贵阳喀斯特山地云贵鹅耳枥种群结构和动态初探

本文对贵阳喀斯特山地云贵鹅耳枥种群结构和动态进行了探讨。结果表明：(1)云贵鹅耳枥种群大小结构分初始增长型、增长型、稳定型、始衰型、中衰型、老衰型和偏途顶极型等7种类型,并呈现由初始增长型过渡到老衰型的变化;(2)云贵鹅耳枥种群分布格局呈集群型和随机型,分布格局的变化有一定的规律性,即种群在其散布和发展阶段多趋于集群型,而在其衰退阶段趋于随机型;(3)云贵鹅耳枥种群密度随时间变化呈现负增长;(4)云贵鹅耳枥种群是先锋种群,但在裸岩陡坡等特殊生境中亦能形成稳定的群落。     

Winter habitat selection by wild boar <Emphasis Type="Italic">Sus scrofa</Emphasis> in southeastern Poland

Research was conducted on habitat selection by the wild-boar population in the Carpathian foothills, southeastern Poland. In two forest districts (Bircza and Krasiczyn) with a total area of forests of 47,000 ha, 21 line transects were designated (total length, 284 km). In February 2001, tracks that wild boar left during the day were counted on five subsequent days. Using a car mileage meter and forest maps, the locations of tracks in seven forest types, forest meadows and agricultural fields situated inside the forests were determined. The Bailey’s test was applied to calculate the boars’ preference for each forest type and non-forest areas. Spatial distribution of 284 wild-boar tracks shows that the animals do indeed prefer European beech–hornbeam Fagus silvatica–Carpinus betulus forest and avoid silver fir Abies alba forest. The hypothesis raised is that in the European beech–hornbeam forests, there are foraging areas and bedding sites crucial for the animals.     

云贵鹅耳枥群落演替中乔木树种间协变的研究

采用Ｓｐｅａｒｍａｎ秩相关系数探讨了贵阳喀斯特山地云贵鹅耳枥群落演替中１６种常见乔木树种间的协变,并对这些乔木树种间的协变关系及其对群落的性质、结构和动态的影响进行了分析。     

Forest characteristics and population structure of a threatened palm tree Caryota obtusa in the karst forest ecosystem of Yunnan,China

中国云南石灰岩山地森林系统中受到威胁的董棕的森林特征和种群结构 别具魅力的董棕(Caryota obtusa)属于棕榈科(Arecaceae)的树种,在中国西南地区、印度、缅甸、泰国、老挝和越南有自然分布。董棕是一个具有重要经济价值且受到人为活动威胁的物种,其在云南的一些石灰岩山地乔木层占据优势。本研究的目的是阐明在云南石灰岩山地森林生态系统中董棕的群落结构、物种多样性、种群现状及其更新动态。为了全面深入的调查董棕群落,我们在云南南部10个县设置56个样方。根据样方数据,我们分析了群落的垂直结构、物种组成和种群结构,并对当地村民进行问卷采访记录了长期以来人为活动对董棕林的干扰情况。研究结果表明,董棕棕榈林分布在石灰岩山坡和沟谷,有7个群落类型。每个群落的垂直结构明显,分为乔木层、灌木层和林床。群落物种组成丰富,各群落类型的木本物种和草本物种的香农-维纳多样性指数均在2.1–3.8。董棕在胸径级上的分布为多峰型,属间歇性更新,且依赖于一定的自然干扰,董棕小树主要在无人为干扰或人为干扰小的群落中出现,重度人为干扰严重地阻碍了董棕的更新,其次的中度人为干扰也给董棕的更新带来了一定的困难。     

黔中山地喀斯特森林的水文学过程和养分动态

采用不同林分类型固定样地的定位研究方法,研究了黔中山地喀斯特森林对降水量的分配和随降水流动的主要离子的影响。结果表明,林内外年降水量的变化趋势为:空旷地>林隙>乔木层>灌草层>地表和壤中流量>树干径流量。年降水在林内不同层次分配量的变化趋势为:林地蒸发等量>灌草层降水截留总量>林冠层降水截留总量。相关水量的月动态趋势以夏季较高,冬季较低。森林最大持水量的变化趋势为土壤层>植被层。植被层最大持水量的变化趋势为乔木层>枯落物层>灌木层>草本层。喀斯特原生林植被层地上部分最大持水量为28.20 mm,是喀斯特次生林的194.48%。喀斯特原生林土壤层最大持水量加权值为19.24 mm,是喀斯特次生林的187.89%。喀斯特原生林冠层降水截留总量、灌草层降水截留总量、地表蒸发等量总值占空旷地降水量的比例为97.93%,喀斯特次生林的相应值为97.89%。喀斯特原生林的调水能力大于喀斯特次生林。土壤层最大持水量占植被-土壤系统的95.88%~96.11%,保土可增加蓄水。合理调整森林植被层结构既可防治土壤侵蚀,又可提高森林的最大持水潜力。随降水流动的 \mathrm{S} {\mathrm{O}}_4^{2-} 、Ca²⁺、Mg²⁺、 \mathrm{N} {\mathrm{H}}_4^{+} 、K⁺、 \mathrm{N} {\mathrm{O}}_3^{-} 、Cl^-、Na⁺ 月均浓度在不同喀斯特森林类型的林隙、林内和树干径流中的年变化规律明显,夏季浓度较低,冬季浓度较高。固定样地集水区溪流中相关离子月均浓度变化趋势与林隙、林内和树干径流中的不同。喀斯特原生林年随降水输入的相关离子量为430.951 kg·hm^-2·a^-1,随地表径流和90 cm壤中流的输出量为49.789 kg·hm^-2·a^-1,年随降水净增的相关离子量为381.162 kg·hm^-2·a^-1;而喀斯特次生林的相应值为304.101、39.216和264.885 kg·hm^-2·a^-1。喀斯特原生林N^3-、K⁺、Ca²⁺、Mg²⁺储量高于喀斯特次生林,土壤层储量>植被层储量,植被层储量中乔木层>枯落物层>灌木层>草本层。年随降水输入喀斯特森林的相关离子量占植被-土壤系统的总量较小、有效性较高,对森林的生长和养分循环有重要的生态学意义。     

Use of limestone karst forests by Bornean orangutans (Pongo pygmaeus morio) in the Sangkulirang peninsula, east Kalimantan, Indonesia

The Indonesian province of East Kalimantan is home to some of the largest remaining contiguous tracts of lowland Dipterocarp forest on the island of Borneo. Nest surveys recently conducted in these forests indicated the presence of a substantial population of Eastern Bornean orangutans (Pongo pygmaeus morio) in the Berau and East Kutai regencies in the northern half of the province. The Sangkulirang Peninsula contains extensive limestone karst forests in close proximity to the lowland Dipterocarp forests inhabited by orangutans in these regencies. Orangutans have been sighted in these limestone karst forests, but the importance of this forest type for orangutans has been unclear. Therefore, we conducted 49 km of nest surveys in limestone karst forest to obtain the first quantitative estimates of orangutan densities in this habitat, and walked 28 km of surveys in nearby lowland Dipterocarp forests for comparison. We also gathered basic ecological data along our transects in an attempt to identify correlates of orangutan abundance across these habitat types. Undisturbed limestone karst forests showed the lowest orangutan densities (147 nests/km(2), 0.82 indiv/km(2)), disturbed limestone forests had intermediate densities (301 nests/km(2), 1.40 indiv/km(2)), and undisturbed lowland Dipterocarp forests contained the highest density (987 nests/km(2), 5.25 indiv/km(2)), significantly more than the undisturbed limestone karst forests. This difference was not correlated with variation in liana abundance, fig stem density, or stump density (an index of forest disturbance). Therefore, other factors, such as the relatively low tree species diversity of limestone karst forests, may explain why orangutans appear to avoid these areas. We conclude that limestone karst forests are of low relevance for safeguarding the future of orangutans in East Kalimantan.     

Earthworm (Oligochaeta,Lumbricidae) Populations of the Karasu River Basin (Central Caucasus)

The species composition, population structure, and synecological characteristics of earthworms inhabiting forest and meadow formations of unique beech–hornbeam woodland of the Karasu River basin have been studied. Thirteen Lumbricidae species were found. The species composition and earthworm population structure depend on phytocenosis edificators. The greatest diversity, namely, species, chorological, and ecological, was recorded in soils of relict beech phytocenosis. It was shown that in the case of forest clearing its earthworm’s fauna remains intact. In the secondary meadows, the following was noted: the lowest species diversity of Lumbricidae, domination of soil species proper, and dramatically increasing diversity indices compared to forest associations.     

喀斯特峰丛洼地不同生态系统的土壤肥力变化特征

基于喀斯特峰丛洼地坡耕地、草丛、灌丛、人工林、次生林、原生林6种典型生态系统的土壤主要养分、矿质养分和微生物这3组变量共计20个指标的调查、取样和分析,运用多重比较分析、主成分分析和典范相关分析探讨了其土壤肥力变化特征、主要影响因子及两两之间的相互关系。结果表明,喀斯特峰丛洼地土壤pH值为6.60—7.75,土壤主要养分、微生物种群数量和微生物生物量明显高于同纬度地区地带性红壤,矿质养分含量相对较低,其中SiO2、Al2O3、Fe2O3占矿质全量的90%以上。土壤肥力的总体趋势为原生林>次生林>灌丛>草丛>坡耕地>人工林。喀斯特石漠化地区实行林草结合的退耕还林还草模式更有利于土壤生态系统的环境改善,坡耕地应多施有机肥和氮肥,人工林应多施氮肥。原生林植物与养分之间达到了良好的平衡状态,主要应加强森林抚育管理,改善森林环境,保障植物、土壤养分及微生物之间的良好协调关系。确保土壤资源的合理利用,促进喀斯特峰丛洼地乃至整个西南喀斯特区域植被的迅速恢复和生态重建。     

喀斯特季节性雨林蚬木种群的增长模型

蚬木是喀斯特季节性雨林的优势种和特征种,研究蚬木种群的增长过程将为深入理解喀斯特季节性雨林动态提供基础。根据一个15hm2固定样地的调查数据,采用logistic模型及其4种改进模型对蚬木种群的增长过程进行了拟合,用残差平方和、决定系数和AIC准则对拟合的模型进行评价。结果表明:李新运模型和刘金福模型的拟合效果较好,但综合考虑模型的拟合效果和模型的简洁性,logistic模型和S形增长过程模型为较优模型。用logistic模型对蚬木种群的增长过程进行深入分析发现,种群增长最快的时期为50a左右,而在150a后,种群逐渐进入增长饱和期。种群目前接近增长饱和期,所以应加强保护,以维持蚬木群落的稳定发展。