Zhang Shuqiao, Shu Langlang, Liu Wendou, Wang Zizhi, Wu Wengui, Liao Shengxi
Institute of Highland Forest Science, Chinese Academy of Forestry, Kunming, Yunnan, China.
School of Agriculture, Food and Ecosystem Sciences, Faculty of Science, The University of Melbourne, Creswick, VIC, Australia.
Front Plant Sci. 2025 Jun 3;16:1582124. doi: 10.3389/fpls.2025.1582124. eCollection 2025.
Grasslands exhibit significant variability in productivity across fine spatial scales, which is crucial for understanding terrestrial carbon cycling, particularly under global climate change. While alpine grasslands have been extensively studied, subalpine wet grasslands (2000-4000 m) remain underexplored. Investigating their productivity and responses to environmental factors is essential for a comprehensive understanding of ecosystem dynamics in these regions.
We applied destructive sampling techniques, optimized grassland investigation, and employed multivariate modeling to examine how different environmental variables influence grassland biomass. An 80-plot field-based dataset was established in a subalpine wet grassland.
Our findings reveal that plant biomass peaked at elevations between 3400 and 3500 m. Belowground biomass accounted for 85% of total productivity, with the majority contributed by dominant species. Vegetation-related variables, such as coverage and root/shoot ratio, were the primary determinants of aboveground biomass, whereas soil properties were key regulators of belowground biomass. Although direct and indirect effects of landform and climatic factors influenced total biomass, the patterns of total and belowground biomass were consistent. The results underscore the significant positive impact of vegetation cover, root-to-shoot ratio, and soil conditions on grassland productivity. Notably, soil organic carbon, water content, and the nitrogen-to-phosphorus ratio affected belowground biomass.
These insights enhance our understanding of the intricate interactions between climate, soil, landform, and plant communities in influencing grassland biomass and highlight the importance of preserving plant diversity and maintaining optimal soil conditions in subalpine wet grasslands. One grassland does not fit all; fine-scale classification is essential to capture the variability in productivity across different grassland types.
草原在精细空间尺度上生产力存在显著差异，这对于理解陆地碳循环至关重要，尤其是在全球气候变化背景下。虽然高山草原已得到广泛研究，但亚高山湿草原（海拔2000 - 4000米）仍未得到充分探索。研究其生产力及其对环境因素的响应对于全面理解这些地区的生态系统动态至关重要。
我们应用破坏性采样技术、优化草原调查，并采用多变量建模来研究不同环境变量如何影响草原生物量。在一个亚高山湿草原建立了一个基于80个样地的野外数据集。
我们的研究结果表明，植物生物量在海拔3400至3500米之间达到峰值。地下生物量占总生产力的85%，其中大部分由优势物种贡献。与植被相关的变量，如覆盖度和根冠比，是地上生物量的主要决定因素，而土壤性质是地下生物量的关键调节因子。尽管地形和气候因素的直接和间接影响影响了总生物量，但总生物量和地下生物量的模式是一致的。结果强调了植被覆盖、根冠比和土壤条件对草原生产力的显著积极影响。值得注意的是，土壤有机碳、含水量和氮磷比对地下生物量有影响。
这些见解增强了我们对气候、土壤、地形和植物群落之间复杂相互作用对草原生物量影响的理解，并突出了保护亚高山湿草原植物多样性和维持最佳土壤条件的重要性。一种草原并不适用于所有情况；精细尺度分类对于捕捉不同草原类型生产力的变异性至关重要。
