为探明双季稻区不同土壤耕作模式下双季水稻生理特性、干物质积累及产量的变化,本文以双季稻–紫云英大田定位试验为平台,设双季水稻翻耕+秸秆还田(CT)、双季水稻旋耕+秸秆还田(RT)、双季水稻免耕+秸秆还田(NT)、双季水稻旋耕+秸秆不还...为探明双季稻区不同土壤耕作模式下双季水稻生理特性、干物质积累及产量的变化,本文以双季稻–紫云英大田定位试验为平台,设双季水稻翻耕+秸秆还田(CT)、双季水稻旋耕+秸秆还田(RT)、双季水稻免耕+秸秆还田(NT)、双季水稻旋耕+秸秆不还田(RTO,对照)4种土壤耕作处理,于2016—2017年取样,系统分析了不同处理对双季水稻植株叶片保护性酶活性、光合特性、干物质积累及产量的影响。研究结果表明,早、晚稻各个主要生育时期CT和RT处理植株叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性均显著高于RTO处理(P<0.05),而叶片丙二醛(MDA)含量均显著低于RTO处理(P<0.05)。CT处理植株叶片的净光合速率(Pn)、蒸腾速率(Tr)和叶片气孔导度(Gs)均显著高于RTO处理(P<0.05),均表现为CT>RT>NT>RTO。CT和RT处理水稻植株物质生产能力强,干物质积累多,而且在各器官间的分配合理。2个年份的早稻产量均以CT处理最高,均显著高于RTO处理(P<0.05),比RTO处理增加731.1~733.3 kg hm–2;晚稻产量均以CT处理为最高,均显著高于RTO处理(P<0.05),比RTO处理增加582.5~717.6 kg hm–2。总之,土壤翻耕、旋耕结合秸秆还田处理有利于提高双季水稻叶片保护性酶活性、光合特性和干物质积累量,为水稻高产奠定了生理和生物学基础。展开更多
The functional diversity of rhizosphere microflora which is also known as the “microbial community” is a sensitive indicator of soil quality subject to the type of winter cover crop and straw returning.In order to e...The functional diversity of rhizosphere microflora which is also known as the “microbial community” is a sensitive indicator of soil quality subject to the type of winter cover crop and straw returning.In order to evaluate the effects of different winter cover crops and returning patterns on the functional diversity of rhizosphere microflora in double-crop rice paddies,we designed five winter cover crops and straw returning combinations to analyze their effects on the functional diversity of rhizosphere microflora in rice paddies: ryegrass (Lolium multiflorumL.)–double-crop rice (Ry),milk vetch (Astragalus sinicus L.)–double-crop rice (Mv),Rape (Brassica napus L.)–Double-crop rice (Ra), Potato (Solanum tuberosum L.)–double-crop rice (Po),and winter fallow–doublecrop rice (CK,the control).In this paper,the average well color development (AWCD) in Biolog-GN plates indicated the capacity for carbon utilization by the rhizosphere microbial community.We analyzed the rhizosphere microbial community functional diversity of the paddy soils with the above five treatments by using the Biolog-GN system.The results showed that applications of winter cover crop and straw returning caused high increases in AWCD compared with CK,and the AWCD values for samples with Po treatment was greater than those with Ry and CK treatments at the early and late rice maturity stages. It was concluded that applications of winter cover crop and straw returning can cause changes in the carbon utilization efficiency of rhizosphere microflora.There were differences in the genetic diversity of the rhizosphere microflora among different treatments at the maturity stage of early and late rice.The richness,Shannon,and McIntosh Index under different winter cover crop and straw returning treatments were significantly different.The highest indexes were observed in the Po treatment and the lowest in the CK at the maturity stage of early and late rice.The richness, Shannon,and McIntosh Index under different treatments ranked in descending order is as follows: Po>Ra>Mv>Ry>CK.Principal Component Analysis (PCA) of substrate reactions were conducted in this research.The results indicated that the pattern of carbon source utilization varied with winter cover crop treatments,and that carbohydrates and amino acids were the main carbon sources of rhizosphere microorganisms.To conclude,the application of winter cover crop and straw returning to paddy fields could significantly increase the carbon source utilization, species richness,and species evenness of rhizosphere microflora in double-crop rice paddies.展开更多
From 2017 to 2018,the effects of winter planting of milk vetch on yield and partial productivity of nitrogen fertilizer of machine-transplanted double-cropping rice under straw returning were studied in Ningxiang city...From 2017 to 2018,the effects of winter planting of milk vetch on yield and partial productivity of nitrogen fertilizer of machine-transplanted double-cropping rice under straw returning were studied in Ningxiang city,Hunan Province.The results showed that the dry matter accumulation,effective panicle,yield and partial productivity of nitrogen fertilizer in the stem,leaf,panicle and aboveground parts of early and late rice treated with winter planting milk vetch and straw returning were signi ficantly higher than those treated with straw returning only.Among them,the effective panicles of early and late rice increased by 2.58%,3.18%(2017)and 5.22%,6.32%(2018),respectively.Yield increased by 11.85%,10.07%(2017)and 12.42%,10.92%(2018),annual partial productivity of nitrogen fertilizer increased by 10.90%(2017)and 11.66%(2018),respectively.In conclusion,winter planting milk vetch under straw returning is beneficial to increase dry matter accumulation,rice yield and partial productivity of nitrogen fertilizer in mechanized double cropping rice.展开更多
施肥措施与稻田生态系统净碳汇效应、经济收益的关系密切。本研究以长期(35年)定位施肥试验田为平台,分析了单独施用化肥(MF)、秸秆还田+化肥(RF)、30%有机肥+70%化肥(OM)和无肥对照(CK)4种不同施肥模式对我国南方双季稻田耕层土壤固碳...施肥措施与稻田生态系统净碳汇效应、经济收益的关系密切。本研究以长期(35年)定位施肥试验田为平台,分析了单独施用化肥(MF)、秸秆还田+化肥(RF)、30%有机肥+70%化肥(OM)和无肥对照(CK)4种不同施肥模式对我国南方双季稻田耕层土壤固碳速率、碳密度、年碳汇平衡和经济收益的影响。研究表明:不同施肥处理双季稻田耕层土壤碳库变化范围为216.02~866.74 kg·hm^(-2)·a^(-1),OM处理土壤碳年变化量显著高于MF、RF和CK处理;双季稻田土壤固碳速率为51.5~650.7 kg·hm^(-2)·a^(-1),表土碳密度为55.64~78.42 t·hm^(-2),各施肥处理高低顺序均为OM>RF>MF>CK。各施肥处理双季稻田生态系统水稻的碳吸收为4.42~9.32 t C·hm^(-2)·a^(-1),其高低顺序为OM>RF>MF>CK;与MF处理相比,OM和RF处理稻田土壤净碳汇量分别提高了27.6%和13.6%。各施肥处理双季稻田生态系统的碳成本物质投入变化范围为1.49~2.17 t C·hm^(-2)·a^(-1),年经济收益变化范围为1.30×10^(3)~7.83×10^(3)元·hm^(-2)·a^(-1),其高低顺序为RF>OM>MF>CK;OM、RF和MF处理双季稻田生态系统经济效益的净收益均显著高于CK处理。总之,长期施用有机肥、秸秆还田配施化肥措施均有利于增加双季稻田土壤固碳速率、碳汇效应和经济收益,是提高南方双季稻田土壤有机碳贮量的施肥模式。展开更多
文摘为探明双季稻区不同土壤耕作模式下双季水稻生理特性、干物质积累及产量的变化,本文以双季稻–紫云英大田定位试验为平台,设双季水稻翻耕+秸秆还田(CT)、双季水稻旋耕+秸秆还田(RT)、双季水稻免耕+秸秆还田(NT)、双季水稻旋耕+秸秆不还田(RTO,对照)4种土壤耕作处理,于2016—2017年取样,系统分析了不同处理对双季水稻植株叶片保护性酶活性、光合特性、干物质积累及产量的影响。研究结果表明,早、晚稻各个主要生育时期CT和RT处理植株叶片超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性均显著高于RTO处理(P<0.05),而叶片丙二醛(MDA)含量均显著低于RTO处理(P<0.05)。CT处理植株叶片的净光合速率(Pn)、蒸腾速率(Tr)和叶片气孔导度(Gs)均显著高于RTO处理(P<0.05),均表现为CT>RT>NT>RTO。CT和RT处理水稻植株物质生产能力强,干物质积累多,而且在各器官间的分配合理。2个年份的早稻产量均以CT处理最高,均显著高于RTO处理(P<0.05),比RTO处理增加731.1~733.3 kg hm–2;晚稻产量均以CT处理为最高,均显著高于RTO处理(P<0.05),比RTO处理增加582.5~717.6 kg hm–2。总之,土壤翻耕、旋耕结合秸秆还田处理有利于提高双季水稻叶片保护性酶活性、光合特性和干物质积累量,为水稻高产奠定了生理和生物学基础。
文摘The functional diversity of rhizosphere microflora which is also known as the “microbial community” is a sensitive indicator of soil quality subject to the type of winter cover crop and straw returning.In order to evaluate the effects of different winter cover crops and returning patterns on the functional diversity of rhizosphere microflora in double-crop rice paddies,we designed five winter cover crops and straw returning combinations to analyze their effects on the functional diversity of rhizosphere microflora in rice paddies: ryegrass (Lolium multiflorumL.)–double-crop rice (Ry),milk vetch (Astragalus sinicus L.)–double-crop rice (Mv),Rape (Brassica napus L.)–Double-crop rice (Ra), Potato (Solanum tuberosum L.)–double-crop rice (Po),and winter fallow–doublecrop rice (CK,the control).In this paper,the average well color development (AWCD) in Biolog-GN plates indicated the capacity for carbon utilization by the rhizosphere microbial community.We analyzed the rhizosphere microbial community functional diversity of the paddy soils with the above five treatments by using the Biolog-GN system.The results showed that applications of winter cover crop and straw returning caused high increases in AWCD compared with CK,and the AWCD values for samples with Po treatment was greater than those with Ry and CK treatments at the early and late rice maturity stages. It was concluded that applications of winter cover crop and straw returning can cause changes in the carbon utilization efficiency of rhizosphere microflora.There were differences in the genetic diversity of the rhizosphere microflora among different treatments at the maturity stage of early and late rice.The richness,Shannon,and McIntosh Index under different winter cover crop and straw returning treatments were significantly different.The highest indexes were observed in the Po treatment and the lowest in the CK at the maturity stage of early and late rice.The richness, Shannon,and McIntosh Index under different treatments ranked in descending order is as follows: Po>Ra>Mv>Ry>CK.Principal Component Analysis (PCA) of substrate reactions were conducted in this research.The results indicated that the pattern of carbon source utilization varied with winter cover crop treatments,and that carbohydrates and amino acids were the main carbon sources of rhizosphere microorganisms.To conclude,the application of winter cover crop and straw returning to paddy fields could significantly increase the carbon source utilization, species richness,and species evenness of rhizosphere microflora in double-crop rice paddies.
文摘From 2017 to 2018,the effects of winter planting of milk vetch on yield and partial productivity of nitrogen fertilizer of machine-transplanted double-cropping rice under straw returning were studied in Ningxiang city,Hunan Province.The results showed that the dry matter accumulation,effective panicle,yield and partial productivity of nitrogen fertilizer in the stem,leaf,panicle and aboveground parts of early and late rice treated with winter planting milk vetch and straw returning were signi ficantly higher than those treated with straw returning only.Among them,the effective panicles of early and late rice increased by 2.58%,3.18%(2017)and 5.22%,6.32%(2018),respectively.Yield increased by 11.85%,10.07%(2017)and 12.42%,10.92%(2018),annual partial productivity of nitrogen fertilizer increased by 10.90%(2017)and 11.66%(2018),respectively.In conclusion,winter planting milk vetch under straw returning is beneficial to increase dry matter accumulation,rice yield and partial productivity of nitrogen fertilizer in mechanized double cropping rice.
文摘施肥措施与稻田生态系统净碳汇效应、经济收益的关系密切。本研究以长期(35年)定位施肥试验田为平台,分析了单独施用化肥(MF)、秸秆还田+化肥(RF)、30%有机肥+70%化肥(OM)和无肥对照(CK)4种不同施肥模式对我国南方双季稻田耕层土壤固碳速率、碳密度、年碳汇平衡和经济收益的影响。研究表明:不同施肥处理双季稻田耕层土壤碳库变化范围为216.02~866.74 kg·hm^(-2)·a^(-1),OM处理土壤碳年变化量显著高于MF、RF和CK处理;双季稻田土壤固碳速率为51.5~650.7 kg·hm^(-2)·a^(-1),表土碳密度为55.64~78.42 t·hm^(-2),各施肥处理高低顺序均为OM>RF>MF>CK。各施肥处理双季稻田生态系统水稻的碳吸收为4.42~9.32 t C·hm^(-2)·a^(-1),其高低顺序为OM>RF>MF>CK;与MF处理相比,OM和RF处理稻田土壤净碳汇量分别提高了27.6%和13.6%。各施肥处理双季稻田生态系统的碳成本物质投入变化范围为1.49~2.17 t C·hm^(-2)·a^(-1),年经济收益变化范围为1.30×10^(3)~7.83×10^(3)元·hm^(-2)·a^(-1),其高低顺序为RF>OM>MF>CK;OM、RF和MF处理双季稻田生态系统经济效益的净收益均显著高于CK处理。总之,长期施用有机肥、秸秆还田配施化肥措施均有利于增加双季稻田土壤固碳速率、碳汇效应和经济收益,是提高南方双季稻田土壤有机碳贮量的施肥模式。