Studies on the reflectance spectral features of saline soil along the middle reaches of Tarim River: a case study in Xinjiang Autonomous Region, China

There has been growing interest in the use of reflectance spectroscopy as a rapid and inexpensive tool for soil characterization. In this study, 53 soil samples were collected from the oasis in the Weigan and Kuqa River delta along the middle reaches of Tarim River to investigate the level of soil chemical components in relation to soil spectral. An approach combining spectral technology and multi-variant statistical analysis was used to determine the reflectance spectral features of saline soil. The spectral data was first pretreated to remove noises and absorption bands from water, which eliminated influence from instrument errors and other external background factors. Several spectral absorption features were calculated for several saline soil samples to confirm that soil at the same salinity level had similar absorption spectral properties. Secondly, a correlation relationship between reflectance spectra and salinity factors was estimated by bivariate correlation method. Fourteen salinity factors including eight major ions and soil electrical conductivity (EC), soil salt content (SSC), pH, and total dissolved solid (TDS) in the saline soil were evaluated. Datasets of the salinity factors that correlated significantly with field data measurements of reflectance rate and the corresponding spectrum data were used to construct quantitative regression models. According to the multiple linear regression analysis, SSC, SO₄ ^2?, TDS, and EC had a correlation coefficient at 0.746, 0.908, 0.798, and 0.933 with the raw spectral data, respectively, which confirmed strong correlation between salinity factors and soil reflectance spectrum. Findings from this study will have significant impact on characterization of spectral features of saline soil in oasis in arid land.     

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保护地质环境 造福子孙后代

水资源存储及治理地面沉降问题的途径,德州市国土资源局通过山东省鲁北地质工程勘察院专家及有关技术人员,在对地面沉降区大量勘查及对相关数据资料分析研究,反复论证基础上,实施了“山东省德州市城区深层地下水人工回灌试验”项目。他们根据设计要求,进一步详细收集城区地质水文资料,布置了20个动态监测点,观测分析深层地下水的变化规律。在掌握深层地下水降落漏斗范围的中心水位基础上,选定区域进行了地下水回灌试验,回灌时间360h,回灌量7500m3;回灌试验期间最大回灌量达31.0m3/h,水位上升16.95m,最小回灌量6.6m3/h,水位上升3.28m。表明回…     

COMMUNITY-BASED ECOTOURISM IN NATURE RESERVE OF CHINA

This paper introduces a new concept of community-based ecotourism (CBET) that originated in foreign countries. Then it analyzes the significance of CBET development in nature reserve (NR). The authors think that community participation is the evitable choice of nature reserve‘s conservation and development. CBET, as the self-improved model ofecotourism, can promote tourism community sustainable development. Based on the stakeholder analysis of CBET in NRs, this paper addresses the reality, especially the problem of CBET development in NRs of China. In order to develop CBET in NRs of China, this paper takes some suggestions to promote the community participation: 1)gradual political empowerment, 2) deep level economic incentive, 3) widespread educational support, 4) impartial distribution of community benefits, and 5) stakeholders cooperation.     

鄂尔多斯盆地北部中元古界潜山圈闭特征与成藏模式

鄂尔多斯盆地深层发育长城纪裂陷槽,但相关的圈闭类型和成藏条件不清。近期,在盆地北部杭锦旗地区发现了长城系砂岩潜山气藏,揭示该领域具有较好的勘探前景。通过最新的三维地震和钻井资料综合分析,结合区域构造演化阶段和典型气藏解剖,本次研究针对中元古界潜山圈闭的分布、类型及天然气成藏模式展开。结果表明：(1)研究区长城纪发育三个NW向裂陷槽,其中的独贵、蒋家梁裂陷槽受基底断裂反转活动影响,隆升剥蚀,形成低幅度的潜山隆起带;(2)残丘、隐丘及断丘型圈闭沿潜山隆起带呈带状分布,其中断丘型圈闭的闭合幅度最高;(3)潜山圈闭的成藏模式可分“上生下储”、“源储侧接”及“源外运移”等三种类型;(4)天然气藏分布受四个因素控制,其中烃源岩分布制约潜山气藏的分布范围;圈闭类型控制气藏规模与富集程度;断-缝发育程度控制储层物性及含气性;而侧向输导控制源外圈闭的成藏效率。因此,邻近煤系烃源岩的断丘型、残丘型圈闭将是研究区中元古界潜山勘探的首要目标。     

苏拉威西岛北部左旋走滑与俯冲后撤的动力学分析

苏拉威西岛北部属于马鲁古海板块,其主体是北苏拉威西海沟俯冲带与帕卢-科洛左旋走滑断裂所围限的岛北支和岛东支。大约5 Ma前,苏拉群岛沿Sorong断层与苏拉威西岛东支碰撞,导致北苏拉威西海沟俯冲后撤,引起了岛北支顺时针旋转约20°～25°,同时,西侧的帕卢-科洛断层发生了约4 cm/a的左旋走滑。本文利用综合地球物理方法,计算了该区三维温度、速度、黏性特征,认为：苏拉威西岛北部在左旋走滑、俯冲后撤过程中,地壳以脆性变形为主,但由于北苏拉威西海沟俯冲带在地壳内形成南向倾斜的软弱层,Moho面和地形“镜像”区域内形成脆、韧变形共存的组合。地幔变形为韧性变形,深度约100 km的上地幔低速流变层是地幔韧性变形的主控层位。在周边板块边界不断移动的动力学背景中,苏拉威西岛北部在地壳尺度以收缩-伸展变形为主,在岩石圈尺度以旋转变形为主。     

传感器节点环境能量的收集方法

探讨了太阳能、振动能和气流能等3种潜在的环境能量及其利用方法。这些方法可有效解决传感器网络节点需要足够持续的能量而传统的电池供能方式不能满足的实际问题。     

病态平差模型直接解算方法的研究

基于矩阵的SVD理论，通过修改设计阵的奇异值，提出了若干种直接解算病态(满秩或秩亏)观测方程的方法，以改善设计阵的病态性，提高参数估值的稳定性和准确性。理论分析和数值计算的结果验证了这些解算方法的优良性。     

基于CPLD实现网上教学加密

针对网上教学系统关键技术,提出了一种采用CPLD来实现三重DES加密算法的设计方法.最后用一片Altera的MAX7128S实现了该算法.     

羌塘地体内部双湖—冈玛错—龙木错构造带地质与地球物理特征

本文概要总结了羌塘地体内部的双湖—冈玛错—龙木错构造带地质与地球物理特征。从地表出露的蓝闪片岩、混杂堆积和生物古地理特征的差异,以及重力异常带分布、Pn波异常特征及地震层析成像等可以看出,双湖—冈玛错—龙木错构造带很可能是冈瓦那大陆和欧亚大陆之间的缝合带。