TEACHING ALL VOLUMES SUBMIT WORK SEARCH TIEE
Volume 6: Table of Contents TEACHING ISSUES AND EXPERIMENTS IN ECOLOGY
ISSUES: FIGURE SETS

Figure Set 5: Global Warming Potential - Temperate Agriculture

Purpose: To teach students that land management can affect the amount of greenhouse gas emissions from temperate agricultural production and that cessation of agriculture results in net sequestration of greenhouse gases in the soil. Students will play roles of various citizen groups to identify ways in which agricultural land management can affect a variety of different people around the world.
Teaching Approach: Citizens Argument
Cognitive Skills: (see Bloom's Taxonomy) - Knowledge, interpretation, analysis, synthesis
Student Assessment: Land Management Activity

FIGURE SET

Ecosystem Management
CO2
N2O
CH4
Net GWP
Soil C
N Fertilizer
Lime
Fuel
Conventional Agriculture
0
27
23
16
52
-4
114
No-Till Agriculture
-110
27
34
12
56
-5
14
Organic Agriculture
-29
0
0
19
56
-5
41
Early Successional
-220
0
0
0
15
-6
-211
Late Successional Forest
0
0
0
0
21
-25
-4
 

Table 5. Global warming potential (GWP), by greenhouse gas and by specific source of CO2, is shown for five different experimental ecosystems in a long-term ecological research (LTER) experiment in southwest Michigan. Each Ecosystem Management treatment was replicated six times on randomly selected one hectare plots. Positive numbers indicate net increase in global warming potential while negative numbers indicate a decrease in global warming potential. Annual crops were harvested for agricultural production while successional communities were left undisturbed, except for occasional burning of the Early Successional plots. This table is redrawn from Table 2 in Robertson et al. (2000), which is published in the journal 'Science.'

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