scholarly journals Abundance status of flora in Mananga-Kotkot-Lusaran Watersheds, Cebu, Philippines

2006 ◽  
pp. 53-75 ◽  
Author(s):  
Justino Quimio

The paper describes the abundance status of forests and their species composition in the Mananga-Kotkot-Lusaran Watershed of Metro Cebu, Philippines. Data collection and analysis were undertaken according to the Braun-Blanquet (1964) methodology. Six vegetation types, such as grassland, brushland, pioneer vegetation, young plantation, 60-year old tanguile (Shorea polysperina) plantation and old-growth forest finest were sampled in 69 plots. The range of occurrence of species in sampled vegetation types is discussed. The study had recorded 414 species, in 249 genera and 103 families. They included 47 species of large trees, 71 medium trees, 118 small trees, 2 straggler figs, 7 shrubs, 2 palms, 74 erect herbaceous plants, 21 woody lianas, 32 grasses, 22 ferns and 1 moss. Aerial plants were not included in the inventory. Seven patches of natural growth remained extant in the watersheds but only one, the 40-hectare Tabunan forest patch, was big enough to have interior type forest. The other patches were only about 8 hectares or much less degraded in structure, poor in species, covered by climbing plants and pioneer trees and located either in rocky sleep slope or in cliff.

Botany ◽  
2010 ◽  
Vol 88 (4) ◽  
pp. 297-314 ◽  
Author(s):  
L. K. Baldwin ◽  
G. E. Bradfield

The resilience (measured as changes in functional group representation and species composition) of bryophyte communities found in the younger-aged (“matrix”) forests surrounding old-growth remnants was examined in two different forest types, warmer, drier (Nimpkish) versus cooler, wetter (Sayward), on Vancouver Island, British Columbia. Bryophytes were sampled within 10 m × 2 m belt transects (species composition only) and using 10 cm × 30 cm microplots (composition and abundance) in two age classes of matrix forest, clearcuts (age 7–20 years), and second-growth (age 25–49 years) as well as in remnant old-growth forest stands (age >300 years). The cover of all bryophytes was diminished and more patchily distributed in younger-aged stands; however, the richness and frequency of bryophyte functional groups showed different responses in the two younger age class forests. Disturbance-associated species exhibited both higher richness and frequency in clearcut plots and higher richness in second-growth plots. In comparison, the richness of species associated with old-growth was largely unchanged in younger-aged forests compared with old-growth forests; however, the frequency of occurrence of species associated with old-growth was significantly reduced in younger-aged forests. The cooler, wetter forests exhibited greater resilience, as the difference in species composition between second-growth and old-growth stands was less than that between second-growth and old-growth stands in the warmer, drier forests. The greater difference in second-growth species composition in the warmer, drier forests was attributed mainly to the persistence of disturbance-associated species.


2011 ◽  
Vol 37 (3) ◽  
pp. 230-238 ◽  
Author(s):  
J.R. Arévalo ◽  
L. de Nascimento ◽  
S. Fernández-Lugo ◽  
J. Mata ◽  
L. Bermejo

Zoosymposia ◽  
2011 ◽  
Vol 5 (1) ◽  
pp. 143-146 ◽  
Author(s):  
KIMIO HIRABAYASHI ◽  
GORO KIMURA ◽  
EISO INOUE

The species composition and abundance of adult caddisflies attracted to the illuminated showcase of a vending machine set along the middle reaches of the Shinano River were investigated every Sunday night from April to November in 2005 to 2007. A total of 1,405 adult caddisflies was collected during the investigation periods. We identified a total of 13 species belonging to 11 genera of 8 families. The most abundant species was Psychomyia acutipennis (Ulmer 1908) each year. Psychomyia acutipennis adults were collected from mid-May to the beginning of October (the range of mean air temperature was 13.8 to 27.7°C), with its seasonal abundance divided into several peaks, i.e., the end of May, the beginning of June, and the end of August to the beginning of September in both 2006 and 2007. On the other hand, in 2005 when there was no large-scale summer flood and there were no marked abundance peaks. The present study suggests that the mean air temperature and summer floods impacted the seasonal abundance of P. acutipennis adults.


2013 ◽  
Vol 6 (3) ◽  
pp. 178-183 ◽  
Author(s):  
Nubia França da Silva Giehl ◽  
Marco Bruno Xavier Valadão ◽  
Leandro Schlemmer Brasil ◽  
Josias Oliveira dos Santos ◽  
Sara Miranda Almeida ◽  
...  

Os efeitos de queimadas induzidas sobre a comunidade de abelhas Euglossini (Hymenoptera: Apidae) foram avaliados em floresta de transição entre o Cerrado e a Floresta Amazônica, no leste do Estado de Mato Grosso, Brasil. A riqueza, abundância e a composição de Euglossini foram determinadas em uma área controle não queimada (preservada), uma área queimada anualmente desde 2004 (degradação intermediária) e uma área queimada trienalmente desde 2004 (degradação elevada). Testamos a hipótese de que áreas com diferentes frequências de queimadas apresentam menor abundância de machos, menor riqueza e diferente composição de espécies de Euglossini em relação à área controle. As técnicas de coleta ativa e passiva de abelhas foram aplicadas usando seis substâncias puras para atração dos machos: β-ionona, benzoato de benzila, geraniol, fenil-etil-acetato, salicilato de metila e vanilina. Sete espécies foram catalogadas e não houve diferença nas abundâncias entre as três áreas amostradas (F (2, 12) = 0,150; p= 0,8). A riqueza estimada de espécies na área controle foi superior à área com fogo trienal (12 ± 3,8; 4 ± 2, respectivamente), enquanto a área com fogo anual apresentou riqueza intermediária (8 ± 4,35) e superior àquela da área com fogo trienal. A análise de UPGMA revelou diferença significativa quanto a composição de espécies da área de fogo trienal para as outras duas áreas. As queimadas anual e trienal reduziram a riqueza de espécies e alteraram a composição de espécies, com efeitos mais evidentes na área com fogo trienal, causando efeitos deletérios sobre a comunidade das abelhas das orquídeas. The effect of Fire on the Community of Euglossini (Hymenoptera: Apidae) in a Cerrado-Amazon Transitional Forest (Mato Grosso, Brazil) Abstract. We evaluated the effects of induced burned on Euglossini bee assemblages (Hymenoptera: Apidae) in a transitional area between Cerrado and Amazonia, eastern Mato Grosso, Brazil. We determinate abundances, richness and composition of Euglossini in three plots: control plot (unburned), plot burned each year since 2004 (intermediate degradation), plot burned each three years since 2004 (high degradation). We tested the hypothesis that two burned plots present lower male abundances, less species richness and different species composition in comparison with the control plot. We collected male bees actively and passively by using six pure fragrances: β-ionona, benzoato de benzila, geraniol, fenil-etil-acetato, salicilato de metila e vanilina. We collected seven species with no differences in male abundances among three plots (F (2, 12)= 0.150; p= 0.8). Estimated richness species in control the plot was higher than the plot burned each three years (12 ± 3.8; 4± 2, respectively), while plot burned each year showed intermediate richness (8 ± 4.35) and higher than plot burned each three years. Cluster Analysis (UPGMA) revealed significant differences in species composition of the triennial fire area to the other two areas. Our results suggest that fire occurring with different frequencies in transitional forest promote decreases in richness of species and modifications in species composition. These modifications were clearer in plot more degraded (burned each three years) and induce deleterious effects on orchid bee assemblage.


1983 ◽  
Vol 7 (4) ◽  
pp. 208-212 ◽  
Author(s):  
Robert N. Muller

Abstract An old-growth forest and a 35-year-old, second-growth forest on the Cumberland Plateau were studied to compare species composition and structure. Species composition and total basal area of the two stands did not differ, although total stand density was 19 percent lower and basal area of commercial species was 25 percent higher in the old-growth than in the second-growth stand. Analysis of size-class distributions showed that both stands were best represented by an inverse J-shaped distribution, which best describes old-age stands. The rapid regeneration of the second-growth stand seems to be the result of minimal disturbance to accumulated nutrient pools in the soil. The importance of these accumulated nutrient pools and implications for forest management on the Cumberland Plateau are discussed.


1992 ◽  
Vol 16 ◽  
pp. 220-224
Author(s):  
S.I. Severskiy ◽  
I.V. Severskiy

Methods of quantitative evaluation of the influence of local factors such as slope exposure (aspect and gradient) and types of vegetation on the distribution of snow cover found in the northern Tien Shan are described. This investigation is based on regular measurements of snow depth and density at different altitudes and exposures, and with different vegetation types. A strong statistical relationship was obtained between snow cover on the one hand and slope exposure and vegetation types on the other. Local factors have a stronger influence on the distribution of snow cover than elevation. These methods were used for the estimation of the distribution of snow cover in a typical river basin. The results obtained differ significantly from the results of evaluations made by traditional methods.


2015 ◽  
Vol 45 (9) ◽  
pp. 1215-1224 ◽  
Author(s):  
Per-Ola Hedwall ◽  
Grzegorz Mikusiński

Protected forest areas (PFAs) are key features of biodiversity conservation, and knowledge about long-term development is crucial in evaluating their efficiency and management needs. Longitudinal data on forest structure in PFAs is uncommon and often from small areas. Here we use data from the Swedish National Forest Inventory to study changes in more than 750 000 ha of PFAs over 60 years. Structures important for biodiversity, e.g., number of large trees and the volume of hard deadwood, including both standing and down wood, have more than doubled. The initial volume of deadwood, however, was very low. The overall tree species composition was stable over time, and only among the largest trees were there indications of a shift towards the late successional Norway spruce (Picea abies (L.) Karst.). Deadwood increased independent of species, size of wood, and site characteristics. This increase was positively related to the volume of living trees and forest age. We conclude that Swedish PFAs, in the absence of active management and under fire suppression at the landscape scale, develop structural components that are crucial for conservation of biodiversity. However, although tree species composition appears stable, present disturbance regimes in the PFAs are considerably different from those in naturally dynamic forests, which may have implications for long-term biodiversity maintenance.


2009 ◽  
Vol 57 (7) ◽  
pp. 556 ◽  
Author(s):  
Anneka V. Ferguson ◽  
Emma J. Pharo ◽  
Jamie B. Kirkpatrick ◽  
Jon B. Marsden-Smedley

Little is known of the interactive effects of fire and grazing on cryptogam species and assemblages. These effects were observed for bryophyte and lichen species in Tasmanian tussock grassland and hummock sedgeland several months after experimental burning and fencing. A factorial design was used on 40 randomly located and treated pairs of 1 m × 1 m quadrats in each of the vegetation types. In total, 24 cryptogam taxa were found, with grassland having a greater taxon richness, as well as higher total cryptogam cover and a different species composition, to the hummock sedgeland. There was greater cryptogam cover in the burned quadrats than the unburned quadrats in the grassland. However, only bryophytes had different species composition between burned and unburned quadrats. There was a small but significant difference in richness in hummock sedgeland, with burned being richer than unburned. Three species were more abundant in the burned than in the unburned treatments in the grassland, whereas no species responded to treatment in the sedgeland and no species responded to grazing. The fact that no species or assemblage of species was significantly reduced in cover by the burns testifies to a high degree of cryptogam resilience to this disturbance. The total lack of negative grazing effects suggests cryptogams are not a major source of sustenance for the local vertebrate herbivores. These conclusions differ from those made elsewhere in the world.


ISRN Ecology ◽  
2013 ◽  
Vol 2013 ◽  
pp. 1-14 ◽  
Author(s):  
R. Jayakumar ◽  
K. K. N. Nair

Study Aim. To assess species diversity and tree regeneration patterns of different vegetation types of Western Ghats, India. Rarefaction was used to estimate species diversity of different vegetation types. One-way ANOVA was used to test for differences in tree density and basal area of different vegetation types. Sorenson index of similarity was used to calculate change in species composition between mature trees and regenerating individuals. Results showed that species diversity and regeneration pattern of trees differ in different vegetation types of the forest landscape. Species-area and species-individual accumulation curve (rarefaction) against equal-sized sampling area in different vegetation types showed that species heterogeneity was higher in vegetation types at mid elevations while their abundance was higher in vegetation types at higher elevations. All the vegetation types of the study area were heterogeneously distributed. Tree regeneration was higher in species rich vegetation type with no sign of human disturbances. Change in species composition across mature and regenerating phase was more frequent in disturbed forest as compared to undisturbed or less disturbed forests. New entry species occur in all the vegetation types.


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