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1.
In recent years, bio-energy with carbon capture and storage (BECCS) has been awarded a key role in climate mitigation scenarios explored by integrated assessment models and referenced in reports by the Intergovernmental Panel on Climate Change. Because a majority of scenarios limiting global warming to 2 °C or 1,5 °C include vast deployment of BECCS, a critical discussion has emerged among experts about the moral implications of thus introducing an unproven technology into the policy realm.In this paper, we analyse this discussion as it has played out between 2013 and 2019, with a focus on how expert narratives are constructed in the mass media about the possibilities for decarbonisation within the current political-economic order. We find there are almost no narratives that support massive deployment of BECCS, and that all narratives presuppose limits to decarbonisation imposed by the current political-economic system. The perception of such limits lead some to argue, through deterministic and apolitical narratives, for the necessity of negative emissions technologies, while others argue instead that “degrowth” is the only solution. Thus, there is a distinct lack of positive narratives about how capitalism can bring about decarbonisation.  相似文献   
2.
Fermentation is a common method of processing and preserving breadfruit throughout the Pacific Islands. While these pits are often reported in the archaeological record, they can pose some interpretive challenges. This paper presents an analysis of probable archaeological breadfruit (Artocarpus altilis (Parkinson) Fosberg) fermentation pits on Temwen Island, Pohnpei, Micronesia. Using the existing ethnographic record as a guide, I present archaeological and paleoethnobotanical criteria for identifying fermentation features. Architectural and stratigraphic analyses from four excavated pits match ethnographic expectations. Phytolith analysis shows some concurrence in terms of taxonomic data, but is more useful for indicating disturbance specific to building activities. Based on the distribution and size of pits present in the survey area, I suggest that breadfruit fermentation took place as primarily a household level (rather than community level) activity during the late prehistoric and early historic period in Pohnpei.  相似文献   
3.
This article analyses processes of uneven urbanisation by looking at flood infrastructure. Combining the conceptual frameworks of uneven development with the political ecology of urbanisation, we use flood infrastructure as a methodological device to trace the processes through which unevenness occurs within, but also far beyond, the city of Jakarta, Indonesia. We do this to show how the development of flood infrastructure in Jakarta is shaped by the logic of capitalism through mutually implicated tendencies of socionatural differentiation and equalisation. These processes render waters, resources and labour as similar across places and times to produce different spaces for different populations, within and beyond city boundaries. This theorisation reveals how the urban inequalities (re)produced by flood infrastructure are intimately linked to inequalities (re)produced through the urbanisation of the non‐city.  相似文献   
4.
Abstract

The prehistoric development of food storage represents a major evolutionary transition, one potentially more important than the initial domestication of plants. Researchers, however, have yet to really deal with some of the critical practical questions related to the materiality of food storage and decision-making. Drawing upon experimental research this paper seeks to identify and model some of the critical interconnections between anticipated food loss due to spoilage, storage decision-making and the need for people to store food for multiple years. Building on this foundation, and echoing ethnographic, ethnoarchaeological and archaeological research, this study argues that the concept of storage and surplus is underdeveloped and that in many cases the storage practices of prehistoric sedentary people do not reflect a food surplus so much as normal storage. Turning to a case study of changing Near Eastern Neolithic grain storage practices, this research argues that from the Natufian through Neolithic periods people increasingly relied upon cultivated domesticated plants and food storage. This required people to expand their use of pre-existing technology, such as plaster for lining storage features, to store sufficient amounts of food to overcome seasonal shortages, potential crop failures and minimise food spoilage due to a range of biological agents. Tracking shifts through time, the results of this study suggest that it is only with increased scale of food storage in the later stages of the Neolithic that we may see a materialization of a food surplus.  相似文献   
5.
CO2 injected into rock formations for deep geological storage must not leak to surface, since this would be economically and environmentally unfavourable, and could present a human health hazard. In Italy natural CO2 degassing to the surface via seeps is widespread, providing an insight into the various styles of subsurface ‘plumbing’ as well as surface expression of CO2 fluids. Here we investigate surface controls on the distribution of CO2 seep characteristics (type, flux and temperature) using a large geographical and historical data set. When the locations of documented seeps are compared to a synthetic statistically random data set, we find that the nature of the CO2 seeps is most strongly governed by the flow properties of the outcropping rocks, and local topography. Where low‐permeability rocks outcrop, numerous dry seeps occur and have a range of fluxes. Aqueous fluid flow will be limited in these low‐permeability rocks, and so relative permeability effects may enable preferential CO2 flow. CO2 vents typically occur along faults in rocks that are located above the water table or are low permeability. Diffuse seeps develop where CO2 (laterally supplied by these faults) emerges from the vadose zone and where CO2 degassing from groundwater follows a different flow path due to flow differences for water and CO2 gas. Bubbling water seeps (characterized by water bubbling with CO2) arise where CO2 supply enters the phreatic zone or an aquifer. CO2‐rich springs often emerge where valleys erode into CO2 aquifers, and these are typically high flux seeps. Seep type is known to influence human health risk at CO2 seeps in Italy, as well as the topography surrounding the seep which affects the rate of gas dispersion by wind. Identifying the physical controls on potential seep locations and seep type above engineered CO2 storage operations is therefore crucial to targeted site monitoring strategy and risk assessment. The surface geology and topography above a CO2 store must therefore be characterized in order to design the most effective monitoring strategy.  相似文献   
6.
Abstract

A consistent access to food is paramount for humans at individual and group level. Besides providing the basic nutritional needs, access to food defines social structures and has stimulated innovation in food procurement, processing and storage. We focus on the social aspects of food storage, namely the role of cooperation for the emergence and maintenance of common stocks. Cooperative food stocks are examined here as a type of common-pool resource, where appropriators must cooperate to avoid shortage (i.e. the tragedy of commons). ‘Food for all’ is an agent-based model in which agents face the social dilemma of whether or not to store in a cooperative stock, adapting their strategies through a simple reinforcement learning mechanism. The model provides insights on the evolution of cooperation in terms of storage efficiency and considering the presence of social norms that regulate reciprocity. For cooperative food storage to emerge and be maintained, a significant dependency on the stored food and some degree of external pressure are needed. In fact, cooperative food storage emerges as the best performing strategy when facing environmental stress. Likewise, an intermediate control over reciprocity favours cooperation for food storage, suggesting that concepts of closed reciprocity are precursors to cooperative stocks, while excess control over reciprocity is detrimental for such institution.  相似文献   
7.
8.
朱浒 《史学月刊》2007,(2):104-112
光绪十三年(1887年)黄河在郑州决口,是铜瓦厢改道后最大的一次黄河水灾。对于此次水灾期间的赈灾事务,学界以往甚少注意。实际上,此时以江南绅商为主体的民间力量自发组织动员的义赈活动,不仅承担了此次赈务中的很大一部分工作,而且是整个晚清义赈机制发展到一个新阶段的标志,其实践逻辑甚至还可以帮助我们推进此前关于地方史研究取向中国家与社会的关系的反思。  相似文献   
9.
While recent research on temporary clusters and temporary markets has emphasized the knowledge generation processes associated with trade fairs, little is known about the knowledge exchanges that are embedded in market relations at these events. This paper uses the case of the Canton Fair in Guangzhou, the largest trade fair in China, to illustrate that such events do not operate as a single market, but that they generate multiple dynamic market configurations, which entail different flows of knowledge, goods and people. In a typical case study, four types of market configurations are identified that simultaneously develop at this event. The findings contribute to a more comprehensive understanding of the dynamics of market relations, knowledge and transactions in temporary spatial settings.  相似文献   
10.
Vern Baxter 《对极》2014,46(4):1014-1031
This paper presents results from a study of environmental harm created in the collision of real estate speculation and the political process that governed extension of the urban frontier of New Orleans into its eastern wetlands. Near term concerns of rent‐seeking real estate capital and the contested politics of urban infrastructure expansion challenged a fragmented state charged with regulatory oversight and protection of investments in land and citizens. The paper engages theoretically the relative inattention of urban political ecology theory to rent as a way to theorize how capital flows through land, and argues for increased attention to the problem of land rent and the multiple scales of political engagement that manage ecological crisis immanent in the metabolism of nature and society under capitalism.  相似文献   
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