A study published in January 2020 says that due to the changing climate, a shift in phenology can happen. It is a schedule or lifecycle of plants and living things such as when they first bud, leaf, flower or fruit.
Using satellite data researchers have observed an early spring greening occurring in the Northern Hemispheres. The emergence of early spring can increase carbon uptake that leads to more productivity in plants hence the increased foliage cover in the Northern Hemisphere that researchers have documented between 1982 and 2011.
Early spring greening can also increase evapotranspiration, a process when plants draw in water from the soil and transport it to the atmosphere. Increased and prolonged evapotranspiration activity in spring may lead to drier soils in the summer, as climate simulation and direct observation shows.
Drier soils also reduce the cooling effect of evaporation which can usher into more intense heatwaves in the summer and altogether reduces ecosystem productivity and restrain vegetation, especially for water-sensitive plants.
Researchers have also observed a teleconnection phenomenon occurring. For example, the moisture that is sucked in the vegetation in Europe in spring is transported to Siberia in the form of rain the following summer which can offset soil drying from early greening.
This finding is important as it can produce an accurate prediction of soil moisture and climate conditions in the summer of a local region based on direct links from large scale atmospheric patterns and soil moisture in a local region as observed by researchers of the study.
Soil moisture levels in deeply rooted plants were not included in the study as it is not directly measured at large scale levels and there are differences in estimates in the soils moisture content between direct observations and global climate models (GCM). Also, areas that are intensely farmed and irrigated cannot be associated with large-scale atmospheric conditions and resulting soil moisture.
Therefore, human intervention and land use practices are significant factors in the greening and plant life cycles and should be included in the future global climate models.
In China, however, large scale reforestation efforts and forest management practices are not treated separately from those areas that have natural greening as they are expected to experience the same transpiration and large-scale precipitation patterns as those areas included in the study.
The important thing to remember here is that climate change can shift the lifecycle of plants and all living organisms. Changes like early greening can lead to soil dryness which results in adverse climate conditions like heatwaves and droughts and reduced vegetation activity which hinders food production in the areas affected.
To access the entire study please refer to the citation below:
X.Lian, S.Piao, L.Z. X.Li, Y.Li, C.Huntingford, P.Ciais, A.Cescatti, I.A. Janssens, J.Peñuelas, W.Buermann, A.Chen, X.Li, R.B. Myneni, X.Wang, Y.Wang, Y.Yang, Z.Zeng, Y.Zhang, T.R. McVicar, Summer soil drying exacerbated by earlier spring greening of northern vegetation. Sci. Adv.6, eaax0255 (2020). Retrieved from https://advances.sciencemag.org/content/6/1/eaax0255