We used the process-oriented niche model CLIMEX to estimate the potential global distribution of serrated tussock under projected future climates. Serrated tussock is a drought-tolerant, wind- and human-dispersed grass of South American origin that has invaded pastures in Australia, Europe, New Zealand, and South Africa. The likely effect of climate change on its potential global distribution was assessed by applying six climate-change scenarios to a previously developed model.
The aim of this paper is to shed new light on urban common property systems. We deal with urban commons in relation to urban green-space management, referring to them as urban green commons. Applying a property-rights analytic perspective, we synthesize information on urban green commons from three case-study regions in Sweden, Germany, and South Africa, and elaborate on their role for biodiversity conservation in urban settings, with a focus on business sites. Cases cover both formally established types of urban green commons and bottom-up emerged community-managed habitats.
Natural vegetation and crop-greening patterns in semi-arid savannas are commonly monitored using normalized difference vegetation index (NDVI) values from low spatial resolution sensors such as the Advanced Very High Resolution Radiometer (AVHRR) (1 km, 4 km) and Moderate Resolution Imaging Spectroradiometer (MODIS) (250 m, 500 m). However, because semi-arid savannas characteristically have scattered tree cover, the NDVI values at low spatial resolution suffer from the effect of aggregation of near-infrared and red energy from adjacent vegetated and non-vegetated cover types.
South Africa has undergone enormous economic, social and political change since its democratization process began in 1994. This policy note provides a preview of key findings of the OECD's agricultural policy review for South Africa.Over the last 15 years, with the abolition of apartheid, South Africa has experienced fundamental change led by dramatic policy reforms aimed at creating a more open and market-oriented economy.
Successful land claims on protected areas by previously disenfranchised communities often result in co-management agreements between claimant communities and state conservation agencies. South Africa, in particular, has pursued co-management as the desired outcome of land claims on its protected areas. We review four cases of co-management on protected areas in South Africa, and reflect on the appropriateness of the pursuit of co-management as the preferred outcome of land claims.
A good indicator of successful farm redistribution cases has to be the continuation of viableproductivity rates in their post transfer periods. Continued productivity benefits all thestakeholders that are involved in the process. Unfortunately negative productivity levels havebeen reported in numerous South African land redistribution transfers in recent years.
The advent of grid electrification in the Sandveld region of South Africa in the 1980s increased the utilisation of groundwater resources for commercial irrigation purposes. In the wake of the consequent increased pressure on the resource, it behooves landowners to use water more productively and responsibly. This paper calculated the marginal product value (MPV) of irrigation water for potatoes and vine production in this region to assess and to allow the comparison of the productivity of irrigation water with other commodities and regions.
To establish the significance of Henry Bernstein's theoretical work on the dynamics of agrarian class struggles in Africa, this paper discusses two important political debates in which he has been both observer and participant, and that have oriented much of the subsequent Marxist work done in Africa on agrarian change. The first was the heated discussion begun over 40âyears ago around Nyerere's âAfrican socialismâ and the failures of the ujamaa policy of villagization. The second is the still unsettled debate around programmes of redistributive land reform in South Africa.
The acceleration of soil erosion by water in most regions of the world in response to the anthropogenic modification of landscapes is a serious threat to natural ecosystem functionalities because of the loss of invaluable constituents such as soil particles and organic carbon (OC). While soil OC erosion is likely to be a major component of the global C cycle, water erosion-induced CO₂ emissions remain uncertain. In this study, our main objective was to compare the release of CO₂ from eroded topsoils and from the sediments exported by diffuse erosion during an entire rainy season.
The Okavango catchment in southern Africa is subject to environmental as well as socio‐economic transformation processes such as population growth and climate change. The degradation of soil and vegetation by deforestation and overgrazing is one of the downsides of this development, reducing the capacity of the land to provide ecosystem functions and services. In this study, climate simulations are brought together with secondary socioeconomic, pedologic and remote‐sensing data in a GIS‐based assessment of the factors commonly associated with land degradation risk.