THE PHYTOSOCIOLOGY OF THE DECIDUOUS FORESTS OF EXTREME SOUTHERN ONTARIO

1963 ◽  
Vol 41 (3) ◽  
pp. 379-438 ◽  
Author(s):  
Paul F. Maycock

A phytosociological analysis of the deciduous forest region of extreme southern Ontario is presented. One hundred and thirty-one stands were sampled quantitatively to determine the composition of the tree and sapling strata. A series of environmental characteristics were also measured or were carefully observed where measurement was impractical. The composition of the tree layer was expressed in terms of a series of importance values determined from measures of frequency, density, and dominance or basal area, on a relative basis, with the importance values for all trees in a stand summing to 300. An analysis of the relationship of the quantitative characteristics between all stands indicated the futility of the distinct association or distinct community approach to an understanding of forest ecological relationships in the region. An ordination of stands in relation to site moisture characteristics gave expression to the ecological tolerance of individual tree species and emphasized the continuous characteristics of forest patterns in the vegetational complex of the area.The forests of southern Ontario were related quantitatively to those of southern Wisconsin utilizing an index of regional influence based on overall importance for all tree species, in an attempt to interpret regional patterns within the Deciduous Forest Formation of North America.

2021 ◽  
Author(s):  
Talat Parveen ◽  
Orus Ilyas

Abstract The disturbance is a major factor driving the decline of tropical forests and their associated fauna. Henceforth, basic information on species diversity would be useful for assessing the success of management in the fragmented and human-disturbed landscape. We accounted for tree species diversity and their regeneration pattern from the tropical dry deciduous forest of Panna Tiger Reserve (PTR), India. Considering this, random vegetation sampling along with transects was carried out in different ranges of PTR. It is spread over in an area of 2998.98 km2 that situated in the northern part of Madhya Pradesh and distributed in Panna and Chhatarpur district. The tropical dry deciduous forest inventory in the 10.6132-ha area yielded a total of 46 woody species of > 10 cm GBH, belonged to 23 Families and 40 genera. The regeneration represented 27 species of < 30 cm height (seedling) under 16 families and 24 genera while sapling, which ranges from > 30cm to 1.3m, showed 24 species of 13 families and 32 genera. The Shannon diversity of Trees, seedlings, and saplings was 2.684, 2.525, and 2.401 respectively. A total stand density and basal area of 2391 stems of trees were estimated as 225.285 stand ha− 1 and 90.016 m2ha− 1 respectively. Tectona grandis scored the highest IVI value of 59.44 (19.81% of total IVI for all species) among the dominated tree species, followed by Acacia catechu (24.94), Abrus precatorius (23.25), Zizyphus xylopyra (22.94), Anogeissus latifolia (22.16) and Lagerstroemia parviflora (22.18). Nearly 23.913% of the total number of species was recorded as rare species. The highest seedling density was obtained for Diospyros melanoxylon followed by Zizyphus xylopyra, Aegle marmelos, Wrightia tintoria, and Tectona grandis, which declined in the subsequent sapling stage and showed a reverse pattern. Hence, the highest sapling density was recorded for Tectona grandis then Aegle marmelos, Wrightia tintoria, Diospyros melanoxylon, and Zizyphus xylopyra. A total of 36.956% of tree species were found to fail to establish in the community because species were represented by only adult or tree stage that listed as Not-regenerating. In terms of the most diverse family among the plant categories; viz. Tree, Seedling, Sapling, Fabaceae had the highest species richness. The highest tree stand density (127.576 stand ha− 1) was recorded in the girth class of 31-60cm (48.687% of the total tree stand density) followed by 10-30cm and 61-90cm. Likewise, a total basal area of 20.824 m2ha− 1 was occupied by 31-60cm that contributed 23.051% of the total basal area, so our data on the population structure of forest shows a similar trend wherein the distribution curve exponentially decreases with increasing girth classes that indicates not only a mid-successional forest but also a human-disturbed.


2019 ◽  
Vol 11 (18) ◽  
pp. 2078 ◽  
Author(s):  
Yuhong He ◽  
Jian Yang ◽  
John Caspersen ◽  
Trevor Jones

Recent advances in remote sensing technology provide sufficient spatial detail to achieve species-level classification over large vegetative ecosystems. In deciduous-dominated forests, however, as tree species diversity and forest structural diversity increase, the frequency of spectral overlap between species also increases and our ability to classify tree species significantly decreases. This study proposes an operational workflow of individual tree-based species classification for a temperate, mixed deciduous forest using three-seasonal WorldView images, involving three steps of individual tree crown (ITC) delineation, non-forest gap elimination, and object-based classification. The process of species classification started with ITC delineation using the spectral angle segmentation algorithm, followed by object-based random forest classifications. A total of 672 trees was located along three triangular transects for training and validation. For single-season images, the late-spring, mid-summer, and early-fall images achieve the overall accuracies of 0.46, 0.42, and 0.35, respectively. Combining the spectral information of the early-spring, mid-summer, and early-fall images increases the overall accuracy of classification to 0.79. However, further adding the late-fall image to separate deciduous and coniferous trees as an extra step was not successful. Compared to traditional four-band (Blue, Green, Red, Near-Infrared) images, the four additional bands of WorldView images (i.e., Coastal, Yellow, Red Edge, and Near-Infrared2) contribute to the species classification greatly (OA: 0.79 vs. 0.53). This study gains insights into the contribution of the additional spectral bands and multi-seasonal images to distinguishing species with seemingly high degrees of spectral overlap.


2007 ◽  
Vol 22 (3) ◽  
pp. 213-219 ◽  
Author(s):  
Hailemariam Temesgen ◽  
David W. Hann ◽  
Vincente J. Monleon

Abstract Selected tree height and diameter functions were evaluated for their predictive abilities for major tree species of southwest Oregon. Two sets of equations were evaluated. The first set included four base equations for estimating height as a function of individual tree diameter, and the remaining 16 equations enhanced the four base equations with alternative measures of stand density and relative position. The inclusion of the crown competition factor in larger trees (CCFL) and basal area (BA), which simultaneously indicates the relative position of a tree and stand density, into the base height–diameter equations increased the accuracy of prediction for all species. On the average, root mean square error values were reduced by 45 cm (15% improvement). On the basis of the residual plots and fit statistics, two equations are recommended for estimating tree heights for major tree species in southwest Oregon. The equation coefficients are documented for future use.


2021 ◽  
Author(s):  
Soumya Dasgupta ◽  
Tapajit Bhattacharya ◽  
Prafulla Bhamburkar ◽  
Rahul Kaul

Tropical forests are complex systems with heterogenous community assemblages often threatened under conservation conflicts. Herbivory and disturbances affect the diversity and species assemblages within forest patches having different disturbance regimes. We studied the change in plant community composition and structure under a disturbance gradient in the tropical dry deciduous forest of the corridor area between Nagzira-Navegaon Tiger reserve of central India. We tested the hypothesis that the plant community will change along the proximity gradient from the human settlement depending on the anthropogenic stress. We sampled 183 nested quadrat plots to collect data on species abundance and various disturbance parameters. Density, diversity, and Importance Value Index were calculated from the collected data on species abundance and girth at breast height (GBH) of individual tree species. We did multivariate analysis to assess the changes in species assemblage along the disturbance gradients. We found 76% dissimilarity between the plant communities in the three disturbance gradients from near to far from the villages perpetrated by the difference in mean abundance of species like Tectona grandis, Terminalia sp, and Largerstroemia parviflora. The anthropogenic factors significantly influence the density and diversity of tree species and regeneration classes. We found the abundance of regeneration class increased along the distance from the villages. The study intensifies the need for proper management and conservative approach to preserve the minimum diversity of the forest patches for its structural and functional contiguity as a corridor in the central India's highly susceptible and intricate corridor framework.


2007 ◽  
Vol 37 (8) ◽  
pp. 1438-1449 ◽  
Author(s):  
Robert E. Froese ◽  
Andrew P. Robinson

We subjected the individual-tree, aspatial basal area increment model developed for the Inland Empire Variant of the Forest Vegetation Simulator to validation and evaluation tests. We used a large set of independent data from the Forest Inventory and Analysis program that covers the geographic extent to which the model is usually applied. Equivalence tests did not validate the model as a predictive tool using nominated criteria, though they usually did validate the model structure as a theory. Design-unbiased estimates of prediction error suggest that the model overpredicts diameter and volume increment by 14% and 2%, respectively. Relationships between species, bias, and predictor variables suggest the model may overpredict most on productive sites. We spatially interpolated the model performance across the study area using thin-plate splines. The observed regional patterns are examined using a selection of cross-sectional transects, and reveal a complex relationship between bias and the way climate effects are incorporated in the model structure that involve differences between the fitting and testing data. The model structure is surprisingly robust, but the representation of climate effects should be a priority in future revisions.


2020 ◽  
Vol 7 (3) ◽  
pp. 1029-1138
Author(s):  
Dharmendra Dugaya ◽  
PV Kiran ◽  
Rajnish Kumar Singh ◽  
Manmeet Kaur ◽  
Pradeep Chaudhry

We analyzed phytosociological characteristics of a tropical dry deciduous forest located in an urban environment of Indian Institute of Forest Management (IIFM) Campus in the capital city of Bhopal of Madhya Pradesh state, Central India. A Comparison has been made among the tree community characteristics during the years 1988, 2002 and 2020 in terms of tree species composition, stem density, basal area and Importance Value Index (IVI). At the time of establishment of the institute in 1988, the forest area resembleda degraded dry scrubland. Due to continuous care/protection, plantation activities, degraded forest recovered remarkably, ecological processes evolved favorably with canopy cover reaching over 60% in some patches and about 50% in general over most part of the campus. During last two decades, tree density increased from 319 to 525 stem ha-1 indicating an increase of 64% whereas basal area increased from 18470.79 cm2 ha-1 to 29782.31 cm2 ha-1,an increase of about 61%. Leguminaceae family represented 26.4% of the tree community followed by Combretaceae (11.76%). Shannon-Weiner index (1.31), Simpson index (0.93) and evenness index (0.85) are within the reported ranges for similar forest type of dry deciduous nature in India. Theresults of the presentstudy will help forest managers in conservation planning of urban tropical forest ecosystem of central India.


1970 ◽  
Vol 2 (3) ◽  
pp. 23-28 ◽  
Author(s):  
Ripu M Kunwar ◽  
Shiv P Sharma

Two community forests, Amaldapani and Juphal from Dolpa district, were selected for a study of quantitative analysis of tree flora. A total of 419 individual trees representing 16 species, 16 genera and 11 families were recorded. Total stand density and basal area were, respectively, 2100 trees ha-1 and 90 m2ha-1 in Amaldapani and 2090 tree ha-1 and 152 m2ha-1 in Juphal. Of the families, the Pinaceae was the most diverse, with 28 individuals representing five species and five genera, followed by the Rosaceae with three individuals representing two species and two genera. Pinus wallichiana, Abies spectabilis, Quercus semecarpifolia and Cedrus deodara had the highest importance value index and could therefore be considered the dominant species. Since the study area was diverse in tree population of conifers and deciduous forest tree species, it is essential to carry out further studies in order to establish conservation measures that will enhance local biodiversity. Key words: Vegetation, tree species, Pinus wallichiana, community forest, Dolpa Himalayan Journal of Sciences 2(3): 23-28, 2004


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.


2011 ◽  
Vol 87 (04) ◽  
pp. 542-551 ◽  
Author(s):  
Arthur Groot ◽  
Robert Schneider

Forest resource inventories must include wood quality information to support the optimum use of wood fibre. The objective of this study was to develop models relating maximum live branch diameter (MBD), which affects lumber value, to tree and stand characteristics that can be measured through current and emerging remote sensing technologies. Using non-linear mixed effects models for six Canadian conifer species, as well as for three broad-leaved species, MBD was related to crown radius, tree height, crown length, stand basal area, and basal area of trees larger than the subject tree. Models that included only individual tree characteristics (crown radius, tree height, and crown length) did not perform as well as models that additionally included stand characteristics (stand basal area and basal area of larger trees). Models that took into account tree species performed better than models that did not; in particular, broadleaved species had much thicker branches than conifers. The best model did not show bias with respect to independent variables and had root mean square error of 0.32 cm. For the best model, prediction error was not related to silvicultural treatment. These model characteristics strongly support the potential to successfully predict MBD from remotely sensed data.


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