生态理念的尝试—参加国际建协竞赛“建筑与水”有感

从分析生态理念的表达方式入手,结合黄土高原地区的地域性,在“建筑与水”概念性设计竞赛方案中尝试运用生态学研究成果。通过对这一过程的分析,探索生态理念在具体规划设计中的应用模式。     

Rainwater harvesting to alleviate water scarcity in dry conditions: A case study in Faria Catchment, Palestine

In arid and semi-arid regions, the availability of adequate water of appropriate quality has become a limiting factor for development.This paper aims to evaluate the potential for rainwater harvesting in the arid to semi-arid Faria Catchment, in the West Bank, Palestine.Under current conditions, the supply-demand gap is increasing due to the increasing water demands of a growing population with hydrologically limited and uncertain supplies.By 2015, the gap is estimated to reach 4.5×106 m3.This study used the process-oriented and physically-based TRAIN-ZIN model to evaluate two different rainwater harvesting techniques during two rainfall events.The analysis shows that there is a theoretical potential for harvesting an additional 4 × 106 m3 of surface water over the entire catchment.Thus, it is essential to manage the potential available surface water supplies in the catchment to save water for dry periods when the supply-demand gap is comparatively high.Then a valuable contribution to bridging the supply-demand gap can be made.     

A Review of Source Control of Urban Stormwater Runoff1

Stormwater management, based upon techniques located at or close to where rain falls, is reviewed and two categories (at the ground surface and below-ground) are illustrated. The management of stormwater by these source control techniques requires both quantity and quality design criteria to be employed, and for maintenance provision to be clearly in-built. Source control techniques have been studied in projects since the 1980s, and it is suggested that the present emphasis upon sustainable development should encourage their incorporation within environmental/catchment management strategies to assist in addressing a number of identified problems from the uncontrolled discharges of stormwater.     

基于LAI的PM蒸散发计算模型及应用

采用空间分辨率为8 km×8 km、时间分辨率为15 d的美国航空航天局(NASA)全球监测与模型研究组发布的卫星GIMMS/NDVI数据,反演了褒河流域叶面积指数(LAI)的空间分布,引入基于LAI的Penman-Monteith模型,模拟了褒河流域蒸散发能力的时空分布,分析比较了不同植被覆盖下蒸散发能力的变化规律。结果表明:褒河流域植被蒸腾作用强于土壤蒸发,并且不同的植被覆盖对蒸散发能力的大小和时间分布有着显著的影响。     

Determination of nitrogen reduction levels necessary to reach groundwater quality targets in large river basins: the Weser basin case study,Germany

We used the interdisciplinary model network REGFLUD to predict the actual mean nitrate concentration in percolation water at the scale of the Weser river basin (Germany) using an area—differentiated (100 m × 100 m) approach. REGFLUD combines the agro-economic model RAUMIS for estimating nitrogen surpluses and the hydrological models GROWA/DENUZ for assessing the nitrate leaching from the soil. The areas showing predicted nitrate concentrations in percolation water above the EU groundwater quality standard of 50 mg NO₃/l, have been identified as priority areas for implementing nitrogen reduction measures. For these “hot spot” areas a backward modelling approach was used to quantify the maximal permissible nitrogen surplus levels in agriculture to guarantee a mean long-term nitrate concentration in percolation water below 50 mg NO₃/l. Research work will directly support the implementation of the EU-Water Framework Directive in the Weser basin, e.g. by using the maximal permissible nitrogen surplus levels as a framework for the derivation of regionally adapted and hence effective nitrogen reduction measures.     

基于分水岭变换的目标图像的分割与计数方法

针对在图像分析中所获得的目标物体相互粘连的情况,利用分水岭变换的模拟浸水原理,提出了一种新的、有效的分水岭分割算法。算法只需考虑图片中像素的4连通和集水盆地的边缘情况即可,使得粘连物体得到了有效的切割和分离。统计各个所得盆地即可以得到实际物体的准确个数。该分割方法成功有效地解决了目标物体粘连而造成的不便和对后续处理的干扰等问题,同时把该算法用于对粘连物体的计数方面,使本来繁琐、复杂的图像物体计数变得十分简单、便捷。是一种切实可行的图像分割与计数方法。     

Historical pattern of phosphorus loading to Lake Erie watersheds

Phosphorus (P) applied to croplands in excess of crop requirements has resulted in large-scale accumulation of P in soils worldwide, leading to freshwater eutrophication from river runoff that may extend well into the future. However, several studies have reported declines in surplus P inputs to the land in recent decades. To quantify trends in P loading to Lake Erie (LE) watersheds, we estimated net anthropogenic phosphorus inputs (NAPI) to 18 LE watersheds for agricultural census years from 1935 to 2007. NAPI quantifies anthropogenic inputs of P from fertilizer use, atmospheric deposition and detergents, as well as the net exchange in P related to trade in food and feed. Over this 70-year period, NAPI increased to peak values in the 1970s and subsequently declined in 2007 to a level last experienced in 1935. This rise and fall was the result of two trends: a dramatic increase in fertilizer use, which peaked in the 1970s and then declined to about two-thirds of maximum values; and a steady increase in P exported as crops destined for animal feed and energy production. During 1974–2007, riverine phosphorus loads fluctuated, and were correlated with inter-annual variation in water discharge. However, riverine P export did not show consistent temporal trends, nor correlate with temporal trends in NAPI or fertilizer use. The fraction of P inputs exported by rivers appeared to increase sharply after the 1990s, but the cause is unknown. Thus estimates of phosphorus inputs to watersheds provide insight into changing source quantities but may be weak predictors of riverine export.     

Over-parameterised, uncertain 'mathematical marionettes' - how can we best use catchment water quality models? An example of an 80-year catchment-scale nutrient balance

The Integrated Catchment Model of Nitrogen (INCA-N) was applied to the River Lambourn, a Chalk river-system in southern England. The model's abilities to simulate the long-term trend and seasonal patterns in observed stream water nitrate concentrations from 1920 to 2003 were tested. This is the first time a semi-distributed, daily time-step model has been applied to simulate such a long time period and then used to calculate detailed catchment nutrient budgets which span the conversion of pasture to arable during the late 1930s and 1940s. Thus, this work goes beyond source apportionment and looks to demonstrate how such simulations can be used to assess the state of the catchment and develop an understanding of system behaviour. The mass-balance results from 1921, 1922, 1991, 2001 and 2002 are presented and those for 1991 are compared to other modelled and literature values of loads associated with nitrogen soil processes and export. The variations highlighted the problem of comparing modelled fluxes with point measurements but proved useful for identifying the most poorly understood inputs and processes thereby providing an assessment of input data and model structural uncertainty. The modelled terrestrial and instream mass-balances also highlight the importance of the hydrological conditions in pollutant transport. Between 1922 and 2002, increased inputs of nitrogen from fertiliser, livestock and deposition have altered the nitrogen balance with a shift from possible reduction in soil fertility but little environmental impact in 1922, to a situation of nitrogen accumulation in the soil, groundwater and instream biota in 2002. In 1922 and 2002 it was estimated that approximately 2 and 18 kg N ha^− 1 yr^− 1 respectively were exported from the land to the stream. The utility of the approach and further considerations for the best use of models are discussed.     

Agriculture and Water Quality: A Regional Study

Water quality, measured on a fisheries ecosystem scale of 1 (good/salmonid) to 6 (bad/fish absent), of forty-two lowland streams in two Northern Ireland river catchments was inversely correlated with the stocking rate of grazing animals. A decrease in water quality of one class was associated with an increase in the combined grazing/stocking rate of cattle and sheep of 0.6 dairy cow equivalents/ha. This dairy cow equivalent stocking rate was significantly correlated with maximum BOD and total amm.N concentrations and minimum dissolved-oxygen levels. The worst pollution events, with BOD concentrations in excess of 100 mg/1, occurred at the end of May and were caused by discharges of silage effluent. Smaller BOD peaks, which occurred in late winter and early spring, were related to the land spreading of animal slurries. It was concluded that poultry and pig farms were not having a major impact on water quality.     

一种新型防腐涂料在车辆发动机水箱集水槽中的应用

车辆发动机冷却系统中的冷却剂夏季是水,冬季是乙二醇型防冻液,对发动机水箱前、后集水槽钢板普遍腐蚀严重。通过对刮涂SB-99阻尼防腐涂料实车挂片实验,结果证明能使发动机水箱集水槽耐蚀性得到显著提高。