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11.
西天目山土壤线虫区系与生态的初步探讨   总被引:3,自引:0,他引:3  
1987年5月由中国自然科学基金会资助,开始了“亚热带森林土壤动物区系及其在森林生态平衡中的作用”的研究工作,开选定浙江西天目山作为研究点之一。本工作在西天目山选定5个采样区。经鉴定,西天目山土壤线虫可分5目23属40种,其中有13种仅鉴定到属,并认为,土壤线虫数量的变化,主要与海拔高度、温度、土壤pH值、降水量等因素有关。  相似文献   
12.
ABSTRACT

In South America, Megalobulimus includes a number of threatened species, as well the largest land snails on the continent. The activity patterns and reproductive aspects of this group have not been documented. This work describes the daily and seasonal activity patterns and reproduction of M. paranaguensis. We maintained specimens in the laboratory for one year, and we quantified their behaviour for one hour at four different times of the day (0 h, 6 h, 12 h and 18 h) during three days in four months (August, September, April and May). The number of postures, hatching rate, time of hatching since oviposition and mortality rate among juveniles for each month were also quantified. Megalobulimus paranaguensis was more active in August, and had a egg laying peak one month after. Fifty-one eggs were laid by 12 captive individuals throughout the year, with a mean value of 4.25 eggs per individual. The hatching rate was 80.39%, and the time of hatching since oviposition was 56.7 ± 4.3 days. In two eggs, we observed the presence of twins. The mortality rate among juveniles was low (9.30%) indicating that rearing land snails in captivity has the potential to be an important and viable tool for the management and conservation of these organisms.  相似文献   
13.
利用气相色谱法,对姬松茸J3子实体油与原菌株J1子实体油中脂肪酸组成,不饱和脂肪酸含量等进行了比较研究.结果表明:姬松茸J3与原菌株J1脂肪酸GC指纹图谱极为相似,脂肪酸组成基本相同,但含量不同,姬松茸J3子实体油中亚油酸占74.0%、不饱和脂肪酸占74.7%;而生产上用原菌株J1子实体油中亚油酸占71.3%、不饱和脂肪酸占72.1%.表明姬松茸J3与原菌株J1的子实体油具有同样的开发价值.  相似文献   
14.
广西山口红树林自然保护区蝶类资源考察报告   总被引:5,自引:0,他引:5       下载免费PDF全文
陆温  韦绥概  覃爱枝  周放 《广西科学》2000,7(2):150-153
广西山口红树林自然保护区的蝶类有7科30属46种,以粉蝶科、蛱蝶科的种类较多,分别占总种类数的26.1%和23.9%.不同季节的蝴蝶种类和数量分布不均匀,春、夏、秋、冬季的蝴蝶种类数分别为15种、36种、39种和11种,捕获的数量分别占18.6%、32.2%、40.9%和8.3%.春季常见的蝶类为美目蛱蝶(Junonia almana almana)、珐蛱蝶指名亚种(Phalanta phalantha phalantha)、橙粉蝶(Ixias pyrene)和达摩凤蝶(Popilio demoleus)等;夏季常见蝶类为酢浆小灰蝶指名亚种(Pseudozizeeria maha maha)、幻紫斑蛱蝶海南亚种(Hypolimnas bolina kezia)、波蛱蝶(Ariadne ariadne)和青粉蝶海南亚种(Pareronia valeria hainanensis)等;秋季常见蝶类为虎斑蝶指名亚种(Danaus genutia genutia)、青粉蝶海南亚种(Pareronia valeria hainanensis)、紫灰蝶(Chilades lajus)和黑脉圆粉蝶指名亚种(Cepora nerissa nerissa)等;冬季的常见种为黑脉圆粉蝶指名亚种、无标黄粉蝶云南亚种(Eurema brigitta yunnana)和达摩凤蝶(Popilio demoleus)等.仅有6种蝴蝶可在一年四季采集到.区系成分以东洋种为主,占60.9%,东洋古北兼有种占36.9%,广布种仅占2.2%.蝴蝶群落多样性指数以秋季为最高.  相似文献   
15.
对贵州省兴义市坡岗自然保护区进行陆生贝类资源调查,共获得标本2 954号,经鉴定得66种(8个未定种),分隶于12科32属。区系分析表明:保护区内陆生贝类以东洋界种类为主,占种类总数的89%。东洋界西南区种类,占种类总数的33%;同时也有少数古北界的种类渗透,占种类总数的7%;广分布种类较少,仅占种类总数的4%。  相似文献   
16.
广西猫儿山叶蜂昆虫区系及地理分布   总被引:6,自引:0,他引:6  
对广西猫儿山进行叶蜂区系调查,鉴定整理出叶蜂昆虫134种,隶属3科63属.昆虫区系主要起源于东洋区,东洋种占总种数的65.67%.猫儿山叶蜂共计15种分布型,其中华中特有种所占比重最大,达58.96%.广西猫儿山与湖南有90个共有种,与四川有43种,与河南有39种;与云南(24种共有)的关系也比较密切,与西藏几乎没有什么联系.  相似文献   
17.
Parasites of the grey mullet Mugil cephalus collected from Lower K?z?l?rmak Delta in Turkey were investigated. Trichodina puytoraci, Trichodina lepsii, Ligophorus mediterraneus, Ligophorus cephali, Gyrodactylus sp., Microcotyle mugilis, Ascocotyle (Phagicola) longa, Haplosplanchnus pachysomus, Diplostomum spathaceum, Tylodelphys clavata, Posthodiplostomum sp., Neoechinorhyncus agilis and Ergasilus lizae were identified. Overall infection prevalence (%), mean intensity and mean abundance values were 99.61%, 458.10 ± 75.72 and 456.30 ± 75.44, respectively. Infection indices of parasite species in relation to season, lakes/lagoons and some physicochemical parameters of water such as temperature, salinity, dissolved oxygen and nitrate are determined and discussed. Posthodiplostomum sp. is a new parasite record for mugilids and Diplostomum spathaceum is the first record in M. cephalus, in the present study. Moreover, Ligophorus mediterraneus, Ligophorus cephali and Ergasilus lizae are new records for Turkish parasite fauna of fish and Mugil cephalus is a new host record for Neoechinorhyncus agilis in Turkey.  相似文献   
18.
19.
《Journal of Natural History》2012,46(11-12):651-667
We characterised the mite fauna associated with a subtidal population of Laminaria ochroleuca in the Cantabrian Sea during a 4-year study. We found 2780 individuals belonging to 35 species. The mite assemblage comprised both north Atlantic and Mediterranean species, as usually reported from the Lusitanian region. The most abundant and diverse subfamily was Copidognathinae, followed by Halacarinae and Lohmannellinae. The greatest abundance of mites was detected on kelp holdfasts, not only strictly phytal mites were found but also interstitial mites or those associated with other macrofauna. Such a distribution could be explained by the high diversity and heterogeneity of microhabitats provided by holdfasts. Mite abundance fluctuated during the 4 years of the study. However, the lowest abundance was detected during the last year of sampling. During that year, the studied algal population suffered a severe decay leaving only degenerating holdfasts attached to the substrate, which could explain the decrease in mite numbers.  相似文献   
20.
A new genus and species of the family Parabathynellidae, Sabahbathynella wongi, is described. It has been discovered in the interstitial of coarse sand filling the spaces between big stones of the bank along a stream in Sabah on Borneo. The new genus of the family Parabathynellidae exhibits some unusual features which make it impossible to assess its phylogenetic position. There are some convergencies with the genus Thermobathynella.  相似文献   
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