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- 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
- 一种改进的ACM算法及其在鄱阳湖水域监测中的应用
- 作者： 冷英 刘忠玲 张衡 王宇 李宁 来源：电子与信息学报 年份：2017 文献类型 ：期刊 关键词： 局部窄带 水域提取 合成孔径雷达 鄱阳湖
- 描述：上述问题,该文提出一种基于局部窄带的ACM边缘提取算法,并将其应用于Sentinel-1A获取的鄱阳湖水域时序观测图像中。该算法首先采用两级Otsu方法获取初始轮廓,随后在初始轮廓附近建立局部窄带
- 全文：上述问题,该文提出一种基于局部窄带的ACM边缘提取算法,并将其应用于Sentinel-1A获取的鄱阳湖水域时序观测图像中。该算法首先采用两级Otsu方法获取初始轮廓,随后在初始轮廓附近建立局部窄带
- 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.