The effects of anthropogenic impact on plant and soil cover in Mongolia.
Under the prevailing variable natural conditions nomadic pastoralism was the most suitable form of land use in Mongolia and the neighboring countries in the past. Furthermore, small areas were used for agriculture in some regions. Therefore, anthropogenic influence was present throughout history. In the forest steppe zone this led to the disappearance of forest sites which then gave way to meadow steppe. The severe impact on the natural pastures by continuous increase of livestock herding and other human activities was perceptible during the socialist period. But since the 1990s, after the transition to market economy, this impact has increased greatly and a great number of degradation features and irreversible damages in the plant and soil cover can be observed now. Especially in the vicinity of the Mongolian capital Ulaanbaatar, along the north-south road corridor from Russia to the Chinese border, but also in some western regions of the country herders concentrate their livestock in search for better marketing opportunities. Especially there, the vegetation in vast areas is overgrazed by biting and trampling to such an extent that its regeneration is endangered. Degraded and devastated pasture types with a decrease of valuable forage plants and a high increase of ruderal elements can be found in these grasslands. Characteristic sequences of pasture degradation are presented here. The degradation effects steppes and desert steppes as well as reed, mire, and meadow vegetation in the river valleys and lowlands. In the desert regions saxaul vegetation is especially threatened. In some cases after degradation of the plant cover these degradation processes effect soil cover, too. Impacts on soil cover caused by ploughing of virgin land, by ploughing of long term used arable land, and by irrigation are the main reasons for soil degradation. Also recreational activities in the vicinity of settlement centers and traffic along the tracks lead to detrimental vegetation and soil cover changes. Unsystematic forest clearing goes on at a high level and often results in irreversible soil degradation.
Germination ecology of Central Asian Stipa spp: differences among species, seed provenances, and the importance of field studies
Stipa-species are wide-spread in Central Asia, but sexual reproduction in the dry steppes is rare. To facilitate conservation and restoration of these important rangelands, we studied germination characteristics of three common Mongolian Stipa-species under field- and lab conditions. Seeds of Stipa krylovii, Stipa gobica and Stipa glareosa were sown at the study site in Southern Mongolia over two consecutive years during which period tests were carried out to ascertain whether competition or herbivory are the main constraints of seedling establishment. In addition, we tested germination and seed viability in the laboratory under two different temperature regimes (20/10°C and 8/4°C), as well as the effect of cold-stratification. The lab experiments also included S. krylovii seeds originating from three climatically different provenances. None of the three Stipa-species seedlings emerged during the first 2 years of the field study. However, after an unusually intense rain event in the third year, 3% of S. krylovii, 0.6% of S. glareosa and 0.1% of S. gobica seeds germinated in the study plots. The factors ‘sowing-year’ and ‘vegetation’ significantly affected seedling emergence, whereas grazing had no effect at all. Under laboratory conditions a high percentage of viable seeds of S. gobica and S. glareosa germinated at both incubation temperatures, and cold-stratification had no effect on germination or viability. Germination of S. krylovii seeds required warmer temperatures and cold-stratification had a positive effect. Such evidence for dormancy was more pronounced in seeds from the moister, northern provenances. Germination of Stipa-species in the field is rare and only possible under exceptionally moist conditions. Conservation should thus concentrate on steppe conservation rather than on restoration. Where artificial reseeding is necessary, differences among species and also among different seed provenances should be taken into account.
Zwergbinsengesellschaften in der Mongolei. Ergebnisse der Mongolisch-Deutschen Biologischen Expeditionen seit 1962 Nr. 97
Aus Flusauen der Mongolischen Volksrepublik (MVR) wird anhand von Vegetations-aufnahmen uber das Auftreten von vier Gesellschaften der Zwergbinsenvegetation (Isoeto-Nanojuncetea, Cyperetalia fusci) berichtet. Es wurde eine Juncus, bufoniue-Limosella aquatica-Ges., eine Eleocharia acicularis-Schoenoplectus supinus-Ges., eine Cyperus fuscus Ges. und eine Koenigia islandica- Veronica rubricaulis-Ges. ausgeschieden. Bei der Erfassung der Zwergbinsenvegetation konnten fur das Gebiet der MVR 6 neue Arten nach-gewiesen werden: Dichostylia hamulosa, Schoenoplectw, supinus, Middendorfia borystheleica, Centaurium puchellum ssp. meyeri und Veronica rubricaulis. Die kurzlebige annuelle Zwergbinsenvegatation ist, wenn auch haufig fregmentarisch, im Gebiet der MVR wesentlich weiter verbreitet und sollte starkere Beachtung finden. 
 
 
 
The paper deals with the occurence of four plant communities of the dwarf rush vegetation (Isoeto-Nanojuncetea, Cyperetalia fusci) in the flood plains of the Mongolian People's Republic (MPR), the Juncus bufoniua-Limosella aquatica community, the Eleocharis acicularis-Schoenoplectw supinus community, the Cyperus, fuscus community, and the Koenigia islaandica-veronica rubricaulie community. 
 
 
 
Recording the dwarf rush vegetation we found five species new for Mongolia: Dichostylis hamulosa, Schoenoplectus supinus, Middendorfia borysthenica, Centaufium pulchellum ssp. meyeri, and veronica rubricaulie. 
 
 
 
The ephemerous dwarf rush vegetation is – often fragmentary – rather widespread on the territory of the MPR and needs further floristic and geobotanical investigation.