Individual variation in early life-history traits in brown trout

Abstract – We studied the variability of early life history traits in individually raised progeny of brown trout Salmo trutta L. Eggs from two dams were each fertilized with sperm from 10 sires, producing 20 full-sib families. Each individual progeny was followed from fertilization until death without exogenous food. Egg size was positively correlated with a number of life-history traits, especially length and yolk sac volume at hatching and length at death, and these traits were strongly influenced by maternal effects. We found significant additive genetic variance for growth rate, length at death and life span without external food. Thus these early life-history traits may be modulated by natural selection. We found positive phenotypic and genetic correlations between most early life-history traits. However, life span without external food was negatively correlated with growth rate, indicating a genetic trade-off. ^Note     

论苏轼的茶意人生

北宋文学家苏轼宦海沉浮、命运多舛,颠沛流离中留下海量文献。挖掘梳理其茶诗词资源不难发现,苏轼一生与茶为伴,对茶有着独特体悟,以茶安命,是他的生存智慧。他品茶、种茶、斗茶、写茶,表现非凡茶意人生,是中国茶艺术之魂和中国茶文化推动者。     

秸秆热解多联产模式环境影响评价

为定量评价秸秆热解多联产工程的环境影响,借鉴生命周期评价方法,将秸秆热解多联产系统工程建设单元的物质和能量投入及其环境排放纳入系统边界,对年秸秆处理能力1.0×10~4 t的秸秆热解多联产系统的环境影响进行分析评价。结果表明,不考虑产出品的替代减排,该系统生命周期的环境影响综合指数为175.53。其中,工程建设单元、运行单元和产物利用单元的环境影响潜值分别占18.10%、78.75%和3.15%。钢材和PVC管等物料的环境排放合计占建设单元环境排放综合潜值的93.49%,电力消耗排放占运行单元环境排放综合潜值的93.86%。从资源替代角度看,秸秆燃气替代煤炭、秸秆炭和木醋液分别减施化肥和农药情景下,该项目功能单位的环境影响综合指数为-496.86。秸秆热解多联产系统通过资源替代可有效减少环境排放,具有良好的环境减排效应。在未来秸秆热解多联产系统建设过程中,应选择低碳环保的建筑材料,降低运行电耗。     

响应面法优化发酵鹿肉干工艺及其货架期预测

为改善发酵鹿肉干的品质,对鹿肉干进行发酵工艺优化,并建立货架期预测模型。采用单因素和响应面试验设计,以剪切力为评价指标,结合感官评价,进行鹿肉干工艺优化,研究不同贮藏温度下发酵鹿肉干的挥发性盐基氮(TVB-N)和硫代巴比妥酸值(TBARS)的变化,利用阿伦尼乌斯方程建立货架期预测模型。结果表明,发酵鹿肉干的最佳工艺为戊糖片球菌:木糖葡萄球菌:植物乳杆菌体积比2:2:1,发酵剂接种量5%,发酵温度30 ℃,发酵时间45 h。TVB-N和TBARS的活化能Ea分别为36.42、24.95 kJ·mol^-1,指前因子k₀分别为2.17×10⁶、2.44×10⁴。验证结果表明,以TVB-N和TBARS为指标可以对发酵鹿肉干货架期进行准确预测。     

河北省种植业水污染足迹初报

为进一步评估种植业化肥投入引发水污染对应的环境影响,本文利用水足迹理论结合统计数据,采用Recipe生命周期影响评价法对河北省1995—2014年11个地级市的种植业水污染足迹进行研究。结果表明,2014年河北省农作物单位面积施N量和施P量分别比1995年提高了36.3%、52.5%,1995—2014年间秦皇岛的农作物单位面积年均施N量最高(335.4 kg·hm-2),邯郸的农作物单位面积年均施P量最高(119.1 kg·hm-2);比较1995、2004、2014三年各地市的施肥总量,石家庄农作物N肥施用总量三年均列首位,沧州N肥施用总量增幅最大;邯郸农作物P肥施用总量三年均列首位,承德P肥施用总量增幅最大;近20年石家庄的农作物单位面积水污染足迹(wdf)均值最高(2.350 Ml·H2Oe·hm-2),其次是秦皇岛和邯郸,张家口最低,但秦皇岛的wdf年际增长最显著;比较各地市在1995、2004和2014年种植业区域水污染足迹(WDF),各地市的WDF在三年里均呈增加趋势,其中石家庄的WDF三年均值最高,在1995、2004、2014年均处Ⅰ级区,邯郸的WDF均值位于其次,并在2004、2014年升入Ⅰ级区,且2014年邯郸的WDF超过石家庄居全省首位,秦皇岛的WDF增长比例最大,2014年的WDF比1995年增长了77.4%,而石家庄2014年WDF比1995年增长26.7%,在所有地市中其增长比例最小。本研究为河北省分类指导各地市的农业水资源优化及可持续利用提供依据。     

富氢水预处理对小苍兰切花瓶插寿命及其抗氧化系统的影响

瓶插寿命短是小苍兰切花生产中存在的重要问题。本研究采用1%、10%、25%、50%和100%浓度的富氢水(hydrogen-rich water,HRW)溶液对小苍兰切花进行预处理。发现与去离子水预处理的对照相比,1%的HRW预处理,显著延长小苍兰的瓶插寿命,花序和单花的瓶插寿命分别比对照延长了15.99%和7.91%。1%的HRW预处理后,小苍兰切花萎蔫期的丙二醛含量显著低于对照。与对照相比,盛花期和萎蔫期超氧化物歧化酶活性显著增加,萎蔫期过氧化氢酶和抗坏血酸过氧化物酶的活性显著增加。HRW处理后,小苍兰切花可能通过提高细胞的抗氧化能力,从而延长小苍兰切花的瓶插寿命。     

Early life history connectivity of Antarctic silverfish (Pleuragramma antarctica) in the Ross Sea

A recent population hypothesis for Antarctic silverfish (Pleuragramma antarctica), a critical forage species, argued that interactions between life history and circulation associated with glacial trough systems drive circumpolar distributions over the continental shelf. In the Ross Sea, aggregations of eggs and larvae occur under fast ice in Terra Nova Bay, and the hypothesis predicted that dispersing larvae encounter outflow along the western side of Drygalski Trough. The outflow advects larvae towards the shelf‐break, and mixing with trough inflow facilitates return toward the inner shelf. To examine the hypothesis, we compared samples of P. antarctica collected near Coulman Island in the outflow, along Crary Bank in the inflow, and a third set taken over the rest of the Ross Sea. We ruled out misidentification using an innovative genetic validation. Silverfish larvae comprised 99.5% of the catch, and the highest population densities were found in Drygalski Trough. The results provided no evidence to reject the population hypothesis. Abundance indices, back‐calculated hatching dates, length distributions and growth were congruent with a unified early life history in the western Ross Sea, constrained by cryopelagic early stages in Terra Nova Bay. By contrast, a sample in the Bay of Whales revealed much smaller larvae, suggesting either a geographically separate population in the eastern Ross Sea, or westward connectivity with larvae spawned nearby by fish sourced from troughs upstream in the Amundsen Sea. These results illustrate how hypotheses that integrate population structure with life history can provide precise spatial predictions for subsequent testing.     

Distribution patterns of loliginid squid paralarvae in relation to the oceanographic features off the South Brazil Bight (22°–25°S)

Loliginid squids constitute marine resources of increasing importance in shelf ecosystems off the coast of South Brazil. However, the existing information and knowledge about the occurrence of early‐life stages and causes of distributional patterns are insufficient. Here, we have revisited Brazilian historical plankton samples obtained from 11 oceanographic surveys to identify paralarvae and their abundances over time. The study area and time period cover the region between Cabo de São Tomé (22°S) and Cananéia (25°S) at depths down to 200 m from 1991 to 2005. Of the 246 paralarvae quantified, ~50% were identified to the genus or species level, including Doryteuthis spp. (D. sanpaulensis and D. plei), Lolliguncula brevis and a single specimen of Pickfordiateuthis pulchella. Paralarval occurrence and abundance peaked in different areas and were associated with distinct oceanographic conditions: D. sanpaulensis occurred in the northern region associated with cold waters and upwelling events, D. plei occurred primarily in the southern region of the study area and in warmer waters, and L. brevis was found in shallow and low salinity waters in the estuarine region off the coast of Santos. Overall, the highest abundance of paralarvae occurred in the nearshore, northernmost areas during summer, and this can be associated with the observed retention mechanisms caused by local circulation, seasonal upwelling, the intrusion of nutrient‐rich waters, and spawning peaks. The present study provides new information and evidence for loliginid patterns in the area that may potentially be useful for better understanding the recruitment patterns and fishery assessments of squid populations.     

近30年渤海鱼类种群早期补充群体群聚特性和结构更替

基于30余年渤海鱼卵、仔稚鱼历史调查资料的整理分析并结合产卵场补充调查,以1982~1983年周年逐月调查资料为本底,采用多元统计学方法分析30余年渤海鱼类种群早期补充群体群聚特性(物种多样性和关键种群)的季节变化和年代际变化,并掌握结构更替过程中优势种和重要种协同消长规律。分析结果显示,渤海各调查季节(冬季除外)鱼卵、仔稚鱼种类数以及资源丰度指数呈先降后升变动趋势。当前鱼卵种类数仅为20世纪80年代1/2左右,资源丰度不足20世纪80年代的1/10;仔稚鱼种类数和资源丰度仅为20世纪80年代的3/4左右,但冬季仔稚鱼种类数和资源丰度指数呈现上升趋势。各调查时期相同季节鱼卵优势种变化不明显,但仔稚鱼优势种变化幅度超过鱼卵,底层重要经济种类早期补充群体优势度急剧下降;鱼卵和仔稚鱼物种多样性水平在升温季节较高而在降温季节较低,调查期内各季主要呈现先降后升变动趋势。鱼类早期补充群体种类更替现象明显,近年来种类更替率呈现明显加快趋势。各调查时期相同季节各适温类型产卵亲体种数均呈现先降后升变动趋势,但各适温类型种数所占比例和全年综合各适温类型种数所占比例基本稳定。各调查时期相同季节各主要栖所类型产卵亲体种类数也均呈现先降后升变动趋势,全年综合陆架浅水中上层鱼类种数所占比例升高,中底层和底层鱼类所占比例有所下降。近30年在多重外来干扰作用下,渤海鱼类早期补充过程各个关键环节已随其栖息地(产卵场)生境要素发生不可逆变化或变迁。渤海鱼类种群早期补充群体群聚特性和结构更替是环境-捕捞胁迫下鱼类群落内多重生态位的交替失调和渔业资源结构性衰退的具体表现。     

山苍子精油对辣椒疫霉生长发育的影响及对辣椒疫病的防效

为明确山苍子精油防治植物疫病的应用前景,在室内离体条件下测定其对辣椒疫霉Phytophthora capsici菌丝生长、孢子囊形成与萌发、游动孢子萌发的毒力,观测经山苍子精油处理后菌丝生长量及形态结构、细胞膜通透性和可溶性蛋白含量的变化;采用离体叶片法和灌根法分别测定山苍子精油对辣椒疫病的预防效果和治疗效果。结果表明,山苍子精油对辣椒疫霉的菌丝生长、孢子囊形成与萌发以及游动孢子萌发的有效中浓度EC_(50)分别为161.49、29.68、231.80、90.68 mg/L;EC_(50)和EC_(75)的山苍子精油处理显著降低了辣椒疫霉菌丝的鲜重和干重,抑制率均在49.71%以上,亦可显著降低菌丝中可溶性蛋白含量,抑制率分别为10.77%和18.47%;用山苍子精油处理菌丝后,其顶端生长受到抑制,分枝明显增多、间距缩短;细胞膜通透性增大。1 000 mg/L山苍子精油对辣椒疫病的预防效果达63.33%(离体叶片法),2 000 mg/L精油对辣椒疫病的预防效果和治疗效果分别达80.00%和68.00%(灌根法,7 d),均显著高于对照药剂嘧菌酯。表明山苍子精油是辣椒疫霉的有效抑制剂,在辣椒疫病综合治理中具有较大的应用潜力。