Semi-arid Conditions Research Articles

Response of durum wheat vs. bread wheat to Fusarium foot and root rot under semi-arid conditions

Response of durum wheat vs. bread wheat to Fusarium foot and root rot under semi-arid conditions

Effect of sowing dates, natural bio-stimulants, and micro-nutrients on the growth and seed yield of dry bean (Phaseolus vulgaris L.) under semi-arid conditions

Effect of sowing dates, natural bio-stimulants, and micro-nutrients on the growth and seed yield of dry bean (Phaseolus vulgaris L.) under semi-arid conditions

Evaluation of Aonla Varieties for Yield and Quality under Semi-Arid Conditions

This study, conducted at the Horticulture College and Research Institute for Women, Trichy, during 2023, aimed to assess the evaluation of Aonla (Indian gooseberry) under arid zone conditions of Trichy, focusing on yield and quality parameters. The experiment was laid out in Randomised Block Design (RRD) with 5 treatments as varieties and three replication. The varities are BSR 1, Krishna (NA 5), Kanchan (NA 4), NA 7, and Chakaiya. NA 7 is recommended for its high yield potential in limited spaces, aligning with the trend of high-density planting. BSR 1 excels in Total Soluble Solids, while Chakaiya stands out in acidity and ascorbic acid content. These insights guide cultivar selection for sustainable Aonla cultivation in semi-arid regions, crucial for meeting population demands.

Modeling Irrigation of Tomatoes with Saline Water in Semi-Arid Conditions Using Hydrus-1D

In arid and semi-arid regions like Tunisia, irrigation water is typically saline, posing a risk of soil and crop salinization and yield reduction. This research aims to study the combined effects of soil matric and osmotic potential stresses on tomato root water uptake. Plants were grown in pot and field experiments in loamy-clay soils and were irrigated with three different irrigation water qualities: 0, 3.5, and 7 dS/m. The Hydrus-1D model was used to simulate the combined dynamics of subsurface soil water and salts. Successful calibration and validation of the model against measured water and salt profiles enabled the examination of the combined effects of osmotic and matric potential stresses on root water uptake. Relative yields, indirectly estimated from actual and potential transpiration, indicated that the multiplicative stress response model effectively simulated the measured yields and the impact of saline water irrigation on crop yields. The experimental and modeling results provide information to aid in determining the salinity levels conducive to optimal crop growth. The findings indicate that the selected salinity levels affect tomato growth to varying degrees. Specifically, the salinity levels conducive to optimal tomato growth were between 0 and 3.5 dS/m, with a significant growth reduction above this salinity level. The gradual salinization of the root zone further evidenced this effect. The scenario considering a temperature increase of 2 °C had no significant impact on crop yields in the pot and field experiments.

Integration of Horse Manure Vermicompost Doses and Arbuscular Mycorrhizal Fungi to Improve Fruit Quality, and Soil Fertility in Tomato Field Facing Drought Stress.

Climate change poses major challenges for agriculture in arid and semi-arid regions, with drought conditions severely affecting water-intensive crops such as tomatoes. This study evaluates the efficacy of organic amendments, derived from horse manure, and arbuscular mycorrhizal fungi (AMF) on enhancing tomato (Solanum lycopersicum L.) fruit quality and soil health under semi-arid field conditions. The experimental design included two irrigation regimes (well-watered and drought stress) and two levels of vermicompost application (C1 5 t ha-1 and C2 10 t ha-1), applied individually or in combination with AMF. The results indicate that drought stress reduced tomato fruit growth and yield, while osmoprotectant accumulation, antioxidant enzyme activity, and bioactive compound levels increased, and the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity of tomato fruit also increased. Notably, the biostimulants application, especially (C1+AMF), counteracted the adverse effects of drought, compared to the control, by significantly enhancing fruit yields (60%), as well as increasing ascorbic acid levels (59%) and free amino acids content (90%). These treatments also improved the activity of bioactive compounds and nutrient uptake in the fruit. Furthermore, biostimulant application positively affected the physicochemical properties of soil. The results obtained confirm that the application of biostimulants can be suitable for improving crop sustainability and adaptability under conditions of water stress in semi-arid field regions.

Water productivity, yield response factors, yield and quality of alfalfa cultivars in semi-arid climate conditions

This study was carried out for 2 years (2020 and 2021) to elucidate the effects of water stress on yield and quality of alfalfa cultivars, to determine the water-yield and quality relations and the susceptibility of cultivars to water stress. Three different irrigation treatments (100%, 75% and 50% of full irrigation, I100, I75 and I50) and 12 different alfalfa cultivars (SHN, Osmanağa, Şahin 42, Minerva, Elçi, Riviera Vicentina, Magna 601, Magnum V, Prosementi, Ezzelina, Sunter, Nimet) were used in present experiments conducted in randomized-blocks split-plots design with 3 replications to investigate effects of irrigation levels on water, yield and quality parameters of alfalfa. Present findings revealed that water stress decreased crop water productivity, but increased irrigation water productivity of alfalfa cultivars. Herbage yields of the cultivars varied between 48.20 and 64.98 t/ha, hay yields between 11.42 and 14.67 t/ha and protein yields between 2.22 and 3.07 t/ha. Alfalfa was found to be sensitive to water stress in terms of herbage yield, but more tolerant in terms of hay and protein yields. Morphological characteristics (plant height, number of stems per plant, number of main stem branches and root crown diameter) decreased with increasing water stress levels. In terms of quality traits, while acid detergent fiber (ADF), neutral detergent fiber (NDF), crude fiber and crude ash ratios increased, crude protein ratios decreased with increasing irrigation water levels. It was concluded based on present findings that water stress resulted in different responses of different alfalfa cultivars and although it increased quality traits in general, it decreased herbage, hay and protein yields. Again, based on present findings, Magna 601 cultivar could be recommended for semi-arid regions.

Geoinformatics-Based Mapping of Environmental Sensitive Areas for Desertification over Satara and Sangli Districts of Maharashtra, India

Desertification processes in arid, semi-arid, and dry sub-humid conditions have been enhanced in recent decades. The geospatial database and associated satellite data can be effectively employed for regional planning to address desertification and land degradation. In this study, the Mediterranean Desertification and Land Use (MEDALUS) model has been used to map environmentally sensitive areas due to desertification in the Satara and Sangli districts of Maharashtra, India. This was achieved by combining Landsat-8 multispectral data, Census data, soil data, and climatic variables like temperature, rainfall, and evapotranspiration. The algorithm of MEDALUS is the geometric mean of four indicators, namely soil quality index (SQI), climate quality index (CQI), vegetation quality index (VQI), and socio-economic quality index (SEQI). The findings indicated that the majority of the study area comes under the potential category of desertification (60.32%) followed by fragile (27.87%) and critical (11.81%). Areas with a high propensity for desertification were found over the low to very low climatic quality and moderate to high soil quality including lower socio-economic quality. The lower socio-economic quality is mainly due to high to very high population density (>100 people/km2), low to moderate illiteracy rate (<16%), and low to moderate work participation rate (<50%) that incentivize unsustainable land use practices. The study provides a valuable tool for understanding and managing natural resources. It offers a detailed analysis of the environmental sensitivity of the study area, taking into account various factors like land use, vegetation cover, slope, and soil erosion potential. The developed comprehensive map of the area helps in identifying the most sensitive regions and developing appropriate conservation strategies. The information obtained from the study can be utilized to develop and implement successful measures to prevent or alleviate desertification, which is crucial for sustaining the health of ecosystems and the welfare of local residents.

Impact of reclaimed wastewater on alfalfa production under different irrigation methods

ABSTRACT The effect of different irrigation methods (sprinkler, surface, surface-drip, and subsurface-drip) using treated wastewater, on alfalfa yield quantity and quality, was studied under semi-arid conditions. Randomized complete block design considering irrigation methods on 5 × 5 m plots replicated four times. Applied irrigation water was based on the Penman–Monteith equation using the FAO Cropwat software and accounting for the efficiencies of used irrigation systems. Surface irrigation gave the highest alfalfa fresh yield without significant difference compared to subsurface-drip. Average fresh production was 123, 120, 109, and 91 tons/h for surface, subsurface-drip, surface-drip, and sprinkler irrigation, respectively. Alfalfa fresh weight from subsurface-drip irrigation was 32 and 10% higher compared to sprinkler and surface-drip irrigation. Alfalfa dry weight from subsurface-drip irrigation was 10, 21, and 47% higher compared to surface-drip, surface, and sprinkler irrigation, respectively. N percentage in alfalfa leaves was significantly lower by 12% under subsurface-drip irrigation as compared to the other irrigation methods. Escherichia coli (E. coli) and fecal coliform (FC) were not detected on alfalfa leaves using subsurface-drip irrigation. E. coli and FC counts were high on leaves using sprinkler and surface irrigation. Subsurface-drip irrigation may be adapted as an efficient irrigation method when using non-conventional water under semi-arid conditions.

Soil Chemical Properties and Nutrient Dynamics under Different Legume-based Agroforestry Systems in Semi-arid Conditions of Haryana

Background: In order to support livelihoods, enhance food security, restore ecosystem services, and reduce pressure on forests, soil fertility can be improved by utilizing alternative land-use systems, such as agroforestry. Methods: The present study was conducted to investigate the effect of different agroforestry systems on soil chemical properties and nutrient availability (macro and micro) during different seasons in Hisar, Haryana. Different systems include Poplar (Populus deltoides), Eucalyptus (Eucalyptus tereticornis), Melia (Melia composita), Shisham (Dalbergia sissoo) based agroforestry system (Cowpea-Wheat) and sole cropping of Cowpea-Wheat (as control). Soil samples were collected from 0-15 and 15-30 cm of soil depth during five seasons i.e., winter, spring, summer, rainy and autumn. Result: Soil EC, SOC and available macronutrients and micronutrients were significantly affected by the depth of sampling, systems and seasons while soil pH was not significantly affected by seasons. Lower soil pH and EC was observed from agroforestry systems as compared to sole cropping. Soil Organic Carbon, availability of N, P, K and S was significantly higher under tree based systems as compared to control. Maximum DTPA extractable Mn, Zn and Cu was observed under poplar based system while highest DTPA extractable Fe was observed under Melia based system during both the years. Significantly higher SOC and nutrient availability was observed during autumn, rainy and spring seasons as compared to winter and summer seasons, while reverse trend was observed for soil pH and EC among the seasons. Soil Organic Carbon, availability of macro and micronutrients decreased with increase in soil depth. Overall, the soil chemical properties and nutrient status of soil were comparatively better under tree based systems than sole cropping of Cowpea-Wheat.

Hydroponic Screening at Early Seedling Stage Identified Sources of Salinity Tolerance in Wheat (Triticum aestivum L.) Crop

Wheat is a vital crop globally, essential for agriculture, economics, and food security. However, in arid and semi-arid conditions, wheat production faces significant challenges due to low water availability, uneven rainfall distribution, and high soil salinity. The germination and early seedling stages are particularly vulnerable to these stresses. Therefore, this study assessed 15 wheat genotypes for their tolerance to salinity stress during early growth stages, using a hydroponic system with four salt stress levels (0, 50, 100, and 150 mM NaCl). Significant differences were observed for genotype and salinity main effects and their interaction on all investigated traits, indicating considerable variability in the response to salt stress among the investigated wheat cultivars. High NaCl concentrations led to substantial reductions in measured parameters across genotypes, with some showing resilience while others exhibited heightened sensitivity. Stress tolerance indices, such as mean productivity (MP), geometric mean productivity (GMP), harmonic mean (HM), stress tolerance index (STI) and yield index (YI), were identified as reliable indicators for selecting salt-tolerant wheat cultivars. Consequently, Sidi Okba (G11), Ziad (G12), Tamezghida (G13) and Zidane (G14) emerged as the most promising, displaying acceptable performance under both non-stress and salt-stress conditions. These genotypes could serve as valuable genetic resources for breeding programs aimed at enhancing wheat’s salinity tolerance, particularly in arid and semi-arid regions.

Phytochemical Investigation of Parthenium hysterophorus and its Antibacterial Activity

Parthenium hysterophorus, which is an invasive weed.it is Native of Mexico,comes under Asteraceae. Our study Area is at Hameedganj,which is a village comes in sehore district.Parthenium is a species of flowering plant , its leaves looks like carrot leaf so it is also known as Carrot Grass.its pollen are very harmful and causes itching when it is touched. It spreads very fast and cause harm to useful crops like Wheat.its adaptability is very high preferring semi arid and dry conditions. Once it grows, it spreads very fast, so Globally various weed control strategies are applied to control its population but there are certain limitation with conventional methods. So Management of parthenium is a Global problem and still remains a focused view Our research is to investigate its phytochemical analysis and its Antibacterial property,so that it can be managed and used Economically.

Effect of hydrogel on survival and growth of Grevillea robusta seedlings under semi-arid field condition

Water scarcity limits the survival and growth of planted-out seedlings in Ethiopia’s semi-arid regions. Hydrogel, recently introduced in Ethiopia, is a super-absorbent polymer to reduce water stress. This study investigated its effect on the early survival and growth of Grevillea robusta seedlings in semi-arid areas. Relevant soil characteristics were analyzed. Four hydrogel levels (control, 3, 5, and 7 g/plant) were applied to the bottom of planting holes in a randomized complete block design with three replicates. Survival, Height, and Root Collar Diameter were measured at 6 and 14 months after planting. One-way ANOVA assessed hydrogel effects. No significant positive effects of hydrogel on survival or early growth compared to the control (0 g/plant) were observed in the sandy-loam soil. These findings suggest limited benefit under the study’s specific conditions. Further research is crucial to explore the potential of hydrogels, considering broader ranges of application rates and methods, tree species, and environmental conditions. This knowledge may support forest restoration efforts in the face of severe land degradation, climate change, and variability in Ethiopia.

Assessment of agro-physiological traits for identifying drought-tolerant durum wheat (Triticum durum Desf.) genotypes under rainfed conditions

Breeders are focused on developing high-yielding genotypes that can grow in semi-arid regions under water stress. A field experiment was conducted during the 2020 to 2021 cropping season at the experimental field of ITGC, Setif. The aim of this study was to assess the performance of durum wheat genotypes for agronomic traits growing under semi-arid conditions. The 10 genotypes evaluated were grown in a randomized block with three replications. Analysis of variance showed that the genotype effect was significant for most parameters studied. The best grain yield was recorded for genotypes G3 (3.52 t ha-1) G2 (3.48 t ha-1), and G5 (2.89 t ha-1); thus, they maintained the highest water content (81.09, 84.95, and 84.34%, respectively) and lower temperatures under these conditions. Simple linear regression showed that grain yield correlated positively with the number of spikes, and the number of grains per spike. The principal component (PC) analysis classified both genotypes G2 and G3 as high grain yielding genotypes; by contrast, genotypes Jupare C 2001, Bouatleb, and G1 were low-yielding.

Regulated Deficit Irrigation to Boost Processing Tomato Sustainability and Fruit Quality

Improving water use efficiency is gaining relevance for the sustainability of agricultural practices. In semi-arid Mediterranean areas, recent studies highlighted that future climatic scenarios will be even more critical for crops, given the increase in water scarcity. In this context, the rationalization of irrigation water is necessary to sustain processing tomato (Solanum lycopersicum L.) yield and quality since this crop requires large volumes of water. The present research aimed to identify the effects of a regulated deficit irrigation (RDI) strategy on the environmental and economic sustainability and fruit technological and functional quality of the processing tomato crop in the Mediterranean area. A two-year, open-field experiment was carried out to compare full irrigation management (IRR, restoring 100% ETc) with an RDI strategy based on restoring 50% ETc when the first fruit cluster reached the typical size (BBCH 701 phenological stage, relative to Solanaceous fruits). Remarkable water saving (21.46%, average of the two years) was achieved under RDI without significant variations in total and marketable yield compared to the IRR regime. Consequently, improved economic water productivity (+23.17%) was observed, allowing enhanced processing tomato sustainability. The RDI strategy boosted the glucose content (+17.78%), soluble solids content (SSC, +10.17%), and dry matter of the fruits (+10.03 g%). Furthermore, a higher SSC-to-titratable acidity ratio (+15.47%) and a negative shift in fructose/glucose balance (−7.71%) were observed in RDI-treated plants. Higher levels of the drought stress markers proline (+38.99%) and total polyphenols (+20.58%) were detected in RDI- compared to IRR-irrigated tomato fruits. These findings suggested the RDI strategy as an effective and sustainable approach for increasing both water productivity and the fruit quality of the processing tomato crop under semi-arid Mediterranean climatic conditions.

Stable isotope evidence for long-term stability of large-scale hydroclimate in the Neogene North American Great Plains

Abstract. The Great Plains of North America host a stark climatic gradient, separating the humid and well-watered eastern US from the semi-arid and arid western US, and this gradient shapes the region's water availability, its ecosystems, and its economies. This climatic boundary is largely set by the influence of two competing atmospheric circulation systems that meet over the Great Plains – the wintertime westerlies bring dominantly dry air that gives way to moist, southerly air transported by the Great Plains low-level jet in the warmer months. Climate model simulations suggest that, as CO2 rises, this low-level jet will strengthen, leading to greater precipitation in the spring but less in the summer and, thus, no change in mean annual precipitation. Combined with rising temperatures that will increase potential evapotranspiration, semi-arid conditions will shift eastward, with potentially large consequences for the ecosystems and inhabitants of the Great Plains. We examine how hydroclimate in the Great Plains varied in the past in response to warmer global climate by studying the paleoclimate record within the Ogallala Formation, which underlies nearly the entire Great Plains and provides a spatially resolved record of hydroclimate during the globally warmer late Miocene. We use the stable isotopes of oxygen (δ18O) as preserved in authigenic carbonates hosted within the abundant paleosol and fluvial successions that comprise the Ogallala Formation as a record of past hydroclimate. Today, and coincident with the modern aridity gradient, there is a sharp meteoric water δ18O gradient with high (−6 ‰ to 0 ‰) δ18O in the southern Great Plains and low (−12 ‰ to −18 ‰) δ18O in the northern plains. We find that the spatial pattern of reconstructed late Miocene precipitation δ18O is indistinguishable from the spatial pattern of modern meteoric water δ18O. We use a recently developed vapor transport model to demonstrate that this δ18O spatial pattern requires air mass mixing over the Great Plains between dry westerly and moist southerly air masses in the late Miocene – consistent with today. Our results suggest that the spatial extents of these two atmospheric circulation systems have been largely unchanged since the late Miocene and any strengthening of the Great Plains low-level jet in response to warming has been isotopically masked by proportional increases in westerly moisture delivery. Our results hold implications for the sensitivity of Great Plains climate to changes in global temperature and CO2 and also for our understanding of the processes that drove Ogallala Formation deposition in the late Miocene.

Assessing groundwater quality in semi-arid conditions: a geographic information systems-integrated approach using water quality index

Meeting freshwater demands in water-scarce regions is imperative, given challenges like hydric stress, urbanization, aridity, and population growth. This study focuses on the Tebessa aquifer system, a critical water source facing escalating demands. A primary objective is to identify actionable management strategies to improve groundwater quality dynamics in semi-arid regions. The methodology involves a comprehensive assessment of groundwater health using the Water Quality Index (WQI) approach. This method integrates diverse parameters influenced by intensive agricultural and industrial activities. Additionally, spatial relationship analysis, facilitated by Geographic Information System (GIS) technology, is employed to gain insights into complex hydrogeological processes. The multi-parameter strategy implemented results in water quality maps that highlight various ions, revealing spatial disparities and assigning quality priority classes from 'Good' to 'Poor' across the groundwater. The research, conducted in the semi-arid Tebessa-Morsott Plain, encompasses field and laboratory investigations to delineate hydrochemical traits, including alkalinity, salinity, and heightened ion concentrations. The results of the study contribute to scientific understanding by uncovering interrelationships and spatial intricacies, offering valuable insights for water resource governance. The effectiveness of the methodology, incorporating WQI and GIS, is demonstrated in the comprehensive evaluation of groundwater quality. Ultimately, this research provides a foundation for informed decision-making and sustainable management of groundwater resources in semi-arid regions.

Age and environmental conditions for the formation of the Pannonian mega-yardang system

The Pannonian mega-yardang system is the northernmost mega-yardang field in Europe, exerting a profound influence on the relief and surface hydrographic structure of Western Hungary. Despite its significance, the precise timing and climatic conditions under which this mega-yardang system formed remain elusive. The geological setting was studied, the former humidity and biome patterns were modelled, the climatically analogous regions of the past climates of the region were identified, and the Köppen Aridity Indices of the region were compared to the aridity values of other yardang fields from five continents in the last 3.3 mys. The geological structure of the yardangs suggests an origin post-dating the Tortonian period but preceding the mid-Pleistocene era. In the Zanclean and in the warmer periods of the Piacenzian, the studied region had humid subtropical climatic conditions that were not suitable for the formation of large-scale aeolian landforms. Similarly, in the Quaternary period, the climate varied between boreal and humid continental, which was not conducive to the formation of mega-yardang fields. Cold semi-arid climatic conditions only existed in the mid-Pliocene cold period and perhaps at the transition of the Pliocene to the Pleistocene. This paleoclimatic hypothesis is in accordance with the Pliocene fossil record of the region, which contains the remains of such arid habitat-dwelling fauna elements as camelids and struthionids. The comparison of the development of Köppen Aridity Indices among yardangs in other territories also suggests that the Pannonian mega-yardang system may have formed around the transition of the Neogene to the Quaternary epochs.Graphical abstract

Improving prediction accuracy of CSM-CERES-Wheat model for water and nitrogen response using a modified Penman-Monteith equation in a semi-arid region

Context or problemThe implementation of crop models for water and nitrogen management are important in preserving water resources and reducing groundwater pollution. The Decision Support System for Agrotechnology Transfer (DSSAT) is a collection of field-scale process-based crop models that simulate crop growth and yield in response to water and nitrogen management as well as many other factors. Objective or research questionThe objective of this study was to improve the simulation of irrigation and nitrogen fertilizer effects on growth and yield of winter wheat using locally modified Penman-Monteith (PM) equation. Specifically, we focused on improving the estimation of ETo using a locally modified Penman-Monteith (PM) equation in the CSM-CERES-Wheat model. MethodsField measured data from a two-year experiment (2009–2010 and 2010–2011) in a semi-arid region were used to calibrate and evaluate the CSM-CERES-Wheat model in a region with strong advective condition. In this experiment, the irrigation treatments were 1.2, 1.0, 0.8, 0.5 times by full irrigation requirements and rain-fed, and nitrogen treatments were 0, 46, 92, and 136 kg N ha−1. ResultsUsing the CSM-CERES-Wheat model with the unmodified PM equation resulted in some growth variables such as: aboveground dry matter, grain yield, and grain nitrogen uptake with high normalized root mean square error (NRMSE) of 0.51, 0.35, and 0.32, respectively. However, using the modified PM equation for ETo module under semi-arid condition improved the soil water content estimation and the model outputs, such as the above ground dry matter, grain yield and grain nitrogen uptake with NRMSE of 0.2, 0.15 and 0.16, respectively, that are accurate. This modification provided more accurate estimations, particularly in our experimental site in semi-aid region with strong advective conditions. ConclusionsThe findings of this study indicated that the locally modified PM equation in the CSM-CERES-Wheat model enhanced the accuracy of estimating irrigation and nitrogen fertilizer on the growth and yield of winter wheat. By improving the estimation of ETo value, the model's performance in simulating crop responses to water and nitrogen management was significantly enhanced. Implications or significanceThe utilization of the accurately estimated ETo value of the modified PM equation has significant importance in the practical application of the CSM-CERES-Wheat model. Furthermore, this modification greatly enhances the accuracy of model outputs, particularly at our experimental site located in a semi-arid region with robust advective conditions.

Evaluation of the fully coupled WRF and WRF-Hydro modelling system initiated with satellite-based soil moisture data

ABSTRACT This study comparatively evaluates the skill of the (un)coupled Weather Research and Forecasting (WRF) – WRF-Hydro system supported with satellite-based soil moisture initiation in long-term simulations of hydrometeorological variables under humid and semi-arid climate conditions. Prior to the coupling, the WRF-Hydro model is calibrated using streamflow data at different data scales (i.e. hourly and daily) to discuss the influences of the changing temporal resolution of the reference dataset on the optimum parameter values. According to the results, fully coupled models correct the location and magnitude of the occurrence of hourly extreme precipitation. Changing the initial soil moisture data source affects the terrestrial water cycle elements in the semi-arid region (i.e. Mediterranean (MED)) more than in the humid area (i.e. Eastern Black Sea (EBS)), especially in spring and summer. The initiation of the coupled model with satellite-based soil moisture improves the streamflow outputs after a reasonable spin-up period for the MED region.

Evaluation of the soil carbon sequestration potential and toward digital soil mapping under semi-arid Mediterranean ecological condition

Evaluation of the soil carbon sequestration potential and toward digital soil mapping under semi-arid Mediterranean ecological condition