s:936:"TI Regreening Africa: A bottom-up transformation of degraded lands AU Koech, G. AU Winowiecki, L.A. AU Westermann, O. AU Bourne, M. AU Wamawungo, D. AU VĂ¥gen, T-G. AU Ojee, S. AU Chomba, S. AU Carsan, S. AB It is estimated that 20% of global land is either degraded or undergoing degradation, leading to an annual loss of 12 million hectares of productive land (UNCCD 2017). In Africa, some 715 million ha are degraded, including 65% of all arable land, 30% of all grazing land and 20% of all forests. This is due to increasing populations, poor land management, institutional challenges and climate change (Gnacadja and Wiese 2016). The benefits of taking action against land degradation outweigh the costs by up to seven times, implying that inaction will cost countries US$490 billion per year, while action to reverse land degradation could generate benefits worth up to US$1.4 trillion (ELD Initiative 2015) ";