Cape Flats Dune Strandveld (Dune Thicket) Distribution




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Cape Flats Dune Strandveld

(Dune Thicket)



Distribution: Endemic to Cape Town; mainly coastal, altitude 0-80m, but reaching 200m in places

Vegetation & landscape: flat to slightly undulating dune field landscape covered by tall evergreen, hard-leaved shrubland with abundant grasses and annual herbs in gaps. Structurally, strandveld is a tall, evergreen, hard-leaved shrubland with abundant grasses, annual herbs and succulents in the gaps. Examples of prominent shrub species include Euclea racemosa, Metalasia muricata, Olea exasperata, Chrysanthemoides monilifera and Roepera flexuosum. Strandveld has few endemic species compared to fynbos. 100% of this vegetation type occurs within the City and 56% is transformed.

Geology & Soil: tertiary to recent calcareous sand of marine origin. Outcrops of limestone found on the False Bay coast.

Climate: Mean Annual Rainfall 350mm in N to 560mm in S.

Endemic: Lampranthus tenuifolius

Conservation: Endangered: target 24%; 6% conserved.


National Vegetation Type

Historical area in Cape Town (km2)

% in Cape Town

Current area in Cape Town (km2)

Conserved or managed in Cape Town (km2)

National Ecosystem Status*

Cape Flats Dune Strandveld

401

100

180

64

EN

*National vegetation types in bold typeface are confined to Cape Town; CR = Critically Endangered, EN = Endangered, VU = Vulnerable, LC = Least Concern
Cape Flats Sand Fynbos

(Sand Plain Fynbos)



Distribution: Largely ndemic to the City of Cape Town: Cape Flats from Blouberg and Koeberg Hills west of the Tygerberg Hills to Lakeside and Pelican Park in the south near False Bay, from Bellville and Durbanville to Klapmuts and Joostenberg Hill in the east, and to the southwest of the Bottelary Hills to Macassar and Firgrove in the south. Altitude 20–200 m. Nearly 100% of this vegetation type occurs within the City and 85% is transformed.

Vegetation & Landscape Features: Moderately undulating and flat plains, with dense, moderately tall, ericoid shrubland containing scattered emergent tall shrubs. Proteoid and restioid fynbos are dominant, with asteraceous and ericaceous fynbos occurring in drier and wetter areas, respectively.

Geology & Soils: Acid, tertiary, deep, grey regic sands, usually white, often Lamotte form.

Climate: Winter-rainfall regime with precipitation peaking from May to August. MAP 580–980 mm (mean: 575 mm). Mists occur frequently in winter. Mean daily maximum and minimum monthly temperatures 27.1°C and 7.3°C for February and July, respectively. Frost incidence about 3 days per year. This is the wettest and the coolest of the West Coast sand fynbos types.

Endemic Taxa: Low Shrubs: Erica margaritacea, Aspalathus variegata (probably extinct), Athanasia capitata, Cliffortia ericifolia, Erica pyramidalisW, E. turgida, E. verticillata, Leucadendron levisanus, Liparia graminifolia, Serruria aemula, S. foeniculacea, S. furcellata. Succulent Shrub: Lampranthus stenus. Geophytic Herb: Ixia versicolor. Graminoids: Tetraria variabilis, Trianoptiles solitaria.

Conservation: Critically endangered. Target 30%. Less than 1% statutorily conserved as small patches in the Table Mountain National Park as well as some private conservation areas such as Plattekloof 430 and Blaauwberg Hill. This is the most transformed of the sand fynbos types—more than 85% of the area has already been transformed (hence the conservation target remains unattainable) by urban sprawl (Cape Town metropolitan area) and for cultivation. Most remaining patches are small pockets surrounded by urban areas, for example Rondevlei, Kenilworth, Milnerton, 6BKD, Plattekloof, and Rondebosch Common. Most of these patches have been identified as ‘Core Conservation Sites’. They are mismanaged by mowing, fire protection and by alien plant invasion. Mowing eliminates serotinous and taller species, while fire protection results in a few common thicket species (e.g. Carpobrotus edulis, Chrysanthemoides monilifera), replacing the rich fynbos species. Alien woody species include Acacia saligna, A. cyclops and species of Pinus and Eucalyptus. Dumping and spread of alien grasses (both annual and Kikuyu Pennisetum clandestinum) are also a major problem. Alien acacias result in elevated nutrient levels and a conversion to Eragrostis curvula grassland and near-annual fires. Some 94 Red Data sand fynbos plant species occur on the remnants within Cape Town. The endemics include six species listed as extinct in the wild, some of which are being reintroduced from botanical gardens.

National Vegetation Type

Historical area in Cape Town (km2)

% in Cape Town

Current area in Cape Town (km2)

Conserved or managed in Cape Town (km2)

National Ecosystem Status*

Cape Flats Sand Fynbos

547

100

77

5

CR

*National vegetation types in bold typeface are confined to Cape Town; CR = Critically Endangered, EN = Endangered, VU = Vulnerable, LC = Least Concern

Swartland Shale Renosterveld

(West Coast Renosterveld)



Distribution: Western Cape Province: Large, generally continuous areas of the Swartland and the Boland on the West Coast lowlands, from Het Kruis in the north, southwards between the Piketberg and Olifantsrivierberge, widening appreciably in the region around Moorreesburg between Gouda and Hopefield, and encompassing Riebeek-Kasteel, Klipheuwel, Philadelphia, Durbanville, Stellenbosch to the south and Sir Lowry’s Pass Village near Gordon’s Bay. Altitude 50–350 m. 9.8% of this vegetation type occurs within and 90.2% outside the City. Similar transformation rates occur nationally (92%) and inside City borders (91%).

Vegetation & Landscape Features: Moderately undulating plains and valleys supporting low to moderately tall leptophyllous shrubland of varying canopy cover as well as low, open shrubland dominated by renosterbos. Heuweltjies are a very prominent local feature of the environment, forming ‘hummockveld’ near Piketberg and giving the Tygerberg Hills their name. Stunted trees and thicket are often associated with the heuweltjies. Disturbed areas are dominated by Athanasia trifurcata and Otholobium hirtum. Patches of Cynodon dactylon ‘grazing lawns’ also occur in abundance.

Geology & Soils: Clay soils derived from Malmesbury Group shales (specifically the Porterville Formation in the north and east and the Moorreesburg Formation in the west). The soils contain prismacutanic and pedocutanic diagnostic horizons and Glenrosa and Mispah forms are predominant.

Climate: Winter-rainfall regime, with MAP 270–670 mm (mean: 430 mm), peaking from May to August. Mean daily maximum and minimum temperatures 29.6°C and 6.3°C for February and July, respectively. Frost incidence 3 or 4 days per year. Mists are common in winter.

Endemic Taxa: Low Shrubs: Leucadendron verticillatum, Aspalathus acanthophylla, A. horizontalis, A. pinguis subsp. longissima, A. pinguis subsp. occidentalis, A. puberula, A. rectistyla, Cliffortia acockii, Lotononis complanata, Serruria incrassata. Succulent Shrubs: Erepsia ramosa, Ruschia patens, R. pauciflora. Herb: Indigofera triquetra. Geophytic Herbs: Aristea lugens, Babiana angustifolia, B. latifolia, B. odorata, B. secunda, Hesperantha pallescens, H. spicata subsp. fistulosa, Lachenalia liliflora, L. mediana var. rogersii, L. orthopetala, Lapeirousia fastigiata, Moraea gigandra, M. tulbaghensis, Oxalis fragilis, O. involuta, O. leptocalyx, O. levis, O. macra, O. perineson, O. strigosa, Pelargonium viciifolium.

Conservation: This is a critically endangered vegetation unit. Target 26%, but since 90% of the area has been totally transformed (mainly for cropland), the target remains unattainable. The remnants are found in isolated pockets, usually on steeper ground. So far only a few patches have been included in conservation schemes (e.g. Elandsberg, Paardenberg). Aliens include Acacia saligna (very scattered over 65%), A. mearnsii (very scattered over 62%) as well as several species of Prosopis and Eucalyptus. Alien annual grasses (species of Anagallis, Avena, Briza, Bromus, Lolium, Phalaris and Vulpia) are a primary problem in remnant patches. Other serious aliens include herbs such as Erodium cicutarium, E. moschatum, Echium plantagineum and Petrorhagia prolifera.

National Vegetation Type

Historical area in Cape Town (km2)

% in Cape Town

Current area in Cape Town (km2)

Conserved or managed in Cape Town (km2)

National Ecosystem Status*

Swartland Shale Renosterveld

464

9.4

40

3

CR

*National vegetation types in bold typeface are confined to Cape Town; CR = Critically Endangered, EN = Endangered, VU = Vulnerable, LC = Least Concern


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