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101.
Context
Species are expected to shift their distributions in response to global environmental changes and additional protected areas are needed to encompass the corresponding changes in the distributions of their habitats. Conservation policies are likely to become obsolete unless they integrate the potential impacts of climate and land-use change on biodiversity.Objectives
We identify conservation priority areas for current and future projected distributions of Iberian bird species. We then investigate the extent to which global change informed priority areas are: (i) covered by existing protected area networks (national protected areas and Natura 2000); (ii) threatened by agricultural or urban land-use changes.Methods
We use outputs of species distributions models fitted with climatic data as inputs in spatial prioritization tools to identify conservation priority areas for 168 bird species. We use projections of land-use change to then discriminate between threatened and non-threatened priority areas.Results
19% of the priority areas for birds are covered by national protected areas and 23% are covered by Natura 2000 sites. The spatial mismatch between protected area networks and priority areas for birds is projected to increase with climate change. But there are opportunities to improve the protection of birds under climate change, as half of the priority areas are currently neither protected nor in conflict with urban or agricultural land-uses.Conclusions
We identify critical areas for bird conservation both under current and climate change conditions, and propose that they could guide the establishment of new conservation areas across the Iberian Peninsula complementing existing protected areas.102.
Anneli Poska Vivika Väli Pille Tomson Jüri Vassiljev Kersti Kihno Tiiu Alliksaar Miguel Villoslada Leili Saarse Kalev Sepp 《Landscape Ecology》2018,33(4):529-546
Context
Anthropogenic and environmental changes are reshaping landscapes across the globe. In this context, understanding the patterns, drivers, and consequences of these changes is one of the central challenges of humankind.Purpose
We aim to test the possibilities of combining modern multidisciplinary approaches to reconstruct the land-cover and linking the changes in land-cover to socioeconomic shifts in southern Estonia over the last 200 years.Methods
The historical records from five, and maps from six time periods and 79 pollen-based land-cover reconstructions from four lakes are used to determine the land-cover structure and composition and are thereafter combined with the literature based analyses of socioeconomic changes.Results
All information sources recorded similar changes in the land-cover. The anthropogenic deforestation was comparable to today’s (approximately 50%) during the nineteenth century. Major political and socioeconomic changes led to the intensification of agriculture and maximal deforestation (60–85%) at the beginning of the twentieth century. The land nationalisation following the Soviet occupation led to the reforestation of the less productive agricultural lands. This trend continued until the implementation of European Union agrarian subsidies at the beginning of the twenty first century.Conclusions
Pollen-based reconstructions provide a trustworthy alternative to historical records and maps. Accounting for source specific biases is essential when dealing with any data source. The landscape’s response to socioeconomic changes was considerable in Estonia over the last 200 years. Changes in land ownership and the global agricultural market are major drivers in determining the strength and direction of the land-cover change.103.
María?C.?Mateo-SánchezEmail author Aitor?Gastón Carlos?Ciudad Juan?I.?García-Vi?as Jorge?Cuevas César?López-Leiva Alfredo?Fernández-Landa Nur?Algeet-Abarquero Miguel?Marchamalo Marie-Josée?Fortin Santiago?Saura 《Landscape Ecology》2016,31(6):1261-1276
Context
Multi-scale approaches to habitat modeling have been shown to provide more accurate understanding and predictions of species-habitat associations. It remains however unexplored how spatial and temporal variations in habitat use may affect multi-scale habitat modeling.Objectives
We aimed at assessing how seasonal and temporal differences in species habitat use and distribution impact operational scales, variable influence, habitat suitability spatial patterns, and performance of multi-scale models.Methods
We evaluated the environmental factors driving brown bear habitat relationships in the Cantabrian Range (Spain) based on species presence records (ground observations) for the period 2000–2010, LiDAR data on forest structure, and seasonal estimates of foraging resources. We separately developed multi-scale habitat models for (i) each season (spring, summer, fall and winter) (ii) two sub-periods with different population status: 2000–2004 (with brown bear distribution restricted to the main population nuclei) and 2005–2010 (with expanding bear population and range); and (iii) the entire 2000–2010 period.Results
Scales of effect remained considerably stable across seasonal and temporal variations, but not the influence of certain environmental variables. The predictive ability of multi-scale models was lower in the seasons or periods in which populations used larger areas and a broader variety of environmental conditions. Seasonal estimates of foraging resources, together with LiDAR data, appeared to improve the performance of multi-scale habitat models.Conclusions
We highlight that the understanding of multi-scale behavioral responses of species to spatial patterns that continually shift over time may be essential to unravel habitat relationships and produce reliable estimates of species distributions.104.
Torés Juan Antonio González María Dolores Pozo Eva Urdiales José Luis Medina Miguel Ángel Sánchez-Jiménez Francisca 《Phytoparasitica》1999,27(3):207-213
Chlorpheniramine (CPA) is an antihistaminic that changes the conformation of DNA and inhibits polyamine biosynthesis in mammalian
cells. In the present work, we tested the effect of CPA on four genera of fungi species (Altemaria alternata, Botrytis cinerea, Cladosporium cladosporioides and threePenicillium spp.) grownin vitro. Similar growth inhibitions of these genera were produced by 0.5 raM iprodione, CPA and histidinol, but CPA was the most effective.
The CPA sensitivities of the twoB. cinerea strains were different. Putrescine did not restore the fungal growth inhibited by CPA. 相似文献
105.
Fernando Nuez Belén Picó Adriana Iglesias Juan Esteva Miguel Juarez 《European journal of plant pathology / European Foundation for Plant Pathology》1999,105(5):453-464
The Melon yellows virus (MYV), a whitefly-transmitted closterovirus, is one of the major pathogens causing crop losses in protected melons in southeastern Spain. An accession of the wild Asiatic Cucumis melo ssp. agrestis (Cma) shows resistance to MYV infection. Results indicate the participation of two resistance mechanisms in this source: firstly, an antixenotic reaction against Trialeurodes vaporariorum, the disease vector, and secondly, resistance to the virus. The combined effect of these two mechanisms confers Cma a higher level of resistance, expressed as a delayed and milder infection.The genetics of resistance to the Melon yellows closterovirus have been studied in two families derived from Cma. As under natural infection conditions, the effect of antixenosis and virus resistance cannot be distinguished, a biometrical model that permits separation of the two resistance mechanisms operating in the same resistant source, has been proposed to determine genetic control of MYV resistance.The genetic analysis has been conducted by fitting the disease progress curves of each generation to the biometrical model instead of fitting the final disease ratios. The scoring of disease incidence over time allows for the comparison of data from assays conducted in different conditions (2 years/4 transplanting dates), thus reinforcing the analysis.The results agree with a simple control of the resistance to MYV derived from Cma, with incomplete penetrance of the gene and partial dominance of resistance. The effect of antixenosis on the spread of this plant virus is highly significant in Cma, but not in segregant generations.Since there do not exist crossability barriers between this accession and the cultivated melon, Cma could be readily used in breeding programmes to obtain melon varieties resistant to MYV. 相似文献
106.
107.
Rita Constantino Miguel B. Gaspar Fábio Pereira Susana Carvalho João Cúrdia Domitília Matias Carlos C. Monteiro 《水产资源保护:海洋与淡水生态系统》2009,19(5):542-553
- 1. Razor clams are found in different habitats ranging from sheltered systems (e.g. lagoons and estuaries) to open coasts. They are distributed worldwide and comprise a small number of species of high economic value. Depending on the specific habitat and species exploited, different mechanical and hand‐harvesting techniques are employed. While the environmental effects resulting from mechanized methods have been described by several authors, the impacts caused by traditional hand‐harvesting methods remain unknown. Therefore, a study was undertaken in Ria Formosa lagoon (South of Portugal) addressing the environmental effects resulting from harvesting Solen marginatus with salt.
- 2. No significant impact on the sediment was found; the main effect was an increase in salinity after covering the area with salt, which decreased rapidly with the flood tide and after a few hours had returned to pre‐harvesting levels.
- 3. No effects on benthic communities were observed, with similar fluctuation patterns recorded in control and experimental areas, the observed differences being attributed to the natural variability of benthic populations.
- 4. Based on the results obtained in the present study, a razor clam fishery using salt in intertidal areas can be considered environmentally ‘friendly’.
108.
Histological alterations in gills of shrimp Litopenaeus vannamei in low‐salinity waters under different stocking densities: Potential relationship with nitrogen compounds 
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下载免费PDF全文 Marcela G. Fregoso‐López María S. Morales‐Covarrubias Miguel A Franco‐Nava Javier Ramírez‐Rochín Juan F Fierro‐Sañudo Jesús T Ponce‐Palafox Federico Páez‐Osuna 《Aquaculture Research》2017,48(12):5854-5863
Two experimental modules with different stocking densities (M1 = 70 and M2 = 120 shrimp /m2) were examined weekly over a culture cycle in tanks with low‐salinity water (1.9 g/L) and zero water exchange. Results showed survival rates of 87.7 and 11.9% in M1 and M2, respectively. Water temperature, pH, dissolved oxygen, electrical conductivity and chlorophyll a were not significantly (p > .05) different between modules. In contrast, the concentrations of nitrogen compounds were significantly (p < .05) different between modules, except nitrite‐N (M2 were 2.31 ± 1.38 mg/L N‐TAN, 0.18 ± 0.49 mg/L N‐NO2? and 6.83 ± 6.52 mg/L N‐NO3?; in M1: 0.97 ± 0.73 mg/L N‐TAN, 0.05 ± 0.21 mg/L N‐NO2? and 0.63 ± 0.70 mg/L N‐NO3?). When waters of both modules reached higher levels of ammonia and nitrite, histological alterations were observed in gills. The histological alterations index (HAI) was higher in M2 (5‐112) than in M1 (2‐22). 相似文献
109.
110.
Enrique Cervantes‐Santiago Martha P. Hernández‐Vergara Carlos I. Pérez‐Rostro Miguel A. Olvera‐Novoa 《Aquaculture Research》2010,41(9):e62-e71
The influence of dietary protein/lipid levels on growth and survival in juvenile crayfish (Procambarus acanthophorus) was evaluated during a 12‐week nutritional trial. Twenty experimental diets were formulated containing different protein (200, 250, 300, 350 and 400 g kg?1) and lipid (60, 80, 100 and 120 g kg?1) levels. A bifactorial model (5 × 4) was used with three replicates and 15 crayfish (0.014±0.006 g) per replicate, in a recirculation system with 60–15 L rectangular tanks and a biological filter, the culture conditions were a photoperiod of 12:12 h L:D and temperature 24.7±1.0 °C. Total survival ranged from 66.6% to 86.6%, with no differences attributed to treatments. Dietary protein levels had a significant effect on growth gain and nutritional efficiency; in contrast, lipid levels had no effect on juvenile performance. The 250/120 (protein/lipid) treatment promoted the most efficient growth (final weight: 3.09 g, weight gain: 21 995%, specific growth rate: 3.35% day?1); the less efficient growth was observed in juveniles fed with 400 g kg?1 protein diets. The quadratic regression model indicated 279 g kg?1 as the optimal protein level for crayfish growth, while levels between 211 and 232 g kg?1 could minimize the feeding costs without affecting growth. 相似文献