Remote sensing of 10 years changes in the vegetation cover of the northwestern coastal land of Red Sea, Saudi Arabia

Abstract

Accurate and up to date land use and land cover (LU/LC) changes information is the main source to understanding and assessing the environmental outcomes of such changes and is important for development plans. Thus, this study quantified the outlines of land cover variation of 10-years in the northwestern costal land of the Red Sea, Saudi Arabia. Two different supervised classification algorithms are visualized and evaluated to preparing a policy recommendation for the proper improvements towards better determining the tendency and the proportion of the vegetation cover changes. Firstly, to determine present vegetation structure of study area, 78 stands with a size of 50 × 50 m were analysed. Secondly, to obtain the vegetation dynamics in this area, two satellite images of temporal data sets were used; therefore, SPOT-5 images were obtained in 2004 and 2013. For each data set, four SPOT-5 scenes were placed into approximately 250-km intervals to cover the northwestern coastal land of the Red Sea. Both supervised and non-supervised cataloguing methods were attained towards organise the study area in 4-major land cover classes through using 5 various organizations algorithms. Approximately 900 points were evenly distributed within each SPOT-5 image and used for assessment accuracy. The floristic composition exhibits high diversity with 142 species and seven vegetation types were identified after multivariate analysis (VG I: Acacia tortilis - Acacia ehrenbergiana , VG II: Acacia tortilis - Stipagrostis plumosa, VG III: Zygophyllum coccineum - Zygophyllum simplex , VG IV: Acacia raddiana-Lycium shawii-Anabasis setifera , VG V: Tamarix aucheriana-Juncus rigidus , VG VI: Capparis decidua - Zygophyllum simplex and VG VII: Avicennia marina - Aristida adscensionis ) and ranged between halophytic vegetation on the coast to xerophytic vegetation with scattered Acacia trees inland. The dynamic results showed rapid, imbalanced variations arises between 3-land cover classes (areas as urban, vegetation and desert). However, these findings shall serve as the baseline data for the design of rehabilitation programs that conserve biodiversity in arid regions and form treasured resources for an urban planner and decision makers to device bearable usage of land and environmental planning.

Do Spatially Structured Soil Variables Influence the Plant Diversity in Tabuk Arid Region, Saudi Arabia?

“…The variability in the number of recorded species reflects the remarkable plant diversity in this region [44,45]. Climate changes, as well as several anthropogenic activities, are threatening the natural diversity of plants in this region [46,47].…”

Ecology of inland sand dunes “nafuds” as a hyper-arid habitat, Saudi Arabia: Floristic and plant associations diversity

“…For example, Capparis spinosa and Pulicaria undulata have a similar evenness cover and are co-dominant species. Moreover, in the lower plain habitats, herbaceous and sub-shrub species with shallow adventitious fine roots are dominant, while woody shrubs are absent due to the hardpan soil substrate ( Abbadi and El-Sheikh, 2002 , Alharthi et al, 2020 , Blot and Hajar, 1994 , Valentini et al, 2020 ).…”

“…The primary adaptation of dune plants to moving sand is the rapid elongation of stems and roots to keep reproductive and photosynthetic organs above the accumulated sand level. Such elongation typically begins when the plants are seedlings and continues as they grow ( Alharthi et al, 2020 , Bowers, 1982 , Elmefregy and El-Sheikh, 2020 , El-Sheikh et al, 2010 , Mandaville, 1998 , Vincent, 2008 ). Dunes that support enough plant growth and cover will be stabilized by root and stem elongation, and thus, sand movement will cease.…”

Volumetric Quantification of Flash Flood Using Microwave Data on a Watershed Scale in Arid Environments, Saudi Arabia

“…One common disaster in the arid region is flash floods, which is influenced by less vegetation and an abundance of loose materials [6]. The loose sediment materials and lack of cohesivity on the soils can cause extreme sediment fluxes during a flash flood in an arid region [7,8]. In the arid region, sometimes water caused by extreme rainfall cannot penetrate easily into the ground due to impermeable rock (e.g., caliche) and causes high runoff water [9][10][11].…”