11 18 2013 GY339 Exam 2 Shelterbelt program main objective was to reduce wind speeds by putting in a physical barrier If you slow wind speeds you limit what it can pick up which reduces soil erosion Each shelter belt is made up of rows of trees with varying heights and planted perpendicular to the prevailing wind The benefits of the shelterbelt include soil moisture losses a habitat to wildlife that wasn t there before better water retention and most of the first ones were conifers which provided year round protection After the shelterbelt program was put into place wind speeds were reduced by 8 to 30 mph which is very significant in terms of sediment transport Difference between alternative and sustainable Alternative agriculture is any type of farming that is different that the norm Sustainable agriculture means that we are conserving soil and using it in a way that it will be there for future generations Types of alternative agriculture include biodynamic integrated systems low input natural systems and no till Although the methods of each alternative method differ all are leaning toward a more natural way of growing Sustainable agriculture is designed to produce sufficient yield and high quality is environmentally safe economically viable conserve resources and ensure social responsibility Ideally we want to grow sustainably but barriers we are faced with include no federal incentive to diversify older farmers who are set in their ways and the Freedom to Farm Act which promotes growing a single crop 3 classes of pesticides The three classes of pesticides include Chlorinated hydrocarbons Organic Phosphates and Carbamates DDT is a Chlorinated hydrocarbon which is fat soluble breaks down the central nervous system in humans and biomagnifies Although Organic phosphates are water soluble and seemed to be a better option than Chlorinated hydrocarbons they can cause damage to the nervous system Carbamates such as Sevin dust are biodegradable and a person can eat food treated with it after 7 days The gypsy moth was brought from France to Massachusetts intentionally to develop a disease resistant silkworm A few escaped and had no predator so they multiplied rapidly Gypsy moths eat away trees and have now spread throughout the country The dutch elm disease was imported to the U S The actual disease doesn t kill the tree However the tree s attempt to prevent the spread of the disease is what actually kills the tree since it stops flow of water Classification of wetlands Wetlands and Deep water habitats o Marine o Estuarine o Riverine Riparian zones and wetlands o Lacustrine lakes o Palustrine just wetlands Watershed management approach has to work better than any other because it is defined by nature In order to manage this resource we must manage the land around it The components of a watershed plan include preventing conflicts and disputes in a watershed protecting water resources and aquatic ecosystems regulating in stream flows and ensuring that water is not being wasted In terms of management this is the way of the future This approach works so well because it is voluntary However in order for this approach to work the overall goals must be the same everyone must be in agreement that we need to best water quality at the lowest price possible soil dynamic and very responsive to changes in the environment Why is soil so important Soil is important for plant growth and acts as a buffer for water and filtration It can filter out harmful contaminants in our air prevent erosion and acts as a sponge by trapping harmful contaminants The ideal water holding capacity is field capacity There is enough water but still room for air to move Soil should be treated as if it were nonrenewable because the rate at which it is depleted can exceed the rate at which it is generated Soil is a vulnerable product of natural processes and it takes 500 years to get 1 layer of topsoil All soil types are divided into 12 main orders Mollisols have a high natural fertility and are the most productive soils Although Mollisols produce the most agricultural crops these soils don t do very well once we take the native vegetation away The ideal soil conservation method is to cultivate it while causing the least disturbance to it Alabama has minimal invasive operations and is at the top of no till agriculture Erosion is a natural process but can be accelerated by poor soil management The Grand Canyon was formed as a result of natural erosion but accelerated erosion usually occurs on farmed land its natural vegetation has been removed Soil that has been disturbed is more vulnerable to movement and an average rainfall event could remove its most fertile layer Erosion which is primarily caused by wind and water is still a major problem today There are 30 000 conservation districts and billions of tax dollars are invested in preventing erosion which are making a difference Today there is more acreage under cultivation than in the 1930 s but there is an overall decreasing trend in erosion on cropland The dust bowl marked a time where we first realized how important and vulnerable soil is Following the dust bowl the soil conservation service was established The Dust Bowl was caused by a combination of poor agricultural practices and climate change Prior to the Dust Bowl native grasses were cleared and replaced by farmland The grass roots which previously held the soil in place were no longer there exposing countless acres to wind erosion When this area experienced a drought followed by wind storms the soil had nothing holding it in place like before and was vulnerable to movement The effects of the Dust Bowl were seen across the country The wind blew the dust to the East which left sand in areas which depended on fertile soil for agriculture Following the Dust Bowl of the 1930 s programs designed to prevent soil erosion were put into place which also created jobs during the Great Depression What programs were set in place The main objective of the Shelterbelt Program of 1935 was to reduce wind speeds by putting in a physical barrier Soil Conservation Service Watershed plan Watershed management approach has to work better than any other because it is defined by nature In order to manage this resource we must manage the land around it The components of a watershed plan include preventing conflicts and disputes in a watershed protecting water resources and aquatic ecosystems regulating in stream flows and ensuring that water