Modeling of the current and future potential distribution of Atlas cedar (Cedrus atlantica) forests revealed shifts in the latitudinal, longitudinal and altitudinal range towards more humid conditions

Environmental forcing affects biodiversity in some parts of the biosphere where many sensitive species, including endemic and rare species, respond through changes in their geographical distribution. Modelling of spatial dynamics of species is crucial to advance our understanding of species’ adaptive behaviour and sensitivity to environmental changes and forcings. The present study aimed at assessing suitable habitats of the Atlas cedar (Cedrus atlantica) in North Algeria for the current period (1990–2000) and predicting its future range in 2050 and 2070, following climate warming scenarios. The Maximum Entropy (MaxEnt) model was used to model the present and future potential distribution of Atlas cedar forests. A total of 1,328 occurrence records obtained from field surveys and 50 environmental variables were used. These variables included 19 climatic variables (WorldClim database), 21 edaphic proprieties (SoilGrids database), and 10 topographic traits (retrieved from a 30 m digital elevation model). MaxEnt showed high predictive power with a significant value of Area Under Curve (AUC=0.988). Potential distribution of Cedrus atlantica forests for the present period was confined to mountain areas (predicted potential range size = 2089 km²). Environmental factors with the highest percentage of contribution included: soil total nitrogen (22.2%), elevation (20.5%), mean temperature of the most humid quarter ‘Bio8’ (18.8%), slope (12.9%), soil total carbon (10.3%), and precipitation of the driest month ‘Bio14’ (3.4%). The species range is expected to reduce significantly under future climate change scenarios (decline of about 70.4–80.6% of its current potential distribution), with a shift towards more humid conditions, in this case to the north and east towards more humid climates and mesic habitats. The predicted shifts in the altitude gradient follow in the direction of higher elevations, with the disappearance of cedar forests at low altitudes. This indicates that the identified Atlas cedar refugia resulting from climate change are determined by humidity. Our findings provide information on the magnitude of environmental forcings that seriously threaten Cedrus atlantica forests in drought-prone areas in North Africa. It is therefore necessary to implement effective strategies to preserve and protect more sensitive forests

Spatio-Temporal Variation Patterns of Bird Community in the Oasis Ecosystem of the North of Algerian Sahara

The spatial and temporal variation patterns of birds were investigated in the Oasis ecosystem of the North of Algeria Sahara. This contribution aimed to investigate the poorly studied bird fauna of Bousaâda oasis. The direct observation method was used for bird counts, adopted only during the breeding period. A total of 53 species of birds from 29 families and 16 orders were assessed in the different habitats of the Oasis (palm, fruit trees and, cultivated crops). The Passeriformes order was the most abundant represented by 35 species and 16 families. The relative abundance and species richness were recorded during our study period over different seasons and thought that whole surveyed stations represent all the oasis habitats. The Boussaâda oasis holds 18 resident-breeder species and is a transit zone for many migratory birds 14 and 10 species for summer and winter migrants respectively) and11 occasional visitor ones. These results confirmed the positive effects of stations and seasons on the richness and abundance of birds of Bousaâda oasis

New Record of Two Rodent Species from Khenchela Region (East of Algeria)

Mus spretus is endemic to the Mediterranean region and Jaculus orientalis is only found in North Africa and Saudi Arabia. Their presence in Algeria was previously evidenced in other studies, the present paper focuses on the recent discovery of the Jaculus orientalis Erxleben, 1777 and Mus spretus Lataste, 1883 in a new locality of the East of Algeria, in Khenchela region (Aurès Mountain), based on weight and external measurements. The sampling period took four months between April and July 2019. This observation will enrich the knowledge of Algerian Rodents fauna in general and of Khenchela in particular

Spatio-Temporal Variation Patterns of Bird Community in the Oasis Ecosystem of the North of Algerian Sahara

The spatial and temporal variation patterns of birds were investigated in the Oasis ecosystem of the North of Algeria Sahara. This contribution aimed to investigate the poorly studied bird fauna of Bousaâda oasis. The direct observation method was used for bird counts, adopted only during the breeding period. A total of 53 species of birds from 29 families and 16 orders were assessed in the different habitats of the Oasis (palm, fruit trees and, cultivated crops). The Passeriformes order was the most abundant represented by 35 species and 16 families. The relative abundance and species richness were recorded during our study period over different seasons and thought that whole surveyed stations represent all the oasis habitats. The Boussaâda oasis holds 18 resident-breeder species and is a transit zone for many migratory birds 14 and 10 species for summer and winter migrants respectively) and11 occasional visitor ones. These results confirmed the positive effects of stations and seasons on the richness and abundance of birds of Bousaâda oasis

Diversity, Ecology and Therapeutic Properties of the Medicinal Plants in Ziban Region (Algeria)

With the aim to assess the floristic population diversity, distribution and therapeutic properties in the Ziban region (Algeria), a survey was conducted along two successive study years in the main area. The objective of this study was to contribute to the knowledge and description of this plant groups with exhaustive inventory spontaneous vegetation. In order to study the dynamics of medicinal plants, we used a quantitative method based essentially on the classic technique of linear surveys and floristic inventory using the minimum area method. The results showed that the floristic procession of medicinal plants is represented by 21 species belonging to the 13 families, with a total of 31 species for the 08 study stations, which represents 68% of the total procession. The results obtained showed that the overall recovery is higher at the Ain Ben Noui station with 69%, even if the clumps of Aristida pungens, Atractylis serratuloides and Atriplexhalimus are isolated and scattered. The lowest overall coverage at the Oumache station is less than 21%, as it is an area with sandy soils. The species that contribute most to the recovery of mobile sand accumulations is Astragalus armatus with a rate of 76.19% at the Ain Ben Noui station. Frequency results allowed us to say that Atriplex halimus and Zizyphus lotus are the ubiquitous species (100% of the surveys). On the other hand, Nitraria retusa, Teucrium polium, Shismus barbatus, Sueda mollis and Halocnemum strobilaceum are the species present in only one survey

Ecology and behavioral response of Ruddy Shelduck (Tadorna ferruginea) in the wetland complex of Oued Righ valley (Algerian Sahara)

The wetland complex of Oued Righ valley accommodates a population of Ruddy Shelduck (Tadorna ferruginea) between 2012 and 2014, the total  reached 80 individuals in the Lake Hamraia where the species wintering. The analysis of the diurnal time budget of wintering populations revealed  the role of feeding area delivery for this species and they devoted their day time to feeding (51.2%), sleeping (18.8%), followed by swimming activity  (6.3 %), and courtship activities with flying (2.03%) which often occurs after disturbances caused by human or by Marsh harrier (Circus aeruginosus). It is  interesting to study the behavior of these ducks in Saharan bioclimatic area and follow the phenology and characteristics in order to preserve the  biodiversity in this regio

ASSESSMENT RATING OF FE, CU AND ZN IN WATER AND IN TISSUES OF LUCIOBARBUS CALLENSIS (VALENCIENNES, 1842) AND CYPRINUS CARPIO CARPIO (LINNAEUS, 1785) AT K'SOB RESERVOIR (M'SILA - ALGERIA)

The aim of this study was to determine Fe, Cu and Zn in K’sob reservoir water (Msila - Algeria) and to estimate their concentration in the tissues of Cyprinus carpio carpio and Luciobarbus callensis, as an indicator of the quality of this aquatic ecosystem. The choice of these species is mainly based on endemism criteria; the Carp fish is representative species of the invasive fish communities but the Barbel is an endemic species inhabiting the course of a Wadi and the K’sob reservoir. Our study conducted from January to May 2014 with a monthly monitoring in order to analysis the concentration of the heavy metals in water and fish tissues. The reservoir water show different values of heavy metals between high concentration of Cu and a medium for Fe and Zn. While the higher concentrations of Copper were obtained from carp and important values of Iron and Zinc are shown in both species. These values appear compatible with our fish’s habitat and its diet