Almacenamiento de carbono en sistemas agroforestales en los Llanos Orientales de Colombia / Carbon storage in agroforestry systems in Colombia's Eastern Plains

Introducción: Los cultivos de café, cacao y pasturas para la ganadería son actividades agropecuarias de interés económico en Colombia. Cuando estas actividades se desarrollan bajo sistemas agroforestales (SAF) promueven la conservación e incrementan la fijación de carbono y, por ende, la mitigación del cambio climático. Objetivo: El estudio estimó el almacenamiento de carbono en la biomasa aérea, necromasa y carbono orgánico del suelo bajo SAF con cacao (SAF cacao), SAF con café (café SAF), sistemas silvopastoriles (SSP) y bosque en el municipio de Mesetas, Meta (Colombia). Métodos: Se establecieron 44 parcelas de muestreo, en donde se tomaron medidas dasométricas a individuos con un diámetro del tronco a la altura del pecho (dap) ≥ 2.5 cm (latizales, fustales y fustales grandes), cuyos valores fueron transformados a carbono con modelos de biomasa y una fracción de carbono default. En los tres sistemas agropecuarios, se contó el número de árboles de cacao, café, plantas asociadas y se identificó el tipo de uso (maderable, alimento, combustión). Resultados: El almacenamiento de carbono presentó diferencias significativas (P < 0.0001) entre usos del suelo. La mayor acumulación se encontró en bosque, con 216.6 t C ha-1, superando en 59, 72 y 73 % a SAF cacao, SSP y SAF café, respectivamente. Fabaceae, Lauraceae y Primulaceae presentaron el mayor almacenamiento de carbono. En SAF cacao, la mayor acumulación de carbono fue encontrada en especies para alimento humano; en SAF café y SSP, el mayor almacenamiento fue presentado en las especies maderables. Conclusión: Estos resultados resaltan el potencial de almacenamiento de carbono en los sistemas productivos de mayor importancia en el departamento del Meta, lo cual es importante para el diseño de estrategias que permitan integrar acciones de mitigación de emisiones de gases de efecto invernadero y promover la economía campesina local.

Introduction: Coffee, cocoa crops and pastures for livestock are agricultural activities of economic interest in Colombia. When these activities are developed under agroforestry systems (AFS), they promote conservation and increase carbon fixation and, therefore, climate change mitigation. Objective: The study estimated carbon storage in aboveground biomass, necromass and soil organic carbon under SAF with cocoa (SAF cocoa), SAF with coffee (SAF coffee), silvopastoral systems (SPS) and forest in Mesetas, Meta (Colombia). Methods: Forty-four sampling plots were established, where dasometric measurements were taken from individuals with a trunk diameter at breast height (dbh) ≥ 2.5 cm (saplings, trees and large trees), whose values were transformed to carbon with biomass models and a default carbon fraction. In the three agricultural systems, the number of cocoa and coffee trees and associated plants was counted, and the type of use (timber, food, combustion) was identified. Results: Carbon storage showed significant differences (P < 0.0001) among land uses. The highest accumulation was found in forest, with 216.6 t C ha-1, exceeding in 59, 72 and 73 % to SAF cocoa, SSP and SAF coffee, respectively. The botanical families Fabaceae, Lauraceae and Primulaceae presented the greatest carbon storage. In SAF cocoa, the greatest accumulation of carbon was found in species for human food; in SAF coffee and SSP, the greatest storage was presented by timber species. Conclusion: These results highlight the potential for carbon storage in the most important productive systems in the Meta department, which is important for designing strategies that allow for integrating actions to mitigate greenhouse gas emissions and to promote the local peasant economy.

Dynamics of photosynthetic responses in 10 rubber tree (Hevea brasiliensis) clones in Colombian Amazon: Implications for breeding strategies.

The rubber tree [Hevea brasiliensis (Willd. Ex Adr. de Juss.) Muell.-Arg] is the main source of natural rubber in the world. However, in the Amazon region, its production is reduced by biotic and abiotic limitations, which have prompted breeding programs in order to identify desirable agronomic and physiological indicators. The objective of this study was to analyze the temporal dynamics of photosynthetic responses based on the parameters of leaf gas exchange and chlorophyll a fluorescence in 10 rubber tree clones during the immature phase (pre-tapping) in three large-scale clone trials, during daily cycles and under two climatic periods (dry and rainy) in the Caquetá region (Colombian Amazon). The variables A, LT, ΦPSII, ETR and qP were significantly higher in the dry period, where the highest values of PAR, AT and VPD were seen. In San Vicente del Caguán and Florencia, the highest averages were estimated for A, E and gs, as compared with Belén de los Andaquíes. In Florencia, the highest fluorescence parameters of chlorophyll a were recorded. At 9:00 h and 12:00 h, the highest means of A, E, ΦPSII and ETR were observed. The majority of the clones displayed the highest Fv/Fm mean (0.82-0.84) in the dry period. The clones FX 4098, FDR 4575, MDF 180, GU198 and FDR 5788 represent genotypes with the best photosynthetic performance (greater photosynthetic rates and better ability of the photosynthetic apparatus to capture, use and dissipate light energy). These desirable genotypes constitute a promising gene pool for expanding the genetic resource of rubber trees in the Colombian Amazon.

Photosynthesis limitations in cacao leaves under different agroforestry systems in the Colombian Amazon.

Cacao (Theobroma cacao L.) has traditionally been considered a crop that requires shade, and consequently it is implemented under agroforestry systems (AFs) in order to regulate the level of incident solar radiation. However, optimal shade levels for this tree crop may vary depending on the climate conditions of where it is grown. Here we analyzed the physiological performance of cacao under three different AFs in the Colombian Amazon that differed in solar radiation patterns: high (HPAR), medium (MPAR), or low (LPAR) mean daily incident radiation. The physiological performance was characterized using photosynthetic variables in leaves such as light- and CO2-response curves, chlorophyll a fluorescence parameters, and total chlorophyll and carotenoid contents, in conjunction with other leaf functional traits. Cacao trees exposed to HPAR showed an improved physiological performance as compared to those from the other two AFs. Compared to MPAR and LPAR, cacao trees in HPAR doubled the rate of net carbon assimilation and reached higher maximum rates of RuBisCO carboxylation and RuBP regeneration. Moreover, cacao trees in HPAR presented photoprotection mechanisms that avoided photoinhibition, which was accompanied by a greater non-photochemical quenching coefficient and biochemical and morphological adjustments (low chlorophyll but higher carotenoid contents and low specific leaf area) compared to cacao trees from the other AFs. Overall, our results show that, due to the high cloud cover in the Colombian Amazon, cacao plantations under conditions of sparse shade maximized their carbon use, showing an improved physiological performance as a result of higher photosynthetic rates and energy dissipation mechanisms. If the crop were managed with sparse shade, the paradigm that favors the cultivation of cacao under shade would be called into question in the Colombian Amazon and other regions with similar climatic conditions.

First typology of cacao (Theobroma cacao L.) systems in Colombian Amazonia, based on tree species richness, canopy structure and light availability.

AIM AND BACKGROUND: We present a typology of cacao agroforest systems in Colombian Amazonia. These systems had yet to be described in the literature, especially their potential in terms of biodiversity conservation. The systems studied are located in a post-conflict area, and a deforestation front in Colombian Amazonia. Cacao cropping systems are of key importance in Colombia: cacao plays a prime role in post conflict resolution, as cacao is a legal crop to replace illegal crops; cacao agroforests are expected to be a sustainable practice, promoting forest-friendly land use. MATERIAL AND METHODS: We worked in 50 x 2000 m2 agroforest plots, in Colombian Amazonia. A cluster analysis was used to build a typology based on 28 variables characterised in each plot, and related to diversity, composition, spatial structure and light availability for the cacao trees. We included variables related to light availability to evaluate the amount of transmitted radiation to the cacao trees in each type, and its suitability for cacao ecophysiological development. MAIN RESULTS: We identified 4 types of cacao agroforests based on differences concerning tree species diversity and the impact of canopy spatial structure on light availability for the cacao trees in the understorey. We found 127 tree species in the dataset, with some exclusive species in each type. We also found that 3 out of the 4 types identified displayed an erosion of tree species diversity. This reduction in shade tree species may have been linked to the desire to reduce shade, but we also found that all the types described were compatible with good ecophysiological development of the cacao trees. MAIN CONCLUSIONS AND PROSPECTS: Cacao agroforest systems may actually be achieving biodiversity conservation goals in Colombian Amazonia. One challenging prospect will be to monitor and encourage the conservation of tree species diversity in cacao agroforest systems during the development of these cropping systems, as a form of forest-friendly management enhancing sustainable peace building in Colombia.

Importancia cultural de vegetación arbórea en sistemas ganaderos del municipio de san vicente del caguán, colombia / Cultural significance of arboreous vegetation in livestock systems of the municipality of san vicente del caguan, colombia

El conocimiento local juega un papel importante en la identificación de especies arbóreas, que contribuyen a la formación de alternativas para sistemas ganaderos, en función a la conservación, la protección del ambiente y la economía de los productores. En la actualidad, se hace necesario conocer alternativas y beneficios para afrontar la variabilidad del clima, que afecta la producción ganadera. Es por ello, que el conocimiento de los productores ganaderos incide sobre la percepción y la toma de decisiones. En este sentido, el objetivo de este estudio fue determinar la importancia cultural de especies arbóreas en los sistemas ganaderos, por medio del conocimiento local. Se realizaron 57 encuestas, para el desarrollo de la metodología de índice de importancia cultural de las especies arbóreas. Se encontró, que las especies para sombra, son las de mayor preferencia; el segundo uso más frecuente es la implementación de árboles para la mitigación y la adaptación al cambio climático y, por último, especies de usos agrícolas. Además, se reconoció que las especies con mayor índice de importancia cultural (IIC) e intensidad de uso (IU) fue Zygia longifolia, con 3,21 IIC y 60% IU, respectivamente. Asimismo, se reconoció que el uso de especies para sombra son las de mayor predominancia, con 132 menciones y una diferencia significativa de 24 menciones, para cercas vivas. Este estudio permitió reconocer el conocimiento de los productores sobre el valor y el uso de las especies arbóreas y forrajeras, para determinar las especies con mayor importancia cultural.

Local knowledge plays an important role in the identification of tree species that contribute to the formation of alternatives to livestock systems in terms of conservation, protection of the environment and producers' economies. At present, it is necessary to know alternatives and benefits to face the variability of the climate that affects livestock production. This is why the knowledge of livestock producers affects the perception and decision making. In this sense, the objective was to determine the cultural importance of tree species in livestock systems through local knowledge. 57 surveys were carried out for the development of the methodology of index of cultural importance of the tree species. It was found that the species for shade are the most preferred; the second most frequent use is the implementation of trees for the mitigation and adaptation to the climatic change and last species of agricultural uses. In addition, it was recognized that the species with the highest cultural importance index (CIU) and intensity of use (UI) were Zygia longifolia with 3.21 IIC and 60% IU, respectively. Also, it was recognized that the use of species for shade are the most predominant with 132 mentions and a significant difference of 24 mentions for live fences. This study allowed to recognize the knowledge of the producers on the value and use of the tree species and fodder species to determine the species with greater cultural importance.

El consumo de carne como tendencia cultural en la Amazonía colombiana / Meat consumption as a cultural trend in the Colombian Amazon basin / EO consumo de carne como uma tendência cultural na Amazônia colombiana

La identificación de tendencias en el consumo de carne resulta indispensable para los planes de establecimiento y asesoría de los sistemas de producción zootécnica, especialmente en zonas de alto impacto ambiental como la Amazonía colombiana. El estudio presentado en este artículo identifica las tendencias globales de consumo de carne, a partir de una muestra poblacional obtenida en la ciudad Amazónica de Florencia, capital del departamento del Caquetá. En el mismo, se concluyó un bajo interés por aspectos relacionados con adecuadas condiciones de manejo y sacrifico de animales, a pesar de considerar este factor como condicionante de la calidad del producto; entre otros resultados, se identifica claramente que el consumo de carne, principalmente de res, obedece a cuestiones culturales y sociales, y no a las características organolépticas del producto o su precio. Con relación al consumo de carne de monte, a partir del análisis de preferencia y precio, en el marco de la inexistencia de zoocriaderos en lo zona o cerca de ella, se deduce la ilegalidad de su proveniencia, y se concluye un desconocimiento pleno de los riegos ambientales, zoonóticos y legales, que acarrea este delito.

Identifying trends in meat consumption is indispensable for establishing plans and advice to animal production systems, especially in areas of high environmental impact such as the Colombian Amazon basin. This study identifies global trends in meat consumption from a sample obtained in the Amazonian city of Florencia, capital of Caquetá province. Lack of interest was observed among the population about proper management conditions and slaughter of animals, despite they considered these factors to be determinant of product quality. The study clearly identified that meat consumption, especially beef, depends more on cultural and social issues than price or organoleptic characteristics of the product. From a preference and price analysis, and considering the lack of wild animal farming in or near the area, we assume all game meat consumed in the area is of illegal origin. Consumers of wild meat are not aware of the environmental, zoonotic and legal risks associated with this offense.

Identificar tendências do consumo de carne é essencial para os quadros de pessoal e conselhos de sistemas de produção animal, especialmente em áreas de alto impacto ambiental, como a Amazônia colombiana. O estudo apresentado neste artigo identifica as tendências mundiais em consumo de carne a partir de uma amostra da população obtida na cidade amazônica de Florença, capital do departamento de Caquetá. Nos mesmos aspectos de juro baixas condições adequadas de manejo e abate de animais, apesar de considerar este fator como determinante da qualidade do produto é concluída; entre outros resultados, identifica claramente que o consumo de carne, especialmente carne, devido a questões culturais e sociais, e não com as características organolépticas do produto ou seu preço. No que diz respeito ao consumo de carne de animais selvagens, a partir da análise de preferência e preço, no contexto da ausência de zoocriaderos na ou perto da área a ele, o ilícita do seu proveniência é claro, e cheio de ignorância, conclui-se ambiental, zoonótico e riscos legais que implica este crime.