Equatorial Climate Research Articles

IoT Monitoring System for Fig in Greenhouse Plantation

Fig is rich in nutrients and has a high market value due to its extensive application in promoting a nutritious food supply and supporting various medical disciplines. However, the equatorial climate in Malaysia poses significant difficulties for the large-scale cultivation of figs. Therefore, a Smart Monitoring System for controlled Greenhouse Plantation was proposed in this study to enable more efficient cultivation. The proposed system was equipped with LoRa and GSM to overcome the distance and data transmission limitations, developed using the Arduino Uno microcontroller. The proposed system consists of sensors to measure soil moisture, temperature, and humidity, while the data is transmitted using long-range LoRa communication to the control unit. The sensors circuit also has a solar power supply for convenient application in rural areas. The control unit is placed at a location with good data coverage. The system functioned well, and the monitoring parameter was accurately read, collected, and updated every 30 minutes. The optimal temperature, humidity, and soil moisture for growing fig is 22°C - 33°C, > 60%, and 50% - 60%, respectively. Real-time data monitoring enabled the sensors and control unit to achieve LoRa data transmission over a distance of 2.5 km. Any data exceeding the controlled parameters will trigger an alarm so that the user can perform corrective actions.

Case Study of Stormwater Control by Permeable Road in Commercial Centre under Equatorial Climate

This paper describes the investigation into stormwater control measures of a 3,425 m2 commercial centre with 61% of the total areas which were tarred surfaces. Targeting these surfaces, permeable roads of various surface areas from 10 to 34% of the total areas were modelled using Storm Water Management Model version 5.0. Testing the permeable roads for very-short duration storms ranging from 5 to 15 minutes, the study found that the catchment area contributing water for detention purposes played a major role in stormwater control. Other than that, the orifice outlet attached to the storage facility was dominant in determining the flow than the storage depth.

Photovoltaic assessment to achieve energy neutral buildings and cities in equatorial Andean climate

Energy is an important issue in the entire world and in under-development countries especially in these regions is where the main growth of energy requirements is expected. For more than fifty years ago Ecuador has been subsidizing fuels, considering that energy prices do have a huge impact on lowincome families. Cities and buildings do play a relevant role in reducing energy requirements to import energy to urban areas in order to achieve the maximum energy self-supply capability in buildings and cities. This study describes shortly recent works performed in Cuenca to decipher the energy resources available and the capability to self-supply in Cuenca, Ecuador. The main results obtained show that photovoltaics (PV) in buildings is the best option, it could supply the entire power requirements in the city, and around 22 % of the electrical requirements of industrial high-consumption buildings, also for a single-family home it is only required around 7 m2 of roof that corresponds around 10 % of a typical roof availability of a typical 2-floor house, and for higher education building it is possible to achieve the total power requirement with PV technology, but grid limitations imply limitations also to PV capability.

A comparative study on single and multiple trait selections of equatorial grown maize hybrids

Maize (Zea mays L.) production in tropical equatorial regions faces significant challenges due to agroclimatic and soil fertility variability, necessitating the evaluation of maize hybrid adaptability and phenotypic stability across diverse agroecosystems. This study compares the effectiveness of the additive main effects and multiplicative interaction (AMMI) and multi-trait genotype-ideotype distance (MGIDI) models for identifying superior maize hybrids well-suited to the equatorial climate. Fifteen genotypes, including 13 hybrid candidates and two popular commercial varieties (BISI 2 and NASA 29), were analyzed in 10 distinct environments in Indonesia over three consecutive years (2018–2020). The ANOVA method used in the AMMI model analyzed variance into three major components, with PCA analysis indicating that environments (E), genotypes (G), and their interaction (G × E) had a highly significant effect on yield (p < 0.001). Two hybrids, HM04 (CI301032/G102612) and HM02 (CI272022/G102612), displayed high adaptability and stability across various environments, with significantly higher yields than the grand mean by AMMI analysis. Additionally, HM10 (MAL03/CLYN231) and HM09 (G102612/CLYN231) were narrowly adapted to the ME-1 and ME-2 mega-environments, indicating they are best suited for these specific environments. Similar to AMMI, the MGIDI model suggested HM04 (MGIDI index = 1.74) and HM02 (MGIDI index = 1.76) as the two highest-performing hybrids, determined by their yield and nine other traits. Using the multiple trait combination index as a tool to assess the performance of these hybrids enabled researchers to determine the most effective traits for each genotype. The two models are recommended and may be integrated for comprehensive data interaction analysis, which simplifies the process of delineating genotypes with the environment and enables stakeholders to select desired traits while considering their strengths and weaknesses.

Early Cretaceous lepidosaur (sphenodontian?) burrows

Scarce fossil tetrapod burrows have been recorded in Cretaceous rocks, which is probably linked to the dominant equable climates that existed for most of this period. The occurrence of Cretaceous tetrapod burrows from Patagonia (Chubut Province, Argentina) dated between 118 and 115 million years ago, gives insights into their paleoecology and paleoenvironment. The rocks containing the tetrapod burrows are of pyroclastic origin and represent eolian dunes and ash-fall deposits, some reworked by fluvial currents and others showing soil development. Fossil burrow casts preserved in a paleosol are composed by a ramp with a slightly curved or straight path in plan-view and lacking bifurcation, a rounded termination with no enlargement, showing a reniform cross-section, and are assigned to the ichnospecies Reniformichnus katikatii. The strongly flattened cross-sectional shape of the burrow casts and comparison with modern lizard burrows suggest that the producers were lepidosaurs (body mass = 50–323 g). Among Cretaceous fossorial lepidosaurs from Patagonia, the best candidate is an eilenodontine sphenodontian. Sphenodontians burrowed in the fossil soils where also arthropods, earthworms and shrubby plants thrived. The rare occurrence of tetrapod burrows in Cretaceous rocks is linked to stressing conditions related to frequent arrival of volcanic ash and a semiarid seasonal climate.

Prevalence and predictors of chronic kidney disease of undetermined causes (CKDu) in Western Kenya’s “sugar belt”: a cross-sectional study

BackgroundEpidemics of chronic kidney disease of undetermined causes (CKDu) among young male agricultural workers have been observed in many tropical regions. Western Kenya has similar climatic and occupational characteristics as many of those areas. The study objectives were to characterize prevalence and predictors of CKDu, such as, HIV, a known cause of CKD, in a sugarcane growing region of Kenya; and to estimate prevalence of CKDu across occupational categories and evaluate if physically demanding work or sugarcane work are associated with reduced eGFR.MethodsThe Disadvantaged Populations eGFR Epidemiology Study (DEGREE) protocol was followed in a cross-sectional study conducted in Kisumu County, Western Kenya. Multivariate logistic regression was performed to identify predictors of reduced eGFR.ResultsAmong 782 adults the prevalence of eGFR < 90 was 9.85%. Among the 612 participants without diabetes, hypertension, and heavy proteinuria the prevalence of eGFR < 90 was 8.99% (95%CI 6.8%, 11.5%) and 0.33% (95%CI 0.04%, 1.2%) had eGFR < 60. Among the 508 participants without known risk factors for reduced eGFR (including HIV), the prevalence of eGFR < 90 was 5.12% (95%CI 3.4%, 7.4%); none had eGFR < 60. Significant risk factors for reduced eGFR were sublocation, age, body mass index, and HIV. No association was found between reduced eGFR and work in the sugarcane industry, as a cane cutter, or in physically demanding occupations.ConclusionCKDu is not a common public health problem in this population, and possibly this region. We recommend that future studies should consider HIV to be a known cause of reduced eGFR. Factors other than equatorial climate and work in agriculture may be important determinants of CKDu epidemics.

One Health Approach to Arbovirus Control in Africa: Interests, Challenges, and Difficulties.

The "One Health" concept considers that human and animal health, and ecosystems are closely related and aims to make a link between ecology and human and veterinary medicine. Due to the explosion in population growth along with the geographic and climatic conditions (equatorial and/or tropical climate), Africa is becoming a major hotspot for various socio-health issues associated with infectious diseases, including arboviruses. The incontestable advantages of a One Health approach in Africa lie in the fight against pathogens, such as arboviruses, and in the preservation of environmental, animal, and human health to ensure that the increasing high needs of this population are met as well as their protection against potential epidemics. The One Health strategy gives us a glimpse of the difficulties and challenges that the African continent faces. The importance of this approach in Africa is to establish guidelines and strategies for effective solutions and changes in behavior and harmful activities. Overall, the establishment of high-quality global health policies in the framework of the global health standards program would provide healthy and sustainable human-animal-environmental interactions for the welfare of all.

Sensitivity of solar panel energy conversion at sunrise and sunset on three weather fluctuations in equatorial climate

&lt;span lang="EN-US"&gt;The high sunlight intensity in tropical and equatorial regions makes the potential for installing photovoltaic (PV) panels. However, the initial design of PV installations must be analyzed. Their implementation is carried out in buildings with load power for household electricity scale. For this reason, the panel reliability system could be efficient by designing the initial PV requirements using systematic measurements. Collecting data on fluctuating sunlight intensity (unpredictable weather) conditions needs the use of manual measuring tools, namely digital light meters and PV data with sensor integration. The research sample consists of three fluctuating hot weather conditions, namely hot-sunny, hot-cloudy and hot-rainy conditions. These weather conditions were taken because the climate of West Sumatra tends to shift clouds which sometimes cover the sun's rays. The peak PV output for direct current (DC) power generated during hot- sunny conditions reaches 1827.17 W, in sunny-cloudy weather it reaches around 1626.85 W and during sunny-rainy weather conditions the resulting output is 1161.81 W. From daily measurements, the results show that the efficiency of the PV system is strongly influenced by the prevailing weather climate.&lt;/span&gt;

Clarification of the Lopingian palaeoclimatic conditions of the northwestern coastal regions of Palaeotethys based on the Transdanubian geological record

The Lopingian sedimentary rocks of South and South-Central Europe play an important role in reconstructing the same-age equatorial climate of the Pangea. However, geological evidence suggests a mismatch between the previously supposed equatorial monsoonal, tropical summer wet climate and the more arid Lopingian climatic conditions. To clarify the Lopingian climate of the northwest coastal region of the Palaeotethys, palynofloral assemblages and the climatic background behind the occurrence of soil, aridity, biome, and vegetation patterns of present-day arid and semi-arid territories were studied. In contrast to the similar lithological characters and the proposed Lopingian geographical proximity of the Southern Alpine and Transdanubian sequences, notable differences exist between the palynofloras of these regions. While the conifer-dominated, low-diversity Transdanubian flora belonged to the tropical, the more diverse Southern Alpine flora was part of the Permian Euramerican floral kingdom. Based on the occurrence of modern conifers, it is not plausible that Permian ones occupied arid regions. However, the current distribution of juvenile anhydrite, gypsisols and calcisols shows that the similar palaeosoils of the South Alpine and Transdanubian formations were formed in a tropical desert biome. By synthesizing the evidence exhibited above, it can be concluded that arid and semi-arid environments existed along the northwestern margin of the Palaeotethys and the humid, monsoonal regions were restricted to the Hercynian ranges. Local hydrological conditions plausibly had a notable impact on the occurrence of plant taxa in semi-arid regions which can explain the differences in the palynoflora despite the similar palaeoclimates.

Correlation between Photovoltaic Energy Production and Certain Climate Parameters: Case Study in the Plateau Department in Southern Benin

The Plateau department, where the first 25 MWp grid-connected solar plant was installed, is also an industrial cement zone, with high-energy demand, located in the south of Benin. In this region, the equatorial climate oscillated between two dry and two rainy seasons, with a high relative humidity. This climate variability influences the electrical output of photovoltaic (PV) modules. The analysis of the impact of climatic parameters such as relative humidity, precipitation, wind speed, ambient temperature, sunshine, on the photovoltaic production becomes necessary to optimize the energy generation in such a region. The objective of this study is to quantify the dependency relationship that exists between the variability of these parameters and the PV power generation using Pearson correlation method. The daily data collected for each parameter during the period from January 2011 to December 2020 were processed with Python 3.7.10 language. The results showed that relative humidity, with an average value of 80.14%, is the climatic has the highest negative impact (correlation coefficient of -0.42) on the performance of PV modules. Thus, the design and operation of a PV plant in this area should consider this parameter, especially with dust deposits, to improve the production yield.

Disentangling the mechanisms of equatorial Pacific climate change.

Most state-of-art models project a reduced equatorial Pacific east-west temperature gradient and a weakened Walker circulation under global warming. However, the causes of this robust projection remain elusive. Here, we devise a series of slab ocean model experiments to diagnostically decompose the global warming response into the contributions from the direct carbon dioxide (CO2) forcing, sea ice changes, and regional ocean heat uptake. The CO2 forcing dominates the Walker circulation slowdown through enhancing the tropical tropospheric stability. Antarctic sea ice changes and local ocean heat release are the dominant drivers for reduced zonal temperature gradient over the equatorial Pacific, while the Southern Ocean heat uptake opposes this change. Corroborating our model experiments, multimodel analysis shows that the models with greater Southern Ocean heat uptake exhibit less reduction in the temperature gradient and less weakening of the Walker circulation. Therefore, constraining the tropical Pacific projection requires a better insight into Southern Ocean processes.

Effects of Climate Change on Economic Growth: A Perspective of the Heterogeneous Climate Regions in Africa

Climate change is a negative global externality that threatens economic growth. In our study, we firstly reviewed the transmission mechanisms of climate change affecting economic growth based on existing literature. Secondly, we respectively used the fixed effect method and the panel vector autoregression method to test the short-run and long-run effects of climate change on the economic growth of 44 countries in six climatic zones in Africa, from 2000 to 2019. The results showed that temperature has inverted U-shaped effects on the economic growth of countries in tropical rainforest and tropical dry climate zones, but a U-shaped effect in warm temperate humid regions. The heterogeneity test was based on industrial and geographical perspectives. Climate change has a significant inverted U-shaped effect on agricultural and services output in tropical rainforest and tropical dry climate zones. Moreover, climate change positively impacts economic growth in coastal regions, but has no significant impact on inland countries. Lastly, the long-run results indicate that tropical rainforest and subtropical humid regions show a greater ability to adapt to climate change, while tropical desert regions show greater volatility resilience in response to climate change.

Influence of green roof systems on the energy performance of buildings and their surroundings

The thermal behavior of green roofs may vary according to climate and substrate and plant characteristics. This study aimed to analyze the influence of green roof systems on the energy performance of buildings and their surroundings under three different Brazilian climates. For this, 1944 combinations of green roof parameters were simulated. An initial validation of the thermal balance model was performed reaching RMSE of 2.17 °C and 2.85 °C, for substrate and vegetation temperature, respectively. It was obtained that, in temperate climate, low leaf area index (LAI), combined with high substrate thickness and low thermal transmittance, provided 5.6% of reduction with climatization when compared with cool roofs, and high transfer of latent heat to the exterior. In semi-humid tropical climate, 4.9% of savings was achieved with high LAI, intermediate substrate thickness, and high thermal transmittance. In equatorial climate, although there was high transfer of humidity, green roofs resulted in higher energy consumption than cool roofs, indicating that low thermal mass systems are more favorable for climates with low temperature fluctuations. The results showed that green roofs play a fundamental role in improving energy efficiency and outdoor air quality. However, an inadequate system may produce detrimental effects depending on climatic conditions.

Thermal tolerances of different life stages, sexes, and species of widow spiders (Araneae: Theridiidae)

Temperature strongly shapes the physiology and distributions of ectotherms. Environmental extremes and the range of temperatures encountered can limit persistence. Further, thermal tolerance limits are thought to be one of the factors limiting the distributions of invasive species. The critical thermal maximum (CTMax) and critical thermal minimum (CTMin) are metrics frequently applied for defining upper and lower thermal tolerances, respectively. Temperatures contained within the boundaries of the CTMax and CTMin comprise the thermal tolerance range. In this study, we tested whether thermal tolerances differed between two native (Latrodectus hesperus Chamberlin & Ivie, 1935 and L. mactans (Fabricius, 1775)) and one invasive (L. geometricus CL Koch, 1841) widow species (Latrodectus Walckenaer, 1805). We separately tested if thermal tolerances differed by life stage and sex. Using species distribution modelling, we also tested if thermal extremes or temperature range most accurately correspond with current species occurrences in the United States. We hypothesized that Latrodectus geometricus would have lower thermal tolerance range and that minimum temperatures would most influence their present distributions since they presumably originated from a more equatorial climate. We found that CTMin did not vary by developmental stage, but was highest in males. We found that the CTMin and CTMax of L. geometricus (3.2, 51.5 °C) and L. mactans (1.9, 52.4 °C) were higher than L. hesperus (-1.9, 49.6 °C). Males also had the narrowest thermal tolerance range in the three species examined. Lastly, we found that the highest performing distribution model was the one correlating minimum temperature with L. geometricus occurrences.

The rising impact of urbanization-caused CO2 emissions on terrestrial vegetation

Vegetation photosynthesis is largely determined by CO2 concentrations, which have significantly accumulated by urbanization. Thus, quantifying urbanization-caused CO2 concentrations’ impact on the terrestrial ecosystem, especially for vegetation photosynthesis (represented by GPP, NPP, NEP, and SIF), is vital. In this study, we firstly examined the effectiveness of the observation minus reanalysis (OMR) method in quantifying urbanization-caused CO2 concentrations and the effect of urbanization on CO2 accumulation from 2009 to 2018. Then, the effect of urbanization-caused CO2 on global vegetation GPP, NPP, NEP, and SIF was calculated and analyzed using terrestrial vegetation radiative transfer and prognostic models. Lastly, the impacts of urbanization-caused CO2 increase in different continents and vegetation types were analyzed, separately. The results demonstrated that: 1) Urbanization-caused CO2 concentrations accumulated for 3.93 ppm during 2009–2018. For carbon fluxes, urbanization-caused GPP, NPP and NEP accumulation increased 1.24 PgC, 0.64 PgC, 0.17 PgC, respectively, while urbanization-caused SIF accumulated 0.07 PWum−1sr−1. 2) From a continental perspective, South America accounted for the most significant urbanization caused GPP, NPP, NEP, and SIF accumulation, because the tropical rainforest climate dramatically assists photosynthesis in Amazon Rainforests. 3) Forests accounted for the most significant urbanization-caused GPP, NPP, NEP, and SIF accumulation (over 35% of global vegetation). 4) SIF is more sensitive to the autumn postponement of photosynthetic activities than GPP, NPP, and NEP. ΔOMR(GPP), ΔOMR(NPP), ΔOMR(NEP) showed the most significant urbanization impact in summertime, but the North Hemisphere’s photosynthesis accumulated dramatically in autumntime shown as rising ΔSIF_OMR, partly due to the delay of the end of the growing season which happens in most northern ecosystems. Thus, this study will be helpful for us to further understand the terrestrial carbon cycle dynamics and the potential for alleviating global climate change.

Coloured concrete produced from low-carbon cements: Mechanical properties, chromatic stability and sustainability

The global construction industry is responsible for 39% of CO2 emissions and for more than 50% of the extracted natural resources. Dematerialization and the use of low-carbon materials would be mitigating actions in the current scenario. In developing countries, where the housing deficit is high, a short-term and novel solution could come from the construction of social housing using multipurpose coloured concrete casings, which have no rendering of mortars and paints and are produced from low-carbon cements. In the Amazon, the wide availability of light and kaolinite-rich waste would enable the production of low-carbon cements (LCC) from ternary mixtures of clinker, calcined kaolin waste and limestone. The objective was evaluated the performance of coloured concretes from LCC against the weathering of the rainy equatorial climate of the Amazon, environment which favours the formation of biofilm films, impairing the aesthetic quality of the facades. The LCC provided coloured concretes with good pigmentation capacity and a significant reduction in CO2 emissions. On the other hand, its use compromised the surface quality of concrete due to the low chromatic stability. The climate conditions of the Amazon and low alkalinity of the LCC favoured the growth of microorganisms, leading the concrete surfaces to become prematurely blackened, decreasing their albedo and, consequently, raising the surface temperature of the substrate, which compromises the thermos-energetic performance of the building. Nevertheless, the results are promising and justify the continuity of research using new compositions of limestone calcined clay cement associated with the use of more efficient surface protection systems.

Forecasting of Rainfall across River Basins Using Soft Computing Techniques: The Case Study of the Upper Brahmani Basin (India)

Floods are potential natural disasters that might disrupt human activities, resulting in severe losses of life and property in a region. Excessive rainfall is one of the reasons for flooding, especially in the downstream areas of a catchment. Because of their complexity, understanding and forecasting rainfalls are challenging. This paper aims to apply the Adaptive Neuro-Fuzzy Inference System (ANFIS) in predicting average monthly rainfalls by considering several surface weather parameters as predictors. The Upper Brahmani Basin, which extends over 17,504 km2, was considered as a study area. Therefore, an ANFIS model was developed to forecast rainfalls using 37 years of climate data from 1983 to 2020. A hybrid model with six membership functions provided the best forecast for the area under study. The suggested method blends neural network learning capabilities with transparent language representations of fuzzy systems; 75% of data (from 1983 to 2006) was set aside for training and 25% (from 2006 to 2020) for testing. The Gaussian membership function with the hybrid algorithm provided satisfactory accuracy with R-values for training and testing equal to 0.90 and 0.87, respectively. Therefore, a new promising forecasting model was developed for the period from 2021 to 2030. The highest rainfall was forecasted for the period June–August, which is a striking characteristic of the monsoon climate. The study area is relatively close to the equatorial warm climate region. Hence, the proposed model might be of consistent use for regions lying in similar latitudes.

COMPARISON OF MEASURED SLANT PATH ATTENUATION AT 10.982 GHZ WITH LARGE-SCALE PREDICTION MODELS IN A TROPICAL CLIMATE

Rain-induced attenuation above 10 GHz can be severe at heavy rain rates resulting in deep fading, which can negatively impact the quality of receive signal level at the Earth station receiver. The dearth of direct measurement data in most of the tropical and equatorial climates has motivated the campaign for collection of rain attenuation data on slant paths in these regions. This is mainly due to a huge receiver margin required for such measurement, and which is very difficult to obtain by using a spectrum analyzer. The measurement results of rain rates and rain-induced attenuation in vertically polarized signals propagating at 10.982 GHz in a tropical Malaysian climate are presented in this study. The measured attenuation is compared with large-scale prediction models. As shown in the statistically-tested results, the Bryant model yields the best overall fit, while the Crane model yields the worst overall fit. The results show that the models have relatively good prediction capabilities in the Malaysian tropical climate; however, their prediction errors still need to be minimized. Therefore, in this study, a correction factor is proposed to enhance their predictions.

A Walker switch mechanism driving millennial-scale climate variability

&lt;p&gt;A key goal of paleoclimate science is to identify the source of millennial-scale climate fluctuations. Although long-term changes in the Earth��s position relative to the Sun are the driver of climate change on timescales of �� 19 thousand years (ka), it is still incompletely understood what causes rapid sub-orbital changes in climate that were common during glacial periods. Here, we provide a continuous, precisely dated speleothem record from southeastern Alaska that spans the last 13.5 ka. Despite its location in the high latitudes of the Northern Hemisphere, this record shows an equatorial Pacific climate pattern during the end of the last deglaciation and Holocene, and is at odds with North Atlantic climate patterns, calling into question the bipolar seesaw mechanism for the Pacific realm. Because of this, we propose a new mechanism to account for sub-orbitally forced climate changes. The mechanism, termed the Walker switch, is forced by insolation and results in rapid zonal sea-surface temperature changes in the equatorial Pacific. The climatic effects of the Walker switch are propagated across the globe, including the high northern latitudes.&lt;/p&gt;

Efeito da sazonalidade sobre as respostas fisiológicas e produtivas de vacas leiteiras mestiças ao clima amazônico equatorial

Abstract The objective of this study was to evaluate the seasonal effect of months of the year upon the physiological and productive responses of crossbred dairy cows raised in an Amazonian climate. Twenty lactating cows were evaluated, fed on Brachiaria decumbens pasture, with free access to water and mineral supplementation. Data from climate variables air temperature (AT), relative humidity (RH), rainfall (RA) and temperature and humidity index (THI) were recorded dur ing the months of January to April 2019. The physiological data collected were: respiratory rate (RR, mov/min), heart rate (HR, beats/min), rectal temperature (RT, ºC), udder surface temperature (UST, ºC), body surface temperature (BST, ºC), dorsum surface temperature (DST, ºC), front surface temperature (FST, ºC) and rear shin temperature (RST). Milk production (MP) was also measured. There was a significant difference (P&lt;0.05) of RST and RR with values ranging from 34.8 to 35.5°C and 32.0 to 36.2 mov/min, respectively. There were no significant difference (P&gt;0.05) for BST, and the values for MP and THI were 3.8; 3.8; 4.6; 4.1 kg and 77.7; 79.7; 80.6; 80.1, respectively. It was concluded that there was a seasonal effect of the months of the year evaluated on the respiratory rate of animals, however, it did not change the MP and the THI. The Amazon environment is conducive to causing thermal stress in lactating cows raised on pasture, requiring the use of shading to facilitate the ability of these animals to dissipate heat.