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881.
Ornamental Plants as Invasive Aliens: Problems and Solutions in Kruger National Park,South Africa 总被引:1,自引:0,他引:1
The most widespread invasive alien plant species in South Africa’s Kruger National Park (KNP) were either introduced unintentionally
along rivers and roads, or intentionally for use as ornamentals. We examine the spatial distribution of ornamental alien plants
in KNP, look at the link between human population size, history, and species richness, and show how the distribution of particular
species reflects the likely history of ornamental plantings. Results are used to assess whether past management actions have
been appropriately directed.
Two hundred and fifty-eight alien species have been recorded in the 36 tourist camps and staff villages. The number of staff
housed in villages explains much of the diversity of cultivated alien plant species. Older camps also tend to have more ornamental
alien plant species. However, the lack of a strong link between camp age and number of cultivated species suggests that ornamental
plants have been widely spread around the KNP by humans. We also show that increased camp activity (either size or age) has
led to more ornamental species, while, with the notable exception of Skukuza, camp activity has had a much smaller effect
on the number of noncultivated species. Noncultivated species tend to be naturally dispersed, as opposed to directly spread
by humans between camps.
Past management prioritized certain species on the basis of their potential to invade KNP and on the prevailing national legislation.
These species were removed manually and follow-up control was carried out. Once the priority species were deemed to be under
control, less invasive species were targeted. All alien species were removed from vacated houses, regardless of the potential
invasiveness of the species.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
882.
Jung Jin Park Anna Jorgensen Carys Swanwick Paul Selman 《Journal of Environmental Planning and Management》2008,51(5):679-699
This study explored the public perceptions of mobile telecommunications development – new landscape elements installed to deliver new technology – in a protected area. It examined: (1) the perceived landscape impacts of such development; (2) the importance attached to the socio-economic value of mobile telecommunications; and (3) the factors underlying the perceived landscape impacts of mobile telecommunications development. A postal questionnaire survey was conducted in the Peak District National Park, England with 420 respondents drawn from National Park residents and visitors, urban dwellers and members of environmental organisations. The study suggests that: (1) there was a prevailing antipathy towards the landscape impacts of mobile telecommunications development in the National Park; (2) apart from emergency uses, the other socio-economic benefits of mobile telecommunications technology were thought to be relatively unimportant in the National Park; and (3) rather than socio-demographic characteristics, it was respondents' understandings of protected areas' needs for the technology and potential health risks that had significant effects on the perceived landscape impacts. Overall, this study suggests that the significance of National Park landscapes is respected by the public, even when setalongside the convenience of modern technology, which has substantial implications for landscape planning and management in protected areas. 相似文献
883.
Krishna Prasad Vadrevu K. V.S. Badarinath Anuradha Eaturu 《Journal of Environmental Planning and Management》2008,51(6):817-832
Information on fires in different geographic regions of India is relatively scarce. This study quantifies spatial and temporal patterns in fire occurrences covering different states and districts in India. Two important scientific questions are answered in this study: (1) how are the fire events distributed across different geographical regions? (2) are there any specific districts where fire events clustered across space and time? To address these questions, Along Track Scanning Radiometer (ATSR) derived satellite fire counts from 1997–2006 were used and the datasets were analysed using spatial scan statistic. Spatial scan statistic provides a test statistic for most likely ‘hotspot’ spatial clusters, based on the likelihood ratio test and Monte Carlo simulation. Results from geographical analysis based on state boundaries suggested Maharastra state had the highest number of fires followed by Madhya Pradesh, Chattisgarh, Orissa, etc., during the 10-year period. Among the several districts, the spatial scan statistic identified the most likely cluster of fire events in Dausa, Karauli, Sawai Madhopur, Bharatpur and Alwar in addition to several other secondary clusters, with high statistical significance. These results are based on a large sample of cases, and they provide convincing evidence of spatial clustering of fire events in the Indian region. Results relating to hotspot areas of fire risk can guide policy makers towards the best management strategies for avoiding damages to forests, human life and personal property in the ‘hotspot’ districts. 相似文献
884.
Outdoor school environments are sites for play and physical activity for many children, and shortcomings within these environments are considered significant factors that contribute to children's inactive lifestyles and high levels of childhood obesity. This study explores the associations between the physical characteristics of schoolyards and the physical activity of third and fourth year students in five Turkish primary schools. Data were collected through multiple methods, including behavior mapping of student activities during recess, physical assessments of schoolyards, and interviews with students, teachers and administrations. The findings show similarities in the landscape features and physical qualities of schoolyards, particularly in the types of play and activities in which students engage. Results indicated that active students who walk to and from schools have lower body mass index (BMI) values than passive students, and students in schools with larger yards have lower BMI values. Most of the students prefer spacious and vegetated yards. A major concern is the crowdedness of the yards during recess that limit children's activity. Schoolyards with advanced landscape features are preferred more, and this in turn affects students’ positive satisfaction. Outdoor school environments have a correlation to health outcomes and should be designed to promote more activity. Improving the physical and landscape qualities of the public schoolyards should be the primary concern of the designers in order to increase awareness of natural environment and more important, increase the health of children. 相似文献
885.
886.
Annik Schnitzler Jean-Claude Génot Maurice Wintz Brack W. Hale 《Journal of Agricultural and Environmental Ethics》2008,21(5):423-436
This article discusses the ecological and cultural criteria underlying the management practices for protected areas in France.
It examines the evolution of French conservation from its roots in the 19th century, when it focused on the protection of
scenic landscapes, to current times when the focus is on the protection of biodiversity. However, biodiversity is often socially
defined and may not represent an ecologically sound objective for conservation. In particular, we question the current approach
to protecting a specific type of biodiversity that is at the basis of traditional landscape but does not value systems that
are left to develop naturally (i.e., without significant human intervention). We present several examples of current attempts
in France and Europe to managing traditional ecosystems and then discuss the values that exist in systems that develop naturally.
We feel the latter systems often have much to offer in terms of biodiversity as well as providing important sites for the
study of dynamic ecological communities in an ever-changing world. 相似文献
887.
Yazvenko SB McDonald TL Blokhin SA Johnson SR Melton HR Newcomer MW Nielson R Wainwright PW 《Environmental monitoring and assessment》2007,134(1-3):93-106
Exxon Neftegas Limited, as operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf
off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG) on behalf of the Sakhalin-1 consortium conducted a 3-D
seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary feeding area of the
endangered western gray whale (Eschrichtius robustus) is located in the vicinity of the seismic survey. This paper presents data to assess whether western gray whale bottom feeding
activity, as indicated by visible mud plumes, was affected by seismic operations. The mitigation and monitoring program associated
with the seismic survey included aerial surveys during 19 July–19 November 2001. These aerial surveys documented the local
and regional distribution, abundance, and bottom feeding activity of western gray whales. Data on gray whale feeding activity
before, during and after the seismic survey were collected, with the whales assumed to be feeding on the benthos if mud plumes
were observed on the surface. The data were used to assess the influence of seismic survey and other factors (including environmental)
on feeding activity of western gray whales. A stepwise multiple regression analysis failed to find a statistically significant
effect (α = 0.05) of the seismic survey on frequency of occurrence of mud plumes of western gray whales used as a proxy to evaluate
bottom feeding activity in Piltun feeding area. The regression indicated that transect number (a proxy for water depth, related
to distance from shore) and swell height (a proxy for sea state) were the only variables that had a significant effect on
frequency of whale mud plumes. It is concluded that the 2001 seismic survey had no measurable effect (α = 0.05) on bottom feeding activity of western gray whales off Sakhalin Island.
M.W. Newcomer, deceased 相似文献
888.
可持续发展理念下的地质环境承载力初步探讨 总被引:4,自引:1,他引:3
在环境承载力概念的基础上定义了地质环境承载力,讨论了地质环境承载力的内在涵义及特点,以城市地质环境为例,探讨了地质环境承载力评价的工作程序。 相似文献
889.
不同共代谢基质对白腐菌降解吲哚的作用研究 总被引:1,自引:0,他引:1
选用氨氮、苯酚和喹啉作为吲哚的共代谢基质,通过白腐菌BP对共基质体系的降解研究了白腐菌在秸秆滤出液培养基中对不同共基质体系的代谢过程,并进行了动力学分析,考察了不同共代谢基质物质对白腐菌漆酶分泌和吲哚降解的影响.结果显示,不同降解体系中的白腐菌都可去除99%以上的吲哚.充分的氮源可提高白腐菌的活性和漆酶酶活的峰值;共基质苯酚和喹啉可以增加白腐菌漆酶产量,为吲哚的降解提供较多的电子,同时苯酚和喹啉也能得到较高的去除.在秸秆滤出液中,白腐菌在pH为6~8之间对吲哚都具有较强的降解能力.吲哚在白腐菌的代谢过程中,可能首先在吡啶环的2和3位发生一步羰基化. 相似文献
890.