The microstructural and ultrastructural traits of three kinds of typical leaves of Populus euphratica Olive, including lanceolate, broad-ovate and dentate broad-ovate leaves, were studied by using electron microscope...The microstructural and ultrastructural traits of three kinds of typical leaves of Populus euphratica Olive, including lanceolate, broad-ovate and dentate broad-ovate leaves, were studied by using electron microscope and optical microscope. The re- sults showed that with the leaves changing from lanceolate shape to dentate broad-ovate shape, their structure obviously tended to be xeromorph: developed palisade tissue, undeveloped spongy tissue, thick cutin layer and sunken stomas. The amount of mitochondria tended to be increased, and the shape of chloroplasts varied from regular spindle to irregular rotundity or oval. The leaves were cov- ered with wax without cilium, and the stomas on the upper and lower epidermis of the leaves opened unevenly. The stomas on the lower epidermis were deeper than those on the upper epidermis under the scanning electron microscope. The results implied that the structural characteristics of the diversiform-leaves of P. euphratica are related to its eco-adaptability.展开更多
为揭示半干旱草原露天矿区生态环境质量状况,分离矿区人类活动生态累积效应并识别其演变态势,在厘清矿区生态累积效应概念的基础上,构建适用于半干旱草原的露天矿区生态环境质量评估指数(Surface Mining Areas Eco-environmental Evalua...为揭示半干旱草原露天矿区生态环境质量状况,分离矿区人类活动生态累积效应并识别其演变态势,在厘清矿区生态累积效应概念的基础上,构建适用于半干旱草原的露天矿区生态环境质量评估指数(Surface Mining Areas Eco-environmental Evaluation Index,SMAEEI)以及矿区生态累积效应定量评估模型。选取内蒙古胜利矿区为研究区,量化分析1986—2020年区域生态环境质量和生态累积效应的时空分布规律,以及主要人类活动的生态累积效应差异。结果表明:①SMAEEI适用于半干旱草原露天矿区,能客观呈现各地类生态环境质量高低顺序。35 a间研究区生态环境质量呈极显著下降趋势,且其空间差异显著减弱。露天矿场、城镇扩张区、锡林河湿地及北侧草地生态环境质量出现极显著、显著的退化趋势。②半干旱草原露天矿区生态累积效应定量评估模型能剔除气候因素对生态系统的耦合影响,分离并量化人类活动对矿区生态系统的累积效应,揭示累积的方向、程度和空间范围。35 a间研究区生态服务价值累积量(Change of Ecosystem Service Value Cumulant,COESVC)共减少1186157.03万元,出现负向生态累积效应,生态系统服务功能下降。高度、中度负向累积区集中在湿地和草地退化区、城镇区、露天矿场。③露天开采、城镇建设造成的单位面积负向生态累积效应最明显,前者在单位时间内带来的负向累积变化最剧烈,后者负向累积效应的局部影响程度和偏离度最大;放牧活动引起的负向生态累积效应影响范围最广、总量最大,但局部影响程度最小,生态系统服务功能较其余人类活动更稳定。研究成果可将矿区人类活动引起的生态环境实物量变动转化为价值量描述,为采用货币形式测算矿区生产生活行为的环境损害成本提供可行方法。展开更多
文摘The microstructural and ultrastructural traits of three kinds of typical leaves of Populus euphratica Olive, including lanceolate, broad-ovate and dentate broad-ovate leaves, were studied by using electron microscope and optical microscope. The re- sults showed that with the leaves changing from lanceolate shape to dentate broad-ovate shape, their structure obviously tended to be xeromorph: developed palisade tissue, undeveloped spongy tissue, thick cutin layer and sunken stomas. The amount of mitochondria tended to be increased, and the shape of chloroplasts varied from regular spindle to irregular rotundity or oval. The leaves were cov- ered with wax without cilium, and the stomas on the upper and lower epidermis of the leaves opened unevenly. The stomas on the lower epidermis were deeper than those on the upper epidermis under the scanning electron microscope. The results implied that the structural characteristics of the diversiform-leaves of P. euphratica are related to its eco-adaptability.
文摘为揭示半干旱草原露天矿区生态环境质量状况,分离矿区人类活动生态累积效应并识别其演变态势,在厘清矿区生态累积效应概念的基础上,构建适用于半干旱草原的露天矿区生态环境质量评估指数(Surface Mining Areas Eco-environmental Evaluation Index,SMAEEI)以及矿区生态累积效应定量评估模型。选取内蒙古胜利矿区为研究区,量化分析1986—2020年区域生态环境质量和生态累积效应的时空分布规律,以及主要人类活动的生态累积效应差异。结果表明:①SMAEEI适用于半干旱草原露天矿区,能客观呈现各地类生态环境质量高低顺序。35 a间研究区生态环境质量呈极显著下降趋势,且其空间差异显著减弱。露天矿场、城镇扩张区、锡林河湿地及北侧草地生态环境质量出现极显著、显著的退化趋势。②半干旱草原露天矿区生态累积效应定量评估模型能剔除气候因素对生态系统的耦合影响,分离并量化人类活动对矿区生态系统的累积效应,揭示累积的方向、程度和空间范围。35 a间研究区生态服务价值累积量(Change of Ecosystem Service Value Cumulant,COESVC)共减少1186157.03万元,出现负向生态累积效应,生态系统服务功能下降。高度、中度负向累积区集中在湿地和草地退化区、城镇区、露天矿场。③露天开采、城镇建设造成的单位面积负向生态累积效应最明显,前者在单位时间内带来的负向累积变化最剧烈,后者负向累积效应的局部影响程度和偏离度最大;放牧活动引起的负向生态累积效应影响范围最广、总量最大,但局部影响程度最小,生态系统服务功能较其余人类活动更稳定。研究成果可将矿区人类活动引起的生态环境实物量变动转化为价值量描述,为采用货币形式测算矿区生产生活行为的环境损害成本提供可行方法。
文摘干旱半干旱地区水资源缺乏,准确地计算区域生态环境用水和生态环境需水,可以对稀缺水资源进行合理调配,同时起到生态保护的作用。研究过程主要分为两个步骤:(1)采用RS技术,对新疆哈密地区1990年、2000年、2005年中巴资源一号卫星(China Brazil Earth Resources Sat-ellite)数据进行解译,形成1990年、2000年、2005年哈密地区土地覆被图形数据和相应的属性数据,确定相应年份各景观类型的面积;(2)参考有关研究并结合哈密地区实际情况,确定各景观类型的单位生态用水定额和需水定额,进而计算出1990年、2000年、2005年哈密地区的生态用水量,并以2005年哈密地区生态用水量为主要依据计算出保持哈密地区生态环境现状的生态需水量。研究结果表明,为了实现哈密地区生态环境整体保持在现状水平不致恶化、局部区域生态环境(巴里坤湖区)有所改善的生态治理目标,区域内生态环境需水总量为7.526×109m3,这一庞大的需水量将对该地区水资源配置造成巨大的压力;而当结合各类景观的地物空间位置特征进行分析时,发现该区域生态用(需)水量最大的景观(低覆盖草地)可以利用山地积雪融水进行自给,区域内实际需要规划配置的生态环境需水量为2.66×108m3,仅占区域生态环境需水总量的3.53%。在区域生态用(需)水计算过程中应考虑各种景观类型的生态用(需)水量的时空差异性,以保证水资源调配的科学与合理。
