Producing enough healthy food for a globally growing urban population within planetary boundaries requires more resource-efficient and localized food production systems. Controlled-environmental food ...production systems (CEFPS) are a widely discussed new approach for sustainable food production in urban contexts. However, little research has addressed innovation processes of CEFPS in urban or rural areas. This paper aims to address this research gap by adapting an innovation system perspective, developing a conceptual framework for 'urban food production innovation systems' (UFoPrInS) and applying it to a paradigmatic case study in Berlin. Based on a content analysis of the relevant literature and 23 semi-structured expert interviews, we analyse (a) the main characteristics and (b) the key elements of the UFoPrInS and their relationships during different stages of the innovation process. The case results show that UFoPrInS faces various challenges related to possible structural failures that can occur in infrastructure, interactions, capabilities of actors and institutions. The current institutional framework at EU and national level was seen as the major barrier to innovations. To support new food production innovations, a comprehensive regulatory framework for CEFPS is needed that considers in an integrated approach the specifics of (1) the highly-intensive production processes, (2) the diverse types of products and (3) the urban location.
Reduction of Substrates by Nitrogenases Seefeldt, Lance C; Yang, Zhi-Yong; Lukoyanov, Dmitriy A ...
Chemical reviews,
06/2020, Letnik:
120, Številka:
12
Journal Article
Recenzirano
Odprti dostop
Nitrogenase is the enzyme that catalyzes biological N2 reduction to NH3. This enzyme achieves an impressive rate enhancement over the uncatalyzed reaction. Given the high demand for N2 fixation to ...support food and chemical production and the heavy reliance of the industrial Haber–Bosch nitrogen fixation reaction on fossil fuels, there is a strong need to elucidate how nitrogenase achieves this difficult reaction under benign conditions as a means of informing the design of next generation synthetic catalysts. This Review summarizes recent progress in addressing how nitrogenase catalyzes the reduction of an array of substrates. New insights into the mechanism of N2 and proton reduction are first considered. This is followed by a summary of recent gains in understanding the reduction of a number of other nitrogenous compounds not considered to be physiological substrates. Progress in understanding the reduction of a wide range of C-based substrates, including CO and CO2, is also discussed, and remaining challenges in understanding nitrogenase substrate reduction are considered.
Há duas décadas, estudos arqueobotânicos demonstram a importância das plantas em sambaquis, recentemente apontando para um regime de economia mista, com pesca e coleta associadas à horticultura. No ...entanto, pesca e consumo de proteína animal são considerados centrais nas esferas econômicas e sociais dessas pessoas, enquanto o papel das plantas permanece subestimado. A relevância das plantas é demonstrada por vestígios botânicos que são menos conspícuos do que os faunísticos, mas não menos significativos. Assim, discutimos aqui a sociedade sambaquiana enquanto “sociedade de meio termo”, conceito que engloba uma enorme variedade de modos de vida que não se enquadram na concepção ultrapassada da dicotomia forrageadores versus agricultores e que foram muito mais comuns e duradouros do que se costuma pensar.
Blockchain is an emerging digital technology allowing ubiquitous financial transactions among distributed untrusted parties, without the need of intermediaries such as banks. This article examines ...the impact of blockchain technology in agriculture and food supply chain, presents existing ongoing projects and initiatives, and discusses overall implications, challenges and potential, with a critical view over the maturity of these projects. Our findings indicate that blockchain is a promising technology towards a transparent supply chain of food, with many ongoing initiatives in various food products and food-related issues, but many barriers and challenges still exist, which hinder its wider popularity among farmers and systems. These challenges involve technical aspects, education, policies and regulatory frameworks.
•Discussion of the impact of blockchain in agriculture and food supply chains.•Presentation of many ongoing existing projects and initiatives.•The maturity level of these projects is analyzed.•Blockchain is a promising technology towards a transparent supply chain of food.•Existing challenges involve accessibility, governance, technical aspects, policies and regulatory frameworks.
Agricultural origins on the Anatolian plateau Baird, Douglas; Fairbairn, Andrew; Jenkins, Emma ...
Proceedings of the National Academy of Sciences - PNAS,
04/2018, Letnik:
115, Številka:
14
Journal Article
Recenzirano
Odprti dostop
This paper explores the explanations for, and consequences of, the early appearance of food production outside the Fertile Crescent of Southwest Asia, where it originated in the 10th/9th millennia ...cal BC. We present evidence that cultivation appeared in Central Anatolia through adoption by indigenous foragers in the mid ninth millennium cal BC, but also demonstrate that uptake was not uniform, and that some communities chose to actively disregard cultivation. Adoption of cultivation was accompanied by experimentation with sheep/goat herding in a system of low-level food production that was integrated into foraging practices rather than used to replace them. Furthermore, rather than being a short-lived transitional state, low-level food production formed part of a subsistence strategy that lasted for several centuries, although its adoption had significant long-term social consequences for the adopting community at Boncuklu. Material continuities suggest that Boncuklu’s community was ancestral to that seen at the much larger settlement of Çatalhöyük East from 7100 cal BC, by which time a modest involvement with food production had been transformed into a major commitment to mixed farming, allowing the sustenance of a very large sedentary community. This evidence from Central Anatolia illustrates that polarized positions explaining the early spread of farming, opposing indigenous adoption to farmer colonization, are unsuited to understanding local sequences of subsistence and related social change. We go beyond identifying the mechanisms for the spread of farming by investigating the shorter- and longer-term implications of rejecting or adopting farming practices.
Abstract
Soil phosphorus (P) loss from agricultural systems will limit food and feed production in the future. Here, we combine spatially distributed global soil erosion estimates (only considering ...sheet and rill erosion by water) with spatially distributed global P content for cropland soils to assess global soil P loss. The world’s soils are currently being depleted in P in spite of high chemical fertilizer input. Africa (not being able to afford the high costs of chemical fertilizer) as well as South America (due to non-efficient organic P management) and Eastern Europe (for a combination of the two previous reasons) have the highest P depletion rates. In a future world, with an assumed absolute shortage of mineral P fertilizer, agricultural soils worldwide will be depleted by between 4–19 kg ha
−1
yr
−1
, with average losses of P due to erosion by water contributing over 50% of total P losses.
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