SALLnet: South African Limpopo Landscape Network

 

SALLnet is one out of nine collaborative projects of the new German–South African research collaboration on global change under the SPACES2 programme, funded by BMBF.

Sallnet
Foto: WG Prof. Linstädter

SALLnet Mission

Enhancing the food security, multi-functionality and resilience of South African Limpopo landscapes under global change, through:

  • Groundwork on testing innovative management practices for arable lands, rangelands and tree orchards, and characterizing farming systems
  • Developing and testing of new approaches and tools for modelling vegetation, food and forage crops, tree crops and farm type dynamics and upscaling field research results in time and space
  • Developing integrative tools and modelling platforms for interactive scenario analysis and joint learning with stakeholders on sustainable land use options
Sallnet
Foto: WG Prof. Linstädter
Sallnet
Bild: WG Prof. Linstädter
Enhancing Landscapes' Multifunctionality
Sallnet
Bild: WG Prof. Linstädter
Enhancing Landscapes' Multifunctionality
Impressions
Foto: WG Prof. Linstädter
Impressions
Impressions
Foto: WG Prof. Linstädter
Impressions

 

Our Role within SALLnet

Workpackage 2: Rangelands & Agroforestry

 

Abstract

Aims: We focus on the ecology and on adaptive management options of Limpopo’s multifunctional landscapes, in particular on rangelands and agroforestry systems. Our ultimate goal is to help farmers achieve resilience in their livelihoods, and to cope better with future climatic conditions.

Approach: To generate results on spatial and temporal scales relevant for decision-making, we combine (a) experiments with (b) field observations, and (c) synergetic analysis.

(a) Experiments: At the heart of our activities is our field experiment DroughtAct, located on the Experimental Farm of the University of Limpopo (see map). This experiment has been set up to evaluate land-use options under (post-)drought conditions. By combining grazing and drought treatments, we address two main research questions: (1) What determines rangelands’ stability (buffering capacity) in face of drought? (2) What are suitable management interventions to avoid degradation (shifts to undesirable states)? After four years of grazing and drought treatments, we will implement a bush encroachment add-on. To this end, nutrient addition and tree seeding treatments will be added.

(b) Field observations: To assess climate change effects on multiple ecosystem services provided by rangelands and agroforestry systems, we will concentrate on SALLnet's 15 target villages along the steep gradient of climatic aridity in Limpopo. Plots will be established in villages’ rangelands and homegardens. Soil- and vegetation mediated ecosystem services will mainly be assessed via a Rapid Ecosystem Functioning Assessment (REFA) while ecosystem services provided by higher trophic levels will mainly be evaluated with a functional trait approach.

(c) Synergies and Upscaling: Field data from the 15 target villages will be used for an integrated assessment of ecosystem services delivered by Limpopo’s multifunctional landscapes. We aim at addressing interactions (synergies and trade-offs) of multiple ecosystem services within and across land-use types, and under future climate conditions. In a first step, ecosystem service bundles will be identified and trade-offs will be quantified. We will then explore direct and indirect effects of environmental conditions (including changing climate and land-use) on ecosystem multifunctionality.

There are options to participate as a student volunteer or for MSc/BSc level theses. Applications should be sent to Anja Linstädter.

PI

Prof. Dr Anja Linstädter

Persons involved

Designated PostDoc: Kai Behn
PhD student: Vincent Mokoka

Runtime

08/2018 - 07/2021

Funding

SPACES2 Call of the Federal Ministry of Education and Research (BMBF)

Cooperation

Germany
Prof Dr Johannes Isselstein, Grassland Science, Department of Crop Sciences, Georg-August-Universität, Göttingen
Dr Simon Scheiter, BiK-F, Senckenberg Natural History Museum and Research Institute, Frankfurt am Main
Prof Dr Catrin Westphal, Agroecology, Department of Crop Science, Georg-August-Universität, Göttingen

South Africa
Prof Dr Kingsley Ayisi, Risk and Vulnerability Assessment Centre, University of Limpopo
Louis Eloff, Experimental Farm Syferkuil, School of Science and Agriculture, University of Limpopo
Prof Dr Barend Erasmus, School of Animal, Plant and Environmental Science, University of the Witwatersrand
Prof Dr Stefan Foord, Department of Zoology, University of Venda
Dr Frances Siebert, Unit for Environmental Sciences and Management, North West University South Africa
Prof Dr Wayne Twine, School of Animal, Plant and Environmental Science, University of the Witwatersrand

Publications

Pfeiffer, M., Langan, L., Linstädter, A., Martens, C., Gaillard, C., Ruppert, J., Higgins, S., Mudongo, E. and Scheiter, S. (2019). Grazing and aridity reduce perennial grass abundance in semi-arid rangelands – Insights from a trait-based dynamic vegetation model. Ecological Modelling, 395, pp. 11-22. Available at: URL.

 

 

Overview

 

Land-use types studied in SALLnet
Quelle: Sallnet
Land-use types studied in SALLnet: 1. Orchards, 2. Agricultural Fields, 3. Rangelands & Agroforestry Systems. Associated cross-cutting topics (4-6) link individual assessments in these land-use types.
Land-use types studied in SALLnet
Quelle: Sallnet
Land-use types studied in SALLnet: 1. Orchards, 2. Agricultural Fields, 3. Rangelands & Agroforestry Systems. Associated cross-cutting topics (4-6) link individual assessments in these land-use types.
Impressions
Foto: WG Prof. Linstädter
Impressions
Impressions
Foto: WG Prof. Linstädter
Impressions
German-South African research team
Foto: WG Prof. Linstädter
German-South African research team
German-South African research team
Foto: WG Prof. Linstädter
German-South African research team

 

Rangeland Management in Face of Drought - the DroughtAct Experiment

 

The DroughtAct experiment addresses two main research questions:

(1) What determines rangelands’ stability in the face of drought?

(2) What are suitable management interventions to avoid degradation?

DroughtAct t is located at the experimental farm of the University of Limpopo, South Africa (Figure 1). It combines rainfall and grazing treatments (Figures 2 & 3), simulating realistic climate conditions under future climate change regimes in conjunction with potential management interventions. The experiment is part of the International Drought Experiment (IDE), initiated by Drought-Net, a global network to assess terrestrial ecosystem sensitivity to drought.

Details on the experiment

  • We simulate a severe drought in combination with different resting schemes
  • The experimental treatments are replicated four times (Figure 1)

A pilot study for a network experiment on joint grazing and drought effects
The DroughtAct experiment is also a pilot study for an extension of the International Drought Experiment (IDE). With this grazing add-on, it will be possible to study combined grazing and drought effects over a broad range of terrestrial ecosystems to better understand their potentially interactive effects on ecosystems functioning and ecosystem service provision.

The grazing add-on also allows transferring the IDE approach (that requires undisturbed sites) to ecosystems which are subject to herbivory by wild or domestic herbivores. The sampling procedures of DroughtAct are fully compatible with the core IDE protocol. You can download our sampling protocol with the grazing add-on to Drought-Net [here].

If you are interested in the DroughtAct approach, contact Anja: linstaedter[at]uni-potsdam.de

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Foto: WG Prof. Linstädter

 

Figure 2: Temporal grazing exclosure-cage with soil moisture probe. Cages allow for accurate estimation of aboveground net primary production (ANPP) under grazing conditions. The scattered soil moisture probes (white cap in foreground) allow for mid- to high-resolution monitoring of temporal and spatial patterns of plant available water.

 

 

 

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Foto: WG Prof. Linstädter
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Foto: WG Prof. Linstädter

 

 

Figure 3: Rainout shelters simulating a centennial-scale drought (intercepting 66% of rainfall). Each shelter is 6 m x 6m in size. Trenches filled with impermeable membranes avoid below surface water run-on, hence, the typical rooting-zone of grasses is detached from the surrounding soil-moisture.

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Foto: WG Prof. Linstädter

 

 

Impressions

Impressions
Foto: WG Prof. Linstädter
Impressions
Foto: WG Prof. Linstädter
Overview on experimental layout at Syferkuil
Quelle: WG Prof. Linstädter
Figure 1: Overview on experimental layout at Syferkuil. (A) Location of the Syferkuil Farm in the vicinity of Mangkweng. (B) Layout of the selected camp at the farm. (C) detailed layout of the 4 replication blocks, each hosting 9 plots.
Overview on experimental layout at Syferkuil
Quelle: WG Prof. Linstädter
Figure 1: Overview on experimental layout at Syferkuil. (A) Location of the Syferkuil Farm in the vicinity of Mangkweng. (B) Layout of the selected camp at the farm. (C) detailed layout of the 4 replication blocks, each hosting 9 plots.