Classification of plant functional types based on the nutrition traits： a case study on alpine meadow community in the Zoigê Plateau

The ecological concept of Plant Functional Types（PFTs）, which refers to the assemblage of plants with certain functional traits, has been introduced for the study of plant responses to the environment change and human disturbance. Taking the alpine meadow community in the Zoigê Plateau as a study case, this paper classified PFTs in terms of plant nutrition traits. The sequential results are as follows.（1） The main herbages in the Zoigê Plateau included 16 species in 5 families. Among the five families, Cyperaceae vegetation accounted for 81.37%of herbage area in total, while the remaining 4families occupied less than 20%. As for the species,Kobresia setchwanensis Hand.-Maizz. was dominant,accounting for 48.74% of the total area; while the remaining 51.26% was comprised of Polygonum viviparum L., Anaphalis fiavescens Hand.-Mazz.,Stipa aliena Keng and other species.（2） By using the Principal Component Analysis（PCA）, the assessment of herbages nutrition was carried out based on the comprehensive multi-index evaluation model.Polygonum viviparum L. had the highest nutritional value score（1.43）, and Stipa aliena Keng had the lowest（-1.40）. Nutritional value of herbage species had a significantly positive correlation with altitude（P＆lt;0.01） in the Zoigê Plateau.（3） Based on the nutritional values, herbages in the Zoigê Plateau could be grouped into 3 nutrition PFTs（high, medium and low） by using the Natural Breaks（Jenks） method.

DIAGNOSIS AND SURGICAL MANAGEMENT FOR RETROSTERNAL THYROID MASS

<Abstract

Environment and management jointly shape the spatial patterns of plant species diversity of moist grasslands in the mountains of northeastern Yunnan

Grasslands account for about a quarter of the Earth's land area and are one of the major terrestrial ecosystems,with significant ecological and economic values.The influence of environmental factors and management types on grassland biodiversity has garnered considerable attention.This study investigated how patterns of species richness are influenced by geographical distance,environmental gradients,and management type in the moist mountain grasslands of northeastern Yunnan,China.We used structural equation modeling to disentangle the impacts of environment and management on phylogenetic community structure,and using partial Mantel tests estimated the roles of dispersal limitation and environmental filtering on taxonomic and phylogenetic beta diversity of three types of grasslands.Our results show that taxonomic alpha diversity increased in grazed grasslands and decreased in mowed grasslands,compared with protected grasslands.However,the phylogenetic structure of both grazed and mowed grassland communities was clustered,whereas that of protected communities was random.Moreover,both grazing and mowing significantly reduced the taxonomic and phylogenetic beta diversity of grasslands,with the lowest values observed in mowed grasslands.Both taxonomic and phylogenetic beta diversity were dominated by species turnover under different management types.The taxonomic and phylogenetic beta diversities of protected and grazed grasslands were simultaneously affected by environmental filtering and dispersal limitation,with the later playing a stronger role.In addition,mowing and following management measures had a stronger filtering effect on grassland community structure,as reflected by changes in community composition.

Advances in LID BMPs research and practice for urban runoff control in China

China is at present experiencing a very rapid urbanization process, which has brought a number of adverse impacts upon the water environment. In particular, urban runoff quantity and quality control have emerged as one of the key concerns for municipal officials. One of the strategies being considered is the use of a Low Impact Development type of Best Management Practices （LID BMPs） for urban storm water runoff quantity and quality control. In this paper, the situation surrounding urban runoff control in China is reviewed first. Then the conventional strategy and technologies for the construction and management of urban drainage systems are discussed, while exploring their inherent dilemmas. The LID BMPs are then introduced to control urban runoff in the context of urban sustainable water systems. After the comprehensive analysis of the various LID BMPs, the advances in LID BMPs research and practice for urban runoff control in China are investigated and summarized. At last, the difficulties of implementing LID BMPs in China are discussed, and a direction for the future is proposed.