The Cape Peninsula, South Africa: physiographical, biological and historical background to an extraordinary hot-spot of biodiversity

The Cape Peninsula, a 470 km² area of rugged scenery and varied climate, is located at the southwestern tip of the Cape Floristic Region, South Africa. The Peninsula is home to 2285 plant species and is a globally important hot-spot of biodiversity for higher plants and invertebrates. This paper provides a broad overview of the physiography, biological attributes and history of human occupation of the Peninsula. The Peninsula is characterized physiographically by extremely high topographical heterogeneity, very long and steep gradients in annual rainfall, and a great diversity of nutrient-poor soils. Thus, the Peninsula supports a high number of habitats and ecological communities. The predominant vegetation is fynbos, a fire-prone shrubland, and 12 broadly characterized fynbos types have been described on the Peninsula. Animal community structure, especially with regard to invertebrates, is poorly known. Vertebrate community structure is probably strongly influenced by nutrient poverty and recurrent fire. Generally, most vertebrates are small and typically occur in low numbers. Some invertebrates play keystone roles in facilitating ecological processes. Human occupation of the Peninsula was limited, until relatively recently, by nutrient poverty. After Dutch colonization in 1652, direct and indirect impacts on the natural ecosystems of the Peninsula escalated dramatically, and by 1994, some 65% of original natural habitat was either transformed by urbanization and agriculture, or invaded by alien plants. Nonetheless, there is still excellent potential to conserve the Cape Peninsula's remaining biodiversity.     

Profiling a besieged flora: endemic and threatened plants of the Cape Peninsula, South Africa

The Cape Peninsula (area: 471 km²), situated at the south-western extremity of the Cape Floristic Region, has exceptionally high plant species richness (2285 species and infraspecific taxa) and numbers of endemic (90; 88 species and two infraspecific) and threatened (141; 138 species and three infraspecific) taxa (termed species from here on). This biodiversity is threatened by urban development and the spread of invasive alien plants. Peninsula endemics are concentrated in a few, predominantly species-rich families and these correspond well with endemic-rich families in other areas of the Cape Floristic Region. A high level of similarity exists between families with threatened and families with endemic species. A frequency analysis of the biological traits of both endemic and threatened species shows that low growing, ant-dispersed shrubs are over-represented in both groups. Endemics are most likely to be non-sprouters, but threatened plants do not have a specific post-fire regeneration strategy. Threatened species have higher frequencies of geophytes, sprouters and wind-dispersed species compared to endemic species. Numbers of endemic and threatened species are not randomly distributed with regard to occurrence in vegetation types and patterns are similar for both groups. The habitat and biological profiles of both endemic and threatened species suggest that they are highly vulnerable to extinction as a result of increasing rates of alien plant infestation, urbanization and inappropriate fire regimes.     

Current and future threats to plant biodiversity on the Cape Peninsula, South Africa

The biodiversity of the Cape Peninsula (49127 ha in extent) has been considerably affected by various factors since European settlement in 1652. Urbanization and agriculture have transformed 37% of the original area of natural vegetation. Lowland vegetation types have been worst affected, with almost half of the transformation occurring in one of the 15 recognized vegetation types. Vegetation at high altitudes has been little affected by urbanization and agriculture, but alien trees and shrubs are now threatening biodiversity in these areas. Of the area not affected by urbanization and agriculture 10.7% is currently under dense stands (>25% canopy cover) of alien plants and another 32.9% is lightly invaded. Dense stands of Acacia cyclops, the most widespread invader, cover 2510 ha, 76% of the total area under dense alien stands. This paper assesses the impacts of these factors on aspects of the plant biodiversity of the area, namely, the distribution of major vegetation types and of endemic, rare and threatened plant taxa and of taxa in the Proteaceae (a prominent element in almost all communities, taken as an indicator of overall plant biodiversity).Possible future impacts on biodiversity are assessed by considering the effects of several scenarios involving increased urbanization and changes to alien plant control strategies and further spread over the next 50–100 years. The worst-case scenario for urbanization sees the area under natural vegelation reduced to 12163 ha (39.3% of its extent in 1994, or 24.8% of its original extent). Under this scenario almost a quater of the 161 endemic, rare and threatened (special) taxa are confined totally to urban areas; 57.4% of the known localities of these taxa, and 40.1% of the remaining localities of Proteaceae taxa are transformed. Dense alien stands currently affect 29.8% of the localities of special taxa known from herbarium records and 8.4% of these taxa currently occur only in areas at present affected by aliens. Clearing all dense stands would result in 62.9% of special taxa having less than half of their known localities affected (49.1% at present). Under this scenario, 92% of Proteaceae taxa have more than 75% of their localities unaffected by aliens. If clearing is confined to specific areas (the Cape Peninsula Protected Natural Environment or all publicly-owned land) and the aliens spread further outside these areas, the area of natural vegetation remaining shrinks (to 82.4% of the current extent if control is confined to public land). The further losses in biodiversity associated with these scenarios are described. If control programmes collapse and all potentially invadable land is occupied by dense alien stands, only 407 ha of natural vegetation would remain (1.5% of the current extent).The probability of the various scenarios materializing is discussed. To minimize further losses in biodiversity it is essential that: (1) a major initiative is launched immediately to clear (firstly) the 10184 ha of lightly invaded vegetation and then the 3313 ha of densely invaded vegetation; (2) no urban development be permitted within the boundaries of the Cape Peninsula Protected Natural Environment; (3) a systematic programme of prescribed burning (linked to the alien control programme) is initiated; and (4) contingency measures are implemented to improve the status of seriously threatened taxa, habitats and vegetation types.     

Management of the natural ecosystems of the Cape Peninsula: current status and future prospects

The Cape Peninsula is an area of outstanding natural beauty and exceptional biodiversity, worthy of proclamation as a World Heritage Site. The area is dominated by fynbos vegetation, usually managed by means of prescribed burning, together with various programmes aimed at the control of invasive alien plant species. Effective management of the Peninsula is bedevilled by the fact that the area is controlled by no less than 14 different public bodies, resulting in fragmentation of effort and the lack of a standardized approach to management. Historically, many official and unofficial investigations have called for this problem to be resolved, without success. The lack of coherent, focused, and well funded fire and alien weed control management plans for the entire Peninsula is a serious deficiency. Despite this, considerable progress has been made towards the establishment of a database for the Peninsula, and the development of decision support systems that can utilize this database for rational management. Adoption of such a system would provide a powerful uniting tramework that would standardize and influence the management approaches adopted by the various controlling authorities.     

Fossil wood charcoal assemblages from Elands Bay Cave, South Africa: implications for Late Quaternary vegetation and climates in the winter-rainfall fynbos biome

Aim The aim of this paper is to analyse fossil charcoal deposits, largely identified to the species level and spanning a sequence from the late Holocene to < 40,000 BP , in order to reconstruct Late Quaternary vegetation and climatic patterns in the western (winter-rainfall) fynbos biome of South Africa. Location The charcoals were excavated from the Elands Bay Cave (32°19S, 18°20E) on the semiarid (200–250 mmyr^?1), winter-rainfall coastline of the western fynbos biome. Methods Patterns in the charcoal data set over time were sought by manual sorting of the charcoal×sample matrix, as well as by subjecting the data to multivariate analysis. Palaeoclimatic reconstruction was attempted by comparing the climatic controls on contemporary vegetation communities that resembled the fossil assemblages. Charcoal diversity was modelled using sample age and number of charcoal fragments as explanatory variables. Results The fossil assemblages ranged from xeric communities (similar to those presently occurring at the site) during the Holocene, to more mesic thicket and fynbos vegetation in the terminal Pleistocene, to Afromontane forest and riverine woodland communities after about 18,000 BP . Diversity of the charcoal samples increased monotonically with increasing sample age. Main conclusions The results suggest that, unlike the eastern fynbos biome, which is under fundamentally different climatic controls, soil moisture conditions in the western part of the biome were higher in the Last Glacial than during the Holocene. This scenario may help to explain the higher regional richness and associated diversification in the western than eastern part of the biome.     

A new system for understanding the biodiversity in different nature reserves:capacity,connectivity and quality of biodiversity

In this paper,we propose a new system for understanding the biodiversity in different conservation areas.It includes three aspects:the capacity,the connectivity and the quality.The capacity refers to the numbers of biodiversity,including absolute and relative richness of the vegetation types Nv and Dv = (Nv-1)/lnA,species numbers S and richness of species dGI = (S- 1)/lnA,and germ plasm resources within a nature reserve,and also the potential biological living space offered by the natural resource.It comprises the total biological resources in a nature reserve.The connectivity refers to the flux of biodiversity,including similarity and connected status of the vegetation types SILi = 2z/(x + y) and species numbers SIc = 2z/(x + y) among different nature reserves.The quality refers to the stability of biodiversity,including relative species richness index RSLi = d/dmax,relative vegetation richness index RVLi =Dv/Dmaxv,fastness to invasion species fLi = 1-Si/St,weighted values,representativeness and vulnerability of special vegetations,special species,CITES species and rare species as the protected targets.     

A new system for understanding the biodiversity in different nature reserves: capacity, connectivity and quality of biodiversity

In this paper, we propose a new system for understanding the biodiversity in different conservation areas. It includes three aspects: the capacity, the connectivity and the quality. The capacity refers to the numbers of biodiversity, including absolute and relative richness of the vegetation types N _v and D _v =(N _v −1)/lnA, species numbers S and richness of species d _Gl =(S − 1)/lnA, and germ plasm resources within a nature reserve, and also the potential biological living space offered by the natural resource. It comprises the total biological resources in a nature reserve. The connectivity refers to the flux of biodiversity, including similarity and connected status of the vegetation types SI _Li =2z/(x + y) and species numbers SI _C =2z/(x + y) among different nature reserves. The quality refers to the stability of biodiversity, including relative species richness index RS _Li =d/d _max, relative vegetation richness index RV _Li =D _v /D _maxv , fastness to invasion species ƒ _Li =1−S _i /S _t , weighted values, representativeness and vulnerability of special vegetations, special species, CITES species and rare species as the protected targets.     

The NSW Environmental Services Scheme: Results for the biodiversity benefits index, lessons learned, and the way forward

Summary   In 2002 the Environmental Services Scheme (ESS) was launched in New South Wales, Australia. Its aim was to pilot a process to provide financial incentives to landholders to undertake changes in land use or land management that improved the status of environmental services (e.g. provision of clean water, healthy soils, biodiversity conservation). To guide the direction of incentive funds, metrics were developed for use by departmental staff to score the benefits of land use or land management changes to a range of environmental services. The purpose of this paper is to (i) report on the development of one of these metrics – the biodiversity benefits index; (ii) present the data generated by field application of the metric to 20 properties contracted to the ESS; and (iii) discuss the lessons learned and recent developments of the metric that aim to make it accessible to a wider range of end-users and applications.     

Integrating conservation and development: effective trade-offs between biodiversity and cost in the selection of protected areas

Strategies are needed for reconciling competing demands at the regional level when areas are to be selected for protection and there are associated costs, possibly equivalent to forgone development opportunties. As an alternative to the fixed scaling (or weighting) of costs and benefits required by cost-benefit analysis, multi-criteria analyses allow the exploration of alternative weightings and a summary trade-off curve to determine preferred solutions. For alternative sets of areas, total cost could be plotted against total represented biodiversity, but a more consistent approach should look at trade-off space at the level of individual areas. For a given weighting, an area is assigned protection if and only if its contribution to total biodiversity, CB, exceeds its equivalent cost, EC (in biodiversity units). Because CB for a given area depends on which other areas are also protected, it can be more or less than EC. Here we develop an iterative strategy for selecting areas, such that, for a given weighting, an area is in the final protected set if and only if its final CB value is greater than its EC value. Sensitivity analysis is used to identify those areas that: (1) are assigned protection even when low weight is given to biodiversity, or (2) are not assigned protection even when high weight is given to biodiversity. This approach is applicable in principle to any surrogate measure for biodiversity; here examples are presented in which environmental data are summarized as an environmental space.     

Flexibility and the use of indicator taxa in the selection of sites for nature reserves

'Minimum' sets of complementary areas represent all species in a region a given number of times. In recent years, conservation assessments have centred around the evaluation of these 'minimum' sets. Previous research shows little overlap between 'minimum' sets and existing nature reserves and between 'minimum' sets for different taxonomic groups. The latter has been used as an argument to discount the use of indicator taxa in the selection of sites for nature reserves. However, these 'minimum' set analyses have only considered a single set for each taxonomic group when there are, in fact, a large number of equally valid 'minimum' sets. We present new methods for evaluating all of these alternative 'minimum' sets. We demonstrate that if all of the sets are evaluated, significantly higher levels of overlap are found between 'minimum' sets and nature reserves, and pairs of 'minimum' sets for different taxonomic groups. Furthermore, significantly higher proportions of species from non-target taxonomic groups are recorded in the 'minimum' sets of target groups. Our results suggest that previous conservation assessments using 'minimum' sets may have been unduly pessimistic.     

Saying it with genes,species and habitats: biodiversity education and the role of zoos

This paper considers the role of zoological gardens as vehicles for teaching about biodiversity and conservation. The general importance of conservation and biodiversity education is outlined in the context of Agenda 21 and the Global Biodiversity Strategy, and the unique niche of zoo education for meeting these challenges is defined. This includes the exhibition of real live animals, accessibility. immediacy, popularity, egalitarianism and the unique combination of strengths and resources offered by zoo education departments. Effective zoo education for biodiversity conservation depends on answering certain criticisms (including behavioural distortion, ecological context and people/animal relationships); working within the available resource framework; and careful strategic planning that considers appropriate messages, target audiences and communication methods. Future zoo education trends might include developing the unique niche; teaching about zoos' role in interactive management; and the contribution of zoo networks to education.     

A comparison of the catchment sizes of rivers,streams, ponds,ditches and lakes: implications for protecting aquatic biodiversity in an agricultural landscape

In this study we compared the biodiversity of five waterbody types (ditches, lakes, ponds, rivers and streams) within an agricultural study area in lowland England to assess their relative contribution to the plant and macroinvertebrate species richness and rarity of the region. We used a Geographical Information System (GIS) to compare the catchment areas and landuse composition for each of these waterbody types to assess the feasibility of deintensifying land to levels identified in the literature as acceptable for aquatic biota. Ponds supported the highest number of species and had the highest index of species rarity across the study area. Catchment areas associated with the different waterbody types differed significantly, with rivers having the largest average catchment sizes and ponds the smallest. The important contribution made to regional aquatic biodiversity by small waterbodies and in particular ponds, combined with their characteristically small catchment areas, means that they are amongst the most valuable, and potentially amongst the easiest, of waterbody types to protect. Given the limited area of land that may be available for the protection of aquatic biodiversity in agricultural landscapes, the deintensification of such small catchments (which can be termed microcatchments) could be an important addition to the measures used to protect aquatic biodiversity, enabling ‘pockets’ of high aquatic biodiversity to occur within working agricultural landscapes. Guest editors: R. Céréghino, J. Biggs, B. Oertli & S. Declerck The ecology of European ponds: defining the characteristics of a neglected freshwater habitat     

Rotifer communities of floodplain lakes of the Brahmaputra basin of lower Assam (N.E. India): biodiversity, distribution and ecology

The rotifer communities of 15 acidic – alkaline and soft – marginally hard water floodplain lakes of the lower Assam valley of the Brahmaputra river basin, characterized by low ionic concentrations, reveal 164 species (178 taxa) belonging to 39 genera and 20 families and represent the richest biodiversity known to date in these ecotones of the Indian subcontinent. Nine species are new to the Indian Rotifera. Cosmopolitan (59.7%) > pantropical (15.2%) > cosmotropical (12.2%) species dominate the taxocoenosis. Biogeographically interesting elements constitute a notable component (13.4%); important members of this category include six Oriental, two Australasian and seven Palaeotropical species. The examined fauna depicts a tropical character with predominance of Lecanespp. (28.0%). Littoral or periphytic rotifers (76.2%) dominate the planktonic species. Rotifers comprise a dominant qualitative (67–103, 79.1±11.0 species) and an important quantitative (mean: 41.1–65.9%) component of zooplankton in all floodplain lakes, register a moderate diversity (mean: 2.036–2.642), low dominance (mean: 0.019–0.216) and high evenness (mean: 0.840–0.893). The examined material indicates several interesting acidophilous elements. Richness depicts significant inverse correlation with pH. Water temperature, conductivity, dissolved oxygen and alkalinity record significant direct relationships with the rotifer abundance. Diversity is influenced by abundance and is also directly correlated with water temperature and conductivity. Canonical analysis shows a notable cumulative impact of six abiotic factors on richness, density and diversity.     

Ecological restoration, carbon sequestration and biodiversity conservation: The experience of the Society for Wildlife Research and Environmental Education (SPVS) in the Atlantic Rain Forest of Southern Brazil

Since 1999, SPVS has been involved in three projects that combine two fundamental goals over the course of 40 years: the conservation of one of Brazil's most important remnants of Atlantic Forest and the implementation of projects for carbon sequestration. In addition, there is an interest in replicating these projects in order to restore other degraded areas, protect the Brazilian biomes, and help to diminish deforestation and forest fire, therefore reducing carbon emissions. The acquisition of 19,000 ha of degraded areas of high biological importance in southern Brazil was the first step towards the implementation of the projects. These areas are owned by SPVS, a Brazilian NGO, and are being restored, conserved and transformed into Private Natural Reserves, in partnership with the NGO – The Nature Conservancy, and financed by the companies – American Electric Power, General Motors and Chevron Texaco. The process of forest restoration involves several stages: soil studies, surveying the region's native plants, planning for restoration by means of a Geographical Information System, production of seedlings, application of different techniques for planting (such as manual or mechanised planting with seedlings and stakes), and biomass and biodiversity monitoring. To guarantee the survival of the seedlings on the planted areas, during the first three years, there is a continuous and systematic maintenance programme including weeding of undergrowth, crowing and organic fertilisation. The three projects already planted around 500,000 seedlings of native species until September 2004, and aim to plant a further 300,000 until 2008.     

Freshwater Reserves in Australia: Directions and Challenges for the Development of a Comprehensive,Adequate and Representative System of Protected Areas

The establishment of a system of protected areas that samples all ecosystems, including freshwater environments, in a comprehensive, adequate and representative (CAR) manner is regarded as a cornerstone for the conservation of biodiversity. There have been few quantitative assessments of the comprehensiveness, adequacy and representativeness of freshwater reserves in Australia. This paper reviews and quantifies the effect of classification of freshwater ecosystems for conservation planning, the importance of reservation status and protection measures for developing a CAR reserve system, and aspects of reserve design for freshwater ecosystems. We propose a strategic and iterative process that incorporates these measures to assist in the efficient and effective development of freshwater reserve systems worldwide. However, the provision of suitable water regimes for freshwater reserves presents further ecological and political challenges, and even adequate reservation of freshwater ecosystems may not conserve constituent biodiversity without effective management.     

North-east Atlantic and Mediterranean species of the genus Buffonellaria (Bryozoa, Cheilostomata): implications for biodiversity and biogeography

In this study we revise the cheilostome bryozoan genus Buffonellaria Canu & Bassler, 1927 and its Mediterranean and north-east Atlantic species, thereby addressing several existing problems. First, a lectotype for the type species, Buffonellaria divergens (Smitt, 1873) from Florida, is chosen, which proves to be distinct from the European species. Second, the two hitherto established north-east Atlantic species [ Buffonellaria nebulosa ( Jullien & Calvet, 1903 ) and Buffonellaria porcellanum Arístegui Ruiz, 1987], are redescribed, which were poorly documented until now. Third, close inspection of material, collected from Spitsbergen to tropical West Africa, using scanning electron microscopy reveals that the actual number of species, all previously referred to either B. divergens or Stephanosella biaperta (Michelin, 1848), is distinctly greater in the north-east Atlantic than has been previously acknowledged. As a result, seven new species are introduced ( Buffonellaria acorensis sp. nov. , Buffonellaria antoniettae sp. nov. , Buffonellaria arctica sp. nov. , Buffonellaria harmelini sp. nov. , Buffonellaria jensi sp. nov. , Buffonellaria muriella sp. nov. , and Buffonellaria ritae sp. nov. ), whereas two are left in open nomenclature. With the increase in number of species, the extremely broad geographical range of distribution assumed for B. divergens breaks down to numerous restricted areas. However, although most species have only been reported from a single location, B. arctica sp. nov. seems to have a fairly wide distribution in the Arctic region.  © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 537–566.