Watershed-based management strategies for the prevention and abatement of polluted agricultural runoff

An increase in the average size of individual livestock production operations coupled with local and regional concentrations of these operations tend to increase negative environmental impacts in many watersheds. Environmental compliance strategies developed by the Texas Institute for Applied Environmental Research (TIAER) can be applied to reduce the negative impacts caused by livestock production and other types of agricultural activities. Further, the Institute's planned intervention/micro-watershed approach may provide the foundation for comprehensive solutions to environmental problems within a broad ecosystem management context.     

The impact of stormwater treatment areas and agricultural best management practices on water quality in the Everglades Protection Area

Half of the original Everglades system has been lost to drainage and development. What remains is included within the boundaries of the Everglades Protection Area (EPA), comprised of three Water Conservation Areas (WCAs) and Everglades National Park (Park). Inflows to the EPA contain elevated nutrient concentrations. Best management practices (BMPs) were implemented and six large wetlands called stormwater treatment areas (STAs) were constructed to improve water quality. We analyzed water quality in the WCAs and Park and performed an economic analysis of the STAs to remove nutrients from EPA inflows. In general, nutrient concentrations in all WCAs were higher during the pre-STA period than after the STAs became operational. In WCA2 and the Park, total phosphorus (TP) trends showed more negative slopes prior, as compared to after, the STAs became operational. These results suggest that BMPs lead to large initial decreases in nutrient export resulting in improved downstream water quality. A preliminary economic analysis shows that operation and management of the STAs are complicated and cost intensive. Comparing the cost of phosphorus (P) removal from water entering the EPA using BMPs and STAs may not currently be viable. BMPs prevent P from being applied to, or leaving from agricultural fields while STAs remove P from stormwater. We expect nutrient concentrations in water flowing into and out of the STAs to decline as both BMPs and STAs become more effective. We suggest an economic analysis of BMPs, STAs, and other potential approaches to determine the most cost-effective methods to reduce nutrient concentrations and related stressors affecting the Everglades.     

Optimal strategies for best management practice placement in a synthetic watershed

It is significant to arrange suitable design and placement of best management practices (BMPs) for reaching the aim that can not only satisfy environmental quality standards, but also decrease the total cost of BMPs. This study applied WinVAST model to predict watershed responses. The objective of this work was to discuss both the economic costs and benefits of BMPs and the control efficiency of discharge and pollutant exports, and to create some suitable standards for the optimal BMPs placement strategies. It is significant to find an optimal number and location of BMPs. In the case study herein, the number of BMPs including a detention pond and a grassy swale would be better to be given by four. The number of BMPs should also be determined by the environmental standards. Moreover, the result shows that the optimal location of BMPs placement is in the downstream area near the outlet and on the mainstream of the catchment. When the BMPs are set in these regions, it cannot only reduce the peak flow and peak pollutant exports, but also have slow time to peak watershed responses.     

The placement strategies of structural best management practices for different moving rainstorms

Hydrological responses and pollutant exports are always highly related to rainfall characteristics. Many studies have demonstrated that the influence of moving rainstorm on flows and mass transport process in hydrologic systems cannot be ignored. Best management practices (BMPs) are popularly applied for controlling water quantity and water quality in a watershed. Since the movements of rainstorm can influence watershed responses, BMP placement strategies should be suitably adjusted in different moving rainstorms. This study designed an intermediate rainfall pattern with varied movement behavior and tried to find the optimal BMP placement strategies, which cannot only satisfy environmental standards but also improve economic benefits, for the rainfall events. The result shows that the control efficiency of pollutant and runoff can highly improve when the BMPs are set near the outlet of a watershed. Since the economic efficiency is always regarded as an important factor, the BMP placement strategy is significant for watershed conservation and management.     

伊犁地区生物多样性保护及利用

伊犁地区是新疆多种多样动植物的分布中心,堪称自然宝库、天生的博物园。由于人类活动的不断加剧、物种资源过度开发利用、森林的破坏与片段化、水域污染等原因,使生物多样性受到威胁。本文通过对伊犁地区生物多样性保护现状和存在问题的分析,提出相应的保护对策及建议。     

Groundwater modeling of Saq Aquifer Buraydah Al Qassim for better water management strategies

Saudi Arabia is an arid country. It has limited water supplies. About 80?C90% of water supplies come from groundwater, which is depleting day by day. It needs appropriate management. This paper has investigated groundwater modeling of Saq Aquifer in Buraydah Al Qassim to estimate the impact of its excessive use on depletion of Saq Aquifer. MODFLOW model has been used in this study. Data regarding the aquifer parameters was measured by pumping tests. Groundwater levels and discharge of wells in the area for the year 2008 and previous record of year 1999 have been collected from Municipal Authority of Buraydah. Location of wells was determined by Garmin. The model has been run for different sets of pumping rates to recommend an optimal use of groundwater resources and get prolonged life of aquifer. Simulations have been made for a long future period of 27?years (2008?C2035). Model results concluded that pumping from the Saq Aquifer in Buraydah area will result into significant cones of depression if the existing excessive pumping rates prevail. A drawdown up to 28?m was encountered for model run for 27?years for existing rates of pumping. Aquifer withdrawals and drawdowns will be optimal with the conservation alternative. The management scheme has been recommended to be adopted for the future protection of groundwater resources in Kingdom of Saudi Arabia.     

Determining the global significance of local and regional mitigation strategies: Setting the scene with global integrated assessment models

Because of the importance and complexity of the processes involved in the response of land cover and land use to changing environmental conditions, other approaches are required to evaluate the effectiveness of mitigation options. One such approach is provided by the global integrated assessment model, IMAGE 2. This article presents the structure and some of the underlying assumptions of IMAGE 2, which illustrates the importance of feedback processes in evaluating the effectiveness of mitigation options with respect to land use. Although models such as IMAGE 2 are unsuitable for local and national mitigation evaluations, they can be used to define the regional and global constraints of the smaller scale assessments.     

Modeling biogeochemistry and forest management practices for assessing GHGs mitigation strategies in forested wetlands

Despite the importance of forested wetland in the global carbon cycle, no widely applicable ecosystem model exists for this ecosystem. This study reports the linkage between Wetland-DNDC and MIKE SHE for carbon dynamics and GHGs mitigation strategies analyses in forested wetland. Wetland-DNDC was modified by parameterizing forest management practices and refining anaerobic biogeochemical processes. Mortality due to senescence was estimated as a function of tree age or as a function of the relative biomass. We used a harvesting damage mortality coefficient as a linear function of time with three parameters: Initial mortality, Duration of the damage and Intensity of the initial harvesting. The model was validated against experimental data obtained from the GNF site near Florida. As a preliminary application, we simulated the effect of water table position and forest management practices on GHGs emissions and carbon dynamics to test the capabilities of the models for simulating seasonal and long-term carbon budget in forested wetland.     

泰州市生态红线区域划分及保护

从泰州市实际出发,阐述了泰州市生态红线区域的划分方法及保护、补偿措施,讨论了生态红线区域保护存在的问题及原因,并从加快规划编制、加快经济发展方式转型升级、加大投入与宣传教育力度等方面,提出对推进生态红线区域保护的思考。     

罗布泊野骆驼国家级自然保护区水环境概况及其保护

罗布泊野骆驼国家级自然保护区水源十分缺乏,基本无地表水系,水源主要以泉水形式存在。目前保护区内分布的泉水点有40多个,泉水点主要分布在保护区东部阿奇克谷地区域和南部阿尔金山区,北部的库鲁克塔格山区也有少量分布。本文介绍了保护区的自然地理环境、水文条件、泉水点分布情况、水质情况及矿产开发、非法放牧及道路建设等人类活动对水源的影响,并提出了水环境保护的意见和措施。     

浅谈生态保护红线区生态系统管理研究概念框架

简述了生态保护红线管理制度的探索实践。提出了生态系统管理的概念框架,包括范围划定、管控分级、目标设定、动态监测、综合分析、管理策略和反馈优化7个方面;识别了生态系统管理中存在的3个关键问题:概念界定、管理方式和保障制度。指出生态保护红线是重点生态功能区、生态环境敏感区和脆弱区等区域划定的严格管控边界,是国家和区域生态安全的底线。要在分析区域生态系统的承载力的基础上,识别重要生态功能区域,进一步辨析生态保护红线的概念;应构建国家层面的生态系统管理方式,以利于红线区管理的整体性;要健全奖惩和补偿机制,引导公众参与生态保护红线的划定、管理和监督工作。     

Determining the Causes of Benthic Condition

A benthic index for northern Gulf of Mexico estuaries has been developed and successfully validated by the Environmental Monitoring and Assessment Program for Estuaries (EMAP-E) in the Louisianian Province. The benthic index is a useful and valid indicator of estuarine condition that is intended to provide environmental managers with a simple tool for assessing the ecological condition of benthic macroinvertebrate communities. Associations between the benthic index and indicators of hypoxia, sediment contamination, and sediment toxicity were investigated to determine the most probable cause(s) of degraded benthic condition. The results showed that, on a local scale, the associations between the benthic index and potential environmental causes differed among estuaries. In Pensacola Bay, FL, for example, there was a significant association between the levels of toxic chemicals (e.g. DDT, silver, and TBT) in the sediment and the benthic index, especially in the bayous which have known sediment contamination problems. In Mobile Bay, however, degraded benthic communities were more closely associated with eutrophication and hypoxia. Nevertheless, a benthic index is a valuable tool for identifying areas that could be already degraded and tracking the status of environmental condition in large geographical regions.     

Determining Ecoregions for Environmental and GMO Monitoring Networks

A representative environmental monitoring network at the regional scale cannot use raster-based or random sampling designs, but requires a stratified sampling procedure integrating different information layers, and it has to occur in ecologically differing homogeneous regions (ecoregions). These we have determined using a set of spatial strata with ecological variables which we analysed with classification and regression trees (CART). We present a framework for environmental monitoring, that covers different scales, and we transfer the framework to a potential GMO (genetically modified organisms) monitoring network. We use ecoregion and other environmental strata together with existing environmental monitoring networks to determine GMO monitoring sites more precisely.     

生态保护区域饮用水源地水质金属健康风险评价

选择重庆市生态保护发展区域饮用水源地为研究对象,运用健康风险评价模型对其水质金属进行评价。结果表明:7个饮用水源地中27种金属元素均达到USEPA、WHO和《生活饮用水卫生标准》(GB 5749—2006)限值要求。饮用水源地中致癌健康风险从高到低依次为CrAsCd,均低于USEPA最大可接受风险。非致癌金属的健康风险从高到低依次为SrPbMoFeCuSeAgNiZnMn,非致癌风险水平为9.36×10~(-11)a~(-1)~1.25×10~(-7)a~(-1),远低于USEPA、ICRP等权威机构限值。成人致癌和非致癌健康风险水平均为女男,致癌总风险均大于非致癌总风险2个数量级以上,总健康风险均保持在10-5数量级水平。     

水杨酸-次氯酸盐测定水中氨氮方法的改进

指出文献[1]法中水杨酸-次氯酸盐法测定氨氮时,生成物的颜色并不是蓝色化合物,而是绿色化合物。提出对水杨酸-次氯酸盐法测定氨氮方法的改进,并通过对亚硝基铁氰化钠和次氯酸钠两溶液的用量、pH值的调试等一系列试验研究与探讨,结果表明,当亚硝基铁氰化钠溶液和次氯酸钠溶液的用量分别为0．20ml和0．10ml时,显色颜色为蓝色。尤其是当显色溶液的pH值在11．60-11．62之间,溶液吸光值尤为稳定。     

豫东黄河故道湿地鸟类自然保护区现状调查及生态保护规划

对豫东黄河故道湿地鸟类自然保护区现状进行了调查,并提出了生态保护规划。     

Three years monitoring survey of pesticide residues in Sardinia wines following integrated pest management strategies

This paper reports the results of a pesticide monitoring survey on wine grapes from the 2008–2010 vintage from vineyards grown according to integrated pest management strategies. A multi-residue gas chromatography-mass spectrometry method in electron ionization and chemical ionization mode has been used for the determination of 30 pesticides in wine samples. The analytical method showed good recoveries and allowed a good separation of the selected pesticides. Repeatability and intermediate precision showed good results with CV?<?20 %. The instrumental method limits of determination (LOD) and of quantification (LOQ) were below the maximum residue levels set in wine. The analysis of the wines showed that pesticide residues were below the instrumental LOQ, and most of them were undetectable (<LOD). Only the 38 % of the pesticide applied has been detected in at least one cultivar. Metalaxil, myclobutanil, and penconazole were the pesticides most frequently found, while carignano and vermentino were the cultivars with the higher number of residues.     

Exposure estimates for the Houston Area Asthma Study

Procedures for determining exposure extimates for the Houston Area Asthma Study are discussed. Two residential clusters of asthmatics in the Houston area have been studied as part of an overall attempt to assess the health effects of air pollution in the Texas Gulf Coast area. Air pollutant exposure data have been produced according to a three-tier monitoring scheme, i.e. (1) continuous data from centrally-located fixed stations, (2) residential indoor/outdoor measurements, and (3) personal monitoring. This air monitoring network should yield estimates of individual exposures for use in health effect correlations.The fixed sites and mobile continuously monitor ambient levels of ozone, nitrogen oxides, sulfur dioxide, carbon monoxide, and meteorological parameters (wind speed, wind direction, temperature, dew point, solar irradiation, and precipitation). Continuous sequential integrated sampling is preformed for total suspended particulates (TSP) and, inhalable particulates (IP) (total of < 2.5m and 2.5–15.0 m) by dichotomous samplers for 24 hr samplers), aldehydes (bubblers), and aeroallergens (intermittent rotorod samplers). In addition to gravimetric determinations, particulate filters are routinely analyzed for sulfate, nitrate, and (every third day) trace elements. Personal monitoring includes ozone, respirable particles, nitrogen dioxide and formaldehyde. A quality assurance/control program that meets specifications established in the EPA Quality Assurance Handbook for air pollution measurement systems was implemented. Examples of results consisting of unvalidated preliminary data from the monitoring for ozone for three participants is presented and approaches to determining exposure estimates are discussed for both an integrated exposure estimate and short time period exposure estimate.(These studies have been funded by the U.S. Environmental Protection Agency through Cooperative Agreement CR 807108010 and Grant R 808738010. Statements made in this article should not be taken as Agency policy.)     

医用电子直线加速器室辐射屏蔽防护设计

在满足《电离辐射防护与辐射安全基本标准》（GB18871—2002）的同时,合理设计医用加速器室的辐射屏蔽防护。以《电离辐射防护与辐射安全基本标准》（GB18871—2002）为准则,运用电离辐射屏蔽原理、计算方法,根据安装的医用加速器所具有的辐射物理特点和辐射防护的发展需求,对所有产生的射线进行严谨、规范和优化的屏蔽计算。结果表明,辐射屏蔽防护符合我国医用加速器机房使用标准。