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1.
Himalayan medicinal plants are threatened by large scale exploitation for trade. Research applicable to their sustainable use is largely lacking. We analyze the effects of different harvesting patterns on the population ecology of two highly threatened Himalayan medicinal plants, Nardostachys grandiflora (Valerianaceae) and Neopicrorhiza scrophulariiflora (Scrophulariaceae), in Shey-Phoksundo National Park and in its buffer zone in northwestern Nepal. We first documented local harvesting approaches of two major user groups, amchi (traditional doctors trained in Tibetan medicine), who harvest plants in a selective manner for local health care purposes, and commercial collectors, who harvest unselectively and at much higher intensity for trade. We then applied the selective harvesting approach of amchi in an experiment to test the effects of different harvesting levels on the population ecology of these two species. These experiments revealed a positive effect of low harvesting levels on plant density, but recruitment and survival rates decreased with increasing harvesting levels. We also analyzed the effect of high harvesting pressure for trade on the population ecology of N. grandiflora. Recruitment and survival rates were higher in N. scrophulariiflora than in N. grandiflora; the latter species is more vulnerable to harvesting than the former. The difference between them in sustainability of harvest is related to differences in their strategies of vegetative reproduction and in harvesting practices associated with these strategies. Management of Himalayan medicinal plants can be improved by taking harvesting patterns, plant life forms and growth patterns into consideration.  相似文献   

2.
[目的] 分析阿拉善高原荒漠区植物的科属组成、生活型和水分生态型、保护植物和资源植物,为高原荒漠植物资源合理开发利用、生物多样保护和生态环境修复等提供依据。[方法] 通过植被调查和查阅相关资料分析了阿拉善高原荒漠植物资源的科属组成、生活型、水分生态型和特殊物种。[结果] 阿拉善高原荒漠植物共有70科284属727种。从植物生活型来看,以多年生草本最多,其次是一、二年生草本和灌木;从水分生态型来看,中生植物最多,其次是旱生植物和旱中生植物。国家级及自治区级保护植物共有24种,世界自然保护联盟(IUCN)红色名录植物有26种,药用植物210种,饲用植物186种。[结论] 在阿拉善高原荒漠区,菊科、藜科、豆科和禾本科植物等为优势科,黄芪属、风毛菊属和蒿属等为优势属;以多年生草本为主,植物旱生化明显,珍稀濒危植物种类较多,资源植物十分丰富。在合理利用植物资源时,需要根据植物资源现存状态及其价值类型等进行管理和保护。  相似文献   

3.
The need for a global priority list for threatened plants has been widely recognized by the conservation community, yet the threatened status of the majority of the world’s plants species remains poorly known. This is especially true in the tropics and the oceanic islands of the Pacific, where progress towards the targets of the Global Strategy for Plant Conservation (GSPC) 2011–2020 is hindered by the paucity of complete species distribution data. Here we outline a new methodology to undertake threatened species assessments where detailed contemporary population data is lacking. This new interdisciplinary methodology draws upon the synthesis of archaeological and botanical data to calculate a percentage of long-term decline in habitat quality. We use this method to assess the threatened status of the endemic flora of Palau, Micronesia, a Pacific island nation known for its high levels of plant diversity and endemism, by utilizing data extending back to human colonization of the archipelago. For Palau, we calculate the percentage of a long-term decline in habitat quality to be 31–39% of the total available range of 55% of the endemic plant species. These data are also used to address a long debated question in the western Pacific: Are the origins of the savanna vegetation anthropogenic? Strong evidence for anthropogenic savannas in Micronesia support the estimated extent of historic deforestation in Palau. This new method worked well in our case study, and can be used in other locations with incomplete species distribution data to establish a first basis for conservation prioritization.  相似文献   

4.
Abstract

In Iran, the recent spike in herbal medicines has led to a corresponding price increase. Therefore, these montane species are now widely field cultivated. Medicinal plant consumers strongly prefer organically grown plants, and farmers are responding to this market. However, the effects of organic amendments on medicinal plant nutrient content and yield have been poorly studied. Therefore, this study measured the effects of different organic treatments on the growth of fenugreek and goat pea. Plants were grown to compare the effects of composted municipal waste (CMW), vermicompost (VC), and urea nitrogen (N) to untreated field soil (C0). Germination percentage was significantly higher in urea N (76.5%), CMW (75.5%), and VC (51.6%) compared to C0 (36.3%). Fenugreek performed better in organic amendment treatments than goat pea. Urea N also increased fenugreek plant dry matter significantly compared to C0, but this increment was not as high as CMW or VC. Plants grown in VC had higher whole plant N content (3.2%) than those grown in CMW (2.8%) and plants grown in urea N (2.6%). Plants treated with CMW (8613?mg kg?1) and VC (8503?mg kg?1) had a significantly higher P content than those treated with N (7430?mg kg?1) or C0 control grown (7236?mg kg?1). Application of VC significantly increased plant K content (2483?mg kg?1) compared to CMW (1850?mg kg?1), N (1750?mg kg?1), and C0 control (1716?mg kg?1). Even without fertilization, both plant species contained a considerable amount of micronutrient elements.  相似文献   

5.
为探明药用植物根围AM真菌遗传多样性,于2010年8月在河北省安国市3个样地(中药材种植基地、霍庄、大户村)用随机抽样法采集7种中药材根围土壤样品,分离筛选双网无梗囊霉(Acaulospora bi-reticulata)为试验菌种,进行孢子DNA提取、PCR扩增、序列测定及聚类分析,研究了双网无梗囊霉遗传多样性与土壤因子的关系,并选取两条代表菌株所测序列,连同从NCBI数据库中下载的4属28种AM真菌相应序列构建系统发育树。结果表明,双网无梗囊霉可侵染不同样地不同宿主植物,3个样地7种中药材双网无梗囊霉DNA相似性达99.2%以上,其遗传特征保持了高度稳定性,双网无梗囊霉在样地和植物间具有广谱性。同一样地不同中药材根围土壤因子相似性很高,AM真菌DNA碱基序列相似系数也很高,而不同样地同一中药材根围AM真菌DNA碱基序列相似系数低于前者,可见遗传多样性与土壤因子密切相关。土壤因子对双网无梗囊霉基因序列的影响大于宿主植物的影响。  相似文献   

6.
A priority list of 323 plant species was created through a consultative process for ex situ conservation in the recently inaugurated Israel Plant Gene Bank (IGB). The IGB is set up to preserve plant genetic resources and the endangered genetic variability of the Israeli flora. Upon its inauguration, we consulted with the country’s leading plant breeders and botanists in an attempt to create a list of the most important plant species to be included in the initial collections. The list includes crop wild relatives (CWRs), selected according to their contribution to humans: edible plants (grains, vegetables, oil); forage plants; species with potential industrial and biotechnological applications (e.g. spices, medicinal plants, aromatic plants, fibers, dyes), and species with horticultural and forestry potential. We further ranked the species on the basis of assessed values for each of seven characteristics: distribution range in the country; abundance; rarity of the growing habitats; endemism; red number index—representing imminent threat of extinction; availability of samples in Israeli collections, and genetic relationship to cultivated crops. The sum of the assessed values for these seven characteristics was used to group the species on the list into four main prioritized-collection schemes. Statistical analysis indicated that all attributes had similar influence on the collecting prioritization scheme. In general, rare species with low abundance in their growing habitats were ranked in the highest priority group, while highly distributed species were sorted together into a lower priority group. The prioritization scheme will be used to optimize the collection in the IGB with the aim of establishing its collecting activities.  相似文献   

7.
Bush encroachment is a serious environmental and economic problem in Namibia, but little is known about impacts on native reptile diversity. Area-confined visual surveys were used to examine a diurnal lizard assemblage in central Namibian commercial ranchlands. Surveys were conducted in plots of open savanna habitat and proximal bush-encroached habitat. The following four species comprised 97.5% of all lizard observations: Pedioplanis undata, Mabuya varia, M. striata, and Lygodactylus bradfieldi. Pedioplanis undata was terrestrial, and the remaining three species were largely arboreal in our study plots. Mabuya varia was found in all savanna plots but was absent from all bush-encroached plots. Two species (P. undata and L. bradfieldi) were less abundant in bush-encroached plots. One species (M. striata) was more abundant in bush-encroached plots than in open savanna plots. Arboreal lizards demonstrated an avoidance to invasive woody plant species. Decreased diversity of habitat structure in bush-encroached habitats appears to influence native savanna lizard assemblages. Our results are consistent with accumulating evidence suggesting that bush encroachment and its associated ecological impacts are reorganizing savanna ecosystems throughout southern Africa.  相似文献   

8.
Aboriginal people in remote Australian communities have limited opportunity to participate in the market economy. The Aboriginal arts and craft industry offers an important option to generate cash income and the sustained supply of native plants used in production is vital. We assessed the current harvest of a rainforest tree species commonly used for sculpture, Bombax ceiba. Information from field surveys, a regional rainforest inventory and sales figures from the Maningrida region were used to estimate the population size and structure of B. ceiba, the harvest intensity of patches and the economic value of the harvest. We estimate the density of B. ceiba to be 105.10±12.32 stems ha−1 and a regional population of 76615±14063 stems. A cumulative harvest over 20 years of 6% suggests approximately 4596 stems harvested, and the harvest was worth about $200,000 over the last three years. The majority (80%) of harvested stems coppiced and were suitable for harvesting. Logistic regression suggests both distance to outstation and township influence harvesting intensity, with some localised over-harvest. Rainforests provide a valuable resource to Aboriginal artists in Maningrida and their maintenance provides important conservation benefits to the Australian community.  相似文献   

9.
10.
Trace elemental concentrations (Fe, Ni, Mn, Cr, Co, Cu, Zn, Pb, Cd, and As) in aerial biomass (stems, leaves, and flowers) of the medicinal plants Teucrium chamaedrys, T. montanum, and T. polium growing on serpentine soils in Bulgaria were examined in relation to the total element contents in their respective rhizospheric soils. The objectives of the study were to evaluate: (1) elemental concentrations in plant tissues and associated soil samples together with the plants ability to tolerate/accumulate metal concentrations; (2) correlations between total metal concentrations in plants and their rhizospheric soils. Metal concentrations varied across species and sites. Their levels in plant tissues from nonserpentine sites were always lower compared to those from serpentine ones. The highest concentrations for Fe, Ni, Mn, Cr, As, Cu, and Pb were found in T. polium. Positive correlation coefficients were established between Ni, Cr, Fe, Co, and Cu in plants and Ca in the soil. None of the species tested hyperaccumulated metals although the metal concentration in some of them exceeded the range naturally found in plants. The Teucrium species can be considered as “excluders”, containing relatively low metal concentrations in their aerial parts (stems, leaves, and flowers) even in cases of high elemental concentrations in the rhizospheric soil. In all three medicinal plants, metal concentrations for toxic elements were above the permissible limits for pharmaceutical purposes. Therefore, plants found on serpentine bedrock are not recommended to be collected for pharmaceutical purposes.  相似文献   

11.
The field experiment was conducted to study the effect of conventional chemical fertilizer (urea),conventional biofertilizers (charcoal based) and organic matrix entrapped biofertilizer; (OMEB: a consortium of Azotobacter chroococcum, Azospirillum brasilense and Pseudomnas putida entrapped with clay soil, neem leaves, and cow dung in ratio of 1:1:1 and 15% saresh (plant gum of Acacia sp.) in various doses on growth parameters of Rauwolfia serpentina in terms of root length, shoot length, number of leaves, number of roots and fresh and dry weight of roots and shoots. Replacement of conventional chemical fertilizer by the consortium of biofertilizers (un-entrapped) increased plant growth in a dose dependent manner up to triple dose of the recommended dose (RD) of biofertilizers (1.80 kg ha-1). This increase in plant growth was not up to the level which appeared in the application of RD of urea. Entrapment of the same biofertilizers in an organic matrix mentioned above enhanced the plant growth similar to that observed for urea. The percentage increase of 9.57 and 7.54 in fresh weight (FW) and 11.93 and 11.12% in dry weight (DW) of shoot and 17.94 and 37.87% in FW of roots and 31.90 and 50.08% in DW of roots were recorded in 75 days old plant by the application of OMEB- triple dose over the conventional biofertilizers triple dose and recommended dose of urea. Conventional biofertilizers enhanced the availability of nitrate, nitrite and phosphate in the roots and leaves of the plant over application of urea as well as conventional biofertilizers. This formulation also increased alkaloid contents of in the roots of this plant. Microbial population of soil was also improved indicating enhanced soil fertility with application of OMEB. The results indicate that replacement of chemical fertilizers with microbial biofertilizers is possible with application of higher dose of biofertilizers entrapped into the organic matrix for the cultivation of medicinal plants like R. serpentina.  相似文献   

12.
African medicinal plant species are increasingly threatened by overexploitation and habitat loss, but little is known about the conservation status and ecology of many medicinal species. Mondia whitei (Apocynaceae, formerly Asclepiadaceae), a medicinal liana found in Sub-Saharan Africa, has been subject to intensive harvesting and habitat loss. We surveyed M. whitei in Kakamega Forest, the largest of three remnant Kenyan forests known to contain the species. In 174 100 m2 plots, we quantified the status of M. whitei and investigated its relationships with land use, disturbance and harvesting. With average adult densities of 101 plants/ha, M. whitei is not locally rare in Kakamega. However, the absence of flowers and fruits, together with a spatial disconnect between adults and juveniles, suggests that sexual regeneration is patchy or infrequent. Comparing among habitat types, we found that plants were most abundant in regenerating indigenous forest managed by the Forest Department, which permits some extractive uses. Conversely, plants were largest in indigenous forest managed by the Kenya Wildlife Service, which prohibits extractive uses. Most anthropogenic disturbances were not associated with M. whitei, but plant occurrence and density were higher along paths used by livestock than along other types of paths. Larger individuals appeared to be preferentially harvested, but adult plants were more likely to occur in harvested plots than un-harvested plots. This work emphasizes that restrictions on disturbance and extractive use do not automatically promote medicinal plant conservation. Moreover, harvesting may have important genetic and demographic consequences that are overlooked by studies focused on numerical losses.  相似文献   

13.
The objective of grassland management is to maintain keystone species, as well as species diversity, to promote a particular community structure, or to preserve specific ecosystem processes. Studies of grassland management rarely ascertain the effects on rare plant species, although conservation plans for rare herbaceous plants often recommend habitat management as well as restoration activities. Indeed, conservation biology has evolved from a relatively species-specific discipline into one more focused on larger scale issues such as ecosystem function, community composition and habitat restoration. Few studies have tested whether species of concern are adequately managed with a community or ecosystem-level approach. In this study, we evaluate whether community-level management of white-tailed deer and woody brush improves the viability of the rare annual plant species, Agalinis auriculata (Earleaf false foxglove; Orobanchaceae). Reducing deer browse and removing brush each positively affect plant vital rates. Brush removal increases the proportion of plants that reach the largest size class. Reducing deer browse increases the fertility of plants, particularly those in the largest size class. We report on demographic matrix models created with data from five populations of A. auriculata studied across 4 years. We find that both management activities positively affect the non-target plant species and are, in fact, necessary for A. auriculata to persist. Conservation of A. auriculata at our study sites requires both reducing the density of white-tailed deer and brush removal. Our study demonstrates that management at the community and ecosystem levels can be compatible with conservation goals at the species and population levels.  相似文献   

14.
We propose a method to establish regional-level priorities for plant species that is based on three criteria. These involve two main criteria associated with species rarity, (a) small range size and thus regional responsibility and (b) low population numbers and thus local rarity, and a third criteria associated with habitat vulnerability to distinguish species currently threatened by human activities. Application of the method shows how the three criteria can be objectively and readily quantified (using a system of equal numbers of ranks) and combined into a hierarchy of priorities. We show how this can be done by using regional responsibility as a first order priority followed successively by local rarity and habitat vulnerability. Since the criteria are closely associated with rarity, this method is easily understandable for decision makers. We illustrate the application of the method to plants (a species rich group) at two regional scales where the objectives are different. If adapted to the availability of different types of data, the three criteria could be used to produce comparable lists in different countries and regions.  相似文献   

15.
In the Lower Mekong Basin, paddy fields often appear as mosaics, with soil mounds covered by trees or other plants in a spotty distribution. These soil mounds are commonly named termite ‘lenticular mounds’ because termite bioturbation is considered to be at their origin. Termite mounds host a large diversity of animals and plants, increasing landscape patchiness. Because the preservation of these islands of biodiversity is threatened by modern agricultural practices, the aim of this study was to quantify their abundance and the services they provide to the local population. The abundance of mounds and their use by the population were quantified in a catchment in Cambodia. We found that mounds density reached ~2 mounds ha−1. Interviews carried out within the catchment showed that most of the interviewees used mounds for increasing the fertility of their field and for the cultivation of rice and other plants (e.g. sponge gourd and pumpkin). In addition to their potential to increase plant productivity, the survey revealed that animals (rats and snakes), mushrooms and 13 plant species found on or in mounds were consumed by the population. In addition to potentially contributing to an increase in food diversity, mounds also impacted farmers' health by allowing access to 20 medicinal plant species and indirectly via a reduction in pesticide use. In conclusion, this study is the first attempt to quantify the large number of services provided by termite mounds in Cambodia. This increase in the knowledge of the diversity of environmental and socioeconomic services provided by termite mounds is likely to contribute to their preservation and provide a basis for the sustainable management of biodiversity in paddy fields in the Lower Mekong Basin region.  相似文献   

16.
The Pacific Northwest is the main source of commercially harvested forest moss in North America, but management guidelines have only included this nontimber forest product for ca. 15 years and research on sustainable harvest practices is barely a decade old. This review summarizes the results of recent research, identifies future research needs, and proposes guidelines for the sustainable management of tree moss (a mixture of mosses and liverworts). The epiphytic species most affected by harvest are Isothecium myosuroides, Neckera douglasii, and Porella navicularis, but dozens of taxa are thought to be impacted. Harvest impacts include reductions in biomass and cover and changes in relative species composition, but it is too early to tell if the species composition will return to pre-harvest conditions. Biomass recovery is slow and estimated rotation periods are 15-25 years. Inventory estimates are still lacking, but harvestable quantities of epiphytic moss are most abundant in low elevation and riparian areas and absent in stands that are very dark and/or lack hardwood tree and shrub species (e.g., <70-year-old Douglas-fir (Pseudotsuga menziesii) plantations). Future research should focus on locating unimpacted reference sites and evaluating the ecosystem functions provided by harvestable moss mats, including the provision of habitat and nutrient and water cycling. Management recommendations include prohibiting commercial moss harvest in forests managed toward old-growth condition, obtaining region-specific estimates of resource inventory and recovery rates, and rotating areas open for moss harvest to allow sufficient recovery between harvest entries.  相似文献   

17.
18.
白头叶猴采食植物的再研究   总被引:1,自引:1,他引:0  
2006年使用了较先进的录像设备,结合单筒望远镜对白头叶猴进行了全天候的跟踪观察和录像,使我们有可能更准确地仔细鉴定白头叶猴采食的植物及采食部位,也为动物生态的研究提供一个可重复验证的方法。经统计分析发现:白头叶猴属热带分布的灵长类动物,全以植物的各部分器官为食;被采食的植物大多数为热带分布的物种,是当地植被重要的建群种或优势种;在白头叶猴采食的物种中,有一部分是人类使用的药用植物;其中落叶成分和喜钙植物都较多;初步认为白头叶猴对不同的植物其喜食程度有明显不同。  相似文献   

19.
The common hamster (Cricetus cricetus) has suffered a dramatic decline in Western Europe though the species is characterized by an extremely high reproductive potential. An individual-based model was developed to determine the risk factors which lead to population decline and to investigate management actions for viable populations. Demographic stochasticity was considered by (a) describing reproduction on an individual basis and (b) distinguishing behavioural patterns according to age and sex. Unknown model parameters were determined by comparing field data and simulated patterns in a specific multi-criteria fashion. We conclude that disturbances such as agricultural management and highway construction are most dangerous to the common hamster in autumn. Complex land management is required which should aim at reducing habitat-specific mortality and favouring the safeguarding of adult and subadult females to protect the most sensitive component of the population. According to the model results, large habitat size is not sufficient for survival, and habitat connectivity may be even more important. Late timing of the harvest and following cultivations was most favourable for population survival.  相似文献   

20.
辽宁西北部主要绿化树种对空气颗粒物滞留能力研究   总被引:1,自引:0,他引:1  
采用洗脱法测定了辽西北地区阜新市15种常见绿化树种单位叶面积滞留粗颗粒物(TSP)及细颗粒物(PM_(2.5))的质量,分析比较了15种树种叶片去除TSP和PM_(2.5)能力以及随着空间变化的规律。结果表明:(1)不同树种单位叶面积TSP和PM_(2.5)滞留量均存在显著差异,变化范围分别为3.68~5.94g/m~2和0.47~0.92g/m~2,树种间滞留能力的差值可达2倍左右。(2)在同一个功能区不同树种滞留TSP和PM_(2.5)的差异由树冠高度(绿篱灌木乔木)和叶表面粗糙度(叶表面沟槽宽度的不同可能是沟槽宽度过宽和过窄均不利于叶片捕集颗粒物,且颗粒物滞留量随沟槽深度增加而增大)以及叶片比叶重(比叶重大的滞尘量大)等所引起。(3)在不同功能区同一树种单位叶面积滞留TSP量的排序为工业区商业交通区露天矿区清洁区,而PM_(2.5)滞留量则无明显差异。乔木中新疆杨、灌木中紫丁香的单位叶面积滞留量与单株滞留量都较高,起到明显的降尘作用,是沙尘频发的辽西北地区城市绿化树种的优先之选。  相似文献   

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