College of Forestry and Prataculture, Ningxia University, Yinchuan 750000, China.
Breeding Base for State Key Laboratory of Land Degradation and Ecological Restoration in Northwest China, Ningxia University, Yinchuan 750000, China.
Ying Yong Sheng Tai Xue Bao. 2024 Aug;35(8):2119-2130. doi: 10.13287/j.1001-9332.202407.017.
Understanding water use characteristics of plants and their interrelations is essential for achieving sustainable vegetation restoration of desert steppe. This study focused on five dominant plant species inhabiting two habitats: sierozem (, , and ) and aeolian sandy soil (, , and ). We analyzed δH and δO isotopes in xylem, soil water, groundwater, and precipitation. By integrating soil water content and root data at various depths, we employed the MixSIAR model to quantitatively assess water utilization characteristics. Results revealed that these plants primarily relied on soil water during the growing season, with variations in water uptake depths at different growth stages. In the sierozem habitat, exhibited significant variations in water source throughout the growing season. Early in the growing season (May to June), primarily extracted soil water from depths of 60-100 cm. During the peak growth period (July to August), water source shifted to depths of 100-200 cm, and returned to the depth of 0-20 cm by the end of the season (September). initially utilized soil water at 60-100 cm but shifted to 0-20 cm during and after peak growth. predominantly tapped into soil water at 20-60 cm early and late in the growing season, but shifted to 0-20 cm during peak growth. In the aeolian sandy soil habitat, initially utilized soil water at 60-100 cm but shifted to 0-20 cm during and after peak growth. primarily utilized soil water at 60-100 cm early and during peak growth, shifting to 100-200 cm by the end of the season. mainly relied on soil water at 20-60 cm throughout the growing season. Soil moisture, seasonal precipitation variation, and root distribution influenced vegetation water use patterns. Throughout the growing season, trees, shrubs, and herbs in the sierozem habitat exhibited hydrological niche partitioning, which facilitated their water distribution and utilization. Conversely, dominant plants in the aeolian sandy soil habitat showed hydrological niche overlap, which intensified water competition, particularly between trees and shrubs. Therefore, species traits and soil properties should be given full consideration when selecting species combinations for vegetation restoration. Introducing species combinations with complementary water use characteristics is essential for fostering species diversity and sustainable vegetation restoration in desert steppe.
了解植物的水分利用特征及其相互关系对于实现荒漠草原植被的可持续恢复至关重要。本研究聚焦于两种生境中的五种优势植物种：黑钙土（、、和）和风沙土（、、和）。我们分析了木质部、土壤水、地下水和降水的 δH 和 δO 同位素。通过整合不同深度的土壤水分含量和根系数据，我们运用 MixSIAR 模型定量评估了水分利用特征。结果表明，这些植物在生长季主要依赖土壤水，不同生长阶段的水分吸收深度存在差异。在黑钙土生境中，在整个生长季表现出显著的水源变化。在生长季早期（5 月至 6 月），主要从 60-100cm 深处提取土壤水。在生长高峰期（7 月至 8 月），水源转移到 100-200cm 深处，到生长季末期（9 月）又回到 0-20cm 深处。在生长早期和高峰期主要从 60-100cm 处利用土壤水，但在高峰期过后则利用 0-20cm 处的土壤水。在生长季早期和晚期主要从 20-60cm 处利用土壤水，但在生长高峰期则利用 0-20cm 处的土壤水。在风沙土生境中，在生长季早期和高峰期主要从 60-100cm 处利用土壤水，但在高峰期过后则利用 0-20cm 处的土壤水。在整个生长季主要从 20-60cm 处利用土壤水。土壤水分、季节性降水变化和根系分布影响植被水分利用模式。在整个生长季，黑钙土生境中的乔木、灌木和草本植物表现出水分生态位的分离，这有助于它们的水分分配和利用。相比之下，风沙土生境中的优势植物表现出水分生态位的重叠，加剧了水分竞争，特别是在乔木和灌木之间。因此，在选择植被恢复的物种组合时，应充分考虑物种特性和土壤特性。引入具有互补水分利用特征的物种组合对于促进荒漠草原的物种多样性和可持续植被恢复至关重要。
