Soil Organic Matter in Sustainable Agriculture

by Magdoff; Fred

• ISBN13: 9780849312946
• ISBN10: 0849312949
• Edition: 1st
• Format: Hardcover
• Copyright: 2004-05-27
• Publisher: CRC Press

Summary

Recognition of the importance of soil organic matter (SOM) in soil health and quality is a major part of fostering a holistic, preventive approach to agricultural management. Students in agronomy, horticulture, and soil science need a textbook that emphasizes strategies for using SOM management in the prevention of chemical, biological, and physical problems.Soil Organic Matter in Sustainable Agriculture gathers key scientific reviews concerning issues that are critical for successful SOM management. This textbook contains evaluations of the types of organic soil constituents-organisms, fresh residues, and well-decomposed substances. It explores the beneficial effects of organic matter on soil and the various practices that enhance SOM. Chapters include an examination of the results of crop management practices on soil organisms, organic matter gains and losses, the significance of various SOM fractions, and the contributions of fungi and earthworms to soil quality and crop growth.Emphasizing the prevention of imbalances that lead to soil and crop problems, the text also explores the development of soils suppressive to plant diseases and pests, and relates SOM management to the supply of nutrients to crops.This book provides the essential scientific background and poses the challenging questions that students need to better understand SOM and develop improved soil and crop management systems.

Table of Contents

Significance of Soil Organic Matter to Soil Quality and Health
Ray R. Weil
Fred Magdoff
Soil Quality, Soil Health, and Ecosystem Functions	1	(1)
Soil Quality Indicators, Perceptions, and Indices	2	(1)
Nature and Composition of SOM	3	(2)
Levels of SOC Accumulation in Relation to Global Greenhouse Effects	5	(1)
Influences on SOM Accumulation	6	(4)
Environmental Influences	6	(3)
Soil Management Practices That Influence the Balance between C Gains and Losses	9	(1)
SOM Influences on SQ Indicator Properties and Functions	10	(18)
Physical Properties Influenced by SOM	10	(1)
Soil Aggregation	11	(4)
Soil Water Availability	15	(3)
Chemical Soil Properties Influenced by Organic Matter	18	(1)
Nutrient Storage and Release	18	(2)
Microbial Enhancement of Nutrient Availability	20	(1)
Cation Exchange Capacity	20	(1)
Sorption of Organic Compounds	21	(1)
Anion Sorption	22	(1)
Metal Mobility	22	(1)
Soil pH Buffering and Amelioration	23	(1)
Growth-Regulating Substances	23	(1)
Biological Properties	24	(4)
Influence of Organic Residues and SOM Management on Crop Pests	28	(1)
Pools of Soil Organic Carbon	28	(5)
Relationship of SOM with Soil Productivity and Crop Yields	33	(1)
Conclusions	34	(2)
References	36	(10)
Soil Organic Matter Management Strategies
Fred Magdoff
Ray R. Weil
Patterns of SOM Changes	46	(2)
Practices for Improved SOM Management	48	(9)
Increasing C Inputs to Soil	48	(1)
Rotations and Crop Residue Management	49	(3)
Use of a Variety of Sources of Organic Materials	52	(2)
Decreasing SOM Losses from Soil	54	(3)
Effects of Management Practices on General SOM Levels	57	(1)
Use of Multiple Management Practices	58	(1)
Compensation for C Sequestration	59	(1)
SOM Management as a Foundation for Agricultural Pest Management	59	(3)
Conclusions	62	(1)
References	62	(6)
Soil Organic Matter Fractions and Their Relevance to Soil Function
Michelle Wander
History and Purpose of Organic Matter Measurement	68	(3)
Importance of SOM and Its Relationship to Management	68	(3)
Approaches to Organic Matter Fractionation	71	(1)
Types of Organic Matter in Mineral Soils and Their Probable Functions	72	(6)
Relationship between Dynamics and Measured Fractions	72	(1)
Commonly Described SOM Pools and Related Fractions	73	(1)
Fractions Equated with the Biologically Active Pool	73	(3)
Fractions Associated with Physically Active and Slow Pools	76	(1)
Fractions Associated with Recalcitrant Pools	77	(1)
Measures of POM and Their Interpretation	78	(12)
POM as an Index	78	(2)
Approaches to POM Fractionation and Interpretation of Results	80	(3)
Methods Yielding a Single POM Fraction	83	(4)
Methods Separating Fresh POM from Resident POM	87	(1)
Methods Separating Protected from Nonprotected POM	87	(3)
Summary	90	(1)
References	90	(13)
Stimulatory Effects of Humic Substances on Plant Growth
Yona Chen
Maria De Nobili
Tsila Aviad
Introduction	103	(4)
Indirect and Direct Effects --- An Essential Distinction	107	(1)
Indirect Effects	107	(1)
Direct Effects	107	(1)
Synergistic Effect of Nutritional Elements and HS on Plant Growth	108	(1)
Source and Nature of Soil and Water-Borne Organic Matter	109	(1)
Organic Matter Complexes with Metals: Nature, Properties, and Effects	109	(1)
Organically Bound Species of Micronutrient Cations	110	(1)
Transport of Micronutrients and Uptake by Plant Roots	111	(2)
Diffusion	112	(1)
Mass Flow (Convection, Miscible Displacement)	112	(1)
Stimulatory Effects of Soil-Derived HS on Plant Growth	113	(2)
Organo-Fe Complexes and Their Role in Plant Growth Enhancement	115	(4)
Iron Nutrition of Plants	115	(2)
Melon Plant Growth (Strategy I Plants): Experiment 1	117	(1)
Ryegrass Plant Growth (Strategy II Plants): Experiment 2	118	(1)
Compost-Derived HS and Plant Growth	119	(3)
DOM Extraction from Compost	121	(1)
Preparative Fractionation	121	(1)
Effects of DOM and Its Fractions on Plant Growth	121	(1)
Commercial HS and Their Effects on Plant Growth	122	(1)
Conclusions	123	(1)
Acknowledgments	124	(1)
References	124	(8)
Suppression of Soilborne Diseases in Field Agricultural Systems: Organic Matter Management, Cover Cropping, and Other Cultural Practices
Alexandra G. Stone
Steven J. Scheuerell
Heather M. Darby
Introduction	132	(1)
Disease Suppression in Field Soils	133	(20)
Types of Disease Suppression	133	(1)
Suppressive Soils	133	(1)
General and Specific Suppression	134	(1)
OM-Mediated General Suppression in Container Mixes	134	(1)
Diseases Caused by Pythium spp.	134	(1)
Diseases Caused by Phytophthora spp.	135	(1)
OM-Mediated General Suppression in Field Soils	136	(1)
Natural Soil Systems	136	(1)
Field Agricultural Systems	136	(1)
Orchard Systems	136	(1)
The Chinampa Agricultural System	137	(1)
Field Soils Amended with Paper Mill Residuals	137	(1)
Field Soils Amended with Dairy Manure Solids	137	(1)
OM-Mediated General Suppression and SOM Quality	137	(1)
Early Stages of Decomposition	138	(1)
Later Stages of Decomposition	139	(1)
Active OM and Suppression in a Compost-Amended Sand	139	(1)
Active OM, Microbial Activity, and Suppression in a DMS-Amended Silt Loan	140	(1)
Active OM and Suppression of Pythium DO in Historically Forested Soils	141	(1)
Organic Matter Quality: Amendment Rate and Serial Amendment	142	(1)
High-Rate Organic Amendment	142	(1)
Economics	142	(1)
Environmental Considerations	142	(1)
Agronomic Considerations	142	(1)
Efficacy	142	(1)
Low-Rate Organic Amendment	143	(1)
Organic Soil Management, or Long-Term Soil-Building	143	(1)
OM-Mediated Specific Suppression	143	(1)
Diseases Caused by Fusarium oxysporum	144	(1)
Diseases Caused by Rhizoctonia solani	144	(1)
Soilless Container Media	145	(1)
Field Soils	146	(1)
Mechanisms Involved in Disease Suppression	147	(1)
Microbiostasis	148	(1)
Microbial Colonization of Pathogen Propagules	149	(1)
Destruction of Pathogen Propagules	149	(1)
Antibiosis	150	(1)
Competition for Substrate Colonization	150	(1)
Competition for Root Infection Sites	150	(1)
Induced Systemic Resistance	151	(1)
Soil Chemical and Physical Properties	152	(1)
Soil and Plant Nutrient Status	152	(1)
Macronutrients	152	(1)
Micronutrients	152	(1)
Soil Physical Properties	153	(1)
Designing Suppressive Soils and Cropping Systems	153	(8)
Cultural Practices	154	(1)
Crop Rotation	154	(1)
Cover and Rotation Crops	154	(1)
Cover and Rotation Crops and General Suppression	155	(1)
Cover and Rotation Crops and Specific Suppression	155	(2)
Tillage	157	(2)
Inputs	159	(1)
Plant Genetics	159	(1)
Organic Amendments	159	(1)
Formulated Amendments	159	(1)
High N-Content Amendments	160	(1)
Inorganic Amendments	160	(1)
Microbial Inoculants	160	(1)
Examples of Disease-Suppressive Systems	161	(2)
Conclusion and Future Research Directions	163	(1)
OM-Mediated General Suppression	163	(1)
Beyond OM-Mediated General Suppression	163	(1)
References	164	(16)
Contributions of Fungi to Soil Organic Matter in Agroecosystems
Kristine A. Nichols
Sara F. Wright
Estimating Fungal Biomass	180	(1)
Saprophytic Fungi	180	(1)
Fungal Plant Pathogens	181	(1)
Biotrophic Mutualistic Fungi	182	(12)
Arbuscular Mycorrhizal Fungi	182	(2)
Glomalin, a Glycoprotein Produced by AM Fungi	184	(1)
Pools of Glomalin	184	(3)
Characterization of Glomalin	187	(1)
Glomalin, a Major Component of Soil Organic Matter	187	(1)
Quantities of Glomalin	187	(2)
Single-Species Pot Culture Experiments	189	(1)
Depth and Deposition Experiment	190	(1)
Glomalin and Aggregate Stability	191	(3)
Glomalin under Elevated CO2	194	(1)
Contribution of Soil Fungi to Organic Matter	194	(1)
Managing Soil Fungi to Increase Soil Organic Matter	195	(1)
References	196	(3)
Connecting Belowground and Aboveground Food Webs: The Role of Organic Matter in Biological Buffering
P. Larry Phelan
Introduction	199	(1)
Connecting Aboveground and Belowground Ecosystems	200	(11)
Upward Regulation: SOM and Soil Community Mediation of Plant Health	200	(2)
Possible Mechanisms of Mediation	202	(1)
Mineral Balance Hypothesis	203	(5)
Plant Signaling and Induced Resistance	208	(1)
Impacts on the Third Trophic Level	209	(1)
Downward Regulation: Aboveground Herbivory Modulates Soil Communities	210	(1)
Belowground Interactions	211	(8)
Soil Quality and Arthropods	211	(2)
Can Soil Invertebrates Act as Bioindicators of Biological Buffering?	213	(1)
Effects of Arthropods on SOM	214	(1)
A Diversity of Ecological Functions	214	(1)
Comminution and Digestion of Organic Litter	215	(1)
Regulation of Microbial Populations	216	(1)
Impact on Nutrient Cycling and Plant Productivity	217	(1)
Functional Redundancy and the Niche Concept	218	(1)
Conclusions and Future Directions	219	(1)
References	220	(7)
Tillage and Residue Management Effects on Soil Organic Matter
Alan J. Franzluebbers
Types of Tillage	227	(2)
Types of Residue Management	229	(1)
Effect of Tillage on Plant Growth	230	(7)
Effects of Disturbance/Tillage on Soil Organic Matter	237	(22)
Depth Distribution of Organic Matter	237	(5)
Aggregate-Size Distribution of Organic Matter	242	(3)
Total Organic C and N	245	(2)
Particulate Fraction of Organic Matter	247	(3)
Density Fractions of Organic Matter	250	(3)
Biologically Active Fractions of Organic Matter	253	(6)
Soil Organic Matter Affected by Interaction of Tillage with Cropping Intensity	259	(1)
Soil Organic Matter Affected by Interaction of Tillage with Soil Texture	260	(1)
Soil Organic Matter Affected by Interaction of Tillage with Climatic Region	261	(1)
References	261	(8)
Strategies for Managing Soil Organic Matter to Supply Plant Nutrients
Stefan Seiter
William R. Horwath
Introduction	269	(1)
Nutrients in Soil Organic Matter	270	(3)
Components of Soil Organic Matter Controlling Nutrient Storage	270	(1)
Processes Affecting Nutrient Availability in SOM	271	(2)
Crop Management Strategies	273	(6)
Cover Crops	273	(2)
Crop Rotations	275	(1)
Including Perennial Crops	275	(1)
Including High-Residue Crops	276	(1)
Including a Diversity of Crops	277	(2)
Tillage	279	(1)
Nutrient Applications	280	(5)
Inorganic Fertilizer	280	(1)
Animal Manure	281	(2)
Compost	283	(1)
Excess Nutrient Loading Associated with Organic Amendments	284	(1)
Conclusions	285	(2)
References	287	(8)
Soil and Crop Management Effects on Soil Microbiology
Ann C. Kennedy
Tami L. Stubbs
William F. Schillinger
Introduction	295	(1)
Soil Microbial Communities	296	(2)
Microbial Diversity	298	(2)
Nutritional Strategies	300	(1)
Management Effects on Soil Microbial Communities	301	(14)
Plant Influences	302	(1)
Roots and Rhizosphere	302	(1)
Plant Competition	303	(1)
Plant Diversity/Crop Rotation	303	(1)
Crop Residue	304	(2)
Resources	306	(1)
Nutrient Status/Cycling	306	(1)
Plant Growth-Regulating Compounds	306	(2)
Amendments	308	(1)
Agromicrobials	308	(1)
Arbuscular Mycorrhiza (AM)	308	(1)
Biological Control	309	(1)
Organic/Low-Input Farming	309	(1)
Genetically Modified Organisms (GMOs)	310	(1)
Disturbance	310	(1)
Tillage	311	(4)
Grazing	315	(1)
Strategies for Managing Microorganisms	315	(1)
Conclusions	316	(1)
References	316	(12)
Interactions among Organic Matter, Earthworms, and Microorganisms in Promoting Plant Growth
Clive A. Edwards
Norman Q. Arancon
Introduction	328	(1)
Breakdown of Organic Matter and Nutrient Cycling in the Field	329	(8)
Organic Matter Breakdown	329	(3)
Amounts of Organic Matter Consumed by Earthworms	332	(1)
Nutrient Cycling	333	(1)
Carbon	334	(1)
Nitrogen	335	(2)
Interactions between Earthworms and Microorganisms	337	(7)
Microorganisms in the Intestines of Earthworms	337	(2)
Populations of Microorganisms in Earthworm Casts and Burrows	339	(2)
Importance of Microorganisms as Food for Earthworms	341	(1)
Dispersal of Microorganisms by Earthworms	342	(1)
Stimulation of Microbial Decomposition by Earthworms	343	(1)
The Potential of Vermicomposting in Processing and Upgrading Organic Wastes as Plant Growth Media	344	(3)
Introduction	344	(1)
Scientific Basis for Vermicomposting Organic Matter	345	(1)
Vermicomposting Technologies Available	346	(1)
Effects of Vermicomposts on Plant Growth	347	(9)
Introduction	347	(1)
Effects of Vermicomposts on Growth of Greenhouse Crops	348	(3)
Effects of Vermicomposts on Growth of Field Crops	351	(2)
Physicochemical Changes in Soils in Response to Vermicompost Applications	353	(1)
Plant Growth Regulator Production in Vermicomposts	353	(3)
Effects of Vermicomposts on the Incidence of Plant Parasitic Nematodes, Diseases, and Arthropod Pests	356	(7)
Introduction	356	(1)
Vermicomposts in Suppression of Plant Parasitic Nematode Population	357	(1)
Suppression of Plant Diseases by Vermicomposts	357	(2)
Suppression of Insect and Mite Attacks by Vermicomposts	359	(4)
References	363