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Cyanobacterial taxonomy is entering the genomic era, but only a few taxonomic studies have employed population genomics, which provides a framework and a multitude of tools to understand species boundaries. Phylogenomic and population genomic analyses previously suggested that several cryptic lineages emerged within the genus Laspinema. Here, we apply population genomics to define boundaries between these lineages and propose two new cryptic species, Laspinema olomoucense and L. palackyanum. Moreover, we sampled soil and puddles across Central Europe and sequenced the 16S rRNA gene and 16S‐23S ITS region of the isolated Laspinema strains. Together with database mining of 16S rRNA gene sequences, we determined that the genus Laspinema has a cosmopolitan distribution and inhabits a wide variety of habitats, including freshwater, saline water, mangroves, soil crusts, soils, puddles, and the human body. [ABSTRACT FROM AUTHOR]

Rare earth elements (REEs) are essential raw materials for modern industries but mining them has caused severe environmental issues, particularly the recovery of heavy REEs (HREEs) from ion-adsorption deposits (IADs). Very recently, an emerging technology, electrokinetic mining (EKM), has been proposed for the green and efficient recovery of REEs from IADs. However, the conduction mechanism of the weathering crust soil, which is also a prerequisite for EKM, remains unclear, making the EKM process unpredictable. Here, we systematically investigated the conductivity of weathering crust soil in the presence of light REEs (LREEs, i.e., La3+ and Sm3+) and HREEs (Er3+ and Y3+), respectively. Results suggested that the voltage was dynamically and spatially redistributed by the movement of REEs and water during EKM, and the conventional assumption of the linear distribution of voltage leads to an inaccurate description of soil voltage. We proposed an improved Archie's equation by coupling the mechanisms of liquid phase and solid-liquid interface conduction, which can predict soil conductivity more precisely. Moreover, the extended Archie's equation is able to recalculate the voltage distribution at distinct times and spaces well during EKM. More importantly, the water content in field-scale weathered-crust soils can be retrieved by the newly proposed Archie's equation, which helps optimize the leaching wells and improve the recovery rate of REE. This study focuses on the conduction mechanism of weathering crust soil, which provides a theoretical basis for better use of the EKM technology and promotes mining efficiency fundamentally. [ABSTRACT FROM AUTHOR]

The shrub and patch size of moss crusts can significantly affect plant and soil nutrients. The effects and relationships of shrubs and moss crusts on soil multifunctionality are unclear. This study aimed to understand the spatial heterogeneity of soil multifunctionality in moss crust patches and shrubs. Soil organic carbon, nutrient, and enzyme activities under moss crust patches were measured. Interestingly, the soil polyphenol oxidase (PPO) and peroxidase (POD) activities, carbon‐related soil multifunctionality index (C‐SMF), nitrogen‐related soil multifunctionality index (N‐SMF), phosphorus‐related soil multifunctionality index (P‐SMF), and soil multifunctionality index (SMF) increased with increasing patch size in moss crusts. The patch size of moss crusts had no significant effect on the C‐SMF, N‐SMF, P‐SMF, and SMF under the shrub. The soil C‐SMF, N‐SMF, P‐SMF, and SMF under shrubs were significantly higher than that in exposed areas (EAs). The soil PPO, POD, N‐SMF, P‐SMF, and SMF under dead shrubs were significantly higher than those under living shrubs and in EAs. Evaluation and composition analysis of C‐SMF, N‐SMF, and P‐SMF indicated that moss crust promotes the increase of P‐SMF, and that shrub promotes the increase of C‐SMF and N‐SMF. Moss crust patches mainly affected phosphorus functionality, increasing phosphorus cycling. Shrub promotes soil carbon and nitrogen functionality. This study elucidates the effect of moss crust patch size on soil multifunctionality influenced by shrub growth in desert ecosystems and provides further new insights into the soil processes and functions. Results are beneficial for the comprehensive utilization of fertile islands and its enhancement of beneficial ecological functions, such as maintaining soil nutrition, quality, health, and vegetation restoration, and lay a foundation for future research on nutrient absorption and utilization between mosses and shrubs. Core Ideas: The patch size effect of moss crusts is a positive in soil multifunctionality and is influenced by microhabitats.Moss crust patches mainly affected phosphorus functionality, increasing phosphorus cycling.Shrub patches mainly affected soil carbon and nitrogen functionality. [ABSTRACT FROM AUTHOR]

Microscopic green algae are severely understudied compared to their plant relatives. Algae from desert soil crusts are of special interest because they may have unique adaptations to the harsh arid habitats. Algae inhabiting gypsum substrates are especially poorly understood, and our study was the first to investigate the diversity of green algae in the gypsum soil crusts of White Sands National Park (WSNP). In addition, we characterized new algal isolates from another desert area, the Organ Mountains--Desert Peaks National Monument (OMDP), which had non-gypsiferous soils. We used a combination of light microscopy and DNA barcoding (using the rbcL and 18S genes) to classify the newly obtained algal strains. We also conducted an experiment to determine whether strain isolation could be aided by the addition of anhydrite to the growth media. We isolated 24 green algal strains, spanning 12 genera in 2 classes. There was no overlap in taxa between localities or samples. The most common taxon in the WSNP samples was Bracteacoccus minor, a common species with a near-worldwide distribution. The WSNP samples also harbored 2 genetically unique algae from the family Oocystaceae, which may represent species or genera new to science. The OMDP samples were overall more diverse than the WSNP material and contained species belonging to common soil-dwelling genera. Our growth experiment did not support our hypothesis; the growth of colonies was significantly inhibited by the addition of anhydrite to culture media, especially (and counterintuitively) in the WSNP sample. Overall, our study shows that there may be previously unknown algal species in the soil crusts of New Mexico, especially in the soils of WSNP. Additional sampling and isolation will likely reveal more algal diversity in both localities and will further enrich our knowledge of the New Mexico microflora, which to date remains largely unknown. [ABSTRACT FROM AUTHOR]

Biological soil crusts represent a rich habitat for diverse and complex eukaryotic microbial communities. A unique but extremely common habitat is the urban sidewalk and its cracks that collect detritus. While these habitats are ubiquitous across the globe, little to no work has been conducted to characterize protists found there. Amoeboid protists are major predators of bacteria and other microbial eukaryotes in these microhabitats and therefore play a substantial ecological role. From sidewalk crack soil crusts, we have isolated three naked amoebae with finely tapered subpseudopodia, and a simple life cycle consisting of a trophic amoeba and a cyst stage. Using a holistic approach including light, electron, and fluorescence microscopy as well as phylogenetics using the ribosomal small subunit rRNA gene and phylogenomics using 230 nuclear genes, we find that these amoeboid organisms fail to match any previously described eukaryote genus. However, we determined the amoebae belong to the amoebozoan lineage Variosea based on phylogenetics. The molecular analyses place our isolates in two novel genera forming a grade at the base of the variosean group Protosteliida. These three novel varioseans among two novel genera and species are herein named "Kanabo kenzan" and "Parakanabo toge." [ABSTRACT FROM AUTHOR]

Soils are threatened both in Europe and worldwide, predominantly because of human activities (e.g., unsustainable management practices in the agricultural and forestry sectors, soil contamination from the industries and soil sealing due to urbanization and building of infrastructures). Soil degradation and loss come at a substantial cost and have many repercussions on other features of the environment, such as landscapes and ecosystems. All the above prompts the question of what EU law has done to manage and rectify the situation. After the issues encountered in the context of the Proposal for a Soil Framework Directive in the past, the Green Deal and the Soil Strategy seemed to infuse new energy into the soil policy agenda and made clear that the Commission was very much ready for an ambitious step forward, in the form of a Soil Directive. However, while the proposed Directive covers important aspects of soil protection and remediation, it also falls short on several counts. [ABSTRACT FROM AUTHOR]

Seepage control is critically essential for dams, slopes, and the stability of many engineering structures, developing over many years using different methods. This study presents a novel approach for seepage control using the photopolymerization technique to form an impermeable crust at the soil surface. Effects of exposure duration (5, 10, 15, and 30 min) and light intensities (140, 550, 710, and 1000 W/m2) on the seepage control effectiveness of four different sand soils were investigated by using the photopolymerization technique. The three-point bending, permeability and acid rain simulation tests were performed to illustrate the effect of photopolymerization on the seepage control of sand soils. Furthermore, the influence of photopolymerization on the microstructure of soils was examined with the aid of SEM analysis. The results indicated that the photopolymerization technique could improve the crust strength, acid rain durability, and permeability of sand soils. The crusts at the surface layer of soils were formed after the photopolymer was applied to the sand surface and then exposed to UV light. These crusts of different soils have bending strengths and thicknesses in the range of 34.57 and 68.07 MPa, 2.13 and 6.18 mm, respectively. The increase in exposure duration and light intensity, resulted in the gradual increment of soil crust thickness. On the other hand, the increase in light intensities have more effective on the crust thickness. The formed soil crust has been provided an impermeable surface that prevents the weight loose from the surface of the soil under acid rain conditions. The SEM analysis indicated that the photopolymerized gels were homogeneously distributed between the grains in all samples, although the grain distribution of soils were different. Since the photopolymerization method has a short treatment duration and is easier to apply on the sand surface, the occurrence of the crust at the soil surface by this technique may open a new and improvable path for seepage control. The obtained results showed that the photopolymerization method is promising for repairing, restoring, and strengthening the construction materials in different engineering areas, as well as seepage control. [ABSTRACT FROM AUTHOR]

This study deals with how shifting (jhum) cultivation affects the physical, chemical, and hydraulic properties of soil-water resources in the vadose zone. This included analysis of changes in parameters such as organic matter concentration, pH, nutrient levels, and hydraulic conductivity, as well as soil texture and structure. For this, a microcatchment situated in the Aizawl District of Mizoram State in Northeast India was selected. Three sites were chosen in the catchment, each representing a different stage of cultivation viz. (1) Nonjhum land (NJL) or fallow land, (2) Newly burnt jhum land (NBJL), and (3) Cultivated jhum land (CJL). By selecting shifting (jhum) sites with similar topographical conditions, this study provides a better understanding of the effects of shifting (jhum) cultivation on the physicochemical properties of the local soil and water resources. To assess the effects of shifting (jhum) cultivation at three different stages of shifting (jhum), soil samples were collected from multiple depths, including the top surface, 5 cm, and 55 cm of the vadose zone. Water and sediment samples were also collected from three streams flowing downstream from these three shifting (jhum) sites. Findings reveal that both mean hydraulic conductivity and surface infiltration values were highest at NBJL. Furthermore, soil indices including the soil aggregate stability index (SASI), soil sealing index (SSI), and Forestier index (FI) were estimated to understand the properties of surface soils and their micronutrient and macronutrient availability. According to the SASI analysis, all soil samples from the shifting (jhum) sites exhibited a stable soil structure. The SSI results indicated that the surface soils had no risk of thrust or erosion due to shifting (jhum) practice. The FI assessment revealed that the vadose zone soils possessed abundant nutrient reserves. Soil texture in all three areas was found almost similar, with maximum percentages of medium to fine sand and the texture varying from sandy loam to loamy sand. Total organic component (TOC) (%) of surface samples were highest at CJL at 8.73% compared to 7.62% at NBJL and 7.47% at NJL. To study the seasonal variability of sediment quality, premonsoon, and monsoon comparison of all the stream sediment analysis was conducted. Macro and Micronutrients (phosphorus, potassium, calcium, magnesium, manganese, iron, sodium, and zinc) were quantified for soil and sediment samples to study the changes in their concentration at various stages of the shifting (jhum). [ABSTRACT FROM AUTHOR]

Microscopic green algae are severely understudied compared to their plant relatives. Algae from desert soil crusts are of special interest because they may have unique adaptations to the harsh arid habitats. Algae inhabiting gypsum substrates are especially poorly understood, and our study was the first to investigate the diversity of green algae in the gypsum soil crusts of White Sands National Park (WSNP). In addition, we characterized new algal isolates from another desert area, the Organ Mountains–Desert Peaks National Monument (OMDP), which had non-gypsiferous soils. We used a combination of light microscopy and DNA barcoding (using the rbcL and 18S genes) to classify the newly obtained algal strains. We also conducted an experiment to determine whether strain isolation could be aided by the addition of anhydrite to the growth media. We isolated 24 green algal strains, spanning 12 genera in 2 classes. There was no overlap in taxa between localities or samples. The most common taxon in the WSNP samples was Bracteacoccus minor, a common species with a near-worldwide distribution. The WSNP samples also harbored 2 genetically unique algae from the family Oocystaceae, which may represent species or genera new to science. The OMDP samples were overall more diverse than the WSNP material and contained species belonging to common soil-dwelling genera. Our growth experiment did not support our hypothesis; the growth of colonies was significantly inhibited by the addition of anhydrite to culture media, especially (and counterintuitively) in the WSNP sample. Overall, our study shows that there may be previously unknown algal species in the soil crusts of New Mexico, especially in the soils of WSNP. Additional sampling and isolation will likely reveal more algal diversity in both localities and will further enrich our knowledge of the New Mexico microflora, which to date remains largely unknown. [ABSTRACT FROM AUTHOR]

In recent decades, agricultural sustainability has been negatively affected by the structural degradation of soils resulting from excessive land use. In this research, the impact of different irrigation methods applied for five years in a region experiencing crusting issues on the soil's physical quality was investigated. Soil samples were taken from a region where wheat is grown and four different irrigation systems [Natural rainfall (NR), linear pivot irrigation (LPI), subsurface drip irrigation (SDI), and sprinkler irrigation (SI)] are employed, at depths of 0-20 cm, from both degraded and undegraded soils. The soil's mean weight diameter (MWD), water-resistant aggregates (WRA), saturation level (Ts), field capacity (FC), wilting point, available water content (AWC), aeration capacity, modulus of rupture, plastic limit (PL), liquid limit (LL), and plasticity index (PI) were determined. The soil's WRA were found to be the lowest at 7.76% in the NR, but this result increased by 150.64% to 19.45% in the SDI. The MWD values of the soils in the NR system were found to be 0.178 mm and it has been found to increase in the SDI system, reaching 0.467 mm. In the SDI system, the highest values were obtained for Ts, FC, and AWC. While the modulus of rupture was found to be 151.56 kPA in the NR, it was found 154.4, 44.78 and 154.2 kPA in the LPI, SDI and SI areas, respectively. The PL, LL, and PI values of the soils were not affected by different irrigation systems, and values were determined as 44.57%, 21.14%, and 23.44%, on average respectively. In this direction, the necessity of monitoring the results of soil aggregate stability and water characteristics for many years and examining them in different soil types has emerged. In addition, it has been suggested that the possible effects of irrigation systems should be considered for the sustainable use of lands. [ABSTRACT FROM AUTHOR]

In order to address the problems of soil crusting and the lack of soil fertility produced by long-term planting of tobacco, an operation device integrated the functions of deep loosening, fertilizer application, and riding was proposed in this study. The agronomic requirements of tobacco planting and the ecological benefits of organic fertilizers and other advantages were considered during the design of the device. The device was consisted of the frame, deep loosening fertilizer shovel, and ridging part. ANSYS software was used to establish the finite element model of the frame and deep loosening fertilizer shovel, and the modal simulation experiment was conducted. Results show that, under the torsion and braking interaction, the stress change of the Frame is not obvious, and the stress of the shovel tip is mainly concentrated on the combination of shovel handle and shovel body, with the stress change of other areas being insignificant. The modal analysis of the Frame shows that its resonance frequency is 61.138 Hz, and the error rate between the modal simulation and the modal test is less than 10%, which verified the feasibility of the structural design. The results of this study provide technical references for the structural design of a device for improving deep soil characteristics. [ABSTRACT FROM AUTHOR]

Wind erosion plays an essential role in the production of sediment for dust storms and occurs when strong and continuous wind interacts with dry, fine-grained and loose soil. Identifying dust production centers is the first step in prioritizing different areas for executive operations to reduce dust and determine its control methods. Jazmurian area is one of the areas where the intensity and frequency of dust events have increased in recent years and caused a lot of damage. The purpose of this research is to determine the areas prone to dust production and sensitive to wind erosion using the ILSWE model in the Jazmurian wetland basin. This model is based on five effective factors of climate erosivity, soil erodibility, soil crust, vegetation cover, and surface roughness. Maps of temperature, precipitation, wind speed, percentage of sand, silt, clay, calcium carbonate, EVI and land use were used to calculate these factors. After calculating each factor, ILSWE index was calculated by multiplying them. Finally, sensitive areas were identified by classifying this index in Arc GIS software. The ILSWE classification map showed that 46.72% of the studied area is in very low sensitivity class, 16.56% in low class, 13.67% in medium class, 12.41% in severe class and 10.64% in class Very severe sensitive to wind erosion. Severe and very severe sensitivity class was considered as the center of dust generation. The results showed that the southern (wetland area and its surroundings), west, southwest, east and southeast areas of the Jazmurian wetland basin are prone to dust production and wind erosion. These areas are mostly located in areas without vegetation (barren areas), salt marshes and sand dunes; which shows the importance of vegetation in reducing producing dust. On the other hand, the topography, the presence of wind and the characteristics of the soil in these areas help to produce dust. In general, the results of this research showed that the ILSWE model has a suitable efficiency for determining areas prone to wind erosion and dust production. [ABSTRACT FROM AUTHOR]

Desert algae are important components of the desert soil crust and play an essential role in desert soil ecosystem development. Owing to their special habitat, desert algae are often exposed to harsh environments, among which drought represents the most common stress. Green algae are considered to have drought tolerance potential; however, only a few studies have investigated this. In this study, we selected the green alga Chlorella sp., which was isolated from desert soil, and studied its physiological response to polyethylene glycol (PEG) 6000‐induced drought stress. The results showed that drought stress can affect the photosynthetic efficiency of Chlorella sp., reduce its water retention ability, and destroy its ultrastructure. However, Chlorella sp. can cope with drought stress through a series of physiological regulatory strategies. Protective strategies include quick recovery of photosynthetic efficiency and increased chlorophyll content. In addition, induced synthesis of soluble proteins, lipids, and extracellular polysaccharide (EPS), and accumulation of osmotic regulatory substances, such as sucrose and trehalose, also contribute to improving drought tolerance in Chlorella sp. This study provides insights into the physiological responses of Chlorella sp. to drought stress, which may be valuable for understanding the underlying drought adaptation mechanisms of desert green algae. [ABSTRACT FROM AUTHOR]

Decades of intense tillage have created the problem of surface sealing in loam soils across the Mid‐South United States and beyond. These soils exhibit low organic matter, poor aggregate stability, and ultimately low infiltration rates that decrease rainfed crop productivity and increase irrigation water demand. This research quantified the effects of soil management practices on rainfed maize (Zea mays L.) yield, furrow water infiltration, and soil moisture in Commerce very fine sandy loam and silt loam near Stoneville, MS. The six treatments included conventional tillage (CT), cereal rye (CR; Secale cereale L.), furrow diking (FD), no‐till (NT), polyacrylamide (PAM), and subsoiling (SS). No other treatment achieved a significantly higher maize grain yield than the CT control treatment in both years consistently. Single‐ring infiltrometer results indicated no significant differences among CT, CR, PAM, and SS in 2022 and between CT and NT in 2021. Neutron attenuation found that total soil water within the top 1 m was not significantly different among CT, FD, and SS on any of the eight measurement dates throughout the 2022 maize reproductive period. However, soil moisture was numerically lower for FD in the late reproductive stages. These findings suggest that environmental factors and other agronomic operations may counteract conservation practices, limiting their effectiveness at reducing irrigation requirements to mitigate groundwater depletion in the Mississippi River Valley Alluvial Aquifer. Core Ideas: None of the five conservation practices consistently surpassed conventional tillage in rainfed maize yield.The cereal rye, no‐till, polyacrylamide, and subsoiling treatments did not accelerate furrow water infiltration.The furrow diking and subsoiling treatments did not increase total soil water within the top 1 m.Better timing and methods of conservation intervention are needed to enhance Mid‐Southern US water sustainability. [ABSTRACT FROM AUTHOR]

A one-g shake table experiment was performed to reveal the failure mechanism of the pile group in sloping liquefiable soils with crusts. The results show that the shallow saturated sand exhibits the alternate behavior of dilatancy and shrinkage, which induces high-frequency peak acceleration. In addition, larger PGA tends to transfer vulnerable positions of the pile in the liquefiable layer from the shallow layer to the interface. Moreover, the pile group effect mainly manifested in piles at the bottom of saturated sand and pile-head during strong earthquakes. [ABSTRACT FROM AUTHOR]

Two large-scale shake table experiments were conducted to study the seismic pile group–bridge soil system failure mechanisms and examine the role of soil crust in lateral spreading caused by liquefaction. Pile group–bridge systems were supported by two different ground profiles, inclined liquefiable soils with and without soil crusts. The test results are discussed in terms of soil acceleration, pore pressure ratio, and displacement response. In addition, the pile seismic failure mechanisms are depicted according to the acquired date, and the effects of kinematic and inertial interaction on the curvature of pile and pier are evaluated. It was found that during weak earthquakes, the crust did not have an apparent influence on the system response. However, during strong earthquakes, the soil bed without crust experienced larger lateral permanent displacement because the shallow soil showed dilatant response and triggered spikes in acceleration. Meanwhile, the soil bed with crust restrained the lateral bridge displacement. In addition, the lateral spreading caused by liquefaction transferred the damaged position of the pile group–bridge system from the pier bottom to the pile at the bottom of liquefied soil, while the crust shifted the damaged position from the bottom of the liquefiable soil to the top of pile. The results also revealed that the crust weakened the kinematic interaction on curvature at the pile head but enhanced the inertia effect during the strong earthquake, while the opposite was true for ground without crust; the kinematic interaction was stronger, and the inertia interaction was diminished. [ABSTRACT FROM AUTHOR]

This work seeks to answer the question as to whether the legal orders of Poland and Germany provide an effective framework for energy-efficient and climate-resilient urban space management. To this end, it verifies what similarities and differences exist between certain areas and whether they need reform. The starting point is the belief that legal instruments for environmentally friendly space management are a cross-border issue. Comparative studies are important because effective environmental protection knows no borders, and a lower level of protection in one country or geographic region can affect neighbouring countries and regions. The analysis of legal norms affecting such issues as passive energy construction; prevention of soil sealing and adequate ventilation; reduction of CO2 emissions; promotion of green areas; proper water management; reduction of so-called "grey energy" associated with new construction; the compact city; and a reduction of light pollution has enabled us to synthesise findings into specific conclusions and to propose postulates and directions for further research. However, this does not change the overall assessment that the legal systems of Poland and Germany enable environmentally friendly space management at a similar level, while at the same time, certain additions to the regulations and a further discussion of possible improvements are most welcome and needed. [ABSTRACT FROM AUTHOR]

Climate change has an effect on ecosystems and people all around the globe and causes land degradation. A long‐term decline in biological output, loss of ecological integrity, and a fall in the economic worth of the land are all signs of "land degradation", a downbeat trend in land condition. In the red lateritic zone of the tropical area, where "climate change" and "land degradation" are related, they impact one another. On the other hand, due to the emissions of greenhouse gases (GHGs), which slow the rate of carbon absorption, and the extent of various existing land degradation processes, which are worsened in pace and magnitude by "climate change". The world's expanding population poses a challenge to supplying the rising demand for food in recent decades. The need for additional land for farming, feed, and other forms of production is fuelled by poverty and the destruction of the environment. In tropical regions, "soil erosion" caused by "water and wind, salinization and alkalinity, acidity, losses of organic carbon, nutrient imbalance, pollution/contamination by toxic substances, and soil sealing and capping" all call for immediate action to stop the land degradation process and sustainably restore productivity for environmental security and food security for the world's expanding population. After fulfilling the requirement systematic knowledge about soil, scientific use of natural resources (water, land, minerals, vegetation, air and biodiversity) will present a healthy planet with a healthy ecological system for future generations. [ABSTRACT FROM AUTHOR]

Simple Summary: In sacred forest groves, biological soil crusts comprise cyanobacteria covering the surface of the soil. Extracellular polysaccharides (EPSs) from the biological soil crust enhance the availability of nutrients and water. This study aimed to extract and characterize EPSs from the biological soil crust, in addition to gaining insights into their potential as a bioflocculant and antioxidant. The cyanobacteria diversity in the biological crust and their phylogenetic relationships in response to the forest ecosystem are addressed. The biochemical analysis of EPSs revealed an abundance of carbohydrates and proteins. FTIR and LC-MS profiles of EPSs revealed various functional groups which confer antioxidant and flocculation activity. EPS-releasing biological soil crust acts as a biofertilizer in sacred forests by contributing carbon, nitrogen, soil aggregation, and moisture retention. Exopolysaccharide-producing cyanobacterial strains in biological soil crusts are described, in addition to their chemical properties and antioxidant and flocculation activities. The EPSs from Pudukkottai blackish biological soil crusts (PBBSCs) showed significant amounts of total soluble proteins (0.1687 mg/mL) and carbohydrates (0.8056 mg/mL) compared with the Ariyalur blackish biological soil crusts (ABBSCs). LC-MS analysis of the cyanobacterial polysaccharides revealed the presence of natural sugars such as ribose and glucose/mannose, and uronic acids. The FTIR spectrum showed specific peak for OH and –NH stretching, C–H stretching, and carboxylic acids as the dominant groups in EPS. The in vitro DPPH assay of EPSs from PBBSCs showed 74.3% scavenging activity. Furthermore, the reducing power was determined to be 0.59 ata 500 mg/mL concentration, respectively. The extracted EPSs from the biological soil crust flocculated Kaolin clay suspension maximum at 500 mg/mL. Consequently, the cyanobacterial strain and exopolysaccharide characterization from the sacred forest's biological soil crust were analyzed for their bioactive potential, bio-crust diversity, and distribution. [ABSTRACT FROM AUTHOR]

Biological soil crust can effectively prevent wind erosion of sand and soil, which is of great significance to ecological restoration in desert areas. There have been few studies that have screened different planting patterns by analyzing biological crust properties. In this study, high-throughput sequencing was used to analyze the bacterial 16S rRNA community structure of biologically crusted soil in sandy bare land (CK), planting corn soil crust (CB), planting potato soil crust (TB) and planting alfalfa soil crust (AB), and nutrient profiles of each soil type were also analyzed. The results showed that soil nutrient content was significantly increased by the biological layer, and the organic matter, available phosphorus, and available potassium contents were significantly increased. In terms of bacterial communities, the TB treatment had more endemic genera (100). The top 10 phyla in terms of relative abundance accounted for around 95% of the total community, with Actinobacteria being the highest. The community structure of CB and AB was similar, and the diversity and richness indices of CB were significantly increased compared to those of CK. The available phosphorus and total nitrogen were found to be the main factors affecting bacterial community structure. The dominant role of Actinobacteria was mainly determined by pH. Overall, the results show that corn planting could be most helpful in the early restoration period of sandy land. [ABSTRACT FROM AUTHOR]

In recent years, the dust phenomenon has become one of the most important environmental challenges throughout the world, and one of its negative effects is on the agriculture sector. The aim of this research is first to determine dust emission sources in Alborz Province and then to estimate the willingness to pay (WTP) for reducing the effects of dust on the agriculture of dust emission sources and their surrounding areas. The Index of Land Susceptibility to Wind Erosion (ILSWE) was used to determine dust emission sources. ILSWE consisted of the combination of 5 effective factors in wind erosion, namely climate erosivity, soil erodibility, soil crust, vegetation cover, and surface roughness. In the next step, according to the produced map of dust emission sources, the affected rural districts were identified, and then using the contingent valuation method (CVM), individuals' WTP for preventing and reducing the negative impacts of the dust phenomenon on the agriculture was calculated by 400 questionnaires. According to the results, the classification map of ILSWE indicated that while classifying the areas in terms of their sensitivity to wind erosion 7.8% of the study area was placed in the very high sensitivity class. This class was considered the center of dust production, which was located chiefly in the southern parts of Alborz Province. Using the CVM method, the expected value rate and the WTP were calculated as 1654231 Rials (approximately $ 5.5). According to the population of the affected area, the total value of protecting the agricultural products against dust phenomenon is 27433766904 Rials ($91445.89) annually. [ABSTRACT FROM AUTHOR]

Germany aims to reduce soil sealing to under 30 hectares per day by 2030 to address negative environmental impacts from the expansion of impervious surfaces. As cities adapt to climate change, spatially explicit very high-resolution information about the distribution of impervious surfaces is becoming increasingly important for urban planning and decision-making. This study proposes a method for mapping impervious surfaces in Google Earth Engine (GEE) using a data fusion approach of 0.9 m colour-infrared true orthophotos, digital elevation models, and vector data. We conducted a pixel-based random forest (RF) classification utilizing spectral indices, Grey-Level Co-occurrence Matrix texture features, and topographic features. Impervious surfaces were mapped with 0.9 m precision resulting in an Overall Accuracy of 92.31% and Kappa-Coefficient of 84.62%. To address challenges posed by high-resolution imagery, we superimposed the RF classification results with land use data from Germany's Authoritative Real Estate Cadastre Information System (ALKIS). The results show that 25.26% of the city of Wuppertal is covered by impervious surfaces coinciding with a government-funded study from 2020 based on Sentinel-2 Copernicus data that defined a proportion of 25.22% as built-up area. This demonstrates the effectiveness of our method for semi-automated mapping of impervious surfaces in GEE to support urban planning on a local to regional scale. [ABSTRACT FROM AUTHOR]

Dry salt lakes are widely distributed in semi-arid regions. Dry lake beds have been found to have a greater capacity to release dust. However, the particle size characteristics of dry lakebed soils have rarely been studied. To reveal the soil grain size characteristics, we used surface and subsurface soil from dry lake beds in semi-arid regions with different soil crusts as the object of study. We used particle size parameters and class-standard deviation methods to study the particle size variation patterns and the degree of variability. The results show that the dry lake was mainly composed of clay (1.36%-43.96%) and silt (5.5%-67.94%) particles. Soil particle characteristics show the Mean size (Mz) of (0.65-8.89 f), poorly sorted (0.79-3.38 f) and a clear linear relationship between dry lake bed skewness and sorting. There is a high variability between soil particle size fractions across the lake bed, with soil crusts and soil moisture protecting the loss of subsurface soil particles, hence the differences between surface and subsurface soil particles. However, the destruction of the soil crust and the evaporation of soil moisture accelerates the wind erosion of the subsurface soil particles. In the dry lake area, vegetation construction has promoted the accumulation of sand content (73.28% -93.08%). We found that the fractions 0.19-9.15 µm, 9.15-36.99 µm, 36.99-366.93 µm, and 366.93-1214.72 µm are susceptible to respond to environmental changes and contribute to dust storms. Therefore, local governments should treat and manage dried-up lakes to reduce the impact of salt dust on the ecosystem. [ABSTRACT FROM AUTHOR]

The paper proposes a new soil evaluation system using the principle of the Saaty method. The Saaty method has been modified and named Soil Assessment System (SAS). Significance weights are assigned to individual soil characteristics (indicators). This provides a more detailed differentiation of the significance of the indicator on soil quality and a more accurate assessment, especially in marginal cases where the assessment by the methods used so far has not been fully conclusive. In addition to physico-chemical properties, other criteria are taken into account to assess not only productional but also non-productional functions. The possibility of using indicators referring to a broader context (e.g., soil sealing value) is also important, thus enabling a comprehensive assessment of the quality of the land. This results in points for individual sampling locations. Soils are categorized according to the number of points and results are shown on maps. [ABSTRACT FROM AUTHOR]

It is necessary to recognize soils in their singularity and with their multiplicity of important ecosystem functions for humans as well as for animals and plants that soils will be recognized as important resource that need to be protected from degradation and disturbance. Soils in the intra- and peri-urban space are threaten to an extremely high extend by soil sealing and contamination as well as disturbance of the natural soil profile, which affects soil quality and soil functioning. Knowledge about different soil qualities in a certain area and about already degraded or disturbed sites can help to protect intact soils and to use soils according to their potential as a plant site or production field. Soils with a high yield potential and with a high rating should not be sealed when degraded sites are available as well. The meaning of natural soils when it comes to intra-urban agriculture will be presumably low as projects like Vertical Farming or Indoor Farming will be realized by using substrates instead of soils. Nevertheless, it is important to develop a high awareness in the community for the meaning and biodiversity of soils as agricultural soils will be the basis for future food and feed production as well as production of renewable resources. Last but not least, soils are an important part in combating high CO2 in the atmosphere with their potentially high carbon stocks. [ABSTRACT FROM AUTHOR]

Urbanization has had a major impact on runoff process, which is not fully understood. In this study, a plot‐scale rainfall‐runoff simulation experiment was conducted in an experimental field to evaluate the effects of imperviousness and its connectivity on surface runoff. A total of 11 underlying surface scenarios with different impervious area and two imperviousness connectivity conditions were designed. For each scenario, two rainfall intensities and two initial soil moistures were applied. The results show that the relationship between the surface runoff coefficient and the impervious area under fixed imperviousness connectivity, rainfall intensity, and initial soil moisture represents a strong linear trend. With high antecedent soil moisture, imperviousness arranging in disconnected pattern can lead to initially lower but later higher outflow rate compared to imperviousness arranging in connected pattern. The sensitivity of the runoff coefficient to impervious area, which represents increased runoff coefficient per unit impervious area, is negatively related to the rainfall intensity as well as the initial soil moisture but positively related to the imperviousness connectivity. These results indicate that the impacts of the impervious surface on runoff are not only related to its connectivity, but also the original soil condition before sealing: the higher infiltration capacity of the original soil, the greater hydrological impacts caused by soil sealing. [ABSTRACT FROM AUTHOR]

Consistent and optimized territorial planning, imply the use of numerous variables aimed at improving life quality and reduction of environmental impacts. The resilience of the territory to climate change threats is strongly linked to its progressive transformation. This fact is extremely evident in coastal systems, which are intrinsically fragile systems due to their high environmental value and strong anthropogenic pressure. The existing tools and techniques provide to outline future transformation effects through the scenarios analysis. This work has the objective to evaluate the effects of land use changes in the territory of the Abruzzo coast. The conversion from natural soils to artificial uses has a significant impact on several ecosystem services. The regulation services considered in this work are flood regulation, carbon storage and sequestration, and habitat for biodiversity. The first is directly connected to soil sealing which determines a reduction of water infiltration with the consequent overloading of the existing sewerage systems. The quantitative evaluation is made using the concept of surface runoff coefficient. Instead, the estimation of the last two ecosystem services has been made using InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) models, specifically the Carbon Storage and Sequestration model and the Habitat Quality model. The results show that Land Use Changes (2012–2018) caused a potential increase of 10% in runoff and an annual Carbon Sequestration loss estimated at about €820,000. [ABSTRACT FROM AUTHOR]

Wild bees are declining, mainly due to the expansion of urban habitats that have led to land-use changes. Effects of urbanization on wild bee communities are still unclear, as shown by contrasting reports on their species and functional diversities in urban habitats. To address this current controversy, we built a large dataset, merging 16 surveys carried out in 3 countries of Western Europe during the past decades, and tested whether urbanization influences local wild bee taxonomic and functional community composition. These surveys encompassed a range of urbanization levels, that were quantified using two complementary metrics: the proportion of impervious surfaces and the human population density. Urban expansion, when measured as a proportion of impervious surfaces, but not as human population density, was significantly and negatively correlated with wild bee community species richness. Taxonomic dissimilarity of the bee community was independent of both urbanization metrics. However, occurrence rates of functional traits revealed significant differences between lightly and highly urbanized communities, for both urbanization metrics. With higher human population density, probabilities of occurrence of above-ground nesters, generalist and small species increased. With higher soil sealing, probabilities of occurrence of above-ground nesters, generalists and social bees increased as well. Overall, these results, based on a large European dataset, suggest that urbanization can have negative impacts on wild bee diversity. They further identify some traits favored in urban environments, showing that several wild bee species can thrive in cities. [ABSTRACT FROM AUTHOR]

Geochemical background is the basis of anomaly evaluation in mineral exploration and environmental investigation. However, the background value obtained from secondary media is inevitably affected by weathering, transportation, and sorting, which leads to secondary depletion or enrichment of chemical elements. This problem can be avoided by the geochemical mapping of the exposed crust. In this paper, more than 38,000 samples of rocks data were collected, and an original method was presented for the first time to produce the cobalt geochemical map of exposed crust across the whole of China. Using a geological map grid of 1:200,000 as the basic calculation unit, the area and content of rock types in each unit were calculated, and then the grid was assigned using the area-weighted average method. Based on this, an geochemical contour map was drawn in ArcGIS. The results show that the median of the exposed crust is 9.74 mg/kg, which is lower than that of the whole crust and soils. This value is explained by the vertical heterogeneity of the crust and the secondary enrichment, respectively. Co anomalies and anomalous centers of exposed crust are distributed in southwest, north, and northwest China, where they are primarily related to Permian Emeishan Large Igneous Province (ELIP), Pacific plate, and the big mantle wedge (BMW), Archean metamorphic basic rocks, and ophiolite belts. [ABSTRACT FROM AUTHOR]

Environmental pollution is one of the main factors that significantly affect biological systems and human health. Soil pollution with heavy metals is an increasingly pressing problem worldwide. In general, heavy metals are stable and do not decompose, unlike other organic pollutants. The quantity of them is natural components of soil crust, the remaining come from human activities, which may result from the extensive use of sewage. In the present study, a methodology aimed at simultaneous quantification of 16 heavy elements in soil of 3 different regions was developed. The concentration of 16 soil heavy metals (Se, Cd, V, Be, As, Mn, Co, Zn, Fe, Cr, Pb, Ni, Cu, Mo, Hg, and Ti) was measured in 11 sampling along Riyadh, Qassim, and Medina, Kingdom of Saudi Arabia from 3 sites soil treated with sewage water. These chemical minerals were identified in the samples using an ICPE-9000 spectrometer. The assessment of heavy metal contamination was derived using enrichment factors (EF), the pollution load index (PLI), and geoaccumulation index (Igeo). This study revealed that the soil is predominantly polluted by Cd, As, and Mo of Riyadh and Medina and As, Mo, and Cd of Qassim region at site B and site C, respectively. As recorded, the highest concentration value of 5000 mg/kg for Fe at site (B) followed by Cu. The Igeo value of Cd is 1.1520 in Medina region. The Igeo value of Se is 3.2395 in Medina region, while its cumulative geographical index decreased in the regions of Riyadh and Qassim, which amounted to 2.6114 and 2.1699, respectively. The Igeo values of the rest of the minerals in the three regions studied indicated that the soil is unpolluted, while it was slightly to moderately polluted for both Mo and Hg in most regions studied. The minerals in the soil at all sites studied were less than the general average concentration. With the exception of mercury, molybdenum, arsenic, cadmium, and selenium, whose concentration exceeded the permissible and recommended limits. The increasing order of concentration of minerals was Be < V < Cd < Hg < Mo < Co < Zn < Pb < Cr < Se < As < Ni < Ti < Mn < Cu < Fe at all sites, respectively. [ABSTRACT FROM AUTHOR]

Agronomic factors can affect mycotoxin contamination of maize, one of the most produced cereals. Maize is usually harvested at 18% moisture, but it is not microbiologically stable until it reaches 14% moisture at the drying plants. We studied how three agronomic factors (crop diversification, tillage system and nitrogen fertilization rate) can affect fungal and mycotoxin contamination (deoxynivalenol and fumonisins B1 and B2) in maize at harvest. In addition, changes in maize during a simulated harvest-till-drying period were studied. DON content at harvest was higher for maize under intensive tillage than using direct drilling (2695 and 474 μg kg−1, respectively). We found two reasons for this: (i) soil crusting in intensive tillage plots caused the formation of pools of water that created high air humidity conditions, favouring the development of DON-producing moulds; (ii) the population of Lumbricus terrestris, an earthworm that would indirectly minimize fungal infection and mycotoxin production on maize kernels, is reduced in intensive tillage plots. Therefore, direct drilling is a better approach than intensive tillage for both preventing DON contamination and preserving soil quality. Concerning the simulated harvest-till-drying period, DON significantly increased between storage days 0 and 5. Water activity dropped on the 4th day, below the threshold for DON production (around 0.91). From our perspective, this study constitutes a step forward towards understanding the relationships between agronomic factors and mycotoxin contamination in maize, and towards improving food safety. [ABSTRACT FROM AUTHOR]

The Copernicus high-resolution layer imperviousness density (HRL IMD) for 2018 is a 10 m resolution raster showing the degree of soil sealing across Europe. The imperviousness gradation (0–100%) per pixel is determined by semi-automated classification of remote sensing imagery and based on calibrated NDVI. The product was assessed using a within-pixel point sample of ground truth examined on very high-resolution orthophoto for the section of the product covering Norway. The results show a high overall accuracy, due to the large tracts of natural surfaces correctly portrayed as permeable (0% imperviousness). The total sealed area in Norway is underestimated by approximately 33% by HRL IMD. Point sampling within pixels was found to be suitable for verification of remote sensing products where the measurement is a binomial proportion (e.g., soil sealing or canopy coverage) when high-resolution aerial imagery is available as ground truth. The method is, however, vulnerable to inaccuracies due to geometrical inconsistency, sampling errors and mistaken interpretation of the ground truth. Systematic sampling inside each pixel is easy to work with and is known to produce more accurate estimates than a simple random sample when spatial autocorrelation is present, but this improvement goes unnoticed unless the status and location of each sample point inside the pixel is recorded and an appropriate method is applied to estimate the within-pixel sampling accuracy. [ABSTRACT FROM AUTHOR]

The soils of urban areas were belatedly discovered as a research subject, becoming popular for study in the 1970s. With the growth of cities, there were increased requirements for urban soil information to assure the urban quality of life. Thus, the WG Urban Soils (AKS [Arbeitskreis Stadtboeden], today AGUB) within the German Soil Science Society (DBG) was established in 1987. This paper outlines the national and international achievements of AKS/AGUB and the initiated international urban soil network. Particular attention is given to soil mapping and research in Germany. The foundation of AKS/AGUB initiated a high scientific response on the new research field of urban soils. A soil mapping instruction was established. According to the German concept of soil unit "soil form" from the substrate and soil formation, much attention was given to soil material of natural and technic origin, as well as structure and profile composition. The focus of soil formation is on the young age, the effect of artificial landscape construction, and the speed of soil development. For surveying areas of high soil diversity, conceptual maps were developed. A great number of cities were mapped. As in Germany, urban soils were included in several national soil classification systems. Those of Germany, the United States, Russia, France, and the international World Reference Base for Soil Resources (WRB) are compared. A great number of tasks of urban administration concern soil problems, such as pollution, soil sealing, urban greening, stormwater infiltration, heating, dust, and carbon sequestration, so soils were relevant in city government work. Internationally, the WG SUITMA of International Union of Soil Science and the US WG INCOMANTH were dedicated to urban soils. The AKS/AGUB could contribute to the European Commission with concepts of soil functions and soil evaluation and the introduction of Technosols to the WRB. Important future aspects will be the competition of intense rising soil consumption by building activities, and the availability and quality of soils for a sustainable urban life. [ABSTRACT FROM AUTHOR]

Fires can alter the hydraulic properties of burned soils through the consumption of organic matter on the ground surface. This study examined the effects of rainfall on the presence of soil pore clogging with varying ash layer thickness using laboratory rainfall simulator experiments. The image analysis with resin impregnation showed that rainfall impact caused plugging of soil pores at 22.2% with soil particles and 14.3% with ash particles on near surface soils (0–5 mm below). High rainfall intensities enhanced soil pore clogging by ash particles, particularly at shallow soil depths (0–10 mm). Ash deposits on the soil surface increased the water-absorbing capacity of ash-covered soils compared with that of bare soils. The rainfall simulation experiments also showed that ash cover led to a reduction in soil hydraulic conductivity, owing to the combined effects of surface crust formation and soil pore clogging. The complementary effects of soil pore clogging and water absorption by ash cover could hamper the accurate understanding of the soil hydrologic processes in burned soils. [ABSTRACT FROM AUTHOR]

Soil crusting is a common problem that affects crop emergence and growth worldwide across different soil and climate conditions. This study aimed to investigate the impact of various tillage methods on soil crust formation and assess the effectiveness of soil crust breakers in enhancing cotton seedling emergence. The research was conducted on Silty-Loam soil, examining the impact of four tillage methods: Method A, a conventional tillage approach employing a moldboard plow, disc harrow, and roller; Method B, a conservation tillage method involving a chisel plow, disc harrow and roller; Method C, another conventional tillage method utilizing a chisel plow, powered rotary tiller, and roller; and Method D, another conservation tillage approach utilizing a disc harrow and roller. Two types of crust breakers, a rolling type, and a skid blade type, were tested. The results showed significant variations in soil crusting hardness among the tillage methods, with conservation tillage methods B and D being the most effective in reducing penetration resistance. The post-crust-breaking penetration resistance declined, decreasing from 305 to 408 kPa in the control plots to 60–93 kPa in the treated plots. Breaking the soil crust with the crust breakers considerably reduced penetration resistance, improving soil conditions for seedling emergence and root growth. Seedling emergence was significantly influenced by tillage methods, with conservation tillage methods B and D promoting the highest emergence rates. The mean percent emergence of subplots (with crust breaker applications) was 77.8% when the chisel plow, disc harrow, and roller were applied (Method B) and 78.2% when the disc harrow and roller were applied for tillage (Method D). The percentage of emerged cotton seedlings in the control plots ranged from 51.1% to 86.2%, with the tillage method order of C < A < B < D. However, the soil crust-breaking treatments were effective in increasing the percentage of emerged cotton seedlings for all tillage methods. The rolling-type crust breaker was particularly effective in breaking the crust and enhancing emergence for methods A and C. It increased the emergence percentage by 27.1% for method A and 34% for method C. The study also revealed that the hardness of the soil crust significantly affected emergence time and emergence rate index. Harder soil crusts resulted in longer mean emergence times and lower emergence rate indices. The conventional tillage method involved a chisel plow, powered rotary tiller, and roller, contributing to a harder soil crust with the highest penetration resistance recorded at 408 kPa for the control plot (without soil crust breaking). This resulted in the longest emergence time of 9.8 days and the lowest emergence rate index of 0.38 seedlings/m·day. However, after the soil crust-breaking treatment, the differences in emergence time and emergence rate indices among different tillage methods and crust breakers became statistically insignificant (P>0.05). • Impact of tillage methods on soil crust formation. • Effectiveness of soil crust breakers on cotton seedling emergence. • Conservation tillage methods for reduced penetration resistance. • Role of rolling-type crust breaker in enhancing emergence of cotton seedlings. • Mitigation of emergence challenges across tillage methods with soil crust breakers. [ABSTRACT FROM AUTHOR]

The bearing capacity of unsaturated soft soil foundations is affected by natural or artificial hard crust, due to the stress diffusion and closure effect. Based on the triple-shear unified solution of shear strength for unsaturated soil, the analytical solutions of critical edge load and critical load of unsaturated soft soil with hard crust are derived with the consideration of the lateral pressure coefficient K 0 ≠ 1. The formulas are degraded and compared. Meanwhile, the influences of stress diffusion, increased load, matric suction, intermediate principal, and lateral pressure coefficient are conducted on the bearing capacity of unsaturated soft soil foundations with hard crust. The results show that the critical edge load and critical load increased, and the stress diffusion coefficient decreased with the increase of the ratio of elastic modulus between hard crust and soft soil. The bearing capacity of soft soil foundation increased with the consideration of the stress diffusion and closure effect of hard crust. The effect of matric suction is remarkable, and the critical edge load and critical load linearly increase with the increase of low matric suction and variate with the dual influence of high matric suction. The bearing capacity of unsaturated soft soil foundation is obviously higher than that of saturated soil. The critical edge load and critical load increased with the increase of intermediate principal stress and lateral pressure coefficient. The triple-shear unified solution for bearing capacity of unsaturated soft soil foundation with hard crust contains different solutions under various working conditions, which has important theoretical significance and widely engineering application. [ABSTRACT FROM AUTHOR]

Environmental hazards affect people from different income groups and migration backgrounds on different levels. The research on environmental inequalities and environmental justice has proposed several theories to explain such inequities; still, it remains unclear which of these theories applies to the German societal context. This research investigates whether individual-level income differences between Germans and migrants account for objectively measured exposure to the environmental goods and bads of land use, specifically soil sealing and green spaces. Marginal effects and predictions based on georeferenced survey data from the German General Social Survey reveal that Germans with higher incomes live in areas with better neighbourhood quality. Germans with lower incomes are exposed to fewer disadvantages stemming from land use, and there is no marginal difference between nonurban and urban municipalities. Spatial assimilation in high-income groups occurs; however, the difference in low-income groups can be explained by place stratification and discrimination in the housing market. While this study uses more indirect and non-hazardous measures of environmental quality – in contrast to air pollution or noise – it provides evidence that such indicators also create distributional injustices in Germany. [ABSTRACT FROM AUTHOR]

Introduction: Biological soil crusts including cyanobacteria, fungi, bacteria, actinomycetes, algae, viruses, mosses, lichens, and plants are formed on the soil surface. Cyanobacteria are key microorganisms in the formation of the biological soil crust, especially in arid and desert areas. Cyanobacteria increase carbon and nitrogen content in soil via increasing colony formation and Exopolysaccharide (EPS) production and play an important role to strengthen soil structure especially in poor soil and prevent it from eroding. Materials and Methods: In the present study, three cyanobacteria with the highest secreted carbohydrate production were selected among 19 isolates of different provinces’ soil. The amount of carbohydrate production of the selected strains was determined by using the phenolic sulfuric acid method. Then, three selected strains, with the highest amount of secreted carbohydrate were inoculated to the pot filling with poor soils. After 7 weeks of cyanobacterial inoculation, some physical and chemical alterations of the soil were measured. Furthermore, the rate of formation of the biological soil crust and the adhesiveness of the soil particles were microscopically investigated. Results: The carbohydrate content was 86.66 µg/ml for Anabaena sphaerica, 55 .91 µg/ml for Geitlerinema.sp, and 64.19 µg/ml, for Nostoc pruniforme. The results of the study also show that these three strains are capable of forming biological soil crust on the soil surface. Discussion and Conclusion: Anabaena sphaerica, due to its high growth rate, more biomass production, and more secreted carbohydrates increased soil nitrogen and carbon content, as well as better formation of biological soil crust was selected for further investigation. This strain improved some soil texture characteristics and probably it can have a positive effect on soil fertility. [ABSTRACT FROM AUTHOR]

Salinity systems are well known as extreme environmental systems that occur either naturally or by certain human activities, in arid and semiarid regions, which may harm crop production. Soil salinity identification is essential for soil management and reclamation projects. Information derived from space data acquisition systems (e.g., Landsat, ASTER) is considered as one of the most rapid techniques in mapping Salt-Affected Soil (SAfSoil). The current study tested the previously proposed salinity indices on the northern Nile Delta region, Egypt. The results indicated that most of the indices were not suitable to detect the SAfSoil in the area, due to the interaction between the bare soils, salts, and urbanization. To resolve this issue, the current work suggested a new index for detecting and monitoring the SAfSoil in the Nile Delta region. The newly proposed index takes into consideration plant health, the salt crust at the surface of the soils, as well as urbanization. It facilitates the mapping processes of SAfSoil in the area compared to any other previously proposed index. In this respect, multi-temporal Landsat-7 and 8 satellite data, acquired in 2002, 2016, and 2021, were used. The new index was prepared using the 2002 data and verified using the 2016 and 2021 data. Field measurements and data collected during 2002, 2016, and 2021 were utilized as ground truth data to assess the accuracy of the results obtained from the proposed index. The evaluation of the results indicated that the accuracy assessment for 2002, 2016, and 2021 images was 94.58, 96.08, and 95.68%, respectively. Finally, the effectiveness of using remote sensing in detecting and mapping SAfSoil is outlined. [ABSTRACT FROM AUTHOR]

The quantity and quality of soil organic matter (SOM) depending on many edaphic and environmental factors may change in response to agriculture-related practices. The SOM humification process can be supported by the application of mineral fertilizers, but in the production vineyards, such information is lacking. NPK fertilizer alters the soil quality, and therefore, the aim of this study was to: (1) assess the extent and dynamics of different NPK (control—no fertilization; 1st NPK; and 3rd NPK levels) rates to the soil with grass sward cover in a productive vineyard on changes in SOM, humic substances (HS), and soil structure, and (2) identify relationships between SOM, HS, and soil structure. Results showed that the share of humic acids in soil organic carbon decreased only in NPK1 compared to control and NPK3 treatments. The color quotient of humic substance values in NPK1 and NPK3 increased by 4 and 5%, respectively, compared to control. Over a period of 14 years, the content of soil organic carbon increased by 0.71, 0.69, and 0.53 g kg−1 year−1 in the control, NPK1, and NPK3, respectively. The content of HS increased linearly with slight differences due to NPK application. The vulnerability of the soil structure decreased due to fertilization—more at the higher NPK level. The rate of formed soil crust was decreasing in the following order: control > NPK1 > NPK3. In the control treatment, the relations between SOM, HS, and soil structure were most abundant and with the greatest significance, while with the increasing level of NPK, these relations lost their significance. [ABSTRACT FROM AUTHOR]

Cyanobacteria are an evolutionarily ancient and diverse group of microorganisms. Their genetic diversity has 
allowed them to occupy and play vital roles in a wide range of ecological niches, from desert soil crusts to tropical oceans. Owing to bioprospecting efforts and the development of new platform technologies enabling their study and manipulation, our knowledge of cyanobacterial metabolism is rapidly expanding. This review explores our current understanding of the genetic and metabolic features of cyanobacteria, from the more established cyanobacterial model strains to the newly isolated/described species, particularly the fast-growing, highly productive, and genetically amenable strains, as promising chassis for renewable biotechnology. It also discusses emerging technologies for their study and manipulation, enabling researchers to harness the astounding diversity of the cyanobacterial genomic and metabolic treasure trove towards the establishment of a sustainable bioeconomy. [ABSTRACT FROM AUTHOR]

Cyanobacteria are crucial primary producers in soil and soil crusts. However, their biodiversity in these habitats remains poorly understood, especially in the tropical and polar regions. We employed whole genome sequencing, morphology, and ecology to describe a novel cyanobacterial genus Argonema isolated from Antarctica. Extreme environments are renowned for their relatively high number of endemic species, but whether cyanobacteria are endemic or not is open to much current debate. To determine if a cyanobacterial lineage is endemic is a time consuming, elaborate, and expensive global sampling effort. Thus, we propose an approach that will help to overcome the limits of the sampling effort and better understand the global distribution of cyanobacterial clades. We employed a Sequencing Read Archive, which provides a rich source of data from thousands of environmental samples. We developed a framework for a characterization of the global distribution of any microbial species using Sequencing Read Archive. Using this approach, we found that Argonema is actually cosmopolitan in arid regions. It provides further evidence that endemic microbial taxa are likely to be much rarer than expected. [ABSTRACT FROM AUTHOR]

Cyanobacteria are crucial primary producers in soil and soil crusts. However, their biodiversity in these habitats remains poorly understood, especially in the tropical and polar regions. We employed whole genome sequencing, morphology, and ecology to describe a novel cyanobacterial genus Argonema isolated from Antarctica. Extreme environments are renowned for their relatively high number of endemic species, but whether cyanobacteria are endemic or not is open to much current debate. To determine if a cyanobacterial lineage is endemic is a time consuming, elaborate, and expensive global sampling effort. Thus, we propose an approach that will help to overcome the limits of the sampling effort and better understand the global distribution of cyanobacterial clades. We employed a Sequencing Read Archive, which provides a rich source of data from thousands of environmental samples. We developed a framework for a characterization of the global distribution of any microbial species using Sequencing Read Archive. Using this approach, we found that Argonema is actually cosmopolitan in arid regions. It provides further evidence that endemic microbial taxa are likely to be much rarer than expected. [ABSTRACT FROM AUTHOR]

• Parameters of the soil moisture and structure density significantly affect its grinding by the working bodies. • The influence of the rotor significantly affects the output of agronomic valuable aggregates. • With increasing rotor speed, there is a clear tendency to improve crumbling. The subject of the study is the parameters of the soil crumbling, depending on the rotation frequency of the rotor of the soil treatment installation under different initial parameters of moisture and density of the soil structure. Field tests of an experimental soil tillage installation with a loosen-separating device have been carried out. In order to determine the value of the soil crumbling, depending on the rotor rotation frequency of the grinding and separating device of the soil tillage installation, different mathematical models of soil crusting were obtained at different initial humidity and soil density parameters. The object of the study is the influence of the investigated factors on the soil crumbling. The effective grinding of soil with a soil cultivating installation with a wide range of initial parameters of the density of the structure and the moisture content of the surface layer of soil was revealed, increasing the rotor speed increased with adverse parameters of density and soil moisture. In variants with increased parameters of the density of the structure (1,3–1,4 g/cm3) after the passage of guns managed to get a sowing layer with a satisfactory content of agronomic useful lumps. The target group of information consumers in the article - designers, specialists who are engaged in the development of soil working working bodies. [ABSTRACT FROM AUTHOR]

The Lhasa River Basin currently faces severe land degradation. In recent years, several dams have been built on the main stream, whereas, their impact on land desertification remains less elucidated. Herein, we investigated variances of soil properties and microbial communities in biological soil crusts (BSCs) along the valley area of Lhasa River and the mountain slope (altitude gradient) in reservoir area after five years of dam construction. Soil nutrient and water contents, enzyme activities, and N-cycle related functional gene copies significantly increased in reservoir-affected areas and decreased with the increase of mountain slope altitude and the distance away from the reservoir, which were usually degraded soil patches; similarly, the relative abundance of bacteria, fungi and moss in BSCs significantly increased in reservoir-affected areas, whilst that of cyanobacteria was higher in degraded soil patches. The linear and structural equation models also showed that dam construction altered water distribution status of soil surface, which enhanced soil properties, N-cycle and increased the relative abundance of moss of BSCs, and successfully accelerated the development and succession of BSCs in degraded soil. This study firstly reported that dam construction could accelerate the succession process of degraded soil in the reservoir affected area and thus a reference for ecological restoration of desertification soil of the Lhasa River Basin in QTP. [Display omitted] • Investigated variances of soil properties and microbial communities in biological soil crusts (BSCs). • Dam construction affect BSCs development and soil properties significantly. • Soil properties affected by dam construction influence BSCs microbial diversity. [ABSTRACT FROM AUTHOR]

• Rainfall-induced physical crust formation in near-surface soil was characterized. • X-ray CT scanning was employed to investigate changes in the Near-Surface Soil Pore Structure after Drying under varying rainfall durations. • Lower pore volume and denser pore structure were observed in crustal layers. • Near-surface soils show significant dynamic changes in soil structure under dry conditions. • Our results provide insight for agricultural soil management. Rainfall events in arid and semi-arid regions lead to the formation of a physical crust on the soil surface, and such crusts have significant implications for soil hydrological processes. However, previous research has primarily focused on the macroscopic effects of the physical crust, while the influence of soil moisture changes on the soil pore structure is poorly understood. In this study, we simulated two types of physical crusts (structural and depositional) under different rainfall durations using artificial rainfall simulations. We employed X-ray computed tomography (XCT) to analyze the geometric shapes and topological structures of the near-surface soil pores. The results revealed stratified characteristics of soil porosity caused by rainfall-induced physical crust. The porosity in the crustal layer was lower and exhibited a denser pore structure than that of the underlying soil. The thickness of the physical crust varied with the duration of rainfall, with depositional crusts thickening under longer rainfall durations, whereas the opposite was observed for structural crusts. Both types of physical crusts induced significant changes in the pore structure of the upper soil layer, including a decrease in average pore size and an increase in pore density. Analysis of pore connectivity indicated an increase in isolated pores within the physical crust, suggesting a reduction in soil permeability and airflow capacity. This study contributes insights for agricultural soil management in arid and semi-arid regions by revealing the nuanced effects of rainfall-induced physical crusts on near-surface soil pore characteristics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Soil crusts from difference Lake Urmia playa surfaces are investigated. • Clay flats and clay flats-salt crusts have the most stable crusts. • Clay, Organics, silt and NaCl are the key factors in the crust stability. • Large size geologic carbonates as aragonite and dolomite reduce crust stability. • Sand sheets have the least stable crusts due to high sand and geologic carbonates. The recession of lake shores, including the ones of Lake Urmia (LU), and later exposure of the lake bed sediments to wind erosion as a consequence of climate change and drought, is a devastating phenomenon worldwide. In the absence of stable surface crusts, these areas can be the source of airborne dust causing health and environmental issues. The present study aims at investigating the crust formation and development on Lake Urmia playa (LUP) surfaces through physicochemical and morphological studies and to determine the major factors affecting crust stability. To achieve the above goals, 50 soil crust samples from playa surfaces of the western LU playa were collected. The soil crust thickness and compressive strength were determined by a digital micro penetrometer. By means of X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM), the main morphological and chemical factors responsible for the crust development and evolution in LUP were identified. Results showed that crust samples from clay flats (CFs) and clay flats-salt crusts (CF-SC) possessed the most stable crusts with a thickness of 2.2 and 1.9 cm and maximum compressive strength of 6709 and 7399 kPa, respectively, while sand sheets (Sa-sheets) showed weak and locally restricted crust development. Evaluation of correlation coefficients (CC) between soil crust physicochemical properties and crust stability parameters revealed that clay, silt, and organic matter enhance the crust stability and decrease the erodible fraction by increasing the crust thickness, while salt content quantified as Na+ concentration and electrical conductivity increase the firmness of the crusts. Interestingly, total carbonates quantified as calcium carbonate equivalent (CCE) correlated negatively with crust stability although pedogenic calcite is known as cementing agent in soils. XRD together with FTIR spectroscopy revealed that calcite is indeed the predominant mineral form in most soils with the exception of Sa-sheets with the highest share of carbonates, in which aragonite prevailed over calcite. While carbonates of pedogenic origin act as cementing agent, geologic carbonates present as coarse aragonite particles decrease soil stability. Therefore, samples with the highest total carbonate content exhibited the weakest crust, which explains the negative correlation between soil crust and CCE. SEM coupled with Energy Dispersive X-ray (EDX) and elemental mapping revealed that NaCl is the major cementing agent of the soil particles in crusts developed on LU playa surfaces. Its coexistence with phyllosilicates has increased the crust stability and resilience against wind erosion in CF and CF-SC samples while in the Sa-sheet samples, the absence of clay-size minerals (silt and clay) along with the prevalence of geologic carbonates (dolomite and aragonite) and lower NaCl content, limited crust formation and stability. This study emphasizes the importance of the intrinsic soil physicochemical properties together with the secondary (pedogenic) carbonate formation and more importantly the presence of NaCl, as the best determining factors controlling crust formation over LU playa surfaces. [ABSTRACT FROM AUTHOR]

Urban stormwater ponds (SPs) are important for flood protection strategies in areas with heavily sealed soils as they mitigate the negative effects of floods. SPs with temporary waters (TWs) are only flooded when water levels or surface runoffs are high, while SPs with permanent waters (PWs) contain a permanently flooded area. In urban areas, SPs are important secondary habitats for plants and animals as natural aquatic and semi-aquatic habitats are often destroyed during urbanization. In 2017, a large survey on vascular plant diversity of 80 SPs was conducted in the city of Hamburg (Germany). The aim of the study was to analyze plant diversity of TWs and PWs and to identify relationships between plant diversity and different urbanization parameters. In total, 30% of the plant species pool of Hamburg was found in the surveyed SPs representing 0.03% of the total area of Hamburg. We found significant differences in the number and proportion of aquatic, threatened and non-native species between the shoreline and bottom of TWs and PWs. The number and proportion of aquatic species was positively correlated with the proportion of urban green and negatively correlated with the degree of soil sealing in the direct surrounding of SPs. For the proportion of threatened species in the bottom of TWs, a positive relationship was found with the proportion of urban green in the surrounding of SPs. For the number and proportion of non-native species in the shoreline of SPs, negative relationships were found with the proportion of urban green and the number of different habitat types in the surrounding of SPs. Further, a positive relationship with the degree of soil sealing was identified. Our results highlight the nature conservation value of urban SPs for plants and showed the negative effects of urbanization on several plant species groups. • Diverse plant species assemblages were found in the stormwater ponds (SPs) in Hamburg. • 30% of the plant species of Hamburg were found on 0.03% of its total area. • No clear patterns for the influence of urbanization on plant diversity were found. • Patterns differed between the hydrological conditions and zones of SPs. [ABSTRACT FROM AUTHOR]