Month: November 2018

Since its beginning more than 10,000 years ago, agriculture has created intense ecological damage. Some argue that soil degradation trumps all other human-induced impacts on our landscape. Plowing and planting significantly impacts the fertility and structure of soil. The plowing of land creates soil that helps crop grow, but water and wind easily carries away the precious topsoil. As a result, the fertile topsoil slowly disappears the more land is farmed, thereby making farming more difficult.

Ancient people involved in agriculture used various techniques to minimize this soil erosion. One such technology was terracing, a method of artificially flattening land for crop cultivation (Treacy). This allowed farmers to grow on hillsides and mountains, and not limited to floodplains as they had been before. Terracing arose independently across the globe and many ancient civilizations used this farming technique, including the Inca and Aztec (Sandor). Some studies date terracing as far back as the Chalcolithic era in modern-day Israel/Palestine (Gibson).

Many different styles of terraces exist. Important features of terraces include retaining walls that hold the soil, degrees of slope, and self-filling or hand-filled terraces. The horizontal fields created allowed for easier crop cultivation and irrigation on sloped areas (Treacy).

Historians argue that soil erosion was not the primary force driving farmers to begin terracing. Population growth, changing social and labor structures, trading, and irrigation are all factors that possibly encouraged the creation of terraces (Gibson, Rodriguez, Treacy). Because soil erosion creates subtle change to the landscape, historians believe that the first people to use terracing were not aware of its impact on the soil. Trying to pinpoint the primary reason for terracing often ignores the complex relationship between humans and the natural world, and casts aside the important social functions of terraces. Regardless of the reason for their creation, the benefits to soil health and erosion demonstrates terracing’s most important contribution to farming (Rodriguez).

Most of the research surrounding terracing focuses on how terracing impacts soil quality and finding the potential for indigenous practices like terracing to influence modern agriculture. Scientists estimate that 1.5 inches of topsoil disappears every year as a result of increased mechanization. To find solutions  to this, soil scientists and agronomists look to indigenous methods of farming, including terracing. There are dramatic changes in topsoil losses under terraced vs not terraced conditions. In one study, terraces decreased soil loss by 19 tons per hectare while in another study it decreased by 62 tons per hectare. As demonstrated by Dorren and Rey’s review of terracing, significant modern research being done on soil erosion and terracing. This ancient technology is reappearing to save our soil.

 

 

Word Count: 435

 

Galileo is considered the ‘father of the scientific method’ and the ‘father of modern science’, among other titles complimentary of his impact on our current perspective of the natural world. In this article, Caldwell delves into Galileo’s influence on people’s view of machines and power.

Before Galileo, machines were considered only in terms of their final purpose. Each machine was not thought of its individual parts, but of whether it milled grain or told time. People judged the quality of a machine based on the materials it was built out of, whether it served its purpose, and if it was interesting to some extent. Machines were viewed as a way of cheating the laws of nature, being able to get more output for less input.

Galileo introduced a few ideas that changed this outlook. First, that machines had more in common with each other than was thought. He was able to show that machines could be reduced to simple levers (Fig 1). Another important concept was that machines were an economic utility – they reduced the amount of human labor in ways that were meaningful. From this idea, the quantification of power was put forth. A measurement for energy and human labor had never been before considered or needed. In modern day, knowing the power a machine is capable of producing is a normal necessity.

Figure 1