Nutrients into Soils: Part 1
Updated: Mar 23
Organisms use nutrients for growth, repair, and reproduction. Plants uptake essential nutrients from soil. Nutritious soils which can maintain plant growth in suitable environmental conditions are classified as fertile. Minerals are inorganic elements and compounds which form under numerous geological environments. Minerals are an essential nutrient.
Three common types of forests include: temperate, tropical and boreal forests. Temperate forests go through the four seasons. Tropical forests are rich in biodiversity and their temperature remains relatively high. Boreal forests are commonly in cold climates. Flora grown here is predominantly coniferous trees.
Deciduous and coniferous trees influence the soil they grow in (Figure 1). Temperate forests containing deciduous trees produce approximately 36 % of leaf litter compared to coniferous forests (Adams et al., 2019). Deciduous forests have a fine layer of organic matter (Wunderlich et al., 2019). Their leaf litter decomposes at a quicker rate compared to coniferous forest litter. Organo-mineral interactions play a role in stabilisingsoil organic matter. Over a year, evergreen leaves have a higher water storage capacity and rate of evapotranspiration, compared to deciduous leaves. In turn, less water reaches the soil below, altering the biological properties. In conifer forests, fungi dominate over bacteria in biomass quantity (Adams et al., 2019). Burgess-Conforti et al. (2019) found that the pH of topsoil did not differ underneath coniferous or deciduous trees, though a higher acidity was found in coniferous litter.
Broadleaf trees have been found to have a greater soil C:N ratio compared to coniferous trees, in turn, altering the soil microorganisms which can thrive (Wan et al., 2015). For both forest covers, microorganisms were more strongly associated by carbon allocation from roots compared to leaf litter contributions. (Wan et al., 2015). Carbon allocation is the transfer of carbon from the atmosphere to the roots as photosynthates. On a local scale, forests of different tree species have not been found to differ in carbon dioxide effluxes (Wunderlich et al., 2019).
Grassland has a large coverage of plant biomass. Soil organic matter is mineralised to form ammonium, then nitrified to form nitrates which are an available source of nitrogen for plants. Grass species are commonly perennial and can withstand the grazing from livestock (Ghosh et al., 2014). Soils are a large source of carbon; management of pasture can help maintain and improve carbon storage.
Silvopasture is land made up of both pasture and forestry for livestock grazing. This land use has been found to have a greater carbon sequestration compared to solely pasture and agricultural land (Mangalassery et al., 2014).
In the next blog:
Authenticae will explain the soil types that play a role in the fertility of forests and pasture. In future blogs, rainforests with low and high fertility contents will be discussed, along with the nutrients within pasture.
Adams, M.B., Kelly, C., Kabrick, J. and Schuler, J., 2019. Temperate forests and soils. In Developments in Soil Science, 36, pp. 83-108
Burgess-Conforti, J.R., Moore, P.A., Owens, P.R., Miller, D.M., Ashworth, A.J., Hays, P.D., Evans-White, M.A. and Anderson, K.R., 2019. Are soils beneath coniferous tree stands more acidic than soils beneath deciduous tree stands? Environmental Science and Pollution Research, 26(15), pp.14920-14929.
Ghosh, P.K., Mahanta, S.K., S.N. Ram, S.N., 2017. 13 - Nitrogen Dynamics in Grasslands. The Indian Nitrogen Assessment, pp. 187-205
Mangalassery, S., Dayal, D., Meena, S.L. and Ram, B., 2014. Carbon sequestration in agroforestry and pasture systems in arid north-western India. Current science, pp.1290-1293.
Wan, X., Huang, Z., He, Z., Yu, Z., Wang, M., Davis, M.R. and Yang, Y., 2015. Soil C: N ratio is the major determinant of soil microbial community structure in subtropical coniferous and broadleaf forest plantations. Plant and soil, 387(1), pp.103-116.
Wunderlich, S., Schulz, C., Grimmeisen, W. and Borken, W., 2012. Carbon fluxes in coniferous and deciduous forest soils. Plant and soil, 357(1), pp.355-368.