摘要
白桦作为祁连山东部地区的关键先锋树种,正面临林分植被退化的严峻威胁。准确评估该地区白桦天然林土壤质量对于维持祁连山生态平衡及推动区域可持续发展具有重要意义。基于此,本研究以不同林分密度(D1:0-200株/hm^(2);D2:200-400株/hm^(2);D3:400-600株/hm^(2);D4:600-900株/hm^(2);D5:900-1500株/hm^(2);D6:1500-2100株/hm^(2))白桦天然林林下土壤作为研究对象,通过测定其理化性质,分析不同林分密度白桦林下土壤理化性质差异,通过构建最小数据集评价林下土壤质量,结合植物-土壤耦合与生态系统多功能性,深入探究了林分密度对祁连山东部白桦天然林土壤质量的影响机制。结果表明:(1)不同林分密度下,土壤质量含水量、有机碳、全磷、全氮含量存在显著差异(P<0.05)。(2)基于最小数据集的构建发现,全氮、孔隙度、碱解氮、粉粒、含水量、砂粒以及速效磷是影响白桦天然林下土壤质量的关键因素。(3)白桦林不同林分密度土壤质量指数介于0.30-0.62,土壤质量综合排名为D4>D2>D1>D3>D6>D5。(4)土壤质量指数与物种丰富度和Shannon-Wiener多样性呈显著正相关(P<0.01),白桦林下植物-土壤耦合度平均为0.60,属于弱协调。(5)随着林分密度的增加,生态系统多功能性指数逐渐降低,与土壤质量指数的变化趋势一致,验证了构建的最小数据集的科学性和实用性。综上,600-900株/hm^(2)的林分密度下,白桦天然林下土壤质量最佳。本研究不仅为白桦天然林生态保护和恢复工作提供了有效的土壤质量评价模型及密度参考,也为祁连山东部的生态保护和恢复工作提供了理论支撑。
Betula platyphylla,as a key pioneer species in the eastern Qilian Mountains,is facing severe threats from forest vegetation degradation.Accurately assessing the soil quality of natural Betula platyphylla forests in this region is crucial for maintaining ecological balance in the Qilian Mountains and promoting sustainable development in the area.Based on this,the study focused on the understory soil of natural Betula platyphylla forests under different stand densities(D1:0-200 trees/hm^(2);D2:200-400 trees/hm^(2);D3:400-600 trees/hm^(2);D4:600-900 trees/hm^(2);D5:900-1500 trees/hm^(2);D6:1500-2100 trees/hm^(2))as the research object.To investigate how stand density influences soil quality,we measured soil physicochemical properties in plots and analyzed soil quality differences across these stand densities.A minimum data set(MDS)was then developed to evaluate soil quality.By integrating plant-soil coupling and ecosystem multifunctionality,we explored the impact of stand density on soil quality and the mechanisms behind it.The results indicated:(1)Soil water content,organic carbon,total phosphorus,and total nitrogen content significantly differed among stand densities(P<0.05).(2)Based on the MDS,total nitrogen,total porosity,alkaline hydrolysis of nitrogen,silt,soil water content,sand,and available phosphorus were key factors influencing soil quality.(3)The soil quality index ranged from 0.30 to 0.62,ranking of soil quality was D4>D2>D1>D3>D6>D5.(4)The soil quality index was positively and significantly correlated(P<0.01)with species richness and the Shannon-Wiener diversity index.The average plant-soil coupling degree was 0.60,indicating weak coordination between the two.(5)As stand density increased,the ecosystem multifunctionality index decreased,following a similar trend as the soil quality index.This pattern supported the validity of the MDS model.In conclusion,the best soil quality was found under natural Betula platyphylla forests with a stand density of 600-900 trees/hm^(2).This study provides an effective soil quality evaluation model and density reference for the ecological protection and restoration of natural Betula platyphylla forests by constructing a Minimum Data Set(MDS).
作者
鲁雅雯
石正阳
高佳文
邹星晨
贺康宁
LU Yawen;SHI Zhengyang;GAO Jiawen;ZOU Xingchen;HE Kangning(Soil and Water Conservation College,Beijing Forestry University,Beijing 100083,China;Engineering Research Center of Forestry Ecological Engineering,Beijing Forestry University,Beijing 100083,China)
出处
《生态学报》
北大核心
2025年第15期7603-7615,共13页
Acta Ecologica Sinica
基金
青海省科技厅重点研发与转化项目(2022-SF-160)。
关键词
白桦天然林
土壤健康
河湟谷地
生态系统多功能性
最小数据集
natural Betula platyphylla forest
soil health
Huangshui Valley
ecosystem multifunctionality index
the minimum data set
