Top PDF Biodiversity, Biogeography, and Conservation of Freshwater Fishes in Gabon

Biodiversity, Biogeography, and Conservation of Freshwater Fishes in Gabon

Biodiversity, Biogeography, and Conservation of Freshwater Fishes in Gabon

Freshwater ecosystems cover less than 0.01% of Earth's surface but are home to approximately 40% percent of the world's fish biodiversity. Much of this diversity is concentrated in large tropical rivers, including the Amazon (961 species), Mekong (309 species), Congo (375 species), and the Ogooué River in Gabon (351 species). Freshwater ecosystems are among the most threatened in the world and 36% of freshwater fishes that have been evaluated qualify as endangered by the IUCN. Human development, in particular dam construction, has changed the morphology, hydrology, and functioning of many freshwater ecosystems which has influenced the structure and dynamics of biological communities and ecosystem services. But the impacts of dam development on diverse tropical river systems remain poorly understood. In the central African nation of Gabon, a total of 38 potential hydropower dam sites have been identified, including 28 in the Ogooué watershed. Gabon’s Ogooué River harbors at least 350 species of fish and is the 4th largest river in Africa by discharge (following the Congo, Niger, and Zambezi). The Ogooué flows for 1,200 km and drains roughly 75% of the country of Gabon, but with a rural density of <5 inhabitant/km2 and only one dam in the watershed, the Ogooué is considered one of the world’s most pristine large tropical rivers (Braun et al. 2017). Proposed dams and their reservoirs will increase Gabon’s energy
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Spatial heterogeneity in the Mediterranean Biodiversity Hotspot affects barcoding accuracy of its freshwater fishes

Spatial heterogeneity in the Mediterranean Biodiversity Hotspot affects barcoding accuracy of its freshwater fishes

This is the first large-scale study that uses DNA barcode data to estimate conservation priorities from a nearly complete freshwater fish fauna of a globally important BH. The barcodes and associated vouchers, from 3165 individuals from 498 Mediterranean freshwater fish spe- cies, will serve as baseline for all forthcoming related studies in the region. The freshwater fish diversity in the Mediterranean BH with its 23 different ecoregions (Abell et al. 2008) is indeed remarkable, but remains underestimated. This reaffirms that even well-known faunas still harbour unrecognized elements. If drainage- specific species lists are available, DNA barcoding is a powerful tool for specimen identification using rapid, distance-based methods for clustering DNA barcodes into species – an important notion for applications in local monitoring. The scale effect shown here demon- strates that species identification becomes more chal- lenging as DNA barcode libraries grow in species numbers and geographical coverage, underpinned by the unexpected level of incongruence between morpho- logical- and molecular-based species numbers. Some proportion of the described species might be attribut- able to a historical oversplitting of the European fresh- water fish fauna by taxonomists. This may explain some of the observed incongruences; nonetheless, we refrain from synonymizing different taxa based solely on COI data, but argue that our findings may initiate necessary revisions. The results reveal the lack of a single molecu- lar distance threshold for discriminating allopatric fresh- water fish species and highlight the value of integrative and iterative identification strategies (Fujita et al. 2012; J€orger et al. 2012; Carstens et al. 2013). Greater accuracy from the refined GMYC method (multiple thresholds and model averaging) indicates a true value gain of
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Global biogeography of reef fishes: a hierarchical quantitative delineation of regions

Global biogeography of reef fishes: a hierarchical quantitative delineation of regions

Reef fishes represent one of the best candidates to conduct a quantitative assessment of biogeographical regions worldwide owing to their high diversity (with nearly 6,500 species), their well- known taxonomy [12,13,14], and the well-documented geograph- ical distributions of a very large number of species. Thresher [15] provided the first attempt to statistically analyze relationships between marine areas based on relative species richness of 46 reef fish families; however, he did not define biogeographical regions. Likewise, Bellwood and Wainwright [6] delineated areas based upon species richness but also did not specifically define biogeographical regions. More recently, Floeter et al. [14] used reef fish checklists across the Atlantic to define biogeographical regions using parsimony analysis to match the regional boundaries with known geographical barriers. Similar approaches have also been used by Robertson and Cramer [16] to define biogeograph- ical regions in the Eastern Tropical Pacific (ETP) and by Kulbicki [17] in the South Pacific. These quantitative studies, however, have either been spatially restricted, did not take into account species identity, or did not define distinct biogeographical regions. Obtaining consistent, quantitative, biodiversity patterns remains crucial in testing hypotheses about the spatial organization or large-scale functioning of reef fish assemblages. For example, the ‘‘Coral Triangle’’ or Indo-Australian Archipelago (IAA) is the subject of much debate on the role of speciation and dispersal processes in shaping this biodiversity hotspot e.g. [6,18–25]. There is an implicit suggestion, in many studies, that the peak in reef fish diversity found within the IAA defines it as a biogeographical region often termed the ‘Coral Triangle’. However, a clear delineation of this region, based on species composition, remains elusive and needs to be quantitatively assessed. This discussion extends to the broader topic of the biogeography of reef fishes and the large-scale processes underpinning the geographical distribu- tion patterns of species. In particular, works on connectivity [26,27,28], dispersal [29,30], mid-domain [19], latitude gradients [31,32], hot-spots [33,12], large-scale distributions [34], evolu- tionary origins and dispersal over evolutionary timescales [35,36], conservation planning [37,38], energy input [39,40] and biodi- versity partitioning [41] could all benefit from the identification of large scale species pools corresponding to biogeographical regions that are delineated by quantitative approaches with known accuracy and precision.
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Genetic structure and biogeography of three commercially important African freshwater fishes: Lates niloticus, Bagrus docmak and Bagrus bayad

Genetic structure and biogeography of three commercially important African freshwater fishes: Lates niloticus, Bagrus docmak and Bagrus bayad

Bagrus docmak (Forsskal, 1775), or Semutundu, is a Siluroid catfish widely distributed in African freshwater rivers including the Nile, Chad, Niger, Volta, and Senegal, as well as many of Africa’s large lakes (i.e. Lakes Victoria, Edward, George, Albert, Turkana and Tanganyika). Regional declines in East Africa have been reported for the species, mainly as a result of over fishing and competition from the introduced Nile perch, Lates niloticus (Lévêque, 1997). Bagrus docmak has been displaced from open waters of the lakes and is currently restricted to mouths of large rivers (Goudswaard and Witte, 1997). Farming B. docmak is considered a viable option to reduce the fishing pressure on wild populations; however, attempts to domesticate the fish have been unsuccessful. Prior to this research project, there were no genetic resources, or information on the species’ genetic stock structure to guide conservation planning strategies of wild populations, or to identify appropriate broodstock source populations for restocking, or farming. Accordingly, the first informative microsatellite DNA markers for B. docmak were developed for utility in studies aimed at resolving its natural stock structure.
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A critical evaluation of literature on freshwater fishes research in India

A critical evaluation of literature on freshwater fishes research in India

Bano et al., 2015 studied Fish biodiversity and conservation aspects in an aquatic eco-system in River Narmada. Icthyodiversity refers to a variety of fish species, depending on context and scale; it could refer to alleles or genotypes within piscian population, to species of life forms within a fish community, and to species or life forms across aquaregimes. 40 fish species, 25 genera, 15 families and 6 orders were recorded in the three stations of Narmada near Hoshangabad Region. Among them the Cyprinidea contribute 63.64% of their total population. Due to some anthropogenic activities fish diversity of this river is in decline mode. Sarkar et al., 2015 studied A Review on the Fish Communities in the Indian Reservoirs and Enhancement of Fisheries and Aquatic Environment. In India, reservoirs are playing a crucial role in the fisheries. Fish communities are often used as indicators of environmental quality. In terms of fish diversity altogether 117 fish species were recorded from Indian reservoirs exhibiting rich fish diversity. These reservoirs have both positive and negative impacts on fishes and other aquatic environment. Therefore, present study is emphasized on synthesizing the available information on fish diversity and community structure of the potential Indian Rseservoirs and its effects on fisheries and other aquatic environment in reservoirs in India. Jain et al., 2016 studied diversity of Icthifauna in Central India. Biodiversity is the variation in the genetics and life forms of populations, species, communities and ecosystem. Biodiversity affects the capacity of living system to respond to changes in the environment and is essential for providing goods and services from ecosystems. Fish diversity depends on geographical position, varied aquatic ecological conditions, health of aquatic bodies and optimum exploitation of the commercial fish species, enforcement of laws, rules and regulations and their implementation and fish habitat restoration programs. They enlisted many fish species in Central India.
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The impact of coal fly ash power station on distribution and biodiversity of freshwater fishes in Rupnarayan river, West Bengal, India

The impact of coal fly ash power station on distribution and biodiversity of freshwater fishes in Rupnarayan river, West Bengal, India

In India impact of thermal power fly ash effluents in the fisheries diversity in rivers was also done by several workers (Naik et al., 2013; Sukla and Sing, 2013; Pitchaikani et al., 2010; Wallia and Mehra, 1997 and 1998). Rupnarayan river is one of the significant rivers in west Bengal that need serious concentration in its management and conservation of fishery resources. Detailed studies on this river are still lacking except Dinda (2014).Here we focused the fish diversity of Rrupnarayan river of Purba Medinipur district at Kolaghat are decreases due to spontaneously discharges of coal fly ash in this river. It is clear from this study the river water parameters like temperature, pH, BOD, DO, alkalinity and suspended solid
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Rangelands Biodiversity Conservation and Management

Rangelands Biodiversity Conservation and Management

Government policies have often been basic causes of deterioration of rangeland biodiversity. In most cases, policy framework for biodiversity conservation remains weak in many sectors. This endangers the continued use by pastoralist of their better rangeland areas because, even if the government does not directly alienate land for farming, subsequent land disputes between farmers. The imposition of land tenure changes, settlement and irrigation schemes, state farms, national park and game and forest reserves often removes valuable dry season grazing areas for use by pastoralists. Loss of these high potential rangelands concentrates growing populations of pastoralists and livestock on smaller areas of less productive rangelands, leading to increased competition for and overexploitation of rangeland resources. The ranches have interfered with the flexibility and mobility of traditional grazing systems needed to maintain both and optimal number of pastoralists and rangeland biodiversity and productivity (Fratkin, 1994). Generally, there is tendency to have several institutions dealing with the same resource. Spooner (1994) cited in GoT (1998), examining institutional structures for the managing of biodiversity have identified several institutional weaknesses: such as lack of effective co-ordination, overlaps in the mandate and functioning of various agencies leading to inter agents conflicts, gaps in coverage of biodiversity issues, lack of legal authority among responsible agencies and inexperience which that lack of sufficient capacity in planning and implementation of the conservation programs.
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Biodiversity conservation in agricultural landscapes

Biodiversity conservation in agricultural landscapes

Firstly, biodiversity outcomes of AEMs may be moderated by the surrounding landscape, with noticeable effects only in structurally simple and intensively farmed landscapes, but with only marginal effects in more complex landscapes (Batáry et al., 2011; Concepción et al., 2012). In these landscapes, extensive farming and high amounts of non-crop habitats already support a relatively high level of biodiversity (Tscharntke et al., 2005; Kleijn et al., 2011). Yet, there is no landscape- or situation-based approach to the implementation of most AEMs, and current economic incentives have not been sufficient to attract farmers in intensively managed and high-yielding arable regions (Kleijn & Sutherland, 2003; Quillérou & Fraser, 2010). Instead, participation in AEMs has concentrated to extensively farmed regions where their efficiency is hampered, while intensive farming has largely stayed on the path of business as usual. For instance, organic farming – one of the most commonly and widely implemented AEMs – is in Sweden largely concentrated in forest-dominated regions where arable farming is only marginal (Official Agricultural Statistics, Swedish Board of Agriculture). Thus, it is questionable whether these subsidies are targeting areas where they have the largest impact on biodiversity (Winqvist et al., 2012; Tuck et al., 2014).
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Updated checklist of the freshwater and estuarine fishes of French Guiana

Updated checklist of the freshwater and estuarine fishes of French Guiana

Climate change has already been suggested as the cause of biodiversity changes in French Guiana. Over the last 50 years a rise of around 2°C in the average annual temperature has been observed in some zones, which may be the cause of deterioration in plant biodiversity (Fonty et al., 2009). This warming could alter the flow rates and vegetation cover of the rivers. It could also have biological implications for some species, for example, altering the sex ratio of Hoplosternum littorale (Hostache et al., 1995), with the risk of disrupting population dynamics. It is important to extend genetic stu- dies of populations of species common to different rivers, such as the work carried out on Guyanancistrus brevispinis by Cardoso and Montoya-Burgos (2009), in order to better understand the gene flow and identify the exchange zones. The information gained from these various measures will enable us to better understand the potential risks to fish diver- sity and, where appropriate, take action to limit their impact. These approaches must be coupled with biological and eco- logical studies of the species. Tejerina-Garro et al. (2006) developed a river quality index based on species assembla- ges to help the monitoring of French Guiana rivers to meet the European Water Framework Directive recommendations (see de Mérona et al., 2012). These complementary studies and tools will help to highlight vulnerable stages of species life cycle and allow better management of the anthropic pres- sures (fishing by local populations, agriculture, urbanism, etc) in sensitive zones, and priority protection measures in the case of gold mining activities (Mol and Outboter, 2004; Mol et al., 2012) particularly for the most vulnerable spe- cies (Jégu and Keith, 2005; Covain et al., 2012; Mol et al., 2012). This will facilitate the implementation of sustainable exploitation of the fish stocks (Jégu et al., 2003; de Figuei- redo Silva et al., 2012). The first phases of this programme should, as a priority, be implemented in protected zones such as the Parc amazonien de Guyane and the regional reserves.
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Biotechnology and biodiversity conservation: are they conflicting

Biotechnology and biodiversity conservation: are they conflicting

The methods of biotechnology can be applied to the study of virtually any biological phenomenon and will in some cases have practical applications for maintaining biodiversity. Conversely, threats to biodiversity by biotechnology also need to be considered. It is clear that, each application of Biotechnology needs to be studied carefully on a case-by-case basis, like any other new technology. A valid concern is the possible effect of Bt-crops and similar plants on non-target insects. The Bt-crops contain a gene coding for an insecticidal protein originally produced by the soil bacterium Bacillus thuringensis. They were developed to make the plants resistant to a particular, highly damaging pest and have been quite successful in reducing pesticide input when infestation rates are high. In laboratory studies, Losey showed that the pollen from Bt-corn could kill larvae of the Monarch butterfly when a large amount of pollen was sprayed on the larvae's favorite food plant, commonly called milkweed (Lowe et al., 2000). This shows that the impact of transgenic crops on non-target organisms or on native biodiversity should be given due emphasis.
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Philanthrocapitalism, biodiversity conservation and development

Philanthrocapitalism, biodiversity conservation and development

This section explores three similar sites where conservation philanthropy is the most recent in a series of forms of capitalist exploitation, and where philanthropy, capitalism, ad conservation are engaging in different ways to the cases discussed above. The first is Karukinka Natural Park (272,000 hectares), located on Isla Grande, Tierra del Fuego. Environmentalists see Karukinka as untouched wilderness, yet it has millennia of indigenous occupation, and has been integrated into global capitalist since sheep farming was established in the 1880s. Its origins lie in the 1994 purchase by Trillium (US timber corporation) of large tracts of sub-Antarctic nothofagus hardwood forest for US$26 million (Klepeis & Laris, 2006) 1 . Although Trillium saw their project as a pioneering example of sustainable logging, committed to maintaining areas unlogged and to selective logging, it was opposed by Chilean and international environmentalists. Some opponents argued against any kind of logging, despite any claims to sustainability made, because it would inevitably damage the fragile forest, and because it would open up the area to extensive exploitation. This was mixed with wider opposition to neoliberalism, to discontent over the relative political neglect of austral regions in Chile, and to concerns that locals would see little benefit from logging (Klepeis & Laris, 2006; Saavedra et al, 2011). Due to poor management and the high cost of infrastructure development in such harsh terrain, the project faced financial difficulties and defaulted on loans. In 2002, Trillium’s land in Chilean Tierra del Fuego was acquired by their
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The conservation of biodiversity is one of the most

The conservation of biodiversity is one of the most

To illustrate how the risk-adjusted performance of ecosystem services varies with the level of biodiversity, we synthesized data from two kinds of studies conducted in temperate grass- lands, which are among the best-studied ecosystems (table 1). The first kind of study systematically manipulated species di- versity and measured levels of an important ecosystem ser- vice, plant biomass production or yield. The second study surveyed natural levels of biodiversity and measured the as- sociated yield within the sampling location. We analyzed the risk-adjusted performance for each kind of study separately. Data sources. We considered the plant species within an experimental or sampling plot as a portfolio that produced a certain level of harvestable standing plant biomass or yield. To find the relationship among mean performance, variance in performance, and species diversity, we extracted data from several recent and prominent experiments reporting on the link between plant species diversity and associated produc- tivity (Hooper and Vitousek 1997, Hector et al. 1999, Tilman et al. 2002). The studies were either conducted separately within different grassland ecosystems in the United States (Hooper and Vitousek 1997, Tilman et al. 2002) or con- ducted simultaneously but replicated in different countries within continental Europe and the United Kingdom to facilitate systematic, broadscale comparison (Hector et al. 1999). In general, the experimental studies systematically manipulated the initial composition and abundance of dif- ferent plant species (biodiversity) in 4-m 2 experimental field
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Biodiversity and Health: Implications for Conservation

Biodiversity and Health: Implications for Conservation

Presently, although there are few sites explicitly designed and managed to deliver conservation and human health gains in tandem, the potential for synergistic bene- fits could be substantial. The opportunities to adopt such a strategy are considerable, given the rapid rates of urbanisation globally and that many regions are yet to be developed (Nilon et  al. 2017). Urbanisation will not be geographically homoge- nous, chiefly taking place in small cities comprising less than 500,000 inhabitants across the Global South (United Nations 2015). This vast conversion of land to built infrastructure will undoubtedly pose a threat to biodiversity, not least because most of it will occur in extremely biodiverse regions such as the Brazilian Atlantic Forest and Guinean Forests of West Africa (Seto et al. 2012). Formal conservation protec- tion is therefore imperative to prevent extinctions (Cincotta et al. 2000; Brooks et al. 2006; Venter et al. 2014). Justifying the need to protect natural environments in and around where people live to deliver a multi-faceted suite of objectives is more likely to be persuasive to decision-makers than a rationale based solely on conservation. In already established towns and cities, green spaces can be ‘retrofitted’ to provide complementary conservation and human health gains (for further information, see Hunter et al. Chap. 17, and Heiland et al. Chap. 19, both this volume). For example, initiatives such as the Biophilic Cities network (http://biophiliccities.org/) promote biodiversity as a central tenet of urban planning and management, so that improve- ments in human health and well-being arise from co-existence (Beatley and van den Bosch 2018). Metrics related to levels of biodiversity, wildness, tree cover and green space accessibility are included as indicators against which the performance of individual cities can be gauged.
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Richness and endemism of helminth parasites of freshwater fishes in Mexico

Richness and endemism of helminth parasites of freshwater fishes in Mexico

Distribution records of 152 adult helminth taxa parasites of freshwater fishes in Mexico were analysed to determine areas of high richness and endemism. Distribution maps were prepared for each taxon and overlaid onto a map of Mexico divided into 1 ¥ 1 degree grid-cells. Richness was determined by counting recorded helminth species in each grid-cell. A corrected weighted endemism index was calculated for each grid-cell, and the relationship between richness and endemicity was analysed with an Olmstead–Tukey corner test of association. Five areas of high richness and endemism were identified: (1) Los Tuxtlas and the Papaloapan river basin, on the Gulf of Mexico; (2) the Grijalva-Usumacinta basin near the Gulf of Mexico coastal plain; (3) the Yucatan Peninsula; (4) the Sierra de Manantlán Biosphere Reserve in western Mexico; and (5) the Pátzcuaro lake, in central Mexico. The distribution of richness and endemism of helminth parasites of freshwater fishes in Mexico is congruent with distributional patterns described for other freshwater taxa in Mexico. Patterns of richness and/or endemism in the studied areas can be explained by the ichthyological composition of their bodies of water. The present study establishes an objective way of analysing the relationship between richness and endemicity, and suggests that helminths can make valuable contributions to regionalization of geographical areas and for identification of rich and biologically complex areas with potential for conservation of aquatic systems. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 94, 435–444.
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Chemical ecology and conservation biogeography of Rhododendron ponticum L

Chemical ecology and conservation biogeography of Rhododendron ponticum L

Conservation biogeography is defined as the application o f biogeography in conservation (Ladle and W h itta k e r 2011); and in broad term s encompasses the study o f the d istrib u tio n o f biodiversity, at landscape scale and above, applied in particular to issues o f conservation. The emergence o f these topics o f investigation in recent decades has been greatly aided by the developm ent o f tools and techniques such as Geographic In fo rm a tio n Systems (GIS) and species distrib u tio n m odelling (SDM), w hich have perm itte d ever m ore com plex and com putation ally intensive analyses over large scales and at high resolution. These developm ents have resulted in new abilities to tackle ever m ore com plicated questions in relation to biodiversity conservation, and as a result, to arrive at solutions w hich w ould not have been possible to achieve before. For instance, th e practical u tility o f SDMs in conservation biology is extrem ely diverse (Guisan and Thuiller 2005), and com m only features in tasks such as the design o f ecological corridors or setting protected area boundaries, predicting the likelihood o f w here new populations o f rare or endangered species may best be located, in assessment o f invasive species and th e ir potentia l spread, and quantifying changes in habitat su ita b ility fo r target taxa under clim ate change. The above listed tasks may be undertaken as part o f purely fundam ental tests o f th e o re tica l hypotheses (Austin 2007), ranging all the way to fu lly applied applications, to inform practical decision-m aking processes and conservation planning (Franklin et al. 2014).
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Biodiversity and distribution of polar freshwater DNA viruses

Biodiversity and distribution of polar freshwater DNA viruses

The Arctic viral metagenomes were similar in their taxonomic composition, mainly dominated by ssDNA and unknown viruses. Find- ing a large fraction of unaffiliated viral metagenomic reads is a common issue in aquatic environments (28). The abundance of ssDNA viruses was observed even after estimating a 100-fold increase bias of the Phi29 polymerase for circular ssDNA genomes. Most polar contigs obtained had no highly similar ( ≥ 65%) genomes in the databases, in agreement with the notion that our knowledge of viral diversity in nature is very sparse (10). We were able to find circular contigs rep- resentative of the recently described RNA-DNA hybrid viruses (29), which sustain previous reports indicating that these viruses may be globally distributed (29, 30). Overall, the viral communities retrieved from samples IR1 and IR2 were the most similar of the Arctic viromes. This is not surprising because they originate from the same area and were obtained in the same season (late summer) when both presented no ice cover. The Lake Tenndammen community (SvL2) was most si- milar to Lake Linnevatnet’s virome (Lv1), despite the fact that they were taken at different seasons and that Lake Linnevatnet presents a more complex food web including fish. The virome from sample SvL1, derived from melted top ice of Lake Nordammen, was found to be the most different among the deeper-sequenced Arctic samples. This seems to indicate that although composed of similar viral taxa, this melted top ice environment is not representative of a large water body environment. The taxonomic composition of Arctic communities separated them from viromes from freshwater samples in other regions of the world studied but was similar to that of the Antarctic spring. Arctic viral com- munities were found to share genes and large genomic regions. We de- tected three frequent genomes, likely corresponding to highly stable and abundant viral species represented in four of five Arctic viral com- munities. The fact that we were not able to detect more frequent species from these similar and neighboring environments, despite the high cov- erage attained, indicates that viral communities from these environments are highly dynamic in their rank abundance structure, which agrees with theoretical predictions made for marine phage communities (31).
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Biodiversity and distribution of polar freshwater DNA viruses

Biodiversity and distribution of polar freshwater DNA viruses

Viruses constitute the most abundant biological entities and a large reservoir of genetic diversity on Earth. Despite the recent surge in their study, our knowledge on their actual biodiversity and distribution remains sparse. We report the first metagenomic analysis of Arctic freshwater viral DNA communities and a comparative analysis with other freshwater environments. Arctic viromes are dominated by unknown and single-stranded DNA viruses with no close relatives in the database. These unique viral DNA communities mostly relate to each other and present some minor genetic overlap with other environments studied, including an Arctic Ocean virome. Despite common environmental conditions in polar ecosystems, the Arctic and Antarctic DNA viromes differ at the fine-grain genetic level while sharing a similar taxonomic composition. The study uncovers some viral lineages with a bipolar distribution, suggesting a global dispersal capacity for viruses, and seemingly indicates that viruses do not follow the latitudinal diversity gradient known for macroorganisms. Our study sheds light into the global biogeography and connectivity of viral communities.
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Twenty landmark papers in biodiversity conservation

Twenty landmark papers in biodiversity conservation

Although not a conservation biology paper per se, Hardin’s classic essay (Hardin, 1968) changed the way we think about managing natural resources that lack definitive ownership. The thesis of the “tragedy of the commons” is that individuals are inherently selfish and usually place their own interests first in using commonly owned resources, thereby resulting in their depletion. Hardin used a hypothetical and simplified situation based on medieval land tenure in Europe (herders sharing a common parcel of land) on which each herder was entitled to graze his cattle. Each herder maximized his gains by putting additional cattle onto the land, even if the carrying capacity of the common was exceeded and overgrazing ensued. The herder, by making an “individually rational decision,” received all the benefits from his cattle, but could in the process deplete the common resource for the entire group. If all herders make such selfish decisions then the common will be depleted, jeopardizing the livelihoods of all. Hardin’s paper is now a central paradigm in natural resources management (e.g., fisheries); however, his work has been criticized most notably by Elinor Ostrom – the first woman to be awarded the Noble Prize in economics in 2009. In her classic work, Ostrom (1990) showed that when communities are given the freedom to self-govern, they are, under certain conditions, able to use the commons sustainably. Another controversial theme of Hardin's paper is that an expanding human population is a detriment to the planet and its ability to support human existence, and thus he implies that humanity needs to be educated to relinquish the freedom to breed without limit (for more recent discussion see Ehrlich & Pringle, 2008).
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INTERNATIONAL LEGAL STREAK FOR BIODIVERSITY CONSERVATION

INTERNATIONAL LEGAL STREAK FOR BIODIVERSITY CONSERVATION

INTRODUCTION: The state of the conservation of biodiversity at the outset of the twenty first century is not the same as it was decades ago. The proliferation of private enterprise and neoliberal practices, combined with rapid integration of global processes, have reduced the potential impact of international accords and protocols on the environment and sustainable development to meager symbols of complacency and indifference. Major environmental issues have become muddled in international bargaining processes, with hardly any direct focus or financial resources devoted to their alleviation. Today the goals commonly expressed by environmentalists include reduction and clean up man made pollution, with future goals of zero pollution, reducing societal consumption of non-renewable fuels, development of alternative green, low-carbon or renewable energy sources, conservation and sustainable use of scarce resources such as water, land and air, protection of representative or unique or pristine ecosystems, preservation and expansion of threatened or endangered species or ecosystems from extinction, the establishment of natural and biosphere reserves Scholarly Research Journal's is licensed Based on a work at www.srjis.com
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Community structure and biogeography of shore fishes in the Gulf of Aqaba, Red Sea

Community structure and biogeography of shore fishes in the Gulf of Aqaba, Red Sea

The higher species richness and abundance in 12 m depth can be explained by the high productivity of the seagrass meadows and by feeding migrations of fishes from the coral reef to the seagrass beds (Ogden 1980; Robblee and Ziemann 1984; Quinn and Ogden 1984; Kochzius 1999). Invertebrate feeders are significantly more abundant at the seagrass-dominated site (M.A. Khalaf and M. Kochzius, unpublished data), where they can utilise the rich crustacean fauna. Nocturnal feeding migrations of invertebrate feeders from coral reefs into seagrasses are documented for the Atlantic as well as the Indo-Pacific (Weinstein and Heck 1979; Bell and Pollard 1989; Kochzius 1999). Studies in the Caribbean have shown that the biomass of fishes in coral reefs adjacent to seagrass meadows is higher than in reefs without sea- grass beds (Birkeland 1985). Comparison of fisheries from different coral reef regions suggests that coral reefs bounded by extended shallow-water habitats, such as seagrass meadows or mangroves, yield the highest catch. Reefs with a ratio of shallow-water habitat to coral reef of 1:1 or more are very productive (Marshall 1985). De- spite the lack of biomass data in this study, the high abundance of fishes in Al-Mamlah Bay supports these findings. Before the recent closing of this area, it was a favourite fishing ground for local fishermen, indicating a high standing stock and high productivity of fish. These results support the importance of Al-Mamlah Bay as a high productive area along the Jordanian Red Sea coast. A comparison of six seagrass meadows along the Jorda- nian coast revealed the highest seagrass biomass (g/m 3 )
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