[Distribution Characteristics of Soil Aggregate Stability and Organic Carbon of Different Grassland Types in the Temperate Desert of Longzhong Loess Plateau].
Huan Jing Ke Xue
; 45(9): 5431-5440, 2024 Sep 08.
Article
em Zh
| MEDLINE
| ID: mdl-39323160
ABSTRACT
Soil aggregate stability and organic carbon ï¼SOCï¼ are important indicators of soil structure and quality and play a key role in the improvement of soil quality in temperate deserts. This study aimed to investigate the distribution patterns, stability of soil aggregates, and variation characteristics of the content of aggregate organic carbon in different grassland types in temperate deserts and their interrelationships. Four grassland types in a temperate desert ï¼Kalidium foliatum type, Reaumuria songarica type, Salsola passerina type, and Sympegma regelii typeï¼ in the Longzhong Loess Plateau as research objects, and the soil aggregate particle size distribution characteristics were determined using the wet sieving method. The stability of soil aggregates was analyzed by calculating aggregate stability indicators and the contribution of aggregate particle size SOC to bulk soil SOC content. Correlation analysis, principal component analysis, and linear fitting equations were used to reveal the relationship between the soil aggregate content and aggregate particle size SOC and aggregate stability. The results showed that the content of >0.25 mm aggregates ï¼R0.25ï¼, mean weight diameter ï¼MWDï¼, geometric mean diameter ï¼GMDï¼, and bulk soil SOC content in each soil layer ï¼0-10, 10-20, and 20-30 cmï¼ of the K. foliatum type grassland were significantly higher than that of the R. songarica type and S. regelii type ï¼P<0.05ï¼. The SOC content of 0.053-0.25 mm and <0.053 mm particle size in each soil layer of the K. foliatum type grassland were significantly higher than that of the S. regelii type ï¼P<0.05ï¼. Surface and subsurface soils ï¼0-10 cm and 10-20 cmï¼ had the significantly highest contribution of 0.25-2 mm particle size SOC to the bulk soil SOC content ï¼P<0.05ï¼. Additionally, as the soil layer deepened, the R0.25, MWD, GMD, bulk soil, and aggregate SOC contents of the K. foliatum type grassland showed a tendency to increase first and then decrease, with the highest contents from 10-20 cm. Kalidium foliatum type grassland aggregate content was dominated by 0.25-2 mm aggregates, whereas the other three grassland types were dominated by 0.053-0.25 mm aggregates. In addition, bulk soil SOC content was significantly correlated with R0.25, MWD, GMD, and ELT ï¼P<0.01ï¼, and the 0.25 mm aggregate was the critical size of positive and negative correlation. R0.25, MWD, GMD, and ELT values were the key factors influencing bulk soil SOC in grassland. The equation fitted to bulk soil SOC content, and GMD was the most suitable to describe the relationship between SOC content and the stability of soil aggregates. Therefore, compared with other grassland types, K. foliatum type grassland had a promoting effect on the soil aggregate stability and the improvement of soil quality.
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Base de dados:
MEDLINE
Idioma:
Zh
Ano de publicação:
2024
Tipo de documento:
Article