Chang Chien S W, Wang M C, Hsu J H, Seshaiah K
Department of Environmental Engineering and Management, Chaoyang University of Technology, Wufong Township, Taichung County 41349, Taiwan, Republic of China.
J Agric Food Chem. 2006 Sep 6;54(18):6790-9. doi: 10.1021/jf061275m.
The qualitative and quantitative characteristics of soil organic carbon (SOC) and related humic acids (HAs) extracted from the soils of field plots were investigated after 8 years of annual paddy (Oryza sativa L.) and upland maize (Zea mays L.) rotation with various fertilizations. Seven fertilization treatments were selected: Ck (no inputs); Chem (chemical fertilizer of NPK); Comp (swine compost); Comp + 33% of Chem N rate; Comp + 67% of Chem N rate; GM (legume green manure) + 33% of Chem N rate; and peat + 33% of Chem N rate. Organic and inorganic nitrogen inputs of six treatments were equivalent with respect of nitrogen content, but Comp, GM, and peat treatments were complemented with various amounts of inorganic N. After harvest of the eighth paddy crop, surface soil samples collected from the plots were subjected to soil characterizations and extraction of humic substances, which were used for chemical, spectroscopic (FTIR, 13C NMR, ESR, X-ray diffractometry), delta13C, and 14C dating analyses. The yields of HAs extracted from the seven treatments were significantly different. Treatment containing persistent organic compound such as the peat + 33% N treatment increased the humification process in topsoils and produced higher yield of HA. Spectroscopic analyses revealed that fertilization treatments changed the functional groups, alkyl C, crystalline characteristics, and delta13C ratios of HAs and turnover rate of SOC considerably. The SOC of the peat + 33% N treatment had the highest mean residence time of 3100 years. Various fertilizer treatments are correlated with turnover rate of SOC and related HAs, which are associated with concerned carbon sequestration as well as mitigation of CO2 emission in the soil environment.
在对稻田（水稻）和旱地玉米进行8年不同施肥方式的轮作后，对田间小区土壤中提取的土壤有机碳（SOC）和相关腐殖酸（HAs）的定性和定量特征进行了研究。选择了七种施肥处理：Ck（不施肥）；Chem（氮磷钾化肥）；Comp（猪粪堆肥）；Comp + 33%化学氮肥用量；Comp + 67%化学氮肥用量；GM（豆科绿肥）+ 33%化学氮肥用量；泥炭 + 33%化学氮肥用量。六种处理的有机和无机氮输入在氮含量方面相当，但Comp、GM和泥炭处理补充了不同数量的无机氮。在第八季水稻收获后，从小区采集表层土壤样本进行土壤特性分析和腐殖物质提取，用于化学、光谱（傅里叶变换红外光谱、13C核磁共振、电子自旋共振、X射线衍射）、δ13C和14C年代测定分析。从七种处理中提取的腐殖酸产量有显著差异。含有持久性有机化合物的处理，如泥炭 + 33%氮处理，增加了表层土壤的腐殖化过程，并产生了更高的腐殖酸产量。光谱分析表明，施肥处理显著改变了腐殖酸的官能团、烷基碳、晶体特性、δ13C比值以及土壤有机碳的周转速率。泥炭 + 33%氮处理的土壤有机碳平均停留时间最长，为3100年。不同的施肥处理与土壤有机碳及其相关腐殖酸的周转速率相关，这与土壤环境中相关的碳固存以及二氧化碳排放的缓解有关。
