The Response Of Common Species To Fertilization Based On Plant Traits In Tibetan Plateau Alpine Meadow

Plant functional groups (PFGs) is assemblage of plants which have certain functional characteristics, and is an ecological concept introduced by ecologist in order to study the response of vegetation to climate changes and disturbances. At present the key problem about PFGs still is the plant feature selection applying to classication of PFGs. According to the partition methods of plant functional groups which are done by characteristics of Plant Biology, there exists limitations to answer the key ecological issues in the context of global environmental change, for example, the response of ecosystem toward disturbances, the mechanism of ecosystem function transformation and so on. Now mounting ecologists assume that species division in the particular ecosystem according to the response of plant traits to disturbances is a very promising approach to answer the above questions. But so far there have been less reports of research about alpine meadows plants of Qinghai Tibetan plateau used the method of classification. Meanwhile at present it's not clear about the mechanism of influencing species relative abundances, and the relationship between species relative abundances and plant traits. Therefore, the aim of this experiment is trying to explore quantity characteristics and change range of different plant traits, divisions of plant functional group which are based on the response of plant traits to different fertilizer treatments, and the relationship between species relative abundances and plant traits at species level, which are through investigating the responses of the six functional traits and species relative abundances of 12 dominating species of alpine meadows community in the east of Qinghai-Tibetan plateau toward different fertilizer treatments.The main research results are as follows:1. The response of alpine meadows plant traits is comparatively complex under different fertilizer treatments and do not divide into Legumes, Gramineae and non-Legume and non-Gramineae forbs according to classical plant taxonomy naturalized;2. When fertilization is 15g/m2,12 dominating species could be divided into three plant groups according to the responses of six plant traits, which are as follow:â‘ (Thermopsis lanceolata)+(Anemone rivularis)+(Elymus nutans)+(Kobresia capillifolia) +(Euphorbia allolibelicu)+(Astragalus polycladus)+(Pleurospernum szechenyii):â‘¡(Pou crymophila)+(Oxytropis ochrocephala)+(Koeleria cristata);â‘¢(Agroslis hugoniana)+ (Anemone obtusiloba).3. When fertilization is 30g/m2,12 dominating species could be divided into four plant groups according to the responses of six plant traits, which are as follow:â‘ (Kobresia capillifolia)+(Astragalus polycladus)+(Thermopsis lanceolata)+(Anemone rivularis)+(Anemone obtusiloba);â‘¡(Poa crymophild)+(Elymus nutans)+(Agrostis hugoniana);â‘¢(Koeleria cristata)+(Oxytropis ochrocephala);â‘£(Euphorbia altotibetica)+ (Pleurospermum szechenyii).4. When fertilization is 60g/m2,12 dominating species could be divided into four plant groups according to the responses of six plant traits, which are as follow:â‘ (Thermopsis lanceolata)+(Anemone rivularis)+(Anemone obtusiloba)+(Kobresia capillifolia)+(Astragalus polycladus)+(Pleurospermum szechenyii);â‘¡(Poa crymophila)+ (Agrostis hugoniana)+(Koeleria cristata)+(Elymus nutans);â‘¢(Oxytropis ochrocephala);â‘£(Euphorbia altotibetica).5. In terms of the six plant traits analyzed in this research, species relative abundances are significantly correlated with specific leaf area (SLA) and leaf dry matter content (LDMC) under the fertilization treatments, which's correlations chang along with the change of fertilization. This result confirms that exclusively stochastic processes don't affect species relative abundances, which is correlated with plant traits. And their correlations change as the environment changes.