人工冻土破碎块度分布的分形性质

从分形几何的观点出发，通过对冻土模型的爆破试验，着重对试样爆后破块块度分析进行了统计分析。结果表明，冻土爆后块度分布是个分形，分形维数不仅是反映冻土破碎程度恰当的统计特征量，而且与试样冻结温度密切相关，还探讨了分维值与冻土抗压强度的关系。     

多重分形与地球化学元素的分布规律

为进一步探讨用分形与多重分形的方法研究地球化学场中元素的分布规律的重要意义，运用Q-Q图和直方图探讨了元素的空间分布规律，随后运用多重分形矩方法研究了安徽省长江以南以北各约22000km^2和18100km^2区域内5489个和4524个水系沉积物样品中14种元素的分形分布规律。结果表明，金属地球化学场元素在空间上的分布并不是简单的正态或对数正态分布，而四连续多重分形分布，其α-f(α)曲线上凸且连续，拥有主要大型矿床的安徽江南地区α-f(α)曲线的开口明显大于成矿相对较弱的安徽江北地区。元素的多重分形谱函数的形态特征对区域成矿潜力研究将具有一定的指示意义。     

多维分形理论和地球化学元素分布规律

多维分形模型不仅采用常规的低阶矩统计, 而且采用高阶矩统计对多维分形分布进行度量, 从而能较细致地刻划正常值以及异常值.地球化学元素的正常值往往服从统计学中的大数定量, 即满足正态分布或对数正态分布, 然而异常值会服从分形分布(Preato).介绍了多维分形领域中的最新发展以及在地球化学研究中特别是研究超常元素空间分布和富集规律中的应用.结果表明, 通常的统计方法只对应于多维分形围绕均值周围的局部特征.为了有效地研究异常值的分布和富集规律, 建议采用高阶矩统计方法和多维分形方法, 并给出了两种分析地球化学元素, 并突出异常值贡献的方法.这些方法不仅可应用于研究微量元素的空间分布和富集规律, 而且可以区分地球化学背景与矿化有关的异常值.还介绍了该方法在对加拿大B.C.省西北部Mitchell-Sulphurets地区金铜矿化蚀变带研究中的应用.      

结构面对岩体爆破块度分布影响的分形探讨

在前人研究成果的基础上，应用分形几何理论探讨了结构面对岩体爆破块度分布影响的分形规律，得出了几点有益的结论。     

贵州洞穴螺类的物种多样性及分布初步研究

2001年1月至2002年8月对贵州的龙洞、和尚洞、竹林洞及织金洞等50余个洞穴内的螺类进行了调查,共采集标本1306号,经鉴定和分类,隶属1纲2目15科108种, 其中有4个新种.不难看出,贵州洞穴螺类的物种丰富度较高,并具有从有光带到弱光带呈下降趋势;从物种的丰度来看,在有光带最高,弱光带和黑暗带则无明显的差异. 优势种不明显.从水平分布看, 分布的种类和数量最多的均是有光带; 从空间分布看, 主要分布于洞底. 此外, 还对螺类适应洞穴生活的特征及保护作了初步分析.     

基于分形理论的浙江省地质灾害分布特征与影响因素分析

在浙江省地质灾害空间分布特征研究中引入了多重分形方法,基于分形理论研究地质灾害分布的影响因素。研究结果表明：浙江省地质灾害空间分布具有明显的分形特征,西北和东南地区发育较强烈;浙江省地质灾害空间分布与水系分布、降水量、地形坡度、坡高、地层岩性、道路分布及地形地貌有关,其中在降雨量为2 232～2 565 mm、坡度为25°～35°范围内、坡高为500～1 000 m范围内和侏罗系地层范围内,崩塌、滑坡、泥石流灾害发育明显,在山地地形范围内地质灾害易发生。浙江省的道路分布中,省道分布对地质灾害发育的影响比较大;浙江省钱塘江水系和瓯江水系比较复杂,且对地质灾害发育的影响比较大。研究成果进一步明确了浙江省地质灾害分布特征及主要影响因素影响规律,对灾害防治开展具有指导参考意义。     

贵州水城仲河剖面二叠纪-三叠纪之交底栖群落的物种多样性与功能多样性转变

为了定量化恢复晚二叠世末期生物大灭绝对底栖群落的物种多样性和功能多样性的影响,对浅海碎屑岩台地相区的贵州水城仲河剖面开展宏体化石采集和分析,识别和划分古群落,选择优势度、香农指数、均匀度等代表物种多样性指数,生态功能群数量和功能均匀度代表功能多样性指数. 共采集1 340枚化石标本,经鉴定得到30属33种,其中双壳类可归纳为两个生物带:晚二叠世长兴期的Hunanopecten exilis顶峰带和早三叠世Griesbachian早期的Pteria ussurica variabilis顶峰带. 根据化石属种的地层分布、保存状况,结合聚类分析方法识别出3个古群落:Astartella obliqua-Tethyochonetes quadrata群落、Pteria ussurica variabilis-Claraia wangi群落和Pteria ussurica variabilis-Unionites canalensis群落. 自晚二叠世长兴期末期至早三叠世Griesbachian早期,古群落的优势度上升、香农指数降低、均匀度下降,功能群丰富度降低,功能均匀度上升,这指示晚二叠世末生物大灭绝对浅海碎屑岩相区的底栖群落的组成和功能均有显著的破坏. 此外,结合华南浅海和深海相区的古群落数据,发现底栖群落的物种多样性指数和功能多样性指数在晚二叠世末生物大灭绝中均遭受损失,但是浅海底栖群落受影响较高.      

矿床储量规模分布的分形模型及其分维的数理分析

矿床储量规模预测在矿产勘查和评价中占有十分重要的位置,而其预测的最主要手段是建立矿床储量规模分布的数学模型.根据矿床储量的统计自相似性,应用概率统计方法建立了矿床储量规模的分形模型.同时,通过模型及其分维值的数理分析,得出不同分维值的地学解释,讨论了分维的线性与非线性最小二乘回归估计法.     

含水状态下弱风化泥质粉砂岩冲击破碎的分形规律研究

水对岩石的物理力学性质影响较大,研究不同含水状态下岩石受冲击荷载后破碎物的分形规律具有较强的现实意义。借助于分离式霍普金森杆（SHPB）实验装置,开展不同含水状态的泥质粉砂岩的冲击试验,然后对破碎物的块度分布进行深入分析,并基于尺寸-频率分析方法,重点对破碎物颗粒粒径分布的分形规律进行探讨。结果表明,随着加载速率的提高,泥质粉砂岩冲击破碎物单块体积普遍减小,残留碎块的数量越多,破碎的程度也越高,此时分形维数越小;含水率越大,小颗粒比例越大,岩样破碎程度越高,饱水状态岩样的分形维数较其他两种状态大,天然含水状态和自然吸水状态岩样冲击破碎的分形维数较为接近;当冲击速度较大时其将成为影响分形维数的主要因素,含水率的影响相对较小。     

基于连续分形理论的土壤非饱和水力传导度的研究

土壤的孔隙是具有连续分形性质的物理结构,根据土壤孔隙分形结构建立了非饱和水力传导度模型。模型包括综合系数、分形维数和临界体积比3个参数,综合系数为不同土壤基质势对应的非饱和水力传导度与饱和传导度之间的水力联系,与土壤质地有关;分形维数反映土壤孔隙结构对于非饱和水力传导度的作用,土壤不同尺寸孔隙之间的连通性则通过临界体积加以描述。模型具有较为明确的物理解释。将模型应用于5种不同土壤的结果表明,所提出的非饱和水力传导度模型具有较好的模拟效果。     

Analyzing Fractal Property of Species Abundance Distribution in A Community

The study of Apecies Abundance Distribution (SAD) is the key of understanding what determines species diversity. The theoretical exploration of SAD relates to the maintenance and conservation of biodiversity, and more importantly, it is conducive to clarifying complicated relationship among species and the distribution of matter and energy in a community. The research on SAD began in the 1930s, and there are so many kinds of theoretical models of SAD that can fit actual data, such as geometric-series model, log-series model, log-normal model, broken-stick model and so on. However, despite this, these models are often restrictive in their hypotheses and difficult to fit by natural communities. Especially, there is not always a good fit to the community that only has a few species. Thus, Frontier firstly introduced a family of models termed the Zipf-Mandelbrot model. This model is unrestrictive and easily fit by different natural community. Accordingly, this paper reviewed its origin, hypothesis, construction, problems and ecological signification of parameters to promote the research of SAD and the determination of species diversity.     

Indicator Pattern Combination for Mineral Resource Potential Mapping with the General C-F Model

As an uncertain reasoning model, the general C-F model was originally developed for processing the uncertainties of rule-based knowledge in the field of artificial intelligence. In this model, certainty factors and combined certainty factors are defined and used for expressing the strengths of knowledge rules and knowledge rule combinations, respectively. The certainty factor can reflect the believable degree of inferring hypothesis on the basis of a proof. Similarly, the combined certainty factor can reflect the believable degree of inferring hypothesis on the basis of the proof combination. It is a function of the related certainty factors and can be determined through combining the certainty factors via the combining rule of the general C-F model. In this paper, the general C-F model has been successfully applied to mineral resource potential mapping. We call this model as the applied form of the general C-F model. In this applied form, the certainty factor is applied to expressing the believable degree of inferring mineral occurrence on the basis of one of the map pattern states associated with the mineral occurrence. Correspondingly, the combined certainty factor is applied to expressing the believable degree of inferring the mineral occurrence on the basis of the map pattern state association. And it is also applied to expressing mineral resource potentials in the mineral resource potential mapping. In the current form, the first step in implementing the general C-F model is to estimate a pair of certainty factors for each map pattern under combination. The next step is to determine the combined certainty factor for the map pattern states coexisting in each locality of the mapping area. The last step is to generate the combined-certainty-factor raster map or the combined-certainty-factor contour map in order to select mineral resource targets. The applied form of the general C-F model is demonstrated on a case study to select mineral resource targets. The experimental results manifest that the model can be compared with the weights-of-evidence model in the effectiveness of mineral resource target selection.     

Land Use and Salinity Drive Changes in SAV Abundance and Community Composition

Conserving and restoring submerged aquatic vegetation (SAV) are key management goals for estuaries worldwide because SAV integrates many aspects of water quality and provides a wide range of ecosystem services. Management strategies are typically focused on aggregated abundance of several SAV species, because species cannot be easily distinguished in remotely sensed data. Human land use and shoreline alteration have been shown to negatively impact SAV abundance, but the effects have varied with study, spatial scale, and location. The differences in reported effects may be partly due to the focus on abundance, which overlooks within-community and among-community dynamics that generate total SAV abundance. We analyzed long-term SAV aerial survey data (1984–2009) and ground observations of community composition (1984–2012) in subestuaries of Chesapeake Bay to integrate variations in abundance with differences in community composition. We identified five communities (mixed freshwater, milfoil-Zannichellia, mixed mesohaline, Zannichellia, and Ruppia-Zostera). Temporal variations in SAV abundance were more strongly related to community identity than to terrestrial stressors, and responses to stressors differed among communities and among species. In one fifth of the subestuaries, the community identity changed during the study, and the probability of such a change was positively related to the prevalence of riprapped shoreline in the subestuary. Mixed freshwater communities had the highest rates of recovery, and this may have been driven by Hydrilla verticillata, which was the single best predictor of SAV recovery rate. Additional species-specific and community-specific research will likely yield better understanding of the factors affecting community identity and SAV abundance, more accurate predictive models, and more effective management strategies.     

A Fractal Simulation Method for Simulating the Resource Abundance of Oil and Gas and Its Application

Mathematical Geosciences - In this study, a fractal simulation method for simulating resource abundance is proposed based on the evaluation results of the exploration risk and prediction technology...     

Abundance and Community Structure of Airborne Microorganisms over the Ocean and Their Influencing Mechanisms

Airborne microorganisms play an essential role in the microbial propagation and maintenance of the ecosystem diversity, and also significantly affect the climate by acting as effective Ice Nucleus (IN) and Cloud Condensation Nuclei (CCN). The ocean is a vital source and destination for airborne microbes. Nevertheless, little information has been obtained on the distribution of abundance and diversity of airborne microorganisms over the ocean. This paper systematically reviewed the abundance, size distribution, and community structure of airborne microorganisms over the ocean, as well as various environmental and meteorological factors that control the distribution of microbes in marine aerosols. The commonly used methods for detecting airborne microorganisms and their development prospects were also discussed. We pointed out that sampling and detection of extremely low concentration microorganisms in marine aerosols are key problems to be solved in this field, and future research directions include the increase of the cruising observation in open oceans and combination of advanced molecular techniques and other traditional methods. This paper provides extensive and crucial information for subsequently in-depth research on airborne microorganisms over the ocean, revealing their sources, activities, climate and ecological effects.     

福建地壳各岩类铜元素丰度及铜的矿源层（岩）讨论

根据福建省最新岩石测量成果得出的各岩类铜元素丰度,讨论和初步确定了福建铜的矿源层（岩）。提出可按照丰度值高低,铜的初始赋存状态与被解离的难易,有无矿床（点）及具找矿意义的异常产出这３项因素,进一步将矿源层（岩）划分为较可靠的、可能的和潜在的３个级别。     

北京顺平岩溶水系统富水性分析

本文在充分收集北京顺平岩溶水系统各种勘探资料的基础上,以施工的17眼探采结合井的钻探成井、抽水试验为主,结合岩屑鉴定数据等资料,查明了顺平地区主要含水岩组岩溶裂隙发育规律,分析了岩溶地下水富水性特征。该区主要为长城系高于庄组、蓟县系雾迷山组、寒武系和奥陶系灰岩含水层,单井涌水量最大可达10780 m3/d,最小4464m3/d。圈定了两处岩溶水源地靶区,分别位于北小营—杨镇—北务一带和马坊—东高村一带,为后续该区域岩溶水的合理开发和保护提供科学支撑。     

Nekton Communities in Hawaiian Coastal Wetlands: The Distribution and Abundance of Introduced Fish Species

Nekton communities were sampled from 38 Hawaiian coastal wetlands from 2007 to 2009 using lift nets, seines, and throw nets in an attempt to increase our understanding of the nekton assemblages that utilize these poorly studied ecosystems. Nekton were dominated by exotic species, primarily poeciliids (Gambusia affinis, Poecilia spp.) and tilapia. These fish were present in 50–85% of wetlands sampled; densities were up to 15 times greater than native species. High densities of exotic fish were generally found in isolated wetlands with no connection to the ocean, were often the only nekton present, were positively correlated with surface water total dissolved nitrogen, and were negatively correlated with native species richness. Native species were present in wetlands with complete or partial connection to the ocean. Additional studies are needed to document exotic fish impacts on native fish and bird habitat and whether native fish communities can contribute to invasion resistance of coastal wetlands. Future wetland restoration should include exotic fish eradication, maintenance of hydrological connection to the ocean, or programs to prevent future introductions in order to create wetlands that support native-dominated nekton communities.     

Spatial Analysis on Gold Mineralization in Southwest Saqqez Using Point Pattern,Fry and Fractal Analyses

Geotectonics - The Baneh- Saqqez zone is part of the Sanandaj‒Sirjan Zone, northwest of Iran. Generally, this zone is recognized as a gold bearing zone, and the mineralization in it is...