Water supply services(WSSs) are critical for the regional water balance and water circulation, but relevant studies have not established the relationship between WSSs and human well-being. This research identifies the...Water supply services(WSSs) are critical for the regional water balance and water circulation, but relevant studies have not established the relationship between WSSs and human well-being. This research identifies the scope of areas that benefit from WSSs from an ecosystem service flow perspective. Moreover, the path and quantity of the flow of WSSs are simulated to provide a scientific theoretical basis for ecosystem service management and ecological compensation. The Dongjiang Lake Basin is a national priority river basin in China where ecological compensation pilot programmes concerning water resources are top priorities. Dongjiang Lake Basin experienced an increase and then a decrease in the overall supply of water, with an average net water supply of 1096–1500 mm for the years 1995, 2000, 2005 and 2010. The water demand increased each year in service beneficiary areas(SBAs), varying from 387 to 580 mm. Overall, Dongjiang Lake Basin met the net water demands of the actual SBAs in the lower reaches, but a gap in the water supply and demand emerged gradually. This research provides an understanding of the functional mechanisms for the provision, demand and flow of WSSs and provides a scientific theoretical basis for ecosystem service management and ecological compensation.展开更多
Layer LJ3 of Linjiang stratigraphic section in Dongjiang River valley in the south of the Nanling Mountains is a set of red sandy sediments.Measured by thermoluminescence(TL) dating,it was found to be formed in MIS2-9...Layer LJ3 of Linjiang stratigraphic section in Dongjiang River valley in the south of the Nanling Mountains is a set of red sandy sediments.Measured by thermoluminescence(TL) dating,it was found to be formed in MIS2-9,500 ± 800 yr to 19,600 ± 1,800 yr B.P.After analy-sis of the grain sizes of the 16 samples(LJ3-100 to LJ3-85) in this layer,it was discovered that(1) The contents of each grain group in dif-ferent samples are similar.(2) The values of Md,Mz,,Sk,and Kg vary from LJ3-100 to LJ3-85 in a narrow range.(3) The segments of each sample in the accumulative curves extend parallel with similar slopes.All the three aspects reveal the Aeolian characteristics of Layer LJ3.Therefore,it is thought that Layer LJ3 consists of red sandy sediments formed in MIS2 in the south of Nanling Mountain,which reflects the arid climate at that time.展开更多
On the background of analysis on region water environment safety in the Dongjiang Lake of south-central China, the source of pollution of water environment and its control are studied. The concept of region environmen...On the background of analysis on region water environment safety in the Dongjiang Lake of south-central China, the source of pollution of water environment and its control are studied. The concept of region environment disaster chain is put forward on the basis of combination study on the disaster chain theory and pollution problem in regional water environment. Through identification and analysis of pollution disaster resources in regional water environment of the Dongjiang Lake, the annual emission of the chemical oxygen demand (COD), ammonia nitrogen, total phosphorus (TP) and heavy metal (Cd, As, Pb) are counted. According to evaluation on structure proportion of contaminants in the Dongjiang Lake, agricultural non-point source is the uppermost pollution source, which accounted for 87.74% in total pollution load. Ammonia nitrogen, TP and COD are mainly contaminants accounted for 94.27% in total pollution load. By analyzing danger of contaminants in the lake, basic form of disaster chain of water environment pollution is built elementarily. It shows characteristics of branches and trunk basin disaster chain and embodies multisource disaster implication chain caused by human activities. Then, disaster resources chain-cutting methods for pollution prevention and control of regional water environment of the Dongjiang Lake are analyzed.展开更多
The sand dredging and its impacts on riverbed evolution and tidal dynamic change in the lower reaches and delta of the Dongjiang River are examined in this paper. The large amount of sand, totally 3.32 billion m3 from...The sand dredging and its impacts on riverbed evolution and tidal dynamic change in the lower reaches and delta of the Dongjiang River are examined in this paper. The large amount of sand, totally 3.32 billion m3 from 1980 to 2002, was mined from the riverbeds of the lower reaches and delta of the Dongjiang River. Increasing of the channel capacity, lowering of the average riverbed elevation, deepening of the water depth and decreasing of the longi- tudinal riverbed gradient are the main effects on the riverbed evolution brought by the large amount of sand dredging. Under the strong sand dredging and associated significant riverbed deformation, the notable changes of the tidal dynamic in the lower reaches and delta of the Dongjiang River occurred, including: (1) in the upper reaches of the Dongjiang River delta and lower reaches of the Dongjiang River, tidal level dropped apparently, tidal range widened, flood tidal duration became longer, amplitudes for major tidal components became bigger and tidal dynamics intensified; (2) tidal wave spread faster; and (3) the limits of the tidal level, tidal current and salt water moved upstream.展开更多
The atmospheric precipitation plays an important role in influencing the river chemistry of the Dongjiang River. The atmospheric contribution to river water is estimated by reference to Cl concentration called Cl ref ...The atmospheric precipitation plays an important role in influencing the river chemistry of the Dongjiang River. The atmospheric contribution to river water is estimated by reference to Cl concentration called Cl ref . The Cl ref of 41 97 μmol/L represents the highest chloride concentration of the rainwater inputs to river water, thus sea salts are responsible for total Cl concentration of the Dongjiang River. According to the principal compositions of precipitation and river water, two approaches sea salt correction and precipitation correction were proposed in order to correct the contribution proportions of atmospheric precipitation on the solutes and to calculate chemical weathering rate. The results reflected that the atmospheric contribution ratios fluctuate from ～5% to ～20% of TDS(total dissolved solids) in the Dongjiang River. As compared with the other world watersheds, the lower dissolved ion contents and high runoff may result in the obvious influence of precipitation on river chemistry in the Dongjiang basin. The major elemental chemistry is mainly controlled by silicate weathering, with the anion HCO - 3 and cation Ca 2+ and Na\++ dominating the major compositions in this basin. The estimated chemical weathering rate of 15 78—23 48 t/(km 2·a) is only 40%—60% of a global average in the Dongjiang basin. Certainly, the estimated results are still under correction gradually because the effect of human activities on the precipitation chemistry has never been quantified in detail.展开更多
基金Under the auspices of National Key Research and Development Program of China(No.2016YFC0503706 2016YFC0503403)+1 种基金National Natural Science Foundation of China(No.31400411)Technical Support Program of the Ministry of Science and Technology of China(No.2013BAC03B05)
文摘Water supply services(WSSs) are critical for the regional water balance and water circulation, but relevant studies have not established the relationship between WSSs and human well-being. This research identifies the scope of areas that benefit from WSSs from an ecosystem service flow perspective. Moreover, the path and quantity of the flow of WSSs are simulated to provide a scientific theoretical basis for ecosystem service management and ecological compensation. The Dongjiang Lake Basin is a national priority river basin in China where ecological compensation pilot programmes concerning water resources are top priorities. Dongjiang Lake Basin experienced an increase and then a decrease in the overall supply of water, with an average net water supply of 1096–1500 mm for the years 1995, 2000, 2005 and 2010. The water demand increased each year in service beneficiary areas(SBAs), varying from 387 to 580 mm. Overall, Dongjiang Lake Basin met the net water demands of the actual SBAs in the lower reaches, but a gap in the water supply and demand emerged gradually. This research provides an understanding of the functional mechanisms for the provision, demand and flow of WSSs and provides a scientific theoretical basis for ecosystem service management and ecological compensation.
基金funded by the National Natural Science Foundation of China (No 40471139)National Basic Research Program of China (No 2004CB 720206)the State Key Laboratory of Loess and Quaternary Geology,Institute of Earth Environment, Chinese Academy of Sci-ences Foundation (No SKLLQG0309)
文摘Layer LJ3 of Linjiang stratigraphic section in Dongjiang River valley in the south of the Nanling Mountains is a set of red sandy sediments.Measured by thermoluminescence(TL) dating,it was found to be formed in MIS2-9,500 ± 800 yr to 19,600 ± 1,800 yr B.P.After analy-sis of the grain sizes of the 16 samples(LJ3-100 to LJ3-85) in this layer,it was discovered that(1) The contents of each grain group in dif-ferent samples are similar.(2) The values of Md,Mz,,Sk,and Kg vary from LJ3-100 to LJ3-85 in a narrow range.(3) The segments of each sample in the accumulative curves extend parallel with similar slopes.All the three aspects reveal the Aeolian characteristics of Layer LJ3.Therefore,it is thought that Layer LJ3 consists of red sandy sediments formed in MIS2 in the south of Nanling Mountain,which reflects the arid climate at that time.
文摘On the background of analysis on region water environment safety in the Dongjiang Lake of south-central China, the source of pollution of water environment and its control are studied. The concept of region environment disaster chain is put forward on the basis of combination study on the disaster chain theory and pollution problem in regional water environment. Through identification and analysis of pollution disaster resources in regional water environment of the Dongjiang Lake, the annual emission of the chemical oxygen demand (COD), ammonia nitrogen, total phosphorus (TP) and heavy metal (Cd, As, Pb) are counted. According to evaluation on structure proportion of contaminants in the Dongjiang Lake, agricultural non-point source is the uppermost pollution source, which accounted for 87.74% in total pollution load. Ammonia nitrogen, TP and COD are mainly contaminants accounted for 94.27% in total pollution load. By analyzing danger of contaminants in the lake, basic form of disaster chain of water environment pollution is built elementarily. It shows characteristics of branches and trunk basin disaster chain and embodies multisource disaster implication chain caused by human activities. Then, disaster resources chain-cutting methods for pollution prevention and control of regional water environment of the Dongjiang Lake are analyzed.
文摘The sand dredging and its impacts on riverbed evolution and tidal dynamic change in the lower reaches and delta of the Dongjiang River are examined in this paper. The large amount of sand, totally 3.32 billion m3 from 1980 to 2002, was mined from the riverbeds of the lower reaches and delta of the Dongjiang River. Increasing of the channel capacity, lowering of the average riverbed elevation, deepening of the water depth and decreasing of the longi- tudinal riverbed gradient are the main effects on the riverbed evolution brought by the large amount of sand dredging. Under the strong sand dredging and associated significant riverbed deformation, the notable changes of the tidal dynamic in the lower reaches and delta of the Dongjiang River occurred, including: (1) in the upper reaches of the Dongjiang River delta and lower reaches of the Dongjiang River, tidal level dropped apparently, tidal range widened, flood tidal duration became longer, amplitudes for major tidal components became bigger and tidal dynamics intensified; (2) tidal wave spread faster; and (3) the limits of the tidal level, tidal current and salt water moved upstream.
文摘The atmospheric precipitation plays an important role in influencing the river chemistry of the Dongjiang River. The atmospheric contribution to river water is estimated by reference to Cl concentration called Cl ref . The Cl ref of 41 97 μmol/L represents the highest chloride concentration of the rainwater inputs to river water, thus sea salts are responsible for total Cl concentration of the Dongjiang River. According to the principal compositions of precipitation and river water, two approaches sea salt correction and precipitation correction were proposed in order to correct the contribution proportions of atmospheric precipitation on the solutes and to calculate chemical weathering rate. The results reflected that the atmospheric contribution ratios fluctuate from ～5% to ～20% of TDS(total dissolved solids) in the Dongjiang River. As compared with the other world watersheds, the lower dissolved ion contents and high runoff may result in the obvious influence of precipitation on river chemistry in the Dongjiang basin. The major elemental chemistry is mainly controlled by silicate weathering, with the anion HCO - 3 and cation Ca 2+ and Na\++ dominating the major compositions in this basin. The estimated chemical weathering rate of 15 78—23 48 t/(km 2·a) is only 40%—60% of a global average in the Dongjiang basin. Certainly, the estimated results are still under correction gradually because the effect of human activities on the precipitation chemistry has never been quantified in detail.
基金National Natural Science Foundation of China, No.41101152 No.40901090+5 种基金 No.41172315 The Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry The talents in- troduced into Universities Foundation of Guangdong Province of China The China Scholarship Council （CSC） funding in 2013 The Universities Disciplinary and Special Construction Funds of Guangdong Prov- ince Foundation, No.C 10092 The Scientific Research Foundation of Graduate School of South China Nor- mal University
