Botanical Garden, University of Wrocław, Wrocław, Poland.
MTA Centre for Ecological Research, Institute of Ecology and Botany, Vácrátót, Hungary.
PLoS One. 2018 May 17;13(5):e0197363. doi: 10.1371/journal.pone.0197363. eCollection 2018.
Intermittently wet meadows of the Molinion alliance, as with many other grasslands of high-nature value, have become increasingly exposed to abandonment due to their low economic value. The potential consequences of land abandonment are the decrease in species diversity and environmental alterations. The issue of land-use induced changes in plant species composition and soil physico-chemical parameters have been rarely studied in species-rich intermittently wet grasslands. In this study we attempt to i) to identify determinants of plant species composition patterns and ii) to investigate the effect of cessation of mowing on vegetation composition and soil properties. The study was conducted in an area of 36 ha covered with Molinion meadows, comprising of mown sites and sites that were left unmown for 10 years. In total, 120 and 80 vegetation plots were sampled from mown and unmown sites, respectively. In these plots we measured plant community composition and soil physico-chemical parameters. The results have shown that the two groups of variables (soil properties and management) differ considerably in their ability to explain variation in plant species data. Soil variables explained four-fold more variation in plant species composition than management did. The content of soil organic matter, moisture, total nitrogen and exchangeable forms of potassium, calcium and magnesium were significantly higher in mown than in unmown grassland systems. The results revealed that soil organic matter was the component of the soil most strongly affected by management, followed by moisture, magnesium, calcium and potassium in that order. Each of these soil parameters was negatively correlated with the abundances of woody plants and invasive species. We concluded that low-intensity, late time of mowing is suitable grassland management practice to ensure high plant species diversity and sustainability of the grassland ecological system while cessation of mowing not only lead to reduced plant species richness and diversity, but also to reduced nutrient levels in grassland soils.
间歇性湿润草地的 Molinion 联盟，与许多其他高自然价值的草原一样，由于其经济价值低，越来越容易被放弃。土地废弃的潜在后果是物种多样性的减少和环境的改变。在物种丰富的间歇性湿润草原中，很少研究土地利用引起的植物物种组成和土壤理化参数变化的问题。在本研究中，我们试图：i）确定植物物种组成模式的决定因素，ii）研究停止割草对植被组成和土壤特性的影响。该研究在一个 36 公顷的 Molinion 草地地区进行，包括割草地和未割草 10 年的草地。总共从割草地和未割草地采集了 120 和 80 个植被样方。在这些样方中，我们测量了植物群落组成和土壤理化参数。结果表明，两组变量（土壤性质和管理）在解释植物物种数据的变化方面有很大的不同。土壤变量比管理变量解释了植物物种组成变化的四倍多。割草地的土壤有机质、水分、总氮和可交换的钾、钙、镁含量明显高于未割草地。结果表明，土壤有机质是受管理影响最大的土壤成分，其次是水分、镁、钙和钾。这些土壤参数中的每一个都与木本植物和入侵物种的丰度呈负相关。我们得出的结论是，低强度、晚时间割草是适合草地管理的实践，可以确保高的植物物种多样性和草地生态系统的可持续性，而停止割草不仅会导致植物物种丰富度和多样性的减少，还会导致草地土壤养分水平的降低。
