USDA-ARS, Grassland, Soil and Water Research Laboratory, 808 E. Blackland Rd., Temple, TX, 76502, USA.
J Environ Qual. 2023 May-Jun;52(3):434-447. doi: 10.1002/jeq2.20315. Epub 2022 Jan 6.
Understanding indicators of soil health is crucial for developing agricultural systems that are sustainable and climate resilient. Labile soil carbon (C), microbial properties, and nutrient status are all incorporated into the Haney Soil Health Tool with the goal of summarizing several indicators into one index. Monthly soil samples from an integrated crop-livestock system in Central Texas were collected from 2017 to 2019. Fields represented a range of management practices, including cover crops, no-till, rotational grazing, and a native prairie remnant. Soil samples were analyzed for total C, water-soluble C, macro- and micronutrient content and bioavailability, and phospholipid fatty acids (PLFAs). Microbial activity was determined via a 24-h CO incubation. Soil health score, C, and PLFAs were well correlated with each other. The greatest total PLFA (219.5 nmol g soil) and organic C (54.3 g kg soil) were found in the native prairie, and the lowest were found in the unfertilized continuous-corn system (60.5 nmol PLFAs g soil and 24.0 g organic C kg soil). Of all agroecosystems, the perennial grazing system (soil health score, 24.7) was most similar to the native prairie (soil health score, 27.4), having high soil C and a large microbial community. Of the row cropping systems, the no-till system approached the perennial systems better than the conventional till and unfertilized conventional till (soil health score, 11.1 vs. 8.0 and 5.3, respectively). This study highlights the value of perennial grass grazing in agroecosystems and appropriate best management practices. Expanding this analysis to other sites may provide additional insight.
了解土壤健康指标对于开发可持续和具有气候适应力的农业系统至关重要。易变土壤碳 (C)、微生物特性和养分状况都被纳入 Haney 土壤健康工具中，旨在将多个指标汇总为一个指数。2017 年至 2019 年，从德克萨斯州中部的一个综合作物-牲畜系统中每月采集土壤样本。这些田地代表了一系列管理实践，包括覆盖作物、免耕、轮牧和原生草原残余物。土壤样本用于分析总 C、水溶性 C、宏量和微量元素含量及生物有效性和磷脂脂肪酸 (PLFA)。通过 24 小时 CO 孵育测定微生物活性。土壤健康评分、C 和 PLFA 彼此高度相关。原生草原的总 PLFA（219.5 nmol g 土壤）和有机 C（54.3 g kg 土壤）最高，而未施肥的连续玉米系统中含量最低（60.5 nmol PLFA g 土壤和 24.0 g 有机 C kg 土壤）。在所有农业生态系统中，多年生放牧系统（土壤健康评分 24.7）与原生草原（土壤健康评分 27.4）最为相似，具有较高的土壤 C 和较大的微生物群落。在带状作物系统中，免耕系统比传统耕作和未施肥的传统耕作更接近多年生系统（土壤健康评分分别为 11.1、8.0 和 5.3）。本研究强调了多年生草放牧在农业生态系统中的价值和适当的最佳管理实践。将这种分析扩展到其他地点可能会提供更多的见解。
