饵料对稚幼参生长变色的影响

报告了藻粉,浮泥,人工配合饵料,混合饵料对稚幼长岛县牝一海水育苗场变色的影响。经３个胸月的投喂试验。结果：人工配合饵料组稚幼参体长,体重增长较快,纯藻粉组,浮泥组投喂效果都较差。藻粉中添加部分“海丰”牌饲料预混剂和３０％的浮泥,对稚参有明显的助长作用,日均增长,增重是纯藻粉组的２倍以上,且明显快于人工配合饵料组。     

藻类在猪和鸡养殖生产中的应用研究进展

文章总结了畜禽生产中可利用的藻类及其营养成分,重点介绍了含藻饲料对以猪和鸡为代表的畜禽生长、免疫、肌肉品质、产蛋性能和禽蛋品质等方面的影响,还指出了藻类在畜禽饲料应用中存在的问题并提出建议,旨在为藻类资源在猪、鸡养殖生产中的广泛应用提供参考。藻类分布广、易生长、产量大,尤其是海藻,含有陆生植物不具有的生物活性物质和营养物质。将富含不饱和脂肪酸和色素的微藻添加到饲料中能改善畜禽肉品质,提升禽蛋品质;将富含多糖等活性物质的大型海藻添加到饲料中有助于提升畜禽免疫力。饲料中添加少量藻类可提高饲料稳定性,提升畜禽生长性能和饲料利用率;当藻类添加量过高时,其所含的抗营养因子会对畜禽产生负面影响,但通过适当的预处理可消除部分抗营养因子,减轻负面效应。     

Intercalation of the herbicide atrazine in layered double hydroxides for controlled-release applications

BACKGROUND: The herbicide atrazine was intercalated in the interlayer region of Mg/Al layered double hydroxides in order to produce a nanohybrid that could be used in controlled‐release applications. RESULTS: The hydrophobic herbicide was incorporated in artificial membranes formed in the interlayer of the inorganic host by using palmitic acid. The synthetic nanohybrid material was characterised by various techniques, and release studies were carried out. In addition, the photosynthetic alga Chlamydomonas reinhardtii Dang. was treated with the atrazine‐containing nanohybrid, which exerted an herbicidal efficacy similar to that of the free herbicide. CONCLUSION: The herbicide containing nanohybrid could enable a controlled release of the herbicide. In addition, the herbicide would be delivered close to its site of uptake, enhancing efficiency and reducing the required doses. Copyright © 2011 Society of Chemical Industry     

酵母及藻类对褶皱臂尾轮虫培养效果的比较研究

采用种群累积培养法研究了两种酵母、两种藻类对褶皱臂尾轮虫的最适投喂密度。结果表明 ,这四种饵料对褶皱臂尾轮虫的最适投喂密度 (× 10 6cell·ml-1)分别是 :干酵母 ,15 ;鲜酵母 ,5 ;微绿球藻 ,4 5 ;三角褐指藻 ,2 0。同时 ,在最适密度下比较了这四种饵料对轮虫的培养效果。结果表明 ,四种饵料对轮虫的培养效果以微绿球藻为最优 ,其它依次为三角褐指藻 ,鲜酵母 ,干酵母。实验结果显示 ,褶皱臂尾轮虫批量培养及至工厂化培养的首选饵料是微绿球藻和三角褐指藻     

Effect of dietary defatted diatom biomass on egg production and quality of laying hens

Background： This study was to determine if feeding laying hens with defatted diatom microalgal biomass （DFA） from biofuel production affected their egg production and health status. Methods： Five replicates of 5 individually caged ISA Babcock White leghorn hens were fed 4 diets, including a corn-soybean meal control diet, a diet containing 7.5% DFA substituting for soybean meal, and diets containing 7.5% or 15% DFA substituting for corn and soybean meal. Body weights, feed intake, feed conversion ratio （FCR）, rate of egg production, egg size, egg mass, and several characteristics of eggs were determined at 4 and 8 wk. Venous blood was sampled at 4 and 8 wk for measurement of 5 biomarkers of health. Results： The15% DFA diet decreased （P 〈 0.05） feed intake, egg production, and plasma uric acid concentrations as compared with the control diet, but increased （P 〈 0.05） egg albumen weight and height compared with the 7.5% DFA diets. The two levels of DFA produced dose-dependent （P 〈 0.05） changes in three color measures of egg yolk, without affecting four hen plasma biochemical indicators of health. Conclusions： Feeding laying hens with 7.5% DFA in the corn-soybean meal diet for 8 wk had no adverse effect on their health, egg production, or egg quality, but 15% inclusion reduced feed intake, egg production, and efficiency of feed utilization.     

Distribution of free oxides along soil profiles in time series of dry rice fields in polder lands of Kojima-basin

The distributions of free oxides along profiles of some dry rice fields were set forth in the previous reports²,³,⁴,⁶⁾, In this paper, the distribution of free oxides in dry rice field⁵⁾ in polder lands of Kojima-Basin, Okayama pref. is reported. Localities, years elapsed since the planting of rice began in each field and the characteristic of soil profiles are given in Table 1. All the fields are dry rice fields except Soil A, and carry barley or wheat in winter season. Parent materials are similar in all horizons of all soils and rich in fine particles. Fine sands (0.2-0.02 mm) are mainly composed of quartz somewhat accompanied with feldspars, mica, augite and amphibolite. Clays (< 0.002 mm) are mainly composed of halloysite accompanied with a small proportion of montmorillonite. The structure develops well in all the soils.     

海藻热解生物油的成分分析

为了明确海藻热解生物油的主要成分及热解工况对成分的影响,对海藻生物质（条浒苔、马尾藻）不同工况下热解制得的生物油进行气相色谱质谱联用分析。海藻类生物油成分除了含氮化合物外,主要是一些烃类、酮类、醛类、醇类和酚类化合物,以及较大分子量的羧酸及其衍生物,并包含了少量呋喃、吡喃、吡啶等衍生物的杂环化合物。条浒苔油中羧酸及其衍生物（37.85%）和烃类物质（16.61%）较多,而马尾藻生物油中甾族（30.16%）和醇类化合物（24.81%）较多,也检测出油酸、棕榈酸酯和花生酸。不同工况下产生的生物油在组成成分上非常相似,只是相对含量有所不同。热解温度对海藻油组分分布起了重要作用,而载气流量对热解海藻油组分分布的影响不明显。试验结果还表明海藻油中含氮化合物的形成主要与蛋白质的分解有关。海藻生物油相对于陆上植物热解生物油优点为高含烃量,低含氧量。海藻热解制油工艺中温度应控制在500～600℃之间,能达到较佳产油率和油品。     

稻田中藻类的生长状况及其对肥料氮的固持

为了确定藻类对稻田生态系统中氮素固持与迁移过程的影响程度,本研究采用田间小区和15N微区试验,在水稻生长的不同时期,观测了藻类在稻田中的生长状况,定量测定了藻类的生物量和氮素固持量.结果显示,稻田中的藻类具有明显的群落演替特征,水稻生育初期以球状藻为主,中后期则以丝状藻为主.藻类的生长可分为两个阶段,即生长期和衰亡期,其中,生长期从稻秧移栽初期至拔节期,衰亡期从拔节期至水稻收获.在衰亡期,藻类生物量随时间的变化符合生长曲线模式.藻类生物质干重在2007和2009年水稻生育期的变化范围分别为205～610 kg/hm2和12～353 kg/hm2,而藻类氮素固持量则分别为N 5.4～17.5 kg/hm2和N0.4～11.0 kg/hm2.15N微区试验结果显示,藻类对15N的固持量为N 0.3～6.0 kg/hm2,占氮素总固持量的54％～68％,平均为57％,表明藻类固持的氮素中大部分来源于当季施入的氮肥.     

Photosynthetic pigments in soils from northern Victoria Land (continental Antarctica) as proxies for soil algal community structure and function

Although soil algae are among the main primary producers in most terrestrial ecosystems of continental Antarctica, there are very few quantitative studies on their relative proportion in the main algal groups and on how their distribution is affected by biotic and abiotic factors. Such knowledge is essential for understanding the functioning of Antarctic terrestrial ecosystems. We therefore analyzed biological soil crusts from northern Victoria Land to determine their pH, electrical conductivity (EC), water content (W), total and organic C (TC and TOC) and total N (TN) contents, and the presence and abundance of photosynthetic pigments. In particular, the latter were tested as proxies for biomass and coarse-resolution community structure. Soil samples were collected from five sites with known soil algal communities and the distribution of pigments was shown to reflect differences in the relative proportions of Chlorophyta, Cyanophyta and Bacillariophyta in these sites. Multivariate and univariate models strongly indicated that almost all soil variables (EC, W, TOC and TN) were important environmental correlates of pigment distribution. However, a significant amount of variation is independent of these soil variables and may be ascribed to local variability such as changes in microclimate at varying spatial and temporal scales. There are at least five possible sources of local variation: pigment preservation, temporal variations in water availability, temporal and spatial interactions among environmental and biological components, the local-scale patchiness of organism distribution, and biotic interactions.