长期施肥对黑土呼吸过程的影响

土壤呼吸是土壤有机C矿化分解,释放无机养分的重要生物化学过程。对公主岭地区长期有机肥(不施有机肥、施中量和高量有机肥处理)与化肥(不施化肥、施用N、NP、NPK化肥)配合施用的12个处理的黑土进行室内好气培养(196天),采用一级动力学方程模拟土壤的呼吸过程,结果表明,有机肥和化肥的施用能显著增加土壤呼吸释放的CO2 -C的累积量,提高土壤中潜在矿化的有机碳含量及其占土壤有机质的比例,促进土壤有机质中无机养分的释放,有利于提高土壤养分的有效性,改善黑土的供肥状况。有机肥与NPK化肥配合施用效果更为明显。

Effect of Long-term Fertilization on Respiration Process of Mollisols

Soil respiration is one of the most important biochemical processes that are relevant to the decomposition of soil organic carbon and release of soil mineral nutrients. In this paper, we carried out an experiment of aerobic incubation using the Mollisols collected from the long-term fertilization site starting from 1981 in Gonzhuling, Jilin Province. The treatments include different levels and combination of organic manure and mineral fertilizers. After incubation, we simulated the curve of the CO_2 released through the soil respiration with incubation time according to the first order kinetic equation. The results indicated that the application of both organic manure and mineral fertilizers to soils could significantly increase the cumulative CO_2-C released through soil respiration, the potentially mineralized C content, and the ratio to total soil organic carbon and the mineralization rate constant. Long-term fertilization favored the release of mineral nutrients from the soil organic matter, thus increased the availability of soil mineral nutrients to crops and improved soil fertility status of the Mollisols. The interactive effect of organic manure and mineral NPK on soil respiration process was more significantly than that of other treatments.