Spatio-Temporal Dynamics of Environmental Status Based on a Remote Sensing Ecological Distance Index (RSEDI) in the Oases of Hexi Corridor in Northwest China

L’objectif de cette étude est d’établir à partir de la télédétection et des SIG, la dynamique spatio-temporelle des terres de cultures et d’explorer les futurs possibles de l’occupation du sol dans trois communes rurales de la région de Thiès (Fandène, Notto Diobass et Taiba Ndiaye). Une classification multidate des images landsat (1988, 2002 et 2014) a permis de quantifier les changements d’occupation des terres. Les résultats montrent que les zones de culture de Fandène sont passées entre 1988 et 2014 de 62% à 52% de la superficie totale de la commune. A l’opposée la commune de Taiba Ndiaye connait une expansion des zones de culture entre ces deux dates. Les changements enregistrés à Notto sont négligeables. Les simulations, faites sur la base des probabilités pour que la valeur d’une cellule i reste inchangée ou prenne la valeur d’une autre cellule j à l’horizon 2035, révèlent que les terres de culture de Fandène ont 69% de probabilité d’évoluer vers d’autres classes d’occupation du sol. ABSTRACT The objective of this study is to quantify from remote sensing and GIS the spatio temporal dynamics of cultivated land and explore possible futures of land use in three rural municipalities of Thies (Fandene, Notto Diobass, and Taiba Ndiaye). A multidate classification Landsat images (1988, 2002 et 2014) was used to quantify change in land cover. The results show that between 1988 and 2014 Fandene cropping areas have passed from 62% to 52% of the total area. At the opposite the commune of Taiba Ndiaye has known an expansion of cropping areas between these two dates. Minor changes are noted in Notto district. Simulations carried out on the basis of probabilities for a unit i to stay in the same cell or to be converted to another unit j in 2035, reveals that the probability for a cultivated land unit to be transformed into a another land cover category is high in Fandene (69 %).

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Tracking spatio-temporal dynamics of POC sources in eutrophic lakes by remote sensing

Water Research ◽

10.1016/j.watres.2019.115162 ◽

2020 ◽

Vol 168 ◽

pp. 115162 ◽

Cited By ~ 2

Author(s):

Jie Xu ◽

Shaohua Lei ◽

Shun Bi ◽

Yunmei Li ◽

Heng Lyu ◽

...

Keyword(s):

Remote Sensing ◽

Temporal Dynamics ◽

Eutrophic Lakes ◽

Spatio Temporal

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Remote Sensing of Agricultural Greenhouses and Plastic-Mulched Farmland: An Analysis of Worldwide Research

Remote Sensing ◽

10.3390/rs12162649 ◽

2020 ◽

Vol 12 (16) ◽

pp. 2649

Author(s):

Rafael Jiménez-Lao ◽

Fernando J. Aguilar ◽

Abderrahim Nemmaoui ◽

Manuel A. Aguilar

Keyword(s):

Biological Sciences ◽

Remote Sensing ◽

Temporal Dynamics ◽

Research Topic ◽

Relative Significance ◽

Main Research ◽

The Usa ◽

The Subject ◽

Spatio Temporal ◽

Number Of Publications

The total area of plastic-covered crops of 3019 million hectares has been increasing steadily around the world, particularly in the form of crops maintained under plastic-covered greenhouses to control their environmental conditions and their growth, thereby increasing production. This work analyzes the worldwide research dynamics on remote sensing-based mapping of agricultural greenhouses and plastic-mulched crops throughout the 21st century. In this way, a bibliometric analysis was carried out on a total of 107 publications based on the Scopus database. Different aspects of these publications were studied, such as type of publication, characteristics, categories and journal/conference name, countries, authors, and keywords. The results showed that “articles” were the type of document mostly found, while the number of published documents has exponentially increased over the last four years, growing from only one document published in 2001 to 22 in 2019. The main Scopus categories relating to the topic analyzed were Earth and Planetary Sciences (53%), Computer Science (30%), and Agricultural and Biological Sciences (28%). The most productive journal in this field was “Remote Sensing”, with 22 documents published, while China, Italy, Spain, USA, and Turkey were the five countries with the most publications. Among the main research institutions belonging to these five most productive countries, there were eight institutions from China, four from Italy, one from Spain, two from Turkey, and one from the USA. In conclusion, the evolution of the number of publications on Remote Sensing of Agricultural Greenhouses and Plastic-Mulched Farmland found throughout the period 2000–2019 allows us to classify the subject studied as an emerging research topic that is attracting an increasing level of interest worldwide, although its relative significance is still very limited within the remote sensing discipline. However, the growing demand for information on the arrangement and spatio-temporal dynamics of this increasingly important model of intensive agriculture is likely to drive this line of research in the coming years.

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Limitations in identifying the equilibrium-line altitude from the optical remote-sensing derived snowline in the Tien Shan, China

Journal of Glaciology ◽

10.3189/2014jog13j221 ◽

2014 ◽

Vol 60 (224) ◽

pp. 1093-1100 ◽

Cited By ~ 13

Author(s):

WU Yuwei ◽

HE Jianqiao ◽

GUO Zhongming ◽

Chen Anan

Keyword(s):

Remote Sensing ◽

Warm Season ◽

Northwest China ◽

Tien Shan ◽

Equilibrium Line ◽

Optical Remote Sensing ◽

Large Area ◽

Equilibrium Line Altitude ◽

Spatio Temporal

AbstractOptical remote-sensing derived end-of-summer snowline altitude (SLA) has long been employed on glaciers as an indicator of the equilibrium-line altitude (ELA). In the Tien Shan, northwest China, both accumulation and ablation of glaciers occur mainly in the warm season, making it difficult to obtain the representative snowline (highest snowline) in the area. The high spatio-temporal resolution of HJ-1 satellite images enables the highest snowline to be acquired. In this paper, we compare image-derived SLA and measured in situ ELA for two adjacent glaciers in the Tien Shan over the period 2009–10. Results indicate that (1) in 2009, there was a substantial difference between SLA and ELA on one glacier, suggesting inconsistent applicability in using SLA to identify ELA over a large area; and (2) in 2010, an intense ablation year, the field-data-derived ELA surpassed the glacier peak. In this situation, there is no theoretical relationship between SLA and ELA, and the image-derived snowline actually indicates the boundary between ice and firn from previous years. In summary, errors will arise from the discrepancies between individual glaciers and from intensive ablation when using SLA to identify ELA over a large area.

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