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Seasonal and regional variations in biochemical and physiological parameters of Artemisia campestris (L.) were investigated. The quantification of proline by the formation of a coloured complex was done by coupling proline with ninhydrin. The determination of soluble sugars and the extraction of chlorophyll from the leaves were carried out. The seasonal average leaf proline concentration of plants from the arid region was higher than that from the semi-arid region. The more the seasonal temperature increases, the greater the concentration of proline, as with the concentrations of soluble sugars in the two study regions. The distribution and accumulation of certain minerals (e.g. Sodium and Potassium) in the plant can be modified to increase resistance to heat stress. [ABSTRACT FROM AUTHOR]

Many rail species' distribution and habitat requirements are poorly known. We conducted a survey of the distribution of the Water Rail Rallus aquaticus across Algeria and investigated its possible nesting in the Sahara. Between 2002 and 2008, water rails were recorded in nine sites across Algeria and were found to breed in Lake Fetzara. In 2022, the species was recorded at yet another site, El Ménia, where two nests were found to contain clutches of three and seven eggs, respectively. This is the first unequivocal record of the Water Rail breeding in the Sahara. [ABSTRACT FROM AUTHOR]

The Algerian Saharan rangelands are an arid ecosystem characterized by limited soil, water, and vegetation resources, which make it very susceptible to degradation. This research focuses on the diachronic assessment and multi-temporal mapping of the degradation of steppe vegetation in the south of Biskra during the period 1987–2019, using remote sensing data (MSAVI index), for extracting spatiotemporal data to monitor the rangeland vegetation dynamics. We examined demographic evolution, number of livestock, and land use from quantitative data. The results show that during this period, the landscape of the region changed considerably. The area of rangelands decreased from 19,939 ha (1987) to 3605 ha (2019), where 58% of the pre-existing vegetation was transformed into bare soil. This study confirmed that the rangeland vegetation health is closely related to climate, and its degradation is mainly due to the recurrence, duration, severity, and magnitude of drought events. Manmade activities were also a determinant factor of long-term degradation of the rangeland, such as the expansion of new land development areas that increased from 3754 ha (1987) to 24,410 ha (2019). This trend was found throughout the region, including predominantly pastoral regions such as Oumache and El Haouch, leading to overgrazing with a loss of about 2% of vegetation cover. All these factors have led to a severe and continuous degradation of pastoral resources in a vulnerable environment. The preservation of these limited resources requires appropriate management of the ecosystem and a rational exploitation of its vegetation, soil, and water resources. [ABSTRACT FROM AUTHOR]

Considering three sites under different climate conditions (arid, semi-arid, and subhumid), this study aims to use the vadose-zone water stable isotope profiles to estimate the groundwater recharge rate. High-resolution vertical subsurface soil sampling along the vadose zone of the investigated sites was conducted. The collected samples were analysed to determine their stable isotope ratios (δ2H and δ18O) that were used along with the piston displacement method to estimate recharge. Annual recharge rates of 0.2% (± 0.1%), 2.5%, and 18% of the total annual precipitation were obtained for the arid, semi-arid, and subhumid sites, respectively. Recharge rates at the semi-arid and subhumid sites are comparable to those previously estimated using water balance-based methods. The recharge rate at the arid site is lower than that previously estimated for that site using the water budget-based method, revealing difficulties in applying the piston displacement method under an arid regime. [ABSTRACT FROM AUTHOR]

Serum progesterone, estradiol 17-β and energetic metabolites profiles were investigated during the spring breeding season in non-pregnant and pregnant "Ouled Djellal" ewes bearing singleton or twin fetuses in arid and semi-arid climates of Algeria. Twenty and thirty ewes aged 1 to 4 years from semi-arid and arid zones, respectively, were used. In semi-arid zone, 15 ewes were pregnant (eight carrying one fetus and seven carrying twins). In arid zone, from 24 pregnant ewes, 14 carried singleton and 10 carried twins. Blood sampling were collected before mating, in the first and the last month of pregnancy and after lambing. Significant effect (p < 0.05) of litter size was found during early gestation on progesteronemia in arid region and on estradiolemia (p < 0.05) in both regions. During late pregnancy significant effect of fetal number was observed in semi-arid (p < 0.05) and arid (p < 0.001) area for progesterone and only in arid zone (p < 0.05) for estradiol. In the present study, no significant effect of litter size was found on serum glucose, cholesterol and triglycerides in both regions. Reproductive hormones profiles and energetic metabolism in pregnant ewes raised in arid zone are more altered than those in semi-arid zone. [ABSTRACT FROM AUTHOR]

A livestock survey conducted during 2013/2015 as part of a CRSTRA project in 4 villages situated at North east Biskra and south Batna in Algeria. These regions are located at elevation ranging around 250-831m asl, experiencing arid and semi-arid Mediterranean climate. Respondents of 86 families demonstrated that livestock is an integral part of the region's mixed farming systems. Low livestock numbers per most households at present reflect the selfconsumption breeding mode adapted in these regions. Currently, farmers focus on four main livestock types; goat, sheep, chicken and bee keeping in two regions, it is the case of Beni Souik and Branis, while Maafa includes beyond these types, turkey and pigeon whereas Ain Zaatout includes duck and swine beside the previous livestock types. In the same context; goat ranked first in the four regions, goat and sheep secondly then goat and poultry with goat combined to sheep and poultry in third place. Thus; most families use a combination of grazing, agriculture sub-products and industrial products for the nutrition of their livestock. Families keep livestock as source of milk, butter, wool or hair, leather and other products that are strongly used as nutritional, weaving supply or stocking covering resources for the family members or friends and in some cases for sell to seekers of animal products of indigenous territory origins. Most families use these products for family and friend consumption while a minority sell some of them on local markets. [ABSTRACT FROM AUTHOR]

Abstract: Through monthly samplings of grasshoppers taken from five sites in oases and two in steppes in the area of Biskra, 45 species could be recorded. Four assemblages of species can be defined, two in the oasian zones, one in the stony steppe and a last one in the sandy steppe. The two oasian assemblages are interpreted in the light of a gradient of salinity and humidity determined by the vegetation. In each type of steppe, there is a spring sub-assemblage and a summer-autumnal one, but such a distinction is not possible in the anthropised sites. The steppe stations are moreover characterized by a larger diversity determined by the Shannon index and a weaker density than in the oases, in spite of a comparable richness. The comparative analysis of species phenology between the different assemblages allows discussing their adaptation toward seasonal variations of dryness in these arid environments. [Copyright &y& Elsevier]