地理学科价值观在教材中的渗透——以人教版高中必修地理1新教材为例

地理学科价值观蕴含在丰富的地理教材中,人教版高中必修地理1新教材是新课改背景下编写的教材,也是学生进入高中后接触到的首本地理教材。因此,如何在教材中渗透学科价值观成为关键问题。本文将从地理学科六个层面的价值观出发,对教材进行梳理与研究。以"何时‘蓝天’常在"为例进行具体分析,为教师对新教材的理解与教学过程的实施提供参考依据,为凸显新教材在课程改革中的重要地位提供更多可思考的路径。     

海州湾底层鱼类物种多样性与生物量的关系

随着生物多样性的丧失,全球许多海洋生态系统的功能发生了显著变化。为了解生物多样性和生态系统功能之间的关系,科学的海洋生态保护与管理显得尤为重要。本研究根据2013−2022年春季在海州湾及其邻近海域进行的底拖网调查数据,基于结构方程模型（SEM）探究了底栖鱼类群落中环境因素、生物多样性（物种丰富度与均匀度）和生态系统功能指标（以总生物量表示）之间的关系。结果表明：物种丰富度和生物量之间存在显著的正相关,而均匀度和生物量存在显著的负相关。环境因素中盐度对物种丰富度和生物量均有显著的影响,而对于温度来说,夏季与冬季的温度比年平均温度对生物量的影响更强烈。本研究表明,生态位互补效应和选择效应这两种机制可能同时对维持海州湾底层鱼类群落中的生物多样性−生物量关系发挥了作用,此外这种关系还依赖于它们所生存的环境和栖息条件。     

应用混合分布研究银川平原地下水埋深对植被的影响

银川平原地处西北干旱地区,自然生态环境在西北地区具有典型性。研究银川平原的生态环境,需要研究植被,它反映多种因素的作用。在影响植被的各种因素中,地下水对植被生长的影响非常重要,但将地下水对植被生长的影响进行定量化分离并不容易。近年来,用混合分布函数处理大量数据的方法受到越来越多的关注,但是混合分布函数的参数求解一直比较困难。文章提出了一种基于混合分布函数和数据直方图之间的关系,用最小二乘法估计参数的新方法;并用这种方法,结合银川平原遥感数据中的归一化植被指数NDVI,对地下水埋深与植被生长的关系进行定量分析,得到地下水埋深对植被影响所服从的正态分布密度函数。     

南黄海北部前陆盆地的构造演化与油气突破

南黄海北部盆地是我国近海海域中唯一由中生代陆-陆碰撞造山作用形成的前陆盆地。其构造演化经历了4个阶段:(1)前造山期大陆边缘盆地阶段(Z—T2);(2)苏鲁造山带晚期前陆盆地阶段(J3—K);(3)造山期后陆内断陷盆地阶段(K2t—E);(4)区域沉降覆盖阶段(N—Q)。对其中陆内断陷盆地的详细调查研究结果表明,盆地内晚白垩世泰州组烃源岩发育,具有4套储盖组合,圈闭构造多,成藏配套条件好,计算其石油资源量约20×108t,是当前在南黄海获取油气重要突破的首选区域。     

石器功能研究的现代模拟实验: 石刀表面残留物中淀粉粒来源分析

淀粉粒分析在国内外环境考古学研究中得到了大量应用,但是目前国内还没有关于淀粉粒分析、石器功能与植物利用关系的现代过程研究。本研究针对石刀这一新石器时代重要的生产和生活工具开展现代过程的模拟实验,尝试利用淀粉粒分析方法验证石刀功能及其加工的植物类型。我们利用打制的简易石片模拟石刀,对未成熟和成熟的小麦(Triticum aestivum L.)进行了共两次割穗操作,提取并观察石片割穗后不同部位表面残留物中的淀粉粒形态及其组合。实验结果表明,石片表面残留物中的淀粉粒主要来源于小麦秸秆; 小麦秸秆淀粉粒的A型和B型淀粉粒(未成熟和成熟小麦秸秆淀粉粒——A+B型淀粉粒,含量分别为90.91 ％ 和92.59 ％ )分别与其成熟籽粒的A型和B型淀粉粒形态、大小相似,具备形态鉴定的特征; 小麦秸秆中还发现了独特的多面体型淀粉粒(未成熟和成熟小麦秸秆多面体型淀粉粒含量分别为9.09 ％ 和7.41 ％ ),这是小麦种子中缺少的类型。根据本次现代实验模拟的结果,考古遗址出土石刀上提取到的淀粉粒很可能来自于植物收割(或切削)过程的残留物,结合淀粉粒分析、石刀形制和出土状况进行分析,可以获取出土石刀功能与古人类植物利用的信息。     

松辽盆地深层侏罗系-下白垩统生物组合和沉积环境

本文描述了松辽盆地探井揭露的深层地层序列及其所产的5个牛物门类化石组合特征.9个孢粉组合是Monosulcites-Cyathidites组合、Pinaceae-Cyathidites-Osmundaeidites组合、Classopollis-Piceites组合、Lophotriletes-Cicatricosisporites组合、Paleoconiferus-Lygodiumsporites组合、Cyathidites-Leiotriletes-Clavatipollenites组合、Cicatricosisporites-Leiotriletes-Polyporopollenites组合、Leiotriletes-Schizaeoisporites-Classopollis组合和Trilobosporites-Cyathidites-Tricolpollenites组合.3个藻类组合是Vesperopsis-Australisphaera组合、Balmula granorugosa组合和Vesperopsis zhaodongensis组合.2个介形类组合是Cypridea unicostata-Limnocypridesadscondida组合和Mongolocypris limpida-Paracandona planiuscula组合.4个植物组合是Elatocladus submanchurica-Ginkgoites orientalis组合、Acanthopteris gothani-Pterophyllum组合、Sphenopteris johnstrupii-Coniopteris nympharum组合和Platanus septentrionalis-Protophyllum undulaturn组合.3个大孢子组合是Minerisporites sp.组合、Ricinospora leavigata-Galamospora sp.组合和Arcellites组合.还介绍了叶肢介、轮藻、双壳类和鱼类化石的产出情况.结合同位素资料认为：大庆群时代为中侏罗世,火石岭组可能为贝里阿斯期,沙河子组为凡兰吟期-欧特里夫期,营城组为欧特里夫期-巴列姆期,登娄库组为巴列姆期-阿普第期早期,泉头组一-二段为阿普第-阿尔卑期,并对各组沉积环境进行了初步分析.     

A probabilistic approach for computing water retention of particulate systems from statistics of grain size and tessellated pore network

The paper offers an analytical determination of the hydraulic properties of an unsaturated soil with reference to its retention curve, which describes the relationship between the volumetric water content and capillarity through matric suction. The analysis combines a particulate approach focused on the physics at the pore scale, including microstructural aspects, with a probabilistic approach where the void space and grain size are considered as random variables. In the end, the soil water characteristic curve of an unsaturated granular medium along a drying path can be derived analytically based on the sole information of particle size distribution. The analysis hinges on the tessellation of a wet granular system into an assemblage of tetrahedral unit cells revealing a pore network upon which capillary physics are computed with respect to pore throat invasion by a non-wetting fluid with evolving pendular capillary bridges. The crux of the paper is to pass from particle size probability distribution to a matching void space distribution to eventually reveal key information such as void cell and solid volume statistics. Making reasonable statistically based assumptions to render calculations tractable, the water retention curve can be readily constructed. Model predictions compare quite favourably with experimental data available for actual soils, especially in the high saturation range. Having a sound scientific basis, the model can be made amenable to address a variety of soils with a wider range of particle sizes.     

Micromechanical approach to swelling behavior of capillary-porous media with coupled physics

A detailed multiscale analysis is presented of the swelling phenomenon in unsaturated clay-rich materials in the linear regime through homogenization. Herein, the structural complexity of the material is formulated as a three-scale, triple porosity medium within which microstructural information is transmitted across the various scales, leading ultimately to an enriched stress-deformation relation at the macroscopic scale. As a side note, such derived relationship leads to a tensorial stress partitioning that is reminiscent of a Terzaghi-like effective stress measure. Otherwise, a major result that stands out from previous works is the explicit expression of swelling stress and capillary stress in terms of micromechanical interactions at the very fine scale down to the clay platelet level, along with capillary stress emerging due to interactions between fluid phases at the different scales, including surface tension, pore size, and morphology. More importantly, the swelling stress is correlated with the disjoining forces due to electrochemical effects of charged ions on clay minerals and van der Waals forces at the nanoscale. The resulting analytical expressions also elucidate the role of the various physics in the deformational behavior of clayey material. Finally, the capability of the proposed formulation in capturing salient behaviors of unsaturated expansive clays is illustrated through some numerical examples.     

An analytical study on three‐dimensional versus two‐dimensional water table‐induced flow patterns in a Tóthian basin

Although it has been increasingly acknowledged that groundwater flow pattern is complicated in the three‐dimensional (3‐D) domain, two‐dimensional (2‐D) water table‐induced flow models are still widely used to delineate basin‐scale groundwater circulation. However, the validity of 2‐D cross‐sectional flow field induced by water table has been seldom examined. Here, we derive the analytical solution of 3‐D water table‐induced hydraulic head in a Tóthian basin and then examine the validity of 2‐D cross‐sectional models by comparing the flow fields of selected cross sections calculated by the 2‐D cross‐sectional model with those by the 3‐D model, which represents the “true” cases. For cross sections in the recharge or discharge area of the 3‐D basin, even if head difference is not significant, the 2‐D cross‐sectional models result in flow patterns absolutely different from the true ones. For the cross section following the principal direction of groundwater flow, although 2‐D cross‐sectional models would overestimate the penetrating depth of local flow systems and underestimate the recharge/discharge flux, the flow pattern from the cross‐sectional model is similar to the true one and could be close enough to the true one by adjusting the decay exponent and anisotropy ratio of permeability. Consequently, to determine whether a 2‐D cross‐sectional model is applicable, a comparison of hydraulic head difference between 2‐D and 3‐D solutions is not enough. Instead, the similarity of flow pattern should be considered to determine whether a cross‐sectional model is applicable. This study improves understanding of groundwater flow induced by more natural water table undulations in the 3‐D domain and the limitations of 2‐D models accounting for cross‐sectional water table undulation only.