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141.
The colonial era witnessed a fevered quest for exotic medicinal plants by European physicians and scientists. This essay explores the geographical principles that oriented the search towards the lands and peoples of the humid tropics. Believing that God had planted botanical cures for diseases in their places of origin, medicinal plant collectors concentrated their efforts in the pestilential equatorial latitudes. Although many subscribed to the ancient Doctrine of Signatures, colonial bioprospectors discovered early that indigenous and diasporic peoples represented storehouses of plant knowledge. Assuming that native knowhow constituted more instinct than intelligence, Europeans employed coercion, bribes, torture, and promises of freedom to extract their ethnomedical secrets. In the case of especially lucrative healing plants, imperial and colonial entities conspired to pilfer and naturalize endemic species in their distant colonies. In response to this legacy of inappropriate exploitation of native peoples and tropical plants during the colonial era, most present day bioprospectors follow established codes of ethnobotanical ethics.  相似文献   
142.
Understanding the magnitude of and uncertainty around soil carbon flux (SCF) is important in light of California’s efforts to increase SCF (from the atmosphere to soils) for climate change mitigation. SCF depends, to a great extent, on how soils are managed. Here, we summarize the results of an elicitation of soil science and carbon cycle experts aiming to characterize understanding of current SCF in California’s cropland and rangeland, and how it may respond to alternative management practices over time. We considered four cropland management practices—biochar, compost, cover crops, and no-till—and two rangeland management practices, compost and high-impact grazing. Results across all management practices reveal underlying uncertainties as well as very modest opportunities for soil carbon management to contribute meaningfully to California’s climate mitigation. Under median scenarios, experts expect all the surveyed management practices to reverse SCF from negative to positive, with direct carbon additions via biochar and compost offering the best potential for boosting the soil carbon pool.  相似文献   
143.
This paper distinguishes between bridging and bonding social capital to assess their roles for individual farmers’ adaptation strategies taken through technology adoption. Based on primary data collected in Langcang River (LCR) basin area in southwestern China, the paper finds: (1) adaptation measures have been widely taken by surveyed households, but non-infrastructure-based measures are more prevalent than infrastructure-based measures and (2) surveyed households have strong social capital while having weak bridging social capital. Their bonding social capital has significantly positive relationship with their adaptation decisions, but bridging social capital does not have such statistically significant relationship. It recommends that the governments contemplate carefully how to help the poor to get a good combination of bonding and bridging social capital when designing policies to help the rural poor to improve their long-term adaptive capacity and achieve sustainable rural development.  相似文献   
144.
Boundary-Layer Meteorology - Two stratus-lowering marine fog events observed on 28 September and 4 October 2018 during the Coastal Fog (C-Fog) field campaign that took place offshore of eastern...  相似文献   
145.
The Sivas Basin, located in the Central Anatolian Plateau of Turkey, is a foreland basin that records a complex interaction between sedimentation, salt tectonics and regional shortening during the Oligo‐Miocene leading to the formation of numerous mini‐basins. The Oligocene sedimentary infill of the mini‐basins consists of a thick continental succession, the Karayün Formation, comprising a vertical succession of three main sub‐environments: (i) playa‐lake, (ii) fluvial braided, and (iii) saline lacustrine. These sub‐environments are seen as forming a large Distributive Fluvial System (DFS) modified through time as a function of sediment supply and accommodation related to regional changes in climate and tectonic regime. Within neighbouring mini‐basins and despite a similar vertical stratigraphic succession, subtle variations in facies assemblages and thickness are observed in stratigraphic units of equivalent age, thus demonstrating the local control exerted by halokinesis. Stratigraphic and stratal patterns reveal in great detail the complex interaction between salt tectonics and sedimentation including different types of halokinetic structures such as hooks, wedges and halokinetic folds. The regional variations of accommodation/sediment supply led to coeval changes in the architectural patterns recorded in the mini‐basins. The type of accommodation regime produces several changes in the sedimentary record: (i) a regime dominated by regional accommodation limits the impact of halokinesis, which is recorded as very small variations in stratigraphic thickness and facies distribution within and between mini‐basins; (ii) a regime dominated by localized salt‐induced accommodation linked to the subsidence of each individual mini‐basin enhances the facies heterogeneity within the DFS, causing sharp changes in stratigraphic thickness and facies assemblages within and between mini‐basins.  相似文献   
146.
ABSTRACT

Circular migration was one of several enduring themes in Graeme Hugo’s highly productive research career. Although his specialist field was Asian population movement, during the 2000s he became increasingly interested in labour migration in the Pacific Islands. This paper reviews the development of two managed circular migration schemes targeting Pacific labour that emerged following the UN High-level Dialogue on International Migration and Development in 2006. New Zealand’s Recognised Seasonal Employer (RSE) scheme and Australia’s Seasonal Worker Program (SWP) have attracted international attention as the kind of ‘best practice’ temporary labour migration schemes that Hugo had in mind when he emphasised the positive contributions that circular forms of mobility could make to development in both source and destination countries. The two schemes have transformed mobility between the participating countries and have played a major role in the negotiations over a free-trade agreement between Pacific Forum countries, including Australia and New Zealand. Although the schemes have been in operation for almost 10 years, this paper argues that they are not becoming ‘business as usual’; they embody complex systems of relationships between multiple stakeholders that require ongoing management to ensure that they do not become traps for low-skilled, low-paid ‘permanent’ temporary workers.  相似文献   
147.
This article examines the dynamics and politics that led to the adoption in August 1995 of an ambitious and comprehensive legal instrument that aims to regulate the management of straddling and highly migratory fish stocks. In retrospect, such an achievement may appear surprising, but can be partly explained by a number of particularities that had not occurred in past similar international negotiations. Among such key factors were the actors of these negotiations, distant water fishing States and coastal States on the one hand, and other non-State actors on the other hand. Non-governmental organizations in particular played an innovative and important role, as did such inter-governmental organizations as the UN's Food and Agriculture Organization (FAO). At the same time, the proceedings of this Conference owe to two series of dynamics, one global in nature, which ruled the dealings of the actors, and particularly the bargaining between distant water fishing States and coastal nations, the other, a series of shifts that motivated individual States or groups of States to evolve in their positions throughout the more than two years of negotiations. The Conference also needs to be seen within the wider framework of the ‘mosaic’ of international instruments that were being negotiated at the time, in particular the FAO Code of Conduct for Responsible Fisheries. Furthermore, both the Conference and the Agreement are but the first steps in a long process where the commitment of the participating nations will be tested at the implementation stage.  相似文献   
148.
Astronomical high tides and meteorological storm surges present a combined flood hazard to communities and infrastructure. There is a need to incorporate the impact of tide-surge interaction and the spatial and temporal variability of the combined flood hazard in flood risk assessments, especially in hyper-tidal estuaries where the consequences of tide and storm surge concurrence can be catastrophic. Delft3D-FLOW is used to assess up-estuary variability in extreme water levels for a range of historical events of different severity within the Severn Estuary, southwest England as an example. The influence of the following on flood hazard is investigated: (i) event severity, (ii) timing of the peak of a storm surge relative to tidal high water and (iii) the temporal distribution of the storm surge component (here in termed the surge skewness). Results show when modelling a local area event severity is most important control on flood hazard. Tide-surge concurrence increases flood hazard throughout the estuary. Positive surge skewness can result in a greater variability of extreme water levels and residual surge component, the effects of which are magnified up-estuary by estuarine geometry to exacerbate flood hazard. The concepts and methodology shown here can be applied to other estuaries worldwide.  相似文献   
149.
Charnwood Forest (UK) hosts some of the oldest and best-preserved macrofossils known from the Ediacaran. It is the counterpoint to the more widely studied fossil sites of south-eastern Newfoundland (Canada), which include the recently-designated UNESCO World Heritage Site of Mistaken Point. Discoveries made in Charnwood Forest since 2008 have the potential to revolutionise our understanding of the evolution of complex macroscopic life and the subsequent development of ‘modern’ (i.e. Phanerozoic) ecosystems. The sites in Charnwood include the holotypes for several iconic Ediacaran taxa, and potentially both the oldest and youngest representatives of the deep-water Avalon Assemblage. These communities provide a unique opportunity to test models of community ecology, biological endemism and environmental sensitivity and adaptability in the Ediacaran. Here, we review the geology of Charnwood Forest and the palaeobiology of its biotas, and we summarise recent scientific advances in the context of our developing understanding of early macroscopic life. We review the application of Reflectance Transformation Imaging to these ancient communities, and signpost exciting new directions for research in Charnwood Forest, almost 170 years after the fossils were first brought to light.  相似文献   
150.
When the attitudes of local people towards wildlife and conservation are not aligned with those of other stakeholders, significant conflicts can result, potentially undermining conservation efforts. We collected attitudinal data from 171 local people and 59 governmental staff from a Nature Reserve in southwestern China. These attitudinal questions covered key topics of ecosystem services, protected areas and human-wildlife coexistence. Statistically significant (p<0.05) similarities of responses between local people and staff were identified and the nature of any disparity was investigated. The majority of attitudes relating to protected areas (60%) and coexistence (100%) were statistically similar between the two groups, unlike 25% of responses relating to ecosystem services. Few characteristics of staff were statistically associated with their attitudes, whereas responses from local people were frequently associated with sub-village. Such attitudinal studies inform recommendations that consider the potential for future conflicts that might persist following attitudinal disparity between two key stakeholders.  相似文献   
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