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1.
World over the traditional knowledge has always formed the foundation for development of modern medicines as a result of scientific follow up of the traditional knowledge. Andaman archipelago represents one of the greatest emporia of ethno botanical wealth in India where aboriginal native tribes of ancient culture remain in their virginity and possess abundant ethnic knowledge. The Jarawas of Andaman Island are one such primitive and dwindling community. Jarawas inhabit the Jarawa Reserve located along the western parts of the South and Middle Andamans. A brief account of anthropology of the tribe is given. Results of ethnobotanical studies of Jarawa tribe have been enumerated which revealed interesting plants which can be further prioritized for scientific evaluation and Bioprospection for product development. The species like Alpinia manii, Amomum aculeatum, belonging to Zingiberaceae and Pseuduvaria prainii, Orophea katschallica of Annonaceae are shown to have effective insect and bee repellent properties. Such leads should be subjected to further scientific scrutiny for development of global level products having mosquito and other disease causing insect repellent properties. While this achieves the human welfare aspects, at the same time boosts the economy of the region. The Jarawas possess extensive knowledge of the plants of the surrounding forests and use them in their daily life for food, medicine, shelter, fibres, ornaments, bows and arrows and for many other needs. Such plants are enumerated with correct botanical names, family, Jarawa names, plant parts used along with details of use.  相似文献   

2.
The Banyang-Mbo Wildlife Sanctuary, an area of lowland tropical rainforest in southwestern Cameroon, was designed by the Government of Cameroon specifically to protect 10 species and one order (Chelonia) of wildlife including some of the most endangered primates in Central and West Africa such as the drill (Mandrillus leucophaeus) and chimpanzee (Pan troglodytes). The long-settled local communities surrounding the Sanctuary maintain user rights of the forest and its natural resources as long as the conservation goals of the protected area are not compromised. A three-year study assessed local communities’ hunting dynamics in and around the sanctuary. Ten village-based assistants weighed, sexed, and aged all animal carcasses harvested by the 96 hunters participating in the study from June 1999 to March 2002. Data on weapon type, use of meat, location of kill, and price for each killed animal were also collected. We compare bushmeat dynamics and hunting cultures of two tribes living on the periphery of the Sanctuary, the Banyangi and the Mbo. A total of 13 489 animals were harvested during the study period, 4656 by Banyangi and 8833 by Mbo. Our results suggest that the condition of bushmeat when sold by hunters, either fresh or smoked, does not appear to affect the price. Bushmeat was significantly cheaper than the alternative sources of protein available in the nearest town. Although both tribes appear to use similar weapon technologies and hunting techniques, they differ with respect to amounts harvested and bushmeat use. The tribe settled deep in the forest with no road access hunts more intensively and for commercial sale outside the region, while the tribe along the road consumes or sells most of their catch locally.  相似文献   

3.
Since the 1800s, brocket deer have been an important source of meat and income for subsistence and professional hunters in the Peruvian Amazon. Today, local people continue to hunt brocket deer for subsistence meat and for sale in local meat markets. Although brocket deer are not hunted as frequently as peccaries, they make a significant contribution to rural household economies. This study assessed the sustainability of hunting of brocket deer by local communities in the Tamshiyacu Tahuayo Communal Reserve (TTCR), northeastern Peru. We analyzed data from 1991 to 1999 using density comparisons, hunting pressures, an age structure model, and a harvest model comparing results between heavily hunted, slightly hunted, and non-hunted sites. The four approaches agreed that brocket deer are harvested sustainably. The sustainability of brocket deer hunting will depend on the continued presence of other valuable wildlife species (e.g. peccaries and large rodents), which are more preferred due to their ease of hunting and higher rates of encounters. Gross productivity indicates that brocket deer are showing resilience in the form of density dependent reproductive adjustments in the TTCR, but they may still be vulnerable to overhunting. Consequently, current levels of harvesting may be continued until further ecological and biological information on the species' population trends assist in defining more reliable sustainable offtake levels.  相似文献   

4.
Movement of people from third- to first-world countries frequently brings with it different, and often opposing, approaches to wildlife. About 22,000 Thai workers are currently employed in Israel, mostly in agriculture. Most of these workers originate from the poor Isaan region in northeast Thailand, where the major source of income is from agriculture, supplemented by gathering and hunting of animals. In Israel, many of them engage in illegal hunting and gathering of wildlife. At least 28 species of mammals (including six domestic ones), 25 species of birds, seven species of reptiles, three species of amphibians and various species of fish, molluscs and other invertebrates have been found mainly in traps (chiefly noose traps) laid by Thai workers. Other methods of capture used by the workers include the use of hand-held catapults, netting, the collection of bird eggs, and the gathering of slow-moving vertebrates and invertebrates. These activities have a serious deleterious effect on the wildlife in Israel.  相似文献   

5.
Hawksbill Sea-turtles once occurred in vast numbers around Madagascar but persistent intensive exploitation has led to a drastic reduction in their population. Traditional hunting methods, employing harpoon, net, and grapnel, are still in use, though Remora fishing is no longer widely practised. Although reduced, the current value of Hawksbill products is still substantial, and justifies rigorous enforcement of the adequate existing laws. The present population is such that, with some protection, it should prove possible to restore numbers to a safer level.  相似文献   

6.
7.
基于NPP/VIIRS夜光遥感影像的作业灯光围网渔船识别   总被引:1,自引:0,他引:1  
为对远洋灯光渔船作业信息进行实时动态监测,该研究基于可见光红外辐射仪(visible infrared imaging radiometer suite,VIIRS)夜光遥感影像,根据远洋灯光渔船作业时其集鱼灯灯光在VIIRS白天/夜晚波段(day/night band,DNB)影像上的辐射特征,采用峰值中值指数(spike median index,SMI)对灯光渔船与背景像元间的辐射差异进行拉伸,在此基础上设计了基于最大熵法(maximum entropy method,Max Ent)阈值分割以及局部峰值检测(local spike detection,LSD)的作业远洋灯光渔船识别算法,并采用2015年西北太平洋公海灯光围网渔场内作业渔船船位监控系统(vessel monitoring system,VMS)数据对该算法的识别精度进行检验。验证结果显示,该文提出的作业远洋灯光渔船自动识别算法对实际作业灯光渔船的识别精度在92%以上,可以满足远洋灯光渔船日常监测的需求,可为进一步评估远洋光诱渔业捕捞努力量、推进远洋光诱渔业信息化管理以及打击非法、未申报和无管制的(illegal,unregulated,unreported,IUU)捕捞活动提供技术支持。  相似文献   

8.
Forest vertebrates are critical to the subsistence of many tropical forest dwellers enjoying little or no access to other sources of animal protein. Yet the ecological and socioeconomic value of forest wildlife is being undermined as many large vertebrate populations are driven to local extinction by unsustainable hunting practices. Although large mammals that are preferred by hunters are widely variable in their morphology and ecology, they share a set of life history traits, which make them particularly vulnerable to overhunting. In this paper we compile data on game harvest from 31 tribal and nontribal settlements in Neotropical forests to examine how mammal assemblages are affected by the history of hunting within settlement catchment areas. The structure of hunter-kill profiles is related to settlement age and size in an attempt to understand how changes in hunting pressure may affect prey selectivity and the structure of residual game assemblages. There was a predictable shift from a few large-bodied to several small-bodied species harvested by increasingly older villages. Settlement persistence thus explained a significant proportion of the variation in mean body mass and species richness of mammals harvested. We conclude that differences in prey species profiles obtained by subsistence hunters of different ethnic groups can be largely explained by the local depletion status of game stocks, particularly large mammals, rather than by cultural factors.  相似文献   

9.
The impact of hunting on wildlife is a complex phenomenon which varies in space and across time, and yet limited knowledge is available on it. This is especially the case of the indirect effects of hunting on the behaviour of target as well as non-target species. Here we analyze how hunting affected the spatial behaviour of 62 radiocollared roe deer (Capreolus capreolus) in a protected area adjacent to areas where hunting with hounds (target species: wild boar and hares) and stalking with rifles from high seats without dogs (target species: roe deer) were permitted during the hunting season. Our results showed that hunting caused a significant increase in the home range size of monitored deer, as well as a “reserve effect”, whereby roe deer used the protected area as a refuge from hunters. These behavioural responses were significant only at times when hunting with hounds was conducted, even though roe deer was not the target species of this technique. Reactions to the perceived risk of predation varied among age and sex classes, with yearling being more sensitive and using the protected area more than adults. As shown in our study, hunting harassment provoked by drives with hounds significantly affects the behaviour of non-target species. Therefore, the use of long-legged hounds represents a variable that should be carefully evaluated by wildlife managers in their management plans and conservation policies, especially when endangered or vulnerable species are present.  相似文献   

10.
为了合理优化舱室布局,提高渔船设计工作效率,该文针对船舶设计过程中存在舱室划分重复性工作多、涉及知识面广、设计人员容易忽略公约、法规中规定等问题,在分析舱室划分基本理论方法和设计特点的基础上,通过建立舱室划分专家系统知识库和推理机制平台,探索基于专家系统的舱室智能化设计方法在渔船舱室设计中的应用。该设计方法以Visual Basic为编程语言,以CATIA软件为平台进行二次开发,通过研发智能化程序模块,应用于某渔船设计过程,验证了程序的准确性和实用性。该程序的开发实现了输入较少数据推动快速建模能力,使舱室划分在满足渔船规则规范的同时,至少可以缩短整船设计周期5-10 d,为渔船智能化设计提供参考。  相似文献   

11.
Origin of agriculture and plant domestication in West Mesoamerica   总被引:1,自引:1,他引:0  
Recent paleoecological, archaeobotanical and genetic-molecular data are used to develop a hypothesis on the where, when, how and whom of plant domestication and the origin of agriculture in west Mesoamerica, and the formation of the maize-bean-squash multicrop milpa system and agro-food system which formed the base for development of ancient complex societies in this area. It is highly likely that about 10,000 before present (BP) human groups specializing in plant gathering and small game hunting in the dry tropical forest of the Balsas-Jalisco biotic morphotectonic province began the process of plant domestication and agriculture, using fire as a tool. Sympatric distribution of the putative wild ancestral populations of maize, beans and squash indicate the extreme northwest Balsas-Jalisco region as a possible locus of domestication. Diffusion of these domesticates to the rest of Mesoamerica would have occurred via existing biological-cultural corridors. The milpa agro-food system would have been established between 7,000 and 4,400 calendar years (cal) BP. The complex food technology developed in the northwest Balsas-Jalisco region between 4,500 and 3,500 BP, much more complex than in other areas at the time, also suggests this area as the origin of the milpa agro-food system. Further archaeobotanical research is needed to confirm this hypothesis. Exploratory, collection and conservation efforts are needed in these putative source populations, as well as studies on their adaptation to climatic, edaphic and biotic factors, before they are displaced by the African grasses and pesticides forming part of the region’s growing cattle industry.  相似文献   

12.
棉花根际促生细菌的研究进展   总被引:1,自引:0,他引:1  
综述了根际促生细菌(PGPR)的概念、研究手段、基因标记技术和荧光原位杂交技术在研究棉花根际促生细菌中的应用.植物根系可以分泌各种对微生物有益的物质,吸引微生物在根际的聚集.棉花凝集素对根际促生细菌菌株的胞外多糖具有凝集作用,在棉花根际促生细菌与棉花根部相互识别过程中具有重要作用,可以利用棉花凝集素作为筛选工具筛选对棉花具有促生作用的根际促生细菌菌株.基因标记技术证明棉花根际促生细菌能高密度地定殖在棉花根部,对棉花的生长起促进作用,并能抑制某些植物病原菌及根际有害微生物.分子生物学技术在微生物生态学领域的应用促进了棉花根际促生细菌的研究和应用,可以利用棉花根际促生细菌研发微生物肥料.  相似文献   

13.
We apply an age- and stage-structured model incorporating varying harem sizes, paternal care and infanticide to examine the effect of hunting on sustainability of populations. Compared to standard carnivore and herbivore models, these models produce different outcomes for sustainable offtake when either adults, or adult males are harvested. Larger harem size increases sustainable offtake whereas paternal care and infanticide lowers it. Where males are monogamous, populations are vulnerable to male offtake, regardless of paternal care. Surprisingly, an incidental take of 10% of other age-sex-classes has very little effect on these findings. Indiscriminate (subsistence) hunting of all age-sex classes has a dramatic effect on certain populations. Applying these behavior-sensitive models to tourist hunting in the Selous Game Reserve, Tanzania, we find that across the Reserve hunting quotas were generally set at sustainable rates except for leopard (Panthera pardus). In certain hunting blocks within the Reserve, however, quotas for eland (Taurotragus oryx), hartebeest (Alcelaphus buselaphus), lion (Panthera leo), reedbuck (Redunca arundinum), sable antelope (Hippotragus niger), warthog (Phacochoerus aethiopicus) and waterbuck (Kobus ellipsiprymnus) are set at unsustainably high rates. Moreover, particular blocks are consistently awarded high quotas. Behaviorally sensitive models refine predictions for population viability, specify data required to make predictions robust, and demonstrate the necessity of incorporating behavioral ecological knowledge in conservation and management.  相似文献   

14.
During a survey of otters in southern Italy signs were found at 16 (8·5%) of the 188 sites visited. The River Sele holds a potentially viable population of otters and there was a remnant population on the River Crati, but positive signs on five other rivers were restricted to single sites only. The overall position is bleak. Italian rivers were frequently found to be polluted, riparian vegetation is extensively managed or removed, and disturbance is high from the gravel extraction industry, fishing and hunting.  相似文献   

15.
Large ungulate populations are associated with the degradation of many forest plant communities, but it is unclear if these population sizes are strictly a contemporary phenomenon. Human exploitation models predict they are not, with ungulate numbers varying with long-term fluctuations in hunting pressure. Alternatively, human disturbance models predict that abiotic limitations normally restrict herbivores, with contemporary increases reflecting increased productivity associated with agriculture and forestry. Both can explain ungulate abundance, but may have different implications for plant conservation because they predict different levels of prior evolutionary exposure to herbivory. Here, I review historical records and stand structure studies from degraded oak savanna of western North America to examine whether current ungulate levels are strictly a contemporary phenomenon. Although it was impossible to quantify pre-European herd sizes, all evidence indicates a strong relationship between hunting pressure and ungulate abundance. Historical accounts repeatedly describe large herds of deer and elk at first European contact, followed by sharp declines immediately after colonization, and then rapid recovery beginning in the early 1900s as subsistence hunting waned. Stand structure data for oak woodland appear to support this model. Present-day oak woodlands mostly derive from mass recruitment from 1850 to 1910, coinciding with the near elimination of ungulates by hunting. Although these results suggest that large ungulate herds are not strictly a contemporary phenomenon, browsing intensity appears to be unprecedented given limited hunting, predator extirpation, and savanna fragmentation within productive pasture and early successional forest. Hunting pressure thus continues to be important, in that it is now largely absent.  相似文献   

16.
Hunting is one of the greatest conservation challenges facing tropical wildlife. Wildlife in Indian tropical forests are vulnerable to hunting, although data on hunting impacts from the region are limited. We use a meta-analysis of 143 hunting studies from India to identify the species and geographic regions most at risk, and to assess their legal protection. We found evidence of hunting in 114 mammal species, with larger-bodied mammals being particularly vulnerable. Although 75% of all studies focused on mammals, few actually quantified hunting impacts. Further, among studies of all terrestrial vertebrates where hunting was mentioned, only 6% focused exclusively on hunting. With further research, we expect that the suite of species known to be exploited by hunters will increase. We conclude that the Eastern Himalaya and Indo-Myanmar biodiversity-hotspot complex is particularly vulnerable to hunting. Quantitative studies of hunting impacts are urgently needed across India, especially in this biodiversity-hotspot complex.  相似文献   

17.
Recently, European wild rabbit (Oryctolagus cuniculus) populations have undergone a sharp decline that may be exacerbated by hunting. We investigate the effects of the timing of hunting on the conservation of wild rabbit using a model for rabbit population dynamics. Scenarios with different hunting rates and age strategies were simulated for different population qualities. We interviewed hunters to ascertain the degree to which they would accept a change in the timing of hunting. We also investigated the hunting pressure applied by hunters and its relationship with rabbit abundance. Modelling results indicate that the current hunting season has the greatest impact on rabbit abundance. Hunting in late spring optimises hunting extraction while conserving rabbit populations. When the rabbit population quality is low the effects of age strategies and the timing of hunting are less important than the effect of the hunting rate applied. Almost half the hunters would agree to policy changes. More than 75% of hunters implemented self-imposed hunting restrictions to improve rabbit populations, that were more frequently applied in high rabbit abundance areas. Therefore, changing the timing of hunting and increasing the participation of hunters in low abundance areas could optimise both the exploitation and the conservation of wild rabbit populations in southwestern Europe.  相似文献   

18.
This paper reviews the status, management and resources of National Parks in Spain. From 1954 to 1973 five new National Parks were created, in addition to those of Covadonga and Ordesa, covering 57,000 ha, although nearly all the land is now owned by the government. Resources provided for the maintenance of the Parks are inadequate and in 1974 amounted to only 12,200,000 pesetas (about £76,000 at 1974 exchange levels). In contrast much more money is provided for hunting and fishing reserves and more land is set aside for these purposes, although the benefits are enjoyed by a comparatively small number of people. Criticisms are made of the Institute for the Conservation of Nature (ICONA) for its short-sighted management policy and lost opportunities to improve the administration of the Parks.  相似文献   

19.
Most tropical forest landscapes are modified by humans, but the effects of these changes on rural hunting patterns and hunted vertebrate populations remain poorly understood. We investigated subsistence hunting patterns across a highly heterogeneous landscape mosaic in the Brazilian Amazon, where hunters from three villages had access to primary forest, active and fallow agricultural fields, and active and fallow Eucalyptus plantations. Landscape composition and the areas used by hunters were defined using a remote-sensing approach combined with mapping. We quantified hunting effort accounting for the availability and spatial distribution of each habitat. Overall, 71% of the kills were sourced in primary forest, but hunting in primary forest, which was often combined with other extractive activities (such as Brazil nut harvesting), yielded the lowest catch-per-unit-effort of all habitats. Hunting effort per unit area was highest in fallow fields, followed by primary forest, and both of these habitats were over-represented within village hunting catchments when compared to the composition of the available landscape. Active and fallow fields sourced a limited number of species known to be resilient to hunting, but hunting had additional benefits through crop-raider control. In contrast, hunting pressure in active and fallow plantations was low, despite a high catch-per-unit-effort, presumably because there were limited additional benefits from visiting these habitats. These results indicate that large-scale tree plantation and forest regeneration schemes have limited conservation potential for large vertebrates, as they support few forest specialists and fail to attract hunters away from primary forest.  相似文献   

20.
Farmers normally practice conventional tillage ((CT), disk plowing, cultivator, rotavator, and leveling) in cotton (Gossypium hirsutum L.) with 15 cm intra-row spacing to avoid risks of poor plant stand and obtain higher yield. However, CT is costly besides it has adverse effects on soil and crop when sown after wheat. Conservation tillage [zero tillage (ZT) or reduced tillage (RT)] with suitable spacing can reduce production cost, increase cotton yield and quality, and it has favorable effects on soil properties. Field experiments were conducted to evaluate cotton response to tillage (ZT, RT, and CT) and intra-row spacing (15.0, 22.5, 30.0, 37.5 cm). Results revealed that RT produced higher bolls plant?1, boll weight, seed cotton yield, ginning out turn, fiber length and strength than ZT and CT. Mean boll weight, seed cotton yield, earliness, and fiber qualities were optimum at 22.5 cm spacing. Tillage × spacing interaction showed optimum boll weight, earliness, and fiber strength with 15.0–22.5 cm spacing under RT. CT with 22.5 cm spacing also performed better in terms of boll weight and fiber strength; however, 15.0 cm spacing resulted in earlier maturity. RT with 22.5 cm spacing is an alternative to CT for higher yield, earliness, and quality of cotton besides environmental safety.  相似文献   

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