岸线码头密度对河道水动力和污染物输移影响分析——以武汉河段为例

为研究岸线码头密度对河流水动力变化及污染物输移的影响,以武汉河段为例,基于Mike21模型建立了适用于该河段的平面二维水动力-水质模型,计算了长为9.6 km的岸线范围内布置不同密度码头群后引起的附近区域内水位、流速变化以及突发水污染事故后的自净能力变化,从空间差异性、最大变幅等角度对比了三者的差异,并归纳了码头密度与水动力条件、污染物浓度变幅之间的关系.结果 表明:(1)随着码头密度增加,工程区上游水位变化较流速更敏感,工程区及下游局部位置水位变幅较小,而流速变化较为敏感,表现为前沿主流区流速增大,近岸区流速减小;当码头密度大于1.25～2.5座/km的临界范围后,水动力条件随码头密度的变幅逐渐减缓.(2)修建码头后,受水动力变化影响,工程区河段上游污染物浓度变化呈"峰前减、峰后增",但工程区下游呈"峰前增、峰后减"的特征;工程区间内表现为主流区浓度增大、近岸带浓度减小、高浓度滞留时间总体增加的变化特点.(3)受码头工程群影响,无论是区间整体上,还是局部范围内,污染物浓度相对水动力条件变幅更大,对河段内水源地的取水可能造成不利影响.以上认识对于河流岸线开发利用规模选取和效应评估具有参考意义.     

湖北九宫山甜槠群落结构与优势种的空间分布格局研究

通过对湖北九宫山国家级自然保护区甜槠群落建立的1ha固定森林样地进行植物群落调查,分析了样地内木本植物物种组成、区系成分、种群径级结构和空间分布格局,结果表明:(1)样地内木本植物(DBH≥1 cm)共有132种,隶属于42科78属,其中,杜鹃花科、壳斗科、樟科、蔷薇科、冬青科等是优势科,短柄袍、鹿角杜鹃、青冈、长叶石栎、甜槠等是优势种.(2)样地内植物科、属的分布类型均以泛热带分布类型为主,分别为30.95％和20.51％.(3)样地内所有木本植物个体的径级结构均呈倒"J"型,幼龄个体数量大,森林群落更新状况良好.(4)样地内木本植物个体的空间分布格局以聚集分布为主,部分优势物种在小尺度上呈聚集分布,而在较大尺度上则为随机分布.     

A comparison analysis of the decoupling carbon emissions from economic growth in three industries of Heilongjiang province in China

Environmental Science and Pollution Research - Growing environmental pressure urges China to develop in a sustainable and low carbon way, and thus China strives to achieve a carbon peak by 2030 and...     

Research progress and hot spots of hydrothermal liquefaction for bio-oil production based on bibliometric analysis

Environmental Science and Pollution Research - Hydrothermal liquefaction (HTL) of biomass used HTL reaction under high temperature and pressure to produce bio-oil. This technology is considered as...     

A comprehensive review on green buildings research: bibliometric analysis during 1998–2018

Environmental Science and Pollution Research - Buildings account for nearly 2/5ths of global energy expenditure. Due to this figure, the 90s witnessed the rise of green buildings (GBs) that were...     

Characteristics analysis of near-field and far-field aerodynamic noise around high-speed railway bridge

Environmental Science and Pollution Research - The aerodynamic noise around the high-speed railway bridge is studied by the train-bridge-flow field numerical model and theory analysis. With the...     

Magnetic graphene-based nanocomposites as highly efficient absorbents for Cr(VI) removal from wastewater

Environmental Science and Pollution Research - Due to the merits of their high adsorption and convenient separation, magnetic graphene-based composites have become a promising adsorbent in terms of...     

Could biochar amendment be a tool to improve soil availability and plant uptake of phosphorus? A meta-analysis of published experiments

Environmental Science and Pollution Research - As one of the most important nutrients for plant growth, phosphorus was often poorly available in soil. While biochar addition induced improvement of...     

Correction to: Impact of precipitation disparity on groundwater fluctuation in a semi-arid region (Vellore district) of southern India using geospatial techniques

Environmental Science and Pollution Research - A Correction to this paper has been published: https://doi.org/10.1007/s11356-021-13406-7     

Lithium extraction from salt lake brines with high magnesium/lithium ratio: a review

Environmental Chemistry Letters - The demand for lithium is growing rapidly with the increase in electric vehicles, batteries and electronic equipments. Lithium can be extracted from brines, yet...