eBusiness Weekly
This week we return to Great Zimbabwe but asking new questions about its available natural resources and how those influenced its development
.
What was the population of Great Zimbabwe?
Last time, we reviewed the theories on the possible size of the community that may have lived at Great Zimbabwe during its occupation.
The conclusion was that previous estimates of a massive, permanent population of 18,000 or more were unlikely. A more plausible total was between 2,500 to 4,000 people living in the city as its peak, with a concentrated community in the hinterland.
Certainly, this number would have fluctuated over time, most strongly influenced by the availability of certain essential raw materials and resources: water, wood, arable land and food.
The decline of Great Zimbabwe has often been explained by scholars as a consequence of the degradation of the environment caused by over-exploitation and climate change.
This idea needs to be re-examined in the light of this new thinking on the size of the population, an integrated economy and its potential impact on the area.
Water first then!
It has long been assumed that the people living at Great Zimbabwe simply extracted their water from the Muturikwi River and a couple of local springs without fully considering the awkward logistics involved with such endeavours.
The Muturikwi River is an average of 6.5km away from the site, a long distance to carry such a heavy material every day.
How could enough water be carried so far to meet the daily needs for drinking, cooking, washing and building? Could they store enough water for daily use? What about rainwater capture?
Modern research, spearheaded by various academics from Zimbabwe, Italy and South Africa are mapping the available sources of water in the landscape to answer these and other questions.
What have they discovered?
We await the full publication of their results but the preliminary findings are enticing. Simply put, there are many natural springs, aquifers, marshes, swamps, and shallow, seasonal wetlands in close proximity to the ancient city that could have been regularly exploited (see map).
Surprisingly, using satellite technology and detailed ground surveys, several small streams in and around the site have been identified for the first time, suggesting that the people of Great Zimbabwe enjoyed a wetter period in the climatic history of southern period.
Rainfall would have been more regular and plentiful than is currently the case and thus is is likely that water would have been fairly easily available. Finally the authors of the study tentatively suggest that the massive pits at the base of the Hill Complex (see map) were not, as as long been claimed, clay quarries for house construction. Rather they argue that these were reservoirs dug in the heart of the city as a convenient, semi-permanent source of water.
Could that be true?
More research on the pits is certainly required but the hypothesis of water storage is enticing. The geology and soil tests show the pits are capable of holding water.
Oral traditions and myths in the area point to these holes holding water for long periods of time after the rains finished.
Some local community members have even reported hearing that their ancestors used to catch fish in the pools; success was guaranteed only as long as one ate all that was caught before returning, otherwise all the fish caught would spoil. There are also many written accounts from early visitors in the 1890s of the holes filling with water and swamp-like conditions prevailing in the vicinity of Great Zimbabwe hinting at how the availability of water has changed.
Does the vegetation tell us anything about water?
A recent thesis by UZ alumni Joseph Chikumbirike conducting studies on charcoal from excavations at the site as well as the modern vegetation has much to tell us about the past climate and environment around Great Zimbabwe.
The results showed that at least 30 wood species were exploited when the site was occupied at Great Zimbabwe. The study showed that the past woodlands were typical miombo woodlands, similar to today.
The species composition in the archaeological record thus suggests that significant climate change did not occur at the fall of Great Zimbabwe in 1550AD. Interestingly most of the taxa exploited indicate a riverine habitat thus contributing to the idea that some of the areas around Great Zimbabwe had an uplifted water table. It can also be concluded that the inhabitants of Great Zimbabwe had access to wet patches such as swamps or permanent water bodies.
Anything more?
Certain tree species were used in different parts of Great Zimbabwe. For example the use of mopane was confined to the Great Enclosure and the Hill Complex.
The hook-thorn Acacia (chikwaku or umdwadwa) was commonly found in the archaeological record but surprisingly does not occur today. Perhaps it no longer grows in the immediate area due to over-exploitation by the people at Great Zimbabwe as firewood; the saplings are favoured by browsing animals.
The sickle-bush (mubayamhondoro or igaku) was found in five different areas of the site linked with metal smelting. The tree re-sprouts rapidly after cutting and is an excellent firewood that burns slowly, perfect for firing a furnace.
The African sandalwood (munhiti or ubande) is one of the rarest woods in the charcoal of Great Zimbabwe but it sheds light on cultural selection and possible past trade in favoured woods. Today it neither grows at Great Zimbabwe nor within its vicinity but was used extensively as door lintels around the site, suggesting it was specially brought in over hundreds of kilometres, probably from the Lowveld.
Could droughts have played a role in GZ’s demise?
Regrettably we do not yet have enough information about what the fluctuations in the climate during the years Great Zimbabwe reigned supreme, from 1250 to 1550AD. It is certainly possible that droughts and periods of aridity occurred in the past and would have had an effect on the settlements of the time. As today, people would have developed various strategies to cope and in the pottery assemblages (collections) discovered at Great Zimbabwe and related sites are often remains of large pots that may have been used to store water (chirongo) when the traditional springs and wells dried up.
There are important questions about the impact of such droughts on the vast herds of cattle that presumably formed the basis of the economy in the empire; how would people have coped with shrinking water sources as they struggled to preserve their herds?
Would they have moved them to the south or north to be next to the larger rivers or would they have selectively slaughtered them to reduce numbers and thus pressure of water sources?
Could they have traded their animals away or could there have even been the nationalisation of herds for the greater good? We may likely never know.
What does this all help us to understand?
The demise of Great Zimbabwe has been of interest to scholars ever since its existence was confirmed to the outside world in 1871.
There are several theories which usually point to a single event or cause – ranging from famine, to environmental destruction, internal conflict and collapse of trade.
The new research being done is helping to reveal more about conditions at the time of Great Zimbabwe’s decline which will help us to refine our understanding of its decline and provide lessons for our future.
Fascinatingly there may be another factor behind the troubles experienced there: an increase in gold mining.
Portuguese documents point towards gold production becoming increasingly dominant within the economy from around 1500, which compromised other sectors of the economy – most importantly agriculture.
As more people stopped farming to go mining – for the better economic rewards in trade – food production stalled and when trade declined from 1515 to 1550 due to outside interference, this created huge socio-political stress.
Great Zimbabwe, already weakened by a drying climate, may have been unable to deal with this change, despite its rich trade networks.
Just what these were and how they functioned will be the focus of a future briefing.
