Vulnerability

The degree to which a system is susceptible to, or unable to cope with, adverse effects of environmental change defines its vulnerability (UNEP 2005). The ultimate goal of most individuals is to move towards a state of security and minimise vulnerability.

Individuals or communities can be vulnerable to direct impacts, such as a flood or fire, and indirectly vulnerable in situations such as groundwater levels declining due to long-term decreases in rainfall that result from climate change. However, the most significant factor in vulnerability is its compound nature, where individuals, groups and communities are subject to more than threat at the same time.

The United Nations Environment Programme (UNEP) conducted a study to determine the vulnerability of water resources to environmental change in Africa.  The study developed parameters and related indicators which were grouped into physiographic (natural), socio-economic (anthropogenic), and management clusters (see table below).

Parameters and vulnerability indicators assessing the vulnerability of water resources to environmental change.

Cluster		Parameter *	Vulnerability Indicator*
Physiography	Climate	Rainfall Evapotranspiration	· Aridity	Water Scarcity
	Ecosystems	Water dependency Land cover Land use	· Water availability · Desertification · Storage and supply infrastructure
	Hydrology	Stream flow
		Storage Quality
	Hydrogeology
		Yield Recharge
Socio- Economy	Demography	Population size and distribution HIV-AIDS/ water-related diseases Water demand Water supply Value of water	Population density and growth Poverty Access to water Water use Conflicts
	Economy
Management	Legislation	Policies Acts Regulations Guidelines	Sector reform Implementation and adaptive capacity
	Institutional	Adherence to IWRM principles · Human resources
	Knowledge	Literature/reports	Data availability, gaps and quality

Vulnerability of Southern Africa's Water Resources and Environmental Change

In southern African countries, economies are heavily dependent on agriculture (often subsistence) and patoralism, the success of which is determined by climatic conditions. Because of their relatively low development status these countries are therefore vulnerable to unexpected changes in climatic variables (UNEP 2005).

The following Vulnerability Indicators are used to determine southern Africa's vulnerability in relation to water resources and environmental change (UNEP 2005):

Aridity and Water Availability: Aridity and vulnerability are linked, with the highest incidence being in the western and southern parts of the region. An FAO projection (1995) to 2025 predicts that the water availability per person will decrease due to increased demand and a reduction in accessibility.

Water Demand and Water Use: Population growth, urbanisation, industrial and agricultural development and improved living conditions all indicate that water demand and use will increase in the future resulting in less available water.

Population Density and Growth: The population growth rates in cities and major towns are higher than the regional average.

Water-Related Conflicts: The Limpopo River is cited as being an area for potential conflict in the future as African countries are likely to exceed their 'economically usable land-based water resources before 2025 (Ashton 2002)'.

Sector Reform: the progress so far towards water sector reforms in this region is a positive trend towards creating enabling environments in order to mitigate against environmental change.

Limpopo Basin Strategic Plan for Reducing Vulnerability to Floods and Droughts

In 2007, UN-Habitat/UNEP and the Limpopo Basin riparian countries published the 'Limpopo Basin Strategic Plan for Reducing Vulnerability to Floods and Droughts'. The working document assesses the current state of vulnerability in the basin, with relation to its environment and policies, and proposes activities, such as an early warning system, that could reduce vulnerability.