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291.
Food security for a growing world population is high on the list of grand sustainability challenges, as is reducing the pace of biodiversity loss in landscapes of food production. Here we shed new insights on areas that harbor place specific social memories related to food security and stewardship of biodiversity. We call them bio-cultural refugia. Our goals are to illuminate how bio-cultural refugia store, revive and transmit memory of agricultural biodiversity and ecosystem services, and how such social memories are carried forward between people and across cohorts. We discuss the functions of such refugia for addressing the twin goals of food security and biodiversity conservation in landscapes of food production. The methodological approach is first of its kind in combining the discourses on food security, social memory and biodiversity management. We find that the rich biodiversity of many regionally distinct cultural landscapes has been maintained through a mosaic of management practices that have co-evolved in relation to local environmental fluctuations, and that such practices are carried forward by both biophysical and social features in bio-cultural refugia including; genotypes, artifacts, written accounts, as well as embodied rituals, art, oral traditions and self-organized systems of rules. Combined these structure a diverse portfolio of practices that result in genetic reservoirs—source areas—for the wide array of species, which in interplay produce vital ecosystem services, needed for future food security related to environmental uncertainties, volatile financial markets and large scale conflicts. In Europe, processes related to the large-scale industrialization of agriculture threaten such bio-cultural refugia. The paper highlights that the dual goals to reduce pressures from modern agriculture on biodiversity, while maintaining food security, entails more extensive collaboration with farmers oriented toward ecologically sound practices. 相似文献
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295.
集体建设用地流转是促进土地节约集约利用,统筹城乡发展的有效途径。该文根据河东区集体建设用地的现状,分析了影响集体建设用地流转的主要原因,并针对实际情况提出确权登记、建立城乡统一的交易市场、完善流转程序、规范流转收益等破解集体建设用地流转难题的对策和建议。 相似文献
296.
社会记忆的旅游开发分析——以淮南煤炭记忆为例 总被引:1,自引:0,他引:1
科技的发展和人们思维观念的转变,使得新形式的记忆承载物突破单一教育功能的限制,旅游开始介入社会记忆领域。运用社会记忆理论,使用质性分析软件NVivo8.0,对淮南煤炭记忆进行探析,指出淮南煤炭记忆实质上分为两部分,一是煤炭记忆之苦,二是忆苦思甜。最后,探讨了旅游和淮南煤炭记忆的关系,提出了具体的措施来建构煤炭记忆纪念物,包括加强煤炭记忆的档案建设、建设大型矿山公园、市井生活再塑造、多种业态并存。 相似文献
297.
Identifying Nonstationarity in Turbulence Series 总被引:1,自引:1,他引:0
Edgar L Andreas Cathleen A. Geiger George Treviño Kerry J. Claffey 《Boundary-Layer Meteorology》2008,127(1):37-56
Because of rapid forcing by varying cloud and sky conditions, turbulence time series collected in the atmospheric surface
layer over land may often be nonstationary. The meteorological community, however, has no consensus definition of what nonstationarity
is and, thus, no consensus method for how to identify it. This study, therefore, adopts definitions for first-order and second-order
stationarity taken from the time series analysis literature and implements new analysis techniques and probabilistic tests
to quantify first-order and second-order nonstationarity. First-order nonstationarity manifests as a change in the series
mean; second-order nonstationarity, as a change in the variance. The analysis identifies nonstationarity in surface-level
turbulent temperature and water vapour series collected during two sample days with solar forcing influenced by cirrus and
cirrostratus clouds, but that nonstationarity is not as severe as expected despite the rapid thermal forcing by these clouds.
On the other hand, even with negligible cloud forcing, both sample days exhibited severe nonstationarity at night. 相似文献
298.
Abstract The Nojima Fault in Awaji, Hyogo prefecture, Japan, was ruptured during the 1995 Hyogo-ken Nanbu earthquake ( M JMA = 7.2). Toshima is located close to the fault segment, in which a large dislocation has been observed on the Earth's surface. Ikuha is near the southern end of the buried fault that extends from the surface rupture. Stresses are measured on core samples taken at depths of 310 m, 312 m and 415 m at Toshima and a depth of 351 m at Ikuha. The measured stresses show that both sites are in the field of a strike–slip regime, but compression dominates at Toshima. Defining the relative shear stress as the maximum shear stress divided by the normal stress on the maximum shear plane, the relative shear stress ranges from 0.42 to 0.54 at Toshima and is approximately 0.32 at Ikuha. While the value at Ikuha is moderate, those at Toshima are comparably large to those in areas close to the inferred fault of the 1984 Nagano-ken Seibu earthquake. Value amounts greater than 0.4 suggest that there are areas of large relative shear stress along faults, thus having the potential to generate earthquakes. Provided that the cores are correctly oriented, the largest horizontal stresses at shallow depths are in the direction from N113°E to N139°E at Toshima and N74°E at Ikuha, indicating that the fault does not orient optimally for the stress field at both sites. The slip is known to be predominant in the right-lateral strike–slip component. Although this slip may appear contradictory to the stress field at Toshima, the slip direction is found to be parallel to the measured stresses resolved on the fault plane for the first approximation. The ratio of shear stress to normal stress on the fault plane is roughly estimated to be greater than zero and smaller than 0.3 near Toshima. 相似文献
299.
2004年7~8月,利用诱导的1龄四倍体太平洋牡蛎做亲本,通过解剖取卵、人工受精的方法进行四倍体的自群繁殖。结果表明四倍体太平洋牡蛎自群繁殖的受精率为95.54%,孵化率为37.38%,采用同一雌体四倍体牡蛎与二倍体雄贝杂交产生的三倍体组(TD)的受精率为85.19%,孵化率为99.9%,而以二倍体做母本、四倍体做父本的杂交组(DT)的受精率为98.73%,孵化率为87.63%,二倍体对照组的受精率为96.39%,孵化率为99.9%。四倍体牡蛎经自群繁殖培育出稚贝1130粒。经流式细胞仪分析,四倍体太平洋牡蛎幼虫和稚贝的四倍体率均达到100%。幼虫培育过程中,从孵化出D-形幼虫到出现眼点,幼虫的成活率达11.86%,眼点幼虫的变态率高达16.1%。实验证明四倍体太平洋牡蛎可以进行自群繁殖,比诱导的方法简单高效。 相似文献
300.
Rural tourism in Spain: an analysis of recent evolution 总被引:6,自引:0,他引:6
The aim of this paper is to analyse the evolution of Rural Tourism1 (RT) in Spain within a European context. The first step is to examine the development of different “models” of RT and trace some experiences of the application of European policy. In order to set the scene and understand this evolution, the collective imagery on which RT is based is also analysed. This is followed by a study of the development of tourist products and services in rural Spain since the 1980s, as diversification of the traditional sun/sand/sea (3S) tourist economy is sought. The analysis underlines the importance of the role of women, and the consequences of the activity for the economy of rural areas. The purpose is to identify differences in the pattern of evolution with more northern European countries, understand their causes and formulate recommendations for future development. 相似文献