Agricultural landscape along the riparian zones is designated as important landscape components for partly controlling water quality, biodiversity, as well as for their aesthetic role in landscapes. Therefore, the cha...Agricultural landscape along the riparian zones is designated as important landscape components for partly controlling water quality, biodiversity, as well as for their aesthetic role in landscapes. Therefore, the change of agricultural landscape along the riparian zones is at the top of the agenda for many policy makers and landscape planners. As a basis for conservation management, sufficient information about landscape structure should be provided. In the present study, we reconstructed the former landscape structure and elucidated the changes in landscape patterns during a period of about 15 years. Two sets of maps were used: a landsat-5 TM image (1987) and landsat-7 ETM image (2002). The frequency index, landscape diversity index and landscape fragmentation index were calculated for analyses. The results showed that: (1) the areas of the irrigated land, river, forest and beach landscape classes presented a decreasing trend while the areas of landscape classes of pool, paddy fields, dry land and construction land increased. (2) Disturbed by human activity, landscape diversity index increased but landscape fragmentation index decreased. In short, Human activities have had important influences on agricultural landscape of the riparian zones along the Yellow River in Henan Province.展开更多
Palaeoflood hydrological study is a frontal subject of global change study. Using sedimentology, geomorphology and OSL dating methods, the typical palaeoflood slackwater deposits were studied in the Qishuihe River val...Palaeoflood hydrological study is a frontal subject of global change study. Using sedimentology, geomorphology and OSL dating methods, the typical palaeoflood slackwater deposits were studied in the Qishuihe River valley. The results showed that five flooding episodes with 21 palaeoflood events occurred during 4300-4250 a B.P., 4250-4190 a B.P., 4190-4100 a B.P., 4100-4000 a B.P. and 3100-3010 a B.P., respectively, during the Holocene period. The palaeoflood peak discharges were calculated with hydrological models. With a combination of the gauged flood, historical flood and palaeoflood hydrological data, the archives of flood events were extended to over 10,000 years in the Qishuihe River valley, and the flood frequency-peak discharge relationship curve was established accurately. These research results played important roles in mitigating flood hazard, hydraulic engineering and also the development of water resources in the semiarid Weihe River basin.展开更多
Promoting ecological protection and high-quality development of the Yellow River Basin is a major national strategy that is planned and promoted by President Xi Jinping.As an important ecological formation in the Yell...Promoting ecological protection and high-quality development of the Yellow River Basin is a major national strategy that is planned and promoted by President Xi Jinping.As an important ecological formation in the Yellow River Basin and an important part of the“China Water Tower,”the Sichuan part of the Yellow River Basin plays an important role in ecological management of the whole basin.Therefore,based on the present situation and the rich experience of ecological protection and high-quality development in the Yellow River Basin in Sichuan,this study puts forward a feasible plan for long-term ecological management of the Yellow River Basin in Sichuan.展开更多
基金Human Geography provincialkeystonesubjectofHenan University
文摘Agricultural landscape along the riparian zones is designated as important landscape components for partly controlling water quality, biodiversity, as well as for their aesthetic role in landscapes. Therefore, the change of agricultural landscape along the riparian zones is at the top of the agenda for many policy makers and landscape planners. As a basis for conservation management, sufficient information about landscape structure should be provided. In the present study, we reconstructed the former landscape structure and elucidated the changes in landscape patterns during a period of about 15 years. Two sets of maps were used: a landsat-5 TM image (1987) and landsat-7 ETM image (2002). The frequency index, landscape diversity index and landscape fragmentation index were calculated for analyses. The results showed that: (1) the areas of the irrigated land, river, forest and beach landscape classes presented a decreasing trend while the areas of landscape classes of pool, paddy fields, dry land and construction land increased. (2) Disturbed by human activity, landscape diversity index increased but landscape fragmentation index decreased. In short, Human activities have had important influences on agricultural landscape of the riparian zones along the Yellow River in Henan Province.
基金National Natural Science Foundation of China, No.40771018Natural Science Foundation of Shaanxi Prov-ince, No.2006D01Basic Research Fund of Shaanxi Normal University, No.200702001
文摘Palaeoflood hydrological study is a frontal subject of global change study. Using sedimentology, geomorphology and OSL dating methods, the typical palaeoflood slackwater deposits were studied in the Qishuihe River valley. The results showed that five flooding episodes with 21 palaeoflood events occurred during 4300-4250 a B.P., 4250-4190 a B.P., 4190-4100 a B.P., 4100-4000 a B.P. and 3100-3010 a B.P., respectively, during the Holocene period. The palaeoflood peak discharges were calculated with hydrological models. With a combination of the gauged flood, historical flood and palaeoflood hydrological data, the archives of flood events were extended to over 10,000 years in the Qishuihe River valley, and the flood frequency-peak discharge relationship curve was established accurately. These research results played important roles in mitigating flood hazard, hydraulic engineering and also the development of water resources in the semiarid Weihe River basin.
文摘Promoting ecological protection and high-quality development of the Yellow River Basin is a major national strategy that is planned and promoted by President Xi Jinping.As an important ecological formation in the Yellow River Basin and an important part of the“China Water Tower,”the Sichuan part of the Yellow River Basin plays an important role in ecological management of the whole basin.Therefore,based on the present situation and the rich experience of ecological protection and high-quality development in the Yellow River Basin in Sichuan,this study puts forward a feasible plan for long-term ecological management of the Yellow River Basin in Sichuan.