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1.
We studied the impact of debarking of medicinal tree species on the diversity of xylophagous beetles in Lama Forest Reserve, in Lokoli swampy forest and in crop fields surrounded Lokoli forest. A total of 108 interception traps were set up on debarked and nondebarked trees covering nine medicinal plants that are Anogeissus leiocarpa, Dialium guineense, Khaya senegalensis in Lama Forest; Nauclea diderrichii, Ficus trichopoda, Syzygium owariense in swampy forest; and Parkia biglobosa, Bridelia ferruginea, Pterocarpus erinaceus in crop fields. A total of 116 beetle species were collected belonging to 19 coleoptera families with higher xylophagous beetles than predators. Specific richness and individual abundance of xylophagous beetles were significantly higher in crop fields than in forests. Furthermore, in all habitats, debarked-tree species were more attractive to xylophagous beetles than control trees and were significantly more attacked in crop fields than forests. The most vulnerable medicinal trees to debarking were P. biglobosa, D. guineense, F. trichopoda and P. erinaceus. Three groups of indicator insects according to habitat type, debarking and tree species have been distinguished. Our results clearly imply that by exploiting natural resources humans can impact on the abundance and specific richness of xylophagous beetles by modulating their resources.  相似文献   

2.
The mushroom diversity was studied for 14 months in Edo State, southwestern Nigeria. A total of 76 macrofungi tantamount to 333 fruit bodies were encountered, 74% of which were identified and named. The basidiomycetes and members of the family Tricholomataceae were the best represented taxa while species on wood‐based substrates made up 66% of the total mushroom taxa. The monthly mushroom abundance profile, diversity and species richness for each sampled plot correlated with local meteorological factors, age of the sampled sites and distribution of wood‐based substrates. Jaccard, Sorensen and Bray–Curtis similarity index values showed that plots A and D, representing young actively managed and old abandoned rubber tree plantations, respectively, were the most dissimilar in mushroom composition. The hypersensitive response of macrofungal fruit bodies to climate variables qualify mushrooms as veritable biomonitors or bioindicators of climate change. This study supported earlier reports that rubber agroforests are a depauperate pool of utilitarian mushrooms.  相似文献   

3.
Use and conservation preferences for woody savanna species among the Gourounsi people in south-central Burkina Faso were investigated using a new informant-based valuation system. Two hundred informants from 10 villages evaluated the importance of 20 preselected woody species for nine different uses: edible fruits, vegetable sauce, construction, firewood, medicine, commerce, field trees, and conservation. The study identified eight key species: Parkia biglobosa, Vitellaria paradoxa, Tamarindus indica, Adansonia digitata, Vitex doniana, Detarium microcarpum, Bom-bax costatum, and Strychnos spinosa. They all had high commercial and nutritional value. The local knowledge about the selected woody species was similar between men and women, and between young and old, but it differed between villages. The results indicate that knowledge erosion does not take place among the Gourounsi, but considerable local differences exist. Conservation management should focus on the key species, and for these, assisted regeneration, tree planting, and further ecological research is recommended.  相似文献   

4.
The diversity and host associations of parasitoids attacking mycophagous drosophilids were studied in Tokyo (a warm‐temperate region) and Sapporo (a cool‐temperate region) in Japan. Field collections were carried out using traps baited with mushrooms in May, June, September and October 2009 in Tokyo and in July and August 2010 in Sapporo. The major drosophilid species that emerged from mushroom baits was Drosophila bizonata in Tokyo and D. orientacea in Sapporo. In total, 13 parasitoid species emerged from drosophilids occurring in mushroom baits, and 11 of them were larval parasitoids belonging to Braconidae and Figitidae. Among the 11 larval parasitoids, 10 were collected in Tokyo, while only two were collected in Sapporo. It is not known why their diversity differed so much between these two regions. Four of the 11 larval parasitoids have also been recorded from drosophilid larvae occurring in fruit (banana). The use of these two habitats (mushrooms and fruit) by these four species seems to reflect the occurrence (i.e. resource use) of their suitable hosts. On the other hand, most larval parasitoids from Tokyo attacked D. bizonata, and two larval parasitoids from Sapporo attacked D. orientacea, suggesting that the abundance of potential hosts is one of the important factors affecting their host use.  相似文献   

5.
The diversity in different groups of obligate saproxylic beetles was related to ecological variables at three levels of spatial scale in mature spruce-dominated forest. The variables were connected to: (i) decaying wood, (ii) wood-inhabiting fungi, (iii) the level of disturbance, (iv) landscape ecology, and (v) vegetational structure. Several strong relationships were found at medium (1 km2) and large scales (4 km2), while only weak relationships were found at a small scale (0.16 ha; 1 ha=104 m2). This may be explained by the local variations in habitat parameters and the high mobilities of many beetle species. Factors connected to decaying wood and wood-inhabiting fungi were clearly the most important factors at all scale levels. In particular, the variables diversity of dead tree parts, number of dead trees of large diameter and number of polypore fungi species increased the species richness of many groups and increased the abundance of many species. Eight species were absent below a certain density of decaying wood per 1 or 4 km2. Former extensive cutting was a negative factor at large scale, probably because of decreasing recolonization with increasing distance to the source habitats. Thinning reduced the diversity of species associated with birch. The development of guidelines favouring the diversity of saproxylic beetles are discussed below.  相似文献   

6.
7.
The taxonomy, reproductive biology and economic potential of Parkia (Leguminosae: Mimosoideae) in Africa and Madagascar. Three species of the pantropical woody genus Parkia are recognized from continental Africa (including São Tomé), P. biglobosa, P. bicolor and P.filicoidea. A fourth species, P. madagascariensis , is confined to Madagascar. All have capitula of similar structure although details of shape vary. Relatives sharing this capitulum structure occur in the Far East and the Neotropics. Patterns of infraspecific variation are described for the mainland species. Parkia biglobosa shows clinal variation in several leaf characters and P. clappertoniana must be regarded as synonymous. Parkia bicolor shows geographical variation especially in capitulum shape and pod width, and P. filicoidea varies geographically in its pod morphology. The red, balllike capitula are pollinated by bats; other visitors include birds, insects and non-flying mammals. In P. biglobosa a proportion of the capitula is functionally male. The pods of the African species contain mealy pulp. Dispersal involves mammals, especially primates, and birds. Information on uses, chemical composition of the seeds and insect pests is summarized.  相似文献   

8.
Species adapted to early-successional forest habitats are in managed landscapes largely confined to clearcuts. To improve habitat quality on clearcuts, green tree and dead wood retention is widely applied in forestry; however, its effects on rare early-successional species have rarely been shown. We repeatedly surveyed two red-listed beetle species (Upis ceramboides and Platysoma minus) on clearcuts in a managed boreal forest landscape. We found that U. ceramboides decreased its occupancy over time while P. minus increased, indicating that red-listed species vary in their ability to successfully utilise managed habitats. We found no effect of connectivity on probability of occurrence, colonisation or extinction per clearcut. Trees retained alive improved habitat quality of clearcuts, since both species were more frequent in dead wood of such trees, in comparison to logging residues. We suggest that retention can be improved by protecting and creating dead wood as intact trees during harvesting. Rare specialist species require habitat of high quality, and consequently it is impossible to meet the requirements of these species on every clearcut. To preserve all early-successional species at a regional scale, we recommend focusing retention of green trees and dead wood to one or a few trees species on each clearcut and in each landscape.  相似文献   

9.
Ecological restoration of abandoned, formerly forested farmland can improve the delivery of ecosystem services and benefit biodiversity conservation. Restoration programs can involve removing isolated, non‐native trees planted by farmers for fruit or wood. As such “legacy” trees can attract seed dispersers and create microclimates that help native seedlings to establish, removing them may actually slow forest recovery. Working on abandoned farmland in Kibale National Park, Uganda, we evaluated the effect of legacy trees on forest recovery by measuring the number, diversity, and biomass of native seedlings and saplings regenerating in plots centered on avocado (Persea americana), mango (Mangifera indica), and Eucalyptus legacy trees compared with adjacent plots without legacy trees. The assemblages of native, forest‐dependent tree species in plots around avocado and mango trees were distinct from each other and from those around eucalyptus and all the near‐legacy plots. In particular, avocado plots had higher stem density and species richness of forest‐dependent species than near‐avocado plots, particularly large‐seeded, shade‐tolerant, and animal‐dispersed species—key targets of many restoration plans. Furthermore, many of the species found in high numbers were among those failing to establish in ongoing large‐scale forest restoration in Kibale. Taken together, our results demonstrate that the legacy trees facilitate the dispersal and establishment of native tree species. Retaining the existing legacy trees for a number of years could usefully complement existing management strategies to restore more biodiverse native forest in degraded lands. However, careful monitoring is needed to ensure that the legacy trees do not themselves establish.  相似文献   

10.
A survey of the biodiversity of wild macrofungi, including edible species yields, was carried out from 1 May to 30 September 2007 at four different forest types (in mainly Miang tea forest). The plots 100 m2, comprised a tea garden with a few planted canopy tree species (37.2% canopy cover), a cultivated sustainable tea forest (80.2% canopy cover), an abandoned sustainable tea forest (89.8% canopy cover), and an abandoned sustainable tea forest that had suffered fire damage (72.9% canopy cover). All visible mushrooms were collected during weekly forays. Macro-characters of the fungi were annotated and photographed by digital camera and the fungi were identified to genera and morphospecies (e.g. Agaricus sp.1, Agaricus sp.2). The fresh weight of wild edible mushrooms produced in the plots was also recorded during this period. The biodiversity of macrofungi in abandoned sustainable tea forest was highest with 115 species in 47 genera, followed by cultivated sustainable tea forest with 85 species in 42 genera and fire damaged abandoned sustainable tea forest with 48 species in 25 genera, while only 19 species belonging to 15 genera were found in the tea garden. Twenty-one species belonging to nine genera with a total of 60.9 kg of edible fungi were collected throughout this study. The fresh weight of edible mushrooms was recorded with the highest fresh weight (25.3 kg) collected from the abandoned sustainable tea forest, followed by 18.2 kg in the cultivated sustainable tea forest, while in the fire damaged sustainable tea forest 16.4 kg were collected and only 1 kg was collected in the tea garden. Abandoned sustainable tea forest contained a greater shade tree biodiversity and higher canopy cover than other plots. This area has a generally higher humidity, a greater ground litter cover, a greater number of microhabitats, a greater number of trees that can form mycorrhizal associations and this probably accounts for the higher diversity of macrofungi and production of edible mushrooms. The fire damaged sustainable tea forest had lower mushroom diversity and edible mushroom production possibly due to the loss of litter and lower tree diversity. The tea garden supported a poor diversity of mushrooms and almost no edible mushrooms. Shade tea forest (Miang tea forest) is a good method to produce tea in a sustainable way as it maintains diversity of mushrooms and other organisms and could be developed as an alternative to shade coffee.  相似文献   

11.
While the number of studies on the role of biodiversity on ecosystem functioning is steadily increasing, a key component of biogeochemical cycling in forests, dead wood decay, has been largely neglected. It remains widely unknown whether and how dead wood decay is affected by diversity loss in forests. We studied the hierarchical effects of tree species diversity on wood decay rates in a subtropical forest landscape in southeast China via its influence on fungal OTU richness and invertebrate diversity using piecewise structural equation models. The experiment was conducted in natural forest plots that span a wide gradient of tree species diversity embedded in a heterogeneous topography. To account for interactions between macro‐invertebrates and fungi, that potentially modify the influence of tree biodiversity and climate on dead wood decay, we compared a macro‐invertebrate exclusion treatment with a control treatment that allowed access to all types of decomposers. Diversity effects of trees on wood decay rates were mostly negative and mediated by the diversity of macro‐invertebrates. However, the effects of tree species diversity or fungal OTU richness and macro‐invertebrate diversity on wood decay rates were comparatively weak. Temperature affected decay rates positively and had the strongest influence in all treatments. While the exclusion of macro‐invertebrates did not lead to a reduction of wood decay rates, our results suggest that they may however have a mediating role in the process. In the presence of invertebrates the predictability of wood decay rates was higher and we observed a tendency of a stronger temperature control. Our results suggest that there is evidence for diversity effects on wood decomposition, but the temperature control is still more important. Thus, an increase in mean annual temperature will increase carbon and nutrient turnover through wood decomposition in subtropical forest irrespective of biotic composition.  相似文献   

12.
Dead wood is a habitat for many insects and other small animals, some of which may be rare or endangered and in need of effective protection. In this paper, saproxylic beetle assemblages associated with different host trees in the subtropical forests in southwestern China were investigated. A total of 277 species (1 439 specimens) in 36 beetle families were collected from 117 dead wood samples, of which 101 samples were identified and respectively belonged to 12 tree genera. The number of saproxylic beetle species varied greatly among logs of different tree genera, with the highest diversity on logs of Juglans. Generally, broad‐leaved trees had a higher richness and abundance of saproxylic species than coniferous trees. Cluster analysis revealed that assemblages from broad‐leaved tree genera were generally similar (except for Betula) and assemblages from coniferous trees formed another distinct cluster. The subsequent indicator analysis proposed that there are different characteristic species for different cluster groups of host tree genera. In our study, log diameter has no positive influence on beetle species density. Conversely, comparisons of individual‐based rarefaction curves suggested that beetle species richness was highest in the small diameter class both in coniferous and broad‐leaved tree genera. With increased wood decay, proportion of habitat specialists (saproxylic beetles living on one tree genus) decreased, whereas proportion of habitat generalists (living on more than three tree genera) increased. The beetle species density was found to be higher in early stages, and decreased in later stages as well. A negative influence of altitude on saproxylic beetle species richness and abundance was detected. It was indicated that different tree genera and altitudes possibly display cross effects in modulating the altitudinal distribution and host preference of the beetles.  相似文献   

13.
Forest patches with high biological value are protected as woodland key habitats (WKH), which are identified by the presence of forest structures and indicator species. However, management for conservation needs to consider also managed forests as habitats for species. In this respect, there is a need to set quantitative targets for species and structures at different landscape scales. Due to non-intensive methods of forest management used prior to 1940 in Latvia, it might be expected that large areas of forest have developed structures that can support many species characteristic of natural forests. The aim of the study was to create a model that best described the richness of bryophyte species that are characteristic of natural forests, using forest structures as explanatory factors. The structures and bryophyte communities on living trees and coarse woody debris (CWD) were described in plots along transects blindly placed in areas dominated by State forests under commercial management. Explanatory variables related to tree species composition and tree size explained 54% of the variation in WKH indicator species richness on living trees. The best explanatory factors were maximum diameter of deciduous tree species and CWD. Low richness of total bryophyte and indicator species was found on dead wood, and the amount of variation in bryophyte species richness on CWD explained by explanatory variables was low. The study indicates the importance of deciduous tree substrate in managed forests in maintaining the spatial continuity of epiphytic species diversity. However, the forests in the managed forest landscape did not support high diversity of epixylic species, even in the WKHs, due to low diversity of suitable dead wood substrate.  相似文献   

14.
2002—2009年夏,对云南省普洱市澜沧县、景东县及其周边地区野生食用菌的物种多样性、用途或特性以及濒危等级进行了调查研究,共采集、鉴定标本593份,并对采于该区的214份馆藏标本进行了统计,野生食用菌共计35科61属134种(含变种、变型)。同时对该区市场上出售的野生贸易类群也进行了调查统计,有28科39属95种(含变种、变型)。迄今普洱共计有野生食用菌38科67属155种(含变种、变型),其中多孔菌科(Polyporaceae)所含种数最多,有17种,占总种数的10.97%;红菇科(Russulaceae)和牛肝菌科(Bo-letaceae)皆为16种,共占总种数的20.65%,灵芝菌科(Ganodermataceae)有11种,占总种数7.1%。在这些类群当中,木耳属(Auricularia)、牛肝菌属(Boletus)、乳菇属(Lactarius)、枝瑚菌属(Ramaria)、红菇属(Russula)、蚁巢菌属(Termitomyces)和革菌属(Thelephora)等属的42种真菌为普洱市场上最常见的野生贸易类群,约占云南优势野生贸易真菌总种数的52.5%。近年来,随着人们对野生食用菌消费需求的日益增长,导致其商业化采收规模急剧扩大,造成生存环境的破坏甚至丧失,从而使普洱野生食用菌,尤其是野生贸易类群的产量呈逐年下降趋势。因此,亟待采取行之有效的措施保护和管理这些珍贵的自然资源,以期达到持续利用之目的。  相似文献   

15.
Although the importance of natural habitats to pollinator diversity is widely recognized, the value of forests to pollinating insects has been largely overlooked in many parts of the world. In this review, we (i) establish the importance of forests to global pollinator diversity, (ii) explore the relationship between forest cover and pollinator diversity in mixed-use landscapes, and (iii) highlight the contributions of forest-associated pollinators to pollination in adjacent crops. The literature shows unambiguously that native forests support a large number of forest-dependent species and are thus critically important to global pollinator diversity. Many pollinator taxa require or benefit greatly from resources that are restricted to forests, such as floral resources provided by forest plants (including wind-pollinated trees), dead wood for nesting, tree resins, and various non-floral sugar sources (e.g. honeydew). Although landscape-scale studies generally support the conclusion that forests enhance pollinator diversity, findings are often complicated by spatial scale, focal taxa, landscape context, temporal context, forest type, disturbance history, and external stressors. While some forest loss can be beneficial to pollinators by enhancing habitat complementarity, too much can result in the near-elimination of forest-associated species. There is strong evidence from studies of multiple crop types that forest cover can substantially increase yields in adjacent habitats, at least within the foraging ranges of the pollinators involved. The literature also suggests that forests may have enhanced importance to pollinators in the future given their role in mitigating the negative effects of pesticides and climate change. Many questions remain about the amount and configuration of forest cover required to promote the diversity of forest-associated pollinators and their services within forests and in neighbouring habitats. However, it is clear from the current body of knowledge that any effort to preserve native woody habitats, including the protection of individual trees, will benefit pollinating insects and help maintain the critical services they provide.  相似文献   

16.
Abstract.  1. Phytophagous beetles on six mature living trees and two dead trees of Brosimum utile (Moraceae) were surveyed during 1 year in a tropical wet forest in Panama. The dead trees were surveyed both as suspended in the canopy and after falling down to the understorey.
2. Canopy access was provided by a construction crane and sampling was performed by beating and hand-collecting. The same amount of time was spent on each tree in order to standardise sampling effort. A list of all species associated with the tree is presented.
3. A total of 3009 individuals representing 364 species were collected. Tourists were excluded from the analyses by recording host associations directly and by probability assessments of host associations based on abundance categories. A total of 2603 individuals and 244 species were associated with the tree. The proportion of tourists in the trees increased with sample size.
4. A single mature living tree had on average 58.5 ± 6.5 species. The local species richness of B. utile was estimated as 2.5 times higher than in a single mature tree; however, a substantial increase in species richness was attained when dead wood habitats were included. Saproxylic species made up 82% of the total material.
5. The investigated habitat types of B. utile constituted distinct, complementary species assemblages. Similarity between saproxylic species of dead suspended wood and dead understorey wood of the same tree was 0.2 (Morisita–Horn index), confirming a prominent vertical stratification among this guild.  相似文献   

17.
The utilization of dead wood resources by woodpeckers in Britain   总被引:1,自引:1,他引:0  
KEN W. SMITH 《Ibis》2007,149(S2):183-192
Dead wood is important for woodpeckers, providing foraging, roost and nest-sites. In this paper, data from long-term studies of woodpeckers and dead wood in oakwoods in southern England are used to examine the dead wood requirements of the three British resident woodpecker species. Both Great Dendrocopos major and Lesser Spotted Woodpeckers Dendrocopos minor select dead trees for nest-sites although the former is able to nest in living trees too. On the other hand a smaller fraction of Lesser Spotted Woodpecker nests are in living trees. Green Woodpecker Picus viridis shows no selection for dead nesting trees. Hence the smallest woodpecker species appears to be most dependent on dead and decaying trees for nest-sites. Great and Lesser Spotted Woodpeckers show no preference for foraging on dead trees although they both make use of dead branches on living trees. Lesser Spotted Woodpeckers forage on smaller branches higher in the tree than Great Spotted Woodpeckers. There has been a trend for increasing dead wood resources in the study woods with both dead wood on the ground and standing dead trees (snags) increasing in the last 20 years. The levels of dead wood are shown to be the result of continual processes of creation and decay. Around 0.5% of oak Quercus spp., Ash Fraxinus excelsior and Hornbeam Carpinus betulus and 3.4% of the birch Betula spp. trees die each year in the woods resulting in a continuity of new dead snags and fallen trees. There is a high turnover of standing dead snags of oak and birch with 95% and 80% annual survival, respectively. Snags are only suitable for nesting Great Spotted Woodpeckers for a few years after their creation. It is suggested that these stand and dead wood dynamics are likely to provide habitats more favourable for the Great Spotted than the Lesser Spotted Woodpecker.  相似文献   

18.
19.
Anthropogenic habitat loss and fragmentation affect populations worldwide. For example, many bird populations of boreal forests have declined due to intensive forestry. To target conservation actions for such species, determining the key factors that affect their habitat selection is essential. Remote sensing methods provide highly potential means to measure habitat variables over large areas. We aim at identifying the key‐features of habitats by utilizing remote sensing data. As a case example, we study the nest site selection of a primary hole‐nesting passerine, the willow tit Poecile montanus, in a managed forest landscape. Using presence–absence data, we determine the most important habitat characteristics of the nest sites for three spatial scales by generalized linear mixed effect models. Our results highlight the importance of the availability of nesting sites – standing decaying deciduous trees – in the nest site selection of P. montanus. It seems to prefer moist habitats with high densities of deciduous trees and to avoid open areas, but does not require mature or intact habitats. Most of the nest site selection seems to occur within small scales. In this case, remote sensing data alone was insufficient for producing reliable models, but adding information of an ecologically important feature from direct field surveys greatly improved model performances. For the conservation and maintenance of dead wood dependent species, changes in forestry practices are necessary to keep the key characteristics of the habitat. Most importantly, continuous availability of standing decaying wood should be secured.  相似文献   

20.
We used three woodpecker species as umbrella species for old deciduous forests, and analysed their preferences in an area with old pollarded oaks in the Taurus Mountains, Turkey. Using plot inventories, we physically characterised trees utilised for nesting and foraging amongst woodpeckers in general and the Middle Spotted Woodpecker (Leiopicus medius) in particular. Trees more frequently visited by foraging woodpeckers differed from randomly chosen trees by being taller, having a larger circumference, greater bark furrow depth and shorter distance to neighbouring trees. Nesting trees were taller, had a higher proportion of dead wood but a lower surface area of natural cavities. Our results suggest that the woodpeckers in the study area rely upon woodlands containing mature trees, thus have the potential to function as suitable umbrella species’ to highlight the conservation value of oak forest habitats in southern Turkey.  相似文献   

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