ABSTRACT

Manure application can enhance soil fertility and crop yield; however, knowledge of optimum application rates of manure is needed to prevent negative impacts on soils and environment. This study was aimed to compare the long-term effects of manure and inorganic fertilizer application at different rates on soil nutrients, aggregate stability, organic carbon, and nitrogen in different aggregate size fractions. The experiment was conducted on a long-term manure site under a randomized complete block design with six treatments: three manure [low manure (LM; application based on phosphorous requirement), medium manure (MM; application based on nitrogen requirement), high manure (HM; two times prescribed nitrogen rate)], two chemical fertilizer [medium fertilizer (MF; suggested inorganic fertilizer rate), high rate of fertilizer (HF)], and control (CK; no manure nor fertilizer). Manure application maintained soil pH, improved nutrient availability and aggregate stability compared to the CK. The HM treatment increased aggregate-associated soil organic carbon (SOC) and total nitrogen (TN) concentration by 40 to 50% in all size fractions as compared to the CK. Further, HM increased particulate organic matter (POM) by 1.2 times as compared to the CK, while inorganic fertilizer application did not alter these parameters compared to the CK.

摘要

施肥可提高土壤肥力和作物产量；然而，需要了解肥料的最佳施用率，以防止对土壤和环境造成负面影响。本研究旨在比较不同施用量的粪肥和无机肥料对不同团聚体大小部分的土壤养分、团聚体稳定性、有机碳和氮的长期影响。该试验在一个长期施肥场地进行，采用随机完整区组设计，共六种处理：三肥[低肥（LM；根据磷需求施用）、中肥（MM；根据氮需求施用）、高肥（HM；两倍规定的施氮量）]、两种化肥[中肥（MF；建议无机肥用量）、高施肥量（HF）]、对照（CK；没有肥料也没有肥料）。与 CK 相比，施肥可保持土壤 pH 值、改善养分有效性和团聚体稳定性。与 CK 相比，HM 处理在所有尺寸部分中增加了 40% 至 50% 的聚集体相关土壤有机碳 (SOC) 和总氮 (TN) 浓度。此外，与 CK 相比，HM 使颗粒有机物 (POM) 增加了 1.2 倍，而与 CK 相比，无机肥料的施用并未改变这些参数。