Agriculture Reference
In-Depth Information
TABLE 12.11
Annual Runoff Coefficient and Soil and Nutrient Loss under Different Land
Use Types in West Usambara Mountains, Tanzania, Measured on Runoff
Plots (
N
= 3)
Annual Runoff
Coefficient
(mm/mm/year)
Annual Soil
Loss
(Mg/ha/year)
Annual
Total N Loss
(kg/ha/year)
Annual
P Loss
(kg/ha/year)
Annual K
Loss (kg/
ha/year)
Treatment
Bare
0.15
a
169.0
a
464
a
0.6
a
10.77
a
Control
0.10
a
132.0
b
342
b
0.4
b
6.88
b
Miraba
0.04
c
0.7
c
9
c
0.1
c
0.02
c
Miraba
+ FYM +
mulching
0.03
c
0.5
c
9
c
<0.1
d
<0.02
c
Source:
Adapted from Msita, H.B. 2013. Insights into indigenous soil and water conservation technolo-
gies in Western Usambara Mountains, Tanzania. PhD thesis. KU Leuven, Belgium. p. 194. With
permission.
Note:
FYM, farmyard manure; Means with the same letter in columns are not significantly different by
Duncan multiple range test comparison, α = 0.05.
Miraba
= rectangular bound grass strip that does
not follow contour (an indigenous soil and water conservation technology on the sloping land of
Usambara Mountains Tanzania).
and higher in the long rainy season (Table 12.12). On the other hand, in
miraba
and
miraba
with FYM and mulching, soil losses are higher in the off-season and lower in
the short rainy season. The nutrient losses are lower in bare and control plots in the
short rainy season and higher in the long rainy season. On the other hand, in
miraba
and
miraba
with FYM and mulching, nutrient losses are higher in the off-season and
lower in the short rainy season. These results have demonstrated that
miraba
and
miraba
coupled with FYM and mulching are effective soil and water conservation
technologies for the tropical highlands of East Africa.
12.3
CONSERVATION AGRICULTURE IN EAST AFRICA
12.3.1 c
onservation
a
griculture
and
F
farming
P
ractices
Agriculture is a notable source of the major greenhouse gases: carbon dioxide, meth-
ane, and nitrous oxide (Commission of the European Communities Brussels 1996;
FAO 2010). Agricultural activities and land use changes contribute about one-third
of the total carbon dioxide emissions and are the largest sources of methane (from
livestock and flooded rice production) and nitrous oxide (primarily from application
of inorganic nitrogenous fertilizer). The Ecological Society of America (2000) pro-
vides a list of management techniques that improve agricultural land qualities that
consequently increase carbon sequestration. These techniques include the planting
of cover crops, mulch farming combined with zero tillage, and agroforestry. Some of
these practices would influence agricultural land qualities that increase aboveground
