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21.
大熊猫肌肉氨基酸含量的初步研究   总被引:3,自引:0,他引:3  
测定了3只大熊猫的头部、背部和腿部等10个肌肉样品中17种氨基酸(AA)含量,并分析了各样品AA与Lys含量的比值.结果表明:对同一只大熊猫,不同部位的肌肉样品中各AA含量无明显差异;对同一个肌肉样品,17种AA含量比较,Glu含量最高,Asp、Arg、Lys、Leu、Ala、Gly、Val、Pro、Thr、Phe等含量较高;不同年龄大熊猫肌肉AA含量有差异,除极少数AA外,未成熟雄性大熊猫肌肉AA含量高于成熟和老龄雌性大熊猫,且有显著性差异(P<0.05或P<0.01);成熟雌性大熊猫肌肉中,除Pro外,其余所有AA含量与其年龄无显著差异(P>0.05);除极少数AA外,不同年龄、性别大熊猫肌肉样品中各AA与Lys含量的比值无明显差异  相似文献   
22.
Abstract: The giant panda (Ailuropoda melanoleuca), is one of the world's most endangered species. Habitat loss and fragmentation have reduced its numbers, shrunk its distribution, and separated the population into isolated subpopulations. Such isolated, small populations are in danger of extinction due to random demographic factors and inbreeding. We used least‐cost modeling as a systematic approach to incorporate satellite imagery and data on ecological and behavioral parameters of the giant panda collected during more than 10 years of field research to design a conservation landscape for giant pandas in the Minshan Mountains. We identified 8 core habitats and 4 potential linkages that would link core habitats CH3, CH4, and CH5 with core habitats CH6, CH7, and CH8. Establishing and integrating the identified habitats with existing reserves would create an efficient reserve network for giant panda conservation. The core habitats had an average density of 4.9 pandas/100 km2 and contained approximately 76.6% of the giant panda population. About 45% of the core habitat (3245.4 km2) existed outside the current nature reserves network. Total estimated core habitat decreased between 30.4 and 44.5% with the addition of residential areas and road networks factored into the model. A conservation area for giant panda in the Minshan Mountains should aim to ensure habitat retention and connectivity, improve dispersal potential of corridors, and maintain the evolutionary potential of giant pandas in the face of future environmental changes.  相似文献   
23.
大熊猫基因组微卫生DNA的分离与序列分析   总被引:5,自引:0,他引:5  
以pBS^ 为克隆载体,构建圈养大熊猫基因组DNA的小插入文库,分别用生物素标记的(CAC)5和γ-^32P-dATP标记的(CA)15寡核苷酸为探针,对重组质粒进行斑点杂交,获得15个阳性克隆,并测定了插入片段的DNA序列,其中有一部分序列已被分析,本文对剩余的8个DNA序列进行分析,发现它们大小不一,从259bp-881bp,有6个序列含有不同重复单位的一、二、四核苷酸的完整串联重复,斑点杂交和Southern杂交证明,这些序列均来自大熊猫基因组,上述结果为利用PCR技术研究大熊猫遗传多样性和了解大熊猫基因组结构积累资料。  相似文献   
24.
秦剑  朱保林  陈艳  綦正信  赵刚  刘瑜 《灾害学》2012,27(3):69-74
对溪洛渡水电站坝址自动气象站进行了改造,在常规遥测雨量筒中加装了雨水温度传感器,得到了2010 - 2011年雨季地面雨水温度资料.在此基础上,对溪洛渡水电站大坝浇筑时碰到的降雨过程雨水温度骤降进行了分析及预报.结果如下:①2010-2011年溪洛渡水电站雨季降雨天气过程所引发的雨水温度骤降出现概率为37%,雨温骤降高值主要集中在7-8月;过程降雨量的大小并不能直接决定雨水降温的幅度,引起雨水温度骤降的因素较多.②利用90次降雨过程的历史数据建立了溪洛渡坝址站雨水温度变化最优子集回归方程,雨水温度骤降回代准确率为73%.该方程对雨水温度骤降的预报准确率达到75%,预报值与实测值的符号一致率达94.4%,表明该方程对溪洛渡坝址站雨水温度骤降预测效果较好.  相似文献   
25.
Loss of key plant–animal interactions (e.g., disturbance, seed dispersal, and herbivory) due to extinctions of large herbivores has diminished ecosystem functioning nearly worldwide. Mitigating for the ecological consequences of large herbivore losses through the use of ecological replacements to fill extinct species’ niches and thereby replicate missing ecological functions has been proposed. It is unknown how different morphologically and ecologically a replacement can be from the extinct species and still provide similar functions. We studied niche equivalency between 2 phenotypes of Galápagos giant tortoises (domed and saddlebacked) that were translocated to Pinta Island in the Galápagos Archipelago as ecological replacements for the extinct saddlebacked giant tortoise (Chelonoidis abingdonii). Thirty‐nine adult, nonreproductive tortoises were introduced to Pinta Island in May 2010, and we observed tortoise resource use in relation to phenotype during the first year following release. Domed tortoises settled in higher, moister elevations than saddlebacked tortoises, which favored lower elevation arid zones. The areas where the tortoises settled are consistent with the ecological conditions each phenotype occupies in its native range. Saddlebacked tortoises selected areas with high densities of the arboreal prickly pear cactus (Opuntia galapageia) and mostly foraged on the cactus, which likely relied on the extinct saddlebacked Pinta tortoise for seed dispersal. In contrast, domed tortoises did not select areas with cactus and therefore would not provide the same seed‐dispersal functions for the cactus as the introduced or the original, now extinct, saddlebacked tortoises. Interchangeability of extant megaherbivores as replacements for extinct forms therefore should be scrutinized given the lack of equivalency we observed in closely related forms of giant tortoises. Our results also demonstrate the value of trial introductions of sterilized individuals to test niche equivalency among candidate analog species. Equivalencia de Tortugas Gigantes de las Galápagos Utilizadas como Especie de Reemplazo Ecológico para Restaurar las Funciones de los Ecosistemas  相似文献   
26.
广西大石围巨型漏斗土壤中多环芳烃与环境因素   总被引:5,自引:4,他引:1  
孔祥胜  祁士华  蒋忠诚  黄保健 《环境科学》2012,33(11):3905-3915
选择典型的广西乐业大石围巨型岩溶漏斗(天坑)为研究对象,采集大石围漏斗不同部位的表层土壤,采用气象仪器观测大石围漏斗的环境因子,利用气相色谱-质谱仪(GC-MS)测定16种多环芳烃(PAHs)优先控制污染物.结果表明,大石围天坑群地表(正地形)土壤中ΣPAHs浓度范围为75.20~373.79 ng·g-1,平均值120.70 ng·g-1;地下(负地形)土壤,绝壁中ΣPAHs浓度范围为19.88~330.79 ng·g-1,平均值131.86 ng·g-1;底部中ΣPAHs浓度范围为127.48~661.62 ng·g-1,平均值395.22 ng·g-1;地下河(洞穴)中ΣPAHs浓度范围为1 132.11~1 749.95 ng·g-1,平均值为1 412.39 ng·g-1;土壤中PAHs以4~6环为主.比值法推断大石围漏斗土壤PAHs的来源主要为化石燃料燃烧源,主要污染途径为大气传输沉降.总体上,大石围漏斗土壤中PAHs浓度的空间分布随温差和相对湿度的升高呈现地面-绝壁-底部-地下河(洞穴)逐渐增加,PAHs显示"冷陷阱效应"的垂向富集与分异作用.影响PAHs分布的主要环境因素是温度,其次是湿度、风向和风速,在漏斗局部显示多环境因子共同作用.环境因子夏季影响大于冬季.监测发现,2007年比2006年大石围漏斗底部土壤中PAHs的浓度增加了3.5倍.因此,本研究提出巨型岩溶漏斗PAHs的富集和分异作用与环境因素密切相关.  相似文献   
27.
Abstract: In conservation biology, understanding the causes of endangerment is a key step to devising effective conservation strategies. We used molecular evidence (coalescent simulations of population changes from microsatellite data) and historical information (habitat and human population changes) to investigate how the most‐isolated populations of giant pandas (Ailuropoda melanoleuca) in the Xiaoxiangling Mountains became highly endangered. These populations experienced a strong, recent demographic reduction (60‐fold), starting approximately 250 years BP. Explosion of the human population and use of non‐native crop species at the peak of the Qing Empire resulted in land‐use changes, deforestation, and habitat fragmentation, which are likely to have led to the drastic reduction of the most‐isolated populations of giant pandas. We predict that demographic, genetic, and environmental factors will lead to extinction of giant pandas in the Xiaoxiangling Mountains in the future if the population remains isolated. Therefore, a targeted conservation action—translocation—has been proposed and is being implemented by the Chinese goverment.  相似文献   
28.
大熊猫幼仔口腔分泌物中检出聚团肠杆菌和微球菌   总被引:1,自引:0,他引:1  
大熊猫在圈养条件下 ,配种难、受孕难、幼仔成活更难已众所周知[1,2 ] .本文报告了一只患病大熊猫幼仔的静脉血、尿液和粪便的常规检测和细菌学分离、鉴定 ,并从该幼仔口腔分泌物中检出聚团肠杆菌和微球菌的结果 .以为大熊猫幼仔疾病的检测、诊断和治疗积累基础资料 .1 实验室检查大熊猫幼仔一只 ,1998年 9月出生于成都大熊猫繁育研究基地 ,初生重 110 g左右 ,出生第 3天 ,出现体温间隙性增高 ,拉血便 ,食欲减少 ,烦躁不安 ,精神状态较差 .1.1 常规检查用卡介苗注射用的针头采集颈静脉血作血常规检验 ,其结果 :白细胞总数 :2 3.6× 10 9/…  相似文献   
29.
收集并测定了8只圈养大熊猫的12个粘液样品的营养成分含量,包括水分、粗蛋白(CP)、粗脂肪(CF)、6种维生素(VA、VE、VD、VB1、VB2和VB6)以及4种微量元素(Fe、Zn、Cu和Mn).结果表明,大熊猫排泄的粘液营养物质含量丰富,尤其是含有很高的蛋白质、丰富的维生素和微量元素.粘液排泄频繁和排泄量大的大熊猫将从粘液排泄中损失很多的营养物质.因此,一方面必须给粘液排泄频繁和排泄量大的大熊猫补充营养,另一方面有必要采取切实可行的措施降低大熊猫的粘液排泄量及其频率.表4参5  相似文献   
30.
圈养亚成体大熊猫日粮粗蛋白表观消化率的初步研究   总被引:2,自引:1,他引:2  
研究了7只1.5-4.7岁的亚成体大熊猫对23种日粮粗蛋白的表观消化率(ADCP),结果为37.86%-83.70%。分析表明,对1.5-2.5岁的大熊猫,粗纤维采食量与ADCP有极显著的负相关关系(图1);对2.5-4.7岁的大熊猫。粗纤维采食量与ADCP没有明显相关关系(表3)。对1.5-2.5岁大熊猫,随竹粗蛋白占总粗蛋白比值升高,ADCP呈下降趋势(图2);2.5-4.7岁的大熊猫,ADCP随竹粗蛋白比例升高而呈上升趋势(图3);不同大熊猫ADCP还有个体差异。图3表3参10  相似文献   
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