有机物料腐解过程中养分的释放特征及其影响因素  

Release characteristics and influencing factors of carbon,nitrogen,and phosphorus during decomposition of organic materials

作　　者：梁鑫宇 宋明丹 韩梅[1] 李正鹏 LIANG Xin-yu;SONG Ming-dan;HAN Mei;LI Zheng-peng(Academy of Agriculture and Forestry Sciences,Qinghai University,Xining,Qinghai 810016,China;Xining Observation and Experiment Station of National Agricultural Environment,Xining,Qinghai 810016,China)

机构地区：[1]青海大学农林科学院,青海西宁810016 [2]国家农业环境西宁观测实验站,青海西宁810016

出　　处：《植物营养与肥料学报》2023年第6期1082-1090,共9页Journal of Plant Nutrition and Fertilizers

基　　金：国家自然科学基金项目(32160759);国家绿肥产业技术体系(CARS-22)。

摘　　要：【目的】研究主要作物秸秆养分在土壤中的释放特征,为其合理利用提供科学依据。【方法】在青海农业大学试验站开展有机物料土壤埋袋试验。供试有机物料为马铃薯秆、油菜秆、小麦秆和毛叶苕子,每种物料称取40.0 g于尼龙网袋中,于2021年3月30日埋入20 cm深土壤中自然腐解。埋入土壤后的第7、14、28、42、72、117、162天采样,测定尼龙袋内有机物料干重、碳、氮、磷含量和纤维素、半纤维素、木质素含量,计算物料养分残留率和释放率。【结果】至腐解结束(埋后162天),马铃薯秆、油菜秆、小麦秆和毛叶苕子的碳残留率分别为35.5%、42.2%、53.4%、14.7%。腐解过程中,马铃薯秆、小麦秆和毛叶苕子在埋后0~7天的碳矿化率最大,油菜秆在埋后7~14天的碳矿化率最大。以双库指数积温模型拟合碳残留量随腐解时间的变化,R2均在0.90以上。马铃薯秆、油菜秆、小麦秆、毛叶苕子的年腐殖化系数分别为41%、34%、58%、24%。在整个腐解过程中,小麦秆和毛叶苕子氮素、磷素表现为直接释放,马铃薯秆和油菜秆表现为淋溶—浓缩—释放。腐解至162天,马铃薯秆、油菜秆、小麦秆和毛叶苕子氮素释放率分别为28.0%、10.2%、31.8%、88.3%,磷素释放率分别为45.1%、33.9%、62.4%、71.4%;马铃薯秆、油菜秆和小麦秆磷释放率大于氮释放率,而毛叶苕子的氮释放率大于磷释放率。通过多元逐步回归,有机物料初始碳含量、氮含量、C/P值可以解释氮、磷养分释放的82.5%~98.5%。【结论】有机物料初始碳、氮含量和碳/磷值显著影响着秸秆中氮素和磷素的总释放量。马铃薯秆、油菜秆、小麦秆和毛叶苕子的年腐殖化系数分别达41%、34%、58%、24%。毛叶苕子的氮、磷释放速率快,总释放量高且在腐解过程中持续释放,因而可以替代部分化肥。马铃薯和油菜秆氮、磷释放速率较低,且其释放在腐解过程中表�【Objectives】We studied the nutrient release characteristics of different organic materials in soil to provide a scientific basis for the rational utilization of organic resources.【Methods】The straws of potato(Solanum tuberosum L.),rape(Brassica napus L.),wheat(Triticum aestivum L.)and hairy vetch(Vicia villosa Roth.)were loaded into nylon bags and incorporated in 0-20 cm chestnut soil for natural decomposition in Qinghai University.The nylon bags were sampled at 7,14,28,42,72,117,and 162 days for determining C,N,and P content,residual straw biomass,and the amount and release rate of C,N,and P were calculated.Further,the relationship between material properties and C,N,and P release rate was quantitatively analyzed.【Results】By the end of the decomposition period(162 days),the C residue in the straws of potato,rape,wheat,and hairy vetch were 35.5%,42.2%,53.4%,and 14.7%,respectively.During the decomposition process,potato,wheat,and hairy vetch straw had the fastest C mineralization rate at 0-7 days,while rape straw had the fastest C mineralization rate at 7-14 days.The two-pool exponential accumulated temperature model fitted the C residual process well,with R2>0.90.The annual humification coefficients of potato,rape,wheat,and hairy vetch were 41%,34%,58%,and 24%,respectively.During decomposition,wheat straw and hairy vetch continually released N and P,while the N and P in potato and rape straw exhibited eluviation-concentration-release.At the end of the decomposition period(162 days),the total N released from potato,rape,wheat,and hairy vetch straws were 28.0%,10.2%,31.8%,and 88.3%,and the total P released was 45.1%,33.9%,62.4%,and 71.4%,respectively.The P release rate of potato,rape,and wheat straws was higher than the N release rate,while the N release rate in hairy vetch was higher than the P release rate.Multiple stepwise regression showed that the initial C and N content of the organic materials explained 98.5% of total N release,showing a positive effect,and the C/P ratio explained 82.5% of P rele

关 键 词：有机物料 碳残留率 养分释放 双库指数积温模型 

分 类 号：S141.4[农业科学—肥料学]