深松和秸秆还田对甘肃引黄灌区土壤物理性状和玉米生产的影响
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摘要
通过在甘肃引黄灌区灰钙土2015—2017年的田间试验,研究深松35 cm秸秆还田、深松35 cm秸秆不还田与传统旋耕秸秆不还田对土壤紧实度、容重、入渗率和0～100 cm土层土壤水分、玉米产量、养分吸收量的影响.结果表明:与深松35 cm秸秆不还田及旋耕秸秆不还田相比,深松35 cm秸秆还田使0～40 cm土层土壤紧实度和容重降低最明显,2017年收获后紧实度与容重较2015年试验前分别下降42.6%、7.0%,且2016和2017年播种前与收获后0～40 cm土层紧实度和容重的变幅最小,紧实度变异系数平均为6.1%,容重为3.2%,土壤入渗率较旋耕秸秆不还田提高33.6%;深松35 cm秸秆还田可显著提高春秋两季0～100 cm土层剖面含水量,降低剖面水分变异,0～100 cm土层土壤贮水量较旋耕秸秆不还田春季增加15.5%,秋季增加5.6%,水分利用效率提高32.4%;此外,深松35 cm秸秆还田能促进玉米生产,较旋耕秸秆不还田的经济产量两年平均分别增产25.6%,生物产量提升33.3%,玉米氮、磷、钾养分吸收量分别提高49.6%、51.5%和37.6%.综上,深松35 cm秸秆还田能改善物理土壤特性,稳定耕层物理性状,提高0～100 cm土层剖面水分含量及春秋两季土壤平均贮水量,降低水分变异,是促进玉米水肥高效利用,实现高产的最优措施,为甘肃引黄灌区耕层构建技术的深入研究提供理论依据.
A field experiment was conducted to examine the effects of subsoiling 35 cm with maize straw returning,subsoiling 35 cm without maize straw returning,and rotary tillage without maize straw returning on soil compaction,soil bulk density,soil infiltration,soil water content in 0-100 cm depth,nutrients uptake and production of maize on sierozem in the Gansu Yellow River irrigated area in 2015-2017. Compared with subsoiling 35 cm without maize straw returning and rotary tillage without maize straw returning,subsoiling 35 cm with maize straw returning significantly decreased the soil compaction and soil density in 0-40 cm depth. Compared with that in 2015( before experiment),soil compaction and soil bulk density in subsoiling 35 cm with straw returning was decreased by 42. 6% and 7. 0%,respectively,after harvest in 2017. Compared with other treatments,subsoiling 35 cm with straw returning had the lowest variation of soil compaction( 6.1%)and soil bulk density( 3.2%) in 0-40 cm depth before sowing and after harvest in 2016 and 2017.The soil infiltration rate in subsoiling 35 cm with straw returning was significantly improved by33.6% compared with rotary tillage without maize straw returning. Subsoiling 35 cm with straw retention could significantly increase soil water content and decrease water variation in 0-100 cm soil depth in spring( before maize sowing) and autumn( after maize harvest). Compared with rotary tillage without maize straw returning,water storage in subsoiling 35 cm with straw retention was increased by 15. 5% and 5. 6% in spring and autumn,respectively. The water use efficiency was enhanced by 32. 4%. Furthermore,subsoiling 35 cm with straw retention could increase maize economic yield and biomass yield by 25.6% and 33.3%,compared with rotary tillage without straw retention. Subsoilng and straw retention could promote nutrient absorption,with N,P2O5 and K2O uptake increased by 49.6%,51.5% and 37.6%,compared with rotary tillage. Overall,our results suggested that subsoiling 35 cm straw retention could improve soil characteristics,stabilize the physical properties of the plough layer,increase soil water content in the 0-100 cm soil layer,and reduce water variation in spring and autumn. Consequently,it was the best management to promote the water and nutrient utilization of maize and achieve high yield. Our findings could provide theoretical basis for further research on the construction technology of the plough layer in Gansu irrigation area.
A field experiment was conducted to examine the effects of subsoiling 35 cm with maize straw returning,subsoiling 35 cm without maize straw returning,and rotary tillage without maize straw returning on soil compaction,soil bulk density,soil infiltration,soil water content in 0-100 cm depth,nutrients uptake and production of maize on sierozem in the Gansu Yellow River irrigated area in 2015-2017. Compared with subsoiling 35 cm without maize straw returning and rotary tillage without maize straw returning,subsoiling 35 cm with maize straw returning significantly decreased the soil compaction and soil density in 0-40 cm depth. Compared with that in 2015( before experiment),soil compaction and soil bulk density in subsoiling 35 cm with straw returning was decreased by 42. 6% and 7. 0%,respectively,after harvest in 2017. Compared with other treatments,subsoiling 35 cm with straw returning had the lowest variation of soil compaction( 6.1%)and soil bulk density( 3.2%) in 0-40 cm depth before sowing and after harvest in 2016 and 2017.The soil infiltration rate in subsoiling 35 cm with straw returning was significantly improved by33.6% compared with rotary tillage without maize straw returning. Subsoiling 35 cm with straw retention could significantly increase soil water content and decrease water variation in 0-100 cm soil depth in spring( before maize sowing) and autumn( after maize harvest). Compared with rotary tillage without maize straw returning,water storage in subsoiling 35 cm with straw retention was increased by 15. 5% and 5. 6% in spring and autumn,respectively. The water use efficiency was enhanced by 32. 4%. Furthermore,subsoiling 35 cm with straw retention could increase maize economic yield and biomass yield by 25.6% and 33.3%,compared with rotary tillage without straw retention. Subsoilng and straw retention could promote nutrient absorption,with N,P2O5 and K2O uptake increased by 49.6%,51.5% and 37.6%,compared with rotary tillage. Overall,our results suggested that subsoiling 35 cm straw retention could improve soil characteristics,stabilize the physical properties of the plough layer,increase soil water content in the 0-100 cm soil layer,and reduce water variation in spring and autumn. Consequently,it was the best management to promote the water and nutrient utilization of maize and achieve high yield. Our findings could provide theoretical basis for further research on the construction technology of the plough layer in Gansu irrigation area.
引文
[1]The Gansu Countryside Year book Editorial Committee(甘肃农村年鉴编委会).The Gansu Countryside 2011Yearbook.Beijing:China Statistics Press,2012(in Chinese)
[2]Yang S-C(杨思存),Feng H-C(逄焕成),Wang C-B(王成宝),et al.Characterization of soil salinization based on canonical correspondence analysis method in Gansu Yellow River irrigation district of Northwest China.Scientia Agricultura Sinica(中国农业科学),2014,47(1):100-110(in Chinese)
[3]The Gansu Soil Survey Office(甘肃省土壤普查办公室).Soils of Gansu.Beijing:China Agriculture Press,1993(in Chinese)
[4]Niu S-W(牛叔文),Chen Z-F(陈作芳).A Probe on Agricultural Region Development:A Study on Comprehensive Agriculture Exploitation in the Irrigation Area along the Yellow River of Gansu Province.Lanzhou:Lanzhou University Press,1998(in Chinese)
[5]Xiong S-G(熊顺贵).The Basis of Soil Science.Beijing:Chinese Agricultural Science and Technology Press,1996(in Chinese)
[6]Wang Z-Q(王志穷),Wang W-X(王维新),Li X(李霞),et al.Development status of subsoiling at home and abroad under conservation tillage.Journal of Agricultural Mechanization Research(农机化研究),2016,38(6):253-258(in Chinese)
[7]Song D-L(宋大利),Hou S-P(侯胜鹏),Wang X-B(王秀斌),et al.Nutrient resource quantity of crop straw and its potential of substituting.Journal of Plant Nutrition and Fertilizer(植物营养与肥料学报),2018,24(1):1-21(in Chinese)
[8]Li M-D(李明德),Wu H-Y(吴海勇),Nie J(聂军),et al.Utilities of straw and wastes of straw recycling returning on rice planting.Scientia Agricultura Sinica(中国农业科学),2010,43(17):3572-3579(in Chinese)
[9]Pathak H,Singh R,Bhatia A,et al.Recycling of rice straw to improve wheat yield and soil fertility and reduce atmospheric pollution.Paddy&Water Environment,2006,4:111-117
[10]Wang Y-H(王育红),Yao Y-Q(姚宇卿),Lyu J-J(吕军杰),et al.Ecological effect of subsoiling high stubble on the winter wheat in sloping land of western Henan.Chinese Journal of Eco-Agriculture(中国生态农业学报),2004,12(2):146-148(in Chinese)
[11]Zhang F-J(张凤杰),Sun J-Y(孙继颖),Gao J-L(髙聚林),et al.Response of spring maize root morphological characteristics and soil physicochemical properties to chiseling depth.Journal of Maize Sciences(玉米科学),2016,24(6):88-96(in Chinese)
[12]Xiao J-B(肖继兵),Sun Z-X(孙占祥),Yang J-T(杨久廷),et al.Effect of subsoiling on soil water and crop yield in semi-arid area.Chinese Journal of Soil Science(土壤通报),2011,42(3):709-714(in Chinese)
[13]Ji Q(姬强),Sun H-Y(孙汉印),Wang X-D(王旭东),et al.Impact of different tillage practices on soil organic carbon and water use efficiency under continuous wheat-maize binary cropping system.Chinese Journal of Applied Ecology(应用生态学报),2014,25(4):1029-1035(in Chinese)
[14]Zhao Y-L(赵亚丽),Xue Z-W(薛志伟),Guo H-B(郭海斌),et al.Effects of tillage and straw returning on water consumption characteristics and water use efficiency in the winter wheat and summer maize rotation system.Scientia Agricultura Sinica(中国农业科学),2014,47(17):3359-3371(in Chinese)
[15]Shi L(石磊),Xu M-X(许明祥),Dong L-R(董丽茹),et al.Evaluation of soil physical obstacles on cropland in Shaanxi Province.Agricultural Research in the Arid Areas(干旱地区农业研究),2016,34(3):46-53(in Chinese)
[16]Nawaz MF,Bourrie G,Trolard F.Soil compaction impact and modeling:A review.Agronomy for Sustainable Development,2013,33:291-309
[17]Bao S-D(鲍士旦).Soil and Agricultural Chemistry Analysis.3rd Ed.Beijing:China Agriculture Press,2005(in Chinese)
[18]Du T-S(杜太生),Kang S-Z(康绍忠),Hu X-T(胡笑涛),et al.Effect of alternate partial root-zone drip irrigation on yield and water use efficiency of cotton.Scientia Agricultura Sinica(中国农业科学),2005,38(10):2061-2068(in Chinese)
[19]Zheng H-B(郑洪兵),Qi H(齐华),Liu W-R(刘武仁),et al.Discussion on the present situation,existing problems and reasonable plough layer construction of corn field plough layer.Tillage and Cultivation(耕作与栽培),2014,39(5):39-42(in Chinese)
[20]An F-H(安丰华),Wang Z-C(王志春),Yang F(杨帆),et al.The research progress of straw returning.Soil and Crop(土壤与作物),2015,4(2):57-63(in Chinese)
[21]Deng Z-H(邓智惠),Liu X-L(刘新梁),Li C-Y(李春阳),et al.Effects of subsoiling and straw returning on surface soil physical properties and maize yield.Crops(作物杂志),2015(6):117-120(in Chinese)
[22]Zhang L(张丽),Zhang Z-D(张正东),Guo Z-Y(郭正宇),et al.Effects of subsoiling tillage and straw returning to field on soil physical properties.Bulletin of Soil and Water Conservation(水土保持通报),2015,35(1):102-117(in Chinese)
[23]Xu Y-G(徐永刚),Ma Q(马强),Zhou H(周桦),et al.Effects of straw returning and deep loosening on soil physical and chemical properties and maize yield.Chinese Journal of Soil Science(土壤通报),2015,46(2):428-432(in Chinese)
[24]He J(何进),Li H-W(李洪文),Gao H-W(高焕文).Subsoiling effect and economic benefit under conservation tillage mode in Northern China.Transactions of the Chinese Society of Agricultural Engineering(农业工程学报),2006,22(10):62-67(in Chinese)
[25]Fu G-Z(付国占),Li C-H(李潮海),Wang J-Z(王俊忠),et al.Effects of stubble mulch and tillage managements on soil physical properties and water use efficiency of summer maize.Transactions of the Chinese Society of Agricultural Engineering(农业工程学报),2005,21(1):52-56(in Chinese)
[26]Heuer H,TomanovO,Koch HJ,et al.Subsoil properties and cereal growth as affected by a single pass of heavy machinery and two tillage systems on a Luvisol.Journal of Plant Nutrition and Soil Science,2008,171:580-590
[27]Li R(李荣),Hou X-Q(侯贤清).Effects of different ground surface mulch under subsoiling on potato yield and water use efficiency.Transactions of the Chinese Society of Agricultural Engineering(农业工程学报),2015,31(20):115-123(in Chinese)
[28]Liu D(刘丹),Zhang X(张霞),Li J(李军),et al.Effects of different tillage patterns on soil properties,maize yield and water use efficiency in Weibei Highland.Chinese Journal of Applied Ecology(应用生态学报),2018,29(2):573-582(in Chinese)
[29]Zheng C-Y(郑成岩),Cui S-M(崔世明),Wang D(王东),et al.Effects of soil tillage practice on dry matter production and water use efficiency in wheat.Acta Agronomica Sinica(作物学报),2011,37(8):1432-1440(in Chinese)
[30]Huang G-B(黄高宝),Guo Q-Y(郭清毅),Zhang R-Z(张仁陟),et al.Effects of conservation tillage on soil moisture and crop yield in a phased rotation system with spring wheat and field pea in dryland.Acta Ecologica Sinica(生态学报),2006,26(4):1176-1185(in Chinese)
[31]Zhao Y-L(赵亚丽),Guo H-B(郭海斌),Xue Z-W(薛志伟),et al.Effects of tillage and straw returning on biomass and water use efficiency in a winter wheat and summer maize rotation system.Acta Agronomica Sinica(作物学报),2014,40(10):1797-1807(in Chinese)
[32]Sharma AR,Singh R,Dhyani SK,et al.Moisture conservation and nitrogen recycling through legume mulching in rain-fed maize(Zea mays)-wheat(Triticum aestivum)cropping system.Nutrient Cycling in Agroecosystems,2010,87:187-197
[33]Huang M(黄明),Wu J-Z(吴金芝),Li Y-J(李友军),et al.Effects of tillage pattern on the flag leaf senescence and grain yield of winter wheat under dry farming.Chinese Journal of Applied Ecology(应用生态学报),2009,20(6):1355-1361(in Chinese)
[34]Zhang R-F(张瑞富),Yang H-S(杨恒山),Gao J-L(高聚林),et al.Subsoiling facilitating accumulation and transportation of dry matter and phosphorus of spring maize.Transactions of the Chinese Society of Agricultural Engineering(农业工程学报),2016,32(19):106-112(in Chinese)
[35]Guo J-M(郭家萌),Liu Z-C(刘振朝),Gao Q(高强),et al.Effects of subsoiling on yield and nutrient uptake of maize.Journal of Soil and Water Conservation(水土保持学报),2016,30(2):249-254(in Chinese)
[36]Huang T-M(黄婷苗),Zheng X-F(郑险峰),Hou Y-Y(侯仰毅),et al.Yield and N,P and K uptake and utilization of winter wheat affected by straw return to soil.Journal of Plant Nutrition and Fertilizer(植物营养与肥料学报),2015,21(4):853-863(in Chinese)
[37]He H-X(何红霞),Wang Z-H(王朝辉),Bao M(包明),et al.Effects of cultivation patterns on wheat yield and grain nutrient concentration in dryland.Chinese Journal of Applied Ecology(应用生态学报),2018,29(3):818-826(in Chinese)
[2]Yang S-C(杨思存),Feng H-C(逄焕成),Wang C-B(王成宝),et al.Characterization of soil salinization based on canonical correspondence analysis method in Gansu Yellow River irrigation district of Northwest China.Scientia Agricultura Sinica(中国农业科学),2014,47(1):100-110(in Chinese)
[3]The Gansu Soil Survey Office(甘肃省土壤普查办公室).Soils of Gansu.Beijing:China Agriculture Press,1993(in Chinese)
[4]Niu S-W(牛叔文),Chen Z-F(陈作芳).A Probe on Agricultural Region Development:A Study on Comprehensive Agriculture Exploitation in the Irrigation Area along the Yellow River of Gansu Province.Lanzhou:Lanzhou University Press,1998(in Chinese)
[5]Xiong S-G(熊顺贵).The Basis of Soil Science.Beijing:Chinese Agricultural Science and Technology Press,1996(in Chinese)
[6]Wang Z-Q(王志穷),Wang W-X(王维新),Li X(李霞),et al.Development status of subsoiling at home and abroad under conservation tillage.Journal of Agricultural Mechanization Research(农机化研究),2016,38(6):253-258(in Chinese)
[7]Song D-L(宋大利),Hou S-P(侯胜鹏),Wang X-B(王秀斌),et al.Nutrient resource quantity of crop straw and its potential of substituting.Journal of Plant Nutrition and Fertilizer(植物营养与肥料学报),2018,24(1):1-21(in Chinese)
[8]Li M-D(李明德),Wu H-Y(吴海勇),Nie J(聂军),et al.Utilities of straw and wastes of straw recycling returning on rice planting.Scientia Agricultura Sinica(中国农业科学),2010,43(17):3572-3579(in Chinese)
[9]Pathak H,Singh R,Bhatia A,et al.Recycling of rice straw to improve wheat yield and soil fertility and reduce atmospheric pollution.Paddy&Water Environment,2006,4:111-117
[10]Wang Y-H(王育红),Yao Y-Q(姚宇卿),Lyu J-J(吕军杰),et al.Ecological effect of subsoiling high stubble on the winter wheat in sloping land of western Henan.Chinese Journal of Eco-Agriculture(中国生态农业学报),2004,12(2):146-148(in Chinese)
[11]Zhang F-J(张凤杰),Sun J-Y(孙继颖),Gao J-L(髙聚林),et al.Response of spring maize root morphological characteristics and soil physicochemical properties to chiseling depth.Journal of Maize Sciences(玉米科学),2016,24(6):88-96(in Chinese)
[12]Xiao J-B(肖继兵),Sun Z-X(孙占祥),Yang J-T(杨久廷),et al.Effect of subsoiling on soil water and crop yield in semi-arid area.Chinese Journal of Soil Science(土壤通报),2011,42(3):709-714(in Chinese)
[13]Ji Q(姬强),Sun H-Y(孙汉印),Wang X-D(王旭东),et al.Impact of different tillage practices on soil organic carbon and water use efficiency under continuous wheat-maize binary cropping system.Chinese Journal of Applied Ecology(应用生态学报),2014,25(4):1029-1035(in Chinese)
[14]Zhao Y-L(赵亚丽),Xue Z-W(薛志伟),Guo H-B(郭海斌),et al.Effects of tillage and straw returning on water consumption characteristics and water use efficiency in the winter wheat and summer maize rotation system.Scientia Agricultura Sinica(中国农业科学),2014,47(17):3359-3371(in Chinese)
[15]Shi L(石磊),Xu M-X(许明祥),Dong L-R(董丽茹),et al.Evaluation of soil physical obstacles on cropland in Shaanxi Province.Agricultural Research in the Arid Areas(干旱地区农业研究),2016,34(3):46-53(in Chinese)
[16]Nawaz MF,Bourrie G,Trolard F.Soil compaction impact and modeling:A review.Agronomy for Sustainable Development,2013,33:291-309
[17]Bao S-D(鲍士旦).Soil and Agricultural Chemistry Analysis.3rd Ed.Beijing:China Agriculture Press,2005(in Chinese)
[18]Du T-S(杜太生),Kang S-Z(康绍忠),Hu X-T(胡笑涛),et al.Effect of alternate partial root-zone drip irrigation on yield and water use efficiency of cotton.Scientia Agricultura Sinica(中国农业科学),2005,38(10):2061-2068(in Chinese)
[19]Zheng H-B(郑洪兵),Qi H(齐华),Liu W-R(刘武仁),et al.Discussion on the present situation,existing problems and reasonable plough layer construction of corn field plough layer.Tillage and Cultivation(耕作与栽培),2014,39(5):39-42(in Chinese)
[20]An F-H(安丰华),Wang Z-C(王志春),Yang F(杨帆),et al.The research progress of straw returning.Soil and Crop(土壤与作物),2015,4(2):57-63(in Chinese)
[21]Deng Z-H(邓智惠),Liu X-L(刘新梁),Li C-Y(李春阳),et al.Effects of subsoiling and straw returning on surface soil physical properties and maize yield.Crops(作物杂志),2015(6):117-120(in Chinese)
[22]Zhang L(张丽),Zhang Z-D(张正东),Guo Z-Y(郭正宇),et al.Effects of subsoiling tillage and straw returning to field on soil physical properties.Bulletin of Soil and Water Conservation(水土保持通报),2015,35(1):102-117(in Chinese)
[23]Xu Y-G(徐永刚),Ma Q(马强),Zhou H(周桦),et al.Effects of straw returning and deep loosening on soil physical and chemical properties and maize yield.Chinese Journal of Soil Science(土壤通报),2015,46(2):428-432(in Chinese)
[24]He J(何进),Li H-W(李洪文),Gao H-W(高焕文).Subsoiling effect and economic benefit under conservation tillage mode in Northern China.Transactions of the Chinese Society of Agricultural Engineering(农业工程学报),2006,22(10):62-67(in Chinese)
[25]Fu G-Z(付国占),Li C-H(李潮海),Wang J-Z(王俊忠),et al.Effects of stubble mulch and tillage managements on soil physical properties and water use efficiency of summer maize.Transactions of the Chinese Society of Agricultural Engineering(农业工程学报),2005,21(1):52-56(in Chinese)
[26]Heuer H,TomanovO,Koch HJ,et al.Subsoil properties and cereal growth as affected by a single pass of heavy machinery and two tillage systems on a Luvisol.Journal of Plant Nutrition and Soil Science,2008,171:580-590
[27]Li R(李荣),Hou X-Q(侯贤清).Effects of different ground surface mulch under subsoiling on potato yield and water use efficiency.Transactions of the Chinese Society of Agricultural Engineering(农业工程学报),2015,31(20):115-123(in Chinese)
[28]Liu D(刘丹),Zhang X(张霞),Li J(李军),et al.Effects of different tillage patterns on soil properties,maize yield and water use efficiency in Weibei Highland.Chinese Journal of Applied Ecology(应用生态学报),2018,29(2):573-582(in Chinese)
[29]Zheng C-Y(郑成岩),Cui S-M(崔世明),Wang D(王东),et al.Effects of soil tillage practice on dry matter production and water use efficiency in wheat.Acta Agronomica Sinica(作物学报),2011,37(8):1432-1440(in Chinese)
[30]Huang G-B(黄高宝),Guo Q-Y(郭清毅),Zhang R-Z(张仁陟),et al.Effects of conservation tillage on soil moisture and crop yield in a phased rotation system with spring wheat and field pea in dryland.Acta Ecologica Sinica(生态学报),2006,26(4):1176-1185(in Chinese)
[31]Zhao Y-L(赵亚丽),Guo H-B(郭海斌),Xue Z-W(薛志伟),et al.Effects of tillage and straw returning on biomass and water use efficiency in a winter wheat and summer maize rotation system.Acta Agronomica Sinica(作物学报),2014,40(10):1797-1807(in Chinese)
[32]Sharma AR,Singh R,Dhyani SK,et al.Moisture conservation and nitrogen recycling through legume mulching in rain-fed maize(Zea mays)-wheat(Triticum aestivum)cropping system.Nutrient Cycling in Agroecosystems,2010,87:187-197
[33]Huang M(黄明),Wu J-Z(吴金芝),Li Y-J(李友军),et al.Effects of tillage pattern on the flag leaf senescence and grain yield of winter wheat under dry farming.Chinese Journal of Applied Ecology(应用生态学报),2009,20(6):1355-1361(in Chinese)
[34]Zhang R-F(张瑞富),Yang H-S(杨恒山),Gao J-L(高聚林),et al.Subsoiling facilitating accumulation and transportation of dry matter and phosphorus of spring maize.Transactions of the Chinese Society of Agricultural Engineering(农业工程学报),2016,32(19):106-112(in Chinese)
[35]Guo J-M(郭家萌),Liu Z-C(刘振朝),Gao Q(高强),et al.Effects of subsoiling on yield and nutrient uptake of maize.Journal of Soil and Water Conservation(水土保持学报),2016,30(2):249-254(in Chinese)
[36]Huang T-M(黄婷苗),Zheng X-F(郑险峰),Hou Y-Y(侯仰毅),et al.Yield and N,P and K uptake and utilization of winter wheat affected by straw return to soil.Journal of Plant Nutrition and Fertilizer(植物营养与肥料学报),2015,21(4):853-863(in Chinese)
[37]He H-X(何红霞),Wang Z-H(王朝辉),Bao M(包明),et al.Effects of cultivation patterns on wheat yield and grain nutrient concentration in dryland.Chinese Journal of Applied Ecology(应用生态学报),2018,29(3):818-826(in Chinese)