Mapping spatial requirements of ecological processes to aid in the implementation of corridors

Thesis (MSc)--Stellenbosch University, 2015.

ENGLISH ABSTRACT: The ultimate goal of conservation planning is to ensure persistence of biodiversity. Biodiversity patterns and ecological processes are important aspects in conserving biodiversity. Although most researchers in conservation planning have focused on targeting biodiversity patterns, ecological and evolutionary processes can ensure persistence of biodiversity if incorporated into conservation planning. Ecological processes are the main drivers or sustainers of biodiversity. The aim of this research was to identify and map the spatial components of ecological processes in a portion of the Kavango Zambezi Transfrontier Conservation Area to aid in the implementation of biota movement corridors. Different methods have been used to identify suitable corridors but not much has been done on defining and mapping ecological processes that will ensure that the corridors maintain and generate biodiversity. A thorough literature survey was done to make a list of ecological processes that are important in maintaining the biodiversity in the area. Spatial components of ecological processes were mapped as surface elements aligned along linear environmental interfaces or gradients. The last part of the research was to suggest suitable movement corridors based on ecological processes. The results include five spatial components: riverine corridors, areas of high carbon sequestration, edaphic interfaces, upland-lowland interfaces and ecotones. Riverine corridors were mapped using a 1000 m buffer on either side of low lying rivers and 500 m buffer around rivers in the uplands. A map showing the carbon sequestration potential of vegetation in the study area was made using Moderate-Resolution Image Spectroradiometer (MODIS) derived NDVI data and the National Level Carbon Stock dataset done by the Woods Hole Research Center (WHRC) Pantropical. Edaphic interfaces were idenfied using by a 250 m buffer around contrasting soil types. Upland-lowland interfaces identified by a 250 m buffer along upland and lowland habitats. Classification of Landsat 8 was used to identify ecotones in the study area. The results of the spatial components were then compared with the habitat transformation map which shows populated areas.

AFRIKAANSE OPSOMMING: Die uiteindelike doel van bewaringsbeplanning is om voortbestaan van biodiversiteit te verseker. Biodiversiteitspatrone en ekologiese prosesse is belangrike aspekte in die bewaring van biodiversiteit. Alhoewel die meeste navorsers in bewaringsbeplanning fokus op teiken biodiversiteitspatrone, kan die voortbestaan van ekologiese en evolusionêre prosesse van biodiversiteit verseker word deur insluiting in bewaringsbeplanning. Ekologiese prosesse is die belangrikste drywers, of onderhouers, van biodiversiteit. Die doel van hierdie navorsing was dus om die ruimtelike komponente van ekologiese prosesse in 'n gedeelte van die Kavango Zambezi oorgrensbewaringsgebied te identifiseer en te karteer om te help met implementering van biota bewegingsdeurlope. Verskillende metodes is al gebruik om gepaste deurlope te identifiseer, maar min navorsing is gedoen oor definisie en kartering van ekologiese prosesse om te verseker dat die deurlope biodiversiteit sal onderhou en genereer. 'n Deeglike literatuurstudie is gedoen om 'n lys op te stel van ekologiese prosesse wat belangrik is in die handhawing van biodiversiteit in die gebied. Ruimtelike komponente van ekologiese prosesse is gekarteer as oppervlak elemente gebonde aan lineêre omgewingskoppelvlakke of gradiënte. Die laaste deel van die navorsing was om geskikte bewegingsdeurlope, gebaseer op ekologiese prosesse, voor te stel. Die resultate sluit vyf ruimtelike komponente in: rivierdeurlope, gebiede van hoë koolstofsekwestrasie, edafiese koppelvlakke, hoogland-Laeveld koppelvlakke en grensekotone. Rivierdeurlope is gekarteer met behulp van 'n 1000 meter buffer aan weerskante van laagliggende riviere en 500 meter buffer rondom riviere in die hooglande. ‘n Kaart wat die koolstofsekwestrasiepotensiaal van plantegroei in die studie area toon is gemaak met behulp van Moderate-Resolution Image Spectroradiometer (MODIS) afgeleide NDVI data en ʼn koolstofvoorraaddatastel (National Level Carbon Stock dataset) voorsien deur die Woods Hole Research Center (WHRC). Pantropiese edafiese koppelvlakke is geïdentifiseer met behulp van 'n 250 meter buffer rondom kontrasterende grondtipes. Hoogland-Laeveld koppelvlakke is geïdentifiseer deur 'n 250 meter buffer langs die berg en laagland habitatte. Klassifikasie van Landsat 8 data is gebruik om ekotone in die studie area te identifiseer. Die resultate van die ruimtelike komponente is vergelyk met die habitattransformasiekaart wat bevolkte gebiede toon.