Importance of field weeds species diversity
Trzcinska-Tacik, H.(Uniwersytet Jagiellonski, Krakow (Poland). Inst. Botaniki)
The problem of biodiversity can be considered on the global or local level. The global diversity can be only estimated approximately, because of our weak knowledge of the complete list of species on the Earth. Local diversity can be measured by the number of species on the known area (=richness). The number of species depends on the area: the bigger area - the higher the number of species. However this relationship is connected with homogeneity of habitat. Heterogeneity of habitat causes an increase of the number of species. Local diversity is usually considered on three levels: alpha-richness of one type community, beta-number of communities of the area, gamma-multiple alpha and beta
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