雨水塘已广泛用于城市雨洪管理实践中,并成为城市景观的重要组成部分。但作为受纳水体,雨水塘长期暴露于人类活动所造成的压力源中,易表现出生态脆弱性和易损性,雨水塘生态风险评价有助于提高生物多样性的保护与恢复。虽然沉积物质量评...雨水塘已广泛用于城市雨洪管理实践中,并成为城市景观的重要组成部分。但作为受纳水体,雨水塘长期暴露于人类活动所造成的压力源中,易表现出生态脆弱性和易损性,雨水塘生态风险评价有助于提高生物多样性的保护与恢复。虽然沉积物质量评价"三元法"(sediment quality triad,SQT)等多学科综合评价方法已得到广泛应用,但其因参照站位选取问题并不适合于雨水塘生态系统,同时评价结果缺少一致性与特异性。研究提出更科学、有效的综合评价方法用于识别并确定雨水塘的生物状态,对于掌握城市雨水塘处理雨水径流的潜在生态风险具有重要的意义。为此,笔者回顾了城市雨水塘生态风险评价研究进展,从参照站位角度分析了现有基于底栖生物的生物评价法存在的局限性。介绍了2类生态质量功能目标的定义以及寡毛类动物指数法(oligochaete index methodology,OIM)结合其三基元(即OIM-SQT)的综合评价方法,并对该方法在生态质量目标概念框架中的应用前景与研究领域进行了展望,提出应用该方法解决参照站位选取问题并形成标准化的操作规程是未来的重点研究方向。展开更多
The sequence of facets and nodes has a direct influence on the efficiency of access to spherical triangle region quadtree. Based on the labeling schema by Lee, spatial curves both for facets and nodes are proposed and...The sequence of facets and nodes has a direct influence on the efficiency of access to spherical triangle region quadtree. Based on the labeling schema by Lee, spatial curves both for facets and nodes are proposed and the main algorithms for coordinate translation, node Lsequence generation and visiting nodes are presented. In particular,constant time algorithms for generating node Lsequence are advanced by using bit manipulation operations,which can be easily implemented with hardware. In L curve the distance between three nodes of a facet is mostly limited in a range of small value, thus making fast access possible. Though codes of sibling facets are continuous, the difference between codes of some cousins may occasionally be very large and makes the distance of a few facets also very large, thus greatly increasing the mean node distance and the total traversing distance. Therefore an m cluster of nodes is proposed as a basic storage unit fo n cluster, which should store eery shared node in each,and the distance between three nodes of a facet is limited to a controllagle scope.展开更多
文摘雨水塘已广泛用于城市雨洪管理实践中,并成为城市景观的重要组成部分。但作为受纳水体,雨水塘长期暴露于人类活动所造成的压力源中,易表现出生态脆弱性和易损性,雨水塘生态风险评价有助于提高生物多样性的保护与恢复。虽然沉积物质量评价"三元法"(sediment quality triad,SQT)等多学科综合评价方法已得到广泛应用,但其因参照站位选取问题并不适合于雨水塘生态系统,同时评价结果缺少一致性与特异性。研究提出更科学、有效的综合评价方法用于识别并确定雨水塘的生物状态,对于掌握城市雨水塘处理雨水径流的潜在生态风险具有重要的意义。为此,笔者回顾了城市雨水塘生态风险评价研究进展,从参照站位角度分析了现有基于底栖生物的生物评价法存在的局限性。介绍了2类生态质量功能目标的定义以及寡毛类动物指数法(oligochaete index methodology,OIM)结合其三基元(即OIM-SQT)的综合评价方法,并对该方法在生态质量目标概念框架中的应用前景与研究领域进行了展望,提出应用该方法解决参照站位选取问题并形成标准化的操作规程是未来的重点研究方向。
文摘The sequence of facets and nodes has a direct influence on the efficiency of access to spherical triangle region quadtree. Based on the labeling schema by Lee, spatial curves both for facets and nodes are proposed and the main algorithms for coordinate translation, node Lsequence generation and visiting nodes are presented. In particular,constant time algorithms for generating node Lsequence are advanced by using bit manipulation operations,which can be easily implemented with hardware. In L curve the distance between three nodes of a facet is mostly limited in a range of small value, thus making fast access possible. Though codes of sibling facets are continuous, the difference between codes of some cousins may occasionally be very large and makes the distance of a few facets also very large, thus greatly increasing the mean node distance and the total traversing distance. Therefore an m cluster of nodes is proposed as a basic storage unit fo n cluster, which should store eery shared node in each,and the distance between three nodes of a facet is limited to a controllagle scope.
