各种类型河蟹育苗用水的水质分析

近几年,河蟹人工育苗已成为我省沿海种苗培育单位的重要产业 ,随着育苗规模的不断扩大及所带来的可观经济效益,各地又因地制宜发展起地下海水、浓缩海水的育苗生产,为搞清这几种育苗水体的水质特点 ,作者对这几种水体进行了分析检测,以服务于生产 ,为河蟹育苗的健康发展提供科学依据。１工作内容和方法１．１采样点自然海水采于营口市老边区三道沟和盘锦市二界沟;浓缩海水采于营口市青石岭育苗室及营口盐 　种型苗水ｐ ＣＤ营盐含量Ｔａｂ .1　ｐＨ ,ＣＯＤａｎｄｎｕｔｒｉｔｉｏｎｓａｌｔｏｆｅｖｅｒｙｋｉｎｄｏｆｂｒｅｅｄｉｎｇｗａ…     

黄龙洞年轻石笋的~(210)Pb测年研究

利用210Pb测年法对来自亚洲季风系统相互作用的青藏高原边缘区、高海拔的黄龙洞两根年轻石笋进行了测年研究,数据分析结果显示黄龙洞石笋顶部的210Pb放射性活度随距离呈指数衰变,衰变的趋势逐渐减缓,表明所研究的石笋中含有过剩的210Pb,样品顶部年龄小于100a。对黄龙洞石笋过剩210Pb数据进行非线性拟合,计算出两根石笋的平均沉积速率分别为0.104mm/a和0.143mm/a,与利用230Th测年法得到的沉积速率在定年误差范围之内一致,表明黄龙洞的210Pb测年数据是可靠的,通过计算石笋的沉积速率,可以建立近百年的石笋记录。研究表明,利用210Pb测年方法可以判断石笋(或石笋顶部)是否为100a内沉积的年轻石笋,弥补230Th法测定年轻石笋年龄的不足,有利于建立更加精确的石笋年代标尺,对探讨洞穴现代沉积记录和现代气象数据之间的相关性,明确洞穴石笋δ18O值所指示的气候环境含义具有重要意义。     

长心卡帕藻原生质体分离、培养研究

In this study, protoplasts were successfully isolated from Kappaphycus alvarezii using snail enzymes, abalone enzymes and cellulase. The optimum enzymic ratio was fixed to be 20% of abalone enzyme, 12% of cellulase and the osmotic stabilizer was 2.0 mol/L glucose. The optimum enzymic hydrolysis conditions were found to be dark enzymolysis at 30°C continuing for 4.0 h. The resultant density and yield of protoplasts achieved 32.60×104 mL-1, 65.20×104 g-1 tissue for Kappaphycus alvarezii. Finally, under the temperature of 20°C, light intensity of 1 500–2 000 lx and photoperiod of 12 h/d, two developmental pathways were investigated:(1) callus-like cell mass and regenerated plantlet occurred on protoplast;(2) young shoots and calluslike cell mass occurred in tissue blocks after enzymolysis.     

组织培养获得的海黍子幼孢子体的营养盐吸收和生长特性的研究

以组织培养间接获得的海黍子幼孢子体为实验对象,研究温度和氮、磷浓度对其营养盐吸收和生长的影响。结果显示,15~30℃范围内幼孢子体均可吸收NO-3-N、NH+4-N和PO3-4-P。25~30℃下NH+4-N的吸收显著高于10~15℃时,而NO-3-N和PO3-4-P的吸收速率在实验温度下差异不显著。NO-3-N、NH+4-N和PO3-4-P的最大吸收速率分别出现在15、25和25℃。当氮浓度3 000μg·L-1时,幼孢子体均可吸收NO-3-N和NH+4-N,且二者均呈现开放型吸收模式。当磷浓度30μg·L-1时,幼孢子体可吸收PO3-4-P,且呈现饱和型模式。温度对幼孢子体的生长影响显著。10~30℃范围内,富含氮磷组和去除氮磷组的特定生长率(SGR)均随着温度的升高先增大后减小,且最大SGR(分别为19.58%·d-1和14.58%·d-1)均在25℃时取得;叶绿素a、c的含量随着温度的升高先减小后增大。氮、磷浓度对幼孢子体的生长影响显著。富含氮磷组的SGR、叶绿素a含量和叶绿素c含量分别在15~25℃、15~30℃和20~30℃范围内显著高于去除氮磷组。     

培训视野中的高校青年教师成长服务研究

青年教师是我国高等教育事业发展的生力军。目前我国高校青年教师的培养存在"近亲繁殖"、重教学轻德育、重眼前轻长远等突出问题,这对于青年教师的成长极为不利。解决这一突出问题,需要通过师德建设、学术生涯规划、立体培训、国际交流等方式,进而提高为青年教师成长服务的工作质量,提升高校办学质量和服务社会的水平。     

Surface and subsurface water contributions to streamflow from a mesoscale watershed in complex mountain terrain

An understanding of surface and subsurface water contributions to streamflow is essential for accurate predictions of water supply from mountain watersheds that often serve as water towers for downstream communities. As such, this study used the end‐member mixing analysis technique to investigate source water contributions and hydrologic flow paths of the 264 km² Boulder Creek Watershed, which drains the Colorado Front Range, USA. Four conservative hydrochemical tracers were used to describe this watershed as a 3 end‐member system, and tracer concentration reconstruction suggested that the application of end‐member mixing analysis was robust. On average from 2009 to 2011, snowmelt and rainwater from the subalpine zone and groundwater sampled from the upper montane zone contributed 54%, 22%, and 24% of the annual streamflow, respectively. These values demonstrate increased rainwater and decreased snow water contributions to streamflow relative to area‐weighted mean values derived from previous work at the headwater scale. Young water (2.3 ± 0.8 months) fractions of streamflow decreased from 18–22% in the alpine catchment to 8–10% in the lower elevation catchments and the watershed outlet with implications for subsurface storage and hydrological connectivity. These results contribute to a process‐based understanding of the seasonal source water composition of a mesoscale watershed that can be used to extrapolate headwater streamflow generation predictions to larger spatial scales.     

Seasonal snow cover decreases young water fractions in high Alpine catchments

Estimation of young water fractions (F_yw), defined as the fraction of water in a stream younger than approximately 2–3 months, provides key information for water resource management in catchments where runoff is dominated by snowmelt. Knowing the average dependence of summer flow on winter precipitation is an essential context for comparing regional drought severity and provides the hydrological template for downstream water users and ecosystems. However, F_yw estimation based on seasonal signals of stable isotopes of oxygen and hydrogen has not yet explicitly addressed how to parsimoniously include the seasonal shift of water input from snow. Using experimental data from three high-elevation, Alpine catchments (one dominated by glacier and two by snow), we propose a framework to explicitly include the delays induced by snow storage into estimates of F_yw. Scrutinizing the key methodological choices when estimating F_yw from isotope data, we find that the methods used to construct precipitation input signals from sparse isotope samples can significantly impact F_yw. Given this sensitivity, our revised procedure estimates a distribution of F_yw values that incorporates a wide range of possible methodological choices and their uncertainties; it furthermore compares the commonly used amplitude ratio approach to a direct convolution approach, which circumvents the assumption that the isotopic signals have a sine curve shape, an assumption that is generally violated in snow-dominated environments. Our new estimates confirm that high-elevation Alpine catchments have low F_yw values, spanning from 8 to 11%. Such low values have previously been interpreted as the impact of seasonal snow storage alone, but our comparison of different F_yw estimation methods suggests that these low F_yw values result from a combination of both snow cover effects and longer storage in the subsurface. In contrast, in the highest elevation, glacier dominated catchment, F_yw is 3–4 times greater compared to the other two catchments, due to the lower storage and faster drainage processes. A future challenge, capturing spatio-temporal snowmelt isotope signals during winter baseflow and the snowmelt period, remains to improve constraints on the F_yw estimation technique.     

Nitrate removal and young stream water fractions at the catchment scale

Despite extensive research on nitrate export and removal, nutrient contamination remains a major threat to water bodies worldwide. At the local scale, nitrate removal is governed by biogeochemical conditions that vary in space and time, making integration to entire landscapes critical. Water transit times have often been used to describe solute transport, but the relation between water age and nitrate removal at the catchment scale is still poorly understood. We test the hypothesis that nitrate removal peaks when the fraction of young water in discharge is at its minimum, because nitrate removal occurs mostly under dry conditions where deeper, older groundwater dominates streamflow. We tested this hypothesis by exploring a detailed water quality record from the Kervidy–Naizin catchment (FR) and comparing the dynamics of nitrate to those of a conservative solute (chloride). We find that estimates of nitrate removal are consistent with previous estimates at the site and they show a good (inverse) correlation with the fraction of streamflow that is younger than 2.5 months. However, this young water fraction cannot be used to predict nitrate removal in the winter–spring period, when no removal is observed regardless of streamflow age. While this leads us to reject our hypothesis during the winter period, it also suggests that water age distributions and their correlation with nitrate removal can possibly reveal distinct sources of stream water at different hydrologic regimes and relevant biogeochemical reactions.     

6-9年生杉木幼林凋落物及其养分特征

根据定位观测的数据,探讨了2代杉木人工林幼林造林后6—9年凋落物数量及其养分特征,结果表明,在4a中,杉木幼林向林地输入凋落物共为1408．67kg·hm^-2,年均凋落量352．17k·hm^-2,6～9年的各年凋落量占总凋落量的比例为：19．84％、21．93％、28．51％、30．99％;在年凋落量中枝叶占多数,6～9年枝叶凋落总量分别为：233．43kg·hm^-2、264．80kg·hm^-2、334．09kg·hm^-2、354．11kg．hm^-2,年总凋落量、年枝叶凋落量均随着年份的增加而增加．在2002年、2003年和2004年夏季和秋季杉木幼林内凋落物的总量较多,冬季和春季较少,而2005年春季凋落总量最多,冬季最少．在凋落物各组分养分归还量中,杉木叶和其他叶N、P、K和C归还量较多,且年变化较大,杉木枝、其他枝、虫粪和碎屑N、P、K和C归还量较少,年变化亦较小．     

褐毛鲿人工繁育技术研究

褐毛鲿（Megalonibea fusca）属石首鱼科（Sciaenidea）,毛鲿鱼属（Megalonibea）,是朱元鼎等（1963）命名的新种.其为近海暖温性底层大型鱼类,具有重要的经济价值.1998年福建省水产研究所开展褐毛鲿人工繁殖和育苗在国内首获成功,二批共培育出幼鱼6.667×105尾,其中第一批平均全长为32.55 mm和37.55 mm的幼鱼共8.680×104尾,第二批全长为24.0～35.0 mm的幼鱼共5.799×105尾.对1998年褐毛鲿室内人工催产、仔稚幼鱼的培育技术、仔稚幼鱼的食性和生长发育、生态习性,以及早期发育稚鱼阶段的适盐生存下限进行了分析.褐毛鲿适宜的产卵水温为23.0～26.0℃,盐度为29～32.催产激素以DOM剂量为3.5 mg/kg和LHRH-A3剂量为4.5μg/kg混合使用效果最好.仔、稚、幼鱼培育饵料依次为牡蛎幼虫、轮虫、卤虫、桡足类,在水温为24.5～29.5℃,盐度为18～28条件下培育,25d龄鱼苗全长为19.0～26.0 mm,80%完成变态进入幼鱼期,育苗成活率达25.3%.褐毛鲿稚幼鱼适盐范围为4～38,属于广盐性种类,可在海水和咸淡水中养殖.