Iron Cycling in Natural Systems: An Analysis of the Effects of Climate and Vegetation on Iron Concentration and Speciation

Abstract

Iron is an essential nutrient to plants, and the presence of iron in a system can affect the presence of other important elements. Studying the concentration and speciation of iron in the environment helps understand its bioavailability to plants and how it cycles through the environment. Samples were collected from three unique sites to determine the effects of different environmental factors on iron content in the soil. Natural mulch and soil samples were analyzed for bulk iron concentration, distribution of iron in decaying organic litter, and iron speciation. Iron in mulch samples was found to accumulate and form clusters as the litter decomposed. Mulch and soil samples contained a mixture of tetrahedrally and octahedrally coordinated iron, and a combination of ferrous and ferric iron. The ferrous iron content of samples from Alaska was relatively high compared to the other locations, California and New Jersey, but there was significant amounts of ferrous iron at each of the locations.