ASSIGNMENT

[amos ouma]

URBAN SYSTEM AND ECOSYSTEMS
Urban systems are centered in urban areas (which are primarily sites
of consumptions in terms of ecosystem). Urban systems can be
identified with individual urban settlements or networks of such
settlements. It is worth noting that half of world’s population lives
in urban areas
Within the urban areas, the primary issue from the perspective of
human well-being is whether the urban settlements provide a healthy
and satisfying living environment for the residents. Urban development
can easily threaten the quality of the air, the quality and
availability of water, the waste processing and recycling systems.
Certain groups (such as low-income residents) are particularly
vulnerable to these threats. At the second scale, when urban
development harms ecosystems in the surrounding region, there are more
extensive issues of spatial injustice. The third scale involves
burdens that urban activities impose on distant people and future
generation by reducing their access to ecosystem services, either
because these systems are diverted to urban uses or because the
ecosystems themselves are degraded, raising issues of spatial justice
as well as issues of temporal justice.
It is also important to note the linkage between the urban areas and
the rural hinterland. Agriculture practiced within urban boundaries,
for example, contributes significantly to food security in urban areas
especially in sub-Saharan Africa. People from the rural hinterland
also provide market for the industrially manufactured goods from the
urban areas. The intensity of the interaction between an urban system
and its surroundings tends to fall off with increasing distance.
Interaction also tends to be more intense along certain corridors
(such as rivers and rocks) and within environmentally bounded areas
such as watersheds. Since most urban centers are growing in population
and extent, the peri-urban areas where the systems adjoining urban
systems are located are also undergoing transformation, with arable
land coming under increasingly intense cultivation and both arable and
non-arable land increasingly built over to provide space for
commercial, industrial and residential establishments and for roads
and parking facilities. The more populated an urban area is the
greater its influence is likely to be on the surrounding areas.