Applying ecological niche modelling to plan conservation actions for the Red-spectacled Amazon (Amazona pretrei)     

Miguel Ângelo Marini  Morgane Barbet-Massin 《Biological conservation》2010,143(1):102-112

The Red-spectacled Amazon (Amazona pretrei) is an endangered, small range and migratory parrot threatened by habitat destruction and pet trade. We modelled its geographical distribution with the objective of predicting its historical, current and future (in face of climatic changes) geographical distributions. We also tested the assumption that the species tracks similar ecological conditions while seasonally migrating. Finally, we estimated the overlap between its predicted distributions and the current protected areas network. We used eight modelling techniques in an ensemble-forecasting approach to reach consensus distributional scenarios. The modelled historical breeding and wintering ranges covered a larger area than today. Its current year-round distribution is located in the same region as before but decreased by 13%, whereas the breeding range decreased by 32%, and the wintering range by 43%. The future year-round distribution is predicted to decrease by 47% and shift to east by 2060. Even more drastic decreases in range are predicted for breeding (63%) and wintering (91%) ranges. The niches of the breeding and wintering distributions are good predictors of the records of the other season. The greatest variation (SDs) in the predictions comes from modelling tools and GCMs, and little from climatic scenarios. However, variation in predictions were small within high probability regions for modelling tools by higher everywhere for GCMs and climatic scenarios. The Red-spectacled Amazon is currently underrepresented (<1% of year-round range, and <4% of each seasonal range) in the current reserve system. A broad view over all estimated and predicted ranges revealed that a small portion of the range has a very important role in current and future conservation actions for this bird - in the northeast part of state of Rio Grande do Sul and southeast state of Santa Catarina, Brazil.  相似文献   

Growth and mortality of common octopus Octopus vulgaris reared at different stocking densities in Mediterranean offshore cages     

Benjamín García García  Jesús Cerezo Valverde  Felipe Aguado-Giménez  José García García  & María D Hernández 《Aquaculture Research》2009,40(10):1202-1212

Four ongrowing cycles of common octopus ( Octopus vulgaris ), each with two stocking densities, were carried out in an offshore area in order to evaluate the effect of the following variables on growth ( G , % body weight day⁻¹) and mortality ( M , % day⁻¹): weight ( W , 0.5–3.0 kg), temperature ( T , 14–26 °C), stocking density (SD, 6–46 kg m⁻³), size dispersion, expressed as coefficient of variation (CV, 13–42%) and significant wave height (SWH: 0.4–1.2 m). The assays were performed in an 8 m³ stainless-steel floating cage divided into two compartments of 4 m³ each. For the range of temperatures considered (14–26 °C), G depended significantly on T and SWH, with maximum G values being obtained at 18.5 °C and with an important negative effect of SWH. M depended significantly on T, W and CV, mortality being minimal at 18 °C. The two other variables had an antagonistic effect, mortality increasing with greater size dispersion – suggesting that animals should be graded throughout the process – although the effect diminished as the sizes increased. The results point towards two alternatives for the commercial ongrowing of octopus under the particular conditions of the present study: (A) two ongrowing cycles of 3.5 months to reach a final weight of 2.5 kg or (B) one 5-month cycle to reach a final weight of 3.5 kg.  相似文献   

Exploring Chemical Diversity of Phorbas Sponges as a Source of Novel Lead Compounds in Drug Discovery     

Alessia Caso  Fernanda Barbosa da Silva  Germana Esposito  Roberta Teta  Gerardo Della Sala  Laura P. A. Nunes Cavalcanti  Alessandra Leda Valverde  Roberto Carlos C. Martins  Valeria Costantino 《Marine drugs》2021,19(12)

Porifera, commonly referred to as marine sponges, are acknowledged as major producers of marine natural products (MNPs). Sponges of the genus Phorbas have attracted much attention over the years. They are widespread in all continents, and several structurally unique compounds have been identified from this species. Terpenes, mainly sesterterpenoids, are the major secondary metabolites isolated from Phorbas species, even though several alkaloids and steroids have also been reported. Many of these compounds have presented interesting biological activities. Particularly, Phorbas sponges have been demonstrated to be a source of cytotoxic metabolites. In addition, MNPs exhibiting cytostatic, antimicrobial, and anti-inflammatory activities have been isolated and structurally characterized. This review provides an overview of almost 130 secondary metabolites from Phorbas sponges and their biological activities, and it covers the literature since the first study published in 1993 until November 2021, including approximately 60 records. The synthetic routes to the most interesting compounds are briefly outlined.  相似文献   

The role of pendimethalin in the integrated management of propanil-resistant Echinochloa colona in Central America     

Charles R. Riches  Julia S. Knights  Lilliana Chaves  John C. Caseley  Bernal E. Valverde 《Pest management science》1997,51(3):341-346

Pre-emergence activity of pendimethalin on propanil-resistant jungle rice (Echinochloa colona) was demonstrated in glasshouse trials. Both susceptible and resistant populations, collected from Costa Rica, were controlled by 1·25 kg ha^-1, the usual application rate used in the field where Rottboellia cochinchinensis is also a problem. When applied post-emergence, propanil performance was improved by the addition of low doses of pendimethalin to the herbicide mixture. A propanil-resistant selection was controlled by 0·23 kg ha^-1 pendi-methalin+0·54 kg ha^-1 propanil at the one-to-two leaf stage, and 0·23 kg ha^-1 pendimethalin+1·08 kg propanil at the three-to-four leaf stage compared to 1·08 kg and 2·16 kg ha^-1 respectively when propanil was applied alone. This suggests that pendimethalin improves post-emergence control in the field compared to the standard propanil treatment and can provide residual pre-emergence control of late-germinating individuals, so reducing the propanil selection pressure. For effective jungle rice control, growers apply propanil (3·84 kg ha^-1) at 10 and 20 days after planting (DAP) followed by one application of fenoxaprop-P-ethyl (0·045 kg ha^-1) at 35 DAP. Field experiments, conducted in dry-seeded upland rice in southern Costa Rica, demonstrated that under high jungle-rice population pressure, one application of pendimethalin at 1·5 kg ha^-1 provided an effective replacement for propanil, resulting in reduced weed-control costs. ©1997 SCI  相似文献