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101.
2000年3月至5月,在上海野生动物园人工饲养状态下对83只松鼠猴的行为时间分配进行了研究,以间隔20分钟用随机取样法记录松鼠猴的各种行为及其频次,通过211小时的观察研究表明,松鼠猴最主要的个体4行为有跑动,攀爬,取食,休息,嬉戏,它们分别占到日活动时间的13.55%,16.15%,24.46%,33.21%,8.18%,其次,成年雌、雄松鼠猴之间的挨近行为也占了松鼠猴日活动时间的4.46%,松鼠猴晨昏活动规律十分明显(F=12.575,P=0.00006),其活动行为(除去休息之外的所有其他行为)的高峰出现在5:00-6:00、15:00-16:00左右的两个时段,峰值分别为76.61%-76.79%,75.87%-83.59%,日活动时间从5:00至19:30左右,持续约860分钟。 相似文献
102.
The downstream migration of Atlantic salmon (Salmo salarL.) and sea trout smolt (S. trutta L.) was investigated using radio telemetry in the spring of 1999 and 2000. Forty wild sea trout smolts, 20 F1 sea trout smolts, 20 hatchery salmon smolts and 20 salmon smolts from river stockings were radio tagged and released in the Danish River Lilleaa. The downstream migration of the different groups of fish was monitored by manual tracking and by three automatic listening stations. The downstream migration of radio tagged smolts of both species occurred concurrently with their untagged counterparts. The diel migration pattern of the radio tagged smolts was predominantly nocturnal in both species. Wild sea trout smolt migrated significantly faster than both the F1 trout and the introduced salmon. There was no correlation between net ground speed, gill Na+,K+-ATPase activity or fish length in any of the different groups. The migration speed of wild sea trout smolts was positively correlated with water discharge in both years. In F1 sea trout smolts, migration speed was positively correlated with temperature in 1999. The migration speed of salmon smolts did not correlate to any of the investigated parameters. 相似文献
103.
Prietzel Jörg Weick Corry Korintenberg Julia Seybold Gabriele Thumerer Thomas Treml Bernd 《Plant and Soil》2001,230(2):287-305
The effect of repeated (NH4)2SO4 applications (3 × 700 kg ha–1 in 1988, 1991, and 1994, respectively) on S pools in soil, soil microbial biomass, and ground vegetation was studied at two Norway spruce (Picea abies L. [Karst.]) sites in the Black Forest/Germany. In both eco-systems, most of the total S pool was located in the soil. The soil also was the predominant compartment for retention of applied SO4
2--S. The fractions of organic and inorganic S forms in the initial soil S content, and the retention of experimentally applied S was different for both sites. In the podzol Schluchsee, organic S accounted for 92% of total S. In the cambisol Villingen, the S pool consisted of 33% organic S and 67% inorganic S. The retention of applied S in various compartments of both ecosystems reflected these proportions. Only minor amounts of fertilized S (<1%) was retained in the spruce trees, ground vegetation, and soil microbial biomass. However, between 51% (Villingen) and 72% (Schluchsee) of the applied S was retained in the soil. In the Schluchsee podzol, 75% of retained fertilizer S was accumulated as ester sulfate, whereas SO4
2-adsorption and precipitation of Al hydroxy sulfates were restricted by dissolved organic matter in the soil solution. In the Villingen cambisol, SO4
2- adsorption was the dominant process of S retention, although 20% of the fertilized S again was retained as ester sulfate. The significant relevance of organic S forms in the retention of fertilizer S in both soils emphasizes the need for models which include the formation and re-mineralization of organic S compounds, especially of ester sulfates, for correctly simulating and predicting the retention and remobilization of S in acid forest soils subject to changing atmospheric N and S deposition. 相似文献
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105.
C. Brouat G. Mondor‐Genson P. Audiot F. Sennedot L. Lesobre J.‐Y. Rasplus 《Molecular ecology resources》2002,2(2):119-120
We isolated and characterized 10 microsatellite loci in the ground beetle Carabus nemoralis (Coleoptera, Carabidae), an ubiquist species largely distributed in Europe. Polymorphism ranged from 3 to 12 alleles on the 30 individuals from the same locality examined. 相似文献
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107.
Occlusal pattern of cheek teeth in extant Spermophilus: A new approach to the identification of species
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Lilia Popova 《Journal of morphology》2016,277(6):814-825
Discrete characters of the occlusal surface (additional cusps) have been studied to elaborate a new approach to the identification of the Ground Squirrel species Spermophilus odessanus, S. suslicus, S. pygmaeus, S. citellus, and S. xanthoprymnus. Data on the presence/absence of the additional cusps have been represented as star plots and, in addition, have been studied using discriminant function analysis. The species‐specific sets of the characters (patterns of bunodonty) have been revealed and are of high diagnostic value. The Citellus‐set is defined by the presence of mesostyles and the rareness of the metastylids, paraconules and metaconules, hypostyles and protostyles. The Pygmaeus‐set is characterized by the presence of additional cusps in the lower cheek teeth. The Odessanus‐oriented set is found in the Spermophilus pygmaeus, S. odessanus, and S. suslicus. The relatively high frequency of additional cusps of the metaloph and the paraloph is characteristic for this set. The Plesiomorphic‐set (characters shared by all the studied species and for this reason regarded herein as ancestral) is found in S. xanthoprymnus. The patterns of bunodonty serve as diagnostic criteria only as a whole: the shape of a star plot (relations among the character frequencies), rather than certain character values, is indicative. An optimal level of identification of species is possible based on the combination of the discrete characters mentioned and on the size parameters of the third upper molar. The occlusal sets are intended to remain stable during the time of species existence and seem to correspond to trends in specialization. The functional meaning of the sets can be explained by the dependence between the presence/absence of the discrete characters and the shape of the crown and its main lophs. Each pattern is likely to correspond to a trophic niche, and this niche corresponds to the species. J. Morphol. 277:814–825, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
108.
109.
Allison McNamara Noah T. Dunham Liza J. Shapiro Jesse W. Young 《American journal of primatology》2019,81(9)
Wild primates encounter complex matrices of substrates that differ in size, orientation, height, and compliance, and often move on multiple, discontinuous substrates within a single bout of locomotion. Our current understanding of primate gait is limited by artificial laboratory settings in which primate quadrupedal gait has primarily been studied. This study analyzes wild Saimiri sciureus (common squirrel monkey) gait on discontinuous substrates to capture the realistic effects of the complex arboreal habitat on walking kinematics. We collected high‐speed video footage at Tiputini Biodiversity Station, Ecuador between August and October 2017. Overall, the squirrel monkeys used more asymmetrical walking gaits than symmetrical gaits, and specifically asymmetrical lateral sequence walking gaits when moving across discontinuous substrates. When individuals used symmetrical gaits, they used diagonal sequence gaits more than lateral sequence gaits. In addition, individuals were more likely to change their footfall sequence during strides on discontinuous substrates. Squirrel monkeys increased the time lag between touchdowns both of ipsilaterally paired limbs (pair lag) and of the paired forelimbs (forelimb lag) when walking across discontinuous substrates compared to continuous substrates. Results indicate that gait flexibility and the ability to alter footfall patterns during quadrupedal walking may be critical for primates to safely move in their complex arboreal habitats. Notably, wild squirrel monkey quadrupedalism is diverse and flexible with high proportions of asymmetrical walking. Studying kinematics in the wild is critical for understanding the complexity of primate quadrupedalism. 相似文献
110.
The effect of dexamethasone-induced alteration of adrenocortical activity was assessed in two species of New World primates: Saimiri sciureus and Callicebus moloch. Basal and stress levels of corticosteroids were determined following treatment with three doses of dexamethasone (0, 50, or 500 μg/kg). Saimiri showed substantially higher basal levels of corticosteroids than did Callicebus and a greater incremental corticosteroid response to physical restraint. Dexamethasone was found to reduce basal corticosteroids in both species, although this effect was greater for Callicebus than for Saimiri Moreover, the adrenocortical response to physical restraint was reduced by dexamethasone treatment in Callicebus but not in Saimiri. The pattern of results suggests that the species differ in the mechanisms mediating adrenocortical activity. 相似文献