Average Relative Air Humidity Research Articles

Comparative Analysis of Machine Learning-Based Predictive Models for Fine Dead Fuel Moisture of Subtropical Forest in China

The moisture content of fine dead surface fuel in forests is a crucial metric for assessing its combustibility and plays a pivotal role in the early warning, occurrence, and spread of forest fires. Accurate prediction of the moisture content of fine dead fuel on the forest surface is a critical challenge in forest fire management. Previous research on fine surface fuel moisture content has been mainly focused on coniferous forests in cold temperate zones, but there has been less attention given to understanding the fuel moisture dynamics in subtropical forests, which limits the development of regional forest fire warning models. Here, we consider the coupled influence of multiple meteorological, terrain, forest stand, and other characteristic factors on the fine dead fuel moisture content within the subtropical evergreen broadleaved forest region of southern China. The ability of five machine learning algorithms to predict the moisture content of fine dead fuel on the forest surface is assessed, and the key factors affecting the model accuracy are identified. Results show that when a single meteorological factor is used as a forecasting model, its forecasting accuracy is less than that of the combined model with multiple characteristic factors. However, the prediction accuracy of the model is improved after the addition of forest stand factors and terrain factors. The model prediction ability is the best for the combination of all feature factors including meteorology, forest stand, and terrain. The overall prediction accuracy of the model is ordered as follows: random forest > extreme gradient boosting > support vector machine > stepwise linear regression > k-nearest neighbor. Canopy density in forest stand factors, slope position and altitude in terrain factors, and average relative air humidity and light intensity in the previous 15 days are the key meteorological factors affecting the prediction accuracy of fuel moisture content. Our results provide scientific guidance and support for understanding the variability of forest surface fuel moisture content and improved regional forest fire warnings.

Innovative approach to diagnosing the development of net blotch in winter barley

The article demonstrates the possibility of applying intelligent digital technologies to forecast the development of net blotch disease in winter barley caused by Pyrenophora teres. The obtained intelligent solution in the form of a binary decision tree has the ability to determine scenarios of net blotch development into three classes: depressive, moderate, and epiphytotic. To effectively train the model during the period from 2021 to 2023, field and laboratory experiments were conducted on the research sites of the Federal Research Center of Biological Plant Protection. The experiments collected data on the degree of leaf damage, the type of resistance of the variety, the growth phase at which primary infection occurred, and the average relative air humidity during the vegetation period in which infection occurred. The total sample size was 249 observations. The trained model demonstrated high classification accuracy on both the training and test sets, with an accuracy rate exceeding 0.96 and 0.92, respectively. The study shows that the innovative method discussed in the article for forecasting the development of net blotch in winter barley can be successfully integrated into the overall strategy of phytosanitary diagnostics of grain crops, including barley.

Canopy Gaps Control Litter Decomposition and Nutrient Release in Subtropical Forests

The formation of a canopy gap results in changes to the microenvironment which, in turn, affect litter decomposition and nutrient release. However, the mechanisms underlying these effects in differently sized gaps and non-gaps remain poorly understood. To address this gap in knowledge, we selected three large gaps (above 150 m2), three medium gaps (50–100 m2), three small gaps (30–50 m2), and three non-gaps with basically the same site conditions. We then used the litter bag method to investigate leaf and branch litter decomposition over a year in a Castanopsis kawakamii natural forest with the aim of characterizing the litter mass remaining and the nutrient release in canopy gaps and non-gaps. Our results revealed that the remaining litter mass of leaf and branch litter was lower in medium gaps compared to other gaps, and leaf litter decomposed faster than branch litter. Environmental factors were identified as the primary drivers of total carbon and nitrogen release during litter decomposition. Gap size (canopy openness), taxonomic Margalef index, the Brillouin index of soil microbes, soil total nitrogen content, soil pH value, and average air temperature were identified as the main factors driving carbon and nitrogen release from branch litter. In the late decomposition stage, the taxonomic Pielou index, soil total potassium content, soil water content, and average relative air humidity were the main drivers of nutrient release from branch litter. The soil water content and average relative air humidity were also found to be the main factors affecting the nutrient release from leaf litter throughout the different stages of decomposition. Overall, our study highlights the impact of canopy gaps on microenvironmental variation, taxonomic community diversity, and soil microbial functional diversity and how these factors ultimately influence litter decomposition and nutrient release. Our findings provide an important foundation for further research into soil nutrient cycling in subtropical natural forests.

KARAKTERISTIK PENGERINGAN SAGU MENGGUNAKAN ALAT PENGERING TENAGA SURYA TIPE RAK1)

ABSTRACT
 
 This study aims to test the performance of a solar dryer for drying sago. Performance tests include: temperature distribution pattern, relative humidity of the air in the drying chamber, changes in moisture content, drying time, and drying rate. The benefits of this research are expected to use a rack-type solar dryer to shorten the drying time and also this tool can provide an overview of the use of solar energy in the process of drying sago and drying other crops. During the drying process there has been a temperature difference between the bottom shelf, middle shelf, top shelf, chimney and ambient air temperature. The average relative humidity of the ambient air on the first day is 63.75% with a maximum condition of 67% and the lowest air relative humidity condition is 60% and the average relative humidity of the air inside the device on the first day is 34.62% with a maximum condition of 37% and the lowest air relative humidity condition is 33%. The average relative humidity of the ambient air on the second day is 65.66% with a maximum condition of 69% and the lowest air relative humidity condition of 62% and the average relative humidity of the air insi de the device is 35.83% with a maximum condition of 38% and the lowest air relative humidity condition is 33%. The mathematical model of the relationship between water content and time on the bottom shelf is y = 0.6305e- 0.127x with R² = 0.972 on the middle shelf y = 0.6149e-0.118x with R² = 0.9875 on the top shelf y = 0.6434e-0.11x with R² = 0.9649. The drying rate on each shelf is different and changes occur every time because it depends on the mass of the material. The average drying rate on the lower shelf is 3.40%, the middle shelf is 3.31%, and the upper shelf is 3.21%. To reach a moisture content of 11-14% requires a total of 13 hours for 2 days.
 
 
 Keywoards : sago drying, rack tipe solar dryer

Estimating the relationship of sugarcane borer larvae and crop damage based on adult captures and climate variables

Sugarcane borer Diatraea saccharalis (F.) is the primary sugarcane pest in Brazil. To estimate the relationship between larvae in sugarcane stalks and captures of male adults of D. saccharalis, we collected samples weekly: (1) adults with one delta trap with three virgin females and three female pupae and (2) larvae in 120 stalks per plot of 12.6 hectares (355 × 355 m). The study was conducted in two sites with five plots each, in the municipalities of Nova Ponte and Tupaciguara, Minas Gerais State, Brazil, from July 2016 to May 2017. Relationships between (1) males trapped per week and the number of larvae outside of stalks (LOS) were estimated and (2) we evaluated climate variables, namely average temperature, average relative air humidity, hours with relative air humidity below 30 %, rainfall and number of rainy days, and adults and larvae of D. saccharalis. We obtained generalized linear models for LOS in autumn and for larvae inside the stalks (LIS) in spring and autumn and trapped males in both sites. A significant and direct relationship between LIS and males trapped allows predicting larvae density based on captures of males. In addition, plant damage can be estimated based on accumulated captures of males. There was a negative relationship between hours of air humidity < 30 % and larvae outside of stalks. Densities of LIS can be estimated from male captures and by the humidity variables in the trapping week. Nevertheless, the models require validation in the field.

A relationship between weather conditions and a number of forest fires

This work presents an approach to identifying the relationship between weather conditions in the region and a number of wild fires. On the basis on the official data, an assessment of meteorological conditions (average monthly air temperature, average monthly relative humidity, total precipitation, average wind speed) was carried out, and the hydrothermal coefficient was calculated for various areas of the Right-Bank and Left-Bank parts of the Saratov region. The obtained values are compared with the number of fires occurring in the selected territories: the study areas and parts of the Saratov region. It is shown that the best values of the correlation coefficients are observed when comparing data on the average relative air humidity and the number of fires. In some cases, a correlation is observed between the amount of precipitation and the average air temperature. Weather conditions are a combination of air temperature and relative humidity. Both of these parameters can be taken into account by calculating the hydrothermal coefficient, and its comparison with the number of fires may give a more accurate picture. Nevertheless, the calculation of the hydrothermal coefficient and the joint analysis of its values with the number of fires showed low values of the correlation coefficients. Nevertheless, if we combine the change in the values of the hydrothermal coefficient on the graph with the change in the number of forest fires, then it becomes clearly visible that there is a temporary shift in the period of occurrence of forest fires relative to the period of low level of moisture in the territory.

Spatial structure and motor activity of horses of Zabaikalsky breed

The total influence of external environmental factors by seasons on the spatial structure and motor activity of herd horses of Zabaikalsky breed with year-round grazing was studied. The scientific and economic research was carried out in Trans-Baikal Territory. Grazing of 10 herds of horses (20-27 heads) was carried out on the area of 301.5 km2 at different distances from each other. The distance from the horse-breeding camp was 2300-7900 m. According to the motor activity assessment of horses in the spring and summer seasons during 14 hours of grazing, the average speed was 1.4 and 1.1 km/h, the distance traveled was 16828 and 14827 m. The average air temperature during these periods was 10.4 and 12.2 °С, average air velocity was 4.5 and 2.1 m/s, average relative air humidity was 32.2 and 53.3%. In the autumn period, during 10 hours of grazing, the distance was 13879 ± 195.7 m at a horse speed of 1.2 ± 0.07 km/h, average air temperature of minus 1.1 °C, air speed of 2.3 m/s, and air humidity of 54.4%. In winter, the grazing time was 8 hours, the horses in the experiment covered the distance of 12190 ± 142.3 m at a speed of 1.8 ± 0.03 km/h with an average temperature of minus 24.7 °C, wind speed of 1.5 m/s and relative humidity of 64.7%. In the spring, the horses covered the distance greater than in summer, by 13.5% (p &lt; 0.01), in autumn - by 21.2% (p &lt; 0.001) and in winter - by 38.0% (p &lt; 0.001). The highest nutritional value of pasture herbage was noted in the summer (0.60 feed units/kg of dry weight, 102.3 g of digestible protein/ feed unit). In the spring, the nutritional value of pasture grass was 0.35 feed units/kg of dry weight with 31.5 g of digestible protein.

Egg quality and endoparasite prevalence in free range chicken farming in Apodi and Mossoró, Rio Grande do Norte, Brazil

The objective of this work was to assess the production quality of free-range eggs in the municipalities of Apodi and Mossoró, in the state of Rio Grande do Norte, Brazil. The microbiological and physical quality of the eggs and the endoparasite prevalence in the chickens were used as parameters. The egg microbiological evaluation consisted of the detection and quantification of total and thermotolerant coliforms, mesophilic bacteria, Staphylococcus aureus, and Salmonella sp. The eggs were classified according to their weight, yolk color, yolk pH, albumen pH, Haugh unit, yolk index, and shell thickness. The parasitological analyses consisted of collection of fresh excreta and application of the spontaneous sedimentation technique by the Hoffmann method and the Faust flotation method to identify the parasites. All egg samples were negative for total and thermotolerant coliforms, mesophilic bacteria, and Salmonella sp. Regarding the physical quality, the eggs presented good yolk pigmentation and good internal and external quality. Regarding the parasitic load of the chickens, the presence of Eimeria sp. and Heterakis sp. was significantly higher in months with average precipitation greater than 100 mm; and in months with average relative air humidity above 80%, there was prevalence of Ascaris sp. parasites.

Bad moon rising? The influence of the lunar cycle on amphibian roadkills

Annually, roads, and their associated users, are responsible for millions of roadkills worldwide. Mortality affects multiple taxonomic groups, but amphibians are particularly vulnerable, due to their size and underreporting. In fact, very high mortality frequencies can occur, mostly during short periods of time, when individuals migrate to and from reproduction areas (e.g., ponds). In this study, we assess the influence of the lunar cycle on amphibian roadkills, while accounting for weather conditions. As expected, the main environmental effects explaining roadkill numbers were weather related, with increases in minimum air temperature, average relative air humidity, and cumulative rainfall during the previous 24 h having a positive effect on roadkill numbers for all studied species. However, the lunar cycle also affected roadkills for two of the studied species. Darker nights had higher numbers of roadkills of Pleurodeles waltl, while moonlit nights had higher numbers of Salamandra salamandra. As such, these moon effects are species specific. Animals that are more active in moonlight may be at an advantage if their visual acuity is better than that of their predators. We hypothesize that differences between species in the response to moonlight may be due to differences perceived in predation risk. This information should be considered when designing mitigation measures. Volunteer actions, for instance, can be planned and coordinated keeping in mind the most appropriate weather conditions for the general amphibian community and specific phases of the lunar cycle for particular species.

ВИЗНАЧЕННЯ КОРЕЛЯЦІЙНОГО ЗВ’ЯЗКУ МІЖ ОКРЕМИМИ МЕТЕОРОЛОГІЧНИМИ ВЕЛИЧИНАМИ У ДАТИ ПОЧАТКУ ВІДКЛАДЕННЯ ОЖЕЛЕДІ НА ТЕРИТОРІЇ УКРАЇНИ ПО МІСЯЦЯХ ХОЛОДНОГО ПЕРІОДУ РОКУ ПРОТЯГОМ 2001-2013 рр. ТА ЇХ ПРОСТОРОВИЙ РОЗПОДІЛ

The article presents the results of the study of the determination of the correlation connection between a number of meteorological values at the beginning of the deposition of ice on the wires of a standard ice-cream machine in certain months of the cold period of the year on the territory of Ukraine during 2001-2013. The research was conducted for 3 winter months, as well as for March and November. The pair of meteorological parameters have been determined at the beginning of the deposition of ice that have a statistically significant correlation coefficient and a spatial-temporal distribution of the distribution in certain months across the territory of Ukraine has been obtained. The most common variant of the statistically significant connection between individual meteorological parameters was the connection between the temperature of the water column (average, maximum, minimum) and relative humidity of air (average, maximum). Thus, for almost all months studied, a statistically significant correlation between the temperature of the vapor (average, maximum, minimum) and relative humidity of air (average, maximum) was established. For the winter months, the correlation coefficient of this connection was positive, and for March and November, it was negative. A widespread version of a statistically significant connection was the relationship between the air temperature (average, maximum, minimum) and the height of the snow cover. This connection for the months studied turned out to be negative. The variants of negative statistically significant connection between average wind speed and average relative humidity of air (January-February, December), average and maximum wind speed and sea-level pressure (November), and also between daily amount precipitation and snow (March), daily rainfall and wind speed (average, maximum), and pressure at sea level (November). During the months of the cold period of the year, statistically significant connections between the air temperature (average, maximum) and pressure at sea level (November), wind speed (average, maximum) and average humidity (January, December), pressure on sea levels and average relative humidity (March). Also, there were isolated cases of statistically significant correlation between snow and sea level pressure (December). The most frequently statistically significant connections between meteorological values at the dates of deposition of ice on the wires of a standard icing machine were observed at stations in the central, northeastern, eastern and separate southern regions.

Batch drying of sliced tomatoes at specific ambient conditions

Abstract In this work, drying of tomato slices was studied in a laboratory scale batch dryer working at conditions specific for geographical locations with low ambient pressure and low relative humidity of air. Tomato is a perishable farm product with high moisture content. Despite their high value, tomatoes are subjected to wastage and spoilage during their seasonal period; to last longer after harvested, they need to be treated by drying. Drying is one of the most widely used methods of tomato preserving for a longer period of time. This study involves experimental work on tomatoes drying in a tray laboratory batch dryer with the dimensions of (490 × 330 × 310) mm, a load cell-force sensor (range: 0–5 kg), fan (speed: 0–2500 rpm), air flow sensor (0–150 l/min) and a temperature and humidity monitoring system. This study was aimed at the development of a suitable drying method for the production of dehydrated agricultural products under specific air properties and climate conditions such as low ambient pressure and low relative humidity. During the experiment, the average ambient pressure was 82 kPa, and the average relative humidity of air was 20 %. Drying characteristics of tomato slices were determined at three temperature levels, namely: 50 °C, 60 °C and 70 °C,and three air flow rates: 30 l/s, 40 l/s and 50 l/s, for each temperature level. In this study, the effect of temperature, air flow rate, and ambient conditions on the drying rate of tomato slices were studied. The results indicate that during the experiments, tomatoes were dried to the final moisture content of 32.2 % from 92 %. Drying time at 50 °C, 60 °C and 70°C, and air flow of 30 l/s was 17.80 h, 15.80 h, and 14.08 h, respectively. For the air flow rate of 40 l/s, the drying time was 15.0 h, 12.9 h and 11.7 h and for the air flow rate of 50 l/s, the drying time of tomato slices was 14.0 h, 11.6 h and 10.2 h, respectively.

Seasonal Influences on Parasite Community Structure ofTurdus rufiventris(Aves)

Seasonality has strong effects on natural systems by influencing resource availability, thereby interfering in plant-herbivore, prey-predator, and host-parasite interactions. We compared the seasonal structure of the helminth community of rufous-bellied thrushes (Turdus rufiventris), assessed its correlation with environmental variables, and interpreted temporal patterns of parasite abundance in relation to their life cycles and likely changes in the availability of intermediate hosts and vectors. Fifteen helminth species were found in a sample of 151 thrushes collected on a seasonal basis over 3 yr. Infracommunity structure was affected by season and year. The ordination of component communities grouped fall and winter samples within a gradient of similarity that was correlated with average relative air humidity (RH) and average ambient temperature. RH (alone or in combination with temperature, rainfall, or both) was also found to be a good predictor of the abundance of 5 helminth species.

Crescimento da alface americana em função dos ambientes, épocas e graus-dias

This research was conducted in a protected (AE) and a natural environment (AN), and aimed to evaluate the development and to quantify the effect of the meteorological elements and degree-days&nbsp;on the growth of the lettuce crop in two different seasons. The research was conducted at the ";;Empresa Estadual de Pesquisa Agropecu&aacute;ria da Para&iacute;ba";; - EMEPA, during the periods of 30/05 to 08/08/2007 (Winter) and 10/09 to 22/11/2007 (Spring) using cabbage lettuce ";;Irene";;. Average air temperatures in AE were higher than the temperatures in AN, for both experiments. Values of the average relative humidity of air obtained in AN were always higher than AE. The higher values of degree-days in AE resulted in the reduction of the crop cycle and the total dry phytomass of the lettuce. The protected environment had a micro-climate favorable to the crop growth, anticipating the harvest of the lettuce by a week, in the two cultivation seasons, and the winter offered the best energy conditions for the growth and development of this cultivar.

Estimation of daily soil water evaporation using an artificial neural network

In field water balance studies, one of the major difficulties is the separation of evapo-transpiration into plant transpiration and soil evaporation. In this paper, the radial basis function (RBF) neural network was implemented using C language to estimate daily soil water evaporation from average relative air humidity, air temperature, wind speed and soil water content in a cactus field study. The RBF neural network learned rapidly and converged after about 1000 training iterations. The optimum number of hidden neurons was found to be six. The RBF neural network achieved good agreement between predicted and measured values. The average absolute percent error and the root mean squared error was 21·0% and 0·17 mm for the RBF neural networkvs. 30·1% and 0·28 mm for the multiple linear regression (MLR). The RBF neural network technique appears to be an improvement over the MLR technique for estimating soil evaporation.