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1.
在宜黄开展对华南虎的野外调查,走访保护区范围内80%以上的村庄,大量华南虎在宜黄县境内的活动踪迹信息,表明宜黄境内有1~2个野生华南虎繁殖种群,数量5~8只.  相似文献   
2.
2001—2003年的20个月里,我们在中国湖南省壶瓶山国家级自然保护区内设置了一些触发相机,以确定该地区是否存在华南虎(Pantheratigrisamoyensis)。共设置r3种触发相机,包括TrailMaster(美国)的主动式和被动式相机以及WildlifeTwo(中国深圳)的被动式相机。首先在保护区西部沿着小路和动物足迹放置了一些相机。之后又从2002年开始在保护区东部追加放置了一些相机,这是因为有村民报告在这一区域发生了家畜丢失,发现猫科动物足迹以及听到吼叫声。在2002年5月到2003年12月的20个月期间,共8307个拍摄日,获得6180张照片,其中有1437张包括野生动物(平均每100个拍摄日17张野生动物照片)。合计拍摄到33种野生动物。,野猪(Susscrofa)、红腹锦鸡(Chrysolophuspictu.s)和毛冠鹿(Elaphoduscephalophus)是被拍摄最频繁的物种。既没有拍到虎和其他大型猫科动物,也没有拍到水鹿(Cervusunicolor)这种虎重要的猎物。最频繁被拍摄到的猫科动物是豹猫(Prionailurusbengalensis)。村民偶尔报告的掠走山羊的事件可能是豹(Pantherapardta)造成的,但是不能确定。利用触发相机调查超过1000d没有拍摄到虎,这一充分的证据足以支持该调查区没有虎的结论(d=0.05)。20个月超过8300个拍摄日没有在壶瓶山拍摄到虎,显示该地区没有虎。值得注意的结果是拍到红腹锦鸡、黄喉貂(Martesflavigula)、毛冠鹿和黑熊(Ursusthibetanus)的频率很高。这些物种是中国或国际受保护物种,包括被列为国内受保护物种,或同时列为国际受保护物种,又或者像毛冠鹿这种几乎是未知的物种。壶瓶山国家级自然保护区附近有3个保护区。我们讨论建议将这4个保护区合并为一个更大的保护地域来保护虎及其猎物。并且在此简要地评论了我们使用的3种触发相机的性能。  相似文献   
3.
为了解保存温度对野生动物粪样生殖激素检测结果的影响,采集21份雌性成年华南虎的新鲜粪样为试验对象,用Cat ELISA Kit测定在不同温度环境保存的粪样中雌二醇(E)、孕酮(P)、黄体生成素(LH)和卵泡刺激素(FSH)的浓度。结果:7份新鲜粪样,每份分成2份,分别直接冷冻干燥和-20℃保存后冷冻干燥,粪样中雌二醇、孕酮、卵泡刺激素和黄体生成素含量在两者间差异均不显著(P〉0.05);4份新鲜粪样,每份分成4份,分别置于25℃,4℃,-20℃和-70℃条件下保存24 h,粪样中雌二醇、孕酮、卵泡刺激素和黄体生成素含量在各处理间差异均不显著(P〉0.05);5份新鲜粪样,每份分成5份,-20℃保存9 d,粪样中雌二醇、孕酮、卵泡刺激素和黄体生成素含量始终均无显著差异(P〉0.05);5份新鲜粪样,每份分成5份,4℃保存9 d,粪样中雌二醇、孕酮、卵泡刺激素和黄体生成素含量始终均无显著差异(P〉0.05)。结果表明,应用Cat ELISA Kit检测华南虎粪样雌二醇、孕酮、卵泡刺激素和黄体生成素具有很好的稳定性,粪样在常温条件下短时间(9 d)保存不影响检测结果。  相似文献   
4.
5.
Pathological changes in cultured tiger puffer, Takifugu rubripes , with emaciation disease in Kyushu, Japan were studied histologically. In most cases, diseased fish were heavily infected with at least one of three myxosporeans ( Myxidium fugu , Myxidium sp. and Leptotheca fugu ) and two unidentified hyperparasitic microsporeans, attached to, or in, the intestinal epithelium. Myxidium fugu attached to the surface of the epithelium, caused no noticeable effects on the host tissue, irrespective of its infection with the hyperparasite. Myxidium sp., which proliferated in the epithelium, induced severe pathological changes including accumulation of cell debris between the epithelium and lamina propria and resultant detachment of the epithelium. Leptotheca fugu, another histozoic myxosporean, induced degeneration of the epithelium, associated with massive infiltration of macrophages into the epithelium to encapsulate parasites. When L. fugu was infected with its hyperparasitic microsporean, shortened villi were also observed. This is probably because passage of macrophage-parasite aggregates through the basement membrane of the epithelium severely damaged the epithelial structure. It is evident histologically that, unlike epicellular M. fugu , histozoic Myxidium sp. and L. fugu with or without hyperparasitic microsporeans, were highly pathogenic to host fish. This strongly suggests that they are causative agents of the emaciation disease.  相似文献   
6.
张胜利  林少华 《海洋渔业》2001,23(4):176-177
催产亲鱼采自泉州湾双斑东方鲀产卵场海区,经注射LRH-A催产激素,3个试验组有2组产卵,共产卵61万粒;在水温15-18℃条件下,受精卵经4d孵化,仔鱼全部出膜,共出苗30万尾。  相似文献   
7.
Wild tigers are being annihilated. Tiger range countries and their partners met at the 1st Asian Ministerial Conference on Tiger Conservation in January 2010 to mandate the creation of the Global Tiger Recovery Program to double the number of tigers by 2022. Only 3200–3600 wild adult tigers remain, approximately half of the population estimated a decade ago. Tigers now live in only 13 countries, all of which are experiencing severe environmental challenges and degradation from the effects of human population growth, brisk economic expansion, rapid urbanization, massive infrastructure development and climate change. The overarching challenge of tiger conservation, and the conservation of biodiversity generally, is that there is insufficient demand for the survival of wild tigers living in natural landscapes. This allows the criminal activities of poaching wild tigers and their prey and trafficking in tiger derivatives to flourish and tiger landscapes to be diminished. The Global Tiger Recovery Program will support scaling up of practices already proven effective in one or more tiger range countries that need wider policy support, usually resources, and new transnational actions that enhance the effectiveness of individual country actions. The program is built on robust National Tiger Recovery Priorities that are grouped into themes: (i) strengthening policies that protect tigers; (ii) protecting tiger conservation landscapes; (iii) scientific management and monitoring; (iv) engaging communities; (v) cooperative management of international tiger landscapes; (vi) eliminating transnational illegal wildlife trade; (vii) persuading people to stop consuming tiger; (viii) enhancing professional capacity of policy-makers and practitioners; and (ix) developing sustainable, long-term financing mechanisms for tiger and biodiversity conservation.  相似文献   
8.
Pond-breeding amphibians require aquatic and terrestrial habitats to complete their lifecycles, and preservation of both habitats is necessary for maintaining local populations. Current wetland regulations focus primarily on aquatic habitats, and criteria to define critical upland habitats and regulations to protect them are often ambiguous or lacking. We examined the association between the presence of seven pond-breeding amphibian species and the landscape composition surrounding 54 wetlands located within the Till Plains and the Glaciated Plateau ecoregions of Ohio, USA. We quantified landscape composition within 200 m of the wetland (“core terrestrial zone”) and the area extending from 200 m to 1 km from the wetland (“broader landscape context zone”). We constructed binary logistic regression models for each species, and evaluated them using Akaike Information Criterion. Presence of spotted salamanders (Ambystoma maculatum), Jefferson's salamander complex (A. jeffersonianum) and smallmouth salamanders (A. texanum) was positively associated with the amount of forest within the core zone. Presence of wood frogs (Rana sylvatica) was positively associated with the amount of forest within the core zone and the amount of forest within the broader landscape context zone. Presence of tiger salamanders (A. tigrinum tigrinum) was negatively associated with the cumulative length of paved roads within 1 km of the site, and presence of red-spotted newts (Notophthalmus v. viridescens) was negatively associated with the average linear distance to the five nearest wetlands. Overall salamander diversity was positively associated with the amount of forest within the core zone, and negatively associated with the presence of predatory fish and cumulative length of paved roads within 1 km of the site. Our results confirm the strong association between the structure of surrounding upland areas and amphibian diversity at breeding ponds, and stress the importance of preserving core terrestrial habitat around wetlands for maintaining amphibian diversity.  相似文献   
9.
红鳍东方鲀仔鱼期摄食与生长的研究   总被引:8,自引:2,他引:8  
在水温 ( 1 6± 1 )℃条件下 ,红鳍东方 (Takifugurubripes)仔鱼孵出后 4d开始摄食 ,此时其卵黄囊体积由初孵时的 0 636mm3减少到 0 375mm3;1 2d时 ,卵黄完全耗尽。最高初次摄食率出现在卵黄耗尽时 ,可达 1 0 0 % ;仔鱼能维持 9d高达 90 %以上的初次摄食率。初次摄食强度最大值也出现在 1 2d。饥饿不可逆点 (PNR)出现在 1 5~ 1 6d。在内营养期日平均增长率为 0 2 1 7mm/d ;在PNR前的摄食期 ,饥饿仔鱼的日平均生长率为 0 0 1 7mm/d ;而摄食仔鱼的日平均生长率为 0 0 95mm/d ;PNR后至死亡前 ,饥饿仔鱼呈负增长 ,而摄食仔鱼的日平均生长率达 0 41 0mm/d。  相似文献   
10.
对两则《武松打虎》的译文从语言美学的角度进行比较与分析,认为两则译文虽然在文体的处理上、在表现人物特点的翻译手法上、在人物的塑造和体现原文折射出的文化意境上稍有差别,但均忠实地传达了原文的全部信息,原文的语言特点在译文中基本上都得到了再现。  相似文献   
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