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31.
The karst landform in southern China is renowned for its high levels of species diversity and endemism. Globally, karst ecosystems are under threat from unsustainable anthropogenic disturbance and climate changes and are among the most threatened ecosystems worldwide. In this study, we used the typical karst endemic genus in southern China, Primulina Hance, as a model to identify areas within the karst landform with high diversity and to investigate congruence between phylogenetic and species‐based measures of diversity. Using phylogenetic information and species distribution data, we measured geographical patterns of diversity with four metrics: species richness (SR), corrected weighted endemism (CWE), phylogenetic diversity (PD), and phylogenetic endemism (PE). Our results revealed a high spatial congruence among SR, PD, and PE, with hotspot areas identified in the Nanling Mountains (i.e., north Guangdong and northeast Guangxi) and southeast Yungui Plateau (i.e., north and southwest Guangxi), whereas the hotspots of CWE are comparatively uniform throughout the geographic extent. The categorical analysis of neo‐ and paleoendemism identified a pattern of mixed neo‐ and paleoendemism in numerous grid cells, suggesting that karst areas in southern China have acted as both “museums” and “cradles” of plant evolution. Conservation gap analysis of hotspots revealed that the majority of prioritized hotspots (>90%) of the genus are outside of protected areas, therefore indicating the limited effectiveness of national nature reserves for the karst flora. Overall, our results suggest that the karst flora merits more conservation attention and SR can be an effective surrogate to capture PD in conservation planning.  相似文献   
32.
Egyptian flower mantis Blepharopsis mendica (Order: Mantodea) is a widespread mantis species throughout the southwest Palearctic region. The ecological and geographical distribution of such interesting species is rarely known. So, through this work, habitat suitability models for its distribution through Egyptian territory were created using MaxEnt software from 90 occurrence records. One topographic (altitude) and eleven bioclimatic variables influencing the species distribution were selected to generate the models. The predicted distribution in Egypt was focused on the Delta, South Sinai, the north-eastern part of the country, and some areas in the west including Siwa Oasis. Temporal analysis between the two periods (1900–1961) and (1961–2017) show current reduction of this species distribution through Delta and its surrounding areas, may be due to urbanization. On the other hand, it increases in newly protected areas of South Sinai. Under the future climate change scenario, the MaxEnt model predicted the habitat gains for B. mendica in RCP 2.6 for 2070 and loss of habitat in RCP 8.5 for the same year. Our results can be used as a basis for conserving this species not only in Egypt, but also throughout the whole of its range, also, it show how the using of geo-information could help in studying animal ecology.  相似文献   
33.
Abstract

Biodiversity data generated in the context of research projects often lack a strategy for long-term preservation and availability, and are therefore at risk of becoming outdated and finally lost. The reBiND project aims to develop an efficient and well-documented workflow for rescuing such data sets. The workflow consists of phases for data transformation into contemporary standards, data validation, storage in a native XML database, and data publishing in international biodiversity networks. It has been developed and tested using the example of collection and observational data but is flexible enough to be transferred to other data types and domains.  相似文献   
34.
Abstract

According to advances in phytogeographic knowledge, a revision of boundaries for the Italian Ecoregions have been made. Main changes relate to the southern and eastern limits between Temperate and Mediterranean Divisions. The revision triggered a comprehensive update of Ecoregions for an improved support to biodiversity and sustainable management initiatives.  相似文献   
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36.
Abstract

Throughout the world, forest covers one-third of the land's area. Present and historical human activities caused tremendous land use changes and triggered the onset of unseen climate changes. Yet, these socio-economically based environmental changes interfere with services that forests provide to mankind from global to local scales. Densely populated regions such as Flanders (Belgium), with over 430 people per km2, have the dubious honour to serve as examples of extreme human induced forest changes. The issue of forest biodiversity is reviewed in the light of the Millennium Ecosystem Assessment scheme. Flanders is a poorly forested region (11% forest cover); supporting services are consequently low. Merely 16% of that area has known 230 years of continuous forest cover, representing forest with the highest current biodiversity. Also, the demands for regulating services are growing and the limits may have been reached. Provisioning services may increase again in future when demands for, for example bio-energy, increase. Cultural services, particularly the recreational function, have increased greatly. Human well-being in Flanders partly depends on the services provided by forest ecosystems. However, as demands on forests are huge, a shift to a sustainable use of forest resources will be essential to assure its beneficial role for present and future generations.  相似文献   
37.
In many parts of the world, plantations make up a considerable proportion of the total forest area. In such regions, the identification of high biodiversity value stands and of management practices to enhance biodiversity is essential if the goals of Sustainable Forest Management are to be achieved. Since complete biodiversity assessments are rarely possible, efforts have been increasingly focussed on the use of indicators. Of particular interest are indicators applicable to individual stands that require no specialist taxonomic or technical knowledge to assess. Candidate biodiversity indicators had been identified in a previous study using data from Irish Sitka spruce (Picea sitchensis) and ash (Fraxinus excelsior) plantations but had yet to be tested on independent data. In the present study, the provisional indicators for vascular plant, bryophyte, spider and bird diversity were tested on data from Irish Scots pine (Pinus sylvestris), oak (Quercus petraea/Quercus robur), Sitka spruce and lodgepole pine (Pinus contorta) plantations. Conifer canopy cover was confirmed as an important biodiversity indicator, due to its influence on below-canopy microclimatic and structural conditions. Bryophyte species richness was higher in relatively high canopy cover plantations on poorly drained soils, while bird species richness was higher in more open plantations with high shrub cover. Coarse woody debris was an important substrate for forest-associated bryophytes, with higher species richness at higher volumes of deadwood. Both proximity to old woodland and stand age were confirmed as positive indicators for forest-associated vascular plants. This is related to dispersal limitation in these species, with nearby woodlands acting as important seed sources and colonisation increasing with time. Stand age was also confirmed as a positive indicator for forest-associated spiders and is related to the development of suitable habitat as the plantation matures. All of the confirmed indicators can be assessed without need for specialist knowledge, are ecologically meaningful and applicable to a range of forests managed under a clearfelling system. They can be used to assess the potential value of stands for the taxonomic groups to which they apply, as well as giving insights into management practices to enhance diversity in these groups.  相似文献   
38.
Several longer-term assembly studies on ex-arable land have found that species that arrive first at a disturbed site can play a key role in the further development of the community and that this priority effect influences aboveground productivity, species diversity and stability of the grassland communities that develop. Restoration of nutrient poor, species rich grasslands is often limited by seed dispersal as well as the accessibility of suitable microsites for establishment. Sowing species (i.e. creating priority effects for further assembly) may help overcome such dispersal barriers, but the potential of using priority effects for restoration has not been tested in this type of dry grassland. We tested the hypothesis that sowing two different seed mixtures used for dry acidic grassland restoration onto a sandy substrate (which formed an equivalent to a primary succession) would create priority effects, and that these priority effects would be sustained over a number of years. We followed community assembly and measured aboveground productivity for four years after sowing. We found that priority effects caused by sowing of differently diverse mixtures did also occur in dry acidic grassland habitat, but that how persistent they were over time depended on the response variable considered. Priority effects on species number were not as strong as found in previous ex-arable land studies, whereas priority effects for aboveground productivity were still visible after 4 years. In addition, functional composition of the community still reflected the composition of the seed mixtures 4 years later. Our results suggest that priority effects can occur in nutrient-poor dry acidic grassland but in contrast to more nutrient-rich sites the breadth of responses affected may not be as wide.  相似文献   
39.
Since the pre-historic era, humans have been using forests as a food, drugs and handcraft reservoir. Today, the use of botanical raw material to produce pharmaceuticals, herbal remedies, teas, spirits, cosmetics, sweets, dietary supplements, special industrial compounds and crude materials constitute an important global resource in terms of healthcare and economy. In recent years, DNA barcoding has been suggested as a useful molecular technique to complement traditional taxonomic expertise for fast species identification and biodiversity inventories. In this study, in situ application of DNA barcodes was tested on a selected group of forest tree species with the aim of contributing to the identification, conservation and trade control of these valuable plant resources.The “core barcode” for land plants (rbcL, matK, and trnH-psbA) was tested on 68 tree specimens (24 taxa). Universality of the method, ease of data retrieval and correct species assignment using sequence character states, presence of DNA barcoding gaps and GenBank discrimination assessment were evaluated. The markers showed different prospects of reliable applicability. RbcL and trnH-psbA displayed 100% amplification and sequencing success, while matK did not amplify in some plant groups. The majority of species had a single haplotype. The trnH-psbA region showed the highest genetic variability, but in most cases the high intraspecific sequence divergence revealed the absence of a clear DNA barcoding gap. We also faced an important limitation because the taxonomic coverage of the public reference database is incomplete. Overall, species identification success was 66.7%.This work illustrates current limitations in the applicability of DNA barcoding to taxonomic forest surveys. These difficulties urge for an improvement of technical protocols and an increase of the number of sequences and taxa in public databases.  相似文献   
40.
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