In wetland ecosystem, nitrogen along with other elements and its management is most imperative for the production of so many aquatic food, non-food and beneficial medicinal plants and for the improvement of soil and w...In wetland ecosystem, nitrogen along with other elements and its management is most imperative for the production of so many aquatic food, non-food and beneficial medicinal plants and for the improvement of soil and water characteristics. With great significant importance of INM (integrated nutrient management) as sources, emphasizing on management on nitrogen as a key element and its divergence, a case study was undertaken on such aquatic food crops (starch and protein-rich, most popular and remunerative) in the farmers' field of low-lying randomized block design, where, three important aquatic food crops (water chestnut (Trapa bispinosa Roxb.), makhana (Eurya/e ferox Salisb.) and water lily (Nymphaea spp.) as major factor and eleven combinations of organic and inorganic sources of nutrients as sub-factor was considered in the experiment. It revealed from the results that the production of fresh kernels or nuts of water chestnut (8.57 t ha-1), matured nut yield of makhana (3.06 t ha-1) and flower stalks of water-lily as vegetables (6.38 t ha-1) including its nutritional quality (starch, protein, sugar and minerals) was remarkably influenced with the application of both organic (neem oilcake @ 0.2 t ha-1) and inorganic sources (NPK @ 30:20:20 kg ha-1 along with spraying of NPK @ 0.5% each over crop canopy at 20 days interval after transplanting) than the other INM combinations applied to the crops. Among the crops, highest WCYE (water chestnut yield equivalence) exhibited in makhana due to its high price of popped-form in the country, which is being exported to other countries at now. Sole application of both (organic and inorganic sources) with lower range did not produce any significant outcome from the study and exhibited lower value for all the crops.Besides production of food crops, INM also greatly influenced the soil and water characterization and it was favourably reflected in this study. The physico-chemical characteristics of soil (textural class, pH, organic carbon, organic matter, ammoniacal nitrogen, nitrate nitrogen, available nitrogen, phosphorus and potassium) are most important and contributed a significant improvement due to cultivation of these aquatic crops. Analysis of such wet bodies represented the water characteristics (pH, BOD, COD, CO3-, HCO3-, NO3-N, SO4-S and Cl-) were most responsive,adaptable and quite favourable for the cultivation of these crops in this vast waste unused wetlands for the mankind without any environmental degradation.展开更多
Biochar amendment and substituting chemical fertilizers with organic manure(organic substitution)have been widely reported to increase crop production and decrease reactive nitrogen(Nr)loss including nitrous oxide(N_(...Biochar amendment and substituting chemical fertilizers with organic manure(organic substitution)have been widely reported to increase crop production and decrease reactive nitrogen(Nr)loss including nitrous oxide(N_(2)O),nitric oxide(NO),and ammonia(NH3)emissions,and N runoff and leaching.However,few comprehensive evalua-tions have been performed on the environmental and economic aspects of biochar amendment or organic sub-stitution.Here,we studied the comprehensive effects of biochar amendment,organic substitution,and biochar amendment combined with organic substitution on crop production,Nr loss,and net ecosystem economic benefit(NEEB)in intensive vegetable production by integrating life-cycle assessment for Nr footprints,empirical models for NH3 volatilization and N runoff and leaching derived from peer-reviewed publications and validated by the current measurements and direct field measurement for N_(2)O and NO emissions during 5 consecutive years of vegetable crop rotations.Five fertilization treatments were applied(SN:synthetic fertilizer application;SNB:SN plus 20 t ha^(−1)biochar amendment;SNM:substituting 50%of chemical N fertilizer with organic manure;SNMB:SNM plus 20 t ha^(−1)biochar amendment;and CK:no fertilizer or biochar addition).Compared with the SN,the SNB increased vegetable yield(28.4%,p<0.05;interannually varying from−10 to 74.9%)and nitrogen use efficiency(29.2%,interannually varying from−39.7 to 150.4%),and decreased field Nr loss(45.4%,p<0.01;interannually varying from−40.3 to 78.4%),and thus improved NEEB by 7.1%;meanwhile,the SNM increased vegetable yield(11.6%,interannually varying from−5.4 to 27.1%)and nitrogen use efficiency(45.7%,p<0.05;interannually varying from 2.3 to 154%),reduced field Nr loss(34.9%,p<0.01;interannually varying from 8.4-39.0%),and thus improved NEEB by 17.8%(p<0.05)compared to the SN,being 56.0×10^(3)Chinese Yuan(CNY)ha^(−1)crop^(−1).Due to the high foreground Nr loss during organic manure production and high input costs of biochar production,the SNMB decreased the NEEB by 8.0%as compared to the SN.Moreover,the SNB and SNM improved vegetable qualities by increasing protein,soluble sugar,and vitamin C contents while decreasing nitrate content(p<0.05).Therefore,single application of biochar amendment or organic substitution would achieve better NEEB and product quality in vegetable production.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In wetland ecosystem, nitrogen along with other elements and its management is most imperative for the production of so many aquatic food, non-food and beneficial medicinal plants and for the improvement of soil and water characteristics. With great significant importance of INM (integrated nutrient management) as sources, emphasizing on management on nitrogen as a key element and its divergence, a case study was undertaken on such aquatic food crops (starch and protein-rich, most popular and remunerative) in the farmers' field of low-lying randomized block design, where, three important aquatic food crops (water chestnut (Trapa bispinosa Roxb.), makhana (Eurya/e ferox Salisb.) and water lily (Nymphaea spp.) as major factor and eleven combinations of organic and inorganic sources of nutrients as sub-factor was considered in the experiment. It revealed from the results that the production of fresh kernels or nuts of water chestnut (8.57 t ha-1), matured nut yield of makhana (3.06 t ha-1) and flower stalks of water-lily as vegetables (6.38 t ha-1) including its nutritional quality (starch, protein, sugar and minerals) was remarkably influenced with the application of both organic (neem oilcake @ 0.2 t ha-1) and inorganic sources (NPK @ 30:20:20 kg ha-1 along with spraying of NPK @ 0.5% each over crop canopy at 20 days interval after transplanting) than the other INM combinations applied to the crops. Among the crops, highest WCYE (water chestnut yield equivalence) exhibited in makhana due to its high price of popped-form in the country, which is being exported to other countries at now. Sole application of both (organic and inorganic sources) with lower range did not produce any significant outcome from the study and exhibited lower value for all the crops.Besides production of food crops, INM also greatly influenced the soil and water characterization and it was favourably reflected in this study. The physico-chemical characteristics of soil (textural class, pH, organic carbon, organic matter, ammoniacal nitrogen, nitrate nitrogen, available nitrogen, phosphorus and potassium) are most important and contributed a significant improvement due to cultivation of these aquatic crops. Analysis of such wet bodies represented the water characteristics (pH, BOD, COD, CO3-, HCO3-, NO3-N, SO4-S and Cl-) were most responsive,adaptable and quite favourable for the cultivation of these crops in this vast waste unused wetlands for the mankind without any environmental degradation.
基金the National Natural Science Foundation of China(41977078,32001213)the Postgraduate Research&Practice Innovation Program of Jiangsu Province,China(KYCX21_0618,KYCX20_0591).
文摘Biochar amendment and substituting chemical fertilizers with organic manure(organic substitution)have been widely reported to increase crop production and decrease reactive nitrogen(Nr)loss including nitrous oxide(N_(2)O),nitric oxide(NO),and ammonia(NH3)emissions,and N runoff and leaching.However,few comprehensive evalua-tions have been performed on the environmental and economic aspects of biochar amendment or organic sub-stitution.Here,we studied the comprehensive effects of biochar amendment,organic substitution,and biochar amendment combined with organic substitution on crop production,Nr loss,and net ecosystem economic benefit(NEEB)in intensive vegetable production by integrating life-cycle assessment for Nr footprints,empirical models for NH3 volatilization and N runoff and leaching derived from peer-reviewed publications and validated by the current measurements and direct field measurement for N_(2)O and NO emissions during 5 consecutive years of vegetable crop rotations.Five fertilization treatments were applied(SN:synthetic fertilizer application;SNB:SN plus 20 t ha^(−1)biochar amendment;SNM:substituting 50%of chemical N fertilizer with organic manure;SNMB:SNM plus 20 t ha^(−1)biochar amendment;and CK:no fertilizer or biochar addition).Compared with the SN,the SNB increased vegetable yield(28.4%,p<0.05;interannually varying from−10 to 74.9%)and nitrogen use efficiency(29.2%,interannually varying from−39.7 to 150.4%),and decreased field Nr loss(45.4%,p<0.01;interannually varying from−40.3 to 78.4%),and thus improved NEEB by 7.1%;meanwhile,the SNM increased vegetable yield(11.6%,interannually varying from−5.4 to 27.1%)and nitrogen use efficiency(45.7%,p<0.05;interannually varying from 2.3 to 154%),reduced field Nr loss(34.9%,p<0.01;interannually varying from 8.4-39.0%),and thus improved NEEB by 17.8%(p<0.05)compared to the SN,being 56.0×10^(3)Chinese Yuan(CNY)ha^(−1)crop^(−1).Due to the high foreground Nr loss during organic manure production and high input costs of biochar production,the SNMB decreased the NEEB by 8.0%as compared to the SN.Moreover,the SNB and SNM improved vegetable qualities by increasing protein,soluble sugar,and vitamin C contents while decreasing nitrate content(p<0.05).Therefore,single application of biochar amendment or organic substitution would achieve better NEEB and product quality in vegetable production.
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。
