The texture of the soil depends on the
relative amounts of different-sized particles that combine to make up the soil.
These particles can be as large as stone and gravel or as small as
clay. A typical clay soil is composed of approximately 60 percent actual clay, 20 percent silt, and 20 percent sand. The particles in a sandy soil are so fine that it tends to be compact and interferes with the oxygen supply for plant roots. Water has trouble entering this impervious soil, and runoff is very common during rainfalls. A typical light sandy soil is composed of approximately 70 percent sand, 20 percent silt, and 10 percent clay. The particles in a sandy soil are comparatively large, permitting water to enter the soil and to pass through it so quickly that it often carries nutrients with it and dries out very rapidly. The texture of A. To tell gardeners how to modify their soil. B. To classify soil types on the basis of their composition. C. To illustrate the effects of soil type on plant growth. D. To show how water is absorbed by different soil. [简答题]soil alkalization
[简答题]
SOIL QUALITY 1 Soil is a renewable resource, but only on a very long time scale, as it takes hundreds or thousands of years for the natural processes of erosion, organic decay, and accumulation to create soils.Soil quality and the potential to produce crops can vary enormously from region to region and among various soil types. 2 One important factor affecting the productivity of soils ever time is agriculture.Top-quality lands are brought into production earlier because of their higher potential to produce food.As more and more land has been brought under agricultural production, the average quality of land has decreased, reducing potential productivity per hectare.Crops deplete soil fertility by consuming nutrients, and this eventually reduces crop yields.Poor management practices lead to soil compaction and soil pollution as well as loss of soil cover.Without proper management and the constant addition of nutrients and e [单项选择]
SOIL QUALITY 1 Soil is a renewable resource, but only on a very long time scale, as it takes hundreds or thousands of years for the natural processes of erosion, organic decay, and accumulation to create soils.Soil quality and the potential to produce crops can vary enormously from region to region and among various soil types. 2 One important factor affecting the productivity of soils ever time is agriculture.Top-quality lands are brought into production earlier because of their higher potential to produce food.As more and more land has been brought under agricultural production, the average quality of land has decreased, reducing potential productivity per hectare.Crops deplete soil fertility by consuming nutrients, and this eventually reduces crop yields.Poor management practices lead to soil compaction and soil pollution as well as loss of soil cover.Without proper management and the constant addition of nutrients and energ A. world B. practices C. pressure D. soil 我来回答: 提交
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