南美斑潜蝇及其寄生蜂消长规律

对云南省南美斑潜蝇及其主要寄生蜂潜蝇姬小蜂和潜蝇茧蜂的种群消长规律进行了研究。南美斑潜蝇在昆明关上菜区于 4、7、10月出现 3个高峰。潜蝇姬小蜂在春季蚕豆上种群数量较高 ,是控制南美斑潜蝇的主要蜂种。潜蝇茧蜂在秋季大棚内种群数量较高 ,是控制大棚南美斑潜蝇的主要蜂种。这两种寄生蜂对作物寄主有明显的选择性 ,潜蝇姬小蜂在春季的蚕豆、豌豆和芹菜上种群数量较高 ,潜蝇茧蜂在秋季的莴笋上种群数量较高     

兔肉的速冻

本文简单阐述了兔肉的速冻特点及规律 ,并对影响其质量的重要因素进行了分析 ,对兔肉的冷冻生产有指导意义     

牛卵泡卵母细胞的体外成熟和冷冻保存

在简化牛卵母细胞体外成熟的基础上,观察了保护剂、平衡温度、预平衡方法、解冻方法以及冷冻方法对牛卵泡卵母细胞冷冻的影响。结果表明:在体外成熟培养液中添加26.2 mmol/L的NaHCO3和对屠宰场卵巢进行选择更能促进牛卵母细胞的体外成熟;无论是程序冷冻还是玻璃化冷冻,乙二醇(EG)与甘油(GLY)相比更能促进牛卵泡卵母细胞的冷冻效果;在程序冷冻中,冷冻液中添加0.1 mol/L蔗糖比添加0.3mol/L的蔗糖更能促进牛卵泡卵母细胞的冷冻;在玻璃化冷冻中,37℃和25℃的平衡温度比4℃更适合牛卵泡卵母细胞的冷冻;在10%、5%、1%的预平衡浓度之间,5%的预平衡浓度即可达到预平衡的效果;在解冻时,多步脱除保护剂更能保护冷冻的卵母细胞;比较了几种最小样本量(minimum size sample,MSS)玻璃化冷冻方法,解冻成熟培养后的成熟率,拉细毛细玻璃管冷冻法为(41.67±3.19)%,极显著高于未拉细毛细玻璃管冷冻法(glassmicropipette,GMP)的(30.19±1.93)%和固体表面冷冻法(solid surface vitrification,SSV)的(28.33±2.89)%(P<0.01)。     

冷冻方法和冷冻保护液对山羊卵母细胞发育的影响

比较了不同冷冻方法和冷冻保护液对山羊卵母细胞冷冻-解冻后体外受精和激活后的发育效果.结果表明,开放式拉长塑料细管(OPS)法的效果好于玻璃化细管法和常规冷冻法;在OPS法中,20%EG 20%DMSO对卵母细胞的冷冻保护效果好于EDFS40,而在玻璃化细管法冷冻中,则是EDFS40好于20%EG 20%DMSO.对于常规冷冻法而言,则是1.5mol/L EG的冷冻效果好于1.5mol/L PROH.     

Seasonal stream habitat of adult Sakhalin taimen,Parahucho perryi,in the Bekanbeushi River system,eastern Hokkaido,Japan

Behavioural tracking of endangered adult Sakhalin taimen (Parahucho perryi) by acoustic telemetry was conducted in the Bekanbeushi River system that flows through eastern Hokkaido in 2008–2010. A total of 39 tracked P. perryi showed extensive use of the river system, both upstream and downstream, regardless of the month or year. No tracked adult P. perryi stayed in the ocean for more than 1 day. Some of the fish (20%) dwelled in upstream habitat consistently from spring to autumn, while 40% of individuals showed wide utilisation of the entire upstream and downstream systems. Although 39.4% of tracked fish utilised two or more primary tributaries to the main river, 6.1% used only the main river system. Distinct variability was observed between individuals based on the proportion of time spent in each stream reach (up‐, mid‐, and downstream). A trend was observed in 2008 and 2010 showing that tracked fish moved to the upper stream reaches when water temperatures downstream increased. This trend was not observed in 2009 when the summer water temperature downstream was more than 2 °C below average when compared to 2008 and 2010. Our results suggest that adult P. perryi in the Bekanbeushi River system exhibit high behavioural plasticity, that is, the fish can select habitats based on their own individual requirements. Our results also demonstrate the importance of physical continuity among river reaches both upstream and downstream such that P. perryi does not experience barriers in moving to optimal habitats.     

河龙水库溢洪道闸门冬季防冰冻措施的实施

阐述水库溢洪道闸门防冰冻的设备结构、安装和运行维护防法。延边河龙水库地处吉林省东部严寒地区,水库溢流坝闸门的冬季防冰冻措施尤为重要,该水库采用潜水泵直接射流方式,防止闸前冰冻,取得很好的效果。     

Effect of Freezing Snow Disaster on Forest Fuel and Fire Behavior in Southern China

After freezing snow disaster,stands of Pinus massoniana,Cunninghamia lanceolata. Liquidambar formosana,Cinnamomum camphora and Phyllostachys pubescens and new burned areas in Hunan Province were surveyed by setting field plots.Moisture content and fuel load were measured by sampling and fire behavior(such as rate of fire spread) was calculated.The results showed that fuel load got doubled instantly,fuel thickness enhanced,fuel continuity swelled and water content of fuel decreased as shrubs and herbs die...     

Photosynthetic Apparatus Responses to Short‐term low‐temperature Flooding May Contribute to Freezing Tolerance Changes in Forage Grasses

Winter conditions are subjected to rapid climate changes. Increased precipitation and snow melting during warmer winters may result in low‐temperature flooding. These factors probably affect plant overwintering strategies. This study investigated the relationships between the photosynthetic adjustment and freezing tolerance following a short‐term low‐temperature flooding in two forage grasses (Lolium perenne and Festuca pratensis). The effect of flooding on the photosynthetic apparatus acclimation to cold was determined using chlorophyll a fluorescence measurements. Freezing tolerance was estimated using an electrolyte leakage test. It has been shown that genotypes activating non‐photochemical mechanisms of photosynthetic acclimation to cold during low‐temperature flooding may show increased freezing tolerance. Freezing tolerance reduction observed in Festuca pratensis was probably connected with decreased photochemical activity and photoinhibition of photosynthesis. It can be concluded that photosynthetic apparatus response to low‐temperature flooding may contribute to changes in the freezing tolerance. The direction of the changes is associated with different photosynthetic apparatus performance.     

胶州湾典型站位小型底栖生物丰度和生物量的季节变化研究

2003年-2004年对胶州湾B2站小型底栖生物进行了7个航次的调查，结果表明B2站小型底栖生物的平均丰度是1889±609 ind.10cm-2，其中5月丰度值最高，为2721.5±776.7 ind.10cm-2，最低值出现在2003年9月，其丰度为1094.2 ±497.4 ind.10cm-2；平均生物量和生产量分别为1292.3±534.4μg dwt?10cm-2和11630.4±4809.5μg dwt?10cm-2?a-1。One-Way ANOVA分析表明，B2站小型底栖动物丰度和生物量存在显著的季节变化。共鉴定出17个小型底栖动物类群，其中线虫占绝对优势，其平均丰度是1801.82 ind.10cm-2，占小型底栖动物总丰度的95.4%。小型底栖生物数量与环境因子的相关分析表明，影响小型底栖生物数量发生季节变化的主要因子0-2cm表层Chl-a含量。     

湖北省近200年大冻年表的建立及频率特征的初步分析

本文根据历史文献灾情记载以及近代气象资料,按照一定标准,建立了湖北省过去204年(1805～2008年)大冻年表,并依据大冻年表分析了大冻的年代际变化、周期性及其与太阳黑子变化和拉马德雷现象的关系.结果表明:1)过去204年共发生大冻33次,平均每10年发生1.62次(约6.2年一遇);2)在冷期平均每10年出现2次大冻,而在暖期平均每10年出现1次大冻;3)20世纪70年代以前,大冻年存在准80、24、10、4～6年周期震荡,此后24、10年周期快速衰减,4～6年周期依然存在;4)近100年,在拉马德雷冷位相时期,大冻年平均每10年出现2.3次,重现期为4.3年;暖位相时期,大冻年平均每10年出现1.3次左右.重现期为7.5年左右;5)近200年的大冻年并不都出现在太阳黑子的峰值或谷值年,不过最近100年太阳黑子谷值年大冻出现频率增加.