有棘和无棘两种表型栉江珧同工酶差异的比较

采用垂直板聚丙烯酰胺凝胶电泳对有棘和无棘两种不同表型的栉江珧的外套膜组织进行了ＥＳＴ和ＳＯＤ同工酶比较研究。结果显示这两种类型的酶谱表达有一定差异，但同时也存在中间类型，表明有棘和无棘的表型差异，尚不能提供它们应划分为两个种的充足证据。     

双棘黄姑鱼卵巢发育的周年变化

观察了双棘黄姑鱼卵巢发育的周年变化,结果表明,双棘黄姑鱼雌鱼性腺成熟系数(GSI)一年有两个峰值,分别出现在5月份(9.38%±0.32%)和10月份(7.56%±0.43%);HSI与GSI密切相关[R=0.76];卵巢发育水温在19～29℃范围,繁殖水温为24～28℃,在广东省饶平海区,双棘黄姑鱼繁殖时间在每年的5月和10月,属于春、秋二季产卵类型的鱼类。     

中国鲉形目棘鲬属一新纪录种——丝鳍棘鲬

【目的】记述中国南海海域棘鲬属的一新纪录种,以厘定中国南海海域棘鲬属的分类。【方法】2019年4月于中国南海北部海域海南岛东南渔场采集棘鲬属样品,采用形态学鉴定方法研究其形态特征,描述其生态习性,编制中国棘鲬属分种检索表。【结果与结论】样品中有6尾为中国新纪录种——丝鳍棘鲬Hoplichthys filamentosus Matsubara&Ochiai,1950。主要特征:体延长,平扁,向后渐狭小,背缘低平,腹缘平直;背鳍VI,14~15;臀鳍17;胸鳍13+ⅲ;腹鳍Ⅰ-5;尾鳍17;侧线骨板27;鳃耙2+11~12;体具几条不明显深色横带;胸鳍具黑色斑点;第1背鳍分布黄色斑点,具黑色小点和黑边;第2背鳍中部分布黄色圆斑,每1鳍条根部具黄色圆斑;腹鳍白色,无斑纹;臀鳍无明显斑纹;尾鳍后缘具黑边,中部较随机分布黄色圆斑,下叶颜色较深。该种雌雄异形:1)雄性下颌骨腹外侧具棘,雌性则隐没皮下;2)雄性第2背鳍鳍条均显著延长呈丝状,雌性则无显著延长。     

二长棘鲷和黄鳍鲷骨骼系统的比较

对二长棘鲷和黄鳍鲷的骨骼系统进行了比较研究。结果表明,二长棘鲷脑颅中的上筛骨、侧筛骨、额骨、眶下骨、蝶耳骨、上枕骨,咽颅中的前上额骨、腭骨、舌额骨、齿骨、鳃盖骨、尾舌骨、咽鳃骨等与黄鳍鲷相应部分的骨骼有明显差异,某些特征可作属间或种间的鉴别依据。     

脂肪水平对厚唇弱棘鯻生长及肠道脂肪酶活性的影响

以鱼油为脂肪源,配制成脂肪水平(质量分数,下同)分别为3.1%、5.8%、9.4%、11.9%和15.1%的5种等氮饲料,探讨饲料脂肪水平对初始体重为(4.05±0.11)g的厚唇弱棘鯻(Hephaestus fuliginosus)生长及肠道脂肪酶活性的影响。结果表明,随着饲料脂肪含量提高,实验用鱼脏体比、肥满度及肌肉粗蛋白含量也随着提高,但各组间差异不显著(P>0.05)。饲料脂肪水平从3.1%增加到9.4%,厚唇弱棘鯻的饲料效率呈升高趋势,相对增重率值由76.42%±5.88%升至102.09%±5.31%;而当饲料脂肪水平从9.4%提高至15.1%,饲料效率呈降低趋势(P<0.05),相对增重率值降为70.54%±2.06%。随着饲料脂肪水平提高,厚唇弱棘鯻肝体比、肌肉粗脂肪含量、肠道脂肪酶活性均呈上升趋势,且各组间差异显著(P<0.05)。表明本实验条件下饲料脂肪含量超过9.4%可导致厚唇弱棘鯻生长和饲料利用下降,对其形体特征、肌肉粗脂肪含量以及肠道脂肪酶活性均有显著影响。     

双棘黄姑鱼的人工繁殖及育苗技术

研究了2002-2003年双棘黄姑鱼(Nibea diacanthus)的人工繁殖、育苗过程。成熟亲鱼注射LRH-A HCG就可产卵，产卵率55．6％～83．3％，受精率71．0％～87．1％，孵化率77．9％～89．3％。苗种培育期间加强水质管理、饵料生物的营养强化和病害防治工作，在水温24．5～29℃、盐度26～32条件下，仔、稚、幼鱼生长迅速。     

不确定性对北部湾二长棘鲷渔业资源评估影响的模拟研究

利用蒙特卡罗模拟方法研究了生物学参考点F0.1、Fmax和当前捕捞死亡系数(current fishing mortality rate,Fcur)估计中的不确定性对北部湾二长棘鲷渔业资源评估的影响。结果表明:二长棘鲷渔业资源状态评估受到F0.1、Fmax、Fcur估计中的不确定性和管理者选取的决策置信水平的影响,二长棘鲷渔业被确定为过度捕捞的概率随着F0.1、Fmax、Fcur估计中不确定性和置信水平的增加而下降;F0.1和Fmax估计中的不确定性主要由生长参数的不确定性引起,自然死亡系数的不确定性对F0.1和Fmax估计中的不确定性的影响是有一定限度的。相比Fmax,将F0.1作为二长棘鲷渔业的管理目标更为合适。     

北部湾二长棘鲷生长、死亡及其群体组成

利用2006年7月至2008年3月北部湾渔业商业捕捞底拖网和刺网渔获物中采集的样本,对北部湾二长棘鲷的生长、死亡及其群体组成进行了初步研究。结果表明,北部湾二长棘鲷优势体长70～140 mm,占82.2%;优势体重为20～60 g,占54.29%;ARSS分析表明雌雄生长不存在显著性差异(P>0.05),繁殖期性比为1.21∶1;von Bertalanffy生长方程的主要参数分别为:L∞=292.8 mm,K=0.167,t0=-1.116;体重的生长拐点为5.463龄;总死亡系数、自然死亡系数和捕捞死亡系数分别为1.041 4、0.282 8和0.752 6,当前开发率为0.728。     

双棘黄姑鱼血清性类固醇激素的周年变化

采用放射免疫法(RIA)测定双棘黄姑鱼(Nibea diacanthus)血清性类固醇激素的周年变化。结果表明:雌鱼血清雌二醇(Estadiol-17β)浓度一年出现两次峰值,均在成熟产卵前一个月,即4月[(338±59)pg/mL]和9月[(296±48)pg/mL];血清睾酮(T)浓度在卵黄发生期急剧上升,并在卵巢成熟期达到最高值,分别是5月(2.506±0.262 ng/mL)和10月份(2.268±0.243 ng/mL),分别在血清雌二醇浓度两次峰值出现1个月之后,因此,雌鱼的血清雌二醇浓度和血清睾酮浓度均与性腺发育相关。雄鱼血清睾酮浓度的两次峰值均出现在性腺已发育成熟的5月份(2.307±0.792 ng/mL)和10月份(2.286±0.607 ng/mL),与性腺发育有明显的相关性;而血清雌二醇浓度全年维持在一个相对稳定的水平,与雄性性腺发育相关性不明显。     

双棘黄姑鱼的人工繁殖及育苗技术

研究了2002～2003年双棘黄姑鱼(Nibea diacanthus)的人工繁殖、育苗过程.成熟亲鱼注射LRH-A HCG就可产卵,产卵率55.6%～83.3%,受精率71.0%～87.1%,孵化率77.9%～89.3%.苗种培育期间加强水质管理、饵料生物的营养强化和病害防治工作,在水温24.5～29 ℃、盐度26～32条件下,仔、稚、幼鱼生长迅速.     

3种江珧同工酶遗传标记

通过对江珧科的栉江珧、旗江珧及二色裂江珧三物种的 5种组织 (消化盲囊、肾组织、外套膜、后闭壳肌和鳃组织 )进行垂直板状聚丙烯酰胺凝胶电泳分离技术 ,研究江珧科的 SOD、EST同工酶酶谱 ,结果表明 ,不同种间的个体其酶谱表型有稳定的差异 ,同属的种间差异小于不同属的种间差异 ,即酶谱的差异程度与形态分类学中的亲缘关系相关。可利用其酶谱表型具有种特异性作为一种蛋白分子标记 ,应用于江珧物种尤其是经济品种的鉴定上     

二色裂江珧EST和SOD同工酶组织特异性研究

取二色裂江珧 (Pinna bicolor)的消化盲囊、肾脏、后闭壳肌肌肉、外套膜和鳃等 5种组织 ,用垂直板聚丙烯酰胺凝胶电泳对酯酶 (EST)和过氧化物歧化酶 (SOD)同工酶在上述组织中的表达和分布进行了比较研究 ,并对酶谱表型及位点表达进行了分析。结果表明 ,二色裂江珧组织内的 EST和 SOD存在不同程度的组织特异性 ,EST共检测出 15条酶带 ,SOD检测出 8条酶带 ,且两种同工酶在消化盲囊中活性最高。推测 SOD由 2个座位编码 ,可分为 s- SOD二聚体和 m- SOD四聚体     

Local records of long-term dynamics of bamboo gregarious flowering in northern Laos and regional synchronicity of Dendrocalamus membranaceus in two flowering sites

Bamboos are widely distributed in mainland Southeast Asia and have abundant biomass. They are characterized by prolonged vegetative growth and semelparity. Where bamboos are dominant, their synchronous flowering and death has a major impact on forest vegetation. Although the small-scale dynamics of this process have become clearer in recent years, the history, geographical scale and synchronicity of bamboo flowering over broad areas remains unknown. This study focused on the flowering history of six bamboo species, Bambusa tulda, Cephalostachyum virgatum, Dendrocalamus hamiltonii, Dendrocalamus membranaceus, Indosasa sinica and Oxytenanthera parvifolia, over 40 years across a broad area of northern Laos. We also examined the synchronicity of flowering in D. membranaceus. We visited 49 villages in northern Laos and surveyed knowledgeable inhabitants about bamboo flowering history. The timing, scale and synchronicity of gregarious flowering varied among species. D. hamiltonii and D. membranaceus showed higher flowering synchronicity than other species. All the species except I. sinica had both sporadic and gregarious flowering traits, and showed conspicuous variability in their flowering scale. The flowering bamboo population at two gregarious flowering sites for D. membranaceus was surveyed. While thisspecies had the highest synchronicity in this study, its synchronicity was lower than other species in previous studies worldwide. We found that the gregarious flowering of bamboos in northern Laos over the last 40 years showed lower synchronicity than bamboo flowering reported in other areas of the world. The historical dynamics and scale of bamboo flowering must be further clarified to understand the vegetation composition of this area.     

韧性剪切带变形特征及控金机制——以丹东四道沟金矿为例

四道沟金矿位于丹东韧性剪切带中部。矿区出露岩石多为构造岩,依据变形强度可分为未变形残块(变质长石石英砂岩)、初糜棱岩(糜棱岩化变砂岩)、糜棱岩(主要是绢云石英糜棱岩)和超糜棱岩四类,横穿剪切带这四类岩石多次出现、规律组合。矿体产出的位置、形态以及矿化类型均受控于这几类岩石的空间分布格式。四道沟金矿的矿体产于中等变形程度的鳞片状构造带中,其上盘实际为一个巨大的变砂岩透镜体,它起了“封闭”的作用,使含金流体在其下盘聚集、沉淀,而鳞片状构造带下盘由糜棱岩和超糜棱岩组成的强变形带可透性好,为含金流体来源通道。在此基础上总结出韧性剪切带控金机制——金活化、迁移通道和聚集空间。     

Local records of long-term dynamics of bamboo gregarious flowering in northern Laos and regional synchronicity of <Emphasis Type="Italic">Dendrocalamus membranaceus</Emphasis> in two flowering sites

Bamboos are widely distributed in mainland Southeast Asia and have abundant biomass. They are characterized by prolonged vegetative growth and semelparity. Where bamboos are dominant, their synchronous flowering and death has a major impact on forest vegetation. Although the small-scale dynamics of this process have become clearer in recent years, the history, geographical scale and synchronicity of bamboo flowering over broad areas remains unknown. This study focused on the flowering history of six bamboo species, Bambusa tulda, Cephalostachyum virgatum, Dendrocalamus hamiltonii, Dendrocalamus membranaceus, Indosasa sinica and Oxytenanthera parvifolia, over 40 years across a broad area of northern Laos. We also examined the synchronicity of flowering in D. membranaceus. We visited 49 villages in northern Laos and surveyed knowledgeable inhabitants about bamboo flowering history. The timing, scale and synchronicity of gregarious flowering varied among species. D. hamiltonii and D. membranaceus showed higher flowering synchronicity than other species. All the species except I. sinica had both sporadic and gregarious flowering traits, and showed conspicuous variability in their flowering scale. The flowering bamboo population at two gregarious flowering sites for D. membranaceus was surveyed. While this species had the highest synchronicity in this study, its synchronicity was lower than other species in previous studies worldwide. We found that the gregarious flowering of bamboos in northern Laos over the last 40 years showed lower synchronicity than bamboo flowering reported in other areas of the world. The historical dynamics and scale of bamboo flowering must be further clarified to understand the vegetation composition of this area.     

Comparative studies on spectral properties of R-phycoerythrin from the red seaweeds from Qingdao

The present paper reports on comparative studies of R-phycoerythrin (R-PE) from 30 species of the red seaweeds in Bangiophyceae and in Florideophyceae from Qingdao. The measured absorption spectra show that R-PE from these red seaweeds have two spectral types, namely type I having two absorption peaks and type II having three absorption peaks. 9 specise of a lower red seaweed belonging to Bangiophyceae are all type I R-PE. 3 species of a higher red seaweed belonging to Florideophyceae are also type I R-PE. The remaining 18 species are all type II R-PE. According to the distribution of two types of R-PE in red algae, an evolutionary trend from type I R-PE to type II R-PE, can be seen, but this evolutionary process is more complicated and without a definite line of demarcation between the two spectral types of R-PE. The occurrence of two types of R-PE in red algae is of taxonomic significance. Project supported by the Science Fund of the Chinese Academy of Sciences. Contribution No. 1357 from the Institute of Oceanology, Academia Sinica.     

Diversity,composition and host-species relationships of epiphytic orchids and ferns in two forests in Nepal

Epiphytic plant species are an important part of biological diversity. It is therefore essential to understand the distribution pattern and the factors influencing such patterns. The present study is aimed at observing the patterns of species richness, abundances and species composition of epiphytic orchids and ferns in two subtropical forests in Nepal. We also studied the relationship of host plants (Schima wallichii and Quercus lanata) and epiphyte species. Data were collected in Naudhara community forest (CF) and the national forest (NF) in Shivapuri Nagarjun National Park. The data were analyzed using univariate and multivariate tests. In total, we recorded 41 species of epiphytes (33 orchid and 8 fern species). Orchid species abundance is significantly higher in CF compared to NF. Orchid species richness and abundance increased with increasing southern aspect whereas it decreased with increasing canopy cover, and fern species richness increased with host bark roughness. Orchid abundance was positively correlated with increasing bark pH, stem size, tree age and tree height and negatively correlated with increasing steepness of the area. Likewise, fern abundances were high in places with high canopy cover, trees that were tall and big, but decreased with increasing altitude and southern aspect. The composition of the orchid and fern species was affected by altitude, aspect, canopy cover, DBH, number of forks and forest management types. We showed that the diversity of orchid and fern epiphytes is influenced by host characteristics as well as host types. The most important pre-requisite for a high epiphyte biodiversity is the presence of old respectively tall trees, independent of the recent protection status. This means: (i) for protection, e.g. in the frame of the national park declaration, such areas should be used which host such old tall trees; and (ii) also in managed forests and even in intensively used landscapes epiphytes can be protected by letting a certain number of trees be and by giving them space to grow old and tall.     

Responses of tree species to climate warming at different spatial scales

Tree species respond to climate change at multiple scales,such as species physiological response at fine scale and species distribution (quantified by percent area) at broader spatial scale.At a given spatial scale,species physiological response and distribution can be correlated positively or negatively.The consistency of such correlation relationships at different spatial scales determines whether species responses derived from local scales can be extrapo-lated to broader spatial scales.In this study,we u...     

神农架林区植被分布与地形的关系研究

神农架林区是我国物种多样性最为丰富的地区之一,地形地貌复杂,对植被分布影响巨大。本文利用该地区2007年数字高程数据、2007年植被分布图以及2017年野外实地调查数据,基于最大熵模型和空间分析理论,从植被类型和种群两个角度研究该地区不同尺度植被空间分布的地形特征,分别量化植被类型和种群空间分布的地形范围,得到植被类型与地形因子关系模型、植被种群与地形因子关系模型。结果表明:①神农架林区影响植被空间分布的地形因子不同,其中影响针叶林分布的最重要的地形因子是高程和高程变异系数,影响阔叶林分布的是高程和坡向,影响灌丛分布的是坡向变率和坡向,影响草丛分布的较为分散;②典型植被种群分布的地形范围和植被类型的基本一致,其中90%针叶林分布在高程1600~2600 m间,典型种群巴山冷杉和华山松主要分布在高程1700~3200 m和1700~2200 m;85%的阔叶林分布在高程1000~2000 m间,典型种群青冈类和鹅耳枥主要分布在高程1200~2200 m间;95%的灌丛分布在坡向变率0~40°间,典型种群杜鹃和蔷薇主要分布在坡向变率小于40°的范围,但相应的关系模型存在差异,植被类型与地形因子为高斯模型,典型种群与地形因子关系模型相对复杂,不同种群的分布模式不同;③虽然坡度常作为数字地形的重要因子,但本文研究发现该地区坡度对植被类型和种群分布的影响不明显。研究结果可为神农架林区植被保护和恢复,以及植被规划和管理提供基础参考。     

Nematode Diversity of Qingdao Coast Inferred from the 18S Ribosomal RNA Gene Sequence Analysis

The 18S ribosomal DNA gene （18S rDNA） sequences （approxtmately 1300 bp in length） were amplified from the DNA extracted from the free-living marine nematodes collected from the inter-tidal sediment of Qingdao coast in bulk with nematode specific primers. The PCR products were cloned, re-amplified, digested with Rsa I and Hin61 restriction endonucleases and separated in agarose gel. Among 17 restriction fragment length types, types 1, 2 and 6 covered 61.2%, 14.4% and 9.3% of the clones analyzed, respectively, while the remaining 14 only covered 21 clones, which accounted for 15.1% of the total. Twenty-four representative clones were sequenced and phylogenetically analyzed by referring to those currently available in RDP and GenBank databases. Although it was hard to assign these sequences to known species or genera due to the lack of the 18S rDNA sequence data of known marine free-living nematodes, the obtained sequences were assigned to the nematodes of Adenophorea. Among them, twelve sequences were close to Pontonema vulgate and Adoncholaimus sp., four to Daptonema procerus and two （identical） to Enoplus brews. Our results showed that free-living marine nematode diversities could be determined by PCR retrieving and analysis of the 18S rDNA sequences and an 18S rDNA sequence could be assigned to a species or a genus only if the 18S rDNA sequences of the free-living marine nematodes were accumulated to some extent.