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The predicted spatial and temporal shifts in temperature and precipitation are
likely to result in diverse effects on crop productivity between different crops and
regions. Increased temperatures are expected to increase crop water demand,
which may lead to increased crop stress or reduced productivity. In certain areas,
however, the increased temperatures may increase productivity and extend the
length of growing season for some crops, particularly where supplementary irrigation is available or the duration or volume of rainfall received increases (such
as in the centre and north of the study region). Climate change is projected to
impact the distribution, timing and volume of rainfall, most notably showing a
delayed onset of rainfall season or reducing the mean precipitation received during the growing season.
These projected climate changes are likely to result in long-term changes to the
timing of various agricultural activities such as field preparation and sowing of seed.
In the southern and eastern parts of the study area, notably Huíla and south-east Bié,
climate change is expected to reduce precipitation across all months of the growing
season, which will reduce the productivity of traditional agricultural approaches and
force farmers to adopt new practices and crops. Drought-sensitive crops are likely
to be increasingly unreliable or unproductive in the latter areas. In contrast, the
central and northern extent of the study region is expected to benefit from increased
rainfall during the middle and late summer months, which may extend the growing
season or improve the yield potential of certain crops.
4.3.2 Effects of Climate Change on Distribution of Crop
Suitability
Changes in the total spatial extent of suitable area were calculated for both crops for
the period from the present to 2050. Figure 4.3 provides an example of the approach
used to depict spatial distribution of crop suitability, where the relative proportion
of each colour-shaded area indicates the spatial extent of each corresponding category of crop suitability. Modelled distribution of suitability for cassava and maize is
depicted in Figs. 4.4 and 4.5, respectively, where current distribution of crop suitability is depicted on the left, projected future distribution of suitability is depicted
on the right, and the anomalies (i.e. changes) between the two periods are depicted
in the centre.
4.3.2.1 Cassava
Cassava is an important contributor to the diet and livelihoods of Angola’s rural
farmers and urban consumers, and is a particularly efficient crop in terms of calories
generated per input cost. In addition, cassava is considered to be relatively tolerant
of low rainfall conditions, and is increasingly promoted as a climate-resilient crop
4 Large Scale Crop Suitability Assessment Under Future Climate Using the Ecocrop…
The predicted spatial and temporal shifts in temperature and precipitation are
likely to result in diverse effects on crop productivity between different crops and
regions. Increased temperatures are expected to increase crop water demand,
which may lead to increased crop stress or reduced productivity. In certain areas,
however, the increased temperatures may increase productivity and extend the
length of growing season for some crops, particularly where supplementary irrigation is available or the duration or volume of rainfall received increases (such
as in the centre and north of the study region). Climate change is projected to
impact the distribution, timing and volume of rainfall, most notably showing a
delayed onset of rainfall season or reducing the mean precipitation received during the growing season.
These projected climate changes are likely to result in long-term changes to the
timing of various agricultural activities such as field preparation and sowing of seed.
In the southern and eastern parts of the study area, notably Huíla and south-east Bié,
climate change is expected to reduce precipitation across all months of the growing
season, which will reduce the productivity of traditional agricultural approaches and
force farmers to adopt new practices and crops. Drought-sensitive crops are likely
to be increasingly unreliable or unproductive in the latter areas. In contrast, the
central and northern extent of the study region is expected to benefit from increased
rainfall during the middle and late summer months, which may extend the growing
season or improve the yield potential of certain crops.
4.3.2 Effects of Climate Change on Distribution of Crop
Suitability
Changes in the total spatial extent of suitable area were calculated for both crops for
the period from the present to 2050. Figure 4.3 provides an example of the approach
used to depict spatial distribution of crop suitability, where the relative proportion
of each colour-shaded area indicates the spatial extent of each corresponding category of crop suitability. Modelled distribution of suitability for cassava and maize is
depicted in Figs. 4.4 and 4.5, respectively, where current distribution of crop suitability is depicted on the left, projected future distribution of suitability is depicted
on the right, and the anomalies (i.e. changes) between the two periods are depicted
in the centre.
4.3.2.1 Cassava
Cassava is an important contributor to the diet and livelihoods of Angola’s rural
farmers and urban consumers, and is a particularly efficient crop in terms of calories
generated per input cost. In addition, cassava is considered to be relatively tolerant
of low rainfall conditions, and is increasingly promoted as a climate-resilient crop
4 Large Scale Crop Suitability Assessment Under Future Climate Using the Ecocrop…