Moisture Values Research Articles

Linking geographical origin with nutritional, mineral, and visual proprieties of pinhão (Araucaria angustifolia seed) from the south of Brazil.

The effect of harvest location on cooked pinhão seeds (Araucaria angustifolia) was investigated with regard to its centesimal composition, minerals, and color, and later correlated with environmental and soil variables. Significant differences between cooked pinhão from various harvesting locations were seen; also, principal component analysis was performed for the minerals, protein, moisture, total starch, and color parameters. The geographic location was one of the most important factors. Caçador presented greater differences: lower values for moisture, minerals, geographic parameter, and color characteristics. However, nearby localities, such as Cruz Machado with Bituruna and Lapa with São João do Triunfo, presented similar overall values for minerals and geographic parameters. Each regional geographic location was able to present unique characteristics so that the principal component analysis categorized it in specific quadrants, which is also in agreement with the CIELAB color space. However, hierarchical tree exhibited that CAÇ was the most distinct, due to the most distant municipality, presenting a unique microbiome. The pinhão is a source of various nutrients, which contributes to healthy dietetic daily values. It provides from 20% to 30% of dietary fiber, Cu (42.2%), P (31.1%), K (23.5%), and Zn (22.1%), while also providing quantities of Mg (12.9%), Mn (12.4%), Fe (11.5%), and Ca (6.4%). Therefore, it is possible to obtain food products based on cooked pinhão that contain many nutritional components associated with human health benefits. PRACTICAL APPLICATION: The pinheiro-do-paraná is a conifer that is currently endangered. However, the commercial use of its seeds may be key to guaranteeing its preservation, in addition to strengthening the economies of households and small producers. The pinhão collected from a large area of Araucária forests, after subsequent boiling, removal of the almond, grinding, and freezing provides large amounts of carbohydrates, higher dietary fiber content, resistant starch, and large quantities of Cu, P, K, and Z, in addition to significant amounts of Mg, Mn, Fe, and Ca. All of these are desirable characteristics that increase the value of pinhão.

Impact of the agglomeration process on the flow, reconstitution, and antioxidant properties of an Andean berry powder mix

BACKGROUND: There is consumer interest in berries due to their nutritional properties, especially biologically active compounds. Spray drying technologies improve products stability and shelf life, and the agglomeration process subsequently enhances powder instantaneousness and flow properties. OBJECTIVE: The aim was to evaluate the effect of the fluidized bed agglomeration process on flow, reconstitution, and antioxidant properties of cape gooseberry, strawberry, and blackberry powder mix obtained by spray drying and a water and vitamin C binding solution. METHODS: A face-centered central composite design with 15 experiments was used; independent variables were fluidization temperature (T), binder solution atomization pressure (P), and process time (t), while dependent variables were moisture, solubility, wettability, particle size, antioxidant capacity, total phenols, Vit. C, β-carotenes (β-car), and total anthocyanins. RESULTS: The best process conditions from experimental optimization were T = 70 °C, P = 1.1 bar, and t = 29.1 min. This agglomerated product had low moisture values, good solubility, and 0.5 min wettability; the values for Vit. C = 246.4±3.4 mg/100 g db, β-car = 4.0±0.5 mg/100 g db, and total anthocyanins = 230.7±3.0 mg C3G/100 g db were noteworthy. CONCLUSIONS: An agglomerate berry-based powder product was obtained with 100% Vit. C RDA (Recommended Dietary Allowances) and 15% vitamin A RDA. Flow and instantaneousness properties of the agglomerated powder also significantly improved with the applied process.

Active packaging film of chitosan and Santalum album essential oil: Characterization and application as butter sachet to retard lipid oxidation

Chitosan with sandalwood (Santalum album) essential oil (SEO) using malic acid as solvent were evaluated as an active packaging film. It was applied as sachet to butter packaging. The effects of SEO concentration (0.5 %, 1 % and 2 % v/v) on chitosan film properties were studied by measuring the equilibrium moisture content, solubility, water vapor permeability (WVP), mechanical, optical, heat sealability, antioxidant properties, surface morphology and thermostability. SEO showed a significant effect on the film properties except for the puncture properties and the equilibrium moisture values. SEO promoted a significant decrease in tensile strength from 5.78 to 2.99 MPa, Young’s Modulus (YM) from 35.74 to 6.81 MPa, WVP from 6.70·10−11 to 3.34·10−11 g/m·s·Pa, and sealability from 195.20 to 107.94 N/m. The antioxidant properties of the films were improved with the presence of SEO. The addition of SEO significantly improved the UV-barrier of the films. The color and transparency of the samples showed significant variations by the addition of SEO. The active packaging film was evaluated as butter sachet. After 3 months of butter storage, a significant decrease of the thiobarbituric acid reactive substances was observed, showing a 36 % decrease in the lipid oxidation compared to unpackaged samples. The films are completely water-soluble and can be easily removed from foodstuffs after use without generating solid wastes.

What causes a heavy precipitation period to become extreme? The exceptional October of 2018 in the Western Mediterranean

The Mediterranean region is particularly exposed to heavy precipitation and flash flooding. Every autumn the region is affected by these weather-related hazards, frequently with immense costly and deadly consequences. What makes an already potentially damaging period in terms of heavy precipitation, even more intense? This is the underlying question in this study, in which the atmosphere and the ocean conditions in October 2018 are examined to identify anomalies favoring this intensification. Furthermore, the model representativity of the over-averaged precipitation period and underlying anomalies is analyzed across scales using climatological, seasonal, and event-based COSMO high-resolution model simulations.Our investigation shows that October-2018, in the context of the climatological series from 1982 to 2018, could be marked as an unprecedented period because of the presence of intense and numerous low-pressure systems. Additionally, atmospheric moisture values placed this time above the climatological average, mainly for the high percentiles of the TCWV hourly anomalies. Specific humidity showed similar behaviour as TCWV except for pressure levels lower than 700 hPa, probably in relation to the evolution of the former Hurricane Leslie. The atmosphere-ocean interaction presented combined strong sea surface temperature (SST) and evaporation anomalies. April to October SST clearly exceeds climatological values while October-2018 presents both strong monthly anomaly and intense evaporation peaks preceding the most intense precipitation events. These large-scale features’ anomalies were in general well captured by the high-resolution regional climate model simulations at climatic and seasonal scales leading to an accurate representation of accumulated precipitation for the October period. However, the numerical weather prediction simulations on an event scale revealed low predictability, in agreement with former investigations, due to differences at the location and intensity of the cut-off lows and particularly at the atmospheric moisture field.The conclusions of this study show that it is not the most extreme period in terms of single anomalies which lead to extreme wet seasons, but the synergy of atmospheric and oceanic anomaly conditions with a constant interplay which made Autumn/October 2018 an extreme season/month.

Nutrition value of dominant three fishes of Sudanese red sea coast

Based on the current demand on fish as food, marine fishes of the Sudan have been arbitrary divided into first, second and third grade fish. Examples of these are the red emperor (Plectroponus moculates) grade I, mullet fish (Plectroponus moculates) as grade II and unicorn fish (Naso unicornis) as grade III. This subjective grading, need to be evaluated on grounds of organo-leptic tests, gross chemical and body parts analysis and inclusion in experimentally designed feeding tests. The mean value and range of moisture, protein, fat and ash was determined and compared for the three species. The highest calorific value was (232.08) in C. crisbis and the lowest (144.2) in P. maculatus. The calorific value was expressed as a calories per percent of protein content plus calories per percent of fat content. The highest calorific value was (232.08) in C. crisbis and the lowest (144.2) in P. maculatus. The gross chemical composition was comparable between the three groups in ash content, but showed significant variability within moisture, within protein and in fat. The mean body weight in each cell in a column (feed 1, 2, 3 and the control) was based on a triplicate and they were compared using the least significant difference (LSD) test. Very highly significant growth correlation (p

How accurately can we retrieve irrigation timing and water amounts from (satellite) soil moisture?

While ensuring food security worldwide, irrigation is altering the water cycle and generating numerous environmental side effects. As detailed knowledge about the timing and the amounts of water used for irrigation over large areas is still lacking, remotely sensed soil moisture has proved potential to fill this gap. However, the spatial resolution and revisit time of current satellite products represent a major limitation to accurately estimating irrigation. This work aims to systematically quantify their impact on the retrieved irrigation information, hence assessing the value of satellite soil moisture for estimating irrigation timing and water amounts.

Development and Implementation of Smart Irigation for Precision Farming

The agricultural sector is one of the important sectors in people’s lives as well as an important role in Indonesia’s economic growth. However, agriculture in Indonesia is not a few who still use conventional technology, so an agricultural system that can make it easier for farmers to manage their agricultural land is needed. In this system, a smart irrigation system is developed which is implemented for precision farming, by utilizing IoT technology as a means of connection between devices as well as monitoring and controlling irrigation. Parameter values such as air humidity, air temperature, soil moisture, and soil pH measured on the sensor will be sent to the database server to be displayed on the front end of the website so that users can access them using their respective devices. In addition, the soil moisture value stored in the database will later be used by the solenoid controller component to carry out the watering process.

Spatial variability of soil moisture in a mining subsidence area of northwest China

The current study investigated the impact of coal mining on deep soil moisture from the perspective of the absolute value of soil moisture. A combined classical statistics and multi-dimensional geo-statistics approach was employed to analyze the temporal and spatial changes in soil moisture from 0 to 10 m in the mining face of the Nalin River No. 2 Mine in Northwest China from the perspective of spatial variability. The results of the study show that compared with the control area, the average value of soil moisture in 1- and 2-year subsidence areas decreased by 1.18% and 0.96%, respectively, whereas the coefficient of variation increased by 17.92% and 3.63%, respectively. Interpolation of soil moisture spatial distribution results showed that the spatial variability of soil moisture in the control area was less than that in the subsidence areas, and the spatial variability of soil moisture in the 2-year subsidence area was less than that in the 1-year subsidence area, indicating that mining increases the spatial variability of soil moisture and that the degree of spatial variability of soil moisture decreases as the subsidence enters the stable period. These results provide evidence for the mechanism by which coal mining subsidence affects soil moisture. Preferential flow caused by surface cracks, soil texture, the soil pore microstructure, and other factors in the coal mining subsidence area are the primary drivers of the increase in spatial variability of soil moisture.

Smart Greenhouse Monitoring With Soil Temperature and Humidity Control on Internet of Things (IoT) Based Orchid Plants

Research on monitoring systems with control has been developed with several different inputs and outputs. This research has realized a smart greenhouse monitoring tool with temperature and soil moisture control on orchid plants based on the Internet of Things (IoT). This study aims to create a monitoring tool for temperature, air humidity, soil moisture, and water level. In the system, the microcontroller used is Wemos D1 R1, with inputs in the form of a DHT-11 sensor to measure air temperature and humidity, a soil moisture sensor to measure soil moisture, and an ultrasonic sensor to measure the water level in the containers. The resulting system output is in the form of pump and fan control. Based on the results of sensor testing, the accuracy of the DHT-11 sensor is 99.97%, the error is 0.03%, the soil moisture sensor is 98.63% accurate, the error is 1.37%, and the ultrasonic sensor is 97, 61% with an error of 2.89%. Based on the research results, the system can run well, as shown by Thingspeak, and the website smartgreenhouseanggrek.weebly.com can receive the results of monitoring sensor data using an internet connection. The tool will carry out the process of wateringplants when the soil moisture value read by the sensor is 20% and will stop watering when the sensor reads the soil moisture value reaches >= 50%. In contrast, the air temperature control is done by turning on the fan if the temperature reaches 30° C.

Utilization of water extract of yellow potato (Solanum tuberosum L.) in hydrogel eye mask as anti-aging formulation

The thinness and sensitivity of the skin in the area under the eyes cause the skin in this area to easily show signs of aging. Hydrogel masks contain quite a lot of water, so during use this mask will moisturize the skin longer. A hydrogel eye mask containing yellow potato tuber water extract is used for the prevention of premature aging, especially under the eyes. The purpose of this study was to determine whether hydrogel eye mask preparations containing water extract of yellow potato tubers can provide an anti-aging effect. Material and methods: The yellow potato tuber water extract was screened for phytochemicals, then formulated into a hydrogel eye mask with a concentration of 0.25 %, 0.5 %, and 1 %. Evaluation of the hydrogel eye mask preparation includes organoleptic, weight, thickness, pH test, tensile test, swelling power, shrinkage, stability, cycling test, hedonic test, and anti-aging. Anti-aging parameters measured include moisture, pores, blemishes, and wrinkles. The treatment was carried out for four weeks by applying the mask twice a week. Results: The results showed that all hydrogel eye mask formulas were stable during storage and cycling tests. All formulas meet pH values, shrinkage, elasticity, swellability, and irritation tests. The hedonic test on volunteers shows the most preferred concentration of 1 %. The results of the anti-aging effectiveness test of the best hydrogel eye mask preparation is a concentration of 1 % with an increase in humidity of 27 %, a decrease in pores of 35.8 %, blemishes of 40 %, and wrinkles of 37.6 Conclusion: That the different concentrations of each formula showed different anti-aging activities and the best formula was 1 % with moisture values of 27 %, pore values of 35.8 %, blemishes of 40 %, and wrinkles values of 37.6 %, which indicated anti-aging activity

Production and Quality Evaluation of MASA Made From Maize, Rice and Millet Fortified With Soybean and Tigernut

This work was aimed to evaluate the quality of masa produced from rice, maize, millet fortified with soybean and tigernut. The proximate and sensory evaluation analyses were carried out on the masa samples for the whole grains and as well as the enriched masa samples. While functional properties were carried out on the flour produced. The result of the proximate composition showed that lowest moisture value (14.00%) was recorded for sample A among the enriched ‘masa’ samples while 12.75% was recorded for sample E among the whole samples which is good for shelf life stability. Sample C had the highest crude protein (7.87%), sample B had the highest fat content (32.03%), and sample A had the highest fibre (0.16%) and carbohydrate (57.56%). The bulk density, water absorption capacity, oil absorption capacity, swelling capacity and gelation concentration were within the range; 0.64-0.81g/ml, 123.33-180.57%, 93.57-142.21%, 47.67-125.33%, 0.20-0.60g respectively. The sensory evaluation showed that with regards to taste, texture, colour, appearance, aroma and overall acceptability sample B was more preferred among the enriched ‘masa’ samples and sample E was more preferred among the whole samples. Enrichment of ‘masa’ could contribute to improvement of nutritional status if promoted as a nutritious, health indigenous snack not only where ‘masa’ is already widely consumed, but also in other parts of Nigeria where it has not found wide acceptance.

The use of ultrasonic vibrations in an innovative freeze-drying apparatus equipped with physical screen

The article's authors examined the possibilities of intensifying the lyophilization process in an innovative sublimation device with the help of ultrasonic vibration. The introduction of lyophilization technology on an industrial scale began relatively recently. Manufacturers widely used this technology to process high-value food products, primarily berries, vegetables, and fruits. The purpose of freeze drying is to reduce the products' mass and preserve the product’s properties for a long time. Lyophilization involves the removal of water from the frozen product, sublimation, and desorption under high vacuum conditions. The process aims to obtain the desired residual moisture value in the final product. However, the process implementation is associated with large consumption of the required energy. The high energy costs and long time needed for lyophilization make it an expensive process compared to other drying technologies, especially in the case of freeze-drying fishery products. Therefore, the authors propose introducing ultrasonic vibrations to the product with the help of an advanced pin to create fine ice crystals inside target bodies and speed up the sublimation process without significantly impacting aesthetic properties.

Pistachio green hull extract as natural antioxidant incorporated to omega-3 rich kappa-carrageenan oleogel in dry fermented sausage

The purpose of this study was to investigate the effects of pistachio green hull extract (PGH) as natural antioxidant and preservative on the quality of ω3 rich fermented sausage. Samples were prepared by linseed oil gelled emulsion and treated with PGH-extract (LGE-PGH), with synthetic antioxidant (LGE-BHA), and without antioxidant (LGE-NON) and properties of them were studied during the ripening and storage for two months. The results showed that the moisture and aw values of LGE-PGH were higher than LGE-NON. Moreover, LGE-PGH had lower TBARS values and higher ω3 and polyunsaturated fatty acids (PUFA) values compared to LGE-NON. The PGH-extract also reduced L* and b*, increased a* and hue in fermented sausages. Thus, the PGH-extract can be used as a natural preservative of ω3 rich dry fermented sausages without causing undesirable effects on it.

EMANATION OF RADON-222 FROM DIFFERENT SOIL TYPES AND SOIL GROUPS

In this paper, we deal with measurement of 222Rn emanation coefficient (Ke) of soils using an accumulation method. We created a database of Ke values of dried soils for various soil types and soil groups, classified by the size of soil particles. For 18 different soil samples we obtained the Ke values in range 0.083-0.234. The analysis of radon emanation dependence on moisture for seven of these samples shows two different trends which were related to soil texture (clays or sands). Soils with predominant sandy particles prove weak dependence on moisture and Ke values from minimum value (at zero moisture) do not increase much (max 15% increase on every 5% of moisture), for soils with majority of clayey particles the moisture can affect the Ke more significantly (increase up to 60%).

Encapsulation of phenolic and antioxidant compounds from spent coffee grounds using spray-drying and freeze-drying and characterization of dried powders.

Spent coffee grounds (SCG) are a coproduct that causes environmental impacts worldwide. Thus, consciously reusing the SCG is an eminent need. This work aimed to encapsulate phenolic compounds and antioxidants obtained from SCG extracts through spray- and freeze-drying techniques using different isolated and combined wall materials. The dried powders produced were evaluated for moisture content, water activity, bulk density, hygroscopicity, color, content of phenolic compounds and antioxidants, and the results were compared. The results showed that all evaluated treatments resulted in a powdered product with low values of bulk density, moisture and water activity, especially for freeze-drying. The freeze-dried product also showed higher hygroscopicity. Regarding the content of phenolic compounds and antioxidants, both drying methods showed high levels of these compounds in the dried product and good encapsulation efficiency, reaching 83.43%. In most cases, spray-drying and freeze-drying did not differ statistically (p>0.05) in relation to bioactive compound content and encapsulation efficiency. In relation to wall materials, albumin showed the worst performance in the retention of bioactive compounds. On the other hand, pure gum arabic combined with maltodextrin led to better preservation of these compounds. PRACTICAL APPLICATION: Spent coffee grounds are a coproduct generated in large quantities in the world. The encapsulation of phenolic and antioxidant compounds protects and enables their application in different food matrices. Therefore, the evaluation of different encapsulation methods and wall materials is important to define good process conditions.

Hydrological influence on the variation of the terrestrial gravity field in Manaus, Amazonas, Brazil

The influence of groundwater on the hydrological cycle has been studied at large-scale across the Amazon Basin, one of the largest freshwater reservoirs in the world. Considering this Basin's importance in the global hydrological cycle, local studies also are critical. Here, we focus on the local hydrological cycle in Manaus, at the center of the Amazon Basin. We observed the variability of local gravity, fluvial height, soil moisture, precipitation, evapotranspiration and groundwater in the rainy (December–May) and dry (June–November) seasons, during drought (2016) and flood (2017) years. In general, in the beginning of the rainy season, soil moisture is instantaneously influenced by the first precipitation, increasing gravity. After, the soil becomes saturated and the variation in soil moisture achieves maximum values, which are sustained until the end of rainy season. After soil saturation by infiltration, the groundwater starts to be fed by percolation and the water table starts to rise. Thus, variation in local gravity reflects mainly variations in groundwater level. After the dry season starts, the soil loses moisture (soil moisture values decrease), while the gravity signal maintains high values, representing the sustained behavior of the groundwater. Modeling the vertical gravity component influenced by soil moisture and by groundwater results, respectively, in 49.63 nm/s2 and 314.70 nm/s2. In comparison with the gravity measurement of 368.02 nm/s2, we confirm that the groundwater is the main contributor to the gravity signal. We also find a strong correlation between fluvial height and the gravity signal, but demonstrate with 3D modeling that the Negro River height variation does not directly influence the gravity signal. Instead, we explain the similarity in fluvial height and the gravity signal by the connection between fluvial height and groundwater, and the correlation between groundwater and gravity variations.

Nutritional Assessment of Fermented and Roasted Tamarindus indica Seeds from Lapai, Nigeria

This work studied the proximate, mineral and phytochemical content of fermented and roasted Tamarind (Tamarindus indica) seed nuts, using standard analytical methods. The seeds were divided into two; one portion was roasted at temperature 85 - 100 oC for 15 mins while the second portion was fermented for 48 hours in the presence of yeast. The proximate analysis of the roasted and fermented samples revealed the values of moisture, ash, crude lipid, Crude protein, crude fibre, carbohydrate and calorific values of the fermented sample were 10.70±0.21 %, 3.06±0.71 %, 2.30±0.19 %, 19.25±0.16 %, 5.75±0.33 %, 58.94±0.23% and 301.29±0.31kcal/100g while values for the roasted sample were 2.00±0.82 %, 3.34±0.53 %, 7.60±0.43 %, 23.63±0.11 %, 5.22±0.74 %, 58.21±0.17 % and 329.08±0.92 kcal/100g respectively. Mineral elements present were K (336.75±0.31 mg/100g), Mg (166.90±0.37 mg/100g), P (106.42±0.65 mg/100g), Na (186.52±0.09 mg/100g) and Ca (10.33±0.15 mg/100g) for the fermented sample and values obtained for K, Mg, P, Na and Ca in roasted sample were 784.95±0.43, 187.65±0.17, 122.38±0.29, 54.36±0.13 and 12.65±0.11 mg/100g respectively. Results of phytochemical content showed that fermented Tamarindus indica contained tannin (64.61±0.43 mg/100 g), saponnins (127.33±0.79 mg/100 g), flavonoid (3.53±0.18 mg/100 g) and alkaloid (23.56±0.37 mg/100 g) while phytochemicals in the roasted sample were 40.97±0.21, 94.69±0.29, 1.96±0.51 and 14.33±0.12 mg/100g for tannins, saponins, flavonoid and alkaloids respectively, and were significantly lower than those in the fermented sample. Correlation analysis indicate a correlation exist between nutritional content of fermented and roasted samples of T. indica. The high crude protein, carbohydrate, calorific value and mineral content in fermented and roasted T. indica seeds indicate that the seeds could be good source of nutrient.

A Comparative Study on Microbiological and Chemical Characteristics of Small Ruminant Carcasses from Abattoirs in Greece.

Meat quality dictates consumer preferences with hygiene forming a key component, especially in meat types with declining popularity, such as sheep and goat meat. Aiming to increase the marketability of sheep and goat meat, we examined 370 sheep and goat carcasses from two abattoirs in Greece. Tests included enumeration of the total mesophilic viable count, total psychrophilic viable count and coliform count, and detection of Salmonella spp., Listeria monocytogenes and presumptive ESBL Escherichia coli. Moreover, designated samples of meat were used to measure pH, moisture, total fat and protein content. Goat carcasses had significantly higher microbial counts compared to sheep carcasses. Lamb and kid carcasses had larger TMVC, TPVC and coliform counts compared to carcasses from adult animals. One strain of L. monocytogenes (0.8%), typed as serovar 1/2a (3a), was isolated from one adult sheep carcass. Twelve strains of ESBL Escherichia coli (25%) were isolated; there were not any strains of Salmonella spp. The average values of pH, moisture, total fat and total protein were 5.83%, 67.76%, 7.21% and 21.31%, respectively, for sheep carcasses and 5.70%, 68.2%, 5.69% and 24.10%, respectively, for goat carcasses. The results showed a small deviation in assessed parameters, implying the uniformity of the conditions concerning rearing and slaughtering.

Investigating the nutritional profile and bacteriome diversity in Bangladeshi sour yogurt

Yogurt is an ethnic fermented food that dominates as an integral part of human diet for its health benefits. The nutritional quality of yogurt is diminished due to the presence of adulterants, metal and microbial contaminants. Upon consumption, these materials cause metabolic disorders and food-borne diseases. This study was designed to explore the physicochemical parameters, minerals, heavy metals, and bacteriome diversity in Bangladeshi sour yogurt prepared from cow and buffalo milk. Bacterial culture followed by 16S rRNA sequencing was performed to assess the bacterial consortia in yogurt. The higher amount of total solid (TS), solid-not-fat (SNF), pH, calcium and iron, and lower value of moisture, potassium and magnesium were observed at significant level (P < 0.05). Lactobacillus and other pathogenic bacteria like Shigella, Aeromonas, Enterobacter and Escherechia were isolated where Lactobacillus predominated. From amplicon sequencing, cow yogurt samples were observed to be predominated by Lactobacillus and Streptococcus while Enterobacter, Lactococcus, Aeromonas and Acinetobacter were the top abundant bacterial genera in buffalo yogurt. Crucial factors affecting the yogurt quality viz. nutritional profile, and bacterial community structure were explored for the first time in this study that will inevitably aid in the safe production of yogurt and public health measures globally.

Soil Moisture Mapping with Moisture-Related Indices, OPTRAM, and an Integrated Random Forest-OPTRAM Algorithm from Landsat 8 Images

Remote sensing tools have been extensively used for large-scale soil moisture (SM) mapping in recent years, using Landsat satellite images. Rainfall, soil clay percentage, and the standardized precipitation index play key roles in determining the moisture content of crop fields. The objective of this study was to (i) calculate and determine the effectiveness of moisture-related indices in predicting surface SM, (ii) predict surface SM from satellite images using the Optical Trapezoid Model (OPTRAM), and (iii) evaluate if the OPTRAM predictions can be improved by incorporating weather station, soil, and crop data with a random forest algorithm. The ENVI® platform was used to create moisture-related indices maps, and the Google Earth Engine (GEE) was used to prepare OPTRAM maps. The results showed a very weak relationship between the moisture-related indices and surface SM content where r2 and slopes were ˂0.10 and ˂0.20, respectively. OPTRAM SM, when compared with in situ surface moisture, showed weak relationship with regression values ˂0.2. Surface SM was then predicted using random forest regression using OPTRAM moisture values, rainfall, and the standardized precipitation index (SPI), and percent clay showed high goodness of fit (r2 = 0.69) and low root mean square error (RMSE = 0.053 m3 m−3).