Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149 Münster, Germany.
Institute of Landscape Ecology, University of Münster, Heisenbergstraße 2, 48149 Münster, Germany.
Sci Total Environ. 2021 Feb 10;755(Pt 2):142659. doi: 10.1016/j.scitotenv.2020.142659. Epub 2020 Oct 2.
Fire is a major driver of global vegetation patterns. It strongly reduces litter and thus alters physical and chemical properties of the environment. Studies investigating the interplay of fire and litter are scarce, and wetland ecosystems are strongly under-represented in research focusing on litter dynamics. We present data on short-term effects of fires in floodplain wetlands along the Amur River in the Russian Far East, an area with a high fire recurrence rate. We analysed vegetation and plant growth patterns as well as soil temperature and nutrient concentrations on recently burnt and unburnt control plots. Directly after fire, litter was reduced by more than 50% on burnt plots. This effect was no longer visible 15 months after fire, probably due to the high productivity of the floodplain ecosystem. Litter was found to act as a key determinant in the net of direct and indirect fire effects, by influencing early plant growth patterns of herbs and grasses. Furthermore, litter removal through fire significantly increased plant species diversity and soil temperature. Contrary, N and P concentrations in living plant biomass of grasses and herbs decreased with decreasing litter cover. Combustion during burning seems to be responsible for the negative direct fire impacts on nutrient concentrations, which were found for N and Mg. Litter removal through fire can strongly affect diversity patterns, dominance structures, and nutrient cycling in wetlands. With increasing fire frequency in the course of global change, significant structural and compositional changes in herbaceous wetland vegetation must be anticipated and the studied ecosystem may shift to reinforced N-limitation.
火是全球植被格局的主要驱动因素。它强烈减少凋落物，从而改变环境的物理和化学性质。研究火与凋落物相互作用的研究很少，而湿地生态系统在关注凋落物动态的研究中代表性严重不足。我们提供了俄罗斯远东地区阿穆尔河漫滩湿地火灾的短期影响的数据，该地区火灾复发率很高。我们分析了近期火烧和未火烧对照样地上的植被和植物生长模式以及土壤温度和养分浓度。火灾后，凋落物在火烧样地上减少了 50%以上。15 个月后，这种效应不再明显，这可能是由于漫滩生态系统的高生产力。凋落物通过影响草本植物和草类的早期植物生长模式，成为直接和间接火效应网络中的关键决定因素。此外，通过火烧去除凋落物可显著增加植物物种多样性和土壤温度。相反，随着凋落物覆盖的减少，草本植物和草类活植物生物量中的 N 和 P 浓度降低。燃烧似乎是导致养分浓度直接受火影响的原因，其中 N 和 Mg 受到影响。通过火烧去除凋落物可以强烈影响湿地的多样性模式、优势结构和养分循环。随着全球变化中火的频率增加，草本湿地植被必须预期到显著的结构和组成变化，而研究中的生态系统可能会转向加强的 N 限制。
