Mapping tree aboveground biomass and carbon in Omo Forest Reserve Nigeria using Landsat 8 OLI data

Protected areas in Nigeria are important ecosystems for carbon storage. The aim of this study was to estimate and map tree aboveground biomass (TAGB) and carbon (TAGC) within a tropical forest in Nigeria. Stepwise regression analysis was implemented to develop models for predicting TAGB in the forest stand, by integrating field TAGB data with Landsat 8 OLI data. Spectral variables used in the analysis include spectral bands, vegetation indices, tasseled cap indices and principal components. Model validation was performed using independent sample plots. The results showed that incorporating more than one category of spectral variables improved the prediction of TAGB. The best-fit model was applied to map the spatial distribution of TAGB and TAGC. The TAGC was estimated as 52.3% of TAGB, based on the average carbon content of tree species derived in this study. Average TAGB and TAGC estimates for the forest stand were 373.1 ± 165.4 t ha^?1 and 194 ± 82.7 t ha^?1, respectively. Reliable estimates of TAGB and TAGC for the forest reserve were obtained. This study provides important information required to manage the forest stand for optimal carbon sequestration.     

Impacts of selective logging on above-ground forest biomass in the Monts de Cristal in Gabon

Selective logging is an important socio-economic activity in the Congo Basin but one with associated environmental costs, some of which are avoidable through the use of reduced-impact logging (RIL) practices. With increased global concerns about biodiversity losses and emissions of carbon from forest in the region, more information is needed about the effects of logging on forest structure, composition, and carbon balance. We assessed the consequences of low-intensity RIL on above-ground biomass and tree species richness in a 50 ha area in northwestern Gabon. We assessed logging impacts principally in 10 randomly located 1-ha plots in which all trees ?10 cm dbh were measured, identified to species, marked, and tagged prior to harvesting. After logging, damage to these trees was recorded as being due to felling or skidding (i.e., log yarding) and skid trails were mapped in the entire 50-ha study area. Allometric equations based on tree diameter and wood density were used to transform tree diameter into biomass.Logging was light with only 0.82 trees (8.11 m³) per hectare extracted. For each tree felled, an average of 11 trees ?10 cm dbh suffered crown, bole, or root damage. Skid trails covered 2.8% of the soil surface and skidding logs to the roadside caused damage to an average of 15.6 trees ?10 cm dbh per hectare. No effect of logging was observed on tree species richness and pre-logging above-ground forest biomass (420.4 Mg ha⁻¹) declined by only 8.1% (34.2 Mg ha⁻¹). We conclude from these data that with harvest planning, worker training in RIL techniques, and low logging intensities, substantial carbon stocks and tree species richness were retained in this selectively logged forest in Gabon.     

Applicability of semi-destructive method to derive allometric model for estimating aboveground biomass and carbon stock in the Hill zone of Bangladesh

Biomass estimation using allometric models is a nondestructive and popular method.Selection of an allometric model can influence the accuracy of biomass estimation.Bangladesh Forest Department initiated a nationwide forest inventory to assess biomass and carbon stocks in trees and forests.The relationship between carbon storage and sequestration in a forest has implications for climate change mitigation in terms of the carbon sink in Bangladesh.As part of the national forest inventory,we aimed to derive multi-species biomass models for the hill zone of Bangladesh and to determine the carbon concentration in tree components(leaves,branches,bark and stem).In total,175 trees of 14 species were sampled and a semi-destructive method was used to develop a biomass model,which included development of smaller branch(base dia 7 cm) biomass allometry and volume estimation of bigger branches and stems.The best model of leaf,branches,and bark showed lower values for adjusted R2(0.3152-0.8043) and model efficiency(0.436-0.643),hence these models were not recommended to estimate biomass.The best fit model of stem and total aboveground biomass(TAGB) showed higher model efficiency 0.948 and 0.837,respectively,and this model was recommended for estimation of tree biomass for the hill zone of Bangladesh.The best fit allometric biomass model for stem was Ln(Stem)=-10.7248+1.6094*Ln(D)+1.323*Ln(H)+1.1469*Ln(W);the best fit model for TAGB was Ln(TAGB)=-6.6937+0.809*Ln(D^2*H*W),where DBH=Diameter at Breast Height,H=Total Height,W=Wood density.The two most frequently used pan-tropical biomass models showed lower model efficiency(0.667 to 0.697) compared to our derived TAGB model.The best fit TAGB model proved applicable for accurate estimation of TAGB for the hill zone of Bangladesh.Carbon concentration varied significantly(p 0.05) by species and tree components.Higher concentration(48-49%) of carbon was recorded in the tree stem.     

The impact of community-based forest management on timber treeregeneration in north-eastern Honduras,with specific reference tobig-leaf mahogany (Swietenia macrophylla)

Reduced-impact logging is used to minimise the negative effects of selective logging. However, it has been suggested that low-impact logging may create too little disturbance for the regeneration of the light-demanding timber tree species, hence compromising forest productivity. This study evaluates the impact of low-intensity, non-mechanised, certified community forest management on timber tree regeneration. Particular attention was paid to big-leaf mahogany (Swietenia macrophylla), which has a regeneration pattern linked with large-scale disturbances. Logging gaps were compared to natural treefall gaps of an unlogged forest. There were more species of the light-demanding timber trees, but fewer individuals of the shade-tolerant timber species in the certified forest logging gaps, compared to unlogged forest treefall gaps. Furthermore, significant differences were found in the environmental characteristics of the logging and natural treefall gaps, although these only partially explained the differences in timber regeneration. Mahogany was found in over half of the logged forest gaps, whilst being nearly absent in the natural treefall gaps. However, all mahoganies in the established logging gaps were seedling-sized, indicating that regeneration may be hampered due to competing vegetation. The results of the study suggest that low-impact forest management may, at least in the short term, favour light-demanding species over the shade-tolerant ones, similarly to conventional forest management.     

A Natural Forest of Commercial Timber Species: Logging or Not Logging

Most tropical forests outside protected areas have been or will be selectively logged because the timber industry is a main income-generating resource for many developing countries. Therefore, understanding the composition of commercial timber species and logging types is key for sustainable forest management in countries like Vietnam as they move toward fulfilling Reducing Emissions from Deforestation and Forest Degradation (REDD+) agreements. Seven 1-ha plots were surveyed in the Central Highland of Vietnam, and 18 commercial tree species from these plots, whose timber is widely used by local people for housing and furniture making and timber is easily sold at local markets for high prices, were analyzed. In total, 151 tree species with a diameter at breast height (DBH) of ≥?10 cm were recorded. The 18 commercially valuable species assessed in this study accounted for 33.2% of all stems (total of 524 stems ha^?1 for all species), 47.1% of basal area (total of 34.35 m² ha^?1 for all species), and 50.8% of aboveground biomass/AGB (total of 262.68 Mg ha^?1 for all species). Practicing diameter-limit harvesting of all commercially valuable species with DBH of ≥?40 cm, which is widely performed in Vietnam, will reduce the number of stems by 7%, basal area by 31.6%, and AGB by 38.2%. Because such harvesting practices cause severe ecological impacts on the remaining forest, logged forests may require >?40 years to recover the structure status of a pre-logged forest. In addition, the recovery of the 18 commercially valuable species may require a much longer time because they comprised 33.2% of stems. Permission for logging natural forests should be given in Vietnam to sustain lives of local communities, where logging has been prohibited. However, alternative harvesting systems, such as reduced-impact logging systems, should be considered. The systems selected must simultaneously generate economic returns for local people and respect the REDD+ agreements with regard to protecting biodiversity and reducing carbon emissions.     

Earthworm population and microbial activity temporal dynamics in a Caspian Hyrcanian mixed forest

Few studies have analyzed how tree species within a mixed natural forest affect the dynamics of soil chemical properties and soil biological activity. This study examines seasonal changes in earthworm populations and microbial respiration under several forest species (Carpinus betulus, Ulmus minor, Pterocarya fraxinifolia, Alnus glutinosa, Populus caspica and Quercus castaneifolia) in a temperate mixed forest situated in northern Iran. Soil samplings were taken under six individual tree species (n = 5) in April, June, August and October (a total of 30 trees each month) to examine seasonal variability in soil chemical properties and soil biological activity. Earthworm density/biomass varied seasonally but not significantly between tree species. Maximum values were found in spring (10.04 m^?2/16.06 mg m^?2) and autumn (9.7 m^?2/16.98 mg m^?2) and minimum in the summer (0.43 m^?2/1.26 mg m^?2). Soil microbial respiration did not differ between tree species and showed similar temporal trends in all soils under different tree species. In contrast to earthworm activity, maximum microbial activity was measured in summer (0.44 mg CO₂–C g soil^?1 day^?1) and minimum in winter (0.24 mg CO₂–C g soil^?1 day^?1). This study shows that although tree species affected soil chemical properties (pH, organic C, total N content of mineral soils), earthworm density/biomass and microbial respiration are not affected by tree species but are controlled by tree activity and climate with strong seasonal dynamics in this temperate forest.     

Allometry, biomass, and chemical content of Novel African Tulip Tree (Spathodea campanulata) Forests in Puerto Rico

The African tulip tree, Spathodea campanulata, the most common tree in Puerto Rico, forms novel forest types with mixtures of native and other introduced tree species. Novel forests increase in area in response to human activity and there is no information about their biomass accumulation and nutrient cycling. We established allometric relationships and chemically analyzed plant parts of African tulip trees to determine the concentration and standing stock of chemical elements (C, N, P, K, Ca, Mg, S, Mn, Al, Fe, Na), and ash. Trees ranged in diameter at breast height from 8 to 85 cm and in height from 8.8 to 28 m. The concentrations of N, P, K, and Ca in leaves of the African tulip tree were similar to those of the native pioneer Cecropia schreberiana and higher than those of mature forest tree species in Puerto Rico. The over bark wood volume of African tulip trees in nine forest stands where it was dominant ranged from 163 to 849 m³/ha. Aboveground biomass ranged from 60 to 296 Mg/ha, and N and P stocks ranged from 190 to 988 and 32 to 137 kg/ha, respectively. Novel forests on abandoned agricultural lands can store more biomass and elements than native and plantation forest stands of similar age.     

Carbon storage in biomass,litter, and soil of different native and introduced fast-growing tree plantations in the South Caspian Sea

Replantation of degraded forest using rapidgrowth trees can play a significant role in global carbon budget by storing large quantities of carbon in live biomass,forest floor,and soil organic matter.We assessed the potential of 20-year old stands of three rapid-growth tree species,including Alnus subcordata,Populus deltoides and Taxodium distichum,for carbon(C) storage at ecosystem level.In September 2013,48 replicate plots(16 m × 16 m) in 8 stands of three plantations were established.36 trees were felled down and fresh biomass of different components was weighed in the field.Biomass equations were fitted using data based on the 36 felled trees.The biomass of understory vegetation and litter were measured by harvesting all the components.The C fraction of understory,litter,and soil were measured.The ecosystem C storage was as follows: A.subcordata(626.5 Mg ha~(-1)) [ P.deltoides(542.9Mg ha~(-1)) [ T.distichum(486.8 Mg ha~(-1))(P \ 0.001),of which78.1–87.4% was in the soil.P.deltoides plantation reached the highest tree biomass(206.6 Mg ha~(-1)),followed by A.subcordata(134.5 Mg ha~(-1)) and T.distichum(123.3 Mg ha~(-1)).The highest soil C was stored in theplantation of A.subcordata(555.5 Mg ha~(-1)).The C storage and sequestration of the plantations after 20 years were considerable(25–30 Mg ha~(-1) year~(-1)) and broadleaves species had higher potential.Native species had a higher soil C storage while the potential of introduced species for live biomass production was higher.     

Distribution patterns of tree,understorey, and detritus biomass in coniferous and broad-leaved forests of Western Himalaya,India

Forest biomass pools are the major reservoirs of atmospheric carbon in both coniferous and broad-leaved forest ecosystems and thus play an important role in regulating the regional and global carbon cycle. In this study, we measured the biomass of trees, understorey, and detritus in temperate (coniferous and broad-leaved) forests of Kashmir Himalaya. Total ecosystem dry biomass averaged 234.2 t/ha (ranging from 99.5 to 305.2 t/ha) across all the forest stands, of which 223 t/ha (91.9–283.2 t/ha) were stored in above- and below-ground biomass of trees, 1.3 t/ha (0.18–3.3 t/ha) in understorey vegetation (shrubs and herbaceous), and 9.9 t/ha (4.8–20.9 t/ha) in detritus (including standing and fallen dead trees, and forest floor litter). Among all the forests, the highest tree, understorey, and detritus biomass were observed in mid-altitude Abies pindrow and Pinus wallichiana coniferous forests, whereas the lowest were observed in high-altitude Betula utilis broad-leaved forests. Basal area has showed significant positive relationship with biomass (R² = 0.84–0.97, P < 0.001) and density (R² = 0.49–0.87). The present study will improve our understanding of distribution of biomass (trees, understorey, and detritus) in coniferous and broad-leaved forests and can be used in forest management activities to enhance C sequestration.     

Thinning after selective logging facilitates floristic composition recovery in a tropical rain forest of Central Africa

In the Congo Basin where most timber species are light-demanding, the low logging intensities commonly implemented (1-2 trees harvested ha⁻¹) do not provide sufficient canopy gaps to ensure species regeneration. The regeneration of light-demanding timber species may therefore benefit from more intensive logging, or from post-harvest treatments such as thinning by poison girdling that increases light penetration. Little is known of the impact of post-harvest treatments on the floristic composition of tropical moist forests. This study therefore aimed to assess the effects of low and high selective logging (?2.33 and 4.73 trees harvested ha⁻¹, and ?4.96 and 9.16 m² ha⁻¹ of basal area removed (logging + damage), respectively) - followed or not by thinning (?21.14 trees thinned ha⁻¹, and ?6.57 m² ha⁻¹ of basal area removed) - on the floristic composition of a tropical moist forest in the Central African Republic, from 7 to 23 years after logging.We analyzed abundance data for 110 tree genera recorded every year for 14 years in 25 one-hectare permanent subplots. We used multivariate analysis to detect floristic variations between treatments and we assessed changes in floristic composition throughout the period. We compared floristic composition recovery between thinned and unthinned subplots, using unlogged subplots as a reference characterizing the pre-logging floristic composition.Logging and thinning had little impact on the floristic composition of the subplots as quantified 7 to 23 years later, though they did increase the proportion of pioneer species. Surprisingly, additional thinning at both logging levels failed to further distance floristic composition from that of the unlogged subplots, though it did increase disturbance intensity. Floristic composition recovery appeared to be facilitated when thinning was associated with logging. Thinning seemed to favor the growth and survival of non-pioneer species, to the detriment of pioneer species. These non-pioneer species could either be non-pioneer light demanders or shade-bearers. One explanation for this is that thinning by tree-poison girdling increased light availability without causing major damage to the forest, and thus increased the growth and survival of advance regeneration. The resulting enhanced competition then reduced the survival of pioneer species.     

Effects of planting design on planted seedlings and spontaneous vegetation 16 years after establishment of forest edges

In afforestation, studies of forest edges seldom span the effects of planting design and the self-designing capacities of spontaneous vegetation. This study revisited experimental forest edge sections 16 years after their establishment to assess the impact of five design elements on (1) horizontal and vertical edge structure, (2) growth of planted species and species groups, and (3) spontaneous establishment of woody vegetation. The design elements were: exposure to direct solar radiation; edge typology (shrub mixture, mixture of trees and shrubs, no edge planting); width of edge planting (5 or 10 m); species mixture principle (intimate mixtures or single species grouping); and planting row position from outermost to interior planting row (max. 6 rows). The results demonstrate that edge plantings support significantly more spontaneous woody vegetation than stand boundaries without such edge plantings. This result was consistent across the different design elements. Position across the planting rows from the outermost to innermost row was the most influential design element for the development of planted seedlings. Planted tree and shrub species of similar shade tolerance had contradicting development, where light-demanding pioneer tree species had obtained dominant positions while shade-tolerant shrub species had outgrown more light-demanding species. These results demonstrate that important successional processes can be activated by establishing the initial components and structures of forest edges. When designing such edges, species should preferably be allocated to different row cohorts reflecting their growth form and shade tolerance.     

Woody biomass on farms and in the landscapes of Rwanda

Scattered trees and woodlots are a prominent feature of agricultural landscapes of Rwanda. However, little is known about their characteristics and their contribution to farmers’ wood needs. Here, we present the results of a survey of (a) the abundance, composition, and size of trees and woodlots in the low, medium and high altitude regions of Rwanda, (b) total woody biomass and biomass for fuelwood at farm and landscape levels, and (c) opportunities for their sustainable use. Scattered trees occurred in all landscapes at minimum densities ranging from 20 to 167 trees ha^?1. Of the 56 tree genera recorded, a handful of tree species dominated, with the ten most common species accounting for over 70 % of all trees recorded. Most of them provided fuelwood, fruit and timber to farm owners. Woodlots occurred on about 40 % of the survey farms and consisted for 90 % of eucalyptus coppice. Woody biomass dry weight of scattered trees on agricultural landscape was 0.7 t ha^?1 in low altitude region (LAR), 3 t ha^?1 in medium altitude region (MAR), and 1 t ha^?1 in high altitude region (HAR). Dry weight woody biomass in woodlots (<0.5 ha) was the highest in MAR (221 t ha^?1), followed by that in HAR (205 t ha^?1) and least in LAR (96 t ha^?1). About 80 % of total woody biomass in trees and woodlots on farmland was useable biomass for fuelwood, indicating that the production of fuelwood on agricultural land was important. Woody biomass on agricultural land was higher than that in forest plantations, and was potentially sufficient to reduce the gap between fuelwood supply and demand when the entire agricultural area was taken into account. In order to achieve this on agricultural land, while contributing to food security and environmental conservation as well, smallholder farmers must be provided with incentives to grow woodlots and to adopt agroforestry systems, thereby considering the trade-offs with agricultural production. Strategies to encourage smallholder farmers to increase the use of agroforestry have to account for the farmers’ ecological and socioeconomic conditions.     

Variation of stem density and vegetation carbon pool in subtropical forests of Northwestern Himalaya

The present study was conducted in five forest types of subtropical zone in the Northwestern Himalaya, India. Three forest stands of 0.1 ha were laid down in each forest type to study the variation in vegetation carbon pool, stem density, and ecosystem carbon density. The stem density in the present study ranged from (483 to 417 trees ha^?1) and stem biomass from (262.40 to 39.97 tha^?1). Highest carbon storage (209.95 t ha^?1) was recorded in dry Shiwalik sal forest followed by Himalayan chir forest > chir pine plantation > lower Shiwalik pine forest > northern mixed dry deciduous forest. Maximum tree above ground biomass is observed in dry Shiwalik sal forests (301.78 t ha^?1), followed by upper Himalayan chir pine forests (194 t ha^?1) and lower in Shiwalik pine forests (138.73 t ha^?1). The relationship with stem volume showed the maximum adjusted r² (0.873), followed by total density (0.55) and average DBH (0.528). The regression equation of different parameters with shrub biomass showed highest r² (0.812) and relationship between ecosystem carbon with other parameters of different forest types, where cubic function with stem volume showed highest r² value of 0.873 through cubic functions. Our results suggest that biomass and carbon stocks in these subtropical forests vary greatly with forest type and species density. This variation among forests can be used as a tool for carbon credit claims under ongoing international conventions and protocols.     

Preliminary estimation of carbon stock in a logging concession with a forest management plan in East Cameroon

ABSTRACT

Logging operations in Cameroon are based on the extraction of wood from natural forests. In this article, we assessed the carbon stock in a forest management unit (FMU) located in East Cameroon from field inventory to postfelling operations up to sawmill and export terminals. Tree basal area and aboveground biomass were calculated based on trees inventoried in the annual allowable cut. We observed that from an exploitable tree potential of 0.696 trees ha^?1 inventoried within a diameter range of 50–110 cm, 0.141 tree ha^?1 (i.e., 20% of the inventoried trees) were logged. In other words, out of 6.78 tC ha^?1 inventoried, 1.84 tC ha^?1 (i.e., 27% was logged), 1.62 tC ha^?1 arrived in the log yard and 1.3 tC ha^?1 arrived in sawmill, while 0.32 tC ha^?1 reached the export terminal. In terms of damages caused on vegetation, 4.45% of all the annual allowance cut (AAC) were affected during logging activities, this represents almost 33,188.07 tons of carbon. These findings show that the implementation of reduced-impact logging (RIL) could reduce these losses throughout the logging steps and help propose a process for the valuation of wood waste in the forest and sawmill. In this context, reducing emissions from deforestation and degradation will be engaged with the right approach.     

Individual-level analysis of damage to residual trees after single-tree selection harvesting in northern Japanese mixedwood stands

Quantifying tree damage and mortality caused by single-tree selection harvesting is critical to understanding postharvest forest dynamics and management. In this study, we quantified the effects of tree size and species and the distance from residual trees to felled trees and skid trails on damage to residual trees and mortality in mixed coniferous–broadleaved stands of Hokkaido, northern Japan. Among the 4,961 trees that we studied, 373 (7.5 %) were damaged, and 148 of these trees (3.0 %) died during or immediately after logging. Hierarchical Bayesian modeling showed that the risk of damage to residual trees increased with increasing size of the felled trees and with increasing proximity to felled trees and skid trails. Smaller residual trees had the greatest risk of damage. Species differed in their susceptibility to damage; Abies sachalinensis (Fr. Schm.) Masters and Picea jezoensis (Sieb. et Zucc.) Carr. were the most susceptible species in our sample plots. Smaller damaged trees had the highest risk of mortality. The damaged trees that did not die at the time of logging had a higher risk of postharvest mortality than undamaged trees. Our results indicate that, to minimize logging-induced damage and mortality: (1) the spatial arrangement of skid trails should be optimized and fixed, (2) the risk of skidding damage should be considered before marking the trees to be harvested and choosing the felling direction, and (3) logging operators should be instructed to avoid damaging small trees, especially those of the species that are most susceptible to damage.     

Tree microhabitats at the stand scale in montane beech–fir forests: practical information for taxa conservation in forestry

Recent studies have highlighted the key role of tree microhabitats in forest habitat complexity and have suggested using them as surrogates for local taxonomic biodiversity. However, few practical guidelines have been published to help foresters in managing microhabitats at the stand scale. This paper provides scientific background information to help to develop such guidelines. We surveyed trees in nine long-unmanaged beech–fir forests to model tree microhabitat occurrence and diversity at the tree level. Data were upscaled to a size range of tree cluster, i.e., at the tree population scale, by aggregating observed values of microhabitat occurrence. Accumulation curves were used to estimate the minimum number of trees required to make all the microhabitat types available. Two managed forests were then studied to quantify management effects on microhabitats. Diameter at breast height (dbh) and tree species, respectively, explained 16 and 10 % of the variations in the number of microhabitat-bearing trees, and 21 and 10 % for the number of microhabitat types. Beech trees and firs with a dbh of less than dbh 50 and 65 cm, respectively, did not ensure the provision of all microhabitat types. At least 20 ha of unmanaged forest were necessary to conserve all the microhabitat types. Current management practices have reduced the number of microhabitat-bearing beeches both by reducing the number of very large trees (dbh > 67.5 cm) and by tree selection within mid-size diameters. For fir, only the logging of very large trees (dbh > 62.5 cm) negatively affected microhabitats. These figures may inspire guidelines for conservation-friendly forestry.     

Forest structure and carbon dynamics of an intact lowland mixed dipterocarp forest in Brunei Darussalam

Tropical forests play a critical role in mitigating climate change because they account for large amount o terrestrial carbon storage and productivity.However,there are many uncertainties associated with the estimation o carbon dynamics.We estimated forest structure and carbon dynamics along a slope(17.3°–42.8°)and to assess the relations between forest structures,carbon dynamics,and slopes in an intact lowland mixed dipterocarp forest,in Kuala Belalong,Brunei Darussalam.Living biomass,basa area,stand density,crown properties,and tree family composition were measured for forest structure.Growth rate,litter production,and litter decomposition rates were also measured for carbon dynamics.The crown form index and the crown position index were used to assess crown properties,which we categorized into five stages,from very poor to perfect.The living biomass,basal area and stand density were 261.5–940.7 Mg ha~(-1),43.6–63.6 m~2ha~(-1)and 6,675–8400 tree ha~(-1),respectively.The average crown form and position index were 4,which means that the crown are mostly symmetrical and sufficiently exposed for photosynthesis.The mean biomass growth rate,litter production,litter decomposition rate were estimated as11.9,11.6 Mg ha~(-1)a~(-1),and 7.2 g a~(-1),respectively.Biomass growth rate was significantly correlated with living biomass,basal area,and crown form.Crown form appeared to strongly influence living biomass,basal area and biomass growth rate in terms of light acquisition.However,basal area,stand density,crown properties,and biomass growth rate did not vary by slope or tree family composition.The results indicate that carbon accumulation by tree growth in an intact lowland mixed dipterocarp forest depends on crown properties.Absence of any effect of tree family composition on carbon accumulation suggests that the main driver of biomass accumulation in old-growth forests of Borneo is not species-specific characteristics of tree species.     

Impacts of fructification on biomass production and correlated genetic effects in Norway spruce (<Emphasis Type="Italic">Picea abies</Emphasis> [L.] Karst.)

For the period 2003–2006, fructification of Norway spruce (Picea abies [L.] Karst.) was recorded at the Kranzberg forest site in Southern Germany by employing a crane with access to the canopy of more than 266 trees. For each tree, stem diameter and growth parameters were assessed annually as well as biomass of cones and seeds, number of seeds per cone, and proportions of empty seeds for a total of 371 trees with cone crop. Genotypes at 19 enzyme coding gene loci of 110 trees were included in the study of correlations between morphological and genetic traits. Re-scaling the observed values for a virtual pure Norway spruce stand of 1 ha, cone biomass including winged seeds (oven-dried at 38°C) varied between 706.8 kg/ha in 2006 (average value per tree was 3.6 kg) and values close to zero in 2005. Corresponding values for vegetative biomass increment of the coning trees in 2006 were 9,273.0 kg/ha and 10.8 kg/tree. A significant higher biomass investment was determined for dominant trees in terms of absolute cone mass as well as in terms of cone mass relative to vegetative biomass and fructification frequency. No trade-off effects in decreased vegetative biomass growth were found in the fructification year, compared to trees that did not grow cones. Although the dominant trees invested proportionally considerable biomass in cones, they showed no significant reduction in vegetative biomass growth. In the following year no decrease in vegetative growth was detected. Based on logistic regressions and homogeneity tests, respectively, significant genetic effect became evident with respect to the gene loci AAP-B and AAT-C concerning fructification probability in the year with maximum generative biomass investment. These and closely related loci also have been found to be indicative for growth and viability, respectively, in other species.     

Structure,composition and diversity of tree species in tropical moist deciduous forests of Eastern India: a case study of Nayagarh Forest Division,Odisha

Quantitative assessment of tree species diversity from sample plots in seven forest ranges of Nayagarh Forest Division in Odisha state in the Eastern Ghats of India was made during the period April, 2011 to November, 2013. A total of 120 transects(1000 m × 5 m) were laid in Nayagarh, Odogaon, Pancharida, Khandapada, Dasapalla,Mahipur, and Gania forest ranges and tree stems of at least 30 cm GBH were measured. The regeneration potential of trees was assessed from 5 m × 5 m sample plots located within the main transect. A total of 177 tree species belonging to 120 genera and 44 families were recorded from the study area. Shorea robusta, Buchanania lanzan, Lannea coromandelica, Terminalia alata and Cleistanthus collinus were the predominant tree species. The stand density varied in the range of 355.33–740.53 stems h~a)-1) while basal area ranged from 7.77 to 31.62 m~2 ha~(-1). The tree density and species richness decreased with increasing girth class. The highest number of species and maximum density was recorded in the girth class of 30–60 cm. The Shannon–Weiner and Simpson Indices with respect to trees with C30 cm GBH varied in the range of 2.07–3.79 cm and 0.03–0.37 cm respectively and the values of diversity indices are within the reported range for tropical forests of Indian sub-continent. The families, Dipterocarpaceae,Anacardiaceae, Combretaceae and Euphorbiaceae contributed to maximum species richness, stand density, and basal area. Regeneration of many tree species was observed to be poor. The present study provides baseline data for further ecological studies, forest management, and formulation of site-specific strategies for conservation of biological diversity in moist deciduous forests of Eastern India.     

Comparison of allometric equations and biomass expansion factors for six evergreen broad-leaved trees in subtropical forests in southern Korea

This study was conducted to compare the allometric equations and biomass expansion factors (BEFs) of six dominant evergreen broad-leaved trees (Camellia japonica L, Castanopsis sieboldii Hatus, Quercus acuta Thunb, Q. glauca Thunb, Machilus thunbergii S. et Z., and Neolitsea sericea Koidz) in subtropical forests. A total of 86 trees were destructively sampled to quantify the aboveground biomass of each tree component (i.e., leaves, branches, and stem). Species-specific or generalized allometric equations and species-dependent BEFs were developed for each tree component of the six broad-leaved forest trees. Species-specific allometric equations were significant (P < 0.05), with the diameter at breast height (DBH) accounting for 68–99% of the variation, whereas generalized allometric equations explained 64–96% of the variation. The values of stem density ranged broadly from 0.49 g cm^?3 for C. sieboldii to 0.79 g cm^?3 for Q. glauca, with a mean value of 0.68 g cm^?3. The BEFs were significantly (P < 0.05) lower for C. sieboldii (1.25) than for M. thunbergii (2.02). Stem density and aboveground BEFs had a significant negative relationship with tree ages. The results indicate that species-specific allometric equations and species-dependent BEFs are applicable for obtaining accurate biomass estimates of subtropical evergreen broad-leaved forests.