Page 246 - Environment: The Science Behind the Stories

(a) Crop rotation (b) Contour farming

(c) Terracing (d) Intercropping

(e) Shelterbelts (f) No-till farming

Figure 9.15 Farmers have adopted various strategies to conserve soil. Rotating crops (a) such as
soybeans and corn helps restore soil nutrients and reduce impacts of pests. Contour farming (b) reduces
erosion on hillsides. Terracing (c) minimizes erosion in mountainous areas. Intercropping (d) reduces soil loss CHAPTER 9 • So I l AN d A gr I culT ure
and maintains soil fertility. Shelterbelts (e) protect against wind erosion. In (f), corn grows through the remnants
of a cover crop used in no-till agriculture.

the soil. Often a localized dose of fertilizer is added to the soil proponents of no-till farming credit the practice with a num-
along with the seed. ber of benefits (Table 9.1). One benefit that looms larger and
By increasing organic matter and soil biota while reduc- larger is that of carbon storage (pp. 526, 555–556). To miti-
ing erosion, no-till farming and conservation tillage can gate global climate change (Chapter 18), we must find ways
restore soil quality. Based on results in Iowa and elsewhere, to reduce the atmospheric concentration of carbon dioxide. By
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