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1.
厦门白鹭自然保护区的白鹭繁殖行为和繁殖力研究   总被引:8,自引:4,他引:8  
2 0 0 1年 3月至 7月对厦门白鹭自然保护区鸡屿岛的白鹭 (Egrettagarzetta)繁殖行为和繁殖力进行了研究 .白鹭集群、择巢、筑巢于 2月中旬至 3月中旬 ,3月底部分亲鸟开始产卵和孵化 ,4月中旬雏鸟开始出壳 .白鹭窝卵数为 4.43± 0 .6 8(SD)枚 ,孵化期为 2 3.2± 1.4d ,孵化率为 88.5 0 % ,窝雏数为 3.8± 0 .8只 ,育雏期 2 8~ 35d ,雏鸟成活率为 87.7% .每年每只白鹭的繁殖力为 1.96只雏鸟 ,每巢成功繁殖 3.37只雏鸟 .鸡屿岛白鹭繁殖前期的种群数量为 5 0 32只 ,繁殖结束时亲鸟和成活雏鸟数量共 135 0 6只 .本文分析影响白鹭繁殖的主要因素 ,并提出白鹭繁殖期的管理和保护措施  相似文献   

2.
2003年6月在厦门大兔屿鹭类营巢地首次发现暗色型白鹭,对其形态、繁殖以及子代雏鸟进行研究.暗色型白鹭在厦门的数量稀少,其羽色为暗灰色,但在头、喉、胸或腹部上存在着不同程度的白羽差异.暗色型白鹭与白色型白鹭结对繁殖,共同完成孵卵和育雏过程.暗色型白鹭巢位高度为520cm,较同一树上其他4个白鹭的巢位(428±62)cm高,巢高21.2cm,巢深10.8cm,巢内径38.0cm,巢外径60.2cm;卵呈鸭蛋青色,卵的长径为3.33cm,短径4.52cm,质量23g;窝雏数为4只;1日龄雏鸟平均体长(10.8±0.2)cm,平均体质量(21±0.5)g,子代雏鸟的羽色为白色,喙表现为乌黑发亮,皮肤颜色也较白色型黑.暗色型白鹭亲鸟和雏鸟的繁殖及生长发育等其它生物学特性与白色型白鹭基本相同.本文对国内暗色型白鹭的来源及其羽毛颜色的遗传特性进行分析探讨.  相似文献   

3.
文章报道了小云雀inopinata亚种(Alauda gulgula inopinata)(以下称为小云雀亚种)在西藏拉萨地区的繁殖生态。小云雀亚种在拉萨地区一般4月下旬进入繁殖期,选择本地的冬小麦地等作为它们的繁殖生境。雌雄鸟均参加筑巢,筑巢期为3.8±1d(n=4),10个巢的大小为5.6±0.7cm×8.7±0.9cm(n=10),巢深4.1±0.3cm(n=10),巢的平均重量24.6±4.3g(n=5)。平均窝卵数为2.6±0.5枚(2~3枚,n=7),其中3枚者居多;产一窝卵需要2~3d,卵平均重量2.2±0.3g(1.8~2.8g,n=7),卵的大小为20.4±0.5mm(19~21)×14.2±3mm(14~15),(n=7)。平均孵卵期为15±0.6d(14~16,n=6),孵化率为67%,育雏期12±0.6d(11~13,n=6),雏鸟成活率仅50%。农业活动及天敌是影响孵化率及雏鸟成活率的主要因子。  相似文献   

4.
郑州鹭类的生态习性   总被引:9,自引:0,他引:9  
1999~2003年对河南郑州市区鹭鸟的生态习性进行了研究。结果表明:郑州市区共有夜鹭(Nycticoraxnycticorax)、池鹭(Ardeolabacchus)、白鹭(Egrettagarzetta)及苍鹭(Ardeacinerea)4种鹭鸟营巢繁殖,栖息地道路总长4600m,道路面积约132400m2。2003年栖息地共有鹭巢6762个,巢密度为0.051个/m2。平均每株行道树有鹭巢12.47个,多的超过30个。鹭类对营巢树的利用具有选择性。从种群数量上看,夜鹭占绝对优势,占98.05%,其次是池鹭,白鹭和苍鹭数量较少。据2003年统计,在市区停留的时间为:夜鹭212天,池鹭158天,白鹭147天。雏鸟留巢期为夜鹭49.17±0.835天,池鹭32.7±1.059天,白鹭41.43±1.134天,均较荒野地长。平均出雏数为:夜鹭2.85±1.268只,池鹭4.50±1.35只,白鹭4.43±1.27只。鹭鸟在市区繁殖是人类活动影响的结果,并对市区环境造成一定的影响。  相似文献   

5.
1996年乌鸫开始栖息于新乡地区,成为当地留鸟,但其繁殖状况并不清楚.为了弄清该地区乌鸫的繁殖生态,2017年3~7月,采用定位观察法,对新乡黄河湿地鸟类国家级自然保护区乌鸫的繁殖生态及巢址选择进行了详细研究,结果表明:新乡乌鸫3月初进入发情期,3月中旬可见到乌鸫配对,具有明显的占区行为.3月下旬开始营巢,营巢任务由雌鸟承担,营巢需时4~10d.最早产卵是3月28日,最晚产卵是5月16日,窝卵数为(5.09±0.70)(n=11)枚,产卵期为一周.卵长径(31.16±2.06)mm,卵短径(23.11±0.68)mm,卵质量(6.73±0.85)g.孵化期为13~14d,由雌鸟承担,孵化率为85.71%.育雏期为13~15d,成活率为54.17%.  相似文献   

6.
对黑枕黄鹂的分布和数量、迁徙及活动规律、繁殖习性作了全面系统的报道.黑枕黄鹂分布于海拔800m以下的低山阔叶林中,在海拔300m的次生阔叶林中种群数量较大,为典型的低山带鸟类.春季迁来时间一般在5月中旬,8月中下旬迁出.主要在阔叶林中的阔叶树上营巢.巢位选择过程中,巢址多在树冠下层的外侧,巢筑在离树干较远的侧枝水平枝权间.营巢期6~7d.窝卵数为3~5枚.雏鸟一般13.5d离巢.雏鸟生长方程为:W=59.1/1 e^-0.613(t-1.994).  相似文献   

7.
1988年3—8月在陕西省勉县铜钱坝乡陈家湾村对苍鹭的繁殖生态进行了观察。结果表明;苍鹭营巢期3~7天,交尾后5~7天产第一枚卵,窝卵数4.27±1.44(n=15)枚,孵化期25~27天,卵的重量损失率为16.6±4.4%(n=23)。雏留巢期约40天,育雏期60天。营巢、孵化、育雏均由双亲共同承担。  相似文献   

8.
红腹角雉(Tragopan temminckii)的孵卵和育雏行为研究   总被引:2,自引:0,他引:2  
于2005年4-7月、2006年3-7月,采用焦点动物取样法和所有事件取样法对四川老君山自然保护区红腹角雉(Tragopan temminckii)的孵卵和育雏行为进行了研究.对3个孵化期内的树上巢分别观察16、5和9 d,记录到典型行为8种.观察的时段包括孵卵中期、孵卵后期和巢内育雏期.孵卵中、后期以出雏前7 d为界,中、后期之间的行为频次和累计时间均存在明显差异.Spearman秩相关检验显示翻卵日频次和日翻卵时间与观察时间呈极显著正相关(P<0.01).离巢时间和平均气温存在极显著正相关(P<0.01).孵卵期间日离巢0~2次,通常在上午和傍晚离巢,离巢平均时间(27.6 ± 4.4) min (n=29).离巢率孵化中期为4.86%,孵化后期为5.37%.雏鸟在巢期间为(3754.5±42.5) min (n=2),此期雌鸟不离巢,行为复杂.  相似文献   

9.
2002~2004年,在蟒河自然保护区对北红尾鸲的繁殖习性进行了观察.结果表明。该鸟每年3月上旬迁入该区。10月下旬迁离.3月下旬营巢.4月中旬产卵,窝卵数3~6枚.孵化期12~13天。孵化率为90%.巢内育雏期12天.巢外育幼期约10天.在该区全年的种群密度为4.41只/km^2.  相似文献   

10.
黑翅鸢(Elanuscaeruleus)近年来在福建省的分布范围逐渐扩大,在福建省南部和东部为留鸟.对黑翅鸢的繁殖生态学研究结果说明,黑翅鸢繁殖期从4月~12月,筑巢对树种具有一定的选择性,每次繁殖都要重新筑巢,主要巢材为枯树枝,巢离地高度都在11m以上(n=4),巢外径为40cm,巢高30cm,巢深10cm(n=1).黑翅鸢每窝繁殖雏鸟3~4只,离巢时的雏鸟成活率都达到100%(n=4).繁殖期的黑翅鸢食物主要为鼠类.黑翅鸢的繁殖期长,繁殖力强,雏鸟成活率高,对人类活动环境的适应能力强,这可能是近年来黑翅鸢分布范围能够扩大的主要原因.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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