Biomedical subjects

Deyong Yu

Publications and source records attributed to Deyong Yu.

4 recordsLinked to original sources

PubMed2004

[Utilization suitability of forest resources in typical forest zone of Changbai Mountains].

Conservation of natural forest does not simply equal to no logging. The Northeast China Forest Region has a logging quota of mature forest as part of natural forest conservation project. How to determine the logging spots rationally and scientifically is very important. Recent scientific theories of forest resources management advocate that the utilization of forest resources should stick to the principle of sustaining use, and pay attention to the ecological function of forest resources. According to the logging standards, RS and GIS techniques can be used to detect the precise location of forest resources and obtain information of forest areas and types, and thus, provide more rational and scientific support for space choice about future utilization of forest resources. In this paper, the Lushuihe Forest Bureau was selected as a typical case in Changbai Mountains Forest Region to assess the utilization conditions of forest resources, and some advices on spatial choice for future management of forest resources in the study area were offered.

China↗

PubMed2004

[Landscape pattern variation of forest resources in typical forest zone of Changbai Mountains].

Based on GIS and RS data of 1985 and 1999 and the ground information from Lushuihe Forest Bureau, this paper studied the forest landscape pattern and its changes in typical forest zone of Changbai Mountains. According to the standard variance of patch areas in 1985 and 1999, the patch area distribution of mature conifer forest, mature broad-leaved forest, middle-aged conifer forest, and middle-aged broad-leaved forest was less symmetrical, showing that these land covers had landscape diversity and species diversity. According to landscape similarity index, the mature conifer forest, mature broad-leaved forest, middle-aged conifer forest and middle-aged broad-leaved forest, which were relatively stable than other land covers, made the majority of the landscape in the study area. According to patch density, the porosity of wetland was high in 1985 and 1999, indicating that wetland had little homogenization and formed more mosaics. The fragmentation extent of farming land, due to multiple cultivating types, azimuths and shapes, was high in both phases. Attributing greatly to anthropogenic factors, the fragmentation extent of wetland was high all along. In brief, the forest landscape pattern was changed greatly in the studied phases, and human activities affected heavily on it.

Biodiversity↗

PubMed2004

[Research advances in bryophyte ecological function].

Though the body of bryophyte is small, its species is abundant (about 23,000), being an important part of biodiversity. The previous studies were focused on its taxology, while its ecological functions in ecosystem were ignored. Bryophyte can adapt to various environments, distribute in many extreme surroundings, and has rebuilding ability to environments. It has a very strong ability of holding and absorbing water, especially the epiphytic bryophyte can intercept a great deal of rain, and its function in water circulation is very obvious. Bryophyte can absorb a lot of nutrient elements by body surface, but its function in nutrient cycling was usually ignored. In some extreme environments, bryophyte is the important primary producer. Sphagnum biomass is more enormous, and maybe, is the important C pool. Bryophyte can sensitively response to the air and heavy metal pollution, and is a kind of bio-indicators. In order to promote the further studies on bryophyte ecological function, the related research advances were reviewed in this paper.

Biodiversity↗

PubMed2002

[Alpha diversity of communities and their variety along altitude gradient on northern slope of Changbai Mountain].

From 700 to 2600 m on northern slope of Changbai Mountain, twenty plots were investigated with an interval of 100 m in altitude, and alpha diversity of communities and their variety along altitude gradient were studied. The results showed that in different successional layers of trees, or shrub and herb layers, richness and diversity decreased linearly with the increase of altitude. Tree species decreased from 19 species at 700 m to only 1 species at timberline. Shrub and herb species decreased from 20 and 61 species at 700 m to 2 and 15 species at 2600 m respectively. The peak values of richness of trees and herbs along altitude gradient were appeared just in the ecotones between different types of vegetation, and it reflected the characteristics of high species richness in ecotones.

Altitude↗