In the context of the TDA/SAP process, environmental impacts are the effects of a transboundary problem on the integrity of an ecosystem whereas socio-economic impacts are a change in the welfare of people attributable to the transboundary problem or its environmental impacts.

For example, eutrophication due to nutrient over-enrichment may result in high concentrations of nitrates of phosphates in a particular water body but the question is: what are the impacts or consequences of this?

An environmental impact might be a reduced fish population. This could result in a loss of income and/or a food a source for the riparian population. These are indirect socio-economic impacts of the problem. However, there may also be direct socio-economic impacts, for example the impact on health from polluted drinking water. This is shown in the diagram below: