基于IKONOS的黄河三角洲人工刺槐林健康状况分类

对刺槐林生长状况的准确分类制图,是刺槐林生长动态监测和枯梢退化原因分析的基础,这对指导防护林建设、更新以及研究区其它树种的植被重建具有重要的意义。该研究以黄河三角洲地区刺槐林为对象,采用2013年6月9日IKONOS影像为数据源,利用决策树分类器对归一化植被指数和土壤调节植被指数定义一组规则提取出刺槐林地分布范围,制作刺槐林地掩膜,创建灰度共生矩阵来区分健康树冠和林下禾草,结合实地样方调查信息,选取感兴趣区进行监督分类。刺槐林的三个健康度由原位的5个树冠条件指标决定。分类结果表明,刺槐林健康状况分类结果与实地样方数据具有较好的一致性,利用混合矩阵进行精度评价,总精度达到84.3159% ,Kappa系数为0.7652 。     

晋西黄土区不同林龄人工刺槐林下植被及土壤水分特征

以晋西黄土丘陵沟壑区10、15、20a人工刺槐林为研究对象,原生荒草地为对照,采用时空互代法,调查分析坡面刺槐人工林植被恢复过程中林下植被演替和0~400cm土层土壤水分分布情况.结果表明:随着人工刺槐林林龄的增加,林下灌草植被物种丰富度变大,植被结构发育变好;不同林龄刺槐林地与荒草地土壤平均含水量由大到小顺序为荒草地(16.61%)、20a刺槐林地(10.08%)、15a刺槐林地(9.54%)、10a刺槐林地(8.52%);随着刺槐林龄的增加,土壤水分随坡位下降而增大的趋势有所改变,成熟刺槐林对坡面土壤水分空间分配的调节作用明显;人工刺槐林土壤水分沿垂直剖面变化方式与原生荒草地差异明显,15a以上刺槐林对100cm以下土壤水分的影响已基本稳定;人工刺槐林的生长造成了严重的林地土壤水分亏空,随着林龄的增长0~200cm土层土壤水分条件有所改善,但深层土壤(200~400cm)没有明显的恢复迹象.研究结果为黄土区植被恢复和刺槐林的经营管理提供了科学依据.     

基于面向对象的长株潭地区遥感影像分类方法

结合Landsat TM遥感影像和环境减灾卫星HJ-1-A、B影像数据,基于面向对象的遥感影像分类技术实现长株潭地区土地利用/覆被的分类提取.综合利用隶属度函数和最邻近分类方法设置分类规则,逐步提取林地、湿地、耕地、人工表面的地物信息.以地形复杂多样的长株潭地区为研究区,收集整理具有代表性的样点用于分类和精度评价.结果表明,利用隶属度函数方法分类结果基本能满足生产者和用户的需要,但是林地、耕地内部二级类精度相对较低,错分比较严重,采用最邻近分类优化分类结果后,研究区总体分类精度达到86.05%,耕地和林地一级类分类精度分别提高到73.63%和87.1%.     

海州露天煤矿排土场植被恢复物种组成特征

为揭示海州露天煤矿排土场植被恢复物种组成特征,选取刺槐林地、榆树林地、灌木林地(紫穗槐)、混交林地(刺槐×榆树)、荒草地、耕地(玉米地)6种复垦植被为研究对象,对植被类型恢复特征进行研究.结果表明:在混交林中,榆树与刺槐混交比例为1∶0.67.四个林地的树高最大值为6.14m,最小值为2.31m,变异系数的最大值为9.52%,最小值3.34%,属于弱变异性;胸径最大值为6.53cm,最小值为4.02cm,变异系数最大值为15.29%,最小值为3.68%;树冠冠幅最大值为3.92m,最小值为1.56m,变异系数最大值为17.28%,最小值为1.03%.混交林内榆树的重要值为49.14%,刺槐的重要值为50.86%,刺槐林中榆树的重要值为27.73%,刺槐重要值为72.27%.除了耕地以外的其他样地的植被覆盖度均在95%以上,其中刺槐林植被覆盖度最高,为99%,榆树林地的植被覆盖度最低,为96%.     

黄土高原刺槐人工幼林碳密度动态变化

为研究黄土高原幼龄人工刺槐林地生态系统的有机碳动态变化规律,对刺槐林地在造林后4个阶段(造林2、4、6、9 a)生态系统各层次的有机碳储量进行了持续的监测与调查。结果表明:造林在2 a内对林地有机碳储量影响微小;造林2 a后,林地生态系统各层次有机碳密度均会随着林龄的增大而呈规律性变化,其中土壤层和乔木层为生态系统有机碳的主要来源,土壤层有机碳密度及其在林地有机碳密度中所占的比例随着林龄的增大而减小,乔木层有机碳密度呈相反变化趋势。由此,黄土高原人工刺槐林生态系统有机碳密度随着林龄的增大而增加,与荒地相比,林地有机碳密度分别增加了6.2%、5.21%、21.81%和38.20%,表明黄土高原人工刺槐林在造林后会逐步发挥其显著的碳汇能力。     

基于Landsat影像的面向对象土地利用分类——以下辽河平原为例

基于Landsat OLI影像运用支持向量机和随机森林分类方法进行下辽河平原地区面向对象土地利用分类,同时探讨DEM因素对分类精度的影响.结果表明:(1)研究区随机森林分类的总体精度和Kappa系数优于支持向量机分类的结果,同时参考DEM因素有助于提高分类精度,总体精度最高为91.80%.(2)研究区支持向量机分类方法下水田和建设用地的分类精度较高;而旱地、林地、水域和未利用地更适用于随机森林分类方法.DEM因素对于水田、旱地、水域及未利用地的分类精度有提升作用,而对林地的分类精度有一定的削减.(3) 2015年研究区土地利用以耕地为主,其次是建设用地和林地,水域、未利用地和草地的面积相对较少.中等分辨率遥感影像的面向对象土地利用分类的适用性较好,可为区域土地利用信息提取提供参考.     

和田河西岸荒漠林动态变化及其驱动力研究

该文基于遥感和地理信息系统等技术,以干旱区典型荒漠——绿洲——新疆和田河西岸为研究区,利用该地区2000年、2011年两个时段的多源卫星遥感数据(TM、HRV),采用主成分分析法和分层监督分类的方法,分别解译出2个时期的荒漠林数据.并对该区2000-2011年11年间的荒漠林数量、类型及其时空变化规律进行研究,得到该区2000-2011年荒漠林变化情况及其动态变化转移矩阵.结果显示:和田河西岸近11年来荒漠林数量呈增加趋势,其中疏林地变化强度最大;其他林地向有林地转移趋势、非林地向宜林地转移趋势最为明显,荒漠林整体向有利的趋势发展；变化的主导因素是政策因素和人为因素,其次是气候因素.     

基于多种植被指数的喀斯特流域赋水动态研究——以贵州省为例

植被指数是反映植被生长状况的指标,在一定程度上可用来反映植被覆盖率。利用植被指数监测喀斯特水资源不仅是为了了解喀斯特地区的流域赋水状态,也是研究地区脆弱性的重要内容。选取贵州省15个典型喀斯特流域,并应用软件ENVI计算出RVI、EVI、NDVI、DVI、RDVI、TVI、NDVItheta 7种植被指数。再利用SPSS软件中的主成分分析模块和回归分析模块,构建主成分Z与径流深之间的喀斯特流域赋水预测模型。通过样区检验,预测效果较好,精度较高。     

基MODIS影像对NDVI和EVI的分类研究

从MODIS影像中划出一块无云区域作为研究对象,求出该研究区的NDVI和EVI,运用K-均值分类法分别对2种植被指数进行非监督分类．通过对2种植被指数分类结果进行比较得出：2种植被指数的分类结果在总体上是一致的,但是在局部区域,NDVI对于水体的分辨能力优于EVI,而EVI对植被则有更强的分辨能力．2种植被指数分类结果精度评价总精度为70．00％,Kappa系数为0．585．     

基于HJ-1A1B卫星多光谱的油菜菌核病监测研究

为探索基于卫星平台的油菜菌核病遥感监测方法,于2011-2012年在新疆伊犁第四师77团油菜生长季节,对选定的健康、病害油菜地块叶面积指数（LAD、花面积指数（FAI）和角果面积指数（PAI）及光谱指数进行了研究。结果显示：健康油菜与病害油菜的归一化植被指数（NDVI）、比值植被指数（RVI）和差值植被指数（DVI）在发病前无明显著差异,但在发病之后有显著或极显著差异,基于显著差异性光谱指数采用的4种病害与非病害油菜分类方法中,以最大似然法分类结果与田间调查结果最接近,其kappa系数为0．72,达到高度的一致性。结论：利用NDVI、RVI和DVI可区分病害油菜与健康油菜,最大似然法是病害油菜与健康油菜分类的最佳方法,利用环境卫星多光谱数据进行油菜病害监测是可行的,精度符合生产要求。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Jane Eyre——A Feminist In The 19th Century

In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-