滑坡体成土作用早期影响生物有效磷(Bio-P)含量的主要因素  

Major Factors Regulating Bioavailable Phosphorus(Bio-P)Content at Early Stages of Pedogenesis in Landslide Deposits

作　　者：何晓丽 何俊波 吴艳宏[2] HE Xiaoli;HE Junbo;WU Yanhong(College of Resource Environment and Tourism,Hubei University of Arts and Science,Xiangyang 441053,Hubei,China;Institute of Mountain Hazards and Environment,Chinese Academy of Sciences&Ministry of Water Resources,Chengdu 610213,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]湖北文理学院资源环境与旅游学院,湖北襄阳441053 [2]中国科学院、水利部成都山地灾害与环境研究所,成都610213 [3]中国科学院大学,北京100049

出　　处：《山地学报》2024年第6期781-790,共10页Mountain Research

基　　金：湖北省自然科学基金(2022CFB783)。

摘　　要：生物有效磷(Bio-P)是植物生长的关键营养元素,关系到植物的生长态势和生产力水平,在土壤发育和生态系统功能调控中发挥核心作用。其释放、吸收及固定过程受到母岩类型、气候条件(特别是温度和降水状况)、土壤微生物活性及其酶促作用等多重因素的共同制约。然而,这些影响因素的交互作用及其对成土早期Bio-P循环的影响尚未得到充分阐释。本研究选取了川西地区14个年龄为5~30 a的滑坡堆积体,通过研究土壤微生物群落、母质特性及气候条件对Bio-P含量的影响,旨在探究成土早期影响Bio-P浓度的机制。研究结果显示,(1)滑坡堆积体土体Bio-P的含量呈现显著的空间异质性。大渡河泸定段与岷江上游地区的Bio-P浓度存在统计学上的显著差异(U=48,p=0.0012),前者质量浓度区间为41.18~60.02 mg·kg^(-1),显著高于后者的27.88~44.19 mg·kg^(-1)。(2)在影响Bio-P含量变异的诸多因素中,气候、母质及微生物的贡献各不相同,其中气候条件在土壤磷循环调控中占据主导地位,其解释度达到57%。温度是决定Bio-P浓度的关键因素,其重要性权重为0.24。温度不仅直接通过调控土壤中磷的化学过程(涵盖溶解、吸附与沉淀等)影响Bio-P含量,还间接通过增强土壤微生物活性发挥作用,且其直接效应值0.49明显高于间接效应值0.30。(3)在生态系统管理与恢复实践中,应将温度调控作为成土早期调控土壤Bio-P浓度的基本策略。本研究成果可为土壤恢复和制定生态保护策略提供科学依据。Bioavailable phosphorus(Bio-P)is a decisive nutrient element in soil,governing plant growth and productivity levels,and plays a central role in soil evolution and regulation of ecosystem functions.Its release,absorption,and fixation processes are regulated by a combination of factors such as parent rock type,climatic conditions(especially temperature and precipitation),soil microbial activity and its enzymatic role.Unfortunately,the interactions among these influencing factors and their effects on Bio-P cycling during early pedogenesis had not been fully elucidated.In this study,soils at 14 landslide deposits with ages ranging from 5 to 30 years in western Sichuan,China were collected for testing,and the effects of soil microbial community,parent rock properties and climatic conditions on Bio-P content were studied,so as to explore the mechanism of influencing Bio-P concentration in the early stage of soil formation.(1)The content of Bio-P in the soils of landslide deposits exhibited significant spatial heterogeneity.There was a statistically significant difference in Bio-P concentrations between the soils sampled at the Luding section of the Daduhe River and the upper reaches of the Minjiang River(U=48,p=0.0012).The concentration range of the former was 41.18-60.02 mg·kg^(-1),which was significantly higher than that of the latter,27.88-44.19 mg·kg^(-1).(2)Among the many factors influencing the variability of Bio-P content,the contributions of climate,parent rock and microorganisms varied,with climatic conditions dominating the regulation of soil phosphorus cycle,with a 57%degree of explanation.Temperature was a key factor determining Bio-P concentration with a relative importance weight of 0.24.Temperature not only affected Bio-P content directly by regulating the chemical processes of phosphorus in soils(covering dissolution,adsorption and precipitation,etc.),but also indirectly by enhancing soil microbial activity,and its direct effect(0.49)was significantly higher than the indirect effect(0.30).(3)Temperatu

关 键 词：滑坡堆积体 成土早期 岷江上游 大渡河泸定段 生物有效磷 

分 类 号：P951[天文地球—自然地理学]