scholarly journals Evolution Du Couvert Végétal Naturel Au Niveau Des Massifs Forestiers De Mallalyine Et Taghramt (Rif Occidental Du Maroc)

2018 ◽  
Vol 14 (24) ◽  
pp. 19
Author(s):  
Mhammad Houssni ◽  
Hassan Ennouni ◽  
Abdessalam Ouallali ◽  
Jalal Kassout ◽  
Mohamed El Mahroussi ◽  
...  

This work presents the results of a cartographic study of the spatiotemporal evolution of vegetation cover in the forest areas of Mallalyine and Taghramt in the western Rif. It is based on a field survey and the photointerpretation of aerial photographs taken in 1986 and Google Earth images from 2013 (a period of twenty-seven years). Our study reports on the current state of degradation of the vegetation cover in the forests of Mallalyine and Taghramt. We have produced two land use maps showing how high and low formations as well as scrub have regressed by 62, 70 and 49 percent, respectively, between 1986 and 2013, while non-forested land and reforestation increased respectively by 26.3 and 1.53 percent relative to the area covered in 1986. The main factors contributing to the decline of vegetation cover are: deforestation (35 offenses registered every year with a degraded area of about 15 ha / year), clearing (27 offenses per year with an European Scientific Journal August 2018 edition Vol.14, No.24 ISSN: 1857 – 7881 (Print) e - ISSN 1857- 7431 20 affected area of about 20 ha / year), overgrazing (10 offenses of illegal grazing per year with a degraded area of about 12 ha / year), forest fires (4 to 5 fires per year with a degraded area of about 50 ha / year). In addition to these factors, we find increasing water scarcity.

2009 ◽  
Vol 24 (1) ◽  
pp. 1
Author(s):  
Mujiyo Mujiyo

<span>The research has aims to know ; (1) the velocity of function displace of the rice field to the non rice field during year period 2000, 2004 and 2008, (2) change grain product during year period 2000, 2004 and 2008, and (3) the relationship between the velocity of function displace of the rice field to the non rice field and the grain production during year period 2000, 2004 and 2008. Function displace of the rice field in the Kebabakkramat District known by determining the wide of each land use type in the appointed year, and then comparing it with data in the next year. The first mapping was based on the Map of Rupa Bumi Bakosurtanal which made in 2000. The second mapping was based on the image QUICK BIRD 2004 which published in the internet media Google Earth. And the third mapping determined by field survey in the 2008. Result of the research shows that ; (1) rice field in the Kebakkramat District along period 2000 until 2008 had function displace, 2.571,89 ha (2000) decreased to become 2.153,33 ha (2004), and decreased again to become 2.128,11 ha (2008), (2) grain production in the Kebakkramat District along period 2000 until 2007 shows increasing trend, 39.880 ton (2000) increased to become 40.631 ton (2003), but decreased to become 35.354 ton (2004), and increased again to become 43.062 ton (2007), (3) although wide of the rice field decreased, but the grain production increased, because increasing its land productivity caused by continuity of the rice field intensification program.</span>


2021 ◽  
Author(s):  
Camilla Santos ◽  
Leonardo Dantas Martins ◽  
Kenia Sousa da Cruz ◽  
Jonas Otaviano Praça de Souza

&lt;p&gt;Rivers on semiarid landscapes typically are characterised by sandy geomorphic units and riverbanks, a natural factor that enhances lateral mobility. Vegetation cover is a crucial factor on lateral instability due to its impact on riverbank and geomorphic units erosion resistance. Nevertheless, riparian vegetation on intermittent and ephemeral channels show growing patterns directly affect by the flow temporality, that controls the water availability. Extended dry intervals hinder the succession ecological on geomorphic units, like bars and islands, and riverbanks and retard the growing process. This work analysed the effects of hydrological changes, caused by one water transfer project, on the bio-geomorphological patterns on riverbanks of a main intermittent river of Brazilian Drylands. Flow data series was used to understand the hydrological pattern changes; Google Earth images and UAV surveys to analyse the vegetation and riverbank behaviour from 2008 to 2020.&amp;#160; Lastly, the identification of riverbank material resistance was based on sedimentology analysis. &amp;#160;The water transfer Project PISF (Projeto de Integra&amp;#231;&amp;#227;o do S&amp;#227;o Francisco), operating since 2017 March, increase the average flow days from 137,5 to 260/300 days and decreasing the continuous dry period from 200 to 30/45 days. The impact on average annual discharge was slightest, whereas the average water transfer volume was 3m&lt;sup&gt;3&lt;/sup&gt;/s. It is essential to highlight the short period of data posterior to the water transfer and the non-regulatiry of water volume transferred; what limits the temporal representativity of the results. There were different types, and level of impacts depending on the river reach characteristics. However, in general, the longer flow permanence increases riparian vegetation density, vertical incision, and lateral stability. Riparian vegetation cover increase, from 20% to 100% on the 9 reaches analysed, across the entire channel, including bedrock reaches, with riverbanks having some rock outcrops percentage. The main changes were on sand bed reaches, that used to have, before 2017, a dynamic braiding pattern, without a clear main incised channel and thalweg shifting. Afterwards, the flow permanence, due to the water transfer project, enabled herbaceous stratus temporal continuity, contributing to surface stability and progressive bushes/trees cover growing. Lastly, the increase in lateral stability, mainly on thalweg position, facilitates the vertical incision on the sand bed reaches, representing 85% of this channel. As a secondary impact, there were necessary, to the road network, built floodway crossings at several points, which changes the channel morphology and the (dis)connectivity process. It can generate distinct channel position and morphology changes causing water and sediment retention upstream and erosion downstream. Lastly, there were slight differences in textural characteristics on riverbanks and geomorphic units, with a rise in fine sediment on the most vegetated areas/units. This analysis reveals that a fast response of riparian vegetation and sand bed reaches morphology, affecting the bio-geomorphological process and all environmental dynamic. It points to fundamental elements which need monitoring after hydrological changes, especially to intermittent and ephemeral rivers.&lt;/p&gt;


2021 ◽  
Vol 25 (9) ◽  
pp. 30-37
Author(s):  
N.N. Sliusar ◽  
A.P. Belousova ◽  
G.M. Batrakova ◽  
R.D. Garifzyanov ◽  
M. Huber-Humer ◽  
...  

The possibilities of using remote sensing of the Earth data to assess the formation of phytocenoses at reclaimed dumps and landfills are presented. The objects of study are landfills and dumps in the Perm Territory, which differed from each other in the types and timing of reclamation work. The state of the vegetation cover on the reclaimed and self-overgrowing objects was compared with the reference plots with naturally formed herbage of zonal meadow vegetation. The process of reclamation of the territory of closed landfills was assessed by the presence and homogeneity of the vegetation layer and by the values of the vegetation index NDVI. To identify the dynamics of changes in the vegetation cover, we used multi-temporal satellite images from the open resources of Google Earth and images in the visible and infrared ranges of the Landsat-5/TM and Landsat-8/OLI satellites. It is shown that the data of remote sensing of the Earth, in particular the analysis of vegetation indices, can be used to assess the dynamics of overgrowing of territories of reclaimed waste disposal facilities, as well as an additional and cost-effective method for monitoring the restoration of previously disturbed territories.


2020 ◽  
Vol 26 (7) ◽  
pp. 17-32
Author(s):  
F. Enikeev ◽  

Based on the methods of remote identification and spatial fixation of glacial relief forms with their subsequent geomorphological analysis, the lower boundary of the chionosphere, the glacier feeding areas, boundaries and glacier parameters of the maximum phase of the Last Glacial Maximum glaciers (MIS 2) of the mountainous regions of Southern Baikal region were established and a paleogeographic map was constructed. The object of this study was the dynamics of exogenous processes during the development of the permafrost zone in the Southern Baikal region. The subject of the study is the glacial landforms of the Late Neopleistocene of the Khamar-Daban ridge. Glaciers were reconstructed using absolute marks of destructive and accumulative traces using topographic maps, aerial photographs and satellite images. Paleogeographic constructions were carried out using computer programs Google Earth Pro and SAS. Planet release. The final generalization of the primary material was carried out on a topographic basis on a scale of 1:500,000. The results obtained made it possible to establish the depression of the snow boundary at the maximum of the last cooling at 1300…1400 m in relation to the current climatic and to reveal the features of deformation of the lower border of the chionosphere. The reconstruction of the paleogeographic situation showed the spread of simple and complex (dendritic) types of mountain-valley glaciers, as well as mesh and mountain-glaciation glaciers in some parts of the mountain top. It was established that in the region of the maximum depression of the snowy border, some glaciers reached the coast of Lake Baikal, which could contribute to dilution of secondary aureoles and the displacement of placer mineral deposits. On the southern slope of the Khamar-Daban ridge, the snow boundary passed at an altitude of 1800…2200 m, and glaciation was limited to the development of only circus and circus-valley glaciers of small sizes, contributing to the formation of placers far removed from indigenous sources


Author(s):  
Dimitris Kaimaris ◽  
Petros Patias ◽  
Olga Georgoula

The interpretation of photos and the processing of Google Earth imagery which allowed the “random” discovery, as a result of a non-systematical research, of a numerous marks of buried constructions in the wide area of the city of Larisa (Thessaly, Greece) is presented in this project. Additional data as aerial photographs over time, satellite images and the digital terrain model of the same area has been used. From the numerous marks, this project mainly focuses on three positions where the positive marks (soilmarks or/and cropmarks), circular or/and linear, reveal on a satisfying level covered construction of great dimensions. The ongoing research activity of the editorial team along with this research highlights the advantages of using Google Earth imagery in an attempt to “random” mark of unknown covered constructions, or, in the frame of a systematic survey of aerial and remote sensing archaeology, as additional and not exclusive source of information.


2019 ◽  
Vol 16 ◽  
pp. 00049
Author(s):  
Marina Tsyrenova ◽  
Evgenia Pyzhikova ◽  
Elena Vasilyeva

The article presents the results of a research study of anthropogenic affects of gold mining on forest landscapes in Northern Transbaikalia, Russia and processes of natural reclamation of vegetation cover of the disturbed areas. The study area is located northwest of the Maliy Amalat River, which flows along the Vitim Plateau; in the floodplains of its two tributaries the Aunik River and the Bagdarin River. It is an area where a large number of alluvial gold deposits have been discovered. Some of these deposits are currently being developed, some have already been explored, and some have been abandoned. The authors consider the current state of vegetation cover in a key area of the Amalat River basin, near villages of Malovsky and Bagdarin. The problem of natural resources development and conservation is becoming extremely important for the area under study because open-pit gold mining methods that are used here drastically change the environment and affect water, land and forest resources.


2019 ◽  
Vol 11 (12) ◽  
pp. 1505 ◽  
Author(s):  
Heng Zhang ◽  
Anwar Eziz ◽  
Jian Xiao ◽  
Shengli Tao ◽  
Shaopeng Wang ◽  
...  

Accurate mapping of vegetation is a premise for conserving, managing, and sustainably using vegetation resources, especially in conditions of intensive human activities and accelerating global changes. However, it is still challenging to produce high-resolution multiclass vegetation map in high accuracy, due to the incapacity of traditional mapping techniques in distinguishing mosaic vegetation classes with subtle differences and the paucity of fieldwork data. This study created a workflow by adopting a promising classifier, extreme gradient boosting (XGBoost), to produce accurate vegetation maps of two strikingly different cases (the Dzungarian Basin in China and New Zealand) based on extensive features and abundant vegetation data. For the Dzungarian Basin, a vegetation map with seven vegetation types, 17 subtypes, and 43 associations was produced with an overall accuracy of 0.907, 0.801, and 0.748, respectively. For New Zealand, a map of 10 habitats and a map of 41 vegetation classes were produced with 0.946, and 0.703 overall accuracy, respectively. The workflow incorporating simplified field survey procedures outperformed conventional field survey and remote sensing based methods in terms of accuracy and efficiency. In addition, it opens a possibility of building large-scale, high-resolution, and timely vegetation monitoring platforms for most terrestrial ecosystems worldwide with the aid of Google Earth Engine and citizen science programs.


2020 ◽  
Vol 12 (16) ◽  
pp. 2531
Author(s):  
Efraín Duarte ◽  
Juan A. Barrera ◽  
Francis Dube ◽  
Fabio Casco ◽  
Alexander J. Hernández ◽  
...  

Current estimates of CO2 emissions from forest degradation are generally based on insufficient information and are characterized by high uncertainty, while a global definition of ‘forest degradation’ is currently being discussed in the scientific arena. This study proposes an automated approach to monitor degradation using a Landsat time series. The methodology was developed using the Google Earth Engine (GEE) and applied in a pine forest area of the Dominican Republic. Land cover change mapping was conducted using the random forest (RF) algorithm and resulted in a cumulative overall accuracy of 92.8%. Forest degradation was mapped with a 70.7% user accuracy and a 91.3% producer accuracy. Estimates of the degraded area had a margin of error of 10.8%. A number of 344 Landsat collections, corresponding to the period from 1990 to 2018, were used in the analysis. Additionally, 51 sample plots from a forest inventory were used. The carbon stocks and emissions from forest degradation were estimated using the RF algorithm with an R2 of 0.78. GEE proved to be an appropriate tool to monitor the degradation of tropical forests, and the methodology developed herein is a robust, reliable, and replicable tool that could be used to estimate forest degradation and improve monitoring, reporting, and verification (MRV) systems under the reducing emissions from deforestation and forest degradation (REDD+) mechanism.


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