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1.
Cormac J. O’Callaghan Sandra Irwin Kenneth A. Byrne John O’Halloran 《Biodiversity and Conservation》2017,26(13):3103-3124
The continued decline of natural forests globally has increased interest in the potential of planted forests to support biodiversity. Here, we examine the potential conservation benefits of plantation forests from an Irish perspective, a country where remaining natural forests are fragmented and degraded, and the majority of the forest area is comprised of non-native Sitka spruce (Picea sitchensis (Bong.) Carr.) and Norway spruce (Picea abies (L.) Karst.) plantations. We examine the true value of Irish plantation forests to native biodiversity, relative to remaining natural forest fragments, and to prior and alternative land use to afforestation. We find that plantation forests provide a suitable surrogate habitat primarily for generalist species, as well as providing habitat for certain species of conservation concern. However, we find that plantation forests provide poor habitat for native forest specialists, and examine potential management strategies which may be employed to improve habitat provision services for this group. 相似文献
2.
SAM RIFFELL JAKE VERSCHUYL DARREN MILLER T. BENTLY WIGLEY 《Global Change Biology Bioenergy》2011,3(4):313-321
Short‐rotation woody cropping (SRWC) refers to silvicultural systems designed to produce woody biomass using short harvest cycles (1–15 years), intensive silvicultural techniques, high‐yielding varieties, and often coppice regeneration. Recent emphasis on alternatives to fossil fuels has spurred interest in producing SRWC on privately owned and intensively managed forests of North America. We examined potential bird and small mammal response at the stand level to conversion of existing, intensively managed forests to SRWCs using meta‐analysis of existing studies. We found 257 effect sizes for birds (243 effect sizes) and mammals (14 effect sizes) from 8 studies involving Populus spp. plantations. Diversity and abundance of bird guilds were lower on short‐rotation plantations compared with reference woodlands, while abundance of individual bird species was more variable and not consistently higher or lower on SRWC plantations. Shrub‐associated birds were more abundant on SRWC plantations, but forest‐associated and cavity‐nesting birds were less abundant. Effects on birds appeared to decrease with age of the SRWC plantation, but plantation age was also confounded with variation in the type of reference forest used for comparison. Both guilds and species of mammals were less abundant on SRWC plantations. These conclusions are tentative because none of these studies directly compared SRWC plantations to intensively managed forests. Plantations of SRWCs could contribute to overall landscape diversity in forest‐dominated landscapes by providing shrubby habitat structure for nonforest species. However, extensive conversion of mature or intensively managed forests to SRWC would likely decrease overall diversity, especially if they replace habitat types of high conservation value. 相似文献
3.
The spatial distribution of birds and carabid beetles in pine plantation forests: the role of landscape composition and structure 总被引:2,自引:0,他引:2
Luc Barbaro Jean-Pierre Rossi Fabrice Vetillard Julien Nezan Hervé Jactel 《Journal of Biogeography》2007,34(4):652-664
Aim To evaluate the joint and independent effects of spatial location, landscape composition and landscape structure on the distribution patterns of bird and carabid beetle assemblages in a mosaic landscape dominated by pine plantation forests. Location A continuous 3000‐ha landscape mosaic with native maritime pine Pinus pinaster plantations of different ages, deciduous woodlands and open habitats, located in the Landes de Gascogne forest of south‐western France. Methods We sampled breeding birds by 20‐min point counts and carabid beetles by pitfall trapping using a systematic grid sampling of 200 points every 400 m over the whole landscape. Explanatory variables were composed of three data sets derived from GIS habitat mapping: (1) spatial variables (polynomial terms of geographical coordinates of samples), (2) landscape composition as the percentage cover of the six main habitats, and (3) landscape structure metrics including indices of fragmentation and spatial heterogeneity. We used canonical correspondence analysis with variance partitioning to evaluate the joint and independent effects of the three sets of variables on the ordination of species assemblages. Moran's I correlograms and Mantel tests were used to assess for spatial structure in species distribution and relationships with separate landscape attributes. Results Landscape composition was the main factor explaining the distribution patterns of birds and carabids at the mesoscale of 400 × 400 m. Independent effects of spatial variables and landscape structure were still significant for bird assemblages once landscape composition was controlled for, but not for carabid assemblages. Spatial distributions of birds and carabids were primarily influenced by the amount of heathlands, young pine plantations, herbaceous firebreaks and deciduous woodlands. Deciduous woodland species had positive responses to edge density, while open habitat species were positively associated with mean patch area. Main conclusions Forest birds were favoured by an increase in deciduous woodland cover and landscape heterogeneity, but there was no evidence for a similar effect on carabid beetles. Fragmentation of open habitats negatively affected both early‐successional birds and carabids, specialist species being restricted to large heathlands and young plantations. Several birds of conservation concern were associated with mosaics of woodlands and grasslands, especially meadows and firebreaks. Conserving biodiversity in mosaic plantation landscapes could be achieved by the maintenance of a significant amount of early‐successional habitats and deciduous woodland patches within a conifer plantation matrix. 相似文献
4.
Inge van Halder Luc Barbaro Emmanuel Corcket Hervé Jactel 《Biodiversity and Conservation》2008,17(5):1149-1169
While the area of plantation forests continues to increase worldwide, their contribution to the conservation of biodiversity
is still controversial. There is a particular concern on the central role played by natural habitat remnants embedded within
the plantation matrix in conserving species-rich insect communities. We surveyed butterflies in maritime pine plantation landscapes
in south-western France in 83 plots belonging to seven habitat types (five successional stages of pine stands, native deciduous
woodlands and herbaceous firebreaks). The effect of plot, habitat and landscape attributes on butterfly species richness,
community composition and individual species were analysed with a General Linear Model (GLM), partial Canonical Correspondence
Analysis (CCA) and the IndVal method. The most important factors determining butterfly diversity and community composition
were the presence of semi-natural habitats (deciduous woodlands and firebreaks) at the landscape scale and the composition
of understorey vegetation at the plot scale. Pure effects of plot variables explained the largest part of community variation
(12.8%), but landscape factors explained an additional, independent part (6.7%). Firebreaks were characterized by a higher
species richness and both firebreaks and deciduous woodlands harboured species not or rarely found in pine stands. Despite
the forest-dominated landscape, typical forest butterflies were rare and mainly found in the deciduous woodlands. Threatened
species, such as Coenonympha oedippus and Euphydryas aurinia, were found in pine stands and in firebreaks, but were more abundant in the latter. In the studied plantation forest, the
conservation of butterflies depends mainly on the preservation of semi-natural habitats, an adequate understorey management
and the maintenance of soil moisture levels. 相似文献
5.
Plantation forests generally support lower bird diversity than natural forests. However, in some instances the plantations have been found to provide suitable habitat for a number of bird species. In the Eastern Arc Mountains, there is limited knowledge how understorey birds, some of which make seasonal altitudinal movements, use plantations. Using mist netting we assessed seasonal use of the plantation forest by the understorey bird community in Bunduki Forest Reserve in the Uluguru Mountains. Species diversity and capture rates were significantly higher during the cold season than during the hot season possibly due to seasonal altitudinal migration by some species. The use of plantations by those species that make seasonal altitudinal movements shows that plantation forests can enhance indigenous biodiversity by enabling connectivity between two or more natural forest patches. Our findings suggest that in a situation where there is no natural forest, an exotic plantation with suitable indigenous understorey cover can help in protection of birds, including endemic and near-endemic species. 相似文献
6.
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
7.
Summary The detrimental effects of conifer plantations on open ground habitats have been well catalogued and discussed, but the potential contribution of planted forests to the conservation of woodland biodiversity has not been quantified to the same extent. This quantification is needed urgently to help forest managers fulfil commitments to biodiversity enhancement as outlined in the UK Biodiversity Action Plan, the UK Forestry Standard and the UK Woodland Assurance Scheme (UKWAS). Results are presented from a five-year programme of research aimed at obtaining baseline information on biodiversity in planted forests and evaluating the contribution of planted forests to the conservation of native flora and fauna. Fifty-two plots were surveyed in total, covering a range of different tree crops (Scots pine Pinus sylvestris L., Sitka spruce Picea sitchensis (Bong.) Carr., Norway spruce Picea abies L. and Corsican pine Pinus nigra var maritima (Aitón) Melville) and stand ages (pre-thicket, mid-rotation, mature and over-mature) in three contrasting bioclimatic zones (upland, foothills and lowlands) throughout Britain. Additional plots were established in semi-natural woodland to allow comparisons between the biodiversity of plantations and native stands. Over 2000 species were recorded in total, including 45 Red Data Book species. Planted stands had similar or richer fungal and invertebrate communities to those of the native stands but poorer lichen and vascular plant communities. The latter were strongly affected by shading, dense, mid-rotation Sitka spruce stands having the lowest species counts. In contrast, these stands had a high diversity of mycorrhizal fungi, including a number of rare and threatened species normally associated with native pine wood. Bryophyte species-richness was related more to climate than woodland type, with the wetter upland spruce and native oak stands having the most diverse communities. Compared to the younger planted stands, over-mature planted stands had a higher proportion of species characteristic of semi-natural woodland stands. This related to greater structural diversity and higher deadwood volumes in the over-mature stands. It is concluded that conifer plantations make a positive contribution to biodiversity conservation in the UK and hence to the UK Biodiversity Action Plan. No single stand or crop type provides ‘optimal’ conditions for biodiversity, but the habitat value of plantations could be enhanced by increasing the area managed under alternative systems to clear-felling, such as ‘continuous cover’ and/or non-intervention natural reserves. 相似文献
8.
Paul R. Lintott Nils Bunnefeld Elisa Fuentes-Montemayor Jeroen Minderman Lorna M. Blackmore Dave Goulson Kirsty J. Park 《Biodiversity and Conservation》2014,23(11):2875-2901
Urban expansion threatens global biodiversity through the destruction of natural and semi-natural habitats and increased levels of disturbance. Whilst woodlands in urban areas may reduce the impact of urbanisation on biodiversity, they are often subject to under or over-management and consist of small, fragmented patches which may be isolated. Effective management strategies for urban woodland require an understanding of the ecology and habitat requirements of all relevant taxa. Yet, little is known of how invertebrate, and in particular moth, assemblages utilise urban woodland despite being commonly found within the urban landscape. Here we show that the abundance, species richness, and species diversity of moth assemblages found within urban woodlands are determined by woodland vegetation character, patch configuration and the surrounding landscape. In general, mature broadleaved woodlands supported the highest abundance and diversity of moths. Large compact woodlands with proportionally less edge exposed to the surrounding matrix were associated with higher moth abundance than small complex woodlands. Woodland vegetation characteristics were more important than the surrounding landscape, suggesting that management at a local scale to ensure provision of good quality habitat may be relatively more important for moth populations than improving habitat connectivity across the urban matrix. Our results show that the planting of broadleaved woodlands, retaining mature trees and minimising woodland fragmentation will be beneficial for moth assemblages. 相似文献
9.
Oisín F. McD. Sweeney Mark W. Wilson Sandra Irwin Thomas C. Kelly John O’Halloran 《Biodiversity and Conservation》2010,19(8):2329-2342
This study compared the bird assemblages of native semi-natural woodlands and non-native Sitka spruce (Picea sitchensis) plantations in Ireland to identify what vegetation variables most influenced birds and to identify management targets in
plantations to maximise future bird conservation. Point counts were conducted in 10 Oak (Quercus spp.) and 10 Ash (Fraxinus excelsior) native woodlands and in five Mid-rotation (20–30 years old) and five Mature (30–50 years old) Sitka spruce plantations.
Ordination was used to characterise woodland types according to their constituent bird species. Total bird density (calculated
using Distance software) and species richness were assessed for the different woodland types. Oak and Ash woodland bird assemblages were
separated from Mid-rotation and Mature plantations by the ordination. There was no difference in total bird density between
any of the woodland types. Oak woodlands had significantly higher species richness than either Mid-rotation or Mature Sitka
spruce plantations. Ash had higher species richness than Mature Sitka spruce plantations. Understorey vegetation was negatively
associated with total bird density, which also varied with survey year. Understorey vegetation was positively associated with
species richness. Reasons for the relationships between vegetation and bird assemblages are discussed. Management should seek
to increase shrub and understorey vegetation in the Mid-rotation phase to improve the contribution of plantations to bird
conservation. 相似文献
10.
11.
Stephen M. Pawson Eckehard G. Brockerhoff Esther D. Meenken Raphael K. Didham 《Biodiversity and Conservation》2008,17(5):1127-1148
The once extensive native forests of New Zealand’s central North Island are heavily fragmented, and the scattered remnants
are now surrounded by a matrix of exotic pastoral grasslands and Pinus radiata plantation forests. The importance of these exotic habitats for native biodiversity is poorly understood. This study examines
the utilisation of exotic plantation forests by native beetles in a heavily modified landscape. The diversity of selected
beetle taxa was compared at multiple distances across edge gradients between each of the six possible combinations of adjacent
pastoral, plantation, clearfell and native forest land-use types. Estimated species richness (Michaelis–Menten) was greater
in production habitats than native forest; however this was largely due to the absence of exotic species in native forest.
Beetle relative abundance was highest in clearfell-harvested areas, mainly due to colonisation by open-habitat, disturbance-adapted
species. More importantly, though, of all the non-native habitats sampled, beetle species composition in mature P. radiata was most similar to native forest. Understanding the influence of key environmental factors and stand level management is
important for enhancing biodiversity values within the landscape. Native habitat proximity was the most significant environmental
correlate of beetle community composition, highlighting the importance of retaining native remnants within plantation landscapes.
The proportion of exotic beetles was consistently low in mature plantation stands, however it increased in pasture sites at
increasing distances from native forest. These results suggest that exotic plantation forests may provide important alternative
habitat for native forest beetles in landscapes with a low proportion of native forest cover. 相似文献
12.
Pablo Corcuera Pedro Luis Valverde José Alejandro Zavala-Hurtado Gabriela De la Rosa César Gabriel-Durán 《Journal of Insect Conservation》2010,14(6):711-719
Eucalyptus spp. are commonly planted, forming non-native plantations, including the tropics and their wildlife conservation value is
relatively unknown. Recent studies have concluded that secondary forests and tree plantations are less diverse than well-developed
tropical rain forests. However, introduced Eucalyptus stands harbored similar species richness to surrounding native woodland in temperate woodlands in North America though the
identity of the species present may differ. Species composition, as well as dominance curves and differences in community
structure add additional insight to understanding faunistic responses to replacement of native woodland by Eucalyptus plantations. Here, we compared species richness, diversity patterns, and the distribution of non-weaving spiders between
native woodlands and Eucalyptus plantations in a temperate region of Mexico. We found more Lycosidae species in all plantation stands. Other community attributes were not consistently different between plantations and native
woodlands. This is explained by similarities between, and differences within, the understory of the two main vegetation types.
Multivariate analyses identified three spider groups and five spider species could be identified as indicators of these groups.
A comparison of the number of species of the wandering spiders between the two vegetation types suggests a compensation pattern
that is reported here for the first time. 相似文献
13.
Industrial timber plantations severely impact biodiversity in Southeast Asia. Forest fragments survive within plantations, but their conservation value in highly deforested landscapes in Southeast Asia is poorly understood. In this study, we compared bird assemblages in acacia plantations and fragmented forests in South Sumatra to evaluate each habitat’s potential conservation value. To clarify the impact of habitat change, we also analyzed the response of feeding guild composition. Five habitat types were studied: large logged forest (LLF), burnt logged forest (BLF), remnant logged forest (RLF), 4-year-old acacia plantation (AP4), and 1-year-old acacia plantation (AP1). Estimated species richness (Chao 2) was highest in LLF then AP4 and BLF, while AP1 and RLF had lower estimated species richness. Community composition was roughly divided into two groups by non-metric multidimensional scaling ordination: acacia plantation and logged forest. Sallying substrate-gleaning insectivores, such as drongos, broadbills, and some flycatchers, were restricted to LLF, whereas acacia plantation hosted many terrestrial frugivores, such as doves. Although fragmented forests in our study site lacked several common tropical forest species, these fragments provide an important habitat for some sallying and terrestrial insectivores. A network of small riparian remnant forests could be a complementary habitat for some species, while the conservation value of burnt forest might be low. In conclusion, the highly fragmented forests in plantations are suboptimal habitats for birds but are still very important, because large primary forest blocks have been nearly lost in the surrounding landscape. 相似文献
14.
Passive woodland regeneration following cropland abandonment and pine plantations are two major approaches for vegetation
restoration in agricultural landscapes in the Mediterranean Basin. We compared the effects of these two contrasting approaches
on local bird density in central Spain on the basis of species characteristics, including regional density, habitat breadth,
life-history traits and plumage colouration. Local bird density increased with regional density and habitat breadth in both
woodland and pine plantation plots following macroecological patterns of bird abundance and distribution. In woodlands, dichromatic
species were more abundant than monochromatic species and bird density increased with the intensity of territory defense and
as the proportion of plumage colour generated by pheomelanin decreased. Contrary to our prediction, this latter observation
suggests that woodlands may induce higher levels of physiological stress in birds than pine plantations even though these
represent a novel habitat change. In pine plantations, sedentary species were more abundant than migratory species and bird
density was negatively related to body and egg mass. These traits of bird species in pine plantations are characteristic of
successful invaders. The variation in bird density explained by phylogeny was twice as high in pine plantations as in woodlands,
suggesting that pine plantations limit accessibility to some clades. Our results support, from an evolutionary perspective,
the described inability of pine plantations on cropland to maintain or increase bird diversity in Mediterranean agricultural
landscapes. 相似文献
15.
P. Angelini R. Compagno A. Arcangeli G. Bistocchi M. L. Gargano R. Venanzoni 《Plant biosystems》2016,150(3):540-549
The macrofungal species richness and community assemblages in Italian native woodlands of oaks and Carpinus betulus and non-native woodlands of Pinus spp., Cupressus sempervirens and Eucalyptus camaldulensis were examined through the collection of basidiomata and ascomata over 1 year. The sampling in Collestrada (Umbria) and Pizzo Manolfo (Sicily) forests revealed 216 species of macrofungi. The results indicate differences in macromycete richness and diversity patterns between the two sites. The dominant tree species of the two sites were different; thus, the Collestrada forests had higher mycorrhizal species richness, while the Pizzo Manolfo forest had a higher relative number of saprotroph macrofungi. The macrofungal community of Quercus frainetto woodland from Collestrada forest was richer and more diverse than the other site's woodland types. This study highlighted that both Collestrada and Pizzo Manolfo forests provide a habitat for diverse macrofungal species, not in the least ectomycorrhizal species. 相似文献
16.
Aura M. Alonso-Rodríguez Bryan Finegan Konrad Fiedler 《Biodiversity and Conservation》2017,26(10):2295-2326
Oil palm is one of the most rapidly expanding crops throughout the tropics, yet little is known about its impacts on Neotropical invertebrate biodiversity. Responses of insect assemblages to land conversion may substantially vary among taxa. We assessed geometrid and arctiine moth assemblages in a Costa Rican human dominated landscape, where oil palm plantations are now the second most common land cover. Moths were sampled during 6 months with automatic traps in the interior and margin of old-growth forests, young secondary forests and oil palm plantations in a 30 km2 area. Our results show that richness and diversity of both taxa were severely reduced in oil palm compared to all other habitats. Geometrid abundance was highest in forest interiors and lowest in oil palm, while arctiine numbers did not differ between habitats. Dominance was highest in oil palm plantations, where one arctiine species and one geometrid species accounted for over 40% of total abundance in each of their respective taxa. Species composition was distinct in oil palm and forest interior sites, and depicted a gradient of habitat disturbance in ordination space that was strongly related to vegetation diversity and structure. This study demonstrates that oil palm plantations are not a suitable habitat for these moth taxa. Whilst some arctiine species seem adapted to disturbed habitats, geometrids were more dependent on old-growth forests, showing higher bioindicator potential. In the face of accelerated oil palm expansion, conservation strategies should focus on protecting old-growth forest remnants, as well as increasing species diversity and structural complexity of degraded habitats. 相似文献
17.
In the face of the continuing destruction of tropical rainforests, a major challenge is to understand the consequences of these habitat changes for biodiversity and the time scale at which biodiversity can recover after such disturbances. In this study, we assessed the patterns in communities of birds among forests of varying age consisting of clear-cuts of former coniferous plantations, selectively logged compartments and primary forests in Kibale National Park, Uganda. Birds were surveyed by 10-minute point counts at 174 randomly located points in nine forest areas during September–October 2011. A total of 2 688 birds representing 115 species were recorded. The species density, diversity and dominance of all birds, and dominance of forest specialists showed no differences between forest areas, whereas the species density and diversity of forest specialists differed significantly between forest areas. The composition of communities of all birds and of forest specialists varied significantly among the forest areas. Our results show that even after 19 and 43 years, respectively, communities of birds in clear-cuts of former coniferous plantations and selectively logged forests have not fully recovered from the disturbances of logging, highlighting the need to preserve primary forests for conservation of birds. 相似文献
18.
Deborah Faria Mateus Luís Barradas Paciencia Marianna Dixo Rudi Ricardo Laps Julio Baumgarten 《Biodiversity and Conservation》2007,16(8):2335-2357
The traditional shade cacao plantations (cabrucas) of southern Bahia, Brazil, are biologically rich habitats, encompassing
many forest-dwelling species. However, a critical question for the conservation management of this specific region, and the
highly fragmented Atlantic forest in general, is to what extent the conservation value of cabrucas relies on the presence
of primary forest habitat in the landscape. We investigated the relative importance of cabrucas and forests for the conservation
of five diverse biological groups (ferns, frogs, lizards, birds and bats) in two contrasting landscapes in southern Bahia,
one dominated by forest with some interspersed cabrucas, and one dominated by cabrucas with interspersed forest fragments.
The community structure (richness, abundance and diversity) of all biological groups differed between cabrucas and forests,
although these differences varied among groups. A high number of forest species was found in the cabrucas. However, there
were pronounced differences between the two landscapes with regard to the ability of cabrucas to maintain species richness.
Irrespective of the biological group considered, cabrucas located in the landscape with few and small forest fragments supported
impoverished assemblages compared to cabrucas located in the landscape with high forest cover. This suggests that a greater
extent of native forest in the landscape positively influences the species richness of cabrucas. In the landscape with few
small forest fragments interspersed into extensive areas of shade cacao plantations, the beta diversity of birds was higher
than in the more forested landscape, suggesting that forest specialist species that rarely ventured into cabrucas were randomly
lost from the fragments. These results stress both the importance and the vulnerability of the small forest patches remaining
in landscapes dominated by shade plantations. They also point to the need to preserve sufficient areas of primary habitat
even in landscapes where land use practices are generally favorable to the conservation of biodiversity. 相似文献
19.
为探索天然林和橡胶林蜘蛛多样性现状,于2010年8月在海南黎母山自然保护区选取天然林和橡胶林,采用扫网法、陷阱法和单位面积法收集蜘蛛标本,分析两种林型之间蜘蛛组成、多样性和功能群差异,并以蜘蛛科和数量分布为属性进行主成分分析(PCA),探讨林型中样方之间蜘蛛群落的相似性。共采集蜘蛛标本3609头,用于统计分析的成蛛969头,归属于23科,162种。天然林20科,100种,优势类群为跳蛛科、球蛛科和园蛛科;橡胶林17科,87种,优势类群为肖蛸蛛科、狼蛛科和猫蛛科。从蜘蛛的数量分布看,橡胶林蜘蛛个体密度显著高于天然林;而天然林多样性指数和丰富度指数显著高于橡胶林。橡胶林中结圆网型和游猎型蜘蛛显著高于天然林,结皿网型显著低于天然林,伏击型不存在显著性差异。PCA分析结果表明,24个样方趋于分成天然林和橡胶林2组,并且天然林样方之间相似性极高,而橡胶林样方之间相似性相对较低。以上结果表明:(1)橡胶林替代天然林后蜘蛛群落结构发生变化,多样性降低;(2)增加生境结构的复杂性和减少人为干扰对保护和恢复物种多样性有重要意义。 相似文献
20.
Christine N. Meynard Mauricio Soto-Gamboa Paul A. Heady III Winifred F. Frick 《Biodiversity and Conservation》2014,23(8):1949-1963
Forestry plantations represent about 4 % of the global land cover and demand for wood is steadily increasing worldwide. Impacts of forest plantations on biodiversity are controversial; forest plantations could positively influence biodiversity by producing a buffer zone between native forests and agriculture, while replacement of native forests with plantations could reduce biodiversity. Chile is one of the main producers of wood worldwide, and production is largely based on intensively managed monocultures of exotic tree species. Only a few studies have looked at the effects of forestry plantations on biodiversity in Chile, mainly focusing on pine plantations. The aim of this study was to characterize habitat use and richness of bats between native forests, eucalyptus plantations and grasslands in a biodiversity hotspot in southern Chile to determine how land use affects an important mammalian taxa. We found no difference in use or richness of bats in eucalyptus plantations versus native forests. Regional context within the larger Valdivian watershed (Andes, central valley, coastal range) had a stronger influence on bat activity and richness than land use type (native forest, plantation, grassland), with the Andean region being the most diverse and where most bat activity is concentrated. Our results suggest that the composition and structure of the surrounding landscape mosaic may be fundamental to determine the impacts of forestry and human land use on biodiversity. 相似文献