To combat the problem of residual film pollution and ensure the sustainable development of agriculture in oasis areas,a field experiment was carried out in 2019 at the Wuyi Farm Corps Irrigation Center Test Station in...To combat the problem of residual film pollution and ensure the sustainable development of agriculture in oasis areas,a field experiment was carried out in 2019 at the Wuyi Farm Corps Irrigation Center Test Station in Urumqi,Northwest China.Four types of biodegradable mulches,traditional plastic mulchs and a control group(bare land;referred to as CK)were compared,including a total of six different treatments.Effects of mulching on soil water and heat conditions as well as the yield and quality of processing tomatoes under drip irrigation were examined.In addition,a comparative analysis of economic benefits of biodegradable mulches was performed.Principal component analysis and gray correlation analysis were used to evaluate suitable mulching varieties for planting processing tomatoes under drip irrigation.Our results show that,compared with CK,biodegradable mulches and traditional plastic mulch have a similar effect on retaining soil moisture at the seedling stage but significantly increase soil moisture by 0.5%-1.5%and 1.5%-3.0%in the middle and late growth periods(P<0.050),respectively.The difference in the thermal insulation effect between biodegradable mulch and plastic mulch gradually reduces as the crop grows.Compared with plastic mulch,the average soil temperature at 5-20 cm depth under biodegradable mulches is significantly lowered by 2.04°C-3.52°C and 0.52°C-0.88°C(P<0.050)at the seedling stage and the full growth period,respectively,and the water use efficiency,average fruit yield,and production-investment ratio under biodegradable mulches were reduced by 0.89%-6.63%,3.39%-8.69%,and 0.51%-6.33%(P<0.050),respectively.The comprehensive evaluation analysis suggests that the black oxidized biological double-degradation ecological mulch made from eco-benign plastic is the optimal film type under the study condition.Therefore,from the perspective of sustainable development,biodegradable mulch is a competitive alternative to plastic mulch for large-scale tomato production under drip irrigation in the oasis.展开更多
Warm and ice-rich frozen soil(WIRFS) exhibits lower shear strength due to the weak binding forces between soil particles and ice crystals. To enhance the strength of WIRFS, frozen soil was treated separately with Port...Warm and ice-rich frozen soil(WIRFS) exhibits lower shear strength due to the weak binding forces between soil particles and ice crystals. To enhance the strength of WIRFS, frozen soil was treated separately with Portland, Phosphate, Sulphoaluminate, Portland-Phosphate and PortlandSulphoaluminate cements. After the samples were cured under -1.0°C for 7 days, the microscopic pore distribution characteristics and the macro-mechanical properties of WIRFS were investigated using mercury intrusion porosimetry(MIP), scanning electron microscopy(SEM) and unconfined compressive strength(UCS) tests. To quantitatively analyze the laws of pore-size transformation and the variation of Hausdorff volumetric fractal dimensions for pre-and post-treated WIRFS, the CURVEEXTRACT and Image-Pro Plus(IPP) image analysis system has been developed for analysing SEM images of the soil samples. Statistics of the pore-area dimension and pore-volume dimension were calculated. The results reveal that the cement-based treatment of WIRFS can improve the cementation fill of soil pores and the bond forces between soil particles. There is an evident correlation between the microstructure characteristics and the mechanical properties of the treated WIRFS. As the fractal dimensions of pore-area decrease, the unconfined compressive strength of cement-treated WIRFS increases significantly. In contrast, as the fractal dimensions of pore-volume increases, the unconfined compressive strength decreases remarkably.展开更多
Calculation of the water balance is very important to relieve the pressure on water resources in arid agricultural irrigation areas.This research focused on irrigation water balance calculations in the Manas River Bas...Calculation of the water balance is very important to relieve the pressure on water resources in arid agricultural irrigation areas.This research focused on irrigation water balance calculations in the Manas River Basin of the southern margin of the Junggar Basin of China,and aimed to analyze the groundwater level dynamic trend and response characteristics of the basin water cycle under water-saving irrigation measures.The surface water and groundwater coupling model of MIKE 11-Visual MODFLOW was used to simulate rainfall runoff in mountainous areas,and quantify the contribution of water balance components in the plain irrigation area.Convergence of the delayed watershed in the mountain area was obvious,and when the river runoff exceeded 200 m^(3)/s,the error in the runoff simulation was large.The water balance in the plain agricultural irrigation area was in a negative equilibrium state,and the difference between recharge and discharge was−2.65 billion m^(3).The evapotranspiration was 24.49 billion m^(3) under drip irrigation,accounting for only approximately 51%of the total discharge.The lateral discharge of the unsaturated and saturated aquifers was 15.38 billion m^(3),accounting for approximately 32%of the total discharge.The main reason for the groundwater decline in the irrigation area was closely related to the extraction of groundwater,because the amount of recharge and discharge in the natural state was approximately identical.The MIKE 11-Visual MODFLOW model produced accurate results,and the research method provided a new exploration technique to quantify the effect of water supply mode on the groundwater table.The model is suitable for the management of water resources in arid areas.展开更多
Large-scale water and soil development in inland river basins in arid areas has made changes in landscape composition and structure,threatening the ecological balance.In order to study the trend of land use/cover and ...Large-scale water and soil development in inland river basins in arid areas has made changes in landscape composition and structure,threatening the ecological balance.In order to study the trend of land use/cover and landscape pattern change and its relationship with water resources utilization in Manas River Basin,the land-use data of five periods in 1976,1990,2000,2010 and 2015 were analyzed.The results showed that:(1)During 1976-2015,farmland and construction land continuously increased,forest land and grassland continuously decreased,the water area initially reduced and then increased,the area of saline-alkali land initially increased and then reduced,the overall trend of unused land and the sandy area was decreasing and the area of different time periods is floating.The areas of land-use types either increased or decreased.This indicates that the landscape pattern of the basin changes dramatically,and human activities are the main reasons for this phenomenon;(2)The oasis area increased from 3480.2 km2 in 1976 to 7982.0 km2 in 2015,with an obvious increasing trend.The oasis area clearly increased during 1976-1990,the growth rate was 40.6%,the growth rate of the oasis area was 129.4%.In the last 40 years,the degree of desertification fluctuated and decreased.The increase of the oasis area directly leads to the increase of water resources utilization and aggravates the degree of water resources shortage;(3)The pattern of land-use types showed a non-equilibrium trend.In the region with increasing landscape heterogeneity,the overall landscape pattern was increasingly controlled by the majority of patches.The intensive land management model and drip irrigation under mulch have improved the utilization efficiency of water resources and saved water resources from engineering renovation and irrigation management.展开更多
基金the Scientific and Technological Innovation Team Project in Key Areas(2019CB004)the Water-Saving Irrigation Experiment Project(BTJSSY–201911)of Xinjiang Production and Construction Corps,China。
文摘To combat the problem of residual film pollution and ensure the sustainable development of agriculture in oasis areas,a field experiment was carried out in 2019 at the Wuyi Farm Corps Irrigation Center Test Station in Urumqi,Northwest China.Four types of biodegradable mulches,traditional plastic mulchs and a control group(bare land;referred to as CK)were compared,including a total of six different treatments.Effects of mulching on soil water and heat conditions as well as the yield and quality of processing tomatoes under drip irrigation were examined.In addition,a comparative analysis of economic benefits of biodegradable mulches was performed.Principal component analysis and gray correlation analysis were used to evaluate suitable mulching varieties for planting processing tomatoes under drip irrigation.Our results show that,compared with CK,biodegradable mulches and traditional plastic mulch have a similar effect on retaining soil moisture at the seedling stage but significantly increase soil moisture by 0.5%-1.5%and 1.5%-3.0%in the middle and late growth periods(P<0.050),respectively.The difference in the thermal insulation effect between biodegradable mulch and plastic mulch gradually reduces as the crop grows.Compared with plastic mulch,the average soil temperature at 5-20 cm depth under biodegradable mulches is significantly lowered by 2.04°C-3.52°C and 0.52°C-0.88°C(P<0.050)at the seedling stage and the full growth period,respectively,and the water use efficiency,average fruit yield,and production-investment ratio under biodegradable mulches were reduced by 0.89%-6.63%,3.39%-8.69%,and 0.51%-6.33%(P<0.050),respectively.The comprehensive evaluation analysis suggests that the black oxidized biological double-degradation ecological mulch made from eco-benign plastic is the optimal film type under the study condition.Therefore,from the perspective of sustainable development,biodegradable mulch is a competitive alternative to plastic mulch for large-scale tomato production under drip irrigation in the oasis.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41471062 and 41401087)the State Key Laboratory of Frozen Soil Engineering (Grant No.SKLFSE-ZT-35)
文摘Warm and ice-rich frozen soil(WIRFS) exhibits lower shear strength due to the weak binding forces between soil particles and ice crystals. To enhance the strength of WIRFS, frozen soil was treated separately with Portland, Phosphate, Sulphoaluminate, Portland-Phosphate and PortlandSulphoaluminate cements. After the samples were cured under -1.0°C for 7 days, the microscopic pore distribution characteristics and the macro-mechanical properties of WIRFS were investigated using mercury intrusion porosimetry(MIP), scanning electron microscopy(SEM) and unconfined compressive strength(UCS) tests. To quantitatively analyze the laws of pore-size transformation and the variation of Hausdorff volumetric fractal dimensions for pre-and post-treated WIRFS, the CURVEEXTRACT and Image-Pro Plus(IPP) image analysis system has been developed for analysing SEM images of the soil samples. Statistics of the pore-area dimension and pore-volume dimension were calculated. The results reveal that the cement-based treatment of WIRFS can improve the cementation fill of soil pores and the bond forces between soil particles. There is an evident correlation between the microstructure characteristics and the mechanical properties of the treated WIRFS. As the fractal dimensions of pore-area decrease, the unconfined compressive strength of cement-treated WIRFS increases significantly. In contrast, as the fractal dimensions of pore-volume increases, the unconfined compressive strength decreases remarkably.
基金Project(202206430008) supported by the China Scholarship Council ProgramProject (52104139) supported by the National Natural Science Foundation of China+2 种基金Project(SKLGDUEK2132) supported by the State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining&Technology/China University of Mining&Technology,Beijing,ChinaProjects([2020]2Y030,[2020]2Y019,[2020]3007,[2020]3008,[2022]011) supported by the Science and Technology Planning of Guizhou Province,ChinaProject(2022B01051) supported by the Key Research and Development Special Tasks of Xinjiang Uygur Autonomous Region,China。
基金support from the National Natural Science Fund(41601579,41361096)National Key Development Program(2017YFC0404303,2017YFC0404304,2016YFC0501402)Excellent Youth Teachers Program of Xinjiang Production&Construction Corps(CZ027204).
文摘Calculation of the water balance is very important to relieve the pressure on water resources in arid agricultural irrigation areas.This research focused on irrigation water balance calculations in the Manas River Basin of the southern margin of the Junggar Basin of China,and aimed to analyze the groundwater level dynamic trend and response characteristics of the basin water cycle under water-saving irrigation measures.The surface water and groundwater coupling model of MIKE 11-Visual MODFLOW was used to simulate rainfall runoff in mountainous areas,and quantify the contribution of water balance components in the plain irrigation area.Convergence of the delayed watershed in the mountain area was obvious,and when the river runoff exceeded 200 m^(3)/s,the error in the runoff simulation was large.The water balance in the plain agricultural irrigation area was in a negative equilibrium state,and the difference between recharge and discharge was−2.65 billion m^(3).The evapotranspiration was 24.49 billion m^(3) under drip irrigation,accounting for only approximately 51%of the total discharge.The lateral discharge of the unsaturated and saturated aquifers was 15.38 billion m^(3),accounting for approximately 32%of the total discharge.The main reason for the groundwater decline in the irrigation area was closely related to the extraction of groundwater,because the amount of recharge and discharge in the natural state was approximately identical.The MIKE 11-Visual MODFLOW model produced accurate results,and the research method provided a new exploration technique to quantify the effect of water supply mode on the groundwater table.The model is suitable for the management of water resources in arid areas.
基金This work was financially supported by the National Natural Science Foundation of China(U1803244)Major scientific and technological projects of Xinjiang Production and Construction Corps(2017AA002)+3 种基金Science and Technology Research Project of Xinjiang Production and Construction Corps(2018AB027)Scientific Research Program of Shihezi University(KX00860105,KX008201,CXRC201801)Innovation and Development Support Program of Key Industries in Southern Xinjiang(2020DB001)Key Research and Development Program of National“13th Five-Year Plan”(2016YFC0501402).
文摘Large-scale water and soil development in inland river basins in arid areas has made changes in landscape composition and structure,threatening the ecological balance.In order to study the trend of land use/cover and landscape pattern change and its relationship with water resources utilization in Manas River Basin,the land-use data of five periods in 1976,1990,2000,2010 and 2015 were analyzed.The results showed that:(1)During 1976-2015,farmland and construction land continuously increased,forest land and grassland continuously decreased,the water area initially reduced and then increased,the area of saline-alkali land initially increased and then reduced,the overall trend of unused land and the sandy area was decreasing and the area of different time periods is floating.The areas of land-use types either increased or decreased.This indicates that the landscape pattern of the basin changes dramatically,and human activities are the main reasons for this phenomenon;(2)The oasis area increased from 3480.2 km2 in 1976 to 7982.0 km2 in 2015,with an obvious increasing trend.The oasis area clearly increased during 1976-1990,the growth rate was 40.6%,the growth rate of the oasis area was 129.4%.In the last 40 years,the degree of desertification fluctuated and decreased.The increase of the oasis area directly leads to the increase of water resources utilization and aggravates the degree of water resources shortage;(3)The pattern of land-use types showed a non-equilibrium trend.In the region with increasing landscape heterogeneity,the overall landscape pattern was increasingly controlled by the majority of patches.The intensive land management model and drip irrigation under mulch have improved the utilization efficiency of water resources and saved water resources from engineering renovation and irrigation management.
