干旱区地理2025，Vol.48Issue(7)：1176-1184,9.DOI:10.12118/j.issn.1000-6060.2024.801
黄土丘陵区露天煤矿复垦生态系统先锋树种水分利用效率
Water use efficiency of pioneer tree species in reclamation ecosystem of open-pit coal mine in loess hilly region
摘要
Abstract
Plant water-use efficiency(WUE),which measures the balance between carbon assimilation and water transpiration,serves as a vital indicator of how plants adapt to environmental constraints.This study investigated the dynamics of leaf WUE in pioneer tree species within a reclaimed ecosystem at the Pingshuo open-pit coal mine of Shanxi Province,a representative site in the loess hilly region of China.We focused on three dominant pi-oneer species:Pinus tabuliformis,Ulmus pumila,and Robinia pseudoacacia,across a chronosequence of reclama-tion ages(5,15,20,and 28 years).The study involved determining leaf carbon(C)and nitrogen(N)concentra-tions,C/N ratios,and long-term WUE as inferred from stable carbon isotope composition(δ13C).We also ana-lyzed the relationship between leaf C/N stoichiometry and WUE.The results revealed the following.(1)Leaf C and N concentrations in R.pseudoacacia and U.pumila generally increased with reclamation age,whereas P.tab-uliformis peaked in C and N levels at 15 and 20 years,respectively.P.tabuliformis had a significantly higher leaf C concentration and C/N ratio compared to U.pumila(P<0.05)but a lower N concentration compared to the oth-er two tree species(P<0.05).R.pseudoacacia maintained the highest leaf N concentration among the species(P<0.05).(2)Intra-specific WUE varied significantly(P<0.05)with reclamation age:P.tabuliformis had the highest WUE at five years and the lowest at 28 years;U.pumila peaked at 28 years and was at its minimum at five years;R.pseudoacacia reached its maximum WUE at 15 years and minimum at five years.Inter-specifically,P.tabuli-formis consistently exhibited higher WUE than both U.pumila and R.pseudoacacia.(3)Across all three species,leaf WUE showed significant positive correlations with leaf C concentration and C/N ratio,whereas its correla-tion with leaf N concentration was insignificant.These findings elucidate the species-specific WUE characteris-tics and adaptive physiological adjustments of pioneer trees during vegetation succession in the Pingshuo re-claimed mine area,offering a theoretical foundation for vegetation restoration efforts in open-pit coal mines with-in the loess hilly region.关键词
平朔露天煤矿/水分利用效率/稳定同位素技术/养分含量Key words
Pingshuo open-pit coalmine/water use efficiency/stable isotope technology/nutrient content引用本文复制引用
王霜,原野,袁媛,李倩,赵嘉瑜,杨蓉欣,杨雨青..黄土丘陵区露天煤矿复垦生态系统先锋树种水分利用效率[J].干旱区地理,2025,48(7):1176-1184,9.基金项目
国家自然科学基金项目(41907408) （41907408）
山西省基础研究计划项目(202303021211138)资助 （202303021211138）
