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‘富有’甜柿中间砧的早期筛选和嫁接亲和性 被引量:8
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作者 汤丹 江锡兵 +3 位作者 龚榜初 刘同祥 徐阳 吴开云 《林业科学》 EI CAS CSCD 北大核心 2017年第5期54-62,共9页
【目的】通过研究‘富有’甜柿中间砧嫁接苗苗期生长、解剖等表现,筛选出早期亲和的嫁接组合,并探讨中间砧嫁接的亲和性机制。【方法】以浙江柿作基砧,‘兰溪大红柿’、‘南通小方柿’、‘次郎’和‘西村早生’作中间砧(设置10 cm和25 c... 【目的】通过研究‘富有’甜柿中间砧嫁接苗苗期生长、解剖等表现,筛选出早期亲和的嫁接组合,并探讨中间砧嫁接的亲和性机制。【方法】以浙江柿作基砧,‘兰溪大红柿’、‘南通小方柿’、‘次郎’和‘西村早生’作中间砧(设置10 cm和25 cm 2种长度),嫁接‘富有’接穗,对其苗期生长等表型性状和生理生化指标进行对比分析和综合评价;采用石蜡切片法和光学显微镜技术,观测各嫁接组合基砧-中间砧、中间砧-接穗嫁接口愈合情况。【结果】‘富有’甜柿嫁接苗因中间砧种类和长度不同,在苗期生长指标和解剖结构特征上存在明显差异。浙江柿直接嫁接‘富有’甜柿(对照)成活率、株高等表型性状和生理生化指标较差,且嫁接口存在明显的膨大(膨大指数R=0.980)、隔离层(隔离层产生比例G=88.9%)和导管堵塞(导管堵塞率D=16.3%)现象。4种中间砧中,以‘南通小方柿’和‘西村早生’作中间砧的2年生‘富有’甜柿嫁接苗株高、叶绿素总量、瞬时光合速率、叶片可溶性糖含量、根系可溶性糖含量和根系活力均极显著大于对照(P<0.05),成活率、茎段直径、叶片面积大于对照,且这2种中间砧明显降低植株嫁接口的R值、G值和D值。相同长度下,不同中间砧的嫁接苗生长指标综合评价值Q排序:‘南通小方柿’>‘西村早生’>‘次郎’>‘兰溪大红柿’。相同中间砧下,10 cm长度中间砧的组合成活率、株高、茎段直径、叶片面积和Q值大于25 cm中间砧的组合,R值、G值和D值则小于25 cm中间砧的组合。G值、D值与Q值极显著负相关(相关系数分别为-0.910,-0.977,P<0.01),表明嫁接口愈合情况直接影响嫁接苗早期表型生长和生理生化特性。【结论】浙江柿直接嫁接‘富有’甜柿早期不亲和。利用‘南通小方柿’和‘西村早生’作中间砧能改善嫁接口愈合情况,促进浙江柿嫁接‘富有’甜柿亲和;且以10 cm长度‘南通小方柿’作中间砧的‘富有’甜柿嫁接苗早期亲和性最好(Q=2.71,G=11.1%,D=0)。 展开更多
关键词 '富有’甜柿 嫁接 中间砧 亲和性 解剖结构
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不同材质果袋对‘富有’柿果生长发育的影响 被引量:6
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作者 胡青素 吴发荣 +2 位作者 龚榜初 马海泉 周仙根 《中南林业科技大学学报》 CAS CSCD 北大核心 2012年第5期35-41,共7页
为研究不同材质果袋对"富有"柿果实生长发育的影响,采用8种果袋于6月28日对柿果进行套袋处理,以不套袋为对照,通过定期采摘,观测不同套袋处理柿果内外指标的生长变化规律。结果表明:11月12日采收的果实硬度大、残次果率和褐... 为研究不同材质果袋对"富有"柿果实生长发育的影响,采用8种果袋于6月28日对柿果进行套袋处理,以不套袋为对照,通过定期采摘,观测不同套袋处理柿果内外指标的生长变化规律。结果表明:11月12日采收的果实硬度大、残次果率和褐斑率低,商品性好,提倡在该时期采收;在果实的生长发育过程中,外黄内黑双层袋和蓝色玻璃纸处理使果实单果质量、VC含量下降,残次果和褐斑发生率增加,黄色和红色玻璃纸处理使果实硬度明显下降、残次果率上升,无色玻璃纸处理使残次果和褐斑发生率均有较明显增加,外白内红和外黄内白双层纸处理虽然降低了残次果率,11月22日采收时分别比对照果低15.66%、14.14%,但其他品质下降较为明显,仍不宜提倡;白色单层纸袋内果实除SCC含量略高于对照外,其它内在品质均有所降低,但其果面光洁度好、着色均匀,11月12日采摘时其商品性优于对照,值得生产上采用。 展开更多
关键词 经济林学 '富有’ 套袋处理 生长发育 果实品质
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‘富有’柿果实韧皮部胞间连丝研究 被引量:5
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作者 刘林 《果树学报》 CAS CSCD 北大核心 2012年第5期872-876,共5页
【目的】果实韧皮部胞间连丝分布特点决定韧皮部同化物卸载途径类型,为了解‘富有’柿果实膨大期韧皮部胞间连丝分布特点,【方法】采用透射电子显微技术对膨大期果实韧皮部做超微结构研究,统计不同类型细胞界面上胞间连丝发生频率。【... 【目的】果实韧皮部胞间连丝分布特点决定韧皮部同化物卸载途径类型,为了解‘富有’柿果实膨大期韧皮部胞间连丝分布特点,【方法】采用透射电子显微技术对膨大期果实韧皮部做超微结构研究,统计不同类型细胞界面上胞间连丝发生频率。【结果】结果表明,柿果实维管束没有维管束鞘,直接与果肉细胞连接,韧皮部由筛管分子、伴胞和维管薄壁细胞构成,筛管-伴胞界面、伴胞-维管薄壁细胞界面、维管薄壁细胞-维管薄壁细胞界面以及维管薄壁细胞-果肉细胞界面上都存在胞间连丝,伴胞-维管薄壁细胞界面上的胞间连丝发生频率约为维管薄壁细胞-果肉细胞界面上的一半。【结论】据此认为,‘富有’柿果实韧皮部伴胞与维管薄壁细胞界面上分布有中等数量的胞间连丝,显示韧皮部卸载途径为共质体类型。 展开更多
关键词 '富有’ 果实 韧皮部 胞间连丝 超微结构
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‘富有’甜柿砧木种质早期亲和性研究 被引量:1
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作者 石建城 魏平 +5 位作者 王孟珂 聂梦瑶 吴俊瑶 王仁梓 杨勇 关长飞 《中国果树》 北大核心 2020年第2期53-57,共5页
以25个柿砧木为材料,对‘富有’甜柿进行嫁接亲和力比较试验,通过连续多年观测多项生理生化指标,并辅以数学多元统计的方法,分析比较不同砧木嫁接‘富有’甜柿后生长差异情况,评价不同砧木嫁接‘富有’甜柿的亲和性,初步筛选并获得具有... 以25个柿砧木为材料,对‘富有’甜柿进行嫁接亲和力比较试验,通过连续多年观测多项生理生化指标,并辅以数学多元统计的方法,分析比较不同砧木嫁接‘富有’甜柿后生长差异情况,评价不同砧木嫁接‘富有’甜柿的亲和性,初步筛选并获得具有推广潜力的‘富有’系亲和性砧木。结果表明,柿不同近缘种嫁接‘富有’甜柿的嫁接成活率、嫁接保存率、嫁接口愈合情况差异显著,本砧嫁接’富有‘甜柿嫁接亲和性相对稳定,不因本砧品种而异。综合评价结果表明,君迁子824和君迁子848与’富有‘的早期亲和性较好。 展开更多
关键词 砧木 '富有’ 嫁接 亲和性
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不同材质果袋对‘富有’柿果色泽形成和色素积累的影响 被引量:1
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作者 胡青素 龚榜初 +3 位作者 赖俊声 马海泉 程亚平 吴小林 《西南林业大学学报(自然科学)》 CAS 2013年第3期37-44,共8页
为探讨不同材质果袋对柿果色泽形成和色素积累的影响,采用4种玻璃纸袋和生产上常用的3种纸袋,于6月25日对‘富有’柿果进行套袋处理,以不套袋为对照,分别在8月25日、9月10日、9月20日、10月2日、10月12日、10月25日、11月2日、11月12日... 为探讨不同材质果袋对柿果色泽形成和色素积累的影响,采用4种玻璃纸袋和生产上常用的3种纸袋,于6月25日对‘富有’柿果进行套袋处理,以不套袋为对照,分别在8月25日、9月10日、9月20日、10月2日、10月12日、10月25日、11月2日、11月12日等8个不同时期分次采摘。结果表明:早期柿果在遮光性强的环境下果皮中叶绿素含量下降明显,果实提前褪绿;10月2日至11月2日是柿果转色的关键时期,色泽均从绿色转化到橙色、橙红色,套袋对类胡萝卜素含量的影响主要集中在此阶段;色泽L值与a值以及各色素组分的相关性均未达到显著水平,a值与色素总量和色素组分的相关性比b值密切;柿果色泽主要是由5种类胡萝卜素组分共同积累所致,其中隐黄质和β-胡萝卜素对其起着关键作用;黄色玻璃纸处理有利于柿果色泽形成和色素合成,红光和弱光不利于柿果色素合成,其中对"红色系"色素积累影响较大。 展开更多
关键词 '富有' 色泽形成 色素积累 套袋 类胡萝卜素
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不同套袋处理对甜柿果实品质的影响 被引量:15
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作者 胡青素 谭晓风 龚榜初 《林业科学研究》 CSCD 北大核心 2010年第2期209-214,共6页
为探讨套袋对甜柿果实品质的影响,采用9种果袋,于7月10日统一对‘富有’甜柿果实进行套袋试验,10月7日去袋,至11月7日果实成熟时统一采摘。研究结果表明:采前30 d去袋的套袋处理利于甜柿果实着色,双层袋处理5使果实呈典型的橙黄色。果... 为探讨套袋对甜柿果实品质的影响,采用9种果袋,于7月10日统一对‘富有’甜柿果实进行套袋试验,10月7日去袋,至11月7日果实成熟时统一采摘。研究结果表明:采前30 d去袋的套袋处理利于甜柿果实着色,双层袋处理5使果实呈典型的橙黄色。果皮中色素与色泽呈显著相关性。单层袋处理7极显著降低了果面锈斑率及病褐斑发生率。套袋降低了甜柿果实内可溶性固形物和还原糖含量,以双层袋的降低效应较为明显。单层袋及双层袋处理6显著提高了果实内可溶性总糖和维生素C含量。各果袋均利于提高甜柿果实内游离氨基酸和蛋白质含量,单层袋处理7使果实内蛋白质的含量达到6.1×10-3mg.g-1,达到显著差异水平。双层袋处理6除对Zn的含量有降低外,均明显提高其它各类矿质元素的含量。综合考虑各项指标得出,白色复合纸单层袋最适于提高甜柿果实的内外品质,外黄内白双层袋次之。 展开更多
关键词 套袋 '富有’甜柿 色素 色泽 内外品质
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Ecological Geochemistry of Selenium in the Production Base of Zhangqiu Green Chinese Onion 被引量:3
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作者 庞绪贵 高宗军 +1 位作者 王敏 王增辉 《Agricultural Science & Technology》 CAS 2010年第11期39-43,共5页
Based on the achievement of local ecological geochemical survey,the selenium in surface layer soil of Zhangqiu green Chinese onion within production area is systematically studied in this study.And the ecological geoc... Based on the achievement of local ecological geochemical survey,the selenium in surface layer soil of Zhangqiu green Chinese onion within production area is systematically studied in this study.And the ecological geochemical characters of selenium both in surface layer soil and in green Chinese onions are analyzed,and the relationship between the selenium in plant and soil is discussed.The results show that soil in Zhangqiu is rich in selenium,and it is suitable to develop the selenium-rich green Chinese onion products. 展开更多
关键词 Ecological geochemistry Zhangqiu green Chinese onion Selenium-rich agricultural products Available selenium Biological accumulation coefficient
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Simulation of Cobalt-Rich Crust’s Crushing Process Based on ANSYS 被引量:2
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作者 XIA Yi-min MA Zhi-guo BU Ying-yong ZHAO Hai-ming 《Journal of China University of Mining and Technology》 EI 2006年第1期28-32,共5页
It is a great concern in international oceanology to mine cobalt-rich crust. At present, spiral mining head is regarded as the best crushing scheme. Based on the dynamic model of spiral mining head, the of cobalt crus... It is a great concern in international oceanology to mine cobalt-rich crust. At present, spiral mining head is regarded as the best crushing scheme. Based on the dynamic model of spiral mining head, the of cobalt crust’s crushing process was simulated with the ANSYS software. The material model of Johnson and Cook Plasticity, maximal princi- pal stress failure criterion, and eroding contact arithmetic were selected. At the same time, the influence of cutting depth, feed speed, rotational speed of mining head on torque and force subjected by mining head was taken into account. At last a computer simulation model of crushing process of cobalt crust was established. By analyzing simulation results, the relationships among these controllable process parameters, torque and force can be obtained, which will provide a technical reference for practical mining system. 展开更多
关键词 cobalt-rich crust mining head SIMULATION finite element ANSYS
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Forest Biodiversity Assessment in Peruvian Andean Montane Cloud Forest 被引量:5
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作者 Alicia Ledo Sonia Condés Iciar Alberdi 《Journal of Mountain Science》 SCIE CSCD 2012年第3期372-384,共13页
Cloud forests are unusual and fragile habitats, being one of the least studied and least understood ecosystems. The tropical Andean dominion is considered one of the most significant places in the world as regards bio... Cloud forests are unusual and fragile habitats, being one of the least studied and least understood ecosystems. The tropical Andean dominion is considered one of the most significant places in the world as regards biological diversity, with a very high level of endemism. The biodiversity was analysed in an isolated remnant area of a tropical montane cloud forest known as the "Bosque de Neblina de Cuyas", in the North of the Peruvian Andean range. Composition, structure and dead wood were measured or estimated. The values obtained were compared with other cloud forests. The study revealed a high level of forest biodiversity, although the level of biodiversity differs from one area to another: in the inner areas, where human pressure is almost inexistent, the biodiversity values increase. The high species richness and the low dominance among species bear testimony to this montane cloud forest as a real enclave of biodiversity. 展开更多
关键词 Andean Range BIODIVERSITY Dead wood Montane forest Species composition Stand structure Tropical forest
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The enrichments of organic matter and total nitrogen in sediment as affected by relavant factors
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作者 张兴昌 郑纪勇 李世清 《Journal of Geographical Sciences》 SCIE CSCD 2004年第4期495-502,共8页
Serious soil erosion has already resulted in degradation of the Loess Plateau of China. Soil erosion is commonly accompanied by extensive soil nutrient loss. Because of enrichment processes,sediment nutrient content i... Serious soil erosion has already resulted in degradation of the Loess Plateau of China. Soil erosion is commonly accompanied by extensive soil nutrient loss. Because of enrichment processes,sediment nutrient content is often higher than that of natural soil. The objective of this study is to determine the enrichments of organic matter and total nitrogen in sediment in hilly and gully loess areas on the Loess Plateau of China. Measurements of enrichment ratios (ER) of organic matter (EROM) and total nitrogen (ERTN) in sediment as affected by rainfall, slope gradient, tillage, and fertilization were made in the field under natural rainfall conditions. The results showed that the enrichment of clay in sediment resulted in the enrichment of organic matter (OM) and total nitrogen (TN) in sediment. The averages of sediment clay ER, EROM and ERTN for the various slope gradients were 1.77, 2.09 and 1.61, respectively. The soil erosive module was negatively correlated with EROM and ERTN. Our results indicate that measures to reduce soil erosion, i.e. reducing rainfall erosivity, decreasing soil slope gradient, decreasing fertilizer use, and using level trenches, may increase EROM and ERTN. Both quantity and quality of sediment yield should be considered when implementing erosion control measures. 展开更多
关键词 SEDIMENT organic matter total nitrogen enrichment ratio
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Harmful algal blooms and eutrophication: "strategies" for nutrient uptake and growth outside the Redfield comfort zone 被引量:22
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作者 Patricia M. GLIBERT JoAnn M. BURKHOLDER 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第4期724-738,共15页
While many harmful algal blooms have been associated with increasing eutrophication, not all species respond similarly and the increasing challenge, especially for resource managers, is to determine which blooms are r... While many harmful algal blooms have been associated with increasing eutrophication, not all species respond similarly and the increasing challenge, especially for resource managers, is to determine which blooms are related to eutrophication and to understand why particular species proliferate under specific nutrient conditions. The overall goal of this brief review is to describe why nutrient loads are not changing in stoichiometric proportion to the "Redfield ratio", and why this has important consequences for algal growth. Many types of harmful algae appear to be able to thrive, and/or increase their production of toxins, when nutrient loads are not in proportion classically identified as Redfield ratios. Here we also describe some of the physiological mechanisms of different species to take up nutrients and to thrive under conditions of nutrient imbalance. 展开更多
关键词 HABS MIXOTROPHY nitrogen nutrient loading nutrient ratios nutrient stoichiometry organicnutrients PHOSPHORUS
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Sedimentary facies characteristics and organic matter enrichment mechanism of lower Cambrian Niutitang Formation in South China 被引量:1
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作者 QIN Ming-yang GUO Jian-hua +2 位作者 TAN Hui WU Shi-qing BIAN Rui-kang 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第12期3779-3792,共14页
The purpose of this study was to examine the sedimentary facies characteristics of lower Cambrian Niutitang Formation(∈1n)in South China,to reveal the mechanism of organic matter enrichment,and to guide exploration o... The purpose of this study was to examine the sedimentary facies characteristics of lower Cambrian Niutitang Formation(∈1n)in South China,to reveal the mechanism of organic matter enrichment,and to guide exploration of shale gas.Macro investigation and experimental analyses were used to assess the lithology in detail,total organic matter mass fraction w(TOC),mineral composition,and trace element characteristics of∈1n.The influencing factors of organic matter enrichment were discussed extensively,and a sedimentary facies mode was suggested.In the early stage of∈1n,the locations of Well E’yangye 1,Well Ciye 1,Well Changye 1,and Well Anye 1 respectively develop,platform inner sag,outer shelf,Jiangnan slope belt,and South China detention basin.In the late stage of∈1n,the sedimentary facies evolve with decreasing sea level.The study area presents a complete three-step basin in the Early Cambrian.In the early stage of∈1n,the first step is the Yangtze carbonate platform,the second step is the outer shelf and slope,and the third step is the deep-water basin.From the Yangtze carbonate platform to the deep-water basin,w(TOC)and the mass fraction of quartz gradually increase,the mass fraction of carbonate mineral decreases,and the mass fraction of clay mineral is higher in the second step.The sea level fluctuation results in a higher w(TOC)vertically in the lower∈1n shale,and the paleogeographic(provenance)conditions lead to better horizontal development of organic matter in the outer shelf,slope and detention basin.Trace elements are abundant in the lower∈1n,and w(TOC)is correlated positively with many trace elements.In the outer shelf,slope,and adjacent areas,hydrothermal activity and upwelling current bring nutrient-rich material and promote organic matter enrichment under a strong reducing condition.Deep-shelf,slope and deep-water basin are the best facies for the formation and preservation of organic matter,especially deep-water basin facies.It remains necessary to strengthen the exploration of shale gas in the deep-water basin of∈1n in central Hunan,China. 展开更多
关键词 Niutitang formation(∈1n) organic matter sedimentary facies enrichment mechanism hydrothermal activity upwelling current exploration target
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Are typhoon and marine eutrophication the possible missing sources of high dissolved organic nitrogen in wet deposition?
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作者 CHANG Ming CHEN Weihua +2 位作者 DENG Sixin WANG Xuemei ZHOU Shengzhen 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第3期182-187,共6页
The aim of this study is to elaborate a possible missing source of high-throughput organic nitrogen in rainfall.The authors classified the observed flux data of dissolved organic nitrogen in terms of the attributes of... The aim of this study is to elaborate a possible missing source of high-throughput organic nitrogen in rainfall.The authors classified the observed flux data of dissolved organic nitrogen in terms of the attributes of the wet deposition event itself,such as the season,precipitation,air mass backward trajectory,and effect of typhoons.The monitoring results of the ocean eutrophication and the chlorophyll-a map of the surface water were compared with the trajectory of the high-flux deposition events.The results show that approximately one third of the total wet deposition organic nitrogen derived from a confluence of three factors:rain in the wet season,air masses from the ocean,and rainfall over 50 mm.It could be seen that the co-occurrence of intense events such as a typhoon and eutrophic surface sea waters might be an important source of dissolved organic nitrogen in wet deposition. 展开更多
关键词 Organic nitrogen deposition marine eutrophication TYPHOON
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Depth distribution and ecological preferences of periphytic algae in Kenyir Lake,the largest tropical reservoir of Malaysia 被引量:1
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作者 ROUF A.J.M.Abdur PHANG Siew-Moi AMBAK M.Azmi 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第4期856-867,共12页
We studied the depth distribution of periphyton,growing on inundated dead trees in Kenyir Lake,Malaysia in June 1995.The algal floral composition and structure manifested changes down the depth gradient in terms of sp... We studied the depth distribution of periphyton,growing on inundated dead trees in Kenyir Lake,Malaysia in June 1995.The algal floral composition and structure manifested changes down the depth gradient in terms of species richness,abundance,diversity and cell density.In regression analysis,all these algal attributes were negatively correlated with the depth gradients at P<0.05.In terms of species richness,the bacillariophytes showed dominance over the cyanophytes and chlorophytes;whereas with respect to standing crop,the cyanophytes showed dominance over the bacillariophytes and chlorophytes.The chlorophyll a was higher at the mid and bottom-depths than the surface-depth in both the downstream and upstream sites,which showed that vertical productivity or biomass accumulation was greater in low light irradiance.The product-moment correlation analysis showed that conductivity,turbidity,dissolved oxygen,reactive phosphate and ammonium-nitrogen were highly correlated with the algal assemblage data.However,photosynthetic active radiation(PAR) showed poor correlation with the community data.These observations have cast some light on the autoecological characteristics,habitat preferences and environmental responses of tropical periphytic communities. 展开更多
关键词 depth periphytic algae TROPICAL large reservoir Kenyir Lake community structure biomass
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Inorganic Carbon Parameters Responding to Summer Hypoxia Outside the Changjiang Estuary and the Related Implications 被引量:6
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作者 WANG Bin CHEN Jianfang +2 位作者 JIN Haiyan LI Hongliang XU Jie 《Journal of Ocean University of China》 SCIE CAS 2013年第4期568-576,共9页
The eutrophication, hypoxia and coastal acidification are attracting more and more attention. In this study, inorganic carbon parameters, including dissolved inorganic carbon (DIC), total alkalinity (TA) and calcu... The eutrophication, hypoxia and coastal acidification are attracting more and more attention. In this study, inorganic carbon parameters, including dissolved inorganic carbon (DIC), total alkalinity (TA) and calculated partial pressure of CO2 (pCO2), obtained from a summer cruise in August, 2009, were used to investigate their integrated response to biological processes accompanying the oxygen depletion in the areas off the Changjiang Estuary. According to the observations, the typical hypoxia occurred in the bottom water just outside the Changjiang Estuary with Dissolved Oxygen (DO) lower than 2.00 mg L^-1. The biological uptake in the surface water and the decomposition of organic matter in the bottom water were fully coupled with each other. The high concentration of Chl_a (Chl_a = 10.9μgL^-1) and DO (9.25 mgL^-1), profoundly decreased DIC concentration 0828 μmolkg^-1) and elevated pH (8.42) was observed in the surface water. The correspondingly increased DIC and depletion of oxygen were observed in the bottom water. The semi-quantitative analysis proved that the locally-produced phytoplankton, determined by primary productivity, was deposited to the bottom and contributed about 76% of total amount of the organic carbon decomposition in the bottom. However, in the bottom hypoxia (DO = 2.05 mgL^-1) area observed in the Southern Zhejiang coastal water, the responding patterns of inorganic carbon parameters deviated from the previous one. The expanding of Changjiang Diluted Water (CDW), the adding of Hangzhou Bay water (with high DIC concentration) and Coastal Current together modify the DIC background value in this area, and the local degeneration and upwelling process may also help to offset the local DIC removed by net biological uptake in surface water. In addition when the mixing occurring in autumn, which may break the summer stratification, the excess release of high DIC in the bottom water to the subsurface water could have an important influence on coastal acidification and the CO2 uptake capacity in this area. 展开更多
关键词 dissolved inorganic carbon (DIC) biological uptake HYPOXIA coastal acidification
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Are Polymers Toxic? Case Study: Environmental Impact of a Biopolymer
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作者 Giovanna Mercado Martha Dominguez +1 位作者 Israel Herrera Rosa Maria Melgoza 《Journal of Environmental Science and Engineering(B)》 2017年第3期121-126,共6页
In this paper, the analysis of the environmental impacts of a biopolymer based on starch is presented. These impacts were calculated from a cradle to gate LCA (Life Cycle Assessment), based on UNEEN ISO 14040:2006 ... In this paper, the analysis of the environmental impacts of a biopolymer based on starch is presented. These impacts were calculated from a cradle to gate LCA (Life Cycle Assessment), based on UNEEN ISO 14040:2006 and UNEEN ISO 14044, using as functional unit 1 kg of produced biomaterial. The impact categories analyzed were global wanning, ozone depletion, acidification and eutrophication. The results indicate that the electricity causes the highest impacts in the global warming and ozone depletion categories, but compared to synthetic polymers, the emissions are low. Finally, in the case of eutrophication, the impacts are similar to other biopolymers but higher in comparison with petroleum-based polymers like HDPE (High Density Polyethylene), LDPE (Low Density Polyethylene), PP (Polypropylene), PS (Polystyrene) and PET (Polyethylene Terephthalate). 展开更多
关键词 Polymer BIOPOLYMER LCA environmental impacts.
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Diversity, Endemism and Conservation of Ferns(Polypodiales) in the Mexican Mountain Component 被引量:2
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作者 SANGINéS-FRANCO Celia LUNA-VEGA Isolda +3 位作者 CONTRERAS-MEDINA Raúl ESPINOSA David TEJERO-DíEZ José Daniel RIVAS Gerardo 《Journal of Mountain Science》 SCIE CSCD 2015年第4期891-904,共14页
We analyzed the distributional patterns of95 selected species of leptosporangiate ferns inhabiting the Mexican Mountain Component, using grid-cells of one geographical degree as unit areas,applying endemism indices an... We analyzed the distributional patterns of95 selected species of leptosporangiate ferns inhabiting the Mexican Mountain Component, using grid-cells of one geographical degree as unit areas,applying endemism indices and richness and beta diversity analyses.Distributional data were obtained from several herbaria and specialized literature.Five grid-cells appear to be important for fern species richness, as they contain 35 to 49 species.These gridcells are located in the Sierra Madre Oriental(SMO),Trans-Mexican Volcanic Belt(TMVB) and the Sierra Madre del Sur(SMS).Mean richness by latitudinal belts of one degree showed that the belts with highest values are related to the TMVB and SMS.A total of 13grid-cells were recognized as important from theperspective of endemism; most of them are located also in the SMO, TMVB and SMS.The richest gridcells coincided with one of the main centres of endemism for ferns obtained in this study, located in the convergence of the southern part of the SMO, the eastern portion of the TMVB and the northern part of the SMS, reflecting the high humidity existing on the mountain slopes facing the Gulf of Mexico.Some important grid-cells recognized from richness and endemism analyses coincide with Mexican Natural Protected Areas.The beta diversity analysis showed a low degree of similarity among grid-cells, implying a high species replacement, as the result of environmental heterogeneity occurring in the Mexican mountain systems.On the other hand, the spatial analysis suggested a pattern of phytogeographical regionalization comprising twomain areas: the Mexican Transition Zone and the Mexican Central Plateau.Ferns play an important role in the Mexican biodiversity and contributing to the beta diversity of Mexico. 展开更多
关键词 BIOGEOGRAPHY Distributional patterns Leptosporangiate ferns Mexico
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Spacial Distribution Characteristics, Activity and Degradation Capability of the Biofilm in Integrated Vertical-flow Constructed Wetland 被引量:1
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作者 J. Li X.X. Mao Z.B. Wu 《Journal of Environmental Science and Engineering》 2010年第10期57-62,共6页
The spacial distribution characteristics, activity and degradation capability of the biofilm in integrated vertical-flow constructed wetland were investigated. Results showed that the biofilm widely distributed in the... The spacial distribution characteristics, activity and degradation capability of the biofilm in integrated vertical-flow constructed wetland were investigated. Results showed that the biofilm widely distributed in the substrate of integrated vertical-flow constructed wetland and mainly in the 0-10 cm top layer where the activity ofdehydrogenase of the biofilm was also higher than that of other layers. The water quality could also affect the activity of the biofilm, for the TF(1,3,5-Triphenylformazan) amount reduced by the biofim incubated in water of the higher eutrophication was larger, too. The PCP (pentachlorophenol) removal rate by the substrate with biofilm was 1.5 times that without biofilm. In total, the biofilm of the down-flow chamber appeared larger biomass, higher dehydrogenase activity and stronger degradation capability of organic contamination than that in up-flow chamber and it was the major place for removal of the organic matters in waste water. 展开更多
关键词 Integrated vertical-flow constructed wetland BIOFILM DISTRIBUTION activity of dehydrogenase degradation capacity
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Characterization of NOM and THM formation potential in eutrophic reservoir water
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作者 张兵 刘志生 +2 位作者 周璇 刘莉 崔福义 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第3期322-325,共4页
Resin adsorption technique with XAD-8 and XAD-4 was used to characterize the raw water from Erlong reservoir in Jilin province of China. The NOM chemical composition sequences of four organic fractions in the raw wate... Resin adsorption technique with XAD-8 and XAD-4 was used to characterize the raw water from Erlong reservoir in Jilin province of China. The NOM chemical composition sequences of four organic fractions in the raw water, from high to low, are fulvic acid (FA) fraction, hydrophilic non-acid (HPINA) fraction, hydrophilic acid (HPIA) fraction, and humic acid (HA) fraction. Experimental results show that FA is the main precursor of THMFP among the four organic fractions. However, HA or hydrophobie acid exhibits the highest chlorination activity in forming THMs. It is also found that the value of FI/DOC or SUVA and the specific THMFP have better positive correlation. It is implied that certain source water has unique nature of NOM and DBPs. 展开更多
关键词 natural organic matter (NOM) disinfection by-products trihalomethane formation potential (THMFP) chlorination activity FRACTION
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C-Nanostructures Cluster Models in Organic Solvents: Fullerenes, Tubes, Buds and Graphenes
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作者 Francisco Torrens Gloria Castellano 《Journal of Chemistry and Chemical Engineering》 2013年第11期1026-1035,共10页
The existence of nanographene in cluster form is discussed in organic solvents. Theories are developed based on the columnlet, bundlet and droplet models describing the size-distribution functions. Phenomena present a... The existence of nanographene in cluster form is discussed in organic solvents. Theories are developed based on the columnlet, bundlet and droplet models describing the size-distribution functions. Phenomena present a unified explanation in the columnlet model in which free energy of Cgraphene involved in cluster is combined from a volume part proportional to the number of molecules n in cluster and a constant. The columnlet model enables describing distribution function of Cgraphene clusters by size. From purely geometrical considerations the columnlet (Cgraphene), bundlet (single-wall carbon nanotube), CNT (carbon nanotube), SWNT (single-wall C-nanotube), and carbon nanobud, CNB (carbon nanobud)) and droplet (fullerene) models predict dissimilar behaviours. The interaction-energy parameters of Cgraphene are taken from C60. An CNB behaviour or further is expected. The decay of solubility with rising temperature is smaller for Cgraphene than for SWNT and CNB and, furthermore, than for C60, in agreement with lesser numbers of units in Cgraphene clusters. The discrepancy between the experimental data of the heat of solution of fullerenes, CNTs, CNBs and graphenes is ascribed to the sharp concentration dependence of the heat of solution. The diffusion coefficient drops with temperature result greater for Cgraphene than CNB and SWNT than C60 corresponding to lesser number of units in clusters. The aggregates near (C60)13, SWNT/CNB7 and (Cgraphene)3 could be representative of the droplet, bundlet and columnlet models. 展开更多
关键词 NANOSTRUCTURE graphene solubility columnlet cluster model bundlet cluster model droplet cluster model nanobud.
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