Soil quality index as a tool for Scots pine （Pinus sylvestris） monoculture conversion planning on afforested,reclaimed mine land

In Central Europe,a large portion of post-mining sites were afforested with Scots pine,which is characterized by good adaptability and a tolerance for poor habitat at the beginning of forest ecosystem development.Conversion of monoculture on mine sites into more biodiverse mixed hardwood forests,especially on more fertile deposits,can be an emerging need in this part of Europe in next decades.The ability to classify the forests at these post-mining sites will facilitate proper species selection as well as the management and formation of the developed ecosystem’s stability.This work describes the guidelines that can be followed to assess reclaimed mine soil(RMS)quality,using the mine soil quality index(MSQI)and a classification of developed forest sites as a basis of tree-stand species selection and conversion of pine monocultures.The research was conducted on four post-mining facilities(lignite,hard coal,sulphur,and sand pit mining areas)on different RMS substrates dominant in Central Europe.Soil quality assessment takes into account the following features of the soil:texture soil nutrients(Ca,Mg,K,Na,P);acidity(pH KCl);and Corg-to-Nt ratio in the initial organic horizon.An analysis was conducted of classification systems using the MSQI validation correlation(at p=0.05)with vegetation features affected by succession:aboveground biomass of forest floor and ecological indicators of vascular plants(calculated on the basis of Ellenberg’s(2009)system).Eventually,in the analysed data set,the MSQI ranged from0.270 for soils on quaternary sands to 0.720 for a mix of quaternary loamy sands with neogene clays.Potential forest habitat types and the role of the pine in the next generation of tree stands on different RMS parent rock substrate were proposed.     

农杆菌介导美味猕猴桃基因转化影响因素研究

[目的]建立美味猕猴桃叶片外植体转化体系,为猕猴桃遗传转化研究奠定良好基础.[方法]以美味猕猴桃组培苗叶片为材料,研究不同浓度乙酰香酮（AS）对外植体β-葡萄糖苷酸酶基因（GUS）瞬时表达阳性率的影响,及暗培养时间与抗褐化剂二硫苏糖醇（DTT）、聚乙烯呲咯烷酮（PVP）对外植体褐化、抗性芽诱导的影响.[结果]仅在侵染菌液中添加AS时,100、150、200 μmol/L AS 3个处理的外植体GUS阳性率均极显著高于对照,分别为14.6％、16.7％、10.7％;而当农杆菌侵染液与共培养基中同时添加100～150μmol/L AS,可使GUS瞬时表达阳性率提高至37.9％.选择培养初期经过2～12 d暗培养后,外植体褐化率不断下降,抗性芽诱导率不同程度提高,其中以暗培养6、8d处理的褐化率相对较低,分别为33.2％和30.6％,且相应的抗性芽诱导率最高,分别为14.2％和13.1％,极显著高于其他处理与对照.在分化培养基中添加1.0～2.0 g/L的DTT并暗培养6d的效果优于对应浓度的PVP;其中1.5 g/L DTT并暗培养6d,可使外植体褐化率降至13.4％,卡那霉素抗性芽诱导率提高至24.3％.卡那霉素抗性植株叶片GUS染色与PCR扩增结果显示,ShivaA基因已转化至美味猕猴桃秦美.[结论]AS不同使用方式及其浓度对叶片GUS瞬时阳性表达率的提高具有明显影响;选择培养初期进行暗培养6～8 d或暗培养结合添加1.0～2.0 g/L DTT抗褐化剂,均可降低美味猕猴桃叶片转化芽再生过程中的褐化,提高转化效率.     

不同饵料条件下玉筋鱼摄食、生长和生态转换效率的比较

将Eggers模型移入实验室大型玻璃钢水槽中,采用3种室内可能得到的实验饵料:冷冻细脚长(Themistogra cilipes)、天然成体卤虫(Artemissalina)和小黄鱼糜(Fishsilage),在流水条件下,比较黄渤海主要中上层小型鱼类玉筋鱼(Ammodytepersonatus)对上述3种饵料的摄食、生长和生态转换效率等生态能量学特征。结果显示,3种饵料中,虽然玉筋鱼对细脚长的能量生态转换效率较高,但是其湿重摄食量[g/(100g·d)FW]和能量摄食量[kJ/(100g·d)]都比较低,生长情况较差;卤虫的食物生态转换效率较高,湿重摄食量较多、生长情况较好;鱼糜的能量摄食量较多,生长情况介于两者之间,但其生态转换效率均较低。与自然生长的玉筋鱼相比,摄食卤虫的玉筋鱼较接近于自然生长。研究结论认为,室内玉筋鱼的模拟实验,在不能获得自然活体饵料的情况下,卤虫不失为一个理想的选择。     

Effect of glycine betaine, a feed attractant affecting growth and feed conversion of juvenile freshwater prawn Macrobrachium rosenbergii

A feeding experiment was conducted to determine the effect of the feeding attractant, glycine betaine (betaine hydrochloride) on the growth and feed conversion of juveniles of Macrobrachium rosenbergii (deMan) (mean initial weight 1.12 g). Three types of diets were prepared with the incorporation of glycine betaine at 5, 10 and 15 g kg^?1 levels along with an unsupplemented control. After 60 days, weight gain, feed intake and food conversion ratio (FCR) were higher in prawn fed the three glycine betaine‐added diets compared with the control feed. Among the glycine betaine‐added diets, prawn fed glycine betaine at 5 g kg^?1 level showed highest weight gain (2.73 g) by registering 61.5% increase in growth over control and also higher feed intake (5.79 g) and good FCR (2.12). There were highly significant differences (P < 0.01) in weight gain, feed intake, per day growth and FCR among treatments. There was no significant difference (P > 0.05) in survival among treatments.     

鱼粉质量对中国对虾、真鲷、饲料转化率和蛋白质消化率的影响

IntroductionInherent to the practice of intensive aquaculture is the generation of wastes having immediate and verybroad effects on the aquatic environment.There is a growing consensus about the need to reduce waste pro-duction in aquaculture to minimize the negative impacts on the environment.Nitrogen(N) and phosphorus(P) wastes are major concerns for many aquaculture operations.In the past,formulation of diets in intensive aquaculture was often aimed at meeting requirements formaximum growt…     

退耕还林工程建设对吴起县域植被碳储量的影响

采用标准样地调查结合数据分析的方法研究了吴起县退耕还林工程实施后,人工林的含碳率、碳储量及空间分布特征,结果表明：吴起县9类退耕还林地植被层总碳密度由大到小的顺序为：柠条〉刺槐〉沙棘〉紫穗槐〉臭椿〉山杏〉山桃〉侧柏〉油松,均大于天然草地的总碳密度;吴起县退耕还林12年后植被的总碳储量为152.53万t,是退耕还林前1998年总碳储量的3.2倍,且其空间分布也发生了较大的转变。吴起县退耕还林地的平均碳密度值远低于我国及世界各地森林平均碳密度的一些估计值,各类林地生态系统的碳储量还有很大潜力空间。     

矿井通风变频自动控制方法研究

现有矿井风机的工频供电控制方式已不能满足目前矿井现代化生产的需求。通过研究矿井风机传统控制方式,设计了矿井通风变频自动控制系统。该系统采用变频器对风机进行变频调速,以达到对风压和风量的自动控制;通过检测风机轴承和电动机温度,由中央控制单元自动切换备用风机,提高了矿井生产的安全性和可靠性。     

Dietary protein/energy ratios for Atlantic salmon in relation to fish size: growth, feed utilization and slaughter quality

Four extruded diets differing in protein/fat concentrations, 378/389 g kg^?1, 425/346 g kg^?1, 480/308 g kg^?1 and 524/256 g kg^?1 were tested in a digestibility trial and a growth study. Apparent digestibility of protein and fat were not significantly different among the diets when tested in 1-kg Atlantic salmon, Salmo salar L., in sea water. The diets represented a range of digestible protein to digestible energy ratios (DP/DE ratios) of 14.1, 16.4, 18.8 and 21.9 g MJ^?1. The 138-day growth study was performed with triplicate groups of Atlantic salmon of 1.0 and 2.5 kg initial weight. Irrespective of size; growth, feed conversion ratio (FCR), nitrogen and energy retention were poorer in fish fed the diet with DP/DE ratio of 14.1 g MJ^?1 compared with the fish fed the other diets. A DP/DE ratio of 16.4 g MJ^?1 was sufficient to produce maximum growth for the large fish, while the DP/DE ratio of 18.8 g MJ^?1 produced the highest growth in the small fish. In the large fish, the lowest FCR was obtained on a DP/DE ratio of 16.4 g MJ^?1, while there was no clear difference in FCR within the small fish when diets of DP/DE ratios of 16.4–21.9 g MJ^?1 were fed. The carcass-to-body ratio in the small fish decreased with decreasing DP/DE ratios. The fish fed the diet of 21.9 g MJ^?1 had significantly lower fat and dry matter and higher protein content than fish of similar size fed the other diets. Increased dietary lipid content seemed to improve astaxanthin deposition in the small fish, while the large fish showed no significant differences in astaxanthin deposition due to dietary treatment. This study indicates that a DP/DE ratio of 14.1 g MJ^?1 in high-energy diets for Atlantic salmon in sea water is below the optimal DP/DE ratio for growth and feed utilization, and that the optimal DP/DE ratio decreases with increasing fish weight. DP/DE ratios around 19 g MJ^?1 for fish weighing 1 to 2.5 kg, and 16–17 g MJ^?1 for fish weighing 2.5 to 5 kg, are suggested to be optimal.     

Photoperiod influences the growth, food intake, feed efficiency and digestibility of red sea bream (Pagrus major)

Two consecutive trials were conducted to investigate the effects of photoperiod manipulation on growth rate, food intake and feed conversion efficiency (Trial 1), and the digestibility of nutrients and energy (Trial 2) in red sea bream, Pagrus major (body weight 19–120 g). Fish were exposed to four photoperiods (6L:6D, 12L:12D, 16L:8D and 24L:0D) with light intensity 1500 lx on the water surface. The fish were fed with a commercial diet to apparent satiation. In Trial 2, 0.5% chromic oxide (Cr₂O₃) was used as an inert marker. Significantly higher weight gain and specific growth rates were observed in fish exposed to a 24L:0D photoperiod followed by 16L:8D, 6L:6D and 12L:12D photoperiods (P < 0.05). Food intake and feed conversion efficiency (FCE) were also significantly higher in fish exposed to 24L:0D followed by 16L:8D, 6L:6D and 12L:12D photoperiods (P < 0.05). Fish exposed to 24L:0D and 16L:8D photoperiods showed significantly higher lipid and energy digestibility than those exposed to a 12L:12D photoperiod (P < 0.05). The results demonstrated that the enhancement of growth performances under 16L:8D and 24L:0D photoperiods were attributed to improved appetite, greater food intake and higher feed conversion efficiency as well as higher digestibility.