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This study aims to assess the amount of organic carbon stored in soils, as it is an intention of knowing the sustainable soil management, by using two common methods for determining soil organic matter (SOM), namely oxidation with acidified wet dichromate (Walkley–Black method-WB) and loss on ignition (LOI). The study was carried with soil samples collected from a depth of 0 to 30 cm in the Saharan arid region of Ghardaïa (Algeria), with different land uses: agricultural, forest and pastoral. The results obtained from the LOI and WB methods were subjected to statistical analysis, and the relations between both methods were tested to investigate their relationship. The mean percentage of SOM values were 1.86, 2.42, 1.54 by using LOI, but, lower values of 0.34, 0.33, 0.36 were determined by using WB method, for agricultural, forest and pastoral soils respectively. A weak linear relationship between the two analytical procedures was obtained (R2 of 0.19 and 0.13 for agricultural and forest soils), while a medium relationship (R2 = 0.65) was found for pastoral soils when using linear adjustment. However, the opposite behaviour was found when we use the logarithmic adjustment. The study outcomes indicated discrepancies in the measurements of SOM values between the two methods, been higher those estimated with LOI. Finally, in order to identify the best methodology to measure soil organic matter in arid soils, more research is required in these extreme arid regions as they are a gap in world soil organic matter maps. [ABSTRACT FROM AUTHOR]

Study region: The Miocene Fluvial Moghra Aquifer in the North Western Desert of Egypt Study focus: The study integrates stable isotope analyses with aeromagnetic and hydrogeological datasets to accomplish the following: (1) define the primary source(s) of recharge to the Moghra aquifer, (2) assess aquifer connectivity with the Nile River aquifer, and (3) investigate the vertical connectivity of the Moghra aquifer with the underlying Nubian Aquifer System (NAS) through subvertical faults. New hydrological insights for the region: The findings reveal (1) significant heterogeneity in groundwater isotopic compositions (Group A: δ18O: 1.1–13.8 ‰; δD: 4.6–73.5 ‰, B: δ18O:−0.99 to 0.85; δD: −7.58 to 4.38 ‰; and C: δ18O:−1.1 to −3.4; δD: − 6.3 to −18.2 ‰) indicative of variability in recharge sources. (2) Groundwater compositions west (up to 30 km) of the Nile River (Group A) resemble enriched modern Nile waters following the Aswan High Dam (AHD) construction that give way further west to relatively depleted groundwater (Group B) resembling historical pre-AHD Nile water compositions. (3) Further west from Group B depleted Group C samples occur along intersections of multiple fault systems (NW and NE-oriented faults) interpreted as mixtures of rising highly-depleted paleo Nubian Aquifer System (NAS) waters and pre-AHD Nile waters. (4) The advocated structural control is reported in similar settings in Egypt, suggesting that intersections of multiple fault systems provide regional connections between deep and shallow aquifers in northeast Africa, recharge overlying shallow aquifers, and should be considered in groundwater management scenarios.

This study investigates the influences of air temperature (T), relative humidity (RH), wind speed (WS), clearance index (KT), particulate matter (PM) concentrations (PM10 and PM2.5), and aerosol optical depth (AOD) on ultraviolet (UV) radiation during clear skies in Riyadh, central Saudi Arabia. The observational dataset utilized in this study comprises global solar radiation (G), UVA radiation, AOD measurements, and PM concentrations. The data were collected from 2014 to 2015 at the King Abdulaziz City for Science and Technology (KACST) campus in Riyadh. Regression analyses were conducted to investigate the relationships between UV radiation and the considered variables. The methodology is based on the least square method and associated statistical tests. The findings of this study provide valuable insights into the impacts of meteorological variables and aerosols on UV radiation, contributing to the understanding of environmental and industrial applications in the Arabian Peninsula. The analyses showed that the strengths and magnitudes differed from one variable to another. No significant correlations between UVA radiation (315–400 nm) and hourly and daily values of PM2.5 were found. Moreover, no significant correlations were seen between daily values of the UVA radiation and RH and between the UVB (280–315 nm) and PM10. The rest of the correlations (between UV radiation and the PM10 and meteorological variables) were found to be significant. While WS, the ratio of the PM concentrations (PM2.5/PM10), KT, and T exhibited positive correlations with UV radiation, the rest of the variables had anti-correlations with UV radiation. The influences of T, WS, and RH on ambient PM concentrations during the considered period were taken into account, and it was found that the PM concentrations correlate, with different magnitudes and strengths, positively with T and negatively with RH and WS. [ABSTRACT FROM AUTHOR]

Atriplex nitens, which can easily grow in arid and saline conditions and produce high amounts of roughage and seed material, has been seen as an important advantage in both closing the forage deficit and bringing marginal areas into production. However, agronomic studies on the plant are limited, and there is no study revealing the effect of inter-row spacing on seed yield. For this purpose, for 2 years (2021-2022), a study was planned to determine the effect of inter-row spacings (22.5, 45.0 and 67.5 cm) on seed yield components in Atriplex nitens grown under unsoiled and rainfall conditions in Iğdır with arid climate. The study was established according to the randomized blocks experimental design with 3 replications. Some parameters showed significant differences according to inter-row spacing. The highest plant height (3.19 m), stem thickness (17.0 mm) and maturation time (192.3 days) were measured in the plots grown with 67.5 cm row spacing, and the highest seed yield (1315 kg/da), the highest stem yield (3970 kg/da) and the highest biological yield (5285 kg/da) in the plots grown with 22.5 cm row spacing. However, harvest index (28.94 - 29.36%) and bracteole thousand grain weight (10.71 - 11.49 g) were determined in the plots grown with 45.0 and 67.5 cm row spacings. When evaluated in terms of years, plant height was high in 2022, while maturation time, pericarp thousand grain weight and harvest index were found to be higher in 2021 when the amount of rainfall was high in the months corresponding to the generative phase of the plants. However, the other parameters examined were not affected by rainfall amounts that vary according to years. [ABSTRACT FROM AUTHOR]

The article presents results of studying the distribution of alien species on the territory of six districts of Zhetysu oblast, located in the Southeastern Kazakhstan. The data obtained will make it possible to summarize up-to-date information about the state of ecosystems with invasive plant species, predict their further spread, and develop a strategy to control them. The objects of research were natural ecosystems of Zhetysu oblast, confined to the Balkhash-Alakol and Zhongar-Alatau floristic districts. To identify alien species, monitoring sites were laid with the calculation of native species, introduced species, the species prone to naturalization, and those with self-seeding. The aggressiveness of naturalized species was assessed according to a modernized scale developed at the Institute of Botany and Phytointroduction, Committee of Forestry and Wildlife, Ministry of Ecology, Geology, and Natural Resources of the Republic of Kazakhstan. The territory under study includes two State National Nature Parks and a State Nature Reserve. Eighty-one alien species of woody plants have been identified within settlements and adjacent territories. Some of them are included in the cultivated flora, which do not show a tendency to naturalization in the region. Seventeen species of alien woody plants have been identified in natural ecosystems, which have the potential for naturalization with a high propensity for seed and vegetative reproduction. The percentage of sites with the presence of invasive species varies from 61 to 91%. The highest aggressiveness score (6–8) was assigned to six species: Acer negundo L., Ulmus pumila L., Quercus robur L., Prunus × domestica, Fraxinus pennsylvanica, Ulmus laevis Pall.. Despite the fact that, in the Alakol and Sarkand districts, most of the territory falls within the dry-steppe and semidesert zones, only 8.6% of sites without types of invasive fraction were noted, owing to widespread dispersion of particularly aggressive "edificators": A. negundo, U. pumila, etc. All identified species mesophytic by their nature in the secondary range show themselves highly adaptive, plastic, and competitive in xerophytic conditions. [ABSTRACT FROM AUTHOR]

Background. Winter wheat is a key crop in most farms of the Volgograd region and the south of Russia. However, despite the high annual gross harvest of wheat grain in the region (4 million tons or more), its stabilization and increase in production are complicated by global and local climate changes, depletion of soil fertility, environmental pollution, narrowing of biodiversity of crops used in crop rotation, and other negative factors. The impact of external environmental factors on grain production is extremely difficult and requires a systematic approach in the study. Among the main trends in climate change, scientists of the Federal Research Center of Agroecology of the Russian Academy of Sciences note a steady increase in average air temperatures of the autumn-winter period, an increase in intra-seasonal variability. Purpose. Improving the technology of winter wheat cultivation, studying the effect of mineral fertilizers and new biological products on the yield and quality characteristics of grain in the conditions of light chestnut soils of the Volgograd region Materials and methods. The study of the effect of trace elements on the yield of winter wheat of the Kamyshanka 4 variety, as well as the analysis of qualitative indicators in the arid conditions of the Volgograd region based on the methodology of B. A. Dospekhov and gossorto-testing. Results. According to the conducted studies, the greatest effect on the yield and quality of winter wheat was formed on the treatment with preparations of the Biostim series that affect the balance of nutrients during the growing season, protection from the effects of abiotic processes, restoration of crop productivity after stress. Conclusion. When choosing plant nutrition with trace elements, it is necessary to proceed from soil and climatic conditions. As a result, in the arid conditions of the Volgograd region, results were obtained showing the important role of amino acids and trace elements in maintaining the balance of nutrients throughout the vegetation of plants.

A 3-year rainfed field experiment was carried out to determine the effects of combined tied ridges and cattle manure application rates on maize productivity. The experiment was laid as a 2 × 4 factorial in a completely randomized block design (CRBD) with three replicates. Treatment combinations were tied ridges + 7.5 t ha−1 low cattle manure (TLM), tied ridges + 15 t ha−1 standard cattle manure (TSM), and tied ridges + 22.5 t ha−1 high cattle manure (THM) application rates. No-tied ridges + low, medium, and high quantities of cattle manure were used as positive controls. Early maturing maize variety (SC537) was then planted at 52,000 plants ha−1 in each plot. Soil water storage, soil bulk density, rainfall, dry matter accumulation (DMA), and grain yield were measured. Rainfall use efficiency (RUE) was then calculated. Analysis of variance was carried out to determine the effects of tied ridging and cattle manure on soil moisture content, RUE, and grain yield. The addition of cattle manure in tied ridges increased the soil moisture content, RUE, DMA, and grain yield. The measured parameters were significantly (p < 0.05) increasing with an increase in the quantity of cattle manure applied. The THM had 40% higher soil moisture content, 20% more RUE, and > 50% DMA compared to TLM. Grain yields significantly (p < 0.05) increased with an increase in application rates of cattle manure with the highest (3.2 t ha−1) recorded in the 2022 season under the THM treatment. The THM had significantly (p < 0.05) higher grain yield compared to no-tied ridges combined with corresponding cattle manure application rates. Farmers can practice tied ridges and 22.5 t ha−1 cattle manure to improve RUE and maize grain yields in the semi-arid areas of Zimbabwe.

This study investigates the influences of air temperature (T), relative humidity (RH), wind speed (WS), clearance index (KT), particulate matter (PM) concentrations (PM10 and PM2.5), and aerosol optical depth (AOD) on ultraviolet (UV) radiation during clear skies in Riyadh, central Saudi Arabia. The observational dataset utilized in this study comprises global solar radiation (G), UVA radiation, AOD measurements, and PM concentrations. The data were collected from 2014 to 2015 at the King Abdulaziz City for Science and Technology (KACST) campus in Riyadh. Regression analyses were conducted to investigate the relationships between UV radiation and the considered variables. The methodology is based on the least square method and associated statistical tests. The findings of this study provide valuable insights into the impacts of meteorological variables and aerosols on UV radiation, contributing to the understanding of environmental and industrial applications in the Arabian Peninsula. The analyses showed that the strengths and magnitudes differed from one variable to another. No significant correlations between UVA radiation (315–400 nm) and hourly and daily values of PM2.5 were found. Moreover, no significant correlations were seen between daily values of the UVA radiation and RH and between the UVB (280–315 nm) and PM10. The rest of the correlations (between UV radiation and the PM10 and meteorological variables) were found to be significant. While WS, the ratio of the PM concentrations (PM2.5/PM10), KT, and T exhibited positive correlations with UV radiation, the rest of the variables had anti-correlations with UV radiation. The influences of T, WS, and RH on ambient PM concentrations during the considered period were taken into account, and it was found that the PM concentrations correlate, with different magnitudes and strengths, positively with T and negatively with RH and WS.

This study was carried out in Iğdır ecological conditions for two years (2019-2020) in order to determine the effects of different sowing times on the seed yield of mountain spinach. In the study, the effects of different sowing times on the plant height, number of branches, stem diameters, maturation time, biological yield, stem yield, harvest index, seed yield and thousand grain weight of mountain spinach were determined. The research was carried out in dry conditions with three replications according to the randomized blocks experimental design. The effect of sowing times (except thousand grain weight) on the parameters examined in the study was found to be statistically significant. Delaying the sowing time caused significant decreases in the investigated parameters. When evaluated in terms of years, plant height, number of branches, maturation time and thousand grain weight were found to be statistically significant, and these values (except thousand grain weight) in the rainy 2020 year were higher than in 2019. According to the two-year average results, the highest stem yield (3541.5 kg/da), seed yield (1586.6 kg/da) and biological yield (5128.1 kg/da) were obtained from sowing in mid- March, which is the first sowing time. [ABSTRACT FROM AUTHOR]

The effect of mineral fertilizers and a growth biological stimulant on the development and fruiting of the species Robinia pseudoacacia (Robinia pseudoacacia L.) is analyzed. The introduction of robinia into plantations of various types has been performed from 1904 to the present time. It has been revealed that this North American species successfully grows and develops under arid conditions of Volgograd oblast, is adapted to local soil and climatic conditions, and is stable. Observations were performed in the Kirov Forestry of Volgograd oblast and in the production nursery of the Federal State Unitary Enterprise Volgogradskoe of the Federal Scientific Center for Agroecology, Complex Melioration, and Protective Afforestation of the Russian Academy of Sciences. The studies enabled us to determine the effect of treatment with preparations Biostim and Agrovit on reproductive ability, biometric parameters of young and mature robinia plants, and germination of seeds. Seeds of Robinia pseudoacacia are needed for 2633 ha in Volgograd oblast and for 192 ha in the semi-desert zone. The need for seeds for the entire area of protective forest plantations in Astrakhan oblast and the Republic of Kalmykia is 333 and 2594 kg, respectively. The testing of the Biostim Start growth biostimulant has shown that it optimal treatment rate for robinia seeds is 15 mL/L. A higher rate causes a decrease in vitality and mold development on seeds. The use of the Agrovit preparation causes an increase in the growth and diameter of trees in 10-year-old plantations. Application of the preparation in combination with mineral fertilizers causes a growth to 40 cm of young frost-tolerant plants and to 60 cm of tall trees. The crown diameter of frost-tolerant plants increases to 6.2 cm. The research results show the possibility of sowing robinia seeds at the rate of 2 kg/ha and at a distance of 2.5 m between rows with the use of Agrovit fertilizer. [ABSTRACT FROM AUTHOR]

Mass gathering events commonly encounter environmental challenges that necessitate assurance of water quality and food security. The current outbreak of the coronavirus disease 2019 (COVID-19) call for maintaining safe drinking water supply and providing assessment tools of drinking water quality to avoid contamination in water sources or distribution networks. Arid environmental conditions also add more stress on supplied water to mass gathering events. Herein, we assess the quality of the water supply (desalinated 95% and groundwater 5%) in Makkah city, Saudi Arabia during a mass gathering event in 2019 (9.6 million people) for religious purposes. Fifty five samples were randomly collected from nine different districts of Makkah city, analyzed for TDS, turbidity, pH, EC, free Cl2, Al, Cd, Pb, Cr, F, major ions, coliform and E.coli bacteria and were finally used to estimate the water quality index (WQI). Major ions, trace elements and heavy metals analyses show values below permissible limits in most of the samples, while a few samples show slightly higher values. No bacterial count found in any sample. WQI values of all fifty-five samples were below 50 and were identified as “excellent water”. The WQI variations could be attributed to the distribution network conditions rather than a direct impact of adding groundwater with uncontrolled chemical composition. The use of WQI to report the quality of water during mass gathering events to governmental authorities has been proved to be beneficial and should be applied for further mass gathering events worldwide.

The results are presented for a study of the biotechnological properties of the introduced Moldova variety, which grows in different soil and climatic conditions of the arid territories of Dagestan. Features of the synthesis of the components of carbohydrate, acid, nitrogen, phenolic, amino acid and vitamin complexes have been determined with respect to the cultivation location. It is noted that the Moldova variety can synthesize a large amount of valuable nutrients at a low moisture supply and high indicators of the sum of active temperatures. This variety has demonstrated ecological plasticity and technological versatility, and it has been experimentally proven that high-quality wine materials can be obtained from it for the production of sparkling and original special wines. Thus, the expansion of areas of grape planting in arid conditions is expedient. [ABSTRACT FROM AUTHOR]

The accumulation of moisture from autumn and winter precipitation in poorly draining soil for plants in arid conditions during the initial stage of the vegetation period in the northern region of Kazakhstan was a severe production problem. Research methods included theoretical and experimental studies. In theoretical studies, the area of the treated surface by a chain harrow is determined. Then, the design of an improved harrow is proposed, including how the tooth chain tillage tools are positioned. Either as a “single action disc harrow” type with mounting four teeth on each chain link, or as a serial harrow with the tooth chain tillage tools located in a “diamond-shaped” double-action scheme with two teeth on each chain link. Experimental studies show that an improved harrow steadily performs the early spring harrowing process with a quality that meets normative requirements. In doing, so the working capacity is 4–5% higher than a serial harrow with a 4–5% lower fuel consumption. Furthermore, it is revealed that the early spring soil harrowing performed by tooth chain harrows allows the loss of productive moisture in the spring pre-sowing period by 1.8–1.9 times to be reduced compared to the untreated background. [ABSTRACT FROM AUTHOR]

The decline of soil organic carbon (SOC) has aggravated salinity-related problems in semi-arid irrigation areas of the Awash river basin, Ethiopia. This study aimed at evaluating the performance of potential remediation crops on saline soil and their effectiveness for remediating soil salinity and improving pH, SOC, bulk density (BD) and hydraulic conductivity (HyCo). Rhodes grass (RHG), alfalfa (ALF), sudangrass (SUG) and blue panicgrass (Retz) (BPG) were grown in saline (3-13.9 dS/m) field plots. The crop biomass was incorporated into the soil immediately before flowering. The results show that at high soil salinity levels, BPG and SUG grew well, with the harvesting frequency of BPG being much higher than for SUG. Conversely, the growth of ALF and RHG was strongly inhibited by high soil salinity. Significant (P < 0.05) reduction of soil salinity levels (-3.2 dS/m) and related ionic concentrations, an increase of SOC (0.8% to 1.6%) and improvement of BD and HyCo were observed in BPG plots. The fast-growing nature of BPG in the hot climate of the experimental area resulted in harvests every three weeks and promoted the incorporation of high amounts of biomass to the soil and efficient soil salinity remediation. At moderately saline conditions, ALF also showed a great potential for salinity reclamation (-1.8 dS/m) and SOC accumulation. The cultivation of fast-growing annual crops proved an efficient and low-cost strategy for soil salinity mitigation and the reclamation of salinity-associated soil degradation in irrigation agriculture in Ethiopia.

Hyper-arid regions, such as the Sultanate of Oman, require precise information regarding actual water application to develop efficient irrigation management. Remote sensing techniques with imagery models can be used as practical tools in irrigation practices by estimating the actual evapotranspiration (ETa) at local and regional scales. In this study, spatial and temporal changes in the ETa were evaluated by investigating the performance of three different models, including two surface energy balance models: surface energy balance algorithm for land (SEBAL) and mapping evapotranspiration at high-resolution internalized calibration (METRIC), as well as an agro-hydrological model: soil, water, atmosphere, and plant (SWAP), for the hyper-arid conditions of Oman. This study is unique in its field application, as very few studies have conducted ETa estimations using satellite imagery in the hot and hyper-arid regions of Oman. In situ meteorological data were integrated with Landsat-8 operational land multispectral imagery and thermal infrared sensor satellite images. Further, a sensitivity analysis comparing the three models' estimated ETa with in situ sap flow field measurements (SFM) and the Penman-Monteith (PM) model. The results showed that the SEBAL model overestimated the sensible heat flux compared with the METRIC model. Although the PM model showed a higher correlation (R2 = 0.87) with the SFM, the METRIC model, among all the investigated models, showed the highest correlation of R2 = 0.83. Further, the SEBAL and METRIC models overestimated the ETa, especially in the summer. Conversely, SWAP underestimated the ETa, as compared with the SFM. These results show that the METRIC model estimates the ETa with high spatial and temporal accuracy. Meanwhile, the SWAP model was the least suitable model for estimating the ETa under the hyper-arid condition of Oman. These findings will act as a reference for accurate water requirements, thereby linking water resource management and future irrigation scheduling in local hot and hyper-arid conditions. [ABSTRACT FROM AUTHOR]

Excess heat has a negative effect on the growth and development of fruit plants, their productivity, so the success of introduction under conditions with a hot climate is determined by the plants resistance to overheating. The article presents for the first time the results of the heat resistance study of 10 introduced apple-tree varieties in seasonal dynamics due to their water content, transpiration rate and seasonal development. It was found that the heat resistance varied in different varieties and changed during the growth, decreasing in August-September in all varieties. Maximum values of water content in the leaves was observed in May and minimum in August-September. The maximum transpiration rate was from June to August, depending on variety. High heat resistance, water content and low transpiration rate were observed in all varieties at the end of May, against the background of a drop in the growth rate of shoots. At the completion time of shoot growth and the beginning of fruit ripening, the water content decreased in all varieties, transpiration rate varied in different directions, and heat resistance decreased in all varieties except the most stable ones (Stolovka, Renet Burkhardta). After fruit ripening and shoots lignification, water content, transpiration rate and heat resistance decreased in all varieties. The most productive varieties were characterized by high heat resistance. The work was carried out on the topic of the Grant Project "Introduction of prospective apple-tree varieties for introduction into culture in the arid regions of West Kazakhstan". [ABSTRACT FROM AUTHOR]

The content and dynamics of chlorophylls a and b of the photosynthetic organ (leaf) of representatives of the genus C anna L. were studied at different phases of plant growth and development: at the beginning of the growing season, in the generative phase, at the end of the growing season under conditions of Kryvyi Rih. A high content of chlorophylls in the leaves of most of the studied canna varieties was noted, compared with the species (with the exception of C. indica). A common trend for canna plants was an increase in the total number of chlorophylls in generative phase. Varieties of canna Capter, Vesolyye notki, Richard Wallis, which have litle leaf parameters, were characterized by a low total content of photopigments during the growing season and chlorophyll b in the generative phase, which indicates a significant sensitivity of plants to arid conditions in the region. Plants of the Fauervogel, Rosenkranzen and Krymskiye Zori varieties (with large leaf blades) were characterized by a high concentration of green pigments during the growing season, and chlorophyll b in the generative phase, this feature in the functioning of the photosynthetic apparatus is consistent with a high assessment of the level of adaptation of these plants in drought conditions. Therefore, indicators of the state of the assimilation apparatus of plants of the genus Canna L. can be used to determine their level of fitness for moisture deficiency during introduction studies. [ABSTRACT FROM AUTHOR]

Alluvial fans are usually constructed through episodic flood events. Despite the significance of these ephemeral floods on the morphodynamics of alluvial fans, depositional responses to the variations in flood conditions are still poorly documented. This greatly limits the ability to interpret ancient sedimentary successions of fans and the associated flood hydrodynamics. The Quaternary Poplar Fan from endorheic Heshituoluogai Basin provides an optimal case for addressing this issue. Based on the variations in facies associations and flood conditions, three depositional stages – namely; lobe building stage, channel building stage and the abandonment stage – are identified. During the lobe building stage the Poplar Fan is predominately constructed through incised channel flood, sheetflood and unconfined streamflood, with coeval development of distal surficial ephemeral ponds. The channel building stage is characterized by the development of gravelly braided rivers. However, only scour pool fill deposits are preferentially preserved in the Poplar Fan. During the abandonment stage, erosional lags and aeolian sands randomly occur throughout the fan, while gully deposits can only be found in the distal fan. The distinctive facies architecture of the Poplar Fan is likely to be the result of periodicity of climate fluctuations between wetter and drier conditions during the Late Pleistocene to Holocene. The ephemeral floods formed under wetter conditions usually show high discharge and sediment concentrations which facilitate the lobe building processes. During the drier periods, only gravelly braided rivers can be developed through ephemeral floods as the intensity and frequency in precipitation, discharge and sediment concentrations of the flood flows significantly decrease. The abandonment stage of the fan may occur between recurring flood episodes or during the driest periods. Furthermore, the long‐term (105 to 106 year) geomorphic evolution of the Poplar Fan shows the influence of tectonic activities. The ongoing thrust uplift tectonic activities have caused destruction of the fan but can also facilitate the fan‐head trench/incision of the fan, which in turn facilitate the progradation of the fan. This study proposes a new depositional model for alluvial fans constructed through episodic flood events, which shows the character of both sheet‐flood dominated and stream‐flow dominated end members of alluvial fans. These findings supplement the understanding of the variability of the alluvial fans and provide means to characterize rock record of alluvial fans and their associated flood and climate conditions. [ABSTRACT FROM AUTHOR]

This research aimed to determine the effect of different boron levels to grain yield and some phenological characteristics of Evirgen red lentil variety (Lens culinaris Medic.). Study was conducted during the winter months of the years 2013-2014 and 2014-2015 growing years in the Boron deficit areas of Sanliurfa, Turkey. The experimental design was randomized complete block design with four replicates. Evirgen lentil variety and Borax were used as plant material and Boron source, respectively. Boron levels were control (0 kg B ha-1), 0.75 kg B ha-1, 1.5 kg B ha-1, 2.25 kg B ha-1, 3 kg B ha-1 and 3.75 kg B ha-1. Boron levels were significant at protein ratio and grain yield. Boron content of grain, leaf and soil increased with increasing boron levels. Although the highest grain yield was obtained from 1.5 kg B ha-1 in both years, according to regression analysis optimum boron level was found at 1.7 B ha-1. But the economical boron level was determined as 1.5 kg B ha-1. Due to avoid from boron toxicity, boron content of soil should be determined before every application of boron to soil and advised dosage should be used in the boron deficit areas. [ABSTRACT FROM AUTHOR]

Studying the peculiarities of the water status of fruit plants allows revealing the mechanism's of adaptation of introduced species to the arid conditions, their relationship with the development phases and productivity of varieties. The paper presents for the first time the results of a study of leaf water content and intensity of transpiration of 10 introduced apple varieties in their daily and seasonal dynamics. Under the conditions of drop irrigation, a sharp increase in the intensity of transpiration in the middle of the day was revealed for all varieties, as well as fluctuations in the water content of leaves and the intensity of transpiration during the vegetative season associated both with extreme values of air temperature and humidity, and with the phases of growth and development of varieties. In seasonal dynamics, from one to three peaks of water content and transpiration intensity have been noted. The maximum water content of the leaves was observed in May, the maximum transpiration intensity was observed at different times from June to August and for the most productive varieties - on 20th of June. By the amount of transpirating moisture consumption, apple varieties are classified as medium- and low-transpirative. [ABSTRACT FROM AUTHOR]

The bioactive compounds, total antioxidant activity and minerals in white, pink and red flesh guava (Psidium guajava L.) varieties were assessed and quantified at three different stages of maturity in arid conditions. Changes in pectin content followed similar trend as fruit firmness and it gradually decreased till ripe stage. Total soluble solids and total sugars increased till full ripe stage but reverse was case for acidity. Ascorbic acid in white flesh guava varieties increased till colour turning stage and then after it decreased, while in coloured varieties it showed decreasing trend till ripe stage. White flesh varieties contains negligible quantity of anthocyanin, lycopene and total carotenoid while pink flesh (Lalit) had highest concentration of these compound followed by red flesh (Red flesh). Total phenols and total antioxidant activities of guava fruits were comparatively low during green mature stage and it increased progressively in later stages. Flesh colour did not show any definite pattern on phenolic content and total antioxidant activities. Phenols was recorded highest in Allahabad Safeda, while total antioxidant activities in Lalit. Stage of maturation showed variable changes in mineral contents in guava varieties. It can be inferred from the present study that the remarkable metabolic changes occur between mature green to colour turning stage.

Our study attempted to elucidate the significance of floral and pollen traits of the highly nutritious tropical trees Moringa oleifera and Moringa peregrina for their reproductive success under arid conditions. We found that the pollen grains of both species were immersed in a pollenkitt that constituted ~60% of the pollen. Successful pollination was achieved by large bees inserting the pollen into a narrow stylar tube. We found that, upon removal of the pollenkitt, approximately 65% fewer pollen grains penetrated the stylar tube for both species. The pollenkitt protected against heat and desiccation, while removing the pollenkitt resulted in significantly reduced levels of the viability of pollen grains, especially in M. oleifera, and significantly reduced levels of germinability in both species. The stylar tube provided high protection for pollen grains against heat and desiccation even when the pollenkitt was removed. Chemical analysis of pollenkitts of the two species revealed a waxy blend of 21 hydrocarbon compounds, in which n-alkanes constituted >90% of the compounds and their identity corresponded to known plant and animal hydrocarbons, associated with protection against heat and water stress. We concluded that, under arid conditions, the reproductive success of both Moringa species is potentially enhanced by their unique floral and pollen traits. This supports the prospect of cultivating M. oleifera and Moringa peregrina as food crops in arid regions across the globe.

For the first time the article presents perennial statistically processed results of pheno-observations for 11 apple varieties introduced into the Mangyshlaksky Experimental Botanical Garden, located in the west of Kazakhstan, whose natural conditions are characterized by sharp fluctuations of air and soil temperature in both summer and winter periods, aridity and high content of readily soluble salts in soil with underlying slab of Sarmatian limestone. They determined the average phenodates of the main phenophases and the average duration of growth and development periods among apple varieties, and their variability was revealed. It was noted that generative organs are characterized by significantly lower variability than vegetative ones. In local conditions, there was a significant decrease in the fruiting period, the decrease of yield and the average weight of fruits. The most resistant and productive varieties were selected. The work was conducted on the grant project topic "Introduction of apple tree promising varieties into the culture in arid regions of Western Kazakhstan". [ABSTRACT FROM AUTHOR]

This research aimed to determine the effects of different zinc (Zn) levels on the grain yield and some phenological characteristics of the Fırat-87 red lentil variety (Lens culinaris Medic.). The study was conducted during the winter months of 2013-2014 and 2014-2015 in Zn-deficit areas of Şanlıurfa, Turkey. The experimental design was a randomized complete block design with 4 replicates. The Fırat-87 lentil variety and Zn sulfate (ZnSO4.7H2O) were used as the plant material and Zn source, respectively. The Zn levels used were the control (0 kg ha-1 Zn), 5 kg ha-1 Zn, 10 kg ha-1 Zn, 15 kg ha-1 Zn, 20 kg ha-1 Zn, and 25 kg ha-1 Zn. The Zn levels were significant (P ≤ 0.01) for the harvest index, 1000-kernel weight, protein rate, and grain yield. All of the tested characteristics were positively affected by increasing applications of Zn. The grain, leaf, and soil Zn contents were higher with increasing levels of Zn. Although the highest grain yield was 15 kg ha-1 Zn in both years, according to the regression analysis, the optimum Zn level was 17 kg ha-1 Zn. However, the economic Zn level was determined as 15 kg ha-1 Zn. [ABSTRACT FROM AUTHOR]

The decline of soil organic carbon (SOC) has aggravated salinity-related problems in semi-arid irrigation areas of the Awash river basin, Ethiopia. This study aimed at evaluating the performance of potential remediation crops on saline soil and their effectiveness for remediating soil salinity and improving pH, SOC, bulk density (BD) and hydraulic conductivity (HyCo). Rhodes grass (RHG), alfalfa (ALF), sudangrass (SUG) and blue panicgrass (Retz) (BPG) were grown in saline (3-13.9 dS/m) field plots. The crop biomass was incorporated into the soil immediately before flowering. The results show that at high soil salinity levels, BPG and SUG grew well, with the harvesting frequency of BPG being much higher than for SUG. Conversely, the growth of ALF and RHG was strongly inhibited by high soil salinity. Significant (P < 0.05) reduction of soil salinity levels (-3.2 dS/m) and related ionic concentrations, an increase of SOC (0.8% to 1.6%) and improvement of BD and HyCo were observed in BPG plots. The fast-growing nature of BPG in the hot climate of the experimental area resulted in harvests every three weeks and promoted the incorporation of high amounts of biomass to the soil and efficient soil salinity remediation. At moderately saline conditions, ALF also showed a great potential for salinity reclamation (-1.8 dS/m) and SOC accumulation. The cultivation of fast-growing annual crops proved an efficient and low-cost strategy for soil salinity mitigation and the reclamation of salinity-associated soil degradation in irrigation agriculture in Ethiopia. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Using different methods of Fe fertilization including nano, chelated and siderophore. • Nano and siderophore significantly affecting cumin yield and seed fortification. • Fe concentration of 1 g/l was the most efficient one for the fertilization types. • The findings are of great nutritional, environmental and economical significance. Abstract Cumin (Cuminum cyminum L.) from the Apiaceae family and as an important medicinal plant is greatly used for food production and medicinal purposes. The plant requires macro- and micro-nutrients including iron (Fe), which is not available under calcareous conditions. Accordingly, it was hypothesized the proper source (including the new methods of fertilization) and concentration of Fe can provide cumin with its required amounts of Fe under calcareous soils. The objectives were to determine: 1) the most efficient source of Fe fertilization (by spraying) on cumin yield and Fe uptake, and 2) the most optimum Fe concentration for cumin growth, yield production and seed fortification. A field experiment, as a completely randomized block design, with three replicates was conducted in the city of Aligudarz, Lorestan province, Iran. The cumin plants were sprayed twice during the season, before and after flowering (with a 10 day interval) according to the manufacturing Company. Three different types of Fe fertilization including Fe-nano-chelated (Fe-N), Fe-chelated (Fe-C) and Fe-siderophore (Fe-S) with the concentrations of 0 (control), 0.5 and 1 g/l were used for the experiment. Different plant parameters including grain Fe, crop yield, weight of 1000 grains, grain length, root length and stem length were determined. The highest yield of single plant was resulted by Fe-N1 (250 mg). Fe-N1 (3.8 g) and Fe-C1 (4.0 g) resulted in the highest weight of 1000 grains. However, the highest Fe concentration was related to treatment Fe-S1 (9.4 mg/kg). Plants treated with Fe-N (24.9 cm) and Fe-C (25.0 cm) treatments had the highest plant height. The highest root length was resulted by the Fe-N (8.9 cm) and Fe-C (9.1 cm) treatments. The control treatment resulted in the highest rate of root length/stem length (0.41). Treating the plants with Fe-C treatments resulted in the highest and significantly different grain length (6.8 mm). The concentration of 1 g/l of nano, chelated and siderophores were the most effective, significantly enhancing cumin yield and grain fortification. The results indicated the significant effects of Fe-N on plant yield and Fe uptake followed by the Fe-C method. The findings of this research work indicated that the Fe-N and the Fe-C methods were the most efficient methods enhancing cumin growth and yield. However, the most efficient method for seed fortification was the Fe-S method. The findings are of great nutritional, environmental and economical significance. [ABSTRACT FROM AUTHOR]

The agricultural and forestry productivity of Mediterranean ecosystems is strongly threatened by the adverse effects of climate change, including an increase in severe droughts and changes in rainfall distribution. In the present study, we performed a genome-wide association study (GWAS) to identify single-nucleotide polymorphisms (SNPs) and haplotype blocks associated with the growth and wood quality of Eucalyptus cladocalyx, a tree species suitable for low-rainfall sites. The study was conducted in a progeny-provenance trial established in an arid site with Mediterranean patterns located in the southern Atacama Desert, Chile. A total of 87 SNPs and 3 haplotype blocks were significantly associated with the 6 traits under study (tree height, diameter at breast height, slenderness coefficient, first bifurcation height, stem straightness, and pilodyn penetration). In addition, 11 loci were identified as pleiotropic through Bayesian multivariate regression and were mainly associated with wood hardness, height, and diameter. In general, the GWAS revealed associations with genes related to primary metabolism and biosynthesis of cell wall components. Additionally, associations coinciding with stress response genes, such as GEM-related 5 and prohibitin-3, were detected. The findings of this study provide valuable information regarding genetic control of morphological traits related to adaptation to arid environments.

Abstract: The activity of protein degradation enzymes in rodents under temperature stresses caused by a body temperature rise (hyperthermia) up to 42°С is studied under the conditions of hyperarid regions of arid territories. The heat stress was induced in a special chamber; water at a temperature necessary to raise or lower the body temperature passed through the chamber casing. Regardless of body temperature, the activity of neutral proteases (ANPs) of the liver decreases in both cases. The mechanisms leading to a decrease in ANP with an increase in body temperature are different, since the degree of decreased enzyme activity in this case is several times higher than with low-temperature stress. With hyperthermia, the ANP of all grades of thermal regime is significantly reduced, both in comparison with the control and with hypothermia, except for the incubation temperature of 10°C. The changes occurring in the rodent (in the liver) are evidence of the degree of influence of arid climatic conditions on the adaptability of the considered animals to climate warming. [ABSTRACT FROM AUTHOR]

This research was conducted to investigate yield and quality characteristics in the arid and irrigated conditions of different bread wheat cultivars in Tokat-Kazova conditions during the 2012-2013 growing season. Field experiments were established according to Randomized Complete Block Design as 3 replications with 10 bread wheat varieties in the arid and irrigated conditions. In the experiment, significant differences were obtained among cultivars in terms of investigated other traits except Zeleny sedimentation value in the arid conditions, grain yield, the number of spike per square meter and protein ratio in the irrigated and arid conditions. In the arid and irrigated conditions respectively the average of cultivars, heading period 170.9 and 170.1 day, the number of spike per square meter 599 and 677 number, thousand seed weight 41.3 and 45.1 g, spike length 9.1 and 9.2 cm, test weight 78.7 and 79.4 kg, grain yield 453.6 and 532.0 kg/da, protein ratio 8.7 and 8.5 %, Zeleny sedimentation value 41.7 and 36.0 ml, wet gluten 25.1 and 24.3 %, dry gluten 9.2 and 9.1 % and gluten index 46.7 and 51.6 % was determined. The Average grain yield was higher in the irrigated trial than in the arid trial. Also, higher values were obtained in terms of protein ratio, Zeleny sedimentation value, wet and dry gluten traits according to varieties grown in irrigated conditions from varieties in arid conditions in terms of quality. According to obtained results that the bread wheat cultivars can replace standard varieties in terms of yield and quality in the arid and irrigated trials were determined in the research at Tokat-Kazova. [ABSTRACT FROM AUTHOR]

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Potatoes are high-plastic plants that can be grown in almost all climates. In the Lower Volga, in the conditions of strong spring drought, high temperatures and soil throughout the growing season, lack of rainfall, potatoes can be grown only for irrigation. To obtain high and stable yields in these difficult conditions it is necessary to research varieties and its adaptation.

A pesar de ser fauna necrófaga y de estar presentes en cadáveres humanos, los Sarcophagidae no suelen utilizarse en estudios forenses debido a la dificultad en su identificación y la poca información sobre su biología. En este trabajo, se identificaron las especies de Sarcophagidae asociadas a cadáveres y se estudió su relación con los estados de descomposición. Se analizaron las preferencias por los sustratos cadavéricos (cerdo y llama) y las condiciones microambientales (sol y sombra) en un ambiente de altura (3.600 msnm), durante la primavera. Se utilizaron dos cadáveres de cerdo dispuestos al sol y a la sombra y un cadáver de llama dispuesto al sol. Se colectaron 597 individuos pertenecientes a cinco especies de Sarcophagidae: M. antofagastensis Mulieri, Mariluis & Aballay (n=347), M. quimaliensis (Lopes) (n=117), M. rusca (Hall) (n=32), M. penai (Lopes) (n=5) y M. aulacophyto Pape (n=96). Tanto M. antofagastensis, como M. quimaliensis fueron las únicas especies con colonización efectiva y representaron el 78% del total de adultos colectados. Microcerella antofagastensis fue la colonizadora primaria. Ambas especies respondieron de forma similar ante las condiciones microambientales y prefirieron el cadáver de cerdo. Se discute la importancia de M. antofagastensis y M. quimaliensis, como especies indicadoras y las posibles ventajas de la ovoviviparidad frente a otras especies ovíparas, en condiciones de extrema aridez.Despite their prevalence in human corpses during decomposition, Sarcophagidae are not frequently used in forensic studies due to the difficulty in their identification and to the lack of information on their biology. In this paper, we identified the species of Sarcophagidae associated to corpses and studied their relationship to decomposition stages. We analyzed preferences for different cadaveric substrates (pig and lama) and microenvironmental conditions (shade, sun) at a site located at 3600 m.a.s.l. during the spring. Two pig carcasses, one located in the shade and the other in the sun, and a third carcass of a lama located in the sun, were used. We collected 597 individuals belonging to five Sarcophagidae species: Microcerella antofagastensis Mulieri, Mariluis & Aballay (n=347), M. quimaliensis (Lopes) (n=117), M. rusca (Hall) (n=32), M. penai (Lopes) (n=5) and M. aulacophyto Pape (n=96). Both M. antofagastensis and M. quimaliensis were the effective colonizers and represented 78% of the total adults collected. Microcerella antofagastensis was the primary colonizer. Both species had a similar response against microenvironmental conditions and both preferred the pig carcass. We discuss the importance of these two species as forensic indicators and the advantages of ovoviviparity against other oviparous species under extreme arid conditions.

Sixteen male-sterile lines of pearl millet (Pennisetum glaucum (L.) R. Br.) found promising at CAZRI, Jodhpur were crossed with nine diverse restorers from different sources in this region, in a line x tester fashion to develop 144 hybrid combinations, with the objective to identify suitable A lines, R lines and hybrid combinations for arid Rajasthan. These hybrids were evaluated at three different locations in western Rajasthan (Tinwari, Pali and Jodhpur) during the rainy season of 2003. Eighteen promising hybrids based upon their performance over locations during 2003, were again evaluated in larger plots during the rainy season of 2004. Considering grain yield over all the five locations during the two seasons 2003 and 2004, ten high yielding hybrids were identified. Among these hybrids grain yield ranged from 1932 kg/ha to 2293 kg/ha, and flowering time from 43 to 48 days. The highest yielding hybrid was ICMA 96111 x RIB-3135-18 followed by ICMA 98333 x RIB-3135-18, ICMA 98222 x CZI 9621, ICMA 98004 x RIB-3135-18, ICMA 97555 x RIB-3135-18 and ICMA 95555 x H 77/833-2. It was observed that the restorer lines RIB-3135-18, CZI 9621, H77/833-2, CZI 1676-2, MIR 97171 and ICMR 356 gave high yielding hybrids. Similarly male sterile lines, ICMA 98222, ICMA 97555 and ICMA 98004 were involved in promising hybrid combinations. The hybrid ICMA 98222 x CZI 9621, which was one of the top five high yielding hybrids, ranked first in a multilocation trial conducted during the rainy season of 2005, at Jodhpur, Bawal, Durgapura and Bikaner, representing extreme arid conditions. This hybrid again recorded 12.8% and 6.6% higher grain yield over national checks GHB 538 and ICMH 356 respectively in Initial hybrid trial 2007, and was promoted to the Advance Hybrid and Population Trial for Kharif 2008.

The two-year field trial was established in May 2008 on light soil in the cadastre of Ratíškovice near Hodonín in an arid maize-growing production area. Prior to sowing selected soil conditioners were applied in experimental plots of an area of 864 m2 as follows: zeolite (a mineral of high sorption ca­pa­ci­ty), lignite (the youngest coal containing humus substances) and the supplementary soil substance agrisorb (polymer organic compound capable of holding in its structure and subsequently releasing water) and they were incorporated into a profile of 0.15 m. Including the untreated control the experiment involved 4 treatments. The rates of the conditioners were as follows: zeolite – 3 l . m−2, fraction used 1–2 mm; agrisorb – 20 g . m−2; lignite – 1000 g . m−2. Three types of clover-grass mixtures were sown: landscape mixture with an addition of leguminous plants (seeding rate 200 kg . ha−1), regional mixture (100 kg . ha−1) and annual mixture (70 kg . ha−1). The aboveground biomass taken from an area of 0.05 m2 was sampled in the stage of bud setting with three repetitions to each treatment. In 2008 and 2009 the respective treatments did not significantly change the contents of N, P, K, Ca and Mg in the aboveground biomass of the clover-grass mixtures. The differences in the contents of the macro elements were significant only between the individual types of mixtures and were due to their different botanical composition. Between the years 2008 and 2009 no significant differences were discovered among treatments in terms of the contents of P and K in none of the mixtures, but the Mg content decreased in the second year in most treatments by 50 relative % and more. The contents of N and Ca increased significantly in the second year in the regional and landscape mixtures; in the annual mixture also the Ca content. The year-on-year differences however were seen also in the untreated control showing the apparent effect of the year. A longer period of monitoring is necessary if we are to achieve an objective evaluation of the effect of the applied preparations on the chemical composition of the aboveground biomass.

Water shortage and heavy greenhouse gas emissions are threatening agricultural sustainability with food security severely, and becoming a major issue in arid areas. It is unclear whether improved farming systems on strip-intercropping integrated with no-tillage with straw returning and re-using old film practices can be developed to reduce soil nitrous oxide (N 2 O) emissions and boost crop yields for tackling those issues. A four-year field experiment for wheat-maize intercropping was carried on straw residue and film management of northwestern China in 2014–2017 and aimed to comprehensively assess crop yields and soil N 2 O emissions. The results showed that NTSMF (no-tillage with straw mulching and re-using old film), NTSSF (no-tillage with straw standing and re-using old film), and CTSF (conventional tillage with straw incorporation and mulching new film every year) treatments increased grain yields by 15.1%, 13.7%, and 12.8% respectively, compared to CTF (conventional tillage with no straw returning and mulching new film every year, the control treatment). NTSMF, NTSSF, and CTSF treatments had greater water use efficiency by 15.7%, 13.1%, and 14.2% than CTF, respectively. On the contrary, NTSMF and NTSSF treatments had lower soil N 2 O emissions (NE) by 23.9% and 20.4% than CTF, and lower by 19.8% and 16.0% than CTSF, respectively. No-tillage practice used more soil moisture and produced more grain yields but emitted less N 2 O than conventional tillage, NTSMF and NTSSF treatments reduced soil N 2 O emission per volume of evapotranspiration (WUE NE) by 23.6% and 20.9%, and reduced soil N 2 O emission intensity (NEI) by 33.9% and 30.0% in comparison to CTF. The better effect on the reduction of NE, WUE NE , and SEI was found in NTSMF, and the three indicators were successively decreased by 5.3%, 4.4%, and 6.9% over NTSSF in 2016–2017. NTSMF reduced NE and boosted GY was attributed to increased synchronicity of water demand and reduced adverse effects of soil temperature variations of both intercrops' strips. Our study concluded that grain yields were enhanced and soil N 2 O emissions were reduced by NTSMF treatment, and NTSMF treatment is a practical cropping production system for environmentally clean in an arid irrigated region. • The improved treatment on NTSMF with straw mulching in wheat strips and re-using old film in maize strips. • The improved treatment reduced soil N 2 O emissions (NE) and boosted grain yields (GY). • NTSMF reduced NE and boosted GY was attributed to increased synchronicity of water demand and reduced adverse effects of soil temperature variations. • NTSMF treatment is a practical cropping system for environmentally clean in arid irrigated areas. [ABSTRACT FROM AUTHOR]

Gene Expression Programming (GEP) was used to develop new mathematical equations for estimating daily reference evapotranspiration ( ET) for the Kingdom of Saudi Arabia. The daily climatic variables were collected by 13 meteorological stations from 1980 to 2010. The GEP models were trained on 65% of the climatic data and tested using the remaining 35%. The generalised Penman-Monteith model was used as a reference target for evapotranspiration (ET) values, with h varies from 5 to 105 cm with increment of a centimetre. Eight GEP models have been compared with four locally calibrated traditional models (Hargreaves-Samani, Irmak, Jensen-Haise and Kimberly-Penman). The results showed that the statistical performance criteria values such as determination coefficients ( R) ranged from as low as 64.4% for GEP-MOD1, where the only parameters included (maximum, minimum, and mean temperature and crop height), to as high as 95.5% for GEP-MOD8 with which all climatic parameters included (maximum, minimum and mean temperature; maximum, minimum and mean humidity; solar radiation; wind speed; and crop height). Moreover, an interesting founded result is that the solar radiation has almost no effect on ET under the hyper arid conditions. In contrast, the wind speed and plant height have a great positive impact in increasing the accuracy of calculating ET. Furthermore, eight GEP models have obtained better results than the locally calibrated traditional ET equations. [ABSTRACT FROM AUTHOR]

This paper presents the comparative anatomical and morphological characteristics of plants of two subgenera: Haworthia and Hexangularis. The study revealed two different strategies of adaptation to arid conditions of the growth of different subgenera of the genus Haworthia. Plants of the subgenus Haworthia adapted to arid conditions by increasing the accumulation of water, the presence of "windows", a smaller stoma size, and a thinner outer wall of the epidermis cells. On the other hand, plants of the subgenus Hexangularis adapted to arid conditions by reducing overheating and transpiration as well as by the presence of papillae and a thickened outer wall of the epidermis cells. [ABSTRACT FROM AUTHOR]

Mass gathering events commonly encounter environmental challenges that necessitate assurance of water quality and food security. The current outbreak of the coronavirus disease 2019 (COVID-19) call for maintaining safe drinking water supply and providing assessment tools of drinking water quality to avoid contamination in water sources or distribution networks. Arid environmental conditions also add more stress on supplied water to mass gathering events. Herein, we assess the quality of the water supply (desalinated 95% and groundwater 5%) in Makkah city, Saudi Arabia during a mass gathering event in 2019 (9.6 million people) for religious purposes. Fifty five samples were randomly collected from nine different districts of Makkah city, analyzed for TDS, turbidity, pH, EC, free Cl 2 , Al, Cd, Pb, Cr, F, major ions, coliform and E.coli bacteria and were finally used to estimate the water quality index (WQI). Major ions, trace elements and heavy metals analyses show values below permissible limits in most of the samples, while a few samples show slightly higher values. No bacterial count found in any sample. WQI values of all fifty-five samples were below 50 and were identified as "excellent water". The WQI variations could be attributed to the distribution network conditions rather than a direct impact of adding groundwater with uncontrolled chemical composition. The use of WQI to report the quality of water during mass gathering events to governmental authorities has been proved to be beneficial and should be applied for further mass gathering events worldwide. [ABSTRACT FROM AUTHOR]

Oilseeds are commonly used in human nutrition, feeding farm animals, industry, construction, medicine, and perfumery. They are a valuable source of high-nutrient protein, which is contained in the oil cake and meal obtained by processing the seeds into the oil. Sunflower and mustard are traditionally cultivated in the Lower Volga Region. Safflower, camelina, and oilseed flax have not become widespread there, which can be associated with the insufficient studies of them, the lack of proven technologies for farming, and the specific biochemical composition of the oil of their seeds. The objective of the research was to study the effects of the different planting densities on the duration of the developmental interphase periods, the morphological traits, and the crop yields under the soil and climate conditions in the arid zone of the Lower Volga Region. It has been determined that the average safflower yield under such conditions can reach 1.63 t per hectare with the Astrakhanskii-747 variety at the planting density of 300000 plants per hectare. [ABSTRACT FROM AUTHOR]

The key indices of soil biodiversity are considered in the context of a biogeocoenotic estimation of their role in the biosphere. The categories of soil biodiversity were determined with feature detection; the biosphere functions of soil biodiversity typical of arid conditions were differentiated. Biodiversity was first characterized on the basis of the internal properties of soils and the spatial indices of elementary soil areals. The contents of the parameters of internal and spatial soil organization make a certain contribution to the development of the concept of soil biodiversity and reflect the peculiarities of the modern stage of its development. [ABSTRACT FROM AUTHOR]