Articles containing the keyword 'tropical'

The impact of carbon sequestration on the financial profitability of four tree plantation cases in Finland and the Philippines were examined. On the basis of stem wood growth; the accumulation of carbon in forest biomass, the formation and decomposition of litter, and the carbon flow in wood-based products were assessed for each reforestation case representing boreal (Finland) and moist tropical conditions (the Philippines). Using different unit values for carbon sequestration the profitability of reforestation was estimated for a fixed 100-year period on a per hectare basis. The financial profitability of reforestation increased notably when the sequestered carbon had high positive values. For example, when the value of carbon sequestration was set to be Twenty-five United States Dollar per megagram of carbon (25 USO/Mg C), the internal rate of return (IRR) of a reforestation investment with Norway spruce (Picea abies (L.) H. Karst.) in Finland increased from 3.2% to 4.1 %. Equally, the IRR of reforestation with mahogany (Swietenia macrophylla King) in the Philippines increased from 12.8% to 15.5%. The present value of carbon sequestration ranged from 39–48% and from 77–101% of the present value of the reforestation cost in Finland and the Philippines, respectively when a 25 USO/Mg C shadow price and a 5% discount rate were applied. Sequestration of one mg of carbon in reforestation in Finland and the Philippines was estimated to cost from 10.5–20.0 and from 4.0–13.6 USO, respectively.

• Niskanen, E-mail: an@mm.unknown
• Rantala, E-mail: tr@mm.unknown
• Saastamoinen, E-mail: os@mm.unknown

The area of world forests is gradually declining because of various human activities, such as shifting cultivation, uncontrolled logging and industrial pollution. Continuation of the trends would have detrimental ecological, economic and social effects on global scale. The diversity of the problem is wide. The situation in the tropical developing countries differs from that in the industrialized world. With the present rates of population growth and unchanged forest policies, the fuelwood shortage in developing countries is rapidly aggravating. The need for more agricultural land tends to prejudice conscious efforts to increase wood production.

The industrialized countries are experiencing problems in introducing forest policy means to maintain sufficient timber supply. Rapidly increasing pollution problem cause a serious hazard to the existence of the whole forest ecosystem. Forestry has primarily been a national issue of relatively low priority in political decision-making, which has resulted in insufficient action to remedy the situation at national and international level.

The renewability of forest resources represents a strategic asset, the importance of which is bound to increase in the long-run potential for badly needed economic and social change in the world’s poor rural areas will be lost.

The PDF includes a summary in Finnish.

• Simula, E-mail: ms@mm.unknown

The article presents forests on Tehri Garhwal district (former kingdom, now part of India). Most of the area is middle-mountainous area with valleys and hills. The forests in the area belong to three different forest zones: tropical, temperate and alpine. The article presents the characteristics of the forests and vegetation for every zone. 

The volume 34 of Acta Forestalia Fennica is a jubileum publication of professor Aimo Kaarlo Cajander.

• Heske, E-mail: fh@mm.unknown

Despite the influence of cavities on the survival and distribution of cavity-dependent fauna, the variation in the density and characteristics of tree cavities across different habitat types in tropical forests is unknown. In this study, we surveyed 26 312 living trees from 376 species and compared cavity density and characteristics (height, size, type, and orientation) across five habitat types (valley, low-slope, high-slope, high-gully, and high-plateau) in a 20-hectare tropical rainforest in southwest China. From a total of 2047 cavities, we found that cavity density was mainly driven by habitat rather than tree species richness or diameter at breast height (DBH), and the characteristics of cavities were not uniformly distributed across habitats. Cavities were significantly more abundant in high- and low-slope than high-plateau habitats. Compared with other habitats, more “butt hollow” cavity types were found in high-slope habitat and they occurred at a lower tree height, whereas more “crack” cavities were found in low-slope habitat and they had a narrower entrance diameter. Although the mean orientation of cavities faced towards the northeast, cavity orientation varied significantly across habitat types. Our results indicate that certain types of cavities are concentrated in specific habitat types, which can provide avenues for forest management and biodiversity conservation. We highlight the importance of habitat heterogeneity in providing resources for cavity nesters.

• Liu, Key Laboratory of Southwest China Wildlife Resources Conservation of Ministry of Education, Key Laboratory of Environmental Science and Biodiversity Conservation (Sichuan Province) and Institute of Plant Adaptation and Utilization in Southwest Mountains, China West Normal University, Nanchong, Sichuan 637009, China; Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China E-mail: liujunyan2300@163.com
• Tang, Key Laboratory of Southwest China Wildlife Resources Conservation of Ministry of Education, Key Laboratory of Environmental Science and Biodiversity Conservation (Sichuan Province) and Institute of Plant Adaptation and Utilization in Southwest Mountains, China West Normal University, Nanchong, Sichuan 637009, China E-mail: jft@nn.ch
• Chen, Royal Botanic Gardens, Kew, Wakehurst Place, West Sussex RH17 6TN, UK; Mitrani Department of Desert Ecology, Swiss Institute for Dryland Environmental and Energy Research, Jacob Blaustein Institutes for Desert Research, Ben-Gurion University of the Negev, Midreshet Ben-Gurion, Beer-Sheva 8499000, Israel E-mail: chensichong0528@gmail.com
• Ma, Ecological Restoration and Conservation of Forests and Wetlands Key Laboratory of Sichuan Province, Sichuan Academy of Forestry, Chengdu 610081, China E-mail: mawenbao_2000@126.com
• Zheng, Key Laboratory of Tropical Forest Ecology, Xishuangbanna Tropical Botanical Garden, Chinese Academy of Sciences, Mengla, Yunnan 666303, China E-mail: dioeco@outlook.com
• Dong, Key Laboratory of Southwest China Wildlife Resources Conservation of Ministry of Education, Key Laboratory of Environmental Science and Biodiversity Conservation (Sichuan Province) and Institute of Plant Adaptation and Utilization in Southwest Mountains, China West Normal University, Nanchong, Sichuan 637009, China E-mail: dongtf@aliyun.com

Detecting and monitoring forest disturbance from selective logging is necessary to develop effective strategies and polices that conserve tropical forests and mitigate climate change. We assessed the potential of using the remote sensing tool, CLASlite forest monitoring system, to detect disturbance from timber harvesting in four community forests (ejidos) of the Selva Maya on the Yucatan Peninsula, Mexico. Selective logging impacts (e.g. felling gaps, skid trails, logging roads and log landings) were mapped using GPS in the 2014 annual cutting areas (ACAs) of each ejido. We processed and analyzed two pre-harvest Landsat images (2001 and 2013) and one post-harvest image (November 2014) with the CLASlite system, producing maps of degraded, deforested and unlogged areas in each ACA. Based on reference points of disturbed (felling and skidding), deforested (log landings and roads) and unlogged areas in each ACA, we applied accuracy assessments which showed very low overall accuracies (<19.1%). Selective logging impacts, mainly from log landings and new logging road construction, were detected in only one ejido which had the highest logging intensity (7 m³ ha^–1).

• Hernández-Gómez, Facultad de Ciencias Agrícolas, Universidad Veracruzana. Circuito Gonzalo Aguirre Beltrán, Isleta, Xalapa, Veracruz. C.P. 91000, Mexico E-mail: urielxal@gmail.com
• Cerdán, Facultad de Ciencias Agrícolas, Universidad Veracruzana. Circuito Gonzalo Aguirre Beltrán, Isleta, Xalapa, Veracruz. C.P. 91000, Mexico E-mail: ccerdan@uv.mx
• Navarro-Martínez, El Colegio de la Frontera Sur Av. Centenario km 5.5, Col. Pacto Obrero Campesino s/n. Chetumal, Quintana Roo. C.P. 77014, Mexico E-mail: manavaster@gmail.com
• Vázquez-Luna, Facultad de Ingeniería en Sistemas de Producción Agropecuaria, Universidad Veracruzana. Carretera Costera del Golfo Km. 220, C. Agrícola y Ganadera Michapan, Acayucan, Veracruz. C.P. 96000, Mexico E-mail: divazquez@uv.mx
• Armenta-Montero, Centro de Investigaciones Tropicales (CITRO), Universidad Veracruzana. Morelos No. 44 y 46, Zona Centro, Xalapa, Veracruz. C.P. 91000, Mexico E-mail: samaria.am@gmail.com
• Ellis, Centro de Investigaciones Tropicales (CITRO), Universidad Veracruzana. Morelos No. 44 y 46, Zona Centro, Xalapa, Veracruz. C.P. 91000, Mexico E-mail: eellis@uv.mx

Species-specific allometric equations for shrubs and small trees are relatively scarce, thus limiting the precise quantification of aboveground biomass (AGB) in both shrubby vegetation and forests. Fourteen shrub and small tree species in Eastern China were selected to develop species-specific and multispecies allometric biomass equations. Biometric variables, including the diameter of the longest stem (D), height (H), wet basic density (BD), and crown area and shape were measured for each individual plant. We measured the AGB through a non-destructive method, and validated these measurements using the dry mass of the sampled plant components. The AGB was related to biometric variables using regression analysis. The species-specific allometric models, with D and H as predictors (D-H models) accounted for 70% to 99% of the variation in the AGB of shrubs and small trees. A multispecies allometric D-H model accounted for 71% of the variation in the AGB. Although BD, as an additional predictor, improved the fit of most models, the D-H models were adequate for predicting the AGB for shrubs and small trees in subtropical China without BD data.

• Ali, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Tiantong National Forest Ecosystem Observations and Research Station, Ningbo 315114, Zhejiang, China; Department of Environmental Sciences, Abdul Wali Khan University Mardan, 23200, KPK, Pakistan E-mail: arshadforester@gmail.com
• Xu, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Tiantong National Forest Ecosystem Observations and Research Station, Ningbo 315114, Zhejiang, China E-mail: yumsh09@lzu.edu.cn
• Zhao, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Tiantong National Forest Ecosystem Observations and Research Station, Ningbo 315114, Zhejiang, China E-mail: zhaoyantao1991@163.com
• Zhang, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Tiantong National Forest Ecosystem Observations and Research Station, Ningbo 315114, Zhejiang, China E-mail: qingzq@yeah.net
• Zhou, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Tiantong National Forest Ecosystem Observations and Research Station, Ningbo 315114, Zhejiang, China E-mail: 792920738@qq.com
• Yang, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Tiantong National Forest Ecosystem Observations and Research Station, Ningbo 315114, Zhejiang, China E-mail: xjyangxd@sina.com
• Yan, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Tiantong National Forest Ecosystem Observations and Research Station, Ningbo 315114, Zhejiang, China E-mail: eryan@des.ecnu.edu.cn