Karst desertification control of grasslands balances the ecological and economic benefits of ecological restoration and rural ecological animal husbandry development. In the context of global changes and intensified human activities, the fragility of grassland ecosystems under karst desertification control is becoming increasingly evident, and enhancing the ecological resilience and ecosystem services of grasslands is an issue that urgently needs to be addressed. In this paper, the CNKI literature, WOS core databases and Goolgle scholar were used as search sources, identifying 179 articles related to the study of grassland ecosystem vulnerability and ecological resilience. This research systematically reviewed the progress of grassland ecosystem vulnerability research and analyzed the relationship between grassland ecosystem services (GESs) and grassland ecosystem vulnerability and resilience. The direction of enhancing GESs in karst areas is indicated in terms of the reciprocal feedback, synergistic relationship, and mechanism of action of GESs, vulnerability, and resilience. It is also emphasized that the karst desertification area should provide an ecological foundation for the sustainable development of the regional environment around the supply-and-demand relationship of GESs, the trade-off synergy of service flow, and the enhancement of ecological resilience, thereby consolidating the effectiveness of karst desertification control, enhancing GESs, and helping rural revitalization.

To explore the effects of fertilization on physiological and biochemical parameters in the blood of the Wumeng semi-fine wool sheep and select the optimum fertilizer type, we carried out fertilization and grazing experiments on the perennial artificial grassland in Wumeng Prairie. The content of mineral elements in soil, forage and animal tissues was analyzed by atomic emission spectrometry. The blood parameters were analyzed by automatic blood cell analyzer and the blood biochemical parameters were detected by automatic biochemical analyzer. The results showed that fertilization significantly increased nitrogen content (P<0.01), but there was no significant difference between different fertilization treatments. Ammonium sulfate substantially increased the sulfur content of forage (P<0.01) and dramatically decreased the selenium content of forage (P<0.01). At the end of the grazing experiment, the content of copper, iron and selenium in the blood of the Wumeng sheep in the grassland enriched with ammonium sulfate was significantly lower than that in the grassland enriched with ammonium nitrate and the control group (P<0.01), and the sulfur content in the blood of the animals was obviously higher than that in the prairie enriched with ammonium nitrate and the control group (P<0.01). Ammonium sulfate fertilization evidently reduced the hemoglobin and erythrocyte hematocrit capacity of the sheep (P<0.01), while serum ceruloplasmin content, serum superoxide dismutase activity, serum glutathione peroxidase activity and serum catalase activity were significantly lower than that in the prairie enriched with ammonium nitrate and the control group (P<0.01). There were no significant differences in other trace elements, blood parameters and serum biochemical parameters between the fertilization treatment and the control group. Consequently, it is concluded that ammonium sulfate fertilization inhibit the metabolism of trace elements and decline some of the blood physiological and biochemical parameters in the sheep, which has a negative effect on their health, so we have suggested that the use of ammonium sulfate fertilizer should be reduced in pastures with low selenium, iron and copper contents.

The structure and stability of grassland ecosystems have a significant impact on biodiversity, material cycling and productivity for ecosystem services. However, the issue of the structure and stability of grassland ecosystems has not been systematically reviewed. Based on the Web of Science (WOS) and China National Knowledge Infrastructure (CNKI) databases, we used the systematic-review method and screened 133 papers to describe and analyze the frontiers of research into the structure and stability of grassland ecosystems. The research results showed that: (1) The number of articles about the structure and stability of grassland ecosystems is gradually increasing, and the research themes are becoming increasingly diverse. (2) There is a high degree of consistency between the study area and the spatial distribution of grassland. (3) Based on the changes in ecosystem patterns and their interrelationships with ecosystem processes, we reviewed the research progress and landmark results on the structure, stability, structure–stability relationship and their influencing factors of grassland ecosystems; among them, the study of structure is the main research focus (51.12%), followed by the study of the influencing factors of structure and stability (37.57%). (4) Key scientific questions on structural optimization, stability enhancement and harmonizing the relationship between structure and stability are explored. (5) Based on the background of karst desertification control (KDC) and its geographical characteristics, three insights are proposed to optimize the spatial allocation, enhance the stability of grassland for rocky desertification control and coordinate the regulation mechanism of grassland structure and stability. This study provided some references for grassland managers and relevant policy makers to optimize the structure and enhance the stability of grassland ecosystems. It also provided important insights to enhance the service capacity of grassland ecosystems in KDC.

Resource depletion, land-use change, and population growth triggered by the industrial revolution represent serious issues shared globally that have altered the structure, processes, and functions of ecosystems and had significant impacts on human well-being and survival security. This paper assesses changes in ecosystem service values (ESVs) in karst areas based on the perspective of land-use change. Guizhou province, which is typical of the South China Karst (SCK) ecologically fragile areas, was taken as a research subject. The past, current, and future spatial-temporal evolution of karst ESVs were assessed, using equivalence factors and CA-Markov modelling methods. The results show that: (1) from 1980 to 2040, arable land, woodland, and grassland occupy the main land types in the study area; at the same time, the water and built-up areas show a steady growth trend, with dramatic land use shifts occurring in the western, middle, and northern parts. (2) The overall ESVs increased by US$ 31.12 million during the study period, showing a temporal change trend of first decreasing and then increasing; forest land, grassland, and arable land area shift are the main factors of ESVs change; soil conservation, biodiversity conservation, and gas regulation functions are enhanced and play a vital role in the single ESVs increase; ESVs show a basin-type spatial distribution pattern. (3) The sensitivity index is <1, the ESV is inelastic to the VC factor adjustment, and the results are true and valid. This paper found that using quantitative methods to predict land use change of the South China Karst can provide accurate assessment of the differences in supply and demand for natural and social ecosystem services (ES) in a region, clarifying the trade-offs and synergies of ecosystem service functions, contributing to the achievement of sustainable development, and providing a practical reference for global land landscape optimization and land resource planners.

Suitable soil structure and nutrient security are important for plant growth and development. The fractal dimension of soil, along with the distribution of physical and chemical properties and their interactions, plays an important role in studying the stability of soil structures and water and fertilizer cycles. As a sustainable management model, intercropping has positive benefits for erosion control, the spatial optimization of resources, and improving system productivity. The effects of four intercropping methods on the fractal dimension and physicochemical properties of soil were investigated by intercropping Salvia miltiorrhiza with forage and S. miltiorrhiza with forest under typical karst rock desertification habitats in Guizhou. The results showed that the soil nutrient content when intercropping was significantly higher than that of monoculture. The organic carbon content of soil grown under forest is higher than other treatments, and there was a non-significant change in soil water content when intercropping compared with monoculture. The soil fine-grained matter when intercropping was significantly higher than that of monoculture, while the soil fractal dimension showed a tendency to become larger with an increase in fine-grained matter. Intercropping planting, due to its component types and spatial and temporal configurations, leads to differences in soil water and fertilizer interactions, which can be combined with other ecological restoration measures to optimize the composite model and jointly promote the restoration and development of ecologically fragile areas.

The karst area in Southwest China is facing the challenges of environmental degradation and agricultural safety. Intercropping is a green and efficient planting mode that can make full use of the differences in crops’ physiological and ecological characteristics and land and climate resources while considering the environmental and yield benefits. This study selected five treatments: Salvia miltiorrhiza monoculture, Dactylis glomerata intercropped with S. miltiorrhiza, Cichorium intybus intercropped with S.miltiorrhiza, Trifolium repens intercropped with S.miltiorrhiza, and Lolium perenne intercropped with S.miltiorrhiza. Using one-way ANOVA, principle component analysis (PCA), and linear correlation analysis, we analyzed the changes in the soil physicochemical factors and the coupling relationship between them in the intercropping mode. The results showed that at different soil depths, the soil bulk density in the intercropping mode was significantly lower than that in the single cropping mode (p < 0.05), and the soil water content and total porosity were significantly increased (p < 0.05). There were no significant differences in soil pH among the five models (p > 0.05), the content of soil organic matter was significantly higher than that in the single cropping mode (p < 0.05), and the content of nitrogen and phosphorus also showed different changes. The correlation analysis showed that there was no significant correlation between the pH and soil physical properties (p > 0.05); bulk density and chemical properties were negatively correlated, while the soil water content, field water-holding capacity, and total porosity were significantly positively correlated with the chemical properties (p > 0.05). Therefore, it is suggested to strengthen the management of agricultural grass intercropping, improve soil pore structure, regulate the distribution of soil water and fertilizer, and improve the resilience of agricultural systems in the karst area of southwest China.