Electrophoretic and meristlc separation of blue maomao and sweep P. J. Smith,B. A. Wood,and P. G. Benson

Fourteen proteins and 12 morphometric characters were examined in specimens of blue maomao and sweep to resolve the question: Are they one or two species? Specimens were fixed for the same alleles at 12 protein loci and shared alleles at 4 polymorphic loci. At a further polymorphic locus they differed in allele frequency and at three loci they did not share alleles. A genetic distance of 0.209 was found between blue maomao and sweep suggesting that they diverged about 1 million years ago. One meristic character showed a difference between specimens.

On the basis of the electrophoretic data and on gill raker counts it is considered that blue maomao and sweep are two separate species. In view of reported differences from Australian specimens the allocation of scientific names at least to sweep remains uncertain.     

长毛对虾、短沟对虾和日本对虾的染色体研究

目前,利用高新技术,如实行生殖和遗传操作进行对虾品种改良的设想正在中国、美国、澳大利亚和日本等国加紧实施,但对虾遗传和生殖学研究尚欠深入,限制了这项研究的进展。其中对虾染色体知识的贫乏和研究技术的短缺就是突出的一例。     

Effects of Light,Salinity and Temperature on Germination Characteristics of Surfgrass,Phyllospadix japonicus and P. iwatensis Seeds

Ocean Science Journal - Surfgrass (Phyllospadix spp.) is a marine flowering plant that attaches to the bedrock of the Pacific Ocean, where the tide is fast and the waves are strong. In Korea, two...     

南疆博斯腾湖近12.OkaB.P.以来古气候与古水文状况的变化

对南疆博斯腾湖湖相沉积物多手段的综合研究，揭示了近12.0kaB.P.以来古气候与古水文状况的变化过程与特征。结果表明，其气候的演化特征具有明显的西风型环境演变特征。研究还发现气候于12.0ka、10.0ka、4.0ka和1.5kaB.P.存在显著的阶梯式增暖变干特征，其中暖峰主要出现于11.5—11.0ka、9.4ka、7.5—7.0ka、6.5—6.0ka、3.0ka和2.0kaB.P.，气候特征以干暖为主，湖泊水文特征总体表现为盐度增加、水位下降、湖面缩小；而冷峰主要出现于11.0—10.0ka、8.8ka、5.0—4.5ka、3.3ka和1.5kaB.P.，此时湖泊膨胀淡化，湖面上升。在7.0—5.0kaB.P.期间出现的相对暖湿环境特征可能是全新世大暖期最盛期暖湿气候特征的反映，可能与此时西南夏季风势力增强有关，湖泊水文状况明显变好。     

中国对虾、墨吉对虾和长毛对虾仔虾的发育比较研究

中国海域已报道的约90种对虾中,半数具有经济价值。其中中国对虾、墨吉对虾和长毛对虾无论在捕捞还是在养殖业上都具有十分重要的地位。由于3种虾的形态非常相近,特别是在早期生活史阶段,它们的幼体和仔虾很难区分,因而给对虾种群补充、预报和其它有关研究造成困难。尤其在热带海域,对虾生殖季节重叠,幼体和仔虾的鉴别更加重要,各期仔虾的数量统计需以严格的形态鉴别作为依据。作者对三种对虾的幼体的形态,区别已有专文报道(Liu and Liu,1994)。本文深入细致地研究了中国对虾、墨吉对虾和长毛对虾仔虾的发育形态学,并进行了比较,使3种对虾的仔虾得以区别,并为今后的对虾生态学研究及资源管理奠定基础,提供依据。