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81.
The Fitzroy estuary (Queensland, Australia) receives large, but highly episodic, river flows from a catchment (144,000 km(2)) which has undergone major land clearing. Large quantities of suspended sediments, and particulate and dissolved organic carbon are delivered. At peak flows, delta(13)C (-21.7+/-0.8 per thousand) and C/N (14.8+/-1.3) of the suspended solids indicate that the particulate organic material entering the estuary is principally soil organic carbon. At the lower beginning flows the particulate organic matter comes from in-stream producers (delta(13)C=-26 per thousand). The DOC load is about 10 times the POC load. Using the inverse method, budgets for POC and DOC were constructed for high and low flows. Under high flows, only a small portion of the POC and DOC load is lost in the estuary. Under dry season (low flow) conditions the estuary is a sink for DOC, but remains a source of POC to the coastal waters. 相似文献
82.
Elsbeth Robson 《Area》2000,32(1):59-69
Summary Women and young people are disproportionately burdened by the restructuring of healthcare services. Home-based healthcare provision by children in Zimbabwe is investigated through qualitative interviews with young carers and key informants. The study suggests that young people (especially girls) become carers according to varied personal and household factors in the context of the AIDS pandemic, macro-economic decline and ESAP-weakened formal health services. 相似文献
83.
Site procedures, instrumentation, analytical methods and accuracies achieved are described for the measurement of the deformation of a military steel bridge under load in a test gantry. Some remarks concerning the advantages and disadvantages of photogrammetry as a method of industrial measurement are made. 相似文献