Compound effects of drought and heat waves on fire incidence over the Amazon

Extreme drought events merely are no longer enough to provide the framework that explains exacerbated impacts of atmospheric conditions in vegetation fires. In particular, the coupled effect of Heat Waves (HW) induced by positive feedbacks between soil and atmosphere caused by drought patterns, is shown to be more likely to enhance flammability conditions. Thus, understanding the concurrence of both extreme climatic events (droughts and HWs) is crucial to quantify ecological and socioeconomic impacts of fire related to ecosystem services, human health, climate and conservation. Although these compound events are increasingly being subject of study around the globe, they are poorly explored over South America, in particular over the Amazon.Therefore, our first goal here is to analyze the simultaneous occurrence of heat waves during two major extreme droughts in Amazon rainforest, namely during the outstanding 2005 and 2010 events. Moreover, we aim to quantify the impact of these compound events on fire incidence and intensity. To accomplish these goals, we use meteorological fields from ERA-5 reanalysis, remote sensing platforms and in-situ data. HW events were assessed by analyzing the associated synoptic patterns and heat wave indexes based on temperature data from surface meteorological stations, from 1961 to 2014. The spatial and temporal patterns of fire activity were analyzed between 2003 and 2017, based on information obtained from AQUA MODIS Standard Fire products 1 km collection 6 of active fire (AF) and fire radiative power (FRP) datasets.Results show an increase of HWs during drought periods along with a rise in number of these events over the last two decades at the Amazon, presenting pikes of occurrence and extension on 2005 and 2010. We show that fire occurs more frequently during these compound events than if these events occur independently. Moreover, an enhancement in fire intensity is also verified when HWs and drought occur simultaneously

Erythrina velutina Willd. alkaloids : piecing biosynthesis together from transcriptome analysis and metabolite profiling of seeds and leaves

Introduction: Natural products of pharmaceutical interest often do not reach the drug market due to the associated low yields and difficult extraction. Knowledge of biosynthetic pathways is a key element in the development of biotechnological strategies for plant specialized metabolite production. Erythrina species are mainly used as central nervous system depressants in folk medicine and are important sources of bioactive tetracyclic benzylisoquinoline alkaloids (BIAs), which can act on several pathology-related biological targets. Objectives: In this sense, in an unprecedented approach used with a non-model Fabaceae species grown in its unique arid natural habitat, a combined transcriptome and metabolome analyses (seeds and leaves) is presented. Methods: The Next Generation Sequencing-based transcriptome (de novo RNA sequencing) was carried out in a NextSeq 500 platform. Regarding metabolite profiling, the High-resolution Liquid Chromatography was coupled to DAD and a micrOTOF-QII mass spectrometer by using electrospray ionization (ESI) and Time of Flight (TOF) analyzer. The tandem MS/MS data were processed and analyzed through Molecular Networking approach. Results: This detailed macro and micromolecular approach applied to seeds and leaves of E. velutina revealed 42 alkaloids, several of them unique. Based on the combined evidence, 24 gene candidates were put together in a putative pathway leading to the singular alkaloid diversity of this species. Conclusion: Overall, these results could contribute by indicating potential biotechnological targets formodulation of erythrina alkaloids biosynthesis as well as improve molecular databases with omic data from a non-model medicinal plant, and reveal an interesting chemical diversity of Erythrina BIA harvested in Caatinga

Erythrina velutina Willd. alkaloids: Piecing biosynthesis together from transcriptome analysis and metabolite profiling of seeds and leaves

Introduction: Natural products of pharmaceutical interest often do not reach the drug market due to the associated low yields and difficult extraction. Knowledge of biosynthetic pathways is a key element in the development of biotechnological strategies for plant specialized metabolite production. The scarce studies regarding non-model plants impair advances in this field. Erythrina spp. are mainly used as central nervous system depressants in folk medicine and are important sources of bioactive tetracyclic benzylisoquinoline alkaloids, which can act on several pathology-related biological targets. Objective: Herein the purpose is to employ combined transcriptome and metabolome analyses (seeds and leaves) of a non-model medicinal Fabaceae species grown in its unique arid natural habitat. The study tries to propose a putative biosynthetic pathway for the bioactive alkaloids by using an omic integrated approach. Methods: The Next Generation Sequencing-based transcriptome (de novo RNA sequencing) was carried out in a Illumina NextSeq 500 platform. Regarding the targeted metabolite profiling, Nuclear Magnetic Resonance and the High-Performance Liquid Chromatography coupled to a micrOTOF-QII, High Resolution Mass Spectrometer, were used. Results: This detailed macro and micromolecular approach applied to seeds and leaves of E. velutina revealed 42 alkaloids by metabolome tools. Based on the combined evidence, 24 gene candidates were put together in a putative pathway leading to the singular alkaloid diversity of this species. Conclusion: These results contribute by indicating potential biotechnological targets Erythrina alkaloids biosynthesis as well as to improve molecular databases with omic data from a non-model medicinal plant. Furthermore, they reveal an interesting chemical diversity in Erythrina velutina harvested in Caatinga. Last, but not least, this data may also contribute to tap Brazilian biodiversity in a rational and sustainable fashion, promoting adequate public policies for preservation and protection of sensitive areas within the Caatinga

Compound effects of drought and heat waves on fire incidence over the Amazon

Extreme drought events merely are no longer enough to provide the framework that explains exacerbated impacts of atmospheric conditions in vegetation fires. In particular, the coupled effect of Heat Waves (HW) induced by positive feedbacks between soil and atmosphere caused by drought patterns, is shown to be more likely to enhance flammability conditions. Thus, understanding the concurrence of both extreme climatic events (droughts and HWs) is crucial to quantify ecological and socioeconomic impacts of fire related to ecosystem services, human health, climate and conservation. Although these compound events are increasingly being subject of study around the globe, they are poorly explored over South America, in particular over the Amazon.Therefore, our first goal here is to analyze the simultaneous occurrence of heat waves during two major extreme droughts in Amazon rainforest, namely during the outstanding 2005 and 2010 events. Moreover, we aim to quantify the impact of these compound events on fire incidence and intensity. To accomplish these goals, we use meteorological fields from ERA-5 reanalysis, remote sensing platforms and in-situ data. HW events were assessed by analyzing the associated synoptic patterns and heat wave indexes based on temperature data from surface meteorological stations, from 1961 to 2014. The spatial and temporal patterns of fire activity were analyzed between 2003 and 2017, based on information obtained from AQUA MODIS Standard Fire products 1 km collection 6 of active fire (AF) and fire radiative power (FRP) datasets.Results show an increase of HWs during drought periods along with a rise in number of these events over the last two decades at the Amazon, presenting pikes of occurrence and extension on 2005 and 2010. We show that fire occurs more frequently during these compound events than if these events occur independently. Moreover, an enhancement in fire intensity is also verified when HWs and drought occur simultaneously