Rehabilitation of grasslands after eradication of alien invasive trees

“Emva kwe dywabusi”

A Water Research Commission Project (K5/2400/4)

Clearing of the IAPs on their own is not sufficient motivation to proceed with the national Working for Water (WfW) programme, and there needs to be consideration of the sustainability of the landscape when the activities of WfW are completed. In order to ensure sustainability of landscape processes for human benefit, it is essential to build stronger links between the control of undesirable woody plants and the derived benefits to humans occupying the catchment. In order to strengthen this linkage, empirical evidence of the water use of every component of the landscape needs to be collected. The landscape units or land cover types that are encountered in the mesic regions of South Africa are diverse, comprising inter alia areas of irrigation agriculture, dryland cultivation, residential, extensive rangeland and forests. Superimposed on this are two different land tenure systems, namely freehold farms and communal or leasehold areas, each with diametrically opposed approaches to landscape management. There is a need to improve our understanding of how to balance water use and carbon capture between different land cover types and land tenure systems as both these cycles are important to people and their livelihoods. Two possible approaches for assessing the relative efficiency of the landscape for secondary production are the concepts of livestock water productivity (LWP) and water use productivity (WUP). In the rural landscapes of the south eastern parts of South Africa (e.g. former Transkei and Kwa-Zulu Natal), land use is dominated by a complex arrangement of dwellings, livestock grazing, dryland cultivation and forestation, all within a communal land tenure system. The capture of carbon by the landscape is the primary driver of livestock and food production in this human-dominated social-ecological system (SES) and understanding the total economic value and water use efficiency (WUE) of these processes requires an empirical assessment of the water cycle.

Thus, the aims of this project are:

  1. To parameterize, evaluate and modify suitable models for ET, LWP and NPP estimates for IAPs and grasslands.
  2. To explore and compare ET, LWP and NPP in three catchments with contrasting land tenure systems, comprising diverse biomass and condition states for grassland and IAPs.
  3. To apply the selected models for predicting ET, LWP and NPP to these catchments.
  4. To examine the possibility of using a Reward for Ecosystem Services (RES) system in rural rangelands as a possible solution to degradation and water issues (quantity and quality).

The five year project is running from April 2014 to March 2019.

Project Team

Project leader:

Dr. Sukhmani Mantel, IWR, Rhodes University


Dr. Anthony Palmer (Palmer (Agricultural Research Council), Ms Zahn Munch (University of Stellenbosch), Dr Lesley Gibson (Cape Nature), Dr Chris de Wet (IWR, Rhodes University)

Post-graduate students:

Mr. Onalenna Gwate (PhD candidate), Ms Perpetua Okoye (MSc candidate), Ms Bukho Gusha (PhD candidate)


Mr Robert Scholtz (Joe Gqabi District Municipality), Mr Adam Perry (previously of Fort Hare’s Institute of Social and Economic Research)

Project Deliverables

Deliverable 1: Inception report

Deliverable 2: Report on the outcomes of the first workshop

Deliverable 3: First year progress report

Deliverable 4: Models for ET estimation

Deliverable 5: Report on the outcomes of the second workshop

Deliverable 6: Second year progress report

Deliverable 7: Comparison of ET for 2 land use catchments

Deliverable 8: Report on the outcomes of third workshop

Deliverable 9: Third year progress report

Deliverable 10: Report on evaluation of models and their application

Deliverable 11: Report on the outcomes of final workshop

Deliverable 12: Draft final report with final workshop report

Last Modified: Thu, 17 Sep 2015 11:15:23 SAST