Urban trees "live fast, die young" compared to those in rural forests

According to a study published on May 8 in the open access journal, urban trees grow faster but die faster than rural trees, resulting in a net loss of carbon storage from street trees over time. PLOS ONE by Ian Smith of Boston University, USA, and his colleagues. The results suggest that plantation initiatives alone may not be enough to maintain or improve vegetation cover and biomass because of the unique demographics of urban ecosystems.

Municipalities are adopting greening initiatives as a key strategy to improve urban sustainability and combat the environmental impacts of expansive urbanization. Many greening initiatives aim to increase urban cover through tree planting, but our understanding of the dynamics of street tree ecosystems is limited and our understanding of the structure and structure of trees is limited. Vegetation functioning based on intact and rural forests may not apply to urban ecosystems. To address this deficiency, Smith and his colleagues estimated growth, mortality and planting rates based on the size of trees under municipal control. They used a model to predict short-term changes in above-ground carbon pools of street trees under several planting and management scenarios. and compared their results to those of rural forest systems.

The researchers found accelerated rates of carbon cycling in street trees, with average diameter growth rates almost four times faster in the town of Bostonthan, in nearby forest stands, in the Massachusetts countryside. Despite the increased growth of urban trees, high mortality losses lead to a net loss of carbon storage from street trees: average mortality rates are more than double those of rural forests.

The results suggest that initiatives to assist in the establishment and maintenance of tree health are essential for increasing forest cover and for maintaining and increasing carbon storage in vegetation. According to the authors, strategic planting and maintenance combinations will maximize the sustainability of greening initiatives as an effective tool for mitigating climate change.

Smith adds: "Cities are at the forefront of implementing climate change mitigation policies, including urban greening, to combat rising temperatures and CO2 concentrations in cities. Atmosphere We find that tree planting initiatives may not be enough to maintain urban canopies in older cities like Boston, MA Due to the age and size structure of the canopy In the existing forest, it is imperative that efforts be made to assist in the establishment and maintenance of tree health in order to increase forest cover and maximize the wide range of ecosystem services provided by urban forest cover. "