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51.
京族药用红树林民族植物学知识及现状   总被引:1,自引:0,他引:1  
杜钦  韦文猛  米东清 《广西植物》2016,36(4):405-412
京族是我国唯一的海洋民族,在长期与红树林为伴的生存环境中,积累了丰富的利用红树林植物的民族植物学知识。然而,这些知识至今仍不为外界所知。为掌握京族药用红树林民族植物学知识和现状,该研究采用民族植物学和植物分类学方法,调查京族药用红树林知识中的红树林植物种类,记录其具体药用用途,并分析其生存现状及其中包含的可持续利用红树林植物资源经验。结果表明:共记录到京族药用红树林植物15种隶属于10科,具体药用用途共49种。其中,20种已有报道,29种未见报道;通过京族对红树林药用知识认知程度和依赖程度的调查还表明,京族历史上依赖本民族草医的情形已经基本消失,对红树林医药的依赖性和需求性也在消失。最后,剖析了京族在药用红树林植物选择与采集中的可持续利用经验。该研究结果不仅补充和拓宽了红树林民间药物的利用知识,而且为红树植物资源的管理与可持续利用提供了新视角。  相似文献   
52.
We designed primers for amplifying 11 polymorphic microsatellite loci in the blue manakin, Chiroxiphia caudata, a neotropical passerine bird which inhabits a critically endangered tropical ecosystem, the Brazilian Atlantic forest. Based on genotypes from 24 individuals from a single population, we detected between four and 22 alleles per locus with observed heterozygosities ranging from 0.54 to 0.92. These highly variable loci will be useful for determining levels of population differentiation and assessing the impact of habitat fragmentation on levels of genetic variation in isolated populations of these birds.  相似文献   
53.
Available literature indicates that hurricanes do not generally produce long-term detrimental impacts to unmodified coastal systems and that they often provide net benefits along the U.S. Gulf Coast. While there is normally initial erosion from hurricanes, they also often result in a large influx of inorganic sediments, creating new wetlands and contributing to the maintenance of existing wetlands. The formation of washover deposits is disastrous where cultural development has occurred, but in natural areas these deposits are part of the natural cycle of shoreline development and contribute to habitat diversity and productivity. Abundant rainfall typically associated with hurricanes often results in large increases of sediment and nutrient inputs into coastal estuaries, leading to both short-term and long-term increases in productivity. Rainfall during tropical disturbances accounts for a significant part of total precipitation along the northern gulf. The immediate impact of hurricanes may be to reduce populations of some species but these populations generally recover rapidly. Overall, productivity in natural systems seems to be increased by periodic hurricanes. Hurricane impacts are often severe and long lasting in wetlands that have been modified by human impacts such as semi- or complete impoundments.  相似文献   
54.
This study deals with the synthesis of benzophenone sulfonamides hybrids (131) and screening against urease enzyme in vitro. Studies showed that several synthetic compounds were found to have good urease enzyme inhibitory activity. Compounds 1 (N′-((4′-hydroxyphenyl)(phenyl)methylene)-4′′-nitrobenzenesulfonohydrazide), 2 (N′-((4′-hydroxyphenyl)(phenyl)methylene)-3′′-nitrobenzenesulfonohydrazide), 3 (N′-((4′-hydroxyphenyl)(phenyl)methylene)-4′′-methoxybenzenesulfonohydrazide), 4 (3′′,5′′-dichloro-2′′-hydroxy-N′-((4′-hydroxyphenyl)(phenyl)methylene)benzenesulfonohydrazide), 6 (2′′,4′′-dichloro-N′-((4′-hydroxyphenyl)(phenyl)methylene)benzenesulfonohydrazide), 8 (5-(dimethylamino)-N′-((4-hydroxyphenyl)(phenyl)methylene)naphthalene-1-sulfono hydrazide), 10 (2′′-chloro-N′-((4′-hydroxyphenyl)(phenyl)methylene)benzenesulfonohydrazide), 12 (N′-((4′-hydroxyphenyl)(phenyl)methylene)benzenesulfonohydrazide) have found to be potently active having an IC50 value in the range of 3.90–17.99?µM. These compounds showed superior activity than standard acetohydroxamic acid (IC50?=?29.20?±?1.01?µM). Moreover, in silico studies on most active compounds were also performed to understand the binding interaction of most active compounds with active sites of urease enzyme. Structures of all the synthetic compounds were elucidated by 1H NMR, 13C NMR, EI-MS and FAB-MS spectroscopic techniques.  相似文献   
55.
Question: Can the seed bank play a significant role in the restoration of plant communities of dry acidic dune grassland where fire has destroyed Ulex europaeus scrub? Location: Northern French Atlantic coast. Methods: One year after the fire, the seed bank and vegetation were sampled in 1 m × 1 m plots along three transects from the oldest scrub vegetation towards the grassland. Differences in species richness, seed density and contribution of ecological groups in the seed bank and vegetation along the transects were analysed. Results: Seed density and species richness in the seed bank decreased significantly from the grassland towards the centre of the scrub vegetation; 50% of the seed bank consisted of core species of the target plant community, such as Carex arenaria, Aira praecox, Rumex acetosella and Agrostis capillaris. Seeds of these species were also found in the deeper soil layers beneath the oldest scrub vegetation, indicating that they can be considered to be long‐term persistent. Beneath the youngest scrub vegetation, seeds of rare satellite target species also occurred. However, no target species were established on the burned site after one year, resulting in a large discrepancy between seed bank and vegetation. Conclusions: Although the seeds present in the soil indicate that restoration of the acidic grassland based on the seed bank is possible, additional management actions such as mowing and soil disturbance may be necessary to restrict resprouting of Ulex and to stimulate the germination of seeds of target species in the deeper soil layers.  相似文献   
56.
Climate change is considered as the biggest threat to human health in the 21st century. Sub-Saharan Africa, which is the most-at-risk region of the world, is estimated to have a disproportionately large share of the burden of climate change–induced environmental and human health risks. To develop effective adaptations to protect public health, it is essential to consider how individuals perceive and understand the risks, and how they might be willing to change their behaviors in response to them. Using a cross-sectional survey of 1253 individuals in coastal Tanzania we analyzed the relationship between subjective health status (self-reported health) and objective health status on the one hand and perceived health risks of climate change. Generally, higher subjective health status was associated with lower scores on perceived health risks of climate change. Concerning objective health status, the results were varied. Individuals who affirmed that they had been previously diagnosed with hepatitis, skin conditions, or tuberculosis had lower scores on perceived health risks of climate change, unlike their counterparts who affirmed that they had been previously diagnosed with malaria in the past 12 months or had been diagnosed with HIV/AIDS. These relationships persist even when biosocial and sociocultural attributes are taken into consideration. The results underscore the complex ways in which objective and subjective health interact with both biosocial and sociocultural factors to shape perceived health risks of climate change.  相似文献   
57.
Sewage pollution is a worldwide concern and can result in increasing levels of trace elements in the environment that can pose serious risks both to wildlife and human health. This highlights the importance of studying the role of sewage discharges in the contamination of aquatic systems, especially in rocky shores, since part of our food resources is directly collected from coastal waters. For this purpose, the accumulation of trace elements (Cu, Zn, Pb, Ni, Co, Cd, Fe, Mn, and As) by edible molluscs (Mytilus galloprovincialis, Patella ulyssiponensis, and Phorcus lineatus) was compared between one sewage-impacted area and two reference areas.

This study suggests that the concentrations of trace elements in the soft tissues of the selected molluscs can be affected by the presence of sewage discharges, and that limpets seem to be the best bioindicator. Moreover, the sewage pollution increased the concentrations of As in the mollusc species, emphasizing its potential damaging effects on natural systems and on edible species.  相似文献   

58.
Phylogeographic patterns in Macrodon ancylodon sampled from 12 locations across all its range were investigated using mitochondrial DNA cytochrome b sequences, and analysed together with patterns of morphometric differentiation. Populations of the North Brazil and the Brazil currents, with warmer waters, form a clade (tropical clade) separated by 23 fixed mutations from the populations that inhabit regions of colder waters influenced by the Brazil and Malvinas currents (subtropical clade). No gene flow exists between the tropical and subtropical clades, and most likely also between the two groups of the tropical clade. Distribution of these clades and groups is correlated with flow of currents and their temperatures, and is facilitated by larval retention and low adult migration. Despite differentiation at the molecular level, fishes analysed from all these current-influenced regions are morphometrically homogeneous. Throughout its range M. ancylodon inhabits the same, or very similar niche; thus, stabilizing selection probably promotes the retention of highly conserved morphology despite deep genetic divergence at the mitochondrial DNA cytochrome b.  相似文献   
59.
Along the east coast of North Kurils, the egg deposits of Careproctus snailfishes (Scorpaeniformes: Liparidae) were revealed in the gill cavity of 9.9% of all golden king crabs, mostly in individuals with carapace of 61–80 mm width (61.6%). The number of Careproctus eggs in the gill cavity of crabs increased with the increase of the carapace width. In fact, 97.0% of the crabs had such egg deposits only at one side of their carapaces. Most of the egg deposits, apparently, belonged to C. cypsellurus and C. furcellus. The number of crabs with egg deposits was related to the number of post-molt individuals. Evidently, egg depositing by Careproctus snailfishes out of the gill cavity of crabs is a rather widespread phenomenon.  相似文献   
60.
AIMS: This paper evaluates the presence of human pathogen micro-organisms in marine sediments in a coastal area suitable for bathing. In addition, the grain size analysis was performed in order to correlate the characteristics of the sediments and the microbial content. METHODS AND RESULTS: The samples were collected in two small bays along the central Adriatic coast, where breakwaters had been built for the purpose of halting marine erosion. Faecal contamination indicators, Salmonella and Vibrio species, enteric viruses were investigated using standard techniques for isolation and identification. The grain size was determined using calibrated sieves and 'Sedigraph' device. In some samples, the faecal contamination indices overstepped legislative limits. Salmonella was never found. Vibrio and enteric viruses were isolated: the micro-organisms were preferentially abundant in fine sediments. CONCLUSIONs: Marine sediments can represent an important reservoir of allochthonous and marine micro-organisms and the microbial charge correlates with the characteristics of the sediments. SIGNIFICANCE AND IMPACT OF THE STUDY: This study indicates that it is important to analyse marine sediments before defining the quality of coastal areas.  相似文献   
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