Citizen Participation in Collaborative Watershed Partnerships

Collaborative efforts are increasingly being used to address complex environmental problems, both in the United States and abroad. This is especially true in the growing field of collaborative watershed management, where diverse stakeholders work together to develop and advance water-quality goals. Active citizen participation is viewed as a key component, yet groups often struggle to attract and maintain citizen engagement. This study examined citizen participation behavior in collaborative watershed partnerships by way of a written survey administered to citizen members of 12 collaborative watershed groups in Ohio. Results for the determination of who joins such groups were consistent with the dominant-status model of participation because group members were not demographically representative of the broader community. The dominant-status model, however, does not explain which members are more likely to actively participate in group activities. Instead, individual characteristics, including political activity, knowledge, and comfort in sharing opinions with others, were positively correlated with active participation. In addition, group characteristics, including government-based membership, rural location, perceptions of open communication, perceptions that the group has enough technical support to accomplish its goals, and perceived homogeneity of participant opinions, were positively correlated with active participation. Overall, many group members did not actively participate in group activities.     

Fate and Transport Modeling of Potential Pathogens: The Contribution From Sediments1

Abstract: Escherichia coli was used as a bacterial tracer for the development, calibration, and validation of a watershed scale fate and transport model to be extended to a suite of reference pathogens (Cryptosporidium, Giardia, Campylobacter, E. coli O157:H7). E. coli densities in water and sediments from the Blackstone River Watershed, Massachusetts, were measured at three sites for a total of five wet weather events and three dry weather events covering three seasons. The confirmed E. coli strains were identified by ribotyping for tracking the sources of E. coli and for determining the association of downstream E. coli isolates with isolates from upstream sediments. A large number of downstream samples were associated with upstream sediment sources of E. coli. E. coli densities ranged from 71 to 6,401 MPN/100 ml in water samples and from 2 to 335 MPN/g in sediments. Pearson correlation analysis revealed significant correlations between E. coli and total coliforms in water (r = 0.777, p < 0.01) and sediments (r = 0.728, p < 0.01). In addition, E. coli concentrations in water were weakly correlated with sediment particle size and sediment concentrations (r = 0.298, p < 0.01). A hydrologic model, WATFLOOD/SPL9, was used to predict the temporal and spatial variation of E. coli in the Blackstone River. The rapid rise of stream E. coli densities was more accurately predicted by the model with the inclusion of sediment resuspension, thus demonstrating the importance of the process.     

Linking Hydrologic Alteration to Biological Impairment in Urbanizing Streams of the Puget Lowland,Washington, USA1

Abstract: We used a retrospective approach to identify hydrologic metrics with the greatest potential for ecological relevance for use as resource management tools (i.e., hydrologic indicators) in rapidly urbanizing basins of the Puget Lowland. We proposed four criteria for identifying useful hydrologic indicators: (1) sensitive to urbanization consistent with expected hydrologic response, (2) demonstrate statistically significant trends in urbanizing basins (and not in undeveloped basins), (3) be correlated with measures of biological response to urbanization, and (4) be relatively insensitive to potentially confounding variables like basin area. Data utilized in the analysis included gauged flow and benthic macroinvertebrate data collected at 16 locations in 11 King County stream basins. Fifteen hydrologic metrics were calculated from daily average flow data and the Pacific Northwest Benthic Index of Biological Integrity (B‐IBI) was used to represent the gradient of response of stream macroinvertebrates to urbanization. Urbanization was represented by percent Total Impervious Area (%TIA) and percent urban land cover (%Urban). We found eight hydrologic metrics that were significantly correlated with B‐IBI scores (Low Pulse Count and Duration; High Pulse Count, Duration, and Range; Flow Reversals, T_Qmean, and R‐B Index). Although there appeared to be a great deal of redundancy among these metrics with respect to their response to urbanization, only two of the metrics tested – High Pulse Count and High Pulse Range – best met all four criteria we established for selecting hydrologic indicators. The increase in these high pulse metrics with respect to urbanization is the result of an increase in winter high pulses and the occurrence of high pulse events during summer (increasing the frequency and range of high pulses), when practically none would have occurred prior to development. We performed an initial evaluation of the usefulness of our hydrologic indicators by calculating and comparing hydrologic metrics derived from continuous hydrologic simulations of selected basin management alternatives for Miller Creek, one of the most highly urbanized basins used in our study. We found that the preferred basin management alternative appeared to be effective in restoring some flow metrics close to simulated fully forested conditions (e.g., T_Qmean), but less effective in restoring other metrics such as High Pulse Count and Range. If future research continues to support our hypothesis that the flow regime, particularly High Pulse Count and Range, is an important control of biotic integrity in Puget Lowland streams, it would have significant implications for stormwater management.     

A Tool for Automated Load Duration Curve Creation1

Abstract: A recent study by the Texas Bacteria Total Maximum Daily Load (TMDL) Task Force has recommended the use of load duration curves as a primary tool in calculating bacterial TMDLs. This method is attractive because it effectively integrates flow regimes into TMDL analyses, clearly communicates data through a method that is understandable to the general public, and has been successfully applied in TMDL studies in other states. To ease the creation of load duration curves, an automated load duration curve creation tool called LDCurve has been created within a Microsoft Excel framework. Web services and a webscraper are used to retrieve U.S. Geological Survey streamflow data and Texas Commission on Environmental Quality water quality data. Data are imported to the spreadsheet, combined to create flow and load duration curves, and plotted. Final steps result in a preliminary estimate of the overall load reductions needed to meet water quality standards in the modeled segment. LDCurve is currently only applicable in the state of Texas, but may be updated to model water quality throughout the nation using analogous web services from the EPA STORET database. By using automated data retrievals and computations, the LDCurve tool reduces the amount of time required to create curves and calculate load reductions to a matter of minutes. LDCurve and all supporting materials are available online for free download at: http://tools.crwr.utexas.edu/LDCurve/ .     

The Watershed Deposition Tool: A Tool for Incorporating Atmospheric Deposition in Water‐Quality Analyses1

Abstract: A tool for providing the linkage between air and water‐quality modeling needed for determining the Total Maximum Daily Load (TMDL) and for analyzing related nonpoint‐source impacts on watersheds has been developed. Using gridded output of atmospheric deposition from the Community Multiscale Air Quality (CMAQ) model, the Watershed Deposition Tool (WDT) calculates average per unit area and total deposition to selected watersheds and subwatersheds. CMAQ estimates the wet and dry deposition for all of its gaseous and particulate chemical species, including ozone, sulfur species, nitrogen species, secondary organic aerosols, and hazardous air pollutants at grid scale sizes ranging from 4 to 36 km. An overview of the CMAQ model is provided. The somewhat specialized format of the CMAQ files is not easily imported into standard spatial analysis tools. The WDT provides a graphical user interface that allows users to visualize CMAQ gridded data and perform further analyses on selected watersheds or simply convert CMAQ gridded data to a shapefile for use in other programs. Shapefiles for the 8‐digit (cataloging unit) hydrologic unit code polygons for the United States are provided with the WDT; however, other user‐supplied closed polygons may be used. An example application of the WDT for assessing the contributions of different source categories to deposition estimates, the contributions of wet and dry deposition to total deposition, and the potential reductions in total nitrogen deposition to the Albemarle‐Pamlico basin stemming from future air emissions reductions is used to illustrate the WDT capabilities.     

Climate-induced Changes in Spring Maize Water Requirement in Xiliaohe River Watershed

Xiliaohe River watershed plays an important role in regional and national grain security. With the development of society and economy, water consumption that increased dramatically causes water shortages. Crop water requirement can provide quantitative basis for making regional irrigation scheme. In this study, spring maize water requirement is calculated by using PenmanMonteith formula and spring maize coefficient from May to September at 10 meteorological stations in Xiliaohe River watershed from 1951 to 2005. The variation trend of the spring maize water requirement during the whole growing stage, water requirement in every month, and meteorological influencing factors are obtained by using Mann-Kendall method, and the degree of grey incidence between the water requirement and meteorological influencing factors are shown. The results are the spring maize water requirement during the whole growing stages increases at half of the stations in Xiliaohe River watershed, and are remarkably affected by the water requirement in May. The monthly mean, maximum and minimum air temperature form May to September show an increasing trend in Xiliaohe River watershed in recent 55 years. The monthly mean and minimum air temperature increases notably. The relative humidity, precipitation, wind speed and sunshine show a decreasing trend with variety for different months. The monthly maximum air temperature, wind speed, sunshine and monthly mean air temperature have the highest correlation degree with spring maize water requirement from May to September.     

浏阳河土地利用变化对非点源污染负荷的影响

以红壤丘陵区典型流域——浏阳河流域为研究区域,利用1986、2000、2005年3个时段的土地利用数据,分析土地利用方式的变化,并结合土壤普查图和降雨数据,在RS和GIS的支持下,利用长期水文影响评价(L-THIA)模型,评估区域长期水文响应,采用相似流域的营养盐输出系数估算非点源污染负荷。结果表明,从1986～2005年期间,林地和草地有向城镇、农村居民点用地和农业用地转化的趋势,其中农业用地由13.75%增加到20%左右,城镇用地和农村居民用地分别由原来的1.34%和0.10%变为2.56%和0.80%,期间非点源污染敏感区面积不断扩大,污染负荷不断增加,TN由1986年的675.56 t增加到2005年的1 001.02 t,TP从15.52 t增加到了23.41 t。     

黄土高原沟壑区森林和草地小流域水文行为的比较研究

分析了黄土高原沟壑区森林小流域和自然草地小流域的水文效应,并利用实测资料和模型计算结果比较了两流域的水循环特点,结果发现在郁闭度相同的情况下,森林小流域较自然草地小流域有较小的径流量、较大的蒸散量和较低的３ｍ土层平均含水量,也就是说森林的覆盖增强了水分小循环,削弱了水文大循环,并导致土壤含水量降低。同时也发现森林的上述水文效应仅当其郁闭度达到一定程度时才能表现出来。通过比较两类生态系统植物生长的土壤水分环境条件和水分利用率,认为黄土高原沟壑区在大力发展林业时应以沟谷为主     

Modeling the relationship between land use and surface water quality

It is widely known that watershed hydrology is dependent on many factors, including land use, climate, and soil conditions. But the relative impacts of different types of land use on the surface water are yet to be ascertained and quantified. This research attempted to use a comprehensive approach to examine the hydrologic effects of land use at both a regional and a local scale. Statistical and spatial analyses were employed to examine the statistical and spatial relationships of land use and the flow and water quality in receiving waters on a regional scale in the State of Ohio. Besides, a widely accepted watershed-based water quality assessment tool, the Better Assessment Science Integrating Point and Nonpoint Sources (BASINS), was adopted to model the plausible effects of land use on water quality in a local watershed in the East Fork Little Miami River Basin. The results from the statistical analyses revealed that there was a significant relationship between land use and in-stream water quality, especially for nitrogen, phosphorus and Fecal coliform. The geographic information systems (GIS) spatial analyses identified the watersheds that have high levels of contaminants and percentages of agricultural and urban lands. Furthermore, the hydrologic and water quality modeling showed that agricultural and impervious urban lands produced a much higher level of nitrogen and phosphorus than other land surfaces. From this research, it seems that the approach adopted in this study is comprehensive, covering both the regional and local scales. It also reveals that BASINS is a very useful and reliable tool, capable of characterizing the flow and water quality conditions for the study area under different watershed scales. With little modification, these models should be able to adapt to other watersheds or to simulate other contaminants. They also can be used to study the plausible impacts of global environmental change. In addition, the information on the hydrologic effects of land use is very useful. It can provide guidelines not only for resource managers in restoring our aquatic ecosystems, but also for local planners in devising viable and ecologically-sound watershed development plans, as well as for policy makers in evaluating alternate land management decisions.     

秦淮河流域句容水库农业流域水体沉积物的反硝化作用

2007年5、8、11月和2008年2月,在秦淮河流域句容水库农业流域的河流和水库中,采用自行设计制作的无扰动采样器采集了沉积物柱样,使用乙炔抑制法进行培养试验,并测定了沉积物上覆水的温度(T)、铵态氮(NH4+-N)、硝态氮(NO-3-N)和总溶解性氮(TDN)的浓度,以及沉积物有机质(OM)和全氮(TN)含量,研究了沉积物反硝化潜势的季节变化及其影响因素.结果显示,水体沉积物反硝化潜势存在显著的季节差异,河流沉积物的反硝化潜势范围在8.85～64.04pμg·m-2·h-1之间、水库沉积物的反硝化潜势范围在5.01～28.18μg·m-2·h-1之间.沉积物反硝化潜势的季节变化与上覆水的温度、NH4+-N、NO-3-N和TDN的浓度,及沉积物的OM和TN含量的季节变化有关.