Download Agriculture: The Food We Grow and Animals We Raise (Natural by Julie Kerr Casper PDF

By Julie Kerr Casper

Explores some of the most vital makes use of of the land: the creation of agriculture. This e-book is helping readers study that farms and ranches produce even more than foodstuff; yet scientists, farmers, ranchers, and different landowners have not solved conservation difficulties - but.

Show description

Read Online or Download Agriculture: The Food We Grow and Animals We Raise (Natural Resources) PDF

Best science studies books

So What About Soil?: A Book About Form and Function

Discusses the significance Of Soil, Soil elements, Its Attributes, And Examples together with Sand, Clay, And Silt.

Spits and Squirts: How Animals Squirt to Survive

This sequence explains the behaviors, diversifications, and features of various life-forms in several environments.

Additional resources for Agriculture: The Food We Grow and Animals We Raise (Natural Resources)

Sample text

The only way to untangle the chain is to trace a specific food chain back to its source. Food webs are critical in agriculture, both in cultivating crops in fields, and in grazing animals on rangelands. They are also very complex, and like most complex, interconnected systems, the whole is greater than the sum of its parts—if the parts are removed, the system disintegrates. In the food web, if key organisms or multiple groups disappear, the web may collapse. As food chains move from soils, to plants, to animals, to humans, it is not hard to see why maintaining a working system is important.

In this example, grass is at the bottom of the food chain, and the eagle is at the top (assuming nothing eats the eagle). The real world is much more complex than a simple food chain, however. There might be a few organisms whose diet includes only one item, but that is not usually the case. For example, the eagle eats snakes, but it also eats many other things (squirrels, rodents, and rabbits), and those other things are part of food chains as well. A more complex and realistic way of looking at these processes is through a food web.

Early civilizations that recognized the disastrous effects of erosion used devices such as terracing the land to keep from plowing, planting, and irrigating on hillside slopes where water could wash the fertile soil away. There are many causes of erosion. It can occur by wind, water, drought, overfarming, lack of ground cover, and overgrazing. Erosion by wind is worse in arid and semiarid areas. It removes soil and natural vegetation and causes dryness and deterioration of the soil structure. Water erosion is greatest when heavy rainstorms fall on land that is unprotected by vegetation.

Download PDF sample

Rated 4.14 of 5 – based on 39 votes