Undergrowth

About: Undergrowth is a research topic. Over the lifetime, 795 publications have been published within this topic receiving 11911 citations. The topic is also known as: understorey & underbrush.

Vertical stratification of scolytine beetles in temperate forests.

Abstract: Although most studies exploring the vertical distribution of arthropods in forests have been limited to discrete comparisons between understorey and canopy, few have sampled across multiple heights. We studied vertical distribution of scolytine beetle flight activity in temperate lowland broadleaf and montane beech-fir forests using flight interception traps arranged in vertical transects with traps placed 0.4, 1.2, 7, 14, and 21 m above ground. In each forest type 15 vertical transects (75 traps) were used. The assemblages sampled at 0.4 and 1.2 m above ground (undergrowth) clearly differed from those at 7, 14, and 21 m (midstorey and canopy). Ambrosia-fungi feeder abundance peaked at 1.2 m in the mountains, whereas in the lowland they were almost evenly distributed from 1.2 to 21 m. Phloem feeders were significantly more abundant in the midstorey and canopy than in the undergrowth. Height preferences of eleven species were identified. Four species were associated with traps exposed at 7, 14, or 21 m, whereas seven species were associated with the height of 1.2 m. No species was associated with the 0.4 m height. To cover entire scolytine assemblages of forest stands, sampling should thus not be restricted to the usually sampled understorey level, but also cover the canopy.

Plant composition and growth of wild Coffea arabica: Implications for management and conservation of natural forest resources

Abstract: The montane rainforests of Ethiopia are the only places of origin and genetic diversity for Coffea arabica species. These natural forest areas with the occurrence of wild coffee gene pools are however under constant threats, largely due to anthropogenic activities. The study aims to determine the variability in plant compositions and growth of wild Coffea arabica trees in the natural forests of southeastern and Southwestern Ethiopia. The data were collected at twelve study sites. The dominant plants were broadly classified into three forest canopy strata with varying vegetation coverage among and within the study forests. The average abundance of large shade trees, wild coffee plants and shrubs was highest at Berhane-Kontir, Yayu and Bonga natural forests, respectively. The frequency of the respective plant forms was highest at Birhane-Kontir (61%), Harenna (53%) and Bonga (68%). The occurrence of the semi-domesticated spices crops was higher in the Bonga and Berhane-Kontir forests. The average plant density followed the descending order of Bonga>Yayu>Birhane-Kontir>Harenna forest, largely reflecting anthropogenic impacts. There was negative association between the growth of the coffee trees and the undergrowth shrubs. In contrast, the upper canopy large trees and coffee plants had direct relationships. However, the vegetative and reproductive growth responses of wild coffee plants were impaired, partly due to the multiple stresses in the dense forest ecology. Consequently, more than 70% of the total surface area of coffee trees did not bear crops and altogether coffee yield was low. The highest and lowest reproductive efficiencies were obtained from the Harenna and Yayu wild coffee populations, demonstrating the levels of coffee forest management practices. Overall, our findings indicated great variations in the patterns of plant co-existences and growth natures of wild coffee trees and underlines in multiple benefits of coffee forest environments, among others, as natural coffee gene pools. This depicts the need for multi-site in situ conservation and environmental management planning for sustaining biodiversity conservation and maintaining ecosystem goods and services in Ethiopia and worldwide. Key words: Biodiversity, Ethiopian wild coffee, genetic conservation, natural coffee forest, plant composition.

Phytodiversity of Dipterocarpus turbinatus Gaertn. F. (garjan) undergrowths at Dulahazara Garjan Forest, Cox's Bazar, Bangladesh.

Abstract: The Phytodiversity of Garjan ( Dipterocarpus turbinatus Gaertn.f.) undergrowth was studied on 4 seasons during September 1994 to .July 1995 by random quadrat method at Dulahazara Garjan forest. 85 undergrowth species belonging to 43 families were recorded and classified into 2 Ferns of 2 families, 15 Monoeot species of 8 families, 65 Dieot species of 33 families and the rest 3 species are still unidentified. Maximum number of undergrowth species were found in Leguminosae and Euphorbiaceae of Dicot, and Gramineae and Commelinaceae of Mono cot. Various life forms of the undergrowth such as Epiphytes (1.18%), Megaphanerophytes (18.82%), Microphanerophytes (29.4%), Nannophanerophytes (20%), Hemicryptophytes (7.06%), Chamaephytes (15.29%), Hydrophytes (4.71%), Therophytes (1.18%) and Geophytes (2.35%) were determined and plant climate was termed as Micro-nanno-megaphanerophytes. The undergrowth species were further classified into tree (18), shrub (23), undershrub (6), herb (14), climber (17), grass (3), sedge (2) and fern (2) species. Maximum undergrowth species were recorded during monsoon. The species diversity and diversity index of undergrowth species were calculated following Shannon-Wiener's diversity function (H) and Simpson's diversity index (D) and the result revealed that protected site led with highest values of species diversity. The present study suggests that Garjan plants and assocrated undergrowths are being degraded mainly by leaf-litter fall and wood collection, grazing, firing, soil erosion, unplanned logging etc. which may bring an alarming change in the whole Garjan forest ecosystem as well as the gene pool of existing phytodiversity.

Elemental concentrations in a tropical montane rain forest in Sri Lanka

Abstract: As a preliminary to studies on biogeochemistry of a tropical montane rain forest at about 1800 m altitude in Sri Lanka, the concentrations of 17 chemical elements in different forest compartments, i.e. in leaves of six floristically dominant tree species, undergrowth, litter, and soil at 0–10 cm and 11–60 cm depth were determined. Foliar chemical differences between species were large. Mean leaf water content, mean leaf area per leaf, and specific leaf weight of each species were also determined. Calcium seems to be used in relatively large quantities by these plants. Phosphorus concentration in all compartments was consistently low. A few species investigated appeared to concentrate aluminium and silicon at high amounts. Concentration differences between compartments were significant only for certain elements. Location effect on the concentrations in soil was considerable for most of the elements studied. When studying plant-soil chemical interactions in these forests, species-level concentrations must be taken into account as the species-specific chemical differences are obscured when treated as canopy leaves.