Development of compost maturity and Actinobacteria populations during full-scale composting of organic household waste

AIMS: This study investigates changes in microbiological and physicochemical parameters during large-scale, thermophilic composting of a single batch of municipal organic waste. The inter-relationships between the microbial biomass and community structure as well as several physicochemical parameters and estimates of maturation were evaluated. METHODS AND RESULTS: Analyses of signature fatty acids with the phospholipid fatty acid and ester-linked methods showed that the total microbial biomass was highest during the early thermophilic phase. The contribution of signature 10Me fatty acids from Actinobacteria indicated a relatively constant proportion around 10% of the microbial community. However, analyses of the Actinobacteria species composition with a PCR-denaturing gradient gel electrophoresis approach targeting 16S rRNA genes demonstrated clear shifts in the community structure. CONCLUSIONS: This study demonstrates that compost quality, particularly maturity, is linked to the composition of the microbial community structure, but further studies in other full-scale systems are needed to validate the generality of these findings. SIGNIFICANCE AND IMPACT OF THE STUDY: The combination of signature lipid and nucleic acid-based analyses greatly expands the specificity and the scope for assessing the microbial community composition in composts. The results presented in this study give new information on how the development of the compost microbial community is connected to curing and maturation in the later stages of composting, and emphasizes the role of Actinobacteria in this respect.</p

Agroecology, Food Sovereignty and the New Green Revolution

Frente a la crisis alimentaria global recurrente, las instituciones del régimen corporativo alimentario proponen una nueva Revolución Verde acompañada por la continuación de las políticas económicas neoliberales. En tanto que, para empezar, éstas son causas de las crisis, este enfoque puede empeorar el problema del hambre, en lugar de resolverlo. Construir un contramovimiento depende en parte de la formación de fuertes alianzas estratégicas entre la agroecología y la soberanía alimentaria. Los agroecólogos se enfrentan a decisiones importantes entre versiones reformistas y radicales de la agroecología. La primera versión intenta cooptar la agroecología a la Revolución Verde; la segunda sitúa la agroecología dentro de un movimiento campesino políticamente transformador que busca la soberanía alimentaria.ABSTRACT: In the face of recurrent global food crises, institutions of the corporate food regime propose a new Green Revolution coupled with a continuation of neoliberal economic policies. Because these are causes of the crises to begin with, this approach can worsen rather than end hunger. Building a countermovement depends in part on forging strong strategic alliances between agroecology and food sovereignty. Agroecologists face important choices between reformist and radical versions of agroecology. The former version attempts to co-opt agroecology into the Green Revolution; the latter centers agroecology within a politically transformative peasant movement for food sovereignt