短期施氮对新疆伊犁半干旱山地草原植物群落及物种多样性的影响OA
Effects of short-term nitrogen application on plant communities and species diversity in semiarid mountain grasslands of Yili,Xinjiang
为探究新疆伊犁半干旱山地草原植物群落特征对短期氮添加的响应规律,本研究以伊犁河谷托乎拉苏草原为研究对象,设置对照组(CK)及4个施氮水平(N1:50 kg·hm-2·a-1、N2:100 kg·hm-2·a-1、N3:150 kg·hm-2·a-1和N4:200 kg·hm-2·a-1),通过一个生长季试验,分析不同水平氮输入对群落地上生物量、成员型和物种多样性的影响,以期阐明短期施氮提升地上生物量的关键路径.结果表明:施氮对地上生物量的影响呈单峰型变化,N3处理最优,较CK处理显著提升52.08%,优势种鸭茅生物量较CK处理提升132.12%,群落高度、盖度同步显著增加,而群落密度无显著差异.氮添加显著改变了物种多样性格局,优势种鸭茅重要值在N3处理下较CK处理提升65.01%,主要伴生种白三叶的重要值在N4处理下较CK处理下降65.54%.群落多样性随施氮水平的提高总体呈先降低后升高趋势,N3处理下的群落多样性最低.Mantel检验显示,物种多样性主要受亚优势种生物量和主要伴生种密度的影响.结构方程模型显示,氮添加仅对优势种及亚优势种产生显著正向直接效应.综上所述,当施氮量为150 kg·hm-2·a-1时,对伊犁半干旱山地草原植被的恢复效果最好.
To investigate the response patterns of plant communities in the semiarid mountain grasslands of Yili,Xinjiang,to short-term nitrogen application,this study examined the Tohulasu Grassland in the Yili River Val-ley.Four nitrogen application rates(N1:50 kg·hm-2·a-1,N2:100 kg·hm-2·a-1,N3:150 kg·hm-2·a-1,and N4:200 kg·hm-2·a-1)were compared with a control group.Over one growing season,the effects of different nitrogen inputs on community aboveground biomass,community composition,and species diversity were analyzed to elu-cidate the key pathways through which short-term nitrogen application enhances aboveground biomass.Nitrogen application exerted a unimodal effect on aboveground biomass,with N3 treatment yielding the optimal result,a 52.08%increase relative to the control.The biomass of the dominant species,Dactylis glomerata,increased by 132.12%relative to the control.There were significant increases in community height and cover,but not in com-munity density.Nitrogen application caused significant alteration in species diversity patterns:The importance value of D.glomerata increased by 65.01%under the N3 treatment relative to the control,whereas the impor-tance value of the primary associate species,Trifolium repens,decreased by 65.54%under the N4 treatment rela-tive to the control.Overall,community diversity first decreased and then increased as the nitrogen application rate increased,with the lowest diversity observed under the N3 treatment.Mantel tests revealed that species diversity was regulated primarily by the biomass of subdominant species and the density of dominant companion species.Structural equation modeling indicated that nitrogen application exerted significant,positive,and direct effects on-ly on dominant and subdominant species.Overall,a nitrogen rate of 150 kg·hm-2·a-1 was most effective for vege-tation restoration in the semiarid mountain grasslands of Yili,Xinjiang.
陈月芳;李玉乐;李政升;牛克昌;周会程;提力哈吾里·达合木拜;巴雅尔塔;童永尚
伊犁师范大学生物科学与技术学院,新疆伊犁河谷资源植物保护与利用重点实验室,新疆 伊宁 835000伊犁师范大学生物科学与技术学院,新疆伊犁河谷资源植物保护与利用重点实验室,新疆 伊宁 835000伊犁师范大学生物科学与技术学院,新疆伊犁河谷资源植物保护与利用重点实验室,新疆 伊宁 835000伊犁师范大学生物科学与技术学院,新疆伊犁河谷资源植物保护与利用重点实验室,新疆 伊宁 835000伊犁哈萨克自治州草原工作站,新疆 伊宁 835000伊宁县林业和草原局,新疆 伊宁 835100伊犁师范大学生物科学与技术学院,新疆伊犁河谷资源植物保护与利用重点实验室,新疆 伊宁 835000伊犁师范大学生物科学与技术学院,新疆伊犁河谷资源植物保护与利用重点实验室,新疆 伊宁 835000
伊犁河谷施氮量群落成员型物种多样性
Yili River Valleynitrogen application ratecommunity element typespecies diversity
《干旱区研究》 2026 (5)
1001-1012,12
国家自然科学基金项目(32560918)伊犁师范大学高层次人才引进启动基金(2024RCYJ28)
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