Wetlands 54 Wetland ecology 30 Agronomy 14 Wetland management 13 Botanical science 12 Ecology 12 Dissertations, Academic (Ph.D) 9 Mangrove swamp ecology-- Salt water wetland, forest ecology 9 Wetland conservation 9 Wetland Ecology & Ecosystems 8 Applied numerical analysis-- Applied mathematics 7 Natural resources 6 Remote sensing 6 Agriculture 5 Differential equations-- Analysis-- Mathematics 5 History 5 Hydrology 5 Rice 5 Soil Science and Agricultural Chemistry 5 Thesis (Ph.D)-Environmental science 5 Aquatic ecology 4 Biodiversity 4 Biodiversity conservation 4 Conservation 4 Constructed wetlands 4 Economics 4 India 4 Kerala 4 Plant physiology 4 Wetland plants 4