Invasive alien plants have a negative impact on ecosystem goods and services derived from ecosystems. Consequently, the aggressive spread of invasive alien plants (IAPs) in the river catchments of South Africa is a major threat to, inter alia, water security. The Olifants River catchment is one such a catchment that is under pressure because of the high demand for water from mainly industrial sources and unsustainable land-use, which includes IAPs. This study considered the cost-effectiveness of clearing IAPs and compared these with the cost of a recently constructed dam.

The greater the benefit derived from using a piece of land for any particular purpose the higher the price the prospective user is willing to pay.  The demand for land is thus a reflection of the utility derived from its use by current or potential users.  The ability to compete for sites depends on whether they have the means to benefit from accessibility and complementarity within the urban framework. Conventional theory states that productivity determines urban rent, which is the highest at the place of maximum accessibility, i.e. the central business district (CBD).

This study explores the influence of incidence of poverty and plot-level perception of soil degradation, on soil conservation behaviour of small subsistence farmers in the central highlands of Ethiopia. The study results confirm that poverty in assets significantly reduces the probability of soil-conservation efforts as measured by use of stone/soil bund structures in the highlands of Ethiopia.