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This project intends to use the Mount Denali ice core archive to develop the most comprehensive suite of North Pacific fire and summer climate proxy records since about 2500 years before present. Wildfire is a key component of summer climate in the North Pacific where wildfires are projected to increase with continued summer warming. Studies that combine paleorecords of summer climate and wildfire are therefore critically needed, especially in the North Pacific region where fire recurrence rate and decadal-to-centennial scale climate fluctuations occur over longer time periods than are covered by direct observations. The goal of the proposed research is to improve our understanding of relationships between summertime climate and wildfire activity, focusing especially on the Medieval Climate Anomaly (MCA), when regional temperatures were perhaps as warm as the 20th century. Recent advances now permit the measurement of new fire-related (pyrogenic) compounds in ice cores, enabling the development of a robust fire record capable of rigorous comparison with regional paleoclimate reconstructions.

La variabilidad anatómica presente en los cerebros de pacientes limita la realización de análisis estadísticos acerca de la presencia o ausencia de una patología. En este artículo, presentamos una aproximación para la clasificación de imágenes de Resonancia Magnética (MR) cerebral de sujetos sanos y afectados por una patología. El enfoque se basa en un mapa de saliencia, el cual extrae regiones de cambio relativo en tres diferentes dimensiones: intensidad, orientación y bordes. Las regiones de interés obtenidas se utilizan como patrones para la clasificación de sujetos utilizando máquinas de vectores de soporte. El desempeño de la estrategia propuesta fue evaluado en un conjunto de 198 imágenes de MR extraídas de la base de datos OASIS y divididas en cuatro grupos, reportando una tasa de precisión promedio de y una tasa de error igual (Equal Error Rate) promedio de .

ABSTRACT : We developed a three-component model to evaluate the present and future hydrological behavior of Ayapel Cienaga under different scenarios of climate variability and human intervention associated with fishing and mining activities and the maintenance of levees. We calibrated the water balance with historical information on hydrological variables, water levels, stream discharges, fishing activities and gold mining records in the period 1985-2015. We use autoregressive statistical models to project climate scenarios that consider extreme variations in mean monthly rainfall, ENSO activity, temperature increases of 2°C, and levee breaks along the Cauca River. In addition, we incorporated two dynamic of systems models of bocachico fish population and mercury accumulation in the Cienaga. The simulations indicate that the Cienaga levels can be affected by extreme changes in rainfall associated with ENSO. The model estimates the fraction of water that could enter from the Cauca River due to levee breaks. Furthermore, using a fish dynamic population we could project the population and catch of bocachico. Finally, the mercury balance model due to mining in the region help to estimate mercury concentrations in water, fish and aquatic macrophytes matrices. This model offers a tool for management and decision-making in ecohydrological aspects of the Cienaga under different climate change scenarios. ; RESUMEN : Desarrollamos un modelo con tres componentes para evaluar el comportamiento hidrológico presente y futuro de La Ciénaga de Ayapel bajo diferentes escenarios de variabilidad climática e intervención humana asociada con pesca y minería y el mantenimiento de diques. Calibramos el balance hídrico con información histórica sobre variables hidrológicas, niveles de agua, descargas de arroyos, actividades de pesca y registros de extracción de oro en el período 1985-2015. Utilizamos modelos estadísticos autorregresivos para proyectar escenarios climáticos que consideran variaciones extremas en la precipitación media ...

At nowadays, the operational control of energy performance indicators based on the equivalent occupation method plays a fundamental role in the rational use of energy for the hotel sector, since it allows in a competitive way to comply with the quality of the service offered by the company in terms of the thermal comfort of the occupants, minimizing the environmental impact. Within the framework of the energy diagnosis and implementation of the program of efficient energy management under ISO 50001: 2011, based on the method of equivalent occupation for a hotel company on the Colombian Caribbean coast, the line base, target line by 2015, determining performance control indicators such as accumulative trend and base efficiency index 100, to identify potential savings. From the diagnosis, 9.11% of energy savings were obtained by operational control. Through the implementation of corrective action plans, such as the shutdown of unnecessary equipment in the company, installation of LED lighting modules, the configuration of thermostats, in addition to training and sensitization to staff, and reactive energy control in the hotel effective savings were achieved around 8% of primary energy consumption by 2016.

The exigencies as soon as to competitiveness and productivity have influenced in the energetic consumption and the demand of electrical energy in Colombia, reason why at the present time it is of much interest and utility to have access to tools or valid models to reach greater knowledge in which related to the possible future projections. Next, the results of a quantitative study are presented that through the analysis of data collected between 2007 and 2017 that made possible the construction of a multiple linear regression model to estimate the demand of electric energy. These types of instruments currently originate as alternatives to promote management strategies in the energy field in the country. The final results allow to visualize an estimated figure for the next periods which will serve to contrast with the official results and to generate from this information possible lines of intervention in different organisms. ; Las exigencias en cuanto a competitividad y productividad han influido en el consumo energético y la demanda de energía eléctrica en Colombia, por lo que en la actualidad es de mucho interés y utilidad tener acceso a herramientas o modelos válidos para alcanzar un mayor conocimiento en lo relacionado con Las posibles proyecciones futuras. A continuación, se presentan los resultados de un estudio cuantitativo que a través del análisis de los datos recopilados entre 2007 y 2017 eso hizo posible la construcción de un modelo de regresión lineal múltiple para estimar la demanda de energía eléctrica. Este tipo de instrumentos actualmente se originan como alternativas para promover estrategias de gestión en el campo de la energía en el país. Los resultados finales permiten visualizar una cifra estimada para el Próximos períodos que servirán para contrastar con los resultados oficiales y generar a partir de esta información posibles líneas de intervención en diferentes organismos.

* File name: README.md * Authors: Zikun Mao, Xugao Wang * Other contributors: Fons van der Plas, Adriana Corrales, Kristina J. Anderson-Teixeira, Norman A. Bourg, Chengjin Chu, Zhanqing Hao, Guangze Jin, Juyu Lian, Fei Lin, Buhang Li, Wenqi Luo, William J. McShea, Jonathan A. Myers, Guochun Shen, Xihua Wang, En-Rong Yan, Ji Ye, Wanhui Ye, Zuoqiang Yuan * Date created: 2022-11-20 * Date modified: 2024-05-13 ## Dataset Attribution and Usage * Dataset Title: "Scale-dependent diversity–biomass relationships can be driven by tree mycorrhizal association and soil fertility" * Persistent Identifier: [https://doi.org/10.5061/dryad.612jm646w](https://doi.org/10.5061/dryad.612jm646w) * Dataset Contributors: * Creators: Zikun Mao, Fons van der Plas, Adriana Corrales, Kristina J. Anderson-Teixeira, Norman A. Bourg, Chengjin Chu, Zhanqing Hao, Guangze Jin, Juyu Lian, Fei Lin, Buhang Li, Wenqi Luo, William J. McShea, Jonathan A. Myers, Guochun Shen, Xihua Wang, En-Rong Yan, Ji Ye, Wanhui Ye, Zuoqiang Yuan, Xugao Wang * License: Use of these data is covered by the following license: * Title: CC0 1.0 Universal (CC0 1.0) * Specification: [https://creativecommons.org/publicdomain/zero/1.0/](https://creativecommons.org/publicdomain/zero/1.0/); the authors respectfully request to be contacted by researchers interested in the re-use of these data so that the possibility of collaboration can be discussed. * Suggested Citations: * Dataset citation: > Mao, Z., F. van der Plas, A. Corrales, K. J. Anderson-Teixeira, N. A. Bourg, C. Chu, Z. Hao, G. Jin, J. Lian, F. Lin, et al. 2023. Scale-dependent diversity–biomass relationships can be driven by tree mycorrhizal association and soil fertility. Dryad, Dataset, [https://doi.org/10.5061/dryad.612jm646w](https://doi.org/10.5061/dryad.612jm646w) * Corresponding publication: > Mao, Z., F. van der Plas, A. Corrales, K. J. Anderson-Teixeira, N. A. Bourg, C. Chu, Z. Hao, G. Jin, J. Lian, F. Lin, et al. 2023. Scale-dependent diversity–biomass relationships can be driven by tree mycorrhizal association and soil fertility. Ecological Monographs, 93: e1568 ## Contact Information * Name: Zikun Mao * Affiliations: CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China * ORCID ID: [https://orcid.org/0000-0002-7035-9129](https://orcid.org/0000-0002-7035-9129) * Email: [maozikun@iae.ac.cn](mailto:maozikun@iae.ac.cn) * Alternate Email: [maozikun15@mails.ucas.ac.cn](mailto:maozikun15@mails.ucas.ac.cn) * Alternate Email 2: [maozikun15@126.com](mailto:maozikun15@126.com) * Alternative Contact Name: Xugao Wang * Affiliations: CAS Key Laboratory of Forest Ecology and Management, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China * ORCID ID: [https://orcid.org/0000-0003-1207-8852](https://orcid.org/0000-0003-1207-8852) * Email: [wangxg@iae.ac.cn](mailto:wangxg@iae.ac.cn) --- # Additional Dataset Metadata ## Acknowledgements * Funding sources: This work was financially supported by the National Natural Science Foundation of China (Grant 31961133027), the National Key Research and Development Program of China (2022YFF1300501), the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (Grant ZDBS-LY-DQC019), the K. C. Wong Education Foundation, the General Program of China Postdoctoral Science Foundation (2021M703397), the Special Research Assistant Project of Chinese Academy of Sciences (2022000056), and the Major Program of Institute of Applied Ecology, Chinese Academy of Science (IAEMP202201). Chengjin Chu was funded by the National Natural Science Foundation of China (31925027). Funding for the data collections was provided by many organizations, including the Smithsonian Institution, the National Science Foundation (DEB 1557094), the National Zoological Park, the HSBC Climate Partnership, the International Center for Advanced Renewable Energy and Sustainability (I-CARES) at Washington University in St. Louis and the Tyson Research Center # Methodological Information * Methods of data collection/generation: see manuscript for details --- # Data and File Overview ## Summary Metrics * File count: 6 * Total file size: 42.4 MB * Range of individual file sizes: 12.3 KB - 41.5 MB * File formats: .RData, .R, .xlsx ## Table of Contents * 1\. Data source to run the R code.RData * 2\. Codispersion null model analysis.R * 3\. Generalized least squares model analysis.R * 4\. Structural equation modeling analysis.R * Observed data source.xlsx * Mycorrhizal types.xlsx Note: * These datasets contain the data for seven forest mega-plots, i.e., FL: Fenglin; TRC: Tyson Research Center; CBS: Changbaishan; SCBI: Smithsonian Conservation Biology Institute; TTS: Tiantongshan; DHS: Dinghushan; HSD: Heishiding * The authors respectfully request to be contacted by researchers interested in the datasets of other three scales (i.e., 10-m, 50-m, and 100-m) so that the possibility of collaboration can be discussed ## Setup * Recommended software/tools: R version 3.6.3 ([https://www.r-project.org/](https://www.r-project.org/)) for .RData and .R files; Microsoft Office EXCEL 2013 for .xlsx files --- * Relationship between data files * To run the R codes in the three .R files, you need to first open the R software and then load the R workspace "1. Data source to run the R code.RData" * The .xlsx file "Observed data source.xlsx" contains all the observed datasets in the .RData file "1. Data source to run the R code.RData" --- # File/Folder Details ## Details for: 1. Data source to run the R code.RData * General description: a .RData file containing the observed datasets and null model datasets at the 20-m scale to run the three analyses, i.e., codispersion null model analysis (codes in "2. Codispersion null model analysis.R"), generalized least squares model analysis ("3. Generalized least squares model analysis.R"), and structural equation modeling analysis ("4. Structural equation modeling analysis.R") * Format(s): .RData * Size(s): 41.5 MB * Contains: 14 datasets * Description for the 14 datasets: * Running "ls()" in the R software to see the names of these 14 datasets * The names of these 14 datasets are: "FL", "FL_Null_20", "TRC", "TRC_Null_20", "CBS", "CBS_Null_20", "SCBI", "SCBI_Null_20", "DHS", "DHS_Null_20", "TTS", "TTS_Null_20", "HSD", "HSD_Null_20" * FL: R data with "data.frame" format; the observed data of each 20m * 20m quadrat for FL plot * FL_Null_20: R data with "list" format containing 199 "data.frame" subdata; the null model data to conduct the codispersion null model analysis for FL plot * TRC: R data with "data.frame" format; the observed data of each 20m * 20m quadrat for TRC plot * TRC_Null_20: R data with "list" format containing 199 "data.frame" subdata; the null model data to conduct the codispersion null model analysis for TRC plot * CBS: R data with "data.frame" format; the observed data of each 20m * 20m quadrat for CBS plot * CBS_Null_20: R data with "list" format containing 199 "data.frame" subdata; the null model data to conduct the codispersion null model analysis for CBS plot * SCBI: R data with "data.frame" format; the observed data of each 20m * 20m quadrat for SCBI plot * SCBI_Null_20: R data with "list" format containing 199 "data.frame" subdata; the null model data to conduct the codispersion null model analysis for SCBI plot * DHS: R data with "data.frame" format; the observed data of each 20m * 20m quadrat for DHS plot * DHS_Null_20: R data with "list" format containing 199 "data.frame" subdata; the null model to conduct the codispersion null model analysis for DHS plot * TTS: R data with "data.frame" format; the observed data of each 20m * 20m quadrat for TTS plot * TTS_Null_20: R data with "list" format containing 199 "data.frame" subdata; the null model to conduct the codispersion null model analysis for TTS plot * HSD: R data with "data.frame" format; the observed data of each 20m * 20m quadrat for HSD plot * HSD_Null_20: R data with "list" format containing 199 "data.frame" subdata; the null model to conduct the codispersion null model analysis for HSD plot * Variables in these datasets: * Quad.num: The serial number of 20m * 20m quadrats * gx, gy: The coordinate of each 20m × 20m quadrat (m) * AGB.all: Aboveground biomass (AGB) of all trees in one quadrat (Mg/ha) * AGB.AM: AGB of AM (i.e., arbuscular mycorrhizal) trees in one quadrat (Mg/ha) * AGB.EM: AGB of EM (i.e., ectomycorrhizal) trees in one quadrat (Mg/ha) * SpNum.all: Tree species richness or number of tree species with > 1 individuals in one quadrat * SpNum.AM: AM tree species richness or number of AM tree species with > 1 individuals in one quadrat * SpNum.EM: EM tree species richness or number of EM tree species with > 1 individuals in one quadrat * Num.all: The number of tree individuals in one quadrat * Num.AM: The number of AM tree individuals in one quadrat * Num.EM: The number of EM tree individuals in one quadrat * AMdomi: AM tree dominance in one quadrat quantified using the proportion of AM tree individuals * EMdomi: EM tree dominance in one quadrat quantified using the proportion of EM tree AGB * Soil.PC1: Soil fertility index from the first principal component of the principal component analysis (only for observed datasets) * Soil.PC2: Soil fertility index from the second principal component of the principal component analysis (only for observed datasets) * Soil: Soil fertility index from the first principal component (for FL, TRC, CBS, SCBI, DHS plots) or the second principal component (for TTS and HSD plots) of the principal component analysis (only for null model datasets) ## Details for: 2. Codispersion null model analysis.R * Description: a .R file containing all codes to conduct our codispersion null model analyses (see the Method section in the manuscript for details) * Format(s): .R * Size(s): 80 KB * Note: * Please open this file using R software * All necessary explanations for the "codispersion null model analysis" code can be found in the text after the "#" label in this .R file * Very important note: anyone who want to use this code to run the codispersion analysis, please cite the Buckley's paper in 2016 ([https://doi.org/10.1111/nph.13934](https://doi.org/10.1111/nph.13934)). ## Details for: 3. Generalized least squares model analysis.R * Description: a .R file containing all codes to conduct our generalized least squares model analysis (see the Method section in the manuscript for details) * Format(s): .R * Size(s): 12.3 KB * Note: * Please open this file using R software * All necessary explanations for the "generalized least squares model analysis" code can be found in the text after the "#" label in this .R file ## Details for: 4. Structural equation modeling analysis.R * Description: a .R file containing all codes to conduct our structural equation modeling analysis (see the Method section in the manuscript for details) * Format(s): .R * Size(s): 41.0 KB * Note: * Please open this file using R software * All necessary explanations for the "structural equation modeling analysis" code can be found in the text after the "#" label in this .R file ## Details for: Observed data source.xlsx * Description: a .xlsx file containing all the observed datasets of each 20m * 20m quadrats for the seven forests * Format(s): .xlsx * Size(s): 657 KB * Contents: 9 sheets * Description for each sheet: * Article information: listing the the article title, authors, and journal name * Column name: listing and explaining each column name in this dataset * Fenglin: the observed dataset containing 16 columns for FL plot * TRC: the observed dataset containing 16 columns for TRC plot * Changbaishan: the observed dataset containing 16 columns for CBS plot * SCBI: the observed dataset containing 16 columns for SCBI plot * Dinghushan: the observed dataset containing 16 columns for DHS plot * Tiantongshan: the observed dataset containing 16 columns for TTS plot * Heishiding: the observed dataset containing 16 columns for HSD plot * Note: please see the sheet "Column name" in this .xlsx file for the explanation of each column ## Details for: Mycorrhizal types.xlsx * Description: a .xlsx file showing the mycorrhizal type and the referred literature of each tree species * Format(s): .xlsx * Size(s): 70.9 KB * Contents: 10 sheets * Description for each sheet: * Article information: listing the the article title, authors, journal name, and abbreviation of mycorrhizal association * References: listing all the references (in total 49 items) used to classify the mycorrhizal type of studied species * Mycorrhizal associations: listing the basic information (including Family, Genera, and Species name), mycorrhizal classification, and the referred literatures for each tree species Column "Family": The Family name of each species Column "Genera": The Genera name of each species Column "Species": The Species name of each species Column "Mycorrhizal_type": Mycorrhizal types of each species to conduct our primary analyses, but for the species in red font, their mycorrhizal type was reassigned in the robustness test (see the note in the brackets for details) Column "Mycorrhizal_type_detailed": more detailed mycorrhizal types for each tree species Column "Reference and Note": referred literature and the detailed notes for each tree species * Fenglin: the mycorrhizal type and the referred literature of each tree species in FL plot * TRC: the mycorrhizal type and the referred literature of each tree species in TRC plot * Changbaishan: the mycorrhizal type and the referred literature of each tree species in CBS plot * SCBI: the mycorrhizal type and the referred literature of each tree species in SCBI plot * Dinghushan: the mycorrhizal type and the referred literature of each tree species in DHS plot * Tiantongshan: the mycorrhizal type and the referred literature of each tree species in TTS plot * Heishiding: the mycorrhizal type and the referred literature of each tree species in HSD plot * Access Information --- * To generate these datasets, we used the raw census and soil data of the ForestGEO network that can only be shared on request because most PIs have not made them publicly available. Forest census data from the ForestGEO data portal can be obtained by filling out the online Data RequestForm ([http://ctfs.si.edu/datarequest/index.php/main/plotdata](http://ctfs.si.edu/datarequest/index.php/main/plotdata)). Soil data are available to qualified researchers from ForestGEO network by contacting the mega-plot PIs ([https://forestgeo.si.edu/meet-team/principal-investigators](https://forestgeo.si.edu/meet-team/principal-investigators)). --- END OF README Diversity–biomass relationships (DBRs) often vary with spatial scale in terrestrial ecosystems, but the mechanisms driving these scale-dependent patterns remain unclear, especially for highly heterogeneous forest ecosystems. This study explores how mutualistic associations between trees and different mycorrhizal fungi (i.e., arbuscular mycorrhizal (AM) vs. ectomycorrhizal (EM) association) modulate scale-dependent DBRs. We hypothesized that in soil-heterogeneous forests with a mixture of AM and EM tree species, (i) AM and EM tree species respond in contrasting ways (i.e., positively vs. negatively respectively) to increasing soil fertility, (ii) AM tree dominance contributes to higher tree diversity and EM tree dominance contributes to greater standing biomass and that as a result, (iii) mycorrhizal associations exert an overall negative effect on DBRs across spatial scales. To empirically test these hypotheses, we collected detailed tree distribution and soil information (nitrogen, phosphorus, organic matter, pH, etc.) from seven temperate and subtropical AM-EM mixed forest mega-plots (16–50 ha). Using spatial codispersion null model and structural equation modeling, we identified the relationships among AM or EM tree dominance, soil fertility, tree species diversity and biomass, and thus DBRs across 0.01–1 ha scales. We found first evidence overall supporting the above three hypotheses in these AM-EM mixed forests: (i) In most forests, with increasing soil fertility tree communities changed from EM-dominated to AM-dominated. (ii) Increasing AM tree dominance had an overall positive effect on tree diversity and a negative effect on biomass, even after controlling for soil fertility and number of trees. Together, (iii) the changes in mycorrhizal dominance along soil fertility gradients weakened the positive DBR observed at 0.01–0.04 ha scales in nearly all forests and drove negative DBRs at 0.25–1 ha scales in four out of seven forests. Hence, this study highlights a soil-related mycorrhizal dominance mechanism that could partly explain why in many natural forests, biodiversity-ecosystem functioning (BEF) relationships shift from positive to negative with increasing spatial scale. See the "Materials and Methods" section in the manuscript for details.

The prospective of Colombia’s energy demand will be defined by economic, social, cultural and political phenomena. Modeling the factors that determine demand can be broadly divided into quantitative and qualitative. The quantitative phenomena, demography, energy efficiency and the direct consumption of fuels; qualitative effects are specific conditions, which are defined within each scenario as variables that will have effects on quantitative phenomena. In the baseline scenario, the transportation sector is expected to remain as the largest representative of Colombia’s energy demand, although its participation in the year 2050 will be reduced by approximately 7%. The residential sector will have a reduced growth supported by the law 1715 that will increase distributed generation and implement more efficient lighting systems. A scenario focused on energy diversification shows a reduction in demand since the short term. Transport sector is maintained with similar behaviors in all scenarios as the goods transport networks keep the same.

In this study, the Colombian electricity market, its regulation and its current tariff scheme was examined. Here, the operation of the electricity system and its value chain are described in detail. Future scenarios of supply and demand are also shown. The study presents a description of the legal incentives given by the government for the promotion of renewable energies, and strategic aspects and recommendations for the development of solar photovoltaic (PV) industry in Colombia were identified and formulated. In particular, strategies for collaboration between Colombia and Germany, which is a leader in the PV industry. The report presents an overview of solar PV systems markets worldwide and in Colombia. Regarding the solar market in Colombia, not only the historical development of the PV industry in the country is explained, but also the solar radiation in the whole country is shown. In the same way, this study shows a description of the most common alternatives for the electrification in off-grid areas and an enumeration of drivers and barriers for the development of the PV industry in the country.

The SST is one of the determining elements of the smart grid since it has the functionalities of a conventional transformer and allows an appropriate integration of distributed generation sources, loads, and energy storage devices with the traditional power grid. ; The interest in updating electrical networks and the possibility of having power semiconductor devices with better features (e.g., reliability and efficiency) have encouraged the production of elements, such as a Solid-State Transformer (SST). The SST is one of the determining elements of the smart grid since it has the functionalities of a conventional transformer and allows an appropriate integration of distributed generation sources, loads, and energy storage devices with the traditional power grid, in addition to having system functionality advantages such as unity power factor, mitigation of sags and swells, improving system efficiency and quality, and allowing a bidirectional flow of power. For this reason, the SST could replace the traditional transformer, considering the advantages it offers functional and physicals (less weight and volume). The intelligent energy management of an SST in a smart grid is feasible through the regulation of the power flow in its central device so-called Dual Active Bridge (DAB), which due to its topology (two half-bridge and a high-frequency link) make possible the bidirectionally on the power flow and permit the interconnection of renewable sources and other elements dc into a smart grid, and that in this way the advantages of SST can be made available within a power system. Hence, this work focuses on proposing a current controller based on Proportional-Integral (PI) passivity that regulates the power flow bidirectionally in a DAB. The proposed controller guarantees the system’s stability in a closed-loop, maintaining its passive properties. In addition, this controller preserves the simplicity of a PI control with high performance and robustness, where its control law is simple and does not depend on the ...

ABSTRACT : This research was carried out in the Porce river basin, Antioquia (Colombia) with nine coffee growing families in charge of conventional systems and in transition to the organic production of coffee. The farms were characterized from an agroecological perspective, while evaluating the social, economic and technical-productive dimensions. It was detected that the two main threats faced by small farmers in this area are climatic variability and fluctuations in coffee prices. Using the RIH Risk Index methodology, a set of indicators was proposed to reflect the vulnerability and the response capacity of these families. ; RESUMEN : En esta investigación se llevó a cabo en la cuenca del río Porce, Antioquia, Colombia con nueve familias de pequeños caficultores convencionales y en transición a la producción orgánica. Los caficultores fueron caracterizados desde la perspectiva agroecológica, evaluando las dimensiones sociales, económicas y técnico-productivas. Se detectó dos principales amenazas que enfrentan los pequeños caficultores de esta zona son la variabilidad climática y las fluctuaciones de los precios del café. Utilizando la metodología de Índice de Riesgo IHR, se propuso un conjunto de indicadores que reflejaran la vulnerabilidad y la capacidad de respuesta de estas familias. ; COL0088881