Timber Stock Research Articles

Future management options for cembran pine forests close to the alpine timberline

Key messageHigh-elevation forests in the Alps protect infrastructure and human lives against natural hazards such as rockfall, flooding, and avalanches. Routinely performed silvicultural interventions maintain the required stand structure but are not commercially viable in remote forests due to high operational costs. Financial subsidies for the management of high-elevation protection forests are an efficient strategy to ensure sustainable forest cover.ContextPresently, many high-elevation forests in the Alps are managed in order to ensure the provision of ecosystem services with emphasis on the minimization of natural hazards.AimsWe studied the possible economic performance of a high-elevation protection forest from an owner’s perspective. We investigated whether the increase in productivity due to climate change and a favorable market for the dominating cembran pine (Pinus cembra L.) are sufficient for profitable timber production in protection forests.MethodsWe simulated the standing timber stock and the soil carbon pool for a 100-year period with climate-sensitive models and compared harvesting costs with expected revenues. Our scenarios included different climates, intensities of timber extractions, parameters of the timber market, and the availability of government subsidies.ResultsOverall, the productivity of forests increases by approximately 15% until the end of the century. In a zero-management scenario, the forest accumulates carbon both in the aboveground biomass and the soil. In the case of an extensive management with moderate timber extractions every 50 years, the carbon stocks decline both in biomass and soil. A more intensive management scenario with extractions every 30 years leads to substantial losses of the soil and biomass carbon pools. In addition, the stand structure changes and the protective function of the forest is not sustainably ensured. Timber production can be economically successful only with high selling prices of cembran pine timber and the availability of governmental subsidies for forest management. The admixed European larch (Larix decidua Mill.) contributes only marginally to the economic success. The main challenge are harvesting costs. The costs of timber extraction by a long-distance cableway logging system exceed the value of the harvested timber.ConclusionThe intensification of forest management cannot be recommended from the perspective of timber production, sustainable forest management, and protection against natural hazards. Our simulation experiment shows that the extraction of timber at decadal intervals depletes the carbon stock that is insufficiently replenished from aboveground and belowground litterfall. Leaving the forest unmanaged does not impose a particular threat to stand stability and is under the encountered situation, a justified strategy.

Taper and Volume Systems Based on Ratio Equations for Pinus pseudostrobus Lindl. in Mexico

Studies on functional relationships between relative stem diameter and height to estimate timber yield are useful in the management of commercial forest plantations. With taper analysis data of 42 Pinus pseudostrobus Lindl. trees in the indigenous community of Nuevo San Juan Parangaricutiro , Michoacan, Mexico, six compatible systems for predicting taper (d), merchantable volume (Vm), stem volume (Vs), total tree volume (Vt) and branch volume (Vb) were fitted and evaluated. The compatible taper and merchantable volume equations were based on volume ratio equations. Three Vs equations were tested in each system. In general, the compatible systems presented statistical accuracy in the d, Vm, Vs and Vt components but were less accurate in Vb. Three compatible systems were selected, according to their more efficient goodness-of-fit statistics, and a different total volume equation was incorporated into each system. The compatible systems based on volume ratio equations are simple, reliable tools for estimation of stand timber stocks and product classification of P. pseudostrobus in commercial forest plantations in Mexico.

Trade-offs between carbon stocks and timber recovery in tropical forests are mediated by logging intensity.

Forest degradation accounts for ~70% of total carbon losses from tropical forests. Substantial emissions are from selective logging, a land-use activity that decreases forest carbon density. To maintain carbon values in selectively logged forests, climate change mitigation policies and government agencies promote the adoption of reduced-impact logging (RIL) practices. However, whether RIL will maintain both carbon and timber values in managed tropical forests over time remains uncertain. In this study, we quantify the recovery of timber stocks and aboveground carbon at an experimental site where forests were subjected to different intensities of RIL (4, 8, and 16trees/ha). Our census data span 20years postlogging and 17years after the liberation of future crop trees from competition in a tropical forest on the Guiana Shield, a globally important forest carbon reservoir. We model recovery of timber and carbon with a breakpoint regression that allowed us to capture elevated tree mortality immediately after logging. Recovery rates of timber and carbon were governed by the presence of residual trees (i.e., trees that persisted through the first harvest). The liberation treatment stimulated faster recovery of timber albeit at a carbon cost. Model results suggest a threshold logging intensity beyond which forests managed for timber and carbon derive few benefits from RIL, with recruitment and residual growth not sufficient to offset losses. Inclusion of the breakpoint at which carbon and timber gains outpaced postlogging mortality led to high predictive accuracy, including out-of-sample R2 values >90%, and enabled inference on demographic changes postlogging. Our modeling framework is broadly applicable to studies that aim to quantify impacts of logging on forest recovery. Overall, we demonstrate that initial mortality drives variation in recovery rates, that the second harvest depends on old growth wood, and that timber intensification lowers carbon stocks.

Forest plantations and climate change discourses: New powers of ‘green’ grabbing in Cambodia

Efforts to combat global climate change through forestry plantations designed to sequester carbon and promote sustainable development are on the rise. This paper analyses the trajectory of Cambodia´s first large-scale reforestation project awarded within the context of climate change mitigation. The 34,007 ha concession was formally conceived to promote sustainable resource use, livelihood improvements and emission reduction. On the ground, however, vast tracks of diverse forest landscapes are being cleared and converted to acacia monocultures, existing timber stocks are logged for market sale, and customary land users dispossessed from land and forest resources. While the project adds to an ongoing land grab crisis in Cambodia, we argue that the explicit environmental ends of the forestry concession enabled a ‘green grab’ that not only exceeds the scale of land grabs caused by conventional economic land concessions, but surprisingly also exacerbates forest logging and biodiversity loss in the area. This case demonstrates the extent to which current climate change discourses, forestry agendas and their underlying assumptions require critical revision in global policy discussions to forestall the growing problem of green grabbing in land use.

Estimadores de muestreo para inventario de plantaciones de Pinus chiapensis (Martínez) Andresen

La evaluación de plantaciones forestales comerciales (PFC) requiere de herramientas cuantitativas precisas (estimadores de muestreo) para conocer las existencias maderables, generar información confiable para planificar acciones y tomar las mejores decisiones en el manejo sostenible de los recursos forestales. En este contexto, se planteó el objetivo de comparar cuatro estimadores para plantear una estrategia eficiente de muestreo que permita calcular las existencias maderables de Pinus chiapensis en una plantación forestal comercial (PFC), en el municipio Tlatlauquitepec, Puebla. Para cuantificar el inventario de las plantaciones de Pinus chiapensis se utilizó la información dasométrica (D y H) de 44 parcelas permanentes de muestreo, establecidas en 2014 en una superficie de 87 ha y remedidas en 2015. Se evaluaron dos estimadores clásicos basados en diseños: Muestreo Simple al Azar (MSA) y Muestreo Estratificado (ME), así como dos basados en modelos: Estimadores de Razón (ERaz) y Estimadores de Regresión (EReg), estos últimos emplean una media poblacionalestimada bajo ME. Los resultados indican que los cuatro estimadores son estadísticamente diferentes y muestran que el EReg es más preciso para estimar las existencias en volumen al emplear como variable auxiliar el área basal. El EReg permitió actualizar el inventario de un total de 4 806 m3 para el primer año de medición, a 6 496 m3 en el segundo año. En el ERaz (V2/V1) bajo ME se obtiene una Razón (R) del volumen dos (2015) entre el volumen uno (2014) que sugiere un incremento porcentual de 35 % del volumen para 2015.

Validating the predicted saw log and pulpwood proportions and gross value of Scots pine and Norway spruce harvest at stand level by Most Similar Neighbour analyses and a stem quality database

Detailed pre-harvest information about the volumes and properties of growing stocks is needed for increased precision in wood procurement planning for just-in-time wood deliveries by cut-to-length (CTL) harvesters. In the study, the non-parametric Most Similar Neighbour (MSN) methodology was evaluated for predicting external quality of Scots pine and Norway spruce, expressed as stem sections fulfilling the saw log dimension and quality requirements of Finnish forest industry, as they affect the recovery of timber assortments and the value of a pre-harvest stand. Effects of external tree quality were evaluated using saw log recovery and saw log reduction caused by stem defects, as well as total timber value (€) and average unit value (€ m) in a stand. Root mean square error (RMSE) of saw log recovery and reduction were 9.12 percentile points (pp) for Scots pine and 6.38 pp for Norway spruce stands. In the unit value considerations, the predictions compared with measurements resulted in the RMSE of 3.50 € m and the bias of 0.58 € m in Scots pine stands and 2.60 € m, and 0.35 € m in Norway spruce stands, respectively. The presented MSN based approach together with the utilization of the external stem quality database included in the ARVO software could provide dimension and external quality predictions usable for pre-harvest assessment of timber stock at a stand level. This prediction methodology is usable especially in analyses where timber assortment recoveries, values and unit prices are compared when different bucking objectives are used.–3–3–3–3–3

Структура осинников Закамья Республики Татарстан

Приведены результаты исследований, отражающие характер распределения осинников Закамья Республики Татарстан по типам лесорастительных условий, возрасту, запасу стволовой древесины, классам бонитета и полноте The article focuses on the low forest cover of the Republic of Tatarstan, the need to maintain a regional forest resource base, the prospects for increasing the economic potential of forests without compromising their environmental functions. As one of the ways to achieve this goal, the prospects of increasing the productivity of the aspen formations of the Republic of Tatarstan through their reconstruction are considered. For the subsequent development of a complex of forestry measures for qualitative improvement of aspen trees, it is proposed to study the structural organization of the aspen. In this case, the example of the physical and geographical region of Zakamye of the Republic of Tatarstan. The specificity of this work is that the study of the area of the aspen propagation of Zakamye of the Republic of Tatarstan, the accumulation of the timber stock, the characteristics by class of bonitet and relative completeness – was carried out in the context of types of forest conditions by age groups. As a result, an informative set of data on the age structure of the aspen formations of Zakamye of the Republic of Tatarstan, the features of their localization in various types of forest habitat conditions, the laws of accumulation of wood volume was obtained. In the context of the types of forest growing conditions and groups of ages, characteristics of aspen plantations according to bonitet classes and relative completeness are given. The obtained information serves as a good information base for development of scientific and production solutions aimed at improving the ecological and resource potential of forests and, in particular, aspen formations of the Republic of Tatarstan.

ECOLOGICAL STRUCTURE OF BEECH AND CONIFEROUS/BEECH MOUNTAIN CLIMAX FOREST STANDS OF UKRAINIAN CARPATHIANS

According to the age classes, middle-aged forest stands predominate in the mountan forests of the Carpathians (46.2), overmature stands occupy 6.9% (62 thousand ha). According to the recent inventory, about 85 thousand hectares of climax old-growth forests are identified, including climax virgin forests that occupy about 54 thousand hectares which are uneven-aged. For their identification, a population matrix with a division into age groups is suggested, taking into account the age condition of the edificator. There are 6 age groups: pre-generative – juvenile-immature, virginal; generative – young generative, middle-aged, mature and old generative. In terms of the number of uneven-aged beech and coniferous/beech stands, the adequate cenopopulations of beech is dominated. The age spectra of fir and spruce, sycamore maple, ash-tree are generally non-stabilized or fragmentary. On average, on 1 ha of elementary demographic cenopopulation of beech and coniferous/beech stands on the generative generation there are 174-235 beech individuals, 42-52 – fir, 5-16 – spruce, 5-10 – sycamore and ash-tree, respectively.Half of the timber stock (50-60%) is over-mature, and 25% is in mature age condition. In climax cenosis, it can be recommended to conduct a uniform or non-uniform selection felling system. Introduction of population paradigm in forest synecology opens up a new opportunity to divide stands into age generations and treat them as a set of cenopopulations of key species for old-growth forests and virgin forests.

Вікова структура різновікових букових деревостанів Українських Карпат та особливості нагромадження ними запасу

Запропоновано результати досліджень вікової структури та динаміки нагромадженого запасу різновіковими буковими деревостанами в Українських Карпатах. Проаналізовано різновікові деревостани двох категорій: у яких здійснено головне рубання, і в яких головне рубання не проектується. Розглянуто об’єкти із різною кількістю поколінь лісу. Кількість поколінь лісу змінюється від двох до п’яти.
 Прогноз нагромадженого запасу диференційовано за поколіннями лісу та подано в інтегрованому вигляді в цілому для деревостану. Період прогнозу прийнято в межах від 0 до 320 років. Середній вік найстаршого (першого) покоління лісу поточного циклу збігається із числовою величиною періоду прогнозу запасу. Середній вік інших поколінь лісу зміщений відносно періоду прогнозу запасу. Цей показник вирахувано за наведеним у науковій праці алгоритмом. Запас покоління лісу обчислено за моделлю параболи другого порядку, аргументом котрої є вік.
 Для рядів прогнозу теоретичних значень запасу різновікових букових деревостанів із різною кількістю поколінь лісу та режимом лісовикористання обчислено основні статистики. Йдеться про середній запас деревостану, вирахуваний загалом для періоду прогнозу, а також стандартне відхилення запасу, коефіцієнт мінливості запасу та максимальні (мінімальні) відхилення запасу від середньої його величини.
 Враховуючи амплітуду запасу та інші статистики, за оптимальну модель прийнято різновіковий буковий деревостан, який складається із 4-5 поколінь лісу.

The impact of climate change and aquatic salinization on mangrove species in the Bangladesh Sundarbans

This paper investigates the possible impacts of climate change on aquatic salinity and mangrove species in the Bangladesh Sundarbans. The impact analysis combines the salinity tolerance ranges of predominant mangrove species with aquatic salinity measures in 27 scenarios of climate change by 2050. The estimates indicate significant overall losses for Heritiera fomes; substantial gains for Excoecaria agallocha; modest changes for Avicennia alba, A. marina, A. officinalis, Ceriops decandra, and Sonneratia apetala; and mixed results for species combinations. Changes in mangrove stocks are likely to change the prospects for forest-based livelihoods. The implications for neighboring communities are assessed by computing changes in high-value mangrove species for the five sub-districts in the Sundarbans. The results of the impact analysis indicate highly varied patterns of gain and loss across the five sub-districts. Overall, however, the results suggest that salinity-induced mangrove migration will have a strongly regressive impact on the value of timber stocks because of the loss of highest value timber species, Heritiera fomes. In addition, the augmented potential for honey production will likely increase conflicts between humans and wildlife in the region.

Cenopopulation structure of climax forest stands of formation of beech forests in Ukrainian Carpathians

Logging in the mountainous conditions of the Carpathians has transformed the forest cover into a continuous succession system. Climax exemplary communities which are subject to protection and research according to the position of structure and dynamics on the population methodological basis, to have survived on an insignificant area in the reserves and protective categories of forests. The cenopopulation paradigm considers the edificator species (spruce, fir, beech, pine) as a system of interacting geographic, food and elementary populations. The structure of climax uneven-aged coenopopulations of formation of the beech forest is considered as natural climax cenoses that have arisen as a result of endo- or exogenous successions due to climatic and edaphic conditions. Their dynamic equilibrium is supported by the variability of the spatial mosaic structure through the age-old turnover of generations. The distribution of trees by diameter in climax forest stands is characterized by three types: reverse s-shaped, j-shaped and bell-shaped with right-sided asymmetry. The inverse s-type distribution type is the main one and occupies 77 % of trial plots. The types of reverse j-shaped and bell-shaped with right-side asymmetry are encountered respectively in 2 and 21 % of the trial plots. Vertical stratification in climax beech cenoses distinguishes four functional tiers-horizons, or spatial ecological niches. There is a possibility to forecast the directions of successions by species composition in tiers. In mixed dark-coniferous-beech stands, the beech occupies a dominant position, and fir, and especially spruce, a regressive position. The age structure of climax forest stands is presented to 6 age groups: pre-generative - juvenile and imature and virginal; generative – young, middle-aged, ripe and old (overmature). According to number of climax coniferous/beech and beech stands the full-member beech cenpopulations predominate. The age spectra of fir and spruce, maple-sycamore, ash, and elm are usually unequal, or fragmentary. On average, one hectare in climax coniferous/beech and beech stands include 174–235 individuals of generative generation – 42–52 – fir, 5–16 – spruce, 5–10 – maple-sycamore and ash tree. The timber stock in half (50–60 %) is concentrated in overmature and 25 % in mature age condition. Introduction of the population paradigm in forest synecology discover a new opportunity to divide the stand of the age generation and treat them as old-growth forests and virgin forests which form a set of key species of cenopopulations, and also determine the direction of succession.

Assessment of enrichment planting of teak (Tectona grandis) in degraded dry deciduous dipterocarp forest in the Central Highlands, Vietnam

After years of unsustainable logging, dry deciduous dipterocarp forest (DDDF) has become poor in timber stocks and has been converted to industrial crops such as rubber. The objectives of this study were to assess teak (Tectona grandis L.f.) tree establishment under degraded DDDF conditions and to determine factors that influence the suitability of teak as a forest enrichment tree species. A set of 64 experimental plots of 4 900 m2 each was set up and observed for 4–5 years for testing enrichment planting with teak under various combinations of two groups of factors: ecological conditions and forest status. Weighted, non-linear, multivariate regression models were used to detect key factors that influenced the suitability of teak. The results showed that at the age of 4 years the average dominant tree height (defined as 20% of the tallest trees in the experimental plot) reached 11.2, 7.8, 5.3 and 3.8 m for very good, good, average and poor suitability levels, respectively. Survival rates of planted teak from average to very good suitability levels were over 90%. Six key factors that affected the suitability of teak were waterlogging during the rainy season, altitude, stand volume of the degraded DDDF, soil type, percentage of sand and concentration of P2O5 in the soil. Under the extreme ecological and environmental conditions of the DDDF, enrichment planting with teak gave promising results.

Floristic and structural changes in secondary forests following agricultural disturbances: the case of Lama forest reserve in Southern Benin

Structural changes in secondary forests are less known in West Africa, and this precludes their management. This study aims at providing quantitative information on floristic composition and structure of the Lama secondary forests (Benin), so as to contribute to their restoration, and fill part of knowledge gaps on West African secondary forests. Data of 77 permanent plots each of 0.5 ha were used to analyze the floristic composition, the trajectory of the recovery and the recovery of stocking in these forests, compared to nearby old-growth forests. The results showed that the forests were less diversified with few species very common in the forest stands; the most dominant were Lonchocarpus sericeus and Anogeissus leiocarpa in the secondary forests, and Dialium guineense , Diospyros mespiliformis and Afzelia africana in the old-growth forests. The secondary forests hold more species than the mature ones. Their compositions will recover that of the original forest because species of the original forest were actively regenerating in the secondary forests. About 28 years after recovery, large trees were insufficient and basal area was about 60% of those of the mature forests. Further studies are needed to elucidate barriers to tree regeneration and dynamics of tree population. © 2016 International Formulae Group. All rights reserved. Keywords: Secondary forest, recovery, diversity, species composition, timber stock, Benin

Divergent trends in ecosystem services under different climate-management futures in a fire-prone forest landscape

While ecosystem services and climate change are often examined independently, quantitative assessments integrating these fields are needed to inform future land management decisions. Using climate-informed state-and-transition simulations, we examined projected trends and tradeoffs for a suite of ecosystem services under four climate change scenarios and two management scenarios (active management emphasizing fuel treatments and no management other than fire suppression) in a fire-prone landscape of dry and moist mixed-conifer forests in central Oregon, USA. Focal ecosystem services included fire potential (regulating service), timber volume (provisioning service), and potential wildlife habitat (supporting service). Projections without climate change suggested active management in dry mixed-conifer forests would create more open forest structures, reduce crown fire potential, and maintain timber stocks, while in moist mixed-conifer forests, active management would reduce crown fire potential but at the expense of timber stocks. When climate change was considered, however, trends in most ecosystem services changed substantially, with large increases in wildfire area predominating broad-scale trends in outputs, regardless of management approach (e.g., strong declines in timber stocks and habitat for closed-forest wildlife species). Active management still had an influence under a changing climate, but as a moderator of the strong climate-driven trends rather than being a principal driver of ecosystem service outputs. These results suggest projections of future ecosystem services that do not consider climate change may result in unrealistic expectations of benefits.

Some Features of Forest Stands Growth and Development on Distributed Lands of Novyj Rozdil Sulphur Quarry Dumps

Intensive mining in the mid-twentieth century within Western Ukraine territory led to destruction of large areas of the ground, vegetation and soils. Such lands are marked by lack of fertile layer with dramatically altered topography and hydrological regime, worsening sanitary conditions of industrial areas and negatively affect on the ecological state of surrounding farmlands and other areas. Accelerating the process of natural regeneration of vegetation, giving it a certain direction, forming productive and sustainable biogeocenosis which are characterized by high aesthetics, conservation and economic value will allow solving current tasks. The authors have conducted the study of growth and development of forest stands on disturbed lands of dumps of Novyj Rozdil sulfur quarry. Firstly, we have revealed that the most productive are poplar stands that showed the highest averages height and diameter, lower reserve of timber. They are characterized by mixed stands featuring black alder, cherry, ash and aspen and the least productivity reaches oak stands with little admixture of black alder and aspen. We have noted that black alder in elm stand is characterized by the highest impedance and the lowest capacitance values of polarization. Significantly lower impedance is in the sample oak plantation, cherry and elm plantation. Growth and development of tree species in analyzed forest stands significantly affects the physical-chemical and chemical properties of the soil, contributes to the reproduction of sois, organic matter accumulation, and supersedes acidity. Secondly, high humus content at the top soil layer is defined in the section of stand composition 6E1O1Ch1Al1Ac and on the section of stands 6O2Al2Os + 1W. Increased humus content is also observed in the top layer of soil on the section of stand composition 10P + Ch and average degree of humus is observed on the sections of stand composition 6A3Ch1As + A. Based on the research we have made the following conclusions. The highest productivity in the dumps of Novyj Rozdil sulfur quarry is shown by poplar stands, a smaller timber stock has mixed stands featuring black alder, cherry, ash and aspen, and the least performance is characterized by oak stands with little admixture of black alder and aspen. Average degree of phosphorus provision is noted in the top (up to 0.10 cm) layer of the soil on section with ash-cherry-alder-oak stands. A very low level of availability of phosphorus in analyzed soil horizon is noted on section of poplar and elm stand.

Quantifying uncertainty about forest recovery 32-years after selective logging in Suriname

The inclusion of managed tropical forests in climate change mitigation has made it important to find the sustainable sweet-spot for timber production, carbon retention, and the quick recovery of both. Here we focus on recovery of aboveground carbon and timber stocks over the first 32years after selective logging with the CELOS Harvest System in Suriname. Our data are from twelve 1-ha permanent sample plots in which growth, survival, and recruitment of trees ≥15cm diameter were monitored between 1978 and 2012. We evaluate plot-level changes in basal area, stem density, aboveground carbon, and timber stock in response to average timber harvests of 15, 23, and 46m3ha−1. We use a linear mixed-effects model in a Bayesian framework to quantify recovery time for aboveground carbon and timber stock, as well as annualized increments for both. Our statistical models accounted for the uncertainty associated with the height and biomass allometries used to estimate aboveground carbon and increased precision of annualized aboveground carbon increments by including data from forty-one plots located elsewhere on the Guiana Shield. The probabilities of aboveground carbon recovery to pre-logging levels 32years after harvests of 15, 23 and 46m3ha−1 were 45%, 40%, and 24%, respectively. Net aboveground carbon increment for logged forests across all harvest intensities was 0.64MgCha−1yr−1, more than twice the rate observed in unlogged forests (0.26MgCha−1yr−1). The probabilities of timber stock recovery at the end of the 32-year period were highest after harvest intensities of 15 and 23m3ha−1 (with 80% probability) and lowest after the harvest of 46m3ha−1 (with 70% probability). Timber stock recovery across all harvest intensities was driven primarily by residual tree growth. Application of the legal cutting limit of 25m3ha−1 will require more than 70 and 40years to recover aboveground carbon and timber stocks, respectively, with 90% probability. Based on the low recruitment rates of the twelve species harvested, the 25year cutting cycle currently implemented in Suriname is too short for long-term timber stock sustainability. We highlight the value of propagating uncertainty from individual tree measurements to statistical predictions of carbon stock recovery. Ultimately, our study reveals the trade-offs that must be made between timber and carbon services as well as the opportunity to use carbon payments to enable longer cutting rotations to capture carbon from forest regrowth.

Effects of silvicultural intensification on timber yields, carbon dynamics, and tree species composition in a dipterocarp forest in Kalimantan, Indonesia: An individual-tree-based model simulation

Nature conservation through sustainable forest management is challenged in the tropics by unnecessarily destructive but selective logging and diminishing timber yields. Silvicultural treatments beyond reduced-impact logging are often recommended to increase timber stocking, tree growth, and profits. Despite lack of large-scale and long-term scientific support, Indonesia has embarked on large-scale silvicultural intensification. To fill this information gap, we assessed the timber, carbon, and tree species composition consequences of different silvicultural practices in dipterocarp forests in Kalimantan, Indonesia.With data from 30 1-ha sample plots monitored for up to 20years after silvicultural intervention coupled with a new forest growth and yield model simulation (SILFOR), we evaluated the long–term consequences of the following silvicultural practices: once logged with a minimum cutting diameter (MCD) of 60cm (L60); once logged followed by under-planting with seedlings of commercial timber species (L60UP); twice logged with MCDs of 60cm and then 40cm (L60L40); and, twice logged followed by strip planting along cleared lines (L60L40SP).The results indicate that timber yields will not be sustained by L60 or L60L40 even if cutting cycles are extended from the current minimum of 30years to 60years. In contrast, yields from enrichment planted logged-over forests will recover to levels higher than the first cut if cutting cycles are extended to 50years for L60UP and to 40years for L60L40SP. Under these intensive silvicultural regimes, biomass carbon stocks also recover to primary forests levels, but with increased representation of commercial species. Although silviculturally successful, the financial consequences of these approaches to management intensification remain to be scrutinized.

A Forest Growth Model for the Natural Broadleaved Forests in Northeastern Korea

While a large sum of timber stock in private forests, especially broadleaved forests, has been ignored by their owners, a rising global concern about climate change and ecosystems has led to a renewed interest in natural broadleaved forest management strategies. This study establishes the forest growth model for the natural broadleaved forest of Gangwon-do based on the matrix model developed by Buongiorno and Michie. The matrix model by Buongiorno and Michie has been widely applied to study forest population dynamics, especially for uneven-aged forests. To develop an existing matrix model, our approach applies transitional probabilities of forest stands which are calibrated using National Forest Inventory data. Both long and short-term predicted simulation results show that the predicted average tree density and diameter distribution from our model are very close to the stand density and diameter distribution from observed data. Although the model simplifies reality, the results from our study confirm that our models are valid enough to predict the average stand status of the broadleaved forests in Gangwon-do.

Floral Composition and Timber Stock of Forest In The Samar Island Natural Park

Samar Island Natural Park (SINP) is the most important biodiversity refuge Samar Island. This assessment characterized floral diversity status in SINP and provided recommendations on how such resources can be better managed and protected against destruction. Five watersheds, namely: Taft, Can-avid, Basey, Suribao and Catubig were sampled. In each watershed, a transect line with 25 plots spaced at 200 m interval was used in the survey. Plot size was 20m x 20m. Trees 10 cm in diameter at breast height (DBH) and bigger were measured for stem diameter, merchantable height and tree height. This was for computation of timber volume. The species composition in 3 vegetative layers, such as tree layer, undergrowth and ground layer, was determined using the standard Braun-Blanquet methodology. The forest stands in the five watersheds was dominated by dipterocarp species. Of the 212 timber tree species in the tree layer, 35 species had diameter of at least 60 cm. Eighty-six percent of individual trees were dipterocarps, in 14 species. Shorea squamata and Shorea polysperma was the most frequent. Non-dipterocarp species dominated in number at the lower DBH range, particularly in the 10-20 cm and 21-40 cm DBH range. The forest of Samar still has high volume of commercial-size timber. Forests in the 5 watersheds differed in species composition and structure. The absence of access roads to interior barangays contributed to the conservation of forests. The transport system, such as presence of access road and connecting transport facilities to the main roads had influence to the degree of poaching activities. Areas that had access only through motorboats in shallow river had lowest incidence of poaching.

Agroforestry and ritual at the ancient Maya center of Lamanai

Paleoethnobotanical data retrieved from caches of Late Classic to Early Postclassic origin at the ancient Maya site of Lamanai, Belize, revealed carbonized maize kernels, cob fragments, common beans, coyol endocarps, and an abundance of wood charcoal, from both conifer and hardwood tree species. Pinus caribaea (Caribbean pine) was the most ubiquitous species in the Late and Terminal Classic sample set and the weight of Lamanai pine wood charcoal was more than the combined weight of all known archaeobotanical collections from nearby contemporaneous sites. Pollen data from northwestern Belize showed that the pine pollen signature declined during the Late Classic period, a trajectory in keeping with intensive exploitation of the nearby pine savannas as suggested by the contents of Lamanai caches examined in this study. Although Lamanai flourished far into the Postclassic period, pine charcoal use—based on present evidence—declined in Early Postclassic ritual contexts. Concomitantly, an increase in the local pine pollen rain indicated that pine timber stocks rebounded during the Postclassic period. The observed intensive use of pine at Late Classic Lamanai combined with a concurrent decline in the regional pine pollen signature is consistent with a hypothesis of over-exploitation of pine during the Late to Terminal Classic period.