The current system has low productivity per acre. It is very input intensive, inefficient, and is subject to volatile price swings. It's only advantage is that it's highly mechanized, so you get economy of scale with high output per worker and per asset, but that mechanization in it's current form is a system that destroys arability(soil health) over time. So your returns over time degrade, but input costs are on a 40 year uptrend... It's a broken system.
There are food systems that are more labor intensive (less return per human and per asset) but you can produce more food more predictably at lower margins for the producers and higher prices for consumers, but the with more stable input and end-user costs. The three added (and in my opinion most important) side-effects of this system are higher quality food, more jobs, and IMPROVED fertility over time. These new systems use science as well. They were developed by ecologists, systems theorists, and soil microbiologists.
Credentials: (i'm the first son of a 6th generation land-owning family in the Mississippi Delta region of Arkansas.)
However, i've used plastic sheeting in my garden to keep the soil warm and incidentally block light from weeds.