tailieunhanh - AGRICULTURAL NONPOINT SOURCE POLLUTION: Watershed Management and Hydrology - Chapter 6

Con người đã sử dụng động vật cho lương thực và là một nguồn lao động trong suốt lịch Năm 1960 và 1970, đã có những thay đổi lớn trong chăn nuôi và sản xuất gia cầm. như nhu cầu tiêu dùng cho các sản phẩm thịt và động vật tăng lên, như vậy cũng đã cơ giới hóa sản xuất. Có một xu hướng lớn theo hướng sản xuất ở trại giam, chăn nuôi gia súc và gia cầm. Gà thịt gia cầm và các lớp dẫn đầu với nhà ở hệ thống với số lượng ngày càng lớn của động vật. Feedlots. | 6 Nonpoint Source Pollution and Livestock Manure Management W. F. Ritter CONTENTS Introduction Manure Characteristics Water Quality Impacts Sources Organic Matter Nutrients Microorganisms Salts Barnyard and Feedlot Runoff Manure Storage and Treatment Land Application of Manures Application Methods Surface Water Quality Subsurface Drainage Water Quality Groundwater Quality Practices to Reduce Nonpoint Source Pollution Barnyard and Feedlot Runoff Manure Storage and Treatment Systems Land Application Application Timing Application Rate Realistic Crop Yield Goals Soil Testing for Residual Nutrients Manure Testing Calibrating Manure Spreading Equipment Early Season Soil and Plant Nitrate Tests Nitrification Inhibitors 2001 by CRC Press LLC Winter Cover Crops Alfalfa as a Nutrient Scavenging Crop Alteration of Feed Alum Addition Livestock Grazing Impacts Summary References INTRODUCTION Man has used animals for food and as a source of labor throughout history. In the 1960s and 1970s there were major changes in livestock and poultry production. As the consumer demand for meat and animal products increased so also did mechanization of production. There was a major trend toward the production of confinement livestock and poultry. Poultry broilers and layers led the way with housing systems with increasingly large numbers of animals. Large beef cattle feedlots became common in the 1960s. With the introduction of confinement facilities and the increase in livestock and poultry in individual enterprises the quantity of manure to be disposed of became a problem. During the late 1960s and 1970s livestock waste management evolved as a field of engineering to protect the environment and make livestock production systems more cost effective. Overcash et summarized the .