Comment on the paper “CAWSES November 7–8, 2004, Superstorm: Complex Solar and Interplanetary Features in the Post-Solar Maximum Phase,” B. T. Tsurutani,E. Echer,F. L. Guarnieri,and J. U. Kozyra,Geophys. Res. Lett. 35 (2008)

The solar sources of the magnetic storms of November 8 and 10, 2004, are analyzed. The preliminary results of such an analysis [Yermolaev et al., 2005] are critically compared with the results of the paper [Tsurutani et al., 2008], where solar flares were put in correspondence with these magnetic storms. The method for determining solar sources that cause powerful magnetospheric storms is analyzed. It has been indicated that an optimal approach consists in considering coronal mass ejections (CMEs) as storm sources and accompanying flares as additional information about the location of CME origination.     

近70a泾河流域径流变化及其驱动因素研究

定量评价流域径流变化特征并开展其归因识别研究是应对气候变化实现水资源合理开发利用的基础.本研究以泾河流域为研究区,采用M-K检验、滑动t检验、小波分析等方法分析流域近70 a的水文气象要素变化特征,并基于Budyko假设评价气候变化和人类活动对径流变化的贡献率.结果表明:(1)泾河流域年径流深以0.41 mm·a-1的...     

The influence of rainfall and land use patterns on soil erosion in multi-scale watersheds: A case study in the hilly and gully area on the Loess Plateau,China

Soil erosion has become a major global environmental problem and is particularly acute on the Loess Plateau (LP), China. It is therefore highly important to control this process in order to improve ecosystems, protect ecological security, and maintain the harmonious relationship between humans and nature. We compared the effects of rainfall and land use (LU) patterns on soil erosion in different LP watersheds in this study in order to augment and improve soil erosion models. As most research on this theme has so far been focused on individual study areas, limited analyses of rainfall and LU patterns on soil erosion within different- scale watersheds has so far been performed, a discrepancy which might influence the simulation accuracies of soil erosion models. We therefore developed rainfall and LU pattern indices in this study using the soil erosion evaluation index as a reference and applied them to predict the extent of this process in different-scale watersheds, an approach which is likely to play a crucial role in enabling the comprehensive management of this phenomenon as well as the optimized design of LU patterns. The areas considered in this study included the Qingjian, Fenchuan, Yanhe, and Dali river watersheds. Results showed that the rainfall erosivity factor (R) tended to increase in these areas from 2006 to 2012, while the vegetation cover and management factor (C) tended to decrease. Results showed that as watershed area increased, the effect of rainfall pattern on soil erosion gradually decreased while patterns in LU trended in the opposite direction, as the relative proportion of woodland decreased and the different forms of steep slope vegetation cover became more homogenous. As watershed area increased, loose soil and craggy terrain properties led to additional gravitational erosion and enhanced the effects of both soil and topography.     

1985-2005年环渤海地区土地利用变化时空格局

Based on TM image data and other survey materials, this paper analyzed the spatiotemporal patterns of land use change in the Bohai Rim during 1985–2005. The findings of this study are summarized as follows: (1) Land use pattern changed dramatically during 1985–2005. Industrial and residential land in urban and rural areas increased by 643,946 hm², of which urban construction land had the largest and fastest increase of 294,953 hm² at an annual rate of 3.72%. (2) The outward migration of rural population did not prevent the expansion of residential land in rural areas by 184,869 hm². This increase reveals that construction of rural residences makes seriously wasteful and inefficient use of land. (3) Arable land, woodland and grassland decreased at a rate of −0.02%, −0.12% and −1.32% annually, while unused land shrank by 157,444 hm² at an annual rate of −1.69%. (4) The change of land use types showed marked fluctuations over the two stages (1985–1995 and 1995–2005). In particular, arable land, woodland and unused land experienced an inversed trend of change. (5) There was a significant interaction between arable land and woodland. Industrial construction land in urban and rural areas showed a net trend of increase during the earlier period, but only adjustment to its internal structure during the second period. The loss of arable land to the construction of factories, mines and residences took place mainly in the fringe areas of large and medium-sized cities, along the routes of major roads, as well as in the economically developed coastal areas in the east. Such changes are closely related to the spatial differentiation of the level of urbanization and industrialization in the region.     

Surface Oscillations of a Free-Falling Droplet of an Ideal Fluid

According to observations, drops freely falling in the air under the action of gravity are deformed and oscillate in a wide range of frequencies and scales. A technique for calculating surface axisymmetric oscillations of a deformed droplet in the linear approximation under the assumption that the amplitude and wavelength are small when compared to the droplet diameter is proposed. The basic form of an axisymmetric droplet is chosen from observations. The calculation results for surface oscillations agree with recorded data on the varying shape of water droplets falling in the air.     

淮河流域水文随机方法的径流图化(英文)

Theoretical difficulties for mapping and for estimating river regime characteristics in a large-scale basin remain because of the nature of the variable under study: river flows are related to a specific area, i.e. the drainage basin, and are hierarchically organized in space through the river network with upstream-downstream dependencies. Another limitation is there are not enough gauge stations in developing countries. This presentation aims at de-veloping the hydro-stochastic approach for producing choropleth maps of average annual runoff and computing mean discharge along the main river network for a large-scale basin. The approach applied to mean annual runoff is based on geostatistical interpolation proce-dures coupled with water balance and data uncertainty analyses. It is proved by an applica-tion in the upstream at Bengbu in the Huaihe River Basin, a typical large-scale basin in China. Hydro-stochasitic approach in a first step interpolates to a regular grid net and in a second step the grid values are integrated along rivers. The interpolation scheme includes a con-straint to be able to account for the lateral water balance along the rivers. Grid runoff map with 10 km × 10 km resolution and the discharge map along the river with the 1 km basic length unit are the main results in this study. This kind of statistic approach can be widely used be-cause it avoids the complexity of hydrological models and does not depend on the meteoro-logical data.     

Experimental research on physical properties of saline soil subgrade filler in Chaerhan region

In order to improve the engineering stability of saline soil of high chloride content in the Chaerhan salt lake region, six typical characteristics saline soil samples were selected, and tests on their...     

基于DEA和Malmquist的中国城市代谢效率研究

运用物质流、数据包络分析(DEA)及Malmquist指数对中国31个案例城市进行了城市代谢效率的研究。通过将城市代谢系统社会经济产出、环境非期望产出及水、电、化石能源、金属矿物、建筑材料、食物等投入部分纳入进DEA和Malmquist指数中,测得了案例城市的2000年、2010年代谢效率及变化趋势。研究结果发现,中国城市代谢系统效率总体相对较高,尤其是东中部地区城市的综合效率、纯技术效率和规模效率要高于西部地区城市,大城市的代谢综合效率高于巨型、超大和特大城市。2000~2010年,城市代谢综合效率、纯技术效率等所有效率指标的均值均呈现出下降趋势,但是中、西部地区城市的综合效率和纯技术效率却呈改善趋势,并且特大和超大城市的综合效率高于巨型城市。     

Fuzzy cluster analysis in geochemical exploration

As a classification method, cluster analysis has been widely used in geology and geochemical exploration, but sometimes the results of clustering were difficult to interpret, or missclassification of geochemically similar members into entirely different clusters might occur. The reason for this is suggested and discussed. A new technique, fuzzy clustering is introduced. Comparision of the results of fuzzy clustering with conventional clustering using a set of hypothetical data is made. An example of a practical application indicating the apparent merits of fuzzy clustering is given. This technique might show great promise when applicated to geochemical exploration problems.