10a生连香树人工群落生物量研究

对１０年（ａ）生连香树人工群落生物量的分布与模型及凋落物进行了研究,主要结果为：①建立了连香树各器官与地（胸）径或树高的回归模型６８个．②群落总生物量（Ｗｔ／ｔｈｍ－２）为１２６．３２６,其中,地上和地下部分生物量（Ｗ／ｔｈｍ－２）分别为７６．０６８和４７．８１０,凋落物Ｗ为２．４４８．③群落、根系和吸收根的生产力（Ｐ／ｔｈｍ－２ａ－１）分别是１２．３８８～１５．２４８、４．７８１和０．６１１．④群落光能和有效光能利用率分别为０．７５％和１．８８％．⑤９７．４８％的根集中于０～２０ｃｍ土层,６９．９３％的根分布于距干基４０ｃｍ的水平范围;９２．０７％的叶分布于３～６ｍ的垂直范围,８３．８０％的叶分布于距干基１ｍ的水平范围;８４．０５％的干枝分布于距干基０．５ｍ的水平范围．⑥１０～１２月凋落量占全年的８１．２６％．⑦凋落物对元素生物循环的影响大小顺序为Ｐ＞Ｎ＞Ｋ＞Ｃａ＞Ｍｇ＞Ｆｅ＞Ａｌ＞Ｍｎ．⑧提出了生物循环功能系数、凋落物分解率和保存率的算法及含义     

农业可持续发展状态评价指标(体系)框架及其分析

通过对农业活动、农业政策与农业环境变化关系的研究,提出了反映农业可持续发展状态的指标结构以及面向农业决策的状态指标分析框架,建议采用“离差法”来评价农业系统的可持续发展状态,其评价结果可以用来判断和制定正确的农业政策;同时还论述了状态评价的具体方法、步骤及评价标准     

淀山湖着生藻类群落结构与数量特征

在１９９３～１９９７－０６间对淀山湖５种沉水植物及人工基质上的着生藻类群落进行了研究。结果表明,沉水植物上着生藻类群落由３７属３９种藻类组成,其中硅藻门１３属１３种,绿藻门１２属１３种,蓝藻门６属７种。５种沉水植物上着生藻类群落密度和生物量,均以黑藻最高,金鱼藻次之,菹草居第３,人工基质（塑料板）介于金鱼藻和菹草之间;并于冬季达全年最高峰,夏季为全年最低。着生藻类生长与沉水植物生长间呈负相关,并限     

WATERSHED AND LAKE WATER QUALITY ASSESSMENT: AN INTEGRATED MODELING APPROACH1

Watershed planning groups and action agencies seek to understand how lake water quality responds to changes in watershed management. This study developed and demonstrated the applicability of an integrated modeling approach for providing this information. An integrated model linking watershed conditions to water-quality of the receiving lake incorporated the following components: (1) an event-based AGNPS model to estimate watershed pollutant losses; (2) annualization of AGNPS results to produce annual lake pollutant loadings; (3) a base flow separation package, SAM, to estimate base flow; (4) estimates of nutrients in base flow and point sources; and (5) linkage of watershed loadings directly to EUTROMOD lake water quality algorithms. Results are presented for Melvern Lake, a 28-km² multipurpose reservoir with a 900-km² agricultural watershed in east central Kansas. Reasonable estimates of current lake quality were attained using an average phosphorus availability factor of 31 percent to calibrate model results to measured in-lake phosphorus. Comparison of a range of possible scenarios, including all cropland changed to no-till (best case) and all CRP and good-condition grasslands changed to cropland (worst case), indicated only a (4 percent change for in-lake phosphorus and a (2 percent change for chlorophyll a. These results indicated that this watershed is not sensitive to projected changes in land use and management.     

POTENTIAL CLIMATE CHANGE IMPACTS ON WATER RESOURCES IN THE GREAT PLAINS1

ABSTRACT: This paper reports on the current assessment of climate impacts on water resources, including aquatic ecosystems, agricultural demands, and water management, in the U.S. Great Plains. Climate change in the region may have profound effects on agricultural users, aquatic ecosystems, and urban and industrial users alike. In the central Great Plains Region, the potential impacts of climate changes include changes in winter snowfall and snow-melt, growing season rainfall amounts and intensities, minimum winter temperature, and summer time average temperature. Specifically, results from general circulation models indicate that both annual average temperatures and total annual precipitation will increase over the region. However, the seasonal patterns are not uniform. The combined effect of these changes in weather patterns and average seasonal climate will affect numerous sectors critical to the economic, social and ecological welfare of this region. Research is needed to better address the current competition among the water needs of agriculture, urban and industrial uses, and natural ecosystems, and then to look at potential changes. These diverse demands on water needs in this region compound the difficulty in managing water use and projecting the impact of climate changes among the various critical sectors in this region.     

基于人工影响天气的气象灾害减灾技术

对全国人工影响天气的气象灾害减灾技术及人工增雨防雹成果进行了归纳总结。提出根据不同气象灾害的特点，采取有针对性的减灾技术措施，并对减灾效益进行评估。通过对近年来我国基于人工影响天气技术的人工增雨防雹等作业范围及其规模、主要作业技术及其与国外的差距、作业区的减灾效益等进行分析，指出我国人工影响天气减灾技术及应用体系有了很大发展，并为减轻气象灾害提供了科学依据。     

生物膜反应器降解生物质气化洗焦废水

陶瓷球作为固定介质 ,接种本实验室保藏的Pseudomonassp1和Pseudomonassp2混合菌种 ,应用生物膜反应器处理生物质气化过程中产生的洗焦废水 ,对反应器运转整个过程的进出水COD浓度、进出水苯、萘、菲、吡啶、喹啉、异喹啉的含量、反应器内和反应器出水含菌量进行测定 ,以了解生物膜反应器处理生物质气化洗焦废水的特性 .结果表明 ,反应器经挂膜、增菌后 ,可达到稳定运转状态 ,有效的控制了反应器内微生物细胞的流失 ,使生物质气化洗焦废水中的有机物得到较好去除 .     

农业非点源控制的美国经验借鉴

我国的农业非点源污染治理正处于攻坚期,但部分政策一定程度上缺少具体执行标准和规范,难以执行到位,法律法规碎片化、分散且难以评估执行效果。本文从美国治理非点源的国际经验出发,梳理了联邦层面的法律法规、农业环境管理机构的运作形式以及州层面流域管理规划和非点源控制计划。最后,根据国际经验提出了如下建议:一是建议要求各省在农业规划中加入推进农业流域治理清单;二是建议制定流域地表水质达标规划,实现点源与非点源联合管理;三是建议形成最佳管理实践规范技术指南,并对执行者进行相应补贴,形成监管机制;四是建议建立农业绿色补贴制度,鼓励地方形成可持续的农业发展机制。     

陆源营养盐输入对青岛近岸海域DMS生物生产的影响

近海海域是全球DMS的重要排放源,同时近海海域,尤其是城市近岸海域是生态环境受人为干扰最为严重的区域.为了解人为活动对DMS生物生产的干扰,以青岛近岸海域为研究区域,在2001～2002年进行了不同季节的采样.发现该区域DMS存在季节变化,在生物量高的夏季,水体的DMS浓度也最高;高营养盐区域DMS/Chl a(单位叶绿素的DMS产量)低;低透明度区域DMS/Chl a也较低,且在长日照的夏季,透明度与DMS/Chl a有显著相关关系.     

于桥水库周边农业小流域氮素流失浓度特征

选择天津市水源地于桥水库周边2个典型的农业小流域进行了长期的氮素流失研究.结果表明,地表径流的总氮浓度以村庄和果园为最高,平均浓度在20 mg·L-1左右;农田次之,山坡最低,平均浓度低于10 mg·L-1.亚表层流中氮素流失在不同地点和不同降雨事件中浓度有较大差异,总体趋势以果园最高,村庄中菜园次之,农田最低.在流域出口处.曹各庄流域地表径流总氮浓度达到18.5 m8·L-1,桃花寺流域出口处浓度为5.9 mg·L-1,流域内不同景观格局和迁移廊道地貌的差异是造成2个流域氮素流失浓度差异的主要原因.曹各庄流域中主要污染源村庄离水库较近(约200 m),且道路型季节性河流等性质特征对污染物的滞留能力较弱,增加了氮素流失到受纳水体的风险;桃花寺流域的污染源村庄和果园离受纳水体较远(约1500 m),氮素在季节性河流迁移过程中被小石坝、植被过滤带和干塘等"汇"型结构所滞留.从而降低了向水体迁移的风险.