理解自然界中生物群落的形成與構(gòu)建機(jī)制是生態(tài)學(xué)研究的核心問(wèn)題之一。當(dāng)前,研究者對(duì)于人類活動(dòng)干擾如何影響生物群落構(gòu)建以及其內(nèi)在各功能組分的化學(xué)計(jì)量學(xué)特征仍所知甚少。在全球范圍內(nèi),家畜的放牧活動(dòng)與割草是草地生態(tài)系統(tǒng)主要的兩種人為管理方式。這些人類活動(dòng)可以對(duì)草地系統(tǒng)的土壤理化性質(zhì)、植被與昆蟲(chóng)的群落結(jié)構(gòu)與組成,以及三者的碳（C）,氮（N）和磷（P）含量及其化學(xué)計(jì)量學(xué)特征產(chǎn)生深遠(yuǎn)影響。在過(guò)去幾十年,大量的研究對(duì)放牧與割草對(duì)草地生態(tài)系統(tǒng)土壤、植物和昆蟲(chóng)群落進(jìn)行了單獨(dú)的研究。然而,很少研究同時(shí)比較兩種管理方式對(duì)土壤、植物和昆蟲(chóng)等不同生物與非生物組成特征的影響,尤其是在同一個(gè)草地生態(tài)系統(tǒng)中。這些研究不足,一方面極大地限制了對(duì)自然草地生物群落構(gòu)建方式與機(jī)制的理解,另一方面不利于相關(guān)決策部門制定合理科學(xué)的草地管理措施。在我國(guó)東北的松嫩草地,本研究通過(guò)一個(gè)為期4年的野外原位控制實(shí)驗(yàn),開(kāi)展中等強(qiáng)度的家畜放牧（牛）與人工割草如何影響草地生態(tài)系統(tǒng)土壤、植物和昆蟲(chóng)群落特征的比較研究。一方面比較了放牧與割草對(duì)草地土壤理化性質(zhì),植物與昆蟲(chóng)群落結(jié)構(gòu)與組成等特征的影響;另一方面,比較了放牧與割草如何影響土壤、優(yōu)勢(shì)種植物（羊草... 

【文章頁(yè)數(shù)】：111 頁(yè)

【學(xué)位級(jí)別】：博士

【文章目錄】：
abstract
中文摘要
Chapter1:Introduction
    1.1 Background and research progresses
        1.1.1 General features of grasslands
        1.1.2 Utilization of grazing and mowing
        1.1.3 Livestock grazing and soil properties in grasslands
        1.1.4 Livestock grazing and plant community in grasslands
        1.1.5 Livestock grazing and insect community in grasslands
        1.1.6 Mowing and soil properties in grasslands
        1.1.7 Mowing and plant community in grasslands
        1.1.8 Mowing and insect community in grasslands
        1.1.9 Trophic cascades in grasslands
    1.2 Ecological stoichiometry
    1.3 Ecological stoichiometric linkages among trophic levels
    1.4 Justification
    1.5 Aims and scope of the study
Chapter2:Materials and methods
    2.1 Study area
        2.1.1 Geographical overview
        2.1.2 Experimental site
    2.2 Experimental design and treatment
    2.3 Soil sampling and measurement
    2.4 Plant and litter sampling
    2.5 Insect sampling and measurement
    2.6 Chemical analyses for insect total C,N and P
    2.7 Insect feeding behavior
    2.8 Statistical analyses
Chapter3:Effects of grazing and mowing on soil Physiochemical properties
    3.1 Introduction
    3.2 Materials and methods
    3.3 Results
        3.3.1 Grazing/mowing and soil physical properties
        3.3.2 Grazing/mowing and soil chemical properties
        3.3.3 Relationships among soil nutrients and their ratios
    3.4 Discussion
        3.4.1 Effects of grazing and mowing on soil physical properties
        3.4.2 Effects of grazing and mowing on soil stoichiometry
        3.4.3 Effects of grazing ang mowing on soil C:N:P ratios and their relationship
    3.5 Conclusions
Chapter4:Effects of grazing and mowing on plant community diversity and productivity
    4.1 Introduction
    4.2 Materials and methods
    4.3 Results
        4.3.1 Grazing/mowing and plant community diversity
        4.3.2 Grazing/mowing and shoot,root and total biomass
        4.3.3 Grazing/mowing and ratios among shoot,root and total biomass
        4.3.4 Grazing/mowing and grasses and forbs biomass
        4.3.5 Grazing/mowing and ratios among grass,forb and shoot biomass
        4.3.6 Grazing/mowing and litter biomass
        4.3.7 Relationships between plant species evenness and shoot,root,and shoot biomass
        4.3.8 Relationships between plant species richness and shoot,root,and shoot biomass
        4.3.9 Grazing/mowing and grass,forb,and total density
        4.3.10 Grazing/mowing and ratios among grass,forb and total density
        4.3.11 Grazing/mowing and mean,grass and forb height
    4.4 Discussion
        4.4.1 Effects of grazing and mowing on plant community diversity
        4.4.2 Effects of grazing and mowing on plant community productivity
        4.4.3 Relationship between biomass and diversity
        4.4.4 Effect of grazing and mowing on plant community composition
    4.5 Conclusions
Chapter5:Effects of grazing and mowing on insect diversity and abundance
    5.1 Introduction
    5.2 Materials and methods
    5.3 Results
        5.3.1 Grazing/mowing and total insect diversity
        5.3.2 Grazing/mowing and total insect abundance
        5.3.3 Grazing/mowing and insect abundance of different trophic groups
        5.3.4 Relationships between plant species evenness and insect diversity
        5.3.5 Relationships between plant species richness and insect diversity
        5.3.6 Relationships between plant biomass and total insect abundance
        5.3.7 Relationship between plant biomass and herbivore insect abundance
    5.4 Discussion
        5.4.1 Effects of grazing and mowing on insect diversity
        5.4.2 Effects of grazing and mowing on insect community composition
        5.4.3 Relationship among plant,insect diversity and abundance
    5.5 Conclusions
Chapter6:Effect of grazing and mowing on ecological stoichiometric linkages amongtrophic levels
    6.1 Introduction
    6.2 Materials and methods
    6.3 Results
        6.3.1 Grazing/mowing and soil nutrients concentration and C:N:P stoichiometry
        6.3.2 Grazing/mowing and plant nutrients concentration and C:N:P stoichiometry
        6.3.3 Grazing/mowing and insect nutrients concentration and C:N:P stoichiometry
        6.3.4 Grazing/mowing and insect feeding behavior
    6.4 Discussion
        6.4.1 Effects of grazing and mowing on soil and plant stoichiometry
        6.4.2 Stoichiometric characteristic response to insect abundance and feeding behavior
    6.5 Conclusions
Chapter:7 General conclusions
    7.1 Main conclusions
    7.2 Suggestions for further research and management implications
References
Acknowledgements
List of publications



本文編號(hào)：3713306