tailieunhanh - Ebook Horse pasture management: Part 2

Part 2 book "Horse pasture management" includes content: Climate, weather, and plant hardiness; matching plant species to your environment, weather, and climate; managing manure, erosion, and water quality in and around horse pastures; fencing and watering systems; pasture related diseases and disorders; coexisting with wildlife; university of kentucky horse pasture evaluation program. | Chapter 12 Climate Weather and Plant Hardiness Paul Sharpe1 and Edward B. Rayburn2 1 University of Guelph Guelph ON Canada retired 2West Virginia University Extension Service Morgantown WV United States INTRODUCTION A pasture that is well suited and managed for horses should be composed of forages that are adapted to the region and soils where they are grown and tolerant of local weather and climate. Weather is the condition of the atmosphere at one place over a short time period and climate is a description of the weather at one place over a long time period. Weather is reported in absolute measurements while climate is expressed as averages or ranges. Measured elements of weather and climate include temperature humidity sunshine wind speed wind direction cloud cover barometric pressure precipitation rain hail sleet freezing rain snow ice pellets cloud cover and storms. Plants can be affected by low and high temperatures intensity and hours of sunshine wind and precipitation. This discussion will begin with solar radiation which determines the intensity and hours of sunshine temperatures and evaporation of water. This leads to humidity and cloud cover thus to uneven heating of air causing wind and differences in atmospheric barometric pressure. All of these things lead to precipitation which provides the water needed for the development and growth of plants. SOLAR RADIATION Potential solar radiation above the atmosphere on a horizontal surface is a function of latitude and day of the year. At ground level radiation is reduced by clouds and dust. Daily solar radiation peaks on June 21 summer solstice and reaches its lowest level on December 21 winter solstice in the northern hemisphere. In the southern hemisphere these dates are reversed. Because the earth s northesouth axis for rotation is tilted relative to its path around the sun the angle of the sun s rays changes predictably during each annual trip around the sun. Table shows the sun s .