RESUMO Compreender o desenvolvimento do coqueiro-anão-verde é essencial para melhorar seu manejo. Objetivou-se caracterizar e entender a sazonalidade do desenvolvimento e a produção de frutos do coqueiro-anão-verde sob condições de sequeiro e irrigação na região nordeste do Pará, Brasil. Foram monitorados os diâmetros longitudinal e transversal, massa e produtividade dos frutos, além do número de folhas vivas, cachos vivos, frutos dos cachos nº 11 e 14 e fores femininas. Os cocos entre os cachos nº 20 e 22 apresentam maiores dimensões e biomassa (fresca e seca). A repartição dos componentes da produção varia conforme a época do ano, sendo a massa de albúmen líquido, componente de maior enfoque comercial, maior no período chuvoso, com menores perdas percentuais no cultivo irrigado. A sazonalidade meteorológica desempenha papel fundamental na queda das fores e no aborto dos frutos, contribuindo diretamente para a quantidade de frutos produzidos. coqueiroanãoverde coqueiro anão verde manejo Objetivouse Objetivou se Pará Brasil transversal vivas vivos 1 femininas 2 fresca seca. seca . seca) ano líquido comercial chuvoso irrigado produzidos

ABSTRACT Understanding the green dwarf coconut palm development is essential to improve its management. This study aimed to characterize and understand the seasonality of the green dwarf coconut palm development and yield under rainfed and irrigated conditions in the northeastern region of the Pará state, Brazil. The longitudinal and transverse diameters, fruit mass and yield, in addition to the number of live leaves, live bunches, fruits of the bunches nº 11 and 14 and female fowers were monitored. The coconuts between the bunches nº 20 and 22 showed larger dimensions and biomass (fresh and dry). The partition of the production components varies according to the time of the year, with the liquid albumen mass, which is a component of greater commercial focus, being higher in the rainy season, with lower percentage losses in the irrigated cultivation. The meteorological seasonality plays a key role in fower dropping and fruit abortion, directly contributing to the amount of produced fruits. management state Brazil diameters leaves 1 monitored 2 fresh dry. dry . dry) year focus season cultivation abortion

ABSTRACT Inadequate management of the irrigation system has compromised yield and favoured the degradation and waste of water resources. To ensure efficient irrigation management, providing yield increases, sustainability in the use of water resources and reduction of production costs, studies about the water demand of coconut palms are needed. The objective of this study was to determine the energy partition, crop evapotranspiration (ETc), and the simple crop coefficients (Kc) of the green dwarf coconut palms in Santa Izabel do Pará, Pará, Brazil. The experiment was carried out in a coconut plantation at Reunidas Sococo Farm, with an area of approximately 7 ha in a triangular spacing of 7.5 × 7.5 m, during 2020 and 2021. The ETc was determined by the Bowen ratio method, with measurements of temperature and relative humidity at two levels above the crop canopy and reference evapotranspiration (ETo) by the FAO Penman-Monteith method, using data from the National Institute of Meteorology. The Kc was determined by the ratio between ETc and ETo. The total water demand of the coconut palm was 489 (2020) and 480 mm (2021), with a daily average of 4.21 (2020) and 4.14 mm (2021) for the dry season. The mean value of Kc was 1.06 (± 0.12). Evapotranspiration was driven mainly by energy availability, associated with a control of atmospheric demand on Kc values, suggesting a possible influence of coconut trees on Kc values even under good water availability and small variability in vegetation cover. increases costs needed partition ETc, , (ETc) (Kc Pará Brazil Farm 75 5 7. m 202 2021 method ETo (ETo PenmanMonteith Penman Monteith Meteorology 48 (2020 2021, 421 4 21 4.2 414 14 4.1 (2021 season 106 1 06 1.0 ± ( 0.12. 012 0.12 . 0 12 0.12) cover (ETc 20 (202 42 2 4. 41 10 1. 01 0.1 (20 0. (2

Abstract We investigate the balance of radiation and energy over a lime orchard in Eastern Amazon and how it relates to environmental conditions. We found that lime trees aged between 6 and 7 years old reflect 11.0% to 14.5% of incoming shortwave radiation, and the latent heat flux corresponds to 57.6% and 66.6% of the daily net radiation in the dry season (August - November) of 2020, and 2021, respectively. The soil heat flux represents 1% to 2% of the daily net radiation. Evapotranspiration was much lower than the reference evapotranspiration from August to November in 2019 and 2020. Evapotranspiration increased proportionally to the reference evapotranspiration from August to November 2021. This increase may be explained by weather conditions, such as the frequent rainfall during the dry season of 2021, in the same period when the energy for evapotranspiration is higher. Also, the high relative humidity between August and November 2021 may have favored the opening of stomata, increasing the orchard's evapotranspiration. The crop coefficient ranges between 0.74 and 0.84. conditions 110 11 0 11.0 145 14 5 14.5 576 57 57.6 666 66 66.6 2020 respectively 1 2 201 higher Also 202 stomata orchards s 074 74 0.7 084 84 0.84 11. 14. 57. 66. 20 07 0. 08 8 0.8

Resumo Investiga-se o balanço de radiação e energia sobre um pomar de limão na Amazônia Oriental e como ele se relaciona com as condições ambientais. Foi descoberto que a lima ácida Tahiti com idades entre 6 e 7 anos refletem de 11,0% a 14,5% da radiação de ondas curtas recebidas, e o fluxo de calor latente corresponde a 57,6% e 66,6% do saldo de radiação diária nos períodos secos (agosto a novembro) de 2020 e 2021, respectivamente. O fluxo de calor do solo representa de 1% a 2% do saldo de radiação diário. A evapotranspiração foi muito menor que a evapotranspiração de referência de agosto a novembro em 2019 e 2020. A evapotranspiração aumentou proporcionalmente à evapotranspiração de referência de agosto a novembro de 2021. Esse aumento pode ser explicado pelas condições climáticas, como as chuvas frequentes durante o período seco de 2021, no mesmo período em que a energia para evapotranspiração é maior. Além disso, a alta umidade relativa entre agosto e novembro de 2021 pode ter favorecido a abertura dos estômatos, aumentando a evapotranspiração do pomar. O coeficiente de cultura variou entre 0,74 e 0,84. Investigase Investiga ambientais 110 11 0 11,0 145 14 5 14,5 recebidas 576 57 57,6 666 66 66,6 202 respectivamente 1 2 diário 201 climáticas maior disso estômatos 074 74 0,7 084 84 0,84 11, 14, 57, 66, 20 07 0, 08 8 0,8

ABSTRACT The climate risk zoning was carried out for cowpea cultivated in northeastern Amazonia, Pará state, Brazil. Système d’Analyse Régionale des Risques Agroclimatologiques (SARRA) crop model was used and calibrated from data obtained in field experiments conducted between 2013 and 2016 in Castanhal, state of Pará. Low climate risk areas were defined as those with water requirement satisfaction index (WRSI) greater than or equal to 0.5 during flowering and early grain development and less than 20 mm of total rainfall during grain maturation and harvest for at least 80% of the simulated sowings of the crop. Simulations of the current and future climate conditions were carried out with the regional climate modelling system version 4 (RegCM4) nested with the HadGEM2 global circulation model with RCP 4.5 IPCC-AR4 scenario. The results show that climate changes are likely to reduce the duration of the optimal period for sowing cowpea in the mentioned region.

Resumo Dois modelos destinados a estimar a radiação solar incidente na superfície terrestre foram calibrados em seis localidades no nordeste do Pará (Belém, Cametá, Conceição do Araguaia, Marabá, Soure e Tucuruí). O primeiro é a equação de Angröm-Prescott (AP), que requer observações do número de horas de brilho solar. O segundo modelo é uma versão modificada da fórmula de radiação de Hargreaves (MH), que requer observações da temperatura máxima e mínima diárias. Ambos os modelos foram calibrados para estimar a radiação solar diária e mensal. A calibração de ambas as equações para cada estação (i.e., estação menos chuvosa e estação chuvosa) em cada localidade foi também realizada. AP tem desempenho cerca de 74% maior que MH para estimativas diárias (excluindo Soure) e 83% para estimativas mensais (excluindo Soure e Tucuruí). O uso de equações calibradas para cada estação aumenta em 0,68% o desempenho de AP e também aumenta o desempenho de MH, medido pelo índice de desempenho, na maior parte das localidades, nas estimativas de radiação solar diária. O desempenho de ambos os modelos é muito maior quando estimando a radiação solar mensal em relação a radiação solar diária, com aumento do índice de desempenho de, em média, 10,95% para AP.

Abstract Two models aimed to estimate solar irradiance were calibrated in six locations in Northeastern Pará (Belém, Cametá, Conceição do Araguaia, Marabá, Soure, and Tucuruí). The first one is the equation of Angström-Prescott (AP), which requires observations of sunshine duration hours. The second model is a modified version of Hargreaves' radiation formula (MH), which requires observations of daily maximum and daily minimum air temperatures. Both models were calibrated to estimate daily and monthly solar radiation. The calibration of both equations for each season (i.e., dry season and wet season) in each location was also tested. AP has an average performance about 74% higher than MH for daily estimates (excluding Soure) and 83% higher than MH for monthly estimates (excluding Soure and Tucuruí). The use of seasonally calibrated equations slightly improves the performance of AP, measured by the performance index, by 0.68% and improves the performance of MH in most locations, when estimating daily solar radiation. The performance of both models is much higher when estimating monthly solar radiation than daily solar radiation, with an increase of the performance index of 10.95% for AP.