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.

Analysis of the characteristic of the pine undergrowth after ground fire in the leningrad region

Abstract: In the article features are considered after forest fire regeneration processes in pine stands in the Luga and Putilov landscapes related to two forest districts of the Leningrad region. Quantitative and qualitative comparative analysis was carried out with the help of statistical methods of investigation: dispersion and rank analysis. The quantitative differences in the renewal dynamics of pine in cowberry and bilberry forest types on post-pyrogenic sites and under the parent stand in both regions of the study were determined based on the analysis of variance. The study showed a significant difference in the successful resumption of pine after a grass-roots fire for the Luzhsky and Kirovsky forestry’s. The use of rank analysis using the Spearman coefficient made it possible to establish differences in the qualitative characteristics of pine undergrowth and to reveal the nature of the orientation of reforestation processes after grass-roots fires. The conducted research has shown that landscape conditions exert a great influence on the nature of pine renewal, on the indicators of occurrence, vital state, abundance. The indicator of rank evaluation of the qualitative characteristics of pine undergrowth allowed them to compare and identify those that are crucial for growth under certain conditions. It is concluded that the landscape and soil-hydrological growth conditions are the leading factors in the quantitative representation of the undergrowth that arose after the grassland fires, and, depending on these conditions, a pioneering growth strategy for pine as a species is manifested. The study showed that in the same forest-typological conditions, but in different landscape areas, the renewal of pine can differ in its quantitative and qualitative characteristics.

Dynamics of Salix caprea L. populations during forest regeneration after strong herbivore pressure

Abstract: Broadleaved forest communities degenerated through strong pressure from large herbivores. Relief of this pressure led to regeneration, in particular of Salix caprea and other light-seeded pioneer trees: Populus tremula, Betula pendula and B. pubescens. This regeneration proceeded fol- lowing conservation protection of degenerate stands in a na- ture reserve and later in Bialowie2a National Park. The emer- gence and development of the Salix caprea population pro- ceeded following the expansion of Picea abies, which coin- cided with the period of enhanced animal pressure on the broadleaved forest. Salix caprea filled all the gaps in the tree stand after the destruction of trees and undergrowth by herbiv- ores (in the years 1892- 1915). The species also appeared abundantly in old, at the time unforested, clearings and felled areas. Here, S. caprea developed large populations with certain trees in good condition, with a growth form typical of forest trees and attaining considerable heights. The majority of trees were 50 - 60 yr old at the time of death, although some individuals reached 74 yr of age. The process of extinction of the Salix population - observed over 19 yr on permanent plots with marked trees - proceeded very quickly, especially in the first decade of observation. It led to the almost complete disappearance of S. caprea from the forest communities of Bialowie2a National Park. The death of individual trees is

Seasonal and diel activity of Ixodes ricinus (Acari: Ixodidae) subpopulations in Denmark. Aspects of size, physiological age, and malate dehydrogenase genotype in a forest site without any undergrowth

Abstract: The underlying population dynamics and the behavioural patterns of the vectors are key issues in understanding the transmission of vector borne pathogens. For the tick Ixodes ricinus both seasonal and diel activity have been described as bimodal patterns, which in seasonal aspect has been interpreted as representing two cohorts. However, recent studies have shown that this interpretation may be incorrect. The aim of this study was to obtain more detailed information on nymph host seeking by studying subpopulations of ticks during the day and season. The study was designed to allow for comparisons of the diel variation and seasonal variation in their dependency in a number of tick characteristics. The study took place in a forest with planted beech trees without any undergrowth. Ticks were collected by flagging the dead leaves on the forest floor. For each nymph, a number of visual observations were made. The size and physiological age was observed and the nymphs were genotyped in the malate dehydrogenase locus (MDH, E.C. 1.1.1.37). Briefly the main results can be given as: (i) There were significant differences in the composition of size classes during the season, but only limited trends in time. (ii) The proportion of the small nymphs was highly variable, with a variation from 3% to 24% in October and September, respectively. (iii) The diel variation in MDH genotypes was significant in May and August. (iv) Nymph size classes and physiological age appeared to interact. The non-random interaction was caused by a relatively even distribution of small nymphs in all four age classes, while large nymphs tended to fall into age class 2 and 3. The length by age interaction for the individual months was noted to be significant in May, July, August and September, but not in June. Similarly the interaction was significant in the morning and afternoon, but not at midday. The overall results describe the seasonal and diel activity patterns as changing systematically for several characteristics under the influence of weather condition and population dynamics. In conclusion: The observations are best interpreted as being produced of a single cohort of ticks, but the revealed complexity of the host seeking activity suggest that measures of activity × abundance should be interpreted very cautiously in relation to population dynamics.

Establishment and growth pattern of Pinus pumila under a forest canopy in central Kamchatka

Abstract: We investigated the spatial distribution and growth of the Siberian dwarf pine (Pinus pumila) in a valley–foothill larch–birch (Larix cajanderi–Betula platyphylla as canopy trees) mixed forest of fire origin located in central Kamchatka with the aim of elucidating the ecological features of P. pumila when it is an undergrowth species in a forest. The spatial distribution of all individuals of all tree species was clumped, and the spatial distribution of the two canopy tree species did not repulsively affect that of P. pumila (i.e., its establishment site). These results suggest that the regeneration of P. pumila does not depend on canopy gaps. However, the analysis using a growth model indicated that the canopy trees negatively affected the growth of P. pumila and that the negative effect of L. cajanderi on P. pumila growth was stronger than that of B. platyphylla. The direction of the crown extension of P. pumila was weakly related to the open-space direction. Our results suggest that, although the spatial pattern of establishment of P. pumila is not repulsed by the distribution of canopy trees, the crown can spread horizontally toward the more sparsely populated areas of the canopy trees where they may have higher growth rates.

Ganoderma undergrowth bionics wild cultivation method

Abstract: The invention discloses a ganoderma undergrowth bionics wild cultivation method. The method comprises the steps of A, choosing a wild ganoderma variety in the South China area and separating a mother culture; B, choosing a cut-log; C, cutting the cut-log into wood sections with the length of 20-30 cm; D, putting the cut-log into fungus bags; E, putting the bagged fungus material into a sterilization room; F, putting strains on an inoculation shelf and conducting space sterilization; G, when inoculation is conducted, pinching the strains into small blocks of 2-4 cm with hands; H, choosing a room with good thermal insulation performance as a cultivation room, wherein the room temperature is at 25-28 DEG C; I, choosing a Chinese fir forest, a weed tree forest or a bamboo forest with the canopy density of 0.6-0.8, good ventilation and drainage performance and loose and fertile soil texture as a ganoderma cultivation plot; J, choosing Spring Festival to the end of the second month in lunar calendar as cultivation time; K, removing the bags and burying fungus sticks, wherein the burying density is 1500-3000 sticks/mu (a Chinese area unit and is equal to 666.67 m ). The ganoderma undergrowth bionics wild cultivation method mainly aims at undergrowth planting of ganoderma fungus sticks in the South China area, according to the method, no facilities and manual watering are needed, continuous harvest for many years can be achieved, and the ganoderma is high in yield and good in quality.