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1.
Summary Machair is a complex dune grassland habitat confined to Scotland and Ireland. With two-thirds of the world area of machair in Scotland, the UK has a special responsibility for this resource, and the UK Machair Habitat Action Plan identifies a range of realistic management targets and actions aimed at protecting and enhancing the habitat. Machair's conservation importance is substantially reliant on active, traditional management, but quantitative and location-based information on management is rarely available, and this will have an impact on any numerical targets in the Plan. Though progress has been made on many of the actions, further measurable progress will very much depend, not only on improvements in the information base, but also in the understanding of relationships between land use and biodiversity. Progress to date on actions and targets is evaluated, and problems are identified. 相似文献
2.
Summary Stipitate hydnoid (‘tooth’) fungi are considered to be threatened throughout much of central and northern Europe. In response to concern about the status of these fungi in the UK, a Biodiversity Action Plan has been developed for 14 species in this group. As a first step towards implementation of this plan, a number of surveys have been initiated, to determine the current status and distribution of hydnoid fungi. An overview of the results of these surveys is described. A series of distribution maps are presented, based on a compilation of early records and the results of a recent field survey in Scottish coniferous forests. The difficulties of interpreting early records are discussed, with particular reference to the taxonomie confusion that has surrounded this group of fungi. Although available data provide little evidence for decline of hydnoid fungi, a number of species display very restricted distributions within Scotland. The recent discovery of several species new to Britain emphasises the need for further field surveys to define the current status of these fungi with greater accuracy. 相似文献
3.
Summary A morphologically distinct variety of Athyrium distentifolium called A. distentifolium var. flexile has been found only in Scotland. Research was undertaken for aUK Biodiversity Action Plan. To confirm that this taxon has a definitely recognisable morphology, a morphometric analysis was used on the range of characters used to define this variety. It showed that it can be clearly differentiated. 相似文献
4.
Fred J. Rumsey Johannes Chr. Vogel Stephen J. Russell John A. Barrett Mary Gibby 《Plant Ecology & Diversity》2013,6(1):37-47
Summary The Killarney Fern (Trichomanes speciosum) was considered amongst the rarest and most vulnerable of Europe's plants. Research which fed into the Biodiversity Action Plan and developed alongside it, has forced us to reconsider the level of threat to this species. A hitherto overlooked stage of the life-cycle, the gametophyte, has been shown to be comparatively abundant, genetically diverse, largely threat-free and with the potential over time to regenerate the familiar sporophyte stage. This research also promoted wider public interest which itself generated additional records, such that even the sporophyte is now known at more British sites than at any time previously and the species is accordingly considered ‘recovered’. However, continued legal protection and the need for further research are still recommended. 相似文献
5.
Summary All forests, including commercial plantations, provide a range of habitats for conserving and enhancing elements of native biodiversity. However, the biodiversity values of commercial plantations will depend on the management practices adopted on site, as well as the landscape context of the plantation. The present study describes a generic, quantitative method for assessing the potential biodiversity benefits that might be derived from a plantation, depending on the management practices adopted. This method is based on existing ecological design and management principles. The Plantation Biodiversity Benefits Score (PBBS) was designed to be repeatable and practical to apply. The method can be used either as a stand-alone tool or as part of an integrated framework to assess and compare the commercial and environmental benefits that can be derived from different layouts, management practices and locations of plantations anywhere in Australia. 相似文献
6.
The Grey Partridge Perdix perdix is a European Species of Conservation Concern and a priority species under the UK Biodiversity Action Plan. The Game & Wildlife Conservation Trust (GWCT) launched a major programme to help partridge recovery in the UK, built on the GWCT’s Partridge Count Scheme (PCS) and including a demonstration site from 2002. We contrast the national picture of no population change since 1999 from BTO monitoring with a doubling of spring pair density on PCS sites. At the demonstration site, where set‐aside was used for habitat creation, Grey Partridge breeding density increased six‐fold, to 18 pairs/km2, then fell back. The drop coincided with bad weather but also with the disappearance of rotational set‐aside when the set‐aside rate fell to zero, which halved the amount of brood‐rearing habitat. Non‐rotational set‐aside remained unchanged, as did the amount of nesting habitat that it provided. Grey Partridge density was significantly linked to rotational set‐aside, especially wild bird cover, but not to non‐rotational set‐aside. The demonstration project also showed that, with appropriate precautions, it was possible to shoot over 60% of Red‐legged Partridges Alectoris rufa while maintaining Grey Partridge losses below 5%. On PCS sites, the annual change in spring density in recent years differed in relation to neither shooting pressure nor intensity of Red‐legged Partridge releasing. Provision of brood‐rearing habitats and game cover increased with the latter, and probably counteracts the shooting losses of Grey Partridges on Red‐legged Partridge shoots when, as on PCS sites, active measures keep those losses below 20%. Targeted personal advice channelled through the PCS has been fundamental to these successes and must be expanded. 相似文献
7.
RICHARD A. ENNOS RAJ WHITLOCK MICHAEL F. FAY BARBARA JONES LINDA E. NEAVES ROBIN PAYNE IAN TAYLOR NATASHA DE VERE PETER M. HOLLINGSWORTH 《Botanical journal of the Linnean Society. Linnean Society of London》2012,168(2):194-203
Many endemic plant species belong to taxonomically complex groups. These endemics have often arisen as a consequence of recent and rapid evolutionary divergence facilitated by processes such as hybridization, polyploidy and/or breeding system transitions. The rapid and dynamic nature of divergence in taxonomically complex groups leads to problems in the implementation of traditional species‐based approaches for the conservation of the biodiversity that they contain. Firstly, the taxa of interest can be difficult to define and identify, leading to practical difficulties in implementing conservation measures. Secondly, a species‐based approach often fails to capture the complexity of diversity present in the taxonomically complex group. To accommodate these challenges, we have developed a Process‐Based Species Action Plan approach. This is designed to conserve the processes leading to the generation of biodiversity, rather than focusing on the preservation of individual named taxa. We illustrate the approach using a group of endemic tree species (Sorbus) on the Scottish island of Arran that have originated via a combination of multiple recent hybridization events and apomixis. The plan focuses on the optimization of habitat management to ensure the reproduction and regeneration of Sorbus in the zone in which these evolutionary processes operate, and to facilitate hybridization that will ensure the continued generation of diversity in this group. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 168 , 194–203. 相似文献
8.
Euphrasia species in Britain attract a large amount of conservation attention due to the recognition of numerous endemic taxa in what is essentially a species‐poor flora. To develop a set of research tools to investigate the evolutionary processes underlying this diversification, a membrane enrichment procedure has been used to isolate five polymorphic microsatellite loci from Euphrasia nemorosa (Pers.) Wallr. These loci amplify polymorphic products in several other British Euphrasia species. 相似文献
9.
Summary Members of the genus Hygrocybe are ubiquitous and colourful components of many undisturbed and nutrient-poor grasslands in the UK. Through a number of detailed surveys of the distribution of Hygrocybe spp. and of genera showing similar patterns of occurrence (e.g. Clavaria spp., Entoloma spp., Geoglossum spp.) a picture is gradually emerging of the more important ‘waxcap grassland’ sites, and of those species in greatest need of protection. Waxcap fungi are far from ideal experimental organisms which explains why so little has been published about their biology and ecology. They cannot be cultured on laboratory media and the correct conditions for inducing spores of most species to germinate have yet to be established. Nevertheless approaches such as isotope ratio mass spectrometry and the use of molecular biology techniques are beginning to provide an insight into the role played by these organisms in grassland ecosystems, and why they are so adversely affected by many agricultural practices. Current field experiments at various sites including Sourhope near Kelso will also permit investigations into waxcap ecology to be correlated with parallel studies of other members of the soil biota. 相似文献
10.
C.C. Wilcock 《Plant Ecology & Diversity》2013,6(1):121-131
Summary Populations of rare clonally spreading species are increasingly being shown to be composed of one or a few genotypes. Clones have potentially unlimited life but two factors, genetic erosion due to random events and increasing accumulation of genetic load in older genotypes, combine to expose them to sexual failure and loss of fertility. Non-breeding clonal populations are at risk of extinction because they lack the ability to adapt or escape from changing environments. Twinflower (Linnaea borealis L.) has been lost from nearly 50 % of its pre-1970 sites. It is a clonal self-incompatible plant and sexual failure has been reported from Canada, Britain and Scandinavia. Sexual failure is due to high levels of within-clone pollination by flies. Seed set occurs naturally in Scottish populations which have some genetic diversity. A non-breeding population in Scotland has been restored to viability by experimental cross-pollination with pollen from a distant source. Conservation action for this species should therefore be directed to the prevention of loss of habitat and restoration of population viability by translocation of compatible mates. Translocating plants into extant, but non-breeding, populations are still a matter of debate and are frequently opposed. However, experimental translocations must now be performed to establish whether intervention can secure the long-term survival of rare clonal plants without the constant need for re-introduction. 相似文献
11.
F. Bekkaoui R. S. S. Datla M. Pilon T. E. Tautorus W. L. Crosby D. I. Dunstan 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1990,79(3):353-359
Summary Protoplasts from suspension cultures of somatic embryos of white spruce (Picea glauca Moench Voss) were electroporated with plasmids containing the chimeric genes for chloramphenicol acetyl transferase (CAT) or -glucuronidase (GUS), under control of one of three promoters. Transient CAT gene expression of approximately equal magnitude resulted when the CAT gene was fused to either the cauliflower mosaic virus (CaMV) 35S promoter or the nopaline synthase (NOS) promoter. When the CAT gene was fused to a tandem repeat CaMV 35S promoter (pPBI-363), CAT enzyme activity compared to NOS or 35S promoters increased up to eightfold (cell line WS-34), and were up to 100-fold greater than control (electroporated without plasmid). Comparatively, protoplasts of black spruce (Picea mariana Mill) and jack pine (Pinus banksiana Lamb.), electroporated with pPBI-363, produced increases in CAT activity compared to control of 90-fold and 70-fold, respectively. White spruce (WS-34) protoplasts were subsequently electroporated with the GUS gene fused to the tandem repeat CaMV 35S promoter. Comparatively, GUS enzyme activity increased up to tenfold compared to GUS fused to a CaMV 35S promoter. The results indicated that transient expression of the CAT and GUS genes was influenced by the type of promoter and cell line used, as well as by electroporation conditions.NRCC No. 30498 相似文献
12.
13.
FREDERICK J. RUMSEY JOHANNES C. VOGEL STEPHEN J. RUSSELL JOHN A. BARRETT MARY GIBBY 《Biological journal of the Linnean Society. Linnean Society of London》1999,66(3):333-344
Genetic diversity in the Killarney fern, Trichomanes speciosum Willd. has been investigated in south-western Scotland, the northern-most limit of the distribution of the sporophyte. T. speciosum is unique amongst European pteridophytes in that both phases of the life cycle are perennial and capable of vegetative propagation. Within sites no variation was revealed by allozyme electrophoresis, even where both generations were growing together. In contrast, diversity was observed among sites, with seven different multilocus phenotypes (MLPs) present in the area. Two of these MLPs covered large areas while the others were restricted to one, or few localities. Asexual reproduction of the gametophyte via gemmae is assumed to be the main means of dispersal in recent times, allowing single clones to become widespread, while the overall genetic variability may be attributed to sexual reproduction and spore dispersal in historic times under more favourable climatic conditions. We suggest that it is not inbreeding, nor lack of genetic variation that limits sporophyte production, but rather the prevailing climatic conditions. The sporophyte is extremely rare and vulnerable. However, when the gametophyte is considered, the species is neither threatened with extinction, nor does it appear to face the danger of marked genetic erosion, because the long-lived gametophyte stage contains all of the genetic variability present in the area and can be regarded as a valuable 'seed-bank'. 相似文献
14.
Summary The distribution of microfilament bundles (MFBs) in the primary tissues ofChamaecyparis obtusa roots has been investigated by electron microscopy. Nomarski differential interference-contrast (NDIC) images of MFBs in sections of embedded materials are also presented to complement the ultrastructural observations. The peripheral phloem parenchyma cells, also known as precursory phloem, generally possess greater numbers of MFBs than do any other cell type. MFBs are apparently absent in the cortical, meristematic or root cap tissues. The number of MFBs seen in a transection of a cell varies according to its position in the ontogenetic sequence. While all the MFBs in peripheral phloem parenchyma cells lie within 2.0 m from and on occasion contact the plasmamembrane, some MFBs in other phloem and xylem cells are located in the central areas of the cytoplasm. The possible three-dimensional distribution of MFBs in a streaming peripheral phlowm parenchyma cell is discussed. 相似文献
15.
生物多样性的熵值结构 总被引:3,自引:0,他引:3
多样性一般定义为生物进化过程中物种表现型的丰富程度。从广义上讲,生物进化与环境归类作用的结构复杂性对生物为多样性的解释是很有益处的。我们认为区域水平与样地水平上的气候归类型与植被归类型是最基本的划分因子,本文以中国东北部黑龙江省的山地植被为例,采用多等级熵值分配的方法来证明所使用的方法。我们得出气候归类型与植被归类型所占有的熵值成分要弱于物种表现型丰富度所占有的熵值成份。值得注意的是其相对的熵值贡献率对每一个因子的最大熵值的变化规律。分析结果表明气候归类型占有较低的熵值而植被归类型占有较高的熵值。因此仅仅以在区域气候型为主要指标所划分的物种生态位是不够的,而以小区域内的植被型为指标所产生的物种生态位具有较高利用价值。 相似文献
16.
Shih-Ming Kao 《Ocean Development & International Law》2013,44(1):2-16
This article examines the National Plans of Action (NPOAs) adopted by selected States to combat illegal, unreported, and unregulated (IUU) fishing. Despite some minor differences between States’ NPOAs, the NPOAs generally are similar to what was envisioned in the International Plan of Action to Prevent, Deter, and Eliminate Illegal, Unreported, and Unregulated Fishing adopted in 2001. 相似文献
17.
"国际生物多样性观察年"(IBOY)介绍 总被引:2,自引:1,他引:1
“国际生物多样性观察年”(IBOY)是由DIVERSITAS所筹划的旨在对全球生物多样性现状从不同层次进行综合研究的一项计划。该计划的主要目标包括:促进公众对生物多样性现状和未来的了解、促进生物多样性学科的发展和完善以及为政府决策过程提供科学依据。DIVERSITAS试图通过该项计划,了解我们所面临的全球性生物多样性现状、全球生物多样性丧失的程度及其原因、生物多样性的丧失给人类生活所带来的威胁、我们怎样保护和发展生物多样性这一人类共同的财富以及探索评估全球生物多样性现状的手段等方面的问题。本文同时还对实施“国际生物多样性观察年”计划所提出的一些提议进行了简要介绍。 相似文献
18.
ALON WARBURG JAMES MONTOYA-LERMA CONSUELO JARAMILLO ANA LUISA CRUZ-RUIZ KATHERINE OSTROVSKA 《Medical and veterinary entomology》1991,5(1):9-16
Potential vectors of Leishmania braziliensis Vianna were assessed at four study sites in the mountainous Valle del Cauca, western Colombia, from March to June 1989. In an active focus of transmission at 1450 m altitude, a coffee plantation at Versalles, there were high densities of antropophilic phlebotomines: Lutzomyia columbiana (Ritorcelli & Van Ty) and Lu.townsendi (Ortiz), both in the verrucarum species group, and of Lu.pia (Fairchild & Hertig). At a comparable altitude in a forest reserve at Yotoco where leishmaniasis is unknown, Lu.pia was the prevalent species and Lu.townsendi was absent. In two localities at 1150 m altitude, there were plentiful Lu.lichyi (Floch & Abonnenc) plus both species in the verrucarum group, but Lu.pia was absent. One of these localities, a coffee plantation at Villa Hermosa where a leishmaniasis outbreak occurred in 1986, was compared with a leishmaniasis-free, partly wooded nature reserve at Mateguadua. No natural infections of Leishmania were found in a total of 1896 wild-caught female phlebotomines belonging to at least seven species. It remains unclear why Leishmaniasis transmission is associated with coffee plantations in this part of Colombia. Laboratory-bred Lu.lichyi females were invariably autogenous, and blood-seeking females of this species were always parous. Parity rates in wild-caught females of other species were 55% Lu.pia, 24% Lu.columbiana and 14% Lu.townsendi. Female Lutzomyia infected artificially with Le.braziliensis promastigotes developed peripylarian infections. Higher proportions of Lu.townsendi (96%) and Lu.columbiana (78%) became infected but these species developed lower rates of stomodaeal infections (P less than 0.1) than Lu.lichyi (37%) or Lu.pia (44%).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
19.
“2020年后全球生物多样性框架”是当前《生物多样性公约》谈判的焦点议题, 了解该议题的谈判进展将对我国顺利举办第15次缔约方大会(COP15)产生积极的作用。本文在梳理相关谈判进程的基础上, 分析了各方主要观点, 并就我国应对国际谈判并以东道国身份推进该框架的制定进程提出了建议。各方对制定框架的时间表、程序和一般性原则形成了较为一致的共识, 认为应尽快确定“2020年后全球生物多样性框架”的程序及时间表, 基于“爱知生物多样性目标”的执行经验、科学结论和和广泛的信息来源, 与“可持续发展目标”及其他国际进程衔接, 重视利用情景和模型, 并支持更多利益相关方参与制定过程。同时, 各方认为框架应主要包括土地利用、保护和恢复生物多样性的措施、解决生物多样性丧失的根本原因、主流化、能力建设、资源调动、国家承诺等要素。为应对国际谈判, 建议我国在《公约》谈判会议中适时提出以下观点: 重视实现可持续利用相关的目标; 提升评估指标体系的合理性; 科学制定措施。此外, 建议我国采取以下措施积极推进框架制定进程: 充分利用国际高级别会议, 提升政治重视程度; 积极与主要国际进程协作, 推进该框架深入讨论; 重视调动利益相关方积极性。 相似文献