Comparison of the Health Benefits of Different Types of Nature

Abstract

In their study, Astell-Burt and Feng 1 address 2 important limitations of much of the research on contact with nearby nature and human health and well-being. 2 The first one is its cross-sectional design, preventing the ability to draw firm conclusions regarding the causality of observed associations. The second one is that most studies do not distinguish between different types of green and/or blue space and consequently tell us little about which type of nature is most beneficial. In their study, they begin to address this gap by making efficient use of longitudinal health data already collected for other purposes and enriching these data with land-use data on the availability of green and blue space in the residential environment. Consequently, in addition to prevalence data, incidence data were available on high risk of psychological distress, physician-diagnosed anxiety and/or depression, and less than good self-rated health. Furthermore, they distinguished 3 types of vegetation: tree canopy, grass, and low-lying vegetation. They concluded that tree canopy may be more beneficial than the other 2 types.The study by Astell-Burt and Feng 1 is definitely a step in the right direction. At the same time, it bears the markings of a journey in uncharted territory. As with many studies on this topic and despite distinguishing different types of green space, the problematization of how to best characterize access to green space is limited. For example, with regard to the presence of nature translating to actual exposure in terms of contact with or use of the green space, its distance to one's home is of great importance. A buffer size of 1.6 km seems rather large because most people will consider this distance too far to walk to and will therefore have a low probability of frequently coming in contact with the green space located in the more distant part of the buffer. Egorov et al 3 concluded that the positive effects of vegetation (on allostatic load) already decrease gradually with distance from the residence within a 500-m radius. Therefore, a smaller buffer size might have resulted in a stronger association with mental health.Furthermore, the study's information on which green spaces are included is limited. It remains unclear whether vegetation in agricultural areas within the 1.6-km buffer is included. Agricultural grasslands may not be as accessible to the general public as other types of grasslands (eg, in parks) or as wooded areas (eg, parks, forests). In addition, the spatial resolution of the land-use data used to determine the amount of different types of green space is not mentioned. This omission makes it unclear whether the sometimes isolated street trees that the authors refer to as important were actually included in the tree cover percentage. Even if they were, street trees may have constituted only a small part of the tree cover within the buffer. In their discussion, the authors mention that the level of biodiversity of the green space may be important based on a study conducted in 2007.However...

A Scoping Review of the Health Benefits of Nature-Based Physical Activity

“…Typically, these spaces have been defined as areas with predominant vegetative and/or geological features that reflect natural processes (e.g., trees, prairies, grasses) (Centers for Disease Control and Prevention, 2009;Frumkin et al, 2017;Hartig et al, 2014;Lachowycz & Jones, 2013;Taylor & Hochuli, 2017;World Health Organization, 2016). However, while much emphasis is placed on vegetation and greenness, this definition and the concept of restorative nature suggest that other types of natural environments such as water and desert environments may also provide benefits (De Vries, 2019;Kaplan & Kaplan, 1989;Kelly, 2018).…”