Bean irrigate Water footprint for the middle north of the State of Mato Grosso

Abstract

The Brazilian agricultural sector is a very significant segment in terms of water resource use, especially in the state of Mato Grosso, more precisely in the Cerrado-Amazon transition region, which is home to one of the largest water security hubs in the country. Since water resources are finite and their use is intensive, quantifying water use by agriculture can contribute to the adoption of public water resource management policies. In this sense, the objective of the study was to experimentally determine the Water Footprint of irrigated winter beans for the Mid-North of the state of Mato Grosso. Using climate data obtained at the experiment site and the CROPWAT software, it was possible to calculate the evapotranspiration demand of the bean crop (Dama Carioca TAA S2) in the region and perform the supervision balance for the years 2021 to 2023. The green and blue Water Footprints were obtained using crop evapotranspiration to calculate water demand with an average of 2,381.0 m3.ha-1, while the gray Water Footprint was calculated based on the nitrogen fertilizer application rate in crops of 100 kg.ha-1, and its leaching into the soil with an average of 342.44 m3.t-1, highlighting the importance of adequate control of fertilizer application. In the study area, the Dama Carioca TAA S2 bean variety was cultivated, presenting a good average productivity of 2,921.0 kg.ha-1, exceeding regional and national averages. The average Water Footprint for the total beans was 1,157.96 m3.t-1, with 70.43% attributed to the Blue Water Footprint (815.52 m3.t-1) and 29.57% attributed to the Gray Water Footprint (342.44 m3.t-1). The absence of a Green Water Footprint (0%) reflects the practice of planting during the dry period. The results indicated that the Water Footprint was presented as an excellent indicator of water consumption for the production of beans of the Dama Carioca TAA S2 variety in the Mid-North region of Mato Grosso. These results have beneficial implications for sustainable agriculture, emphasizing the importance of conscious management of water resources to improve agricultural production, since the Water Footprint indicator contributes to the investigation of crop planting potential in certain regions.