Land Cover, Land Use, and Climate Change Impacts on Endemic Cichlid Habitats in Northern Tanzania

Abstract

Abstract:Freshwater ecosystems are among the most threatened on Earth, facing environmental and anthropogenic pressures often surpassing their terrestrial counterparts. Land use and land cover change (LUCC) such as degradation and fragmentation of the terrestrial landscape negatively impacts aquatic ecosystems. Satellite imagery allows for an impartial assessment of the past to determine habitat alterations. It can also be used as a forecasting tool in the development of species conservation strategies through models based on ecological factors extracted from imagery.In this study, we analyze Landsat time sequences to quantify LUCC around three freshwater ecosystems with endemic cichlids in Tanzania. In addition, we examine population growth, agricultural expansion, and climate change as stressors that impact the habitats. We found that the natural vegetation cover surrounding Lake Chala decreased from 15.5% (1984) to 3.5% (2015). At Chemka Springs, we observed a decrease from 7.4% to 3.5% over the same period. While Lake Natron had minimal LUCC, severe climate change impacts have been forecasted for the region. Subsurface water data from the Gravity Recovery and Climate Experiment (GRACE) satellite observations further show a decrease in water resources for the study areas, which could be exacerbated by increased need from a growing population and an increase in agricultural land use.

Quantitatively Assessing the Future Land-Use/Land-Cover Changes and Their Driving Factors in the Upper Stream of the Awash River Based on the CA–Markov Model and Their Implications for Water Resources Management

“…Changes in LULC, such as the fragmentation and degradation of terrestrial landscape, adversely affect the quality of aquatic ecosystems. Freshwater ecosystems are some of the most threatened ecosystems on the planet, facing human and environmental pressures [141]. For example, due to the increasing pressure and scarcity of freshwater resources, the pollution of freshwater resources is attracting global attention [142].…”

Newly discovered cichlid fish biodiversity threatened by hybridization with non‐native species

“…Freshwater ecosystems are undergoing rapid changes in biodiversity due to the interacting effects of habitat degradation, over‐exploitation, water pollution, flow modification and species invasion (Dudgeon et al., 2006; Millennium Ecosystem Assessment, 2016; Sala et al., 2000). As human population sizes continue to rise, and climate change becomes an ever‐increasing threat, these impacts are predicted to grow (Arroita et al., 2017; Kalacska et al., 2017; Martinuzzi et al., 2014). A specific issue is hybridization between introduced species and native fish species.…”

From ecology to remote sensing: using animals to map land cover

“…Land cover mapping is one of the main applications of remote sensing and a clear requirement of environmental monitoring initiatives. Among others, land cover is essential in climate change mitigation (Dirmeyer et al 2010;Kalacska et al 2017), habitat management (Lang et al 2015;Lucas et al 2015;Vaz et al 2015) and food security monitoring (Verburg et al 2013;Whitcraft et al 2015;Brown 2016), demanding its regular update in a consistent and systematic manner .…”