Geospatial and statistical interpretation of lineaments: salinity intrusion in the Kribi-Campo coastland of Cameroon
Geospatial and statistical interpretation of lineaments: salinity intrusion in the Kribi-Campo coastland of Cameroon
复制标题
DOI：
10.1016/j.asr.2020.05.002
复制
发表时间：
2020-08-15
影响因子：
2.6
通讯作者：
Richter, Goetz
中科院分区：
文献类型：
--
作者：
Aretouyap, Zakari;Billa, Lawal;Richter, Goetz
这项研究探测、绘制和分析了喀麦隆Kribi-Campo沿海地区Landsat-8卫星图像的线性构造。克里比是一个发展迅速的沿海城市，人口年轻，主要产业是农业，目前由于国内流离失所者的涌入而面临巨大压力，这些人是喀麦隆西部当前社会政治危机的受害者。随着对粮食和水资源的需求不断增长，据报告，盐碱地和地下水正在影响该地区的农业生产力和家庭供水。本文通过研究该地区的线性构造网络，了解其空间分布、范围及其对内陆咸水入侵的潜在影响。使用主成分分析和过滤技术处理了数据集，包括大地卫星8号图像、地质数据和数字高程模型。利用假彩色合成图像纹理变化增强线状特征，描述断裂、断层和水文特征。从这些图像中自动和手动提取了390个有效的线性构造，并使用统计分析基于长度、密度和方向进行分析。但在此之前处理，无效的线性构造，可能对应于阶地，线性山谷，悬崖，或色调对比以及人类活动已被删除。有效线性体长度范围为95 - 4910 m，平均长度为1171 m。虽然线性构造不是各向同性的，但它们与海岸的垂直方向表明盐水可能侵入区域地下水资源和农田。本文提出了一种地理空间和统计分析相结合的技术，在解释的线性效应，有可能告知沿海地区的盐度入侵。通过对研究区50个地下水样品的电导率测试，验证了线性构造对海水入侵的影响。(C)2020年空间研委会。由爱思唯尔有限公司出版。保留所有权利。
This study detected, mapped and analysed lineaments from Landsat-8 satellite images of the coastal area of Kribi-Campo, Cameroon. Kribi, a fast-growing coastal city with a youthful population whose main industry is agriculture, is currently under great pressure due to the influx of internally displaced persons, victims of the current socio-political crisis in the western part of Cameroon. With the growing demand for food and water resources, it has been reported that saline soils and groundwater are affecting the agricultural productivity and domestic water supply of the area. This paper investigates the lineaments network in this area to understand its spatial distribution, its extent and the potential effect on inland intrusion of saline water. The datasets, including Landsat-8 imagery, geological data and a digital elevation model were processed using principal component analysis and filtering techniques. Linear features were enhanced based on textural changes of false colour composite images to describe fractures, faults and hydrology features. 390 effective lineaments were extracted automatically and manually from those images and analysed based on length, density and orientation using statistical analysis. But before this processing, non-effective lineaments that may correspond to terraces, linear valleys, cliffs, or tonal contrast as well as to human activities have been deleted. The effective lineaments range in length from 95 to 4910 m with an average of 1171 m. Although the lineaments are not isotropic, their perpendicular orientations to the coast suggest potential intrusion of saline water into regional groundwater resources and farmlands. The paper presents a combined technique of geospatial and statistical analysis in the interpretation of lineament effects which have the potential to inform on salinity intrusion in coastlands. The electrical conductivity of 50 groundwater samples collected in the study area are used to validate the impact of lineaments on seawater intrusion. (C) 2020 COSPAR. Published by Elsevier Ltd. All rights reserved.