Grassland loss in Tanzania: Causes, consequences and control
List of Authors
  • Emmanuel F. Nzunda

Keyword
  • cultivation, bush encroachment, population growth, management challenges, land use conflicts, soil eroding floods

Abstract
  • Grasslands are an important component of rangelands. The work presented in this paper is based on spatial statistical analysis of grassland change between 1995 and 2010 using land use and land cover maps covering the whole of mainland Tanzania and GIS. Further arguments for discussion in the paper are sourced from literature review. Results show that grasslands are lost at an alarming rate of almost 1 million hectares annually. Between 1995 and 2010 Tanzania lost more than 14 million hectares of grassland. Main direct causes of grassland loss are conversion to cultivation and to forest cover, almost at an equal rate of more than 6 million hectares over the 15 year period (about 400,000 ha annually). Bush encroachment is also an important direct driver of grassland loss. Indirect causes of grassland loss include population growth, economic growth, challenges in grassland governance and management and globalization. Consequences of grassland loss include reduced areas for grazing, increased soil erosion, floods, increased land use conflicts and their repercussions including loss of property and life. Control measures include those addressing the direct and indirect drivers of change. However, most of the control measures are ineffective and hence the observed trend of grassland loss. The paper concludes by suggesting some topics for further research into ways to improve the effectiveness of the control measures against grassland loss in terms of potential and possibility of more agricultural intensification, improvements of markets and profits to cultivators, nature of grassland loss to forest cover, ways to apply existing extensive research on bush encroachment and, the role of formal and informal institutions that control grassland loss.

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