江西省水稻秸秆养分资源量及其还田效果研究OA

Jiangxi Province is an important double-season rice producing area in China,and clarifying the regional distribu-tion characteristics of its straw resources and the nutrient substitution potential of straw returning can provide a theoretical basis for promoting the comprehensive and efficient use of straw in the province and the reduction and efficiency of fertilizer on farmland.This paper is based on the amount of rice straw generated in each county of Jiangxi Province in 2023,com-bined with the nitrogen,phosphorus and potassium nutrient content in straw and its nutrient release rate in the season under the condition of field return to project the amount of fertilizer substitutable for rice straw returning to the field,and through the monitoring data of the effect of straw returning to the field in key counties of Jiangxi Province for comprehensive utiliza-tion of straw,to reveal the characteristics of the resources of rice straw and potential for alternative use of fertilizers in Jian-gxi Province.The results showed that the total annual output of rice straw in Jiangxi Province in 2023 was 2126.50 × 104 t,of which 59.29％ was in Northern Jiangxi Province,30.10％ was in Central Jiangxi Province,and 10.61％ was in Southern Jiangxi Province.And the main source of rice straw resources in Jiangxi province is the double-season rice growing area,with early and late rice straw resources accounting for more than 70％.The total nutrient resources of rice straw in Jiangxi Province were 18.42 × 104 t(N),6.34 ×104t(P2O5)and41.78 × 104 t(K2O),and the seasonal nutrient res-titution of rice straw was 10.27 × 104 t(N),3.68 × 104 t(P2O5)and 37.68 × 104 t(K2O),with the total amount of 51.63 × 104 t.53.81％ of the nutrient restitution was concentrated in Northern Jiangxi Province.The straw returning treat-ments all had the tendency to promote the cohesion and cementation of soil particles,i.e.,from microagglomerates(＜53μm)to medium-large agglomerates(＞250 μm).The soil available nitrogen,available potassium and organic matter con-tents were all enhanced by the straw returning treatment,especially the full-amount straw returning treatment,which had a more significant effect on the soil available potassium and organic matter contents.The half-amount straw returning had a certain enhancement effect on the yield of late rice,while the full-amount straw returning had no significant effect on the yield.There are some variations in the total amount of rice straw resources in different regions of Jiangxi Province,and the overall performance is"more in the north and less in the south",which should be adapted to local conditions to strengthen the efficient utilization of straw;under the scenario of straw returning,it is necessary to consider the substitution of fertiliz-ers for returned straw to promote the reduction of fertilizers,efficiency and green development of agriculture.