青海省海北地区高寒草甸雀形目鸟类的繁殖生产力

通过对高寒草甸１０种雀形目鸟类繁殖生产力研究表明,高寒草甸鸟类的繁殖生产与鸟类栖息地所处的地理环境、营巢类型和繁殖方式密切相关。其中繁殖季节长度和窝卵数是影响高寒草甸鸟类繁殖生产力的两个最重要的因子（Ｐ〈０．０５）。鸟类平均繁殖生产力为２．８０（只／对．年）。     

高寒草甸几种雀形目鸟类的标准代谢（SMR）

本文在-25℃至40℃的温度范围内,采用开放式呼吸仪测定了高寒草甸5种常见的雀形目留鸟的标准代谢率与环境温度的关系。其基础代谢率(BMR)在3.72—5.69毫升/克/小时范围内,中性温度区下限较低,一般在20℃左右。环境温度在下临界温度以下,代谢率随温度下降而升高的斜线陡峻,斜率一般为0.150—0.170之间。除树麻雀外,在40℃条件下均出现部分死亡。     

7种高寒草甸雀形目鸟类食性与消化道形态的比较

食物是多维生态位理论中最重要的一维,食物生态位的分离对群落中物种的稳定共存起到非常重要的作用。对高寒草甸生态系统中常见的7种雀形目鸟类的食性调查表明,它们主要以草籽、昆虫和燕麦等为食,且不同物种对不同食物的取食比例存在较大差异;不同物种的食物生态位宽度变化较大(0.120~0.752),除黄嘴朱顶雀(Carduelis flavirostris)和地山雀(Pseudopodoces humilis)的食物生态位重叠较小(0.059)外,其他物种间的重叠都较大(0.334~0.904)。不同物种的肝重、胃重和小肠长度存在较大的差异,比如:以草籽为食的黄嘴朱顶雀,其肝重和胃重较小,小肠长度最大;以昆虫为食的地山雀,其胃重和小肠长度最小,肝重较大。随着各物种食性由草籽到昆虫的变化,小肠长度逐渐变小,杂食性物种的相关变化不明显。栖息于相似生境中的雀形目鸟类具有不同的食物资源利用模式,而同域共存物种消化道形态结构的差异是对食物资源利用种间权衡的功能响应。     

高寒草甸常见雀形目鸟类的卵壳特征

作为胚胎发育的屏障,卵壳特征如卵壳厚度和气孔密度具有重要的生态学意义。本文研究了高寒草甸繁殖的7种代表性雀形目鸟类角百灵（Eremophila alpestris）、小云雀（Alauda gulgula）、黄头鹡鸰（Motacilla citreola）、树麻雀（Passer montanus）、粉红胸鹨（Anthus roseatus）、黄嘴朱顶雀（Carduelis flavirostris）、赭红尾鸲（Phoenicurus ochruros）的卵与卵壳特征,以探索在高寒缺氧环境下,不同科鸟类的适应性调节。结果发现,7种鸟类中,除小云雀和角百灵之外,其他鸟类的卵与卵壳特征均有显著的种间差异（除卵壳厚度和气孔直径之外）;对7种鸟类卵壳厚度、气孔密度、卵体积、卵重之间的线性拟合显示,卵壳厚度、卵体积与气孔密度均无显著相关性（卵壳厚度：P = 0.11,卵体积：P = 0.09）,卵重、卵体积与卵壳厚度呈显著正相关（卵重：r2 = 0.46,P ＜ 0.001;卵体积：r2 = 0.44,P ＜ 0.001）;对7种鸟类卵的数据与繁殖期雌鸟平均体重的线性拟合结果显示：平均卵重、卵壳厚度的差异与雌鸟体重成正相关（卵重：r2 = 0.66,P = 0.03;卵壳厚度：r2 = 0.92,P ＜ 0.01）;对6种鸟类（缺乏粉红胸鹨窝卵数数据）卵的数据与孵卵相关变量的线性拟合结果显示：卵壳厚度及气孔率与窝卵数成负相关（卵壳厚度：r2 = 0.64,P = 0.056;气孔率：r2 = 0.87,P ＜ 0.01）,6种鸟类（缺乏树麻雀巢杯指数数据）气孔率与巢杯指数或巢型无显著相关性（巢杯指数：P = 0.49,巢型：P = 0.435）。卵表面积和总气孔数解释了大部分气孔率差异（87%）,卵重和气孔率与孵卵期无显著相关（P = 0.77）,气孔率显著低于预期气孔率（P＜0.001）。这些结果表明,种间的遗传性（如成鸟的形态、窝卵数等）决定了大部分卵与卵壳特性的差异,但是为适应高寒低氧的气候特征,不同种的鸟都具有相对厚的卵壳和低的气孔率特征,说明环境因素同样影响卵的进化。另外,单纯的卵特性（卵体积和气孔率）并不能决定孵卵期的长短,亲鸟的孵卵行为同样具有重要的影响,角百灵虽然离巢频率相对较高,但是孵卵期却相对较短,这可能与其较高的气孔率有关。     

高寒草甸三种雀形目雏鸟热调节机制的比较研究

３同巢型雏鸟大约在雏期的５０％开始出现调温机制。从变温到恒温的转变期呈现出两种发育趋势;黄嘴朱顶省发育迅速,角百灵和褐背拟地鸦发育缓慢。３种雏鸟产热量都随试验温度降低和日龄的增长而增加。但角百灵在３５℃时,产热量不随日龄增长而变化。     

高寒草甸几种雀形目鸟类的卵反射率分析

于2010~2013年的繁殖季节,在中国科学院海北高寒草甸生态系统定位站收集了9种青藏高原常见雀形目鸟类的卵,分别进行了反射率测量。测量光谱范围为可见光(400~750 nm)和短波近红外(750~1050 nm)。卵在两个波段光谱的反射率分别是0.066和0.123,二者差异极显著。在可见光范围内,除赭红尾鸲Phoenicurus ochruros的波峰在绿色光范围内,其他物种都在黄色光范围内;在短波近红外范围内,反射率明显分为3个组,以角百灵和小云雀的地面开放巢较高,黄嘴朱顶雀和黄腹柳莺的灌丛巢较低,其他种居中;开放巢及封闭巢的卵反射率在可见光范围无显著差异,但在短波近红外范围有显著差异。我们认为,在青藏高原高寒草甸生态系统中,植被郁闭度低,地面营巢环境不利于巢与卵的遮阳,造成营开放度高的地面巢的鸟卵近红外反射率相对较高,而灌丛巢和封闭巢的雀形目鸟类鸟卵相对较低,但对可见光谱的卵反射率各物种差异不显著。     

青海北部高寒草甸雀形目鸟类繁殖生态学的研究进展

从鸟巢特征、巢址选择、窝卵数、育幼行为、雏鸟生长发育、繁殖生产力以及繁殖对策等方面,对青藏高原高寒草甸雀形目鸟类繁殖生态学进行了综合分析与评述。高寒草甸雀形目鸟类受适合繁殖季节长度、食物资源和捕食压力的影响,或选择逐步投资对策,或选择一次投资对策;每个种群的常见窝卵数就是最适窝卵数;雏鸟的发育模式相对固定,不存在补偿性生长,但是生长期长度是可变化的。①研究亲-子通讯行为的进化和稳定性,提出适应高寒草甸雀形目鸟类的亲-子间的通讯行为假设;②建立在巢环境特征变化梯度(开放到封闭)上的生命表,找出决定适合度的生命表参数(繁殖率和存活率)的因果关系;③测定在巢环境特征变化梯度上的生态领域变化将是未来研究的3个方向。     

青藏高原常见雀形目鸟类的筑巢特征

于1990—2004年的繁殖季节,在青藏高原北部地区收集了12种常见的雀形目鸟类的巢,并且对这些鸟巢的分布格局和结构特征进行了比较研究。所有鸟巢分布表现出草地、灌木丛和沼泽的水平分割和地上、地面及地下的垂直分割的空间分布模式,其中地面杯状巢最普遍。巢结构特征,存在从简单到复杂的系列谱变化,主要表现:巢形状从浅到深,从开放到封闭;巢材性质从单一的植物性到复合的动植物性;巢材重从少到多。不管这些变化有多大,都反映了所有鸟种选择巢址是在安全和隔热两种基本条件之间权衡。在变化谱上的每种鸟巢都有自己的利弊,选择哪种类型的巢是由鸟本身的遗传和环境特征两方面的因素决定的。另外,巢材的运输反映了亲鸟对筑巢活动的投资,是繁殖投入的重要组成部分。因此,巢材重与亲鸟体重之比可以反映出筑巢活动投资的高低。百灵科鸟的开放式地面巢材重大约是亲鸟体重的1/2;而褐背拟地鸦的地下封闭巢的巢材重约为亲鸟体重的5倍以上。其余种类都在两者之间变化。总之,如此不同的投资差异是在捕食压力和种间竞争作用下以及亲鸟为满足鸟卵胚胎和雏鸟迅速生长发育的必要条件下,各种生物学特征协调的结果。     

山东聊城雀形目鸟类及其生态分析

报道了山东省聊城境内雀形目鸟类的分布,共记录到14科59种,其中留鸟13种;其它繁殖鸟15种;冬候鸟9种;旅鸟22种,近10年来调查资料显示,该区鸟类的物种数及多数种类的数量在不同季节和不同年份呈不稳定分布;约60%的鸟类的数量趋于减少;少数种类基本稳定（三道眉草Wu等）或呈增长趋势（灰喜鹊等）,[蒙古]百灵,文须雀为山东省分布新纪录。     

山东聊城雀形目鸟类及其生态分布

报道了山东省聊城境内雀形目鸟类的分布 ,共记录到 1 4科 5 9种。其中留鸟 1 3种 ;其它繁殖鸟 1 5种 ;冬候鸟 9种 ;旅鸟 2 2种。近 1 0年来调查资料显示 ,该区鸟类的物种数及多数种类的数量在不同季节和不同年份呈不稳定分布 :约 60 %的鸟类的数量趋于减少 ;少数种类基本稳定 (三道眉草等 )或呈增长趋势 (灰喜鹊等 )。 [蒙古 ]百灵、文须雀为山东省分布新纪录     

Morphological convergence in conifer-dwelling passerines

We tested for morphological convergence in conifer specialists among 88 passerines belonging to seven different phylogenetic lineages by discriminant factor analysis. We found a parallel trend among the seven lineages in body mass and digital pad morphology, whereas no such trends existed for the feeding and flight apparatus. Compared to the control species, the conifer specialists have smaller body masses and higher digital pads with maximal widths lying more distally within each of the seven lineages. These traits are interpreted as adaptations to dwelling among coniferous needles.Communicated by: F. Bairlein     

高寒草甸生态系统中牦牛体重和采食量动态模型的研究

高寒草甸生态系统中牦牛体重和采食量动态模型的研究黄大明（清华大学生物科学与技术系,北京１０００８４）赵松岭（兰州大学,兰州７３００００）Ｄｙｎａｍｉｃｍｏｄｅｌｓｏｆｙａｋｌｉｖｅｗｅｉｇｈｔａｎｄｉｔｓｉｎｔａｋｅｉｎａｌｐｉｎｅｍｅａｄｏｗｅｃｏ...     

高寒草甸生态系统牲畜种群结构和动态

本文用Leslie矩阵模型研究了高寒草甸生态系统牲畜种群结构及动态。模型考虑了更加精确的年龄组转移关系,出栏率是种群波动的主要因子。目前,牲畜种群结构不合理,种群数量不能保持平衡。     

高原鼠兔对高寒草甸土壤有机质及湿度的作用

为探讨高原鼠兔对土壤理化性质的作用, 本研究于2005年8月, 采用灼烧和烘干法, 分别测定了高原鼠兔栖息及被灭杀地区土壤有机质含量及湿度。结果表明： 高原鼠兔栖息地区, 0～5 cm及6～10 cm土壤层有机质含量和湿度均极显著或显著高于被灭杀地区; 11～30 cm 土壤层, 二者无显著的差异;31～50 cm土壤层, 有机质含量差异极显著, 而土壤湿度则无显著差异。说明, 高原鼠兔活动可增加高寒草甸土壤表层有机质含量和湿度, 进而改变土壤理化性质, 促进生态系统物质循环。     

高寒草甸生态系统牲畜种群的线性规划模型和最优化利用策略

本文研究了高寒草甸生态系统牲畜种群的线性规划模型和最优利用策略。以门源马场牧场的实际数据作为模型的一个例子,分别提出了藏羊、改良羊和牦牛的最优种群结构和最优出栏方案。在改良羊、藏羊、牦牛和马为主的牧场上,改良羊是牧场上的主要牲畜,牦牛和马保持其数量下限,藏羊全部淘汰。在藏羊、牦牛和马为主的牧场上,藏羊是牧场上的主要牲畜,牦牛和马保持其数量下限。按照线性规划模型方案经营,可提高经济收益,并减轻冬舂草场上牲畜的过多采食。价格分析说明青海省现行的畜产品价格体系需要调整。     

Plant community and soil available nutrients drive arbuscular mycorrhizal fungal community shifts during alpine meadow degradation

Arbuscular mycorrhizal fungi (AMF) play an important role in maintaining the function and sustainability of grassland ecosystem, but they are also susceptible to environmental changes. In recent decades, alpine meadows on the Tibetan Plateau have experienced severe degradation due to the impact of human activities and climate change. But it remains unclear how degradation affects the AMF community, a group of functionally important root associated microorganisms, which potentially limit the development and application of microbial technologies in the restoration of degraded grasslands. In this study, we investigated AMF communities richness and composition in non-degraded (ND), moderately degraded (MD) and severely degraded (SD) alpine meadows on the Tibetan Plateau, and then explored their main biotic and abiotic determinants. Alpine meadow degradation significantly reduced plant community biomass, richness, soil organic carbon, total nitrogen, total phosphorus, available nitrogen and available phosphorus, but increased soil pH. AMF community composition and the iesdominant family and genera differed significantly among different degradation stages. Grassland degradation shifted the AMF community composition in favor of Claroideoglomus over Rhizophagus, and resulted in a marked loss of Glomeraceae and the dominance of Diversisporaceae. Alpine meadow degradation significantly increased AMF hyphal density and richness, likely working as a plant strategy to relieve nutrient deficiencies or loss as a result of degradation. The structural equation model showed that AMF community richness and composition were significantly influenced by plant community, followed by soil available nutrients. Soil available nutrients was the key contributor to the increased AMF hyphal density and richness during grassland degradation. Our findings identify the effects of alpine meadow degradation on AMF richness and highlight the importance of the plant community in shaping the AMF community during alpine meadow degradation. These results suggest that plant community restoration should be the primary goal for the ecological restoration of degraded alpine meadows, and these soil functional microorganisms should be simultaneously integrated into ecological restoration strategies and management.     

Response of alpine meadow communities to burrow density changes of plateau pika (Ochotona curzoniae) in the Qinghai-Tibet Plateau

Plateau pika (Ochotona curzoniae) is a key component of alpine meadow ecosystem in the Qinghai- Tibetan Plateau, and the increase of its number leads plant components of alpine meadow ecosystem to adaptively response. A field survey was carried out to determine the response of alpine meadow community to population densities of plateau pika by using available burrow density to replace the population density of plateau pika. This study showed that the height of alpine meadow communities gradually increased, and the cover of alpine meadow communities firstly decreased, and then increased as the available burrow density increased. With the increase of available burrow density, the richness index of alpine meadow communities firstly decreased and then increased, and the evenness index of alpine meadow communities firstly increased and then decreased, however, the diversity index of alpine meadow communities firstly increased, and then decreased, finally increased. In the increasing process of available burrow density, the total plant biomass and the unpalatable plant biomass firstly decreased and then increased, and the palatable plant biomass firstly increased and then decreased, indicating that the palatable plant biomass was the highest and the unpalatable plant biomass was the lowest at 14 available burrow per 625 m². In the economic groups of plant biomass, the weed biomass was the highest and the legume biomass was the lowest at any available burrow densities, and the grass biomass and the sedge biomass were related to available burrow densities, indicating that the sedge biomass were bigger than the grass biomass at 3 available burrow per 625 m², inverse at 54 available burrow per 625 m², similar between 3 and 34 available burrow per 625 m². Accompanying by the increase of available burrow densities, the legume biomass and the sedge biomass significantly decreased (P < 0.05) and the legume became disappearance at 54 available burrow per 625 m²; the grass biomass firstly increased and then decreased, peaking at 14 available burrow per 625 m². The weed biomass firstly decreased and then increased, and was the lowest at 14 available burrow per 625 m². This study suggested that the responses of alpine meadow communities to population density of plateau pika at 14 available burrows per 625 m² were more sensitive than that at other available burrow per 625 m² from plant species diversity, biomass, height, cover and economic group.     

The effect of land management on plant community composition, species diversity, and productivity of alpine Kobersia steppe meadow

Grassland degradation is widespread and severe on the Tibet Plateau. To explore management approaches for sustainable development of degraded and restored ecosystems, we studied the effect of land degradation on species composition, species diversity, and vegetation productivity, and examined the relative influence of various rehabilitation practices (two seeding treatments and a non-seeded natural recovery treatment) on community structure and vegetation productivity in early secondary succession. The results showed: (1) All sedge and grass species of the natural steppe meadow had disappeared from the severely degraded land. The above-ground and root biomass of severely degraded land were only 38 and 14.7%, respectively, of those of the control. So, the original ecosystem has been dramatically altered by land degradation on alpine steppe meadow. (2) Seeding measures may promote above-ground biomass, particularly grass biomass, and ground cover. Except for the grasses seeded, however, other grass and sedge species did not occur after seeding treatments in the sixth year of seeding. Establishment of grasses during natural recovery treatment progressed slowly compared with during seeding treatments. Many annual forbs invaded and established during the 6 years of natural recovery. In addition, there was greater diversity after natural recovery treatment than after seeding treatments. (3) The above-ground biomass after seeding treatment and natural recovery treatment were 114 and 55%, respectively, of that of the control. No significant differences in root biomass occurred among the natural recovery and seeded treatments. Root biomass after rehabilitation treatment was 23–31% that of the control.