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1.
Here, we describe a methodology for quantifying the spawning habitat of īnanga (Galaxias maculatus), a protected native fish species. Our approach is demonstrated with a survey of the Heathcote/ōpāwaho following the Canterbury earthquakes that produced unexpected findings. Spawning habitat was detected over a 2.5?km reach and the area occupied by spawning sites (75m2) was much larger than in previous records (ca.?21m2). Sites dominated by the invasive Phalaris arundinaceae were found to support high egg numbers. Spawning has not previously been recorded on this species and it is identified in the literature as a threat to spawning habitat. Considerable spatio-temporal variation was also detected in the location of spawning sites and pattern of egg production. Together, these aspects illustrate the need for a comprehensive survey methodology to reliably quantify spawning habitat. The Heathcote/ōpāwaho example shows the utility of our census approach for achieving this, and supporting habitat conservation objectives.  相似文献   
2.
中国1∶100万景观生态制图设计   总被引:5,自引:0,他引:5  
中国1∶100万景观生态图系借鉴国内外传统景观制图方法和制图规范,在遥感、地理信息系统先进技术的支持下,设计研制其制图方法、制图内容、样图和技术流程,同时提出初步的景观分类系统,为今后编制中国1∶100万景观生态图奠定基础。  相似文献   
3.
This paper considers the present state of mathematical geology. Three directions are recognized: applied, theoretical, and mathematical. Applied mathematical geology includes formal use of mathematics to solve problems and computer processing of data. Success is achieved by a correspondence of mathematical methods used to the nature of geological data. This correspondence can be demonstrated by purely mathematical means. Theoretical mathematical geology uses mathematics as a language of geology; however, a number of methodological problems must be solved: formalization of initial geological concepts and creation of a strict conceptual basis, substantiation of initial principles of mathematical simulation, creation of theoretical geological models, problems of elementary and coincidence in geology, and methodological substantiations of possibilities of any mathematical model to approximate geological models. The essense and significance of these problems are considered. The main task of mathematical geology is to prove its correspondence to the nature of the geological objects studied, geological data obtained, and geological problems solvable. Finally, the main problems of mathematical geology are not so much mathematical as geological and methodological.  相似文献   
4.
A methodology for the characterization of deep carbonate aquifers has been developed and applied to El Maestrazgo Jurassic aquifer in Castellón, Spain. Characterization of these aquifer formations, located at more than 300 m deep, consisted of a previous phase of compilation, analysis and synthesis of the existing information about the area, followed by a coordinated combination of different speciality studies: geology, stratigraphy, structural analysis, hydrogeology, hydrochemistry, geophysics and remote sensing. Geological studies included geological mapping, definition of stratigraphical units and facies and structural analysis. The aim of the hydrogeology study was to define aquifer formations, recharge area, aquifer points inventory and groundwater flow directions for the establishment of piezometric and water quality observation nets. Special techniques were applied, like thermal infrared aerial images and the evaluation of submarine groundwater discharge by means of natural radium isotopes. Hydrochemical techniques, including majority elements characterization and stable isotopes (18O, 2H and 3H) determination, allowed classifying hydrochemical facies and establishing a renewal pattern for water within the system. Geophysics was useful in determining the aquifer geometry, the features of the basement and the petrophysical characteristics of the geological formations. Preliminary results show an important tectonic complexity and the possibilities for groundwater uses in the area of study.  相似文献   
5.
6.
We report on an objective methodology, referred to as intrinsic sample methodology, for the delineation of exploration target areas or resource areas for assessment. Important features of the methodology include (1) identification of recognition criteria for critical genetic factors, (2) synthesis of new variables from enhanced geodata, (3) estimation of logit probability models, and (4) cutting of estimated logit probabilities to delineate exploration targets or resource areas. The methodology is demonstrated on the Walker Lake quadrangle of Nevada and California.  相似文献   
7.
Kriging with imprecise (fuzzy) variograms. I: Theory   总被引:2,自引:0,他引:2  
Imprecise variogram parameters are modeled with fuzzy set theory. The fit of a variogram model to experimental variograms is often subjective. The accuracy of the fit is modeled with imprecise variogram parameters. Measurement data often are insufficient to create good experimental variograms. In this case, prior knowledge and experience can contribute to determination of the variogram model parameters. A methodology for kriging with imprecise variogram parameters is developed. Both kriged values and estimation variances are calculated as fuzzy numbers and characterized by their membership functions. Besides estimation variance, the membership functions are used to create another uncertainty measure. This measure depends on both homogeneity and configuration of the data.  相似文献   
8.
年度考核现状分析及改进对策   总被引:1,自引:0,他引:1  
通过对现行年度考核体系的现状分析,着重探讨如何改进考核办法,充实考核内容,建立科学有效的考评体系,提高考核效率,充分发挥年度考核结果在干部选拔、薪酬福利、培训开发、人员招聘和配置、个人职业生涯发展中的重大作用。  相似文献   
9.
从近年来我国地层学的可喜进展谈地层学方法论   总被引:1,自引:0,他引:1  
梅冥相 《地层学杂志》2002,26(2):139-145,150
“乐平统”作为国际二叠系年代地层系统的最上一个统的全球对比标准 ,是我国学者金玉研究员为首的研究集体多年艰辛研究的结果 ;几乎同时 ,以陈旭研究员为首的科研集体以详尽的资料和全面系统的工作 ,在我国浙江黄泥塘剖面建立了中奥陶统达瑞威尔阶的全球层型剖面点——中国第一个“金钉子”剖面。这两项成就 ,是我国学者在上一世纪对地层学的显著贡献之一 ,从他们精雕细刻的剖面资料和详尽系统的研究成果中 ,可以研读出对“地层时代对比”这一博大精深的理论课题的工作方法 ,由此而诱发出对地层学方法论的探讨 ,从而对某些下结论还为时过早的问题进行必要的评述。  相似文献   
10.
新时期我国区域经济地理学发展问题初探   总被引:4,自引:0,他引:4  
我国新时期的区域经济地理学在取得全面发展的同时,在理论体系,研究方法和实践领域等方面还需要进一步的发展,文章根据学习和实践区域经济地理学的体会,初步提出基础理论和应用理论,思维方法和技术方法等方面发展见解,并指出区域创新系统和国际经济技术合作等学科应注意拓展的重要实践领域,最后提出我国区域经济地理学科发展的建议。  相似文献   
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