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

2017 ◽  
Vol 390 ◽  
pp. 104-118 ◽  
Author(s):  
Ruslandi ◽  
W.P. Cropper ◽  
F.E. Putz
2012 ◽  
Vol 52 (No. 4) ◽  
pp. 181-187 ◽  
Author(s):  
F. Hájek

This paper describes the automated classification of tree species composition from Ikonos 4-meter imagery using an object-oriented approach. The image was acquired over a man-planted forest area with the proportion of various forest types (conifers, broadleaved, mixed) in the Krušné hory Mts., Czech Republic. In order to enlarge the class signature space, additional channels were calculated by low-pass filtering, IHS transformation and Haralick texture measures. Employing these layers, image segmentation and classification were conducted on several levels to create a hierarchical image object network. The higher level separated the image into smaller parts regarding the stand maturity and structure, the lower (detailed) level assigned individual tree clusters into classes for the main forest species. The classification accuracy was assessed by comparing the automated technique with the field inventory using Kappa coefficient. The study aimed to create a rule-base transferable to other datasets. Moreover, the appropriate scale of common image data and utilisation in forestry management are evaluated.


2014 ◽  
Vol 3 (1) ◽  
pp. 10 ◽  
Author(s):  
Humphrey Igbinosa Aigbe ◽  
Godwin Ejakhe Omokhua

Tree species composition and diversity were assessed in Oban Forest Reserve. Three stage sampling procedure was used to collect data on tree parameters – diameter at breast height (dbh); diameters over bark at the base, middle and top; merchantable height and total height using a minimum dbh limit of ≥10 cm in the tertiary sample plots. A total of 808 trees were measured and 72 species identified in the study area. Stand level parameters were estimated and tree diversity assessed. Results indicate that an average number of stems encountered per hectare were 306. Population densities of individual tree species ranged from 1 to 22 ha-1. Population densities of species were poor. The basal area/ha estimated is 34.67m2 and the species richness index obtained was 10.605, which indicate high species richness. The value of Shannon’s Index (HI) is 3.795 which is quite high.The results show that the forest reserve is a well-stocked tropical rainforest in Nigeria. The relative richness of the forest reserve in terms of individual tree species does not correlate well with the abundance because the abundance of each of the species was quite low and density poor. While there is paucity of most species, Staudtia stipitata was the most abundant (22 tree/ha). The forest has reverted back to the turbulent agrading stage of the forest growth cycle. 


Author(s):  
Md. Humayain Kabir ◽  
Hillol Barua

Riparian vegetation has been depleting in the many river basins of Bangladesh. Consequently, this study assessed the tree species composition, structure and diversity of the midstream area of the Halda River in Bangladesh. Twenty two quadrats (20 × 20m in size) were sampled. A total of 414 individual tree stems of ≥10 cm DBH of 36 tree species belonging to 31 genera and 15 families were enumerated. Density, Basal area and volume of the tree species were measured. Different diversity indices, i.e. Shannon-Wienners Diversity Index, Simpson's Dominance Index, Pielou’s Species Evenness Index, Margalef's and Menhinick’s richness index were calculated. Fabaceae was the most represented family with nine species, followed by Moraceae, Meliaceae and Anacardiaceae. Density, basal area and volume of the trees were 470.45 stem/ha, 19.09m²/ha and 139.42m³/ha, respectively. Samanea saman was found to be dominant, showing a maximum IVI, followed by v, Mangifer aindica, Eucalyptus camaldulensis and Artocarpus heterophyllus. The findings of the study will be helpful for the posterior researchers in their research work and their future tree based planning programs and conservation. So it is recommended that greater emphasis should be taken to proper management and conservation against over extraction and illegal felling for the maintenance of existing tree species composition and density.


2008 ◽  
Vol 159 (4) ◽  
pp. 80-90 ◽  
Author(s):  
Bogdan Brzeziecki ◽  
Feliks Eugeniusz Bernadzki

The results of a long-term study on the natural forest dynamics of two forest communities on one sample plot within the Białowieża National Park in Poland are presented. The two investigated forest communities consist of the Pino-Quercetum and the Tilio-Carpinetum type with the major tree species Pinus sylvestris, Picea abies, Betula sp., Quercus robur, Tilia cordata and Carpinus betulus. The results reveal strong temporal dynamics of both forest communities since 1936 in terms of tree species composition and of general stand structure. The four major tree species Scots pine, birch, English oak and Norway spruce, which were dominant until 1936, have gradually been replaced by lime and hornbeam. At the same time, the analysis of structural parameters indicates a strong trend towards a homogenization of the vertical stand structure. Possible causes for these dynamics may be changes in sylviculture, climate change and atmospheric deposition. Based on the altered tree species composition it can be concluded that a simple ≪copying≫ (mimicking) of the processes taking place in natural forests may not guarantee the conservation of the multifunctional character of the respective forests.


2017 ◽  
Vol 47 (8) ◽  
pp. 997-1009 ◽  
Author(s):  
Katherine F. Crowley ◽  
Gary M. Lovett

As tree species composition in forests of the northeastern United States changes due to invasive forest pests, climate change, or other stressors, the extent to which forests will retain or release N from atmospheric deposition remains uncertain. We used a species-specific, dynamic forest ecosystem model (Spe-CN) to investigate how nitrate (NO3–) leaching may vary among stands dominated by different species, receiving varied atmospheric N inputs, or undergoing species change due to an invasive forest pest (emerald ash borer; EAB). In model simulations, NO3– leaching varied widely among stands dominated by 12 northeastern North American tree species. Nitrate leaching increased with N deposition or forest age, generally with greater magnitude for deciduous (except red oak) than coniferous species. Species with lowest baseline leaching rates (e.g., red spruce, eastern hemlock, red oak) showed threshold responses to N deposition. EAB effects on leaching depended on the species replacing white ash: after 100 years, predicted leaching increased 73% if sugar maple replaced ash but decreased 55% if red oak replaced ash. This analysis suggests that the effects of tree species change on NO3– leaching over time may be large and variable and should be incorporated into predictions of effects of N deposition on leaching from forested landscapes.


2006 ◽  
Vol 2 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Yong Kwon Lee ◽  
Don Koo Lee ◽  
Su‐Young Woo ◽  
Emmanuel Rodantes G. Abraham ◽  
Wilfredo M. Carandang ◽  
...  

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