In a perfect world, systematic conservation planning would use complete information on the distribution of biodiversity. However, information on most species is grossly incomplete. Two main types of distribution data are frequently used in conservation planning: observed and predicted distribution data. A fundamental question that planners face is - which kind of data is better under what circumstances? We used simulation procedures to analyse the effects of using different types of distribution data on the performance of reserve selection algorithms in scenarios using different reserve selection problems, amounts of species distribution known, conservation targets and costs. To compare these scenarios we used occurrence data from 25 amphibian and 41 reptile species of the Iberian Peninsula and assumed the available data represented the whole truth. We then sampled fractions of these data and either used them as they were, or converted them to modelled predicted distributions. This enabled us to build three other types of species distribution data sets commonly used in conservation planning: “predicted”, “transformed predicted” and “mixed”. Our results suggest that reserve selection performance is sensitive to the type of species distribution data used and that the most cost-efficient decision depends most on the reserve selection problem and on how much we have of the species distribution data. Choosing the most appropriate type of distribution data should start by evaluating the scenario circumstances. While there is no one best approach for every scenario, we discovered that using a mixed approach usually provides an acceptable compromise between species representation and cost. 相似文献
We sought to provide a useful indicator of the presence of endocrine-disrupting contaminants along the marine coast of the
South Pacific using Chilean flounder (Paralichthys adspersus). In light of the lack of information on vitellogenin for this species, we induced, purified, and identified the plasma vitellogenin
of Chilean flounder inhabiting the Chilean coast. Vitellogenin (Vg) from Chilean flounder was purified by size exclusion and
ion-exchange chromatography using plasma from juvenile males induced by injecting 17β-estradiol. The Vg was detected by SDS–PAGE and Western blot analyses using an antibody against turbot (Scophthalmus maximus) vitellogenin. These analyses revealed a protein band of 205 kDa and three minor bands of 120, 90, and 68 kDa. These proteins
were identified as Vg by means of mass spectrometry (LCQ Duo ESI-IT-MS), matching sequences of tryptic peptides to known sequences
for several other fish species. The matches showed the presence of vitellogenin (VgI, VgII, Vg A and Vg B) in Chilean flounder,
similar to species such as mummichog (Fundulus heteroclitus), Japanese medaka (Oryzias latipes), and white perch (Morone americana). These results are discussed in terms of identifying Vg in Paralichthys adspersus with the antibody to turbot Vg. Moreover, we compare the molecular size of Vg from Chilean flounder (large) with that of
other flatfish species. Finally, we discuss the potential use of this molecule as a biomarker for the presence of xeno-estrogenic
compounds along the Chilean coastline. 相似文献
One of the current challenges of global fish farming is developing plant‐based proteins as a feasible substitute for fishmeal in the formulation of aquafeeds. Substitution levels of fishmeal with hydrolyzed soybean meal (HSM) in diets for silver catfish (Rhamdia quelen) were evaluated for growth, protein metabolism and antioxidant activity. The experiment was carried out in a recirculation system of 20 tanks of 250 L. A total of 300 silver catfish juveniles were used to compose five treatments and four replicates per treatment. Levels of soybean hydrolysate (0%, 5%, 10%, 15% and 20%) were tested in diets (39% protein and 3,500 Kcal) for 60 days. Silver catfish growth was higher at all inclusion levels of HSM when compared to the control diet. No change was shown for body protein deposition. The production of nitrogenous compounds in the liver and muscle was also unaffected by any of the diets. The diet containing 20% HSM promoted an increase in the amounts of non‐protein thiols in the gills and brain. The HSM substitution levels of up to 20% of fishmeal in the diet increases growth and contributes to silver catfish antioxidant activity. 相似文献
The objective of this study was to evaluate the effect of dietary addition of the essential oil from Lippia alba (EOLA) on growth performance, biochemical and haematological variables and survival after Aeromonas spp. infection of Nile tilapia juveniles (Oreochromis niloticus). Five diets were evaluated with increasing levels of EOLA (0.0 control; 0.25; 0.50; 1.0; and 2.0 ml/kg diet). After 45 days of feeding, the fish were infected with Aeromonas spp. followed by a 14‐day period of observation. There was no mortality during growth assessment. The addition of 2.0 ml EOLA/kg diet improved feed conversion ratio and condition factor and increased lysozyme activity and haematocrit (Hct), and decreased plasma globulin levels compared to the control group. The survival of fish infected with Aeromonas spp. was higher in those fed with 2.0 ml EOLA/kg diet than in fish fed with 0.0–0.5 ml EOLA/kg diet. We concluded that the inclusion of 2.0 ml EOLA/kg diet is recommended for Nile tilapia juveniles, because it improved feed conversion, Hct and immunological activity, did not provoke metabolic changes, and increased survival after Aeromonas spp. infection. 相似文献
This study evaluated the efficiency of the drainage system during the larviculture of Lophiosilurus alexandri. Moreover, we assessed the best feeding rate after feed training for juvenile production. The study was performed in three phases over 87 days. In phase 1 (40 days), larvae were fed live food and posteriorly submitted to feed training in two drainage systems: water drained on the surface (DS), and water drained into a tank column (DI). In the second phase (30 days), using only the DS system juveniles were fed a formulated diet at feeding rates, 2, 4, 6 and 8% of body wet weight. In the third phase (17 days), the fish from the second phase were fed until apparent satiation. At the first phase, the animals in the DS system exhibited greater survival rates and growth. The best feeding rate for daily weight gain, specific growth rate (SGR) and mean body weights were similar: 5.57, 5.13 and 5.68% respectively. In the third phase, an increased SGR was observed in the treatment groups that received lower feeding rates in the second phase (2 and 4%), which could indicate a possible compensatory growth rate. 相似文献
The cover image is based on the Research Article Nonanal, a new fall armyworm sex pheromone component, significantly increases the efficacy of pheromone lures by Ahmed M. Saveer et al., https://doi.org/10.1002/ps.7460 . Image Credit: Matt Bertone.
Brazil is the world's largest producer of common beans (Phaseolus vulgaris L.). Drought stress harms the morphological and agronomic traits of beans. This study evaluates the reaction to water deficit in five genotypes of black beans. The experiment was conducted in the IDR-IAPAR-EMATER in Londrina-PR, Brazil. A split-plot design was used, with three replications. The genotypes were included in the subplots and the treatments with or without water deficit in the plots. Water deficit was induced on the pre-flowering stage and maintained for 20 days in the plots submitted to drought stress. For the growth analysis, plants were collected at 35, 54 and 70 days after emergence. At the stage of physiological ripeness, several morphological and yield traits were evaluated. The genotypes IPR Uirapuru and BRS Esplendor can be considered tolerant and used as a tolerant source to water deficit in common bean germplasm banks. The line LP 08-90 has morphological and agronomic adaptations efficient to overcome water deficit's effects, presenting a higher grain yield in both crop conditions, which indicates the success of black beans breeding to deal with water deficit. 相似文献
Structural habitat complexity provided by macrophytes is expected to increase richness and abundance of fish species. However, this topic is rarely investigated simultaneously at different periods of fish development. We sampled fish within macrophyte stands and in non-vegetated areas at floodplain lakes and tested the hypothesis that the presence of macrophytes increases abundance and species richness of fish, in addition to changes in species composition, at different periods of fish development. Our findings demonstrated that, in different period of fish development, the highest values of fish species richness and abundance were found at sites colonised by macrophytes. Similarly, changes in fish species composition were observed between habitats colonised by macrophytes and non-vegetated areas. Therefore, the results demonstrate that macrophyte presence plays an important role in regulating fish community structure at different periods of fish development. 相似文献
Bivalves are important components of freshwater ecosystems; however, they are also one of the most threatened animal groups, especially members of the order Unionida. The main threats to freshwater bivalves are habitat modification and invasive species. Protected areas are a common way to minimize impacts and preserve native species, but they are rarely designated with a focus on freshwater invertebrates.
The main goal of this article was to describe the distribution of freshwater bivalves in the state of Rio de Janeiro, and the relationship between these species and bioclimatic areas, land use and protected areas.
Five native and two invasive bivalve species have been reported in Rio de Janeiro. They occur mainly in bioclimatic areas related to the Paraíba do Sul River and Campista Lowlands. The few records of bivalves inside protected areas are in areas of sustainable use that offer a lower level of protection, and frequently in sympatry with invasive bivalves.
Thus, the established protected areas in Rio de Janeiro are not adequately effective for freshwater bivalve conservation, and some species remain under threat even within them. Freshwater bivalves thus remain largely unprotected in the state.
The development of new protected areas and management plans should consider other faunal groups that are usually ignored, such as freshwater bivalves, to achieve more inclusive and effective protection.
