College of Natural Resources and Environment, Northwest A&F University, Key Laboratory of Plant Nutrition and Agro-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, Shaanxi, China.
College of Natural Resources and Environment, Northwest A&F University, Key Laboratory of Plant Nutrition and Agro-environment in Northwest China, Ministry of Agriculture, Yangling, 712100, Shaanxi, China; Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
Sci Total Environ. 2022 Jan 1;802:149657. doi: 10.1016/j.scitotenv.2021.149657. Epub 2021 Aug 14.
The decomposition of organic matter mediated by soil enzymes is the key process that transports carbon from the soil into the atmosphere. To better understand the effect of global warming on organic matter decomposition, we evaluated the temperature sensitivity (Q) of invertase (EC3.2.1.26), β-glucosidase (EC3.2.1.21), urease (EC3.1.1.5), acid phosphatase (EC3.1.3.2), and arylsulfatase (EC3.1.6.1) activities in red soil from the subtropical region and black soil from the mid-temperate region at 5, 15, 25, 35, and 45 °C. Further, the in-situ stoichiometry of the products released by enzymes was modelled. All of the enzyme activities in the tested soils increased with the increasing temperature (1.1-8.9 fold per 10 °C), indicating an enhanced degradation of the organic substrate with warming. In the lower temperature range (5-25 °C), Q of the enzyme activities in the red soil evaluated in terms of total enzyme activity index were more prominent than that in black soil (1.53 and 3.46 vs 1.16 and 3.19). Changes in the in-situ stoichiometry of enzyme products with warming indicated that, in colder months (Jan. to Apr. and Oct. to Dec.), the microbial nutrient demand in the red soil exhibited the following order, N > P > S > C. While in the black soil, it suggested that there is increasing microbial demand for only N and S. In the warmer months (May to Sep.), the microbial nutrient demands in the two soils were opposite to the colder months. The results suggested differential changes in microbial nutrient limitation with warming, which has significant implications for the carbon stocks management in farmlands under the changing global climate.
土壤酶介导的有机物分解是将碳从土壤输送到大气中的关键过程。为了更好地理解全球变暖对有机物分解的影响，我们评估了亚热带红壤和中温带黑土中蔗糖酶（EC3.2.1.26）、β-葡萄糖苷酶（EC3.2.1.21）、脲酶（EC3.1.1.5）、酸性磷酸酶（EC3.1.3.2）和芳基硫酸酯酶（EC3.1.6.1）在 5、15、25、35 和 45°C 下的温度敏感性（Q）。此外，还对酶释放产物的原位化学计量进行了模拟。在所测试的土壤中，所有酶活性都随温度升高而增加（每升高 10°C 增加 1.1-8.9 倍），这表明随着变暖，有机底物的降解增强。在较低的温度范围内（5-25°C），红土中以总酶活指数评估的酶活性的 Q 值大于黑土（1.53 和 3.46 比 1.16 和 3.19）。随着变暖，酶产物原位化学计量的变化表明，在较冷的月份（1 月至 4 月和 10 月至 12 月），红土中微生物的养分需求按以下顺序排列：N > P > S > C。而在黑土中，微生物对 N 和 S 的需求逐渐增加。在较暖的月份（5 月至 9 月），两种土壤中微生物的养分需求与较冷的月份相反。结果表明，随着变暖，微生物养分限制发生了不同的变化，这对气候变化下农田的碳储量管理具有重要意义。
