Showing papers on "Undergrowth published in 2011"

Demography and Dispersal Ability of a Threatened Saproxylic Beetle: A Mark-Recapture Study of the Rosalia Longicorn (Rosalia alpina)

Abstract: The Rosalia longicorn or Alpine longhorn (Coleoptera: Cerambycidae) is an endangered and strictly protected icon of European saproxylic biodiversity. Despite its popularity, lack of information on its demography and mobility may compromise adoption of suitable conservation strategies. The beetle experienced marked retreat from NW part of its range; its single population survives N of the Alps and W of the Carpathians. The population inhabits several small patches of old beech forest on hill-tops of the Ralska Upland, Czech Republic. We performed mark-recapture study of the population and assessed its distribution pattern. Our results demonstrate the high mobility of the beetle, including dispersal between hills (up to 1.6 km). The system is thus interconnected; it contained ∼2000 adult beetles in 2008. Estimated population densities were high, ranging between 42 and 84 adult beetles/hectare a year. The population survives at a former military-training ground despite long-term isolation and low cover of mature beech forest (∼1%). Its survival could be attributed to lack of forestry activities between the 1950s and 1990s, slow succession preventing canopy closure and undergrowth expansion, and probably also to the distribution of habitat patches on conspicuous hill-tops. In order to increase chances of the population for long term survival, we propose to stop clear-cuts of old beech forests, increase semi-open beech woodlands in areas currently covered by conifer plantations and active habitat management at inhabited sites and their wider environs.

Habitat selection by the highly endangered long-horned beetle Rosalia alpina in Southern Europe: a multiple spatial scale assessment

Abstract: Despite the popularity of the saproxylic cerambycid Rosalia alpina as a flagship species, its ecology is still poorly know, especially in the southern part of its range. Detailed information on its habitat preferences is needed to plan appropriate management. We set our multiple spatial scale assessment of habitat preferences in a beech forest of central Italy whose landscape, featuring both unmanaged forest and two types of grazed open forest, allowed us to look at the influence of different land uses. Preferred trees occurred in open sites, and those close to tall undergrowth were avoided. A range of moribund or dead trees were used: those preferred had a lower percentage canopy closure, significantly thicker bark, and were more sun-exposed, than the average. Logistic regression showed that the most important variables for selection were distance from nearest occupied tree, bark thickness, undergrowth height and irradiation. Occurrence likelihood augmented as the distance from nearest other occupied tree increased. Despite being mostly unmanaged, forest was avoided, whereas open forest (with trees pruned by ‘shredding’) was used more than expected. Although intensive forestry limits the availability of dead wood, closed forest may be unsuitable when shadowing useful substrate. The disappearance of traditional forms of forest management as shredding and moderate cattle grazing may lead to woody vegetation expansion and habitat closure eventually threatening the persistence of R. alpina. The return to traditional habitat management would be beneficial to R. alpina, an issue that conservation plans should carefully take it into account.

Understory plant diversity assessment of Eucalyptus plantations over three vegetation types in Yunnan, China

Abstract: Biodiversity in managed plantations has become an important issue for long-term sustainability of ecosystems. The environmental effects of plantations comprised of fast-growing introduced trees have been vigorously debated. On one hand, monocultures have been said to exhaust resources, resulting in decreased biodiversity. Conversely, it has been stated that monocultures may favor regeneration of undergrowth plants from surrounding forests, increasing biodiversity. In order to clarify the effects of planting Eucalyptus trees on species composition, diversity, and functional type of understory vegetation in Yunnan province, a field trial was implemented to compare Eucalyptus plantations (EPs) with two other local current vegetation types (secondary evergreen forests (SEs), and abandoned farmlands (AFs)). Each vegetation type was sampled in each of three elevational ranges (low = 1,000-1,400 meters above sea level (masl), medium = 1,400-1,800 masl, and high = 1,800-2,200 masl). Sample sites within each elevational range had similar environmental characteristics (slope, aspect, etc.). Thus, we sampled three vegetation types at each of three sites at each of three elevations for a total of 27 plots. We calculated relative abundance and importance value of species and diversity indexes to evaluate differences among local current vegetation types and elevational ranges, employing multivariate ordination analyses and other methods such as Analyses of Variance (ANOVA) and Indicator Species Analysis. We found that fast growing introduced Eucalyptus plantations led to reduced plant diversity in the study area, and that rare or threatened species were recorded almost exclusively in the SE plots, being essentially absent from the EP and AF plots. The understory plant diversity did not correlate with the altitude gradient significantly. Eucalyptus plantations (EPs) have a simpler community structure than that of either secondary evergreen forests (SEs; similar to natural state) or abandoned farmlands (AFs). No variable significantly explained variation of the understory shrub layer, but soil moisture-holding capacity and overstory coverage were significant in explaining variation of the understory herb layer, suggesting that the study of soil physical properties is necessary for better understanding of their importance in Eucalyptus plantations and other local current vegetation types.

Changes in stand structure due to the cessation of traditional land use in wooded meadows impoverish epiphytic lichen communities

Abstract: Wooded meadows with a history of traditional land use over thousands of years support a great diversity of various taxa. Today, however, high-species-rich communities in wooded meadows are threatened because of the cessation of traditional management in large areas. We studied lichen communities on 136 deciduous trees (Betula spp., Fraxinus excelsior and Quercus robur) in 12 wooded meadows in three regions of Estonia, and assessed the effect of habitat change due to the abandonment of traditional management on epiphytic lichen species composition, considering factors on three spatial scales: regional, habitat and individual tree. The variation partitioning approach in partial Canonical Correspondence Analysis (pCCA) revealed that most of the variation in species composition is described by the species of host tree and tree bark pH. Other tree level variables, foremost tree diameter, described as much of the compositional variation as geographic location (region) or environmental conditions in wooded meadows. Of the environmental factors studied, woodland canopy cover is the strongest predictor of the change in epiphytic lichen species composition from the community type of semi-open wooded meadows to species-poor communities characteristic of secondary forest. General Linear Model (GLM) analysis of the abundance of the 35 most frequently observed lichen species revealed that more than half of them (21) are influenced by site openness (canopy cover and/or undergrowth density), showing that increasing canopy cover has a negative effect on the abundance of epiphytic lichen species characteristic of traditionally managed semi-open wooded meadows. The results emphasize that the preservation of large old deciduous trees of various species and the maintenance of the semi-open structure of stands are vitally important for the protection of epiphytic lichen communities in wooded meadows.

Density and Height Structure of Seed- lings in Subalpine Spruce Forests of Central Europe: Logs vs. Stumps as a Favourable Substrate

Abstract: Decaying logs and stumps provide an important seedling substrate in natural subalpine forests. However, only stumps present such a role in managed forests. The aim of this study was to assess the differences in the process of seedling colonization between logs and stumps. The study was carried out in the Czech Republic, in two old-growth subalpine spruce forests located in the Bohemian Forest and Ash Mts., dominated by Athyrium distentifolium Opiz and Vaccinium myrtillus L. undergrowth, respectively. Norway spruce (Picea abies (L.) Karst.) regeneration growing on logs, stumps and non-coarse woody debris (CWD) microsites was surveyed. Regeneration (height 0–2.0 m) densities exceeded 5000 individuals per ha on both sites. The average density of P. abies regeneration per square meter of substrate was 0.3-5.719.6 and 0.5-3.8-11.0 on non-CWD microsites, logs and stumps, located in A. distentifolium and V. myrtillus undergrowth, respectively. Stumps and non-CWD microsites dominated by V. myrtillus, supported a higher proportion of taller seedlings per plot compared to the small seedlings growing on logs and non-CWD dominated by A. distentifolium ground-cover. The disproportion in regeneration densities between the stumps and the original logs decreased with increasing stages of decay. The tallest regeneration growing on stumps (root-soil plates) was significantly older than that growing on the logs (stems). Based on these two latter findings, the stumps appeared to provide suitable seedling substrates several years earlier than the logs did. Therefore, we conclude that the stumps play a more important role (relative to their covered area, 21–28 m2ha–1) in terms of suitable microsites for regeneration, than the logs do.

Pollution of “Akmenės cementas” vicinity: alkalizing microelements in soil, composition of vegetation species and projection coverage

Abstract: . The article presents the results of the research pertaining to forest litter and the composition of peat topsoil microelements, as well as the composition and projection coverage of undergrowth, herbaceous and bryophyte species specific to the vicinity of the cement factory “Akmenes cementas” are presented. Increased amounts of strontium, barium, titanium, manganese, copper, chromium, nickel and boron in forest litter and the upper 10 cm peat layer (up to 6 km from the pollution source) were established. 53 plant species were observed. The greater part (75–81%) of them are vascular plants. It was indicated that the diversity of vegetation species at different distances (0.5–1.0, 3.0–3.5 and 5.5–6.0 km) from the pollution source varies. Species of broadleaved trees and shrubs (Quercus robur L., Betula pendula Roth., Frangula alnus Mill., Corylus avellana L.), resistant to the impact of alkaline dust, are more outspread near the pollution source. Nearby the pollution source (0.5–1.0 km), Campylium...

Plant composition and growth of wild Coffea arabica: Implications for management and conservation of natural forest resources

Abstract: The montane rainforests of Ethiopia are the only places of origin and genetic diversity for Coffea arabica species. These natural forest areas with the occurrence of wild coffee gene pools are however under constant threats, largely due to anthropogenic activities. The study aims to determine the variability in plant compositions and growth of wild Coffea arabica trees in the natural forests of southeastern and Southwestern Ethiopia. The data were collected at twelve study sites. The dominant plants were broadly classified into three forest canopy strata with varying vegetation coverage among and within the study forests. The average abundance of large shade trees, wild coffee plants and shrubs was highest at Berhane-Kontir, Yayu and Bonga natural forests, respectively. The frequency of the respective plant forms was highest at Birhane-Kontir (61%), Harenna (53%) and Bonga (68%). The occurrence of the semi-domesticated spices crops was higher in the Bonga and Berhane-Kontir forests. The average plant density followed the descending order of Bonga>Yayu>Birhane-Kontir>Harenna forest, largely reflecting anthropogenic impacts. There was negative association between the growth of the coffee trees and the undergrowth shrubs. In contrast, the upper canopy large trees and coffee plants had direct relationships. However, the vegetative and reproductive growth responses of wild coffee plants were impaired, partly due to the multiple stresses in the dense forest ecology. Consequently, more than 70% of the total surface area of coffee trees did not bear crops and altogether coffee yield was low. The highest and lowest reproductive efficiencies were obtained from the Harenna and Yayu wild coffee populations, demonstrating the levels of coffee forest management practices. Overall, our findings indicated great variations in the patterns of plant co-existences and growth natures of wild coffee trees and underlines in multiple benefits of coffee forest environments, among others, as natural coffee gene pools. This depicts the need for multi-site in situ conservation and environmental management planning for sustaining biodiversity conservation and maintaining ecosystem goods and services in Ethiopia and worldwide. Key words: Biodiversity, Ethiopian wild coffee, genetic conservation, natural coffee forest, plant composition.

Regeneration of Ostrya carpinifolia Scop. forest after coppicing: modelling of changes in species diversity and composition

Abstract: In temperate forest ecosys- tems, management is one of the most relevant factors that can drive the temporal pattern of species. As species in an ecosystem show sus- ceptibility to stress and disturbance, it is use- ful to take into account the plant community "compositional dimension", which derives from species behaviour and ecological attributes and provides information on the mechanisms under- lying species assemblages. Taking into account the influence of environmental factors on species diversity and composition, in order to determine the most suitable ecological behaviour type of each species, the research aim was to generate a model for Ostrya carpinifolia coppiced woods (central Italy) that describes forest ecosystem re- generation after coppicing by the assessment of change in the composition of ecological behav- iour types. Vascular species cover percentage, field data, soil data, light intensity at the undergrowth, domi- nant tree layer cover and time since last logging were recorded for 63 plots covering 400 m 2 each (20  20 m), randomly selected within a set of homogeneous macro-environmental conditions. Low species richness is related to stressing factors (acid soil, high soil skeleton percentage), while high species richness is linked to high light inten- sity at the undergrowth level due to scarce canopy cover soon after coppicing. The driving forces af- fecting floristic composition, highlighted through multi-response permutation procedures (MRPP) were light intensity at the undergrowth, regen- erative phase, dominant tree layer cover, acidity, presence/absence of outcropping rock or rock fragments and total nitrogen content. Six species groups, each one characterized by homogeneous ecological behaviour, were defined by indicator species analysis (ISA) and tested using bioindica- tion values analysis. Floristic successional change, related to time since last coppicing, turned out to follow an ecological cycling process characterized by cyclical occurrence/disappearance of species belonging to the six groups.

Cinnamomum-Ardisia Forest in Northern Florida

Abstract: Native old-field pineland with hardwood undergrowth was replaced 42 years later by alien hardwood forest dominated by invasive species at Goodwood forest in Tallahassee, Florida. Cinnamomum camphora dominated the overstory and Ardisia crenata the undergrowth. Succession theory would have anticipated development to native southern mixed hardwood forest or a subset called magnolia-beech forest. The initial native old-field forest community, prior to alien colonization, was characterized mostly by Pinus taeda, Quercus nigra, Liquidambar styraciflua and other lowland trees that were not likely to persist indefinitely on uplands. These trees colonized abandoned fields on account of a dearth of seed sources for oak-hickory forest trees which occupied these well drained uplands in the 18th century. Oak-hickory forest had been removed in the 19th century to allow the cultivation of cotton, and there was no evidence that it would recover at Goodwood forest.

Photosynthetic response to different irradiances of undergrowth plants in tree-herb plantation: Photosynthetic response to different irradiances of undergrowth plants in tree-herb plantation

Abstract: Photosynthetic characteristics of Illicium henryi and Farfugium japonicum herbs were determined, with Cinnamomum camphora seedling as the control, under low, medium and high canopy densities of C. camphora forest in Songjiang, Shanghai. Results showed that I. henryi and F. japonicum had higher apparent quantum efficiency (AQE) and lower light compensation point (LCP). On the other hand, C. camphora seedling exhibited higher maximum photosynthetic rate (Pmax) and light saturation point (LSP). AQE of three plant species increased with increasing canopy density, and with significant differences among different canopy densities. For I. henryi and F. japonicum, Pmax initially increased and then eventually decreased, but that for C. camphora seedling decreased right throughout with increasing canopy density. While dark respiration (Rd) initially decreased and then increased for C. camphora seedling, that for undergrowth I. henryi and F. japonicum steadily decreased. There was an obvious adaptation of C. camphora seedling to low irradiance, due to decreasing LCP and LSP. But its stressed photosynthesis under high canopy density was observed. While Pmax in I. henryi and F. japonicum occurred under medium canopy density, low irradiance was accommodated by not only low LCP and LSP, but also low energy consumption. This showed that I. henryi and F. japonicum were highly tolerant to shade.

The Spatio-Temporal Variation of LAI of the Larix principis-rupprechtii Plantation Ecosystems at Diediegou of Liupan Mountains of Northwest China

Abstract: From the observation of 1eaf area index(LAI) of 7 Larix principis-rupprechtii plantation plots at 3 layers(tree canopy,shrubs and herbage) on the north slope in the vegetation period(May-Oct) of 2009,the change of LAI along slope position,the vertical composition of LAI and its seasonal variation were studied at the semi-arid watershed of Diediegou,which locates at Liupan Mountains of Northwest ChinaThe results showed: 1) The LAI of tree canopy decreased basically with rising slope position,from 152—295 at slope foot to 015—027 at slope top;the LAI of shrubs layer increased at first and then decreased with slope position,from 005—006 at slope foot to 073—101 at up-middle slope and 019—030 at slope top;while the LAI of herbage layer increased slowly,from 018—036 at slope foot to 019—075 at slope top2) The seasonal variation of LAI of tree canopy and herbage layers showed the same tendency,iea one-peak curve of increase and then decrease with timeHowever,the LAI of tree canopy layer grew faster than that of herbage layer in the early vegetation period(May-Jun) and slower than that of the herbage layer in the middle vegetation period(Jul–Aug),due to the integrated result of varying temperature and soil moisture as well as the root depth difference between trees and grasses3) With increasing tree canopy density,the LAI of each vegetation layer responded differentlyThe tree canopy LAI nearly linearly increased with canopy density;the LAI of shrubs layer increased at first and then decreased,with a maximum when the canopy density was about 05 and decreased to nearly zero when canopy density above 09;the LAI of herbage layer decreased gradually,from 074 to 035;the LAI of undergrowth(shrubs plus herbage) reached its maximum value and higher than tree canopy LAI when canopy density varied between 04—05,but decreased rapidly and lower than canopy LAI when canopy density above 06;the total LAI of all the 3 layers increased at first with rising canopy density,reaching its maximum and keeping relatively stable when canopy density was 06—08,and then slightly decreased with rising canopy density

The Annual Variation of Aboveground Biomass of Undergrowth Vegetation and Its Impact Factors in the Area of Conversion of Cropland to Forest in Duolun County

Abstract: Based on the aboveground biomass of undergrowth vegetation and climate observations in Duolun County from 2005 to 2010,the relationship of annual variation of aboveground biomass of undergrowth vegetation,vegetation cover,density,height and annual precipitation have benn analyzedThe regression model of aboveground biomass of undergrowth vegetation and its impact factor has been builtThe result shows: The aboveground biomass of conversion of cropland to forest in different years is significantly different,biomass increases significantly as the increasing of the years of conversion of cropland to forestThe aboveground biomass of undergrowth vegetation in the area of conversion of cropland to forest has strong correlation with the years of conversion of cropland to forest,vegetation density and heightThe biomass increases as the increasing of the years of conversion of cropland to forest,vegetation density and heightThe aboveground biomass in the area of conversion of cropland to forest can be predicted by the linear relationship of variation of vegetation height

Research on the Biomass of Pinus massoniana Plantations

Abstract: The spatial distribution patterns of biomass of 5-years Pinus massoniana plantation were investigated in Jiangle County.The result indicated that the total biomass of P.massoniana was 35.512 t/hm2,the biomass of tree layer,undergrowth vegetation layer and litter layer were 28.608 t/hm2,3.861 t/hm2,3.043 t/hm2,respectively,which accounted for 80.56%,10.87%,8.57%,respectively.The biomass distribution of each organ in tree layer followed the order of stems(40.90%)branches(25.73%)roots(23.87%) leaves(9.50%).In terms of the biomass distribution patterns above ground in tree layer,the biomass distribution of branches and leaves of P.massoniana were mainly in 1-3 m section,whereas,the biomass distribution of stem were mainly in 0-2 m section.

IMPLICATION FOR IN SITU CONSERVATION OF INDIGENOUS SPECIES WITH SPECIAL REFERENCE TO WILD Coffea arabica L. POPULATION IN MOUNT MARSABIT FOREST, KENYA

Abstract: Mt. Marsabit forest is the only forest in Kenya where Coffea arabica L. (Rubiaceae) occurs naturally in wild populations. This forest however is highly fragmented and decreasing at a rapid rate due to anthropogenic activities. This study assesses the diversity and structure of species of conservation concern with reference to wild coffee as basis for management, conservation and use of wild genetic resources in Kenya. A botanical inventory and diversity study identified 52 species of trees and shrubs, 12 species of herbs and six species of climbers and lianas were recorded and belonged to 35 families and 64 genera. Rubiaceae (Coffee family) was the richest family with nine species followed by Euphorbiaceae with six species. Rinorea convallarioides (Bak.f.) Eyles ssp. marsabitensis Grey-Wilson (Violaceae), an endemic species, and Drypetes gerrardii Hutch. (Euphorbiaceae), were the two most important species, accounting for more than third of the combined importance value. Coffea arabica was dominant in the forest undergrowth with a higher density occurring in the open patches where it was competing with other shrubs and small trees in the undergrowth. T he success and future management and conservation strategy of this forest depend on how to conserve the forest genetic resources especially of this wild species.

Status of Plant Biodiversity in Mt. Malarayat, Batangas, Philippines

Abstract: The study determined the vegetative structure and assessed the current status of plant biodiversity in Mt. Malepunyo, one of its peaks. Herbarium of its floristic composition served as the baseline for future monitoring and scientific undertakings in the area. The quadrat technique was used to determine the vegetative structure and ecological dynamics of the forest of Mt. Malarayat- Malepunyo. The size of the quadrat was 100 square meters each (10x10 m). A total of 20 quadrats used were situated more or less along the trail to the peak. The study recorded a total of 104 species under 60 families; of which 46 species are indigenous or native to the Philippines; 27 species are introduced; 23 species endemic to Mt. Malarayat; and 9 species were unclassified. Eleven (11) were threatened species included in the conservation priority areas. The flora is composed of 67% trees, mostly from families Moraceae, Euphorbiaceae, Lauraceae, Meliaceae and Rubiaceae. The undergrowth layer includes shrubs (13%), vines (11%) herbs (5%) and ferns (4%). Its potential threats and anthropogenic disturbances include presence of invasive species, impacts of unregulated tourism activities, small scale timber poaching, hunting and land conversion. Keywords - status, plant biodiversity, Mt. Malarayat, species richness

Photosynthetic response to different irradiances of undergrowth plants in tree-herb plantation

Abstract: Photosynthetic characteristics of Illicium henryi and Farfugium japonicum herbs were determined,with Cinnamomum camphora seedling as the control,under low,medium and high canopy densities of C.camphora forest in Songjiang,Shanghai.Results showed that I.henryi and F.japonicum had higher apparent quantum efficiency(AQE) and lower light com-pensation point(LCP).On the other hand,C.camphora seedling exhibited higher maximum photosynthetic rate(Pmax) and light saturation point(LSP).AQE of three plant species increased with increasing canopy density,and with significant differences among different canopy densities.For I.henryi and F.japonicum,Pmax initially increased and then eventually decreased,but that for C.camphora seedling decreased right throughout with increasing canopy density.While dark respiration(Rd) initially decreased and then increased for C.camphora seedling,that for undergrowth I.henryi and F.japonicum steadily decreased.There was an obvious adaptation of C.camphora seedling to low irradiance,due to decreasing LCP and LSP.But its stressed photosyn-thesis under high canopy density was observed.While Pmax in I.henryi and F.japonicum occurred under medium canopy density,low irradiance was accommodated by not only low LCP and LSP,but also low energy consumption.This showed that I.henryi and F.japonicum were highly tolerant to shade.

Study on carbon storage and distribution patterns of Pinus elliottii stand in rocky desertification area in Shaoyang county,Hunan province

Abstract: Carbon content and carbon storage and distribution pattern in different rocky desertification degree(mild,moderate,and severe) Pinus elliottii artificially young forests in Shaoyang county were investigated in field sample plot with the method of indoor potessium dichromate potassium-hydration heat.And the results show that: in the rocky desertification control engineering,the spatial distribution of carbon stock of Pinus elliottii plantation ecology system were: soil layerthe tree layerthe undergrowth layerlitter layer.Carbon stock total range was 20.018~41.284 t/hm2,and the average value was 29.563t/hm2.With the increasing of rocky desertification degree and the decreasing of stand density,carbon ossus point also reduced,and the differences were significant.Soil carbon ossus point were 26.109t/hm2,19.165t/hm2,14.282t/hm2 respectively.The tree layer carbon ossus point were 4.817t/hm2,13.800t/hm2,2.319t/hm2,respectively.And more serious the rocky desertification was,the carbon stock was more smaller.The order of each component carbon storage in mild and moderate was trunktree leavesrootbranch,in severe was tree leavestrunkrootsbranches.while,the carbon stock of undergrowth and litter layer were the smallest in the mild rocky desertification,their average values 2.030t/hm2,0.703t/hm2 respectively.

Niche Characteristics of Undergrowth Herbaceous in Typical Reforest Cultivated Land Area in North Shaanxi Province

Abstract: Based on a field plot sampling method to investigate community niche of undergrowth vegetation in typical lands use conversion from agricultural lands into forest lands.Species diversity indices,parameters of niche breadth,niche similarity and niche overlap were calculated to analyze niche characteristics in 16 different models and periods of land use conversion from agricultural lands into forest lands communities in Ansai country.The results showed that the species diversity indices in land use conversion from agricultural lands into forest are better than land use conversion from agricultural lands into shrubbery.Niche breadth of Lespedeza davurica and Heteropappus altaicus were larger than that of other species.With Shannon-Wiener(Bs-w,i) and Levins(Bl,i) values being 0.89,0.83 and 0.64,0.58.Niche overlap degree between species increased with niche breadth,which was shown in H.altaicus,Artemisia gmelinii,Stipa bungeana,etc.There was no obvious correlation between niche similarity and niche breadths.174 sets of species had niche similarity values greater than 0.5,accounting for 91.6%.Therefore,species had different requirements to environment,and species could harmonious exist in communities.

Carbon Storage and Its Distribution of Eucalyptus urophylla×E.tereticornis Plantations in Hainan Island,Southern China

Abstract: Based on the investigated data of 54 plots of 18 sites in the west coastal area,north plain area,east coastal area and central mountainous area of Hainan Island,the biomass,carbon storage,carbon sequestration and spatial distribution of eucalyptus plantations in Hainan Island,southern China were analyzed.The results indicated that the mean total biomass was 49.72 t·hm-2,and the biomass distribution of the forest system showed such a sequence as:arbor layer(85.10%)litters(8.08%)undergrowth layer(6.82%).The mean total organic carbon storage in the eucalyptus plantation ecosystem amounted to 88.84 t·hm-2,of which there was 23.13%(20.55 t·hm-2) stored in the arbor,1.74%(1.55 t·hm-2) in undergrowth vegetations,2.17%(1.93 t·hm-2) in litters,and 72.96%(64.81 t·hm-2) in the soil(0-100 cm).The stem had the biggest organic carbon storage of the total carbon storage in various plant organs,accounted for 52.81% of carbon storage in arbor layer.The mean annual net productivity of eucalyptus plantations was 17.56 t·hm-2a-1,with a mean annual stored carbon up to 8.43 t·hm-2,amounted to 30.91 t CO2·hm-2a-1.The total organic carbon storage and sequestration of the eucalyptus plantations of Hainan Island was 2 958.37×104 t and 280.97×104 t·a-1,respectively.The carbon sequestration of eucalyptus plantations in the central mountain area(11.89 t·hm-2a-1) was largely higher than other three areas,such as the northern plain area(8.97 t·hm-2a-1),the western coastal area(7.18 t·hm-2a-1) and the eastern coastal area(8.26 t·hm-2a-1).The three areas had no significant difference in the carbon sequestration.Except for the western coastal area and the eastern coastal area,the carbon storage among all other areas was significantly different,mainly because of their different carbon storage of soil.

Altitudinal Variation in Aboveground Biomass of Abies georgei var. smithii at Timberline of the Sergyemla Mountains,Southeast Tibet

Abstract: Environment becomes harsh with increasing altitude,which has major effects on forest biomass accumulation and its allocation to woody and foliage components.In this study,we compared aboveground biomass and its allocation pattern of Abies georgei[ var.smithii along a transect from sub-alpine forest to alpine timberline in the Sergyemla Mountain,southeast Tibet.We estimated different components of aboveground biomass for Abies trees and undergrowth Rhododendron shrubs by using allometric regressions.The aboveground biomass of undergrowth herbs was measured by harvesting in 0.5 m×0.5 m quadrats.Aboveground biomasses were 181~284 t/hm2,117~248 t/hm2,35~62 t/hm2 and 0.9~1.5 t/hm2 for whole community,trees,undergrowth shrubs and herbs,respectively.Aboveground biomass of the whole community decreased significantly with increasing elevation,and the decreasing rate was 73.1 t/hm2 per 100 m.Furthermore,the Abies forest stand at higher elevation tended to reduce biomass allocation to non-photosynthesis organs(stem and branch),and to increase the allocation to long-lived needles.The increased biomass allocation to long-lived needles at higher elevations may extend the mean residence time of nutrients in plants,and then enhance nutrient use efficiency of dry mass production to adapt to the low temperature environment at alpine timberlines.

Research on Biomass and Undergrowth Soil Nutrient of Main Tree Species for Shelterbelt along Fujian Coastal Area

Abstract: Shelterbelt plays an important role in improving the environmentThe research on biomass,litter fall and forest soil nutrient could deepen the understanding of the tree growth laws and the interrelationship between the tree and the environmentThe average sample tree method was adopted to determine the biomass of main tree species for shelterbelt in Haitan Island,namely Casuarina equisetifolia L,Acacia confusa Merr,Pinus thunbergii Parlatore and Pinus elliottii EngelmannThe growth habit and the abundance and deficiency of nutrients among the four species were analyzed through the litter collecting and soil nutrient measurementThe results indicated that: ① The order of the total biomass from large to small was Pinus elliotii Engelmann(27084 t/hm2)Pinus thunbergii Parlatore(12572 t/hm2)Acacia confusa Merr(7599 t/hm2) Casuarina equisetifolia L with bad slash regeneration(5602 t/hm2)② From the study of litter,it could be concluded that September was the common growth month and the litter production was large,but for Casuarina equisetifolia L and Acacia confusa Merr,another peak of litter return was in May③ According to the soil nutrient of the four species,the undergrowth soil nutrient of Acacia confusa Merr was relatively abundant,but nutrient substances of the four tree species were comparatively poor on the wholeThis might influence the biomass of shelterbelt and then affect the function of the windbreak and sand fixation and also the soil and water conservation

Zmiany struktury drzewostanów sosnowych a wystêpowanie ptaków

Abstract: Changes of Pine stand structure versus birds' occurrence. Forest structure can be defined as occurrence of some key elements important for its functioning such as, for example, layering, presence of dead trees, sizes of tre- es, species richness of the forest stand, diversity of the undergrowth and ground cover. The structure understood in such a way is dynamic and changes with the age of a forest stand and reaches its height far after the age of cutting. Changes in the structure seem to be the key element responsible for occurrence of specia- lized bird species. In respect of structure development one can divide Pine stands into four groups: young (10-80 years old), maturing (81-120 years old), mature (121-160 years old) and aging (above 161 years old). Promotion of a complex structure characteristic for old forests can be the basis for actions of forest prac- tice for birds' protection.

Volymsrapportering vid terrängtransport av virke

Abstract: This report is a B.Sc. Forestry thesis work at the school for Forest Management, SLU. The work was an assignment from the forest owners’ association Mellanskog. The aim of the work where to investigate the economical result of removing undergrowth trees before first thinning, and a follow-up of the contractors and their compliance with Mellanskog standards. This thesis work was divided in three parts: The first was to find a relation between the net volume from the first thinning and the cost of cleaning undergrowth trees. Secondly there was a follow-up in the field, to investigate whether the contractors have done the undergrowth cleaning according to Mellanskog’s directives. The last part of the assignment was an inquiry examination to both thinning machine contractors and cleaning contractors, including interviews with some of them. One hypothesis, which we shared with our assigner (Mellanskog), was that all contractors didn`t follow the directives. According to the directive all obstructive undergrowth up to 8 cm diameter in breast height (1,3 meters above the ground) should be removed. Trees with a breast height diameter <8 are common in first thinning stands after cleaning, which is unprofitable for all links of the forest supply chain. Results from the field investigation, shows that 17 % of all remaining trees after cleaning are less than 8 cm breast height diameter. The history of forest management plays a crucial role for the result of undergrowth cleaning. If cleaning has been made once or twice earlier in the stand, the contractor`s job is easier since selection of main stems is already done. Otherwise the contractors made a god job according Mellanskog’s directive. The investigations show that there is a connection between average stem volume (solid under bark) and the cost of cleaning. If the average stem is small the cost will be high and vice versa. Result from the inquiry shows that the contractors understand well how the undergrowth cleaning should be done in theory, in practice, result shows that the contractors does not comply with the directive, i.e. to remove all obstructive undergrowth up to 8 cm diameter in breast height (according to the machine contractors). One positive observation is that the machine contractors have also experienced an obvious improvement of the undergrowth cleaning in the last years.

Phytocénose à Mallotus oppositifolius et Macrosphyra longistyla dans le sous—bois des plantations privées de teck (Tectona grandis) de la commune d'Abomey-Calavi, Sud-Bénin

Abstract: A study has been undertaken in the natural undergrowth of private teak plantations in Abomey—Calavi using the synusial approach to phytosociology. Pedological and topographical factors and private teak plantation production within plant communities have been studied. Mallotus oppositifolius and Macrosphyra longistyla community is identified on acid clayey—sandy soils. It is composed of eight vegetal synusia and represents the fourth stage growth of the vegetation succession in the study area. Mean diameter of teak in this plant community varied between 5.7 cm and 15.8 cm while the mean height is between 6.5 m and 13 m and, the basal area between 10.7 m2/ha and 18.9 m2/ha. This community is indicative of the most productive forest sites of the municipality.

Структура и динамика высокогорных лесов Северо-Чуйского хребта (горный Алтай) в условиях изменений климата

Abstract: The age structure of high altitudinal forests and fluctuations of tree radial increment were studied on sample areas in the waterhead of the Aktru river on the northern macroslope in the central section of Severo-Chuisky Range (the Altai Mountains) at 2150-2350 m a.s.l. The study area falls into the Central Altai mountain hollow province of larch and dark coniferous forests. The main tasks were to study the age structure of the forests, to isolate generations, and to built and analyse tree ring width chronologies. At the upper forest line in the Aktru river valley the relatively closed stands are Siberian stone pine open woodlands located at 2350 m a.s.l. The pure old Siberian stone pine forests grow lower the line. The Siberian larch and Siberian stone pine forests locate down to 2200 m a.s.l. The altitude decrease as low as 2150-2100 m a.s.l., the younger Siberian larch and Siberian stone pine forests of the after-fire origin supersede the primary old forests. Within these altitudes the pure mid-aged Siberian larch forests grow. The undergrowth is mainly the Siberian stone pine. The Siberian stone pine (515 years) and the Siberian larch (525 years) tree ring width chronologies were built in order to assess the climate effect on the radial growth. The coefficients of correlation between the individual ring rows of different sites are 0.35-0.72. The synchronism is 0.69. According to the ring chronologies, there are similar trends of increasing and decreasing growth in Siberian stone pine and larch trees. The radial growth correlates positively with the spring and summer month temperatures (coefficients of correlation is 0.55 in May and 0.50 in June and July). The analysis of the age structure of the forests and fluctuation of the radial growth demonstrates that the increasing increment corresponds with the appearance of groups of the trees of close ages in all the sites of the valley. The young Siberian stone pine generation can be produced under canopy and in stand gaps from the undergrowth at the upper forest line and in the forests near it. Now there is intensive Siberian stone pine regeneration in both the primary and after-fire Siberian stone pine forests and Siberian larch forests with Siberian stone pine trees. The close periods of producing the generations at and near the forest line indicate the significance of the climate change in the growth, development and distribution of these forests in Severo-Chuisky Range. Relief is also important for forest development because it is a natural barrier for strong fires and has therefore an influence on conservation of the primary old Siberian stone pine forests with several generations.