赣北红壤坡地侵蚀性降雨的特征分析

通过对赣北红壤坡地上为期6 a(2001-2006年)的定点观测,研究确定了该区域侵蚀性降雨的雨量及雨强标准分别为11.20 mm和0.88 mm/h,并建立了降雨侵蚀力因子"R=∑E·I30"的最佳算式;通过降雨侵蚀力的分析计算,该区多年平均侵蚀力为8695.43 J·mm/(m2·h),年内分布上主要集中在夏季;研究中还拟合了该区降雨侵蚀力预报简易算法,结果表明当年降雨总量产生10%的波动时,会导致年降雨侵蚀力总量27%的变化.     

基于GIS的黄土高原水土流失监测站点布设方法研究

在GIS空间分析的基础上,借助领域专家知识归一化各侵蚀因子,对归一化的各侵蚀因子团进行叠加再分类和定量分析计算,为黄土高原地区水土流失监测网络布设的复杂空间决策过程提供辅助决策信息。在充分考虑黄土高原地区已有水土流失监测站、点的基础上,遵循国家有关水土流失监测站、点布设的相关规程规则,采用一级控制性监测点与二级局部监测点相结合的办法共布设监测站点138个。     

Carbon Emission and Low carbon Strategies of Sewage Sludge Treatment

The carbon emission during sewage sludge treatment is an important source of greenhouse gas. For the carbon reduction, the emissions from common treatment technologies are calculated with the mass balance model, then their low carbon degrees are evaluated, and finally the low carbon treatment strategies are put forward for different requirements. The results show that the technologies, such as digestion for methane recovery, incineration or co incineration for power production after drying with industrial waste heat, are the ones with the lowest carbon emission. Their low carbon degrees are 89.6%, 80.3% and 76.6% respectively. In the area where the above technologies cannot be applied, aerobic composting or landfill with aerobic stabilization pretreatment are the effective methods to reduce carbon emission. The low carbon treatment strategy, a new part of sludge treatment strategies, should be applied combining the local economy, technology and social conditions, so that it can meet the different requirements from sanitation to carbon emission reduction.     

快速城市化地区小流域降雨径流污染特征

降雨径流污染对快速城市化地区的水环境安全造成巨大威胁.在对深圳市石岩水库6条入库支流的4次降雨径流事件进行水文水质监测的基础上,选择CODcr、NH3-N、TN、TP、SS和BOD5 6种常见水质测试指标对该区域的降雨径流污染的水质状况、空间差异和初始冲刷效应等基本特征进行了分析.结果表明,研究区降雨径流中耗氧性污染物...     

溶剂萃取与生物降解法联合修复老化石油污染土壤

This study aimed to evaluate the efficacy, practicality and sustainability of a combined approach based on solvent extraction and biodegradation to remediate the soils contaminated with high levels of weathered petroleum hydrocarbons. The soils used in this study were obtained from the Shengli Oilfield in China, which had a long history of contamination with high concentrations of petroleum hydrocarbons. The contaminated soils were washed using a composite organic solvent consisting of hexane and pentane (4:1, v/v) and then bioremediated in microcosms which were bioaugmentated with Bacillus subtilis FQ06 strains and/or rhamnolipid. The optimal solvent extraction conditions were determined as extraction for 20 min at 25 °C with solvent-soil ratio of 6:1 (v/w). On this basis, total petroleum hydrocarbon was decreased from 140 000 to 14 000 mg kg-1, which was further reduced to < 4 000 mg kg-1 by subsequent bioremediation for 132 d. Sustainability assessment of this integrated technology showed its good performance for both short- and long-term effectiveness. Overall the results encouraged its application for remediating contaminated sites especially with high concentration weathered hydrocarbons.     

土壤微生物对增温响应的Meta分析

通过对35例2009-2015年初发表的增温控制试验的96组数据进行Meta分析,研究了土壤微生物对增温的响应模式,结果表明:增温提高了土壤微生物碳(1.4%)、土壤微生物氮(1.7%)和土壤真菌量(3.7%),降低了土壤细菌量(-1.9%);土壤微生物碳的增温响应与试验地年平均降水量和增温幅度显著相关;土壤微生物氮的变化受试验地年均温、年均降水量及增温幅度的影响.     

Impacts of Climate Change on Agriculture and Adaptive Strategies in China

China is the world’s most populous country and a major emitter of greenhouse gases. Consequently, China’s role in climate change has received a great deal of attention, whereas the impact of climate change on China has been largely ignored. Studies on the impacts of climate change on agriculture and adaptation strategies are increasingly becoming major areas of scientific concern. However, the clear warming that has been sounded in China in recent decades has not been matched with a clear assessment of the impact of climate change on China’s water resources and agriculture. In the present study, we review observations on climate change, hydrology, and agriculture in China and relate these observations to likely future changes. We also analyse the adaptive strategies in China’s agriculture.     

California Simulation of Evapotranspiration of Applied Water and Agricultural Energy Use in California

The California Simulation of Evapotranspiration of Applied Water (Cal-SIMETAW) model is a new tool developed by the California Department of Water Resources and the University of California, Davis to perform daily soil water balance and determine crop evapotranspiration (ET c ), evapotranspiration of applied water (ET aw ), and applied water (AW) for use in California water resources planning. ET aw is a seasonal estimate of the water needed to irrigate a crop assuming 100% irrigation efficiency. The model accounts for soils, crop coefficients, rooting depths, seepage, etc. that influence crop water balance. It provides spatial soil and climate information and it uses historical crop and land-use category information to provide seasonal water balance estimates by combinations of detailed analysis unit and county (DAU/County) over California. The result is a large data base of ET c and ET aw that will be used to update information in the new California Water Plan (CWP). The application uses the daily climate data, i.e., maximum (T x ) and minimum (T n ) temperature and precipitation (P cp ), which were derived from monthly USDA-NRCS PRISM data (PRISM Group 2011) and daily US National Climate Data Center (NCDC) climate station data to cover California on a 4 km×4 km change grid spacing. The application uses daily weather data to determine reference evapotranspiration (ET o ), using the Hargreaves-Samani (HS) equation (Hargreaves and Samani 1982, 1985). Because the HS equation is based on temperature only, ET o from the HS equation were compared with CIMIS ET o at the same locations using available CIMIS data to determine correction factors to estimate CIMIS ET o from the HS ET o to account for spatial climate differences. Cal-SIMETAW also employs near real-time reference evapotranspiration (ET o ) information from Spatial CIMIS, which is a model that combines weather station data and remote sensing to provide a grid of ET o information. A second database containing the available soil water holding capacity and soil depth information for all of California was also developed from the USDA-NRCS SSURGO database. The Cal-SIMETAW program also has the ability to generate daily weather data from monthly mean values for use in studying climate change scenarios and their possible impacts on water demand in the state. The key objective of this project is to improve the accuracy of water use estimates for the California Water Plan (CWP), which provides a comprehensive report on water supply, demand, and management in California. In this paper, we will discuss the model and how it determines ET aw for use in water resources planning.     

河北省农村饮用水源水质健康危害的风险度评价

介绍了饮用水水源受到化学致癌物及非致癌性污染物所致的健康危害的风险度计算模型,并应用于河北省地下水水源的饮水途径健康风险评价,分别计算出了各类污染物的风险度。结果表明,地下水中化学致癌物所致的健康危害风险度大约为4.41×10-7～8.26×10-4a-1,30%以上超过国际辐射防护委员会（ICRP）推荐的最大可接受限值5.0×10-5a-1,并远远大于非致癌物所致的风险度（在10-11～10-8a-1之间）,所以,化学致癌物是需要首先控制的污染物质;河北省的化学致癌物所致的健康危害的风险度由大到小顺序为Cr6＋〉As〉Cd,非致癌性污染物所致的风险度大小顺序为F-〉Hg〉Pb〉NO32-〉Mn〉NH3-H〉Fe;研究结果可直接确定河北省各市农村地下饮用水源水质的风险度水平、污染物的主次及治理的优先顺序,有助于河北省地下水资源水质的风险管理。