Southwest Agriculture

Southwest AgricultureAfter the arrival of hunter-gatherers in the southwestern region of NorthAmerica, several alternative types of agriculture emerged, all involvingdifferent solutions to the Southwest’s fundamental problem: how to obtainenough water to grow crops in an environment in which rainfall is so low andunpredictable that little or no farming is practiced there today. Peopleexperimented with alternative strategies for almost a thousand years indifferent locations, and many experiments succeeded for centuries,but eventually all except one succumbed to environmental problems causedby human impact or climate change.The word “eventually” in the passage is closest in meaning toA.some degreeB.unfortunatelyC.in the endD.graduallyParagraph 1 supports which of the following inferences about the NorthAmerican Southwest?A.Its sources of water were plentiful when the hunter-gathers firstarrived.B.It has always lacked the large population needed to performsuccessful experiments in agriculture.C.Its climatic conditions today are essentially similar to those existingwhen the hunter-gathers first arrived.D.It was more seriously affected by climate change than it was byhuman impact.One strategy was to live at higher elevations where rainfall was higher, as didthe Mogollon, the people at Mesa Verde, and the people of the earlyagricultural phase at Chaco Canyon known as the Pueblo I phase. But thatcarried a risk, because it is cooler at high than at low elevations, and in anespecially cool year, it might be too cold to grow crops at all. An oppositeextreme was to farm at the warmer low elevations, but there the rainfall isinsufficient even for dryland agriculture. [ ▇ ]The Hohokam got around thatproblem by constructing the most extreme irrigation system in the Americasoutside Peru. [▇]But irrigation entailed the risk that human digging of ditchesand canals could lead to sudden heavy water runoff from rainstorms, diggingfurther down into the ditches and canals and carving out deep channels calledarroyos. [ ▇ ]In that case, the water level would drop below the field level,making irrigation impossible for people without pumps. [▇]All of the following are mentioned in paragraph 2 as potential problems facedby the Hohokam EXCEPTA.insufficient rainfall to allow crops to growB.rainstorms leading to destructive water runoffC.insufficient workers to dig ditches and canalsD.irrigation water levels in channels too low to be usedLook at the four squares[▇]that indicate where the following sentence couldbe added to the passage. Where would the sentence best fit?Another risk of irrigation was that floods could simply wash away thedams and channels, as indeed may have happened eventually to theHohokam.A more conservative strategy was to plant crops only in areas with reliablesprings and groundwater tables. That was the solution initially adopted by theMimbre...