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1.
D. E. ALLEN F.L.S. 《Biological journal of the Linnean Society. Linnean Society of London》1987,32(2):203-212
Concern to protect wild plants began possibly as early as the eighteenth century. The early-Victorian liberal tide brought the first protests at the over-collecting of rarities, but it seemingly needed the shock of the mid-century fern craze to swing botanical opinion to the cause of moderation. Protective legislation and the establishment of sanctuaries thereafter became the twin concerns, but progress was disappointing. Conservation and the creation of reserves, the fruit of ecological thinking, rose to be the dominant aim only after the Second World War. Developments since then have been rapid and substantial. 相似文献
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Dynamic management of crop diversity: From an experimental approach to on-farm conservation 总被引:1,自引:0,他引:1
Enjalbert J Dawson JC Paillard S Rhoné B Rousselle Y Thomas M Goldringer I 《Comptes rendus biologies》2011,334(5-6):458-468
In agricultural systems, biodiversity includes diversity within species and among species and provides many benefits for production, resilience and conservation. This article addresses the effects of a strategy of in situ conservation called dynamic management (DM) on population evolution, adaptation and diversity. Two French DM initiatives are considered, the first one corresponding to an experimental context, the second to an on-farm management. Results from a study over 26 years of experimental DM of bread wheat (Triticum aestivum L.) are first presented, including the evolution of agronomic traits and genetic diversity at neutral and fitness related loci. While this experiment greatly increased scientific knowledge of the effects of natural selection on cultivated populations, it also showed that population conservation cannot rely only on a network of experimental stations. In collaboration with a farmers' network in France, researchers have begun studying the effects of on-farm DM (conservation and selection) on diversity and adaptation. Results from these studies show that on-farm DM is a key element for the long-term conservation and use of agricultural biodiversity. This method of in situ conservation deserves more attention in industrialised countries. 相似文献
3.
Summary Long term set-aside offers an opportunity to create new grasslands which may be visually appealing and valuable for wildlife. These grasslands, whilst not equalling the nature conservation value of old semi-natural grasslands, may have higher value for wildlife than the arable crops and grass leys which they replace. In this paper we compare the nature conservation value of vegetation established by either natural regeneration or by sowing a seed-mixture based on MG5 Cynosurus cristatus — Centaurea nigra grassland on set-aside at two sites in Scotland. The initial results suggest that sown vegetation is generally more botanically diverse than natural regeneration. Sheep grazing resulted in reduced botanical diversity in the sown plots and early cutting, with cuttings removed and aftermath grazing by cattle, resulted in the highest diversity estimates. However, some effects of management treatment were site specific. 相似文献
4.
Krabchi K Lavoie J Coullin P Bronsard M Pellestor F Yan J Drouin R 《Médecine sciences : M/S》2004,20(4):465-473
As a non-isotopic molecular cytogenetic technique, the primed in situ (PRINS) labelling reaction represents a major technological progress achieved in the past decade. It has become a routine technique for the microscopic visualization of specific DNA sequences in cells and nuclei and constitutes a good alternative to the fluorescence in situ hybridization (FISH) procedure. Among the multiple advantages that characterize the PRINS technique, specificity, rapidity, reliability, reproducibility, and cost-effectiveness can be mentioned. PRINS can be in addition associated with other techniques like FISH, indirect immunofluorescence, and nick translation. The most recent developments show the great potential of this technique. Now PRINS can be used to study single-copy genes and, consequently, can be routinely used to investigate deletions associated with microdeletion syndromes. Therefore, the PRINS technique has the potential to become a widely used molecular cytogenetic tool in clinics and research. This short review presents how the PRINS technique contributed to further the understanding of biological phenomena and describes the different possibilities and applications of the PRINS method in several biological and clinical fields (pre-implantation testing, prenatal, constitutional and oncologic genetic diagnosis). 相似文献
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H. JOHN HARVEY 《Biological journal of the Linnean Society. Linnean Society of London》1987,32(2):149-159
The National Trust was founded in 1895 to preserve land and its associated flora, fauna and buildings. The Trust's land holding has since increased to over 220000 ha, of which almost one-third is of high nature conservation value. The protection provided by Trust ownership is particularly important for certain species. In recent years land management for nature conservation has been transferred from volunteers to professional staff and links with other conservation bodies have been developed. A special programme began in 1979 to survey the wildlife of Trust properties. Research is encouraged where it will benefit management. In some areas where traditional management has lapsed the Trust has invested considerable resources into restoring former regimes. 相似文献
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OLE P. OSTERMANN 《Journal of Applied Ecology》1998,35(6):968-973
10.
Markus Bernhardt-R?mermann Hans-J?rg Brauckmann Gabriele Broll Karl-Friedrich Schreiber Peter Poschlod 《Botanica Helvetica》2009,119(2):87-94
The vegetation composition of calcareous grasslands in Central Europe is mainly determined by the applied management treatments
and the nutrient status of the ecosystems, but these factors cannot clearly be separated. Recently several authors reported
a shift in growth-limiting plant nutrients from nitrogen to phosphate. Therefore, we tested the interaction between management
and plant available phosphate in a long-term experiment in Southern Germany with different management treatments applied to
calcareous grassland. We measured mycorrhization rates, which are assumed to be high at low phosphate availability, to explore
the interaction between management, phosphate availability and vegetation composition. By correlating mycorrhization rates
to vegetation and soil data we found that treatments involving nutrient removal show a greater degree of mycorrhization than
treatments leading to nutrient enrichment. According to decreasing suitability for grassland conservation, the six different
management treatments could be ranked as mowing, followed by mulching (twice a year, once a year and every second year), burning
and undisturbed succession. It was shown, that mycorrhizal infection rates (1) can be used to evaluate different management
treatments for their suitability to conserve the initial vegetation composition, and (2) may provide information about the
processes of adaptation to the current management, namely to differences in plant available phosphate. However, as discussed
for the undisturbed succession treatment, it might not be sufficient to look at the degree of mycorrhization only. These are
related to phosphate availability, but to detect adaptation processes to management, the degree of mycorrhization should be
analysed together with plant’s internal nutrient relocation patterns. 相似文献
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H.J. HARVEY 《Biological journal of the Linnean Society. Linnean Society of London》1995,56(S1):231-248
The range and extent of nature conservation interests on land owned by the National Trust are reviewed and the high level of protection which can be afforded to such features is stressed. Some of the threats to such interests are examined and possible conflicts between management for nature conservation and for other Trust objectives are considered. The importance of survey and monitoring are emphasized. It is argued that nature conservationists need to adopt a view of plant communities which recognises their dynamic nature and which accepts the possibility of change. Evidence is reviewed which supports the non-equilibrium state of some communities, the impact of rare events and the importance of life history phenomena. Some possible future directions of nature conservation in the Trust are discussed. 相似文献
13.
This article reviews the current state-of-the-art concerning the functions of the signal processing protein PII in cyanobacteria and plants, with a special focus on evolutionary aspects. We start out with a general introduction to PII proteins, their distribution, and their evolution. We also discuss PII-like proteins and domains, in particular, the similarity between ATP-phosphoribosyltransferase (ATP-PRT) and its PII-like domain and the complex between N-acetyl-l-glutamate kinase (NAGK) and its PII activator protein from oxygenic phototrophs. The structural basis of the function of PII as an ATP/ADP/2-oxoglutarate signal processor is described for Synechococcus elongatus PII. In both cyanobacteria and plants, a major target of PII regulation is NAGK, which catalyzes the committed step of arginine biosynthesis. The common principles of NAGK regulation by PII are outlined. Based on the observation that PII proteins from cyanobacteria and plants can functionally replace each other, the hypothesis that PII-dependent NAGK control was under selective pressure during the evolution of plastids of Chloroplastida and Rhodophyta is tested by bioinformatics approaches. It is noteworthy that two lineages of heterokont algae, diatoms and brown algae, also possess NAGK, albeit lacking PII; their NAGK however appears to have descended from an alphaproteobacterium and not from a cyanobacterium as in plants. We end this article by coming to the conclusion that during the evolution of plastids, PII lost its function in coordinating gene expression through the PipX-NtcA network but preserved its role in nitrogen (arginine) storage metabolism, and subsequently took over the fine-tuned regulation of carbon (fatty acid) storage metabolism, which is important in certain developmental stages of plants. 相似文献
14.
Fire management to combat disease: turning interactions between threats into conservation management
As the number and intensity of threats to biodiversity increase, there is a critical need to investigate interactions between
threats and manage populations accordingly. We ask whether it is possible to reduce the effects of one threat by mitigating
another. We used long-term data for the long-lived resprouter, Xanthorrhoea resinosa Pers., to parameterise an individual-based population model. This plant is currently threatened by adverse fire regimes and
the pathogen Phytophthora cinnamomi. We tested a range of fire and disease scenarios over various time horizons relevant to the population dynamics of the species
and the practicalities of management. While fire does not kill the disease, it does trigger plant demographic responses that
may promote population persistence when disease is present. Population decline is reduced with frequent fires because they
promote the greatest number of germination events, but frequent fires reduce adult stages, which is detrimental in the long
term. Fire suppression is the best action for the non-seedling stages but does not promote recruitment. With disease, frequent
fire produced the highest total population sizes for shorter durations, but for longer durations fire suppression gave the
highest population sizes. When seedlings were excluded, fire suppression was the best action. We conclude that fire management
can play an important role in mitigating threats posed by this disease. The best approach to reducing declines may be to manage
populations across a spatial mosaic in which the sequence of frequent fires and suppression are staggered across patches depending
on the level of disease at the site. 相似文献
15.
This paper addresses the transformation of forest bureaucracy, which has occurred in accordance with a national policy shift from “fence-and-fine” to “participatory” conservation, and its impact on resource users at Gunung Halimun-Salak National Park in Indonesia and analyzes causal relationships between this transformation and its outcome. The research suggests that the mode of conservation governance was transformed through the implementation of new ways of communication and interaction, learning processes and perceptional and behavioral changes. The result of this analysis indicates that while the dominant discourse of participatory conservation assumes a primary importance of satisfying local economic needs for conservation, what should be emphasized is the process of trust-building and learning between frontline staff and local resource users without which the durability of a conservation institution is questionable. The analysis also reveals both challenges and limitations of a trust-building approach: while the approach effectively functions to halt forest degradation, it might not lead to the rehabilitation of forest ecosystem. 相似文献
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JOHN SHEAIL 《Biological journal of the Linnean Society. Linnean Society of London》1987,32(2):171-177
This paper traces the development of the nature protection movement in Britain, focussing on the relationship of the Society for the Promotion of Nature Reserves to those bodies striving to preserve amenity and promote outdoor recreation. Stress is laid on the opportunities presented by post-war reconstruction in the 1940s and the initiatives taken by ecologists. 相似文献
18.
In order to understand the main ecological factors that influence the distribution of mountain vegetation in Azores and to use it as a model for nature conservation, a study on Santa Bárbara Mountain on Terceira Island was performed. A multivariate analysis was done on vegetation data and the abiotic factors governing the vegetation pattern are discussed. The major factors contributing to the observed vegetation patterns are wind exposure, soil water saturation and historical human impacts. The vegetation analysis showed that Azorean Mountain habitats have a high variation of vegetation structure as a result of the habitat heterogeneity and the extreme ecological conditions. Using the co-dominant plants as indicator species, eco-zones are distinguished, characterized by the combination of different ecological–human factors which contribute to the distribution of specific types of natural vegetation communities. The studies of vegetation distribution give important information about the relation between vegetation and landscape that is essential for conservation, restoration proposals and landscape planning. Azores terrestrial Natura 2000 sites are largely dominated by mountain vegetation, therefore this work provides essential background data for the management plans of these sites. 相似文献
19.
L. M. Wedding A. M. Friedlander J. N. Kittinger L. Watling S. D. Gaines M. Bennett S. M. Hardy C. R. Smith 《Proceedings. Biological sciences / The Royal Society》2013,280(1773)
Increases in the demand and price for industrial metals, combined with advances in technological capabilities have now made deep-sea mining more feasible and economically viable. In order to balance economic interests with the conservation of abyssal plain ecosystems, it is becoming increasingly important to develop a systematic approach to spatial management and zoning of the deep sea. Here, we describe an expert-driven systematic conservation planning process applied to inform science-based recommendations to the International Seabed Authority for a system of deep-sea marine protected areas (MPAs) to safeguard biodiversity and ecosystem function in an abyssal Pacific region targeted for nodule mining (e.g. the Clarion–Clipperton fracture zone, CCZ). Our use of geospatial analysis and expert opinion in forming the recommendations allowed us to stratify the proposed network by biophysical gradients, maximize the number of biologically unique seamounts within each subregion, and minimize socioeconomic impacts. The resulting proposal for an MPA network (nine replicate 400 × 400 km MPAs) covers 24% (1 440 000 km2) of the total CCZ planning region and serves as example of swift and pre-emptive conservation planning across an unprecedented area in the deep sea. As pressure from resource extraction increases in the future, the scientific guiding principles outlined in this research can serve as a basis for collaborative international approaches to ocean management. 相似文献
20.
Seamounts shape the topography of all ocean basins and can be hotspots of biological activity in the deep sea. The Census of Marine Life on Seamounts (CenSeam) was a field program that examined seamounts as part of the global Census of Marine Life (CoML) initiative from 2005 to 2010. CenSeam progressed seamount science by collating historical data, collecting new data, undertaking regional and global analyses of seamount biodiversity, mapping species and habitat distributions, challenging established paradigms of seamount ecology, developing new hypotheses, and documenting the impacts of human activities on seamounts. However, because of the large number of seamounts globally, much about the structure, function and connectivity of seamount ecosystems remains unexplored and unknown. Continual, and potentially increasing, threats to seamount resources from fishing and seabed mining are creating a pressing demand for research to inform conservation and management strategies. To meet this need, intensive science effort in the following areas will be needed: 1) Improved physical and biological data; of particular importance is information on seamount location, physical characteristics (e.g. habitat heterogeneity and complexity), more complete and intensive biodiversity inventories, and increased understanding of seamount connectivity and faunal dispersal; 2) New human impact data; these shall encompass better studies on the effects of human activities on seamount ecosystems, as well as monitoring long-term changes in seamount assemblages following impacts (e.g. recovery); 3) Global data repositories; there is a pressing need for more comprehensive fisheries catch and effort data, especially on the high seas, and compilation or maintenance of geological and biodiversity databases that underpin regional and global analyses; 4) Application of support tools in a data-poor environment; conservation and management will have to increasingly rely on predictive modelling techniques, critical evaluation of environmental surrogates as faunal "proxies", and ecological risk assessment. 相似文献