Coastal-marine discontinuities and synergisms: implications for biodiversity conservation

Coastal-marine biodiversity conservation must focus increasingly at the level of the land- and seascape. Five cases illustrate discontinuities and synergisms and how system changes may take place. For Caribbean coral reefs, the result of overfishing and disease has been a shrinkage in the entire system, the effects of which may cascade through the coastal seascape. For Beringia, patterns of benthic diversity are best understood in a manner that matches the multiscale, integrated dynamics of weather, ice, marine mammal feeding, and community structure. In the case of US East Coast estuaries, oyster reefs may be keystone elements, with important effects on functional diversity. Large-scale coastal systems depend upon the connectivity of fresh and marine waters in the coastal zone, having implications for the apparent stochasticity of coastal fisheries. And, for a coastal barrier-lagoon site, a state change may be described in terms of a combination of succession, the attainment of a quasi-equilibrium state, and disturbance. A profound problem for conservation is that there is very little information about the relationship between species diversity and ecological function. Coastal-marine biodiversity conservation is best addressed at the level of the land- and seascape.     

Linking biodiversity to ecosystem function: implications for conservation ecology

We evaluate the empirical and theoretical support for the hypothesis that a large proportion of native species richness is required to maximize ecosystem stability and sustain function. This assessment is important for conservation strategies because sustenance of ecosystem functions has been used as an argument for the conservation of species. If ecosystem functions are sustained at relatively low species richness, then arguing for the conservation of ecosystem function, no matter how important in its own right, does not strongly argue for the conservation of species. Additionally, for this to be a strong conservation argument the link between species diversity and ecosystem functions of value to the human community must be clear. We review the empirical literature to quantify the support for two hypotheses: (1) species richness is positively correlated with ecosystem function, and (2) ecosystem functions do not saturate at low species richness relative to the observed or experimental diversity. Few empirical studies demonstrate improved function at high levels of species richness. Second, we analyze recent theoretical models in order to estimate the level of species richness required to maintain ecosystem function. Again we find that, within a single trophic level, most mathematical models predict saturation of ecosystem function at a low proportion of local species richness. We also analyze a theoretical model linking species number to ecosystem stability. This model predicts that species richness beyond the first few species does not typically increase ecosystem stability. One reason that high species richness may not contribute significantly to function or stability is that most communities are characterized by strong dominance such that a few species provide the vast majority of the community biomass. Rapid turnover of species may rescue the concept that diversity leads to maximum function and stability. The role of turnover in ecosystem function and stability has not been investigated. Despite the recent rush to embrace the linkage between biodiversity and ecosystem function, we find little support for the hypothesis that there is a strong dependence of ecosystem function on the full complement of diversity within sites. Given this observation, the conservation community should take a cautious view of endorsing this linkage as a model to promote conservation goals. Received: 2 September 1999 / Accepted: 26 October 1999     

An American naturalist's impressions on Australian biodiversity and conservation

Editorial Introduction

An American naturalist's impressions on Australian biodiversity and conservation     

Fossil insects and ecosystem dynamics in wetlands: implications for biodiversity and conservation

We review the uses of fossil insects, particularly Coleoptera (beetles) and Chironomidae (non-biting midges) from ancient deposits to inform the study of wetland ecosystems and their ecological and restoration processes. In particular, we focus on two contrasting ecosystems, drawing upon research undertaken by us on British raised mire peats and shallow lake systems, one an essentially terrestrial ecosystem, the other aquatic, but in which wetland insects play an important and integral part. The study of raised mire peats suggests that faunal stability is a characteristic of these wetland systems, over what appear to be extensive periods of time (up to several millennia), whilst studies of shallow lake ecosystems over recent timescales indicates that faunal instability appears to be more common, usually driven by increasing eutrophication. Drawing upon a series of fossil Coleoptera records spanning several thousand years from Hatfield Moors, south Yorkshire, we reconstruct in some detail the mire’s ontogeny and fluctuations in site hydrology and vegetation cover, illustrating the intimate association between substrate, topography and peat development. A comparison between fossil and modern beetle populations indicates that the faunal characteristics of this mire and its adjacent neighbour, Thorne Moors, become established during the early phases of peat development, including its rare endemics, and that the faunal biodiversity on the sites today is dictated by complex site histories. The over-riding characteristic of these faunas is of stability over several thousand years, which has important implications for the restoration of degraded sites, especially those where refugial areas are limited. In contrast, analyses of fossil Chironomidae from shallow lakes allow researchers to track changes in limnological status and while attempts have been made to reconstruct changes in nutrient levels quantitatively, the chironomids respond indirectly to such changes, typically mediated through complex ecosystem dynamics such as changes in fish and/or macrophyte communities. These changes are illustrated via historic chironomid stratigraphies and diversity indices from a range of shallow lakes located across Britain: Slapton Ley, Frensham Great Pond, Fleet Pond, Kyre Pool and Barnes Loch. These sites have shown varying degrees of eutrophication over recent timescales which tends to be associated with a decline in chironomid diversity. While complex functional processes exist within these ecosystems, our evidence suggests that one of the key drivers in the loss of shallow lake chironomid diversity appears to be the loss of aquatic macrophytes. Overall, while chironomids do show a clear response to altered nutrient regimes, multi-proxy reconstructions are recommended for a clear interpretation of past change. We conclude that if we are to have a better understanding of biota at the ecosystem level we need to know more of the complex interactions between different insect groups as well as with other animal and plant communities. A palaeoecological approach is thus crucial in order to assess the role of insect groups in ecosystem processes, both in the recent past and over long time scales, and is essential for wetland managers and conservation organisations involved in long term management and restoration of wetland systems     

Impact of forest size on parasite biodiversity: implications for conservation of hosts and parasites

Studies of biodiversity traditionally focus on charismatic megafauna. By comparison, little is known about parasite biodiversity. Recent studies suggest that co-extinction of host specific parasites with their hosts should be common and that parasites may even go extinct before their hosts. The few studies examining the relationship between parasite diversity and habitat quality have focused on parasites that require intermediate hosts and pathogens that require vectors to complete their life-cycles. Declines in parasite and pathogen richness in these systems could be due to the decline of any of the definitive hosts, intermediate hosts, or vectors. Here we focus on avian ectoparasites, primarily lice, which are host specific parasites with simple, direct, life-cycles. By focusing on these parasites we gain a clearer understanding of how parasites are linked to their hosts and their hosts’ environment. We compare parasite richness on birds from fragmented forests in southern China. We show that parasite richness correlates with forest size, even among birds that are locally common. The absence of some ectoparasite genera in small forests suggests that parasites can go locally extinct even if their hosts persist. Our data suggest that the conservation of parasite biodiversity may require preservation of habitat fragments that are sufficiently large to maintain parasite populations, not just their host populations.     

Managing rock outcrops to improve biodiversity conservation in Australian agricultural landscapes

Summary  Rocky outcrops are prominent geological features in agricultural landscapes worldwide. Reptiles are a major component of these habitats and some species are restricted to, and more abundant on, rocky outcrops than in remnant vegetation. Rock outcrops are important to reptiles because they provide resources that are often limited in the surrounding landscape (e.g. micro-gradients in climatic conditions, basking- and retreat-sites). However, there is a knowledge gap in the literature addressing the conservation value of small, rocky outcrops. Management may be necessary to reverse habitat degradation in these systems. We identify four key areas of management that need to be addressed to improve outcrop habitat values and enhance biodiversity conservation in agricultural landscapes. Specific actions involve: (i) protecting outcrops from processes that cause damage to rock microhabitat, (ii) monitoring and managing changes in vegetation structure to maintain thermally suitable environments, (iii) applying integrated pest animal control and (iv) improving matrix management to enhance inselberg function and landscape connectivity. Further research is required to evaluate the efficacy of different management regimes on outcrop biota. We hope this paper will provide the stimulus for land managers to incorporate rocky outcrops in future biodiversity conservation programmes.     

Bryozoan biodiversity in the New Zealand region and implications for marine conservation

Marine biodiversity and its distribution in the New Zealand region were determined using historical data for an appropriate indicator taxon, the Bryozoa. Bryozoans were identified as belonging to three communities, termed Intertidal/Shelf/Slope (ISS) and Deep-Sea 1 and 2 (DS1 and DS2). Biodiversity was assessed using measures based on relatedness of species, average taxonomic distinctness and variation in taxonomic distinctness. High values of biodiversity for the ISS community are particularly concentrated at both ends of two main islands of New Zealand; the biogenic substratum of the Three Kings Plateau and Foveaux Strait. High values of biodiversity for the DS1 community were primarily located on the seamounts of the northern edge of the Chatham Rise. Values of biodiversity for stations comprising the DS2 community were generally low. The relationship between bryozoan community composition/biodiversity and depth suggested that habitat availability/heterogeneity, sedimentary perturbation and primary productivity could be evoked to explain the pattern of biodiversity observed. The results of the study indicate particular areas of the shelf and deep-sea environment that could be protected in order to conserve New Zealand's marine biodiversity.     

Diversity patterns in savanna grassland communities: implications for conservation strategies in a biodiversity hotspot

For any conservation strategy to be effective, it must be preceded by knowledge of how diversity is configured within the area of interest. Here, data from 40 savanna-grassland sites were used to examine how plant biodiversity and species composition varied across spatial scales at the Kalakad-Mundanthurai Tiger Reserve (KMTR), south India. Grasslands surveyed contained 278 plant species, and were characterized by high spatial variability in species association patterns. Fourteen distinct community assemblages were identified, organized primarily along an elevation gradient in the reserve. Overall, grasslands at KMTR were characterized by the dominance of a few, widespread species. The bulk of species richness, however, resulted from subordinate species with fairly restricted distributions. At low elevations, grasslands had high species richness and species composition differed greatly between sites. Mid-elevation grasslands contained about half the number of species present at low elevations, but sites were more similar in species composition. Richness of high-elevation grasslands was a third of that found at low elevations, but different sites harbored unique sets of species. Herbivore use of grasslands varied between communities and showed patterns that coincided with elevation. Herbivore use of low-elevation communities was high albeit variable, of mid-elevation sites was consistently low, and increased at higher elevations. Tall grass communities were the least utilized by herbivores at all elevations. Most species surveyed were rare and restricted in their distribution suggesting that conservation efforts must, perforce, encompass the entire reserve. However, differences in the structuring of diversity across elevations, and in herbivore use of grasslands, suggest that conservation efforts can be partitioned differentially across locations, specifically targeting low and high elevation grasslands in the reserve.     

Woodland biodiversity, palaeo-human ecology and some implications for conservation management

This paper appraises the role of prehistoric human societies in modifying the natural woodland biodiversity of several regions throughout Scotland. It draws attention to the likelihood that, contrary to popular belief, biodiversity was enhanced by interactions between agricultural communities and woodlands. The possible purposefulness of such interactions is discussed. Mindful of the present concern to re-establish ‘native’ woodlands in many parts of northern Britain, we then review three approaches to the identification of native tree types in Scotland, and conclude that insufficient attention in reafforestation schemes is being paid to (a) the palaeoecological record as a record of native woodland or (b) the likely former high taxonomic diversity of woodlands. Both these failings will lead to the creation of new woodlands lacking in species diversity.     

Freshwater finfish biodiversity and conservation: an asian perspective

Aspects on biodiversity and conservation of the ichthyofauna in the Asian region, in comparison to that of Africa, Europe and North America have been relatively less documented. This paper attempts to evaluate the above aspects in the East, and South and Southeast Asia based on available information in the literature. The familial diversity in inland waters in Asia (121 families) is considerably higher than in African and Latin American. Also, the finfish faunal diversity of 21 major river basins in East, and South and Southeast Asian indicate that species diversity is not necessarily related to familial diversity. The fish fauna in the region considered presently is highly diverse with an estimated cumulative total of 7447 species. Amongst the freshwater fishes the dominant groups are cyprinids (Cyprinidae, about 1000 species), loaches (about 400 species) of the families Balitoridae and Cobitiidae, gobids (Gobiidae, 300 species), catfishes (Bagridae, about 100 species), and the Osphronemidae (85 species). In the region, 462 freshwater finfish species are reckoned to be threatened, accounting for 17.5% of the all finfish species in this status in the world. In the region there are 66 species that are critically endangered and/or endangered, of which 32 are cyprinids, 14 of which are endemic to Lake Lanao, Mindano Island, Philippines. The diversity of freshwater fish species in the region was significantly related to the land area of the different countries in the following manner:

Local and landscape effects on temporary pond zooplankton egg banks: conservation implications

Understanding landscape correlates of local habitat integrity and community structure and the identification of spatial scales at which these associations operate are relevant for management and conservation of unique but globally threatened temporary ponds. We use a multivariate variance decomposition approach to determine taxon-specific associations of zooplankton communities banked in dry pond soils (rotifers, cladocerans, copepods) with local habitat features and landscape characteristics across four spatial scales (100 buffer strip, 1, 5, and 10 km scales). Results show similar degrees of correlation between rotifer and cladoceran communities with local habitat conditions (chiefly water quality). This is interpreted according to life-history traits of component species of wetland propagule banks. Associations with landscape features varied between communities with rotifers correlating with landscape structural features only at the buffer scale while cladocerans showed no significant correlations with landscape characteristics across all scales. Copepods were neither significantly associated with local nor landscape characteristics. The results of this study contrast strikingly with our previous population-based study, where populations of Triops cancriformis and Branchinecta orientales were significantly correlated with landuse features at the broadest scale. The combined results suggest that a three-way management scheme could be useful for conservation of zooplankton resting egg banks in this remnant wetland complex. These schemes could focus on the restoration of wetland water quality, the establishment of vegetated buffer strips around the ponds to counteract degradation resulting from runoff, and reforestation and/or the creation of hedgerows in agricultural catchments to avoid impacts resulting from broad-scale diffuse pollution fluxes. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

森林与人类休戚相关,需要我们更多呵护

1992年6月3-14日,联合国环境与发展大会于巴西里约热内卢召开,大会通过了5个重要文件,其中包括<生物多样性公约>,该公约于1993年12月29日生效.为了纪念公约生效,联合国大会于1994年12月19日通过49/119号决议,将每年的12月29日确定为国际生物多样性日(International Day of Biodiversity).由于12月29日离西方的圣诞节很近,很多国家都很难组织庆祝活动.     

Data exchange gaps in knowledge of biodiversity: implications for the management and conservation of Biosphere Reserves

The knowledge of species occurrence within an area is crucial to develop proper conservation strategies to protect species diversity. Biosphere Reserves (BRs), established to preserve biodiversity and sustainably use their resources, should therefore have precise information of its biodiversity. We compared and evaluated information on threatened and non-threatened vertebrate species available for Spanish BRs from three sources: management documents (MDs), the Global Biodiversity Information Facility index (GBIF), and atlases and red books. Our results suggest that information from any one source was rather partial, to a degree that depended on which vertebrate group was considered. Management documents did list a high percentage of threatened species found in BRs, reaching up to the total number of species of birds and mammals. Species lists overlap between all three sources ranged from 59 % for fish to 84 % for mammals. In addition, there is an inconsistency between national and international threatened species categories and it should thus call for revisions. Even though the information of non-threatened and threatened species occurrence in MDs of Spanish BRs is good, it is necessary to pay attention to amphibian and fish species which are less recorded.     

Composition and structure of macroinvertebrate communities in contrasting open-water habitats in Irish peatlands: implications for biodiversity conservation

The purpose of this study was to consider the relative importance of several habitat variables in explaining the patterns in the structure of macroinvertebrate assemblages in open-water habitats, in relatively intact bogs and fens, which should inform conservation strategies. It was hypothesised that variables relating to the size of the water body would differentiate the communities and that some species would be unique to certain conditions. The macroinvertebrate communities from pools >100 m², 10.1–100 m² and Sphagnum hollows were characterised using sweep sampling for eight intact peatland sites across four bog types, and related to habitat variables including pool size, Sphagnum cover and hydrochemistry. Results showed community composition and structure differed significantly between deep, permanent pools and shallow, drought-sensitive Sphagnum hollows, with larger invertebrates, such as Odonates and Dytiscinae, rarely found in the hollows. Sphagnum cover accounted for a substantial amount of the variation in community composition. An examination of life-history strategies found species dependent on predictable conditions for juvenile development to be more abundant in pools. In contrast, taxa that could delay juvenile development until conditions were favourable were more abundant in Sphagnum hollows. These results highlight the importance of habitat heterogeneity in maintaining macroinvertebrate diversity in peatlands.     

Cryptic diversity in Indo-Australian rainbowfishes revealed by DNA barcoding: implications for conservation in a biodiversity hotspot candidate

The rainbowfishes of the family Melanotaeniidae represent one of the largest radiations of freshwater fishes from the Indo-Australian archipelago. A total of 75 nominal species have been described, among which several have become very popular among tropical fish hobbyists because of their tendency to form large schools of colourful individuals. Facing habitat loss and competition or predation by introduced species, this group has become a priority in the conservation of ornamental fishes in Indonesia. In this context, several expeditions have been conducted between 2007 and 2010 in Indonesian Papua with the aim to initiate a large-scale survey of the genetic resources in this group. We assessed the diversity of the Papua rainbowfishes with DNA barcoding. We sequenced the mitochondrial COI gene for 350 specimens belonging to 53 nominal species throughout the Indo-Australian archipelago. Unexpected levels of cryptic diversity and endemism were detected since additional cryptic lineages were detected in several watersheds from the Vogelkop and the Lengguru massif. DNA barcoding supports the presence of nearly 30 evolutionary lineages among the 15 nominal species sampled in the Vogelkop and all these lineages are endemic to a single lake or watershed. This result highlights that the diversity of the family has been largely underestimated and urges for the identification of conservation priorities in Papua.     

Plants in traditional home gardens: richness,composition, conservation and implications for native biodiversity in Benin

Home gardens have received increasing attention and have been insistently presented as hotspots for agro-biodiversity over the last decades. However, apart from their exceptional high plant species diversity, there is little quantitative evidence of the effectiveness of plant species conservation in home gardens. This study examined this issue by assessing (i) the size and membership of garden flora and the contribution to the maintenance of the national flora, (ii) how home garden flora connects to the larger ecosystem it belongs to and (iii) the conservation status of plant species at the home garden level. 360 home gardens distributed in three agro-ecological zones and nine phyto-geographical districts in Benin were visited and inventoried. Diversity parameters at different taxonomic levels were calculated. Species accumulation and spatial occupancy, multivariate methods and rarity index were also used for data analysis. Findings showed that the 360 studied home gardens hosted up to 14.21% of plant species and 44.32% of plant families of the national flora. Home garden flora was constantly dominated by exotic plant species but strongly connected to their surrounding ecosystems, being composed of at least 60% of plant species from their phyto-geographical districts. Finally, home garden plant species were mostly rare and threatened at the home garden level. In this study, we acknowledge the contribution of home gardens to the maintenance of plant species diversity at regional and global levels than local level. Based on the observed prevalence of exotic species, HG effectiveness in sustainably conserving native plant species biodiversity remains questionable.