Evaluating and Predicting the Effects of Land Use Changes on Hydrology in Wami River Basin, Tanzania

Sekela Twisa,Manfred F Buchroithner,Shija Kazumba,Mathew Kurian

doi:10.3390/hydrology7010017

Abstract

Understanding the variation in the hydrological response of a basin associated with land use changes is essential for developing management strategies for water resources. The impact of hydrological changes caused by expected land use changes may be severe for the Wami river system, given its role as a crucial area for water, providing food and livelihoods. The objective of this study is to examine the influence of land use changes on various elements of the hydrological processes of the basin. Hybrid classification, which includes unsupervised and supervised classification techniques, is used to process the images (2000 and 2016), while CA–Markov chain analysis is used to forecast and simulate the 2032 land use state. In the current study, a combined approach—including a Soil and Water Assessment Tool (SWAT) model and Partial Least Squares Regression (PLSR)—is used to explore the influences of individual land use classes on fluctuations in the hydrological components. From the study, it is evident that land use has changed across the basin since 2000 (which is expected to continue in 2032), as well as that the hydrological effects caused by land use changes were observed. It has been found that the major land use changes that affected hydrology components in the basin were expansion of cultivation land, built-up area and grassland, and decline in natural forests and woodland during the study period. These findings provide baseline information for decision-makers and stakeholders concerning land and water resources for better planning and management decisions in the basin resources’ use.

Highlights

Due to a global increase in population, a substantial rise in fluctuations in many types of land use has been documented, resulting in challenges to water resource availability [1]
These findings provide baseline information for decision-makers and stakeholders concerning land and water resources for better planning and management decisions in the basin resources’ use
It was found that the major land use changes that affected hydrology components in the basin were expansion of cultivation land, built-up area and grassland, and decline in natural forests and woodland during the study period

Summary

Introduction

Due to a global increase in population, a substantial rise in fluctuations in many types of land use (e.g., urbanization, deforestation, and agriculture) has been documented, resulting in challenges to water resource availability [1]. Basin resources have been facing severe pressure to provide for the needs of an increasing population, causing intensified agricultural practices and deforestation [2]. The future accessibility of adequate supplies of water for agricultural and human needs has become critical in many areas [3,4]. Several areas face water scarcity due to variations in land use types, pollution, agriculture, climate change, and human activities [5]. Land use changes cause adverse effects on catchments by affecting infiltration, flood peaks, evapotranspiration, groundwater recharge, sediment transportation, surface runoff, and water quality, among others [6].

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Discussion

Conclusion