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Design for Sustainability ; Methodology and Organisation of Design

Based on the case of HidroAysén, in this paper we discuss the different modes of existence of a hydroelectric project. Inspired by an ontological sensibility and the idea of worlding, we sustain that hydroelectric energy is embedded in, and is the source of, multiple worlds where different ontologies of water and energy meet, not always peacefully. Drawing on in-depth interviews and documentary sources, we identify three worlds or realities–yet not entirely autonomous–in which the HidroAysén project exists: the National Hydropower World, the Market Hydropower World, and the Sustainable Hydropower World. We argue that these three realities, through different ecologies, knowledge, and narratives, execute different parameters of reality and objectivity. Our final argument is that an ontological approach to analyze hydropower development and the conflicts that it has spurred can stimulate new ways of thinking about taken-for-granted assumptions, categories, and practices regarding the way hydropower is or might be produced.

Resumen: El artículo analiza cómo el desarrollo hidroeléctrico en la cuenca del Rímac, en la región de Lima, Perú, ha reconfigurado las relaciones hidrosociales entre los distintos usuarios del agua desde el siglo XIX. Muestra específicamente de qué modo el desarrollo hidroeléctrico estuvo basado en discursos sobre la modernidad, la civilización y la necesidad de domesticar la naturaleza y las personas a través de la ingeniería; y en segundo lugar, cómo aquello condujo a una alianza entre la compañía hidroeléctrica y la de agua potable de la ciudad de Lima. Sin embargo, dicho desarrollo no ha llevado a las comunidades rurales a verse privadas del agua, sino a nuevas dependencias y relaciones de poder que, incluso, podrían proveer de más agua a los campesinos. Recientemente, tanto el resurgimiento de nuevos proyectos hidroeléctricos en la cuenca como incertidumbres sobre los efectos del cambio climáctico han generado preocupación de las comunidades con respecto a la distribución de los beneficios y su posición dentro de las redes ecológicas y sociopolíticas de la cuenca.

In this study, quantitative and qualitative microbiological parameters were evaluated to detect differences related to soil and crop management. The study was carried out in a field experiment installed 14 years ago on a Rhodic Eutrudox, in Londrina, PR, Brazil. Treatments were a combination of a crop sequence (S) (soybean/wheat) and a crop rotation (R) (lupin/maize/black oat/soybean/wheat/soybean/wheat/soybean), either under conventional tillage (CT) or no-tillage (NT). Evaluations were performed when all systems were under the soybean cropping season, at full flowering. Amounts of microbial biomass carbon and nitrogen (MB-C and MB-N, respectively) were 114 and 157% higher in NT than in CT. Furthermore, the metabolic quotient (qCO(2)) was lower under NT, indicating higher metabolic efficiency of the soil microbes. These parameters were not affected by the crop sequence/rotation. Genetic diversity of the total soil bacterial community was higher under NT and lower in the CT system with crop sequence. Regarding the biological N-2 fixation, it was found that plant biomass, total N and fraction of N-ureides in shoots, as well as nodule efficiency, were higher under NT. Genetic diversity of rhizobia was affected mainly by crop management and was higher under crop rotation, probably due to the greater number of plant species. However, crop rotation decreased the efficiency of the biological N-2 fixation process, which may be related to more abundant N in the soil or to a lower selection pressure for efficient rhizobia. For soil microbes with specific functions, e.g., rhizobia, genetic diversity may therefore differ from functionality.

Jatropha seed is a biomass suitable for bioenergy production that can be produced by smallholders, even on marginal lands. However, the current oilseed production is too low to meet the needs of the planned renewable electricity system in the Galapagos Islands. Pruning and fertilization are management options that can be used to increase the dry seed yields. The effects of both treatments were tested in a split-plot design with jatropha trees, which were monitored during a three-year production period. The average seed production was 643±58 kg ha-1 year-1 in the unpruned trees and 696±50 kg ha-1 year-1 in the pruned trees. Although this difference is small, it is expected to increase over time. The pruned trees developed more slowly than the unpruned trees but showed higher (and still increasing) yields at the end of the three-year test period, while the unpruned trees appeared to have reached their maximum production by the second year of the trial. The low fertilizer doses approved by the smallholders did not have a significant impact on the dry seed yield, and the management options that show benefits in the long term are generally not accepted or adopted by them. Cost-effective nutrient enhancement should be investigated, such as inoculation with arbuscular mycorrhizal fungi.

Dit nieuwe boek van ruraal socioloog Jan Douwe van der Ploeg is een pleidooi voor een nieuwe boerenlandbouw als een agrarisch systeem dat het best en meest duurzaam de zorg op zich kan nemen voor de vele cultuurlandschappen die de wereld rijk is. De oude landbouw wordt namelijk steeds meer gedomineerd door wereldwijde conglomeraten als het Italiaanse Parmalat. Terwijl familiebedrijven ook in tijden van mindere economische voorspoed blijven boeren op de plek waar ze zijn, en dus ook het landschap onderhouden waarop ze boeren, schakelt de internationale agroindustrie net zo gemakkelijk van een akker in Afrika naar die in Amerika of Europa, naar gelang de grondkosten, de productie per hectare en de arbeidskosten.