Aquatic areas of ecological importance as inputs into surface water resource protection areas in Zambia

Abstract

1. Although the network of national parks in Zambia offers a degree of protection for freshwater diversity, the protection status of numerous systems outside of these parks requires further action. The biodiversity associated with its freshwater systems, both lotic and lentic, is unique, covering a climatic gradient from tropical to subtropical across the Zambezi and Congo basins. Recent Zambian legislation allows for the delineation of water resource protection areas (WRPAs), with one of the criteria being that they include aquatic areas of ecological importance (AEIs).2. In this study, a systematic conservation planning approach was used to identify aquatic AEIs objectively. Importantly, the approach included a rigorous and iterative stakeholder engagement and review process.3. The conservation planning software MARXAN was chosen because of its ability to integrate upstream-downstream connectivity. In total, 5,671 planning units (sub-catchments with an average area of approx. 14,000 ha) were populated with 77 biodiversity features: data were drawn from a wide range of sources, and included fishes, semi-aquatic mammals, molluscs, amphibians, and ecotonal physiographic features, such as waterfalls. Sub-catchments were preferentially chosen using a combination of area-and distance-weighted boundary costs.4. The final solution highlights critical clusters in each of the major freshwater ecoregions in Zambia, with all conservation targets being met. Results show that although the existing protected area network also coincides with identified aquatic AEIs, approximately 80% of all aquatic AEIs fall outside of formally protected areas.5. The outcomes of this process serve as one of three prioritization layers (the other two being water provision and sensitivity to human impacts) that are integrated in a larger study to select and prioritize WRPAs.

Identifying priority areas for surface water protection in data scarce regions: An integrated spatial analysis for Zambia

“…These include parts of the upper Zambezi catchment, the Zambezi floodplain, Kafue Flats, parts of the Luangwa catchment, and Lake Tanganyika. The spatial distribution of identified high-ranking aquatic AEIs generally corresponds well with major wetland systems and important bird areas and also reflects important habitats for large mammals such as lechwe and other large semi-aquatic mammals (Rivers-Moore et al, 2021). The final solution shows a reasonable congruence with an earlier study by Pence (2012), bearing in mind that this study used the whole of the Zambezi Basin rather than Zambia as its planning domain.…”

“…Of the total area of national parks in Zambia, 70.6% coincide with the selected aquatic AEIs of the best solution; however, almost 80% of the identified aquatic AEIs still fall outside this most restrictive type of protection (Rivers-Moore et al, 2021). Thus, there remains considerable scope for expanding the conservation area network to protect the remaining 80% of identified aquatic AEIs that are not protected at present by national parks.…”

“…First, a prioritization using systematic conservation planning software was conducted to classify all sub-catchments according to their biodiversity value. A detailed report is available as a companion paper which fully describes this study, its methods and results (Rivers-Moore et al, 2021). Second, a separate study was conducted to identify free-flowing rivers in Zambia (Grill et al, 2017).…”

“…Results of aquatic areas of ecological importance (AEIs) assessment conducted by Rivers-Moore et al (2021), standardized into 10 ranks using equal quantiles. (b) Results of freeflowing river (FFR) assessment conducted by Grill et al (2017), ranked into 10 classes based on FFR status and river length (all length intervals in the key include the lower boundary and exclude the upper boundary).…”