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H. Md. Azamathulla Yong Chong Cuan Aminuddin Ab. Ghani Chun Kiat Chang 《Arabian Journal of Geosciences》2013,6(9):3469-3480
This study presents gene expression programming (GEP), an extension of genetic programming, as an alternative approach to modeling the suspended sediment load relationship for the three Malaysian rivers. In this study, adaptive neuro-fuzzy inference system (ANFIS), regression model, and GEP approaches were developed to predict suspended load in three Malaysian rivers: Muda River, Langat River, and Kurau River [ANFIS (R 2?=?0.93, root mean square error (RMSE)?=?3.19, and average error (AE)?=?1.12) and regression model (R 2?=?0.63, RMSE?=?13.96, and AE?=?12.69)]. Additionally, the explicit formulations of the developed GEP models are presented (R 2?=?0.88, RMSE?=?5.19, and AE?=?6.5). The performance of the GEP model was found to be acceptable compare to ANFIS and better than the conventional models. 相似文献
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对喇家遗址进行了全面的野外考察,在其北部发现完整连续的全新世黄土-古土壤地层剖面。通过系统采样、粒度和磁化率等多种指标测试,结合OSL技术测年断代,建立了完整的土壤地层序列。深入分析土壤沉积物性质与地表过程,揭示了覆盖齐家文化废墟的沉积物的成因。研究结果表明：喇家遗址土壤沉积物地层层序自地表向下依次为：现代土壤（MS,0~1.50 ka B.P.）→全新世晚期风成黄土（L0,1.50~3.10 ka B.P.）→全新世中期古土壤（S0,3.10~8.50 ka B.P.）→全新世早期过渡性风成黄土（Lt,8.50~11.50 ka B.P.）→晚更新世晚期马兰黄土（L1,>11.50 ka B.P.）。其中全新世中期黑垆土古土壤（S0）被3组红色粘土质泥流（RC3、RC2和RC1）和山洪沙土（FFD）沉积层穿插分隔为4个亚层（S0上、S0中上、S0中下和S0下）。这证明黑垆土发育过程中,在OSL年龄3.96~3.65 ka,对应于14C年龄3.85~3.60 ka B.P.出现一个山洪泥流盛行期,来自于盆地北侧沟谷的大规模暴雨山洪泥流,在大红山前古洪积扇前沿溢出沟槽、扩散覆盖了黄河第二级阶地面的土地。其中与大地震相伴随的第一期暴雨山洪泥流过程,摧毁了喇家遗址齐家文化聚落,造成居室内人群的死亡。 相似文献
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L. Petheram K.K. Zander B.M. Campbell C. High N. Stacey 《Global Environmental Change》2010,20(4):681-692
Despite growing global attention to the development of strategies and policy for climate change adaptation, there has been little allowance for input from Indigenous people. In this study we aimed to improve understanding of factors important in integration of Yolngu perspectives in planning adaptation policy in North East Arnhem Land (Australia). We conducted workshops and in-depth interviews in two ‘communities’ to develop insight into Yolngu peoples’ observations and perspectives on climate change, and their ideas and preferences for adaptation. All participants reported observing changes in their ecological landscape, which they attributed to mining, tourism ‘development’, and climate change. ‘Strange changes’ noticed particularly in the last five years, had caused concern and anxiety among many participants. Despite their concern about ecological changes, participants were primarily worried about other issues affecting their community's general welfare. The results suggest that strategies and policies are needed to strengthen adaptive capacity of communities to mitigate over-arching poverty and well-being issues, as well as respond to changes in climate. Participants believed that major constraints to strengthening adaptive capacity had external origins, at regional, state and federal levels. Examples are poor communication and engagement, top-down institutional processes that allow little Indigenous voice, and lack of recognition of Indigenous culture and practices. Participants’ preferences for strategies to strengthen community adaptive capacity tended to be those that lead towards greater self-sufficiency, independence, empowerment, resilience and close contact with the natural environment. Based on the results, we developed a simple model to highlight main determinants of community vulnerability. A second model highlights components important in facilitating discourse on enhancing community capacity to adapt to climatic and other stressors. 相似文献
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Coastal northern Australia is largely owned and occupied by Aboriginal people who are strongly connected to their traditional country. We assess the views of Aboriginal people in Arnhem Land on the impacts of climate change and their possible precautionary responses to both sea level rise and a potential increase in the intensity of tropical cyclones in coastal communities. All respondents had heard about climate change, and 48 % had already seen environmental changes, particularly sea level rise, which they attributed to climate change. Fifty-eight percent of respondents would consider relocating in the future for safety reasons, although most respondents perceived living close to the sea as highly important for their future well-being, emphasising their strong connection to their traditional sea country. Many of those willing to relocate would consider moving inland, either temporarily or permanently, provided that community facilities could also be moved. Other respondents who said they would be unlikely to relocate in the future because of climate change impacts, and would prefer to adapt in situ with government support (e.g. building more shelters for severe cyclones, building sea walls and better roads for quick evacuation if necessary). We recommend that the diversity of adaptation preferences among Aboriginal people should be accommodated in policy to minimise social impacts of climate change and to take advantage of potential opportunities that could arise from moving. 相似文献
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Glen R. Walker Lu Zhang Tim W. Ellis Tom J. Hatton Cuan Petheram 《Hydrogeology Journal》2002,10(1):68-90
To manage dryland salinity, one needs to know how changed land use affects groundwater recharge. Few techniques are available
for comparing 'deep drainage' under different land uses. Soil-tracer methods, although good for replication and remote field
sites, are subject to spatial variability. Lysimeters are good for comparisons but are difficult for drier areas and sloping
land. Agronomic water-balance studies, where appropriate soil-water measurements exist, may be used with a soil-vegetation
model to estimate long-term deep drainage. Complex models are required to analyze specific land-use differences, such as perenniality
and root and leaf area dynamics, but models require intensive and extensive data for calibration. This approach is time-consuming,
labour-intensive, and difficult in remote locations. Because of the one-dimensionality of most soil-vegetation models and
the small fraction of the total water balance that is deep drainage, little success has occurred in extrapolating beyond the
research plot, or to spatially heterogeneous systems such as alley farming. Some 'top-down' modelling and landscape disaggregation
approaches have been partially successful in making catchment or regional-scale predictions. The direction for further work
depends on the level of recharge reduction that is required for most groundwater systems and difficulties that it imposes.
Electronic Publication 相似文献
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