Hostname: page-component-74656f9884-qr5l4 Total loading time: 0 Render date: 2026-11-05T07:54:30.519Z Has data issue: false hasContentIssue false

Thresholds of change in a multi-use conservation landscape of South Africa: historical land-cover, future transformation and consequences for environmental decision-making

Published online by Cambridge University Press:  20 May 2016

KAERA L. COETZER-HANACK*
Affiliation:
Global Change and Sustainability Research Institute (GCSRI), University of the Witwatersrand, WITS, 2050, Johannesburg, South Africa School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, WITS, 2050, Johannesburg, South Africa
E.T.F. WITKOWSKI
Affiliation:
School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, WITS, 2050, Johannesburg, South Africa
BAREND F.N. ERASMUS
Affiliation:
Global Change and Sustainability Research Institute (GCSRI), University of the Witwatersrand, WITS, 2050, Johannesburg, South Africa
*
*Correspondence: K.L. Coetzer-Hanack klcoetzer@gmail.com
Rights & Permissions [Opens in a new window]

Summary

As multi-use conservation landscapes, biosphere reserves (BRs) exemplify the landscape mosaic approach to environmental decision-making. In this study, time-series remotely-sensed data (1993–2006–2012) were used to monitor vegetation transformation in the Kruger to Canyons Biosphere Reserve (K2C) of South Africa, updating previous land-cover research. We identified changes in spatial extent, rate and intensity of land-cover change and extrapolated observed trends to 2018. The increased rate of change in the recent observation period (2.3 vs. 5.7%) was driven by more intensive gains in impacted vegetation and settlement since 2006 (>210 km2 and >120 km2), with resultant transformation of intact habitat undermining regional connectivity. By 2012, intact vegetation had suffered losses of 6.3% (>350 km2) since 2006 and >14% (>750 km2) since 1993. A further 9.5% loss of intact habitat may represent a critical threshold, establishing K2C above the 50% threshold of landscape transformation, whereafter a rapid decline in landscape resilience is likely. Given the BR's spatial zonation, such a loss across the full extent of K2C is unlikely, at least in the short-term (i.e., by 2018). Yet, based on past trends of transformation in the unprotected transition zone, anticipating such losses in the longer term, is not unfounded (i.e., 2024).

Information

Type
Papers
Copyright
Copyright © Foundation for Environmental Conservation 2016 
Figure 0

Figure 1 (a) Regional location of the Kruger to Canyons Biosphere Reserve (K2C) relative to national and provincial boundaries, (b) including land-use, administrative boundaries and main towns, with (c) spatial zonation indicated. Figure legend refers to inset (b).

Figure 1

Figure 2 Change in percentage contribution of priority classes across Kruger to Canyons Biosphere Reserve (K2C) 1993–2012. The dashed lines beyond 2012 indicate a linear extrapolation of change based on the 2006–2012 transition. The values in brackets {} provide the extrapolation based on full 1993–2012 analysis period for comparison.

Figure 2

Table 1 Land-cover transition matrix for priority cover classes (measured as percentage of study area): 1993–2006 and 2006–2012. Percentage values on the diagonal indicate persistence, with those on the vertical and horizontal indicating exchanges between classes in each time interval.

Figure 3

Figure 3 Intensity of change across the Kruger to Canyons Biosphere Reserve (K2C), presented by time intervals, with historical (a, b, c) and future views (d, e, f) indicated. (a) represents the interval intensity from 1993–2012, while (b–f) indicate category intensities of gross losses and gains within cover classes/per specified time interval. The horizontal dashed line indicates the uniform intensity of change that would occur if observed changes were distributed equally over the time interval indicated on each figure, with those above (hatched) showing changes that are relatively fast over that period (‘interval intensity’, [a]) or ‘active’ contributors to change (‘category intensities’, [b–f]). Uniform intensity values are a function of area of change and duration of the interval.

Figure 4

Figure 4 Spatial patterns of gains, losses and persistence in (a) settlement, (c) impacted vegetation and (e) intact vegetation for 2006–2012, with zonation indicated. (b, d and f) indicate changes as a function of zone extent for 1993–2006 and 2006–2012 as a percentage, where C = core, B = buffer and T = transition zones. For display purposes, the y-axis scaling differs between classes, with the maximum percentage value on settlement axis at 16%, impacted vegetation at 35% and intact vegetation at 100%.

Supplementary material: Image

Coetzer-Hanack supplementary material S1

Supplementary Figure

Download Coetzer-Hanack supplementary material S1(Image)
Image 1.3 MB
Supplementary material: Image

Coetzer-Hanack supplementary material S2

Supplementary Figure

Download Coetzer-Hanack supplementary material S2(Image)
Image 100.2 KB
Supplementary material: Image

Coetzer-Hanack supplementary material S3

Supplementary Figure

Download Coetzer-Hanack supplementary material S3(Image)
Image 78.3 MB
Supplementary material: File

Coetzer-Hanack supplementary material S4

Supplementary descriptions

Download Coetzer-Hanack supplementary material S4(File)
File 15.5 KB
Supplementary material: File

Coetzer-Hanack supplementary material S5

Supplementary Table

Download Coetzer-Hanack supplementary material S5(File)
File 18.3 KB