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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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