It is an important way for salinized soil amelioration to practise comprehensive irriga-tion-drainage scheme with canal,well and drain togather and to utilize surface and groundwaters jointly. In more serious salinize...It is an important way for salinized soil amelioration to practise comprehensive irriga-tion-drainage scheme with canal,well and drain togather and to utilize surface and groundwaters jointly. In more serious salinized region, well-canal mixed irrigation can improvethe irrigated water quality. To fulfil water quality requirements, it is necessary to展开更多
To investigate the effect of irrigation regime,soil clay content and their combination on growth,yield,and water productivity of rice,a shelter experiment was conduct using Randomized Complete Block Design(RCBD)with a...To investigate the effect of irrigation regime,soil clay content and their combination on growth,yield,and water productivity of rice,a shelter experiment was conduct using Randomized Complete Block Design(RCBD)with a factorial arrangement of treatments with four replications.Irrigation regime was the main treatment investigated,set in three levels as R(30 mm-100%)(100%of saturation and 30 mm flooded),R(30 mm-90%)(90%of saturation and 30 mm flooded)and R(30 mm-70%)(70%saturation and 30 mm flooded),respectively.The sub-treatment was soil type,set in three levels as 40%,50%and 60%clay content,respectively.Results showed that irrigation regime and soil clay content had significant effects on growth,yield and water productivity of rice.However,their combination showed no significant impact on panicles number,root biomass,harvest index and irrigation water productivity.Higher soil clay content results in increase in growth,yield,and water productivity of rice.The total water consumption during R(30 mm-100%)was higher than that during R(30 mm-90%)and R(30 mm-70%)because the latter two saturation levels led to the cracking of soil and decrease of total number of irrigations.Cracks were consistently getting more serious with the reduction in soil water content and the increase in soil clay content.Cracks in soil will preferentially become the major routes of water losses,thus water percolation during R(30 mm-70%)was higher than that during R(30 mm-90%)and R(30 mm-100%)after each irrigation event.The total water use under R(30 mm-70%)exceeded the water consumption under R(30 mm-90%)due to the great amount of soil cracking as well as the excessive volume of standing water depth.Considering water consumption and grain yield,the following conclusion can be reached:(i)The reduction in water consumption was greater than the reduction in grain yield in the case of drying soil 10%below saturation before reflooding.(ii)The reduction in water consumption was less than the reduction in grain yield in the case of drying soil 30%below saturation before reflooding;(iii)The increase in water use was greater than the increase in grain yield in the case of maintaining soil moisture at 100%of saturation before reflooding.Therefore,the water use efficiency was recorded in the order of R(30 mm-90%)>R(30 mm-100%)>R(30 mm-70%).展开更多
Water-fertilizer coupling technology has been widely used in the world.Poor soil aeration,low temperature or high temperature can affect the rate of nutrient uptake by crop roots.Aiming at the interaction between wate...Water-fertilizer coupling technology has been widely used in the world.Poor soil aeration,low temperature or high temperature can affect the rate of nutrient uptake by crop roots.Aiming at the interaction between water,fertilizer,dissolved oxygen and temperature(WFOT)coupling model and irrigation flux of tomato in greenhouse,using these four factors with a five-level uniform-precision rotatable central composite design,a mathematical model was established among the four factors affecting tomato yield in a greenhouse,and the optimal combination scheme of WFOT was obtained.Within the test range,tomato yields increased with increasing irrigation quotas(X_(1)),fertilization amount(X_(2)),dissolved oxygen(X_(3))and geothermal pipe water temperature(X_(4)).The magnitude of the effect of each factor of WFOT on tomato yield was in the following order:X_(1),X_(2),X_(4),X_(3)(spring and summer),and X_(1),X_(3),X_(2),X_(4)(autumn and winter).The interaction between high water-low heat and low water-high heat were beneficial for yield increase(spring and summer),the high fertilizer-low heat and low fertilizer-high heat interactions were beneficial to yield increase(autumn and winter).If WFOT agronomic measures were adopted according to the 95%confidence interval,there was a 95%probability that the spring-summer tomato yield will be higher than 89902 kg/hm^(2).The WFOT coupling scheme was X_(1)of 4808-5091 m3/hm^(2),X_(2)(N-P_(2)O_(5)-K_(2)O)of 171-57-84 to 186-62-89 kg/hm^(2),X_(3)of 7.9-8.2 mg/L,and X_(4)of 34.9°C-37.0°C.There was a 95%probability of tomato yield higher than 85209 kg/hm^(2)in autumn and winter,and the WFOT coupling scheme was X_(1)of 5270-5416 m3/hm^(2),X_(2)(N-P_(2)O_(5)-K_(2)O)of 151-50-76 to 167-56-82 kg/hm^(2),X_(3)of 8.0-8.2 mg/L,and X_(4)of 34.1°C-36.2°C.Overall,and the model had a very good simulation effect,with application value.The relative error between spring-summer and autumn-winter yields ranged from 1.12%to 25.34%.The results of the study can provide a theoretical basis for improving the quality and efficiency of greenhouse tomatoes.展开更多
为研究喷头压力对水量分布模型的影响,以低压喷头为例,对其进行水力性能试验.通过计算矩形组合下不同压力的喷灌组合均匀系数Cu和组合分布均匀系数Du,探索喷头压力对水量分布模型的影响.结果表明：对于低压喷头,喷灌强度随压力增大先逐...为研究喷头压力对水量分布模型的影响,以低压喷头为例,对其进行水力性能试验.通过计算矩形组合下不同压力的喷灌组合均匀系数Cu和组合分布均匀系数Du,探索喷头压力对水量分布模型的影响.结果表明：对于低压喷头,喷灌强度随压力增大先逐渐增大,达到一定值后基本保持不变.在距喷头不同距离时,不同压力下的喷灌强度变化情况不同.在低压范围内,压力对喷灌组合均匀系数和组合分布均匀系数的影响较明显.在100~200 k Pa范围下,Cu和Du均随着压力的增大而增大.在200~300 k Pa范围下,Cu与Du均变化不大.最终提出二者的函数关系式,为多因素下水量分布模型的建立提供理论依据.展开更多
文摘It is an important way for salinized soil amelioration to practise comprehensive irriga-tion-drainage scheme with canal,well and drain togather and to utilize surface and groundwaters jointly. In more serious salinized region, well-canal mixed irrigation can improvethe irrigated water quality. To fulfil water quality requirements, it is necessary to
基金This research is supported by the National Natural Science Foundation of China(51079042 and 51309080)Water Conservancy Science and Technology Project of Jiangsu Province.
文摘To investigate the effect of irrigation regime,soil clay content and their combination on growth,yield,and water productivity of rice,a shelter experiment was conduct using Randomized Complete Block Design(RCBD)with a factorial arrangement of treatments with four replications.Irrigation regime was the main treatment investigated,set in three levels as R(30 mm-100%)(100%of saturation and 30 mm flooded),R(30 mm-90%)(90%of saturation and 30 mm flooded)and R(30 mm-70%)(70%saturation and 30 mm flooded),respectively.The sub-treatment was soil type,set in three levels as 40%,50%and 60%clay content,respectively.Results showed that irrigation regime and soil clay content had significant effects on growth,yield and water productivity of rice.However,their combination showed no significant impact on panicles number,root biomass,harvest index and irrigation water productivity.Higher soil clay content results in increase in growth,yield,and water productivity of rice.The total water consumption during R(30 mm-100%)was higher than that during R(30 mm-90%)and R(30 mm-70%)because the latter two saturation levels led to the cracking of soil and decrease of total number of irrigations.Cracks were consistently getting more serious with the reduction in soil water content and the increase in soil clay content.Cracks in soil will preferentially become the major routes of water losses,thus water percolation during R(30 mm-70%)was higher than that during R(30 mm-90%)and R(30 mm-100%)after each irrigation event.The total water use under R(30 mm-70%)exceeded the water consumption under R(30 mm-90%)due to the great amount of soil cracking as well as the excessive volume of standing water depth.Considering water consumption and grain yield,the following conclusion can be reached:(i)The reduction in water consumption was greater than the reduction in grain yield in the case of drying soil 10%below saturation before reflooding.(ii)The reduction in water consumption was less than the reduction in grain yield in the case of drying soil 30%below saturation before reflooding;(iii)The increase in water use was greater than the increase in grain yield in the case of maintaining soil moisture at 100%of saturation before reflooding.Therefore,the water use efficiency was recorded in the order of R(30 mm-90%)>R(30 mm-100%)>R(30 mm-70%).
基金supported by the National Natural Science Foundation of China(Grant No.51869024)the Ningxia Hui Autonomous Region Key Research and Development Plan Major Project(Grant No.2018BBF0202206,2018BBF0202204)+2 种基金the National Natural Science Foundation of China(Grant No.51469027)the first-class discipline of Ningxia High School(Water Engineering Discipline)fiunded project(Grant No.NXYLXK2017A03,NXYLXK2021A03)the Innovation Team of the“Chang Jiang Scholars and Innovation Team Development Program"of the Ministry of Education funded project(Grant No.IRT1067).
文摘Water-fertilizer coupling technology has been widely used in the world.Poor soil aeration,low temperature or high temperature can affect the rate of nutrient uptake by crop roots.Aiming at the interaction between water,fertilizer,dissolved oxygen and temperature(WFOT)coupling model and irrigation flux of tomato in greenhouse,using these four factors with a five-level uniform-precision rotatable central composite design,a mathematical model was established among the four factors affecting tomato yield in a greenhouse,and the optimal combination scheme of WFOT was obtained.Within the test range,tomato yields increased with increasing irrigation quotas(X_(1)),fertilization amount(X_(2)),dissolved oxygen(X_(3))and geothermal pipe water temperature(X_(4)).The magnitude of the effect of each factor of WFOT on tomato yield was in the following order:X_(1),X_(2),X_(4),X_(3)(spring and summer),and X_(1),X_(3),X_(2),X_(4)(autumn and winter).The interaction between high water-low heat and low water-high heat were beneficial for yield increase(spring and summer),the high fertilizer-low heat and low fertilizer-high heat interactions were beneficial to yield increase(autumn and winter).If WFOT agronomic measures were adopted according to the 95%confidence interval,there was a 95%probability that the spring-summer tomato yield will be higher than 89902 kg/hm^(2).The WFOT coupling scheme was X_(1)of 4808-5091 m3/hm^(2),X_(2)(N-P_(2)O_(5)-K_(2)O)of 171-57-84 to 186-62-89 kg/hm^(2),X_(3)of 7.9-8.2 mg/L,and X_(4)of 34.9°C-37.0°C.There was a 95%probability of tomato yield higher than 85209 kg/hm^(2)in autumn and winter,and the WFOT coupling scheme was X_(1)of 5270-5416 m3/hm^(2),X_(2)(N-P_(2)O_(5)-K_(2)O)of 151-50-76 to 167-56-82 kg/hm^(2),X_(3)of 8.0-8.2 mg/L,and X_(4)of 34.1°C-36.2°C.Overall,and the model had a very good simulation effect,with application value.The relative error between spring-summer and autumn-winter yields ranged from 1.12%to 25.34%.The results of the study can provide a theoretical basis for improving the quality and efficiency of greenhouse tomatoes.
文摘为研究喷头压力对水量分布模型的影响,以低压喷头为例,对其进行水力性能试验.通过计算矩形组合下不同压力的喷灌组合均匀系数Cu和组合分布均匀系数Du,探索喷头压力对水量分布模型的影响.结果表明：对于低压喷头,喷灌强度随压力增大先逐渐增大,达到一定值后基本保持不变.在距喷头不同距离时,不同压力下的喷灌强度变化情况不同.在低压范围内,压力对喷灌组合均匀系数和组合分布均匀系数的影响较明显.在100~200 k Pa范围下,Cu和Du均随着压力的增大而增大.在200~300 k Pa范围下,Cu与Du均变化不大.最终提出二者的函数关系式,为多因素下水量分布模型的建立提供理论依据.
