Removing the Effects of Water From Visible-Near Infrared Spectra in Soil Profiles for the Estimation of Organic Carbon [基于野外可见近红外光谱和水分影响校正算法的土壤剖面有机碳预测]
作者：
李硕;李春莲;陈颂超;徐冬云;史舟
期刊：
光谱学与光谱分析 ,2021年41(4):1234-1239 ISSN：1000-0593
通讯作者：
Shi, Zhou(shizhou@zju.edu.cn)
作者机构：
[李硕; 李春莲] Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province, Central China Normal University, Wuhan;430079, China;[徐冬云; 史舟] Institute of Remote Sensing and Information Technology, Zhejiang University, Hangzhou;310058, China;[陈颂超] INRAE, Unité InfoSol, Orléans
通讯机构：
[Shi, Z.] I;Institute of Remote Sensing and Information Technology, China
关键词：
土壤有机碳;外部参数正交化;分段直接标准化;随机森林;青藏高原
摘要：
土壤是陆地碳循环的中枢,充分发挥土壤固碳潜力有助于减缓全球气候变化。土壤有机碳（SOC）的高度分异性同时体现在空间和垂直分布上,但是许多前期研究往往只考虑了空间分异,而忽略了垂直分异。尤其在青藏高原这种高寒山区,土壤样品采集难度较大且费用昂贵。可见近红外（Vis-NIR）光谱作为传统土壤实验室化学分析的辅助手段,能够较为快速和精准地估测SOC含量。但是土壤水分等环境因素会掩盖或改变SOC的Vis-NIR光谱吸收特征进而削弱模型预测精度。外部参数正交化（EPO）和分段直接标准化（PDS）算法可以有效校正水分对光谱的影响,但其在野外新鲜土柱上的表现还不得而知。本研究旨在探索不同水分影响校正算法对野外剖面土壤光谱的校正能力,对采自中国青藏高原海拔2 900～4 500m色季拉山的共26个1m深土柱。沿深度以5cm×5cm为测量单元,从各单元中心采集共计386个野外原状湿样Vis-NIR光谱,并在实验室内测得相应386个研磨干样的Vis-NIR光谱以及SOC含量。经EPO和PDS算法校正土壤水分对光谱的影响后,通过随机森林建立土壤光谱和SOC含量的定量预测模型,并使用靴襻法评估不同校正处理下预测模型的不确定。土柱整体及垂直分布的精度结果表明,经PDS法转换的农田和草地土柱湿样光谱均表现出良好的水分校正效果,而EPO法仅对农田土柱有效。水分影响校正算法在不同土壤深度上也存在显著差异,EPO和PDS对农田和草地表层样本的水分校正均效果明显。两种校正方法的效果显示出地类和土层深度的依赖性。本研究为利用Vis-NIR光谱技术在高寒山区野外快速准确估算土壤碳含量的垂直分异提供了必要参考。
语种：
中文
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Simulating spatiotemporal land use change in middle and high latitude regions using multiscale fusion and cellular automata: The case of Northeast China
作者：
Wu, Xia;Lin, An-Qi;Li, Yan;Wu, Hao;Cen, Lu-Yu;...
期刊：
Ecological Indicators ,2021年133:108449 ISSN：1470-160X
通讯作者：
Wu, Hao(haowu@mail.ccnu.edu.cn)
作者机构：
[Wu, Xia; Lin, An-Qi; Li, Yan; Wu, Hao; Cen, Lu-Yu; Liu, He; Song, Dan-Xia] Hubei Provincial Key Laboratory for Geographical Process Analysis and Simulation, Central China Normal University, Wuhan;430079, China;College of Urban and Environmental Sciences, Central China Normal University, Wuhan;[Wu, Xia; Lin, An-Qi; Li, Yan; Wu, Hao; Cen, Lu-Yu; Liu, He; Song, Dan-Xia] 430079, China<&wdkj&>College of Urban and Environmental Sciences, Central China Normal University, Wuhan;[Wu, Xia; Lin, An-Qi; Li, Yan; Wu, Hao; Cen, Lu-Yu; Liu, He; Song, Dan-Xia] 430079, China
通讯机构：
[Hao Wu] H;Hubei Provincial Key Laboratory for Geographical Process Analysis and Simulation, Central China Normal University, Wuhan 430079, China<&wdkj&>College of Urban and Environmental Sciences, Central China Normal University, Wuhan 430079, China
关键词：
CA-Markov model;Data fusion;Land use change;Land use simulation;Majority Voting
摘要：
Global warming-induced land use change in middle and high latitude regions remains an important and challenging topic for sustainable development. Although a large amount of remote sensing imageries is available for extracting land use information, there are unavoidable inconsistencies among land use products from different platforms. This study proposes a framework which integrates multiscale fusion method and cellular automata to simulate spatiotemporal land use change in middle and high latitude regions. Five types of remote sensing-based land use products were used to extract land use information of Northeast China in 2001, 2009, and 2017. The results demonstrate that the fused land use product from the integration of remote sensing-multiscale fusion and cellular automata has a higher accuracy. The simulated land use map for 2017 using CA-Markov model was validated by the actual land use classification of 2017, and the stochastic Kappa (Kno), location related Kappa (Klocation) and traditional Kappa (Kstandard) were 0.90, 0.94 and 0.86, respectively. The results of land use change from 2001 to 2017 show the biggest increase (5.9%) in farmland, mainly from grassland and forest. The predicted results indicate that this trend will persist until 2025 with a continuous augmentation of farmland in Northeast China. The areas of grassland will decrease by 4.3% from 2017 to 2025, with a major conversion to farmland and forest. The increasing farmland is a potential threat to ecology environment in the region as it will heavily sacrifice grassland and forest. These findings provide useful information on understanding spatiotemporal land use change in middle and high latitude regions and allow us maintaining food security for sustainable development. © 2021
语种：
英文
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Forest land quality evaluation and the protection zoning of subtropical humid evergreen broadleaf forest region based on the PSOTOPSIS model and the local indicator of spatial association: A case study of Hefeng County, Hubei Province, China
作者：
Wang, Li;Zhou, Yong;Li, Qing;Zuo, Qian;Gao, Haoran;...
期刊：
Forests ,2021年12(3) ISSN：1999-4907
通讯作者：
Zhou, Yong(yzhou@mail.ccnu.edu.cn)
作者机构：
[Gao, Haoran; Wang, Li; Li, Qing; Zuo, Qian; Zhou, Yong; Tian, Yang; Liu, Jingyi] Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Peoples R China.;[Gao, Haoran; Wang, Li; Li, Qing; Zuo, Qian; Zhou, Yong; Tian, Yang; Liu, Jingyi] Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan 430079, Peoples R China.;[Gao, Haoran; Wang, Li; Li, Qing; Zuo, Qian; Zhou, Yong; Tian, Yang; Liu, Jingyi] Cent China Normal Univ, Land Sci Res Ctr, Wuhan 430079, Peoples R China.
通讯机构：
[Zhou, Y.] T;[Zhou, Y.] K;[Zhou, Y.] L;Land Science Research Center, China;The College of Urban & Environmental Sciences, China
关键词：
Forest land quality;Hefeng County;LISA;Protection zoning;PSO-TOPSIS model
摘要：
Forest land is the carrier for growing forests. It is of great significance to evaluate the forest land quality scientifically and delineate forestland protection zones reasonably for realizing better forest land management, promoting ecological civilization construction, and coping with global climate change. In this study, taking Hefeng County, Hubei Province, a subtropical humid evergreen broad-leaved forest region in China, as the study area, 14 indicators were selected from four dimensions—climatic conditions, terrain, soil conditions, and socioeconomics—to construct a forest land quality evaluation index system. Based on the Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) model, we introduced the Particle Swarm Optimization (PSO) algorithm to design the evaluation model to evaluate the forest land quality and analyze the distribution of forest land quality in Hefeng. Further, we used the Local Indicator of Spatial Association (LISA) to explore the spatial distribution of forest land quality and delineate the forest land protection zones. The results showed the following: (1) the overall quality of forest land was high, with some variability between regions. The range of Forest Land Quality Index (FLQI) in Hefeng was 0.4091–0.8601, with a mean value of 0.6337. The forest land quality grades were mainly first and second grade, with the higher-grade forest land mainly distributed in the central and southeastern low mountain regions of Zouma, Wuli, and Yanzi. The lower-grade forest land was mainly distributed in the northwestern middle and high mountain regions of Zhongying, Taiping, and Rongmei. (2) The global spatial autocorrelation index of forest land quality in Hefeng County was 0.7562, indicating that the forest land quality in the county had a strong spatial similarity. The spatial distribution of similarity types high-high (HH) and low-low (LL) was more clustered, while the spatial distribution of dissimilarity types high-low (HL) and low-high (LH) was generally dispersed. (3) Based on the LISA of forest land quality, forest land protection zones were divided into three types: key protection zones (KPZs), active protection zones (APZs), and general protection zones (GPZs). The forest land protection zoning basically coincided with the forest land quality. Combining the characteristics of self-correlated types in different forestland protection zones, corresponding management and protection measures were proposed. This showed that the PSO-TOPSIS model can be effectively used for forest land quality evaluation. At the same time, the spatial attributes of forest land were incorporated into the development of forest land protection zoning scheme, which expands the method of forest land protection zoning, and can provide a scientific basis and methodological reference for the reasonable formulation of forest land use planning in Hefeng County, while also serving as a reference for similar regions and countries. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.
语种：
英文
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Evaluating validation strategies on the performance of soil property prediction from regional to continental spectral data
作者：
Chen, Songchao;Xu, Hanyi;Xu, Dongyun;Ji, Wenjun;Li, Shuo;...
期刊：
Geoderma ,2021年400:115159 ISSN：0016-7061
通讯作者：
Shi, Zhou(shizhou@zju.edu.cn)
作者机构：
[Wang, Nan; Xu, Hanyi; Shi, Zhou; Chen, Songchao; Zhou, Yin; Xu, Dongyun] Zhejiang Univ, Coll Environm & Resource Sci, Inst Appl Remote Sensing & Informat Technol, Hangzhou 310058, Peoples R China.;[Chen, Songchao; Arrouays, Dominique] INRAE, Unite InfoSol, F-45075 Orleans, France.;[Ji, Wenjun] China Agr Univ, Coll Land Sci & Technol, Beijing 100085, Peoples R China.;[Li, Shuo] Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat, Wuhan 430079, Peoples R China.;[Yang, Meihua] Yuzhang Normal Univ, Dept Environm Engn, Nanchang 330103, Jiangxi, Peoples R China.
通讯机构：
[Zhou Shi] I;Institute of Applied Remote Sensing and Information Technology, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China<&wdkj&>Key Laboratory of Spectroscopy Sensing, Ministry of Agriculture and Rural Affairs, Hangzhou 310058, China
关键词：
Calibration sampling;Clay;Model robustness;Proximal soil sensing;Soil organic carbon;Vis–NIR spectra
摘要：
Visible-near infrared (vis–NIR) spectroscopy has been widely used to characterize soil information from field to global scales. Before applying a calibrated spectral predictive model to acquire soil information, either independent validation or k-fold cross validation is used to evaluate model performance. However, there is no consensus on which validation strategy is more suitable and robust when evaluating model performance for the studies in different scales. The objective of this study is to evaluate and compare the model performance of two validation strategies coupling different calibration sizes (a ratio of calibration to validation of 2:1, 4:1 and 9:1) and calibration sampling strategies (random sampling (RS), rank, Kennard-Stone (KS), rank-Kennard-Stone (RKS) and conditioned Latin hypercube sampling (cLHS)) across scales. A total of 17,272 vis–NIR spectra of mineral soils from LUCAS data (continental scale) and their soil organic carbon (SOC) and clay contents were used in this study, and the dataset was further split into national (2761 samples in France) and five regional datasets (110 to 248 samples from five French administrative regions). To eliminate the effect of changing validation set on the model performance, a consistent test set (20% of total samples at each scale) was split to evaluate all the combinations involved in two validation strategies. The Lin's concordance correlation coefficient (CCC) of the cubist model were stable for both SOC and clay for different calibration sizes, calibration sampling and validation strategies for a large calibration size (>1400) at the national and continental scales. A larger calibration size can potentially improve model performance for a small dataset (<300) at the regional scale, and a wider calibration range would result in better model performance. No silver bullet was found among the different calibration sampling strategies at the regional scale. For five French regions (small data set), we found a high variation (95th percentile minus the 5th percentile) in the CCC among the models built from 50 repeated RS (0.10–0.44 for SOC, 0.16–0.52 for clay) and cLHS (0.08–0.40 for SOC, 0.12–0.36 for clay). This finding indicates that a one-time RS or cLHS for selecting the calibration set has high uncertainty in model evaluation for a small dataset and therefore should be used with caution. Therefore, we suggest the following: (1) for a large data set (thousands), either one-time random sampling for independent validation or k-fold cross validation would be appropriate; (2) for a small data set (dozens to hundreds), k-fold cross validation and/or repeated random sampling for independent validation would be more robust for spectral predictive model evaluation. © 2021 Elsevier B.V.
语种：
英文
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中国3000年疫灾流行的时空特征及其影响因素
作者：
龚胜生;李孜沫;谢海超;王晓伟;张涛;...
期刊：
地理学报 ,2021年76(8):1976-1996 ISSN：0375-5444
作者机构：
[龚胜生; 张涛; 石国宁] College of Urban and Environmental Sciences Research Institute of Sustainable Development, Central China Normal University, Wuhan;430079, China;[李孜沫] School of Tourism and Economic Management, Nanchang Normal University, Nanchang;330032, China;[谢海超; 陈发虎] Group of Alpine Paleoecology and Human Adaptation, State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing
关键词：
瘟疫灾害;时空特征;影响因素;疫灾周期;历史时期;中国
摘要：
疫灾是人类灾害链网中的顶级灾害。利用历史疫灾史料,建立疫灾时间序列,使用历史断面分析、因子相关分析、时间序列分析等方法,对中国过去2720年疫灾流行的时空特征及其影响因素进行研究。结果表明:（1）中国疫灾流行的频度和强度有长期上升趋势,温暖期形成疫灾低谷,寒冷期形成疫灾高峰。（2）中国疫灾流行总体以夏、秋季为主,但有阶段性差异,15世纪50年代以后,由于疫病种类增多,疫灾频度提高,疫灾的季节性差异逐渐不显著。（3）中国疫灾波动周期主要有620～610 a、320～310 a、230～220 a、170 a、90 a等,它们大都是12 a或11.2 a的倍数,反映了"十二地支"周期的存在和太阳黑子活动对疫灾周期的重大影响。（4）过去近3000年里,中国累积的疫灾广泛度为93.51%,疫灾厚度达16.86层,东南半壁的疫灾比西北半壁的频繁得多、严重得多。（5）中国疫灾区域拓展与土地开发同步,疫灾重心变迁受经济重心的牵引,南宋以前由北向南迁移,南宋以后由东向西迁移;外来疫病输入对疫灾分布格局产生重大影响。（6）疫灾流行既是自然生态现象,也是社会文化现象,疫灾时空分布变迁反映人地关系变迁,人口稠密区、交通沿线区、都城周边区、自然疫源区、灾害频发区都是疫灾多发区。（7）地理环境分异奠定疫灾空间分异,高温、高湿、低海拔地区疫灾易于流行;自然灾害对疫灾具有诱发作用,灾害频繁区也是疫灾频发区,灾害频繁期也是疫灾频繁期;气候变迁影响疫灾波动,寒冷期疫灾多发,温暖期疫灾少发;人口增加带来的土地开发和人地关系紧张,加剧疫灾的流行;疫灾与战争如影随形,战乱频繁期也是疫灾频繁期。
语种：
中文
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Soil moisture seasonality alters vegetation response to drought in the Mongolian Plateau
作者：
Lu, Zihan;Peng, Shushi* ;Slette, Ingrid;Cheng, Guoquan;Li, Xiran;...
期刊：
ENVIRONMENTAL RESEARCH LETTERS ,2021年16(1):014050 ISSN：1748-9326
通讯作者：
Peng, Shushi
作者机构：
[Lu, Zihan; Peng, Shushi; Cheng, Guoquan] Peking Univ, Coll Urban & Environm Sci, Sino French Inst Earth Syst Sci, Lab Earth Surface Proc, Beijing, Peoples R China.;[Slette, Ingrid; Chen, Anping] Colorado State Univ, Dept Biol, Ft Collins, CO 80523 USA.;[Slette, Ingrid; Chen, Anping] Colorado State Univ, Grad Degree Program Ecol, Ft Collins, CO 80523 USA.;[Li, Xiran] Cent China Normal Univ, Coll Urban & Environm Sci, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Peng, Shushi] P;Peking Univ, Coll Urban & Environm Sci, Sino French Inst Earth Syst Sci, Lab Earth Surface Proc, Beijing, Peoples R China.
关键词：
Climate change;Drought;Grasslands;Livestock;Mongolia Plateau;Vegetation productivity
摘要：
The Mongolian Plateau (MP) experienced the most severe decadal drought of the past two millennia from 2000 to 2009 and several shorter-term droughts in the 2010s. Using satellite-based near-infrared reflectance of vegetation (NIRV), we examined changes in vegetation productivity of the MP from 2000 to 2018. During this time, soil moisture in March (SMMar) mainly determined spring NIRV, and early-summer (June and July) precipitation mainly determined summer NIRV. Our study revealed three distinct periods: the severely dry period of 2000–2009, recovery in 2010–2012, and a relatively stable period with occasional short-term droughts after 2012. While vegetation productivity experienced a significant decrease during the severe decadal drought, summer and spring productivity quickly recovered after 2010, following an increase in growing season (GS) rainfall and winter snowfall. Greater SMMar, which resulted from previous GS precipitation, contributed to smaller declines in vegetation productivity during the short-term droughts in 2014, 2015 and 2017. The decline in vegetation productivity during the severe decadal drought damaged livestock operations in Mongolia, but had a limited effect on operations in Inner Mongolia of China, where human intervention is stronger. Given evidence that drought impacts are increasing worldwide, it is important to understand the factors determining ecosystem drought responses. Many drought studies have focused on GS precipitation, but our results show that pre-GS SM can play an important role in determining drought impacts. Our results also demonstrate that strong interventions will be needed in order to sustain livestock operations during intensifying drought. © 2021 The Author(s). Published by IOP Publishing Ltd
语种：
英文
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Object-Oriented and Deep-Learning-Based High-Resolution Mapping from Large Remote Sensing Imagery [Cartographie haute résolution basée sur les approches orientée-objet et l’apprentissage profond à partir de grandes images de télédétection]
作者：
Wu, Yijin;Zhang, Pengfei;Wu, Jing;Li, Chang*
期刊：
Canadian Journal of Remote Sensing ,2021年47(3):396-412 ISSN：0703-8992
通讯作者：
Li, Chang
作者机构：
[Wu, Jing; Zhang, Pengfei; Wu, Yijin; Li, Chang] Cent China Normal Univ, Coll Urban & Environm Sci, Key Lab Geog Proc Anal & Simulat, Wuhan, Hubei, Peoples R China.
通讯机构：
[Chang Li] K;Key Laboratory for Geographical Process Analysis and Simulation, College of Urban and Environmental Science, Central China Normal University, Hubei Province, China
摘要：
Land use and land cover (LULC) mapping is a basic research topic in geography. In deep-learning (DL)-based LULC mapping, there are primarily the following issues: training and testing samples for DL are typically annotated by indoor visual interpretation without field surveys; remotely sensed scene classification based on DL typically lacks fine geometric boundaries for ground objects; historical big data (HBD) (e.g., vector data) are underutilized in DL; studies of large-scale remote sensing mapping (LSRSM) using DL are rare. To solve above issues, this paper proposes an object-oriented (i.e., polygon-based) and DL-based (OODLB) image classification method assisted by HBD for LSRSM to serve for monitoring the soil erosion and water loss (SEWL) in the Yangtze River Basin that includes the following steps: (1) using HBD and OpenStreetMap data, ground objects are vectorized; (2) a remote sensing interpretation key database is established by field surveys and data augmentation; (3) object-oriented (i.e., polygon-based) and Inception-ResNet-V2-based LULC mapping is performed; (4) DL-based classification results are updated by man-machine mutual verification. The experimental results of one county of the Yangtze River Basin show state-of-the-art performance with an overall accuracy of 90.20% in comparison of 75.60% for eCognition. It provides an excellent framework for OODLB large-scene mapping. ©, Copyright © CASI.
语种：
英文
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基于隐性—韧性—显性的武汉城市资源环境承载力空间特征
作者：
吴浩;江志猛;林安琪;朱文超;王伟
期刊：
地理学报 ,2021年76(10):2439-2457 ISSN：0375-5444
作者机构：
[Wu, Hao; 江志猛; 林安琪; 吴浩; 王伟] College of Urban and Environmental Sciences, Central China Normal University, Wuhan;430079, China;Hubei Province Key Laboratory for Geographical Process Analysis and Simulation, Wuhan;[Wu, Hao; 江志猛; 林安琪; 吴浩; 王伟] 430079, China<&wdkj&>Hubei Province Key Laboratory for Geographical Process Analysis and Simulation, Wuhan;[Wu, Hao; 江志猛; 林安琪; 吴浩; 王伟] 430079, China
关键词：
城市资源环境承载力;空间特征;城市韧性;空间自相关;分形几何;武汉市
摘要：
资源环境承载力是衡量城市国土空间发展状况的晴雨表,深入揭示资源环境承载力系统要素的相互作用机理对城市国土空间格局优化具有重大意义。本文在双评价指南的基础上引入夜光/大气遥感、兴趣点、交通态势、社交媒体等多源时空数据,建立了基于隐性—韧性—显性的城市资源环境承载力空间特征分析理论框架,提出了空间自相关和分形几何相结合的承载力空间特征挖掘方法。以武汉市为例开展研究,结果表明:①武汉市资源环境承载力呈显著空间异质性,隐性承载力指数高值区分布于城市外围生态环境优越的区域,韧性承载力指数高值区集中于综合风险应对能力较强的中心城区,显性承载力指数高值区位于各项基础功能均较为健全的城市次中心一带;②武汉市资源环境承载力存在正向空间聚集性,并呈显著半径向心分形特征,隐性承载力指数高值区呈放射状向四周扩散,韧性承载力指数高值区呈向心状聚集在城市核心圈层,显性承载力指数高值区分布于则介于二者之间。本文构建的城市资源环境承载力空间特征分析与挖掘方法体系,通过引入多源时空数据弥补了传统数据现势性的不足,完善了城市资源环境承载力研究的理论和技术范式,可为新时期城市资源环境承载力研究提供一种新思路。
语种：
中文
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Evaluation of urban water ecological civilization: A case study of three urban agglomerations in the Yangtze River Economic Belt, China
作者：
Tian, Pei* ;Wu, Huaqing;Yang, Tiantian;Jiang, Faliang;Zhang, Wenjie;...
期刊：
Ecological Indicators ,2021年123:107351 ISSN：1470-160X
通讯作者：
Tian, Pei
作者机构：
[Liu, Muxing; Jiang, Faliang; Tian, Pei; Wu, Huaqing; Yue, Qimeng; Zhang, Wenjie] Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan 430079, Peoples R China.;[Yang, Tiantian] Univ Oklahoma, Sch Civil Engn & Environm Sci, Norman, OK 73019 USA.;[Zhu, Zhanliang] Univ Edinburgh, Sch Geosci, Edinburgh EH8 9XP, Midlothian, Scotland.;[Xu, Xinyi] Beijing Normal Univ, Coll Water Sci, Beijing 100875, Peoples R China.;[Tian, Pei] Cent China Normal Univ, 152 Luoyu Rd, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Tian, Pei] C;Cent China Normal Univ, 152 Luoyu Rd, Wuhan 430079, Hubei, Peoples R China.
关键词：
Urban water ecological civilization;Multicriteria analysis;Entropy method;Spatial difference;Urban agglomeration;The Yangtze River Economic Belt
摘要：
Urbanization and economic development pose a challenge to the water ecological environment of cities. “Ecological Civilization” is a term that demonstrates the strategy to achieve the win-win goal of economic development and eco-environment protection. “Water Ecological Civilization” is a vital part of “Ecological Civilization”. This paper introduced a composite index to characterize the Urban Water Ecological Civilization (UWEC) and established an evaluation index system for UWEC based on a multicriteria analytical framework. The evaluation system contains 20 indicators selected from six criterion layers: water resources utilization (A, evaluating the efficiency of industrial, agricultural, domestic and public water use), water security assurance (B, evaluating the flood control, drainage and drinking water safety), water environmental protection (C, evaluating the water environment quality and water pollution prevention), water ecological restoration (D, evaluating the health of regional water ecosystem), water culture system (E, evaluating the inheritance of water culture and the popularization of UWEC awareness) and water management institution (F, evaluating the implementation of management systems). In our research, three major urban agglomerations (UAs) in Yangtze River Economic Belt (YREB) were chosen to be the study area. The results presented that the UWEC level of UAs gradually increased along the Yangtze River from west to east, showing obvious spatial differences. The main criteria restricting the UWEC level of UAs in the Yangtze River Delta were D and E, while E and F were the main restricting criteria for the UWEC level of UAs in the Middle Reaches of the Yangtze River and Cheng-Yu District. The indicator of “drainage compliance rate” got the lowest score among all indicators for three UAs. In addition, targeted measures for improving the UWEC level of UAs in YREB were proposed. Our study is supposed to provide a scientific reference to the improvement of UWEC level for UAs in YREB and trigger further research in the field of water ecological civilization. © 2021 The Author(s)
语种：
英文
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Clarifying the response of soil organic carbon storage to increasing temperature through minimizing the precipitation effect
作者：
Tan, Qiqi;Han, Wenxuan;Li, Xiran;Wang, Guoan*
期刊：
Geoderma ,2020年374:114398 ISSN：0016-7061
通讯作者：
Wang, Guoan
作者机构：
[Tan, Qiqi; Wang, Guoan] China Agr Univ, Coll Resources & Environm Sci, Dept Environm Sci & Engn, Beijing Key Lab Farmland Soil Pollut Prevent & Re, Beijing 100193, Peoples R China.;[Tan, Qiqi] Chinese Acad Agr Sci, Inst Agr Resources & Reg Planning, Natl Hulunber Grassland Ecosyst Observat & Res St, Beijing 100081, Peoples R China.;[Tan, Qiqi; Li, Xiran] Colorado State Univ, Dept Biol, Ft Collins, CO 80523 USA.;[Tan, Qiqi; Li, Xiran] Colorado State Univ, Grad Degree Program Ecol, Ft Collins, CO 80523 USA.;[Han, Wenxuan] China Agr Univ, Coll Resources & Environm Sci, Dept Ecol & Ecol Engn, Beijing 100193, Peoples R China.
通讯机构：
[Wang, Guoan] C;China Agr Univ, Coll Resources & Environm Sci, Dept Environm Sci & Engn, Beijing Key Lab Farmland Soil Pollut Prevent & Re, Beijing 100193, Peoples R China.
关键词：
Carbon stock;Climate change;Global carbon cycle;Global warming;Temperature gradient
摘要：
Considerable attention has been paid to the variation of soil organic carbon (SOC) storage along a temperature gradient. However, the results varied across studies. This inconsistence could be associated with the interference of the precipitation effect. To minimize the interference, this study collected soil samples over broad geographical scale along the 400 mm isohyet in China. Our results showed that SOC storage responded negatively to increasing temperature with a response coefficient of 0.24. Temperature explained more than half of the variability in SOC stock, which was much greater than the combined effects of water availability, soil properties, vegetation type and soil type. The negative relationship between SOC stock and temperature was not affected by vegetation type and soil type, suggesting that this correlation might be a general pattern. © 2020 Elsevier B.V.
语种：
英文
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地理信息数据分级评价的相对指数熵模型
作者：
肖佳;田沁;何宗宜
期刊：
测绘学报 ,2020年49(11):1497-1505 ISSN：1001-1595
作者机构：
[肖佳] School of Urban and Environmental Sciences, Central China Normal University, Wuhan;430079, China;Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province, Central China Normal University, Wuhan;[田沁] Shenzhen Research Center of Digital City Engineering, Shenzhen;518034, China
关键词：
相对指数熵;地理信息数据分级;分级评价模型;人口普查数据
摘要：
提出了一种基于相对指数熵的地理信息数据分级评价模型,构建级内相对指数熵与级间指数熵指标,分别量化分级数据级别内集聚水平和级别间的离散水平,并利用这两个指标构建了地理信息数据分级的相对指数熵评价指标。在Python中实现地理信息数据分级以及分级的相对指数熵计算。试验中,应用5种常用的分级方法对5种典型分布的6个数据集以及1个人口普查数据集进行分级,并分别计算分级结果的相对指数熵指标。试验结果表明,在面向不同分布的数据集时,相对指数熵指标能够很好地指示出最优分级方法,并且反映出不同分级方法的细小差异,对于地理信息数据分级的评价是有效的。
语种：
中文
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曲线多尺度表达的Head-Tail信息量分割法
作者：
刘鹏程;肖天元;肖佳;艾廷华
期刊：
测绘学报 ,2020年49(7):921-933 ISSN：1001-1595
通讯作者：
Xiao, Jia(jiaxiao@mail.ccnu.edu.cn)
作者机构：
[刘鹏程; 肖天元; 肖佳] School of Urban and Environmental Sciences, Central China Normal University, Wuhan;430079, China;Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province, Central China Normal University, Wuhan;[艾廷华] School of Resource and Environment Sciences, Wuhan University, Wuhan;[刘鹏程; 肖天元; 肖佳] 430079, China<&wdkj&>Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province, Central China Normal University, Wuhan
通讯机构：
[Xiao, J.] S;School of Urban and Environmental Sciences, Central China Normal University, Wuhan, China
关键词：
多尺度表达;傅里叶变换;频域;信息量;Head-Tail分割
摘要：
本文提出一种基于Head-Tail信息量分割的地理要素多尺度表达模型。首先通过傅里叶变换将地理线要素转换为傅里叶描述子,并通过香农信息熵理论计算其频域信息量。然后,按Head-Tail数据分布模式确定地理要素信息量的分界点,并设计函数对各个分界点所对应的傅里叶截断频率进行估计。最后,参考传统方根模型,建立以地理要素频率信息量为基础的信息方根模型,计算与各个地图层次相对应的关键尺度,实现地理要素的层次化多尺度表达。采用等高线及海岸线的数据试验表明,本文所提出的模型能够有效根据设定的比例尺对地理要素进行化简,对不同目标比例尺的简化结果体现出了良好的区分度与层次性。同时,在保证化简结果与原地理要素面积重叠比一致的情况下,本文模型所得到的结果优于传统的简化算法。
语种：
中文
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发展地理学研究进展与展望
作者：
邓祥征;金贵;何书金;王成新;李兆华;...
期刊：
地理学报 ,2020年75(2):226-239 ISSN：0375-5444
作者机构：
[邓祥征; 何书金] Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing;100101, China;Center for Chinese Agricultural Policy, Chinese Academy of Sciences, Beijing;University of Chinese Academy of Sciences, Beijing;100049, China
关键词：
发展地理学;发展路径;可持续发展;区域发展;环境可持续性
摘要：
本文回顾和总结了20世纪以来发展地理学的研究进展,涉及发展地理学内涵和理论、领域和方法及其发展趋势。系统梳理了发展地理学在欠发达国家或地区发展收敛、发达地区或国家生活品质提升过程中的收敛及其路径等研究内容。通过分析国外研究进展,指出了发展地理学在中国的发展条件与学科优势,并着眼于国际学术前沿最新动向与国家宏观战略需求,提出了今后中国发展地理学研究需重点关注的领域。未来发展地理学研究应以可持续发展理论为指引,以提升欠发达地区可持续生计能力与区域绿色发展水平为核心,以构建发展地理学理论和跨学科综合集成研究体系为目标,聚焦区域发展的空间格局、扩散特征与收敛研究,探索出服务于区域经济建设与产业发展的调控政策与科学路径。
语种：
中文
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中国中部六省预期寿命时序加密估算研究
期刊：
地理学报 ,2020年75(10):2269-2280 ISSN：0375-5444
通讯作者：
Gong, Shengsheng(shshgong@mail.ccnu.edu.cn)
作者机构：
[龚胜生; 李畅; 王安丽; 孙攸宁] Key Laboratory for Geographical Process Analysis & Simulation, Hubei Province, College of Urban and Environmental Science, Central China Normal University, Wuhan;430079, China;[龚胜生; 李畅; 王安丽; 孙攸宁] 430079, China
通讯机构：
[Gong, S.] K;Key Laboratory for Geographical Process Analysis & Simulation, China
关键词：
省级预期寿命;时序加密;中国中部六省;拉格朗日插值;线性插值;二次多项式插值
摘要：
年龄组死亡率是利用年龄分组人口数据计算预期寿命的关键参数,而非采样年份的统计年鉴中年龄分组死亡率缺失导致无法计算预期寿命。针对该问题,本文将人口普查数据与统计年鉴数据融合,首次提出一种基于拉格朗日插值的中国省级预期寿命时间序列加强密集度(时序加密)的算法,以解决非采样(即未进行人口普查或1%人口抽样调查)年份省级预期寿命的估算问题。以中国中部六省为例,在所选取年份省级预期寿命估算实验中,绝对精度表明年龄分组人口比例线性插值计算的精度明显高于人口比例抛物线插值和直接插值算法的精度,故为推荐算法。本研究为高时间分辨率下省级预期寿命值的获取提供了一个新的可行思路,为分省较精确地进行预期寿命趋势分析奠定基础。
语种：
中文
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Monitoring vegetation change and their potential drivers in Yangtze River Basin of China from 1982 to 2015
作者：
Xu, Lili
* ;Yu, Guangming
（ ;Tu, Zhenfa;Zhang, Yucui;Tsendbazar, Nandin-Erdene
期刊：
Environmental Monitoring and Assessment ,2020年192(10):1-18 ISSN：0167-6369
通讯作者：
Xu, Lili
作者机构：
[Yu, Guangming; Zhang, Yucui; Xu, Lili; Tu, Zhenfa] Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan 430079, Peoples R China.;[Yu, Guangming; Zhang, Yucui; Xu, Lili; Tu, Zhenfa] Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Peoples R China.;[Tsendbazar, Nandin-Erdene] Wageningen Univ & Res, Lab Geoinformat Sci & Remote Sensing, Droevendaalsesteeg 3, NL-6708 PB Wageningen, Netherlands.
通讯机构：
[Xu, Lili] C;Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Peoples R China.
关键词：
Abrupt change;Gradual change;Restrend;Naturogenic and anthropogenic drivers
摘要：
Monitoring vegetation change and their potential drivers are important to environmental management. Previous studies on vegetation change detection and driver discrimination were two independent fields. Specifically, change detection methods focus on nonlinear and linear change behaviors, i.e., abrupt change (AC) and gradual change (GC). But driver discrimination studies mainly used linear coupling models which rarely concerned the nonlinear behaviors of vegetation. The two diagnoses need be treated as sequential flow because they have inner causality mechanisms. Furthermore, ACs concealed in time series may induce over/under-estimate contributions from human. We chose the Yangtze River Basin of China (YRB) as a study area, first separated ACs from GCs using breaks for additive and seasonal trend method, then discriminated drivers of GCs using optimized Restrend method. Results showed that (1) 2.83% of YRB were ACs with hotspots in 1998 (30.2%), 2003 (10.4%), and 2002 (7.6%); 66.7% of YRB experienced GC with 94.8% of which were positive; and (2) climate induced more area but less dramatic GCs than human activities. Further analysis showed that temperature was the main climate driver to GCs, while human-induced GCs were related to local eco-policies. The widely occurring ACs in 1998 were related to the flooding catastrophe, while the dramatic ACs in sub-basin 12 in 2003 may result from urbanization. This paper provides clear insights on the vegetation changes and their drivers at a relatively long perspective (i.e., 34years). Sequential combination of specifying different vegetation behaviors with driver analysis could improve driver characterizations, which is key to environmental assessment and management in YRB. © 2020, Springer Nature Switzerland AG.
语种：
英文
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Long Term Aquatic Vegetation Dynamics in Longgan Lake Using Landsat Time Series and Their Responses to Water Level Fluctuation
作者：
Tan, Wenxia;Xing, Jindi;Yang, Shao* ;Yu, Gongliang;Sun, Panpan;...
期刊：
Water ,2020年12(8) ISSN：2073-4441
通讯作者：
Yang, Shao
作者机构：
[Xing, Jindi; Jiang, Yan; Tan, Wenxia] Cent China Normal Univ, Coll Urban & Environm Sci, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan 430079, Peoples R China.;[Yang, Shao; Sun, Panpan] Cent China Normal Univ, Sch Life Sci, Wuhan 430079, Peoples R China.;[Yu, Gongliang] Wuhan Univ, Inst Hydrobiol, Key Lab Algal Biol, Wuhan 430072, Peoples R China.
通讯机构：
[Yang, Shao] C;Cent China Normal Univ, Sch Life Sci, Wuhan 430079, Peoples R China.
关键词：
spatial-temporal dynamics;aquatic vegetation;water level fluctuation;Longgan lake;Google Earth Engine
摘要：
Aquatic vegetation in shallow freshwater lakes are severely degraded worldwide, even though they are essential for inland ecosystem services. Detailed information about the long term variability of aquatic plants can help investigate the potential driving mechanisms and help mitigate the degradation. In this paper, based on Google Earth Engine cloud-computing platform, we made use of a 33-year (1987-2019) retrospective archive of moderate resolution Landsat TM, ETM + and OLI satellite images to estimate the extent changes in aquatic vegetation in Longgan Lake from Middle Yangtze River Basin in China using the modified enhanced vegetation index, including emerged, floating-leaved and floating macrophytes. The analysis of the long term dynamics of aquatic vegetation showed that aquatic vegetation were mainly distributed in the western part of the lake, where lake bottom elevation ranged from 11 to 12 m, with average water depth of less than 1 m in spring. The vegetation area variation for the 33-year period were divided into six stages. In years with heavy precipitation, the vegetation area decreased sharply. In the following years, the area normally restored. Aquatic vegetation area had a significant negative correlation with the spring water level and summer water level. The results showed that aquatic vegetation was negatively affected when water depth exceeded 2.5 m in May and 5 m in summer. It is recommended that water depth remain close to 1 m in spring and close to 3 m in summer for aquatic vegetation growth. Our study provide quantitative evidence that water-level fluctuations drive vegetation changes in Longgan Lake, and present a basis for sustainable lake restoration and management. © 2020 by the authors.
语种：
英文
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EFFECTS OF URBANIZATION ON LONG-TERM SURFACE ALBEDO VARIATION USING LANDSAT DATA
作者：
He, Tao* ;Guo, Tianci;Lu, Jun;Song, Danxia
作者机构：
[He, Tao; Lu, Jun; Guo, Tianci] Wuhan Univ, Sch Remote Sensing & Informat Engn, Wuhan 430079, Hubei, Peoples R China.;[Song, Danxia] Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Hubei, Peoples R China.
会议名称：
IEEE International Geoscience and Remote Sensing Symposium (IGARSS)
会议时间：
JUL 28-AUG 02, 2019
会议地点：
Yokohama, JAPAN
会议主办单位：
[He, Tao;Guo, Tianci;Lu, Jun] Wuhan Univ, Sch Remote Sensing & Informat Engn, Wuhan 430079, Hubei, Peoples R China.^[Song, Danxia] Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Hubei, Peoples R China.
会议论文集名称：
IEEE International Symposium on Geoscience and Remote Sensing IGARSS
关键词：
Landsat;surface albedo;urbanization
摘要：
Surface shortwave albedo plays a crucial role in studying urban heat island, local and global radiation budget balance, and climate change. Through modifying the land cover and consequently surface reflectivity, urbanization may lead to substantial changes in surface albedo. China has undergone rapid and massive urbanization during the past 30 years. In order to explore the change of surface shortwave radiation budget caused by urbanization, an accurate and fine resolution surface albedo dataset is needed. Our previous efforts have been devoted to estimating 30m surface albedo from Landsat data, which has been validated with ground measurements distributed globally. In this study, we first examined the estimation accuracy of surface albedo at sites in China, from which the albedo estimation had a bias of 0.005, R2 of 0.717, and root-mean-square-error (RMSE) of 0.053. Then, our albedo algorithm was applied to Landsat data over a few cities in China at different stages of economic development, i.e. Shanghai, Wuhan, and Tai'an. The temporal and spatial change of albedo from 1986 to 2015 and its relationships with land cover change in those study regions were studied. The result shows that urban expansion has brought an increase in albedo in most of these cities, especially in the central district. The rate of albedo increase of Shanghai was the highest among these cities, which is 0.007 per decade, resulting in about 4.65 W/ m2 increase of shortwave upward radiation per decade. Compared to previous research, this study provides more detailed albedo changes of cities at the community scale. The results can also serve as a benchmark for decisionmakings to counteract climate change from future land cover changes and to improve urban microclimate research. © 2019 IEEE.
语种：
英文
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Application of fractional-order derivative in the quantitative estimation of soil organic matter content through visible and near-infrared spectroscopy
作者：
Hong, Yongsheng;Liu, Yaolin;Chen, Yiyun* ;Liu, Yanfang* ;Yu, Lei;...
期刊：
Geoderma ,2019年337:758-769 ISSN：0016-7061
通讯作者：
Chen, Yiyun;Liu, Yanfang
作者机构：
[Hong, Yongsheng; Chen, Yiyun; Liu, Yanfang; Cheng, Hang; Liu, Yaolin; Liu, Yi] Wuhan Univ, Sch Resource & Environm Sci, Wuhan 430079, Hubei, Peoples R China.;[Hong, Yongsheng; Cheng, Hang; Liu, Yaolin; Chen, Yiyun; Liu, Yi; Liu, Yanfang] Wuhan Univ, Key Lab Geog Informat Syst, Minist Educ, Wuhan 430079, Hubei, Peoples R China.;[Yu, Lei] Cent China Normal Univ, Sch Urban & Environm Sci, Wuhan 430079, Hubei, Peoples R China.;[Yu, Lei] Cent China Normal Univ, Key Lab Geog Proc Anal & Simulat Hubei Prov, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Chen, YY; Liu, YF] W;Wuhan Univ, Sch Resource & Environm Sci, Wuhan 430079, Hubei, Peoples R China.
关键词：
Correlation coefficient;Fractional-order derivative;Soil organic matter;Support vector machine;Vis-NIR spectroscopy
摘要：
The spectral preprocessing method has become an integral component of soil analysis through visible and near-infrared (Vis-NIR) spectroscopy. Various spectral pretreatment techniques are applied to improve model accuracy by removing undesired side effects, such as spectral noise, baseline shift, and light scattering, and by accentuating spectral features. Conventional integer-order derivatives (i.e., first and second derivatives), which represent specific cases of fractional-order derivatives (FODs), may neglect some detailed spectral information related to target variables. The objective of this study was to compare the performance of FOD in the estimation of soil organic matter (SOM) with that of conventional first and second derivatives. A total of 258 soil samples (180 for calibration and 78 for validation) were collected from Jianghan Plain, Central China. The reflectance spectra and SOM concentrations of the samples were obtained in the laboratory. Two regression techniques, namely, partial least squares (PLS) and PLS–support vector machine (PLS–SVM), and eight FOD transformation processes for spectral data were combined and compared. Results indicated that as the derivative order increased, the details of the FOD spectra changed and the spectral resolution of reflectance curves improved; the intensity of the spectral signals, however, weakened. The correlation between SOM and FOD spectra was enhanced at some specific wavelengths (e.g., the absolute value of the best one-dimensional correlation coefficient of the 1.25-order derivative spectra could reach 0.65 but that of the original reflectance spectra was only 0.47). In most cases, the PLS–SVM models performed better in SOM estimation than the PLS models. The PLS–SVM model with the 1.25-order derivative spectra exhibited the best model performance and provided the validation R2 and ratio of performance to an interquartile range of 0.79 and 3.03, respectively. FOD offers greater advantages in balancing the spectral resolution and the magnitude of spectral strength than traditional integer-order derivatives. Furthermore, the FOD algorithm has strong application potential in soil Vis-NIR spectroscopy and other types of spectroscopy. © 2018 Elsevier B.V.
语种：
英文
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High-pressure stable phases in mercury azide
作者：
Guo, Shitai;Lin, Jiani;Li, Jianfu* ;Wang, Qinglin;Wu, Hao;...
期刊：
计算材料学(英文) ,2019年169:109147 ISSN：2057-3960
通讯作者：
Li, Jianfu;Wang, Xiaoli
作者机构：
[Guo, Shitai] Wuhan Univ Technol, Sch Resource & Environm Engn, Wuhan 430070, Hubei, Peoples R China.;[Zhu, Hongyang; Lin, Jiani; Li, Jianfu; Wang, Xiaoli; Wang, XL; Guo, Shitai] Linyi Univ, Sch Phys & Elect Engn, Linyi 276005, Shandong, Peoples R China.;[Wang, Qinglin] Liaocheng Univ, Shandong Key Lab Opt Commun Sci & Technol, Sch Phys Sci & Informat Technol, Liaocheng 252059, Shandong, Peoples R China.;[Wu, Hao] Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Li, JF; Wang, XL] L;Linyi Univ, Sch Phys & Elect Engn, Linyi 276005, Shandong, Peoples R China.
关键词：
High pressure;Mercury azide;Polymeric nitrogen
摘要：
Exploring the bonding properties and polymerization mechanism of the polymer phases of nitrogen-rich compounds is one of the goals of high-pressure research. Considering first-principles calculations, a particle swarm optimization structure search method has been used to study the structural evolution behavior of nitrogen in HgN3 up to 200 GPa. Three new phases with P-1, P21/m, and P-1 structures at pressures of 38 GPa, 125 GPa, and 148 GPa are identified for the first time. The theoretical calculations show that the two P-1 structures are dynamically stable at 50 GPa and 200 GPa. In these two phases, the nitrogen atoms form an infinite one-dimensional zigzag chain and connected N6 ring, respectively. Two stable structures have semiconductor properties throughout the stable pressure range, primarily due to sp2 hybridization of nitrogen atoms. Our studies provide a theoretical basis for the synthesis of polymeric nitrogen in high-pressure experiments and indicate the direction for future studies of mercury azide. © 2019 Elsevier B.V.
语种：
英文
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X-ray fluorescence and visible near infrared sensor fusion for predicting soil chromium content
作者：
Xu, Dongyun;Chen, Songchao;Rossel, R. A. Viscarra;Biswas, Asim;Li, Shuo;...
期刊：
Geoderma ,2019年352:61-69 ISSN：0016-7061
通讯作者：
Shi, Zhou
作者机构：
[Shi, Zhou; Zhou, Yin; Xu, Dongyun] Zhejiang Univ, Coll Environm & Resource Sci, Inst Agr Remote Sensing & Informat Technol Applic, Hangzhou 310058, Zhejiang, Peoples R China.;[Chen, Songchao] INRA, Unite InfoSol, F-45075 Orleans, France.;[Rossel, R. A. Viscarra] Curtin Univ, Sch Mol & Life Sci, Bentley, WA 6102, Australia.;[Biswas, Asim] Univ Guelph, Sch Environm Sci, 50 Stone Rd, Guelph, ON N1G 2W1, Canada.;[Li, Shuo] Cent China Normal Univ, Coll Urban & Environm Sci, Wuhan 430079, Hubei, Peoples R China.
通讯机构：
[Shi, Zhou] Z;Zhejiang Univ, Coll Environm & Resource Sci, Inst Agr Remote Sensing & Informat Technol Applic, Hangzhou 310058, Zhejiang, Peoples R China.
关键词：
Granger–Ramanathan averaging;Outer-product analysis;Proximal soil sensor;Soil spectroscopy
摘要：
Anthropogenic activities, such as sewage irrigation and application of pesticides and fertilizers, are the main cause of chromium (Cr) contamination in agricultural soils. Cr contamination reduces soil quality and threatens environmental and human health. Conventional Cr measurement methods, although accurate, involve complex sample processing steps and sophisticated laboratory analysis, which are time-consuming, costly, and often environmentally unfriendly. X-ray fluorescence (XRF) and visible near-infrared (vis–NIR) spectroscopy have been recognized as alternatives to measure soil heavy metal contamination in a cheap, fast, non-destructive, and environmentally conscious manner. In this study, 301 paddy soil samples from Fuyang, Zhejiang Province, China were used to explore the feasibility and effectiveness of XRF and vis–NIR spectra separately and in combination for estimating the soil Cr content. Two strategies, including outer-product analysis (OPA) and Granger–Ramanathan averaging (GRA), were used to combine the spectra and spectral models, respectively, from the two instruments (sensor fusion). Partial least-squares regression (PLSR) was used to train the models using a single sensor (XRF or vis-NIR spectra) and OPA fused spectra. Fifty boot straps were used to assess the uncertainty of the predictions for the aforementioned models. The results indicated that XRF spectra performed better than vis–NIR spectra for predictions of Cr content, with a Lin's concordance correlation coefficient (ρc) of 0.83, a root mean square error (RMSE) of 8.80, and a ratio of prediction derivation (RPD) of 1.75. Sensor fusion by OPA gave the highest prediction accuracy with a ρc of 0.90, RMSE of 6.80, and RPD of 2.30. The sensor fusion by GRA gave similar results with a ρc of 0.88, RMSE of 7.40, and RPD of 2.13. The predictions using both methods (OPA and GRA) were acceptable when considering the standard deviation of differences (SDD = 4.23). This suggests that OPA and the GRA sensor fusion methods are efficient and accurate for rapid measurement of Cr and provide a way forward for using these technologies for fast, sensor-based soil characterization. © 2019 Elsevier B.V.
语种：
英文
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