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1.
柳树沟磷矿开工时技术力量十分薄弱,以自己培养为主.广泛争取设计院等单位支持.基建工程严格按设计施工,并且建立健全各项规章制度,实行科学管理,安全生产文明生产,扩大生产规模,已由年产9万t扩大到20万t,企业经济效益、社会效益十分显著,成为乡镇矿山典范,磷矿企业的标兵.  相似文献   
2.
对青岛市3个村镇的103位村镇居民进行了环境意识调查,调查结果采用均值赋值法进行分析,发现居民对环境知识的实际知晓率不高,且获得环保信息的渠道相对单一,对环保的重要性、紧迫性认识较高、责任感较强,对污水处理有积极的态度,并有71%的被调查者愿意缴纳不超过10元/(月·户)的污水处理费用;被调查居民认为调查表中所列各项污染原因与本村的环境污染关系不大.  相似文献   
3.
Release of the antiaggregation pheromone, verbenone, at 3.8 mg/ day from a concentrated source within a multiple-funnel trap completely inhibited response by the mountain pine beetle (MPB),Dendroctonus ponderosae Hopkins, to attractive semiochemical lures. When aerial applications were simulated and verbenone was released at the same rate from beads lying in a 2×2-m area on the forest floor 15–35 cm below a trap, the response of the MPB was inhibited by only 50%. This reduced inhibition may be explained in part by the photoisomerism of verbenone. When exposed to full sunlight on two occasions, the times required for 50% of verbenone vapors to be converted to chrysanthenone were 75 and 100 min, respectively. Trap and tree-baiting experiments indicated no biological activity of chrysanthenone. Rapid photoisomerization could reduce the concentration of verbenone below biologically active levels and would allow the MPB to colonize trees close to already occupied hosts, contributing to the characteristic clumped distribution of MPB attack. The rate of verbenone photoisomerization may vary according to geographic location, stand elevation and density, and should be considered before verbenone is applied to control the MPB and other bark beetles.  相似文献   
4.
受暴雨洪水与滑坡、泥石流灾害的影响,山区河流床沙多为宽级配卵砾石泥沙,甚至出现较多的漂石,从而影响近底水流结构与推移质输移特性。基于野外漂石河流的调查,通过概化试验,探讨了漂石颗粒对河床冲淤的影响;对比分析了不同水沙条件下漂石对推移质输沙率过程的影响;根据床面粗化程度与漂石状态相异的两种类型对比试验,探讨了漂石对不同水沙条件下推移质输沙率的影响程度。初步表明:随着漂石颗粒相对暴露度(D/h,漂石等效粒径与平均水深之比)的减少,漂石对其尾部区域水流的混掺越加突出,从而对河床的冲刷能力变大;根据本试验采用的水沙参数,漂石对推移质输沙率的扩大效应为几倍至十几倍。  相似文献   
5.
以古民居的分布与发展演变为变量参数所形成的古村落拓扑图,通过对Lebesgue测度计算形成几何拟合数值曲线,在引入优美图优美标号的基础上,形成对村落优美度η的勒贝格测度值,在古村落发育(时间增长)过程中,η值是单调变化的。以徽州地区存在1000年古村落google卫星图像为基础,结合历史文献获得不同年代民居拓扑图,依据上述方法对村落拓扑中优美图进行统计量化,定义出村落优美度值η。结论认为η介于8000左右时,村落民居年代人文分布丰富;而低于6000时村落民居数量发展上升,但人文资料零乱;在700年左右的村落中,η值稳定在9600附近,呈现出古村落的明显拓扑特征。通过村落优美度按年代变化的η值曲线,对村落的(年代)演变做了分析。  相似文献   
6.
建设生态流域、协调流域生态环境保护与社会经济发展间的关系已成为当前流域研究的重点.对生态流域的概念及内涵进行了探讨,阐述了生态城市和生态乡村建设示范的规划目标,提出开展生态流域建设应重点开展流域分区与保护、城市群发展规划、生态产业规划、人工系统结构与功能调整四个方面的研究,以流域人工系统物质流和能量流的生态化为核心,深...  相似文献   
7.
Mountain pine beetle (Dendroctonus ponderosae Hopkins) is the most destructive insect infesting mature pine forests in North America and has devastated millions of hectares of forest in western Canada. Past studies have demonstrated the use of multispectral imagery for remote identification and mapping of visible or red attack damage in forests. This study aims to detect pre-visual or green attack damage in lodgepole pine needles by means of hyperspectral measurements, particularly via continuous wavelet analysis. Field measurements of lodgepole pine stands were conducted at two sites located northwest of Edmonton, Alberta, Canada. In June and August of 2007, reflectance spectra (350-2500 nm) were collected for 16 pairs of trees. Each of the 16 tree pairs included one control tree (healthy), and one stressed tree (girdled to simulate the effects of beetle infestation). In addition, during the period of June through October 2008, spectra were collected from 15 pairs of control- and beetle-infested trees. Spectra derived from these 31 tree pairs were subjected to a continuous wavelet transform, generating a scalogram that compiles the wavelet power as a function of wavelength location and scale of decomposition. Linear relationships were then explored between the wavelet scalograms and chemical properties or class labels (control and non-control) of the sample populations in order to isolate the most useful distinguishing spectral features that related to infested or girdled trees vs. control trees.A deficit in water content is observed in infested trees while an additional deficit in chlorophyll content is seen for girdled trees. The measurable water deficit of infested and girdled tree samples was detectable from the wavelet analysis of the reflectance spectra providing a novel method for the detection of green attack. The spectral features distinguishing control and infested trees are predominantly located between 950 and 1390 nm from scales 1 to 8. Of those, five features between 1318 to 1322 nm at scale 7 are consistently found in the July and August 2008 datasets. These features are located at longer wavelengths than those investigated in previous studies (below 1100 nm) and provide new insights into the potential remote detection of green attack. Spectral features that distinguish control and girdled trees were mostly observed between 1550 and 2370 nm from scales 1 to 5. The differing response of girdled and infested trees appears to indicate that the girdling process does not provide a perfect simulation of the effects caused by beetle infestation.It remains to be determined if the location of the 1318-1322 nm features, near the edge of a strong atmospheric water absorption band, will be sufficiently separable for use in airborne detection of green attack. A plot comparing needle water content and wavelet power at 1320 nm reveals considerable overlap between data derived from both infested and control samples, though the groups are statistically separable. This obstacle may preclude a high accuracy separation of healthy and infected single individuals, but establishing threshold identification levels may provide an economical, efficient and expeditious method for discriminating between healthy and infested tree populations.  相似文献   
8.
Topography and accuracy of image geometric registration significantly affect the quality of satellite data, since pixels are displaced depending on surface elevation and viewing geometry. This effect should be corrected for through the process of accurate image navigation and orthorectification in order to meet the geolocation accuracy for systematic observations specified by the Global Climate Observing System (GCOS) requirements for satellite climate data records. We investigated the impact of orthorectification on the accuracy of maximum Normalized Difference Vegetation Index (NDVI) composite data for a mountain region in north-western Canada at various spatial resolutions (1 km, 4 km, 5 km, and 8 km). Data from AVHRR on board NOAA-11 (1989 and 1990) and NOAA-16 (2001, 2002, and 2003) processed using a system called CAPS (Canadian AVHRR Processing System) for the month of August were considered. Results demonstrate the significant impact of orthorectification on the quality of composite NDVI data in mountainous terrain. Differences between orthorectified and non-orthorectified NDVI composites (ΔNDVI) adopted both large positive and negative values, with the 1% and 99% percentiles of ΔNDVI at 1 km resolution spanning values between − 0.16 < ΔNDVI < 0.09. Differences were generally reduced to smaller numbers for coarser resolution data, but systematic positive biases for non-orthorectified composites were obtained at all spatial resolutions, ranging from 0.02 (1 km) to 0.004 (8 km). Analyzing the power spectra of maximum NDVI composites at 1 km resolution, large differences between orthorectified and non-orthorectified AVHRR data were identified at spatial scales between 4 km and 10 km. Validation of NOAA-16 AVHRR NDVI with MODIS NDVI composites revealed higher correlation coefficients (by up to 0.1) for orthorectified composites relative to the non-orthorectified case. Uncertainties due to the AVHRR Global Area Coverage (GAC) sampling scheme introduce an average positive bias of 0.02 ± 0.03 at maximum NDVI composite level that translates into an average relative bias of 10.6% ± 19.1 for sparsely vegetated mountain regions. This can at least partially explain the systematic average positive biases we observed relative to our results in AVHRR GAC-based composites from the Global Inventory Modeling and Mapping Studies (GIMMS) and Polar Pathfinder (PPF) datasets (0.19 and 0.05, respectively). With regard to the generation of AVHRR long-term climate data records, results suggest that orthorectification should be an integral part of AVHRR pre-processing, since neglecting the terrain displacement effect may lead to important biases and additional noise in time series at various spatial scales.  相似文献   
9.
超高密度电法和激电法在河北某地找水实例分析   总被引:1,自引:1,他引:0  
通过介绍由澳大利亚引进的全新超高密度电法反演系统对河北省行唐县几个村庄的地下水勘查实例,对新兴的超高密度电法与传统的大功率激电测深法相结合的方式在太行山灰岩地区基岩水勘查的应用进行了可行性分析。高密度电法工作效率高、探测速度快,而大功率激电测深法探测精度高。二者有机结合,既可以提高工作效率、又可以互相印证,是一种很好的综合物探地下水勘查模式。通过平行布置电阻率测量剖面的工作方式很好的把控了破碎构造的走向,圈定了富水异常区,并最终取得了很好的勘探效果,实践证明该电法组合的勘探方式在同类地区中进行地下水勘查是很有推广价值的。  相似文献   
10.
建筑是对人类历史与文明的反映,一个国家的建筑史就是一个国家文明的发展史。与西方国家相比我国存世的古建筑资源相对贫乏。景宁县周边村落的这些古老的建筑是我国存世不多的古建筑其中的一部分,如何去研究开发它们,保护好它们,让它们能继续地存活下来,需要我们去努力。  相似文献   
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