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1.
We collected data on diet and activity budget in a group of Rhinopithecus bieti at Tacheng (99°18E, 27° 36'N, between 2,700–3,700 m asl), Yunnan, from March 1999 to December 2000. We mainly recorded species-parts eaten with feeding scores from scanning state behaviors of one-male units in tree-crowns. We also conducted microscopic analysis of feces collected monthly. The subjects consumed 59 plant species, belonging to 42 genera in 28 families, of which 90 species-parts were distributed as follows: 21 in Winter, 38 in spring, 39 in Summer, 47 in autumn. Conversely, the group annually spent, on average, 35% of daytime feeding, 33% resting, 15% moving, and 13% in social activities. Seasonal changes are apparent in daytime budget and food item-related feeding time in tree-crowns, food remains in feces, and the number of species-parts eaten. Correlations within and between food items and time budget clearly indicate maximization of foraging effectiveness and minimization of energy expenditure. In consideration of reports from northern and southern groups, that which underlay the specific adaptation to the habitat appeared to be similar to those of other colobines. Thus, the ultimate factors for survival of the species are more hopeful than expected. 相似文献
2.
Habitat Degradation of Rhinopithecus bieti in Yunnan, China 总被引:3,自引:0,他引:3
Wen Xiao Wei Ding Liang-Wei Cui Ru-Liang Zhou Qi-Kun Zhao 《International journal of primatology》2003,24(2):389-398
Black-and-white snub-nosed monkeys (Rhinopithecus bieti) are endemic to the Trans-Himalayas in Northwest Yunnan and Southeast Tibet between the upper Yangtze and Mekong Rivers. Based on field surveys and previous reports, we identified the dark-coniferous forest, the mixed coniferous and broadleaf forest, and oak patches as suitable habitats (SH) for the monkeys. Summer grazing lands (SGL), which were made by local people cutting and burning the dark-coniferous forest at the high altitude belt, replaced SH. To have a general view of the status of the SH in Yunnan, we estimated the areas of SH and SGL from satellite images in 1997, and compared with areas estimated from aerial photo-based maps (ca. 1958). The work resulted in: 1) the area of SH was 4,169 km2 in 1997; 2) SGL was 1,923 km2; 3) during the past 40 years, the area of SH decreased by 31% (1,887 km2), and SGL increased by 204% (1,291 km2); and 4) the mean size of forest patches decreased from 15.6 to 5.4 km2. In addition, the area of SGL is positively correlated to local human population (R2 0.53), implying that the reduction and fragmentation of habitat for Rhinopithecus bieti is a result of population growth of humans, who mostly employ traditional modes of production. Only 11 monkey groups remained in the changing habitat. Considering that forests at lower elevation were also encroached upon by farmlands in a similar way, the forest ecosystem is highly threatened. The destruction will continue unless there is a change in the mode of production in the region. 相似文献
3.
To effectively conserve sour orange (Citrus aurantium L.) germplasm on two islands at the estuary of the Yangtze River in China, we estimated genetic variation and relationships of the known parental trees and their proposed descendents (young trees) using the fingerprints of random amplified polymorphic DNA (RAPD). Results based on RAPD analyses showed considerable genetic diversity in the parental populations (He = 0.202). The overall populations including the parental and young trees showed slightly higher genetic diversity (He = 0.298) than the parents, with about 10% variation between populations. An unweighted pair group method with arithmetic mean analysis dendrogram based on cluster analysis of the Jaccard similarity among individuals demonstrated a more complicated relationship of the parental and young trees from the two islands, although the young trees showed a clear association with parental trees. This indicates a significant contribution of parental trees in establishing the sour orange populations on the two islands. According to farmers' knowledge, conservation of only one or two parental trees would be sufficient because they believed that the whole populations were generated from a single mother tree. However, this study suggests that preserving most parental trees and some selected young trees with distant genetic relationships should be an effective conservation strategy for sour orange germplasm on the two islands. 相似文献
4.
Rui-Chang Quan Yong Huang Matthew W. Warren Qi-Kun Zhao Guopeng Ren Sheng Huo Yongcheng Long Jianguo Zhu 《International journal of primatology》2011,32(5):1190-1202
Human impacts on the environment at local or regional scales largely depend on intrinsic characteristics of the population,
such as household size, household number, and human population growth. These demographic factors can vary considerably among
ethnic groups sharing similar ecological landscapes, yet the role of traditional cultural practices in shaping local environmental
impacts is not well known for many parts of the world. We here quantify land-cover changes and their relation to the habitat
of the endangered Rhinopithecus bieti in Tibet, in 2 areas populated by different ethnic groups (polyandrous Tibetans and monogamous Naxi) from 1986 to 2006. Results
indicate that habitat of the monkey decreased greatly within our study area over the 20-yr period. Polyandrous and monogamous
ethnic communities differed in household size, household number, population growth, and per capita and per household land
use. The practice of polyandry by ethnic Tibetan appears to have reduced per capita resource consumption by reducing the growth
of overall household number and increasing household size, which can mitigate the negative effects of higher human density
and population growth on the environment. Ethnic Tibetan may also reduce land impacts by adhering to Buddhist customs and
alternative, more sustainable means of livelihood. Accordingly, the protection of traditional cultural resources, such as
polyandry and Buddhist beliefs, could be an effective way to aid biodiversity and environmental conservation efforts in this
key ecosystem. 相似文献
5.
粗糙沼虾精子的超微结构研究 总被引:2,自引:1,他引:2
利用电镜及细胞化学方法,研究了粗糙沼虾(Macrobrachium asperulum)精子的形态和超微结构。结果表明:精子无鞭毛、不运动,由后主体部、中间帽状体和前端棘突组成。主体部呈浅状,内有非浓缩的核,核内含有许多泡囊造近帽状体的核部,分布着许多膜本,膜层体与帽状体紧密相连。棘突具有间隔约31nm的珏纹。环纹由直径为4~6nm的丝状体组成并与环纹相垂直。精子无明显的顶体区。 相似文献
6.
7.
新生隐球菌是自然界广泛存在的具荚膜的酵母型病原真菌,能侵染人类中枢神经系统引起真菌性脑膜炎,每年导致全球大约18万人死亡。本研究在前期隐球菌交配表达谱的基础上,选择一上调表达的RNA结合蛋白基因(CNAG_04772),进行克隆和功能分析。结果表明该基因全长2 247bp,cDNA全长1 518bp,编码505个氨基酸组成的蛋白,含有2个RNA识别基序RRM1和RRM2,命名为RBP1。基因表达模式分析表明RBP1在隐球菌酵母细胞、担子以及担孢子阶段都有表达,交配菌丝阶段不表达;亚细胞定位分析表明Rbp1蛋白定位于隐球菌的细胞核和细胞质中。与野生型菌株H99相比,敲除突变体菌株能够交配并产生双核菌丝,但丧失产生担孢子的能力,而互补菌株与野生型菌株H99间无显著差异。致病力测定结果显示,敲除突变体菌株致病性显著降低。 相似文献
8.
Male-infant-male interactions in Tibetan macaques 总被引:1,自引:0,他引:1
Qi-Kun Zhao 《Primates; journal of primatology》1996,37(2):135-143
Event-sampling and scans were used for collecting data on male-infant-male triadic interactions, and their effects on member
spacing respectively in a group ofMacaca thibetana at Mt. Emei in 1989. The group was partially provisioned by human visitors in seasons other than winter, and could be observed
closely. In addition, a stable linear male-hierarchy among five males existed for two years since the end of 1987, providing
a good social condition for this topic. The triadic interactions were specific to the birth season, and recognized as three
types being on a continuum functionally changing from passive “agonistic buffering” (4.8%) to active spatial cohesion, which
resulted in a significant decline of intermale distances. Positive correlations were documented between the triad initiation
rate and the number of females in consort with the males in the mating season (MS), and between the triad reception rate and
the number of infants in proximity to the males in the MS when maternal care was significantly reduced. Thus the male's mating
effort and kin/sexual selection may deeply be involved in the triad of this species. Considering that the two triad-species,M. sylvanus andM. thibetana, had different levels of paternity, but shared similar foraging conditions, and showed similar intensities of male-infant
caretaking, the triad was very likely a by-product of male-infant caretaking, which was probably shaped to compensate heavy
maternal investment to young offspring in harsh conditions. Accordingly, the long-term arguments about the triad inM. sylvanus can be united to a model of the way in which “male-infant caretaking” hypothesis works ultimately, and “regulating social
relations” hypothesis does proximately. 相似文献
9.
To effectively conserve sour orange (Citrus aurantium L.) germplasm on two Islands at the estuary of the Yangtze River In China, we estimated genetic variation and relationships of the known parental trees and their proposed descendents (young trees) using the fingerprinta of random amplified polymorphic DHA (RAPD). Results based on RAPD analyses showed considerable genetic diversity In the parental populations (H<,e> = 0.202). The overall populations including the parental and young trees showed slightly higher genetic diversity (H<,e> = 0.298) than the parents, with about 10% variation between populations. An unweighted pair group method with arithmetic mean analysis dendrogram based on cluster analysis of the Jaccard similarity among individuals demonstrated a more complicated relationship of the parental and young trees from the two islands, although the young trees showed a clear association with parental trees. This indicates a slgnificant contribution of parental trees in establishing the sour orange populations on the two islands. According to farmers' knowledge, conservation of only one or two parental trees would be sufficient because they believed that the whole populations were generated from a single mother tree. However, this study suggests that preserving most parental trees and some selected young trees with distant genetic relationships should be an effective conservation strategy for sour orange germplasm on the two islands. 相似文献
10.
Qi-Kun Zhao 《Primates; journal of primatology》1994,35(1):57-68
In five groups of seasonally provisioned Tibetan macaques (Macaca thibetana) at Mt. Emei, males were sampled for wounds as an indicator of their competition for females during about 80 days in the
1987 mating season. Quantitative data on intergroup transfer were collected in a period between June 1986 and December 1987.
The young adult (YA) males, the most active age-class in mating activity and intergroup transfer, received most of the wounds.
Wounds tended to appear more in the front of body for YA and subadults (SA) than they did for middle-old aged (MO) males.
This implies that some of the MO males were more active and aggressive in the fights. During the 1.5 year period, 5/6 of the
YA and 5/17 of the MO males made intergroup shifts. Although YA males faced a high risk of receiving wounds at transfer, they
usually rose in rank. On the other hand, the MO males transferred more smoothly but dropped in rank. The peripheral SA males,
which rarely emigrated in the population, were an active component in determining the wounding rate, and the rate and direction
of male migration. Three SA immigrants died of severe attacks made by resident males in 1988 and 1991. Adult sex ratios and
their variations were considerably reduced with male nonrandom shifts and better conservation of the population. 相似文献