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101.
广州市越秀公园鸟类多样性与保护对策 总被引:10,自引:1,他引:9
对广州市越秀公园鸟类的多样性进行了调查,共记录鸟类43种,隶属8目20科。其中留鸟27种,夏候鸟2种,冬候鸟8种,其它繁殖鸟6种。对夏冬季及不同生境的鸟类群落特征进行比较分析,得到夏季鸟类的数量、密度、优势度都比冬季高,而多样性指数和均匀性指数却比冬季低;南秀湖畔大草坪、金印游乐场、竹林、南秀树林、南秀湖和环市路旁6种生境中鸟类的种类、数量和多样性差异较大,以金印游乐场鸟类的多样性最高。根据公园内不同环境鸟类多样性状况提出了保护对策。 相似文献
102.
Correlations between environmental factors and the distribution of amphibian and reptile species richness were investigated
in a climate transition area, Peneda-Gerês National Park (PNPG), in North-Western Portugal. Using presence-data at a local-scale
(1 × 1 km), Ecological-Niche Factor Analysis (ENFA) identified a mixture of climatic (precipitation and number of days with
fog), topographical (altitude and relief) and habitat factors (number of watercourses and water surfaces, the type of the
largest water surface and tree diversity cover), as accurate predictors of species occurrence. Three factors were common for
both taxonomic groups, and consistently presented a positive relation with species occurrence: precipitation, number of water
surfaces, and tree diversity cover; suggesting a strong coincidence in the environmental correlates that influence amphibian
and reptile species richness. Distribution patterns of observed and predicted species richness were compared using a Geographical
Information System. Overall, three high species richness areas were predicted in common for both taxonomic groups and two
additional areas for amphibians only. These areas matched with the observed species richness but suggested larger areas of
high species richness. The location of the PNPG in a biogeographic crossroad, between Euro-Siberian and Mediterranean provinces,
emphasised species richness of amphibians and reptiles and suggests a high priority conservation status for this protected
area. Most of Central-Northern Portugal is located in a climatic transition area; therefore, increased species richness should
be expected for other areas. Local scale studies for other protected areas should be planned as a framework for the development
of multi-scale conservation planning by Portuguese authorities. 相似文献
103.
F. Kansiime E. Kateyo H. Oryem-Origa P. Mucunguzi 《Wetlands Ecology and Management》2007,15(6):453-467
Wetlands in Uganda experience different forms of human pressure ranging from drainage for agriculture and industrial development
to over harvesting of wetland products. In order to develop sustainable management tools for wetland ecosystems in Uganda
and the Lake Victoria Region, water quality analyses were carried out in a rural undisturbed (pristine) wetland (Nabugabo
wetland in Masaka) and two urban wetlands that are experiencing human and urban development pressure (the Nakivubo wetland
in Kampala and Kirinya wetland in Jinja). The former wetland forms the main inflow into Lake Nabugabo while the other two
border the northern shore of Lake Victoria, Uganda. Nabugabo wetland buffers Lake Nabugabo against surface runoff from the
catchment, while Nakivubo and Kirinya wetlands provides a water treatment function for wastewater from Kampala City and Jinja
town respectively, in addition to buffering Lake Victoria against surface runoff. Water quality was assessed in all the wetland
sites, and in addition nutrient content and storage was investigated in the main plant species (papyrus, Phragmites, Miscanthidium and cocoyam) in Nakivubo and Kirinya wetlands. A pilot experiment was also carried out to assess the wastewater treatment
potential of both the papyrus vegetation and an important agricultural crop Colocasia esculenta (cocoyam). Low electrical conductivity, ammonium–nitrogen and ortho-phosphate concentrations were recorded at the inflow
into Nabugabo wetland (41.5 μS/cm; 0.91 mg/l and 0.42 mg/l respectively) compared to the Nakivubo and Kirinya wetlands (335 μS/cm;
31.68 mg/l and 2.83 mg/l and 502 μS/cm; 10 mg/l and 1.87 mg/l respectively). The papyrus vegetation had higher biomass in
Nakivubo and Kirinya wetlands (6.7 kg DW m−2; 7.2 kg DW m−2 respectively), followed by Phragmites (6.5, 6.7), cocoyams (6.4, 6.6) and Miscanthidium (4.0, 4.2). The papyrus vegetation also exhibited a higher wastewater treatment potential than the agricultural crop (cocoyam)
during the pilot experiment (maximum removal degree of ammonium–nitrogen being 95% and 67% for papyrus and yams). It was concluded
that urbanisation pressure reduces natural wetland functioning either through the discharge of wastewater effluent or the
degradation of natural wetland vegetation. It is recommended that wetland vegetation be restored to enhance wetland ecosystem
functioning and for wetlands that are not yet under agricultural pressure, efforts should be made to halt any future encroachment. 相似文献
104.
We examined the impact of ploughing on soil seed banks of plant communities living in temporary marshes located in agricultural
fields. The quantity, quality and vertical distribution of seeds were quantified under ploughed or unploughed treatment at
community level. We also focussed on a typical semi-aquatic species, Damasonium alisma, to investigate the impact of ploughing at population level. We used two complementary techniques to study seed banks: hand
sorting and seedling emergence. We found that species richness of seeds, seed abundance and germination ability were strongly
affected by ploughing at community level. Concerning D. alisma, most of the seeds (56%) were stored in the two deepest soil layers among the four considered in ploughed pools. Moreover,
the germination rate was higher for buried seeds (84%) than for seeds collected at the surface (33.6%). These patterns were
almost inverted in unploughed pools. Our results agree with the temporal storage effect generally suggested to describe the
seed bank property of plant communities. But in addition, we showed that ploughing induces a spatial storage effect in accumulating
species and individuals in the seed banks that favourably influence community dynamics. We conclude that, in contrast to what
is usually thought, ploughing disturbance can be of benefit for such ephemeral wetland vegetation. 相似文献
105.
Pablo R. Stevenson 《Plant Ecology》2007,190(2):245-258
In order to assess the importance of seed dispersal (escape and colonization hypotheses), I used transplant experiments for
seeds and seedlings of 5–11 plant species with fleshy fruits in a lowland tropical forest (Tinigua National Park, Colombia).
I controlled seed density, distance to parental tree, and habitat type. I monitored seed removal, seedling survival, and seedling
growth during the first year of development for an average of 554 seeds and 169 seedlings for each species. I supplemented
the experimental results with measurements of natural recruitment. I found little support for the escape hypothesis during
the seed and seedling stages. For six species that showed differences in seed removal associated with distance, five showed
highest removal away from, than close to parent trees, suggesting predator satiation. Seedling survival during the first year
was not consistently associated with low densities and long distances from parent trees. For the majority of species, seedlings
did not survive flooding in low basins, and there was growth advantage for most plant species in canopy gaps. These differences
imply advantages for seed dispersal to adequate habitats, as predicted by the colonization hypothesis. In contrast to experiments,
strong negative distance-dependent effects were evident when analyzing natural recruitment patterns. The ratio between saplings
and seedlings was higher away from parent trees for the species with enough recruitment to be analyzed and this suggests that
a negative distance-dependent effect may also occur after seedling establishment. This pattern is suspected for several other
species, but an analysis with some of the other most common trees showed a variety of negative, neutral, and positive distance
dependent effects. This study emphasizes the importance of long-term studies to asses the role of seed dispersal. 相似文献
106.
Question: How can the U.S. National Vegetation Classification (USNVC) serve as an effective tool for classifying and mapping vegetation, and inform assessments and monitoring? Location: Voyageurs National Park, northern Minnesota, U.S.A and environs. The park contains 54 243 ha of terrestrial habitat in the sub-boreal region of North America. Methods: We classified and mapped the natural vegetation using the USNVC, with ‘alliance’and ‘association’as base units. We compiled 259 classification plots and 1251 accuracy assessment test plots. Both plot and type ordinations were used to analyse vegetation and environmental patterns. Color infrared aerial photography (1:15840 scale) was used for mapping. Polygons were manually drawn, then transferred into digital form. Classification and mapping products are stored in publicly available databases. Past fire and logging events were used to assess distribution of forest types. Results and Discussion: Ordination and cluster analyses confirmed 49 associations and 42 alliances, with three associations ranked as globally vulnerable to extirpation. Ordination provided a useful summary of vegetation and ecological gradients. Overall map accuracy was 82.4%. Pinus banksiana - Picea mariana forests were less frequent in areas unburned since the 1930s. Conclusion: The USNVC provides a consistent ecological tool for summarizing and mapping vegetation. The products provide a baseline for assessing forests and wetlands, including fire management. The standardized classification and map units provide local to continental perspectives on park resources through linkages to state, provincial, and national classifications in the U.S. and Canada, and to NatureServe's Ecological Systems classification. 相似文献
107.
108.
Non‐territorial Macaques Can Range Like Territorial Gibbons When Partially Provisioned With Food 下载免费PDF全文
Juan Manuel José‐Domínguez Marie‐Claude Huynen Carmen J. García Aurélie Albert‐Daviaud Norberto Asensio 《Biotropica》2015,47(6):733-744
Human food supplementation can affect components of animal socioecology by altering the abundance and distribution of available food. We studied the effect of food supplementation by comparing the ranging patterns and intergroup interactions of two groups of northern pigtailed macaques (Macaca leonina), a non‐territorial primate species. One group was partially reliant on food provisioning, whereas the other group foraged wild food. We also compared the macaques’ movement with that of a group of white‐handed gibbons (Hylobates lar), a territorial species inhabiting the same site. Home range, core area, and daily path lengths were significantly smaller for the semi‐provisioned group than for the wild‐feeding group. In contrast to wild‐feeding macaques, supplemented macaques showed higher fidelity to home range, core area, and particularly to the region where human food was most accessible and abundant. The relationship of daily path length and home range indicated a low defendability index for wild‐feeding macaques; the higher index for the semi‐provisioned group was consistent with the territorial pattern found in gibbons. Semi‐provisioned macaques showed further traits of territoriality with aggression during intergroup encounters. These findings indicate that human modification of food availability can significantly affect movement patterns and intergroup competition in macaques. The observed ranging dynamics related to food provisioning may decrease the efficiency of macaques as seed dispersers and increase predation on their home range, and thus have important consequences for plant regeneration and animal diversity. 相似文献
109.
本溪关门山国家森林公园游客行为特征 总被引:1,自引:0,他引:1
研究游客行为特征对于旅游资源的开发、管理以及旅游目的地的可持续发展具有重要的作用。以本溪关门山国家森林公园为研究对象,通过问卷调查的方法对游客的人口统计学特征、地域结构特征、一般行为特征、消费特征及感知特征进行了研究。结果表明:关门山国家森林公园的游客以较高学历的男性中青年为主;客源主要来自本省辽宁,并以沈阳、本溪和大连的游客为主,客源地理集中度指数为35.71;旅游的主要目的是观赏枫叶,出游时间大部分集中在每年"十一"黄金周期间,且半数以上为当日往返的短程游览者;游客偏好与家人一起出游的旅行方式,所选择的交通工具主要为自驾车和旅游专车;游客的消费结构不平衡,主要集中于景区门票和交通费,占总消费的56.7%;游客对景区的喜好度依次为龙门峡景区月台子景区小黄山景区夹砬子景区鸣翠谷景区。总的来说,游客满意度较高,有89.1%的游客愿意重游此地,游客最不满意的地方主要表现在景区卫生方面。基于调查研究结果,对关门山国家森林公园的开发建设和可持续发展提供了相关建议。 相似文献
110.
Extensive sampling for aquatic insects was conducted in the orders Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies) (EPT) of Isle Royale National Park (ISRO), Michigan, United States of America, during summer 2013. The island was ice covered until 8,000 to 10,000 years ago and is isolated by 22–70 km distance from the mainland. Two hypotheses were examined: that ISRO EPT richness would be much reduced from the mainland, and that the species colonizing ISRO would be of smaller size than mainland, adults presumably using updrafts to bridge the distance from mainland sources. Data sets were developed for known mainland EPT species and size for those species. The first hypothesis was confirmed with the mainland species pool consisting of 417 EPT, while ISRO is known to support 73 species. Richness of EPT is directly related to the number of specimens examined. Small streams supported five EPT species, while 15–25 species were found in larger streams. Lakeshores had intermediate diversity. The second hypothesis was substantiated for stoneflies, but not for mayflies or caddisflies. Stoneflies apparently are poorer fliers than either of the other two orders. 相似文献