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1.
根据重捕次数,对双山山地麻蜥种群数量进行了初步统计,结果表明,1997-1998年度,该种群数量为200余只;1999-2000年度,该种群数量为60余只。并初步分析了该状况的成因,提出保护该蜥种的几点建议。  相似文献   

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山地麻蜥生态的初步研究   总被引:1,自引:0,他引:1  
山地麻蜥主要栖息在市郊海拔大于100m的山丘上部及山顶。研究结果表明,山地麻蜥正常密度大约为1只/100m^2,其数量与山丘土石状况、植被盖度及海拔高度有一定关系,与植被类型关系不大。山地麻蜥似乎有一定的“护洞”行为。主食昆虫和蜘蛛,春季食物生态位宽度大于秋季,食物生态位重叠度为0.61。性比变化较大,出蛰仞期和冬眠前期雄多雌少;而5~10月份期间,性比接近1。幼体至成体发育期间,雄性生长快于雌性;但成年期后,雌性头体部分的生长快于雄性,可能与怀卵有关。山地麻蜥种群可分为4个年龄组,个体数量比约为幼年:亚成年:成年A:成年B≈1.8:1.9:3.1:1,但成体与非成体的数量比约为1.2:1,应属于稳定型种群。个体自然寿命约为5.5~6周年。人类干扰是山地麻蜥种群下降的原因之一。  相似文献   

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桓仁滑蜥分布区域狭窄,种群数量极为稀少。大量农田的开垦使得该物种栖息地遭到严重破坏,这是导致其种群数量下降的直接原因;其次,大量捕捉使得这一物种遭受了更为严重的生存压力。对野外捕获的12只桓仁滑蜥(Scincella huanrensis)进行实验室内饲养,现简要报道。  相似文献   

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三化螟种群动态分析及防治   总被引:3,自引:0,他引:3  
蓝学明  杨凤  梁葵珍 《昆虫知识》2002,39(2):113-115
分析了 1 980~ 2 0 0 0年三化螟种群数量变动情况 ,发现年度间的变动不一致 ,有明显间歇性。认为冬春气候 (气温、雨量 )、耕作制度、天敌因素等与三化螟为害密切相关 ,并提出科学实用的防治方法  相似文献   

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矮岩羊种群生态的初步研究   总被引:8,自引:0,他引:8  
利用路线调查方法分别于 1998年 3月、7~ 8月和 2 0 0 0年 5~ 8月对四川省巴塘县的矮岩羊 (Pseudoisschae feri,亦称倭岩羊 )种群进行了初步研究。结果显示 ,矮岩羊目前主要栖息在巴塘县竹笆笼到苏阿龙一带的河谷以及支流两侧地势陡峭的悬崖绝壁上的岩壁草丛中 ,在面积大约 2 0 0km2 的范围内活动 ,种群数量大约在 14 1只左右 ,活动群体的大小为 2~ 10只 ,种群平均密度为 0 .70 5只 /km2 ,种群雌雄性比为 10 0 :70 .4。幼体组、亚成体组、成体组分别占所观察到总数量的 13.0 %、2 9.8%和 5 7.2 %。矮岩羊生性胆小 ,易受惊吓 ,休息时喜欢用前脚刨地 ,这个动作约占休息时间的 1/3。从 2 0世纪 5 0年代以来 ,矮岩羊的种群数量下降很快 ,森林面积的锐减、人为猎杀、过度放牧是影响矮岩羊生存环境和种群数量的主要原因  相似文献   

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桓仁滑蜥(Scincella huanrensis)系卵胎生,1年生殖1次,生殖季节为7月下旬到8月上旬。平均每只雌蜥产仔4.556(2~6)只。雌蜥的分娩在洞穴中进行,分娩时间可持续60-90min,仔蜥在产出时卵膜已破裂。雌性采取的是高投入的生殖策略,平均生殖投入率0.436(0.212~0.526)。相关性回归分析表明:窝仔数与雌蜥体重、体长和生殖投入呈正相关关系;生殖投入与雌蜥的体重和体长不相关;幼蜥的体长、体重与窝仔数呈负相关关系。  相似文献   

7.
山地麻蜥繁殖生态的研究   总被引:8,自引:2,他引:6  
1997年 3月到 1 998年 8月 ,在徐州市近郊的牛头山对山地麻蜥的繁殖生态进行了研究。 3~ 7月为繁殖期 ,其中 4~ 5月为交配产卵盛期。雌雄性比为 1∶1 6。从交配到产卵为 2 6天。卵白色、革质、椭圆形。长径平均为 1 3 7( 1 2 3~ 1 53 )cm ,短径平均为 0 86( 0 7~ 1 0 6)cm ,卵重平均为 0 6( 0 4~0 85) g。每窝平均产卵 4 1 ( 3~ 5)枚。孵化期为 50天。初孵出的小麻蜥尾端为蓝绿色 ,有金属光泽 ,1个月后逐步消失。  相似文献   

8.
桓仁滑蜥的现状及其保护   总被引:2,自引:2,他引:0  
董丙君 《四川动物》2005,24(3):279-280
桓仁滑蜥仅分布于我国辽宁省桓仁县很狭窄的区域内,种群数量极其稀少,而且由于人类生产活动的影响和猎捕,已经导致该物种处于极度濒危状态。本文对桓仁滑蜥生物学特性及其生活环境进行了简要的描述,希望能够引起相关部门的重视,尽快采取有效的保护措施。  相似文献   

9.
两种有鳞类爬行动物消化道微生物的研究   总被引:1,自引:0,他引:1  
从北草蜥的胃、小肠和大肠中分离出 7个属 8种细菌和 2个属的霉菌 ,从中国石龙子的胃、小肠和大肠中分离到 6个属 7种细菌和 3个属的霉菌 ,酵母菌和放线菌都未发现。北草蜥胃、小肠和大肠中的细菌数量分别为 2 2 7× 1 0 6,2 0 6× 1 0 6和 9 78× 1 0 8个 / g ;霉菌数量为 2 5× 1 0 4 ,2 1 5× 1 0 4 ,1 33× 1 0 4个 /g。细菌在中国石龙子胃、小肠和大肠中的数量分布依次为 3 51× 1 0 6,2 2 5× 1 0 6,1 4 2× 1 0 9个 /g;霉菌分布数量为 2 1 9× 1 0 4 ,1 67× 1 0 4 和 1 61× 1 0 4 个 / g  相似文献   

10.
董丙君 《四川动物》2005,24(3):279-280,F0009
桓仁滑蜥仅分布于我国辽宁省桓仁县很狭窄的区域内,种群数量极其稀少,而且由于人类生产活动的影响和猎捕,已经导致该物种处于极度濒危状态。本文对桓仁滑蜥生物学特性及其生活环境进行了简要的描述,希望能够引起相关部门的重视,尽快采取有效的保护措施。  相似文献   

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K. Hausmann 《Protoplasma》1979,100(2):199-213
Summary The membranes of the pellicle of the ciliatePseudomicrothorax dubius are investigated using thin section electron microscopy and freeze-fracture replicas. The plasma membrane is covered by a surface coat and is connected to the outer alveolar membrane by short, sometimes branched, bridges. The inner alveolar membrane is coated on both sides. The epiplasm lies in intimate contact with the cytoplasmic surface of this membrane, and there is a corresponding deposit on the other surface. This deposit is regularly striated.The epiplasmic layer and the alveoli are interrupted at sites of cytotic activity,e.g., the attachment sites of trichocysts, the cytoproct, and the parasomal sacs. The striated deposit ends where the epiplasm ends, indicating a direct relationship between these two epimembranous layers.There is a deposit along the sides of the first part of the tip of the trichocysts, and in this region the trichocyst membrane is free of intramembranous particles.The membrane of the parasomal sacs has a coat on both surfaces. That on the extraplasmic surface is similar to the surface coat of the plasma membrane. The origin of the cytoplasmic coat is unknown. The cytotic activity of these sacs is indicated by their highly irregular profiles.  相似文献   

13.
Summary The differentiation of the spermatid, especially in reference to the formation of the flagellum, and transformation of the shape of the nucleus was investigated in the domestic fowl.In the early stage of the spermatid, a prominent Golgi apparatus appears around the centrioles. The Golgi vesicles then surround the axial-filament complex which develops from the distal centriole. These vesicles fuse to form continuous membrane at the earliest stage of flagellar formation, and in the succeeding stage Golgi lamellae are attached to the plasma membrane of the developing flagellum. From these observations, it is assumed that Golgi apparatus may be a source of the membrane system of the flagellum.The microtubules distributed around the nucleus form the circular manchette. The anterior region of the nucleus with the manchette is cylindrical in shape and the posterior region without it remains irregular in shape. When the circular manchette has been completed, the whole nucleus acquires a slender cylindrical shape. The circular manchette then changes into the longitudinal manchette. The nuclei of spermatids without a longitudinal manchette are abnormal in shape. In view of these observations it is assumed that the nuclear shaping of the spermatid may be accomplished by circular manchette and the maintenance of shape of the elongated nucleus by longitudinal manchette.The authors wish to thank Mr. Takayuki Mori for his helpful suggestions and technical advices  相似文献   

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This study aimed to analyze the aqueous humor (AH) and the vitreous body (VB) of the eye of the adult frog Rana temporaria L. as a representative species of amphibians, which lead a semi-terrestrial life. The presence of collagen, albumin, uric acid and electron donors was shown in both media; however, there are slight differences in their concentrations. To determine collagen, a spectral-fluorescent probe, cyanine dye, was used. The presence of collagen in AH of the frog was found at the first time. The total content of electron donors (ascorbic and uric acids, tryptophan, and tyrosine) in VB and HA was roughly estimated at ~ 1.5 × 10− 4 mol/L. Both VB and AH absorb light in similar UV regions. The total protein and albumin contents in AH were found to be somewhat higher than those in VB. The uric acid content was at an equally low level in both intraocular media. It is supposed that the similarity of VB and AH compositions shown in this work is due to some exchange between VB and AH contents in the course of accommodation. The role of intraocular fluids in physiological functions of the eye and in protecting the retina against UV light is discussed.  相似文献   

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