城市公园春季声景观与植被结构的关系

城市公园是城市生态系统的重要组成部分和城市生物多样性热点地区，具有丰富的声景观资源。由于声景观及声学方法具有信息量大，成本低，低侵入的特点，因此其研究和应用对生态系统健康及监测具有较高价值。声景观研究通过总结生物声的活动或多样性来衡量生物多样性。记录了北京20个城市公园的春季声景观，使用定量方法描述了声景观特征与变化；测试三种了已被证明与生物多样性相关并被广泛使用的声学指数（BIO、ADI、NDSI）与植被群落关系，完成了城市环境中声景观与环境关系的初步探究。研究结果表明：（1）声学指数能够有效表征城市公园声景观信息，具有显著的时间动态特性，能准确反映鸟类黎明合唱等重要生物生态活动；（2）声学强度指数也具有显著的时间动态变化和沿频率梯度的变化，不同的频率区间反映了不同声学群落的活动信息；（3）植被结构尤其是垂直结构对声景观起着重要作用，垂直异质性越大，声学多样性越高。发现支持声景观作为公园植被状况的度量，强调了其作为生物多样性和生态系统健康状况监测方法，用于城市管理和可持续发展的巨大潜力。     

Lysine Requirements of Rats of Various Body Weights

The lysine requirements of rats of various body weights were estimated using the feeding and isotope tests.

The regression equation obtained by the feeding test was Y= 1.03 – 0.58 log X. Where Y is lysine percentage of the diet and X is the mean of initial and final body weights (g) of rats achieving optimal growth gains during the feeding period.

The regression equation obtained by the isotope test was 7=0.90 – 0.49 log X, where Y and X are lysine percentage in the diet and body weights (g) of rats achieving optimal growth gains at the injection time respectively.     

An application case of ecological indicator values (Zeigerwerte) calculated with a simple algorithmic approach

Abstract

The vegetation of the study site near Rome (Castelporziano Estate), where different woodland types occur, was analysed on the basis of ecological indicator values (Zeigerwerte) for light, temperature, continentality of climate, soil moisture, soil pH and nitrogen. Indicator values were estimated with Hill's reprediction algorithm for the flora of Central-Southern Italy relying on a database of 4,207 original relevés representing a balanced survey of the vegetation of this and surrounding areas. It was possible to obtain indicator values for an important fraction of the Italian Mediterranean flora. Results are ecologically reasonable, and it was possible to find strong correlation between the recalculated values and a few environmental variables. These correlations were not significant in an analogous test with subjectively derived scores of Ellenberg indicator values.     

New syntaxa for the prodrome of Italian vegetation

The aim of this study is to provide new syntaxa for the Italian vegetation checklist. For the class Rhamno–Prunetea which includes the class Paliuretea the new alliance Rhamno saxatilis–Paliurion spinae-christi is described, that is included in the order Paliuretalia spinae-christi with a central-western Mediterranean and sub-Mediterranean distribution. Otherwise, the more thermophilous Paliurus spina-christi vegetation is included in the new suballiance named as Oleo sylvestris–Paliurenion spinae-christi within the alliance Oleo–Ceratonion of the class Quercetea ilicis. For the class Trifolio–Geranietea medii, a new alliance named Hyperico calabricae–Asphodelion macrocarpi is proposed here.     

Plant and lichen colonization in an asbestos mine: Spontaneous bioattenuation limits air dispersion of fibres

Abstract

Plant and lichen phytosociological studies describe the different dynamic stages of colonization. This approach has been applied to the Balangero asbestos mine, the most important of Western Europe up to 1990, which is a potential source for the air-dispersion of carcinogenic fibres. Vegetation relevés and maps have shown that plants and lichens develop spontaneously on the asbestos-rich substrates. Early colonization stages with low-covering hyperaccumulators, such as Thlaspi sylvium and Minuartia laricifolia, and with Thymus alpestris and T. cfr. humifusus, are followed, some decades later, by mature plant communities, which completely cover the asbestos-rich debris, thereby limiting the dispersion of fibres. Lichen colonization, even when limited to low covering early stages with pioneer crustose species, such as Scoliciosporum umbrinum and Candelariella vitellina, and young foliose thalli of Xanthoparmelia tinctina, is important whenever asbestos veins are exposed on serpentinite blocks and walls. Plants and lichens can be considered as bioattenuation (spontaneous bioremediation) agents in ecological recovery.