Analysing the sensitivity behaviour of two hydrology models

Recently, the New Morris Method has been presented as an effective sensitivity analysis tool for mathematical models. The New Morris Method estimates the sensitivity of an output parameter to a given set of input parameters (first-order effects) and the extent these parameters interact with each other (second-order effects). This method requires the specification of two parameters (runs and resolution) that control the sampling of the output parameter to determine its sensitivity to various inputs. The criteria for these parameters have been set on the analysis of a well-behaved analytical function (see Cropp and Braddock, Reliab. Eng. Syst. Saf. 78:77–83, 2002), which may not be applicable to other physical models that describe complex processes. This paper will investigate the appropriateness of the criteria from (Cropp and Braddock, 2002) and hence the effectiveness of the New Morris Method to determine the sensitivity behaviour of two hydrologic models: the Soil Erosion and Deposition System and Griffith University Representation of Urban Hydrology. In the first case, this paper will separately analyse the sensitivity of an output parameter on a set of input parameters (first- and second-order effects) for each model and discuss the physical meaning of these sensitivities. This will be followed by an investigation into the sampling criteria by exploring the convergence of the sensitivity behaviour for each model as the sampling of the parameter space is increased. By comparing these trends to the convergence behaviour from Cropp and Braddock (2002), we will determine how well the New Morris Method estimates the sensitivity for each model and whether the sampling criteria are appropriate for these models. It will be shown that the New Morris Method can provide additional insight into the functioning of these models, and that, under a different metric, the sensitivity behaviour of these models does converge confirming the sampling criteria set by Cropp and Braddock.     

Assessing the Effects of Atmospheric Ethylene on Epinasty and Tuber Yield of Potato (Solanum Tuberosum L.) Near Polyethylene Manufacturing Plants

A multi-year programme was performed to assess the effects of atmospheric ethylene on potato (Solanum tuberosum L.) in the vicinity of polyethylene manufacturing plants. There was a strong temporal variation of the hourly ethylene concentrations measured close to the sources from 1982 through 1991. Growing seasonal means exceeded 12 g m^–3 ethylene, the threshold for phytotoxic effects under laboratory conditions. Young test plants of potato showed an epinastic response to enhanced levels of ethylene. This response was reversible and did not occur when atmospheric ethylene was not detected. Based on hourly observations for the growing seasons of 1984 through 1991, epinasty occurred on average during circa 5% of the growing season and varied from circa 1% in 1985 to circa 18% in 1991. At night, ethylene concentrations were higher and epinasty was more frequent than during daylight hours. The intermittent exposures to ethylene did not affect tuber yield for the growing seasons of 1982 through 1990. The occurrence of epinasty indicated that ethylene exposure levels in the vicinity of the industrial sources might be sufficiently high to affect sensitive plants.     

中国水环境的NPSP问题及对策

介绍了我国水环境中的非点源污染（ＮｏｎｐｏｉｎｔＳｏｕｒｃｅｐｏｌｌｕｔｉｏｎ，缩写为ＮＰＳＰ）的情况，强调农业生产是最主要的非点源污染。同时，针对我国水污染防治的政策目标，提出一些建议。     

Soil properties and crop productivity as influenced by flyash incorporation in soil

Field experiments were carried out during 1996–97at Gulawathi, Muthiani and Salarpur Villages, IARI Farm, NewDelhi and NCPP Campus, Dadri to evaluate changes in soilcharacteristics and growth of wheat (Triticum aestivum L.),mustard (Brassica juncea L.), lentil (Lence esculentaMoench.), rice (Oryza sativa L.) and maize (Zea mays L.) byvarying amounts of flyash addition (up to 50t ha^-1) in soils atsowing/transplanting time of crops. Flyash addition in areasadjoining NCPP Thermal Power Plant, Dadri, Ghaziabad, U.P.ranged from 5–12 t ha^-1 yr^-1 in 1995–96. Shoot and root growthand yield of test crops at different locations after flyashincorporation resulted in beneficial effects of flyashaddition in most cases. The silt dominant texture of flyashimproved loamy sand to sandy loam textures of the surfacesoils at the farmers' fields. The increased growth in yield ofcrops with flyash incorporation was possibly due tomodifications in soil moisture retention and transmissioncharacteristics, bulk density, physico-chemical characterssuch as pH and EC and organic carbon content. The response offlyash addition in the soil on soil health and cropproductivity needs to be evaluated on long-term sustainableaspects.     

Geostatistical Uncertainty Modelling for the Environmental Hazard Assessment During Single Erosive Rainstorm Events

This paper presents an environmental hazard assessment to account the impacts of single rainstorm variability on river-torrential landscape identified as potentially vulnerable mainly to erosional soil degradation processes. An algorithm for the characterisation of this impact, called Erosive Hazard Index (EHI), is developed with a less expensive methodology. In EHI modelling, we assume that the river-torrential system has adapted to the natural hydrological regime, and a sudden fluctuation in this regime, especially those exceeding thresholds for an acceptable range of flexibility, may have disastrous consequences for the mountain environment. The hazard analysis links key rainstorm energy variables expressed as a single-storm erosion index (EI_sto), with impact thresholds identified using an intensity pattern model. Afterwards, the conditional probabilities of exceeding these thresholds are spatially assessed using non-parametric geostatistical techinques, known as indicator kriging. The approach was applied to a test site in river-torrential landscape of the Southern Italy (Benevento province) for 13 November 1997 rainstorm event.     

水蚀风蚀交错带小流域生态环境综合治理模式研究

水蚀风蚀交错带是黄土高原侵蚀最严重的地区和黄河下游河床粗泥沙的主要来源区，其生态环境脆弱、治理难度大，加之晋陕蒙能源基地的大规模开发，也带来了新的环境问题。鉴于治黄和煤田开发及生态环境整治的紧迫需要，以水蚀风蚀交错带六道沟小流域为试区，分析研究了该区水蚀风蚀时空分布规律及脆弱生态环境特征，提出以防治水蚀和风蚀为中心，以提高生态经济效益和持续发展为目标，以基本农田优化结构和高效利用及植被建设为重点，建立具有防蚀固沙兼高效生态经济功能的大农业复合生态系统综合治理模式，取得了良好的社会与经济效益。     

小麦产量的遥感动态预估研究──以山东禹城县为例

本文利用现代遥感信息、数理统计和回归分析方法，研究了禹城县试验区的小麦单产与卫星遥感信息（绿度）间的关系，并建立了小麦单产与绿度关系的预估模型；阐述了直接利用遥感宏观信息动态预估小麦产量的可行性和这一方法的应用前景。     

京津风沙源区防风固沙功能的时空变化及其区域差异

防风固沙功能是京津风沙源治理成效的关键监测指标。以往研究注重局地防风固沙功能的评估,对全区防风固沙功能的时空变化与内部差异揭示不足。基于京津风沙源区多期遥感数据,采用修正风蚀方程与GIS空间统计技术,评估分析了2000-2015年防风固沙功能的整体变化及其区域差异。结果表明:(1)京津风沙源区年均防风固沙量为28.98亿t,防风固沙能力为68.24 t/hm~2,且均随年份变化波动增加,年均增速分别为1.10%和0.71%;(2)京津风沙源区防风固沙能力呈西北高、东南低趋势,有49.06%的区域防风固沙能力高于70 t/hm~2,评估期内有54%的区域防风固沙能力明显提高;(3)浑善达克沙地亚区、典型草原亚区和荒漠草原亚区的防风固沙量累计为全区防风固沙总量的88%,燕山丘陵山地水源保护亚区和晋北山地丘陵亚区的防风固沙能力提升最显著;(4)锡林郭勒盟、赤峰市和乌兰察布市的防风固沙量合计占全区防风固沙量的77%,朔州市与包头市防风固沙能力较高,北京市与天津市防风固沙能力增速较高。因此,未来应重视分区施策治理与西部和北部防风固沙功能提升。     

基于3S的玉溪市土壤侵蚀敏感性评价研究

以玉溪市为研究区域，运用GIS软件对影响土壤侵蚀的因子进行叠加分析，获取玉溪市土壤侵蚀敏感性等级分布图，并与土壤侵蚀现状图加以对比，结果显示：发生土壤侵蚀的地区一定是土壤侵蚀的敏感地区，但土壤侵蚀的敏感地区不一定发生土壤侵蚀：森林覆盖量、质量和人为活动是影响土壤侵蚀的主要原因。     

西北地区高速公路建设中的水土保持

就西北地区高速公路建设的水土流失特点进行了分析，并提出了工程防范措施。