Intermittent Rainfall Research Articles

Serotype-specific clinical features and spatial distribution of dengue in northern Kerala, India.

Collection and compilation of spatial, meteorological, entomological, and virological data are critical in mitigating climate-sensitive emerging infections like dengue. This study was a holistic attempt to understand the dengue situation in the Kasaragod district of Kerala, India. This cross-sectional study was conducted in 13 health institutions from June to July 2021. Adult patients presenting with fever and testing positive for NS1 ELISA were subjected to Dengue RT-PCR and serotyping. The spatial and clinical features of the RT-PCR-positive patients, the district's meteorological data, and the vector indices were studied. The pre-epidemic months were marked by intermittent rainfall, peak ambient temperature and high larval indices. Among the 136 dengue RT-PCR patients studied, 41.2% had DENV2 followed by DENV1 (22.8%), DENV3 (5.9%) and DENV4 (4.4%); with 25% mixed infections. DENV1 showed a higher risk of gastrointestinal manifestations (80.6%, p=0.019) and musculoskeletal symptoms (77.4%, p=0.026) compared with other serotypes. In the context of dengue hyperendemicity, the possibility of an emerging serotype's dominance coupled with the mixing up of strains should warn the health system regarding future outbreaks. Furthermore, the study emphasizes the importance of monitoring larval indices and the window of opportunity to intervene between environmental predictors and dengue outbreaks.

Experimental study on the effect of process parameters on postcombustion CO2 capture using rotating packed bed technology

AbstractEnvironmental issues are the most discussed in today's industrialized world, and this has always been associated with the emission of greenhouse gases. CO2 emissions, especially from power plants, are considered the major greenhouse gas source. Capturing CO2 from large emission sources is necessary to address the worst impacts of climate change, including more frequent and severe droughts, heat waves, and intermittent rainfall. Conventional post‐combustion CO2 capture has always been questioned because of its high impact on energy costs. Rotating packed bed technology has shown the potential to reduce the cost of CO2 capture. This paper presents an experimental study on an in‐house designed rotating packed bed absorber for the capture of CO2 from a flue gas stream. Effects of process parameters such as rotating speed, liquid‐to‐gas ratio, and monoethanolamine (MEA) concentration on CO2 capture efficiency and overall volumetric mass transfer coefficient were studied. The study showed that as rotor speed increased, the CO2 capture efficiency increased, this can be attributed to higher rotor speed, resulting in more droplet flow, indicating an increase in the area of contact between the flue gas and the MEA solvent. Also, as the concentration of MEA increased CO2 capture efficiency increased, since an increase in concentration results in an increase in the rate of reaction. Finally, the study showed that a rotating packed bed absorber is an efficient unit for CO2 capture since it enhances mass transfer performance.

RAINFALL FORECASTING WITH AN INTERMITTENT APPROACH USING HYBRID EXPONENTIAL SMOOTHING NEURAL NETWORK

Rainfall forecasting is crucial in agriculture, water resource management, urban planning, and disaster preparation. Traditional approaches fail to capture complicated and intermittent rainfall patterns. The “Hybrid Exponential Smoothing Neural Network” is introduced in this study to handle intermittent rainfall forecasting issues. Exponential Smoothing, an established approach for discovering underlying patterns and seasonal fluctuations in time series data, is combined with Neural Networks, which are good at capturing complex linkages and nonlinearities. Using these two methods, this model hopes to deliver a complete rainfall forecasting solution that accounts for short-term changes and long-term patterns. This research uses residuals from the exponential smoothing model and is modeled using a Neural Network. The residual input is transformed using rolling mean. The results show that the hybrid model is able to capture patterns well, but there are still patterns that experience time lag. Experimental results obtained reveal that the hybrid methodology performs better than the model exponential smoothing, implying that the proposed model hybrid synergy approach can be used as an alternative solution to the rainfall time series forecasting. The results show that the Hybrid method can form patterns better than individual exponential smoothing models or neural networks. The RMSSE values for all areas are 1.0185, 1.55092, 1.0872.

Experimental Study on Runoff and Sediment Production of the Fully Weathered Granite Backfill Slope under Heavy Rain in Longling, Yunnan Province

Heavy or intermittent rainfall can cause slopes to become unstable and erode, resulting in significant damage, loss of life, and destruction of property. Targeted management solutions are based on an analysis of slopes’ flow generation and sediment production patterns during periods of rainfall. This study used a fully granite backfill slope as its research subject and examined the features of slope erosion during intermittent rainfall. We examined the processes of slope flow generation and soil erosion during intermittent rain through indoor artificially simulated rainfall experiments. Three intermittent rainfall events with a 220 mm/h intensity were designed during the experiment. Each rainfall event lasted for 60 min, with an interval of 60 min between the events. By analyzing multiple rainfall events, this study reveals the patterns of runoff and sediment yield on different slopes in response to variations in rainfall intensity and slope gradient. The runoff volume on other slope surfaces exhibits a similar pattern in reaction to changes in rainfall events. As the frequency of rainfall events increases, the surface runoff tends to be higher. Additionally, with variations in slope steepness, the runoff volume generally follows an increasing trend. Notably, the slope with a 20° incline shows the smallest runoff volume. The sediment yield on different slope surfaces gradually increases as the slope increases. In particular, on a 20° slope, the sediment yield experiences a substantial increase, indicating that the impact of the slope on the sediment yield becomes more pronounced. In different rainfall events, the morphology of the slope changes due to the influence of gravity and hydraulics, resulting in oscillations in both the average runoff rate and sediment yield. Furthermore, as the slope steepens, the amplitude of these oscillations increases. The process of slope erosion involves three stages: raindrop splash erosion, runoff erosion, and collapse damage. The sequence of slope damage locations is as follows: footslope, mid-slope, and hilltop. For the backfilled slope of completely weathered granite, the artificial slope can be controlled to around 20°. Erosion on the slope mainly occurs after the formation of gullies, and slope management should focus on preventing gully formation before it happens.

Model Test Study of Rainfall Factors on Failure Process of Xiashu Loess Slope with Gravel Layer

Rainfall is an important factor affecting the stability of Xiashu loess slope, so it is particularly important to understand the infiltration law and induction process of rainfall in Xiashu loess slope. In this paper, a Xiashu loess slope model with a slope ratio of 1 : 1.2 is constructed in the model box. The rainfall infiltration law, vertical stress characteristics, pore-water pressure characteristics, and deformation failure mode of the slope under two different rainfall types and four different rainfall degrees are analyzed. The instability and failure mechanism of Xiashu loess slope with gravel layer under different rainfall conditions is studied. The test results show that the influence of rainfall intensity factors on the gravel soil slope is mainly reflected in the degree of erosion of the slope. With the increase in rainfall frequency and intensity, the rainfall infiltration rate gradually increased, reached the highest value after standing, and then decreased with the increase of rainfall intensity. Rainfall has a great influence on the pore-water pressure in the gravel soil slope, and the pore-water pressure at the monitoring point of the slope toe changes the most. The vertical stress curve will change abruptly in the later stage of intermittent rainfall and during continuous rainfall.

Farmer’s Sagaciousness on Climate Change and Adaptation Strategies in Agriculture: A Case Study in Hyatimundaragi Village of Koppala District of Karnataka, India

Climate change is recognized as one of the leading challenges affecting the performance of agriculture and the livelihood of people. Farmers are the hardest hit as they have to continuously respond to climate variations. In order to know farmers' perception of climate change and its impacts and to identify adaptation needs semi-structured questionnaire surveys were carried out in Hyatimundaragii village of Koppala district, Karnataka. Farmers have faced climate variability and noticed increasing temperature, delayed onset of rainfall, intermittent rainfall, prolonged drought conditions, depletion of the water table, untimely filling of water bodies, increased incidence of pests and diseases, livestock diseases, and decreasing soil moisture as the critical factors affecting their cultivation, decrease yield and quality of crop produce. Some of them have started to adapt to these changes by soil conservation measures like the construction of graded bunds, mulching, green manuring and sorghum+pigeonpea intercropping, crop rotation, cultivating drought, pest and disease resistance short duration varieties, providing lifesaving irrigation to crops.

Stability analysis of loose accumulation slopes under rainfall: case study of a high-speed railway in Southwest China

The high and steep slopes along a high-speed railway in the mountainous area of Southwest China are mostly composed of loose accumulations of debris with large internal pores and poor stability, which can easily induce adverse geological disasters under rainfall conditions. To ensure the smooth construction of the high-speed railway and the subsequent safe operation, it is necessary to master the stability evolution process of the loose accumulation slope under rainfall. This article simulates rainfall using the finite element analysis software’s hydromechanical coupling module. The slope stability under various rainfall situations is calculated and analysed based on the strength reduction method. To validate the simulation results, a field monitoring system is established to study the deformation characteristics of the slope under rainfall. The results show that rainfall duration is the key factor affecting slope stability. Given a constant amount of rainfall, the stability of the slope decreases with increasing duration of rainfall. Moreover, when the amount and duration of rainfall are constant, continuous rainfall has a greater impact on slope stability than intermittent rainfall. The setting of the field retaining structures has a significant role in improving slope stability. The field monitoring data show that the slope is in the initial deformation stage and has good stability, which verifies the rationality of the numerical simulation method. The research results can provide some references for understanding the influence of rainfall on the stability of loose accumulation slopes along high-speed railways and establishing a monitoring system.

Unsaturated slopes behavior under antecedent intermittent rainfall patterns: centrifuge and numerical study

Antecedent rainfall is a prime factor for rainfall-induced landslides on unsaturated slopes. The effects of the intermittent behavior of antecedent rainfall on landslide initiation are uncertain. The work described here had the objective of showing the influence of antecedent intermittent rainfall patterns to predict landslide initiation. Soil slope models prepared from silty sand were tested in centrifuge model testing. At first, soil slopes experienced different antecedent rainfall patterns, namely, uniform gap, decreasing gap, and increasing gap, before they were exposed to continuous rainfall until the failure was initiated. The seepage and deformation behaviors of instrumented slopes were evaluated and back-analyzed with soil–water–air coupled hydromechanical finite element analysis using calibrated material parameters and suitable boundary conditions. The evolution of porewater pressure, displacements, and deviatoric strains was found to provide comparable responses. The analysis of incremental velocity clearly showed that times for landslide initiation follow the order of decreasing gap, uniform gap, and increasing gap antecedent rainfall patterns. The study identified that not only cumulative rainfall, but also antecedent intermittent rainfall patterns have a significant effect as a triggering agent and suggested incorporating it as a parameter for landslide early warning mechanisms.

Energy efficiency in transient surface runoff and sediment fluxes on hillslopes – a concept to quantify the effectiveness of extreme events

Abstract. Surface runoff over time shapes the morphology of the landscape. The resulting forms and patterns have been shown to follow distinct rules, which hold throughout almost all terrestrial catchments. Given the complexity and variety of the Earth's runoff processes, those findings have inspired researchers for over a century, and they resulted in many principles and sometimes proclaimed laws to explain the physics that govern the evolution of landforms and river networks. Most of those point to the first and second law of thermodynamics, which describe conservation and dissipation of free energy through fluxes depleting their driving gradients. Here we start with both laws but expand the related principles to explain the co-evolution of surface runoff and hillslope morphology by using measurable hydraulic and hydrological variables. We argue that a release of the frequent assumption of steady states is key, as the maximum work that surface runoff can perform on the sediments relates not only to the surface structure but also to “refueling” of the system with potential energy by rainfall events. To account for both factors, we introduce the concept of relative dissipation, relating frictional energy dissipation to the energy influx, which essentially characterizes energy efficiency of the hillslope when treated as an open, dissipative power engine. Generally, we find that such a hillslope engine is energetically rather inefficient, although the well-known Carnot limit does not apply here, as surface runoff is not driven by temperature differences. Given the transient and intermittent behavior of rainfall runoff, we explore the transient free energy balance with respect to energy efficiency, comparing typical hillslope forms that represent a sequence of morphological stages and dominant erosion processes. In a first part, we simulate three rainfall runoff scenarios by numerically solving the shallow water equations, and we analyze those in terms of relative dissipation. The results suggest that older hillslope forms, where advective soil wash erosion dominates, are less efficient than younger forms which relate to diffusive erosion regimes. In the second part of this study, we use the concept of relative dissipation to analyze two observed rainfall runoff extremes in the small rural Weiherbach catchment. Both flood events are extreme, with estimated return periods of 10 000 years, and produced considerable erosion. Using a previously calibrated, distributed physics-based model, we analyze the free energy balance of surface runoff simulated for the 169 model hillslopes and determine the work that was performed on the eroded sediments. This reveals that relative dissipation is largest on hillslope forms which relate to diffusive soil creep erosion and lowest for hillslope profiles relating to advective soil wash erosion. We also find that power in surface runoff and power in the complementary infiltration flux are during both events almost identical. Moreover, there is a clear hierarchy of work, which surface runoff expended on the sediments and relative dissipation between characteristic hillslope clusters. For hillslope forms that are more energy efficient in producing surface runoff, on average, a larger share of the free energy of surface runoff performs work on the sediments (detachment and transport) and vice versa. We thus conclude that the energy efficiency of overland flow during events does indeed constrain erosional work and the degree of freedom for morphological changes. We conjecture that hillslope forms and overland dynamics co-evolve, triggered by an overshoot in power during intermittent rainfall runoff events, towards a decreasing energy efficiency in overland flow. This implies a faster depletion of energy gradients during events and a stepwise downregulation of the available power to trigger further morphological development.

Greenhouse gas emissions and ammonia loss of maize fertigation with a centre pivot system in the North China Plain

AbstractWhether sprinkler fertigation stimulates greenhouse gas emissions and ammonia loss is an indispensable consideration for nitrogen management. To assess the effect of sprinkler fertigation on N2O, CH4, CO2 and NH3 emissions, three N recommendation methods for summer maize, including the local empirical value, mineral nitrogen method and modified mineral nitrogen method, and three topdressing methods, including no topdressing, one topdressing and two topdressings following intermittent rainfall events, were tested in the 2020 and 2021 seasons. Surface irrigation with fertilizer broadcasting was used as the control treatment. The results indicated that nitrogen topdressing and rainfall promoted soil N2O, CO2 and NH3 emissions but had no obvious effect on CH4 emissions. The increasing nitrogen application rate increased gaseous nitrogen losses of N2O and NH3. Sprinkler fertigation with the modified mineral nitrogen method and two topdressings obtained the greatest yield and nitrogen use efficiency. Compared to the control treatment, the yield and nitrogen use efficiency in the sprinkler fertigation treatments was maximally increased by 20%, and the cumulative NH3 volatilization losses and gaseous nitrogen loss rate were both reduced by 16%, while the cumulative N2O emissions increased by 4%. No significant difference in global warming potential was obtained among all treatments.

Changes in soil hydrodynamic parameters during intermittent rainfall following tillage

The changes in the soil hydrodynamic properties following soil tillage were investigated in rainfall simulation trials of intermittent rain at the Masse experimental station (Soil Erosion LABoratory, SERLAB) in central Italy. The experiments were designed to build a database as representative as possible of situations that may occur in nature. The data collected during the experiments were used to determine the saturated soil hydraulic conductivity, Ks, the soil sorptivity at the antecedent soil–water matric potential Ψi, S, and the flow-weighted mean pore size at Ψi, λm. It was also verified if the energy content of total rainfall after tillage explained the short-term temporal variability of Ks. The results showed that during a sequence of rainfalls with wetting and drying cycles, there was a reduction of both S and Ks by 2.9–3.1 and 1.4–2.2 times, respectively, depending on the plot. This decrease was abrupt for S and more gradual for Ks. The analysis confirmed that Ks decreased as the overall energy dissipated at the soil surface, E, increased. The range of possible Ks values should be expected to become smaller as the dissipated rainfall energy after tillage increases (<30 mm/h for E = 2 kJ/m2 and < 5 mm/h for E = 8 kJ/m2). For this reason, for the prediction and mathematical simulation of the rainfall-runoff transformation process, it is not advisable to limit the investigation to a single hydraulic characterization carried out immediately or shortly after tillage but data should be collected in a relatively long time span after tillage to properly characterize the soil in a condition favourable to surface runoff occurrence. For very high energy values, a recovery mechanism of the hydraulic properties of the altered/compacted layer was observed, but this behaviour should be confirmed by further investigations.

Effect of exposed roots on the erosion characteristics of sloped land based on close-range photogrammetry in a karst rocky desertification region

On sloped land in karst rocky desertification regions, some roots gradually become exposed to the surface due to the low soil-forming rate of the parent rock and shallow natural soil layer. The spatial orientation of these roots varies with the terrain as the plants grow and the surrounding surface erodes. In previous studies, the exposed roots were often used to estimate erosion intensity, but little is known about how exposed roots influence the erosional characteristics of sloped land. In this study, the effects of the orientation of the exposed roots (vertical slope arrangement, parallel slope arrangement, transverse slope arrangement) on the erosion characteristics of sloped land were investigated based on close-range photogrammetry and simulated rainfall experiments. The results showed that there were differences in the responses of the sloped land to erosion based on the different orientations of the exposed roots. In the first four rainfall events, the surface runoff rate was the highest for the parallel slope arrangement, followed by the vertical slope arrangement and transverse slope arrangement. With the occurrence of intermittent rainfall events, this difference gradually decreased. The exposed roots affected the erosional characteristics of sloped land by interfering with the runoff flow path. In most rainfall events, the general trend of eroded sediment yield was parallel slope arrangement > vertical slope arrangement > transverse slope arrangement. The digital elevation model (DEM) constructed by close-range photogrammetry showed that the surface microtopography changed during intermittent rainfall, which resulted in the difference in the relief of sloped land with different exposed root distribution patterns. The volume of soil detached and transported along slopes with parallel slope arrangement was more severe than that on transverse and vertical slopes because the shallow gullies between exposed roots provided a good transport channel for runoff along sloped land. These results provide a reference for understanding the relationship between plant roots and erosion processes in regions of karst rocky desertification.

The unsaturated seepage process and mechanism of internal interfaces in loess-filled slopes during intermittent rainfall

In the “Gully Land Reclamation” project conducted in Yan’an, China, shallow failure in the middle of loess-filled slopes is caused by the unsaturated seepage of rainwater along the internal interface between the original loess slopes and the loess-filled slopes. Although the phenomenon was observed through model test, the particular nature of the unsaturated seepage mechanism remains unclear. To explore this mechanism, we carried out an intermittent rainfall model test on a loess-filled slope, and the volume water content in different areas was continuously monitored. Based on the monitored data, the unsaturated seepage process and mechanism in the internal interface was analyzed by adopting the Fredlund and Xing model and the Childs and Collis-Geroge model. The results indicate that a water accumulation phenome occurs in the middle area of loess-filled slope because of low matric suction in the middle area and high matric suction in the bottom area. In addition, the dynamic process of pore growth and shrinkage at different areas prevents seepage to the bottom area. Furthermore, the regularity of pores at the interface during intermittent rainfall is summarized from a macroscopic perspective based on the matric suction and permeability coefficient. The unsaturated seepage process and mechanism affected by Knudsen diffusion are revealed. Because of the presence of unsaturated seepage, a shallow failure appears in the middle area of a loess-filled slope. The results have a significant impact on the field applications of interfacial impermeable prevention measures.

Insight from a Physical-Based Model for the Triggering Mechanism of Loess Landslides Induced by the 2013 Tianshui Heavy Rainfall Event

Rainfall-induced landslides pose a significant threat to human life, destroy highways and railways, and cause farmland degradation in the Loess Plateau. From 19 June 2013 to 26 July 2013, continuous and heavy rainfall events occurred in the Tianshui area, Gansu Province. This strong rainfall process included four short-term serious rainfall events and long-term intermittent rainfall, triggering many shallow loess landslides. To improve our understanding of this rainfall process as the triggering mechanism of the loess landslides, we conducted the physical-based spatiotemporal prediction of rainfall-induced landslides. By utilizing precipitation data recorded every 12 h from the rain gauge stations and 51 soil samples from within a 50 km radius of the study area, we predicted 1000 physical-based model-calculated pictures of potential landslides, and the slope failure probability (Pf) of the study area was obtained by Monte Carlo simulations. The model was validated by the actual landslide data of the 2013 heavy rainfall event, and the effects of the precipitation process and the trigger mechanism on the landslides were discussed. The results showed that the fourth rainfall event had the best prediction ability, while the third event had the second-best prediction ability. There was a solid linear link between the antecedent precipitation (Pa) and the predicted landslide area (Pls) based on the fitting relationship, indicating that antecedent rainfall may play a significant role in the occurrence of landslides in the region. By comparing the distribution of the predicted results of the four heavy rainfall events with the actual landslide, we observed that the first two rainfall processes may not have been the main reason for slope failure, contributing only to prepare for the landslides in the later period. The superposition of the fourth and third rainfall events finally determined the spatial distribution characteristics of the landslide induced by the 2013 heavy rainfall event.

Experimental Investigation of Water-Retaining and Unsaturated Infiltration Characteristics of Loess Soils Imbued with Microplastics

Microplastics are abundant in agricultural soils and have significant impacts on rainfall infiltration and soil water-retaining capacity. To explore the effect of microplastics on agricultural soil permeability by simulating the rainfall irrigation process, a one-dimensional vertical soil column rainfall infiltration test device was used to study the unsaturated infiltration characteristics of loess soil imbued with microplastics under rainfall conditions. The following conclusions could be obtained: the microplastic content (q), the microplastic particle size (p), and the soil density (γ) have effects on rainfall infiltration; the soil water-retaining capacity would be weakened owing to the existence of microplastics; and intermittent rainfall is preferred in agricultural irrigation. Finally, the permeability coefficient (k) and average flow rate (V) of the unsaturated soil are deduced together, and the relationship between the permeability coefficient (k) and the matrix suction (ψ) of the unsaturated loess soil containing microplastics is calculated by an example, proving good consistency between the experimental results and theoretical calculations. Microplastics represent negative effects on rainfall infiltration and soil water retention, so it is recommended to dispose of them.

Effectiveness and characteristics of atmospheric CO2 removal in croplands via enhanced weathering of industrial Ca-rich silicate byproducts

Enhanced weathering of industrial Ca-rich silicate byproducts in croplands is potentially profitable for large-scale atmospheric CO2 removal; during the weathering process, CO2 dissolves to form HCO3− and CO32− in alkaline soil pore water, which eventually flows into the ocean. However, the effectiveness of such systems is still in doubt, owing to the unrealistic models used for prediction and the insufficient consideration of the dynamic influences of soils on fluid chemistry. We determined the effectiveness of such systems for atmospheric CO2 removal, along with their characteristics, through a set of batch- and flow-through-type laboratory experiments, using andosol and decomposed granite soil as agricultural and non-agricultural soils, respectively, and Portland cement, steelmaking slag, and coal fly ash as industrial byproducts. The results of the batch-type experiments demonstrated that agricultural soils were suitable for CO2 removal, owing to their moderately high pH and Ca concentrations in pore water that prevented intensive calcium carbonate precipitation. The flow-through experiments demonstrated that a higher Ca-content byproduct can have a large atmospheric CO2 removal capacity. However, the magnitude of CO2 removal and its time-dependent behavior were difficult to predict because they were not in conjunction with the changes in the average pH value. This indicated that the diffusive transport of CO2 from the atmosphere-soil interface to deeper soils was more complex than expected. Maximizing CO2 removal requires a better understanding of the diffusive transport of CO2 through gas-filled pore spaces, created by unsteady-state air–water two-phase flow, due to intermittent rainfall.

Forecasting Hourly Intermittent Rainfall by Deep Belief Networks with Simple Exponential Smoothing

Accurate rainfall forecasting is essential in planning and managing water resource systems efficiently. However, intermittent rainfall patterns increase the difficulty of accurately forecasting rainfall values. Deep learning techniques have recently been popular and powerful in forecasting. Thus, this study employed deep belief networks with a simple exponential smoothing procedure (DBNSES) to forecast hourly intermittent rainfall values in Taiwan. Weather factors were used as independent variables to forecast rainfall volume. The simple exponential smoothing data preprocessing procedure was used to deal with the intermittent data patterns. The other three forecasting models, namely the least squares support vector regression (LSSVR), the generalized regression neural network (GRNN), and the backpropagation neural network (BPNN), were employed to forecast rainfall using the same data sets. In addition, genetic algorithms were utilized to determine the parameters of four forecasting models. The empirical results indicate that the developed DBNSES models are superior to the other forecasting models in terms of forecasting accuracy. In addition, the DBNSES can obtain smaller values of RMSE than those in the previous studies. Therefore, the DBNSES model is a suitable and effective way of forecasting rainfall with intermittent data patterns.

Crop Yield Prediction Using Deep Neural Networks

Abstract: Agriculture is undergoing a metamorphosis due to several environmantal and scoal factors. Due to challenges such as global warming, intermittent rainfall patterns and eroding nutrient values of soil, crop yileds have become more upredictable in the last decade. This has resulted in famines, armer suicides and deaths due to hunger. Thus, one of the key objectives of the world health organization is to provide food security globally and also help the agriculture community as a whole whith special emhpasis on low income group countries. This has made crop yield forecasting extremely important. As the crop yield depends on several factors which are highly uncorrelated in nature, hence machine learing based appraoches have been employed for the purpose. In this paper a deep neural network approach has been proposed along with the discrete wavelet transfrom to forecast crop yields. The wavelet transform has been used as a filtering techniques to remove local disturbances from the data, and deep neural networks have been used for pattern recognition and forecasting. The evaluation of the proposed system has been evaluated in terms of the mean absolute percentage error, accuracy and regression. It has been found that the proposed work outperforms existing baseline techniques in terms of the accuracy of forecasting.

Water inputs across the Namib Desert: implications for dryland edaphic microbiology

Microbes have a dominant role in nutrient cycling processes in the world’s deserts, where growth and activity are limited by the availability of water. In order to understand the dynamics of water availability in a desert system and how it may affect the soil microbiome, we analysed soil temperature and relative humidity fluctuations recorded between April 2018 and April 2020 across a precipitation gradient in the Namib Desert and compared them with recorded data from satellites and nearby weather stations. This allowed us to assess the possible impact of fog and rain events in terms of biologically-available water. Using published literature on the water activity limits for various physiological processes in microorganisms, we were able to infer the annual ‘metabolic windows’ for desert microbial communities across the longitudinal precipitation gradient. Specifically, soil surface microbial communities were estimated to have the capacity for active growth for an average of 184- 363 hours per year with the duration heavily dependent on intermittent rainfall events. During the relatively wet period of April 2018 - March 2019, the maximum growth window was found in the hyper-arid central region of the transect (approximately 100 km from the coast). During the dryer 2019- 2020 period, there was almost no predicted growth capacity in the hyper-arid region but substantial metabolic windows both near the coast and for the eastern inland areas, where water input comes in the form of fog and moist coastal air, and higher rainfall, respectively. As the first detailed study of the temperature and relative humidity characteristics of Namib Desert near-surface soils, this study provides valuable insights into the biogeography of microbial communities. In addition, the estimates for organismal functionality calculated in this study offer a baseline for future quantitation of the impacts of climate change on the functional capacity of desert soil microbiomes.

Physical Model Study of an Intermittent Rainfall-Induced Gently Dipping Accumulation Landslide

Many slope failures have been observed in deep-cutting gorges in Southwest China due to rainfall events. This study conducted model-based tests of the failure of a gently dipping accumulation slope caused by intermittent rainfall. The physical model was established by configuring soil samples based on similarity theory and direct shear test data. Intermittent rainfall was simulated by supplying surface runoff and bottom pressure water of the slope. The deformation, earth pressure, and pore pressure were observed during the test using a series of transducers. The results of this research showed that slope failure was first initiated at the toe of the slope. Staged sliding failure then occurred, which spread the unstable zone to the trailing edge of the slope. As infiltration of rainwater continued, the pore pressure increased and the matric suction and effective stress at the bedrock surface decreased, causing failure of the slope.