Wyniki wyszukiwania - Biblioteka Nauki

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

3 2022

Znaleziono wyników: 3

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

Meteorological Drought Assessment in the Ziz Watershed (South East of Morocco)

100%

Dafouf S. , Lahrach A. , Tabyaoui H. , El Hafyani M. , Benaabidate L.

Ecological Engineering & Environmental Technology

2022

tom Vol. 23, iss. 6

243--263

In the face of climate change, drought monitoring and characterisation is indispensable in arid and semi-arid areas. This paper represents a metrological drought assessment in the Ziz watershed located in south-eastern Morocco, through the application of four meteorological indices: rainfall anomaly index (RAI), percentage of normal index (PNI), standardized precipitation index (SPI), z-score index (ZSI). Based on rainfall data series from four stations over a time scale of 37 years (from 1983), also taking into account the relationship between these indices. The analysis of the rainfall series indicates a variability in its spatio-temporal distribution. However, the calculated drought indices indicate that the Ziz basin has experienced drought periods with their different classifications between 1983–2019, noting that the years 1986 and 2001 were dry to extremely dry in all stations of the basin. Thus, the results highlight a strong correlation between the four indices (r ≥ 0.967).

Modelling and Mapping of Soil Organic Matter in Doukkala Plain, Moroccan Semi-Arid Region

100%

Bel-Lahbib S. , Namr K. I. , El Hafyani M. , Al Masmoudi Y. , Essahlaoui A.

tom Vol. 23, iss. 5

188--197

The Doukkala plains one of the largest irrigated areas in Morocco with a very important agricultural potential. With the integration of new technologies in agriculture, the plain has been subjected to intensive agriculture which has negative impacts on soil quality especially the soil organic matter loss. Therefore, the objective of this study is to combine remote sensing and modelling for monitoring of organic matter content. The obtained results showed that all the examined models showed satisfactory results in the prediction of organic matter with a coefficient of determination R2 ranging from 0.58 to 0.71 and the Root Mean Square Error (RMSE) varied 0.25 and 0.26%. Based on the findings, we can infer that this approach is both efficient and valid for modelling and mapping soil organic matter and may moreover be applied for other areas with same characteristics.

Diachronic mapping and evaluation of soil erosion rates using RUSLE in the Bouregreg River Watershed, Morocco

86%

Moudden F. , El Hafyani M. , El Ouali A. , Roubil A. , El Ouali A. , Essahlaoui A. , Brouziyne Y.

Journal of Water and Land Development

2022

tom no. 53

86--99

Soil erosion has been severely affecting soil and water resources in semi-arid areas like the Mediterranean. In Morocco, this natural process is accelerated by anthropogenic activities, such as unsustainable soil management, overgrazing, and deforestation. With a drainage area of 395,600 ha, the Bouregreg River Watershed extends from the Middle Atlas Range (Jebel Mtourzgane) to the Sidi Mohamed Ben Abdellah (SMBA) dam reservoir south-east of Rabat. Its contrasted eco-geomorphological landscapes make it susceptible to unprecedented soil erosion due to climate change. Resulting changes in erosive dynamics led to huge amounts of solid loads transported to the catchment outlet and, thus, jeopardised the SMBA dam lifespan due to siltation. The research aims to quantify the average annual soil losses in this watershed using the Revised Universal Equation of Soil Losses (RUSLE) within a GIS environment. To highlight shifts in land use/land cover patterns and their effects on erosional severity, we have resorted to remote sensing through two Landsat 8 satellite images captured in 2004 and 2019. The C factor was combined with readily available local data regarding major erosion factors, e.g. rainfall aggressiveness (R), soil erodibility (K), topography (LS), and conservation practices (P). The helped to map the erosion hazard and determine erosion prone areas within the watershed where appropriate water and conservation measures are to be considered. Accordingly, from 2004 to 2019, average annual soil losses increased from 11.78 to 18.38 t∙ha-1∙y-1, as the watershed area affected by strong erosion (>30 t∙ha-1∙y-1) evolved from 13.57 to 39.39%.