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.

Above-ground carbon storage in Pinus pumila along an alpine altitude in Khingan Mountains, Inner Mongolia of China

Abstract: The carbon (C) cycle in alpine ecosystems is sensitive to climate change, but information about the C storage in its undergrowth is scarce. In October 2017, a total of 6231 Pinus pumila (Pall.) Regel trees were investigated for above-ground growth and density in 60 sub-plots (10×10 m) from 12 stands (50 × 50 m) along the altitudinal gradient (800-1500 m a.s.l.) in Great Khingan Mountains, Inner Mongolia, Northeast China. Sites were characterized by different crown densities (CDs) from 20% to 90%. Height and root-collar diameter (RCD) were higher in stands with CDs of 40-70% than CDs of 20-30%. Stem density (SD) and crown area (CA) had a positive correlation with altitude and CD. Equations from local shrub models were used to adapt the allometric growth models for estimation. There were variations in estimated above-ground C density depending on the model and the involvement of the canopy area. Above-ground C storage in P. pumila individuals ranged from 0.05-2.46 kg tree-1, which corresponds to C storage density ranged from 0.17-37-ton ha-1. The C density in P. pumila increased with crown density instead of stem density along increasing altitudinal gradients and increasing RCD. Hence, the crown density and diameter of a P. pumila plant can be used to predict the above-ground C density of its natural population.

The Impact of Industrial Pollution with Toxic Gases on Stem Histological Parameters of Woody Plant Undergrowth under Conditions of the Southern Industrial Zone of the City of Dnipro, Ukraine

Abstract: The paper examines the influence of industrial emissions of sulphur (IV) and nitrogen (IV) oxides (the southern industrial zone of the city of Dnipro) on stem histological parameters of the autochthonous woody plant species undergrowth of Acer platanoides L. and Fraxinus excelsior L., which are natural forest edificators in the steppe zone of Ukraine. It shows that stem anatomical characteristics undergo quantitative changes in the annual undergrowth shoots of the two tree species under anthropogenic burden, with the most significant changes in the area of heavy pollution. Results indicate the decrease of such stem parameters as stem and stele diameters, wood radius and primary cortex thickness under high concentrations of SO2 and NO2 in seedlings of both species. However, this parameter drops in A. platanoides stems by reducing the collenchyme width, whereas it goes down in F. excelsior stems due to cork thickness loss. Another difference in the response of A. platanoides to the influence of phytotoxic pollutants compared to F. excelsior is the depletion of conducting elements of its phloem, which results in thinning the secondary cortex of the stem. The research findings prove high vulnerability of A. platanoides undergrowth to the chronic exposure of SO2 and NO2. Therefore, this woody species is suggested to be used as a test object in monitoring research on plants of virginal group in the technogenic areas contaminated with sulphur (IV) and nitrogen (IV) oxides.

Practical verification of food supply to game in conditions of large-scale shelterwood system

Abstract: In the hunting district Hady (897 ha), which is operated by the Křtiny Training Forest Enterprise, 383 samples of biomass utilizable as wildlife forage were collected and analysed; they were also quantified on the basis of surface coverage of grass and woody undergrowth. Grass and herbaceous biomass production in forest stands was 180,740 kg (average 0.02 kg/m 2 ), on road shoulders and other areas it amounted to 25,213 kg (average 0.150 kg/m 2 ). The greatest diversity of plant species (72) was detected on the other areas. In total, forest and other areas provide 205,953 kg of utilizable grass and herbaceous biomass available during the vegetation period. Production of woody bio- mass, i.e. buds and shoots, amounted to 307,243 kg (average 0.035 kg/m 2 ). The woody component of food in this locality was represented mainly by the species of beech, hornbeam, maple, and ash. Evaluation of sample plots revealed that the area covered by herbs and grasses in the studied forest unit was reduced due to a large-scale shelterwood system. On the other hand, a markedly increased supply of food from woody biomass was found to be available in the form of buds, leaves and shoots. The number of individuals in the advance regeneration of woody species in undergrowth ranged between 270 and 380,000 pcs/ha. Average values used for the calculation of utilizable energy in biomass were obtained from a laboratory measurement of biomass samples and complemented with data from literature. Average values of forest herbs and grasses = 0.60 MJ; buds, leaves and shoots in the growing season = 0.75 MJ. Average daily food consumption was converted to net digestible energy in MJ. In order to estimate food sufficiency with respect to quality energy requirements were calculated on the basis of the metabolic size of roe deer and hare bodies. In the quantitative assessment of available food supply, the standardized game stock would utilize 51% of grass and herbaceous forage and 7.5% of food from woody biomass. In the qualitative assessment of available food supply it was demonstrated that energy requirements of roe deer and hare were fully covered by their daily quantitative consumption of herbaceous, grass and woody biomass.

Assessing the Floristic Biodiversity and Carbon Stock in a Republic of Congo’s Forest Ecosystem

Abstract: Reforestation management goes through the knowledge of the tired out evolution after a forestry rest. The aim of this study was to assess biodi-versity concerning Terminalia superba Engl. & Diels and its undergrowth, and then quantify sequestered carbon stocks to appreciate the impact of reforestation on forest recovery and the enhancement of carbon stocks. The study was conducted at Bilala artificial forest in southeastern Republic of Congo, in Kouilou Department (Mayombe), close to Mvouti District with an altitude of 30 m. The floristic inventory was carried out in 9 rectangular sub-plots of 20 × 25 m each, installed in three blocks of Terminalia superba Engl. & Diels, for a total area of 0.5 ha. These blocks consisted of the 64, 31 and 20 years old plantations. Within ten sub-plots censuses, all trees with a DBH ≥5 cm were identified and measured. 51 trees of Terminalia superba Engl. & Diels and around 3007 trees in its undergrowth have been recorded belonging to 33 botanical families and 52 species. The results showed that the biomass recorded in this forest has been 275 t·ha﹣1 and the carbon stock was 129.6 t·ha﹣1. Terminalia superba Engl. Diels had for itself a biomass of 181.42 t·ha﹣1 out of the 275 t·ha﹣1 quantified. The amount of CO2 captured in the atmosphere by the recorded floristic procession deducted from this carbon stock was 475.89 tons of CO2, with an economic value equal to US$ 2379.45 or XAF 1,413,278. This study demonstrated that the forestry method of reforestation has a positive impact on biodiversity recovery and carbon sequestration.