Comments on soil memory and paleo-environmental reconstruction of soil evolution     

Dan Yaalon 《Eurasian Soil Science》2011,44(4):462-463

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Functional porous carbons from waste cotton fabrics for dyeing wastewater purification     

Shuhua Wang  Meixia Wei  Qiaoli Xu  Husheng Jia 《Fibers and Polymers》2016,17(2):212-219

A new functional porous carbons (PC-WF) is prepared by activation-pyrolysis method use waste cotton fabrics (WF) as an abundant, cheap and available precursor for removal of Brilliant Crocein (BC-GR) and Cationic Red 2GL (CR-GL) from aqueous phase. The PC-WF was characterized by BET, FTIR, SEM, and XRD techniques, the surface area, total pore volume, average pore diameter was found as 1463.5 m² g^-1, 0.783 cm³ g^-1 and 2.14 nm, respectively. The influences on BC-GR and CR-GL adsorption of various experimental factors such as initial concentration and temperature were investigated. Adsorption kinetics was found to be best represented by the pseudo-second order model. The adsorption capacity was 319.8 mg g^-1 for BC-GR and 842.5 mg g^-1 for CR-GL at 30 °C, respectively. The results indicate that for waste cotton fabrics in particular, the practical application of this process to the production of porous carbon would be possible.  相似文献   

添加复合酶对临武鸭瓜尔豆胚芽养分、氨基酸和能量利用率的影响     

张旭  李闯  黄璇  何平  王向荣  蒋桂韬  戴求仲 《动物营养学报》2015,(4)

本试验旨在研究添加复合酶对临武鸭瓜尔豆胚芽养分、氨基酸和能量利用率的影响。试验选用24只体重2.0 kg左右的健康成年临武鸭公鸭,随机分为3组,每组8个重复,每个重复1只鸭。采用绝食强饲-全收粪法进行代谢试验。1、2组试验鸭每只强饲60 g/d饲粮,2组饲粮中添加250 mg/kg的复合酶,3组强饲60 g/d无氮饲粮。测定添加复合酶对临武鸭瓜尔豆胚芽中干物质(DM)、粗蛋白质(CP)、粗脂肪(EE)、粗纤维(CF)和17种氨基酸的表观利用率、真可利用率、表观代谢能(AME)和真代谢能(TME)。结果表明,临武鸭对瓜尔豆胚芽DM、CP、EE、CF和能量的真可利用率分别为67.07%、67.57%、65.52%、82.88%和77.39%,AME和TME分别为11.34和13.31 MJ/kg,17种氨基酸的真可利用率为67.72%~93.70%;添加复合酶使临武鸭的DM、CP、EE、CF和能量的真可利用率分别提高了5.23%、8.02%、5.80%、3.66%和3.31%(P0.05),AME和TME分别提高了3.97%和3.27%(P0.05),17种氨基酸的真可利用率提高了1.73%~11.62%,其中丝氨酸、甘氨酸、亮氨酸、酪氨酸和苯丙氨酸的真可利用率显著提高(P0.05)。由此可知,添加含有蛋白酶和非淀粉多糖酶的复合酶能够提高临武鸭对瓜尔豆胚芽中养分、氨基酸和能量的利用率。  相似文献   

Pasteur’s quadrant: an appealing <Emphasis Type="Italic">ecophronetic</Emphasis> alternative to the prevalent Bohr’s quadrant in ecosystem services research     

Wei-Ning Xiang 《Landscape Ecology》2017,32(12):2241-2247

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Kristina Roesel and Delia Grace (eds): Food safety and informal markets: animal products in sub-Saharan Africa     

Ann Waters-Bayer 《Agriculture and Human Values》2016,33(2):493-494

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G.M. Turchini,W.-K. Ng and D.R. Tocher (eds): Fish oil replacement and alternative lipid sources in aquaculture feeds     

Malcolm Jobling 《Aquaculture International》2011,19(3):595-596

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玉米茎秆抗倒伏遗传的研究进展   总被引：2，自引：0，他引：2  

王夏青  宋伟  张如养  陈怡凝  孙轩  赵久然 《中国农业科学》2021,54(11):2261-2272

茎秆倒伏严重影响玉米产量、品质和机械化收获,是当前玉米生产和育种亟待解决的主要问题之一。加强对玉米茎秆抗倒伏性的研究,对提高品种抗倒伏能力具有重要意义。本文综述了玉米茎秆倒伏的主要影响因素及其遗传特征。茎秆倒伏与茎秆自身的强度密切相关。茎秆强度越高,抗倒伏性越强。茎秆强度受茎秆所处的发育阶段、茎秆内部结构和外部形态,及其细胞壁成分等影响。处于分生组织的茎秆细胞分裂旺盛,较易折断,而进入生殖生长后,茎秆表皮、厚壁组织增厚,维管束发育成熟,对茎秆的支撑作用增强。茎秆细胞壁的主要成分——纤维素、半纤维素、木质素、可溶性糖、无机物等均可提升茎秆强度。目前,研究者借助高通量表型平台,利用玉米连锁群体和自交系群体,采用各种定位方法,鉴定到一系列影响茎秆形态、强度、细胞壁成分的相关QTL和候选基因。研究表明,基于单倍型的QTL定位方法比基于单个SNP的定位效果好。一致性QTL分析将不同遗传群体的研究整合到一起,能够提高QTL结果的通用性。茎秆强度的遗传基础复杂,受微效多基因控制,位点间具有加性效应。茎秆成分QTL中的候选基因涉及细胞壁代谢、转录因子、蛋白激酶等。MAIZEWALL是玉米细胞壁相关基因的重要数据库。目前该数据库包含1 156个玉米细胞壁生物学相关的候选基因,为该领域的深入研究提供强大的资源。已鉴定到一系列影响玉米茎秆细胞壁成分、茎秆形态和强度的基因,其功能涉及纤维素合成路径,如纤维素合成酶类、Cobra类、糖基转移酶和核糖转运蛋白类;苯丙烷路径基因,如控制bm1—bm5的相关基因;植物激素类,如赤霉素、生长素、油菜素甾醇相关基因;转录因子如NAC、MYB;miRNA（ZmmiR528）以及F-box基因（stiff1）等。今后应积极探索不同发育时期玉米茎秆倒伏的力学机制;广泛发展自然群体或育种群体进行遗传分析;采取多种定位策略,提高抗倒伏相关基因鉴定的功效;针对优良等位基因,开发各类分子标记,加强抗倒伏分子标记辅助选择。本文将为玉米茎秆抗倒伏遗传机制解析及抗倒伏玉米品种的分子育种提供参考。  相似文献   

Characterizing long-term forest disturbance history and its drivers in the Ning-Zhen Mountains,Jiangsu Province of eastern China using yearly Landsat observations (1987–2011)     

Mingshi Li  Chengquan Huang  Wenjuan Shen  Xinyu Ren  Yingying Lv  Jingrui Wang  Zhiliang Zhu 《林业研究》2016,27(6):1329-1341

Forest losses or gains have long been recognized as critical processes modulating the carbon flux between the biosphere and the atmosphere. Timely, accurate and spatially explicit information on forest disturbance and recovery history is required for assessing the effectiveness of existing forest management. The major objectives of our research focused on testing the mapping efficacy of the vegetation change tracker (VCT) model over a forested area in China. We used a new version of VCT algorithm built upon the Landsat time series stacks (LTSS). The LTSS consisted of yearly image acquisitions to map forest disturbance history from 1987 to 2011 over the Ning-Zhen Mountains, Jiangsu Province of east China. The LTSS consisted of TM and ETM+ scenes with different projections due to distinct data sources (Beijing remote sensing ground station and the USGS EROS Center). The validation results of the disturbance year maps showed that most spatial agreement measures ranged from 70 to 86 %, comparable with the VCT accuracies reported for many places in USA. Very low accuracies were identified in 1995 (38.3 %) and 1992 (56.2 %) in the current analysis. These resulted from the insensitivity of the VCT algorithm to detect low intensity disturbances and also from the mis-registration errors of the image pairs. Major forest disturbance types existing in our study area were identified as agricultural expansion (39.8 %), urbanization (24.9 %), forest management practice (19.3 %), and mining (12.8 %). In general, there was a gradual decreasing trend in forest cover throughout this region, caused principally by China’s economic, demographic, environmental and political policies and decisions, as well as some weather events. While VCT has largely been used to assess long term changes and trends in the USA, it has great potential for assessing landscape level change elsewhere throughout the world.  相似文献   

Effect of ammonia and nitrite on vigour,survival rate,moulting rate of the blue swimming crab <Emphasis Type="Italic">Portunus pelagicus</Emphasis> zoea     

Yong Yang Liao  Hong Hu Wang  Zhi Gan Lin 《Aquaculture International》2011,19(2):339-350

The effects of ammonia and nitrite on vigour, survival rate, moulting rate of zoea of blue swimming crab, Portunus pelagicus, were studied. A total of five nitrite-N treatments (26.67, 53.34, 106.68, 213.36, 426.72 mg/l) and a control (no nitrite-N added) were set up for the acute nitrite-N toxicity experiment; a total of five ammonia-N treatments (8.43, 16.86, 33.72, 67.44, 134.88 mg/l) and a control (no ammonia-N added) were set up for the acute ammonia-N toxicity experiment. The results showed that the vigour, survival rate and moulting rate of zoea of the blue swimming crabs exposed to over 53.34 mg/l were significantly different (P < 0.05) from the control group. The zoea LC₅₀ values (mg/l) of nitrite-N were 179.47, 76.56, 66.70, 37.49, 25.01, 25.35, 25.34 mg/l for 24, 36, 48, 60, 72, 84, 96 h, respectively. The vigour, survival rate and moulting rate of zoea of the blue swimming crabs exposed to over 16.86 mg/l were significantly different (P < 0.05) from the control group. The zoea LC₅₀ values (mg/l) of ammonia-N were 51.04, 39.62, 38.72, 24.43, 16.90, 13.42, 11.16 mg/l for 24, 36, 48, 60, 72, 84, 96 h, respectively. The zoeae are highly sensitive to ammonia and nitrite, and the toxicity of ammonia and nitrite on Portunus pelagicus decrease with development of this crab.  相似文献   

Mild Drought Stress‐Induced Changes in Yield,Physiological Processes and Chemical Composition in Festuca,Lolium and Festulolium          下载免费PDF全文

A. Fariaszewska  J. Aper  J. Van Huylenbroeck  J. Baert  J. De Riek  M. Staniak  Ł. Pecio 《Journal of Agronomy and Crop Science》2017,203(2):103-116

The impact of mild drought stress (3 weeks at 40 % field water capacity) on yield, physiological processes, accumulation of proline and phenolic compounds and forage quality parameters in forage grasses was evaluated in pot experiments. During four different growing periods, the effects of water deficit were assessed in nine varieties from five species (Lolium perenne, Lolium multiflorum, Festuca pratensis, Festuca arundinacea and Festulolium braunii). All measured parameters were affected by drought stress in the different cuts. Photosynthesis, transpiration rate, stomatal conductance and dry matter yield were significantly lower in drought stress than under well‐watered conditions in all varieties. Higher water‐use efficiency was only observed during the first and fourth drought period, while this was not the case in the second and third. Mild drought stress significantly increased the content of proline, phenolic acid, flavonoids, water‐soluble carbohydrates and protein. All tested grasses showed also an increase of organic matter digestibility and cell wall digestibility under drought stress conditions.  相似文献