荒漠植物不同功能群性状特征及其与土壤环境的关系

Traits of different functional groups of desert plants and their relationship with soil environment

研究不同功能群植物性状差异及其与土壤环境关系对于充分掌握植物的环境适应策略至关重要。以艾比湖流域为研究区,利用荒漠植物的植物高度、叶片碳、氮、磷、硫、钾、钙、钠、镁含量等9个性状,将高、低土壤水盐环境下的植物划分为5个功能群,分析不同功能群的植物组成、性状差异及其与土壤环境的关系。结果表明:(1)不同土壤水盐环境下,其植物功能群组成不同;其中白刺、胡杨和罗布麻在两个土壤水盐环境下的功能群中均存在。(2)植物的功能性状在不同土壤水盐环境下也发生了适应性的变化。高土壤水盐环境下3个功能群的植物高度、叶片碳、氮、磷和钙含量显著高于低土壤水盐环境功能群(P<0.05);低土壤水盐环境下2个功能群的植物叶片硫、钠和镁含量高于高土壤水盐环境功能群。(3)土壤含水量(SVWC)、电导率(EC)、pH以及土壤磷含量对荒漠植物功能性状影响较大。在高土壤水盐环境下,EC、pH与植物高度,叶片钾、钙含量正相关,与叶片硫含量负相关;在低土壤水盐环境下,SVWC、EC与植物高度呈显著正相关(P<0.05)。研究有助于理解荒漠植物对极端环境的适应对策,为保护荒漠地区生物多样性提供理论依据。

Grouping plant species sharing similar structure and function would increase our ability to predict vegetation dynamics and ecosystem function under natural or man-induced environmental changes at a global scale.At the same time,grouping plant species may provide some degrees of simplification to understand the ecological function of plants in key ecosystem processes.Studying differences in plant traits of different functional groups and their relationship with soil environment is crucial for fully grasping the environmental adaptation strategies of plants.However,meaningful variation in functional characteristics that might help group plants across narrow environmental gradients,such as those of arid ecosystems,were scarcely described.In this study,plants in high and low soil moisture and salinity environments in the Ebinur Lake Basin were divided into five functional groups according to nine morphological and chemical traits related to plant persistence and stress resistance,such as plant height and the contents of leaf carbon,nitrogen,phosphorus,sulfur,potassium,calcium,sodium,and magnesium.Besides,the plant composition,traits difference,and relationship with soil environment of different functional groups were analyzed.The results showed that:(1)the composition of plant functional groups was different in different soil moisture and salinity environments;Nitraria tangutorum,Populus euphratica,and Apocynum venetum were detected in both environments.(2)Plant functional traits changed adaptively in high and low soil moisture and salinity environments.The plant height and leaf carbon,nitrogen,phosphorus,and calcium contents of three functional groups in the high soil moisture and salinity environment were significantly higher than those in the low soil moisture and salinity environment(P<0.05);The contents of sulfur,sodium,and magnesium in leaves of two functional groups in the low soil moisture and salinity environment were higher than those in the high soil moisture and salinity environment.(3)Soil volume water content(SVWC),electrical conductivity(EC),pH,and soil phosphorus concentration had the greater impact on the functional traits of desert plants.In the high soil moisture and salinity environment,soil EC and pH were positively correlated with plant height and leaf potassium and calcium contents,while negatively correlated with leaf sulfur content.In the low soil moisture and salinity environment,SVWC and EC were significantly positively correlated with plant height(P<0.05).The study helps to understand the adaptation responses of desert plants to the extreme environments and provides a theoretical basis for the conservation of biodiversity in desert areas.