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31.
Habitat enhancement for birds is frequently implemented during mine site restoration. Cliff‐nesting birds often colonize anthropogenic environments such as mining areas (aggregate sites and quarries for aggregate and cement production). Mining activity can compromise breeding success, causing cliff‐nesting birds to depend on the management and restoration of mining areas. The objective of our study is to assess the importance of mine site habitats for Sand Martin conservation and reconcile mining activity with breeding success in Mediterranean environments. We studied Sand Martin breeding habitat preferences in mining areas at three spatial scales. At the mining site scale, we compared 10 mining sites with Sand Martin burrows with 19 mining sites without burrows. At the colony scale (vertical structures with colonies), we evaluated the relationships between the number of breeding pairs, number of burrows, and colony characteristics within 30 distinct Sand Martin colonies. At the burrow scale, we compared the characteristics of the available vertical structure with the areas used by Sand Martins. At the mining site scale, Sand Martins preferred more surface of water bodies, shorter distances to flowing water, older sites, and mining sites which produce aggregates instead of cement. At the colony scale, Sand Martins preferred southwest orientations and stockpiles to vertical extraction faces. At the burrow scale, birds preferred the most vertical areas of the face. Our results support the need for effective habitat restoration and improved management for more effective Sand Martin conservation within mining areas. Simple interventions can enhance habitat quality and conservation of cliff‐nesting birds.  相似文献   
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The understanding of global diversity patterns has benefitted from a focus on functional traits and how they relate to variation in environmental conditions among assemblages. Distant communities in similar environments often share characteristics, and for tropical forest mammals, this functional trait convergence has been demonstrated at coarse scales (110–200 km resolution), but less is known about how these patterns manifest at fine scales, where local processes (e.g. habitat features and anthropogenic activities) and biotic interactions occur. Here, we used standardized camera trapping data and a novel analytical method that accounts for imperfect detection to assess how the functional composition of terrestrial mammal communities for two traits – trophic guild and body mass – varies across 16 protected areas in tropical forests and three continents, in relation to the extent of protected habitat and anthropogenic pressures. We found that despite their taxonomic differences, communities generally have a consistent trophic guild composition, and respond similarly to these factors. Insectivores were found to be sensitive to the size of protected habitat and surrounding human population density. Body mass distribution varied little among communities both in terms of central tendency and spread, and interestingly, community average body mass declined with proximity to human settlements. Results indicate predicted trait convergence among assemblages at the coarse scale reflects consistent functional composition among communities at the local scale, suggesting that broadly similar habitats and selective pressures shaped communities with similar trophic strategies and responses to drivers of change. These similarities provide a foundation for assessing assemblages under anthropogenic threats and sharing conservation measures.  相似文献   
34.
The tomato (Solanum lycopersicum L.) is one of the world’s most important vegetable crops. Still, phytopathogenic bacteria affect the yield and quality of tomato cultivation, like Agrobacterium tumefeciens (At), Clavibacter michiganensis subsp. michiganensis (Cmm), Pseudomonas syringae pv. tomato (Pst), Ralstonia solanacearum (Rs), and Xanthomonas axonopodis (Xa). Synthetic chemical products are used mostly on disease plant control, but overuse generates resistance to bacterial control. This study aimed to evaluate the in vitro antibacterial activity of the ethanolic extract of Moringa oleifera Lam. leaves against At, Cmm, Pst, Rs, and Xa, as well as information about this plant species’ chemical composition. Antibacterial activity against pathogens observed by microplate technique, phytochemical screening, and FTIR analysis revealed different bio-active compounds on ethanolic extracts with antibacterial activity. The growth inhibition rate ranged between 0.08% and 99.94%. The inhibitory concentration, IC50, required to inhibit 50% of At, Cmm, Pst, Rs, and Xa bacterial growth, was 276.67, 350.48, 277.85, 351.49, and 283.22 mg/L, respectively. Inhibition of phytopathogen bacteria’s growth increased as the concentrations of the extract also increased. Moringa oleifera extract can be recommended as a potent bio-bactericide.  相似文献   
35.
Chickpea contains high levels of protein, vitamins and minerals. Acceptable chickpea yield is the result of meeting nitrogen and phosphorus requirements. The effect of appropriately meeting such requirements reflects on growth and can easily be evaluated using growth analysis. This research determined: (a) The effect of nitrogen and phosphorus fertilization on phenology, net assimilation rate, number of green leaves, leaf area, leaf area index and leaf area duration; (b) Green chickpea yield and number of pods due to fertilization; and (c) The combination of nitrogen and phosphorus fertilization that yields the most net revenue. Nitrogen and phosphorus fertilization was evaluated; each at the doses of 0, 75 and 150 kg ha–1 (N0, N75, N150; P0, P75 and P150, respectively). The combination of the levels of both nutrients generated nine combinations of treatments which were distributed in the field in a randomized complete block design in an arrangement of divided plots with four repetitions. Timing of phenological phases were similar among treatments. Nitrogen and phosphorus fertilization increased number of leaves, leaf area index, and leaf area duration that translated into increased green chickpea yield (GCY). Combinations N150-P75 and N150-P150 produced the highest GCY. The highest net revenue and revenue per peso invested was obtained with N150-P75.  相似文献   
36.
Abstract

This study proposes a bioclimatic characterization and a new biogeographic division for the Antarctic territories up to the province level following the criteria and models of Rivas-Martínez et al. The Antarctic Kingdom comprises the continent of Antarctica, the surrounding ice-covered Antarctic islands, and the associated cold oceanic islands and archipelagos. It has two biogeographic regions: the Antarctic Region and the Subantarctic Insular Region. The Antarctic Region includes the entire pergelid Antarctic continent and the surrounding islands and archipelagos, and is characterized by upper suprapolar hyperoceanic and oceanic or Polar pergelid bioclimates on the coasts. The region has been divided into three pr6ovinces: Maritime Antarctica, West Antarctica and East Antarctica. The Subantarctic Insular Region comprises the circumantarctic islands and archipelagos that are widespread at the southern tip of the planet’s most important oceans, mostly in the subtemperate latitudinal zone inside or not far from the Antarctic Convergence. Bioclimatically, all insular subantarctic territories (excluding the South-American Tierra de Fuego, Terra Magellanica and large islands) are characterized by thermo-suprapolar and semipolar antarctic hyperoceanic bioclimates on the coasts. Four provinces – Falklandian-South Georgian, Kerguelenian, Macquarian and Aucklandian-Campbellian – have been recognized in this region. All these units are characterized by floristic bioindicators.  相似文献   
37.
Geckos of the genus Trigonodactylus are widely distributed in the sand deserts of the Arabian Peninsula. Three species of this genus are currently recognized, with a fourth one, Stenodactylus pulcher, which placement within Trigonodactylus has been tentatively suggested, but not yet confirmed. We present a phylogenetic analysis of the genus Trigonodactylus with new specimens collected in central Saudi Arabia and southern Jordan. New genetic data has been generated from three mitochondrial markers to investigate the phylogenetic relationships of all species of the genus and to assess the putative generic assignment of S. pulcher. Our results confirm that S. pulcher indeed belongs within Trigonodactylus, branching as a sister lineage to all other species of the genus. The new samples cluster within Trigonodactylus arabicus, thus confirming the genetic homogeneity of the species across its large and seemingly inhospitable range. The new specimen collected in southern Jordan represents the first record for the country and a considerable range extension to the northwest from all previously reported localities. Our findings and discovery of a new species for Jordan highlight the need of more field surveys to be carried out in the underexplored parts of Jordan and northern Saudi Arabia, as these places still hold a potential for new discoveries and are crucial for understating the biogeography of the Arabian herpetofauna.  相似文献   
38.
Red sanders (Pterocarpus santalinus L.) is an endangered and endemic tropical tree species from India in need of restoration. This study evaluated options for improving establishment of its advance regeneration in degraded forests. Using randomized complete block design, the effect of silvicultural treatments involving prescribed fire, in combination with disking, singling, disking with singling, and control (no treatment) on survival and growth of advanced regeneration were evaluated for a period of 2 years. Results indicate that the treatments served to ameliorate microsite conditions resulting in better survival and growth. Seedlings with fewer coppice shoots, treatments with a singling component, and treatments with disking component showed better survival and growth. The number and height of other neighboring seedlings and trees also influenced seedling establishment. Seedlings showed significantly higher survival results in the prescribed fire with disking (disking with prescribed burn [DPB]: 96%) and prescribed fires with disking and singling (singling plus disking with prescribed burn [SDPB]: 94%) treatments. Similarly, tall seedlings and those with larger root collar diameters accrued significantly higher volume growth in DPB (87%) and SDPB (97%) treatments. Although seedlings showed similar increments in DPB and SDPB treatments, better survival due to singling indicated the latter as the best option. In dense regeneration areas, preferential treatment of the taller and larger stump‐sized seedlings and, in limited regeneration areas that of smaller seedlings, may yield better results. Additionally, removal of competing vegetation and canopy opening may also help establishment of young regeneration. The results of this study have applications for restoration of endangered species in other tropical dry deciduous ecosystems worldwide.  相似文献   
39.
This quantitative study examined access to school music instruction with regard to race in two urban areas: Detroit, Michigan, and Washington, DC, in 2009–2010. We found significant differences in the provision of music instruction between schools with high and low proportions of nonwhite enrollment, in categories including curricular offerings, extracurricular offerings, and resources. In the Detroit area, only 31 percent to 60 percent of schools with high percentages of nonwhite students offered any music instruction at all. We contrast our findings with those of a National Center for Educational Statistics report to demonstrate how regional and national averages can obscure information that should guide policy, such as the influence of location and racial demographics of schools on the provision of public school music instruction. The article concludes with a discussion of the implications of using flawed data in the creation of policy and suggestions for more comprehensive and accurate data collection and analysis.  相似文献   
40.
A recent molecular phylogeny of the Arid clade of the genus Hemidactylus revealed that the recently described H. saba and two unnamed Hemidactylus species from Sinai, Saudi Arabia and Yemen form a well-supported monophyletic group within the Arabian radiation of the genus. The name ‘Hemidactylus saba species group’ is suggested for this clade. According to the results of morphological comparisons and the molecular analyses using two mitochondrial (12S and cytb) and four nuclear (cmos, mc1r, rag1, rag2) genes, the name Hemidactylus granosus Heyden, 1827 is resurrected from the synonymy of H. turcicus for the Sinai and Saudi Arabian species. The third species of this group from Yemen is described formally as a new species H. ulii sp. n. The phylogenetic relationships of the members of ‘Hemidactylus saba species group’ are evaluated and the distribution and ecology of individual species are discussed.  相似文献   
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