Abstract:
Objective Identifying the tradeoffs and synergies between soil water conservation and soil nutrient accumulation is one of the key issues in exploring influence of human activities on soil ecosystem services.
Method Based on field sampling and experimental analysis, multivariate statistical methods were used to study the responses of soil moisture and nutrients to different re-vegetation types in a typical loess watershed.
Result (1) All introduced vegetation restorations would decrease soil water content, especially the deep soil layers in forests and shrubs. Generally, re-vegetation could increase soil nutrients. (2) The accumulation of soil organic matter (SOC), total nitrogen (N) and available potassium (K) in forestland and shrubland were significantly higher than those in grassland. However, the accumulation of available phosphorus (P) was relatively lower than other soil nutrients and has no significant difference between different vegetation types. In addition, all introduced vegetation could cause decreasing of total P and available N. The accumulations of SOC and total N significantly increased with the years of vegetation growth. (3) The significant correlations between soil moisture deficit and high soil nutrient accumulation were found in forests and shrubs and showed relatively high tradeoff between these two soil ecosystem services. The tradeoff and synergy between soil moisture content and soil nutrient content in grasslands suggested relatively sustainability of soil ecosystem services than other vegetation types.
Conclusion Considering the tradeoff and synergy between soil moisture and soil nutrient in different vegetation restoration types in semi-arid Loess Plateau, scientific guidance and reasonable land management on introduced vegetation should be considered.