Key Laboratory of Ecosystem Network Observation and Modelling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China.
Key Laboratory of Ecosystem Network Observation and Modelling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100190, China.
Sci Total Environ. 2022 Sep 10;838(Pt 3):156512. doi: 10.1016/j.scitotenv.2022.156512. Epub 2022 Jun 6.
Identifying ecological strategies based on functional traits can help us better understand plants' adaptations and changes in ecological processes, and thus predict the impact of climate change on ecosystems, especially in the vulnerable alpine grasslands. Herein, we investigated the plant CSR strategies of four grassland types (alpine meadows, AM; alpine meadow steppes, AMS; alpine steppes, AS; and alpine desert steppes, ADS) and its functional groups (grasses, sedges, legumes, and forbs) along the east-to-west gradient of decreasing precipitation on the northern Tibetan grasslands by using Grime's CSR (C: competitor, S: stress tolerator, and R: ruderal) analysis. Although alpine grasslands were dominated by S-strategy, our results also indicated that AM with higher water, nitrogen (N) and phosphorus (P) availability had significantly lower S-strategy values and relatively higher C- and R-strategy values (C: S: R = 6: 63: 31 %) than those in AMS (C: S: R = 3: 94: 3 %,), AS (C: S: R = 3: 87: 10 %), and ADS (C: S: R = 1: 94: 5 %). The CSR strategy values of forbs and legumes showed greater variability compared with grasses and sedges in the environmental gradient. Furthermore, water variability on the precipitation gradient eventually affected plant traits and CSR strategies through soil N and P availability and pH. Our findings highlighted that plant CSR strategies were regulated by the availability of soil resources, and plants adopted more flexible adaptation strategies in relatively resource-rich environments. This study sheds light on the mechanisms of plant adaptation to the changing environment in the alpine grasslands.
基于功能特征来识别生态策略可以帮助我们更好地理解植物在生态过程中的适应和变化，从而预测气候变化对生态系统的影响，特别是在脆弱的高山草原。在这里，我们通过 Grime 的 CSR（C：竞争者，S：压力耐受者，R：杂草）分析，研究了藏北草原从东到西降水减少的四个草原类型（高山草甸、高山草甸草原、高山草原和高山荒漠草原）及其功能群（禾本科、莎草科、豆科和杂类草）的植物 CSR 策略。尽管高山草原以 S 策略为主，但我们的结果也表明，具有较高水分、氮（N）和磷（P）供应的高山草甸的 S 策略值显著较低，而 C 策略和 R 策略值相对较高（C：S：R = 6：63：31％），而高山草甸草原（C：S：R = 3：94：3％）、高山草原（C：S：R = 3：87：10％）和高山荒漠草原（C：S：R = 1：94：5％）。与禾本科和莎草科相比，环境梯度中杂类草和豆科的 CSR 策略值表现出更大的可变性。此外，降水梯度上的水分变异性最终通过土壤 N 和 P 供应以及 pH 值影响植物性状和 CSR 策略。我们的研究结果表明，植物 CSR 策略受土壤资源供应的调节，植物在相对资源丰富的环境中采用了更灵活的适应策略。本研究揭示了植物适应高山草原变化环境的机制。
