Atmospheric moisture contribution to the growing season in the Amazon arc of deforestation

Bibliographic Data

ID15547395
AuthorsJohn C O’Connor (0000-0003-1431-0651, Utrecht University, corresponding author), Maria J Santos (0000-0002-6558-7477, University of Zurich), Stefan C Dekker (0000-0001-7764-2464, Utrecht University), Karin T Rebel (0000-0002-1722-3935, Utrecht University), Obbe A Tuinenburg (0000-0001-6895-0094, Utrecht University)
Year2021
Volume16
Issue8
Pages084026-084026
Publication date2021-07-09
Open AccessYes
TypeARTICLE
VenueEnvironmental Research Letters (JOURNAL)
Journal identifiersISSN: 1748-9326 • E-ISSN: 1748-9326
PublisherIOP Publishing (PUBLISHER • GB)
DOI10.1088/1748-9326/ac12f0
OpenAlexW3182492887
LanguageEN
Citations received2
References cited50

The Amazon moisture recycling system has been widely examined because it is fundamental to maintain some of the global climate processes, however, we have yet to know to what extent the agricultural growing season is dependent on the evapotranspiration contribution from the Amazon forest. Here we use a moisture tracking model to calculate the forest’s contribution to downwind precipitation. Specifically, we calculate the influence of moisture recycling on the seasonality of precipitation in the arc of deforestation with respect to the agricultural growing season. We calculated the wet season start, end and length using three scenarios (a) total precipitation with existing vegetation cover; (b) where we replace forest’s contribution to precipitation by replacing it with the equivalent from short vegetation; (c) where the forest’s contribution to precipitation is completely removed. We found that forest moisture recycling contributes up to 40% of monthly precipitation in the arc of deforestation. However, there is a strong spatial gradient in the forest’s contribution to precipitation, which decreases from west to east. This gradient also coincides with suitability for double-cropping agriculture. Our scenarios excluding precipitation originating from forest indicated that forest is a key contributing factor in determining the wet season start. We found that even when the precipitation originating from forest was replaced by short vegetation there was a significant delay in the wet season start in our study regions. Interestingly the wet season end was more resilient to changes in precipitation source. However it is clear that moisture recycling plays a key role in determining the wet season end as when forest’s contribution to precipitation was entirely removed the wet season end arrived significantly earlier. These differences in wet season length were not detectable in the eastern states of Tocantins and Maranhão, as much less of the precipitation in these states originates from the forest. Our findings demonstrate the importance of forest in supporting double-cropping agriculture in the arc of deforestation. As agricultural intensification by double-cropping increases land-use efficiency, it may also reduce the demand for further deforestation. Therefore it is important to identify how the current forest extent provides this important ecosystem service

Amazon rainforest · Atmospheric sciences · Climatology · Deforestation (computer science · Dry season · Evapotranspiration · Geography · Growing season · Meteorology · Moisture · Precipitation · Vegetation (pathology · Water content · Wet season · Conservation, Biodiversity, and Resource Management · Environmental Science · Land Use and Ecosystem Services · Plant Water Relations and Carbon Dynamics · Ecology · Geology

Tools

Open DOIOpen Access