Recovery of invertebrate diversity in a rehabilitated city landscape mosaic in the heart of a biodiversity hotspot
TL;DR: This paper investigated the invertebrate response to alien pine plantations, their removal in comparison with natural vegetation, recovering indigenous forests and a botanical garden around Cape Town, South Africa, within a biodiversity hotspot.
About: This article is published in Landscape and Urban Planning.The article was published on 2009-10-30. It has received 71 citations till now. The article focuses on the topics: Botanical garden & Species richness.
Citations
More filters
TL;DR: Although indicator taxa are considered to be generally unreliable as broad indicators of biodiversity, they may serve a useful function in identifying ecological characteristics or monitoring the effects of habitat management.
Abstract: Bioindicators, as taxa or functional groups, are widely used as indicators of environmental change, specific ecological factors or taxonomic diversity. The use of ecological, environmental and biodiversity indicators, is reviewed here. Although indicator taxa are considered to be generally unreliable as broad indicators of biodiversity, they may serve a useful function in identifying ecological characteristics or monitoring the effects of habitat management. Use of only a narrow range of taxa may be unreliable, and is particularly vulnerable to distortion by a small number of invasive species. Taxa also need to be selected to reflect the specific ecosystem being studied. It is recommended that isopods be used for soil systems (if there is sufficient local diversity), in some areas earthworms or mites may be useable but are generally too difficult to identify to be practically useful. In the ground layer indicator sets could include ants, millipedes, molluscs (snails in particular), ground beetles, harvestmen and gnaphosid spiders. Foliage-inhabiting indicators could comprise ants, chrysomelid leaf beetles, theridiid spiders and arctiid moths. Ants, orthopterans and butterflies may be appropriate for use in open habitats. These basic sets should be supplemented by other taxa where appropriate resources and taxonomic expertise are available.
346 citations
Cites background from "Recovery of invertebrate diversity ..."
...Some studies have included them as indicators of the progress of habitat restoration (Pryke and Samways 2009; Riggins et al. 2009)....
[...]
...Most species have poor dispersal abilities and are slow to recolonise disturbed areas (Pryke and Samways 2009)....
[...]
...They may take a long time to return to a recovered site and so indicate habitat quality or the advanced stages of habitat recovery (Pryke and Samways 2009)....
[...]
TL;DR: Different approaches need to be considered, including the systematic phasing out of commercial forestry in zones where it delivers low returns, and the introduction of more effective, focussed and integrated, region-specific approaches to the management of invasive stands of conifers.
127 citations
TL;DR: The first systematic literature review conducted to evaluate both the quantity and topics of research conducted on odonates in urban ecosystems finds the need for more studies regarding behavioural ecology and life-history traits in response to urbanisation, and a need to investigate the mechanisms behind diversity trends beyond pollution.
Abstract: The expansion of urban areas is one of the most significant anthropogenic impacts on the natural landscape. Due to their sensitivity to stressors in both aquatic and terrestrial habitats, dragonflies and damselflies (the Odonata) may provide insights into the effects of urbanisation on biodiversity. However, while knowledge about the impacts of urbanisation on odonates is growing, there has not been a comprehensive review of this body of literature until now. This is the fi rst systematic literature review conducted to evaluate both the quantity and topics of research conducted on odonates in urban ecosystems. From this research, 79 peer-reviewed papers were identifi ed, the vast majority (89.87%) of which related to studies of changing patterns of biodiversity in urban odonate communities. From the papers regarding biodiversity changes, 31 were performed in an urban-rural gradient and 21 of these reported lower diversity towards built up city cores. Twelve of the cases of biodiversity loss were directly related to the concentrations of pollutants in the water. Other studies found higher concentrations of pollutants in odonates from built-up catchments and suggested that odonates such as Aeshna juncea and Platycnemis pennipes may be candidate indicators for particular contaminants. We conclude by identifying current research needs, which include the need for more studies regarding behavioural ecology and life-history traits in response to urbanisation, and a need to investigate the mechanisms behind diversity trends beyond pollution.
86 citations
Cites background from "Recovery of invertebrate diversity ..."
...…vegetation cover and biodiversity of plants was associated with increased odonate richness and overall evenness in Austria (Chovanec et al., 2002), Germany (Goertzen & Suhling, 2013), France (Jeanmougin et al., 2014), and South Africa (Samways & Steytler, 1996; Pryke & Samways, 2009), among others....
[...]
...Pryke & Samways (2009) Plants and invertebrates South Africa Natural and recovering forests (riverine and nonriverine), natural and recovering fynbos, botanical gardens and alien pine plantations Taxa richness and abundance, species accumulation curves, non-parametric estimators of richness,…...
[...]
...…gardens rich in indigenous plants, and surprisingly the botanical gardens presented the highest species richness and abundance, especially compared with alien pine plantations (Pryke & Samways, 2009), providing evidence that botanical gardens represent a major refuge for invertebrate species....
[...]
TL;DR: In this paper, the effect of alien plantation trees on functional biodiversity is investigated in a large-scale landscape transformation and contingent habitat loss in South Africa, and the authors conclude that the adverse effect from the alien trees into the margin of the remnant ecological networks (ENs) is significant for biodiversity conservation and for providing ecosystem services.
Abstract: Large scale landscape transformation and contingent habitat loss are among the greatest threats to ecological integrity and ecosystem health. One of the mitigation approaches used to deal with these pressures is to leave interconnected corridors and nodes as remnant ecological networks (ENs) within the transformed landscape. The South African forestry industry has already allocated 500,000 ha, one-third of the plantation holdings, consisting predominantly of natural grassland, as ENs among and within timber plantations. These ENs are intended to maintain structural, compositional and functional biodiversity. However, little scientific research is available on the effectiveness of these huge ENs for biodiversity conservation and maintenance of natural ecosystem function, although initial findings are encouraging. While the local adverse effect of alien plantation trees on functional biodiversity is not in dispute, it is at the scale of the whole landscape where there is much interest in determining how effective these ENs are in maintaining the untransformed portion of the transformed landscape in a close-to-natural state. As these ENs are extensive, species beta diversity is a consideration in addition to alpha diversity. Initial findings reveal diminished ecological integrity in narrow corridors due in part to the adverse edge effect from the alien trees into the margin of the EN. Quality of the ENs is of great importance for maintaining functional diversity, with human disturbance reducing their effectiveness. First findings, and their application to the Framework for Ecosystem Service Provision, suggest that these ENs are significant for biodiversity conservation and for provision of ecosystem services. Nevertheless, still much more research is required on a greater range of taxa, and their interactions, to improve the design of these ENs for ecological and evolutionary processes.
83 citations
Cites background from "Recovery of invertebrate diversity ..."
...At this scale, plantation forestry (i.e. stands of alien trees) has been shown to be highly detrimental to biodiversity (Samways and Moore 1991; Armstrong and van Hensbergen 1994, 1996; Armstrong et al. 1998; Pryke and Samways 2009)....
[...]
...stands of alien trees) has been shown to be highly detrimental to biodiversity (Samways and Moore 1991; Armstrong and van Hensbergen 1994, 1996; Armstrong et al. 1998; Pryke and Samways 2009)....
[...]
TL;DR: In this paper, the authors outline the legal obligations to deal with invasive alien plants, the history of control operations and the scientific rationale for their implementation, and the concerns that have been raised about the operations.
Abstract: The Table Mountain National Park is a 265 km protected area embedded within a city of 3.5 million people. The park contains an extremely diverse flora with many endemic species, and has been granted World Heritage Site status in recognition of this unique biodiversity. Invasive alien plants are arguably the most significant threat to the conservation of this biodiversity, and the past decade has seen the implementation of aggressive programs aimed at the removal of invasions by these plants. These invasive alien plants include several species of trees, notably pines (Pinus species) and eucalypts (Eucalyptus species), which historically have been grown in plantations, and which are utilized for recreation by the city’s residents. In addition, many citizens regard the trees as attractive and ecologically beneficial, and for these reasons the alien plant control programs have been controversial. I briefly outline the legal obligations to deal with invasive alien plants, the history of control operations and the scientific rationale for their implementation, and the concerns that have been raised about the operations. Evidence in support of control includes the aggressive invasive nature of many species, and the fact that they displace native biodiversity (often irreversibly) and have negative impacts on hydrology, fire intensity, and soil stability. Those against control cite aesthetic concerns, the value of pine plantations for recreation, the (perceived) unattractive nature of the treeless natural vegetation, and the (incorrect) belief that trees bring additional rainfall. The debate has been conducted through the press, and examples of perceptions and official responses are given. Despite opposition, the policy promoting alien plant removal has remained in place, and considerable progress has been made towards clearing pine plantations and invasive populations. This conservation success story owes much to political support, arising largely from job creation, and a strong body of scientific evidence that could be cited in support of the program.
80 citations
References
More filters
Book•
30 Sep 1988
TL;DR: In this paper, the authors define definitions of diversity and apply them to the problem of measuring species diversity, choosing an index and interpreting diversity measures, and applying them to structural and structural diversity.
Abstract: Definitions of diversity. Measuring species diversity. Choosing an index and interpreting diversity measures. Sampling problems. Structural diversity. Applications of diversity measures. Summary.
10,957 citations
01 Jan 2002
TL;DR: Canoco as discussed by the authors is a software package for multivariate data analysis, with an emphasis on dimesional reduction (ordination), regression analysis, and the combination of the two, constrained ordination.
Abstract: Canoco is a software package for multivariate data analysis, with an emphasis on dimesional reduction (ordination), regression analysis, and the combination of the two, constrained ordination. Canoco makes effective and powerful ordination methods easilyt accessible for scientists wanting to infer and visualize pattern and structure in complex multivariate data, e.g. biologists researching the relations between plant and animal communities and their environment. Canoco contains linear and unimodal ordination methods, with the possibility to account for background variation specified by covariates. In combination with extensive facilities for permutation tests, these methods have proven to be remarkably effective in solving applied research problems.
7,481 citations
TL;DR: The importance of using 'reference' sites to assess the true richness and composition of species assemblages, to measure ecologically significant ratios between unrelated taxa, toMeasure taxon/sub-taxon (hierarchical) ratios, and to 'calibrate' standardized sampling methods is discussed.
Abstract: Both the magnitude and the urgency of the task of assessing global biodiversity require that we make the most of what we know through the use of estimation and extrapolation. Likewise, future biodiversity inventories need to be designed around the use of effective sampling and estimation procedures, especially for 'hyperdiverse' groups of terrestrial organisms, such as arthropods, nematodes, fungi, and microorganisms. The challenge of estimating patterns of species richness from samples can be separated into (i) the problem of estimating local species richness, and (ii) the problem of estimating the distinctness, or complementarity, of species assemblages. These concepts apply on a wide range of spatial, temporal, and functional scales. Local richness can be estimated by extrapolating species accumulation curves, fitting parametric distributions of relative abundance, or using non-parametric techniques based on the distribution of individuals among species or of species among samples. We present several of these methods and examine their effectiveness for an example data set. We present a simple measure of complementarity, with some biogeographic examples, and outline the difficult problem of estimating complementarity from samples. Finally, we discuss the importance of using 'reference' sites (or sub-sites) to assess the true richness and composition of species assemblages, to measure ecologically significant ratios between unrelated taxa, to measure taxon/sub-taxon (hierarchical) ratios, and to 'calibrate' standardized sampling methods. This information can then be applied to the rapid, approximate assessment of species richness and faunal or floral composition at 'comparative' sites.
4,245 citations
Book•
12 Dec 1996TL;DR: In this paper, the authors describe how to design ecological experiments from a statistical basis using analysis of variance, so that we can draw reliable conclusions, and explain the logical procedures that lead to a need for experiments.
Abstract: Ecological theories and hypotheses are usually complex because of natural variability in space and time, which often makes the design of experiments difficult. The statistical tests we use require data to be collected carefully and with proper regard to the needs of these tests. This book, first published in 1996, describes how to design ecological experiments from a statistical basis using analysis of variance, so that we can draw reliable conclusions. The logical procedures that lead to a need for experiments are described, followed by an introduction to simple statistical tests. This leads to a detailed account of analysis of variance, looking at procedures, assumptions and problems. One-factor analysis is extended to nested (hierarchical) designs and factorial analysis. Finally, some regression methods for examining relationships between variables are covered. Examples of ecological experiments are used throughout to illustrate the procedures and examine problems. This book will be invaluable to practising ecologists as well as advanced students involved in experimental design.
3,854 citations
Book•
01 Jan 2006
TL;DR: The logo of the South African National Biodiversity Institute is based on the striking inflorescence of Strelitzia reginae, a native of the Eastern Cape and KwaZulu-Natal that has become a garden favourite worldwide as mentioned in this paper.
Abstract: The plant genus Strelitzia occurs naturally in the eastern parts of southern Africa. It comprises three arborescent species, known as wild bananas, and two acaulescent species, known as crane flowers or bird-of-paradise flowers. The logo of the South African National Biodiversity Institute is based on the striking inflorescence of Strelitzia reginae, a native of the Eastern Cape and KwaZulu-Natal that has become a garden favourite worldwide. It symbolises the commitment of the Institute to promote the sustainable use, conservation, appreciation and enjoyment of the exceptionally rich biodiversity of South Africa, for the benefit of all people.
2,730 citations