Image Driven Hydrological Components-based Fish Habitability Modeling in Riparian Wetlands Triggered by Damming

Swades Pal,Rumki Khatun

doi:10.1007/s13157-021-01521-7

Abstract

The main focus of the current study is on assessing the habitability of some selected fishes in the Indo-Bangladesh barind tract wetland in pursuance of damming using hydrological components such as hydro-period, water depth, and water presence consistency deriving from satellite images. For pre-dam and post-dam periods, a rule-based decision tree modeling approach was used to integrate the aforementioned hydrological factors to determine habitat suitability for the chosen fishes like carp fishes, shrimps, tilapia, and catfishes. Damming has hastened the pace of wetland hydrological transformation, enhancing water presence inconsistency, shortening hydro-duration, and shallowing water depth. Based on the model, a small part of the wetland was identified as good fish habitat (16.54–39.90%) prior to damming, but virtually all portions have become the least suited for fish after damming habitability. A field survey showed that fishing quantity and growth rate was higher before such hydrological alteration but steadily decreased over the post-dam period. Image-driven hydrological parameters to estimate fish habitability are novel techniques; however, essential elements such as food availability and water quality metrics could be included to improve the result.

Highlights

Wetland, a natural capital, occupies 6% of world’s geographical land (Mitsch et al, 2013)
From the model it is very clear that a small proportion area was considered to be good fish habitat (16.54–39.90%) in pre-dam period, but after damming almost all parts have become least suitable for fish habitability
Flow reduction causes losing of tie channels for riparian wetlands which is responsible for depletion of water availability (Pal and Sarda, 2020)

Summary

Introduction

A natural capital, occupies 6% of world’s geographical land (Mitsch et al, 2013). It provides different provisional, regulating, habitat and cultural services of socio-ecological importance (Wang et al, 2020). Wetland serves as one of the major means of livelihood for developing nations like India, Bangladesh where a huge part of population is highly dependent on primary activities like fishing, agriculture, dairy farming, cattle ranching, etc. Flow reduction causes losing of tie channels for riparian wetlands which is responsible for depletion of water availability (Pal and Sarda, 2020). Eco-hydrological deficit is acute in some wetlands of Barind tract of Indo-Bangladesh (Saha and Pal, 2019); Talukdar and Pal, 2020)

Methods

Results

Discussion

Conclusion