農(nóng)田土壤有機(jī)碳和氮素固定是緩解氣候變化的重要措施,因此,影響土壤有機(jī)碳及氮素等養(yǎng)分平衡的土壤管理方式在全球范圍內(nèi)受到了極大關(guān)注。輪作及頻繁的耕作可改變秸稈的數(shù)量及質(zhì)量,進(jìn)而改變土壤養(yǎng)分動(dòng)態(tài)最終影響肥力狀況及土壤質(zhì)量。本研究通過(guò)長(zhǎng)期定位試驗(yàn),旨在分析評(píng)價(jià)不同耕作方式及秸稈還田處理對(duì)華北平原麥玉兩熟區(qū)土壤特性的影響,主要測(cè)定指標(biāo)包括：土壤養(yǎng)分(P、K、Mg、Ca、Mg、Na、Fe、Mn、Cu、Zn)、pH、容重和孔隙度的分布情況,以及土壤有機(jī)碳和氮的含量、儲(chǔ)量等。試驗(yàn)始于2001年冬小麥季播種前,共設(shè)4個(gè)處理：翻耕秸稈不還田(PTO)、翻耕秸稈還田(PT)、旋耕秸稈還田(RT)和免耕秸稈還田(NT)。 (1)與PTO、PT目比,NT和RT表層(0-10cm)土壤的有機(jī)碳、氮含量較高。各處理,土壤有機(jī)碳含量隨著土層的加深而下降。相對(duì)于PT, NT和RT土壤有機(jī)碳、氮含量隨土層加深而減少的趨勢(shì)更為顯著(P<0.05)。與PT相比,NT減少了對(duì)土壤的機(jī)械擾動(dòng),較RT和PT顯著提高了土壤容重(P<0.05)；從另一方面來(lái)講,NT處理下的土壤孔隙度最低,PT和PTO較NT顯著增加了土壤的...

【文章頁(yè)數(shù)】：111 頁(yè)

【學(xué)位級(jí)別】：博士

【文章目錄】：
摘要
ABSTRACT
CHAPTER 1 Introduction
    1.1 Introduction and background
    1.2 Motivation and problem statement
    1.3 Literature review
    1.4 Overview of soil tillage management and soil carbon
    1.5 Soil tillage effects on other soil properties related to SOC
    1.6 Main objectives
CHAPTER 2 Materials and methods
    2.1 Site description
    2.2 Experimental design
    2.3 Soil sampling
    2.4 Soil analysis
    2.5 Statistical analysis
CHAPTER 3 Effects of tillage systems and residue management on selected soil physical andchemical properties
    3.1 Introduction
    3.2 Effects of different tillage systems ad residue management on soil chemical properties
    3.3 Effects of different tillage systems ad residue management on soil physical properties
    3.4 Discussion
    3.5 Summary
CHAPTER 4 Effects of tillage and residue management on selected soil carbon fractions
    4.1 Introduction
    4.2 Effect of different tillage systems ad residue management on soil carbon fractions
    4.3 Discussion
    4.4 Summary
CHAPTER 5 Effects of tillage and residue management on soil organic carbon concentration, stocksand stratification
    5.1 Introduction
    5.2 The effects of different tillage systems and residue management on soil carbon dynamics
    5.3 Discussion
    5.4 Summary
CHAPTER 6 Effects of tillage and residue management on nitrogen concentration, stocks andstratification
    6.1 Introduction
    6.2 The effects of different tillage systems and residue management on nitrogen dynamics
    6.3 Discussion
    6.4 Summary
CHAPTER 7 Relationship of soil organic carbon and other soil quality parameters as affected bytillage and residue management
    7.1 Introduction
    7.2 Results
    7.3 Discussion
CHAPTER 8 Summary, recommendations and conclusions
References
Acknowledgement
Abridged resume



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