Physical Sciences and Mathematics Commons^™

Is Degradation A Major Problem In Semi-Desert Environments Of The Gobi Region In Southern Mongolia?, Karsten Wesche, Vroni Retzer

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

This paper tests predictions derived from the non-equilibrium theory of rangeland science. Data were collected in livestock enclosures situated in the relatively moist desert steppes of the Gobi Gurvan Saykhan region of southern Mongolia from 2000 to 2003. Plant community composition and species’ richness in enclosures showed clear differences between years, but these were equally strong in ungrazed controls. Thus, changes were mainly attributed to differences in precipitation between years as opposed to grazing, as no significant effects thereof were detected. This was also confirmed by data on above-ground standing biomass. This changed tremendously over the years, with differences between …

Environmental Adaptations Of The Gobi Desert Plants In Mongolia: An Example Of C4-Plants, Ts. Tsendeekhuu, Clanton Candler Black

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

This paper presents the results of our studies on the ecological adaptations and geographical distribution of plants with C4-photosynthesis in Mongolia using ¹³C isotope discrimination.

Previous studies identified about 80 C4-species in 8 families in the Mongolian flora. Our investigations lead to the identification of four additional species, which can be regarded as C4-plants. Orostachys spinosa (-16.26‰ ¹³C), O. thyrsiflora (-16.86‰ ¹³C), O. fimbriata (-16.15‰ ¹³C), and Euphorbia humifusa (-23.29‰ ¹³C). However, as the discrimination level for Euphorbia humifusa is very similar to that of C3-plants it may be switching between C3 and C4 types …