Anthropogenic and Climatic Factors Differentially Affect Waterbody Area and Connectivity in an Urbanizing Landscape: A Case Study in Zhengzhou, China

Abstract

Urbanization alters the distribution and characteristics of waterbodies, potentially affecting both the habitat availability and connectivity for aquatic wildlife. We used Landsat satellite imagery to observe temporal and spatial changes in open-water habitats in Zhengzhou, a rapidly growing city in central China. We classified open water into six categories: perennial rivers, seasonal rivers and streams, canals, lakes, ponds, and reservoirs. From 1990 to 2020, in 5-year intervals, we identified, counted, and measured the area of each kind of waterbody, and we used a model selection approach with linear regressions to ask which climate and anthropogenic drivers were associated with these changes. We also used Conefor software to examine how these changes affected the landscape connectivity for waterfowl. Over the study period, lakes and canals were the only waterbody types to show statistically significant changes in surface area, increasing by 712% and 236%, respectively. Changes in lakes and canals were positively correlated with the length of water pipeline in the city. The connectivity of waterbodies fluctuated over the same period, mirroring fluctuations in the perennial Yellow River. Ponds contributed very little to landscape connectivity, and the importance of reservoirs decreased over time. Conversely, canals played an increasingly important role in landscape connectivity over time. Counterintuitively, the connectivity of waterbodies increased in the built-up part of the city. Our results show that urbanization can have unexpected effects—both positive and negative—on the connectivity and area of open-water habitats. These effects are likely to be important for waterfowl and other aquatic organisms.

Integrating Hydrological Connectivity in a Process–Response Framework for Restoration and Monitoring Prioritisation of Floodplain Wetlands in the Ramganga Basin, India

“…First, the regions of worst or bad connectivity scenarios match with the presence of diminishing or lost wetlands and vice versa; this demonstrates the direct control of hydrological connectivity on wetland degradation. This direct relation between surface connectivity loss and wetland degradation has also been observed elsewhere in Ganga Basin, e.g., Kaabar Tal [23,27,43], and in the lower Ganga delta region [57], in floodplains of the USA [58], China [59], and Australia [60].…”

Variability of the structure of winter microbial communities in Chelyabinsk lakes

“…Today, vast and expanding urbanization is hazardous to the ecosystem of water bodies (Liu et al, 2021). The rate at which urban areas around cities grow are exceeding the rate of population growth (Li et al, 2021), which worsens the hygienic properties of fresh water and, consequently, human health (Xie et al, 2021).…”