Absence Of Vegetation Research Articles

Thermokarst landscape exhibits large nitrous oxide emissions in Alaska’s coastal polygonal tundra

Global atmospheric concentrations of nitrous oxide have been increasing over previous decades with emerging research suggesting the Arctic as a notable contributor. Thermokarst processes, increasing temperature, and changes in drainage can cause degradation of polygonal tundra landscape features resulting in elevated, well-drained, unvegetated soil surfaces that exhibit large nitrous oxide emissions. Here, we outline the magnitude and some of the dominant factors controlling variability in emissions for these thermokarst landscape features in the North Slope of Alaska. We measured strong nitrous oxide emissions during the growing season from unvegetated high centered polygons (median (mean) = 104.7 (187.7) µg N2O-N m−2 h−1), substantially higher than mean rates associated with Arctic tundra wetlands and of similar magnitude to unvegetated hotspots in peat plateaus and palsa mires. In the absence of vegetation, isotopic enrichment of 15N in these thermokarst features indicates a greater influence of microbial processes, (denitrification and nitrification) from barren soil. Findings reveal that the thermokarst features discussed here (~1.5% of the study area) are likely a notable source of nitrous oxide emissions, as inferred from chamber-based estimates. Growing season emissions, estimated at 16 (28) mg N2O-N ha−1 h−1, may be large enough to affect landscape-level greenhouse gas budgets.

CFD with LIDAR applied to buildings and vegetation for environmental construction

The influence of urban vegetation on buildings, particularly regarding the alteration of wind patterns, poses a significant challenge for building designers and managers. This paper presents recommendations for a health reference guide that are graphically and accurately depicted. The research applied Building Information Modelling (BIM) methodology and Computational Fluid Dynamics (CFD) to visualize urban comfort conditions. The results were used to evaluate two simulation scenarios aimed at studying the effect of green infrastructure on wind patterns. The first scenario considered the absence of vegetation, while the second included green infrastructure with specimens from two different species. The findings suggest potential improvements in the quality of life for the general population, particularly for individuals with respiratory allergy issues.

Evaluation and development of surface layer scheme representation of temperature inversions over boreal forests in Arctic wintertime conditions

Abstract. In this study, the Noah land surface model used in conjunction with the Mellor–Yamada–Janjić surface layer scheme (hereafter, Noah-MYJ) and the Noah multiphysics scheme (Noah-MP) from the Weather Research and Forecasting (WRF) 4.5.1 mesoscale model are evaluated with regard to their performance in reproducing positive temperature gradients over forested areas in the Arctic winter. First, simplified versions of the WRF schemes, recoded in Python, are compared with conceptual models of the surface layer in order to gain insight into the dependence of the temperature gradient on the wind speed at the top of the surface layer. It is shown that the WRF schemes place strong limits on the turbulent collapse, leading to lower surface temperature gradient at low wind speeds than in the conceptual models. We implemented modifications to the WRF schemes to correct this effect. The original and modified versions of Noah-MYJ and Noah-MP are then evaluated compared to long-term measurements at the Ameriflux Poker Flat Research Range, a forest site in interior Alaska. Noah-MP is found to perform better than Noah-MYJ because the former is a two-layer model which explicitly takes into account the effect of the forest canopy. Indeed, a non-negligible temperature gradient is maintained below the canopy at high wind speeds, leading to overall larger gradients than in the absence of vegetation. Furthermore, the modified versions are found to perform better than the original versions of each scheme because they better reproduce strong temperature gradients at low wind speeds.

Trapping of microplastics and other anthropogenic particles in seagrass beds: Ubiquity across a vertical and horizontal sampling gradient

Seagrass beds can trap large amounts of marine debris leading to areas of accumulation, known as ‘sinks’, of anthropogenic particles. While the presence of vegetation can enhance accumulation, less is known about how the trapping effect changes from vegetated to less vegetated patches. To test this, vegetation and sediment were sampled along a vegetation percent cover gradient from the centre of seagrass beds to nearby less vegetated patches. To determine whether trapped particles can lead to increased accumulation in associated fauna, gastropods were also collected from the transects laid across this gradient. Extracted anthropogenic particles were counted and characterised. Particles were detected in all sample types and reached quantifiable limits in at least 50% of sediment and gastropod samples. There was no significant difference in the distribution of particles found in seagrass beds compared to less vegetated patches, suggesting other factors contribute to the trapping efficiency of biogenic habitats besides simply the presence or absence of vegetation.

Relationship between Carbon Sequestration and Soil Physicochemical Parameters in Northern Campeche, Mexico

For decades, mangroves have been exposed to various pressures, resulting in the loss of large swathes around the world. For this reason, ecological restoration actions are presented as alternatives to recover mangroves that can restore their ecosystem services while helping to mitigate climate change’s effects. Mangroves are crucial, as they capture and sequester carbon in biomass and soil, highlighting their importance in environmental conservation and in the fight against climate change. In this research, the amount of carbon sequestered in a mangrove area restored eight years ago and its relationship with soil physicochemical parameters were evaluated and compared to those of a reference forest. Soil cores were collected at a depth of 30 cm from both sites, and in situ measurements of physical chemistry were made at different depths. In addition, soil salinity, bulk density, and carbon concentration were determined. The results revealed a similar amount of carbon sequestered both in the reference forest (BR) (470.17 ± 67.14 Mg C/ha) and in the restoration area (RA) (444.53 ± 86.11 Mg C/ha) (p > 0.05). A direct relationship was observed between carbon sequestration and soil depth. In the case of the RA, a direct relationship was found between carbon sequestration and soil salinity. In conclusion, the results of this study indicate that the behavior of carbon sequestration in soil is determined by the physicochemical conditions in both the BR and the RA, as well as by the presence or absence of vegetation.

Standards for shallow landslide identification in Brazil: Spatial trends and inventory mapping

Mapping shallow landslide inventories represents the initial stage in conducting susceptibility, vulnerability, and risk analyses. The identification of areas with a history of landslides, both past and current events, enables the detection of spatio-temporal patterns and facilitates the evaluation of morphological and geological factors. Shallow landslides are frequent in Brazil, especially along the Brazilian south and southeastern coast. Despite their high frequency, the recognition and mapping of these landslides are inadequately developed due to the absence of established mapping guidelines. This resulted of limited investments by Brazilian authorities in initiatives aimed at preventing and mitigating mass movements. Thus, the aim of this study is to establish criteria for the recognition and mapping of shallow landslides in Brazil and to evaluate their applicability in susceptibility analysis. The study area is located in Itaóca and Apiaímunicipalities, São Paulo state, southeastern Brazil. Criteria for shallow landslide recognition were created based on the absence of vegetation, shape and size, drainage network distance, slope position, planar rupture surface, and altimetric variation. An extensive landslide interpretation was carried out using a set of free access Google Earth Pro images. Susceptibility maps were developed through a bivariate statistical approach, specifically the Informative Value method. The outcomes demonstrated that incorporating the deposition area in susceptibility studies for shallow landslides led to modifications in the final mapping, a slight reduction in validation rates, and, notably, an impact on the influence of the thematic variable curvature. Therefore, it is clear that the criteria used for landslide inventory maps have a significant effect on the accuracy of susceptibility maps and should be a critical consideration in studies related to this subject.

Metagenomic and genomic analysis of heavy metal-tolerant and -resistant bacteria in resource islands in a semi-arid zone of the Colombian Caribbean

Bacteria from resource islands can adapt to different extreme conditions in semi-arid regions. We aimed to determine the potential resistance and tolerance to heavy metals from the bacterial community under the canopy of three resource islands in a semi-arid zone of the Colombian Caribbean. Total DNA was extracted from soil and through a metagenomics approach, we identified genes related to heavy metal tolerance and resistance under the influence of drought and humidity conditions, as well as the presence or absence of vegetation. We characterized the genomes of bacterial isolates cultivated in the presence of four heavy metals. The abundances of genes related to heavy metal resistance and tolerance were favored by soil moisture and the presence of vegetation. We observed a high abundance of resistance genes (60.4%) for Cu, Zn, and Ni, while 39.6% represented tolerance. These genes positively correlated with clay and silt content, and negatively correlated with sand content. Resistance and tolerance were associated with detoxification mechanisms involving oxidoreductase enzymes, metalloproteases, and hydrolases, as well as transmembrane proteins involved in metal transport such as efflux pumps and ion transmembrane transporters. The Bacillus velezensis C3-3 and Cytobacillus gottheilii T106 isolates showed resistance to 5 mM of Cd, Co, Mn, and Ni through detoxification genes associated with ABC pumps, metal transport proteins, ion antiporter proteins, and import systems, among others. Overall, these findings highlight the potential of bacteria from resource islands in bioremediation processes of soils contaminated with heavy metals.

Radiocarbon dates from the Netherlands and Doggerland as a proxy for vegetation and faunal biomass between 55 and 5 ka cal bp

ABSTRACTThree hundred forty‐one radiocarbon dates from the Groningen radiocarbon database are compiled in this study. They show for the first time that organic sediment samples from the eastern Netherlands and mammal bones from Doggerland reflect shifts in the presence and the density of vegetation (food for herbivores) and mammal biomass during the last ice age (Weichselian Stage, ~119–14.7 ka cal bp). Comparison with oxygen isotope curves of Greenland ice cores and geomorphological data shows that cold climate, in particular during the younger part of the Weichselian Middle Pleniglacial and during the Late Pleniglacial, and related scarcity or even absence of vegetation, were limiting factors for the carrying capacity of the landscape and thus for the population density of large herbivores during the period covered by 14C dating (last ca. 55 000 years). A ‘fossil gap’ during the Late Pleniglacial lasted ca. 13 000 years from ca. 28 to 15 ka cal bp. Previous research from the nearby Eifel region in Germany shows that environmental conditions were less extreme (‘refugium conditions’) than in the Netherlands, taking into account the continuous presence of spores of coprophilous fungi in the Eifel, indicating uninterrupted food supply for herbivores.

Response of CO2 and CH4 emissions from Arctic tundra soils to a multifactorial manipulation of water table, temperature and thaw depth

Significant uncertainties persist concerning how Arctic soil tundra carbon emission responds to environmental changes. In this study, 24 cores were sampled from drier (high centre polygons and rims) and wetter (low centre polygons and troughs) permafrost tundra ecosystems. We examined how soil CO2 and CH4 fluxes responded to laboratory-based manipulations of soil temperature (and associated thaw depth) and water table depth, representing current and projected conditions in the Arctic. Similar soil CO2 respiration rates occurred in both the drier and the wetter sites, suggesting that a significant proportion of soil CO2 emission occurs via anaerobic respiration under water-saturated conditions in these Arctic tundra ecosystems. In the absence of vegetation, soil CO2 respiration rates decreased sharply within the first 7 weeks of the experiment, while CH4 emissions remained stable for the entire 26 weeks of the experiment. These patterns suggest that soil CO2 emission is more related to plant input than CH4 production and emission. The stable and substantial CH4 emission observed over the entire course of the experiment suggests that temperature limitations, rather than labile carbon limitations, play a predominant role in CH4 production in deeper soil layers. This is likely due to the presence of a substantial source of labile carbon in these carbon-rich soils. The small soil temperature difference (a median difference of 1 °C) and a more substantial thaw depth difference (a median difference of 6 cm) between the high and low temperature treatments resulted in a non-significant difference between soil CO2 and CH4 emissions. Although hydrology continued to be the primary factor influencing CH4 emissions, these emissions remained low in the drier ecosystem, even with a water table at the surface. This result suggests the potential absence of a methanogenic microbial community in high-centre polygon and rim ecosystems. Overall, our results suggest that the temperature increases reported for these Arctic regions are not responsible for increases in carbon losses. Instead, it is the changes in hydrology that exert significant control over soil CO2 and CH4 emissions.

Interannual variability of ground surface thermal regimes in Livingston and Deception islands, Antarctica (2007–2021)

AbstractThe absence of vegetation in most ice‐free areas of Antarctica makes the soil surface very sensitive to atmosphere dynamics, especially in the western sector of the Antarctic Peninsula, an area within the limits of the permafrost zone. To evaluate the possible effects of regional warming on frozen soils, we conducted an analysis of ground surface temperatures (GSTs) from 2007 to 2021 from different monitoring sites in Livingston and Deception islands (South Shetlands archipelago, Antarctica). The analysis of the interannual evolution of the GST and their daily regimes and the freezing and thawing indexes reveals that climate change is showing impacts on seasonal and perennially frozen soils. Freezing Degree Days (FDD) have decreased while Thawing Degree Day (TDD) have increased during the study period, resulting in a balance that is already positive at the sites at lower elevations. Daily freeze–thaw cycles have been rare and absent since 2014. Meanwhile, the most common thermal regimes are purely frozen – F1 (daily temperatures < = −0.5°C), isothermal – IS (ranging between −0.5°C to +0.5°C), and purely thawed – T1 (> = +0.5°C). A decrease in F1 days has been observed, while the IS and T1 days increased by about 60 days between 2007 and 2021. The annual number of days with snow cover increased between 2009 and 2014 and decreased since then. The GST and the daily thermal regimes evolution point to general heating, which may be indicative of the degradation of the frozen soils in the study area.

The birds of Cameroon: bird survey in a forest plain of the Congo basin forest (Oveng, Cameroon) confirms the great diversity of birds linked to the vegetation of the second largest biodiversity reserve in the world as well as the distribution pattern of taxa

We carried out a bird survey in the Oveng plain in the Congo Basin Forest to investigate the avifauna as well as to explore the abundance, diversity and distribution of taxa. To obtain abundance of bird species and analyze their diversity and distribution, we used the mist net method for bird sampling for five months and performed analyzes with SAS/STAT and PAST software, respectively; moreover, to compare the diversity and dominance of the Oveng plain to other plains already explored, we proceeded to a simple comparison for a small sample, placing the values in a double-entry table and analyzing them. We captured 146 individuals belonging to 22 bird families and compared to previous surveys in this region, we recorded three new species, Campethera maculosa, Buccanodon duchaillui and Alethe diademeta; the birds caught were mainly sedentary and the rest were a mixture of intra-African, seasonal and Palearctic migrants, etc. Values ​​of the diversity indices show a great avifaunistic diversity within the Oveng site; thus, the Shannon-Wiener index (H’= 3.09) expresses the high number of the species within the Oveng avifauna while the Equitability index (J’=0.83) reveals an absence of dominance of one species and therefore an equal distribution of individuals within species. The Simpson index (λ=0.92) supports abundant species representation in Oveng’s birdlife due to the presence of year-round vegetation. The distribution pattern of taxa appeared directly linked to vegetation. Comparison of the diversity and dominance of plains avifauna supports a close relationship between the presence of vegetation and a high diversity of birds and that between an absence of vegetation and a more pronounced dominance.

Cracking process in expansive soil with and without vegetation covers in dry and rainy seasons at field scale

ABSTRACT The presence of desiccation cracks in the soil alters its hydromechanical behavior, increasing the soil's water infiltration capacity, mobilizing the potential for expansion. This may affect the performance of the structural elements of the construction. This study aimed to evaluate the mechanics of expansion, contraction and cracking of the expansive soil of Paulista - Pernambuco, Brazil, through field trials, subject to wetting cycles and drying. The studied soil is a sandy silty clay of high compressibility with medium to very high expansion potential. The process of formation and propagation of cracks was analyzed using digital images and the monitoring of samples subjected to drying and wetting cycles. The indices of crack geometry increased with the advancement of desiccation but did not stabilize. During the wetting period, they tend to close. The pattern of cracks in the tests varied according to the presence or absence of vegetation. It was concluded that the vegetation cover has a significant influence on the standardization and the crack formation and propagation process.

Nonlinear wave propagation in a vegetated sandbar-lagoon system

The sandbar-lagoon system presents a rich variety of values. At the same time, the degradation of ecosystems and coastal erosion caused by human activities and climate change are even more severe. A series of ecological conservation and restoration projects focused on vegetation rehabilitation have been implemented. However, there is insufficient scientific evidence to guide coastal engineering in the presence of vegetation. In this paper, ten tests were presented to experimentally investigate nonlinear wave propagation in a vegetated sandbar-lagoon system. The following conclusions can be obtained. In the absence of vegetation, the low-frequency wave energy proportion gradually increases with the rise of incident wave height. Double-peaked and even multi-peaked spectra are notable throughout the propagation in tests with larger incident wave heights. Wave height decay and wave energy dissipation due to vegetation effects increase as the incident wave height increases. The dependence of the wave energy dissipation induced by vegetation on the incident wave energy (the square of wave height) presents a linear relationship. Vegetation plays an important and complex role in both sea-swell wave and infragravity wave attenuation.

Mapping the sensitivity of land degradation in the Ouergha catchment (Morocco) using the MEDALUS approach

Soil degradation is a global phenomenon affecting the productivity of agricultural land. Due to the low vegetation cover and the aggressive climate, Morocco presents a significant case of soil degradation through erosion and desertification. The Ouergha catchment is highly vulnerable to this scourge. The objective of this study was to assess the sensitivity of land to degradation in the Ouergha catchment area. The MEDALUS approach, widely used in the Mediterranean region, was used to assess the sensitivity of soils to degradation/desertification. This approach integrates four indicators that strongly influence this phenomenon (climate, soil, vegetation and human pressure). The results show that more than half of the study area has a medium sensitivity of land to degradation. The critical areas represent 16.2% and correspond to bare land characterized by steep slopes and absence of vegetation. Low sensitivity areas occupy a limited proportion of 21.9% and correspond to wet summits and conserved forest areas. Climate change could lead to a further increase in areas susceptible to degradation.

Multiple approach for assessing lagoon environmental status based on water bodies quality indices and microplastics accumulation

Lagoon environments, like all the marine-coastal areas, offer a wide variety of ecosystem services, but at the same time are affected by pressing human activities that lead to deterioration of the environmental quality, loss of biodiversity, habitat destruction and pollution. Since the well-being of population and local economy depend on the environmental status of these ecosystems, it is essential to adopt long-term management tools to achieve the Good Environmental Status sensu European Marine Strategy Framework Directive and Water Framework Directive. A Nature 2000 site (Lesina lagoon, south Italy) was assessed within a project aimed at protecting and restoring biodiversity and lagoon habitat through integrated monitoring, suitable management, and good practices. Here we provide an assessment of the lagoon integrity based on a multi-metrics approach, highlighting match/mismatch among environmental quality indicators and microplastics (MP) pollution. Some environmental quality indices based on ecosystem components as vegetation, macroinvertebrates and water trophic variables were applied together with an accurate evaluation of MPs abundance, distribution, and composition to assess the ecological status of Lesina lagoon before and after cleaning actions with litter removal. Overall, all the ecological descriptors outlined a clear lagoon spatial gradient, with a western saltier and organic-enriched area characterized by the absence of vegetation, macrozoobenthos with lower diversity and richness and high MPs occurrence. The focus on macrozoobenthos, considered as a key component of the lagoon ecosystem, identified much more sites in “poor” status than the other indicators here considered. Moreover, it was found a negative relationship between the Multivariate Marine Biotic Index and MPs items in sediment, suggesting that MP pollution has a negative impact on macrobenthic fauna, concurring to the deterioration of the benthic ecological status.

Precambrian aeolian systems: A unique record?

The Precambrian is associated with a set of geologically unique palaeoenvironmental conditions arising from differences in the Earth’s atmosphere, biosphere and geosphere. The extent to which these conditions operated to generate an aeolian stratigraphic record that is geologically distinct from that of the Phanerozoic remains poorly understood. This study presents a quantitative comparison of the preserved sedimentary architectures of 87 globally distributed aeolian successions from the Precambrian (30 case studies) and the Phanerozoic (57 case studies). Compared to those of the Phanerozoic, Precambrian aeolian successions are characterised by: (1) thinner aeolian dune sets, mostly documenting the accumulation of small, rapidly migrating barchan dunes; and (2) a greater occurrence of sandsheet, zibar, and damp and wet interdune deposits, many occurring interdigitated with non-aeolian strata. The nature of the Precambrian aeolian stratigraphic record reflects in part the absence of sediment-stabilizing terrestrial vegetation: compared to Phanerozoic systems developed since the evolution of land plants, aeolian processes (erosion, transport and deposition) were more active, even under markedly more humid climates. Precambrian aeolian successions record greater evidence of fluvial and marine incursions into contiguous aeolian dune fields. Water tables were commonly elevated close to the level of the accumulation surface for protracted episodes; extensive damp and wet substrates restricted the availability of dry sand for aeolian dune construction, thereby limiting dune size. In some Precambrian aeolian systems, sediment supply was additionally restricted by the development of cryptobiotic films and crusts that preferentially developed on damp substrates in the absence of vegetation. Common fluvial and marine aqueous interactions promoted the reworking of aeolian dunes into sandsheet deposits; many such accumulations likely represent eroded remnants of larger aeolian dune fields. Given the absence of vegetation-induced sediment binding and baffling, and wind-buffering effects, coarser sand fractions were more readily transported by the wind in the Precambrian; this led to the preferential development of coarse-grained zibar deposits. This study demonstrates how the Precambrian aeolian sedimentary record is geologically distinct from that of the majority of the Phanerozoic, providing new insights into the controlling factors that governed aeolian sedimentation during the Precambrian through interactions between the geosphere, biosphere and atmosphere.

Ocellated lizard predation patterns on red-legged partridge nests in olive groves

In this study, we evaluated predation of the ocellated lizard on red-legged partridge nests in an olive grove in southern Spain over three consecutive years. The microhabitat characteristics of prey nests are analysed through comparison with successful nests. We found only 13 nests predated by lizards during the study period. This number was three times lower than that of nests that failed due to causes related to agricultural practices or human activity in the same period and study area. A few of the nests were predated by mammals more than they were preyed upon by lizards. The nests preyed on by lizards were associated with proximity to their refuge areas (e.g. stone piles, old buildings with holes, or rabbit burrows). The characteristics of the olive grove (e.g. drip irrigation and absence of vegetation under the olive trees) may favour the ocellated lizards' search-and-hunt strategy, which allows a lizard to readily find a nest if it is inside the lizard's territory and close to its refuge. We propose management strategies for reducing lizard-related nest losses. However, we argue that olive grove intensification is a major cause of partridge nest failure rather than predation by lizards and other predators.

Tsunami Vulnerability and Risk Assessment in Banyuwangi District using machine learning and Landsat 8 image data

The tsunami is a disaster that often occurs in Indonesia, there are no valid indicators to assess and monitor coastal areas based on functional land use and based on land cover which refers to the biophysical characteristics of the earth's surface. One of the recommended methods is the vegetation index. Vegetation index is a method from LULC that can be used to provide information on how severe the impact of the tsunami was on the area.In this study, an increase in the vegetation index was carried out using machine learning. The purpose of this study was to develop a tsunami vulnerability assessment model using the Vegetation Index extracted from Landsat 8 satellite imagery optimized with KNN, Random Forest and SVM. The stages of study, are: 1)extraction Landsat 8 images using algorithms NDVI, NDBI, NDWI, MSAVI, and MNDWI; 2) prediction of vegetation indices using KNN, Random Forest, and SVM algorithms. 3) accuracy testing using the MSE, RMSE, and MAE,4) spatial prediction using the Kriging function and 5) tsunami modelling vulnerability indicators. The results of this study indicate that the NDVI interpolation value is 0 - 0.1 which is defined as vegetation density, biomass growth, and moderate to low vegetation health. the NDWI value is 0.02 - 0.08 and the MNDWI value is 0.02 - 0.09 which is interpreted as the presence of surface water along the coast. MSAVI is a value of 0.1 – 0 which is defined as the absence of vegetation. The NDBI interpolation value is -0.05 - (-0.08) which is interpreted as the existence of built-up land with social and economic activities. From the results of research on the 10 areas studied, there are 3 areas with conditions that have a high level of tsunami vulnerability. 2 areas with medium vulnerability and 5 areas with low vulnerability to tsunami.

Modern relief formation of the northern Aral region under the conditions of the sea regression

The article examines the modern processes of relief formation in the Northern Aral Sea during the period of sea regression and the factors of their formation. The study aims to determine the predominant types of relief formation processes under the conditions of sea regression and the impact of an arid climate. The research methodology combines field observations, interpretation of remote sensing data, digital photogrammetric analysis of aerial photographs, and data processing in GIS. As a result of the study, a map of the modern land cover of the studied area of the Northern Aral Sea region was created. 13 types of cover were identified: wastelands (unused lands), lands occupied by settlements, arable land, wetlands, grasses, steppe with sparse vegetation, water surface, drained bottom of the Aral Sea, fixed sands, shifting sands, saline, and takyrs. The absence of vegetation indicates active gravitational processes and wind erosion. Several villages have been identified that are subject to the adverse effects of mobile sands; these are Kosaman, Akespe, Akbasty, Bogen, etc. In the villages of Akespe and Akbasty, residential houses and household premises of residents are covered with mobile sands. The relative height between the base and the crest of the dune, on average, is 2 meters. The development area of shifting sands in Akespe village is 1.68 km2, and in the village of Akbasty is about 1.62 km2. The values of the load factor of conditional cattle on pastures in the study area, where a high coefficient is noted in the village of Akbasty, are calculated. The development and implementation of environmental management measures in the conditions of adaptation of the environment and human activity to the increasing processes of climate aridization and its consequences become relevant.

Flow in multi-layered vegetated compound channels with different bank slopes

Bank angle and floodplain vegetation emergence determine the flow nature in a compound channel. Two sets of 45° and 90° bank angle compound channel is considered in the present work. Each set considers three cases of vegetation arrangements: no vegetation, multi-layered fully submerged, and multi-layered partially emergent. The flow characteristics like velocity, Reynolds shear stress (RSS), and turbulent kinetic energy (TKE) do not vary much in the cross section in the absence of vegetation. However, with vegetation, the slopes and nearby region are affected the most as it acts as an intermediary region between the main channel and floodplain. An analysis of the anisotropic invariant map shows the dominance of the transverse component in the slopes compared to the main channel and floodplain. The velocity in and around the slopes is higher for steep slopes (90°) compared to a gradual slope (45°) compound channel. The streamwise RSS and bursting events also show higher magnitude near the channel bed in and around the sloping region. This indicates the instability of the steep banks compared to gradual bank slopes. The increase in floodplain vegetation emergence also affects the slopes. The magnitude of RSS and TKE in the slopes is higher with greater vegetation emergence in the floodplain. This shows the higher vulnerability of the slopes in the presence of higher vegetation emergence. From the hydraulic engineering perspective, this study will be helpful in the field of understanding the failure of banks and ways to maintain their stability.