). High rainfall in 1995 was generating high run off potential volume. Nevertheless, curve number value was increase get near to 100, which indicate the potential of run off volume increases along with LUCC in each year, those are 70.95; 72.47; and 72.81.

  11. Throughfall in different forest stands of Iperó, São Paulo

    Directory of Open Access Journals (Sweden)

    Esthevan Augusto Goes Gasparoto

    2014-06-01

    Full Text Available In forestry, throughfall (Pi is that fraction of rainfall that runs directly through the tree canopy and reaches the ground. It is characterized as the main source of water supply in a watershed. This study aimed to analyze the dynamics of throughfall in three types of forest stands, namely Eucalyptus cloeziana, Pinus sp. and seasonal semideciduous forest (FES, all located in Ipanema National Forest, in the municipality of Iperó-SP. In each stand, a 300 m² plot was established in which ten rain gauges were installed for monitoring throughfall, and three rain gauges were installed in an open area adjacent to the stand for measuring gross precipitation (P. At the end of 25 observations, it was observed that, relative to P values, Pi values were 76.2% in semideciduous forest (FES, 85.1% in E.cloeziana forest and 84.0% in Pinus sp forest. In addition, comparing these stands, a larger leaf canopy coverage and consequently greater capability for water retention was noted in the semideciduous forest. However, no statistical differences were observed (P<0.05 between the stands of interest regarding throughfall.

  12. 75 FR 43138 - Ochoco National Forest, Lookout Mountain Ranger District; Oregon; Howard Elliot Johnson Fuels and...

    Science.gov (United States)

    2010-07-23

    ... Analysis. Generally speaking, the Watershed Analysis determined that vegetation condition in the... scoping process. The Ochoco National Forest will give notice of the full environmental analysis and.... DATES: Comments concerning the scope of the analysis must be received by August 23, 2010. The draft...

  13. Study of Tree and Shrub Species Diversity in Forestry Plans with Different Forest Management

    Directory of Open Access Journals (Sweden)

    nooreddin noorian

    2017-12-01

    Full Text Available The aim of this research was to investigate the diversity of tree and shrub species in forestry plan in a watershed and in almost the same ecological conditions but different in forest management plan in the part of Golestan province forest. To this end, the 6675 hectares of the watershed number of 85 in 5 different plans in series one (30-year forestry plan with University Scientific Management, series two Doctor Bahramnia (without implementation and protection, series four Shamoshak, Naharkhoran plan and Sad Abad plan were selected. Inventory grid was designed by a systematic cluster sampling method with 239 circle plots in the study area. In each sample, species composition and diameter at breast height of trees and shrubs were measured. Species diversity in different series, were performed by calculating the heterogeneity indices, species richness and evenness. Statistical analysis of significant differences between the values of biodiversity of woody species among different series was performed by Duncan’s test. The results showed that biodiversity of woody species in the one and two series of Shastkalateh forest under academic management was better than other plans and forestry plan of Naharkhoran is in an unfavorable situation in terms of diversity indices.

  14. Fena Valley Reservoir watershed and water-balance model updates and expansion of watershed modeling to southern Guam

    Science.gov (United States)

    Rosa, Sarah N.; Hay, Lauren E.

    2017-12-01

    In 2014, the U.S. Geological Survey, in cooperation with the U.S. Department of Defense’s Strategic Environmental Research and Development Program, initiated a project to evaluate the potential impacts of projected climate-change on Department of Defense installations that rely on Guam’s water resources. A major task of that project was to develop a watershed model of southern Guam and a water-balance model for the Fena Valley Reservoir. The southern Guam watershed model provides a physically based tool to estimate surface-water availability in southern Guam. The U.S. Geological Survey’s Precipitation Runoff Modeling System, PRMS-IV, was used to construct the watershed model. The PRMS-IV code simulates different parts of the hydrologic cycle based on a set of user-defined modules. The southern Guam watershed model was constructed by updating a watershed model for the Fena Valley watersheds, and expanding the modeled area to include all of southern Guam. The Fena Valley watershed model was combined with a previously developed, but recently updated and recalibrated Fena Valley Reservoir water-balance model.Two important surface-water resources for the U.S. Navy and the citizens of Guam were modeled in this study; the extended model now includes the Ugum River watershed and improves upon the previous model of the Fena Valley watersheds. Surface water from the Ugum River watershed is diverted and treated for drinking water, and the Fena Valley watersheds feed the largest surface-water reservoir on Guam. The southern Guam watershed model performed “very good,” according to the criteria of Moriasi and others (2007), in the Ugum River watershed above Talofofo Falls with monthly Nash-Sutcliffe efficiency statistic values of 0.97 for the calibration period and 0.93 for the verification period (a value of 1.0 represents perfect model fit). In the Fena Valley watershed, monthly simulated streamflow volumes from the watershed model compared reasonably well with the

  15. Bringing Together Users and Developers of Forest Biomass Maps

    Science.gov (United States)

    Brown, Molly Elizabeth; Macauley, Molly K.

    2012-01-01

    Forests store carbon and thus represent important sinks for atmospheric carbon dioxide. Reducing uncertainty in current estimates of the amount of carbon in standing forests will improve precision of estimates of anthropogenic contributions to carbon dioxide in the atmosphere due to deforestation. Although satellite remote sensing has long been an important tool for mapping land cover, until recently aboveground forest biomass estimates have relied mostly on systematic ground sampling of forests. In alignment with fiscal year 2010 congressional direction, NASA has initiated work toward a carbon monitoring system (CMS) that includes both maps of forest biomass and total carbon flux estimates. A goal of the project is to ensure that the products are useful to a wide community of scientists, managers, and policy makers, as well as to carbon cycle scientists. Understanding the needs and requirements of these data users is helpful not just to the NASA CMS program but also to the entire community working on carbon-related activities. To that end, this meeting brought together a small group of natural resource managers and policy makers who use information on forests in their work with NASA scientists who are working to create aboveground forest biomass maps. These maps, derived from combining remote sensing and ground plots, aim to be more accurate than current inventory approaches when applied at local and regional scales. Meeting participants agreed that users of biomass information will look to the CMS effort not only to provide basic data for carbon or biomass measurements but also to provide data to help serve a broad range of goals, such as forest watershed management for water quality, habitat management for biodiversity and ecosystem services, and potential use for developing payments for ecosystem service projects. Participants also reminded the CMS group that potential users include not only public sector agencies and nongovernmental organizations but also the

  16. Spatiotemporal variation of watershed health propensity through reliability-resilience-vulnerability based drought index (case study: Shazand Watershed in Iran).

    Science.gov (United States)

    Sadeghi, Seyed Hamidreza; Hazbavi, Zeinab

    2017-06-01

    Quantitative response of the watershed health to climate variability is of critical importance for watershed managers. However, existing studies seldom considered the impact of climate variability on watershed health. The present study therefore aimed to analyze the temporal and spatial variability of reliability (R el ), resilience (R es ) and vulnerability (V ul ) indicators in node years of 1986, 1998, 2008 and 2014 in connection with Standardized Precipitation Index (SPI) for 24 sub-watersheds in the Shazand Watershed of Markazi Province in Iran. The analysis was based on rainfall variability as one of the main climatic drivers. To achieve the study purposes, the monthly rainfall time series of eight rain gauge stations distributed across the watershed or neighboring areas were analyzed and corresponding SPIs and R el R es V ul indicators were calculated. Ultimately, the spatial variation of SPI oriented R el R es V ul was mapped for the study watershed using Geographic Information System (GIS). The average and standard deviation of SPI-R el R es V ul index for the study years of 1986, 1998, 2008 and 2014 was obtained 0.240±0.025, 0.290±0.036, 0.077±0.0280 and 0.241±0.081, respectively. In overall, the results of the study proved the spatiotemporal variations of SPI-R el R es V ul watershed health index in the study area. Accordingly, all the sub-watersheds of the Shazand Watershed were grouped in unhealthy and very unhealthy conditions in all the study years. For 1986 and 1998 all the sub-watersheds were assessed in unhealthy status. Whilst, it declined to very unhealthy condition in 2008 and then some 75% of the watershed ultimately referred again to unhealthy and the rest still remained under very unhealthy conditions in 2014. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Comparison of sediment and nutrient export and runoff characteristics from watersheds with centralized versus distributed stormwater management.

    Science.gov (United States)

    Hopkins, Kristina G; Loperfido, J V; Craig, Laura S; Noe, Gregory B; Hogan, Dianna M

    2017-12-01

    Stormwater control measures (SCMs) are used to retain stormwater and pollutants. SCMs have traditionally been installed in a centralized manner using detention to mitigate peak flows. Recently, distributed SCM networks that treat runoff near the source have been increasingly utilized. The aim of this study was to evaluate differences among watersheds that vary in SCM arrangement by assessing differences in baseflow nutrient (NO x -N and PO 4 - ) concentrations and fluxes, stormflow export of suspended sediments and particulate phosphorus (PP), and runoff characteristics. A paired watershed approach was used to compare export between 2004 and 2016 from one forested watershed (For-MD), one suburban watershed with centralized SCMs (Cent-MD), and one suburban watershed with distributed SCMs (Dist-MD). Results indicated baseflow nitrate (NO x -N) concentrations typically exceeded 1 mg-N/L in all watersheds and were highest in Dist-MD. Over the last 10 years in Dist-MD, nitrate concentrations in both stream baseflow and in a groundwater well declined as land use shifted from agriculture to suburban. Baseflow nitrate export temporarily increased during the construction phase of SCM development in Dist-MD. This temporary pulse of nitrate may be attributed to the conversion of sediment control facilities to SCMs and increased subsurface flushing as infiltration SCMs came on line. During storm flow, Dist-MD tended to have less runoff and lower maximum specific discharge than Cent-MD for small events (runoff responses became increasingly similar to Cent-MD with increasing precipitation (>1.3 cm). Mass export estimated during paired storm events indicated Dist-MD exported 30% less sediment and 31% more PP than Cent-MD. For large precipitation events, export of sediment and PP was similar among all three watersheds. Results suggest that distributed SCMs can reduce runoff and sediment loads during small rain events compared to centralized SCMs, but these differences become

  18. Difference of stand-scale transpiration between ridge and riparian area in a watershed with Japanese cypress plantation

    Science.gov (United States)

    Kume, T.; Tsuruta, K.; Komatsu, H.; Shinohara, Y.; Otsuki, K.

    2011-12-01

    Several different methods to assess water use are available, and the sap flux measurement technique is one of the most promising methods, especially in monotonous watershed. Previously, three spatial levels of scaling have been used to obtain bottom-up transpiration estimates based on the sap flux technique: from within-tree to tree, from tree to stand, and from stand to watershed or landscape. Although there are considerable variations that must be taken into account at each step, few studies have examined plot-to-plot variability of stand-scale transpirations. To design optimum sampling method to accurately estimate transpiration at the watershed-scale, it is indispensable to understand heterogeneity of stand-scale transpiration in a forested watershed and the factors determining the heterogeneity. This study was undertaken to clarify differences of stand-scale transpirations within a watershed and the factors determining the differences. To this aim, we conducted sap flux-based transpiration estimates in two plots such as a lower riparian (RZ) and an upper ridge (UZ) zone in a watershed with Japanese cypress plantation, Kyushu, Japan in two years. Tree height and diameter of breast height (DBH) were lager in RZ than those of UZ. The stand sapwood area (As) was lager in RZ than UZ (21.9 cm2h a-1, 16.8 cm2ha-1, respectively). Stand mean sap flux (Js) in RZ was almost same as that of UZ when relatively lower Js, while, Js in RZ was higher than that of UZ when relatively higher Js (i.e., bright days in summer season). Consequently, daily stand-scale transpiration (E), which is the multiple of As and Js, differed by two times between RZ and UZ in summer season. This study found significant heterogeneity of stand-scale transpiration within the watershed and that the differences could be caused by two aspects such as stand structure and sap flux velocity.

  19. Climate change and watershed mercury export in a Coastal Plain watershed

    Science.gov (United States)

    Heather Golden; Christopher D. Knightes; Paul A. Conrads; Toby D. Feaster; Gary M. Davis; Stephen T. Benedict; Paul M. Bradley

    2016-01-01

    Future changes in climatic conditions may affect variations in watershed processes (e.g., hydrological, biogeochemical) and surface water quality across a wide range of physiographic provinces, ecosystems, and spatial scales. How such climatic shifts will impact watershed mercury (Hg) dynamics and hydrologically-driven Hg transport is a significant concern.

  20. Linking the Molecular Signature of Heteroatomic Dissolved Organic Matter to Watershed Characteristics in World Rivers.

    Science.gov (United States)

    Wagner, Sasha; Riedel, Thomas; Niggemann, Jutta; Vähätalo, Anssi V; Dittmar, Thorsten; Jaffé, Rudolf

    2015-12-01

    Large world rivers are significant sources of dissolved organic matter (DOM) to the oceans. Watershed geomorphology and land use can drive the quality and reactivity of DOM. Determining the molecular composition of riverine DOM is essential for understanding its source, mobility and fate across landscapes. In this study, DOM from the main stem of 10 global rivers covering a wide climatic range and land use features was molecularly characterized via ultrahigh-resolution Fourier-transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). FT-ICR mass spectral data revealed an overall similarity in molecular components among the rivers. However, when focusing specifically on the contribution of nonoxygen heteroatomic molecular formulas (CHON, CHOS, CHOP, etc.) to the bulk molecular signature, patterns relating DOM composition and watershed land use became apparent. Greater abundances of N- and S-containing molecular formulas were identified as unique to rivers influenced by anthropogenic inputs, whereas rivers with primarily forested watersheds had DOM signatures relatively depleted in heteroatomic content. A strong correlation between cropland cover and dissolved black nitrogen was established when focusing specifically on the pyrogenic class of compounds. This study demonstrated how changes in land use directly affect downstream DOM quality and could impact C and nutrient cycling on a global scale.

  1. Origins and transport of aquatic dioxins in the Japanese watershed: soil contamination, land use, and soil runoff events.

    Science.gov (United States)

    Kanematsu, Masakazu; Shimizu, Yoshihisa; Sato, Keisuke; Kim, Suejin; Suzuki, Tasuma; Park, Baeksoo; Saino, Reiko; Nakamura, Masafumi

    2009-06-15

    Significant dioxins accumulations in Japanese forests and paddy fields have been observed, and surface soil runoff caused by rainfall and irrigation (i.e., soil puddling in paddy fields) results in dioxins input into the aquatic environment. An extensive investigation into the origins and transport of aquatic dioxins in the Yasu watershed, Japan was conducted considering surface soil contamination level, land use, and type of soil runoff event (i.e., irrigation runoff [IR], rainfall runoff [RR], and base flow [BF]). Combined use of the chemically activated luciferase expression (CALUX) assay together with high-resolution gas chromatography and high-resolution mass spectrometry (HRGC/HRMS) efficiently enabled this study, so that origins, transport, and dynamic movement of aquatic dioxins in the watershed were revealed. The particulate organic carbon normalized particulate-dioxins WHO-toxic equivalent (TEQ) concentration predicted by the CALUX assay (Spar) was found to be a convenient molecular marker to indicate origins of aquatic dioxins and clearly reflect surface soil contamination level, land use, and soil runoff events. Using experimental results and theoretical modeling, the annual loading amount of dioxins at the middle reach of the river was estimated to be 0.458 mg WHO-TEQ in 2004. More than 96.6% of the annual loading amount was attributed to RR and derived almost evenly from forest and paddy fields at the study location. Because the annual loading amount at the middle reach is less than 0.5% of the total dioxins accumulated in the upper basin, dioxins runoff from the Japanese watershed will continue. This study shows that the combined use of the bioassay with HRGC/HRMS can provide new insights into dioxins transport and fate in the environment.

  2. Simulations of forest mortality in Colorado River basin

    Science.gov (United States)

    Wei, L.; Xu, C.; Johnson, D. J.; Zhou, H.; McDowell, N.

    2017-12-01

    The Colorado River Basin (CRB) had experienced multiple severe forest mortality events under the recent changing climate. Such forest mortality events may have great impacts on ecosystem services and water budget of the watershed. It is hence important to estimate and predict the forest mortality in the CRB with climate change. We simulated forest mortality in the CRB with a model of plant hydraulics within the FATES (the Functionally Assembled Terrestrial Ecosystem Simulator) coupled to the DOE Earth System model (ACME: Accelerated Climate Model of Energy) at a 0.5 x 0.5 degree resolution. Moreover, we incorporated a stable carbon isotope (δ13C) module to ACME(FATE) and used it as a new predictor of forest mortality. The δ13C values of plants with C3 photosynthetic pathway (almost all trees are C3 plants) can indicate the water stress plants experiencing (the more intensive stress, the less negative δ13C value). We set a δ13C threshold in model simulation, above which forest mortality initiates. We validate the mortality simulations with field data based on Forest Inventory and Analysis (FIA) data, which were aggregated into the same spatial resolution as the model simulations. Different mortality schemes in the model (carbon starvation, hydraulic failure, and δ13C) were tested and compared. Each scheme demonstrated its strength and the plant hydraulics module provided more reliable simulations of forest mortality than the earlier ACME(FATE) version. Further testing is required for better forest mortality modelling.

  3. Soilaluminum, iron, and phosphorus dynamics in response to long-term experimental nitrogen and sulfur additions at the Bear Brook Watershed in Maine, USA

    Science.gov (United States)

    Jessica Sherman; Ivan J. Fernandez; Stephen A. Norton; Tsutomu Ohno; Lindsey E. Rustad

    2006-01-01

    Atmospheric deposition of nitrogen (N) and sulfur (S) containing compounds affects soil chemistry in forested ecosystems through (1) acidification and the depletion of base cations, (2) metal mobilization, particularly aluminum (Al), and iron (Fe), (3) phosphorus (P) mobilization, and (4) N accumulation. The Bear BrookWatershed in Maine (BBWM) is a long-term paired...

  4. Assessing the protection function of Alpine forest ecosystems using BGC modelling theory

    Science.gov (United States)

    Pötzelsberger, E.; Hasenauer, H.; Petritsch, R.; Pietsch, S. A.

    2009-04-01

    The purpose of this study was to assess the protection function of forests in Alpine areas by modelling the flux dynamics (water, carbon, nutrients) within a watershed as they may depend on the vegetation pattern and forest management impacts. The application case for this study was the catchment Schmittenbach, located in the province of Salzburg. Data available covered the hydrology (rainfall measurements from 1981 to 1998 and runoff measurements at the river Schmittenbach from 1981 to 2005), vegetation dynamics (currently 69% forest, predominantly Norway Spruce). The method of simulating the forest growth and water outflow was validated. For simulations of the key ecosystem processes (e.g. photosynthesis, carbon and nitrogen allocation in the different plant parts, litter fall, mineralisation, tree water uptake, transpiration, rainfall interception, evaporation, snow accumulation and snow melt, outflow of spare water) the biogeochemical ecosystem model Biome-BGC was applied. Relevant model extensions were the tree species specific parameter sets and the improved thinning regime. The model is sensitive to site characteristics and needs daily weather data and information on the atmospheric composition, which makes it sensitive to higher CO2-levels and climate change. For model validation 53 plots were selected covering the full range of site quality and stand age. Tree volume and soil was measured and compared with the respective model results. The outflow for the watershed was predicted by combining the simulated forest-outflow (derived from plot-outflow) with the outflow from the non-forest area (calculated with a fixed outflow/rainfall coefficient (OC)). The analysis of production and water related model outputs indicated that mechanistic modelling can be used as a tool to assess the performance of Alpine protection forests. The Water Use Efficiency (WUE), the ratio of Net primary production (NPP) and Transpiration, was found the highest for juvenile stands (

  5. Hydrologic Responses to Land Use Change in the Loess Plateau: Case Study in the Upper Fenhe River Watershed

    Directory of Open Access Journals (Sweden)

    Zhixiang Lu

    2015-01-01

    Full Text Available We applied an integrated approach to investigate the impacts of land use and land cover (LULC changes on hydrology at different scales in the Loess Plateau of China. Hydrological modeling was conducted for the LULC maps from remote sensing images at two times in the Upper Fenhe River watershed using the SWAT model. The main LULC changes in this watershed from 1995 to 2010 were the transformation of farmland into forests, grassland, and built-up land. The simulation results showed that forested land contributed more than any other LULC class to water yield, but built-up land had most impact due to small initial loss and infiltration. At basin scale, a comparison of the simulated hydrological components of two LULC maps showed that there were slight increases in average annual potential evapotranspiration, actual evapotranspiration, and water yield, but soil water decreased, between the two intervals. In subbasins, obvious LULC changes did not have clear impacts on hydrology, and the impacts may be affected by precipitation conditions. By linking a hydrological model to remote sensing image analysis, our approach of quantifying the impacts of LULC changes on hydrology at different scales provide quantitative information for stakeholders in making decisions for land and water resource management.

  6. Social Exclusion in Watershed Development: Evidence From the Indo-German Watershed Development Project in Maharashtra

    Directory of Open Access Journals (Sweden)

    Eshwer Kale

    2011-09-01

    Full Text Available The concept of social exclusion is context-specific and there is no uniform paradigm of exclusion across the world. This paper attempts to analyse exclusion of resource-poor groups in watershed development programmes in the Indian context. It aims to explore excluded community groups from the perspective of people’s equal opportunity and equal access to newly generated economic benefits in watershed development programmes. The paper also traces the determinant factors responsible for denial and exclusion of resource-poor groups and describes the detailed processes involved in their exclusion from institutional and livelihood opportunities in watershed programmes. At the same time, the paper also explores suggestions and views of resource-poor groups about their meaningful social inclusion in watershed programme. The Gadiwat Indo-German Watershed Development Project in Aurangabad district in the State of Maharashtra is studied in detail in terms of its social, economic and political realities through mix-method and multi-stakeholder approaches. The key findings of the paper are that landownership, caste, gender, membership in village institutions and/or watershed institutions or close relationship with members, as well as the limitations of the programme guidelines, are the major determinants of institutional inclusion and the extent of resulting economic benefits. The exclusion of resource-poor groups mainly takes the form of their exclusion from institutional representation. In order to promote meaningful social inclusion of resource-poor groups, there is need for a more livelihood-oriented focus and their equal representation and participation in watershed institutions.

  7. Watershed Management: Lessons from Common Property Theory

    Directory of Open Access Journals (Sweden)

    John Kerr

    2007-10-01

    Full Text Available Watershed development is an important component of rural development and natural resource management strategies in many countries. A watershed is a special kind of common pool resource: an area defined by hydrological linkages where optimal management requires coordinated use of natural resources by all users. Management is difficult because natural resources comprising the watershed system have multiple, conflicting uses, so any given management approach will spread benefits and costs unevenly among users. To address these challenges, watershed approaches have evolved from more technocratic to a greater focus on social organization and participation. However, the latter cannot necessarily be widely replicated. In addition, participatory approaches have worked better at a small scale, but hydrological relationships cover a larger scale and some projects have faced tradeoffs in choosing between the two. Optimal approaches for future efforts are not clear, and theories from common property research do not support the idea that complex watershed management can succeed everywhere. Solutions may include simplifying watershed projects, pursuing watershed projects where conditions are favorable, and making other investments elsewhere, including building the organizational capacity that can facilitate watershed management.

  8. Water and Poverty in Two Colombian Watersheds

    Directory of Open Access Journals (Sweden)

    Nancy Johnson

    2009-02-01

    Full Text Available Watersheds, especially in the developing world, are increasingly being managed for both environmental conservation and poverty alleviation. How complementary are these objectives? In the context of a watershed, the actual and potential linkages between land and water management and poverty are complex and likely to be very site specific and scale dependent. This study analyses the importance of watershed resources in the livelihoods of the poor in two watersheds in the Colombian Andes. Results of the participatory poverty assessment reveal significant decreases in poverty in both watersheds over the past 25 years, which was largely achieved by the diversification of livelihoods outside of agriculture. Water is an important resource for household welfare. However, opportunities for reducing poverty by increasing the quantity or quality of water available to the poor may be limited. While improved watershed management may have limited direct benefits in terms of poverty alleviation, there are important indirect linkages between watershed management and poverty, mainly through labour and service markets. The results suggest that at the level of the watershed the interests of the rich and the poor are not always in conflict over water. Sectoral as well as socio-economic differences define stakeholder groups in watershed management. The findings have implications for policymakers, planners and practitioners in various sectors involved in the implementation of integrated water resources management (IWRM.

  9. Jordan Lake Watershed Protection District

    Data.gov (United States)

    Town of Chapel Hill, North Carolina — Polygon representing the area of the Jordan Lake Watershed Protection District. The Watershed Protection District (PDF) is a sensitive area of land that drains to...

  10. Improving SWAT for simulating water and carbon fluxes of forest ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Qichun; Zhang, Xuesong

    2016-11-01

    As a widely used watershed model for assessing impacts of anthropogenic and natural disturbances on water quantity and quality, the Soil and Water Assessment Tool (SWAT) has not been extensively tested in simulating water and carbon fluxes of forest ecosystems. Here, we examine SWAT simulations of evapotranspiration (ET), net primary productivity (NPP), net ecosystem exchange (NEE), and plant biomass at ten AmeriFlux forest sites across the U.S. We identify unrealistic radiation use efficiency (Bio_E), large leaf to biomass fraction (Bio_LEAF), and missing phosphorus supply from parent material weathering as the primary causes for the inadequate performance of the default SWAT model in simulating forest dynamics. By further revising the relevant parameters and processes, SWAT’s performance is substantially improved. Based on the comparison between the improved SWAT simulations and flux tower observations, we discuss future research directions for further enhancing model parameterization and representation of water and carbon cycling for forests.

  11. Impacts of Land Use Change on the Natural Flow Regime: A Case Study in the Meramec River Watershed in Eastern Missouri, USA

    Science.gov (United States)

    Wu, C. L.; Knouft, J.; Chu, M.

    2017-12-01

    The natural flow regime within a watershed can be considered as the expected temporal patterns of streamflow variation in the absence of human impacts. While ecosystems have evolved to function under these conditions, the natural flow regime of most rivers has been significantly altered by human activities. Land use change, including the development of agriculture and urbanization, is a primary cause of the loss of natural flow regimes. These changes have altered discharge volume, timing, and variability, and consequently affected the structure and functioning of river ecosystems. The Meramec River watershed is located in east central Missouri and changes in land use have been the primary factor impacting flow regimes across the watershed. In this study, a watershed model, the Soil and Water Assessment Tool (SWAT), was developed to simulate a long-term time series of streamflow (1978-2014) within the watershed. Model performance was evaluated using statistical metrics and graphical technique including R-squared, Nash-Sutcliffe efficiency, cumulative error, and 1:1-ratio comparison between observed and simulated variables. The calibrated and validated SWAT model was then used to quantify the responses of the watershed when it was a forested natural landscape. An Indicator of Hydrologic Alteration (IHA) approach was applied to characterize the flow regime under the current landcover conditions as well as the simulated natural flow regime under the no land use change scenario. Differences in intra- and inter-annual ecologically relevant flow metrics were then compared using SWAT model outputs in conjunction with the IHA approach based on model outputs from current and no land use change conditions. This study provides a watershed-scale understanding of effects of land use change on a river's flow variability and provides a framework for the development of restoration plans for heavily altered watersheds.

  12. Water-quality impacts from climate-induced forest die-off

    Science.gov (United States)

    Mikkelson, Kristin M.; Dickenson, Eric R. V.; Maxwell, Reed M.; McCray, John E.; Sharp, Jonathan O.

    2013-03-01

    Increased ecosystem susceptibility to pests and other stressors has been attributed to climate change, resulting in unprecedented tree mortality from insect infestations. In turn, large-scale tree die-off alters physical and biogeochemical processes, such as organic matter decay and hydrologic flow paths, that could enhance leaching of natural organic matter to soil and surface waters and increase potential formation of harmful drinking water disinfection by-products (DBPs). Whereas previous studies have investigated water-quantity alterations due to climate-induced, forest die-off, impacts on water quality are unclear. Here, water-quality data sets from water-treatment facilities in Colorado were analysed to determine whether the municipal water supply has been perturbed by tree mortality. Results demonstrate higher total organic carbon concentrations along with significantly more DBPs at water-treatment facilities using mountain-pine-beetle-infested source waters when contrasted with those using water from control watersheds. In addition to this differentiation between watersheds, DBP concentrations demonstrated an increase within mountain pine beetle watersheds related to the degree of infestation. Disproportionate DBP increases and seasonal decoupling of peak DBP and total organic carbon concentrations further suggest that the total organic carbon composition is being altered in these systems.

  13. Processes controlling silicon isotopic fractionation in a forested tropical watershed: Mule Hole Critical Zone Observatory (Southern India)

    Science.gov (United States)

    Riotte, Jean; Meunier, Jean-Dominique; Zambardi, Thomas; Audry, Stéphane; Barboni, Doris; Anupama, Krishnamurthy; Prasad, Srinivasan; Chmeleff, Jérôme; Poitrasson, Franck; Sekhar, Muddu; Braun, Jean-Jacques

    2018-05-01

    Assessing the dynamics of the silica cycle in the critical zone remains challenging, particularly within the soil, where multiple processes are involved. To improve our understanding of this cycle in the Tropics, and more specifically the role played by vegetation, we combined elemental Si mass balance with the δ30Si signatures of the compartments involved in the water-plant-rock interactions of a tropical forested watershed, Mule Hole (Southern India). To accomplish this, we analysed (1) the δ30Si values of present-day litter phytoliths from tree leaves and grass, as well as soil amorphous silica (ASi); (2) the Si isotope fractionation induced by phytolith dissolution; (3) the silicon mass balance inferred from isotopes at the soil-plant scale; and (4) the consistency between water sources and the δ30Si signatures in the ephemeral stream. The δ30Si values of present-day litter phytoliths and soil ASi vary within a narrow range of 1.10-1.40‰ for all samples, but two deep vertisol samples which likely trapped phytoliths from different vegetation growing under more humid conditions, as indicated by pollen analysis. A homogeneous signature of litter is a minimum condition for using δ30Si as a proxy for the litter/phytolith source of Si. However, litter-ash dissolution experiments demonstrate that the incipient dissolution of phytoliths fractionates Si isotopes, with the preferential dissolution of 28Si over 30Si yielding δ30Si values as low as -1.41‰. Values close to the whole-sample signatures, i.e., above 1‰, were recovered in the solution after a few hours of water-ash interaction. At the soil-plant scale, the average δ30Si value of soil-infiltrating solutions is slightly lighter than the average phytolith signature, which suggests phytoliths as the source of soil dissolved Si. The isotopic budget of dissolved Si within the soil layer, which was obtained based on previous elemental fluxes, is imbalanced. Equilibrating the isotopic budget would imply

  14. Nitrogen fate and Transport in Diverse Agricultural Watersheds

    Science.gov (United States)

    Essaid, H.; McCarthy, K. A.; Baker, N. T.

    2010-12-01

    Nitrogen mass budgets have been estimated for ten agricultural watersheds located in a range of hydrologic settings in order to understand the factors controlling the fate of nitrogen applied at the surface. The watersheds, study areas of the Agricultural Chemical Sources, Transport and Fate study of the U.S. Geological Survey National Water Quality Assessment Program, are located in Indiana (IN), Iowa (IA), Maryland (MD), Nebraska (NE), Mississippi (MS) and Washington (WA). They range in size from 7 to 1254 km2, with four of the watersheds nested within larger watersheds. Surface water outflow (normalized to watershed area) ranged from 4 to 83 cm/yr. Crops planted include corn, soybean, small grains, rice, cotton, orchards and vegetables. “Surplus nitrogen” was determined for each watershed by subtracting estimates of crop uptake and volatilization from estimates of nitrogen input from atmospheric deposition, plant fixation, and fertilizer and manure applications for the period from 1987 to 2004. This surplus nitrogen is transported though the watershed via surface and subsurface flow paths, while simultaneously undergoing transformations (such as denitrification and in-stream processing) that result in less export of nitrogen from the watershed. Surface-water discharge and concentration data were used to estimate the export of nitrogen from the watersheds (groundwater outflow from the watersheds was minimal). Subtracting nitrogen export from surplus nitrogen provides an estimate of the net amount of nitrogen removal occurring during internal watershed transport. Watershed average nitrogen surplus ranged from 6 to 49 kg-N/ha. The more permeable and/or greater water flux watersheds (MD, NE, and WA) tended to have larger surplus nitrogen, possibly due to less crop uptake caused by greater leaching and runoff of nitrogen. Almost all of the surplus nitrogen in the low permeability (MS) and tile drained watersheds (IA, IN) was exported from the watershed with

  15. The influence of watershed perturbation on mercury loading in the littoral biofilms: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Desrosiers, M.; Planas, D. [Quebec Univ., GEOTOP, Montreal. PQ, (Canada); Mucci, A.; Guignard, C. [McGill Univ., Dept. of Earth and Planetary Sciences, Montreal, PQ (Canada)

    1999-05-01

    Methylmercury accumulation in littoral biofilms associated with anthropogenic watershed perturbation (harvesting) was evaluated and compared to natural perturbation (forest fires) and undisturbed lakes. Communities in littoral zones are the main food resources for many fish species. In the littoral zone, biofilms are at the base of the food chain and may prove to be an important source of mercury to fish. A total of 15 lakes were studied, equally distributed among the three types of disturbances. Methylmercury analysis was done in biofilms grown on Teflon substrates suspended in the littoral zone. The methylmercury was extracted with 25 per cent KOH in methanol and its concentration measured by cold-vapour atomic fluorescence following ethylation and gas chromatographic separation. Preliminary results show that methylmercury concentrations on the substrates are correlated with the biofilm algal biomass. In turn, the algal biomass is correlated to the degree of watershed perturbation associated with increased nutrient input, i.e. an increase in biofilm biomass may lead to greater availability of methylmercury for organisms that feed on the algae. Based on these observations, it was suggested that algae may play a significant role in the bioaccumulation of methylmercury by higher trophic organisms. Watershed perturbations appear to increase the bioavailability of methylmercury for aquatic organisms by way of increased production and consumption of littoral biofilms. 11 refs.

  16. Evaluating the source of streamwater nitrate using d15N and d18O in nitrate in two watersheds in New Hampshire, USA

    Science.gov (United States)

    Linda H. Pardo; Carol Kendall; Jennifer Pett-Ridge; Cecily C.Y. Chang; Cecily C.Y. Chang

    2004-01-01

    The natural abundance of nitrogen and oxygen isotopes in nitrate can be a powerful tool for identifying the source of nitrate in streamwater in forested watersheds, because the two main sources of nitrate, atmospheric deposition and microbial nitrification, have distinct d18O values. Using a simple mixing model, we estimated the relative fractions in streamwater...

  17. Monitoring Stream Nutrient Concentration Trends in a Mixed-Land-Use Watershed

    Science.gov (United States)

    Zeiger, S. J.; Hubbart, J. A.

    2014-12-01

    Mixed-land use watersheds are often a complex patchwork of forested, agricultural, and urban land-uses where differential land-use mediated non-point source pollution can significantly impact water quality. Stream nitrogen and phosphorus concentrations serve as important variables for quantifying land use effects on non-point source pollution in receiving waters and relative impacts on aquatic biota. The Hinkson Creek Watershed (HCW) is a representative mixed land use urbanizing catchment (231 km2) located in central Missouri, USA. A nested-scale experimental watershed study including five permanent hydroclimate stations was established in 2009 to provide quantitative understanding of multiple land use impacts on nutrient loading. Spectrophotometric analysis was used to quantify total inorganic nitrogen (TIN) and total phosphorus (TP as PO4) regimes. Results (2010 - 2013) indicate average nitrate (NO3-) concentration (mg/l) range of 0.28 to 0.46 mg/l, nitrite (NO2-) range of 0.02 to 0.03 mg/l, ammonia (NH3) ranged from 0.04 to 0.08 mg/l, and TP range of 0.26 to 0.39 mg/l. With n=858, NO3-, NO2-, NH3, and TP concentrations were significantly (CI=95%, p=0.00) higher in the subbasin with the greatest percent cumulative agricultural land use (57%). NH3 and TP concentrations were significantly (CI=95%, p=0.00) higher (with the exception of the agricultural subbasin) in the subbasin with the greatest percent cumulative urban land use (26%). Results from multiple regression analyses showed percent cumulative agricultural and urban land uses accounted for 85% and 96% of the explained variance in TIN loading (CI=95%, p=0.08) and TP loading (CI=95%, p=0.02), respectively, between gauging sites. These results improve understanding of agricultural and urban land use impacts on nutrient concentrations in mixed use watersheds of the Midwest and have implications for nutrient reduction programs in the Mississippi River Basin and hypoxia reductions in the Gulf of Mexico, USA.

  18. [Effects of sub-watershed landscape patterns at the upper reaches of Minjiang River on soil erosion].

    Science.gov (United States)

    Yang, Meng; Li, Xiu-zhen; Yang, Zhao-ping; Hu, Yuan-man; Wen, Qing-chun

    2007-11-01

    Based on GIS, the spatial distribution of soil loss and sediment yield in Heishui and Zhenjiangguan sub-watersheds at the upper reaches of Minjiang River was simulated by using sediment delivery-distribution (SEDD) model, and the effects of land use/cover types on soil erosion and sediment yield were discussed, based on the simulated results and related land use maps. A landscape index named location-weighted landscape contrast index (LCI) was calculated to evaluate the effects of landscape components' spatial distribution, weight, and structure of land use/cover on soil erosion. The results showed the soil erosion modulus varied with land use pattern, and decreased in the order of bare rock > urban/village > rangeland > farmland > shrub > forest. There were no significant differences in sediment yield modules among different land use/covers. In the two sub-watersheds, the spatial distribution of land use/covers on slope tended to decrease the final sediment load at watershed outlet, hut as related to relative elevation, relative distance, and flow length, the spatial distribution tended to increase sediment yield. The two sub-watersheds had different advantages as related to landscape components' spatial distribution, but, when the land use/cover weight was considered, the advantages of Zhenjiangguan sub-watershed increased. If the land use/cover structure was considered in addition, the landscape pattern of Zhenjiangguan subwatershed was better. Therefore, only the three elements, i.e., landscape components' spatial distribution, land use/cover weight, and land use/cover structure, were considered comprehensively, can we get an overall evaluation on the effects of landscape pattern on soil erosion. The calculation of LCI related to slope suggested that this index couldn' t accurately reflect the effects of land use/cover weight and structure on soil erosion, and thus, needed to be modified.

  19. Model My Watershed - A Robust Online App to Enable Citizen Scientists to Model Watershed Hydrology and Water Quality at Regulatory-Level Standards

    Science.gov (United States)

    Daniels, M.; Kerlin, S.; Arscott, D.

    2017-12-01

    Citizen-based watershed monitoring has historically lacked scientific rigor and geographic scope due to limitation in access to watershed-level data and the high level skills and resources required to adequately model watershed dynamics. Public access to watershed information is currently routed through a variety of governmental data portals and often requires advanced geospatial skills to collect and present in useable forms. At the same time, tremendous financial resources are being invested in watershed restoration and management efforts, and often these resources pass through local stakeholder groups such as conservation NGO, watershed interest groups, and local municipalities without extensive hydrologic knowledge or access to sophisticated modeling resources. Even governmental agencies struggle to understand how to best steer or prioritize restoration investments. A new app, Model My Watershed, was built to improve access to watershed data and modeling capabilities in a fast, accessible, free web-app format. Working across the contiguous United States, the Model My Watershed app provides land cover, soils, aerial imagery and relief, watershed delineation, and stream network delineation. Users can model watersheds or areas of interest and create management scenarios to evaluate implementation of land cover changes and best management practice implementation with both hydrologic and water quality outputs that meet TMDL regulatory standards.

  20. Integrating local research watersheds into hydrologic education: Lessons from the Dry Creek Experimental Watershed

    Science.gov (United States)

    McNamara, J. P.; Aishlin, P. S.; Flores, A. N.; Benner, S. G.; Marshall, H. P.; Pierce, J. L.

    2014-12-01

    While a proliferation of instrumented research watersheds and new data sharing technologies has transformed hydrologic research in recent decades, similar advances have not been realized in hydrologic education. Long-standing problems in hydrologic education include discontinuity of hydrologic topics from introductory to advanced courses, inconsistency of content across academic departments, and difficulties in development of laboratory and homework assignments utilizing large time series and spatial data sets. Hydrologic problems are typically not amenable to "back-of-the-chapter" examples. Local, long-term research watersheds offer solutions to these problems. Here, we describe our integration of research and monitoring programs in the Dry Creek Experimental Watershed into undergraduate and graduate hydrology programs at Boise State University. We developed a suite of watershed-based exercises into courses and curriculums using real, tangible datasets from the watershed to teach concepts not amenable to traditional textbook and lecture methods. The aggregation of exercises throughout a course or degree allows for scaffolding of concepts with progressive exposure of advanced concepts throughout a course or degree. The need for exercises of this type is growing as traditional lecture-based classes (passive learning from a local authoritative source) are being replaced with active learning courses that integrate many sources of information through situational factors.