To investigate the effects of coal mining on soil physical properties,sandy lands with three major vegetation types(Salix psammophila,Populus simonii,and Artemisia ordosica)were investigated by the ring knife method a...To investigate the effects of coal mining on soil physical properties,sandy lands with three major vegetation types(Salix psammophila,Populus simonii,and Artemisia ordosica)were investigated by the ring knife method and double-ring infiltrometer.Specifically,variations in soil bulk density and water infiltration rate and the influences of coal mining and vegetation type on the properties during different subsidence stages were studied at the Shendong Bulianta mine.The results showed that,in the period before mining,soil bulk density occurred in the order A.ordosica>P.simonii>S.psammophila,with a negative correlation between the initial infiltration rate and steady infiltration rate being observed.In the period during mining and 3 months after mining,there were no significant differences in soil bulk density and water infiltration rate among vegetation types.At 1 year after mining,the soil bulk density occurred in the order A.ordosica>S.psammophila>P.simonii,having a negative correlation with the steady infiltration rate.The water infiltration depths of the S.psammophila,P.simonii and A.ordosica were 50,60,and 30 cm,respectively.The infiltration characters were simulated by the Kostiakov equations,and the simulated and experimental results were consistent.Linear regression revealed that vegetation types and soil bulk density had significant effects on soil initial infiltration rate during the four study periods,and the infiltration rate of the period 1 year after mining was mainly influenced by the soil bulk density of the period before mining.The results indicated that vegetation types had significant effects on soil bulk density,and that the tree-shrub-grass mode was better than one single plantation for water conversation and vegetation recovery in sandy land subjected to mining.展开更多
In order to study the effects of organic compound fertilizers on soil water infiltration characteristics,an indoor one-dimensional soil column water infiltration test was carried out.Six soil sample treatment groups w...In order to study the effects of organic compound fertilizers on soil water infiltration characteristics,an indoor one-dimensional soil column water infiltration test was carried out.Six soil sample treatment groups were set,namely marshy solonchak(control check,CK for short),bamboo charcoal-mixed marshy solonchak,Difuyuan-mixed marshy solonchak,salined flavo-aquic soil(CK),bamboo charcoal-mixed salined flavo-aquic soil and Difuyuan-mixed salined flavo-aquic soil.After 120 min of infiltration,compared with the CK groups of marshy solonchak and salined flavo-aquic soil,the cumulative infiltration volumes of the bamboo charcoal and difuyuan treatment groups increased by -18.78%,-3.93% and 25.77%,6.53%,respectively;and the displacement increased by -18.93%,1.64% and 22.6%,12.5%,respectively.The relationship between the wetting front displacement and time conformed to a linear function.The effects of organic compound fertilizers on the initial infiltration rates of marshy solonchak and salined flavo-aquic soil were significant,and the relationship between infiltration rate and time conformed to a power function.The vertical distribution of soil moisture under the application of organic compound fertilizers showed that the moisture content changed relatively small within 5 cm of the surface soil layer,then decreased slowly within 5-10 cm of the soil layer,and decreased drastically below 10 cm of soil layer;and relative to the CK group,the application of organic compound fertilizers was beneficial to increase the moisture content of salined flavo-aquic soil.The organic compound fertilizers reduced the water infiltration capacity of marshy solonchak and improved the water infiltration capacity of salined flavo-aquic soil.Compared with Difuyuan,bamboo charcoal reduced the water infiltration capacity of marshy solonchak better and improved the water permeability of salined flavo-aquic soil more significantly.展开更多
By testing soil organic matter （SOM） contents, soil water contents （SWC） within low suctions, and saturated infiltration rates of samples taken from east slope of Gongga Mountain of China, the enhancive effects of...By testing soil organic matter （SOM） contents, soil water contents （SWC） within low suctions, and saturated infiltration rates of samples taken from east slope of Gongga Mountain of China, the enhancive effects of SOM contents on SWC within low suctions and saturated infiltration rates were quantified. The simulated functions might be applied on regional experience forest-hydrology model. The improving function of protecting forest floor and increasing SOM contents on forest ecosystem hydrological effects were also embodied.展开更多
Soil salinization is an issue of global concern.Despite recent evidence indicates that application of sediments into saline-alkali soil in Yellow River Delta as an additive can increase crop yield,its effects on soil ...Soil salinization is an issue of global concern.Despite recent evidence indicates that application of sediments into saline-alkali soil in Yellow River Delta as an additive can increase crop yield,its effects on soil structure and infiltration remain uncertain.In this study,the comprehensively analyses were conducted on the soil infiltration and microstructure of the soil treated with three sediment application layers(surface layer at 0-15 cm,lower layer at 15-30 cm,and plough layer at 0-30 cm)and four sediment incorporation rates(0,2%,5%and 10%),using soil column simulation experiment.Results indicated that the dredged Yellow River sediments can improve the infiltration capacity of saline-alkali soil;and the infiltration capacity increased with the rising sediment incorporation rate under the given application pattern.Compared with the control,applying dredged Yellow River sediments at 10%rate at lower layer and plough layer significantly facilitated the soil infiltration of the saline-alkali soil.Soil macro-porosity for T2,T5 and T10 was 26%,52%and 158%more than that for the control,respectively.This phenomenon was attributed to the increased soil macro-porosity,due to the improved soil microstructure with the incorporation of sediment into the saline-alkali soil.Moreover,the cumulative infiltration was fitted better with Kostiakov infiltration model than Horton and Philip models.展开更多
Subsurface soil water redistribution on the South African Tukulu, also referred as the Cutanic Luvisols in other countries, was evaluated following single run irrigation （20, 40, 80 and 160 L/min inflow rates） in 90...Subsurface soil water redistribution on the South African Tukulu, also referred as the Cutanic Luvisols in other countries, was evaluated following single run irrigation （20, 40, 80 and 160 L/min inflow rates） in 90 m furrows. Changes in soil water content （SWC） at three horizons were monitored using neutron water meter. Measurements were made every 10 m starting 5 m from the furrow inlet for 455 h. HYDRUS-2D software was used to estimate soil hydraulic parameters through inverse optimization algorithms for redistribution at the inlet, midpoint and furrow end. Optimized model parameters compared with initial estimates recorded satisfactory agreement between measured and predicted soil water content, despite spatial variability. Effective hydraulic conductivity （Keff） for 0-600 mm and 0-850 mm profile flow domains demonstrated linearity with SWC although inconsistencies under field conditions were inevitable. The underlying layer restricted gravity and augmented redistribution with Keff assuming a steeper gradient than normal. Conversion of KCff and soil water content into a ratio assisted in quantifying rate of redistribution at 0-600 mm and 0-850 mm profile depth. Vertical redistribution was found to be limited within the upper 600 mm depth thus providing the opportunity to develop furrow irrigation with confidence that water productivity is optimized.展开更多
基金supported by the National High-Tech Research and Development Projects(863 program)(2013AA102904).
文摘To investigate the effects of coal mining on soil physical properties,sandy lands with three major vegetation types(Salix psammophila,Populus simonii,and Artemisia ordosica)were investigated by the ring knife method and double-ring infiltrometer.Specifically,variations in soil bulk density and water infiltration rate and the influences of coal mining and vegetation type on the properties during different subsidence stages were studied at the Shendong Bulianta mine.The results showed that,in the period before mining,soil bulk density occurred in the order A.ordosica>P.simonii>S.psammophila,with a negative correlation between the initial infiltration rate and steady infiltration rate being observed.In the period during mining and 3 months after mining,there were no significant differences in soil bulk density and water infiltration rate among vegetation types.At 1 year after mining,the soil bulk density occurred in the order A.ordosica>S.psammophila>P.simonii,having a negative correlation with the steady infiltration rate.The water infiltration depths of the S.psammophila,P.simonii and A.ordosica were 50,60,and 30 cm,respectively.The infiltration characters were simulated by the Kostiakov equations,and the simulated and experimental results were consistent.Linear regression revealed that vegetation types and soil bulk density had significant effects on soil initial infiltration rate during the four study periods,and the infiltration rate of the period 1 year after mining was mainly influenced by the soil bulk density of the period before mining.The results indicated that vegetation types had significant effects on soil bulk density,and that the tree-shrub-grass mode was better than one single plantation for water conversation and vegetation recovery in sandy land subjected to mining.
基金Supported by National Key Program of Science and Technology(2006BAC01A16)Natural Science Foundation Project of Chongqing(CSTC,2009BA0002)The special fund project for the scientific reserch of the forest public welfare industry(No.201204212).
文摘In order to study the effects of organic compound fertilizers on soil water infiltration characteristics,an indoor one-dimensional soil column water infiltration test was carried out.Six soil sample treatment groups were set,namely marshy solonchak(control check,CK for short),bamboo charcoal-mixed marshy solonchak,Difuyuan-mixed marshy solonchak,salined flavo-aquic soil(CK),bamboo charcoal-mixed salined flavo-aquic soil and Difuyuan-mixed salined flavo-aquic soil.After 120 min of infiltration,compared with the CK groups of marshy solonchak and salined flavo-aquic soil,the cumulative infiltration volumes of the bamboo charcoal and difuyuan treatment groups increased by -18.78%,-3.93% and 25.77%,6.53%,respectively;and the displacement increased by -18.93%,1.64% and 22.6%,12.5%,respectively.The relationship between the wetting front displacement and time conformed to a linear function.The effects of organic compound fertilizers on the initial infiltration rates of marshy solonchak and salined flavo-aquic soil were significant,and the relationship between infiltration rate and time conformed to a power function.The vertical distribution of soil moisture under the application of organic compound fertilizers showed that the moisture content changed relatively small within 5 cm of the surface soil layer,then decreased slowly within 5-10 cm of the soil layer,and decreased drastically below 10 cm of soil layer;and relative to the CK group,the application of organic compound fertilizers was beneficial to increase the moisture content of salined flavo-aquic soil.The organic compound fertilizers reduced the water infiltration capacity of marshy solonchak and improved the water infiltration capacity of salined flavo-aquic soil.Compared with Difuyuan,bamboo charcoal reduced the water infiltration capacity of marshy solonchak better and improved the water permeability of salined flavo-aquic soil more significantly.
基金This research was supported by the Knowledge Innovation Project of Chinese Academy of Sciences (KZCX2-SW-319).
文摘By testing soil organic matter （SOM） contents, soil water contents （SWC） within low suctions, and saturated infiltration rates of samples taken from east slope of Gongga Mountain of China, the enhancive effects of SOM contents on SWC within low suctions and saturated infiltration rates were quantified. The simulated functions might be applied on regional experience forest-hydrology model. The improving function of protecting forest floor and increasing SOM contents on forest ecosystem hydrological effects were also embodied.
基金This work was supported by the National Natural Science Foundation of China(Grant No.51574156)the Key Development Program for Research of Shandong Province(Grant No.2018GNC110023)The authors would like to thank the anonymous reviews and editors for their constructive suggestions which greatly improve the quality of this manuscript.
文摘Soil salinization is an issue of global concern.Despite recent evidence indicates that application of sediments into saline-alkali soil in Yellow River Delta as an additive can increase crop yield,its effects on soil structure and infiltration remain uncertain.In this study,the comprehensively analyses were conducted on the soil infiltration and microstructure of the soil treated with three sediment application layers(surface layer at 0-15 cm,lower layer at 15-30 cm,and plough layer at 0-30 cm)and four sediment incorporation rates(0,2%,5%and 10%),using soil column simulation experiment.Results indicated that the dredged Yellow River sediments can improve the infiltration capacity of saline-alkali soil;and the infiltration capacity increased with the rising sediment incorporation rate under the given application pattern.Compared with the control,applying dredged Yellow River sediments at 10%rate at lower layer and plough layer significantly facilitated the soil infiltration of the saline-alkali soil.Soil macro-porosity for T2,T5 and T10 was 26%,52%and 158%more than that for the control,respectively.This phenomenon was attributed to the increased soil macro-porosity,due to the improved soil microstructure with the incorporation of sediment into the saline-alkali soil.Moreover,the cumulative infiltration was fitted better with Kostiakov infiltration model than Horton and Philip models.
文摘Subsurface soil water redistribution on the South African Tukulu, also referred as the Cutanic Luvisols in other countries, was evaluated following single run irrigation （20, 40, 80 and 160 L/min inflow rates） in 90 m furrows. Changes in soil water content （SWC） at three horizons were monitored using neutron water meter. Measurements were made every 10 m starting 5 m from the furrow inlet for 455 h. HYDRUS-2D software was used to estimate soil hydraulic parameters through inverse optimization algorithms for redistribution at the inlet, midpoint and furrow end. Optimized model parameters compared with initial estimates recorded satisfactory agreement between measured and predicted soil water content, despite spatial variability. Effective hydraulic conductivity （Keff） for 0-600 mm and 0-850 mm profile flow domains demonstrated linearity with SWC although inconsistencies under field conditions were inevitable. The underlying layer restricted gravity and augmented redistribution with Keff assuming a steeper gradient than normal. Conversion of KCff and soil water content into a ratio assisted in quantifying rate of redistribution at 0-600 mm and 0-850 mm profile depth. Vertical redistribution was found to be limited within the upper 600 mm depth thus providing the opportunity to develop furrow irrigation with confidence that water productivity is optimized.
