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1.
森林遗传资源保护研究进展   总被引:1,自引:0,他引:1  
森林遗传资源的保护事关现代及后代的利益,已引起全球的极大关注,自70年代以来,就地保护与迁地保护作为主要的战略在森林遗传资源保护实践中使用。一般来说森林遗传资源的就地保护可以通过建立自然保护区来实现。迁地保护主要包括种子库、田间基因库、种子园及细胞或组织培养等技术。就地保护和迁地保护应当相互补充,两者结合使用是保存森林遗传多样性的有效方法。对森林遗传资源保护战略的选择以及因贸易而濒危的热带材用树及其保护问题也作了简要评述。  相似文献   

2.
The approaches to enlarge the protected areas are deeply embedded in the conservation planning.In practice,however,even in some sites of top conservation priority,there exist problems of inefficient conservation for lack of funding,to say nothing of assisting all species under threat from the viewpoint of conservationists.Identifying priority sites for conservation and establishing networks of minimum priority sites (NOMPS) are helpful for promoting the transition from number and size oriented,to quality and effectiveness oriented practices of biological conservation,and for realizing the target of biodiversity conservation with the most benefits for the least costs.Based on heuristic algorithm and integer linear programming (ILP),we propose a refined method of heuristic integer linear programming (HILP) for quantitative identification of the NOMPS to protect rare and endangered plant species (REPS) in Guangdong Province,China.The results indicate that there are 19 priority sites which are essential for protecting all of the 107 REPS distributed in 83 sites in Guangdong.These should be the paramount targets of financing and management.Compared with the ILP,which uses minimum number of sites as the only constraint,HILP takes into consideration of the effect of species richness,and is thus more suitable for conservation practices though with a little more number of priority sites selected.It is suggested that ILP and HILP are both effective quantitative methods for identifying NOMPS and can yield important information for decision making,especially when economic factors are constraints for biological conservation.  相似文献   

3.
The approaches to enlarge the protected areas are deeply embedded in the conservation planning. In practice, however, even in some sites of top conservation priority, there exist problems of inefficient conservation for lack of funding, to say nothing of assisting all species under threat from the viewpoint of conservationists. Identifying priority sites for conservation and establishing networks of minimum priority sites (NOMPS) are helpful for promoting the transition from number and size oriented, to quality and effectiveness oriented practices of biological conservation, and for realizing the target of biodiversity conservation with the most benefits for the least costs. Based on heuristic algorithm and integer linear programming (ILP), we propose a refined method of heuristic integer linear programming (HILP) for quantitative identification of the NOMPS to protect rare and endangered plant species (REPS) in Guangdong Province, China. The results indicate that there are 19 priority sites which are essential for protecting all of the 107 REPS distributed in 83 sites in Guangdong. These should be the paramount targets of financing and management. Compared with the ILP, which uses minimum number of sites as the only constraint, HILP takes into consideration of the effect of species richness, and is thus more suitable for conservation practices though with a little more number of priority sites selected. It is suggested that ILP and HILP are both effective quantitative methods for identifying NOMPS and can yield important information for decision making, especially when economic factors are constraints for biological conservation.  相似文献   

4.
5.
The growing development of biological products highlights the social and environmental responsibility that several industrial companies are facing in recent years. In this context, the advancement of bioprocessing as an alternative for exploring the potential of ecologically based products, especially in biofuels, food, and agro-industrial business, exposes the rational efficiency of the application of renewable sources in different industrial segments. Industries strongly associated with food production concentrate large amounts of wastes rich in bioactive compounds. A range of highly effective technologies has been highly explored to recover large concentrations of prominent compounds present in these materials. The advances in this scenario assurance value addition to these by-products, in addition to highlighting their various technological applications, considering the biorefinery and ecologically based production concepts. Accordingly, this review article described a detailed and systematic approach to the importance of using bioactive compounds and exploring the main sources of these elements. Also, some recent and innovative research that has achieved encouraging results was highlighted. Furthermore, the study included the main extraction technologies that have been investigated as a strategy of prospecting the application of bioactive compounds and optimizing the processes for obtaining natural compounds from plant sources. Finally, future outlooks were presented to contribute to the innovative opportunities and applicability of highly promising technologies and manipulations of bioactive compounds from a range of perspectives.  相似文献   

6.
福建永安植物资源特点、现状及保护利用   总被引:3,自引:1,他引:2  
永安市位于福建省中部,自然条件优越,植物资源丰富。本文阐述该区植物资源特点、现状,并提出保护利用对策。  相似文献   

7.
Domestic livestock in Nepal belong to 17 species, including five Bovidae (and interspecific hybrids of two of them), seven Aves, two Equidae (not including mules), pig (Sus scrofa), rabbit (Oryctolagus cuniculus) and elephant (Loxodonta africana). Cattle (Bos taurus and Bos indicus) are the most numerous quadruped, followed by goats (Capra hircus), buffalo (Bubalus bubalis) and sheep (Ovis aries). Domestic fowl (Gallus domesticus) are the most common poultry, followed by pigeons (Columba livia) and ducks (Anas platyrhyncos). Government policy is to upgrade and replace local types with improved stock. This policy has had limited success through lack of funding, inconsistent long-term objectives and an inability to pursue programmes in traditional farming systems. The purity of native types is being lost in some areas due to informal programmes by farmers themselves. Except for one type of goat there are no conservation programmes for native breeds. Wild relatives of livestock, including arnee (Bubalus arnee), gaur (Bibos gaurus), wild boar (Sus scrofa), jungle fowl (Gallus gallus) and rock dove (Columba livia), are being infiltrated by genes of domestic animals. Little has been done to characterize Nepal's livestock resources yet continuous attempts have been made to replace them. Conservation needs are to: (i) identify all genetic resources comprising the gene pool of species used as domestic livestock; (ii) develop and use the associated diversity to increase production, achieve sustainable systems and meet demands for particular products; (iii) monitor resources represented by small numbers or that are being displaced; and (iv) preserve resources not in current demand. A start has been made on this by Nepal's membership of a regional network.  相似文献   

8.
Philip Nyeko 《Biotropica》2009,41(4):476-484
Very little is known about the diversity of arthropods in the fast-disappearing fragments of natural forests in sub-Saharan Africa. This study investigated: (1) the influence of forest fragment characteristics on dung beetle species richness, composition, abundance, and diversity; and (2) the relationship between dung beetle assemblages and rainfall pattern. Beetles were sampled through 12 mo using dung baited pitfall traps. A total of 18,073 dung beetles belonging to three subfamilies and 45 species were captured. The subfamily Scarabaeinae was the most abundant (99%) and species rich (89%). Fast-burying tunnellers (paracoprids) were the most dominant functional group. Catharsius sesostris, Copris nepos , and Heliocopris punctiventris were the three most abundant species, and had the highest contributions to dissimilarities between forests. With few exceptions, dung beetle abundance, species richness, and diversity were generally higher in larger forest fragments (100–150 ha) than in smaller ones (10–50 ha) and the nature reserve (1042 ha). Forest fragment size had a highly significant positive relationship with beetle abundance, but only when the nature reserve is excluded in the analysis. Dung beetle abundance and species richness showed direct weak relationships with litter depth (positive) and groundcover (negative) but not tree density, tree species richness, and fragment isolation distance. Dung beetle abundance and species richness were strongly correlated with monthly changes in rainfall. Results of this study indicate that forest fragments on agricultural lands in the Budongo landscape, especially medium-sized (100–150 ha) ones, represent important conservation areas for dung beetles.  相似文献   

9.
中国野生稻遗传资源的保护及其在育种中的利用   总被引:15,自引:0,他引:15  
我国有三种野生稻,即普通野生稻(Oryza rufipogon)、药用野生稻(O.officinalis)和瘤粒野生稻(O.meyeriana)。这三种野生稻均被列为国家二级保护植物(渐危种)。调查结果表明,野生稻由于其自然群落大量丧失而濒危,濒危程度为普通野生稻>药用野生稻>瘤粒野生稻。造成濒危的主要原因是人为的破坏活动。人类的经济活动导致了野生稻生境丧失、生境质量不断恶化、栖息地越来越少;人类的活动也导致了外来种的入侵。目前,对野生稻的保护措施主要有就地保护(原地保护或原位保护)和迁地保护(易地保护或异位保护)。易地保护包括以种子保存的种质厍、以种茎保存的种质圃和以器官培养物作为材料的超低温保存。野生稻具有许多优良特性,如特强的耐寒性、高的抗病虫性、优质蛋白质含量高、功能叶片耐衰老的特异性、特强的再生性、良好的繁茂性及生长优势等等,这些优良特性已被广泛用于水稻常规育种和杂交育种中,并取得了巨大的社会效益和经济效益。有关野生稻生物技术方面的研究,如花药培养、原生质培养、体细胞杂交和基因工程等方面已取得了较大的进展。野生稻将在水稻育种中发挥越来越重要的作用。  相似文献   

10.
本文讨论环境污染对植物伤害的症状、植物抗污性标准、环境监测植物的优点和选择指标。在此基础上,筛选出福建三明地区环保植物资源的种类,并推荐适用于当地不同环境特点和功能的环保植物。  相似文献   

11.
云南省红豆杉资源的分布,利用现状与保护和可持续利用   总被引:6,自引:0,他引:6  
红豆杉属(TaxusL.)植物是提取抗癌新药紫杉醇(taxol)的原料,在云南省有2种1变种,分布范围较广,但多散生,野生数量计有3540920株。近年来,红豆杉资源的开发利用研究进展较快,但资源的破坏和浪费严重,加之该植物生长缓慢,对生境的要求高,营造原料林困难,供求矛盾十分突出,为此提出了红豆杉资源的保护和可持续利用对策。  相似文献   

12.
河西走廊的麻黄资源及其保护   总被引:9,自引:0,他引:9  
河西走廊的麻黄资源及其保护满多清,杨自辉(甘肃省治沙研究所,武威733000)关键词麻黄;植物资源;保护TheresourcesofEphedraTourn.exL.andtheirconservationinHexicorridor¥ManDuo-...  相似文献   

13.
《Plant Ecology & Diversity》2013,6(2-3):197-215
Background: Temporary ponds, an abundant habitat in the Maghreb region and notably in Morocco, have a high conservation value. However, they are mainly known from the north of the country.

Aims: The aim of this work was to characterise the vegetation of Moroccan temporary ponds along a combined gradient of latitude and anthropogenic pressure.

Methods: Eighty-five ponds distributed along a north–south gradient of 750 km were sampled. For each pond, all vegetation was surveyed (flooded and dry parts) and the local abiotic characteristics were measured during two successive hydrological cycles. The prevailing anthropogenic pressures were also identified and were attributed an impact score.

Results: Eighty-one characteristic pond species (including 17 rare species) were recorded, with several new distribution data in the southern part of the latitudinal gradient. Plant communities were related to climatic and anthropogenic factors, but mostly to local factors, such as maximum water depth and soil pH. The northern ponds (wettest macroclimate) were rich in characteristic species and rare species, while the southern (driest macroclimate) ponds were more species poor.

Conclusions: In addition to the direct impact of increasing human activity, a further reduction of the floristic richness of temporary ponds is expected due to climatic changes. This is particularly the case for characteristic species which have a high conservation value.  相似文献   

14.
Knowledge of spatial patterns of biological diversity is fundamental for ecological and biogeographical analyses and for priority setting in nature conservation, particularly in West Africa where the existing high biodiversity is increasingly threatened by human activities. The maximum entropy approach was used to model the geographic distribution of 3,393 vascular plant species at a spatial resolution of 0.0833°. Species richness decreases along temperature and precipitation gradients with high species numbers in the south and lower numbers towards the north of the transect. All centres of plant species diversity are confined to humid areas in concordance with the high positive correlation between species richness and rainfall which appears to be the most important delimiter for the distribution ranges of many species in the area. The effectiveness of the existing protected areas at regional and national levels is investigated based on the proportion of species covered. Considering the whole study area, 95% of all species are covered by protected areas according to their distribution ranges. However, the proportion of species covered is considerably lower for some countries such as Benin and Togo. Our results could provide guidance for essential land use management interventions to decision‐makers and conservationists in the region.  相似文献   

15.
本文从青藏高原药用植物资源的分布情况,资源特点以及相应的保护利用等方面简要的概括了近来的研究新进展,旨在理清相关研究情况,为相应的研究工作提供参考。  相似文献   

16.

Background

Humans threat the populations of tree species by overexploitation, deforestation, land use change, and climate change. We present a novel threat assessment at intraspecific level to support the conservation of genetic resources of 80 socioeconomically viable tree species in South America. In this assessment, we evaluate the threat status of Ecogeographic Range Segments (ERSs). ERSs are groups of populations of a specific species in a certain ecological zone of a particular grid cell of a species’ geographic occupancy.

Methods

We used species location records to determine the species distributions and species‐specific ERSs. We distinguished eight threat situations to assess the risk of extirpation of the ERSs of all 80 species. These threat situations were determined by large or little tree cover, low or high human pressure, and low or high climate change impact. Available layers of tree cover and threats were used to determine the levels of fragmentation and direct human pressure. Maxent niche modelling with two Global Circulation Models helped determining climate change impact by the 2050s.

Results

When all 80 species are considered, in total, 59% of the ERSs are threatened by little tree cover or high human pressure. When climate change is also considered, then 71‐73% of the ERSs are threatened. When an increased risk of extirpation of populations outside protected areas is considered, then 84–86% of the ERSs are threatened. Seven species warrant special attention because all their ERSs are threatened across their whole distribution in South America: Balfourondendron riedelianum, Cariniana legalis, Dalbergia nigra, Handroanthus pulcherrimus, Pachira quintana, Prosopis flexuosa, and Prosopis pallida.

Conclusions

Our results confirm the urgency to set up a regional action plan for the conservation of tree genetic resources in South America. With this threat assessment, we aim to support governments and organizations who are taking up this task.
  相似文献   

17.
为探讨毛竹(Phyllostachys edulis)入侵对周围森林群落的影响,作者于2005-2011年在天目山自然保护区进行了7年长期定位观测实验,研究了毛竹入侵地森林群落的植物物种多样性变化.结果表明:毛竹入侵对周围森林群落植物物种多样性产生了不利影响:毛竹林乔木层和灌木层植物的Simpson指数小于针阔混交林和毛竹-针阔混交林,而草本层的Simpson指数则大于针阔混交林和毛竹-针阔混交林.植物物种丰富度、Simpson指数和Pielou均匀度指数随时间发生了较大变化:毛竹入侵的森林群落其乔木层和灌木层的物种丰富度、Simpson指数和Pielou均匀度指数显著降低(P<0.05),草本层的物种丰富度显著提高(P<0.05),Simpson指数和Pielou均匀度指数未表现出明显的变化.毛竹-针阔混交林去除毛竹后,乔木层和灌木层物种丰富度和Simpson指数增加,草本层物种丰富度、Simpson指数和Pielou均匀度指数明显下降.可见,毛竹入侵使森林群落植物多样性发生实质性的变化,对自然保护区植物群落造成了重大影响.由此可见,要使保护区物种多样性得到保护,除进行科学的管理外,还需要控制毛竹蔓延.  相似文献   

18.
Plant pathogens in irrigation water were recognized early in the last century as a significant crop health issue. This issue has increased greatly in scope and degree of impact since that time and it will continue to be a problem as agriculture increasingly depends on the use of recycled water. Plant pathogens detected from water resources include 17 species of Phytophthora, 26 of Pythium, 27 genera of fungi, 8 species of bacteria, 10 viruses, and 13 species of plant parasitic nematodes. There is substantial evidence demonstrating that contaminated irrigation water is a primary, if not the sole, source of inoculum for Phytophthora diseases of numerous nursery, fruit, and vegetable crops. These findings pose great challenges and opportunities to the plant pathology community. A variety of water treatment methods are available but few have been assessed for agricultural purposes under commercial conditions. Investigations into their technical feasibility and economics are urgently needed. Aquatic ecology of plant pathogens is an emerging field of research that holds great promise for developing ecologically based water decontamination and other strategies of pathogen mitigation. Pathogen detection and monitoring as well as biological and economic thresholds are much-needed IPM tools and should be priorities of future research. Teaming with hydrologists, agricultural engineers, ecologists, geneticists, economists, statisticians, and farmers is essential to effectively attack such a complex issue of growing global importance. Research should proceed in conjunction with nutrient and pesticide management studies in a coordinated and comprehensive approach as they are interrelated components of water resource conservation and protection.  相似文献   

19.
湘潭锰矿区植物资源调查及超富集植物筛选   总被引:4,自引:0,他引:4  
通过设置样地,对湘潭锰矿区的植物资源进行了全面调查。结果表明:锰矿区植物丰富,共有28科,53种,植物以自然定居种为主,少见人工栽培种;生活史以多年生植物为主,少见1年生植物。群落结构上,以草灌丛为主,少见乔木种;当前锰矿区形成的以多年生草灌丛为主的局部群落,是原锰矿区植被在开采中被彻底破坏后,处在逐步向亚热带常绿阔叶林演替的一种初级阶段;其次,对矿区植物锰富集能力进行的分析表明,植物各组织(根、茎、叶)之间锰富集量差异明显,大部分物种地下部分锰含量大于地上部分,表现出一般植物的共性,只有少部分植物地上部分锰含量大于地下部分,表现出其特殊性;此外,植物种之间富集锰能力差异显著;莎草地上与地下部分锰含量均大于超富集植物10000mg.kg-1的临界浓度且富集系数与转移系数均大于1的超富集植物评价标准,表明其具有超强的富集锰能力。调查还发现,位于中-高锰矿区莎草生物量高达507.06g.m-2,符合超富集植物应具有较高生物量的标准。可见,莎草可作为中-高锰污染区生态修复的首先超富集植物种。  相似文献   

20.
湖北省原生台湾杉资源及其保护   总被引:1,自引:0,他引:1  
杨琴军  徐辉  严志国  刘毅  赵凯歌  陈龙清   《广西植物》2006,26(5):551-556
台湾杉为国家二级重点保护野生植物,现间断分布于我国长江以南少数几个省市及缅甸北部。作者在野外调查基础上,分析了湖北省台湾杉的地理分布特点、母树资源现状、种群数量和结构、群落特征、濒危原因并提出了保护建议。结果表明湖北省共有野生分布的台湾杉约40株,约90%以上为胸径在25cm以上的大树,主要零星分布于星斗山保护区海拔750~1000m的沟谷或山坡;种群年龄结构极不完整,处于严重衰退过程之中;群落类型多样,次生性较强,反映了台湾杉是在人类的长期干扰下勉强生存的。导致台湾杉濒危的主要原因有历史时期气候变迁导致台湾杉分布区大幅度缩小和居群数量剧烈下降;台湾杉遗传质退化,种子发芽率低,天然更新能力差;残遗居群多为小种群,结构不合理,种群退化严重;人为干扰和破坏加速了台湾杉的灭亡。根据台湾杉濒危的原因和现状,建议加强对台湾杉原生居群和单株的保护,逐步恢复生境,改善种群结构。  相似文献   

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