PDF superior Conservation planning of vertebrate diversity in a Mediterranean agricultural dominant landscape

Conservation planning of vertebrate diversity in a Mediterranean agricultural dominant landscape

Conservation planning of vertebrate diversity in a Mediterranean agricultural dominant landscape

conservation areas (Natura 2000 Network and current natural protected areas), and connectivity 769.. (b) Higher magnification of the boxed area in (a) that illustrates least- 770[r]

44 Lee mas

Effects of woodland islets introduced in a Mediterranean agricultural landscape on local bird communities

Effects of woodland islets introduced in a Mediterranean agricultural landscape on local bird communities

One of the alternatives proposed for abandoned farm- land is the recovery of forest ecosystems by planting woody species, especially where the lack of propagules, their dis- persers or environmental constraints reduce the potential for natural regeneration. This is the case of large expanses of croplands, olive groves and vineyards in central Spain, where plantations subsidized by the Common Agricultural Policy are increasingly frequent since 1993. With regards to bird conservation, the aim of these programs could be to promote forest species diversity in areas where open-habi- tat species have declined. However, this is not always easy. Firstly, the different structure of plantations compared to that of natural forests condition their functionality for forest species. In addition, increase in area availability of a given type of habitat only triggers colonization by spe- cialist species when the connectivity at the landscape and biogeographic scales is enough to allow the dispersal of individuals. If plantations cannot attract forest species and exclude open-habitat species, we may conclude that their spread will lead to a decline of overall bird diversity. Thus, it is necessary to find a proper design and management
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10 Lee mas

Vegetation diversity, composition and structure in a cattle agro landscape of Matiguás, Nicaragua [Spanish]

Vegetation diversity, composition and structure in a cattle agro landscape of Matiguás, Nicaragua [Spanish]

Abstract: Vegetation diversity, composition and structure in a cattle agro-landscape of Matiguás, Nicaragua. The diversity, composition and structure of vegetation in a cattle landscape in Matiguás, Nicaragua was characterized, and the floristic and structural differences of six types of habitats (secondary forests, riparian forests, charrales, live fences and pastures with high and low tree cover) were compared. A total of 3 949 trees of 180 species and 52 families were recorded. Forty six percent of the total trees reported for the landscape were represented by Guazuma ulmifolia (18.5%), Bursera simaruba (13.2%), Tabebuia rosea (6.3%), Enterolobium cyclocarpum (4.2%) and Albizia saman (3.4%). Many of the dominant species in the landscape were typical of open and disturbed areas. There were significant differences between the different habitats in the patterns of tree species richness, abundance, diversity, structure and floristic composition. The riparian forests had greater tree richness (p=0.0001) and diversity (p=0.0009) than other habitats. The floristic composition varied across habi- tats, with pairs of habitats sharing between 18.4 and 51.6% of the same tree species, and with clear differences in composition between the forested (riparian and secondary forests) and agricultural habitats. Of the habitats studied, the riparian forests and secondary forests seem to have greatest value for the conservation of the flora in the agropaisaje because they have the greatest species richness, and maintain small populations of endangered species. On the basis of the study, we recommend including agricultural landscapes in strategies to conserve tree diversity and suggest measures to ensure the maintenance of tree diversity in the Matiguas landscape. Rev. Biol. Trop. 53(3-4): 387-414. Epub 2005 Oct 3.
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Reproductive activity of anurans in a dominant agricultural landscape from central-eastern Argentina

Reproductive activity of anurans in a dominant agricultural landscape from central-eastern Argentina

Conclusions. Functional diversity, represented by ecological attributes of species (e.g., habitat preferences, reproductive activity, and reproductive modes) is a better predictor of environmental health than species diversity by itself (Ernst et al., 2006), because species are lost from areas subjected to anthropogenic disturbance when their ecological requirements are no longer met (De Souza and Eterovick, 2011). Accordingly, the present study shows that both reproductive microhabitat use and breeding periods are modified in the agricultural site, suggesting that land use for agriculture has an effect on the breeding ecology of amphibians in central-eastern Argentina. Considering the present results, and in order to protect all environments within PDNP (continental and island areas) from negative effects of agricultural activities conducted in nearby areas, we recommend establishing a buffer zone or peripheral damping area for the Park (according to Neumann, 1997) to preserve wildlife and enhance conservation values of the protected area. Further studies are necessary to continue evaluating possible plasticity in reproductive strategies and ecological responses to different environmental variables over long periods, to incorporate other variables in the analysis of the ecological risk for amphibians (Lajmanovich et al., 2010) produced by conversion of native ecosystems to soybean cropping areas.
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Bird diversity and conservation of Alto Balsas (Southwestern Puebla), Mexico

Bird diversity and conservation of Alto Balsas (Southwestern Puebla), Mexico

Abstract: Knowledge of the composition of the bird community in Alto Balsas (southwestern Puebla, Central Mexico) is needed for management programs aiming at protection and conservation of bird species and their habitats I studied sites with tropical deciduous forest. Data were obtained during 1666 hours of field work in 238 days from March 1998 to September 2000. Six permanent transect (3.5 km long and 100 m wide; 30 to 40 ha in each transect) were used to determine species richness in the study sites. The Shannon-Wiener diversity index was calculated for each site and Sorensen’s index was used to assess similarity between sites. One-way analysis of variance was used to test for differences between sites in species richness and diversity values. A total of 128 species were recorded, Tepexco (n = 75, H´= 3.76) and Puente Márquez (n = 61, H´= 3.62) were the sites that showed the greatest specific richness and diversity. However, species richness and diversity seasonally patterns were similar among sites (ANOVA p > 0.05), with highest diversity during the rainy season. Most species were resident; 42 were migrants. The avifauna was represented by 30 species associated with tropical deciduous forest and 12 from open habitats or heavily altered habitats. Insectivores were the best represented trophic category, followed by carnivores and omnivores. Rev. Biol. Trop. 55 (1): 287-300. Epub 2007 March. 31.
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Testing of leachability and persistence of sixteen pesticides in three agricultural soils of a semiarid Mediterranean region

Testing of leachability and persistence of sixteen pesticides in three agricultural soils of a semiarid Mediterranean region

Leaching, the movement of water and chemicals into deeper soil layers and groundwater is a subject of worldwide interest because a high percentage of drinking water is extracted from groundwater. The objective of this study was to evaluate the potential leach- ing and persistence of sixteen pesticides (one fungicide, three nematicides/insecticides, and twelve herbicides) for three Mediterranean agricultural soils with similar texture (clay loam) but different organic matter content (1.2-3.1%). Adsorption was studied in batch experiments and leaching was tested using disturbed soil columns (40 cm length × 4 cm i.d.). Degradation studies were carried out during 120 days under laboratory conditions. Mobility experiments showed that pesticides can be grouped according to their po- tential leaching. Thus, pesticides showing medium leachability were included in group 1 (referred as G1) while those with high leachability were termed as G2. The differences observed in the leachability can be attributed to the different organic carbon (OC) content in the soils (0.7-1.8%). Values of log K OC were higher in the order: soil C > soil B > soil A, which agrees with the OC con-
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11 Lee mas

Large Scale spatio temporal patterns of mediterranean cephalopod diversity

Large Scale spatio temporal patterns of mediterranean cephalopod diversity

While there have been some studies on Mediterranean fish diversity [12,15,16], no large scale analysis of Mediterranean cephalopod diversity exists. This contrasts with the fact that they play a key role in marine ecosystems, as they are important prey species as well as vora- cious predators [17]. Therefore, fluctuations in their community composition and abundance are likely to have profound consequences for the food webs and ecosystems. Furthermore, cephalopods are important living resources for most Mediterranean countries, sustaining some economically important fisheries in various areas [18]. Being semelparous species with a short generation time of normally one to two years, they can respond rapidly to changes in environ- mental conditions [19]. Temporal changes in their abundance and diversity can therefore sup- ply important information about ecosystem alterations. Despite their importance, the only existing publications looking at their large-scale diversity patterns are species inventories com- paring species richness between the Adriatic Sea, the western and the eastern Mediterranean basin [20,21]. Mangold and Boletzky [20] conclude a general eastward decrease in species numbers and found the Adriatic to contain the lowest species richness, but the more recent study of Bello [21] noted fewer differences between the areas. This is characteristic for species inventories, which, although historically very precious, suffer from biases resulting from differ- ent sampling intensities [22]. More analytical cephalopod diversity studies are restricted to local scales, both in the western [23 – 25] and the eastern [26 – 28] basins. At such local scales, depth was found to be the main diversity driver.
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19 Lee mas

Diversity, threat, and conservation of reptiles from continental Ecuador

Diversity, threat, and conservation of reptiles from continental Ecuador

We obtained locality data points for 406 species of reptiles from three local museum databases—Museo de Zoología at Pontificia Universidad Católica del Ecuador (QCAZ), Museo Ecuatoriano de Ciencias Naturales (MECN), Museo de Historia Natural Gustavo Orcés at Escuela Politécnica Nacional (EPN)—, HerpNET, Global Bio- diversity Information Facility (GBIF), as well as from the literature. We validated each data point in ArcMap v. 10.2 (ESRI 2013) and removed taxonomically incon- gruent records (e.g., localities along the Pacific coast for species known to occur exclusively east of the Andes). Duplicate points (for the same species), as well as points <2 km close to each other were also removed to avoid oversampling bias in the analyses.
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Raptor functional diversity in scrubland-agricultural landscapes of northern-central-Mexican dryland environments

Raptor functional diversity in scrubland-agricultural landscapes of northern-central-Mexican dryland environments

Our results contribute to the limited information related to raptor community ecology in semiarid environments of northern-central Mexico and are useful for agencies dedicated to natural areas management such as the National Commission for Natural Protected Areas (CONANP), the Federal Secretariat for the Environment and Natural resources (SEMARNAT), and the State Secretariat for Ecology and Environmental Management (SEGAM), among others. Our results suggested that if these agencies are interested in maintaining raptor functional attributes in dryland habitats of central Mexico, agriculture should be avoided in some large areas comparable to those of golden eagle territories. We believe that implementation of such strategy is realistic considering both, that agri- culture in these drylands is not highly productive and logistically difficult to implement due to the absence or abundant water sources, and that agriculture in portions of this region covers small proportions of the land. However, alternative development strategies that would both enhance livelihoods of local inhabitants and pro- mote scrubland habitat conservation should be developed.
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19 Lee mas

Evolutionary optimization in dynamic fitness landscape environments

Evolutionary optimization in dynamic fitness landscape environments

In general the conditions of an optimization problem changes by one of the following reasons or a combination of both [1]: 1) The objective function changes itself, 2) The constraints change. A change in the objective function appears when the purpose of the problem changes. Here conditions which were considered desirable before can turn out to be undesirable now and vice versa. Changes in constraints, which modify feasibility of solutions, are related to resources and their availability. Changes can be small or big, soft or abrupt, chaotic, etc. When changes are big, abrupt or chaotic the similarity between solutions found so far and the new ones can be worthless. Even under these hard environments Evolutionary Computation (EC) offers advantages, which are absent in other heuristics when searching for solutions to non-stationary problems. The main advantage relies in the fact that Evolutionary Algorithms (EAs) keep a population of solutions. Consequently, facing the change, they allow moving from a solution to another one to determine if any of them are of merit to continue the search from them instead of from scratch [2]. Goldberg and Smith [3], Cobb[4] and Grefenstette [5] initiated the research related to the behaviour of EAS on dynamic fitness functions between 1987 and 1992. Recently the interest in this area was dramatically incremented [6], [7], [8], [9], [10], [11], [12], [13], [14], and [15]. The following sections are organized as follows. Section 2 presents a definition of dynamic environments studied in this work. Section 3 describes the dynamic test functions used. Section 4 describes the EA. In section 5 the experiments performed are described. In section 6 results are discussed and finally this document shows our conclusions, current and future work.
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11 Lee mas

Landscape  and field scale control of spatial variation of soil properties in Mediterranean montane meadows

Landscape and field scale control of spatial variation of soil properties in Mediterranean montane meadows

Structural equation modeling (SEM) was used to investigate how well our empirical data supported hypothesized relationships among a set of variables. The advantages of SEM in path analysis are related to the possibility of testing the overall agreement between the path model and the data (Hayduk 1987; Loehlin 1987; Mitchell 1992). The hypothetical models describe how variables are linked in terms of direct and indirect effects. The model was evaluated separately for the following gradients: 1) total ion content, 2) acidity, 3) organic matter expressed as carbon, 4) total nitrogen, and 5) total phosphorous. We hypothesized that gradients of soil chemical composition depends on the complex interaction of a set of biotic and abiotic factors interacting at two different spatial scales. The model comprises six control factors, and thirteen direct and indirect effects (paths) (Figure 1).
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Using opportunistic sightings to assess the suitability of Important Marine Mammal Areas (IMMAs) for cetacean conservation in the Western Mediterranean Sea / Uso de avistamientos oportunistas para evaluar la idoneidad de las IMMAs (Áreas Importantes para

Using opportunistic sightings to assess the suitability of Important Marine Mammal Areas (IMMAs) for cetacean conservation in the Western Mediterranean Sea / Uso de avistamientos oportunistas para evaluar la idoneidad de las IMMAs (Áreas Importantes para Mamiferos Marinos) para la conservación los Cetáceos en el Mar Mediterráneo occidental

We assumed that the OS records were collected using a non-systematic design and that they were mainly collected along vessel routes. Thus, due to the (a) possible lack of randomization in the OSs and (b) the size of the study area (geographical background [GB]), we delimited the appropriate GB by selecting the most probable OSs. Thus, from the total OSs of cetaceans, we selected the most probable set of OSs based on their geographic position. In line with Acevedo et al. (2012), we used Trend Surface Analysis (TSA) to assess the probability of each OS according its geographical position. Also in line with these authors, we performed binary stepwise logistic regressions between the occurrence or otherwise of OSs within IMMAs as the target variable. We used different spatial polynomials as independent variables, such as latitude (LAT), longitude (LONG), latitude by longitude (LATLONG), latitude squared (LAT 2 ),
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5 Lee mas

Assesment of biomass and carbon dynamics in pine forests of the Spanish central range: A remote sensing approach

Assesment of biomass and carbon dynamics in pine forests of the Spanish central range: A remote sensing approach

Encouraged by a readily available source of data there has recently been an increased interest by the Spanish research community in relation to remote sensing technologies and the potential application to forest environments, in particular the characterization of forest structure. Vázquez de la Cueva [44] explored relationships between forest structural attributes at the plot level (e.g., height, basal area, and crown canopy closure) and spectral information derived from Landsat Enhanced Thematic Mapper Plus (ETM+; 30 m pixel size) imagery combined with topographic data. The study considered three types of forest in Central Spain and applied a multivariate canonical ordination method. The author found a strong influence of vegetation type on the results, with a low percentage of variance explained precluding development of robust empirical models. Pascual et al. [45] used lidar data and a two stage object based methodology to characterize the structure of Pinus sylvestris L. stands in forests of Central Spain. Five structure types were defined based on height and density parameters. The median and standard deviation of height were found to be the most valuable for definition of structure types, with the approach developed being proposed for operational application suitable for inclusion in forest inventory procedures in support of forest management plans. Merino de Miguel et al. [33] investigated the strength of relations between dasometric parameters and textural variables in Pinus pinaster Ait. stands in Central Spain. The authors used geostatistical tools (i.e., variograms), calculated with orthophotography and IKONOS-2 imagery with original and degraded spatial resolutions. The authors found the strongest correlations when the variogram was calculated for spatial resolutions of 1 m and 2 m. As such, opportunities to further explore the capacity of HSR imagery to estimate a range of forest structural parameters remain.
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252 Lee mas

Result oriented agri environmental climate schemes as a means of promoting climate change mitigation in olive growing

Result oriented agri environmental climate schemes as a means of promoting climate change mitigation in olive growing

PES system to increase soil carbon concentration could also be implemented through the development of a compliance offset market, an example of which is the Carbon Farming Initiative (CFI) developed in Australia. In the CFI, farmers and land managers can earn carbon credits by storing carbon or reducing greenhouse gas emissions on their land; such credits can then be sold to other organizations wishing to offset their emissions. Under a cap-and-trade emissions-trading system, increases in SOC achieved by an unregulated party (olive growing farmers and landowners) can be used to offset emissions from a regulated party within the EU Emissions Trading System (ETS) (Matthews, 2014). Potential buyers would then be involved in a cross-sector partnership, led by the public administration, where farmers’ associations and other interested stakeholders such as intermediaries, industries, monitoring agencies or Conservation, Amenity and Recreation Trusts (Hodge, 2011) can trade the carbon credits. To avoid conflicts arising from international trade and competition issues, the payments could be limited to specific types of farms or farmers —i.e. smallholdings, low income farmers, etc.— or capped to a percentage of total agricultural income.
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20 Lee mas

Phoenix flagships: Conservation values and guanaco reintroduction in an anthropogenic landscape

Phoenix flagships: Conservation values and guanaco reintroduction in an anthropogenic landscape

People consider nature in terms of its utilitarian, intrinsic, and esthetic values (Jepson and Canney 2003; Saunders 2013). These multiple axes of valuation are assessed both cognitively and emotionally (Edwards 1990). Esthetic val- ues have had a particular role in the field of landscape perception, an area that has been extensively studied (e.g., Hull and Stewart 1992; Surova and Pinto-Correia 2008). Although landscape valuation studies typically only consider plant communities, wildlife-viewing experiences can add movement, surprise, or contemplative opportunities to the esthetic appreciation of landscapes (Rolston 1987; Montag et al. 2005; Gobster 2008). People also generally prefer large, colorful, and pretty animal species (Verı´ssimo et al. 2009), which are more likely to gain public attention and therefore to be protected, along with their habitats (e.g., Brambilla et al. 2013). Although a causal link between conservation values and conservation actions can be difficult to establish (Crites et al. 1994; Verı´ssimo 2013), values nonetheless must underlie any consistent, voluntary con- servation behavior. Accordingly, a place will be valued differently according to its landscape- and wildlife-related features and to how they speak, emotionally and cognitively, to a specific group of people (Saunders 2013).
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Biodiversity patterns of coralligenous outcrops over broad spatial and temporal scales in the NW Mediterranean Sea: baseline data for conservation

Biodiversity patterns of coralligenous outcrops over broad spatial and temporal scales in the NW Mediterranean Sea: baseline data for conservation

Long-term monitoring studies of classical high resolution biodiversity data face the difficulty of taxonomic identification. The correct identification of species is a task that requires great taxonomic expertise and involves several problematic aspects, which have become increasingly evident in recent years (Rae et al 2013). Species-level identification for monitoring purposes is an expensive and time- consuming task (Fiori et al 2002). In general, taxonomic expertise on marine benthic species is increasingly in shortage,and the number of scientists able to identify correctly them is decreasing (Balata et al 2011). The necessity of taxonomists and the long-time needed to analyze samples make it difficult to process the high number of replicates required for ecological studies and monitoring surveys (Balata et al 2011; Chapman et al. 1995; Underwood and Chapman 1996; Benedetti-Cecchi et al. 2001). Therefore, the traditional taxonomic approach is today being supplemented by ecological classifications following the concepts of functional groups (FG), morpho-functional groups (MFG), and morphology-based functional groups (MBFG) (Mihaljević et al 2014). In marine ecosystems, morphological–functional groups are widely used to describe benthic assemblages (Vanderklift and Lavery 2000; Konar and Iken 2009). In a same MFG, morpho-functionally similar species are assembled together and are expected to represent a more or less defined functional trait, and thus MFG might be good indicators of ecosystems functioning and of physiological responses to global change (Balata et al. 2011). In this line, several studies have shown that trait-based approaches, which are based on the life traits of species provide general and more predictable rules for community ecology as well as a more mechanistic comprehension of biodiversity effects on ecosystem functioning and process, particularly in the context of global change (McGill et al. 2003, Mouillot et al. 2013).
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Biochar effects on soil quality as evaluated by physical, chemical, and biological parameters

Biochar effects on soil quality as evaluated by physical, chemical, and biological parameters

Some specific changes in soil physical characteristics due to biochar addition have been documented, although most inferences are based on biochar’s general physico-chemical characteristics, and the fact that surprisingly little information has been collected on basic physical parameters has been noted elsewhere (Sohi et al. 2010). Many physical properties are expected to be affected by biochar addition, including structure, porosity and consistency, as well as water retention and aeration through an altered bulk surface area, pore-size distribution, particle density, and particle packing as aggregates (Downie et al. 2009; Mukherjee and Lal 2013). Improvement in soil physical properties can potentially allow higher yields due to an enhanced penetration depth and availability of air and water within the root zone (Downie et al. 2009). In turn, biochar’s persistence in soil might benefit from such physical improvements, due to the poor accessibility of biochar when physically enveloped by soil particles, which could help to enhance the recalcitrant nature of biochar (Brodowski et al. 2006, Nguyen et al. 2008), but also due to its mobility into deeper soil profile layers (Mukherjee and Lal 2013).
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Although, some species found in the irri- gation channels occur in surrounding natural wetlands, the species composition of the irri- gation channels surveyed during the present study differed from natural systems (Rolon et al. 2008, Stenert et al. 2008). The high propor- tion of hydrophytes (51% of species) was one of the differences found in the composition of the macrophytes in the irrigation channel, whereas in natural wetlands, the hydrophytes represented only a small part of the community (e.g. 25%, Rolon et al. 2004). The morphology of the channels (mean water depth of 60cm) limits the establishment of emergent species to the littoral zone; moreover, the depth of studied channels provided more availability of habitats for the establishment of hydrophytes. Another difference in the composition of macrophytes was the high proportion of grasses and sedges, which have represented almost the totality of the emergent species (85% of emergent spe- cies). The high dominance of grasses and sedges verified in studied channels (43%) was higher than observed in rice fields of Southern Brazil and Sri Lanka, where these species represented 46% and 39% of total richness, respectively (Bambaradenya et al. 2004, Rolon & Maltchik 2010).
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20 Lee mas

THE PREDICTS DATABASE: A GLOBAL DATABASE OF HOW LOCAL TERRESTRIAL BIODIVERSITY RESPONDS TO HUMAN IMPACTS

THE PREDICTS DATABASE: A GLOBAL DATABASE OF HOW LOCAL TERRESTRIAL BIODIVERSITY RESPONDS TO HUMAN IMPACTS

Some studies of birds presented additional complications. Some authors presented taxon names as four-letter codes that are contractions of common names (e.g., AMKE was used by Chapman and Reich (2007) to indicate Falco sparve- rius, American kestrel) or of Latin binomials (e.g., ACBA was used by Shahabuddin and Kumar (2007) to indicate Accipiter badius). Some of these codes are valid taxonomic names in their own right. For example, Shahabuddin and Kumar (2007) used the code TEPA to indicate the passerine Terpsiphone paradisi. However, Tepa is also a genus of Hemiptera. Left uncurated, COL recognized TEPA as the hemipteran genus and the Study consequently had a lowest common taxonomic rank of kingdom Animalia, not of class Aves or a lower rank within Aves, as we would expect. Some codes did not appear on published lists (e.g., http://www.birdpop.org/alphacodes.htm, http:// www.pwrc.usgs.gov/bbl/manual/speclist.cfm, http://www. carolinabirdclub.org/bandcodes.html and http://infohost. nmt.edu/~shipman/z/nom/bbs.html) or in the files pro- vided by the authors, either because of typographical errors, omissions or incomplete coverage. Fortunately, codes are constructed by following a simple set of rules – the first two letters of the genus and species of binomials, and a slightly more complex method for common names of North Ameri- can birds (http://infohost.nmt.edu/~shipman/z/nom/bbl rules.html). We cautiously reverse-engineered unrecognized codes by following the appropriate rules and then searched lists of birds of the country concerned for possible matches.
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Diversity of demersal fish assemblages in the Mediterranean

Diversity of demersal fish assemblages in the Mediterranean

Measures of biodiversity change may be useful as indicators if they are respon- sive to manageable drivers of biodiversity loss. However, there are many candidate indicators that are considered to be robust to survey artifacts and sensitive to manage- able impacts. Using extensive survey data on demersal fish assemblages around the Balearic Islands (western Mediterranean) we analyse relationships among ‘traditional’, taxonomic and functional diversity indices, to identify a minimum set of indices that provide a good representation of the different aspects of diversity. Secondly we model the responses of the demersal fish community diversity to bottom trawl fishing pressure. To do so, we used two different approaches: (i) considering fishing effort and depth as continuous explanatory variables; and (ii) grouping samples according to bathymetric sampling strata and contrasting levels of fishing effort. The results show that diver- sity can be described using different complementary aspects such as species richness, evenness, and the taxonomic and functional breadth of the species present in a given community, displaying different responses to fishing pressure. However, the changes in diversity in response to fishing may only be detectable in those communities where the levels of fishing pressure have remained relatively low. When communities have been exposed to high levels of fishing pressure for a long period, the relevant changes in di- versity may have happened long before the onset of monitoring of the fishery, and hence it may be too late to detect differences between levels of fishing effort. This seems to be the case on the middle slope of the Balearic Islands, where vulnerable species have disappeared or are very infrequent, and have been replaced by species better adapted to fishing impacts.
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