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Vertical stratification of ichneumonid wasp communities： the effects of forest structure and life-history traits

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Insect Science 2015年第5期22卷 688-699页

作者： Filippo Di Giovanni Pierfilippo Cerretti Franco Mason Emma Minari Lorenzo Marini Dipartimento di Biologia e Biotecnologie 'Charles Darwin' Universita di Roma 'La Sapienza' Piazzale A. Moro 5 00185 Rome Italy Centro Nazionale per lo Studio e la Conservazione della Biodiversita forestale Corpo Forestale dello Stato via Carlo Ederle 161A 37100 Verona Italy and DAFNAE Universit& di Padova viale dell'Universita 16 35020 Legnaro Padua Italy

Parasitoid wasp communities of the canopy of temperate forests are still largely unexplored. Very little is known about the community composition ofparasitoids between canopy and understory and how much of this difference is related to forest structure or parasitoid biological strategies. In this study we investigated upon the difference in the community composition of the parasitic wasps Ichneumonidae between canopy and understory in a lowland temperate forest in northern Italy. We used general linear models to test whether parasitic strategy modifies species vertical stratification and the effect of forest structure. We also tested differences in β-diversity between canopy and understory traps and over time within single forest layers. We found that stand basal area was positively related to species richness, suggesting that the presence of mature trees can influence local wasp diversity, providing a higher number of microhabitats and hosts. The ichneumonid community of the canopy was different from that of the understory, and theβ-diversity analysis showed higher values for the canopy, due to a higher degree of species turnover between traps. In our analyses, the vertical stratification was different between groups of ichneumonids sharing different parasitic strategies. Idiobiont parasitoids of weakly or deeply concealed hosts were more diverse in the understory than in the canopy while parasitoids of spiders were equally distributed between the two layers. Even though the ichneumonid community was not particularly species-rich in the canopy of the temperate forests, the extension of sampling to that habitat significantly increased the number of species recorded.

关键词： β-diversity biological traits canopy forest structure Ichneumonidae vertical stratification

forest structure Analysis in the Oban Division of Cross River National Park, Nigeria

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Journal of Agricultural Science and Technology(B) 2012年第5期2卷 510-518页

作者： Saka O. Jimoh Peter O. Adesoye Adesoji A. Adeyemi Department of forest Resources Management University of Ibadan

Information on forest structure is important for forest management decisions. This is inadequate in many situations, especially where timber is not of primary interest. We analyzed the structure of two forest types in the Oban Division of Cross River National Park, Nigeria. Systematic sampling technique was used to establish two transects measuring 2,000 x 2 m, at 600 m interval in the two forest types in four locations. Four 50 m x 50 m plots were located alternately at 500 m intervals along each transect, constituting 32 plots per forest type and 64 plots in all, Diameters at breast height （DBH）, base; middle and top; crown diameter; total height and crown length were measured on all trees with DBH 〉_ 10 cm. There were 159 stems/ha in the close-canopy forest and 132 stems/ha in the secondary forest. The mean DBH were 34.5 cm and 33.62 cm respectively. The mean heights were 24.79 m and 23.97 m, respectively. Basal area/ha were 41.59 m2 ha~ and 27.38 m2 hal for the two forest types. Majority of the trees encountered in the two forest types belonged to the middle stratum which has implication for small mammals＇ populations. Emergent trees which are otherwise scarce in other parts of the country were recorded, which also has implications for density thinning and seed supplies.

关键词： Rainforest forest structure size systematic sampling technique distribution management.

Effects of selection cutting on the forest structure and species diversity of evergreen broad-leaved forest in northern Fujian, southern China

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forestry Studies in China 2006年第1期8卷 16-20页

作者： Qiu Ren-hui Chen Han Zhuo Li-xin Fujian Agriculture and forestry University Fuzhou 353001 E R. China General forestry Corporation of Jiangle Prefecture Jiangle Fujian 366000 P. R. China Fujian Provincial Institute of forestry Inventory and Planning Fuzhou 350000 E R. China

The short-term effects of selection curing of different intensities on the forest structure and species diversity of evergreen broad-leaved forest in northern Fujian Province were investigated and analyzed. The results showed that selection curing of low and medium intensities caused little variation in the forest structure. After curing, the dominant species retained their leading status in the community. However, the community structure changed significantly following selection curing of high and extra-high intensities; the status of the dominant species of the community declined dramatically. Some tree species began to disappear from the sampling plots. Except for extra-high intensity curing, the diversity of tree species did not change significantly for the other three curing intensities. However, the evenness of the stands was very different among the four kinds of curing plots. For low and medium intensity selection cutting, the evenness declined slightly. For extra-high intensity selection curing, the evenness increased to some extent, which might be due to a more even distribution of tree species after curing. CuRing operations resulted in some adverse reactions to development of arborous species diversity of evergreen broad-leaved forest, particularly serious damage to the forest canopy. But the rational selection cuttings, which may benefit the restoration and maintenance of species diversity over a long period and may come about from the variations in environmental factors such as sunlight, temperature and humidity.

关键词： selection cutting forest structure cutting intensities importance value species diversity

Effects of Tropical Storm on Mangroves forest structure of Dongzhai Harbor in Hainan Island

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Meteorological and Environmental Research 2010年第5期1卷 80-83页

作者：邱治军王旭杨怀张永明周光益中国林业科学研究院热带林业研究所广东龙洞510520 海南大学环境与植物保护学院海南儋州571737 农业部儋州热带农业资源与生态环境重点野外科学观测试验站海南儋州571737

The effects of tropical storm on the community structure of Sonneratia caseolaris-Sonneratia apetala(***) artificial mangroves and Ceriops tagal-Rhizophora stylosa(***) natural mangroves were analyzed in Dongzhai Harbor in Hainan Island,and the results showed that the average tree height,crown width(CW) in east-west direction(E-W) and north-south direction(N-S) of *** artificial mangroves were decreased by 2.8%,14.3% and 12.1% respectively,but the average clear bole height was increased by 60.0% after tropical *** *** natural mangroves,the average tree height and clear bole height were increased by 8.3% and 20.0%,but there was no change in CW(E-W) and CW(N-S).Therefore,tropical storm had greater effects on artificial mangroves than natural *** tropical storm,tree heights of different species increased in the following sequence:***>***>***>***,and the sequence of effect degree on CW was ***>***>***>***,while it was *** < *** < *** < *** for clear bole *** the effect of tropical storm,the average biomass loss and dry biomass loss of *** artificial mangroves were 0.22 and 0.13 t/hm2 respectively,while there was a minimal biomass loss in *** natural *** the whole,the wind resistance of natural mangroves was better than artificial mangroves,and that of *** was stronger than ***,while *** was better than ***.

关键词： Tropical storm Mangroves forest structure Effect China

Ground bryophyte species diversity in young spruce forests: effects of forest age and forest structure

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Ground bryophyte species diversity in young spruce forests: ...

Small-area estimation of forest stand structure in Jalisco, Mexico

2012年全国苔藓植物学学术研讨会

作者： Xiao-Li Yan Wei-Kai Bao Xue-Yong Pang Chengdu Institute of Biology Chinese Academy of Sciences Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization Chinese Academy of Sciences Ecological Restoration Biodiversity Conservation Key Laboratory of Sichuan Province

To evaluate important role in biological diversity in young forests, the effect of forest age on ground bryophyte diversity were studied. Furthermore, the relationship between ground bryophyte community and forest structural characteristics was verified to provide suggestion for improving ground bryophyte diversity of young forests. Three young spruce forests (PFⅠ27 years old, PFⅡ34 years old, PFⅢ 39 years old) with similar topographic characteristics were surveyed for the ground bryophyte diversity and forest structure in the upper reaches of the Dadu River, SW China. Shannon-Wiener index was not different significantly among three forests, but PFⅡ and PFⅢ had significantly higher Simpson diversity than PFⅠ. Species composition of ground bryophyte differed greatly among the three forests, which contained high proportion of rare species occurred exclusively in one of the three forests. PFⅢ contained a fewer species with pendant growth than PFⅠand PFⅡ. forest age, herb richness and herb height were important forest structural factors that influenced the distribution of bryophyte. Ground bryophyte Shannon-Wiener diversity was mainly correlated with shrub richness, while Simpson diversity was determined by the forest age. Our results suggested that in the developmental process of young forest, shrub and herb layers have an important role in determining ground bryophyte diversity. In order to improve bryophyte diversity of spruce forests, some relevant forest managements are needed to promote growth of shrub and herb layers.

关键词： ground bryophyte diversity young forests forest structure forest age

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Journal of forestry Research 2009年第4期20卷 285-292,I0004页

作者： Robin M. Reich Celedonio Aguirre-Bravo Department of forest Rangeland and Watershed Stewardship Colorado State University Fort Collins Rocky Mountain Research Station USDA Forest Service Fort Collins

Natural resource statistics are often unavailable for small ecological or economic regions and policymakers have to rely on state-level datasets to evaluate the status of their resources （i.e., forests, rangelands, grasslands, agriculture, etc.） at the regional or local level. These resources can be evaluated using small-area estimation techniques. However, it is unknown which small area technique produces the most valid and precise results. The reliability and accuracy of two methods, synthetic and regression estimators, used in smallarea analyses, were examined in this study. The two small-area analysis methods were applied to data from Jalisco＇s state-wide natural resource inventory to examine how well each technique predicted selected characteristics of forest stand structure. The regression method produced the most valid and precise estimates of forest stand characteristics at multiple geographical scales. Therefore, state and local resource managers should utilize the regression method unless appropriate auxiliary information is not available.

关键词： forest structure regression estimator synthetic estimator spatial model stratified random sampling satellite imagery inventory and monitoring

Stand dynamics of old-growth hemlock forests in central Bhutan are shaped by natural disturbances

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forest Ecosystems 2024年第4期11卷 434-447页

作者： Karma Tenzin Craig R.Nitschke Kathryn J.Allen Raphael Trouve Thiet V.Nguyen Patrick J.Baker School of Agriculture Foodand Ecosystem SciencesUniversity of Melbourne500 Yarra BlvdRichmondVictoriaAustralia School of Geography Planningand Spatial SciencesUniversity of TasmaniaSandy BayTasmaniaAustralia forest Science Institute of South Vietnam 1 Pham Van Hai StreetTan Binh DistrictHo Chi Minh CityViet Nam

Understanding how past disturbances have influenced the development of forests is critical for deciphering their current structure and composition and forecasting future *** this study,dendrochronological methods were applied to uncover the disturbance history of old-growth hemlock-dominated forests in central *** of tree-ring samples from two old-growth hemlock stands,located in two different topographic settings,identified the importance of gap-phase dynamics in facilitating recruitment and growth releases and producing complex,multi-aged structure s over *** site showed evidence of a near stand-replacing disturbance in the late 1700s,while the other showed no evide nce of high-severity disturbance at any time over the last 400 *** both sites low-to medium-severity disturbances,some of which appear to be associated with cyclones originating in the Bay of Bengal,dominated the disturbance *** hemlock stands exhibited a significant positive association between cyclone occurrence and growth release events and between recruitment pulses and growth release *** 1800 to 1970 there was an increase in recruitment of angiosperm tree species at most sites and a corresponding decline in conifer *** the past 50 years there has been little new recruitment;this may be due to light limitation in the understory from shade-tolerant angiosperms and bamboo in the lower strata of these *** variations in disturbance dynamics and recruitment were observed across the study sites,suggesting that other factors,such as topography and climate,may be influencing long-term stand development *** study highlights the complex interplay between historical disturbance regimes and tree recruitment in shaping the age and size structures of old-growth hemlock forests in central *** also provides new insights into the dynamics of these forests that can be used to support effective forest conservation and management i

关键词： forest structure Hemlock forest Himalaya Natural disturbance

Effects of Logging Intensity on structure and Composition of a Broadleaf-Korean Pine Mixed forest on Changbai Mountains,Northeast China

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Chinese Geographical Science 2016年第1期26卷 59-67页

作者： WU Zhijun SU Dongkai NIU Lijun Bernard Joseph LEWIS YU Dapao ZHOU Li ZHOU Wangming WU Shengnan DAI Limin State Key Laboratory of forest and Soil Ecology Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Liaoning Technical University Fuxin 123000China University of Chinese Academy of Sciences Beijing 100049China Jilin forest Industry Group Limited Liability Company Changchun 130021China Changbai Mountains Academy of Sciences Antu 133613China

In order to identify a harvesting model which is beneficial for broadleaf-Korean pine mixed forest （BKF） sustainability, we investigated four types of harvested stands which have been logged with intensities of 0 （T0, control）, 15% （T1, low intensity）, 35% （T2, moderate intensity）, and 100% （T3, clear-cutting）, and examined the impacts of logging intensity on composition and structure of these stands. Results showed that there were no significant differences between To and T1 for all structural characteristics, except for density of seeding and large trees. The mean diameter at breast height （DBH, 1.3 m above the ground）, stem density and basal area of large trees in T2 were significantly lower than in To, while the density of seedlings and saplings were significantly higher in T2 than in To. Structural characteristics in T3 were entirely different from To. Dominant tree species in primary BKF comprised 93%, 85%, 45% and 10% of the total basal area in T0, T1, T2 and T3, respectively. Three community similarity indices, the Jaccard＇s similarity coefficient （Cj）; the Morisita-Hom index （CMH）; and the Bray-Curtis index （CN）, were the highest for T0 and T1, followed by T0 and T2, and T0 and T3, in generally. These results suggest that effects of harvesting on forest composition and structure are related to logging intensities. Low intensity harvesting is conductive to preserving forest structure and composition, allowing it to recover in a short time period. The regime characterized by low logging intensity and short rotations appears to be a sustainable harvesting method for BKF on the Changbai Mountains.

关键词： broadleaf-Korean pine mixed forest forest structure species composition logging intensity Changbai Mountains

Does variable stand structure associated with multi-cohort forests support diversity of ground beetle (Coleoptera, Carabidae) communities in the central Nearctic boreal forest？

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Journal of forestry Research 2016年第5期27卷 1191-1202页

作者： Erica P. Barkley Jay R. Malcolm Sandy M. Smith M. Isabel Bellocq Faculty of forestry University of Toronto 33 Willcocks Street Toronto ON M5S 3B3 Canada Departamento de Ecología Genética y Evolución IEGEBA(CONICET-UBA) Facultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires Buenos Aires Argentina

Multi-cohort management （MCM） that retains a range of stand structures （age and size class） has been proposed to emulate natural disturbance and improve management in the Nearctic boreal forest. Although MCM forests contain both single- and multi-aged stands of mixed tree sizes, little is known about how variable stand structure affects associated fauna and biodiversity. Here, we examine the relationship between ground beetle （Coleoptera, Carabidae） communities and stand characteristics across a range of forest structure （=cohort classes）. Given that MCM classes are defined by the distribution of their tree-stem diameters, we ask whether parameters associated with these distributions （Weibull） could explain observed variation in carabid communities, and if so, how this compares to traditional habitat variables such as stand age, foliage complexity or volume of downed woody debris. We sampled carabids using weekly pitfall collections and compared these with structural habitat variables across a range of cohort classes （stand structure and age since disturbance） in 18 sites of upland mixed boreal forests from central Canada. Results showed that richness and diversity of carabid communities were similar among cohort classes. Weibull parameters from the diameter distribution of all stems were the strongest predictors of variation in carabid communities among sites, but vertical foliage complexity, understory thickness, and percentage of deciduous composition were also significant. The abundance of several carabid forest specialists was strongly correlated with tree canopy height, the presence of large trees, and high vertical foliage complexity. Our results demonstrate that variable forest structure, as expected under MCM, may be useful in retaining the natural range of ground beetle species across the central Nearctic boreal forest.

关键词： Biodiversity conservation Boreal forest Carabidae forest structure Ground beetles Multi-cohortmanagement Tree diameter distribution