Browsing by Autor "Monika Schneider"

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Agroecosystem resilience and farmers’ perceptions of climate change impacts on cocoa farms in Alto Beni, Bolivia
(Cambridge University Press, 2013) Johanna Jacobi; Monika Schneider; Patrick Bottazzi; Maria Isabel Pillco; Patricia Calizaya; Stephan Rist
Abstract Cocoa-based small-scale agriculture is the most important source of income for most farming families in the region of Alto Beni in the sub-humid foothills of the Andes. Cocoa is grown in cultivation systems of varying ecological complexity. The plantations are highly susceptible to climate change impacts. Local cocoa producers mention heat waves, droughts, floods and plant diseases as the main impacts affecting plants and working conditions, and they associate these impacts with global climate change. From a sustainable regional development point of view, cocoa farms need to become more resilient in order to cope with the climate change related effects that are putting cocoa-based livelihoods at risk. This study assesses agroecosystem resilience under three different cocoa cultivation systems (successional agroforestry, simple agroforestry and common practice monocultures). In a first step, farmers’ perceptions of climate change impacts were assessed and eight indicators of agroecological resilience were derived in a transdisciplinary process (focus groups and workshop) based on farmers’ and scientists’ knowledge. These indicators (soil organic matter, depth of Ah horizon, soil bulk density, tree species diversity, crop varieties diversity, ant species diversity, cocoa yields and infestation of cocoa trees with Moniliophthora perniciosa ) were then surveyed on 15 cocoa farms and compared for the three different cultivation systems. Parts of the socio-economic aspects of resilience were covered by evaluating the role of cocoa cooperatives and organic certification in transitioning to more resilient cocoa farms (interviews with 15 cocoa farmers combined with five expert interviews). Agroecosystem resilience was higher under the two agroforestry systems than under common practice monoculture, especially under successional agroforestry. Both agroforestry systems achieved higher cocoa yields than common practice monoculture due to agroforestry farmers’ enhanced knowledge regarding cocoa cultivation. Knowledge sharing was promoted by local organizations facilitating organic certification. These organizations were thus found to enhance the social process of farmers’ integration into cooperatives and their reorientation toward organic principles and diversified agroforestry.
Building Farm Resilience in a Changing Climate: Challenges, Potentials, and Ways Forward for Smallholder Cocoa Production in Bolivia
(2016) Johanna Jacobi; Patrick Bottazzi; Maria Isabel Pillco; Monika Schneider; Stephan Rist
Cacao agroforestry systems have higher return on labor compared to full-sun monocultures
(Springer Science+Business Media, 2016) Laura Armengot; Pietro Barbieri; Christian Andrès; Joachim Milz; Monika Schneider
Cadmium uptake by cocoa trees in agroforestry and monoculture systems under conventional and organic management
(Elsevier BV, 2016) Anja Gramlich; Susan Tandy; Christian Andrès; Jorge Paniagua; Laura Armengot; Monika Schneider; Rainer Schulin
Carbon stocks, tree diversity, and the role of organic certification in different cocoa production systems in Alto Beni, Bolivia
(Springer Science+Business Media, 2013) Johanna Jacobi; Christian Andrès; Monika Schneider; Maria Isabel Pillco; Patricia Calizaya; Stephan Rist
COCOA AND TOTAL SYSTEM YIELDS OF ORGANIC AND CONVENTIONAL AGROFORESTRY VS. MONOCULTURE SYSTEMS IN A LONG-TERM FIELD TRIAL IN BOLIVIA
(Cambridge University Press, 2016) Monika Schneider; Christian Andrès; Germán Trujillo; Francisco Alcón; Patricia Amurrio; Eucebio Perez; Franco Weibel; Joaquin Milz
SUMMARY Cocoa ( Theobroma cacao L.) is produced in systems of varying complexity ranging from monoculture with temporary shade to highly diverse agroforests. Producers have to weigh high cocoa yields in the short to medium term in monocultures against higher total system yields in the short term and sustainable production systems in the long term in conjunction with ecosystem services in agroforestry systems (AFs). More long-term data on the comparative agronomic, economic and ecological performance of differently managed cocoa production systems is required to make sound recommendations to farmers. This paper describes the only long-term field trial worldwide comparing different cocoa production systems under conventional and organic management. The factors (i) crop diversity (monoculture vs. agroforestry), (ii) management practice (conventional vs. organic) and (iii) cultivar are being tested in a full-factorial, randomized complete block design with four replications. First, results showed significantly faster development of trunk circumferences in monocultures (+21%) compared to AFs. Cocoa yields were 47% lower in the organic compared to the conventional monoculture. In the AFs, however, the organic–conventional yield gap was less pronounced (−16%) and statistically insignificant. The cumulative yields of all products harvested were significantly higher in the AFs (+161%) compared to the monocultures. The productivity of cocoa by-crops in AFs may contribute to local food security and risk distribution in smallholder contexts.
Competitive yields in organic and agroforestry cacao cropping systems: results from 15 years of a long-term systems comparison trial in Bolivia
(Springer Science+Business Media, 2025) Johanna Rüegg; Stéphane Saj; Ulf Schneidewind; Joachim Milz; Monika Schneider; Laura Armengot
Abstract Cacao production is facing challenges of low productivity due to low soil fertility and climate change. Agroforestry and organic farming are potential sustainable and climate-resilient alternatives, but they are often associated with lower yields compared to monocultures and conventional farming. Despite their potential, empirical data on the long-term productivity of cacao cultivated in complex agroforestry systems and under organic management remains limited. Expanding this evidence base is essential to inform the development of agricultural practices and policies that advance environmental sustainability and food security. To fill this gap, we present 15 years (2008–2022) of data on cacao production and associated crops of a unique long-term trial comparing five cacao cropping systems in Bolivia: organically and conventionally managed monocultures, diverse agroforestry systems under organic and conventional management, and successional agroforestry systems without external inputs. We collected data on yields along with detailed information on the design and agronomic management from the beginning of the trial. All systems achieved competitive cacao yields in the mature phase. Organic and conventional systems had similar cacao yields, while agroforestry systems reached 56% of monoculture yields. Total system yields of the agroforestry systems were up to 6.9 times higher than monocultures. In the successional agroforestry, 22 crops were harvested, with short life cycle crops contributing to one-third of total production. This study shows that staple food crops and fruit trees as well as high-value crops (coffee, ginger, curcuma) can be successfully combined with cacao, and that agroforestry designs can be adapted over time by adding or eliminating crops to meet new goals or market opportunities. Extensive research has highlighted the positive contributions of agroforestry and organic farming to the delivery of ecosystem services. This study provides empirical evidence that it is possible to design and implement systems that reconcile environmental sustainability with productive performance.
Effects of environmental variables and foliar traits on the transpiration rate of cocoa (Theobroma cacao L.) under different cultivation systems
(Springer Science+Business Media, 2020) Francisco Saavedra; Ernesto Jordan Peña; Monika Schneider; Kazuya Naoki
Effects of pruning on flowering and yields of Cacao Nacional Boliviano
(Springer Science+Business Media, 2025) Chigusa Keller; Johanna Rüegg; Consuelo Campos Campos; Edwin Ontiveros Loza; Chloé Durot; Joachim Milz; Monika Schneider; Stéphane Saj
Abstract Cacao Nacional Boliviano (CNB), the native cacao germplasm group in the Bolivian Amazon region, possesses distinct morphological, genetic, phenological and organoleptic characteristics. It is highly sought after in the global fine-flavour chocolate market, and has importance for conservation of cacao genetic diversity. However, CNB cultivation is minor and yield levels low. Aiming to develop profitable CNB cultivation practices adapted to its distinct phenology and genetic basis, we compared parameters on CNB flowering, yields, biomass and harvesting effort in three agricultural systems with and without pruning and varying management intensity: agroforestry with pruning (AF), underplanted secondary forest with (SFwP), and without pruning (SFnP). Repeated measures linear mixed models using Restricted Maximum Likelihood were applied for statistical analysis. While AF and SFnP yielded 127.6 ± 21.4 kg ha −1 and 212.4 ± 22.2 kg ha −1 on average, reaching > 300 kg ha −1 after 11 and 9 years, respectively, SFwP yields remained significantly lower than SFnP, with an average of 58.0 ± 9.5 kg ha −1 and maximum yield of 122.6 ± 36.5 kg ha −1 . This study demonstrates there may be a trade-off between pruning intensity and yield in AF and SFwP, as observed on young CNB trees’ yield developments and yield increases during two years without pruning in mature trees. Based on preliminary results and CNB-specific phenology, we suggest a moderate pruning intervention early in July (allowing recovery time before start of flowering season in August), along with the need for validation of our findings and further investigation into management practices tailored to CNB.
Farm Resilience in Organic and Nonorganic Cocoa Farming Systems in Alto Beni, Bolivia
(Taylor & Francis, 2015) Johanna Jacobi; Monika Schneider; Maria Pillco Mariscal; Stéphanie Huber; Simon Weidmann; Patrick Bottazzi; Stephan Rist
Cocoa production in Alto Beni, Bolivia, is a major source of income and is severely affected by climate change impacts and other stress factors. Resilient farming systems are, thus, important for local families. This study compares indicators for social–ecological resilience in 30 organic and 22 nonorganic cocoa farms of Alto Beni. Organic farms had a higher tree and crop diversity, higher yields and incomes, more social connectedness, and participated in more courses on cocoa cultivation. Resilience was enhanced by local farmers’ organizations, providing organic certification and supporting diversified agroforestry with seedlings and extension, going beyond basic organic certification requirements.
La contribución de la producción del cacao orgánico a la resiliencia socio-ecológica en el contexto del cambio climático en el Alto Beni – La Paz
(ETH Zurich, 2014) Johanna Jacobi; Monika Schneider; María Isabel Pillco Mariscal; Stéphanie Huber; Simon Weidmann; Stephan Rist
El cultivo del cacao en pequeña escala, sustento básico de muchas familias del Alto Beni, es afectado por los impactos del cambio climático. Para el desarrollo sostenible, es necesario que las fincas adquieran resiliencia: la capacidad de un sistema para reducir su sensibilidad hacia factores de estrés y perturbaciones, manteniendo su productividad, capacidad auto-organizativa, de aprendizaje y adaptación al cambio. Investigamos las diferencias en la resiliencia entre las fincas orgánicas y no orgánicas de cacao, y los rasgos significativos que inciden en la resiliencia socio-ecológica de los sistemas agrícolas del cacao. Definimos indicadores de resiliencia con expertos locales y productores durante un taller y con grupos focales. Los indicadores de la capacidad de amortiguación fueron: materia orgánica de los suelos, densidad aparente del suelo, e infestación con Moniliophthora perniciosa, diversidad arbórea, diversidad de cultivos, hormigas y fuentes de ingresos de las familias productoras. Los indicadores de auto-organización fueron: afiliación a organizaciones productoras, nivel de subsistencia, rendimientos de cacao e ingreso familiar anual. La capacidad de adaptación se evaluó indagando la cantidad de capacitaciones en que participaron las familias y la cantidad de fuentes de información que poseían. Entrevistamos 52 hogares: 30 orgánicos, 22 no orgánicos. Las fincas orgánicas en el área eran más diversificadas y rendían más. El ingreso familiar anual de las fincas orgánicas era sustancialmente mayor al de las no orgánicas. Probablemente el mayor rendimiento se debió principalmente a que los productores orgánicos participaron en más capacitaciones debido a su pertenencia a las organizaciones locales. Concluimos que las organizaciones locales de agricultura orgánica contribuyeron a crear resiliencia proporcionando servicios de extensión mediante el establecimiento de parcelas, creación de capacidades y seguros sociales.
Locally-selected cacao clones for improved yield: a case study in different production systems in a long-term trial
(Frontiers Media, 2023) Laura Armengot; Marco Picucci; Joachim Milz; Jon Kehlet Hansen; Monika Schneider
Ageing plantations, poor genetic material, soil degradation, pests and diseases are, among other factors, limiting cacao production. To meet the increasing demand for cacao in the absence of productivity gains, forests are cleared and the use of external inputs is generalised, with severe negative impacts on biodiversity and GHG emissions. The use of improved plant genetic material should support a sustainable increase of production. In this study, we evaluate and compare the yield performance of four locally-selected clones with those of four widely-used international clones in South America and four full-sib families (crosses of the same international clones). The research was conducted in a long-term trial in Bolivia with different production systems, including monocultures and agroforestry systems under organic and conventional farming and a successional agroforestry system without external inputs. Their cacao yields and the factors determining productivity (pod index, flowering intensity, pod load, pod losses, aboveground biomass, harvesting period) were assessed during 5 years. The cacao trees grown in the two monocultures had higher yields than those in the agroforestry systems. This was the result of higher aboveground biomass, flowering intensity and pod load, and similar pod losses due to cherelle wilt and fungal diseases in the former when compared with the latter. No differences between conventional and organic management were observed. We did not identify any genotypes performing better in a specific production system. On average, the local clones had twofold and five times higher yields than the international ones and the full-sib families, respectively. This was related to their higher total pod load, bigger pods and higher yield efficiency, i.e., higher yield per unit of tree biomass. However, the local clones had less flowering intensity, more cherelle wilt and similar losses due to fungal diseases to those of the international clones. This study clearly shows the need to invest in selection and breeding programmes using locally-selected genetic material to increase cacao production and support renovation/rehabilitation plans. Breeding genetic material that is adapted to low light intensities is crucial to close the yield gap between monocultures and agroforestry systems, and to further promote the adoption of the latter.
Microbial biomass and cellulase activity in soils under five different cocoa production systems in Alto Beni, Bolivia
(Springer Science+Business Media, 2015) Adalid Alfaro-Flores; Isabel Morales-Belpaire; Monika Schneider
Selección de diferentes sistemas de producción de cacao (Theobroma cacao, Malvaceae) por aves en Alto Beni, Bolivia - una prueba de cafetería en el campo
(2017) Kazuya Naoki; M. Isabel Gómez; Monika Schneider
El cacao (Theobroma cacao, Malvaceae) es una especie nativa de Sudamerica, y se considera que su cultivo cumple un rol importante para la conservacion de biodiversidad. Se estudio la seleccion de aves entre cinco sistemas de produccion de cacao y barbecho, a traves de una prueba de cafeteria en Alto Beni, Bolivia. Las aves fueron cuantificadas por medio del conteo de punto modificado durante la epoca seca. Se registraron 239 visitas de 43 especies de aves pertenecientes a 18 familias. El numero de especies y la frecuencia de visitas de las aves estuvieron relacionadas positivamente con la complejidad de la estructura vegetal y la diversidad de arboles, disminuyendo desde el barbecho, el sistema agroforestal sucesional (SAFS), los sistemas agroforestales, hasta los monocultivos (β1 = - 0.149 ± 0.046 para el numero de especies, β1 = - 0.167 ± 0.078 para la frecuencia de visitas). En los monocultivos se registro la mitad del numero de especies observadas en las parcelas de barbecho. En los cultivos convencionales la frecuencia de visitas de aves disminuyo hasta un 37-46% de la frecuencia observada en las parcelas de barbecho. Se observo una mayor similitud en la composicion de aves entre el SAFS y el barbecho, sugiriendo que el SAFS, al tener una estructura vegetal diversa, alberga recursos mas similares al barbecho. Es importante incentivar los sistemas agroforestales complejos de cacao para la conservacion de las aves en los paisajes agricolas.
Successional agroforestry promotes biomass carbon storage in cocoa production systems: results from a long-term system comparison experiment on organic and conventional systems
(Elsevier BV, 2025) Hans‐Martin Krause; Stéphane Saj; Johanna Rüegg; Ulf Schneidewind; Sina Lory; Marc Cotter; Wiebke Niether; Monika Schneider; Johannes Milz; Georg Cadisch
Agroforestry systems are perceived as an effective approach to store carbon in agroecosystems by building tree biomass and raising soil organic carbon (SOC) stocks. This is especially evident in the tropics, where the cultivation of cash crops such as cacao in agroforestry systems is increasingly used. Among agroforestry systems, organic management, which avoids synthetic inputs for crop protection and fertilization, and the concept of successional agroforestry (SA), which aims to increase carbon storage by using high initial tree densities and intensive pruning without external inputs, have gained interest as alternatives to monocultures with less environmental impact. To assess the temporal development of carbon storage of differently managed agroforestry systems, we revisited a 14-year field experiment located in the Alto Beni Region of Bolivia to quantify biomass and SOC stocks in five distinct cocoa production systems. The field experiment includes SA as well as organic and conventional monocultures (OM and CM) and agroforestry systems (OA and CA). We found that all agroforestry systems increased carbon stocks in the biomass and the soil, especially in the particulate organic matter fraction. No significant effect of organic management practices was observed. After 14 years, the highest biomass carbon was observed in the SA system and topsoil SOC stocks increased significantly in SA and CA. Our findings emphasize the potential to enhance carbon accumulation in agroforestry systems with high initial tree density and rigorous pruning, even without additional fertilizer or synthetic plant protection inputs. • Agroforestry enhances soil and biomass carbon stocks compared to cacao monocultures • No effect of organic management on soil and biomass carbon within agroforestry systems. • Greatest gains of biomass carbon in successional agroforestry systems