How does application of wood charcoal ash affect on crop yeilds, soil carbon sequestration and soil greenhouse gas emissions in different types of agricultural lands?

Wood charcoal has been used for cooking in Ethiopia and wood charcoal ash (leftover after burning) is simply dumped nearby house after using it.  It causes environmental problems and health issues. 

How about applying wood charcoal ash mixed with organic fertilizer (i.e., manure) and inorganic fertilizer (i.e., urea) in the crop fields (sugarcane and maize), grazing pasture, shade coffee agroforestry? 

How does the application affect crop yields? 

How does the application affect soil carbon sequestration in the fields? 

How does the application affect soil greenhouse gas emissions? 

Figure 1. Wood charcoal before using

 

 Figure 2. Wood charcoal after using

 Figure 3. Abandoned used wood charcoal in back yard

Effects of conversion of natural forest to shade coffee agroforestry, grazing pasture and crop fields on soil carbon sequestration and soil carbon dioxide emissions, Wondo Genet, Ethiopia

Natural forest is converted to different land-use types such as agroforestry, grazing pasture and crop fields. How does the conversion affect soil carbon sequestration? How does the conversion affect soil CO2 greenhouse gas emissions? 

1. Natural forest at Wondo Genet College of Forestry and Natural Resources

2. Shade coffee agroforestry at Wondo Genet College of Forestry and Natural Resources

3. Grazing pasture at Wondo Genet College of Forestry and Natural Resources

4. Maize fields at Wondo Genet College of Forestry and Natural Resources

5. Over-view of Wondo Genet College of Forestry and Natural Resources

Yield-scaled direct nitrous oxide emissions in organic and inorganic fertilizers applied sugarcane and maize cropping system, Wondo Genet, Southern Ethiopia

How much nitrous oxide (N2O) is produced from organic fertilizer? How much N2O is produced from inorganic fertilizer? Are the amounts significantly different? What is the optimum amount of fertilizer and fertilizer type producing less N2O with high yields? 

How does expansion of bush encroachment affect soil carbon sequestration and soil greenhouse gas carbon dioxide emissions in the Borena pastoral system, Ethiopia?

The Borana rangeland, Southern Ethiopia was productive grazing areas. However, bush-tree cover has become dominant in the rangeland mainly due to fire band and climate change. How does the expansion of bush encroachment affect soil carbon sequestration and soil greenhouse gas carbon dioxide emissions? Does it provide benefit for soil fertility and global climate through increasing soil carbon sequestration? Or does it provide problems for soil fertility and global climate through decreasing soil carbon sequestration and increasing soil carbon dioxide greenhouse gas emissions?

 Photo source: http://savingstripes.wildlifedirect.org/category/rangeland-management/

 

How is net gain of soil carbon in indigenous Ethiopian home gardens compared to that in mono-culture crop fields?

Ethiopian home gardens are a sustainable traditional agroforesty system that grows crops such as ensete (Ensete ventricosum) and coffee (Coffea arabica) that can coexist with various tree species to provide households with food, fuel and cash income, while protecting the soil and biodiversity. They can also enhance resilience to drought and contribute to mitigating climate change by enhancing soil carbon (C) sequestration. Soil C sequestration can provide additional economic benefits to communities by providing them carbon credits that can be traded in the global carbon market. By quantifying soil C sequestration as soil C gain and soil carbon dioxide (CO₂) emissions as soil C loss in these sites, this study can determine the net gain of soil C in home gardens compared to that in mono-culture crop fields. 

How is net gain of soil carbon in tree-crop intercropping systems in sub-Saharan Africa compared to that in mono-culture crop fields?

Tree and crop intercropping systems are both indigenous and introduced agroforestry systems common in sub-Saharan Africa. The intercropping systems can enhance soil organic matter, and thereby carbon (C) sequestration, can increase resilience to drought in sub-Saharan Africa, and contribute to mitigating climate change. Also soil C sequestration can provide additional economic benefits to agricultural communities through C trading schemes. However, due to a lack of information on C gain from soil C sequestration and C loss from greenhouse gas (GHG) carbon dioxide (CO₂) emissions in intercropping systems, it is difficult to accurately quantify net soil C gain. This adds to the difficulties in soil C trading for local agricultural communities and uncertainties in global GHG research. In this proposed study, through quantifying soil C sequestration and soil CO₂ emissions, the gain in net soil C will be determined in established intercropping systems in Ethiopia, Uganda and Malawi combined with on farm demonstration projects for local communities and extension staff. 

 

Figure. After harvesting corn in Faidherbia-corn intercropping field, Malawi (Provided by Tracy Beedy, World Agroforestry Center) 

Lake Awassa in Ethiopia, Source of greenhouse gas nitrous oxide?

A lake in a fast growing city ‘Awass, Ethiopia’. Nutrients input from fish market, textile factories, hotels and restaurants nearby the lake and watershed. How is nitrogen level in water? How are nitrous oxide greenhouse gas emissions in the lake? Is the lake source of nitrous oxide?