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Soil fertility management for sustainable agriculture. | 1997

Soil fertility management for sustainable agriculture

J. F. Power; Rajendra Prasad

Introduction Sustainable Agriculture: Definitions and Goals Factors Determining Sustainability Soil Fertility Essential Plant Nutrients Criteria for Essentiality Basis for Classification of Nutrients as Primary, Secondary, and Micronutrients Primary Nutrients, Secondary Nutrients, and Micronutrients Functions of Essential Nutrients in Plants Soil the Sustainer Soil Organic Matter Soil Water Soil Air Soil Mineral Matter Soil Colloids Soil Living Organisms Soil Colloids Clay Minerals Oxide Minerals Organic Matter Humus, Its Structure and Properties C:N Ratio Factors Affecting the Organic-Matter Content of Soils Soil Acidity Acids The pH Concept Determination of Soil pH Active and Potential Acidity Buffering Capacity Nature of Soil Acidity Factors Affecting Soil Acidity Soil pH and Crop Production Lime Requirement Liming Materials Fineness of Limestone Soil Salinity and Sodicity Coverage and Special Features Criteria for Determining Salinity/Sodicity Classification Reclamation and Management of Saline Soils Crop Production on Saline Soils Reclamation and Management of Sodic Soils Crop Production on Sodic Soils Nitrogen Soil Organic N Mineralization of Soil Organic Nitrogen Factors Affecting Nitrification Nitrogen Immobilization Ammonium Fixation (Nonexchangable Ammonium) NH4 vs. NO3- Nutrition of Plants Biological Nitrogen Fixation Nitrogen Fertilizers or Industrial Nitrogen Fixation Efficient Nitrogen Management Increasing N Use Efficiency Nitrogen Availability Indices Nitrogen-Deficiency Symptoms Phosphorus Soil Phosphorus Phosphate Retention or Fixation in Soil Factors Affecting the Retention of Phosphorus by Soil Phosphate Fertilizer Reaction Products in Soil Intensity (I) and Quantity (Q) Factors in Phosphorus Availability Soil Testing for Phosphorus Phosphorus-Deficiency Symptoms in Plants Phosphate Fertilizers Efficient Phosphate Management Potassium Forms of Soil Potassium Quantity/Intensity Relationships Potassium Fixation Leaching of Potassium Potassium Fertilizers Efficient Use of Potassium Fertilizers Sulfur Sulfur in Soils Sulfur and Its Oxidation Oxidation of Pyrites Assessing S Needs of Soil Sulfur Deficiency Symptoms in Plants Sulfur Needs of Crops Sulfur Fertilization Calcium and Magnesium Calcium and Magnesium in Soil Factors Affecting the Availability of Calcium and Magnesium in Soils Leaching of Calcium and Magnesium Determining Available Calcium and Magnesium Calcium and Magnesium Deficiency Symptoms Calcium and Magnesium Amendments Iron and Manganese Amounts and Forms of Iron and Manganese Soil Solution Iron and Manganese Factors Affecting Iron and Manganese Availability Soil Tests for Iron and Manganese Deficiency Symptoms of Iron and Manganese Toxicity Symptoms of Iron and Manganese Iron and Manganese Fertilizers Copper and Zinc Amounts in Soil Forms of Copper and Zinc in Soils Factors Affecting the Availability of Copper and Zinc Soil Tests for Copper and Zinc Deficiency Symptoms in Plants Copper and Zinc Fertilizers Boron and Molybdenum Boron Molybdenum Chlorine Chlorine in Soils Addition of Chlorine to Soils Testing Soils for Chlorine Deficiency Chlorine Deficiency Symptoms Chlorine Toxicity Symptoms Interactions with Other Nutrients Chlorides and Plant Diseases Crop Responses to Chloride Fertilization Chloride Fertilizers Beneficial Elements Sodium Silicon Cobalt Nickel Aluminum Vanadium, Lanthanum, and Cerium Nutrient Interactions Interactions Interactions of Primary Macronutrients Interactions of Micronutrients Organic Manures Crop Residues Animal Manures Composting Organic Farming Integrated Nutrient Management Cropping Systems, Soil Fertility, and Fertilizer Use Legumes in Crop Rotations Intercropping Systems Intensive Cropping Systems and Soil Fertility Fertilizer Application in Cropping Systems Index Each chapter contains References. NTI Copy (already approved)


Archive | 1991

Crop Residue Management

Rajendra Prasad; J. F. Power

In less affluent countries such as those in South and Southeast Asia, grain is directly used for human consumption, and crop residues are the main source of fodder for animals. In addition, crop residues have several other uses (Table 1). Crop residues are certainly an asset in these countries and seldom are left in the field. In advanced countries (Europe and America), draft animals have been replaced by internal combustion engines for farm power, and farmyard manure has been replaced by chemical fertilizer as a major source of nutrients. The development of synthetic fiber and a variety of inexpensive synthetic materials has replaced cereal straw for basketing, packaging, millinery, mat making, and similar uses (Staniforth, 1979). Consequently, with widespread use of combine harvesters, crop residues largely remain in the field and must be managed to provide the greatest advantage possible, especially for water conservation, erosion control, and maintenance of soil organic matter. In 1985, 918.58 million tons of cereal grain was produced in the developed world (Table 2), indicating that cereal residue production probably exceeded 1000 million tons per annum.


Soil & Tillage Research | 1986

Crop residue effects on soil environment and dryland maize and soya bean production

J. F. Power; Wallace Wilhelm; John W. Doran

The research reported here provides data on the effects of crop residues on the surface of no-till soil upon the soil environment and resulting biological activity, including crop growth. For maize (Zea mays L.) and soya bean [Glycine max (L.) Merr.] production in eastern Nebraska, U.S.A. (4 years of data), increasing crop residue rate decreased maximum soil temperatures at the soil surface by at least 5°C, and generally increased soil water storage by at least 50 mm. Availability and uptake of nitrogen from the soil organic matter and applied fertilizers (and for soya bean from decomposition of crop residues) were increased by increasing the crop residue rate from 0 to 150% of the quantity left after grain harvest of the previous crop. Hardly any of the nitrogen in maize residues was used by the next crop. These changes in the soil environment resulted in less stress on crops produced on residue-covered soil than for those on bare soil. Consequently, each Mg ha−1 of crop residues on the soil surface increased grain and stover production by approximately 120 and 270 kg ha−1 for maize, and 90 and 300 kg ha−1 for soya bean, respectively. Results show that there are major direct crop growth benefits from leaving crop residues on the soil surface, in addition to cumulative benefits that may result from reduced erosion losses and enhanced soil organic-matter contents.


Renewable Agriculture and Food Systems | 1987

Legumes: Their potential role in agricultural production

J. F. Power

The energy crisis of the late 1970s has raised the question of the wisdom of depending upon fertilizer nitrogen as the primary source of N input into crop production systems. While present and past price structures have favored fertilizer-N over biologically fixed N, there are a number of other benefits of legumes in a cropping system in addition to their effects on N availability. Among these are less potential for environmental degradation and improved soil physical conditions and water relations, but it is difficult to assign economic value to many such benefits. In addition to the economics of the present price structure, disadvantages of using legumes could include reduced total production and increased need for livestock in a farming enterprise (these could be considered assets from some aspects). Legumes are presently used in shortterm rotation, such as corn-soybean, or in continuous corn with a legume winter cover crop. These systems are finding widespread use and offer the producer many benefits, as well as helping to solve several major environmental problems associated with N use in agriculture.


Renewable Agriculture and Food Systems | 1987

Alternative production systems to reduce nitrates in ground water

R.I. Papendick; L.F. Elliott; J. F. Power

Evidence indicates a strong positive relationship between increases in nitrogen fertilizer use on cropland and nitrate concentrations in shallow ground water. This raises concern about the fate and efficiency of nitrogen fertilizer with current farming practices. Approximately 50 percent of the nitrogen fertilizer applied may be recovered by agronomic crops and 35 percent or less removed in the harvested grain of a crop such as corn. The residual nitrogen is subject to loss by several processes, one being leaching from the crop root zone. Alternative production systems that provide ground water protection must give attention to improved management of nitrogen fertilizer and to practices that minimize the need for nitrogen fertilizer and reduce soil nitrate concentrations. Most important in nitrogen fertilizer management is to more closely match nitrogen availability in the soil with crop needs and to avoid over-fertilization. Nitrogen fertilizer use can be reduced by alternate cropping of low and high nitrogen-demanding crops, use of legumes in the crop rotation to fix nitrogen, and proper use of manures, crop residues, and other organic wastes. Residual nitrates in soil can be reduced by use of cover crops, nitrogen-scavenging crops in the rotation, and alternating shallow and deep-rooted crops. Conservation tillage alone as used with many conventional cropping systems will probably not change the current status of nitrate leaching. Practices used by organic farmers should be carefully studied as possible approaches for ground water protection and adaptation into conservation tillage systems for conserving soil and water resources.


Soil Science | 1983

Sodium movement in soil ― minespoil profiles: diffusion and convection

S. D. Merrill; E. J. Doering; J. F. Power; F. M. Sandoval

We studied the movement of sodium and other ions in sodic strip-mine spoils reclaimed by soil spreading. In columns containing two different soils placed over minespoil, both model calculations and measurements indicated that considerably more Na migrated upward by salt diffusion than by convective flow generated by soil-water evaporation. More Na movement occurred in columns without evaporation than in columns with evaporation: reduced water contents reduced diffusion, and very low minespoil hydraulic conductivity severely restricted convective flow. Application of column results and model calculations to field observations of salt movements in topsoil-covered minespoils under semiarid, continental climatic conditions indicated that salt diffusion is a significant mechanism for Na accumulation in soil, provided the spoil is highly dispersed and the necessary chemical gradient is present. However, these calculations and data both indicate that significant quantities of Na would diffuse only 10 to 15 cm upward in materials of this nature.


Soil Science | 2000

Agricultural accomplishments and impending concerns.

Brian J. Wienhold; J. F. Power; John W. Doran

The thin layer of soil on the earths surface performs many functions essential to life. Humankind has known of the importance of this resource for thousands of years, but formal study of soils began only in the 1800s using knowledge acquired in the basic sciences of physics, chemistry, and biology.


Journal of Range Management | 1988

Irrigation water for vegetation establishment.

R.E. Ries; F.M. Sandoval; J. F. Power

This research project was conducted to’ evaluate tbe use of irrigation water to supplement predpitation during establishment of perennhi for8ge plant communities on surf8ce mined hnds in the northern Great Plains. Tbe treatments included precipitation and 9 combinations of various quantities of medium and low quality water applied to 8 ci8y loam topsoii repi8ced over 8 loam minespoil. We measured the response to the added water of a seeded forage species mixture, volunteer weeds, and cb8nges in salinity and sodicity of the soil/spoil profile. All levels of irrigation, regardless of water quality, increased seeded species production, but decreased weed dry matter. One season of irrigation with medium or low qurlity water produced minimal changes in soil saiinity and sodicity. Someincrease in soil salinity and sodicity was observed when low quality water was added during the second season. Therefore, low quality water can be used beneficially to supplement precipitation for 1 or 2 seasons during the establisbment of perennial plant communities on moderntely permeable soil/spoil 8reas.


Soil Science Society of America Journal | 1993

Denitrification and the Dinitrogen/Nitrous Oxide Ratio as Affected by Soil Water, Available Carbon, and Nitrate

K. L. Weier; John W. Doran; J. F. Power; Daniel T. Walters


Journal of Environmental Quality | 1997

Nutrient, Carbon, and Mass Loss During Composting of Beef Cattle Feedlot Manure

Bahman Eghball; J. F. Power; John E. Gilley; John W. Doran

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John W. Doran

University of Nebraska–Lincoln

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Rajendra Prasad

University of Nebraska–Lincoln

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Wallace Wilhelm

University of Nebraska–Lincoln

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Bahman Eghball

University of Nebraska–Lincoln

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L.N. Mielke

University of Nebraska–Lincoln

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A. R. Mosier

Agricultural Research Service

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John E. Gilley

University of Nebraska–Lincoln

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Stephen D. Merrill

Agricultural Research Service

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Brian J. Wienhold

Agricultural Research Service

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Daniel T. Walters

University of Nebraska–Lincoln

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