The French National Agency for Nuclear Waste Management (Andra) conducted a site investiga- tions program within the project of a deep geological disposal of radioactive waste in the Meuse/ Haute-Marne region. The con...The French National Agency for Nuclear Waste Management (Andra) conducted a site investiga- tions program within the project of a deep geological disposal of radioactive waste in the Meuse/ Haute-Marne region. The construction of the tunnel of 5 Km length and the shafts of about 500 m depth to access the repository located in the clay host formation of Callovo-Oxfordian age, will lead to the perturbations of the groundwater flow fields. The prediction of the behaviour of these perturbations is needed to support: 1) the engineering and monitoring operations, and 2) the assessment of the consequences on groundwater resources. A variably-saturated flow model of a local multi-layered aquifer system is developed. It integrates the Oxfordian aquifer (limestone), the Kimmeridgianaquitard (marl) and the Barrois limestone aquifer including the karst conduits network. The variably-saturated flow Richard’s equation is solved with a finite element simulator. Prior to the simulation of the predictive repository impacts, a transient flow model is calibrated with respect to Underground Research Laboratory (URL) construction data. The results are analysed and evaluated by the use of performance measures.展开更多
在2010年植被碳密度空间分布结果的基础上,通过13个环境因子的1377个样点数据,建立径向基函数网络(Radial Basis Function Network,RBFN)模型,对桂西北喀斯特区植被碳密度空间分布的影响因素进行了初步探讨。研究结果显示:对该区植被碳...在2010年植被碳密度空间分布结果的基础上,通过13个环境因子的1377个样点数据,建立径向基函数网络(Radial Basis Function Network,RBFN)模型,对桂西北喀斯特区植被碳密度空间分布的影响因素进行了初步探讨。研究结果显示:对该区植被碳密度空间分布影响最为重要的前4位为地类、森林类型、林种和植被类型4个因子,其标准化重要性分别在50%以上;其次为石漠化程度、腐殖层厚度、面积等级、植被总覆盖度和土层厚度5个因子,其标准化的重要性分别在15%—30%;影响最小的是坡位、坡度、坡向和海拔4个地形因子,其标准化重要性仅2%—11%。研究表明地形因子对植被碳密度空间分布影响有限,更为重要的是土地类型、森林类型、林种和植被类型等可通过人为活动改变的因素,因此生态环境移民、退耕还林等石漠化治理措施对植被碳密度空间分布具有重要影响。展开更多
文摘The French National Agency for Nuclear Waste Management (Andra) conducted a site investiga- tions program within the project of a deep geological disposal of radioactive waste in the Meuse/ Haute-Marne region. The construction of the tunnel of 5 Km length and the shafts of about 500 m depth to access the repository located in the clay host formation of Callovo-Oxfordian age, will lead to the perturbations of the groundwater flow fields. The prediction of the behaviour of these perturbations is needed to support: 1) the engineering and monitoring operations, and 2) the assessment of the consequences on groundwater resources. A variably-saturated flow model of a local multi-layered aquifer system is developed. It integrates the Oxfordian aquifer (limestone), the Kimmeridgianaquitard (marl) and the Barrois limestone aquifer including the karst conduits network. The variably-saturated flow Richard’s equation is solved with a finite element simulator. Prior to the simulation of the predictive repository impacts, a transient flow model is calibrated with respect to Underground Research Laboratory (URL) construction data. The results are analysed and evaluated by the use of performance measures.
文摘在2010年植被碳密度空间分布结果的基础上,通过13个环境因子的1377个样点数据,建立径向基函数网络(Radial Basis Function Network,RBFN)模型,对桂西北喀斯特区植被碳密度空间分布的影响因素进行了初步探讨。研究结果显示:对该区植被碳密度空间分布影响最为重要的前4位为地类、森林类型、林种和植被类型4个因子,其标准化重要性分别在50%以上;其次为石漠化程度、腐殖层厚度、面积等级、植被总覆盖度和土层厚度5个因子,其标准化的重要性分别在15%—30%;影响最小的是坡位、坡度、坡向和海拔4个地形因子,其标准化重要性仅2%—11%。研究表明地形因子对植被碳密度空间分布影响有限,更为重要的是土地类型、森林类型、林种和植被类型等可通过人为活动改变的因素,因此生态环境移民、退耕还林等石漠化治理措施对植被碳密度空间分布具有重要影响。
