作为水生态保护与修复的重要理论,鱼类栖息地健康评价一直是研究重点,但缺少量化综合评价的深入研究。以长江上游中的5处典型深潭生境为例,构建了鱼类栖息地健康状况量化评价体系。研究通过长江上游典型深潭生境健康评价(一级指标)为基...作为水生态保护与修复的重要理论,鱼类栖息地健康评价一直是研究重点,但缺少量化综合评价的深入研究。以长江上游中的5处典型深潭生境为例,构建了鱼类栖息地健康状况量化评价体系。研究通过长江上游典型深潭生境健康评价(一级指标)为基准,分为了栖息地环境和栖息地功能(二级指标),涵盖了水质特性、生物环境、水文环境、鱼类资源状况、栖息地质量5个三级指标以及29个四级指标,基于熵权法构建栖息地健康综合评价数学模型,通过栖息地健康综合指数(Comprehensive Health Indicator,ρ)表征典型栖息地健康状态,并对其健康状况进行综合评价。研究结果表明:长江上游典型深潭生境有1处健康等级评价为Ⅰ级,处于非常健康状态;3处评价为Ⅱ级,处于健康状态;1处评价为Ⅲ级,处于亚健康状态,无不健康或劣汰的点。总体来看,长江上游典型栖息地基本处于健康状态,且表现出较强的空间异质性,该评价结果在一定程度上客观反映了长江上游典型栖息地的健康状况,最后根据评分等级探讨了长江上游鱼类栖息地生态系统中亟需解决的问题,针对性地提出了生境修复的对策与建议。展开更多
目的优化三七茎叶-桑叶(stems and leaves of Panax notoginseng-leaves of Morus alba L.,SLML)固体饮料的加工工艺,并考察其抗氧化活性。方法考察原料比例,优化浸提条件,经过浸提、浓缩、喷雾干燥制备SLML固体饮料,并测定其总皂苷含量...目的优化三七茎叶-桑叶(stems and leaves of Panax notoginseng-leaves of Morus alba L.,SLML)固体饮料的加工工艺,并考察其抗氧化活性。方法考察原料比例,优化浸提条件,经过浸提、浓缩、喷雾干燥制备SLML固体饮料,并测定其总皂苷含量及2,2-联氮-二(3-乙基-苯并噻唑啉-6-磺酸)二铵盐[2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)ammonium salt,ABTS^(+)·]、1,1-二苯基-2-三硝基苯肼[1,1-diphenyl-2-picrylhydrazyl,DPPH·]、超氧阴离子(O^(2‒)·)、羟基自由基(OH·)的清除率。结果在SLML的质量比(m:m)为7:3,20倍(m:V)食用酒精(49%,V:V)浸提49 h,浸提2次,过滤液浓缩至1/3体积,120℃喷雾干燥的条件下,制备出三七茎叶桑叶固体饮料的得粉率为37.74%。所得固体饮料具有清香、微苦、回甘等感官特性。检出人参皂苷Re(38.58 mg/g)、Rb3(40.82 mg/g)和三七皂苷Fd(26.40 mg/g)11种皂苷化合物;清除ABTS^(+)·、DPPH·、O^(2‒)·、OH·的半抑制浓度(half maximal inhibitory concentration,IC50)值分别为0.50、0.47、0.56、1.08 mg/mL。结论以三七茎叶、桑叶为原料开发得到一种风味良好具有抗氧化活性的固体饮料,具有一定的市场应用前景,可为云南特色食品的深度开发利用提供科学支撑。展开更多
Plant leaves may emit a substantial amount of volatile organic compounds （VOCs） into the atmosphere, which include isoprene, terpene, alkanes, alkenes, alcohols, aldehydes, eters, esters and carboxylic acids. Furthe...Plant leaves may emit a substantial amount of volatile organic compounds （VOCs） into the atmosphere, which include isoprene, terpene, alkanes, alkenes, alcohols, aldehydes, eters, esters and carboxylic acids. Furthermore, most of these compounds actively participate in tropospheric chemistry. Great progresses have been made in linking emission of these compounds to climate. However, the VOCs emission function in plant is still not clear. Recently, some evidence has emerged that the production and the emission of VOCs, such as isoprene and monoterpenes, which account for 80% of total VOCs, exhibit plant protection against high temperatures. These increases in VOCs emissions could contribule in a significant way to plant thermotolerance. This perspective summarizes some latest literatures regarding the VOCs emission-dependent thermoprotection in plant species subjected to high temperature stress, presents the achievement in studies concerning plant VOCs emission-dependent thermotolerance, and then exhibits the proposed mechanisms of such plant thermotolerance. Finally open questions regarding the plant VOCs emission were shown, and the future researches were proposed.展开更多
文摘作为水生态保护与修复的重要理论,鱼类栖息地健康评价一直是研究重点,但缺少量化综合评价的深入研究。以长江上游中的5处典型深潭生境为例,构建了鱼类栖息地健康状况量化评价体系。研究通过长江上游典型深潭生境健康评价(一级指标)为基准,分为了栖息地环境和栖息地功能(二级指标),涵盖了水质特性、生物环境、水文环境、鱼类资源状况、栖息地质量5个三级指标以及29个四级指标,基于熵权法构建栖息地健康综合评价数学模型,通过栖息地健康综合指数(Comprehensive Health Indicator,ρ)表征典型栖息地健康状态,并对其健康状况进行综合评价。研究结果表明:长江上游典型深潭生境有1处健康等级评价为Ⅰ级,处于非常健康状态;3处评价为Ⅱ级,处于健康状态;1处评价为Ⅲ级,处于亚健康状态,无不健康或劣汰的点。总体来看,长江上游典型栖息地基本处于健康状态,且表现出较强的空间异质性,该评价结果在一定程度上客观反映了长江上游典型栖息地的健康状况,最后根据评分等级探讨了长江上游鱼类栖息地生态系统中亟需解决的问题,针对性地提出了生境修复的对策与建议。
文摘目的优化三七茎叶-桑叶(stems and leaves of Panax notoginseng-leaves of Morus alba L.,SLML)固体饮料的加工工艺,并考察其抗氧化活性。方法考察原料比例,优化浸提条件,经过浸提、浓缩、喷雾干燥制备SLML固体饮料,并测定其总皂苷含量及2,2-联氮-二(3-乙基-苯并噻唑啉-6-磺酸)二铵盐[2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)ammonium salt,ABTS^(+)·]、1,1-二苯基-2-三硝基苯肼[1,1-diphenyl-2-picrylhydrazyl,DPPH·]、超氧阴离子(O^(2‒)·)、羟基自由基(OH·)的清除率。结果在SLML的质量比(m:m)为7:3,20倍(m:V)食用酒精(49%,V:V)浸提49 h,浸提2次,过滤液浓缩至1/3体积,120℃喷雾干燥的条件下,制备出三七茎叶桑叶固体饮料的得粉率为37.74%。所得固体饮料具有清香、微苦、回甘等感官特性。检出人参皂苷Re(38.58 mg/g)、Rb3(40.82 mg/g)和三七皂苷Fd(26.40 mg/g)11种皂苷化合物;清除ABTS^(+)·、DPPH·、O^(2‒)·、OH·的半抑制浓度(half maximal inhibitory concentration,IC50)值分别为0.50、0.47、0.56、1.08 mg/mL。结论以三七茎叶、桑叶为原料开发得到一种风味良好具有抗氧化活性的固体饮料,具有一定的市场应用前景,可为云南特色食品的深度开发利用提供科学支撑。
文摘Plant leaves may emit a substantial amount of volatile organic compounds （VOCs） into the atmosphere, which include isoprene, terpene, alkanes, alkenes, alcohols, aldehydes, eters, esters and carboxylic acids. Furthermore, most of these compounds actively participate in tropospheric chemistry. Great progresses have been made in linking emission of these compounds to climate. However, the VOCs emission function in plant is still not clear. Recently, some evidence has emerged that the production and the emission of VOCs, such as isoprene and monoterpenes, which account for 80% of total VOCs, exhibit plant protection against high temperatures. These increases in VOCs emissions could contribule in a significant way to plant thermotolerance. This perspective summarizes some latest literatures regarding the VOCs emission-dependent thermoprotection in plant species subjected to high temperature stress, presents the achievement in studies concerning plant VOCs emission-dependent thermotolerance, and then exhibits the proposed mechanisms of such plant thermotolerance. Finally open questions regarding the plant VOCs emission were shown, and the future researches were proposed.
