Litter Carbon Stocks Research Articles

Contribution of legume tree residues and macrofauna to the improvement of abiotic soil properties in the eastern Amazon

The potential advantages of positive interactions between the functional group components of the soil macrofauna and soil residue cover may increase the sustainability and efficiency of tropical agrosystems. The objective of this study was to link the ecological requirements of soil macrofauna with their impacts on the principal chemical and physical indicators of a hardsetting soil from a humid tropical region. The soil of a no-tillage system covered with legumes tree residues was subjected to the following treatments: Leucaena+Clitoria (L+C); Leucaena+Gliricidia (L+G); Leucaena+Acacia (L+A); Gliricidia+Clitoria (G+C); Gliricidia+Acacia (G+A); and a control with bare soil (BS) and no legumes. The application of leguminous tree residue with a high C/N ratio (G+A) extended essential ecosystem functions in the no-tillage agrosystem due to the favoring abundant functional groups, including soil engineers, predators and litter transformers. Litter transformers are associated with mulching effects that enhance multiple attributes, such as water infiltration, soil porosity, soil density, the litter carbon stock, the free light fraction (FLF) and total organic C. The use of fast-growing leguminous trees can increase soil acidity and decrease soil macrofauna diversity, but the harmful effects of leguminous tree cover are minor relative to the environmental benefits.

A Comparative study of Carbon Stocks in Shorea Robusta and Schima-Castanopsis Forests in Siwalik and Lesser Himalayan Zone Nepal

A study was conducted to estimate the of above ground and below ground carbon stocks in trees, shrubs, herbs/grasses and leaf litter in Kankali community forest of Chainpur Village Development Committee (VDC), Chitwan district and Tibrekot community forest of Hemja Village Development Committee (VDC), Kaski district of Nepal. The tree volume was calculated by using allometric equation with the help of height and diameter (non-destructive method). Herbs/grasses, shrubs and leaf litters biomass were estimated in laboratory by oven dry method and some conversion and unitary methods. Carbon stocks of vegetation as well as other category were estimated by considering default value as 0.43 of the total biomass. The total forest biomass was estimated 147.01 t/ha and 98.28 t/ha in Shorea robusta and Schima- Castanopsis dominated forests respectively. S. robusta dominated forest has occupied the carbon stocks of 63.22 t/ha, and out of this above ground carbon stock was 48.93 t/ha (77%) and below ground carbon stock was 14.29 t/ha (23%) followed by Schima-Castanopsis dominated forest having total carbon stock 42.26 t/ha, which contain in above ground 30.60 t/ha (72%) and in below ground 11.66 t/ha (28%). The total carbon content in S. robusta dominated forest including all categories was 20 % higher as compared to the Schima-Castanopsis forest. Kankali community forest was having higher tree density, dbh and height of trees as compared to Tibrekot community forest.

Forest Carbon Stocks in Woody Plants of Mount Zequalla Monastery and It’s Variation along Altitudinal Gradient: Implication of Managing Forests for Climate Change Mitigation

Carbon sequestration through forestry has the potential to play a significant role in ameliorating global environmental problems such as atmospheric accumulation of GHG's and climate change.The present study was undertaken to estimate forest carbon stock along altitudinal gradient in Mount Zequalla Monastery forest. Systematic sampling methods were used to collect data from seventy 10 m x 20 m rectangular plots. The area was dominated by Juniperusprocera tree species. The mean carbon stock per hectare was 237.2, 47.6, 6.5 and 57.6 ton for above ground biomass, below ground biomass, litter biomass and soil respectively. The mean total carbon stock in Mount Zequalla Forest was 348.8 t ha-1. The statistical analysis for carbon stock variation in the different carbon pools through altitudinal gradient showed a significant variation with exception for soil organic carbon stock. The amount of carbon stock in above and below ground biomass showed increasing pattern with increasing altitude whereas litter and soil organic carbon stocks showed decreasing pattern with increasing altitude.Overall this study points out Mount ZequallaMonastery forest has the potential to sequester plenty of CO2 with a considerable variation along altitude. Thus, it has paramount importance to give conservation priority to the forests to achieve climate change mitigation aspiration especially through forest carbon sequestration mechanism. Keywords : Carbon sequestration; Climate change; Altitudinal gradients; Mount Zequalla Monastery; Forest

Forest Carbon Stocks in Woody Plants of Arba Minch Ground Water Forest and its Variations along Environmental Gradients

The role of forests in mitigating the effect of climate change depends on the carbon sequestration potential and management. This study was conducted to estimate the carbon stock and its variation along environmental gradients in Arba Minch Ground Water Forest. The data was collected from the field by measuring plants with a DBH of >5cm in quadrat plots of 10 X 20 m and the carbon stocks of each plant were analyzed by using allometric equations. From this study the mean total carbon stock density of Arba Minch Ground Water Forest was found to be 583.27 t ha-1, of which 829.12 t ha-1, 165.88 t ha-1, 1.28 t ha-1, 83.80 t ha-1 was contained in the above ground carbon, belowground carbon, litter carbon and soil organic carbon (0-30 cm depth) 0respectively. Similarly, the analysis of carbon stock variation of different carbon pools on eight different aspects of the forest area showed a significant variation with the exception of litter carbon stock and this is due to fast decomposition rate of litters and low amount of litter fall in the forest. The amount of carbon stock in above and belowground biomass, soil organic carbon and the total carbon stock was higher on the southern aspect as compared to other aspects. This study concluded that the carbon stock value of Arba Minch Ground Water Forest is large, and this will serve as a potential entry point for the engagement of the forest in REDD project. Keywords : Environmental variables; Ground Water Forest; Climate change; Biomass; Forest carbon stock

Caracterização e estoques de carbono de sistemas agroflorestaisno Cerrado de Minas Gerais

Os sistemas agroflorestais (SAFs) além de geração de renda e conservação da biodiversidade pode ser uma alternativa para a estocagem de carbono. O trabalho teve como objetivo caracterizar três sistemas agroflorestais (SAFs) e estimar os estoques de carbono na fitomassa aérea, na serapilheira e no solo. Os SAFs e suas respectivas vegetações nativas adjacentes foram caracterizados quanto ao número, classificação botânica,distribuição diamétrica e estratificação vertical dos indivíduos arbóreose. Em cada um dos sistemas, foram estimados os estoques de carbono na fitomassa aérea, na serapilheira e no solo. Os SAFs,implantados a partir do manejo da vegetação nativa, apresentaram uma biodiversidade vegetal e estoque de carbono na fitomassa, na serapilheira e no solo semelhantes à área de vegetação nativa adjacente. Por outro lado, os estoques de carbono no SAF implantado em área anteriormente cultivada com culturas anuais apresentou menor diversidade de espécies arbóreas e estoques de carbono na fitomassa, serapilheira e no solo, em relação à vegetação nativa adjacente. Sistemas agroflorestais bem manejados se assemelham à vegetação nativa em estoque de carbono e conservação da biodiversidade dos recursos naturais.

Sustainability of forest bioenergy in Europe: land‐use‐related carbon dioxide emissions of forest harvest residues

AbstractIncreasing bioenergy production from forest harvest residues decreases litter input to the soil and can thus reduce the carbon stock and sink of forests. This effect may negate greenhouse gas savings obtained by using bioenergy. We used a spatially explicit modelling framework to assess the reduction in the forest litter and soil carbon stocks across Europe, assuming that a sustainable potential of bioenergy from forest harvest residues is taken into use. The forest harvest residue removal reduced the carbon stocks of litter and soil on average by 3% over the period from 2016 to 2100. The reduction was small compared to the size of the carbon stocks but significant in comparison to the amount of energy produced from the residues. As a result of these land‐use‐related emissions, bioenergy production from forest harvest residues would need to be continued for 60–80 years to achieve a 60% carbon dioxide (CO2) emission reduction in heat and power generation compared to the fossil fuels it replaces in most European countries. The emission reductions achieved and their timings varied among countries because of differences in the litter and soil carbon loss. Our results show that extending the current sustainability requirements for bioliquids and biofuels to solid bioenergy does not guarantee efficient reductions in greenhouse gas emissions in the short‐term. In the longer‐term, bioenergy from forest harvest residues may pave the way to low‐emission energy systems.

Forest Carbon Stocks and Variations along Altitudinal Gradients in Egdu Forest: Implications of Managing Forests for Climate Change Mitigation

The role of forests in mitigating the effect of climate change depends on the carbon sequestration potential and management. Although a number of studies have been done on carbon stock estimations, the influence of environmental factors on forest carbon stocks has not been properly addressed. This study was conducted to estimate the carbon stock and itsvariation along the altitudinal gradients in Egdu dry afromontane forest. The carbon stock in the different carbon pools and analysis of the influence of the environmental variables were studied by collecting data in quadrat plots of 10 X 20 m distributed along transect lines. The mean totalcarbon stock density of Egdu forest was found to be 614.72±35.79 t ha-1 (ranging from 182.6 to 1416 t ha-1), of which 278.08±25.72 (19 to 782.28 t ha-1) was contained in the above ground biomass, 55.62 t ha-1 (8.06 to 332.89 t ha-1) in below ground biomass, 3.47±0.2 (0.33 to 7.53 t ha-1) in litter carbon and 277.56±11.56 t ha-1 (148.74 to 551.30 t ha-1) was stored in soil organic carbon (0-30 cm depth). The carbon stocks in above ground biomass, below ground biomass, litter biomass and soil organic carbon exhibited distinct patterns along altitudinal gradients. The above ground, below ground and soil organic carbon stock showed an increasing trend with increasing altitude while the litter carbon stock showed irregular patterns along altitude though statistically there was no strong relationship between each of these carbon pools and altitudinal gradients. This study concluded that the carbon stock value of Egdu forest is large, and thecarbon storage in different carbon pools of the forest area varies with altitudinal gradient.

森林の枯死木・リター・土壌の炭素蓄積量の地域分布とその決定要因

森林の枯死木・リター・土壌の炭素蓄積量の地域分布とその決定要因

Carbon and biomass stocks in a fragment of cerradão in Minas Gerais state, Brazil

This study aimed at quantifying carbon (C) and biomass stocks in shoot portion, leaf litter, roots and soil within a fragment of dense savanna 'cerradão', 158.5 ha in area, located in Minas Gerais state. Measures were quantified using dendrometric parameters obtained during the forest inventory and collection of leaf litter, root and soil samples. Furrows were dug in the soil each 100 cm long, 50 cm wide and 100 cm deep in order to collect root samples at depths of 0-30 cm, 30-50 cm and 50-100 cm, and soil samples from the layers 0-10 cm, 10-20 cm, 20-40 cm, 40-60 cm and 60-100 cm, as well as any leaf litter from the surrounding surface. Analyses were performed in the Organic Matter Study Laboratory (DCS/UFLA) to determine C contents in the above matrices, using an Elementar analyzer model Vario TOC Cube. Higher C contents and stocks and lower density were noted in topmost soil layers. In cerradão, shoot portion was found to be the matrix contributing the most to biomass production, followed by roots and leaf litter. Carbon stock in the fragment was 139.7 Mg ha-1. Soil was the matrix contributing the most to stocked C (64.8%), followed by the shoot portion (26.3%), roots (5.2%) and leaf litter (3.7%).

The effects of thinning on carbon stocks and fluxes in a Chinese arborvitae plantation

China has extensive areas of forest plantations that sequester and store large quantities of carbon. However, the rate of carbon sequestration by Chinese arborvitae (Platycladus orientalis Linn. Franco) is unknown. This research looks at carbon stocks and fluxes in forest vegetation, soil and litter seven years after thinning Chinese arborvitae in order to evaluate the effect of thinning levels on carbon sequestration. At 22 years, the plots were reduced from 5900 to 4100 and 3000 trees per hectare in three replicates. Carbon stocks of above-ground tree materials were lowest in the heaviest thinned plots and highest in the control plots. Above-ground shrub carbon pools were the opposite, i.e., largest in the heaviest thinned plots and lowest in the controls. Soil and litter carbon stocks were not affected by thinning treatment. Results suggest that thinning may positively affect vegetation carbon sequestration in the short term, an important observation for forest managers using thinning to optimize carbon sequestration capacity.

Predicting soil respiration using carbon stock in roots, litter and soil organic matter in forests of Loess Plateau in China

Understanding the dominant variables driving soil respiration is critically important for predicting soil CO2 emission and assessing the carbon balance of forest ecosystems. In a small catchment of the semiarid Loess Plateau in China, soil respiration and soil biophysical factors were studied on sites of five forest types, comprising plots established in a pure Pinus tabulaeformis plantation, a pure Robinia pseudoacacia plantation, a mixed P. tabulaeformis and R. pseudoacacia plantation, a pure Platycladus orientalis plantation, and a natural Populus davidiana stand. Soil temperature at the 10 cm depth was found to be the most predominant factor controlling the temporal pattern of soil respiration, accounting for 11–40% seasonal variation in the rate of soil CO2 efflux across forest types. By applying an empirical model and the calculated temperature sensitivity of soil respiration (Q10) and the rate of basal soil respiration (R10), annual soil CO2 emission was estimated separately for each forest type using the automatically monitored data of soil temperature at the 10 cm depth. The annual soil CO2 emission varied greatly with forest types and ranged from 647.71 g C m−2 y−1 in the P. orientalis plantation to 1448.50 g C m−2 y−1 in the natural P. davidiana stand. Annual soil CO2 efflux is better predicted by soil organic carbon content and the amount of carbon in roots, litter and top soil than soil temperature when data are pooled for all plots of the five forest types. A first order exponential analysis indicates that about 77% of the variation in annual soil CO2 efflux is explained by root carbon stock, 63% by the combined carbon stock in roots, litter, and top soil, and 48% by the combined carbon stock in litter and top soil. We conclude that annual soil CO2 efflux can be predicted by carbon pools in roots and soils rather than by soil temperature in watersheds where spatial variation in soil temperature is relatively small in the semiarid Loess Plateau of China.

Soil dynamics and carbon stocks 10 years after restoration of degraded land using Atlantic Forest tree species

Brazil’s Atlantic Forest ecosystem has been greatly affected by land use changes, with only 11.26% of its original vegetation cover remaining. Currently, Atlantic Forest restoration is receiving increasing attention because of its potential for carbon sequestration and the important role of soil carbon in the global carbon balance. Soil organic matter is also essential for physical, chemical and biological components of soil fertility and forest sustainability. This study evaluated the potential for soil recovery in contrasting restoration models using indigenous Atlantic Forest tree species ten years after their establishment. The study site is located in Botucatu municipality, São Paulo State-Brazil, in a loamy dystrophic Red-Yellow Argisol site (Typic Hapludult). Four treatments were compared: i) Control (Spontaneous Restoration); ii) Low Diversity (five fast-growing tree species established by direct seeding); iii) High Diversity (mixed plantings of 41 species established with seedlings) and; iv) Native Forest (well conserved neighboring forest fragment). The following soil properties were evaluated: (1) physical- texture, density and porosity; (2) chemical- C, N, P, S, K, Ca, Mg, Al and pH; (3) biological-microbial biomass. Litter nutrient concentrations (P, S, K, Ca and Mg) and C and N litter stocks were determined. Within ten years the litter C and N stocks of the Low Diversity treatment area were higher than Control and similar to those in both the High Diversity treatment and the Native Forest. Soil C stocks increased through time for both models and in the Control plots, but remained highest in the Native Forest. The methods of restoration were shown to have different effects on soil dynamics, mainly on chemical properties. These results show that, at least in the short-term, changes in soil properties are more rapid in a less complex system like the Low Diversity model than in the a High Species Diversity model. For both mixed plantation systems, carbon soil cycling can be reestablished, resulting in increases in carbon stocks in both soil and litter.

Greenhouse gas balance of harvesting stumps and logging residues for energy in Sweden

In this case study, forest fuel procurement chains of stumps and logging residues were evaluated using a Life Cycle Assessment perspective. Direct emissions from combustion were not included, but soil organic carbon change was included as changes in carbon stocks in litter and soil. The results showed that primary forest biomass for energy has a climate impact which is time dependent. However, in long-time perspectives, there are large greenhouse gas (GHG) savings. In a short-term (20 years), there were no GHG savings when natural gas or coal was replaced. This is due to the fact that the harvest lead to decreased input of organic matter to the soil which is compared to a reference where biomass are left to decompose. The reduction in soil organic carbon may have been underestimated in the stump harvest systems studied, as the effect of soil disturbance per se was not included. Important factors when assessing GHG balance of forest fuels, besides the time horizon used, were site productivity, geographical position and forest fuel resource (stumps or logging residues). When assessing the greenhouse gas savings, efficiency of the end-use, allocation method between heat and power and type of fossil fuel replaced were also important.

Including the effects of water stress on decomposition in the Carbon Budget Model of the Canadian Forest Sector CBM-CFS3

Decomposition of plant detritus and humified organic matter in terrestrial ecosystems is a primary source of atmospheric carbon dioxide (CO 2), yet the dynamics of decomposition are not well understood, particularly their response to climate change. The Carbon Budget Model of the Canadian Forest Sector (CBM-CFS3) presently includes a sub-model to simulate the decomposition of dead organic matter carbon pools using base decay rates modified by temperature quotients. In this study, representation of litter decomposition was improved in the CBM-CFS3 by reducing decay rates under limited moisture conditions. Water stress effects were determined from comparisons of model predictions with data from a 12-year national litterbag decomposition study—the Canadian Intersite Decomposition Experiment (CIDET). Several simple water-stress modifiers based on precipitation and potential evapotranspiration were tested, and parameters were simultaneously fit by minimizing the least-squared error. The best-fitting formulation used the annual average of the ratio of monthly precipitation to monthly potential evapotranspiration, and increased the explained variance by 8%. Water-stress modifiers were applied to decay rates to predict carbon stocks at 516 ground plots from a national soil plot database. The addition of the water-stress modifier modestly increased litter and humified organic matter carbon stocks at dry locations and decreased these carbon stocks at non-water-stressed locations. The new ability to lower decay rates of certain dead organic matter pools under limited moisture conditions in the CBM-CFS3 has the potential to reduce bias in carbon flux predictions for those regions and for future climate change scenarios where moisture limits decomposition processes.

Soc stock in different forest-related land-uses in central Stara planina mountain, Bulgaria

Forest conversions may lead to an accumulation of carbon in vegetation, but little is known about changes in soil C storage with establishment of plantation forests. Understanding these effects is important to addressing issues relevant to ecosystem function and productivity, and to global balance of carbon. The study investigated the effects of the created coniferous plantations on former beech and pasture sites on the soil organic carbon storage. The major forest-related land-uses in the high mountainous regions of central Stara Planina Mountain were investigated: mountainous pasture, coniferous plantations (planted on previous pasture and beech forests between four and five decades ago) and natural beech forests. The experimental data of soil properties, conducted in 2005, 2006 and 2007, were used in determining the variations in organic carbon storage in forest litter and in mineral soil under different land-use patterns. At each site five representative soil profiles were opened and described giving a total 75 soil samples from the soil layers respectively at 0-10, 10-30 and 30-50 cm depth. A total of 55 samples from forest floor layers (Aol, Aof, Aoh and greensward) were collected with 25:25 cm plastic frame. The main soil properties were determined in accordance with the standardized methods in the Laboratory of soil science at the Forest Research Institute - BAS. The IPCC Good Practice Guidance for Land Use, Land Use Change and Forestry was used to estimate the soil organic carbon stock in soil and litter. The results obtained showed that the SOC stock was quite similar among forest land-uses. The conversion of natural beech forests to coniferous plantations in studied region is related with slightly expressed decrease in soil carbon storage. The values of SOC stocks in 0-50 cm soil layer in these sites were 8.5 (?2.1) tones/ha for pine and 11.0 (?1.4) tones/ha for spruce, while under the natural beech forest it was 14.8 (?1.0) tones/ha. The SOC stock in mountainous pasture was 20.7 (? 6.5) tones/ha, while in spruce plantation created on previous pasture it was 13.5 (?2.7) tones/ha. Our finding showed that forest conversions effect in central Stara Planina Mountain is expressed by decrease in SOC stock related with losses of carbon from the upper mineral soil decades after creation of coniferous plantations. Nevertheless the relatively large organic carbon storage in forest litter in the spruce plantations compensated C lost from mineral soil after the land-use change. The overall carbon stock both in forest litter and soil under plantations ranged from 56 tones/ha (pine) to 77 tones/ha (spruce), while under natural beech forest and pasture the values were 70 and 81 tones/ha respectively. But in terms of stability C sequestrated in mineral soil is more desirable than C sequestrated in forest floor which are more vulnerable to decomposition following disturbances. The application of silvicultural activities in coniferous plantations created by conversion of forest lands or grasslands in the region of central Balkan is desirable to improve the carbon sequestration in soils.

Predicting chronosequential changes in carbon stocks of pachymorph bamboo communities in slash-and-burn agricultural fallow, northern Lao People's Democratic Republic

In northern Lao People's Democratic Republic, rising human population has drastically reduced the fallow period of slash-and-burn agriculture which has led to a considerable decrease in the carbon stock in these communities. We estimated chronosequential changes in the communities' carbon stocks, and established the relationship between the fallow period and fallow-period-average carbon stocks in three carbon pools of bamboo-dominated communities in hilly areas of the Luang Prabang Province, northern Lao People's Democratic Republic. Based on measurements by destructive sampling, we devised a model and root-to-shoot ratios for estimating bamboo biomass. In six secondary plant communities established after slash-and-burn cropping, we estimated community biomass using the above model and others, and measured deadwood and litter stocks. The communities' biomass and deadwood significantly increased with time after the last cropping and the former reached about 100 Mg ha−1 after 15 years, whereas litter stocks did not show significant trends over time. Extending the fallow period from 2 to 5 years would increase fallow-period-average carbon stock from 14.2 to 25.1 Mg C ha−1. The overstory height was significantly correlated with biomass, deadwood, and litter carbon stocks of these communities. Based on our findings, changes in a community's carbon stocks can be estimated using the changes in overstory height, which should be taken into account in future studies to reduce uncertainty in estimating carbon stocks in tropical ecosystems.

我が国の森林におけるリター・枯死木・土壌炭素蓄積量に関する全国調査

我が国の森林におけるリター・枯死木・土壌炭素蓄積量に関する全国調査

Small scale spatial variability of organic carbon stocks in litter and solum of a forested Luvisol

Soil organic carbon (OC) stocks are highly variable at the forest stand level. In order to analyse spatial variability at the stand scale, a study was conducted on a Luvisol developed from loess in Thuringia, Germany. At a 10,000 m 2 beech ( Fagus sylvatica L.) forest site, soil samples were taken at 54 points from the litter layer and the complete solum whose thickness varied between 0.24 m and 0.96 m. With a sampling scheme that incorporated a minimum horizontal sampling distance of 0.2 m, OC stocks in the litter layer and the solum were characterised by ordinary statistics and geostatistics. With respect to the vertical distribution of OC stocks, results showed that the OC stocks were 0.4 kg OC m − 2 in the litter layer, 3.0 kg OC m − 2 in the solum 0–0.12 m depth, and 4.5 kg OC m − 2 in the solum > 0.12 m depth. This highlighted the importance of subsoils in terrestrial carbon balances. No spatial pattern was observed in the litter layer, whereas semivariograms of OC stocks in the solum 0–0.12 m depth and the solum > 0.12 m depth exhibited a range of less than 5.4 m. The nugget variance accounted for around 20% of the sill in the solum 0–0.12 m depth and for over 40% of the sill in the solum > 0.12 m depth. These results emphasised the high small scale variability at the stand scale. Ordinary and spatial correlation indicated that the OC stocks are strongly affected by the thickness of the solum, whereas a relation between the distance to the nearest tree and the magnitude of OC stocks was not found. Considering the variability of the study area, the minimum detectable difference (MDD) of OC stocks for n = 9 was 0.3 kg OC m − 2 in the litter layer, 2.0 kg OC m − 2 in the solum 0–0.12 m depth, and 3.6 kg OC m − 2 in the solum > 0.12 m depth. At this site more than 300 samples would be required to detect a relative OC stock change of 10% in the solum.

Changes in organic carbon storage in a 50 year white spruce plantation chronosequence established on fallow land in Quebec

The objectives of this study were to assess the change in organic carbon (C) stocks in aboveground biomass, litter, and soil in a 50 year chronosequence of white spruce (Picea glauca (Moench) Voss) plantations established on non-regenerated fallow land in Quebec, and to determine the effects of ploughing (furrows) on these C stocks. Woody aboveground biomass was determined from dendrometric surveys and the use of allometric equations. The litter was sampled as well as the underlying soil in layers 10 cm thick down to 50 cm depth. The plantations under study were C sinks over the 50 year period, since they accumulated 75 Mg·ha–1 during this period, with the highest rate of C accumulation occurring in the woody aboveground vegetation between 10 and 35 years. The soil at 0–30 cm depth was a C source, mainly until the plantations reached 22 years of age, with an annual loss of 0.8% over 50 years. No difference was observed among the controls and site-preparation treatments. These results suggest that 22-year-old white spruce plantations, the oldest considered for the first commitment period of the Kyoto Protocol (2008–2012), would be a small C sink (12 Mg·ha–1) in southeastern Quebec but would become a larger sink for subsequent commitment periods.

Carbon stock assessment in old growth Pinus roxburghii Spreng. plantation of Forest Research Institute, New Forest, Dehra Dun, India

This paper deals with carbon stock in litter and soil of the old growth Pinus roxburghii (Pine) plantation. The Pine plantation was raised in the year 1926 and due to the mortality of Pine is being replaced by some broad-leaved species, in patches, constituting four plant communities. The study of these communities, viz. Pure Pine, Pine – Michelia, Mixed Pine and Pure Cinnamomum camphora community shows that carbon content and organic carbon percentage was higher in Pine-Michelia and Mixed Pine communities than in Pure Pine and Pure C. camphora communities, therefore it may be concluded that Pine plantation mixed with broad -leaved is beneficial in carbon stock as well as organic carbon percentage, the litter of mixed Pine forest with higher base content is less acidic, less able to complex on protein and much easier to decompose than acidic litter of Pure Pine forests.