莱州湾南岸陆海交互地层间隙水有色溶解有机物的光谱特征研究

陆海交互区较高的固碳效率和较大的固碳潜力是在自然条件下长期解决气候变化和实现“碳达峰”“碳中和”的重要方案。为揭示莱州湾南岸陆海交互层中溶解有机物的来源和赋存形式,丰富对陆海交互区的碳源和碳汇的认识,于2021年11~12月采集钻孔岩心间隙水,分析其有色溶解有机物的紫外可见吸收光谱和三维荧光光谱。分析结果表明,溶解有机碳与a(320)均呈现出第二次海侵后变化大、浓度高的特征,陆相间隙水溶解有机物组成和性质差别大于海相间隙水。经平行因子分析法鉴别和OpenFlour匹配的5种荧光组分中,除底层外,类腐殖质组分贡献为总荧光强度的77%。荧光指数和自生源指数表明岩心间隙水有色溶解有机物由微生物再生产活动贡献为主,埋藏越久,微生物贡献越为显著,陆相层和海相层没有明显差别。主成分分析结果表明,不同沉积阶段溶解有机物组成存在一定差别,但随着沉积过程的发生,间隙水溶解有机物组成和性质逐渐趋同。长时间尺度下腐殖质高度成熟。

珠江三角洲土壤镉高含量区的化学形态特征

珠江三角洲冲积平原区存在镉的高含量区,其主要分布于第四纪海陆和陆海交互相。第四纪不同沉积相镉的全量和不稳定相态的含量特征也存在显著的差异,海陆交互相、陆海交互相、陆相的全量和不稳定相态的含量呈逐渐降低的趋势。从地表至深部,在地下水位附近不稳定相态的含量比例相对较大。

Analysis of the mechanical property of mudstone/shale in paralic coal measures and its influence factors

The mechanical property of mudstone/shale in coal measures is a key factor of engineering mechanics that influences the development of shale gas. A rock mechanics test was performed in order to analyze the complete stress-strain mechanic characteristics and influence factors of mudstone/shale in paralic coal measures, from the Carboniferous-Permian periods in a coal field of Northern China. The relationship between the mechanical properties of mudstone/shale in coal measures, and its chemical component, water content are established, and their models are constructed. Research results show that mud- stone/shale has low mechanical strength, low elastic modulus and a high Poisson＇s ratio. The complete stress-strain curve has apparent elastoplastic deformation characteristics, and after reaching peak strength, it exhibits obvious strain softening characteristics. The uniaxial compressive strength of mudstone/shale and its elastic modulus increases exponentially with the increase of SiO2 content, and as the ignition loss increases, the uniaxial compressive strength and elastic modulus of mudstone/shale will decrease according to the law of power function. The compressive strength of mudstone/shale and its elastic modulus will decrease with the increase of water content in mudstone/shale.

基于陆海统筹的南通市国土空间开发适宜性评价

以陆海统筹视角评价国土空间开发适宜性对于促进海洋资源合理利用及海洋经济可持续发展具有重要意义。本文以江苏省南通市为例,建立陆海一体的开发适宜性评价分类方案;基于短板效应,构建并计算两级开发适宜性评价体系;基于长板效应,叠置二级评价得分,获得一级开发适宜性评价结果。结论表明:①叠置二级评价结果后,海域建设适宜及农业适宜结果得到修正,总体二者高适宜区及低适宜区未发生明显变化,一般及较高适宜区变化较多。②短板效应理论确保了刚性管控线划定的区域适宜性得分不变,从而落实底线区域优先保护原则;长板效应对一级开发适宜性评价结果中一般适宜区与较高适宜区影响明显;③城镇、农业及生态空间面积分别占研究区总面积的23.17%、58.56%及18.27%,城镇空间形成3个陆海联动核心及2个内陆城市组团,农业空间集聚效应显著,生态空间成网状发展。构建二级开发适宜性评价体系,能够进一步厘清陆海可开发模式,贴近区域实际发展情况,提高3类空间划定精准度。

区域陆-水-气碳收支与碳平衡关键过程对地球系统碳中和的意义

衔接陆地-海洋的区域陆-水-气碳收支与碳平衡是地球系统碳中和的关键过程,因此定量解析陆-水-气的碳运移与碳交换协同过程对于深入理解陆地生态系统“丢失”的碳汇具有重要意义.本文集成分析了全球陆-海-气碳运移与碳收支变化及其影响机制,重点探讨内陆水体碳收支与碳循环过程在陆-水-气碳收支的重要作用,揭示全球变化下陆-水-气碳收支与碳平衡的调控机制,并进一步评估中国区域陆-水-气碳收支现状及其湖泊固碳潜力,提出定量人类活动对陆-水-气碳运移与碳交换过程的确切影响与幅度对于全球碳平衡与碳中和具有重要意义.