Maya Culture生活日记网
To understand the ancient Mayan people who lived in the area that is today southern Mexico and Central America and the ecological difficulties they faced, one must first consider their environment, which we think of as “jungle" or ’tropical rainforest." This view is inaccurate,and the reason proves to be important. Properly speaking, tropical rainforests grow in high-rainfall equatorial areas that remain wet or humid all year round. But the Maya homeland lies more than sixteen hundred kilometers from the equator, at latitudes 17 to 22 degrees north,in a habitat termed a “seasonal tropical forest." That is, while there does tend to be a rainy
season from May to October, there is also a dry season from January through April. If onefocuses on the wet months, one calls the Maya homeland a "seasonal tropical forest"; if onefocuses on the dry months, one could instead describe it as a "seasonal desert.”
From north to south in the Yucatan Peninsula, where the Maya lived, rainfall ranges from18 to 100 inches (457 to 2,540 millimeters) per year, and the soils become thicker, so that thesouthern peninsula was agriculturally more productive and supported denser populations. But rainfall in the Maya homeland is unpredictably variable between years; some recent years havehad three or four times more rain than other years. As a result, modern farmers attempting togrow corn in the ancient Maya homelands have faced frequent crop failures, especially in the north. The ancient Maya were presumably more experienced and did better, but nevertheless they too must have faced risks of crop failures from droughts and hurricanes.
Although southem Maya areas received more rainfall than northern areas, problems ofwater were paradoxically more severe in the wet south. While that made things hard for
ancient Maya living in the south, it has also made things hard for modem archaeologists whohave difficulty understanding why ancient droughts caused igger problems in the wet souththan in the dry north. The likely explanation is that an area of underground freshwaterunderlies the Yucatan Peninsula, but surface elevation increases from north to south, so that asone moves south the land surface lies increasingly higher above the water table. In thenorthern peninsula the elevation is sufficiently low that the ancient Maya were able to reach thewater table at deep sinkholes called cenotes, or at deep caves. In low-elevation north coastalareas without sinkholes, the Maya would have been able to get down to the water table bydigging wells up to 75 feet (22 meters) deep. But much of the south lies too high above thewater table for cenotes or wells to reach down to it. Making matters worse, most of the Yucatan
Peninsula consists of karst, a porous sponge-like limestone terrain where rain runs straight intothe ground and where little or no surface water remains available.
How did those dense southern Maya populations deal with the resulting water problem? Itinitially surprises us that many of their cities were not built next to the rivers but instead on highterrain in rolling uplands. The explanation is that the Maya excavated depressions, or modifiednatural depressions, and then plugged up leaks in the karst by plastering the bottoms of thedepressions in order to create reservoirs, which collected rain from large plastered catchmentbasins and stored it for use in the dry season.For example, reservoirs at the Maya city of Tikal 13held enough water to meet the drinking water needs of about 10,000 people for a period of 18months. At the city of Coba the Maya built dikes around a lake in order to raise its level andmake their water supply more reliable. But the inhabitants of Tikal and other cities dependenton reservoirs for drinking water would still have been in deep trouble if 18 months passedwithout rain in a prolonged drought. A shorter drought in which they exhausted their storedfood supplies might already have gotten them in deep trouble, because growing crops requiredrain rather than reservoirs.
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