有机废物对土壤-水稻系统中重金属行为及水稻生长和产量的影响研究

摘要

Heavy metals in the soil pose a great threat to the environment and ultimately to thehumans through bioaccumulation．A variety of heavy metals are reported to enter thefood chain through uptake by the major crops therefore instigating a vicious cycle ofbeing transferred and retransferred across various trophic levels．This continuum is athreat to the quality and quantity of principal staple foods for instance paddy rice．In thisregard the most notorious element is Copper (Cu) for its efficient mode of uptake bygains and its lethal impact on grain production．Many organic and inorganic substratesassociated with crops include potential sources of heavy metals．One such example is thatof organic fertilizers whose main purpose is to increase the fertility of soil by providingessential nutrients, and to increase crop production by limiting the heavy metals bioavailability．Another utility is the provision of contaminant free food．Contemporaryliterature recognizes these organic fertilizers including manures as source ofcontaminants like Cu．The present research was conducted to evaluate the effect of heavymetal Cu on the growth and production of paddy rice．Different levels of Cu pollutionwere explored．The response of manure to Cu pollution in soil and on to rice growth,production and quality was assessed.

目录

英文文摘

论文说明：List of Tables、List of Figures

声明

ACKNOWLEDGEMENTS

1 General Introduction

1.1 Research Problem

1.2 Research Objectives

1.3 Hypothesis

2 Review of Literature

2.1 Impact and Fate of Copper in the Environment

2.2 Environmental Fate and Behavior in Soil

2.2.1 Adsorption and mobility

2.2.2 Aqueous-phase solubility

2.2.3 Leaching and lateral movement

2.2.4 Biotransformation

2.3 Effect of Cu on Paddy Rice Growth and Production

2.4 Choices of Manure in terms of Fertilizers and Amendments

2.5 Heavy metals pollution caused by massive use of manure

3 Impact of Different Concentration of Cu on Growth and Yield of Rice

3.1 Introduction

3.2 Material and Methods

3.2.1 Soil and manure properties

3.2.2 Preparation of the pots

3.2.3 Methods for determining growth parameters

3.2.4 Determination of plant biomass

3.3 Experimental Design

3.4 Results

3.4.1 Effect of different Cu treatments on plant height

3.4.2 Effect of different Cu treatments on chlorophyll contents

3.4.3 Effect of different Cu treatments on tillering

3.4.4 Effect of Cu on plant biomass (tillers, shoots and roots)

3.4.5 Effect of Cu on grain yield and yield components

3.4.6 Correlation analysis of grain yield and yield components

3.5 Discussion

4 Accumulation of Cu in Rice at Different Concentration Levels of Cu

4.1 Introduction

4.2 Material and Methods

4.2.1 Determination of Cu contents in rice plants

4.3 Statistical Analysis

4.4 Results

4.4.1 Cu accumulation in roots

4.4.2 Cu accumulation in shoots

4.4.3 Cu accumulation in grains

4.4.4 Relationship of Cu content among roots, shoots and grains

4.5 Discussion

5 Dynamics and Accumulation of Cu in the Soil and Its Affect on Plant Absorption

5.1 Introduction

5.2 Material and methods

5.2.1 Determination of extractable Cu contents in soil

5.2.2 Determination of total Cu contents in soil

5.3 Results

5.3.1 Dynamics of extractable Cu in the soil

5.3.2Total Cu contents of the soil at the harvesting

5.3.3 Correlation between soil extractable Cu and the content in plant

5.3 Discussion

6 Major Conclusions and Perspectives

6.1 Major conclusions

6.2 Future perspectives

References