秸秆深度粉碎均匀抛洒还田降低秸秆焚烧率并提高养分归还量  

Deep smashing and uniform incorporation of straw prevent straw burning and improve the return of nutrients to soil

作　　者：李超[1] 程凯凯[1] 廖育林[1] 郭立君[1] 周峻宇 罗先富 文丽 唐海明[1] 汤文光[1] 汪柯[1] 肖小平[1] LI Chao;CHENG Kai-kai;LIAO Yu-lin;GUO Li-jun;ZHOU Jun-yu;LUO Xian-fu;WEN Li;TANG Hai-ming;TANG Wen-guang;WANG Ke;XIAO Xiao-ping(Institute of Soil Fertility Research in Hunan Province,Changsha,Hunan 410125,China;Hunan Rice Research Institute,Changsha,Hunan 410125,China)

机构地区：[1]湖南省土壤肥料研究所,湖南长沙410125 [2]湖南省水稻研究所,湖南长沙410125

出　　处：《植物营养与肥料学报》2021年第7期1141-1150,共10页Journal of Plant Nutrition and Fertilizers

基　　金：国家重点研发计划项目(2016YFD0300906);湖南省自然科学基金项目(2020JJ5320)。

摘　　要：【目的】研究粉碎程度与还田方式对减少秸秆焚烧率及其养分损失的影响,以提升秸秆还田的科学性和可行性。【方法】水稻秸秆还田田间试验与模拟试验在湖南宁乡进行。田间试验设秸秆传统不粉碎条带还田(T1)、中度粉碎条带还田(T2)、深度粉碎均匀抛撒还田(T3)3个处理,T1、T2、T3的秸秆还田长度分别为39.0、14.4、5.3 cm,抛撒均匀度分别为37.7%、45.4%、87.4%。模拟试验设置与田间试验T1、T2、T3处理相对应的M1、M2、M3处理,并增加秸秆深度粉碎条带还田(M4)处理。早稻收获后,秸秆按照处理进行焚烧后还田,分析秸秆焚烧率,测定焚烧前及焚烧后还田秸秆灰渣的养分含量,计算养分损失量及损失率。在焚烧后第1天及在晚稻成熟期,测定土壤的氮、磷、钾和有机质含量。【结果】模拟试验条带还田下,秸秆粉碎程度为M4时,焚烧率显著低于M1和M2,焚烧后M4处理的灰渣中氮含量分别较M1、M2处理显著增加76.5%、73.5%,磷含量分别减少42.0%、39.1%,钾含量分别减少11.1%、10.7%,碳含量分别显著增加37.3%、36.0%。田间试验秸秆(不含稻茬)焚烧后,T2处理秸秆中的C、N、P_(2)O_(5)、K_(2)O平均损失量分别为1101.3、34.1、2.7、13.9 kg/hm^(2),平均损失率分别为91.1%、89.8%、22.4%、16.1%。T3处理秸秆无法焚烧,从而实现了养分理论上全量归还。与焚烧前相比,T1和T2处理平均N、P_(2)O_(5)、K_(2)O的养分归化比分别下降了18.8、3.2、8.2个百分点;与T1和T2处理的平均值相比,T3处理的N、P_(2)O_(5)、K_(2)O的养分归化比分别增加了18.7、3.5、9.1个百分点。经过秸秆焚烧后,T3处理土壤的速效氮、磷、钾含量在晚稻成熟期显著高于T1和T2处理,活性有机质含量3个处理间没有显著差异。【结论】秸秆深度粉碎结合均匀抛撒还田可基本防止秸秆焚烧,实现秸秆养分全量归还,降低秸秆焚烧所造成的养分损失,促进双季稻田土壤周�【Objectives】To increase the practicality of returning straw to soil,the effects of smashing degree and returning method on reducing the straw burning rate and nutrient loss were explored.【Methods】Field and simulated experiments of returning rice straw to soil were carried out in Ningxiang,Hunan.The treatments included returning straw to the field in the belt without smashing(T1),returning moderately smashed straw to the field in the belt(T2),and returning deeply smashed straw to the field evenly(T3).The length of the straw returned in T1,T2,and T3 were 39.0 cm,14.4 cm,and 5.3 cm,respectively.The corresponding uniformity coefficient was 37.7%,45.4%,and 87.4%,respectively.The treatments in the simulated experiment had the same straw length and returning patterns as T1,T2,and T3 in the field experiment,but recorded as M1,M2,and M3,respectively,and an extra treatment of returning deeply smashed straw(5.3 cm)to the field in the belt(M4).After harvesting early rice,the straw was burned and returned to the field according to the designated treatments.The burning rate of straw and the nutrient content of straw ash were analyzed to calculate nutrient loss and loss rate.The contents of N,P,K,and organic matter in the soil were determined one day after burning and at the maturity of late rice.【Results】Under simulated experiment,when the degree of straw smashing reached M4 in the belt,the burning rate was significantly lower than those in M1 and M2,the N content of M4 treatment in the ash after burning(P<0.05)increased by 76.5%and 73.5% compared with those of M1 and M2 treatments,respectively.Phosphorus content(P<0.05)decreased by 42.0% and 39.1%;potassium content decreased by 11.1% and 10.7%;and carbon content increased by 37.3% and 36.0%.After burning the straw(excluding rice stubble)on the experimental field,the average losses of C,N,P_(2)O_(5) and K_(2)O in T2 were 1101.3,34.1,2.7,and 13.9 kg/hm^(2);the average loss rates were 91.1%,89.8%,22.4%,and 16.1%,respectively.T3 straws could not be burnt;thus,all the

关 键 词：秸秆粉碎 秸秆还田方式 秸秆焚烧 秸秆养分 土壤养分 

分 类 号：S141.4[农业科学—肥料学]