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211.
Managers need measurements and resource managers need the length/width of a variety of items including that of animals, logs,
streams, plant canopies, man-made objects, riparian habitat, vegetation patches and other things important in resource monitoring
and land inspection. These types of measurements can now be easily and accurately obtained from very large scale aerial (VLSA)
imagery having spatial resolutions as fine as 1 millimeter per pixel by using the three new software programs described here.
VLSA images have small fields of view and are used for intermittent sampling across extensive landscapes. Pixel-coverage among
images is influenced by small changes in airplane altitude above ground level (AGL) and orientation relative to the ground,
as well as by changes in topography. These factors affect the object-to-camera distance used for image-resolution calculations.
‘ImageMeasurement’ offers a user-friendly interface for accounting for pixel-coverage variation among images by utilizing
a database. ‘LaserLOG’ records and displays airplane altitude AGL measured from a high frequency laser rangefinder, and displays
the vertical velocity. ‘Merge’ sorts through large amounts of data generated by LaserLOG and matches precise airplane altitudes
with camera trigger times for input to the ImageMeasurement database. We discuss application of these tools, including error
estimates. We found measurements from aerial images (collection resolution: 5–26 mm/pixel as projected on the ground) using
ImageMeasurement, LaserLOG, and Merge, were accurate to centimeters with an error less than 10%. We recommend these software packages as a means for expanding
the utility of aerial image data. 相似文献
212.
Takanori Hino Ryuichi Agawa Youichi Moriya Minoru Nishida Yasuhiro Tsugita Takao Araki 《Journal of Material Cycles and Waste Management》2009,11(1):42-54
Waste printed circuit boards contain valuable metals such as Au, Pd, Ag, and Cu that can be reutilized and harmful elements
such as Pb, Br, and Cr that must be removed from the viewpoint of environmental conservation. In this research, we examined
a method that separates the materials from printed circuit boards contained in discarded personal computers. After cutting
the printed circuit boards to a size of 20 × 20 mm, they were heated at 873 K under an Ar atmosphere to remove organic resins
containing elements such as C, H, and N. After heat treatment, the printed circuit boards were crushed using a planetary ball
mill and the pulverized powders were filtered. The fraction with a granularity of greater than 250 μm was separated into magnetic
and nonmagnetic materials by a magnetic field. Because the fraction with a granularity of less than 250 μm contained 39 mass%
of C, it was heated at 1273 K in an atmosphere of 95% Ar and 5% O2 to allow carbon combustion to take place, followed by metal reduction processing at the same temperature in an atmosphere
of 97% Ar and 3% H2. The basicity of the resulting powder was adjusted and the powder was heated at 1773 K under an Ar atmosphere. The proposed
method separated the slag and metal, and 80% of the valuable metals contained in printed circuit boards could be collected. 相似文献
213.
Li Li Shixiao Yu Baoping Ren Ming Li Ruidong Wu Yongcheng Long 《Environmental science and pollution research international》2009,16(4):474-478
Background, aim, and scope The Yunnan snub-nosed monkey is one of the most endangered primates in the world. It is experiencing a range of ongoing threats
and the persisting effects of past disturbances. The prospects for this species are not very optimistic because habitat corridors
are severely damaged by logging, grazing, and mining. Each group of the monkeys in different areas is facing a unique variety
of threats. Based on genetic analysis, Rhinopithecus bieti should be separated into three management units for conservation, of which the Mt. Laojun management unit involves the most
endangered primates. Despite the fact that the vegetation on Mt. Laojun is in a relatively pristine state, only two groups
of monkeys, of a total of fewer than 300, survive in the area. With this paper, we aimed to address the capacity of the monkeys’
habitat at the study site and the possible reasons for the small populations.
Materials and methods Rapid ecological assessment based on a SPOT 5 image and field survey was used to simulate the vegetation of the whole area
based on reference ecological factors of the GIS system. The vegetation map of the site was thus derived from this simulation.
Based on the previous studies, the three vegetation types were identified as the suitable habitat of the monkeys. The confusion
matrix-based field GPS points were applied to analyze the precision of the habitat map. Based on the map of suitable habitat
of the monkeys, the utilization of the habitat and the carrying capacity were analyzed in the GIS.
Results The confusion matrix-based field GPS points were applied to the habitat analysis process, and it was found that the habitat
map was 81.3% precise. Then, with the current habitat map, we found that the mixed forest currently used by the monkeys is
only a very small fraction (2.65%) of the overall potential habitat of the population, while the dark conifer forest is 4.09%.
Discussion Poaching is the greatest short-term threat to this species, particularly in the southern range where local residents have
a strong tradition of hunting. Quite a few individual monkeys are still trapped accidentally due to the high density of traps.
These problems are hard to mitigate because it is difficult to enforce laws due to the extremely rugged terrain.
Conclusions The results show that there is a great ecological capacity of the area for the monkey’s survival and a great potential for
an expansion of the monkey population at the site. Based on the current population and its geographical range, it can be estimated
that the suitable habitat area defined by this study can support more monkeys, about many times the current population. Thus,
at least in the Mt. Laojun Area, poaching pressure is the main factor to be responsible for the low density of Yunnan snub-nosed
monkeys instead of habitat alteration.
Recommendations and perspectives Based on these results, some suggestions relating to conservation can be made: Focus conservation efforts on the current distribution
area of the monkeys and create a 20 km buffer zone; design a long-term plan for the suitable habitat outside the buffer zone
to set up a wildlife corridor in the long run; establish an association for the local hunters exploiting, their knowledge
on the animals to promote monkey conservation and stop poaching. Also, the map derived from the study helps managers to allocate
conservation resources more efficiently and enhances the overall outcomes of conservation measures. 相似文献
214.
Manfred Fehr 《Environment, Development and Sustainability》2009,11(2):319-328
As biodegradable material represents approximately 70% of household waste in Brazil, any strategy to divert appreciable waste
quantities from landfills of necessity has to include valorization and recycling of this material. A societal change of attitude
is required to perceive this challenge. Experiments in an urban apartment building are described that produced this change
of attitude with a success factor of 80%. Divided waste collection was implemented that separated at the source biodegradable
from inert material. Correct collection, handling and display procedures were established. Composting of biodegradable material
was carried out under the rooftop of the building as an alternative to using it as animal feed. Half of the inert material
entered the reverse logistics chain and was also diverted from the landfill. Waste related material flow through the building
is completely quantified, food intake and waste production are related, diversion of both biodegradable and inert waste components
from the landfill is measured and the composting process is described. The landfill diversion stands at 61%, mass reduction
through the composting process is 80% and matured compost is returned to residents for use in flower cages. The system has
been operational for two years and stands out as a precedent in successful decentralized household waste management supported
by material flow analysis.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue. 相似文献
215.
丹江口水库作为南水北调中线工程水源地,其库区的土地利用/覆被变化可能带来的生态环境效应备受关注。以2000和2004年的多源遥感影像为主要数据源,解译生成土地分类数据,对研究区内土地利用变化总体特征、速度、景观优势度变化以及景观生态效应进行了分析。结果显示:库区在这4年间土地利用整体结构上没有显著改变,但是耕地、建设用地增加,林地、未利用地减少。景观多样性指数及景观均匀性指数呈下降趋势,说明景观异质程度下降,景观类型有向单一化及非均衡化方向发展的趋势。林地减少加剧库区的水土流失,导致库区的生态环境质量下降,应采取措施促使库区经济与生态环境良性地协调发展。 相似文献
216.
一种基于混沌和魔方的数字图像置乱算法 总被引:2,自引:2,他引:0
在现有数字图像置乱算法的基础上,分别分析了这些算法存在的不足,详细介绍了混沌序列及其优点。在介绍魔方玩法的基础上,指出可以把对魔方的初始置乱理解成加密过程,并分析魔方的加密原理在数字图像置乱中应用的可能性。并设计了一种结合混沌和魔方优点的数字图像置乱算法。该方法将图像的行列和对角线定义成魔方变换的旋转面,将对魔方的旋转定义成旋转面的循环移动。置乱过程先根据密钥产生混沌序列,再由混沌序列控制魔方变换进行图像置乱。通过与其他算法的实验对比,表明该算法有较好的图像置乱效果,达到了对图像进行置乱的目的。分析表明,该算法的时间复杂度较低,安全性较高,满足实际的应用需要。 相似文献
217.
伊犁河谷生态旅游形象定位及产品设计 总被引:1,自引:0,他引:1
生态旅游资源是生态旅游开发的基础,但拥有旅游资源并不等于就拥有旅游产品,旅游资源要成为旅游产品,还必须根据市场需求进行形象设计、加工和再创造。伊犁河谷具有得天独厚的生态环境和世所罕见的生物多样性特征,是开发生态旅游产品、发展生态旅游的理想之地。以伊犁河谷生态旅游源为基础,塑造伊犁河谷生态旅游形象,设计开发特色生态旅游产品。 相似文献
218.
The Leaching Characteristics of Chromite ore Processing Residue 总被引:1,自引:0,他引:1
D. Deakin L.J. West D.I. Stewart B.W.D. Yardley 《Environmental geochemistry and health》2001,23(3):201-206
219.
环境突发事件应急处理要做到“万无一失”,必须动员社会上的一切力量,现有的环保系统处理这一系统工程困难较大。笔者根据多年实践经验,分析了应急处理的系统性,提出了建立环境突发事件应急处理系统的设想,探索了其运行机制。 相似文献
220.
胶态水合二氧化锰絮凝粒子的结构形貌及其混凝机理 总被引:4,自引:0,他引:4
采用透射电镜技术观察了胶态水合二氧化锰絮凝粒子的结构形貌并采用Zeta电位测定仪对粒子的荷电特征进行了研究;利用红外光谱、XRD等技术对粒子的界面性质进行了表征;通过混凝试验考察了KMnO4 还原法制备的水合二氧化锰胶体对原水的混凝性能并探讨了混凝机理.结果表明,胶态水合二氧化锰粒子在去离子水和原水中荷负电,在去离子水中,粒子直径为10 nm并形成网状结构,有利于发挥吸附架桥作用;粒子具有丰富的表面羟基,比表面积为151.422 m2/g,为δ-MnO2,表现出优良的吸附污染物的界面特性;较低投量的胶态水合二氧化锰表现出对原水的优良混凝效能和去除有机微污染的效能. 相似文献