The measurement and observation for this study were carried out by using a three-dimensional (u, v, w) Sonic anemometer (IAP-SA 485), at Forest Ecosystem Opened Research Station of Changbai Mountains (12828扙 and 4224...The measurement and observation for this study were carried out by using a three-dimensional (u, v, w) Sonic anemometer (IAP-SA 485), at Forest Ecosystem Opened Research Station of Changbai Mountains (12828扙 and 4224?N, Jilin Province, P. R. China) in August 2001. The basic characteristics of turbulence, such as turbulence intensity, atmospheric stability, time scales, and convection state, near the forest floor were analyzed. It is concluded that the airflow near forest floor is characterized by high intermittence and asymmetry, and the active and upward movement takes the leading position. Near forest floor, the vertical turbulence is retained and its time scale and length scale are much less than that of u, v components. The eddy near forest floor shows a flat structure and look like a ’Disk’. Buoyancy plays a leading role in the generation and maintenance of local turbulence展开更多
Water uses in small and middle-sized rivers, and non-ecological treatment model has deteriorated local environment in Shandong. The research reviewed ecological environment status quo of small and middle rivers and co...Water uses in small and middle-sized rivers, and non-ecological treatment model has deteriorated local environment in Shandong. The research reviewed ecological environment status quo of small and middle rivers and concluded existing problems. Finally, ecological treatments were proposed based on treatments at home and abroad in order to improve eco-environment of rivers and build better Shandong.展开更多
Xiangxi Tujia and Miao Autonomous Prefecture is located in western Hunan province with abundant pastures,suitable for husbandry.However,parasitic diseases become an obstacle for goat industry development.In the resear...Xiangxi Tujia and Miao Autonomous Prefecture is located in western Hunan province with abundant pastures,suitable for husbandry.However,parasitic diseases become an obstacle for goat industry development.In the research,based on parasite damages,epidemic variety and characters,some prevention measures were proposed,as follows：improving goat raising and management,rotation grazing,reinforcement of disinfection and quarantine,and regular parasite expelling,providing references for goat farming in Xiangxi.展开更多
A study was conducted in a hilly area of Sichuan Province,Southwestern China, to compare the streamflow and soil moisture in two upland watersheds with different land use patterns. One was an agroforestry watershed, w...A study was conducted in a hilly area of Sichuan Province,Southwestern China, to compare the streamflow and soil moisture in two upland watersheds with different land use patterns. One was an agroforestry watershed, which consisted mainly of trees with alder (Alnus cremastogyne Burkill) and cypress (Cupressus funebris Endl.) planted in belts or strips with a coverage of about 46%, and the other was a grassland primarily composed of lalang grass (Imperata cylindrica var. major (Nees) C. E. Hubb.), filamentary clematis (Clematis filamentosa Dunn) and common eulaliopsis (Eulaliopsis binata (Retz.) C. E. Hubb) with a coverage of about 44%. Streamflow measurement with a hydrograph established at the watershed outlet showed that the average annual streamflow per 100 mm rainfall from 1983 to 1992 was 0.36 and 1.08 L s-1 km-2 for the agroforestry watershed and the grass watershed, respectively. This showed that the streamflow of the agroforestry watershed was reduced by 67% when compared to that of the grass watershed. The peak average monthly streamflow in the agroforestry watershed was over 5 times lower than that of the grass watershed and lagged by one month. In addition, the peak streamflow during a typical rainfall event of 38.3 mm in August 1986 was 37% lower in the agroforestry watershed than in the grass watershed. Results of the moisture contents of the soil samples from 3 slope locations (upper, middle and lower slopes) indicated that the agroforestry watershed maintained generally higher soil moisture contents than the grass watershed within 0-20 and 20-80 cm soil depths for the upper slope, especially for the period from May through July. For the other (middle and lower) slopes, soil moisture contents within 20-80 cm depth in the agroforestry watershed was generally lower than those in the grass watershed, particularly in September, revealing that water consumption by trees took place mainly below the plow layer. Therefore, agroforestry land use types might offer a complimentary model for tree-annual crop water utilization.展开更多
Under the guide of system theory, taking the oasis in the Sangong River watershed as a case study, this paper analyzes the oasis structure and function from 4 aspects including oasis spatial structure, water resources...Under the guide of system theory, taking the oasis in the Sangong River watershed as a case study, this paper analyzes the oasis structure and function from 4 aspects including oasis spatial structure, water resources structure, vegetation structure, economic structure and their corresponding functions. The results indicate that as a typical small-scale watershed, Sangong River watershed has the relatively complete mountain-basin structure, and ecological and productive function. Because of human drastic activity the utilization rate of water resources was as high as 98.7%, and the utilization of groundwater was not reasonable, which resulted in an average annual decline of 0.353m in the water table of alluvial-diluvial-fan oasis, and an average annual increase of 0.047m in the alluvial-plain. The layout of crop and shelter forest benefits to the utilization of water and land resources. The development of oasis economy is at low level, and its eco-economic function is weak.展开更多
The study investigated the streamflow response to the shrinking cryosphere under changing climate in the Lidder valley, Upper Indus Basin(UIB), Kashmir Himalayas. We used a combination of multitemporal satellite data ...The study investigated the streamflow response to the shrinking cryosphere under changing climate in the Lidder valley, Upper Indus Basin(UIB), Kashmir Himalayas. We used a combination of multitemporal satellite data and topographic maps to evaluate the changes in area, length and volume of the glaciers from 1962 to 2013. A total of 37 glaciers from the Lidder valley, with an area of 39.76 km^2 in 1962 were selected for research in this study. It was observed that the glaciers in the valley have lost ~28.89 ±0.1% of the area and ~19.65 ±0.069% of the volume during the last 51 years, with variable interdecadal recession rates. Geomorphic and climatic influences on the shrinking glacier resources were studied. 30-years temperature records(1980-2010) in the study area showed a significant increasing trend in all the seasons. However, the total annual precipitation during the same period showed a nonsignificant decreasing trend except during the late summer months(July, August and September), when the increasing trend is significant. The depletion of glaciers has led to the significant depletion of the streamflows under the changing climate in the valley. Summer streamflows(1971-2012) have increased significantly till mid-nineties but decreased significantly thereafter, suggesting that the tipping point of streamflow peak, due to the enhanced glacier-melt contribution under increasing global temperatures, may have been already reached in the basin. The observed glacier recession and climate change patterns, if continued in future, would further deplete the streamflows with serious implications on water supplies for different uses in the region.展开更多
As a component of streamflow, baseflow is critical for regulating seasonal distribution of river fows and stabilizing water supplies. Water resources in the arid area of Northwest China are mainly from multiple catchm...As a component of streamflow, baseflow is critical for regulating seasonal distribution of river fows and stabilizing water supplies. Water resources in the arid area of Northwest China are mainly from multiple catchments in the alpine that could be influenced by varieties of climatic, land cover, soil and geological factors. While numerous studies have been done on streamflow, systematic analysis of baseflow in the alpine river systems is scare. Based on historical daily streamflow data and the automated digital filter method of baseflow separation, this study investigated characteristics of hydrographs of overland flow, streamflow and baseflowof river systems fed by rainfall, snowmelt, glacier melt or mixtures of these. This study also calculated the recession constants and baseflow indices of 65 river systems. While the recession constant was o.oo34- o.o728 with a mean of o.o18, the baseflow index was 0.27-0.79 with a mean of 0.57. Further, Spearman＇s correlation analysis showed that the baseflow index was significantly correlated with catchment climatic factors （e.g., precipitation and temperature）, topographic factors （e.g., elevation and slope） and aquifer properties represented by the recession constant. Multiple regression analysis indicated that the factors explained 65% of the variability of baseflow index in the studv area.展开更多
Tree-ring chronologies from pine,oak and black locust tree species were used to reconstruct annual streamflow and examine hydrological drought years for Palgong Mountain forested watershed in southeastern South Korea ...Tree-ring chronologies from pine,oak and black locust tree species were used to reconstruct annual streamflow and examine hydrological drought years for Palgong Mountain forested watershed in southeastern South Korea for the period from 1954-2015. The backward elimination multiple regression analysis provided the statistically significant predictor chronologies of streamflow. The final calibration and verification test models accounted for 84.8% and 81.6%,respectively,of the variability in streamflow observed in the gage data. Further verification of the validity of the reconstructed model was undertaken with the Pearson Correlation Coefficient,the Reduction of Error Test,and the Durbin-Watson Statistics and indicated fidelity of the model for reconstructing the annual streamflow. Analyses of the reconstructed annual streamflow indicate that the most persistent years of high flows above the median annual discharge occurred from 1986-2008.This period included 7 single or multiple years of highest flow above the 90 th percentile discharge and multiple years of high flows with a time interval of 2-6 years,although with intervening multiple years of low flows below the 10 th and 50 th percentile. In comparison,the most persistent years of low flows below the median annual discharge occurred from 1954-1985 and 2009-2015. This period included 8 single or multiple years of lowest flow below the 10 th percentiledischarge and multiple years of low flows with a time interval of 2-9 years,although also with intervening multiple years of high flows above the 50 th percentile. No single years of extreme hydrological droughts below the 10 th percentile were identified from 1986-2015 whereas a greater proportion of high flows above the 90 th percentile occurred during this period. The persistent single or multiple years of lowest flows between 1954 and 1985 were the recent most critical hydrological drought years identified in the Palgong Mountain forested watershed providing supportive evidence of the severity of past hydrological droughts during that period,applicable to the southeastern South Korea where the study watershed is located. This interpretation agrees with the hydrological drought event years identified from 1951 to the early 1980 s in a related national study that used precipitation proxy data to reconstruct past occurrences of droughts in Korea.展开更多
基金This study was supported by the grand of the Knowledge Innovation Program of the Chinese Academy of Sciences (KZCX1-SW-01) and National Natural Science Foundation (30070158).
文摘The measurement and observation for this study were carried out by using a three-dimensional (u, v, w) Sonic anemometer (IAP-SA 485), at Forest Ecosystem Opened Research Station of Changbai Mountains (12828扙 and 4224?N, Jilin Province, P. R. China) in August 2001. The basic characteristics of turbulence, such as turbulence intensity, atmospheric stability, time scales, and convection state, near the forest floor were analyzed. It is concluded that the airflow near forest floor is characterized by high intermittence and asymmetry, and the active and upward movement takes the leading position. Near forest floor, the vertical turbulence is retained and its time scale and length scale are much less than that of u, v components. The eddy near forest floor shows a flat structure and look like a ’Disk’. Buoyancy plays a leading role in the generation and maintenance of local turbulence
基金Supported by Shandong Province Soft Science Research Program(2015RKB01158)the Natural Science Foundation of Shandong Province(ZR2014DL002)Research Initiation Funds for the Introduced Talents in Taishan University(Y-01-2014019)~~
文摘Water uses in small and middle-sized rivers, and non-ecological treatment model has deteriorated local environment in Shandong. The research reviewed ecological environment status quo of small and middle rivers and concluded existing problems. Finally, ecological treatments were proposed based on treatments at home and abroad in order to improve eco-environment of rivers and build better Shandong.
文摘Xiangxi Tujia and Miao Autonomous Prefecture is located in western Hunan province with abundant pastures,suitable for husbandry.However,parasitic diseases become an obstacle for goat industry development.In the research,based on parasite damages,epidemic variety and characters,some prevention measures were proposed,as follows：improving goat raising and management,rotation grazing,reinforcement of disinfection and quarantine,and regular parasite expelling,providing references for goat farming in Xiangxi.
基金Project supported by the Innovation Project of the Chinese Academy of Sciences (Nos. KZCX3-SW-330 and KZCX2-413) and the National Natural Science Youth Foundation of China (No. 40201029).
文摘A study was conducted in a hilly area of Sichuan Province,Southwestern China, to compare the streamflow and soil moisture in two upland watersheds with different land use patterns. One was an agroforestry watershed, which consisted mainly of trees with alder (Alnus cremastogyne Burkill) and cypress (Cupressus funebris Endl.) planted in belts or strips with a coverage of about 46%, and the other was a grassland primarily composed of lalang grass (Imperata cylindrica var. major (Nees) C. E. Hubb.), filamentary clematis (Clematis filamentosa Dunn) and common eulaliopsis (Eulaliopsis binata (Retz.) C. E. Hubb) with a coverage of about 44%. Streamflow measurement with a hydrograph established at the watershed outlet showed that the average annual streamflow per 100 mm rainfall from 1983 to 1992 was 0.36 and 1.08 L s-1 km-2 for the agroforestry watershed and the grass watershed, respectively. This showed that the streamflow of the agroforestry watershed was reduced by 67% when compared to that of the grass watershed. The peak average monthly streamflow in the agroforestry watershed was over 5 times lower than that of the grass watershed and lagged by one month. In addition, the peak streamflow during a typical rainfall event of 38.3 mm in August 1986 was 37% lower in the agroforestry watershed than in the grass watershed. Results of the moisture contents of the soil samples from 3 slope locations (upper, middle and lower slopes) indicated that the agroforestry watershed maintained generally higher soil moisture contents than the grass watershed within 0-20 and 20-80 cm soil depths for the upper slope, especially for the period from May through July. For the other (middle and lower) slopes, soil moisture contents within 20-80 cm depth in the agroforestry watershed was generally lower than those in the grass watershed, particularly in September, revealing that water consumption by trees took place mainly below the plow layer. Therefore, agroforestry land use types might offer a complimentary model for tree-annual crop water utilization.
基金Under the auspices of Project of Western Light Related to Eastern Scholar, the National Natural Science Foundation of China (No. 40471134)
文摘Under the guide of system theory, taking the oasis in the Sangong River watershed as a case study, this paper analyzes the oasis structure and function from 4 aspects including oasis spatial structure, water resources structure, vegetation structure, economic structure and their corresponding functions. The results indicate that as a typical small-scale watershed, Sangong River watershed has the relatively complete mountain-basin structure, and ecological and productive function. Because of human drastic activity the utilization rate of water resources was as high as 98.7%, and the utilization of groundwater was not reasonable, which resulted in an average annual decline of 0.353m in the water table of alluvial-diluvial-fan oasis, and an average annual increase of 0.047m in the alluvial-plain. The layout of crop and shelter forest benefits to the utilization of water and land resources. The development of oasis economy is at low level, and its eco-economic function is weak.
基金part of the Department of Science and Technology(DST),Government of India sponsored national research project titled“Himalayan Cryosphere:Science and Society”
文摘The study investigated the streamflow response to the shrinking cryosphere under changing climate in the Lidder valley, Upper Indus Basin(UIB), Kashmir Himalayas. We used a combination of multitemporal satellite data and topographic maps to evaluate the changes in area, length and volume of the glaciers from 1962 to 2013. A total of 37 glaciers from the Lidder valley, with an area of 39.76 km^2 in 1962 were selected for research in this study. It was observed that the glaciers in the valley have lost ~28.89 ±0.1% of the area and ~19.65 ±0.069% of the volume during the last 51 years, with variable interdecadal recession rates. Geomorphic and climatic influences on the shrinking glacier resources were studied. 30-years temperature records(1980-2010) in the study area showed a significant increasing trend in all the seasons. However, the total annual precipitation during the same period showed a nonsignificant decreasing trend except during the late summer months(July, August and September), when the increasing trend is significant. The depletion of glaciers has led to the significant depletion of the streamflows under the changing climate in the valley. Summer streamflows(1971-2012) have increased significantly till mid-nineties but decreased significantly thereafter, suggesting that the tipping point of streamflow peak, due to the enhanced glacier-melt contribution under increasing global temperatures, may have been already reached in the basin. The observed glacier recession and climate change patterns, if continued in future, would further deplete the streamflows with serious implications on water supplies for different uses in the region.
基金funded by the International Co-operation Program of the Ministry of Science and Technology of China (Grant No. 2010DFA92720)the Project of the National Eleventh-Five Year Research Program of China (Grant No. 2012BAC19B07)
文摘As a component of streamflow, baseflow is critical for regulating seasonal distribution of river fows and stabilizing water supplies. Water resources in the arid area of Northwest China are mainly from multiple catchments in the alpine that could be influenced by varieties of climatic, land cover, soil and geological factors. While numerous studies have been done on streamflow, systematic analysis of baseflow in the alpine river systems is scare. Based on historical daily streamflow data and the automated digital filter method of baseflow separation, this study investigated characteristics of hydrographs of overland flow, streamflow and baseflowof river systems fed by rainfall, snowmelt, glacier melt or mixtures of these. This study also calculated the recession constants and baseflow indices of 65 river systems. While the recession constant was o.oo34- o.o728 with a mean of o.o18, the baseflow index was 0.27-0.79 with a mean of 0.57. Further, Spearman＇s correlation analysis showed that the baseflow index was significantly correlated with catchment climatic factors （e.g., precipitation and temperature）, topographic factors （e.g., elevation and slope） and aquifer properties represented by the recession constant. Multiple regression analysis indicated that the factors explained 65% of the variability of baseflow index in the studv area.
基金support of Forest Science and Technology Projects (Project No.S211215L020210) provided by Korea Forest Service
文摘Tree-ring chronologies from pine,oak and black locust tree species were used to reconstruct annual streamflow and examine hydrological drought years for Palgong Mountain forested watershed in southeastern South Korea for the period from 1954-2015. The backward elimination multiple regression analysis provided the statistically significant predictor chronologies of streamflow. The final calibration and verification test models accounted for 84.8% and 81.6%,respectively,of the variability in streamflow observed in the gage data. Further verification of the validity of the reconstructed model was undertaken with the Pearson Correlation Coefficient,the Reduction of Error Test,and the Durbin-Watson Statistics and indicated fidelity of the model for reconstructing the annual streamflow. Analyses of the reconstructed annual streamflow indicate that the most persistent years of high flows above the median annual discharge occurred from 1986-2008.This period included 7 single or multiple years of highest flow above the 90 th percentile discharge and multiple years of high flows with a time interval of 2-6 years,although with intervening multiple years of low flows below the 10 th and 50 th percentile. In comparison,the most persistent years of low flows below the median annual discharge occurred from 1954-1985 and 2009-2015. This period included 8 single or multiple years of lowest flow below the 10 th percentiledischarge and multiple years of low flows with a time interval of 2-9 years,although also with intervening multiple years of high flows above the 50 th percentile. No single years of extreme hydrological droughts below the 10 th percentile were identified from 1986-2015 whereas a greater proportion of high flows above the 90 th percentile occurred during this period. The persistent single or multiple years of lowest flows between 1954 and 1985 were the recent most critical hydrological drought years identified in the Palgong Mountain forested watershed providing supportive evidence of the severity of past hydrological droughts during that period,applicable to the southeastern South Korea where the study watershed is located. This interpretation agrees with the hydrological drought event years identified from 1951 to the early 1980 s in a related national study that used precipitation proxy data to reconstruct past occurrences of droughts in Korea.
