Dual impacts of long-term vegetation management practices on plant-soil ecological multifunctionality: Call for sustainable management in desert ecosystems

Abstract

Human-driven vegetation management practices (VMPs) employed in agricultural activities and livelihoods pose potential threats to native plant communities. However, there remains a significant gap in comprehensive understanding regarding the long-term effects of VMPs on the ecological multifunctionality of plant-soil systems within desert ecosystems. Therefore, it is essential to conduct thorough studies and analyses examining the implications of these practices on plant-soil interactions to enable informed decision-making regarding the effective management of desert ecosystems. The Taklamakan Desert in China, which is recognized as one of the largest and driest deserts globally, serves as a valuable model for investigating the impact of human activities on desert environments. This study assessed the long-term (16 years) effects of four distinct VMPs—control (no disturbance), burning, spring cutting, and autumn cutting, as well as irrigation—on Alhagi sparsifolia and its associated soil layers (0–50 cm and 50–100 cm) under realistic field conditions. The irrigation treatment increased aboveground biomass, reduced electrical conductivity and sodium concentration, and decreased soil organic carbon pools across both soil layers. Conversely, spring and autumn cutting led to diminished plant biomass and nutritional value. While autumn cutting increased soil cation levels and effectively lowered salinity compared to control plots, spring cutting did not yield significant effects on these functions. Burning, on the other hand, significantly reduced plant biomass and increased soil salinity but unexpectedly enhanced certain soil functions, likely attributable to the low intensity of the fire and the sparse plant coverage typical of desert ecosystems. All VMPs exhibited dual effects, promoting specific ecological functions while compromising others. The harvesting of vegetation, particularly during the spring, along with burning practices, may considerably disrupt the fragile equilibrium of the plant-soil system and associated ecosystem services. However, a comprehensive assessment to evaluate the overall balance of benefits and drawbacks of VMPs is crucial. To foster the sustainable management and utilization of desert plant communities to combat desertification, it is imperative to implement key actions, including providing alternative fuel sources, assessment of annual biomass consumption, and capacity-building initiatives for farmers.