摘要：This study aimed to compare the effects of two types of drip irrigation line design on cotton yield, water use, and net returns. The experiments were carried out in the arid region of Xinjiang, Northwest China, during 2009-2010 growing years. The two types of lateral placement are commonly used by the local farmers in the area： double lines （two laterals controlling four rows） and single line designs （one lateral controlling four rows）. The results indicated that less irrigation water was applied by single line compared with double lines design. This implies that more irrigation water could be saved using single line, by reducing the water consumption of cotton. The emergence rates for double lines were 2 and 6% higher than those for single line design in 2009 and 2010. The seed cotton yields for double lines design were 5.76 and 6.41 Mg ha-1 which were 13 and 9% higher than for single line design in 2009 and 2010, respectively. Single lines could however lower the investment cost compared to double lines, which produced 10 and 7% more net income in 2009 and 2010, respectively. By contrast, the double lines was more profitable and suitable for the farmers in Northwest China than single line design.

摘要：In the Lancang‒Mekong River basin(LMRB),agriculture,dominating the local economy,faces increasing challenges in water supply under climate *** projection of future precipitation in this basin is essential for understanding the *** this study,the Weather Research and Forecasting(WRF)model was applied to project the LMRB *** with the historical period(1986e2005),we analyzed the changes of both the projected precipitation amount and the frequency of rainless(100 mm d
1)for three periods,namely the near-term(2016e2035),mid-term(2046e2065),and long-term(2080e2099).The results indicate that the precipitation amount during the wet season(AprileOctober)is expected to increase in most areas of the basin for the three *** for the precipitation during the dry season(NovembereMarch),an increase is projected in most areas for the near-term,while an increase in the lower reach of the basin and a decrease in the upper and middle reach for the mid-term and *** precipitation reduction is expected to be greatest in Myanmar,Laos,Thailand,and Yunnan province of China for the *** frequency of precipitation in different intensities has prominent regional and temporal *** the wet season,the days of rainless and light rain are expected to decrease in the middle reach,whereas the days of rainstorm and heavy rainstorm *** feature is especially strong in southern Thailand,southern Laos and Cambodia in the near-term and in Laos and Thailand for the mid-term and *** the dry season,there are projected increasing rainless days and decreasing days of precipitation for the other intensities in the middle reach,and opposite in the rest area of the *** projected precipitation changes have potential various impact in different parts of the *** middle re

摘要：城市应急避难所的空间配置一直是灾害防治和城市安全研究领域的热点问题。本文以城市居民尽快地,尽少拥挤地到达满足容纳需求的应急避难所为目标,整合遥感影像数据、高精度人口分布数据、交通路网数据和专家知识等数据,综合运用智能体模型和多准则决策方法,对城市避难所空间配置开展研究。本文设计了三类与应急疏散相关的智能体:政府智能体、避难所智能体和居民智能体,来实现应急疏散的模拟,并根据模拟结果支持应急避难所的空间选址和配置。选址方法上运用了多准则决策方法和权重敏感性分析,在选址高适宜区域内选定避难所的新建方案。以新的避难所空间布局和配置为条件,执行新一轮的应急疏散模拟过程,实现选址的循环优化,从而获得最终的避难所空间配置方案。本文以上海市静安区的应急避难所空间配置分析为案例,生成了该区域应急避难所的详细空间配置方案,该方案能帮助居民在尽少拥挤风险下尽快疏散到附近的避难所。本文提出的方法充实了中国城市避难所选址的相关理论与可操作性的技术基础,为其他地区开展避难所的配置工作提供借鉴与参考。

摘要：在空间多准则决策中,敏感性分析是衡量决策过程中不确定性的重要方法。层次分析法(AHP)是常用的空间多准则决策方法之一,它的决策结果很大程度上受其成对比较矩阵生成的准则权重的影响,如何量化评估这一影响的大小、如何实现空间多准则决策的可视化,一直是其中的难点。本研究在AHP实现空间多准则决策的过程中,利用OAT(One-at-a-Time)方法依次改变成对比较矩阵元素值来调整权重,从而量化地、可视化地表示决策结果对这些元素值改变的敏感程度。这种新方法能够执行自定义范围内的定量化的动态变化分析,测度不同权重分配情况下,空间决策结果的敏感性;通过设计的敏感性分析量化指标评判敏感性的相对强弱,锁定成对比较矩阵中更需斟酌的元素值;并在GIS平台支持下,实现可视化的空间数据统计及分析。本研究还以嘉兴市北部地区的旅游开发适宜性评价作为范例,来说明该分析方法在空间多准则决策中的可行性。案例分析中,通过对五个准则图层以及相关的成对比较矩阵的分析,利用统计表格、模拟结果图和汇总图表等多种形式,确定了矩阵中敏感性最高的元素,并完成了元素值的最终设定。该方法深入浅出地帮助相关决策者和研究人员更好地理解权重敏感性,从而在空间多准则决策过程中降低不确定性,进行更有效的测度。

摘要：【目的】建立合理的评价系统,以期在各种土地利用方案和情景下,方便地实现水土保持环境效应评价、流域水文分析以及水土保持措施对区域水资源影响的定量评价。【方法】以黄土高原多沙粗沙区为例,利用TIME组件平台构建了基于GIS的水土保持应用系统,研究基于.NET Framework的黄土高原多沙粗沙区植被恢复布局及其水文效应评价系统的实现;讨论了GIS在水土保持中的应用、水文计算模型与GIS的集成、植被恢复布局及水文效应评价系统的结构框架、数据库设计和系统功能的实现。【结果】该系统充分利用了GIS强大的空间分析、直观的信息表达功能以及数据的存储、处理功能,能方便、快捷地显示和输出水土保持中的多种信息,并利用文字、地图、控件等多种手段进行信息表达。【结论】基于TIME组件开发的GIS模型系统,能够降低开发难度、缩短开发周期。该系统对于水土保持宏观规划的编制具有一定参考意义。

摘要：利用恩诺沙星和盐酸环丙沙星2种抗生素在不同浓度下对球等鞭金藻进行毒理研究。分别对球等鞭金藻的96EC50、叶绿素和过氧化酶活性进行分析。结果表明,2种抗生素对球等鞭金藻的毒理危害等级分别为高毒和中毒。恩诺沙星浓度对叶绿素和过氧化氢酶活性的抑制影响不大,而盐酸环丙沙星浓度在0～10 mg.L-1范围内对叶绿素和过氧化氢酶活性抑制效果明显,当浓度>10 mg.L-1后抑制效果稳定。