浅谈生态位理论在风景园林中的应用

生态位理论（niche）是生态学中的重要的理论之一，被广泛的应用在各个领域当中。而以生态学理论框架为依托，吸收现代地理学和系统科学之所长的景观生态学作为风景园林学科最重要的理论基础和实践准则，越来越多地受到关注。作者在简单介绍生态位理论的概念及发展历史的同时，尝试着从景观生态学的角度出发，研究生态位理论与风景园林学的关系及其在风景园林设计中的应用。     

攀枝花块菌资源及适宜生境初探

对攀枝花的块菌资源进行了较为系统的调查，查清了攀枝花的块菌种类、分布范围以及其生态环境．并与欧洲块菌主产国的气候环境进行比较，认为攀枝花是块菌生长的理想气候区之一，且得出块菌生长环境的pH值由弱碱性扩展到微酸性结论，同时采用Vanderloeg和Scavia选择系数Wi和选择指数Ei作为衡量块菌对生境适宜程度指标，提出了块菌适宜生境的标准。     

Microsoft Excel 2003在群落生态位参数计算中的应用

[目的]利用Microsoft Excel 2003的基本功能进行数据处理,快速高效地计算出常用的Levins生态位宽度值、Pianka生态位重叠值等参数。[方法]以南京紫金山的麻栎(Quercus acutissima)群落为例,运用Microsoft Excel 2003对该群落中主要优势乔木种类生态位数据进行分析。[结果]麻栎和黄连木的生态位宽度值分别为0.68和0.47。麻栎与其他8个物种的生态位重叠值分别为0.706、0.862、0.648、0.690、0.569、0.839、0.623和0.833,黄连木与其他7个物种的分别为0.485、0.772、0.416、0.498、0.490、0.612和0.324,枫香与其他6个物种的分别为0.588、0.523、0.821、0.653、0.548和0.615,马尾松与其他5个物种的分别为0.653、0.726、0.193、0.549和0.176。[结论]Microsoft Excel 2003具有适用范围广、实用等优点,值得在群落参数的计算和分析中进一步推广和应用     

Laboratory experiments on nematodes from natural CO2 springs reveal species-specific tolerance to extreme CO2 concentrations

This study focuses on the CO₂-tolerance of soil nematodes from natural CO₂ springs (mofette fields). In laboratory experiments, we compared survival, reproduction, activity and reactivation of a CO₂-sensitive species with a CO₂-tolerant species. Both species survived even 100% CO₂, but in an inactive state. The higher the CO₂ concentration the more individuals entered inactivity. We found significant differences between the two species: more adults of the CO₂-tolerant species maintained activity and reproduction at higher CO₂ concentrations. Moreover, reactivation after inactivity was faster. Together with a higher juvenile mortality of the CO₂-sensitive species, these interspecific differences are conclusive to explain the niche separation of the two species that was observed in the mofette field.     

日光温室枣树主要害虫及其天敌的生态位研究

对日光温室枣树主要害虫(枣瘿蚊、截形叶螨)与天敌在时间和空间序列上的生态位关系进行了研究,结果表明:枣瘿蚊所占的时间和空间生态位不大,截形叶螨表现出的时空生态位较宽。这两种主要害虫的时空生态位重叠值很小,说明这两种害虫对资源的利用差异很大。天敌对截形叶螨有较好的跟随作用,而对枣瘿蚊的控制作用较弱。     

苹果园蜘蛛群落组成及其生态位研究初报

对山西省晋中苹果园蜘蛛群落组成及其生态位研究结果表明,所采集的4447头蜘蛛隶属15科41属68种;并应用Berger-Parker优势度指数分析得出不同时期果园蜘蛛群落优势类群及优势种,根据二维生态位重叠值与物种间相似性指标进行模糊聚类分析,以λ=0.89为聚类阈值,可将8种果园优势种蜘蛛划分为2个明显竞争群及3个分离种。     

肇庆九龙湖水源涵养林黑桫椤群落主要种群生态位研究

以肇庆九龙湖水源涵养林黑桫椤群落的代表样地调查资料为基础,研究九龙湖水源涵养林黑桫椤群落20个物种的生态位特征。结果表明:黑桫椤群落主要物种的生态位宽度值大小依次为九节、假鹰爪、野山姜、鼎湖血桐、楼梯草、黑桫椤、金毛狗蕨、山篓、锡叶藤、铁线蕨、华南胡椒、新月蕨、水桐木、鸡血藤、柏拉木、大节茶、牛栓藤、广东润楠、粉单竹和山杜英;黑桫椤与牛栓藤、广东润楠之间有比较大的生态位重叠,其中黑桫椤与牛栓藤之间存在着激烈的竞争,而黑桫椤与广东润楠却是相互依存、共同繁荣;物种间的生态位重叠值与它们的生态位宽度大小并没有明显的正相关,生态位宽度小的物种之间也可能存在较大的生态位重叠。     

数据挖掘中关联规则的小生境遗传算法

根据关联规则挖掘的要求与特点,提出了一种新的基于小生境遗传算法的关联规则挖掘方法,该算法可以有效解决传统遗传算法搜索过早收敛的缺陷,实验结果显示,该方法能高效地解决关联规则挖掘问题。     

新疆伊犁荒漠草原恢复措施下植物群落生态位特征分析

以禁牧2 年、休牧(每年5 月底至10 月初)、补播杂花苜蓿2 年3 种恢复措施及处于自由放牧状态下的荒漠草原退化草地为研究对象, 分析了伊犁荒漠草原植物群落的生态位特征。结果表明: 在对照、禁牧、休牧样地中, 建群种伊犁绢蒿(Seriphidium transiliense)生态位宽度值最大, 分别为1.037、1.101 和1.070, 在补播样地中针茅(Stipa sp.)的生态位宽度值最大, 为0.798。较高的生态位重叠发生在生态位宽度较大的物种之间,但最大的生态位重叠发生在生态位宽度较小的物种之间。在4 种样地中, 伊犁绢蒿-角果藜(Ceratoides arenarius)之间存在较高的生态位重叠和较大的生态位相似比例, 证明2 个种群之间在资源利用上存在激烈的种间竞争。     

Predicting the invasion risk by the alien bee-hawking Yellow-legged hornet Vespa velutina nigrithorax across Europe and other continents with niche models

Vespa velutina nigrithorax, an Asian bee-hawking hornet, has been unintentionally introduced in south-western France before 2004 and is currently widely spreading across the country. Its arrival in northern Spain was reported in 2010. The potential invasion risk of the species is assessed using climatic suitability models. We used eight different modelling techniques within an ensemble forecast framework to show that the invasion success in south-western France could have been predicted using data from the native Asian range of the species, while we further used data from both the native and invaded ranges (including a recently established population in Korea) to better predict its potential invasion range across all continents. Results are discussed in terms of the interest of ecological niche modelling for invasion biology, realised niche of the invasive wasp, potential threats to native entomofauna and economic impacts of this new predator. A particular attention is paid to beekeeping activities that are nowadays already threatened by a wide panel of adversary factors.