检索结果相关分组
- 模拟研究变化水位和流速条件下鄱阳湖磷释放特征
- 作者： 童亚莉 梁涛 王凌青 李可欣 来源：Journal of Geographical Sciences 年份：2017 文献类型 ：期刊
- 描述：Since the construction of the Three Gorges Dam,the Poyang Lake hydrological characteristics obviously changed.During the impoundment period of the Three Gorges Reservoir,the hydrodynamic factors of Poyang Lake varied.Water level dropped,the velocity decreased and water exchange time lengthened,which changed the release of phosphorous from sediments.In order to investigate how the hydrodynamic factors influence the release of phosphorous from sediments,we used a two-way annular flume device to simulate the release characteristics of phosphorous from sediments under variable water levels and velocities.We found that both water level rising and velocity increasing could enhance the disturbance intensity to sediments,which caused the increase of suspended solids(SS)concentration,total phosphorus(TP)concentration in the overlying water,and the ability that phosphorus released to overlying water from sediments enhanced as well:when overlying water velocity maintained 0.3 m/s,SS concentration increased to 4035.85 mg/L at the water level25 cm which was about 25 times compared to the minimum value and TP concentration in the overlying water also reached the maximum value at the water level 25 cm which was 1.2times that of the value at 10 cm;when water level maintained 15 cm,SS concentration increased to 4363.35 mg/L at the velocity of 0.5 m/s which was about 28 times compared to the value of 0 m/s,and TP concentration in the overlying water increased from 0.11 mg/L to 0.44mg/L.When the water level maintained 15 cm,the phosphorous release rate reached the maximum value of 4.86 mg/(md)at 0.4 m/s.The concentration of total dissolved phosphorous(TDP)and soluble reactive phosphate(SRP)both in overlying water and sediment-water interface were negatively correlated with p H.Using the parabolic equation,the optimum water level at a velocity of 0.3 m/s was calculated to be 0.57 cm,and the optimum velocity at water level of 15 cm was found to be 0.2 m/s.
- 全文：Since the construction of the Three Gorges Dam,the Poyang Lake hydrological characteristics obviously changed.During the impoundment period of the Three Gorges Reservoir,the hydrodynamic factors of Poyang Lake varied.Water level dropped,the velocity decreased and water exchange time lengthened,which changed the release of phosphorous from sediments.In order to investigate how the hydrodynamic factors influence the release of phosphorous from sediments,we used a two-way annular flume device to simulate the release characteristics of phosphorous from sediments under variable water levels and velocities.We found that both water level rising and velocity increasing could enhance the disturbance intensity to sediments,which caused the increase of suspended solids(SS)concentration,total phosphorus(TP)concentration in the overlying water,and the ability that phosphorus released to overlying water from sediments enhanced as well:when overlying water velocity maintained 0.3 m/s,SS concentration increased to 4035.85 mg/L at the water level25 cm which was about 25 times compared to the minimum value and TP concentration in the overlying water also reached the maximum value at the water level 25 cm which was 1.2times that of the value at 10 cm;when water level maintained 15 cm,SS concentration increased to 4363.35 mg/L at the velocity of 0.5 m/s which was about 28 times compared to the value of 0 m/s,and TP concentration in the overlying water increased from 0.11 mg/L to 0.44mg/L.When the water level maintained 15 cm,the phosphorous release rate reached the maximum value of 4.86 mg/(md)at 0.4 m/s.The concentration of total dissolved phosphorous(TDP)and soluble reactive phosphate(SRP)both in overlying water and sediment-water interface were negatively correlated with p H.Using the parabolic equation,the optimum water level at a velocity of 0.3 m/s was calculated to be 0.57 cm,and the optimum velocity at water level of 15 cm was found to be 0.2 m/s.
- 基于DEA 模型的产业结构调整与氨氮排放效率关系的实证研究——以鄱阳湖生态经济区为例
- 作者： 廖桂萱 袁菊红 胡绵好 卢福财 来源：江西师范大学学报(自然科学版) 年份：2017 文献类型 ：期刊 关键词： 数据包络分析 氨氮排放效率 鄱阳湖生态经济区 产业结构调整
- 描述：经济和环境的协调发展已经成为区域发展不可忽视的重要问题,鄱阳湖生态经济区作为国家区域发展战略地区之一,其生态与经济的协调发展就显得至关重要.运用DEA方法对鄱阳湖生态经济区36个县(市、区)2009—2013年间氨氮排放效率及其变化率进行分析.结果显示:各县(市、区)之间氨氮排放效率差异明显,东湖区、西湖区、青云谱区和渝水区等8个县(市、区)氨氮排放效率较高,其他县(市、区)氨氮排放效率中等或低下.Malmquist生产率指数计算显示除了南昌县、余江县、高安市和万年县4个县(市、区)氨氮排放综合效率降低外其余都有所上升或不变.依据主导产业和氨氮排放效率将鄱阳湖生态经济区36个县(市、区)划分为高效率第二产业主导区、中效率第二产业主导区、低效率第二产业主导区等8类区域,并提出产业结构调整的相关建议.
- 全文：经济和环境的协调发展已经成为区域发展不可忽视的重要问题,鄱阳湖生态经济区作为国家区域发展战略地区之一,其生态与经济的协调发展就显得至关重要.运用DEA方法对鄱阳湖生态经济区36个县(市、区)2009—2013年间氨氮排放效率及其变化率进行分析.结果显示:各县(市、区)之间氨氮排放效率差异明显,东湖区、西湖区、青云谱区和渝水区等8个县(市、区)氨氮排放效率较高,其他县(市、区)氨氮排放效率中等或低下.Malmquist生产率指数计算显示除了南昌县、余江县、高安市和万年县4个县(市、区)氨氮排放综合效率降低外其余都有所上升或不变.依据主导产业和氨氮排放效率将鄱阳湖生态经济区36个县(市、区)划分为高效率第二产业主导区、中效率第二产业主导区、低效率第二产业主导区等8类区域,并提出产业结构调整的相关建议.
- 鄱阳湖湿地典型草洲主要植物种群在5 个资源环境梯度上的生态位特征
- 作者： 段后浪 赵安 姚忠 来源：生态与农村环境学报 年份：2017 文献类型 ：期刊 关键词： 鄱阳湖典型湿地 生态位宽度 生态位重叠 植物种群
- 描述：基于鄱阳湖典型湿地恒湖农场茶叶港草洲19个样地(5 m×5 m)95个样方(1 m×1 m)实地调查得到的10种主要植物和高程、土壤pH值、电导率、含水量、有机质含量5个资源环境数据,采用
- 全文：基于鄱阳湖典型湿地恒湖农场茶叶港草洲19个样地(5 m×5 m)95个样方(1 m×1 m)实地调查得到的10种主要植物和高程、土壤pH值、电导率、含水量、有机质含量5个资源环境数据,采用
- 鄱阳湖湿地典型草洲主要植物种群在5 个资源环境梯度上的生态位特征
- 作者： 段后浪 赵安 姚忠 来源：生态与农村环境学报 年份：2017 文献类型 ：期刊 关键词： 鄱阳湖典型湿地 生态位宽度 生态位重叠 植物种群
- 描述：基于鄱阳湖典型湿地恒湖农场茶叶港草洲19个样地(5 m×5 m)95个样方(1 m×1 m)实地调查得到的10种主要植物和高程、土壤pH值、电导率、含水量、有机质含量5个资源环境数据,采用
- 全文：基于鄱阳湖典型湿地恒湖农场茶叶港草洲19个样地(5 m×5 m)95个样方(1 m×1 m)实地调查得到的10种主要植物和高程、土壤pH值、电导率、含水量、有机质含量5个资源环境数据,采用