Water level fluctuations in sub-tropical floodplain wetlands of Nepal affect the types of plants that grow there. A study in Koshi Tappu found that high water levels in summer support floating invasive plants, while medium and low levels in autumn and winter favor submerged plants. Low water levels in spring help emergent and amphibian plants thrive. Overall, as water levels rise, plant diversity decreases but total plant biomass increases. Water depth and water quality factors like temperature, oxygen levels, and nutrients are closely linked to the types of plants found in the wetlands. Managing water levels can help protect wetland ecosystems and maintain biodiversity.