Abstract Monitoring long-term grazing management practices influence on soil quality (SQ) is essential to ensuring pasture sustainability, which is the largest land use in world agroecosystems. The aim of this study was to quantify SQ based on long-term (15-years) conservation pasture management and landscape position using the Soil Management Assessment Framework (SMAF). Treatments were setup in 15 watersheds (0.14 ha each, 8% slope) in a completely randomized design with five pasture management practices: continuously grazed (CG), hayed (H), rotationally grazed (R), rotationally grazed with an unfertilized buffer strip (RB), and rotationally grazed with an un-grazed, unfertilized, and fenced riparian strip (RBR). Each watershed was divided in three zones (A, B, and C), with the riparian buffer strip (RBS) corresponding to the RBR D zone. Selected soil chemical, physical, and biological properties were determined on soil samples collected in 2017 (0−15 cm depth) per zone. Total P, organic C, and total suspended solids (TSS) were measured in 2017 runoff samples. The SMAF SQ scores were evaluated individually and as an overall SQ index (SQI). Exponential models were used to investigate the relationship between SQI and total P, organic C runoff, and TSS loads. Continuously grazed watersheds had improved soil fertility, with greater nutrient concentration at the shoulder landscape position (zone A). Degradation of soil physical properties were not observed for this practice. After 15 years of continuous management, CG and R watersheds had the greatest SQI (7.07 and7.05, respectively), not differing from RBR (6.93), likely owing to cattle manure deposition for these treatments. Increased SQI in RBS (7.33) improved SQI for RBR watersheds. Differences in SQI were mostly driven by changes in pH, electrical conductivity, soil P and K concentrations. The exponential models indicated that 34 and 28 % of the variation in P and TOC runoff loads, respectively, can be explained by the SMAF SQI (p

中文翻译：

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遵循长期保护性牧场管理实践的土壤质量指数

摘要 监测长期放牧管理实践对土壤质量 (SQ) 的影响对于确保牧场可持续性至关重要，牧场是世界农业生态系统中最大的土地利用。本研究的目的是使用土壤管理评估框架 (SMAF) 量化基于长期（15 年）保护牧场管理和景观位置的 SQ。在 15 个流域（每个流域 0.14 公顷，坡度 8%）中进行了处理，采用了五种牧场管理实践的完全随机设计：连续放牧 (CG)、干草 (H)、轮作放牧 (R)、用未施肥的缓冲带轮作放牧(RB)，并用未放牧、未施肥和围栏的河岸带 (RBR) 轮流放牧。每个流域分为三个区（A、B 和 C），河岸缓冲带 (RBS) 对应于 RBR D 区。选定的土壤化学、物理和生物特性是根据 2017 年（0-15 厘米深度）每个区域收集的土壤样本确定的。在 2017 年径流样本中测量了总磷、有机碳和总悬浮固体 (TSS)。SMAF SQ 分数被单独评估并作为整体 SQ 指数 (SQI) 进行评估。指数模型用于研究 SQI 与总磷、有机碳径流和 TSS 负荷之间的关系。持续放牧的流域提高了土壤肥力，肩部景观位置（A 区）的养分浓度更高。这种做法没有观察到土壤物理性质的退化。经过 15 年的连续管理，CG 和 R 流域的 SQI 最高（分别为 7.07 和 7.05），与 RBR（6.93）没有区别，这可能是由于这些处理的牛粪沉积所致。RBS 中 SQI 的增加 (7.33) 改善了 RBR 流域的 SQI。SQI 的差异主要是由 pH、电导率、土壤 P 和 K 浓度的变化驱动的。指数模型表明 P 和 TOC 径流负荷的变化分别有 34% 和 28% 可以通过 SMAF SQI (p