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- 鄱阳湖流域土地覆被的季节性变化特征研究
- 作者： 汪权方 来源：中国科学院研究生院 年份：2017 文献类型 ：学位论文 关键词： 时序NDVI 季节性变化 土地覆被 SPOT4 鄱阳湖流域 VEGETAION
- 描述：鄱阳湖流域土地覆被的季节性变化特征研究
- 鄱阳湖流域土地覆被的季节性变化特征研究
- 作者： 汪权方 来源：中国科学院研究生院 年份：2017 文献类型 ：学位论文 关键词： 时序NDVI 季节性变化 土地覆被 SPOT4 鄱阳湖流域 VEGETAION
- 描述：鄱阳湖流域土地覆被的季节性变化特征研究
- 鄱阳湖流域土地覆被的季节性变化特征研究
- 作者： 汪权方 来源：中国科学院研究生院 年份：2017 文献类型 ：学位论文 关键词： 时序NDVI 季节性变化 土地覆被 SPOT4 鄱阳湖流域 VEGETAION
- 描述：鄱阳湖流域土地覆被的季节性变化特征研究
- 鄱阳湖枯水期沉积物磷释放特征及对水位变化响应
- 作者： 王悦敏 倪兆奎 冯明雷 刘志刚 王圣瑞 李晓秀 来源：环境科学学报 年份：2017 文献类型 ：期刊 关键词： 释放特征 水位 沉积物 鄱阳湖 磷
- 描述：通过研究鄱阳湖枯水期不同高程沉积物磷释放热力学和动力学特征,试图建立沉积物磷释放与水位间响应关系,进一步揭示由于江湖关系变化导致的水位下降对鄱阳湖沉积物磷释放风险影响.结果表明:(1)鄱阳湖沉积物
- 全文：通过研究鄱阳湖枯水期不同高程沉积物磷释放热力学和动力学特征,试图建立沉积物磷释放与水位间响应关系,进一步揭示由于江湖关系变化导致的水位下降对鄱阳湖沉积物磷释放风险影响.结果表明:(1)鄱阳湖沉积物
- 水位变化对鄱阳湖三角洲分流河道沉积特征的影响
- 作者： 王军 杨勇 张阳 杨保良 蒋龙 邱隆伟 赵俊英 来源：中国石油大学学报(自然科学版) 年份：2017 文献类型 ：期刊 关键词： 沉积特征 鄱阳湖三角洲 水位变化 分流河道
- 描述：选取鄱阳湖赣江中支三角洲平原分流河道和信江三角洲前缘分流河道,采用现代沉积考察、剖面挖掘、粒度分析等方法,就水位变化对分流河道沉积特征的影响进行研究。结果表明:在赣江中支三角洲平原分流河道内发育滞留
- 全文：选取鄱阳湖赣江中支三角洲平原分流河道和信江三角洲前缘分流河道,采用现代沉积考察、剖面挖掘、粒度分析等方法,就水位变化对分流河道沉积特征的影响进行研究。结果表明:在赣江中支三角洲平原分流河道内发育滞留
- 鄱阳湖沙山单叶蔓荆（Ｖｉｔｅｘ ｒｏｔｕｎｄｉｆｏｌｉａ）叶性状沿沙化梯度变化特征
- 作者： 常玲玲 蔡家艳 吴琴 金奇 周红艳 胡启武 来源：中国沙漠 年份：2017 文献类型 ：期刊 关键词： 叶氮 沙山 鄱阳湖 rotundifolia) 叶磷 单叶蔓荆(Vitex 比叶面积
- 描述：1.58~13.14cm2,与湖岸线距离没有显著相关性,不能指示沙化程度对单叶蔓荆的影响。比叶面积81.6~206.3cm2·g-1,种内差异显著(P<0.05);单位质量的叶氮、磷含量分别为16.0
- 全文：1.58~13.14cm2,与湖岸线距离没有显著相关性,不能指示沙化程度对单叶蔓荆的影响。比叶面积81.6~206.3cm2·g-1,种内差异显著(P<0.05);单位质量的叶氮、磷含量分别为16.0
- 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.
- 鄱阳湖生态经济区农村居民点空间格局变化与特征分析
- 作者： 邓金连 李欣 叶长盛 来源：江西农业学报 年份：2017 文献类型 ：期刊 关键词： 空间格局 特征分析 鄱阳湖生态经济区 农村居民点
- 描述：以鄱阳湖生态经济区为例,结合GIS技术,采用核密度、扩展强度、平均斑块面积、紧凑度等方法分析了近20多年来农村居民点的空间格局变化特征和演变过程,希望为农村居民点用地的整理与合理规划、科学有序推进
- 全文：以鄱阳湖生态经济区为例,结合GIS技术,采用核密度、扩展强度、平均斑块面积、紧凑度等方法分析了近20多年来农村居民点的空间格局变化特征和演变过程,希望为农村居民点用地的整理与合理规划、科学有序推进