Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China.
Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China.
Sci Total Environ. 2018 Mar;616-617:564-571. doi: 10.1016/j.scitotenv.2017.10.301. Epub 2017 Nov 16.
Understanding the influences of land use conversions on soil quality (SQ) and function are essential to adopt proper agricultural management practices for a specific region. The primary objective of this study was to develop soil quality indices (SQIs) to assess the short-term influences of different land uses on SQ in semiarid alkaline grassland in northeastern China. Land use treatments were corn cropland (Corn), alfalfa perennial forage (Alfalfa), monoculture Lyemus chinensis grassland (MG) and successional regrowth grassland (SRG), which were applied for five years. Twenty-two soil indicators were determined at 0-20cm depth as the potential SQ indicators. Of these, thirteen indicators exhibited treatment differences and were identified as the total data set (TDS) for subsequent analysis. Principal component analysis was used with the TDS to select the minimum data set (MDS), and four SQIs were calculated using linear/non-linear scoring functions and additive/weighted additive methods. Invertase, N:P ratio, water-extractable organic carbon and labile carbon were identified as the MDS. The four SQIs performed well, with significant positive correlations (P<0.001, n=16) among them. However, the SQI calculated using the non-linear weighted additive integration (SQI-NLWA) had the best discrimination under different land-use treatments due to the higher F values and larger coefficient of variance as compared to the other SQIs. The SQI value under the MG treatment was the highest, followed by that under the SRG and Alfalfa treatments, and all of these were significantly higher than that of Corn treatment. These results indicated that conversion of cropland to perennial forage or grassland can significantly improve the SQ in the Songnen grassland. In addition, SQI-NLWA can provide a better practical, quantitative tool for assessing SQ and is recommended for soil quality evaluation under different land uses in semiarid agroecosystems.
了解土地利用变化对土壤质量（SQ）和功能的影响对于采用特定地区的适当农业管理实践至关重要。本研究的主要目的是开发土壤质量指数（SQI），以评估不同土地利用对中国东北半干旱碱性草原短期土壤质量的影响。土地利用处理为玉米耕地（玉米）、多年生苜蓿牧草（苜蓿）、单种芨芨草草地（MG）和演替再生草地（SRG），应用于五年。在 0-20cm 深度测定了 22 个土壤指标作为潜在土壤质量指标。其中，13 个指标表现出处理差异，被确定为后续分析的总数据集（TDS）。采用主成分分析法对 TDS 进行分析，选择最小数据集（MDS），并采用线性/非线性评分函数和加性/加权加性方法计算四个 SQI。转化酶、N:P 比、水可提取有机碳和活性碳被确定为 MDS。四个 SQI 表现良好，它们之间存在显著的正相关（P<0.001，n=16）。然而，与其他 SQI 相比，基于非线性加权加性综合（SQI-NLWA）的 SQI 在不同土地利用处理下具有更好的区分能力，因为它具有更高的 F 值和更大的变异系数。MG 处理下的 SQI 值最高，其次是 SRG 和苜蓿处理下的 SQI 值，均显著高于玉米处理下的 SQI 值。这些结果表明，将耕地转化为多年生牧草或草地可以显著提高松嫩草原的土壤质量。此外，SQI-NLWA 可以为评估土壤质量提供更好的实用定量工具，建议在半干旱农业生态系统中不同土地利用下进行土壤质量评价。
