The scaling of urban surface water abundance and impairment with city size
The scaling of urban surface water abundance and impairment with city size
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DOI：
10.1016/j.geomorph.2017.07.001
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发表时间：
2017-07
期刊：
影响因子：
3.9
通讯作者：
M. Steele
中科院分区：
文献类型：
--
作者：
M. Steele
与非城市景观相比，城市化改变了地表水，但人们对基本的水生生态系统特征（如地表水的丰度和损害）如何随人口规模或区域背景而变化知之甚少。这项研究通过量化美国3520个城市的河流长度、水体面积和受损河流长度，研究了地表水的丰度、规模和受损情况，这些城市的人口从2500万到1800万。使用国家水文数据集和EPA的303（d）列表对河流长度、水体面积和受损河流长度进行了量化。这些指标的规模与人口和城市面积使用单一和分段幂律模型和相关的生物物理因素（降水，地形）和土地覆盖。结果表明，城市河流长度和水体面积的丰度实际上随着城市面积的增加而增加，而人均丰度随着人口规模的增加而减少。相对于人口，受损的河流长度没有增加，直到城市人口> 25，000人，然后与人口成线性比例。生物物理背景和土地覆盖解释了丰度和损害的一些变化。发展强度与流密度和减值，但是，这些关系取决于土地覆盖的方向。当高强度开发占据了当地的海拔高点（+15米）和未开发的土地的海拔低点，受损溪流的百分比小于相反的土地覆盖方向（-15米）或非常平坦的土地。这些结果表明，地表水的丰度和损害在美国相邻城市的城市规模和生物物理环境与土地覆盖强度相互作用的影响。
Urbanization alters surface water compared to nonurban landscapes, yet little is known regarding how basic aquatic ecosystem characteristics, such as the abundance and impairment of surface water, differ with population size or regional context. This study examined the abundance, scaling, and impairment of surface water by quantifying the stream length, water body area, and impaired stream length for 3520 cities in the United States with populations from 2500 to 18 million. Stream length, water body area, and impaired stream length were quantified using the National Hydrography Dataset and the EPA's 303(d) list. These metrics were scaled with population and city area using single and piecewise power-law models and related to biophysical factors (precipitation, topography) and land cover. Results show that abundance of stream length and water body area in cities actually increases with city area; however, the per person abundance decreases with population size. Relative to population, impaired stream length did not increase until city populations were > 25,000 people, then scaled linearly with population. Some variation in abundance and impairment was explained by biophysical context and land cover. Development intensity correlated with stream density and impairment; however, those relationships depended on the orientation of the land covers. When high intensity development occupied the local elevation highs (+ 15 m) and undeveloped land the elevation lows, the percentage of impaired streams was less than the opposite land cover orientation (− 15 m) or very flat land. These results show that surface water abundance and impairment across contiguous US cities are influenced by city size and by biophysical setting interacting with land cover intensity.