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1.
赛加羚羊(Saiga tatarica)在我国原产地的引种驯养   总被引:3,自引:2,他引:1  
从国内数次引种饲养实践及国外动物园饲养情况分析,赛加羚羊人工饲养成活率较低的主要原因为应激综合症。今后如能解决捕捉、运输、饲养等一些重要环节中存在的问题,饲养成活率将会逐渐提高。  相似文献
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自1988~1993年,结合《引进赛加羚羊驯化研究》,对赛加羚羊现代分布区、国内历史分布区和43个样点的11项气象地理要素计算欧氏距离和模糊相似优先化,并进一步作气候图解分析.发现引种区甘肃武威地区的生态环境与赛加羚羊现代分布区中的别特帕克达拉等地具有一定的相似性,气候类型介于哈萨克斯坦的半荒漠与荒漠草原之间,更相似于荒漠草原。认为赛加羚羊同其它生物种一样,有其特定的生态位,但随生态条件的变化而变化。要保证生态效能的充分发挥,赛加羚羊必须与环境统一,途径有三,其中在生态环境基本相似的区域内引种才是可行的。甘肃武威地区便是这种区域之一。进一步分析各种生态因子对环境的作用及物源状况十分重要  相似文献
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对散养在30hm^2场地内的塞加羚羊(Saiga tatarica)一个敏殖群体在2000年12月(酱期及其前、后)和2001年5-7月(哺乳期)的昼间时间分配做了观察研究。数据用个体扫描-瞬时取样法收集。结果表明:①雌性塞加羚羊在交配期结束后,躺卧时间减少,进食时间增加;从前期到后期,站立时间连续递减;母羊分娩后2周内离群单独活动,往返于觅食地和幼仔隐藏地之间;第3周起,母仔合群。②雄性在交配期的移动多于交配前,交配后躺卧时间增加。③塞加羚羊时间分配的性别差异始于交配期;这时,雄性个体忙于追逐圈赶雌性,导致移动时间增加,躺卧减少;交配期后,雌性觅食时间突增,而雄性不变;雌性进入哺乳期后,各月觅食时间均多于雄性。以上时间分配的性别差异反映了它们的繁殖投资差异。上述结果暗示,对此类散养动物,应在其能量需求高峰期增加投食量,以提高繁殖成功率。  相似文献
5.
刘荣堂 《生态学报》1997,17(2):151-158
自1988-1993年,结合《引进赛加羚羊驯化研究》,对赛加羚羊现代分布区、国内分布区和43个样点的11基气象地理要素计算欧氏距离和模糊相似优先化,并进一步气候图解分析,发现引种区--甘肃武威地区的生态环境与赛加羚羊现代分布区中的别特帕克达拉等地具有一定的相似性,气候类型介于哈萨克斯坦的增荒漠条件的而变化。要保证生态铲能的充分发挥,赛加羚羊必须与环境统一,途径有三,其中在生态环境基本相似的区域内引  相似文献
6.
刘荣堂 《生态学报》1996,16(1):65-70
通过对甘肃濒危野生动物繁育中心所在地──武威东沙窝及其周围地区植物区系调查,共获22科、84属、116种植物,以菊科、禾本科、藜科和豆科为主,占68.97%。以草本、、强旱生、中温、阳性、沙生等为主要生态型。以亚洲中部成分、地中海-西亚-中亚成分,为主要地理成分。植物类群接近赛加羚羊现代分布区植物类群,而且多数类群可被羚羊采食。  相似文献
7.
刘荣堂  陈本健 《生态学报》1996,16(3):265-268
在植物区系研究的基础上,作者于1988~1993年在甘肃省武威市进一步研究了赛加羚羊引种区的植物群落特征,观察了30种植物的物候期,用常规方法化验了72种植物的营养成分,从植被特征出发,综合评价其对赛加羚羊的适宜性。  相似文献
8.
Aim Long‐distance migrations of terrestrial animals, driven by needs such as food, water and escaping predators and harsh climatic conditions, are widely known phenomena. The saiga antelope (Saiga tatarica tatarica) migrates over long distances in the semi‐arid rangelands of Central Asia. Both the saiga’s range and its populations have been severely affected by socio‐political and land use changes over the last century, related to the formation and dissolution of the Soviet Union. We identified ecological drivers of saiga migration, compared four populations in terms of differences in the geographical characteristics of their ranges and the factors affecting habitat selection within the seasonal ranges. Location Kazakhstan and pre‐Caspian Russia. Methods Using 40 years of direct observations, we tested for differences between the four saiga populations’ ranges in terms of precipitation, seasonal productivity and topographical variables using discriminant analyses. We tested hypotheses concerning the drivers of migration to their seasonal ranges and assessed the impact of peak and average values and the predictability of drivers of habitat use within the seasonal ranges using logistic regressions. Results Three of the four populations migrate in a similar way, following a latitudinal gradient driven by seasonal changes in productivity, which is closely related to broad‐scale differences in precipitation. Intermediate productivity and its low interannual variability determine habitat selection within the seasonal ranges of all the populations. Main conclusions Migration of all four populations is driven by productivity and precipitation. The migrations in Kazakhstan are still intact despite major recent disruption to the populations, whereas their status in the pre‐Caspian region is unknown. All four populations are under severe threat from habitat loss, poaching, lack of protection and gaps in ecological knowledge. A better understanding of the drivers of saiga migration at multiple scales is a key step towards addressing these threats.  相似文献
9.
In polygynous mammals, males generally benefit more from extra allocation of maternal resources than females. However, limitations to sex-specific allocation are usually ignored. We propose the 'allocation constraint' hypothesis, whereby maternal resource allocation is more likely to follow life-history predictions in single sex litters than in mixed sex litters, due to limitations in prenatal resource targeting. Consequently, for polygynous species, males in mixed litters are likely to receive suboptimal maternal investment, which may have a negative effect on lifetime reproductive success. We test this hypothesis for the saiga antelope (Saiga tatarica), a highly polygynous species with the highest level of maternal allocation reported among ungulates. At such high reproductive output levels, the limitations on additional investment in males are likely to be particularly acute. However, we demonstrate high levels of sexual dimorphism in both late-stage foetuses and newborn calves, including within the same litter. Male twins with a brother tended to be heavier than those with a sister. This may be due to allocation constraints or differences in maternal quality. We conclude that an explicit focus on potential constraints can enhance the progress in the field of sex-specific maternal allocation in polytocous species.  相似文献
10.
2018年4月下旬至5月初对国家林业局甘肃濒危动物保护中心的61只初生赛加羚羊(Saiga tatarica)成活率、性别比例、单双羔比例、初生重等生物学数据进行了观测,并对结果进行归纳分析。赛加羚羊分娩期始于4月25日,截止于5月5日,产羔高峰期集中在4月28日至5月2日。共分娩61只羔羊,成活56只,成活率91.80%。其中,雄性羔羊占40.98%,雌性羔羊占59.02%,雌雄性别比(♀︰♂)为1.44︰1,与1︰1的性比差异不显著(χ2检验,P 0.05);单羔比例80.33%,双羔比例19.67%,两者差异极显著(P 0.01);初生羔羊体重多数集中在2.501~3.000 kg,雄性羔羊平均初生重略高于雌性羔羊,单羔羚羊平均体重略高于双羔羚羊。单羔雄羚羊与双羔雄羚羊、单羔雌羚羊与双羔雌羚羊以及单双羔、雌雄羔羊总平均体重间的差异均不显著(P 0.05)。  相似文献
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