Effects of soil moisture on cotton root length density (total root length per unit soil volume) and yield under drip irrigation with plastic mulch were studied through field experiments. The results indicate that spat...Effects of soil moisture on cotton root length density (total root length per unit soil volume) and yield under drip irrigation with plastic mulch were studied through field experiments. The results indicate that spatial distributions of root length density of cotton under various water treatments were basically similar. Horizontally, both root length densities of cotton in wide and narrow rows were similar, and higher than that between mulches. Vertically, root length density of cotton decreased with increasing soil depth. The distribution of root length density is different under different irrigation treatments. In conditions of over-irrigation, the root length density of cotton between mulches would increase. However, it would decrease in both the wide rows and narrow rows. The mean root length density of cotton increased with increasing irrigation water. Water stress caused the root length density to increase in lower soil layers. There is a significant correlation between root length density and yields of cotton at the flower-boll and wadding stages. The regression between irrigation amount and yield of cotton can be expressed as y = -0.0026x2+18.015x-24845 (R2 = 0.959). It showed that the irrigation volume of 3,464.4 m3/hm2 led to op-timal root length density. The yield of cotton was 6,360 .8 kg/hm2 under that amount of irrigation.展开更多
The primary purpose of this research was to give suitable irrigation program according to the growth period and water requirement.A cotton field experiment with mulched drip irrigation was conducted at the National Fi...The primary purpose of this research was to give suitable irrigation program according to the growth period and water requirement.A cotton field experiment with mulched drip irrigation was conducted at the National Field Observation and Research Station for Oasis Farmland Ecosystem in Aksu of Xinjiang in 2008.Water balance method was adopted to study the water requirement and water consumption law of cotton under mulched drip irrigation in Tarim Irrigated Area.Statistical analysis of experimental data of irrigation indicates that the relationship between yield of cotton and irrigation presents a quadratic parabola.We fit the model of cotton water production on the basis of field experimental data of cotton.And the analysis on water saving benefit of cotton under mulched drip irrigation was done.Results indicate that water requirements for the irrigated cotton are 543 mm in Tarim Irrigated Area.The water requirements of seedling stage is 252 mm,budding stage is 186 mm,bolling stage is 316 mm and wadding stage is 139 mm.the irrigation amount determines the spatial distribution of soil moisture and water consumption during cotton life cycle.However,water consumption at different growth stages was inconsistent with irrigation.Quantitatively,the water consumed by cotton decreases upon the increase of irrigation amount.From the perspective of water saving,the maximal water use efficiency can reach 3 091 m3/ha.But the highest cotton yield needs 3464 m3/ha irrigation water.In summary,compared to the conventional drip irrigation,a number of benefits in water saving and yield increase were observed when using plastic mulch.At the same amount of irrigation,the cotton yield with plastic mulch was 30.2% higher than conventional approaches,and the efficiency of water utilization increased by30.2%.While at the same yield level,29.3% water was saved by using plastic mulch,and the efficiency increased by 41.5%.展开更多
High salinity in soil can prevent root growth of most plants. To investigate soil salinity dynamics under drip irrigation with mulch film （DI） and its effects on cotton root length, we conducted field experiments in...High salinity in soil can prevent root growth of most plants. To investigate soil salinity dynamics under drip irrigation with mulch film （DI） and its effects on cotton root length, we conducted field experiments in saline soil based on a monolith method using flooding irrigation with mulch film （FI） as a control at the Korla Experimental Station of the Xinjiang Academy of Agricultural Sciences, China in 2009 and 2010. The results showed that the total root length decreased 120 days after sowing （DAS） under DI, and was mainly centered in the 0-30 cm soil layer and at distances of 30-70 cm from the drip-lines. There was almost complete overlap in the area of root length decline and salt accumulation. In the soil depth of 0-30 cm and at distances of 30-70 cm from the drip-lines at 110 to 160 DAS in 2009 and 171 DAS in 2010, the electrical conductivity （EC） in all soil samples was at least 3 mS/cm and in some cases exceeded 5 mS/cm under DI treatment. However, EC barely exceeded 3 mS/cm and no reduction in root length was observed under FI treatment. Correlation analysis of soil EC and root length density indicated that the root length declined when the soil EC exceeded 2.8 mS/cm. The main reason for the decrease of root length in cotton under DI was localized accumulation of salinity.展开更多
In sub-humid Northeast China,plastic film mulching(PFM)is increasingly used with drip irrigation system in maize(Zea mays L.)to cope with seasonal droughts and low temperatures during seedling stage.Although there wer...In sub-humid Northeast China,plastic film mulching(PFM)is increasingly used with drip irrigation system in maize(Zea mays L.)to cope with seasonal droughts and low temperatures during seedling stage.Although there were several studies showing the benefits of PFM on maize production in the region,quantification of the effects of PFM in sub-humid Northeast China are still lacking.Hybrid-Maize model has a special version that can not only simulate the effects of PFM on reduction of soil evaporation and rise of topsoil temperature,but also simulate the effects of PFM on crop development and other physiological processes.This paper reports how to verify the Hybrid-Maize model against observations and then applying the model to quantify effects of PFM on grain yield and water use efficiency(WUE)under irrigated scenarios.The Hybrid-Maize model was added the heating effects of PFM on rising surface-soil temperature and promoting subsequent crop development by establishing equations between surface-soil temperature and air temperature before V6 stage.A 3-year field experiment including maize growth and yield data measured at a drip-irrigated field in Heilongjiang Province was used to serve the model calibration.The simulated results indicated that the Hybrid-Maize model performed well in simulation of seasonal soil water storage and in-season aboveground dry matter in three years,but overestimated the leaf area index(LAI)for both treatments and underestimated the final aboveground dry matter at maturity for mulched treatments.Although the Hybrid-Maize model overestimated the grain yield and WUE,it did still reflect the effects of PFM on increasing grain yield and WUE during the three growing seasons.The average simulated grain yield and WUE for mulched treatments were 8%and 13%greater compared to non-mulched treatments using 30 years weather data,which were in agreement with observations that average grain yield and WUE was 11%and 14%increased by PFM,respectively.For evapotranspiration(ET),the average simulated ET for mulched treatments was 22 mm less than non-mulched treatments mainly due to less soil evaporation.For simulated irrigation requirements,at most 69 mm of irrigation water could be saved by PFM.In conclusion,PFM with drip irrigation could improve irrigated maize production in sub-humid Northeast China.展开更多
基金supported by the National 973 project (2009CB421302)the National Project (2007BAC03A0604)the key National Natural Science Foundation (40830640)
文摘Effects of soil moisture on cotton root length density (total root length per unit soil volume) and yield under drip irrigation with plastic mulch were studied through field experiments. The results indicate that spatial distributions of root length density of cotton under various water treatments were basically similar. Horizontally, both root length densities of cotton in wide and narrow rows were similar, and higher than that between mulches. Vertically, root length density of cotton decreased with increasing soil depth. The distribution of root length density is different under different irrigation treatments. In conditions of over-irrigation, the root length density of cotton between mulches would increase. However, it would decrease in both the wide rows and narrow rows. The mean root length density of cotton increased with increasing irrigation water. Water stress caused the root length density to increase in lower soil layers. There is a significant correlation between root length density and yields of cotton at the flower-boll and wadding stages. The regression between irrigation amount and yield of cotton can be expressed as y = -0.0026x2+18.015x-24845 (R2 = 0.959). It showed that the irrigation volume of 3,464.4 m3/hm2 led to op-timal root length density. The yield of cotton was 6,360 .8 kg/hm2 under that amount of irrigation.
基金Supported by 973 Project(2009CB421302)Innovation Project of Chinese Academy of Sciences(KZCX2-YW-127)Youth Science Foundation of China(41401025)
文摘The primary purpose of this research was to give suitable irrigation program according to the growth period and water requirement.A cotton field experiment with mulched drip irrigation was conducted at the National Field Observation and Research Station for Oasis Farmland Ecosystem in Aksu of Xinjiang in 2008.Water balance method was adopted to study the water requirement and water consumption law of cotton under mulched drip irrigation in Tarim Irrigated Area.Statistical analysis of experimental data of irrigation indicates that the relationship between yield of cotton and irrigation presents a quadratic parabola.We fit the model of cotton water production on the basis of field experimental data of cotton.And the analysis on water saving benefit of cotton under mulched drip irrigation was done.Results indicate that water requirements for the irrigated cotton are 543 mm in Tarim Irrigated Area.The water requirements of seedling stage is 252 mm,budding stage is 186 mm,bolling stage is 316 mm and wadding stage is 139 mm.the irrigation amount determines the spatial distribution of soil moisture and water consumption during cotton life cycle.However,water consumption at different growth stages was inconsistent with irrigation.Quantitatively,the water consumed by cotton decreases upon the increase of irrigation amount.From the perspective of water saving,the maximal water use efficiency can reach 3 091 m3/ha.But the highest cotton yield needs 3464 m3/ha irrigation water.In summary,compared to the conventional drip irrigation,a number of benefits in water saving and yield increase were observed when using plastic mulch.At the same amount of irrigation,the cotton yield with plastic mulch was 30.2% higher than conventional approaches,and the efficiency of water utilization increased by30.2%.While at the same yield level,29.3% water was saved by using plastic mulch,and the efficiency increased by 41.5%.
基金funded by the National Natural Science Foundation of China (31000252, 31201681)the Science and Technology Supporting Project of the Department of Science and Technology of Xinjiang, China (200840102-08)
文摘High salinity in soil can prevent root growth of most plants. To investigate soil salinity dynamics under drip irrigation with mulch film （DI） and its effects on cotton root length, we conducted field experiments in saline soil based on a monolith method using flooding irrigation with mulch film （FI） as a control at the Korla Experimental Station of the Xinjiang Academy of Agricultural Sciences, China in 2009 and 2010. The results showed that the total root length decreased 120 days after sowing （DAS） under DI, and was mainly centered in the 0-30 cm soil layer and at distances of 30-70 cm from the drip-lines. There was almost complete overlap in the area of root length decline and salt accumulation. In the soil depth of 0-30 cm and at distances of 30-70 cm from the drip-lines at 110 to 160 DAS in 2009 and 171 DAS in 2010, the electrical conductivity （EC） in all soil samples was at least 3 mS/cm and in some cases exceeded 5 mS/cm under DI treatment. However, EC barely exceeded 3 mS/cm and no reduction in root length was observed under FI treatment. Correlation analysis of soil EC and root length density indicated that the root length declined when the soil EC exceeded 2.8 mS/cm. The main reason for the decrease of root length in cotton under DI was localized accumulation of salinity.
基金supported by the National Natural Science Foundation of China(Grant No.51479211)Ministry of Science and Technology of the People’s Republic of China(Grant No.2014BAD12B05)Chinese Scholarship Council(Grant No.201506350059).
文摘In sub-humid Northeast China,plastic film mulching(PFM)is increasingly used with drip irrigation system in maize(Zea mays L.)to cope with seasonal droughts and low temperatures during seedling stage.Although there were several studies showing the benefits of PFM on maize production in the region,quantification of the effects of PFM in sub-humid Northeast China are still lacking.Hybrid-Maize model has a special version that can not only simulate the effects of PFM on reduction of soil evaporation and rise of topsoil temperature,but also simulate the effects of PFM on crop development and other physiological processes.This paper reports how to verify the Hybrid-Maize model against observations and then applying the model to quantify effects of PFM on grain yield and water use efficiency(WUE)under irrigated scenarios.The Hybrid-Maize model was added the heating effects of PFM on rising surface-soil temperature and promoting subsequent crop development by establishing equations between surface-soil temperature and air temperature before V6 stage.A 3-year field experiment including maize growth and yield data measured at a drip-irrigated field in Heilongjiang Province was used to serve the model calibration.The simulated results indicated that the Hybrid-Maize model performed well in simulation of seasonal soil water storage and in-season aboveground dry matter in three years,but overestimated the leaf area index(LAI)for both treatments and underestimated the final aboveground dry matter at maturity for mulched treatments.Although the Hybrid-Maize model overestimated the grain yield and WUE,it did still reflect the effects of PFM on increasing grain yield and WUE during the three growing seasons.The average simulated grain yield and WUE for mulched treatments were 8%and 13%greater compared to non-mulched treatments using 30 years weather data,which were in agreement with observations that average grain yield and WUE was 11%and 14%increased by PFM,respectively.For evapotranspiration(ET),the average simulated ET for mulched treatments was 22 mm less than non-mulched treatments mainly due to less soil evaporation.For simulated irrigation requirements,at most 69 mm of irrigation water could be saved by PFM.In conclusion,PFM with drip irrigation could improve irrigated maize production in sub-humid Northeast China.
