Investigation into the Effects of Different Restoration Techniques on the Soil Nutrient Status in Degraded Stipa grandis Grassland

Abstract

The degradation and desertification of grassland ecosystems have garnered significant attention both domestically and internationally. Grassland restoration techniques are widely considered a principal measure to promote the sustainable utilization of grasslands, with soil nutrient content being a core indicator for assessing the effectiveness of restoration in degraded grasslands. This study aims to explore the differential impacts of various grassland restoration methods on soil nutrient distribution in degraded Stipa grandis grasslands. Three major restoration methods, i.e., root cutting, enclosure, and fertilization, were applied in the study area. The soil nutrient content was measured and analyzed under the different restoration methods and at varying depths. The results revealed that under all three restoration methods and at different soil depths (0–10 cm, 10–20 cm, 20–30 cm), the organic matter, total nitrogen, total phosphorus, alkali-hydrolyzable nitrogen, alkali-hydrolyzable phosphorus, and available potassium contents were significantly higher than those in the control group (p < 0.05). Furthermore, as soil depth increased, the contents of organic matter and all nutrients gradually decreased. Specifically, regarding the contents of different nutrients, the order of organic matter, total nitrogen, total phosphorus, alkali-hydrolyzable nitrogen, and available phosphorus was as follows: fertilization > enclosure > root cutting > control, while the contents of total potassium and available potassium followed the sequence: fertilization > enclosure > control > root cutting. Additionally, based on the canonical correlation analysis (R2 = 0.88), the total phosphorus content in soil had the greatest impact on soil nutrients, while vegetation cover and plant height contributed the most to vegetation characteristics. In grassland restoration, the increase in soil total phosphorus led to higher vegetation cover and height, mildly influenced plant diversity and density, and simultaneously promoted biomass accumulation. These research findings provide a solid theoretical foundation for the application of grassland restoration techniques, contributing to the sustainable development of grassland ecosystems.

Effects of Different Ecological Restoration Pattern on Soil Organic Nitrogen Components in Alpine Sandy Land

“…However, this is different from the distribution characteristics of soil nitrogen in the different soil layers under different ecological restoration patterns in the arid and semi-arid areas of Northern China. Wang et al [16] and Zhang et al [44] studied the soil nitrogen content under different ecological restoration patterns in North China, and found that the soil nitrogen content decreased with the deepening of the soil layer. The reason for this may be that the ecological restoration in North China is more susceptible to temperature and humidity, which determine the growth and metabolism of soil microorganisms.…”

Effects of Organic Fertilizer Addition to Vegetation and Soil Bacterial Communities in Saline–Alkali-Degraded Grassland with Photovoltaic Panels

“…Grassland ecosystems are an important basis for animal husbandry and have various functions, such as supporting biodiversity, regulating climate, preventing soil erosion, and maintaining ecosystem balance [ 2 , 3 ]. In China, grasslands face serious challenges, including degradation, soil erosion, and declining productivity, due to natural factors and unsustainable land use patterns [ 4 ]. Soil salinization is the main cause of land degradation, which has serious consequences for global agricultural production and the ecological environment [ 5 ].…”