Because of a lack of direct measurements, the presence and persistence of glyphosate and its main metabolite aminomethylphosphonic acid (AMPA) in agricultural soils of Brazil remains unknown. This paper aims at reporting glyphosate and AMPA contents in Brazilian field crop soils at the country scale from southern states to eastern Amazon. Brazilian field crop farmers are among the highest users of glyphosate-based herbicides (GBH) in the world. Soybean and corn field crop soils from 17 sites were collected at two depths (i.e. 0-20 cm and 20-40 cm) in 2016 and 2018. The study area encompasses three regions of Brazil: southern Brazil, central-west Brazil and eastern Amazon, all having in common intensive, conventional, large-scale grain farming. ßGlyphosate and AMPA contents were measured using a GC-ECD following soil extraction. Both chemicals were ubiquitously detected in soils cultivated under various agricultural practices ranging from ploughing to no-till ones. Average measured glyphosate and AMPA contents were 0.08 ± 0.09 µg/g and 0.17 ± 0.16 µg/g respectively with maximum values of 0.57 µg/g and 0.98 µg/g. Glyphosate plus AMPA contents in the top 40 cm of soils presented cumulated amounts exceeding the annual glyphosate inputs via GBH. This is interpreted as a multiannual persistence of these chemicals in Brazilian agricultural soils. Downward migration of glyphosate and AMPA is also suspected with regard to the vertical distribution of these chemicals along with deeper soil horizons. This study highlights the backlash of conservation agriculture as far as glyphosate and AMPA presence in agricultural soils are concerned. These compounds persistence in Brazilian soils appear to be longer than what is usually reported in the literature, especially so for tropical environments. The worldwide concern about the ubiquitous presence of glyphosate and AMPA in the environment needs a broader screening in Brazilian field crop soils since the majority of the available data comes from Argentina, Europe and to a lesser extent North America.

This work compares methods of climate measurements, such as those used to measure evapotranspiration, precipitation, net radiation, and temperature. The satellite products used were compared and evaluated against flux tower data. Evapotranspiration was validated against the SSEBop monthly and GLEAM daily and monthly products, respectively, and the results were RMSE = 24.144 mm/month, NRMSE = 0.223, r2 = 0.163, slope = 0.411; RMSE = 1.781 mm/day, NRMSE = 0.599, r2 = 0.000, slope = 0.006; RMSE = 36.17 mm/month, NRMSE = 0.401, r2 = 0.002, and slope = 0.026. Precipitation was compared with the CHIRPS data, K67 was not part of the CHIRPS station correction. The results for both the daily and monthly comparisons were RMSE = 18.777 mm/day, NRMSE = 1.027, r2 = 0.086, slope = 0.238 and RMSE = 130.713 mm/month, NRMSE = 0.706, r2 = 0.402, and slope = 0.818. The net radiation validated monthly with CERES was RMSE = 75.357 W/m2, NRMSE = 0.383, r2 = 0.422, and slope = 0.867. The temperature results, as compared to MOD11C3, were RMSE = 2.829 °C, NRMSE = 0.116, r2 = 0.153, and slope = 0.580. Comparisons between the remote sensing products and validation against the ground data were performed on a monthly basis. GLEAM and CHIRPS daily were the data sets with considerable discrepancy.

The objective of this study is to demonstrate the use of infrared thermography in a geoscience context to diagnose thermal and hydrological patterns in soils with crops irrigated using clay pots in western Pará, Amazonia. The thermographic images were obtained in a technological reference unit (URT) installed as part of the IrrigaPote project in the community of Lavras, western Pará. Images were taken in the field and thermal patterns were analyzed for the following targets: T1: Acerola (Malpighia emarginata) trees with leaf litter covering the soil; T2: Acerola trees with no leaf litter covering the soil; T3: Soil with litter cover; T4: Soil with no litter cover, and T5: a backyard agroforest with a large tree over 100 years old with litter covering the soil. The data were stratified into extreme and average values and thermal amplitude, and soil humidity was measured. The near infrared thermography diagnosis and the thermograms were analyzed using the program Flir Tools (6.3v). The thermal targets were randomly selected, with 10 targets for each of the five (05) treatments, for a total of 50 samples. Descriptive statistics were done using a 5% significance level. There were significant differences between exposed soil (T4=61.0°C) and soil covered by litter (T3=43.8°C). The soil shaded by acerola had an average temperature of (T1=33.6°C) and that of the soil shaded but with litter and outside the URT was higher (T2=32.7°C), demonstrating the effects of soil moisture due to irrigation with the clay pots. The lowest temperatures (T5=30.3°C) were found for the large, old tree with the soil covered by litter on the property of the rural producer. The thermal regulation provided by the irrigation using clay pots is in agreement with the Sustainable Development Objectives (SDO), principally SDO 2 with respect to provision of food production during the entire year, and SDO 6, 9 and 12 due to the reuse of rainfall in an agricultural setting, which promotes responsible production, and finally with SDO 13 as a strategy for thermal regulation to mitigate the effects of climate change. Infrared thermography has great potential to be applied to different areas of geoscience.

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A dinâmica dos nutrientes no solo é resultado da interação de vários fatores, e, no SPD, os mecanismos que governam são modificados em velocidade e/ou intensidade pela redução do revolvimento do solo e manutenção dos resíduos culturais na superfície do solo. Anomalias em plantas relacionadas a solo são diretamente ligadas aos níveis críticos e tóxicos dos atributos físico, químico ou biológicos de solo, logo, a fertilidade do solo é um dos fatores de predisposição das plantas aos patógenos. A soja louca-II é uma anomalia que causa cerda 40% perdas em lavouras e sem causa definida. Objetivo do foi avaliar os teores e variância dos atributos químicos de solos em áreas de com ocorrência da Soja Louca II. Realizaram-se 180 amostras em 20 cm, 40cm e 60cm de profundidas em áreas com e sem a ocorrência da anomalia em propriedades nos municípios de Santarém, Belterra e Mojui dos Campos na região oeste do Pará Os Atributos químicos Ph, P, K, Na, Ca, Mg, Al, Fe, Cu, Zn, Mn e CTC  e Teor de Argila natural foram submetidos a análise descritiva e análise de variâncias no programa Biostat versão 5.3. Não foram encontras diferenças significativas entre os atributos nos tratamentos, sendo consideradas estatisticamente semelhantes as áreas com  e sem ocorrência da Soja Louca II, porem com terrores de micronutriente em níveis tóxicos na maior parte das amostras em ambos os tratamentos em todas as profundidades coletadas. Os atributos que apresentaram maior e menor Coeficiente de Variação foram pH ( 7.45%)  e  Zn (198.17% )  a 20cm, pH (6,66%) e Cu (250,70%) a 40cm e pH (5,84%) e Cu (238,74%) a 60m de profundidade. A análise de variância dos atributos químicos não apresentou diferenças significativa entre as profundidades.