Changes in ecosystem service values strongly influenced by human activities in contrasting agro-ecological environments

Ecological Processes

Mitsuru Tsubo¹  Atsushi Tsunekawa¹  Ayele Almaw Fenta¹  Mulatu Liyew Berihun²  Nigussie Haregeweyn³ 

[1] Arid Land Research Center, Tottori University, 1390 Hamasaka, 680-0001, Tottori, Japan;Faculty of Civil and Water Resources Engineering, Bahir Dar Institute of Technology, Bahir Dar University, P.O. Box 26, Bahir Dar, Ethiopia;Arid Land Research Center, Tottori University, 1390 Hamasaka, 680-0001, Tottori, Japan;International Platform for Dryland Research and Education, Tottori University, 1390 Hamasaka, 680-0001, Tottori, Japan;

关键词: Drought prone;    Agro-ecologies;    Land use/land cover;    Acacia decurrens;    Plantations;    Ecosystem services;    Farming practices;    Upper Blue Nile basin;   

DOI  :  10.1186/s13717-021-00325-1

来源: Springer

【 摘 要 】

BackgroundEvaluating the impacts of land-use/land-cover (LULC) changes on ecosystem service values (ESVs) is essential for sustainable use and management of ecosystems. In this study, we evaluated the impact of human activity driven LULC changes on ESVs over the period 1982–2016/17 in contrasting agro-ecological environments: Guder (highland), Aba Gerima (midland), and Debatie (lowland) watersheds of the Upper Blue Nile basin, Ethiopia.ResultsDuring the study period, the continuous expansion of cultivated land at the expense of natural vegetation (bushland, forest, and grazing land) severely reduced the total ESV by about US$ 58 thousand (35%) in Aba Gerima and US$ 31 thousand (29%) in Debatie watersheds. In contrast, the unprecedented expansion of plantations, mainly through the planting of Acacia decurrens, led, from 2006, to a ESV rebound by about US$ 71 thousand (54%) in Guder watershed, after it had decreased by about US$ 61 thousand (32%) between 1982 and 2006. The reduction in natural forest area was the major contributor to the loss of total ESV in the study watersheds, ranging from US$ 31 thousand (63%) in Debatie to US$ 96.9 thousand (70%) in Guder between 1982 and 2016/17. On an area-specific basis, LULC changes reduced the average ESV from US$ 560 ha−1 year−1 (1982) in Guder to US$ 306 ha−1 year−1 (2017) in Debatie watersheds. Specific ESVs such as provisioning (mainly as food production) and regulating services (mainly as erosion control and climate regulation) accounted for most of the total ESVs estimated for the study watersheds.ConclusionsIn most cases, the total and specific ESVs of the watersheds were negatively associated with the population growth, which in turn was positively associated with the expansion of cultivated land over the study period. In Guder, however, ESVs were positively associated with population growth, especially after 2012. This is mainly due to the expansion of Acacia decurrens plantations. Our results suggest, therefore, that future policy measures and directions should focus on improving vegetation cover through planting multipurpose trees such as Acacia decurrens to prevent future loss of ESV in the midland and lowland regions of the Upper Blue Nile basin and beyond. However, caution must be taken during plantation of invasive species as they may have undesirable consequences.

【 授权许可】

CC BY