In order to study the effects of nitrogen fertilizer application methods and nitrogen fertilizer regulation with straw-return on wheat yield and potassium forms in the soil, field experiment was arranged in Pinyuan Co...In order to study the effects of nitrogen fertilizer application methods and nitrogen fertilizer regulation with straw-return on wheat yield and potassium forms in the soil, field experiment was arranged in Pinyuan County, and the effects of the regulation of different ratios of basal to topdressed nitrogen on the yield of wheat and the contents of different forms of potassium in the soil were studied. The re- sults indicated that in the condition of straw-return, the yield of wheat was the high- est after the treatments of the ratios of basal to topdressed nitrogen of 7：3 and 6：4. As to the contents of different forms of potassium, the contents of water-soluble potassium, exchangeable potassium and total potassium treated by the ratios of basal to topdressed nitrogen of 7：3 and 6：4 were the highest, and the differences of non-exchangeable potassium among all treatments were not significant. Under the experiment condition, the ratios of basal to topdressed nitrogen of 7：3 and 6：4 were the best treatments, they can increase the wheat yield and the contents of available potassium and total potassium in the soil.展开更多
●In low-salinity soil,straw-returning did not change necromass contribution to SOC.●In medium-salinity soil,straw-returning reduced necromass contribution to SOC.●Straw-returning reduced POC contribution to SOC in ...●In low-salinity soil,straw-returning did not change necromass contribution to SOC.●In medium-salinity soil,straw-returning reduced necromass contribution to SOC.●Straw-returning reduced POC contribution to SOC in low-salinity soil.●Straw-returning increased POC contribution to SOC in medium-salinity soil.●Salinity affects the contribution of microbial-derived and plant-derived C to SOC.Salinization affects microbial-mediated soil organic carbon(SOC)dynamics.However,the mechanisms of SOC accumulation under agricultural management practices in salt-affected soils remain unclear.We investigated the relative contribution of microbial-derived and plant-derived C to SOC accumulation in coastal salt-affected soils under straw-returning,by determining microbial necromass biomarkers(amino sugars)and particulate organic C(POC).Results showed that,straw-returning increased necromass accumulation in low-salinity soil but did not change its contribution to SOC.In medium-salinity soil,straw-returning did not increase necromass accumulation but decreased its contribution to SOC.In low-and medium-salinity soils,the contribution of POC to SOC showed the opposite direction to that of the necromass.These results suggest that under straw-returning,the relative contribution of microbial-derived C to SOC decreased with increasing salinity,whereas the reverse was true for plant-derived C.Our results highlighted that straw-returning reduces the contribution of microbial anabolism to SOC accumulation in salt-affected soils with increasing salinity.展开更多
Due to the arid climate,flat terrain,certain irrigation sources and high popularization of mechanical harvest in Hexi Irrigation Area of Gansu Province,the widely adopted half film-flat-mulching for corn cultivation f...Due to the arid climate,flat terrain,certain irrigation sources and high popularization of mechanical harvest in Hexi Irrigation Area of Gansu Province,the widely adopted half film-flat-mulching for corn cultivation faces serious adverse situations,such as high soil compactness,strong film-soil adhesion,significant straw stubble and thick covering accumulation on film.Therefore,a new kind of segmented combination upper-side-discharge straw-returning and bundle self-unloading integrated corn residual film recycling machine was proposed.The scheme was characterized by small volume,low resistance,low complexity and film-impurities twice separation.It is constructed based on the concept of module subsection combination.It was composed of film surface straw cleaning device and the followed residual film recycling machine,in terms of function,any usage requirements of separate and joint operations can be satisfied.The film surface straw cleaning device is responsible for the removal of vertical corn straw and ground covering beyond the film.Although its stubble cutter roller obtuse-angle Lshaped blades paired single-helix arrangement is simple,it runs smoothly and the straw crushing effect is good enough.The layout that upper-side-discharge straw-returning cross-range screw conveyor auger is back and beyond the stubble cutter roller,eliminates the common connecting transportation mechanism between crushing and straw-returning section,so that,the system structure can be optimized and the efficiency has been significantly improved.The integrated residual film recycling machine is composed of triangular pyramid arc two-stage wing(TPATSW)type film lifting shovel,rod-tooth-belt type film-impurities separation device and semi-enclosed shaftless bundle film collector.Among them,TPATSW type film lifting shovel has good corn root whisker cutting effect,low soil contact resistance and small soil congestion area,but its ability to lift film is strong,more importantly,the special segmented configuration of shovel handle and the body,shortens the overall machine length significantly.For semi-enclosed shaftless bundle film collector,however,a new scheme of eight sub-rolls rotate in the same direction,to roll the residual film into a bundle is innovatively adopted.Under its own parameters,the system has the lowest sub-roll rotation speed that can bundle the residual film without shaft inside the film collecting chamber,rather than on any subroll itself.The gap between the sub-rolls can separate impurities for the second time.After the film collection reaches the standard,the film collector can dump the residual film directly,which is simple and efficient.The field orthogonal test data of the prototype show that,the optimal parameter combination is:film lifting shovel earth angle is 30°,its operation depth is 50 mm and the machine forward speed is 5.0 km/h.The average residual film recycling rate and the crushed straw qualified rate under the optimal parameters are 84.9%and 90.3%respectively,which meet the requirements of the national and industrial standards.The research solved the passive situation that there was no matching equipment for the recycle of residual film in corn field in Hexi Irrigation Area effectively.展开更多
基金Supported by the Project of National Science and Technology Support Plan-"Integration and Demonstration ration of Straw Resources Recycling Technologies in Huang-HuaiHai Plain Area"(2012BAD14B07)the Project of Major Application Technology Innovation of Agriculture in Shandong Province-"Study on Recycling Technology of Waste Resourcization in Large-scale Farm"+1 种基金the Foundation for Outstanding Young Scientist in Shandong Province-"Study on the Mechanism of the Effect of Drip Irrigation with Saline Water on Soil Environment and Its Crop Response"(BS2011NY017)the Project of National Natural Science Foundation-"Study on the Allocation Pattern and Interface Control of Salinity under the Condition of Brackish Water Irrigation"(51209130)~~
文摘In order to study the effects of nitrogen fertilizer application methods and nitrogen fertilizer regulation with straw-return on wheat yield and potassium forms in the soil, field experiment was arranged in Pinyuan County, and the effects of the regulation of different ratios of basal to topdressed nitrogen on the yield of wheat and the contents of different forms of potassium in the soil were studied. The re- sults indicated that in the condition of straw-return, the yield of wheat was the high- est after the treatments of the ratios of basal to topdressed nitrogen of 7：3 and 6：4. As to the contents of different forms of potassium, the contents of water-soluble potassium, exchangeable potassium and total potassium treated by the ratios of basal to topdressed nitrogen of 7：3 and 6：4 were the highest, and the differences of non-exchangeable potassium among all treatments were not significant. Under the experiment condition, the ratios of basal to topdressed nitrogen of 7：3 and 6：4 were the best treatments, they can increase the wheat yield and the contents of available potassium and total potassium in the soil.
基金supported by the National Key Research and Development Program(2021YFD190090101),Natural Science Foundation of Shandong Province(ZR2022MD093),and China Postdoctoral Science Foundation(2018M632702).
文摘●In low-salinity soil,straw-returning did not change necromass contribution to SOC.●In medium-salinity soil,straw-returning reduced necromass contribution to SOC.●Straw-returning reduced POC contribution to SOC in low-salinity soil.●Straw-returning increased POC contribution to SOC in medium-salinity soil.●Salinity affects the contribution of microbial-derived and plant-derived C to SOC.Salinization affects microbial-mediated soil organic carbon(SOC)dynamics.However,the mechanisms of SOC accumulation under agricultural management practices in salt-affected soils remain unclear.We investigated the relative contribution of microbial-derived and plant-derived C to SOC accumulation in coastal salt-affected soils under straw-returning,by determining microbial necromass biomarkers(amino sugars)and particulate organic C(POC).Results showed that,straw-returning increased necromass accumulation in low-salinity soil but did not change its contribution to SOC.In medium-salinity soil,straw-returning did not increase necromass accumulation but decreased its contribution to SOC.In low-and medium-salinity soils,the contribution of POC to SOC showed the opposite direction to that of the necromass.These results suggest that under straw-returning,the relative contribution of microbial-derived C to SOC decreased with increasing salinity,whereas the reverse was true for plant-derived C.Our results highlighted that straw-returning reduces the contribution of microbial anabolism to SOC accumulation in salt-affected soils with increasing salinity.
基金the support of the Gansu Educational Science and Technology Innovation Project(Grant No.2021CYZC-25)the Gansu Science and Technology Planning Project(Grant No.21CX6NA081)+1 种基金the National Natural Science Foundation of China(Grant No.52165028)the Key Scientific and Technological Program of Gansu Province(Grant No.22ZD6NA046).
文摘Due to the arid climate,flat terrain,certain irrigation sources and high popularization of mechanical harvest in Hexi Irrigation Area of Gansu Province,the widely adopted half film-flat-mulching for corn cultivation faces serious adverse situations,such as high soil compactness,strong film-soil adhesion,significant straw stubble and thick covering accumulation on film.Therefore,a new kind of segmented combination upper-side-discharge straw-returning and bundle self-unloading integrated corn residual film recycling machine was proposed.The scheme was characterized by small volume,low resistance,low complexity and film-impurities twice separation.It is constructed based on the concept of module subsection combination.It was composed of film surface straw cleaning device and the followed residual film recycling machine,in terms of function,any usage requirements of separate and joint operations can be satisfied.The film surface straw cleaning device is responsible for the removal of vertical corn straw and ground covering beyond the film.Although its stubble cutter roller obtuse-angle Lshaped blades paired single-helix arrangement is simple,it runs smoothly and the straw crushing effect is good enough.The layout that upper-side-discharge straw-returning cross-range screw conveyor auger is back and beyond the stubble cutter roller,eliminates the common connecting transportation mechanism between crushing and straw-returning section,so that,the system structure can be optimized and the efficiency has been significantly improved.The integrated residual film recycling machine is composed of triangular pyramid arc two-stage wing(TPATSW)type film lifting shovel,rod-tooth-belt type film-impurities separation device and semi-enclosed shaftless bundle film collector.Among them,TPATSW type film lifting shovel has good corn root whisker cutting effect,low soil contact resistance and small soil congestion area,but its ability to lift film is strong,more importantly,the special segmented configuration of shovel handle and the body,shortens the overall machine length significantly.For semi-enclosed shaftless bundle film collector,however,a new scheme of eight sub-rolls rotate in the same direction,to roll the residual film into a bundle is innovatively adopted.Under its own parameters,the system has the lowest sub-roll rotation speed that can bundle the residual film without shaft inside the film collecting chamber,rather than on any subroll itself.The gap between the sub-rolls can separate impurities for the second time.After the film collection reaches the standard,the film collector can dump the residual film directly,which is simple and efficient.The field orthogonal test data of the prototype show that,the optimal parameter combination is:film lifting shovel earth angle is 30°,its operation depth is 50 mm and the machine forward speed is 5.0 km/h.The average residual film recycling rate and the crushed straw qualified rate under the optimal parameters are 84.9%and 90.3%respectively,which meet the requirements of the national and industrial standards.The research solved the passive situation that there was no matching equipment for the recycle of residual film in corn field in Hexi Irrigation Area effectively.
