Aquaculture uses large volumes of water, which is generally discharged without treatment, possibly causing scarcity and contamination. A sustainable aquaculture option is biofloc technology (BFT), which recycles food residues and toxic organic and inorganic compounds from the system through microorganisms, avoiding excessive use of water and serving as natural food for cultured aquatic organisms. The aim of this study was to identify the main factors that limit a Mexican aquaculture producer from adopting biofloc technology in their aquaculture production units (APUs). Strengths and weaknesses were methodologically analyzed through 248 questionnaires, applied to fish farmers in 16 states of the country with a mixed approach (quantitative and qualitative). Findings reveal that the main obstacles in the use of BFT are due to the following: low academic level, limited administrative capacity, scarce technological equipment in facilities, diversified productive activity, and obsolete regulations. Other factors that promote the adoption of BTFs for aquaculturists are production experience, favorable weather conditions, and abundant availability of water and energy. In conclusion, the use of BTF is a sustainable option for APUs despite the limiting factors identified in this research which slow down the growth of the sector. It is advisable to study Mexican producers with BFT, in order to spread their benefits to other APUs, and further evaluate the productivity of the aquaculture sector. This study considers production aspects, and also sustainable use of its resources, specifically, surface, energy, water, and food.

Conventional aquaculture (ACUA-C) in Mexico is an activity that maintains an annual growth rate of 6%. Tilapia (Oreochromis niloticus) aquaculture is the predominant aquaculture in the country with 4623 farms, most of which operate with semi-intensive (SIS) and extensive (ES) production systems, discharging untreated wastewater that negatively impacts the environment. To address this problem, new ecotechnologies such as biofloc (BFT), recirculation systems for aquaculture (RAS), constructed wetlands (CWs) for water treatment, and aquaponics (AS) have emerged to mitigate the environmental impacts of untreated wastewater. The objective of this work is to evaluate the feasibility of tilapia farming with BFT, RAS, CW, and AS ecotechnologies through an economic and financial feasibility analysis, considering their environmental and social implications in a Mexican aquaculture farm located in the state of Veracruz. Open interviews, direct observation, and diagnosis of the semi-intensive tilapia system was carried out between 15 May 2019 and 15 February 2020 in order to calculate, design, and theoretically evaluate the four ecotechnological alternatives (TBF, RAS, CW, and AS). Economic (13), environmental (10), and social (5) variables were applied, making use of the same facilities. The results reveal that the four ecotechnologies implemented in an SIS are economically viable and environmentally acceptable, especially in water management, in addition to being socially feasible. It is concluded that BFT offers an alternative to the producer by having a lower additional cost to improve problems, despite the possible complexity of operation and energy requirements to manage wastewater treatment. The technological transition to BFT is recommended to solve the problem of sustainable water management.

English The abuse of inorganic fertilizers in coffee agroecosystems is a worldwide problem. In central Mexico, organic fertilizers are being introduced as an alternative way to restore soil fertility. The aim of this study was to investigate coffee farmers from central Veracruz’s perceptions of bat guano as organic fertilizer. Surveys were conducted with closed and open questions followed by quantitative and qualitative analysis. Eighty-eight percent of the farmers surveyed negatively perceived bat guano. Factors influencing this perception were bats’ physical appearance, their role as disease transmitters, and the difficulties in procuring guano, including the resources needed to extract it, handle it, and transport it safely to their workplaces.Spanish El abuso de fertilizantes inorgánicos en los agroecosistemas del café es un problema mundial. En el centro de México se comienzan a emplear fertilizantes orgánicos como alternativa para restaurar los suelos. El objetivo de este estudio fue investigar la percepción de los caficultores sobre el empleo del guano de murciélago como fertilizante. Se realizaron encuestas con preguntas abiertas y cerradas que se analizaron cuantitativa y cualtitativamente. El ochenta y ocho por ciento de los cafeticultores encuestados percibieron negativamente al guano de murciélago. Los factores que influyeron en esta percepción fueron: la apariencia física de los murciélagos, su rol como transmisores de enfermedades y las dificultades para adquirir el guano, incluyendo los recursos necesarios para extraerlo, manipularlo y transportarlo de manera segura a sus fincas cafetaleras.French L’abus d’engrais inorganiques dans les agroécosystèmes de café est un problème mondial. Dans le centre du Mexique, les engrais biologiques commencent à être utilisés pour restaurer les sols. Notre recherche se proposait d’étudier la perception de l’utilisation du guano de chauve-souris comme engrais organique par les caféiculteurs. Des enquêtes semi-structurées (comprenant des questions ouvertes et fermées) ont été menées à partir de méthodes quantitatives et qualitatives. Quatrevingt-huit pour cent des agriculteurs interrogés perçoivent ce guano de manière négative. Parmi les facteurs qui influencent cette perception se trouvent l’apparence physique des chauves-souris, la transmission de maladies et les difficultés pour acquérir le guano, y compris les ressources nécessaires pour l’extraire, le manipuler et le transporter en toute sécurité vers leurs exploitations.

English This article assesses the implementation and performance of Local Agenda 21 (LA21) in Mexico over a decade (2004–2013). Official records of municipal evaluations from all 31 Mexican states were analyzed, comprising 39 indicators of four dimensions of sustainable development: institutional, economic, social and environmental. A positive evolution of the implementation of LA21 was observed, with the economic and social dimensions presenting the best and worst performances, respectively. In general, the local governments of northern Mexico performed better than their southern counterparts. The voluntary nature of LA21 implementation is highlighted, yet necessitating a strengthening of municipal capacities in long-term planning, inter-administration continuity, efficacy evaluation, and integration of all sectors into a more coherent municipal agenda.Spanish Este estudio analiza la implementación y desempeño de la Agenda Local 21 (AL21) en México en un periodo de una década (2004– 2013). Se analizaron registros oficiales de evaluaciones municipales de los 31 estados de la república, que comprenden 39 indicadores de cuatro dimensiones del desarrollo sustentable: institucional, económico, social y ambiental. Se observó una evolución positiva en la implementación de la AL21, con las dimensiones económica y social mostrando el mejor y peor desempeños, respectivamente. En general, los gobiernos locales del norte de México tuvieron mejores desempeños que sus contrapartes del sur. Se destaca la naturaleza voluntaria de la implementación de la AL21, que todavía necesita un fortalecimiento de las capacidades municipales en la planificación de largo plazo, en la continuidad inter-administrativa, la evaluación de eficacia y la integración de todos los sectores en una agenda municipal más coherente.French Cette étude analyse la mise en oeuvre et les performances de l’Agenda 21 local (AL21) au Mexique sur une période de dix ans (2004- 2013). Les archives officielles des évaluations municipales des trente-et-un états de la République ont été analysées. Elles comprennent trente-neuf indicateurs de quatre dimensions du développement durable: institutionnel, économique, social et environnemental. Une évolution positive a été observée dans la mise en oeuvre du LA21, les dimensions économique et sociale affichant respectivement les meilleures et les plus basses performances. En général, les administrations locales du nord du Mexique ont obtenu de meilleurs résultats que leurs homologues du sud. On souligne la nature volontaire de la mise en oeuvre de la LA21, qui nécessite toutefois encore un renforcement des capacités municipales dans la planification à long terme, dans la continuité inter-administrative, l’évaluation de l’efficacité et l’intégration de tous les secteurs dans un agenda municipal plus cohérent.