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991.
IAN S. SEIFERLING RAPHAËL PROULX PEDRO R. PERES‐NETO LENORE FAHRIG CHRISTIAN MESSIER 《Conservation biology》2012,26(4):610-618
Abstract: Protected areas cover over 12% of the terrestrial surface of Earth, and yet many fail to protect species and ecological processes as originally envisioned. Results of recent studies suggest that a critical reason for this failure is an increasing contrast between the protected lands and the surrounding matrix of often highly altered land cover. We measured the isolation of 114 protected areas distributed worldwide by comparing vegetation‐cover heterogeneity inside protected areas with heterogeneity outside the protected areas. We quantified heterogeneity as the contagion of greenness on the basis of NDVI (normalized difference vegetation index) values, for which a higher value of contagion indicates less heterogeneous land cover. We then measured isolation as the difference between mean contagion inside the protected area and mean contagion in 3 buffer areas of increasing distance from the protected‐area border. The isolation of protected areas was significantly positive in 110 of the 114 areas, indicating that vegetation cover was consistently more heterogeneous 10–20 km outside protected areas than inside their borders. Unlike previous researchers, we found that protected areas in which low levels of human activity are allowed were more isolated than areas in which high levels are allowed. Our method is a novel way to assess the isolation of protected areas in different environmental contexts and regions. 相似文献
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995.
一株低温高效植物油降解菌的驯化筛选及固定化研究 总被引:1,自引:1,他引:0
为了解决因低温而导致的废水中油脂难以处理的问题,从冬季重庆大学餐厅排污管道的底泥中分离出1株可低温降解植物油的菌株DJ-1。将此菌株多次驯化培养后,在5℃条件下利用其对含20g/L菜籽油复筛培养基的模拟含油废水进行处理。经过3 d处理,可去除废水中70.63%的植物油。经16S rDNA测序分析,该菌株为假单胞菌的一个未定种属(相似度为99%)。使用泥炭和木屑作为固定化载体,按照m(泥炭)∶m(木屑)∶m(菌液)=1∶4∶20的比例将扩培后的DJ-1菌剂制作成细菌固定化菌粉。在5℃条件下利用菌粉对含20 g/L菜籽油复筛培养基的模拟含油废水进行处理,菌粉投加量为0.15 g/L。经过3 d处理,废水中植物油的降解率达到77.34%,5 d后达到85.22%。 相似文献
996.
Ecology-based tourism, which is integrated with nature, developed in environmentally conscious areas and enriched by different cultures, has become more important in the direction of extending tourism throughout the year. While the landscape values of the area are important functions for tourism activities to be carried out in natural characteristics, the preferences of the users are also important. Ecology-based tourism, which develops in connection with the concepts of intacteness, the protection-use balance and sustainability, and the demands and expectations of tourists, constitute the basis of our study. For this purpose, the study was carried out in Kumyaka, a small coastal neighborhood (village) of the county of Mudanya in the province Bursa, Turkey with important natural, historical and cultural assets. Fieldwork, field analysis, literature search, interviews with tourists coming to the field, interviews with the day trippers and survey work were conducted in the study. While evaluating the ecology-based tourism potential of the area, the demands and expectations of tourists have been taken into account together with the available area data. According to the results of the survey, tourists are mostly interested in having the most scenic value and quietness when choosing the area. The types of tourism that tourists most wanted to experience in the field were 42.38% culture tourism and 32.32% nature tourism. As a result of tourists’ demands and expectations, the tourism activities to be carried out in accordance with the possibilities of the area were examined and ecology based planning proposals and holistic planning approaches were developed. 相似文献
997.
Lian Yang Qinxue Wen Zhiqiang Chen Ran Duan Pan Yang 《Frontiers of Environmental Science & Engineering》2019,13(3):32
998.
Jiuhui Qu Hongchen Wang Kaijun Wang Gang Yu Bing Ke Han-Qing Yu Hongqiang Ren Xingcan Zheng Ji Li Wen-Wei Li Song Gao Hui Gong 《Frontiers of Environmental Science & Engineering》2019,13(6):88
999.
Luxi Zou Huaibo Li Shuo Wang Kaikai Zheng Yan Wang Guocheng Du Ji Li 《Frontiers of Environmental Science & Engineering》2019,13(6):83
1000.
Yong Li Caihong Li Yanhai Zheng Guanglei Wu Tana Wuyun Hong Xu Xinhua He Gaoming Jiang 《环境科学学报(英文版)》2011,23(2):255-265
Combined e ects of ozone (O3) and cadmium (Cd) on growth and physiology of winter wheat (Triticum aestivum L. cv. JM22)
were determined. Wheat plants were grown without or with Cd and exposed to charcoal-filtered air (< 10 ppb O3) or elevated O3
(80 5 ppb, 7 hr/day) for 20 days. Results showed that O3 considerably depressed light saturated net photosynthetic rate (–20%),
stomatal conductance (–33%), chlorophyll content (–33%), and total biomass (–29%) without Cd. The corresponding decreases were
further enhanced by 45%, 56%, 60% and 59%, respectively with Cd, indicating a synergistic e ect of O3 and Cd on wheat. Ozone
significantly increased the activity of superoxide dismutase (46%), catalase (48%) and peroxidase (56%). However, great increases
in malondialdehyde (MDA) content (2.55 folds) and intercellular CO2 concentration (1.13 folds) were noted in O3+Cd treatment
compared to control. Our findings demonstrated that the increased anti-oxidative activities in wheat plants exposed to O3+Cd might
not be enough to overcome the adverse e ects of the combination of both pollutants as evidenced by further increase in MDA content,
which is an important indicator of lipid peroxidation. Precise prediction model on O3 damages to crop should be conducted to ensure
agricultural production security by considering environmental constraints in an agricultural system in peri-urban regions. 相似文献