911 research outputs found
The choice of strategy - differentiation of growth points
В статье дается характеристика состояния высшего технического образования России, высказывается идея о чрезвычайной актуальности инженерного образования на современном этапе.This article characterizes a current state of the higher technical education in Russia, it suggests urgent necessity of engineering education at the present stage
A case study of a plant-animal relationship: Cola lizae and lowland gorillas in the Lope Reserve, Gabon
The fruits of Cola lizae, an endemic tree with a limited geographical distribution, have been a major food source for lowland gorillas in the Lope Reserve during part of each year over a six-year period. Faecal analysis indicated that 11,000- 18,000 Cola seeds km-2 were deposited by gorillas during the 4- month season in 1989. Gorillas are the only important dispersers of this species: other primates consume the succulent mesocarp, but do not swallow the large seed; elephants do not eat Cola fruits. Observations of Cola seeds in gorilla faeces showed a very high germination rate and, despite initial high mortality, 18% of seedlings still survived six months after deposition. Survival of seedlings was significantly better in faeces left at nest-sites than in other areas of the forest: 40% of seedlings were viable at nest- sites six months after deposition. This suggests that the open areas of forest, preferred by gorillas as nest-sites, are advantageous to the propagation of this species
The graduate school — choice of strategy
В статье дается характеристика состояния высшего технического образования России, высказывается идея о чрезвычайной актуальности инженерного образования на современном этапе.This article characterizes a current state of the higher technical education in Russia, it suggests urgent necessity of engineering education at the present stage
Seasonal feeding on bark by gorillas: an unexpected keystone food?
First paragraph: There are a number of reports in the literature of primates feeding on the bark of trees, but bark has only occasionally been considered as a major food to be studied in its own right (e.g., Waser, 1977; Beeson, 1987; Norris, 1988). All the great apes feed on bark at certain times, and clearly have preferences as to which species they choose (e.g., Schaller, 1963; Jones & Sabater Pi. 1971; Casimir, 1975: Nishida, 1976; Goodall, 1977; Rodman, 1977; Sabater Pi, 1977, 1979). Evidence has been presented that bark feeding by chimpanzees (Pan troglodytes) and orangutans (Pongo pygmaeus) is a seasonal phenomenon related to scarcity of preferred fruits (Nishida, 1976; Rodman, 1977), and similar conclusions have been drawn from studies of blue monkeys (Cercopithecus mitis) living near plantations of exotic pines (Beeson, 1987; Maganga & Wright, 1992). Bark feeding is also well known in other mammals where, again, it often occurs seasonally (e.g., elephants, Wing & Buss, 1970; grey squirrels, Kenward & Parish, 1986)
Can management intensity be more important than environmental factors? A case study along an extreme elevation gradient from central Italian cereal fields
This paper aims to assess the importance of environmental and management factors determining the weed species
composition along a strong elevation gradient. A total of 76 cereal fields (39 low input and 37 intensively managed) were
sampled along an elevation gradient in central Italy. Explanatory variables were recorded for each field to elucidate the role of
large-scale spatial trends, of site-specific abiotic environmental conditions and of field management characters. Redundancy
analysis was used to assess the relative importance of each environmental variable in explaining the variation in species
composition. Our results indicate that variation in weed species composition is strongly determined by altitude, mean annual
precipitation, mean annual temperature and also by soil characteristics. However, the level of intensification proved to be the
most influential variable. There was a significant difference in species richness and composition between low-input and
intensively managed fields. Intensification leads to considerable species loss at both lower and higher elevations. Low-input
fields had 296 species in total, while intensively managed fields had only 196
Effects of the dry season on gorilla diet in Gabon
It has been shown by various workers that lowland gorillas, Gorilla g. gorillas, in Gabon eat large quantities of succulent fruits (TUTIN and FERNANDEZ, 1985, WILLIAMSON, 1988,WILLIAMSON et al., 1988). This is now being extended to include analysis of the nutrient content of fruit foods, and to study annual variations in fruit consumption caused by, for example, the major dry season from June to September
The effects of stand characteristics on the understory vegetation in Quercus petraea and Q. cerris dominated forests
The shelterwood system used in Hungary has many effects on the composition and structure of the herb layer. The aim of our study was to identify the main variables that affect the occurence of herbs and seedlings in Turkey oak-sessile oak (Quercus cerris and Q. petraea) stands. The study was carried out in the Bükk mountains, Hungary. 122 sampling plots were established in 50-150 year old oak forests, where we studied the species composition and structure of the understorey and overstorey. The occurence of herbs was affected by canopy closure, the heterogenity and patchiness of the stand, the slope and the east-west component of the aspect. The composition of saplings was significantly explained by the ratio of the two major oak species in the stand and the proximity of the adult plants. An important result for forest management was that sessile oaks were able to regenerate almost only where they were dominant in the overstorey
Resilience in the mountains: biocultural refugia of wild food in the Greater Caucasus Range, Azerbaijan
Diversity of traditional ecological knowledge (TEK) created on the edges of culture is the key to the sustainability and resilience of humankind. We recorded wild food TEK among seven autochthonous linguistic communities living on both sides of the Greater Caucasus Range, documenting the use of 72 wild taxa as well as remarkable diversity of both taxa and uses among the communities. The most isolated communities form distinct biocultural refugia for wild food plants and their uses, but the sustainability of such communities is under threat due to depopulation, and their TEK has already entered into decline. While isolation may have been responsible for the preservation of food biocultural refugia, it may no longer be enough for the passive preservation of the food refugia in the study area in the future. More proactive steps have to be taken in order to ensure the sustainability of TEK of the study communities and beyond
Ammi visnaga (L.) Lam. (Apiaceae), a new taxon in Croatian flora
During floristic research into the island of Bra~ (Dalmatia, Croatia) in 2010, Ammi visnaga (L.) Lam. (Apiaceae), a new neophyte for Croatia was found in several localities and natural habitats. At the altitude of 380–460 m above sea level, mostly in habitats disturbed by humans, the located populations were composed of numerous and vital specimens in blooms and with fruits. The gradual and successful integration of this species into the natural vegetation was noticed, particularly in grasslands of the association Brachypodio retuso-Trifolietum stellati Horvati} 1958 and macchia of the association Fraxino orno-Quercetum ilicis Horvati} (1956) 1958
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