首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 390 毫秒
1.
One of the serious environmental problems since the 1980s has been the conflict between the high rate of deforestation and maintenance of healthy ecosystem services and biological values in tropical forests. There is an urgent demand for setting up an appropriate environmental assessment to keep healthy ecosystem functions and biodiversity along with sustainable forest use based on ecology. In this study, we tried to assess logging-disturbance effects on the abundances of several flying insect groups (higher-taxon approach) in lowland tropical rain forest (Deramakot Forest Reserve, Sabah, Malaysia), while considering seasonal changes and vertical forest stratification. The season was the most important factor affecting the abundances of all the insect groups. Effects of logging disturbance were prominent in the understorey but obscure in the canopy. Changes in physical conditions caused by logging—possibly an increased evaporation due to solar radiation—may have decreased the abundance of desiccation-sensitive insects, especially in the understorey. There are also two probable reasons for the difference between events in the understorey and those in the canopy: (1) noise effects of various physical, environmental factors may have obscured insect responses to logging disturbance in the canopy; (2) higher spatio-temporal variation in quality and quantity of living food resources—such as leaves, flowers and fruits—provided in the canopy may have affected the abundance of their consumer insects independently of logging disturbance. Thus, this study suggests that the abundance of some insect groups at higher-taxon level, especially in the understorey, can be used as bioindicators for assessing effects of logging disturbance on the forest ecosystem.  相似文献   

2.
Over the last four decades the world has been losing biodiversity at an alarming rate despite the increasing number of protected areas (PAs). Certified forest management may complement the role of PAs in protecting biodiversity. Forest certification aims to promote sustainable forest management and to maintain or enhance the conservation value of certified forests. The area of forest under certified forest management has grown quickly over the past decade. Forest Stewardship Council (FSC) certification, for example, currently covers 148 million hectares, i.e., 3.7 % of the world’s forests. In spite of such increase there is, however, a dearth of information on how forest certification is related to biodiversity. In this study we assessed if FSC certification is being applied in high biodiversity areas in cork oak savannas in Portugal by comparing biodiversity values of certified and non-certified areas for birds, reptiles and amphibians. We calculated the relative species richness and irreplaceability value for each group of species in certified and non-certified areas and compared them using randomization tests. The biodiversity value of certified areas was not significantly greater than that of non-certified areas. Since FSC certification is expanding quickly in cork oak savannas it is important to consider the biodiversity value of these areas during this process. Prioritizing areas of high biodiversity value would enhance the conservation value of forest certification and facilitate integrating certification with other conservation initiatives.  相似文献   

3.
We examine existing and developing approaches to balance biodiversity conservation and timber production with the changing conservation roles of federal and nonfederal forest land ownerships in the US Pacific Northwest. At landscape scales, implementation of the reserve-matrix approach of the federal Northwest Forest Plan in 1994 was followed by proposals of alternative designs to better integrate disturbance regimes or to conserve biodiversity in landscapes of predominantly young forests through active management without reserves. At stand scales, landowners can improve habitat heterogeneity through a host of conventional and alternative silvicultural techniques. There are no state rules that explicitly require biodiversity conservation on nonfederal lands in the region. However, state forest practices rules require retention of structural legacies to enhance habitat complexity and establishment of riparian management areas to conserve aquatic ecosystems. Habitat Conservation Plans (HCPs) under the US Endangered Species Act provide regulatory incentives for nonfederal landowners to protect threatened and endangered species. A state-wide programmatic HCP has recently emerged as a multi-species conservation approach on nonfederal lands. Among voluntary incentives, the Forest Stewardship Council certification comprehensively addresses fundamental elements of biodiversity conservation; however, its tough conservation requirements may limit its coverage to relatively small land areas. Future changes in landscape management strategies on federal lands may occur without coordination with nonfederal landowners because of the differences in regulatory and voluntary incentives between ownerships. This raises concerns when potentially reduced protections on federal lands are proposed, and the capacity of the remaining landscape to compensate has been degraded.  相似文献   

4.
We examined the effect of selective logging and corresponding forest canopy loss on arboreal ant diversity in a tropical rainforest. Arboreal ants were collected from an unlogged forest plot and from forest plots selectively logged 14 years and 24 years earlier in Danum Valley, Sabah, Malaysia, using a canopy fogging method. Selective logging was associated with a significant decrease in canopy cover and an increase in understory vegetation density relative to unlogged forest. Our study showed that selective logging in primary forest might not dramatically decrease total species number and overall abundance of arboreal ants; however, it may influence the species composition and dominance structure of the ant community, accompanied by an increase in abundance of shrub‐layer species and trophobiotic species. In view of the results of this study, management techniques that minimize logging impact on understory vegetation structure are likely to help maintain the conservation value of logged forests for arboreal ants. Our results also suggest that accurate assessment of the impacts on biodiversity should not be based only on measurement of species number and overall abundance, but also on analysis of species composition and community structure.  相似文献   

5.
We examine existing and developing approaches to balance biodiversity conservation and timber production with the changing conservation roles of federal and nonfederal forest land ownerships in the US Pacific Northwest. At landscape scales, implementation of the reserve-matrix approach of the federal Northwest Forest Plan in 1994 was followed by proposals of alternative designs to better integrate disturbance regimes or to conserve biodiversity in landscapes of predominantly young forests through active management without reserves. At stand scales, landowners can improve habitat heterogeneity through a host of conventional and alternative silvicultural techniques. There are no state rules that explicitly require biodiversity conservation on nonfederal lands in the region. However, state forest practices rules require retention of structural legacies to enhance habitat complexity and establishment of riparian management areas to conserve aquatic ecosystems. Habitat Conservation Plans (HCPs) under the US Endangered Species Act provide regulatory incentives for nonfederal landowners to protect threatened and endangered species. A state-wide programmatic HCP has recently emerged as a multi-species conservation approach on nonfederal lands. Among voluntary incentives, the Forest Stewardship Council certification comprehensively addresses fundamental elements of biodiversity conservation; however, its tough conservation requirements may limit its coverage to relatively small land areas. Future changes in landscape management strategies on federal lands may occur without coordination with nonfederal landowners because of the differences in regulatory and voluntary incentives between ownerships. This raises concerns when potentially reduced protections on federal lands are proposed, and the capacity of the remaining landscape to compensate has been degraded. This paper was previously published in Biodiversity and Conservation, Volume 16(13) under doi:  相似文献   

6.
Open woodlands are among the biologically richest habitats of the temperate zone. Although open woodlands were much more common in the past and covered large areas of Europe, their original cover and magnitude of their loss remain mostly unknown. Here, we quantify the loss of open woodlands and assess the potential for their restoration in an internationally protected biodiversity hot-spot, floodplain woodlands of lower Thaya and March rivers of Dolní Morava UNESCO Biosphere Reserve in Czech Republic. Aerial photographs from years 1938 and 2009 were used to analyse changes in forest canopy closure across an area of 146 km2 and separately for 270 ha of nature reserves found in the area. Forestry maps and aerial photographs were used to analyse changes in forest age structure. Between 1938 and 2009, expansion of closed-canopy forest reduced open woodlands cover from 41% to 5.7% of total wooded area, or 68.5% to 14.1% in the state reserves respectively. Logging has led to a decrease in mature forest cover from 45% to 26% between 1990 and 2009. State reserves prevented logging, but not open woodlands loss. The magnitude of open woodlands loss parallels that of tropical habitats, but has gone unabated by nature conservation. Opportunities to restore open woodlands and conserve associated biodiversity in the internationally protected (e.g. UNESCO, Natura 2000), mostly state-owned, woodlands are being compromised by rapid logging. Our results also point to the low efficiency of international conservation measures in post-communist members of European Union.  相似文献   

7.
An intensive camera-trapping study and a nutrient analysis were carried out to understand how natural licks are important for mammals in inland tropical rain forests where soil cations are usually depleted. Using camera traps, we investigated the fauna, food habits, and the frequency of visitation by species at five natural licks in the Deramakot forest reserve, Sabah, Malaysia. All food-habit types of mammals (carnivore, herbivore-frugivore, insectivore, and omnivore), which included 29 (78.4%) of 37 species known in Deramakot, were recorded at the natural licks. The sambar deer, followed by the bearded pig, the lesser mouse-deer, the Malay badger, and the orangutan were the most commonly recorded species and represented 77.5% in terms of the frequency of appearance in all photographs taken throughout the year. These results indicated that, although the proportion of species recorded at the natural licks relative to the whole mammalian fauna of the forest was high, the frequency of visitation greatly varied among the species, and only a few species dominated. The frequency of visitation seemed to reflect both the density of species and the demand for the minerals, because some endangered, low-density species were more frequently recorded by cameras than expected—for example, the orangutan which was one of the top five species among natural-lick users. The natural licks with greater concentrations of minerals in seepage soil water were significantly preferred by the sambar deer and the bearded pig than those with lower concentrations of minerals. This result suggests that the chemical properties of soil water in natural licks determine the frequency of visitation of these herbivorous species that have strong demand for minerals.  相似文献   

8.
Protected areas such as forest reserves are often assumed to be best ways to conserve biodiversity and maintain intact ecosystems. We examined woody plant composition and diversity in the gallery forest and savannah woodland habitats of Amurum Forest Reserve and areas immediately surrounding it in Jos, Nigeria. A total of 100 10 × 10 m sample plots were established inside and outside the reserve. All woody plants ≥1 cm diameter at breast height (dbh) were identified and measured. A total of 7,564 individual plants categorized as 134 species from 44 families were recorded. Overall species diversity was significantly higher in the Forest Reserve than outside the reserve, although more species were encountered outside the reserve. Our findings suggest that, protected areas and the areas surrounding them are important for the conservation of biodiversity as the areas outside protected areas also contain species of conservation value. The continuous degrading areas outside protected areas isolates them and poses a serious threat to the long‐term viability of wildlife populations, so it is important that biodiversity in protected areas and their surrounding areas be conserved.  相似文献   

9.
林业活动和森林片断化对甲虫多样性的影响及保护对策   总被引:7,自引:3,他引:4  
森林片断化是造成生物多样性丧失的主要原因之一,而林业活动是导致森林片断化的重要因素,同时也在森林恢复中起重要作用。本文从小尺度、局域尺度以及生物地理尺度(大尺度)3个生态尺度分析林业活动和森林片断化对甲虫多样性的影响。在小尺度下,林业活动能够通过改变森林生境或微生境的类型和特性而影响甲虫物种分布。在局域尺度下,林业活动(尤其是森林砍伐)往往能提高许多甲虫类群(如步甲)的物种丰富度(α多样性),这主要与来自周围环境物种扩散以及保留了若干耐受新环境能力较强的森林物种有关;然而,对森林生境依赖性很强的特有种受到了森林片断化的负面影响,面临局域种群灭绝的危险。在生物地理尺度下,林业活动(伐木或森林恢复)使森林生境单一化、异质性降低,从而导致对森林生境变化敏感的物种种群数量降低甚至灭绝。基于以上结果,可以归纳出3个基本原则用于指导林业管理,既能保证林业经济收益,又能维持森林生物多样性。首先,保留大面积的原始森林作为特有种的栖息环境基地,为这些物种在将来森林恢复后重新定居提供资源;其次,由于保护区内原始森林面积有限,且所代表的生境类型有限,所以发展依据自然干扰模式的新伐木方法十分必要;最后,依据自然规律(如火灾)进行森林恢复和天然演替,避免森林的单一化,丰富森林生境类型。  相似文献   

10.
Saproxylic beetles constitute a significant proportion of boreal forest biodiversity. However, the long history of timber production in Fennoscandia has significantly reduced the availability of dead wood and is considered a threat to the conservation of saproxylic beetle assemblages. Therefore, since the mid‐1990s dead wood retention in harvested stands has formed an integral part of silvicultural practices. However, the contribution of this biodiversity‐orientated management approach to conserving saproxylic beetle assemblages in boreal forest landscapes that include production forestry remains largely untested. We examined differences in resident saproxylic beetle assemblages among stands under different management in a boreal forest landscape in Central Sweden, and in particular stands managed according to new conservation‐orientated practices. We also investigated the relationship between beetle diversity and forest stand characteristics. Bark of coarse woody debris (CWD) was sieved for beetles in old managed stands, unmanaged nature reserves, and set‐aside areas, and clear‐cut stands harvested according to certification guidelines [new forestry (NF) clear‐cuts]. All stand types contributed significantly to the total diversity of beetles found. While stand size, position, and distance to nearest reserve were unimportant, both the quality and the quantity of CWD in stands contributed significantly to explaining beetle abundance and species richness. This extends the previous findings for red‐listed invertebrates, and shows that heterogeneous substrate quality and a range of management practices are necessary to maintain saproxylic beetle diversity in boreal forest landscapes that include production forestry. The unique abiotic conditions in combination with the abundant and varied CWD associated with NF clear‐cuts form an important component of forest stand heterogeneity for saproxylic beetles. It is thus essential that sufficient, diverse, CWD is retained in managed boreal landscapes to ensure the conservation of boreal saproxylic beetle assemblages.  相似文献   

11.
深圳福田红树林鸟类自然保护区管理策略初探   总被引:12,自引:0,他引:12  
位于深圳经济特区的福田红树林鸟类自然保护区,是城市边缘一块不可多得的生物多样性宝地。面对经济建设的快速发展和市区的不断扩张,福田自然保护区正承受着来自各方面的巨大压力。如何在积极推动保护区立法的同时,通过开放式生物多样性保护管理,主动参与地方经济建设,实现与周边社区、地方政府和各相关社会利益集团结成合作伙伴关系,是本文探讨的重点。  相似文献   

12.
Timber production forests can support diverse ecological communities, but existing conservation strategies fail to maximize this potential. While methods for limiting logging damage and locating biological reserves have been developed, strategies focused on the sequence and arrangement of harvest units are lacking, particularly for situations in which species-specific knowledge is limited. We present a new landscape-level approach to forest conservation that anticipates local extinctions and focuses on facilitating re-colonization via strategic spatiotemporal harvest plans (which are informed by species occurrence data only). As a proof of concept, we applied our framework to data from four tropical forest sites and found clear benefits of optimized spatiotemporal harvest plans relative to non-optimized harvest plans (random and three pattern-based plans). Our proposed approach, termed the Optimized Floating Refugia strategy, requires minimal species-specific knowledge and can be used to enhance existing conservation efforts (e.g. biological reserve establishment, reduced-impact logging). The approach effectively prioritizes logging-sensitive habitat specialists with restricted ranges and thus provides the largest benefits to the most extinction-prone species. This simple but novel method shows promise as a general strategy to improve biodiversity conservation in species-rich production forest landscapes.  相似文献   

13.
In an earlier special issue of this journal, Marsh & Greer summarized forest land use in Sabah at that time and gave an introduction to the Danum Valley Conservation Area. Since that assessment, during the period 1990-2010, the forests of Sabah and particularly those of the ca 10 000 km(2) concession managed on behalf of the State by Yayasan Sabah (the Sabah Foundation) have been subject to continual, industrial harvesting, including the premature re-logging of extensive tracts of previously only once-logged forest and large-scale conversion of natural forests to agricultural plantations. Over the same period, however, significant areas of previously unprotected pristine forest have been formally gazetted as conservation areas, while much of the forest to the north, the south and the east of the Danum Valley Conservation Area (the Ulu Segama and Malua Forest Reserves) has been given added protection and new forest restoration initiatives have been launched. This paper analyses these forest-management and land-use changes in Sabah during the period 1990-2010, with a focus on the Yayasan Sabah Forest Management Area. Important new conservation and forest restoration and rehabilitation initiatives within its borders are given particular emphasis.  相似文献   

14.
This study was carried out in forestland of Camili Biosphere Reserve (CBR) area in NE Turkey. It was designed to evaluate the consequences of disturbances on changes in secondary forest succession from 1985 to 2005 for monitoring forest plant biodiversity changes and developing conservation strategies. The successional stages were mapped using Geographic Information System (GIS), Global Positioning System (GPS), aerial photos and high resolution satellite images (IKONOS). The results showed that stable stage decreased about 77.96% over the last 20-year time period. Although 701.6 ha conifer forests existed in competition and reaction stages in 1985, none existed in 2005. In overall, about 33.23% of the area decreased, 42.36% did not change and 24.41% increased in different seral stages. Consequently, 8.83% of the area decreased as a whole to indicate that the forest has been developing from stable to nudation stage, that is to say, retrogressive succession is going on in the area. Forest structure and its relationship with plant biodiversity along with its changes over time were determined using FRAGSTATS. We also investigated spatio-temporal configuration of six secondary forest successional stages and generated structural diversity measures. These measures revealed that the landscape has been fragmented, posing a danger to lose the important components of plant biodiversity. Sustainable management of such degraded forests is of crucial importance for plant biodiversity conservation. In conclusion, the study contributes to the development of a framework for effective conservation of plant biodiversity through plant biodiversity integrated Multiple Use Forest Management (MUFM) plans by using the successional stages and plant biodiversity changes.  相似文献   

15.
Kalan Ickes 《Biotropica》2001,33(4):682-690
This study reports extraordinarily high density estimates for the wild pig (Sus scrofa) from an aseasonal tropical forest site within the species'native range. At Pasoh Forest Reserve, a 2500 ha area of lowland dipterocarp rain forest in Peninsular Malaysia, line transects were used to estimate pig density from May to October in 1996 and 1998. In 1996, 44 sightings of S. scrofa consisting of 166 individuals were recorded along 81 km of transects. In 1998, 39 sightings documented 129 individuals along 79.9 km of transects. Estimated population density was 47.0 pigs/km2 in 1996 and 27.0 pigs/km2‐ in 1998. Sus scrofa biomass in this forest was estimated at 1837 kg/km2 and 1346 kg/ km2 in 1996 and 1998, respectively. Differences between years were attributed to changes in the density of young pigs, coincident with a mast‐seeding year of dipterocarp trees in 1996. Pig densities at Pasoh Forest Reserve were much higher than at other forest locations within the species' native range in Europe and Asia. Because Pasoh Forest Reserve is a forest fragment, two factors likely account for the extremely high pig densities: (1) local extinction of natural predators (mainly tigers and leopards) and (2) an abundant year‐round food supply of African oil palm fruits from extensive plantations bordering the reserve.  相似文献   

16.
Landscape and Ecological Engineering - The Innoprise-IKEA (INIKEA) Forest Rehabilitation Project in Kalabakan Forest Reserve, Sabah, was established to rehabilitate degraded forest affected by...  相似文献   

17.
Relatively, little is known about the relationship between biodiversity and ecosystem functioning in forests, especially in the tropics. We describe the Sabah Biodiversity Experiment: a large-scale, long-term field study on the island of Borneo. The project aims at understanding the relationship between tree species diversity and the functioning of lowland dipterocarp rainforest during restoration following selective logging. The experiment is planned to run for several decades (from seed to adult tree), so here we focus on introducing the project and its experimental design and on assessing initial conditions and the potential for restoration of the structure and functioning of the study system, the Malua Forest Reserve. We estimate residual impacts 22 years after selective logging by comparison with an appropriate neighbouring area of primary forest in Danum Valley of similar conditions. There was no difference in the alpha or beta species diversity of transect plots in the two forest types, probably owing to the selective nature of the logging and potential effects of competitive release. However, despite equal total stem density, forest structure differed as expected with a deficit of large trees and a surfeit of saplings in selectively logged areas. These impacts on structure have the potential to influence ecosystem functioning. In particular, above-ground biomass and carbon pools in selectively logged areas were only 60 per cent of those in the primary forest even after 22 years of recovery. Our results establish the initial conditions for the Sabah Biodiversity Experiment and confirm the potential to accelerate restoration by using enrichment planting of dipterocarps to overcome recruitment limitation. What role dipterocarp diversity plays in restoration only will become clear with long-term results.  相似文献   

18.
South East Asia is widely regarded as a centre of threatened biodiversity owing to extensive logging and forest conversion to agriculture. In particular, forests degraded by repeated rounds of intensive logging are viewed as having little conservation value and are afforded meagre protection from conversion to oil palm. Here, we determine the biological value of such heavily degraded forests by comparing leaf-litter ant communities in unlogged (natural) and twice-logged forests in Sabah, Borneo. We accounted for impacts of logging on habitat heterogeneity by comparing species richness and composition at four nested spatial scales, and examining how species richness was partitioned across the landscape in each habitat. We found that twice-logged forest had fewer species occurrences, lower species richness at small spatial scales and altered species composition compared with natural forests. However, over 80 per cent of species found in unlogged forest were detected within twice-logged forest. Moreover, greater species turnover among sites in twice-logged forest resulted in identical species richness between habitats at the largest spatial scale. While two intensive logging cycles have negative impacts on ant communities, these degraded forests clearly provide important habitat for numerous species and preventing their conversion to oil palm and other crops should be a conservation priority.  相似文献   

19.
Isaiah Owiunji 《Ostrich》2013,84(1-2):216-219
Owiunji, I. 2000. Changes in avian communities of Budongo Forest Reserve after 70 years of selective logging. Ostrich 71 (1 & 2): 216–219.

Budongo Forest Reserve, located in the west of Uganda, has been selectively logged for timber for over 70 years, and has a well documented management history. Changes in the avian community, species diversity and relative densities were assessed in two unlogged and three logged and arboricidally treated compartments. Tree-species diversity was highest in the disturbed forest. Over 100 forest bird species were recorded (including a new record for East Africa, Puvel's Illadopsis Illadopsis puveli. Both point counts and mist-netting showed that bird species diversity was higher in the logged and treated than in the unlogged forest. Five species had significantly higher densities in logged forest, three species had significantly higher densities in unlogged forest and 14 species showed no significant change in densities. The response of Budongo Forest birds to disturbance was species-specific.  相似文献   

20.
Bitahai Nature Reserve is located in Northwest Yunnan and is the highest elevation and the highest latitude wetland nature reserve in Yunnan Province. Bitahai Nature Reserve is a typical wetland nature reserve in very low latitude and high elevation with large areas of coniferous forest around the alpine till lakes, wetland and water area ecosystem while compared with natural reserves distributed same latitude in the world. The area of the reserve distribution is the key area of Transverse Mountain Region. It was a refuge for plant and wildlife because Transverse Mountains were not covered by ice in the Tertiary. And the area is now regarded as a center of forming new species and preserving ancient species. Species biodiversity is high and the distribution of some endemic animals and plants are limited in Transverse Mountains area. In the nature reserve, there are many first and second grade protected plants and animals listed in Lists of China National Priority Protection Fauna and Flora. All of these are precious materials of genetic diversity. The diversities of the plant community and vegetation contribute to ecosystem diversity. Thus, Bitahai Nature Reserve holds with high conservation value. However, its biodiversity is threatened by different factors and its conservation should be paid great attention.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号