Palaearctic grasslands in transition : overarching patterns and future prospects
The Palaearctic biogeographic realm extends over some 45 million km² and thus more than 1/3 of the terrestrial ice-free surface on Earth. It comprises extensive grasslands of different types and origin, which can be subdivided into (1) natural grasslands with (1a) steppes (climatogenic in dry climat...
| Main Authors: | , |
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| Format: | Text |
| Language: | English |
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CRC Press
2018
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| Online Access: | https://hdl.handle.net/11475/1498 https://digitalcollection.zhaw.ch/handle/11475/1498 |
| Summary: | The Palaearctic biogeographic realm extends over some 45 million km² and thus more than 1/3 of the terrestrial ice-free surface on Earth. It comprises extensive grasslands of different types and origin, which can be subdivided into (1) natural grasslands with (1a) steppes (climatogenic in dry climates), (1b) arctic-alpine grasslands (climatogenic in cold climates) and (1c) azonal and extrazonal grasslands (pedogenic and topogenic) as well as (2) secondary grasslands created and sustained by human activities, such as livestock grazing, mowing or burning. Grasslands of the Palaearctic do not only form a major basis for the agriculture of the region and thus its food supply, but are also crucial for other ecosystem services and host a supraproportional part the realm’s plant and animal diversity. To reflect that suitability of grasslands for biodiversity strongly depends on their state, we apply the term High Nature Value (HNV) grassland to those natural grasslands that are not degraded (we call them in good state) and those secondary grasslands that are not intensified (we call them semi-natural). The synthesis at hand introduces seven comprehensive regional chapters organized by the Eurasian Dry Grassland Group (EDGG) on diversity, management and conservation of grasslands of the Palaearctic, covering nearly the complete extent of this realm. After introducing the EDGG as a leading international network dealing with these topics, we take advantage of the information compiled in the regional chapters and the expertise present among their 28 authors from 17 different countries to compile for the first time statistics on grassland types and areas as well as rankings of relative importance of factors reducing their biodiversity for the whole Palaearctic biogeographic realm and its major subdivisions (Western and Northern Europe; Eastern Europe; Mediterranean Basin and the Middle East; Russia; Kazakhstan and Middle Asia; China and Mongolia; Japan). We conclude that the current grassland area in the realm is about 9.7 ... |
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