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381.
Spatial and temporal patterns of recruitment of reef corals were assessed for the first time in Mozambique by deploying settlement plates at various spatio-temporal scales between October 2012 and October 2013. The abundance of juvenile corals (5?50?mm in diameter) was assessed along transects. Settlement of acroporids was highly seasonal, with 97% of spat settling between July and October 2013. Pocilloporids settled throughout the year, peaking slightly between October 2012 and January 2013. The annual mean larval settlement of up to 1 135 spat m?2 was comparable to that on other East African reefs, but was dominated by acroporids, which constituted over 80% of all spat, whereas pocilloporids settle in higher densities in Kenya and South Africa. The peak settlement season also differed from other African locations. A greater proportion of variance in settlement rates occurred at the spatial scale of kilometres (between sites) and centimetres (between settlement plates) than at the scale of metres (between subsites), implying that most patchiness occurs at those scales. The peak in acroporid settlement coincided with the period of multispecific spawning, with settlement occurring as early as nine days after a spawning event. As no similar spawning events have been reported for other reefs in the area, our results suggest that these spawning events strongly influence overall annual settlement rates and promote high levels of self-seeding at Vamizi. There was no relationship between settlement of larvae to settlement plates and juvenile density on adjacent reefs, suggesting either variable levels of early post-settlement mortality or high interannual variability in settlement. 相似文献
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通过该项目的实施,旨在消除矿山存在的地质灾害隐患和环境污染,改善其地形地貌景观和生态环境,恢复被破坏的土地资源,改善矿山及周边的人居环境和生产投资环境,从而促进南京市浦口区“以人为本、和谐社会”的建设和经济社会的可持续发展。 相似文献
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将多项式曲线拟合和AR(p)模型应用到地表沉降预测实例中。通过实测沉降数据与预测数据的对比分析,从而对两种模型预测的准确性进行比较,实验表明两种模型在沉降预测中具有很好的适用性。 相似文献
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《The Journal of geography》2012,111(4):161-166
Abstract The term geohistorical archaeology was adopted to describe the combination of the techniques and concepts of historical geography, historical archaeology, and history. It is suggested that the field offers the potential of enhanced research and instruction as it pertains to the early historical settlement of an area. Particular emphasis is placed on the use of site material culture as a key to site locations and the period and nature of their use. The basic techniques involved are reviewed, as is the possibility of incorporating classroom units and field projects on local historical settlement at the secondary level. 相似文献
388.
The finite element interpretation is discussed of two load tests carried out on bentonite slurry piles bored in granular soils. The first case concerns a pile belonging to a 12 pile group. An axisymmetric finite element model that reproduces, with reasonable accuracy, the experimental results is developed. The model is then extended to three-dimensional conditions and applied to the analysis of the entire group. The results suggest some comments on the different assumptions that can be adopted in the calculations and on their effects on the global load–settlement curve of the pile group. The second case concerns a load test in which, in addition to the load–settlement data, also the axial strains along the pile were measured through electrical extensometers. The numerical back analyses highlight an apparent contradiction between the two sets of experimental data. On their bases some conclusions are drawn on the possible causes of the observed inconsistency and on the influence of the construction technology on the interaction between the pile tip and the soil underneath it. 相似文献
389.
塑料排水板在海堤、公路、码头、水闸等软基加固工程中应用较广,塑料排水板处理软地基,是用塑料排水板将地基中的水排除,以增加作用于土颗粒的有效应力来加速地基固结沉降,达到提高强度的目的。在九江市日元贷款城市防洪工程八里湖大堤软基处理中成功应用了塑料排水板施工技术,结合该工程实例。介绍了塑料排水板施工工艺。 相似文献
390.