An understanding of geography: The perspectives of English primary trainee teachers

There have been few studies of trainee teachers' conceptions of the term ‘geography’. Building on these, this study identifies a number of conceptions of geography held by primary school trainee teachers in England. Their ideas are compared with their understanding of the reasons for teaching geography to young children. Similar outcomes emerge. While a small number of primary trainee teachers see geography education as concerned with the study of places, a slightly larger group view teaching geography as developing children's sense of responsibility for the earth and its people. However, by far the largest groups of students perceive geography's role to be to develop younger children's awareness and knowledge of the environment. Additionally, a sizeable group of trainees see geography as providing knowledge about the features and countries of the world. The implications of these findings are considered for the brief geography study units which primary teacher trainees take as part of their initial teacher training programme in English higher education. The conclusion is that it is important to widen primary trainee teachers' perspectives during even the briefest of units, not least to enable them to teach the national curriculum requirements for geography in primary schools. This revised version was published online in August 2006 with corrections to the Cover Date.     

江西金山金矿床深部原生晕特征与成矿预测

对江西金山金矿床深部扩建工程的0、-80、-10 m三个中段Au等元素原生晕的空间分布特征及组合特征进行研究表明,矿床原生晕组合复杂,各指示元素原生晕吻合性好,As与Au关系密切,是金矿化的最佳指示元素; As、Hg、Sb前缘晕指示元素与Bi、Mo等尾晕指示元素相互叠加,且平均异常强度较高,预测矿体应向深部延伸出现第二个富集带,具有很大的工业远景;到-10m中段Au矿化减弱,Cu矿化增强,燕山早期岩浆热液的叠加改造作用明显,在深部可能出现Cu、Au叠加矿床.     

主体结构隔震的二次结构减振分析

二次结构常常在大震甚至中小地震中发生损坏或中断工作，急需寻找安全有效的设计方法。对一幢典型结构，考虑不同场地条件、主体结构隔震以及二次结构不同阻尼比的影响，计算各层的楼面绝对加速度与相对位移反应谱。分析表明，主体结构隔震或同时增大二次结构阻尼是取得二次结构较好减振效果的有效途径，主体结构的隔震阻尼不宜太大，主体结构隔震后二次结构对所在楼层位置的敏感性大大降低。     

陕西省凤县铅硐山大型铅锌矿床原生异常分带及分带指数

经对陕西省凤县铅硐山矿床原生异常的分带性及分带指数进行研究，认为铅硐山矿床原生异常具有明显的分带性，全向序列(从上到下)为：SHg—Zn—THg—Asn—Cd—(Cu—Ga、Ge)—Pb—Ag—As2、Au。分带指数具有明显变化规律，分带指数可用于深部及外围成矿预测。     

Dynamic change of net primary productivity and fractional vegetation cover in the yellow river Basin using multi-temporal AVHRR NDVI Data

An exponential relationship between net primary productivity (NPP) and integrated NDVI has been found in this paper. Based on the relationship and using multi-temporal 8 km resolution NOAA AVHRR-NDVI data, the spatial distribution and dynamic change of NPP and fractional vegetation cover in the Yellow River Basin from 1982 to 1999 are analyzed. Finally, the effect of rainfall on NDVI is examined. Results show that mean NPP and fractional vegetation cover have an inclining trend for the whole basin, and rainfall in flood season influences vegetation cover most.     

Application of the geographical information systems approach to watershed mass balance studies

This study was undertaken to test the utility of a geographical information systems (GIS) approach to problems of watershed mass balance. This approach proved most useful in exploring the effects that watershed scale, lithology and land use have on chemical weathering rates, and in assessing whether mass balance calculations could be applied to large multilithological watersheds. Water quality data from 52 stations were retrieved from STORET and a complete GIS database consisting of the watershed divide, lithology and land use was compiled for each station. Water quality data were also obtained from 7 experimental watersheds to develop a methodology to estimate annual fluxes from incomplete data sets. The methodology consists of preparing a composite of daily flux data, calculating a best fit sinusoid and integrating the equation to obtain an annual flux. Comparison with annual fluxes calculated from high resolution data sets suggests that this method predicts fluxes within about 10% of the true annual flux. Annual magnesium fluxes (moles km⁻² yr⁻¹) were calculated for all stations and adjusted for fluxes from atmospheric deposition. Magnesium flux was found to be a strong function of the amount of carbonate in the watershed, and silica fluxes were found to increase with the fraction of sandstone present in the watershed. All fluxes were strongly influenced by mining practices, with magnesium fluxes from affected watersheds being 6–10 times higher than fluxes from comparable pristine watersheds. Mining practices enhance chemical weathering by increasing the surface area of unweathered rock to which water has access and by increasing acidity and rate of mineral weathering. Fluxes were also found to increase with watershed size. This scale dependence is most likely caused by the sensitivity of weathering fluxes to even minor quantities of carbonates, which are likely to be found in all lithologies at larger scales. Mass balances were carried out in watersheds where gauged sub-watersheds made up more than 95% of the area. The calculations show large magnesium flux and water balance discrepancies. These errors may be a result of significant groundwater inputs to streams between gauges. The results suggest that improvements in how we measure discharge and estimate fluxes may be required before we can apply mass balance techniques to larger scales. © 1997 John Wiley & Sons, Ltd.     

Comparison of methods for calculating annual solute exports from six forested appalachian watersheds

Six methods were compared for calculating annual stream exports of sulfate, nitrate, calcium, magnesium and aluminum from six small Appalachian watersheds. Approximately 250–400 stream samples and concurrent stream flow measurements were collected during baseflows and storm flows for the 1989 water year at five Pennsylvania watersheds and during the 1989–1992 water years at a West Virginia watershed. Continuous stream flow records were also collected at each watershed. Solute exports were calculated from the complete data set using six different scenarios ranging from instantaneous monthly measurements of stream chemistry and stream flow, to intensive monitoring of storm flow events and multiple regression equations. The results for five of the methods were compared with the regression method because statistically significant models were developed and the regression equations allowed for prediction of solute concentrations during unsampled storm flows. Results indicated that continuous stream flow measurement was critical to producing exports within 10% of regression estimates. For solutes whose concentrations were not correlated strongly with stream flow, weekly grab samples combined with continuous records of stream flow were sufficient to produce export estimates within 10% of the regression method. For solutes whose concentrations were correlated strongly with stream flow, more intensive sampling during storm flows or the use of multiple regression equations were the most appropriate methods, especially for watersheds where stream flows changed most quickly. Concentration–stream flow relationships, stream hydrological response, available resources and required level of accuracy of chemical budgets should be considered when choosing a method for calculating solute exports. © 1997 John Wiley & Sons, Ltd.     

全球FLUXNET站点总初级生产力的年际变化及其主导因子解析

基于耶鲁互动生物圈模式（YIBs）,结合FLUXNET网络观测时间超过8 a的站点的观测数据,研究对不同气象因子影响下总初级生产力（Gross Primary Productivity,GPP）的年际变化进行分析,探讨各植被类型GPP年际变化的主要驱动因子。结果表明,光合有效辐射的变化是落叶阔叶林和常绿针叶林站点GPP年际变化的主要驱动因子,贡献了这些森林类型年际变率的80%。相对湿度变化是作物站点GPP年际变化的主要驱动因子,贡献了作物GPP年际变率的65%。温度是灌木丛站点GPP年际变率的重要因子,其贡献率达到58%。草原站点GPP年际变化的不确定性较大,没有统一的主导因子。研究结果表明,气象要素是全球陆地GPP年际变化的主导因素。在未来气候变化背景下,极端气候事件频发可能会进一步增加GPP的年际变率。     

Distributions of chlorophyll a and carbon fixed strength of phyto-plankton in autumn of the southern Huanghai Sea waters

1IntroductionRecently,the increasing carbon dioxide(CO2)in the atmosphere is viewed by many as perhaps themost serious global environment problemfacing man-kind.Numerous studies and surveys aiming at theglobal CO2flux therefore,have been made to esti-mate…     

中国近海初级生产力的遥感研究及其时空演化

利用分级初级生产力模式反演估算了2003~2005年0^o~41^oN,105^o~130^oE海域的初级生产力,并分析了它们的时空演化。同时还计算了该时段内渤海、北黄海和南黄海、东海北部和南部以及南海的平均初级生产力状况,结果得出它们的年平均初级生产力 (2003~2005年) 分别为564.39、363.08、536.47、413.88、195.77和100.09 gCm^-2a^-1。北黄海、南黄海及东海南部的初级生产力分别在春季 (4~6月) 和秋季 (10、11月) 出现两次峰值,且春季的峰值高于秋季。然而,南海的两个峰值则分别出现在冬季 (1月)和夏季 (8月),且冬季的峰值高于夏季。渤海和东海北部则呈现单峰 (6月) 分布。渤海和南黄海的初级生产力几乎在整年内都高于其它海域,而东海南部和南海的初级生产力则在整年内都低于其他海域。其中,南海的初级生产力最低,月平均全都低于400 mgCm^-2d^-1。除南海以外的其它5个海域,在春季时期 (东海南部为3~6月,其他海域为4~7月) 的初级生产力最高,平均约占年平均值的41%,其年际变化也最大,平均标准偏差为6.68;而秋季时期 (东海南部为10~1月,其他海域为8~11月) 对年平均的贡献也很大,平均约33%;其他月份 (东海南部为2月和7-9月,其他海域为12~3月) 的贡献则最小。南海的初级生产力则在冬季时期 (12~3月) 最高,约占年平均的42%,夏末秋季 (8~11月) 次之,约30%,春季时期 (4~7月) 最低。叶绿素-a、海表温度、光合有效辐射、季风活动、河流排放、上升流、黑潮以及沿岸流等物理-化学环境因子是造成中国近海初级生产力时空演化的主要原因。