Role of Flooding Patterns in the Biomass Production of Vegetation in a Typical Herbaceous Wetland, Poyang Lake Wetland, China

Abstract

Flooding is an important factor influencing the biomass production of vegetation in natural wetland ecosystems. However, how biomass production is linked to flooding patterns in wetland areas remains unclear. We utilized gauging station data, a digital elevation model, vegetation survey data, and a Landsat 8 image to study the effects of average inundation depth (AID) and inundation duration (IDU) of flooding on end-ofseason biomass of vegetation in Poyang Lake wetland, in particular, after operation of Three Gorges Dam. The end-of-season biomass of wetland vegetation showed Gaussian distributions along both the AID and IDU gradients. The most favorable flooding conditions for biomass production of vegetation in the wetland had an AID ranging from 3.9 to 4.0 m and an IDU ranging from 39% to 41%. For sites with a lower AID (<3.9 m; IDU < 39%), the end-of-season biomass values were positively related, whereas for sites with a higher AID (4.0 m; IDU > 41%), the end-of-season biomass values were negatively related. After the operation of the Three Gorges Dam, flooding patterns characterized by AID and IDU of the Poyang Lake wetland were significantly alleviated, resulting in a mixed changing trend of vegetation biomass across the wetland. Compared with 1980-2002, the increase of end-of-season biomass in lower surfaces caused by the alleviated flooding pattern far exceeded the decrease of endof-season biomass in higher surfaces, resulting in an end-of-season biomass increase of 1.0%-6.7% since 2003. These results improved our understanding of the production trends of vegetation in the wetland and provided additional scientific guidance for vegetation restoration and wetland management in similar wetlands.

Invasive Plants and Species Richness Impact Litter Decomposition in Riparian Zones

“…The effect of changing the plant community means accelerating or slowing down the decomposition rate of the litter mixture (Zhang et al, 2014 ). Many studies refer to the acceleration or slowing down of the litter mixture decomposition rate as a non-additive effect (Dai et al, 2020 ). The introduction of exotic plants into the native plant community has accelerated the mass loss and release of nitrogen from native plant litter (Liu et al, 2020 ).…”

Impact of Short‐Term Hydrological Components on Landscape Pattern of Waterbird Habitat in Floodplain Wetlands

“…Waterbirds (e.g., Anatidae , Scolopacidae , and Charadriidae ) in wetlands prefer to roost in meadows. Flood processes affect the plant community through the timing (e.g., maximum continuous flooding days (MFD)) and magnitude (e.g., average flooding depth (AFD) of flooding events (Butterfield et al., 2018; X. Dai et al., 2020). Drought could increase the heterogeneity of vegetation distribution in floodplain wetlands (Capon & Reid, 2016), which can be characterized by maximum continuous drought days (MDD) (Tosunoglu & Kisi, 2016).…”

“…Waterbirds (e.g., Anatidae, Scolopacidae, and Charadriidae) in wetlands prefer to roost in meadows. Flood processes affect the plant community through the timing (e.g., maximum continuous flooding days (MFD)) and magnitude (e.g., average flooding depth (AFD) of flooding events (Butterfield et al, 2018;X. Dai et al, 2020).…”

“…Hydrological components could be divided into long‐term hydrological components (i.e., annual or inter‐annual scale) and short‐term hydrological components (i.e., seasonal, monthly, or daily scale). It has been widely reported that the long‐term hydrological components significantly affect biomass and diversity of vegetation, community characteristics of invertebrate, and landscape patterns of wetlands, thus affecting waterbird habitats (X. Dai et al., 2020; Dube et al., 2019; Maietta et al., 2020; Solórzano et al., 2020; X. Zhang et al., 2021). X. Dai et al.…”

“…Short‐term hydrological components may better characterize these rapid short‐term changes, because they interact with the landscape patterns directly related to the diversity of vegetation and community characteristics of invertebrate (Brower et al., 2017; Riis & Hawes, 2002; Wu et al., 2019). However, knowledge about the effects of short‐term hydrological components on waterbird habitats is limited (X. Dai et al., 2020).…”