[ Objective] The research aimed to establish SWAT distributed hydrologic model and analyze influence of the climatic change on runoff in Beijiang River basin. [ Method] Beijiang River basin as research object, SWAT mo...[ Objective] The research aimed to establish SWAT distributed hydrologic model and analyze influence of the climatic change on runoff in Beijiang River basin. [ Method] Beijiang River basin as research object, SWAT model was used to simulate runoff in basin. Monthly water flow in Shijiao station from 1961 to 1980 was used to determine model parameter, while monthly water flow from 1981 to 1990 was used to verify. Setting 15 kinds of climate change scenarios, SWAT model was used to simulate influence of the future climatic change on runoff in Beijiang River basin. [Result] Simulated accuracy of the SWAT model was high, and it could be used to simulate runoff in Beijiang River basin. Under the situation of in- variable rainfall, temperature rise made that evaporation capacity increased, and runoff depth decreased. When temperature unchanged, rainfall increase made that evaporation capacity and runoff depth increased somewhat. [ Conclusion] The research could provide reference basis for water re- source management in Beijiang River basin.展开更多
Based on the daily precipitation data between 1965 and 2009 from 18 rainfall stations in Guangdong Beijiang River basin and the definitions of Precipitation Concentration Degree(PCD) and Precipitation Concentration Pe...Based on the daily precipitation data between 1965 and 2009 from 18 rainfall stations in Guangdong Beijiang River basin and the definitions of Precipitation Concentration Degree(PCD) and Precipitation Concentration Period(PCP),the inhomogeneous distribution characteristics of interannual precipitation were analyzed by introducing the spatial distribution of annual mean values,variable coefficients,correlation coefficients between annual precipitation,change trends and composite analysis. The results showed that(1) PCD mainly decreased from south to north in spatial distribution; PCP was earlier in most of north-central basin,but relatively later in southern basin.(2) Annual precipitation would increase if PCD decreased in most of river basin,and annual precipitation would decrease as PCP lagged in southern basin,but the change trend was the opposite in northern basin.(3) PCD and PCP mainly showed insignificant upward trend in the entire basin by Mann-Kendall test.展开更多
7 kinds of probability distribution functions were used to fit extreme rainfall indexes R1d（ the maximum 1-d rainfall in the year） and R5d（ the maximum continuous 5-d rainfall in the year） at 18 observation statio...7 kinds of probability distribution functions were used to fit extreme rainfall indexes R1d（ the maximum 1-d rainfall in the year） and R5d（ the maximum continuous 5-d rainfall in the year） at 18 observation stations of Beijiang River basin,and linear moment method was used to estimate parameters. According to fitting goodness test,the best probability distribution function was determined. On this basis,spatial analysis of design values of R1d and R5d with 50-a and 100-a reappearance periods was conducted. Via further selection,GH Copula was taken as connection function,and R1d-R5d joint probability distribution in the basin was studied. The results showed that R1d or R5d probability with 50-a and 100-a reappearance periods was larger in Wengyuan and Qingyuan,while R1d and R5d co-occurrence probability with 50-a and 100-a reappearance periods was larger in central north region.展开更多
The occurrence of antibiotic resistance genes （ARGs） was investigated and quantified in 20 water samples collected in the Beijiang River, South China. Sulfonamide- and tetracycline-resistant bacteria were present in...The occurrence of antibiotic resistance genes （ARGs） was investigated and quantified in 20 water samples collected in the Beijiang River, South China. Sulfonamide- and tetracycline-resistant bacteria were present in 17 and 14 of the collected 20 samples. For sulfonamide ARGs, sulI and sulII were frequently observed in the Beijiang River. The levels of sulI were higher than sulII （p 〈 0.05）, with the mean values of （1.41 ± 1.12） × 10-2 and （1.58 ± 1.71） × 10-3 copies/16S rDNA, respectively. For tetracycline ARGs, tetG had the highest frequency, 100%, followed by tetA （85%）, tetO （85%）, tetC （70%）, tetX （60%）, tetM （40%） and tetQ （20%）, while tetE and tetS were not detected in all the samples from the Beijiang River. On the other hand, tetC had the highest concentration, ranging from 8.30 × 10-2 to 13.20 copies/16S rDNA. The poor correlation between ARGs and antibiotic concentrations revealed that the self-amplification and persistence of ARGs were the reasons that made ARGs exist in the water environment even though the antibiotic selecting pressure was absent. Because so few field measurements have been conducted for investigating the levels of ARGs in rivers in South China, this study provides an important insight on better understanding the occurrence and spread of ARGs in such an ecosystem.展开更多
为了探究北江丁坝群对鱼类栖息地的影响,以北江干流英德段为研究区域,采用非结构化网格有限体积法(FVCOM),计算了不同流量条件下鲫鱼栖息地加权可利用面积(WUA),得到鱼类最适生态流量值。基于鱼类最适生态流量值开展了丁坝群对流速、水...为了探究北江丁坝群对鱼类栖息地的影响,以北江干流英德段为研究区域,采用非结构化网格有限体积法(FVCOM),计算了不同流量条件下鲫鱼栖息地加权可利用面积(WUA),得到鱼类最适生态流量值。基于鱼类最适生态流量值开展了丁坝群对流速、水深、鱼类栖息地适宜性指数和水力生境多样性变化的影响。结果表明:当上游为最适生态流量350 m 3/s时,丁坝群使得WUA由7.142 km 2降低至5.692 km 2;丁坝群会显著改变河道中心和近岸的流速,导致流速适宜度指数下降,进而降低整个研究区域的栖息地适宜度指数;丁坝群的水位壅高作用有限,最大壅高水深为0.38 m,对水深适宜度指数分布影响较小;在丁坝群作用下,栖息地可接受性高的面积占比由52.151%降至32.271%,降低了鱼类栖息地质量;丁坝群造成水力生境多样性辛普森指数由0.547降至0.529,使得研究区域内的水力生境多样性略微减少。研究成果可为北江鱼类栖息地保护和生态恢复提供参考。展开更多
基金Supported by Open Research Fund Program of State Key Laboratory of Water Resources and Hydropower Engineering Science,China(2010B065)National Natural Science Foundation,China(10972080)Fundamental Research Funds for the Central Universities,SCUT,China (2009ZM0186)
文摘[ Objective] The research aimed to establish SWAT distributed hydrologic model and analyze influence of the climatic change on runoff in Beijiang River basin. [ Method] Beijiang River basin as research object, SWAT model was used to simulate runoff in basin. Monthly water flow in Shijiao station from 1961 to 1980 was used to determine model parameter, while monthly water flow from 1981 to 1990 was used to verify. Setting 15 kinds of climate change scenarios, SWAT model was used to simulate influence of the future climatic change on runoff in Beijiang River basin. [Result] Simulated accuracy of the SWAT model was high, and it could be used to simulate runoff in Beijiang River basin. Under the situation of in- variable rainfall, temperature rise made that evaporation capacity increased, and runoff depth decreased. When temperature unchanged, rainfall increase made that evaporation capacity and runoff depth increased somewhat. [ Conclusion] The research could provide reference basis for water re- source management in Beijiang River basin.
基金Supported by the National Natural Science Fund of China(41571091)the "13th Five-year" Planning Item of Guangdong Philosophy and Social Sciences(GD16CGL10)
文摘Based on the daily precipitation data between 1965 and 2009 from 18 rainfall stations in Guangdong Beijiang River basin and the definitions of Precipitation Concentration Degree(PCD) and Precipitation Concentration Period(PCP),the inhomogeneous distribution characteristics of interannual precipitation were analyzed by introducing the spatial distribution of annual mean values,variable coefficients,correlation coefficients between annual precipitation,change trends and composite analysis. The results showed that(1) PCD mainly decreased from south to north in spatial distribution; PCP was earlier in most of north-central basin,but relatively later in southern basin.(2) Annual precipitation would increase if PCD decreased in most of river basin,and annual precipitation would decrease as PCP lagged in southern basin,but the change trend was the opposite in northern basin.(3) PCD and PCP mainly showed insignificant upward trend in the entire basin by Mann-Kendall test.
基金Supported by the National Natural Science Fund of China(41571091)Youth Fund of Humanistic and Social Sciences of the Ministry of Education of PRC in 2017(17YJCZH114)the "13~(th) Five-year" Planning Item of Guangdong Philosophy and Social Sciences(GD16CGL10)
文摘7 kinds of probability distribution functions were used to fit extreme rainfall indexes R1d（ the maximum 1-d rainfall in the year） and R5d（ the maximum continuous 5-d rainfall in the year） at 18 observation stations of Beijiang River basin,and linear moment method was used to estimate parameters. According to fitting goodness test,the best probability distribution function was determined. On this basis,spatial analysis of design values of R1d and R5d with 50-a and 100-a reappearance periods was conducted. Via further selection,GH Copula was taken as connection function,and R1d-R5d joint probability distribution in the basin was studied. The results showed that R1d or R5d probability with 50-a and 100-a reappearance periods was larger in Wengyuan and Qingyuan,while R1d and R5d co-occurrence probability with 50-a and 100-a reappearance periods was larger in central north region.
基金supported by the National Natural Science Foundation of China (No. 21177162)
文摘The occurrence of antibiotic resistance genes （ARGs） was investigated and quantified in 20 water samples collected in the Beijiang River, South China. Sulfonamide- and tetracycline-resistant bacteria were present in 17 and 14 of the collected 20 samples. For sulfonamide ARGs, sulI and sulII were frequently observed in the Beijiang River. The levels of sulI were higher than sulII （p 〈 0.05）, with the mean values of （1.41 ± 1.12） × 10-2 and （1.58 ± 1.71） × 10-3 copies/16S rDNA, respectively. For tetracycline ARGs, tetG had the highest frequency, 100%, followed by tetA （85%）, tetO （85%）, tetC （70%）, tetX （60%）, tetM （40%） and tetQ （20%）, while tetE and tetS were not detected in all the samples from the Beijiang River. On the other hand, tetC had the highest concentration, ranging from 8.30 × 10-2 to 13.20 copies/16S rDNA. The poor correlation between ARGs and antibiotic concentrations revealed that the self-amplification and persistence of ARGs were the reasons that made ARGs exist in the water environment even though the antibiotic selecting pressure was absent. Because so few field measurements have been conducted for investigating the levels of ARGs in rivers in South China, this study provides an important insight on better understanding the occurrence and spread of ARGs in such an ecosystem.
文摘为了探究北江丁坝群对鱼类栖息地的影响,以北江干流英德段为研究区域,采用非结构化网格有限体积法(FVCOM),计算了不同流量条件下鲫鱼栖息地加权可利用面积(WUA),得到鱼类最适生态流量值。基于鱼类最适生态流量值开展了丁坝群对流速、水深、鱼类栖息地适宜性指数和水力生境多样性变化的影响。结果表明:当上游为最适生态流量350 m 3/s时,丁坝群使得WUA由7.142 km 2降低至5.692 km 2;丁坝群会显著改变河道中心和近岸的流速,导致流速适宜度指数下降,进而降低整个研究区域的栖息地适宜度指数;丁坝群的水位壅高作用有限,最大壅高水深为0.38 m,对水深适宜度指数分布影响较小;在丁坝群作用下,栖息地可接受性高的面积占比由52.151%降至32.271%,降低了鱼类栖息地质量;丁坝群造成水力生境多样性辛普森指数由0.547降至0.529,使得研究区域内的水力生境多样性略微减少。研究成果可为北江鱼类栖息地保护和生态恢复提供参考。
