TROPICAL GEOGRAPHY ›› 2019, Vol. 39 ›› Issue (1): 135-143.

### Effect of Hydrological Projects on Hydrologic Connectivity in the Three Outlets of Southern Jing River

Li Jingbao, He Meng, Lyu Dianqing, Yu Dandan and Yang Bo

1. (College of Resources and Environmental Sciences, Hunan Normal University, Changsha 410081, China)
• Received:2018-09-15 Revised:2018-12-10 Online:2019-01-05 Published:2019-01-05

Abstract:

The aim of this study is to examine the quantitative relationship between hydrological projects and the functions of hydrologic connectivity. This investigation is based on the data of hydrological projects and hydrologic connectivity for 1954, 1975, 1990, 2008 and 2016, using set-pair and correlation analysis to quantitatively evaluate the effect of hydrological projects on hydrologic connectivity in the Southern Jing River. The results show that: 1) the correlation coefficient (R2) between the hydrological projects both inside and outside the region and the rate of cutoff, annual mean runoff and sediment runoff are determined to be above 0.5. This indicates a significant correlation between these factors. 2) The relative main value of the three modules of natural function presents a decreasing trend, especially the functions of material/energy interchange and ecology maintenance, which declined rapidly from an acceptable position to a “poor” level since 1990. The relative main values of the three modules of social function presented different trends. Throughout the study period, the function of flood prevention exhibits an increase while the function of transport and resource utilization shows a decrease. The function of water resource distribution initially decreases prior to 1990 followed by an increase after 1990. 3) The level of both natural function and comprehensive function exhibit a decrease during the period 1954-2008 and this situation did not reverse until 2016 during which a small increase was recognized while the level was still low. The level of social function was also low during 1954-1990. However, a significant increase was observed after 2008 and the level was much higher than that of the natural function.