Timber Species In Forests Research Articles

Goupia glabra não recupera seu estoque de madeira após um ciclo de corte de 35 anos na Amazônia brasileira: evidências de monitoramento de longo prazo em múltiplas áreas

ABSTRACT Single-rule management is often adopted for various tropical forest timber species due to limited knowledge on species-specific growth and the relationship between logging intensity and recovery time. This study provides information to support sustainable management of Goupia glabra by simulating its wood stock recovery over a 35-year period following logging using data from six areas in the Brazilian Amazon. Monitoring periods after the first harvest cycle varyed from 16 to 29 years, and logging intensity from 0.000 to 0.696 m² ha-1. Tree density of G. glabra varied from 0 to 22 trees ha-1 and dominance from 0.00 to 7.39 m² ha-¹. Frequency of tree diameters was almost evenly distributed across diameter classes, slightly higher in the first (20-30 cm) class. These parameters generated estimations of recovery rate from 12 to 85%, showing that 35 years is insufficient for trees with DBH ≥ 20 cm in all study areas to grow and replace the stock of trees with DBH ≥ 50 cm harvested during the first cycle. Minimum recovery periods from 48 to 83 years were estimated to guarantee the recovery of the wood stock in the study areas. These findings reinforce the need to adapt management rules according to the population dynamics of each timber species and each logging area, and suggest the need for changes in the current legal requirements that define forest management in the Amazon.

Combining the light-demanding Araucaria angustifolia with the shade-tolerant Cabralea canjerana: mixed plantations to produce tropical timber trees outside the Atlantic rainforest

Many trees of high timber value require canopy cover to become established, and at present, they are only harvested from native rainforests. Other species require high radiation to establish and can be planted in monospecific stands. The main question was whether the canopy generated by a light-demanding rainforest species could protect mid-successional timber species from high radiation and extreme temperatures. We evaluated the establishment of Cabralea canjerana under the canopy of Araucaria angustifolia stands. We related growth to the number of neighbors to determine the best positions to plant C. canjerana. In one stand, we measured environmental and physiological traits, and we determined that the seedling did not suffer light or water stress. Cabralea canjerana plant establishment was successful in stands of different basal areas, and trees reached the highest growth with up to two A. angustifolia neighbors within a 5 m radius. Therefore, the number of neighbors is a tool to choose the planting location to convert even-aged to uneven-aged mixed stands. In this way, valuable native timber species that require canopy protection during the first few years can be planted outside the rainforest. This is the first report of an uneven-aged mixed plantation of two Atlantic forest timber species.

Genetic variability and predicted gain in progeny tests of native Atlantic Forest timber species: Cariniana legalis, Cordia trichotoma, and Zeyheria tuberculosa

Over the years, the Atlantic Forest has been one of the biomes most affected by fragmentation and despite the scarcity of studies related to their genetic and breeding aspects, native Atlantic Forest species can provide various high-quality timber products. In this context, the objectives of this work were to estimate genetic parameters and predict genetic gain with selection of provenance/progeny tests of Cordia trichotoma, Zeyheria tuberculosa, and Cariniana legalis, for diameter at breast height (DBH) and survival rate. Seed trees from different provenances were selected and measured, and their seeds were collected and tested in the areas of Porto Seguro - Bahia state, Brazil. All test individuals were evaluated for DBH (cm) survival rate (%) and stem straightness. The variance components and genetic parameters were estimated for DBH and survival rate. The narrow-sense individual heritability (h2i) for DBH of the three species ranged from 0.26 to 0.72, showing moderate to high genetic control. However, based on the likelihood ratio test (LRT) there is no genetic variability among genotypes of Z. tuberculosa. For survival rate, high genetic control (0.54) was observed only for C. trichotoma, while for C. legalis and Z. tuberculosa h2i value was 0.11 and 0.0, respectively. After genetic parameter analyses, the expected genetic gains were estimated for seed trees, potential genitors and potential clones. For seed trees, gains based on the additive genetic values (u+a) for DBH by selecting the top 10 individuals of each species per family ranged between 17.17 and 30.31%. In the case of potential genitors, by selecting the top ten individuals based on u + a value, are expected gains between 19.17 and 49.65%. The ranking of the top ten potential clones based on genotypic values (u +g) for each species showed gains between 32.43 and 56.53%. Conducting genetic breeding for C. trichotoma and C. legalis presents high potential of genetic gains and efforts should be taken into account for supporting breeding strategies for those species. In the case of Z. tuberculosa, the absence of genetic variability seems to be a result of the Atlantic Forest deforestation and genetic basis narrowing.

Genetic variability and predicted gain in progeny tests of native Atlantic Forest timber species: Cariniana legalis, Cordia trichotoma, and Zeyheria tuberculosa

Genetic variability and predicted gain in progeny tests of native Atlantic Forest timber species: Cariniana legalis, Cordia trichotoma, and Zeyheria tuberculosa

Physiological responses of saplings of rainforest timber species differing in successional group to light regimes and nitrogen

ABSTRACTSaplings of 19 valuable rain forest timber species representative of three successional status groups (early secondary, late secondary and climax) were grown in a polyhouse to examine their responses to three light intensity/quality treatments and nitrogen supply. Solar radiation was modified using painted polyethylene sheet to mimic natural light environments across a rain forest vertical column as follows: 1. Transparent plastic, 80% of full sunlight, R:FR = 0.95, 2. Blue shade, 14% of full sunlight, R:FR = 0.69; 3. Green shade, 7% of full sunlight, R:FR = 0.50. Transparent plastic conditions promoted an increase in stem height and diameter (i.e., growth), leaf thickness and gas exchange per unit leaf area. Additional nitrogen availability enhanced growth and specific leaf area (i.e., leaves were thinner), particularly in the full sun environment and on early secondary and late secondary successional species, but did not influence photosynthetic rate. Successional status of the species did not affect photosynthetic rate although early secondary successional species grew faster and had fewer branches than species of the other successional groups. We recommend that for a successful mixed stand the high-light requiring species should be planted first, with increased nitrogen supply, and the shade tolerant species should be introduced later with no extra nitrogen supply required.

The prospect of micropropagating Gonystylus bancanus (Miq.) Kurz, a tropical peat swamp forest timber species through tissue culture technique - Review

Gonystylus bancanus (Miquel) Kurz is one of the most valuable timber species in tropical peat swamp forest. Its timber is widely used for furniture, decorative cabinets and interior decoration. Due to its higher demand, G. bancanus continues to be harvested which leads to its disappearance in the wild. This is worsened by the fact that germination rates in the wild are very poor due to rapid insect and fungal infestation. Even though vegetative propagation via stem cuttings has been successful, proper protocols on tissue culture need to be explored as a viable way of mass production of a large number of planting stock in a relatively shorter time for forest rehabilitation and enrichment planting purposes.

Domestication Performance of Indigenous Trees: A Decade of Rainforestation Experience in Degraded Karst Lands

This study tested the domestication potential of 43 indigenous timber species in 1.2-ha degraded karst land. Survival, height and diameter growth performance and site factors were periodically monitored. Results showed twenty-eight indigenous forest timber species thriving in an open karst area including 8 dipterocarps: narig, mayapis, white lauan, bagtikan, guisok-guisok, kalunti or manggasinoro, red lauan and yakal-kaliot. The non-dipterocarps include bitanghol & kalingag. Species with 100% survival were aniam gubat, bayokbok, ipil, kalumpit, lamog, puso-puso, sagimsim and taluto. White lauan had a survival of 96% and molave had 92%. Kalumpit had the highest increment both in height and diameter. Kalumpit was followed by dao, duguan, milipili. Among the dipterocarps, white lauan got the highest diameter and height growth increment. Narig, with its waxy leaf surface of all the dipterocarps, was tolerant under full solar exposure. Domestication farms should include or integrate fruit trees, vegetable trees (like bago or Gnetum gnemon) and other economic plants. Domestication trials of barit, anislag, sudiang, other dipterocarps, bago, nito, sig-id, rattan and other sources of raw materials for handicrafts should also be tried.

Plant Functional Traits and the Distribution of West African Rain Forest Trees along the Rainfall Gradient

Plant morphological and physiological traits affect the way plants tolerate environmental stresses and therefore play an important role in shaping species distribution patterns in relation to environmental gradients. Despite our growing knowledge on the role of functional traits in structuring plant communities, few studies have tested their importance at large scales in the wet tropics. Here, we describe the distribution patterns of the most important West African rain forest timber species along the regional rainfall gradient and relate them to their functional traits. We found that the distribution patterns of 25 out of the 31 studied species (80%) were significantly related to mean annual rainfall. Shade tolerance and drought resistance were identified as the main strategy axes of variation. Wood density and leaf deciduousness emerged as the best predictor traits of species position along the rainfall gradient, explaining respectively 32 and 15 percent of the variation. Species traits tended to show stronger relationships with estimated optimum annual rainfall for each species than to the extreme rainfall conditions where they occur. The significant role of rainfall in shaping timber species distribution and the strong relationships between species traits and rainfall indicate that changes in climate, especially declining rainfall, could have strong effects on species composition and abundance in these tropical forests.

Studies on raising and preparation of planting stock of three indigenous forest timber species in Nigeria

Seed germination studies, seedling growth, planting stock preparation and field trial at planting espacement of 3 m x 3 m were evaluated in the study. Soaking seeds in tap water for ten days with daily replacement of water yielded 100% seed germination for A. africana, 100% for A. boonei and 90% for A. lebbeck respectively in light condition. These values were better than those obtained in the control and dark condition. Growth values observed in forest topsoil were significantly different from those from river sand. From Forest Topsoil the total plant heights were 98 ± 16.33 cm for A. africana, 41 ± 6.83 cm for A. lebbeck and 70 ± 11.66 cm for A. boonei while from the river sand, A. Africana had 36 ± 6.0 cm, A. lebbeck had 26.3 ± 4.38 cm and A. boonei had 25.6 ± 4.27 cm. The field trial showed that there is prospect of successful domestication of these species using stumps or seedlings as planting stock. Significant difference was not observed in the trial. The only observed advantage is that more stumps can be transported than the seedlings. For quality planting stock production, soaking the seeds of the species under study for 10 days with daily replacement of water, forest topsoil as seedling growth medium, stumps and seedlings as planting stock are recommended. Keywords: Afzelia africana, Albizia lebbec, Alstonia boonei,Planting stock, agroforestryInternational Journal of Biological and Chemical Sciences Vol. 2 (4) 2008: pp. 573-578

The Possibility of Using Timber from Plantation Forest Treated with Plastic and CCB for Marine Construction

Recently, timber estate or plantation forest plays an important role on wooden based industries. However, the plantation timber quality is relatively low. Some treatments have been developed to improve its low quality, such as preservation with CCB (Chromate Copper Boron) and impregnation with plastic compounds. This study is to compare the durability of timber treated with plastic and CCB, non-treated from plantation forest timber as well as from natural forest. The plantation timber studied were jeungjing (Paraserianthes falcataria), damar (Agathis sp.), pinus (Pinus merkusii), and rubberwood (Hevea brasilliensis). Non-treated timbers that usually used for marine construction were ulin (Eusideroxylon zwageri), jati/teak (Tectona grandis), laban (Vitex pubescens) and merbau (Instia bijuga). After 6 and 12 months, the results showed that CCB preserved timber were more durable than plastic impregnated timber and non- treated timber. Wood samples were mostly attacked by marine borer organisms from the family of Pholadidae and Teredinidae. The experiment results revealed the possibility of using those plantation forest timber species for marine construction purposes.

Catastrophic disturbance, logging and the ecology of mahogany (Swietenia macrophylla King): grounds for listing a major tropical timber species in CITES

Recent debate on whether or not mahogany (Swietenia macrophylla King) is threatened by the international timber trade has focused on the breadth of its range and estimates of the remaining stock of mahogany trees. These data are inadequate to reveal the status of mahogany populations, both because they are incomplete in areal extent and because they do not reveal population parameters such as the existence or density of young trees smaller than commercial size. However, there is sufficient information on the regeneration ecology of mahogany to indicate that under natural conditions this species regenerates in essentially even-aged stands after catastrophic disturbances destroy many or most trees, and, in the case of fires and flooding, saplings and seedlings as well. Adult mahoganies tend to survive these events, and regenerate by shedding seed onto the resulting gaps or clearings. This ecological strategy makes mahogany vulnerable to logging, first because juvenile mahoganies are not found in the understorey, and secondly because logging operations shortcircuit mahogany regeneration processes by selectively removing almost all mahogany seed sources while leaving standing competing vegetation of other species. Listing of mahogany in CITES Appendix II could provide both a mechanism to fill in gaps in information and an incentive to change current practices in favour of silvicultural management to provide for regeneration of this valuable timber species in forests subjected to logging.

The Growth of Two Forest Tree Species Adjacent to a Periodic Source of Air Pollution

The effects of an isolated, periodically varied source of nitrogen oxides and sulfur dioxide air pollutants on the growth of two forest timber species was investigated. The annual production levels from 1941 through 1971 of the Radford Army Ammunition Plant (Arsensal), Radford, Virginia, were used as indicators of relative pollution emissions. The annual increment growth of 43 eastern white pine and 50 yellow poplar was determined to the nearest 0.05 mm with a dendrochronograph from 3.2 mm diam increment cores taken 1.37 m up from the base of each tree. An inverse relationship, significant at the 99.5% confidence level, was found by linear regression analyses to exist between the fluctuating production levels of the Arsenal and the annual increment growth of white pine and yellow poplar. Correlations significant at the 97.5% confidence level were found to exist between the annual increment growth of white pine and yellow poplar and the amount of seasonal and annual rainfall, respectively.