scholarly journals Effect of Disturbance Regimes on Spatial Patterns of Tree Species in Three Sites in a Tropical Evergreen Forest in Vietnam

2016 ◽  
Vol 2016 ◽  
pp. 1-16 ◽  
Author(s):  
Do Thi Ngoc Le ◽  
Nguyen Van Thinh ◽  
Nguyen The Dung ◽  
Ralph Mitlöhner
Keyword(s):  
Spatial Patterns ◽  
Tree Species ◽  
Interspecific Interactions ◽  
Abundant Species ◽  
Evergreen Forest ◽  
Small Scale ◽  
Forest Types ◽  
Disturbance Regimes ◽  
Tropical Evergreen Forest ◽  
Disturbed Forest

The effects of disturbance regimes on the spatial patterns of the five most abundant species were investigated in three sites in a tropical forest at Xuan Nha Nature Reserve, Vietnam. Three permanent one-ha plots were established in undisturbed forest (UDF), lightly disturbed forest (LDF), and highly disturbed forest (HDF). All trees ≥5 cm DBH were measured in twenty-five 20 m × 20 m subplots. A total of 57 tree species belonging to 26 families were identified in the three forest types. The UDF had the highest basal area (30 m2 ha−1), followed by the LDF (17 m2 ha−1) and the HDF (13.0 m2 ha−1). The UDF also had the highest tree density (751 individuals ha−1) while the HDF held the lowest (478 individuals ha−1). Across all species, there were 417 “juveniles,” 267 “subadults,” and 67 “adults” in the UDF, while 274 “juveniles,” 230 “subadults,” and 36 “adults” were recorded in the LDF. 238 “juveniles,” 227 “subadults,” and 13 “adults” were obtained in the HDF. The univariate and bivariate data with pair- and mark-correlation functions of intra- and interspecific interactions of the five most abundant species changed in the three forest types. Most species indicated clumping or regular distributions at small scale, but a high ratio of negative interspecific small-scale associations was recorded in both the LDF and HDF sites. These were, however, rare in the UDF.

Determinants of spatial patterns of canopy tree species in a tropical evergreen forest in Gabon

2019 ◽  
Vol 30 (5) ◽  
pp. 929-939 ◽  
Author(s):  
Nestor Laurier Engone Obiang ◽  
David Kenfack ◽  
Nicolas Picard ◽  
James A. Lutz ◽  
Pulchérie Bissiengou ◽  
...  
Keyword(s):  
Spatial Patterns ◽  
Tree Species ◽  
Evergreen Forest ◽  
Canopy Tree ◽  
Tropical Evergreen Forest ◽  
Canopy Tree Species

scholarly journals Phenology of Leaf Flushing, Flower Initiation and Fruit Maturation in Dry Deciduous and Evergreen Forests of Bhadra Wildlife Sanctuary, Karnataka, Southern India

Our Nature ◽  
1970 ◽  
Vol 9 (1) ◽  
pp. 89-99 ◽  
Author(s):  
A. Nanda ◽  
H.M. Prakasha ◽  
Y.L. Krishna Murthy ◽  
H.S. Suresh
Keyword(s):  
Tree Species ◽  
Dry Forest ◽  
Evergreen Forest ◽  
Flower Initiation ◽  
Forest Types ◽  
Fruit Maturation ◽  
Wildlife Sanctuary ◽  
Leaf Initiation ◽  
Evergreen Forests ◽  
Bhadra Wildlife Sanctuary

Varying with altitude and rainfall of two forest types of tropical forest were studied. Community wide pattern in both vegetative and reproductive phenophases among various tree species of Bhadra wildlife sanctuary, Karnataka is reported here. Leaf initiation peaks in the month of April in dry forest, after leaf less period of 1-2 months, in evergreen forest leaf initiation peaks in the month of January simultaneously with leaf senescence. Flower initiation begins from January till June with a peak in April in dry forest. Evergreen forest starts from November to march with a peak in January and February. Fruit maturation in dry forest starts from March to December with a peak in August and November, in evergreen forest from January to July with a peak in April.DOI: http://dx.doi.org/10.3126/on.v9i1.5738

scholarly journals Spider assemblages on tree trunks in primeval deciduous forests of the Białowieża National Park in eastern Poland

2018 ◽  
Vol 29 (2) ◽  
pp. 75-85
Author(s):  
Marzena Stańska ◽  
Tomasz Stański ◽  
Joanna Hawryluk
Keyword(s):  
Species Richness ◽  
Tree Species ◽  
National Park ◽  
Riparian Forest ◽  
Abundant Species ◽  
Deciduous Forests ◽  
Forest Types ◽  
Numerous Species ◽  
Białowieża National Park ◽  
Spider Abundance

We analysed spider assemblages of tree trunks in an oak-lime-hornbeam forest, an ash-alder riparian forest and an alder carr in the primeval stands of the Białowieża National Park. Spiders were collected from June 1998 to October 2000 using bark traps. A total of 2,182 spider individuals, belonging to 43 species and 14 families was collected. The forest types differed in the spider abundance and species richness. The differences probably resulted from different tree species and different environmental conditions in the forest types. The most numerous species in oak-lime-hornbeam forest and in alder carr was Amaurobius fenestralis, whereas Anyphaena accentuatawas the most abundant species in ash-alder riparian forest. Four species (Amaurobius fenestralis, Anyphaena accentuata, Segestria senoculataand Neriene montana) were collected in each month (March – October), whereas most species were recorded sporadically or in some periods.

Successional sequence of forest types in a disturbed dry forest reserve in southern Benin, West Africa

2001 ◽  
Vol 17 (4) ◽  
pp. 525-539 ◽  
Author(s):  
CHRISTIAN NANSEN ◽  
ATTI TCHABI ◽  
WILLIAM G. MEIKLE
Keyword(s):  
Tree Species ◽  
Hierarchical Classification ◽  
Dry Forest ◽  
Forest Types ◽  
Forest Patches ◽  
Forest Reserve ◽  
Tree Species Composition ◽  
Disturbed Forest ◽  
Lama Forest ◽  
Southern Benin

Human pressure on forest resources in southern Benin has led to a dramatic reduction and disturbance of natural forest patches. The largest remaining forest reserve in southern Benin is the Lama forest, which is known to be a reserve for many endangered species and situated in the boundary between dry forest and savanna. From cluster analysis and hierarchical classification of tree species composition, five forest types were identified in the Lama forest, and ordination techniques were used to determine to what extent these forest types were associated with physiognomic tree characteristics. The geographical position of vegetation plots was used to examine the spatial distribution of the identified forest types. The forest types were interpreted as levels in a successional sequence ranging from either disturbed forest or formerly cultivated farmland to dense forest. Based on the outlined succession sequence it was suggested that reforestation should focus on establishment of Anogeissus leiocarpus, Albizia zygia, Lannea nigritana, Ficus exasperata and Lonchocarpus sericeus as these tree species are associated with the initial forest types.

scholarly journals Spatial Patterns and Interspecific Associations During Natural Regeneration in Three Types of Secondary Forest in the Central Part of the Greater Khingan Mountains, Heilongjiang Province, China

Forests ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 152 ◽  
Author(s):  
Lingyu Zhang ◽  
Lingbo Dong ◽  
Qiang Liu ◽  
Zhaogang Liu
Keyword(s):  
Spatial Distribution ◽  
Spatial Patterns ◽  
Tree Species ◽  
Natural Regeneration ◽  
Random Distribution ◽  
Distribution Patterns ◽  
Forest Types ◽  
Development Stages ◽  
Interspecific Associations ◽  
Adult Trees

Seedling and sapling spatial patterns are important in community regeneration, and understanding the natural regeneration mechanisms of tree species in relation to spatial patterns will help improve forest management and community restoration efficiency. Based on data from three fixed plots established in birch forests (BF), coniferous and broadleaved mixed forests (CBMF) and coniferous mixed forests (CMF) in the central Greater Khingan Mountains in Heilongjiang Province, China, in 2017, we used the univariate and bivariate O-ring functions of the point pattern analysis method to evaluate the spatial patterns and associations of the main tree species in these three forest types at different development stages and identified the community successional stages according to the interspecific associations between dominant tree species and other tree species. The results showed that Betula platyphylla and Larix gmelinii in BF exhibited identical spatial distribution patterns and had a tendency to transition from an aggregated to a random distribution from saplings to adult trees, whereas every tree type in CBMF generally showed a random distribution. Adult trees of the main tree species in CMF, i.e., L. gmelinii and Picea koraiensis, mainly showed a random distribution, but P. koraiensis at other size classes generally showed an aggregated distribution. The intraspecific associations of the main tree species in BF and CMF at different development stages were constrained by the spatial scale within a given scope, while those in CBMF at different development stages were not significantly constrained by spatial scale. The results also show that the density of the three forest types was affected by the distance between the individuals of the various tree classes and adult trees, with different levels of influence. We analyzed the interspecific associations between dominant tree species and other tree species and then assessed community succession progress and found that the BF and CMF exhibited medium-term community succession, while the CBMF was in the primary stage. Our results further show that the spatial distribution patterns of the tree species in the small-diameter classes were jointly affected by adjacent habitats and diffusional limitations and that scale dependence existed in the intraspecific and interspecific associations. The analysis of the natural regeneration of spatial distribution and interspecific associations represents an efficient way to explore the stability of forest communities and dynamic changes in interspecific relationships during succession. The study results thus provide a theoretical basis for developing rational forest management measures.

Evaluation of ERTS Imagery for Vegetation Interpretation in British Columbia

1974 ◽  
Vol 28 (2) ◽  
pp. 147-154 ◽  
Author(s):  
E.T. Oswald
Keyword(s):  
British Columbia ◽  
Image Analysis ◽  
Natural Resources ◽  
Tree Species ◽  
Small Scale ◽  
Forest Types ◽  
Forest Land ◽  
Forest Stands ◽  
Vegetation Communities ◽  
Forested Areas

ERTS imagery has provided a means of surveying the natural resources on the earth’s surface by multiband, small-scale sequential imagery. This is a new tool for taking an inventory of natural resources. It requires evaluation for different purposes. The imagery was evaluated for distinguishing vegetation communities. Nonforested land could be easily separated from forest land and some distinctions could be made within these broad categories. Cut-over forest land, some meadows, grassland and highly developed urban land (towns) could be separated within the nonforested land. Differently aged forest stands, either from fire or reforestation, could be distinguished within the forested areas. Tree species could not be separated except through knowledge of successional patterns in some areas. Major forest types were generally not separable. The results and conclusions are tentative because equipment for image analysis was not available and only two sets of imagery of study areas were available: one in mid-May and one in mid-August.

scholarly journals The composition and diversity of natural regeneration of tree species in gaps under different intensities of forest disturbance

2021 ◽  
Author(s):  
Maame Esi Hammond ◽  
Radek Pokorný ◽  
Daniel Okae-Anti ◽  
Augustine Gyedu ◽  
Irene Otwuwa Obeng
Keyword(s):  
Tree Species ◽  
Natural Regeneration ◽  
Forest Disturbance ◽  
Forest Site ◽  
Gap Formation ◽  
Tree Species Composition ◽  
Forest Sites ◽  
Significant Difference ◽  
Shade Tolerant Species ◽  
Disturbed Forest

AbstractThe positive ecological interaction between gap formation and natural regeneration has been examined but little research has been carried out on the effects of gaps on natural regeneration in forests under different intensities of disturbance. This study evaluates the composition, diversity, regeneration density and abundance of natural regeneration of tree species in gaps in undisturbed, intermittently disturbed, and disturbed forest sites. Bia Tano Forest Reserve in Ghana was the study area and three gaps each were selected in the three forest site categories. Ten circular subsampling areas of 1 m2 were delineated at 2 m spacing along north, south, east, and west transects within individual gaps. Data on natural regeneration < 350 cm height were gathered. The results show that the intensity of disturbance was disproportional to gap size. Species diversity differed significantly between undisturbed and disturbed sites and, also between intermittently disturbed and disturbed sites for Simpson’s (1-D), Equitability (J), and Berger–Parker (B–P) indices. However, there was no significant difference among forest sites for Shannon diversity (H) and Margalef richness (MI) indices. Tree species composition on the sites differed. Regeneration density on the disturbed site was significantly higher than on the two other sites. Greater abundance and density of shade-dependent species on all sites identified them as opportunistic replacements of gap-dependent pioneers. Pioneer species giving way to shade tolerant species is a natural process, thus make them worst variant in gap regeneration.

scholarly journals Using a Groundwater Adjusted Water Balance Approach and Copulas to Evaluate Spatial Patterns and Dependence Structures in Remote Sensing Derived Evapotranspiration Products

2021 ◽  
Vol 13 (5) ◽  
pp. 853
Author(s):  
Mohsen Soltani ◽  
Julian Koch ◽  
Simon Stisen
Keyword(s):  
Remote Sensing ◽  
Water Balance ◽  
Spatial Pattern ◽  
Spatial Patterns ◽  
Principal Component ◽  
Small Scale ◽  
Dependence Structure ◽  
Test Case ◽  
Catchment Scale ◽  
Balance Approach

This study aims to improve the standard water balance evapotranspiration (WB ET) estimate, which is typically used as benchmark data for catchment-scale ET estimation, by accounting for net intercatchment groundwater flow in the ET calculation. Using the modified WB ET approach, we examine errors and shortcomings associated with the long-term annual mean (2002–2014) spatial patterns of three remote-sensing (RS) MODIS-based ET products from MODIS16, PML_V2, and TSEB algorithms at 1 km spatial resolution over Denmark, as a test case for small-scale, energy-limited regions. Our results indicate that the novel approach of adding groundwater net in water balance ET calculation results in a more trustworthy ET spatial pattern. This is especially relevant for smaller catchments where groundwater net can be a significant component of the catchment water balance. Nevertheless, large discrepancies are observed both amongst RS ET datasets and compared to modified water balance ET spatial pattern at the national scale; however, catchment-scale analysis highlights that difference in RS ET and WB ET decreases with increasing catchment size and that 90%, 87%, and 93% of all catchments have ∆ET < ±150 mm/year for MODIS16, PML_V2, and TSEB, respectively. In addition, Copula approach captures a nonlinear structure of the joint relationship with multiple densities amongst the RS/WB ET products, showing a complex dependence structure (correlation); however, among the three RS ET datasets, MODIS16 ET shows a closer spatial pattern to the modified WB ET, as identified by a principal component analysis also. This study will help improve the water balance approach by the addition of groundwater net in the ET estimation and contribute to better understand the true correlations amongst RS/WB ET products especially over energy-limited environments.

Sign in / Sign up

Export Citation Format

Share Document