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Diversification is routinely promoted to improve poor rural peoples’ livelihoods. However, policy recommendations for livelihood diversification based on evidence from crop‐cultivating sedentary rural societies may not work for mobile pastoral communities, where socio‐ecological conditions predetermine livestock herding as the preferred livelihood strategy. Using survey and semi‐structured interview data collected from 159 households in the Altay and Tianshan Mountains of Xinjiang, China, this study applies cluster analysis to identify six distinct groups based on livelihood strategies: pastoralists, agropastoralists, crop farmers, wage labourers, hired herders and mixed smallholders. Although pastoralism is the least diverse of these in terms of sources of income, it is significantly more diverse in ecological dimensions such as spatial movement, land use pattern and livestock portfolio. Patterns of livelihood diversification and their relationship with household incomes indicate that pastoralism, although preferred, is unattainable for 55 per cent of households given their meagre asset endowments and the pressure of government policies toward sedentarization. The results strongly suggest that livelihood diversification does not improve welfare for pastoral households. Future development interventions should promote policies that enable households to regain flexible access to pastures and should aim to correct the imbalance of opportunities that exists in northern Xinjiang.  相似文献   
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ABSTRACT This paper presents an empirical technique for valuing large changes in nonmarketed local attributes (e.g., climate amenities) without data describing prices of locally traded commodities like housing. A model of endogenous sorting is used to identify individuals' indirect utility functions, from which the value of the change in the local attribute is recovered while accounting for equilibrium impacts on markets for labor and locally traded commodities. Annual amenity costs of Brazilian climate change are estimated to be between $1.6 and $8.1 billion for a moderate climate change scenario, depending upon the role of migration costs.  相似文献   
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Abstract

Late Cambrian (Iverian, Jiangshanian) agnostoids and trilobites are described from two localities in the Professor Range area of western Tasmania. The fossils occur within a thick folded flysch succession of siltstone, mudstone, quartzwacke sandstone and siliceous conglomerate that forms the lower part of the Owen Group correlatives in this area. The flysch succession has a conformable and probable gradational contact with the underlying Mt Read Volcanics and is abruptly overlain by the siliceous pebble-cobble conglomerate correlated with the Middle Owen Conglomerate of the West Coast Range. The stratigraphically lower southern locality contains the agnostoids Pseudagnostus sp. and Agnostinae gen. et sp. indet. plus the polymerid trilobites Parabolina sp., Hedinaspis sp. cf. H. regalis and Eugonocare sp. The northern locality contains the agnostoids Rhaptagnostus sp. and Pseudagnostus sp. plus the polymerid trilobites Hedinaspis sp. cf. H. regalis, Ketyna? sp. 1, Ketyna? sp. 2, and Cermatops sp. It is possible that most specimens of the cosmopolitan genus Hedinaspis belong in the type species, H. regalis.

Christopher J. Bentley ], 30 Albert Street, Clare SA 5453; James B. Jago ], University of South Australia, School of Natural and Built Environment, Mawson Lakes, SA 5095; Keith D. Corbett ], 35 Pillinger Drive, Fern Tree Tas 7054, Australia.  相似文献   
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ABSTRACT

By 1860, Hawai‘i’s Indigenous population had declined by 75 per cent when compared to its estimated pre-contact level. Legislators and physicians attributed this crisis to the seasonal migration of Hawaiian prostitutes. After contracting syphilis from sailors in Honolulu, these women returned to their Native villages where they unwittingly spread the disease. Drawing on legislation, health reports, and newspapers, this article underscores the urban-rural nature of Hawai‘i’s syphilis epidemic by analyzing the 1860 Act to Mitigate the Evils and Diseases Arising from Prostitution (ATM). The law compelled prostitutes to enlist on a government registry, undergo medical inspections, and submit to treatment if infected. Arresting depopulation, adherents argued, hinged on the government’s ability to police Indigenous women within a conspicuous urban environment. In designing and enacting the ATM, legislators and physicians characterized Honolulu as a syphilitic breeding ground that catalyzed Indigenous depopulation by sheltering transient carriers of this highly gendered disease.  相似文献   
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ABSTRACT

We report a study in which we systematically reviewed the recent literature dealing with human-environment interaction in prehistory. We first identified the 165 most highly cited papers published between 2005 and 2015. We then identified the major research themes covered in the sample of papers and assessed whether the themes fall into clusters and/or vary greatly in popularity. Subsequently, we identified potentially important lacunae. Our review identified dozens of themes and four major clusters: 1) improving our reconstructions of past environments; 2) the impact of climate change on past human societies; 3) human adaptation to past environmental conditions; and 4) human impacts on past environments. We also identified several gaps that led us to make a number of suggestions for future work. One is to pay more attention to the epistemology of causality. A second is to take into account nonlinearity when considering causal relationships. A third is to study the impact of chronological uncertainty on analyses. Lastly, our review revealed that there are differences between the aspects of human-environment interaction in prehistory that interest scholars and those that interest policy-makers and the general public. This needs to be addressed for obvious reasons.  相似文献   
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