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| Responses of distribution of Artemisia sacrorum community to climate in semi-arid and semi-humid areas of Loess Plateau |
| Cheng Jie1, Hu Tianming2, Cheng Jimin2 |
| 1. Institute of Forest Inventory and P lanning of Northwestern China, State Forestry Administration, 710048, Xi'an; 2. College of Animal Science and Technology, Northwest A&F University, 712100,Yangling, Shannxi: China |
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Abstract During 2000—2009, field survey and position monitoring were employed to find out responses of the distribution and growth region of Artemisia sacrorum community to climate in forest steppe zone, typical grassland zone and desert steppe zone of Loess Plateau. Affected by the temperature, suitable growth range of Artemisia sacrorum community presented obvious zonality distribution from sourtheast to northwest, namely, forest steppe zone> typical grassland zone >desert steppe zone, with population density 12.6 plants/m2, 8.8 plants/m2, 4.6 plants/m2respectively and reproductive branches 19 per cluster, 14 per cluster, 3 per cluster respectively. Affected by the rainfall gradient, the horizontal distribution of Artemisia sacrorum expanded from forest steppe zones to the typical grassland zone, which means it became the dominate species instead of the companion species. Also, it appeared as the occasional species on gullies and valleys and sand dunes in the desert steppe zone. Therefore, its optimal rainfall limits changed from 500-750mm to 200mm. In addition, Artemisia sacrorum extended from its optimal vertical elevation of 1900m to 2200m above sea level. Furthermore, the conclusion indicated that in the condition of global climate changes, Artemisia sacrorum as a typical indicting plant gradually widened its ecological amplitude and has become the steady vegetation type in forest steppe zone and typical grassland zone.
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Received: 26 August 2010
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