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对作物残余物分解特性的认识是研究农业生态系统中养分循环的重要组成部分。比较了免耕和常规耕作制度下玉米秸秆、小麦秆、大豆叶和茎秆以及降三叶草茎和根残余物联和磷的释放。谷类作物从收获后开始衰老时选择其残余物装入玻璃纤维网袋。大豆叶残余物在收割之前采集。降三叶草残余物在春季单花花开期采集，仅在常规耕作制处理的小区内翻耕入土。总的来说，残余物中碳和磷的变化最好由指数函数或／和对数函数来表述。与残余物放置在土表相比，残余物翻耕入土后碳和磷释放量大而且释放快速。降三叶草茎残余物比其根残余物碳和磷释放快速。大多数残余物磷比碳的初始释放量大。认为碳和磷的释放缺乏相关性是由于初始可变的无机磷含量，这部分磷在分解作用和碳的矿化流失开始之前已准备释放。碳释放的速率和数量差异与植物残余物初始碳和磷含量，或／和相应的木质素含量以及季节影响有关。很明显，土壤耕作是农业生态系统中元素循环的重要调节因子和传动可变因子之一。
Knowledge of the decomposition characteristics of crop residues is an important part of studying nutrient cycling in agro-ecosystems. Compared with no-tillage and conventional tillage systems, the release of corn stalks, wheat stalks, soybean leaves and stalks and the combination of stem and root residues of clover and associated phosphorus were compared. Cereal crops are selected for their residue in fiberglass bags when they begin to age after harvest. Soybean leaf residue is harvested before harvesting. Decreased clover residues were collected in the spring with single flowering and were tilled into the soil only in the plots treated by conventional tillage. In general, changes in carbon and phosphorus in the residue are best characterized by exponential or / and logarithmic functions. Compared with the residue placed on the earth’s surface, the residue after tillage into the soil carbon and phosphorus release large and fast release. Decreasing clover stem residues released carbon and phosphorus faster than their root residues. The majority of the residue phosphorus is larger than the initial amount of carbon released. The lack of correlation between carbon and phosphorus release is thought to be due to the initial variable inorganic phosphorus content, which is already ready for release before decomposition and carbon mineralization losses begin. The rate and amount of carbon release differences are related to the initial carbon and phosphorus content of the plant residues, or / and the corresponding lignin content, as well as the seasonal impact. It is clear that soil tillage is one of the key adjustment and driving variables for elemental cycling in agro-ecosystems.