赤腹鹰巢址选择和繁殖成效的影响因子分析

【目的】通过调查赤腹鹰的巢址特征、巢防卫行为和繁殖结果,分析赤腹鹰的巢址选择机制和繁殖成效,揭示影响赤腹鹰繁殖成效的主要因子,为其保护工作提出建议。【方法】根据赤腹鹰巢防卫行为的不同强度,将其分为4个巢防卫等级,并记录10 min内的鸣叫次数;收集巢址参数,包括树种、巢离地高度、胸径、海拔、树冠面积、坡位、坡度、坡向、巢前方视角、巢距道路距离、巢距房屋距离、巢距水源距离、半径20 m样圆内的植被特征。用SPSS对数据进行分析。【结果】2016和2017两年的5—8月,共发现赤腹鹰繁殖巢51个,对其中35个巢进行红外相机监控,累计拍摄监控照片661 306张。其中,2016年赤腹鹰的孵化率为71. 4%(n=77枚),雏鸟存活率为78. 2%(n=55只); 2017年的孵化率为82. 5%(n=63枚),雏鸟存活率为61. 5%(n=52只)。通过检查红外相机中的监控照片发现,赤腹鹰繁殖失败的主要原因在于卵或者雏鸟被捕食,捕食者包括王锦蛇(n=9巢)、松鸦(n=1巢)和黄鼬(n=1巢)、凤头鹰(n=1巢)。巢树与道路的距离越远,雄鸟的鸣叫次数越多(r=0. 68,n=12,P 0. 05,Spearman),雌鸟的巢防卫等级就越高(r=0. 42,n=42,P 0. 01,Spearman)。雏鸟存活率与巢树到道路(r=-0. 45,n=47,P 0. 01,Pearson)的距离呈显著性负相关,与巢树胸径、离地高度、巢树和房屋或农田之间的距离、雌雄鸟的巢防卫行为、样圆内植被参数之间的相关性都不显著。巢树离房屋(r=-0. 56,n=47,P 0. 01,Pearson)和道路(r=-0. 35,n=47,P 0. 05,Pearson)越近,巢的离地高度越高。对巢离地高度(y,m)和巢树到房屋的距离(x,m)进行线性回归分析,得到y=12. 75-0. 01x(R2=0. 32,n=47,P 0. 01)。主成分分析共筛选出8个主成分,巢树大小与生境中乔木林的质量对赤腹鹰巢址选择起着重要作用,人类活动区和水源起着次要作用。【结论】赤腹鹰倾向于选择远离人类活动区的区域营巢,但随着对人类活动的适应,靠近公路筑巢的赤腹鹰会有更高雏鸟存活率;巢防卫行为强的赤腹鹰更偏好距离人类活动区远的巢址;巢址靠近人类活动区的赤腹鹰会选择在更高的位置筑巢;赤腹鹰通常在靠近水源、乔木种类丰富、枝叶茂密,但灌木和草本较为稀疏的树林中营巢,巢树一般高大粗壮。     

昆明动物园野生小白鹭营巢高度选择与营巢材料研究

对昆明动物园内干香柏树上营巢的野生小白鹭进行研究,测算其最低适宜营巢枝干和实际最低营巢枝干占树高的百分比,并检测两者的差异显著性。结果表明,实际营巢高度与适宜营巢高度占树高百分比存在显著差异,可能因为亲鸟为避免来自地面的干扰,选择离地较高的位置繁育后代。通过分析坠落鸟巢的构成材料,发现其由268根植物枝条构成,其中91%为干香柏,与主要营巢树一致,说明此地可能由于提供丰富的营巢材料而被鹭群选择成为繁殖地。建议公园积极加强野生涉禽的科学管理,降低繁殖区内及周边的干扰。     

基于3S技术的扎龙湿地丹顶鹤巢址选择模型

利用遥感、地理信息系统和全球定位系统技术,对黑龙江扎龙国家级自然保护区丹顶鹤巢址选择的"出现点"和"非出现点"初选变量进行空间自相关性检验,采用二项逻辑斯蒂克模型进行回归建模.结果表明:影响丹顶鹤巢址选择的自然环境因子包括芦苇高度、盖度和高程,干扰因子包括巢址距居民点距离、巢址周边堤坝和道路密度网.经计算预测值与观测值之间的匹配系数来验证模型准确性,总正确预测率为80.4%.将土地利用图与模型预测概率图进行叠加分析,得出扎龙湿地丹顶鹤适宜营巢栖息地的面积为223.46 km2,主要分布在保护区的中部和北部.模型的预测结果基本反映扎龙湿地丹顶鹤适宜营巢栖息地的分布情况,为开展营巢地的有效保护与管理,并针对性地恢复重要营巢地提供科学依据.     

2001年大火对扎龙自然保护区丹顶鹤栖息与繁殖的影响

2001年8月末至10月扎龙自然保护区发生重大火灾，大火虽对保护区丹项鹤(Grus japonensis)的栖息地有一些影响，但对整个保护区丹项鹤的迁徙数量影响不大；对丹项鹤的营巢环境、巢址选择、巢材等因子产生较大影响，巢周围剩余芦苇面积、高度成为丹项鹤巢址选择的主要因子，次要因子是植被类型；大火对丹项鹤的始营巢期产生了影响，其营巢期较正常年份延缓4～5天。     

射阳县林场鹭巢调查初报

射阳县林场属江苏盐城国家级珍禽自然保护区缓冲区范围。经调查,在29.33 hm2水杉林内,统计到牛背鹭、池鹭、夜鹭、中白鹭、白鹭5种鸟集群营巢数达11 996.8个,高密度区域每株水杉营巢数为3个;巢位距地面高因树的高度而异,分别为90~100,110~125,130~140 cm。外围优越的生态环境为其高密度集群营巢创造了有利条件。     

鸭绿江下游鹭类集群繁殖地新发现

鸭绿江下游现有两处鹭类集群繁殖地,栖息有10种鹭类。2009年5月于辽宁省东港市北井子镇范家山新发现一处鹭类集群繁殖地,繁殖鹭类6种:夜鹭、白鹭、大白鹭、牛背鹭,数量较多;其次为池鹭,20只左右;苍鹭较少。巢1 820个,巢树16种,营巢树1 025株。     

长青保护区血雉繁殖期密度与巢穴利用调查

长青保护区血雉分布的中心区域是兴隆岭地区,分布面积约4 000 hm^2。分布区的最高海拔3 000 m、最低海拔2 300 m。为了掌握血雉种群和人为干扰现状,提高保护管理水平。利用样带法、跟踪调查法,调查血雉的种群密度与巢穴利用情况。得出血雉平均密度0.2171只/hm^2,种群数量为868只。血雉不利用旧巢穴,当年选择巢址,产卵数最大为8枚,有弃巢现象,但是能适应一些自然因素的干扰。血雉种群分布区和密度稳定,处于稳定期。     

昆明市呈贡区回回营社区野生鹭鸟集群营巢情况调查

2019年至2021年对云南省昆明市呈贡回回营社区混合集群的鹭鸟开展调研,分别于2019年10月, 2021年4、5、6月对鹭群进行4次访问。2019年10月,鹭鸟繁殖栖息地主要由竹子和少量桉树构成,地面覆盖大量落叶;其间污水流淌,形成数条小河和一个池塘。2021年统计每棵竹子和桉树上鹭巢数量及营巢鹭鸟种类,并测量巢距离地面的垂直高度。该地发现有小白鹭、黑顶夜鹭和牛背鹭筑巢繁殖,其中小白鹭和黑顶夜鹭构成群落数量主体。2021年4月记录21个鹭巢（小白鹭与黑顶夜鹭）,5月记录41个鹭巢（小白鹭、黑顶夜鹭和牛背鹭;此月为繁殖高峰）,6月记录8个鹭巢。鹭巢距离地面平均距离为8.78 m。目前,该鹭群由于回回营面临拆迁而受到威胁,为此提议保留鹭群所在的繁殖地,并改善研究地点及周边地区水质情况。     

白腰鹊鸲的繁殖生态研究

指出了白腰鹊鸲是广泛分布于南亚和东南亚的雀形目鸣禽,其鸣声清脆悦耳,但目前中国还没有关于白腰鹊鸲的繁殖生态学研究。白腰鹊鸲繁殖期间是利用已有洞资源来筑巢的次级洞巢鸟,通过放置人工竹筒巢及繁殖期的观察,对白腰鹊鸲的巢址选择、窝卵数、卵情况、繁殖失败因素等进行了调查研究。结果表明:白腰鹊鸲的繁殖季为每年的3月下旬到7月下旬,繁殖高峰期为4~6月份;白腰鹊鸲窝卵数一般为4枚,单枚卵重3.18±0.27g;白腰鹊鸲一个完整的育雏周期为26±2 d,其中孵化周期为15±1 d,育雏周期为11±3 d。巢材的植物包括14科18属20种,主要营巢材料包括羽叶金合欢(Acacia pennata)、托叶黄檀(Dalbergia stipulacea)、铁刀木(Senna siamea)。巢址距道路最近距离为20.72±16.34 m,距离房屋最近距离为31.29±19.11 m,巢高为1.27±0.4 m。白腰鹊鸲巢失败的主要因素为巢被捕食。     

历山自然保护区30种鸟类繁殖特性及成效的研究

１９９３年—１９９７年的４月—９月，对山西省沁水县中村地区，３０种鸟类的自然繁殖特性及成效进行了观测研究。５年共观测到营巢成功巢１５０窝，产卵成功巢１０７窝，离巢成功巢８６窝，巢外育幼成功巢５６窝，成功率分别为８３．８０％，７１．３３％，８０．３０％和６５．１１％。影响鸟类繁殖成效的主要因素是人为活动的干扰。     

大屏嶂森林公园次生常绿阔叶林树木的构筑型特征分析

文章采用网格取样技术结合线路调查法,在大屏嶂森林公园次生常绿阔叶林内设置9个样地,对样地内共26个树种的乔木立木进行调查,并且初步分析构筑型特征。研究结果显示：（1）树木冠形主要有卵形、圆球形、圆柱形、伞形和圆锥形5种基本类型,以圆球形冠形的树木种类比例最高,占统计总数的30％;（2）乔木冠幅多数属于中冠幅类型,并存在较小的分枝角度,其中以45°的比例最高,达到30．8％,其次是30°,占23．1％;（3）树木的分枝级数最大为7级,而以4级分枝的树种最多,占统计总数的38．5％;（4）树高与枝下高以及胸径的关系均符合幂函数关系,并且均呈正相关。     

Eight hundred years of clonal forestry in China: II. mass production of rooted cuttings of Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.)

Since 1986 a novel type of shoot orchard has been under development. Lower portions of the donor stems are buried horizontally in the soil and cuttings are taken from shoots that arise from them. This process apparently rejuvenates, so that mature trees of various ages can be propagated vegetatively. Seedlings of superior provenances, open-pollinated, and control-pollinated families, stump sprouts and upper branches of plus trees were used to establish the orchard, which contains about 40,000 donors and occupies 1.3 ha. Cuttings produced in this orchard can be rooted to about 85% success without hormones or shading. This shoot orchard provides more planting stock, and provides it five to six years earlier, than a seed orchard. The height and root-collar diameter of the rooted cuttings are greater than those of seedlings at outplant, and production costs are 15–20% lower than those associated with seedling production. Test plantations demonstrated that four-year height and diameter of cuttings and genetically similar seedlings are equivalent. This paper reports the details of this orchard, and summarizes other work on propagation and storage of Chinese fir cuttings.     

不同强度人为干扰对马尾松生长的影响

不同强度人为干扰15a后,经解析木分析表明,轻度干扰林分中马尾松的胸径、树高、材积均保持良好的生长趋势,总生长量比中度干扰和重度干扰林分高,连年生长量和平均生长量在幼龄期也高于后二者,重度干扰林分的各要素生长量均增长缓慢。这些结果表明超过一定限度的人为干扰阻碍了林木的生长发育。     

Height growth recovery and crown development in top‐damaged Pinus sylvestris trees

Leader shoot damage was imposed on young Scots pines (3 m high) in four ways: by caging the uppermost whorl including the leader shoot with 10 pine shoot beetles; by caging the two uppermost whorls with 20 beetles; by topping the tree below the 1984 whorl; by topping the trees as above and removing all current shoots in whorl 1983. Six years later, top‐damaged trees were still significantly shorter than undamaged controls, although the annual height growth rate had recovered to the pre‐damage level within 3 years. Recovery occurred in two ways: lateral branches from the nearest intact whorl took dominance over the damaged leader or secondary branches developed from interfascicular buds on the damaged leader shoot. Approximately one and two years of height growth were lost in the former and latter case, respectively. Only 5 of the 34 top‐damaged trees escaped technical defects (crooks and/or vertical branches). Stem diameter and crown development were slightly affected.     

昆明世博园福建生态园园林植物群落结构

对昆明世界园艺博览园福建生态园的园林植物群落进行物种结构、水平结构、垂直结构和季相的研究。生态园共有植物23种,分属于17科,22属;园林植物水平配置以自然式为主;园林树木胸径都集中在20cm以下,冠幅都在4m以下;乔、灌、花草成层形成典型的园林植物群落垂直结构,树高集中在3~6.5m范围;园林植物群落外貌四季变化不明显。     

保定市环城路绿地植物群落结构分析

为了认识保定市环城路绿地绿化结构特征,进而为保定市环城路绿地的建设提供指导和依据,采用抽样调查的方法,对保定环城路的树木进行了每木实地调查,对保定环城路绿地树木的种类组成、高度、径阶等结构特征进行分析.结果表明:15种主要树种占树木总量的60.24%.其中大约71.5%的树木属于小径木(胸径<10 cm),表明保定市环城路绿地绿化总体水平不高,有待改善.     

Impact of artificial pruning on growth and secondary shoot development of wild cherry (Prunus avium L.)

Producing high value veneer wood requires that the tree bole be branch-free. This can be accomplished by natural or artificial pruning. Since wild cherry does not self prune well, pruning artificially is the only practical option. The study analysed the effect of conventional whorl-wise pruning and selective pruning, on height growth, diameter growth and secondary shoot development of wild cherry. Four pruning treatments were applied on cherry trees in summer 2007, one group of cherries was left unpruned to serve as a control: treatment C1 (upper 5 whorls left), C2 (upper 3 whorls left), S1 (removal of branches larger than 3 cm or with an angle to the stem < 40°), S2 (removal of branches larger than 2 cm or with an angle to the stem < 40°), N (unpruned). Data showed that height growth was not affected by pruning. In contrast, diameter growth at breast height of the C2 pruned cherry was reduced by approximately 5% (SE = 2.7%) in the year of pruning (trees were pruned in July). This pruning treatment produced significant (p = 0.028) nine percent less diameter growth than the control in the second year following pruning. The diameter increment of the C1 pruned trees with five whorls left after pruning and the selective pruned cherries were only about 4% (SE = 4.0%) smaller than the control after two years. This loss was statistically not significant. Analyses showed that on selective pruned trees the survival rate of secondary shoots was significantly reduced compared to those on whorl-wise pruned trees. Significant differences in the size of the secondary shoots were only found between the C1 and S1 (p < 0.05) pruned trees. We did not find differences in the total number of secondary shoots per tree among pruning treatments. Solely from a tree growth perspective, the moderate whorl-wise pruning treatment C1 and the selective prunings were equally effective in minimizing the reduction of diameter growth and are recommended in practice. However it was found that the survival of secondary shoots was reduced on selective pruned trees although the amount of pruning work needed in selective pruning was slightly greater than conventional moderate pruning.     

Secondary forest floristic composition, structure, and spatial pattern in subtropical China

Secondary evergreen broadleaved forests are precious remnants for biodiversity conservation and templates for sustainable management of natural forests in subtropical China. Floristic composition, size structure, and spatial pattern of dominant tree species have been investigated for a subtropical secondary evergreen broadleaved forest in the Huitong Yingzuijie National Forest Reserve, Hunan, China. The location of all trees greater than 4 cm in diameter at breast height (DBH) were mapped within a 0.96-ha plot in which species, DBH, and total tree height were recorded. Ripley’s K(t) function was used to analyze spatial patterns and associations. The secondary forest consisted of 74 tree species and 1,596 stems per hectare. A reverse-J shaped DBH classes distribution was observed for all stems and trees of later seral species whereas trees of earlier successional species were distributed irregularly. Significant aggregated spatial patterns were observed for all trees within the forest and for conspecific trees of each dominant species. This result, and a repulsive spatial pattern for interspecific trees of Choerospondias axillaries and Cyclobalanopsis glauca against other dominant tree species, support segregation hypothesis. Contributions of seed dispersal, topographic heterogeneity, and competition to spatial patterns of conspecific trees vary depending on tree species. Attractive spatial pattern among interspecific trees of Liquidambar fortunei, Liquidambar formosana, and Pinus massoniana reflects stochastic colonization of pioneer tree species and a facilitation relationship. Although deciduous species are long-lived and persist over long successional processes, they will eventually be replaced by late seral evergreen species within the secondary forest if no disturbance events occur.     

Growth response and sapwood hydraulic properties of young lodgepole pine following repeated fertilization

We examined how tree growth and hydraulic properties of branches and boles are influenced by periodic (about 6 years) and annual fertilization in two juvenile lodgepole pine (Pinus contorta Dougl. var. latifolia Engelm.) stands in the interior of British Columbia, Canada. Mean basal area (BA), diameter at breast height (DBH) and height increments and percent earlywood and sapwood hydraulic parameters of branches and boles were measured 7 or 8 years after the initial treatments at Sheridan Creek and Kenneth Creek. At Sheridan Creek, fertilization significantly increased BA and DBH increments, but had no effect on height increment. At Kenneth Creek, fertilization increased BA, but fertilized trees had significantly lower height increments than control trees. Sapwood permeability was greater in lower branches of repeatedly fertilized trees than in those of control trees. Sapwood permeabilities of the lower branches of trees in the control, periodic and annual treatments were 0.24 x 10(-12), 0.35 x 10(-12) and 0.45 x 10(-12) m2 at Kenneth Creek; and 0.41 x 10(-12), 0.54 x 10(-12) and 0.65 x 10(-12) m2 at Sheridan Creek, respectively. Annual fertilization tended to increase leaf specific conductivities and Huber values of the lower branches of trees at both study sites. We conclude that, in trees fertilized annually, the higher flow capacity of lower branches may reduce the availability of water to support annual growth of the leader and upper branches.