human impacts
Today, a range of human activity seriously threatens the unique vegetation of the Cape Floristic Region. Agricultural expansion has reduced lowland habitats such as the Sandplain fynbos and Coast renosterveld by 83 percent and 48 percent of their original extent, respectively. Much of what remains exists in isolated fragments in a matrix of chemically treated agriculture. Agricultural development is encroaching on natural areas even in the mountains, where impoverished soils previously limited agriculture; farming of rooibos tea, (Aspalathus linearis), honeybush tea (Cyclopia spp.), cut flowers (mainly Proteaceae), and, of course, vineyards pose a significant threat to the remaining vegetation.In addition, urban encroachment and development, particularly near the city of Cape Town, is a threat to natural habitats. Although urban and industrial areas currently occupy less than 1 percent of the land area in the hotspot, population is growing rapidly; Cape Town's population is expected to double by the year 2025. However, the greatest threat to this hotspot is the effect of invasive alien plant species. For decades, trees and shrubs from other Mediterranean-type climates such as southern Australia, the Mediterranean Basin, and California have been introduced into the region to supplement the few tree species native to the Cape. These alien species have invaded about 70 percent of mountain and lowland fynbos, altering natural fire frequencies, diminishing mountain-derived water production, and ultimately eliminating native species. Overall, some 33 percent of the Cape Floristic Region has been transformed by agriculture, urbanization and dense stands of alien invasive plants. However, only about 15,700 km², or 20 percent, is in pristine condition, being free of invasive alien plants and subject to appropriate fire regimes.
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© Conservation International, photo by Tessa Mildenhall
The expansion of agricultural land for vineyards is one of the biggest causes of habitat destruction in the Cape Floristic Region.
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