Composição da matéria orgânica em solos de seis zonas pedoclimáticas de Magdalena (Colômbia)

[ES] Los suelos al noreste del departamento del Magdalena (Colombia) afrontan una creciente degradación, principalmente por las bajas tasas de acumulación de materia orgánica del suelo (MOS) y su reducido período de transformación. Tradicionalmente se han realizado estudios tendentes a mitigar esta situación, pero todos se han centrado en aspectos cuantitativos analizando los contenidos totales de MOS. Por tanto, en el presente estudio se propuso determinar la composición molecular de la MOS en suelos de seis zonas con diferentes características edafoclimáticas en zonas de bosques húmedos y secos tropicales, con una altitud entre 5-956 msnm, temperatura media entre 24-30 °C, precipitación media entre 663-2000 mm y diferentes usos actuales (bosques y cultivos varios). Para ello se caracterizó por pirólisis (acoplada a cromatografía de gases y espectroscopía de masas) la MOS extraída con NaOH 0.1M de muestras superficiales en suelos cultivados y de bosques. Fueron cuantificados 110 productos de pirólisis en la siguiente proporción: compuestos con N (34,1% ± 5,1%), polisacáridos (21,1% ± 7.1%), aromáticos (20,0% ± 4.5%), alifáticos (7,7%± 1,4%), fenoles (7,0% ± 5,0%), poliaromáticos (3,6% ± 0,9%), ligninas (0,3% ± 0,3%) y otros compuestos (0,2% ± 0,1%). A través del análisis de varianza no se encontraron diferencias estadísticas entre los productos de pirólisis para usos del suelo (bosque y cultivados), pero sí para las zonas muestreadas. Por otro lado el análisis factorial por componentes principales permitió reducir el conjunto de compuestos productos de pirólisis en dos variables sintéticas que explicaron el 51% de la variabilidad total. Aunque en todas las zonas se evidenció una MOS con un grado importante de descomposición, el factor 1 permitió separar entre MOS de origen microbiano relativamente descompuesta y MOS fresca o de descomposición lenta y de origen vegetal. En términos generales, las zonas con mayor pluviosidad y menores promedios de temperatura mostraron una contribución relativamente alta de MOS microbiana y, en menor proporción, de MOS de origen vegetal tanto para suelos de bosques como para suelos de cultivo, en contraste con las zonas más secas que presentaron mayor proporción de MOS de origen vegetal.[EN] The soils in the NE of the Magdalena province (Colombia) are subject to intense degradation primarily because of the low accumulation rate of soil organic matter (SOM) and its fast turnover. Numerous traditional studies have aimed to mitigate this situation, focusing on the analysis of total SOM contents. The present study aimed to determine SOM quality from six areas under humid and dry tropical forest with different pedoclimatic conditions, using molecular characterization. For each area, sites with different current land use were studied, including forest and cultivated sites. We applied analytical pyrolysis (pyrolysis-GC/MS) to aqueous NaOH-extractable SOM from surface soil samples. One-hundred and ten pyrolysis products were identified and quantified, from the following chemical groups: N-containing compounds (34.1 ± 5.1%), carbohydrate markers (21.1% ± 7.1%), monocyclic aromatic compounds (20.0% ± 4.5%), aliphatic compounds (7.7% ± 1.4%), phenols (7.0% ± 5.0%), polycyclicaromatic compounds (3.6% ± 0.9 %), lignin products (0.3% ± 0.3%) and other compounds (0.2% ± 0.1%). SOM ofall studied areas showed a large proportion of N-containing products, indicating a high contribution from microbial material to the SOM. Multivariate statistics allowed for the differentiation between microbial-derived and plantderived SOM (Factor 1) and the relative proportion of burning residues (Factor 2), and indicated that pedoclimatic conditions exert more influence on SOM composition (cool and humid zones were enriched in microbial SOM while dry zones contained more plant-derived SOM) than land use for the studied soils.[PT] Os solos a nordeste da provincía de Magdalena (Colombia) estão submetidos a uma crescente degradação, devido principalmente às baixas taxas de acumulação de materia orgânica do solo (MOS) e ao seu reduzido período de transformação. Tradicionalmente têm sido realizados estudos tendentes a mitigar esta situação,mas todos eles focados em aspetos quantitativos analisando os teores totais de MOS. Por este motivo, no presente estudo propõe-se determinar a composição molecular da MOS em solos de seis zonas com diferentes características pedoclimáticas em áreas de floresta húmida e seca tropical, con uma altitude entre 5-956 msnm, temperatura media entre 24- 30 °C, precipitação media entre 663-2000 mm e diferentes usos atuais (floresta e zonas cultivadas). Para esse efeito, caraterizou-se por pirólise (associada a cromatografía gasosa e espetroscopía de massa) a MOS extraída con NaOH 0.1 M de amostras superficiais em solos cultivados e de floresta. Quantificaram-se 110 produtos de pirólise na seguinte proporção: compostos com N (34,1% ± 5,1%), polissacáridos (21,1% ± 7,1%), aromáticos (20,0% ± 4,5%), alifáticos (7,7% ± 1,4%), fenóis (7,0% ± 5,0%), poliaromáticos (3,6% ± 0,9%), lenhina (0,3% ± 0,3%) e outros compostos (0,2% ± 0,1%). Através de análise de variância não se encontraram diferenças estatísticas entre os produtos de pirólise para diferentes usos do solo (floresta e cultivados), mas sim para as zonas amostradas. Por outro lado a análise factorial por componentes principais permitiu reduzir o conjunto de compostos produto da pirólise em duas variáveis sintéticas que permitiram explicar 51% da variabilidade total. Ainda que em todas as zonas se tenha evidenciado uma MOS com um importante grau de descomposição, o factor 1 permitiu separar entre MOS de origem microbiana relativamente decomposta e MOS fresca ou de descomposição lenta e de origem vegetal. Em termos gerais, as zonas con maior pluviosidade e menores temperaturas médias apresentaram uma composição relativamente alta de MOS microbiana e, em menor proporção, de MOS de origem vegetal tanto para solos de floresta como para solos cultivados, contrastando com as zonas mais secas que apresentaram maior proporção de MOS de origem vegetal.Peer Reviewe

Study protocol of a randomized controlled trial comparing Mindfulness-Based Stress Reduction with treatment as usual in reducing psychological distress in patients with lung cancer and their partners: the MILON study

BACKGROUND: Lung cancer is the leading cause of cancer death worldwide and characterized by a poor prognosis. It has a major impact on the psychological wellbeing of patients and their partners. Recently, it has been shown that Mindfulness-Based Stress Reduction (MBSR) is effective in reducing anxiety and depressive symptoms in cancer patients. The generalization of these results is limited since most participants were female patients with breast cancer. Moreover, only one study examined the effectiveness of MBSR in partners of cancer patients. Therefore, in the present trial we study the effectiveness of MBSR versus treatment as usual (TAU) in patients with lung cancer and their partners. METHODS/DESIGN: A parallel group, randomized controlled trial is conducted to compare MBSR with TAU. Lung cancer patients who have received or are still under treatment, and their partners are recruited. Assessments will take place at baseline, post intervention and at three-month follow-up. The primary outcome is psychological distress (i.e. anxiety and depressive symptoms). Secondary outcomes are quality of life (only for patients), caregiver appraisal (only for partners), relationship quality and spirituality. In addition, cost-effectiveness ratio (only in patients) and several process variables are assessed. DISCUSSION: This trial will provide information about the clinical and cost-effectiveness of MBSR compared to TAU in patients with lung cancer and their partners. TRIAL REGISTRATION: ClinicalTrials.gov NCT01494883

Cohort profile of PLUTO: a perioperative biobank focusing on prediction and early diagnosis of postoperative complications

PURPOSE: Although elective surgery is generally safe, some procedures remain associated with an increased risk of complications. Improved preoperative risk stratification and earlier recognition of these complications may ameliorate postoperative recovery and improve long-term outcomes. The perioperative longitudinal study of complications and long-term outcomes (PLUTO) cohort aims to establish a comprehensive biorepository that will facilitate research in this field. In this profile paper, we will discuss its design rationale and opportunities for future studies. PARTICIPANTS: Patients undergoing elective intermediate to high-risk non-cardiac surgery are eligible for enrolment. For the first seven postoperative days, participants are subjected to daily bedside visits by dedicated observers, who adjudicate clinical events and perform non-invasive physiological measurements (including handheld spirometry and single-channel electroencephalography). Blood samples and microbiome specimens are collected at preselected time points. Primary study outcomes are the postoperative occurrence of nosocomial infections, major adverse cardiac events, pulmonary complications, acute kidney injury and delirium/acute encephalopathy. Secondary outcomes include mortality and quality of life, as well as the long-term occurrence of psychopathology, cognitive dysfunction and chronic pain. FINDINGS TO DATE: Enrolment of the first participant occurred early 2020. During the inception phase of the project (first 2 years), 431 patients were eligible of whom 297 patients consented to participate (69%). Observed event rate was 42% overall, with the most frequent complication being infection. FUTURE PLANS: The main purpose of the PLUTO biorepository is to provide a framework for research in the field of perioperative medicine and anaesthesiology, by storing high-quality clinical data and biomaterials for future studies. In addition, PLUTO aims to establish a logistical platform for conducting embedded clinical trials. TRIAL REGISTRATION NUMBER: NCT05331118

Composición de la materia orgánica en los suelos de seis zonas edafoclimáticas del Magdalena (Colombia)

The soils in the NE of the Magdalena province (Colombia) are subject to intense degradation primarily because of the low accumulation rate of soil organic matter (SOM) and its fast turnover. Numerous traditional studies have aimed to mitigate this situation, focusing on the analysis of total SOM contents. The present study aimed to determine SOM quality from six areas under humid and dry tropical forest with different pedoclimatic conditions, using molecular characterization. For each area, sites with different current land use were studied, including forest and cultivated sites. We applied analytical pyrolysis (pyrolysis-GC/MS) to aqueous NaOH-extractable SOM from surface soil samples. One-hundred and ten pyrolysis products were identified and quantified, from the following chemical groups: N-containing compounds (34.1 ± 5.1%), carbohydrate markers (21.1% ± 7.1%), monocyclic aromatic compounds (20.0% ± 4.5%), aliphatic compounds (7.7% ± 1.4%), phenols (7.0% ± 5.0%), polycyclic aromatic compounds (3.6% ± 0.9 %), lignin products (0.3% ± 0.3%) and other compounds (0.2% ± 0.1%). SOM of all studied areas showed a large proportion of N-containing products, indicating a high contribution from microbial material to the SOM. Multivariate statistics allowed for the differentiation between microbial-derived and plant-derived SOM (Factor 1) and the relative proportion of burning residues (Factor 2), and indicated that pedoclimatic conditions exert more influence on SOM composition (cool and humid zones were enriched in microbial SOM while dry zones contained more plant-derived SOM) than land use for the studied soils.Los suelos al noreste del departamento del Magdalena (Colombia) afrontan una creciente degradación, principalmente por las bajas tasas de acumulación de materia orgánica del suelo (MOS) y su reducido período de transformación. Tradicionalmente se han realizado estudios tendentes a mitigar esta situación, pero todos se han centrado en aspectos cuantitativos analizando los contenidos totales de MOS. Por tanto, en el presente estudio se propuso determinar la composición molecular de la MOS en suelos de seis zonas con diferentes características edafoclimáticas en zonas de bosques húmedos y secos tropicales, con una altitud entre 5-956 msnm, temperatura media entre 24-30 °C, precipitación media entre 663-2000 mm y diferentes usos actuales (bosques y cultivos varios). Para ello se caracterizó por pirólisis (acoplada a cromatografía de gases y espectroscopía de masas) la MOS extraída con NaOH 0.1M de muestras superficiales en suelos cultivados y de bosques. Fueron cuantificados 110 productos de pirólisis en la siguiente proporción: compuestos con N (34,1% ± 5,1%), polisacáridos (21,1% ± 7.1%), aromáticos (20,0% ± 4.5%), alifáticos (7,7%± 1,4%), fenoles (7,0% ± 5,0%), poliaromáticos (3,6% ± 0,9%), ligninas (0,3% ± 0,3%) y otros compuestos (0,2% ± 0,1%). A través del análisis de varianza no se encontraron diferencias estadísticas entre los productos de pirólisis para usos del suelo (bosque y cultivados), pero sí para las zonas muestreadas. Por otro lado el análisis factorial por componentes principales permitió reducir el conjunto de compuestos productos de pirólisis en dos variables sintéticas que explicaron el 51% de la variabilidad total. Aunque en todas las zonas se evidenció una MOS con un grado importante de descomposición, el factor 1 permitió separar entre MOS de origen microbiano relativamente descompuesta y MOS fresca o de descomposición lenta y de origen vegetal. En términos generales, las zonas con mayor pluviosidad y menores promedios de temperatura mostraron una contribución relativamente alta de MOS microbiana y, en menor proporción, de MOS de origen vegetal tanto para suelos de bosques como para suelos de cultivo, en contraste con las zonas más secas que presentaron mayor proporción de MOS de origen vegetal.Os solos a nordeste da provincía de Magdalena (Colombia) estão submetidos a uma crescente degradação, devido principalmente às baixas taxas de acumulação de materia orgânica do solo (MOS) e ao  seu reduzido período de transformação. Tradicionalmente têm sido realizados estudos tendentes a mitigar esta situação,mas todos eles focados em aspetos quantitativos analisando os teores totais de MOS. Por este motivo, no presente estudo propõe-se determinar a composição molecular da MOS em solos de seis zonas com diferentes características pedoclimáticas em áreas de floresta húmida e seca tropical, con uma altitude entre 5-956 msnm, temperatura media entre 24-30 °C, precipitação media entre 663-2000 mm e diferentes usos atuais (floresta e zonas cultivadas). Para esse efeito, caraterizou-se por pirólise (associada a cromatografía gasosa e espetroscopía de massa) a MOS extraída con NaOH 0.1 M de amostras superficiais em solos cultivados e de floresta. Quantificaram-se 110 produtos de pirólise na seguinte proporção: compostos com N (34,1% ± 5,1%), polissacáridos (21,1% ± 7,1%), aromáticos (20,0% ± 4,5%), alifáticos (7,7% ± 1,4%), fenóis (7,0% ± 5,0%), poliaromáticos (3,6% ± 0,9%), lenhina (0,3% ± 0,3%) e outros compostos (0,2% ± 0,1%). Através de análise de variância não se encontraram diferenças estatísticas entre os produtos de pirólise para diferentes usos do solo (floresta e cultivados), mas sim para as zonas amostradas. Por outro lado a análise factorial por componentes principais permitiu reduzir o conjunto de compostos produto da pirólise em duas variáveis sintéticas que permitiram explicar 51% da variabilidade total. Ainda que em todas as zonas se tenha  evidenciado uma MOS com um importante grau de descomposição, o factor 1 permitiu separar entre MOS de origem microbiana relativamente decomposta e MOS fresca ou de descomposição lenta e de origem vegetal. Em termos gerais, as zonas con maior pluviosidade e menores temperaturas médias apresentaram uma composição relativamente alta de MOS microbiana e, em menor proporção, de MOS de origem vegetal tanto para solos de floresta como para solos cultivados, contrastando com as zonas mais secas que apresentaram maior proporção de MOS de origem vegetal

Fossil redox-conditions influence organic matter composition in loess paleosols

The soil memory recorded in paleosols of loess-paleosol sequences is an important contributor to our understanding of past climatic conditions. Molecular proxies based on the organic matter preserved in paleosols form an essential part of this record, but the long-term preservation of SOM is poorly understood, especially for sediment traps and slope profiles. This paper addresses the composition of organic material from the Early Weichselian A-horizons of the Rocourt paleosol, a major paleostratigraphic marker for the Eemian and Early Weichselian in Western Europe. NaOH-extractable organic matter from an exceptionally thick Rocourt profile in the Kesselt Quarry (Belgian Loess Belt) was analyzed by pyrolysis-Gas Chromatography/Mass Spectrometry (pyrolysis-GC/MS) and the results evaluated against paleopedological data. The molecular composition of the organic matter at Kesselt was compared with reference samples from two nearby quarries (including the type locality at Veldwezelt-Hezerwater), and to a sample from the contemporary Nussloch sequence in Germany. The SOM composition found at the four sites indicated a large content of microbial matter and was dominated by carbohydrates and N compounds, many of which were not reported before from SOM pyrolysates. Differences in the molecular composition between samples, both within profiles and between sites, coincided with differences in landscape position (slope-shoulder-plateau) and fossil redox conditions (surface gleys). Samples form drier and more upland situations contained more burnt material, while samples from slope profiles and surface gleys contained even more microbial material, in particular chitin. Results therefore suggest that the admixture of microbial SOM is considerable in loess-paleosols and that differences in edaphic conditions (in particular slope position and soil moisture) and occurrence of wildfires are important for the long-term preservation of SOM. These should therefore be considered when interpreting biogeochemical proxies.status: publishe

Fossil redox-conditions influence organic matter composition in loess paleosols

International audienc

Impact of drainage and soil hydrology on sources and degradation of organic matter in tropical coastal podzols

In podzols important environmental issues converge, including dissolved organic matter (DOM) transport, DOM-metal binding, and carbon storage in the subsoil. Therefore, it is important to understand the formation and degradation of podzols in relation to (changes in) environmental conditions. For this purpose a Holocene barrier island with coastal sand dunes (Ilha Comprida, SE Brazil) was chosen as study area. The island is build-up of five geomorphic units that have different age (from >5000 to 325 y BP), vegetation (restinga ecosystems), soil hydrology (flat units or units with ridges and swales) and drainage (poorly drained, well-drained, and improved drainage). Representative profiles were studied for each geomorphic unit, resulting in 100 samples from A, E, B, and C horizons, from which soil organic matter (SOM) was isolated by alkaline extraction. To better understand carbon sources and dynamics, we additionally sampled litter from different vegetation types and DOM from various sources. The molecular composition of SOM, DOM and litter was analyzed with pyrolysis gas chromatography mass spectrometry (pyrolysis-GC/MS). Comparing the pyrolysates of all samples (DOM, SOM and litter) factor analysis demonstrated that the major difference in molecular composition (factor 1) was related to the contribution from DOM (phenol, acetic acid, benzofurans, pyridine, benzene and naphthalene) or in-situ root material (straight chain aliphatics and methoxyphenols from the biomacromolecules suberan and lignin, respectively). The contribution from DOM or roots was characteristic for a profile i.e. without much change with depth. Factor 2 reflected decomposition processes, and showed that the predominantly DOM-derived B horizons were relatively enriched in aromatics compared to DOM, indicating selective decay and/or selective precipitation. In geomorphic units with swales and ridges that received DOM via groundwater flow from the catchment area, the B horizon was predominantly DOM-derived; these profiles showed large differences in the contribution from black carbon (BC; (poly)aromatics), with the younger profiles showing a larger contribution from BC in precipitated DOM. B horizons with a relatively large contribution from in-situ root materials were found in well-drained soils and in some of the poorly drained soils without lateral groundwater flow from the catchment area, i.e., the flat geomorphic unit without ridges and swales. Microbial material (N-containing compounds and sugars) was associated with relatively recent SOM and with well-drained conditions at present. i.e., well-drained profiles, and profiles with improved drainage