Carbonaceous aerosols (CA) strongly impact regional and global climate through their light-absorbing and scattering properties, yet their effects remain uncertain in dust-influenced regions. We investigated the optical properties, source contributions, and radiative impacts of CA at two climatically distinct regions in northwestern India: an arid region (AR, Jodhpur; post-monsoon) and a semi-arid region (SAR, Kota; winter). Mean absorption & Aring;ngstr & ouml;m exponent (AAE) values were comparable between the two regions (AR: 1.416 +/- 0.173; SAR: 1.395 +/- 0.069), but temporal cluster analysis revealed source-specific variability, with lower AAE during traffic-dominated periods (similar to 1.30) and elevated AAE during solid fuel and biomass combustion (1.68 in AR and 1.52 in SAR). While equivalent BC (eBC) levels were higher in AR with a relatively uniform liquid-fuel contribution (BClf = 80.06 +/- 1.98 %), the mass absorption cross- of BC (MAC(BC)) in SAR was similar to 4.5X greater, driven by local solid fuel combustion and transported biomass burning emissions (BCsf = 34.61 +/- 6.88 %). Mie modelling indicated higher SSA in AR due to higher contribution of mineral dust, in contrast to SAR, where carbonaceous aerosols caused stronger absorption, forward scattering, and higher imaginary refractive index (k(OBD)). Although absorption enhancement (E-lambda) was slightly higher in AR (similar to 1.11 vs. similar to 0.99), SAR aerosols nearly doubled the warming potential (Delta RFE), with RFE values of similar to 0.87 W/m(2) in SAR versus similar to 0.43 W/m(2) in AR. These findings highlight strong source-specific and site-specific variability in aerosol absorption and radiative, emphasizing the need to integrate region-specific parameters into climate models and air quality assessments for data-scarce arid and semi-arid South Asian environments.

Aerosol optical properties and radiative forcing critically influence Earth's climate, particularly in semi-arid regions. This study investigates these properties in Yinchuan, Northwest China, focusing on aerosol optical depth (AOD), single-scattering albedo (SSA), & Aring;ngstr & ouml;m Index, and direct radiative forcing (DRF) using 2023 CE-318 sun photometer data, HYSPLIT trajectory analysis, and the SBDART model. Spring AOD peaks at 0.58 +/- 0.15 (500 nm) due to desert dust, with coarse-mode particles dominating, while summer SSA reaches 0.94, driven by fine-mode aerosols. Internal mixing of dust and anthropogenic aerosols significantly alters DRF through enhanced absorption, with spring surface DRF at -101 +/- 22W m-2 indicating strong cooling and internal mixing increasing atmospheric DRF to 52.25W m-2. These findings elucidate dust-anthropogenic interactions' impact on optical properties and radiative forcing, offering critical observations for semi-arid climate research.

The negative impact of climate change is potentially damaging agroecosystem services that have constrained agricultural production and caused water scarcity in Central Asian countries, particularly in Uzbekistan. This study evaluates the efficiency of full (FDI) and deficit (DDI) drip irrigation regimes for amaranth (Amaranthus spp.) cultivation in the Tashkent region of Uzbekistan using the HYDRUS-1D simulation model. Field experiments were conducted over two growing seasons, accompanied by soil moisture monitoring, root zone analysis, and crop performance measurements while the accuracy of the obtained results was assessed against ground measured data. The results showed that compared to the FDI regime, amaranth under the DDI improved water productivity by 56.5% while exhibiting tolerance to water scarcity. The Pearson correlation analysis revealed a strong relationship between the simulated and observed SWC data for both irrigation regimes (R2 = 0.862 for FDI and R2 = 0.936 for DDI), indicating the model's predictive reliability. Although FDI produced higher yield (2004 kg/ha) over the two-year period, which was 25% (2 t ha-1) higher than the DDI regime (1,604 kg/ha). However, DDI demonstrated significantly greater water productivity (56.5% higher), attributed to reduced unproductive evaporation and the C4 nature of amaranth. Root system analysis revealed deeper penetration under DDI, suggesting adaptive responses to water stress. The findings of this study suggest that implementing precise irrigation technology in amaranth cultivation combined with the use of the HYDRUS-1D model in the context of inevitable climate change, can ensure the long-term sustainable management of water and land resources in arid regions.

Flash floods are highly destructive natural disasters, particularly in arid and semi-arid regions like Egypt, where data scarcity poses significant challenges for analysis. This study focuses on the Wadi Al-Barud basin in Egypt's Central Eastern Desert (CED), where a severe flash flood occurred on 26-27 October 2016. This flash flood event, characterized by moderate rainfall (16.4 mm/day) and a total volume of 8.85 x 106 m3, caused minor infrastructure damage, with 78.4% of the rainfall occurring within 6 h. A significant portion of floodwaters was stored in dam reservoirs, reducing downstream impacts. Multi-source data, including Landsat 8 OLI imagery, ALOS-PALSAR radar data, Global Precipitation Measurements-Integrated Multi-satellite Retrievals for Final Run (GPM-FR) precipitation data, geologic maps, field measurements, and Triangulated Irregular Networks (TINs), were integrated to analyze the flash flood event. The Soil Conservation Service Curve Number (SCS-CN) method integrated with several hydrologic models, including the Hydrologic Modelling System (HEC-HMS), Soil and Water Assessment Tool (SWAT), and European Hydrological System Model (MIKE-SHE), was applied to evaluate flood forecasting, watershed management, and runoff estimation, with results cross-validated using TIN-derived DEMs, field measurements, and Landsat 8 imagery. The SCS-CN method proved effective, with percentage differences of 5.4% and 11.7% for reservoirs 1 and 3, respectively. High-resolution GPM-FR rainfall data and ALOS-derived soil texture mapping were particularly valuable for flash flood analysis in data-scarce regions. The study concluded that the existing protection plan is sufficient for 25- and 50-year return periods but inadequate for 100-year events, especially under climate change. Recommendations include constructing additional reservoirs (0.25 x 106 m3 and 1 x 106 m3) along Wadi Kahlah and Al-Barud Delta, reinforcing the Safaga-Qena highway, and building protective barriers to divert floodwaters. The methodology is applicable to similar flash flood events globally, and advancements in geomatics and datasets will enhance future flood prediction and management.

Approximately 3.44 billion tons of copper mine tailings (MT) were produced globally in 2018 with an increase of 45% from 2010. Significant efforts are being made to manage these tailings through storage facilities, recycling, and reuse in different industries. Currently, a large portion of tailings are managed through the tailing storage facilities (TSF) where these tailings undergo hydro-thermal-mechanical stresses with seasonal cycles which are not comprehensively understood. This study presents an investigative study to evaluate the performance of control and cement-stabilized copper MT under the influence of seasonal cycles, freeze-thaw (F-T) and wet-dry (W-D) conditions, representing the seasonal variability in the cold and arid regions. The control and cement-stabilized MT samples were subjected to a maximum of 12 F-T and 12 W-D cycles and corresponding micro-and-macro behavior was investigated through scanning electron microscope (SEM), volumetric strain (epsilon v), wet density (r), moisture content loss, and unconfined compressive strength (UCS) tests. The results indicated the vulnerability of Copper MT to 67% and 75% strength loss reaching residual states with 12 F-T and 8 W-D cycles, respectively. Whereas the stabilized MT retained 39%-55% and 16%-34% strength with F-T and W-D cycles, demonstrating increased durability. This research highlights the impact of seasonal cycles and corresponding strength-deformation characteristics of control and stabilized Copper MT in cold and arid regions. (c) 2025 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/

Ecological restoration of abandoned mining areas in arid regions presents significant challenges, especially in terms of soil salinization, vegetation loss, and limited water resources. In the Hami arid area of Xinjiang, vegetation restoration is crucial for stabilizing ecosystems and combating land degradation. This study investigated the effects of two irrigation methods-drip and border irrigation-on the growth and survival of four plant species: Tamarix chinensis, Calligonum mongolicum, Haloxylon ammodendron, and Phragmites australis, each exposed to salinity levels of 8 g/L, 12 g/L, and 16 g/L. Our results showed that drip irrigation significantly improved the growth and survival outcomes for most species, particularly T. chinensis and H. ammodendron, with average heights, crown sizes, and base diameters substantially higher under drip irrigation compared to border irrigation (p < 0.05). C. mongolicum, however, displayed optimal vertical growth under border irrigation, although drip irrigation promoted a denser, more compact crown structure. Salinity tolerance varied by species, with 8 g/L salinity being optimal for all, while higher salinity levels (12 g/L and 16 g/L) reduced growth across species, underscoring the importance of salinity management in restoration efforts. P. australis, assessed only under border irrigation due to its high water requirements, showed stable growth but reduced tolerance at higher salinities. These findings highlight that drip irrigation, particularly when combined with moderate salinity (8 g/L), is a more effective strategy for enhancing vegetation growth and survival in arid, saline environments. Our study provides practical recommendations for irrigation and salinity management in ecological restoration, offering insights for improving vegetation resilience in arid mining landscapes.

In this study, we investigated the aerosol radiative forcing (ARF) using ground-based measurements of PM2.5 and black carbon aerosols at a semi-arid, rain shadow location, Solapur in peninsular India. It is observed that aerosols caused a net cooling effect at top of the atmosphere (TOP) indicating that the aerosols reflect more solar radiation back to space than they absorb. At the surface, the aerosols caused a net cooling effect indicating more presence of scattering type aerosols. The resulting ARF of the aerosols was found to be ranging from +38 Wm-2 in monsoon to +53 Wm-2 in pre-monsoon indicating trapping of energy which resulted in a warming of the atmosphere. However, BC -only forcing indicated a significant warming effect at TOP as well as in the atmosphere which showed the potential of the absorbing carbonaceous aerosols. Overall, BC was responsible for 44% and 32% of the composite ARF, even though it formed only 7% and 2% of composite aerosol in the dry and wet periods, respectively. The warming impact of BC aerosols was also manifested in terms of their contribution to aerosol radiative forcing efficiency (ARFE) which was about four times more for BC-only than that for composite aerosols. More atmospheric heating rates were observed during dry periods for composite and BC-only aerosols than during wet period. These findings have important implications for aerosol-cloud-precipitation studies as well as the atmospheric thermodynamics and hydrological cycle over this semi-arid region where the total aerosol load is not significant and rainfall amount is scarce.

Debris flows can develop into mega catastrophes in semi-arid regions when the source materials come from landslides, and both snowmelt and precipitation are involved in increasing water discharge. In such environments, the formation of large-scale debris flows exhibits a distinguishable pattern, in which a multi-fold lower triggering rainfall threshold holds compared to humid regions. Previous research mainly focuses on mechanisms in humid environments or neglects variations across aridity classes. In this study, the formation and evolutionary mechanism of a debris flow occurring in a semi-arid context is investigated via field surveys, granularity measurement, terrain and climate analyses, and snow cover change detection. By examining the July 22, 2021, Xiao Dongsuo debris flow at Amidongsuo Park in the Qilian Ranges on the northeastern margin of the Tibetan Plateau, the mechanism of debris flows in semi-arid regions is revealed. The research finds that the large debris flow, whose course erosion scales up the disaster by 0.12 million m3, is primarily supplied by landslide deposits of 1.16 million m3. The debris flow is empowered by the integrated flow of extreme precipitation and extreme heat-stimulated snowmelt. However, the precipitation required to trigger the debris flow is much lower than that of precipitation-dominated ones and those in humid regions. In semi-arid mountains, prolonged extreme heat tends to increase soil moisture in areas covered by snow or permafrost. This reduces slope stability and induces slope failures, amplifying the disaster magnitude and raising disaster risks through extended deterioration. Hence, this study inspects the failure mechanism associated with debris flows in semi-arid regions for a more comprehensive understanding to constitute viable control plans for analogous disasters.

Soil-borne pathogens have economic significance regarding the damage they cause to crop production worldwide. Arid lands are even more susceptible to soil-borne pathogens damage due to climate extremes such as high temperature and evapotranspiration to precipitation ratio that limits the diversity of crops. More so, some soil-borne pathogens are highly adapted to arid lands' high soil temperature and water limitations. Chemical controls like fungicides and bactericides are widely used in managing soil-borne diseases, but they come at a significant environmental, health, and agricultural cost. On the other hand, biological control of soil-borne pathogens is relatively environment-friendly, safe, has no reported effect on human and animal health, and can improve soil health for optimum ecosystem functioning. Thus, this review presents an overview of soil-borne pathogens infestation in arid lands and the potential of using biological control agents (BCAs) in managing plant disease outbreaks. Some common pathogens in arid lands include Fusarium spp. (pathogenic), Pythium spp., Rhizoctonia solani, and Meloidogyne incognita. Investigations have, however, revealed effective BCAs against soil-borne pathogens, and some examples include Bacillus cereus, Streptomyces atrovirens, Phlebiopsis gigantea, Pseudomonas putida, Trichoderma harzianum, Pythium oligandrum, and Enterobacter amnigenus. The most common mechanisms used by BCAs for controlling soil-borne pathogens include antibiosis, induced systemic resistance, parasitism (mycoparasitism), antagonism, competition for nutrients and space, and indirect plant growth promotion. Recent advances in molecular biology, such as metabarcoding and biomarker transformation, offer promising ways to increase the success rates with the use of BCAs under field conditions. This study suggests that the effectiveness of BCAs can be further enhanced with the addition of soil organic amendments coupled with the cultivation of arid lands adapted crops such as agave and Opuntia spp.

This study aims to investigate the quantitative relationship between resistivity and the physical and mechanical properties of soil in different types of herbaceous slopes in the alpine arid and semi-arid loess area. The research is conducted in the self-built test area of Changlinggou Basin in Xining Basin. Five types of slopes, including Elymus nutans Griseb., Elymus sibiricus Linn., Agropyron trachycaulum Linn. Gaertn., Festuca arundinacea Schreb., and bare slopes are selected as the research objects. These slopes have been planted for 3 years. The study compares the effects of different herbaceous roots on the physical and mechanical properties of the soil by conducting tests of soil density and water content, and direct shear test on the soils with and without root systems. Based on these tests, a quantitative relationship between the physical and mechanical properties of different slope soils and resistivity data is established using 2D electrical resistivity tomography. The results show that: (1) Compared with the bare slope without planting, the maximum increase of soil moisture content in the upper layer (0-10 cm) of the Elymus sibiricus Linn. slope is 26.53%. The average soil density of the upper layer (0-10 cm) of the Festuca arundinacea Schreb. slope was 18.30% lower than that of the bare slope. The maximum added value of soil cohesion in the upper layer (0-10 cm) of the Elymus nutans Griseb. slope is 2.75 times that of the bare slope. (2) The resistivity characteristics of five types of slopes are affected by root distribution and slope position factors, and the resistivity value decreases with the increase of depth. The soil resistivity value of the four herbaceous slopes is larger than that of the bare slope at 0-20 cm, which is the approximately range of root distribution. (3) There are fitting equations between the physical and mechanical properties and resistivity data of five kinds of slope soils (with correlation coefficients R-2 ranging from 0.48 to 0.77), and the Pearson correlation analysis shows that the cohesion c value of the slope soil has the highest correlation with resistivity, with an R-2 value of 0.765. The results of this study demonstrate that 2D resistivity tomography technology can reflect the physical and mechanical properties of slope soil, as well as the distribution characteristics of plant roots. This provides a theoretical basis and practical guidance for effectively preventing and controlling soil erosion, shallow landslides, and other disasters in the study area and its surrounding areas.