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自然物种多样性的定量及在环境评价中的意义 被引量:3
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作者 焦六十二 《兰州大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第S1期33-41,共9页
无人为干扰的原生生态区域中的物种多样性为自然物种多样性.以"自然生态→无人为干扰→自然物种多样性→生态因子→决定因素→数量因子→数量关系→物种多样性模型"为推理线索,对己有资料进行"数学"归纳和建模意义... 无人为干扰的原生生态区域中的物种多样性为自然物种多样性.以"自然生态→无人为干扰→自然物种多样性→生态因子→决定因素→数量因子→数量关系→物种多样性模型"为推理线索,对己有资料进行"数学"归纳和建模意义上的筛选,综合出一个定量特定地理、气候区域及地理位置上的自然物种多样性公式;以"自然物种多样性→存在人为干扰→生态失衡→实有物种多样性"为推理线索,得出生态失衡公式.自然物种多样性公式用于定量特定区域中的物种多样性特征及梯度分布,生态失衡公式用于定量生态失衡程度及人为干扰大小. 展开更多
关键词 自然物种多样性 实有物多样性 数量因子 生态失衡程度 相对失衡程度
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Natural vegetation recovery on waste dump in opencast coalmine area 被引量:12
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作者 CHENGJian-long LUZhao-hua 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第1期55-57,i003,共4页
The changes of vegetation compositions, plant species diversity, species important value and succession of plant community were studied on waste dumps in Haizhou opencast coalmine which is located in the west of Liaon... The changes of vegetation compositions, plant species diversity, species important value and succession of plant community were studied on waste dumps in Haizhou opencast coalmine which is located in the west of Liaoning Province, China (41°41(-42°56( N, 121°1(-122°56(E). Four kinds of terraces with different ages (5, 10, 20 and 40 years) were selected for investigation of plants. Total of 63 species of natural colonized plants were recorded on the waste dump and they belong to 23 families. The main families were Compositae (15 species), Fabaceae (11 species) and Leguminosae (8 species), which accounted for 54.0% of total species and play an important role in natural vegetation recovery in waste dump area. The dominant species on 5-, 10-, 20-, 40-year-old terraces were Tribulus terrestris + Echinochloa hispidula + Salsola collina, Echinochloa hispidula + Artemisia sieversiana + Artemisia scoparia, Echinochloa hispidula + Clinelymus dahuricus + Artemisia scoparia + Artemisia sieversiana + Melilotus officinalis, Clinelymus dahuricus+Phragmites communis + Echinochloa hispidula+ Setaria viridis, respectively. According to the important value of species calculated. It is determined that Tribulus terrestris can act as pioneer species on waste dump and Clinelymus dahuricus, Phragmites communis and Echinochloah hispidula are important dominant species in vegetation restoration in Haizhou opencast coalmine. The study results can provide scientific basis for selecting and disposing appropriately plant species and rehabilitating vegetation on waste dumps of coalmine. 展开更多
关键词 Haizhou Opencast coalmine Waste dump Plant community RESTORATION
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Bird assemblages in natural and urbanized habitats along elevational gradient in Nainital district (western Himalaya) of Uttarakhand state, India 被引量:5
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作者 Dinesh BHATT Kamal Kant JOSHI 《Current Zoology》 SCIE CAS CSCD 北大核心 2011年第3期318-329,共12页
The Indian subcontinent is amongst the biologically better known parts of the tropics and its bird fauna has been well documented. However, avian community composition and diversity along elevational gradients and amo... The Indian subcontinent is amongst the biologically better known parts of the tropics and its bird fauna has been well documented. However, avian community composition and diversity along elevational gradients and amongst habitat types remains unclear in India. We attempted to estimate bird assemblages in terms of diversity, species composition, status and abun- dance in urban and forest habitats of Nainital district of Uttarakhand (350-2450 m asl; 29N), Western Himalayas. We sampled different elevational gradients and to understand the effect of urbanization and season on avian community composition. Field studies were conducted during January 2005 to January 2007. Results indicated that the forest had more complex bird community structure in terms of higher species richness (14.35 vs 8.69), higher species diversity (Shannon's index 4.00 vs 3.54), higher evenness (0.838 vs 0.811) and more rare species (17 vs 5) as compared to urban habitat. However, the abundance of 11 species was higher in urban habitats. Bird Species Richness (BSR) varied considerably among study areas (91 to 113 species), was high- est (113 species) at mid elevation (1450-1700 m asl) and decreased (22 species) at high elevation (1900-2450 m asl). It seems that high BSR at mid altitudes is not caused by the presence of a group of mid altitude specialists but rather that there is an over- lap in the distribution of low land and high elevation specialists at this altitude. BSR and Bird Species Diversity fluctuated across seasons but not habitat type [Current Zoology 57 (3): 318-329,2011]. 展开更多
关键词 Avian biodiversity Western Himalaya URBANIZATION
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Projected impacts of climate change on protected birds and nature reserves in China 被引量:11
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作者 Xueyan Li Nicholas Clinton +3 位作者 Yali Si Jishan Liao Lu Liang Peng Gong 《Science Bulletin》 SCIE EI CAS CSCD 2015年第19期1644-1653,共10页
Knowledge about climate change impacts on species distribution at national scale is critical to biodi- versity conservation and design of management programs. Although China is a biodiversity hot spot in the world, po... Knowledge about climate change impacts on species distribution at national scale is critical to biodi- versity conservation and design of management programs. Although China is a biodiversity hot spot in the world, potential influence of climate change on Chinese protected birds is rarely studied. Here, we assess the impact of climate change on 108 protected bird species and nature reserves using species distribution modeling at a relatively fine spatial resolution (1 km) for the first time. We found that a large proportion of protected species would have potential suitable habitat shrink and northward range shift by 77-90 km in response to projected future climate change in 2080. Southeastern China would suffer from losing climate suitability, whereas the climate conditions in Qinghai-Tibet Plateau and northeastern China were projected to become suitable for more protected species. On average, each protected area in decline of suitable climate for China would experience a 3-4 species by 2080. Cli- mate change will modify which species each protected area will be suitable for. Our results showed that the risk of extinction for Chinese protected birds would be high, even in the moderate climate change scenario. These findings indicate that the management and design of nature reserves in China must take climate change into consideration. 展开更多
关键词 Climate change impact Protected bird species Habitat suitability Range shift Species distribution model
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