Impact of landscape pattern changes on hydrological ecosystem services in the Beressa watershed of the Blue Nile Basin in Ethiopia

Hamere Yohannes; Teshome Soromessa; Mekuria Argaw; Ashraf Dewan

doi:10.1016/j.scitotenv.2021.148559

Impact of landscape pattern changes on hydrological ecosystem services in the Beressa watershed of the Blue Nile Basin in Ethiopia

Sci Total Environ. 2021 Nov 1:793:148559. doi: 10.1016/j.scitotenv.2021.148559. Epub 2021 Jun 22.

Authors

Hamere Yohannes¹, Teshome Soromessa², Mekuria Argaw², Ashraf Dewan³

Affiliations

¹ Department of Natural Resources Management, College of Agriculture and Natural Resource Sciences, Debre Berhan University, Debre Berhan, Ethiopia; Center for Environmental Sciences, College of Natural Sciences, Addis Ababa University, Addis Ababa, Ethiopia. Electronic address: hamere.yohannes@aau.edu.et.
² Center for Environmental Sciences, College of Natural Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
³ Spatial Sciences Discipline, School of Earth and Planetary Sciences, Curtin University, Perth, Australia.

PMID: 34328959
DOI: 10.1016/j.scitotenv.2021.148559

Abstract

Landscape pattern changes are mostly due to human activities, and such changes often affect ecosystem functions and services. This study was conducted to evaluate the response of hydrological ecosystem services (HESs) to structural landscape changes. Spatiotemporal changes in two specific HES indicators, water yield (WY) and sediment export (SE), were quantified by analyzing historic (1972-2017) and projected land use/land cover changes (2017-2047). The Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) Model was used for this purpose. Results indicated that WY and SE changed significantly (p ˂ 0.01) during the study period. The total WY and SE increased by 30.29% and 98.69%, respectively, between 1972 and 2017. Analysis of the projections for the next three decades (2017-2047) suggested an increase in WY and SE by 4.8% and 93.11%, respectively. Furthermore, results revealed that WY and SE are strongly influenced by landscape composition, and metrics such as percentage of landscape (PLAND), mean patch size (MPS), and large patch index (LPI) of farmland and plantations were found to be key factors affecting HESs degradation in the Beressa watershed. PLAND (VIP = 1.34; w = 0.55; and VIP = 1.32; w = 0.56) and MPS (VIP = 1.32; w = 0.50 and VIP = 1.31; w = 0.56)) of farmland cover contributed most to the changes in WY and SE, respectively. Similarly, PLAND (VIP = 1.33; w = 0.54 and VIP = 1.28; w = 0.52), LPI (VIP = 1.27; w = 0.52 and VIP = 1.30; w = 0.54) and MPS (VIP = 1.29; w = 0.52) of plantation cover also contributed more to the change in WY and SE. Besides that, of anthropogenic factors, compositions of natural vegetation and grassland cover were found to heavily influence HESs in the watershed studied. The findings of the study suggest that soil and water conservation interventions are vital to minimize and control water-related problems and enhance ESs.

Keywords: Blue Nile Basin; Hydrological ecosystem services; InVEST model; Landscape change; PLSR model.

MeSH terms

Conservation of Natural Resources*
Ecosystem*
Ethiopia
Humans
Hydrology
Soil

Substances

Soil