Vertaisarvioitu alkuperäisartikkeli tai data-artikkeli tieteellisessä aikakauslehdessä (A1)
Strong influence of trees outside forest in regulating microclimate of intensively modified Afromontane landscapes
Julkaisun tekijät: Aalto Iris Johanna, Maeda Eduardo Eiji, Heiskanen Janne, Aalto Eljas Kullervo, Pellikka Petri Kauko Emil
Kustantaja: Copernicus Publications
Julkaisuvuosi: 2022
Journal: Biogeosciences
Tietokannassa oleva lehden nimi: BIOGEOSCIENCES
Lehden akronyymi: BIOGEOSCIENCES
Volyymi: 19
Julkaisunumero: 17
Aloitussivu: 4227
Lopetussivun numero: 4247
Sivujen määrä: 21
ISSN: 1726-4170
eISSN: 1726-4189
DOI: http://dx.doi.org/10.5194/bg-19-4227-2022
Verkko-osoite: https://bg.copernicus.org/articles/19/4227/2022/
Rinnakkaistallenteen osoite: https://research.utu.fi/converis/portal/detail/Publication/176554526
Climate change is expected to have detrimental consequences on fragile ecosystems, threatening biodiversity, as well as food security of millions of people. Trees are likely to play a central role in mitigating these impacts. The microclimatic conditions below tree canopies usually differ substantially from the ambient macroclimate as vegetation can buffer temperature changes and variability. Trees cool down their surroundings through several biophysical mechanisms, and the cooling benefits occur also with trees outside forest. The aim of this study was to examine the effect of canopy cover on microclimate in an intensively modified Afromontane landscape in Taita Taveta, Kenya. We studied temperatures recorded by 19 microclimate sensors under different canopy covers, as well as land surface temperature (LST) estimated by Landsat 8 thermal infrared sensor. We combined the temperature records with high-resolution airborne laser scanning data to untangle the combined effects of topography and canopy cover on microclimate. We developed four multivariate regression models to study the joint impacts of topography and canopy cover on LST. The results showed a negative linear relationship between canopy cover percentage and daytime mean (R-2 = 0.65) and maximum (R-2 = 0.75) temperatures. Any increase in canopy cover contributed to reducing temperatures. The average difference between 0 % and 100 % canopy cover sites was 5.2 degrees C in mean temperatures and 10.2 degrees C in maximum temperatures. Canopy cover (CC) reduced LST on average by 0.05 degrees C per percent CC. The influence of canopy cover on microclimate was shown to vary strongly with elevation and ambient temperatures. These results demonstrate that trees have a substantial effect on microclimate, but the effect is dependent on macroclimate, highlighting the importance of maintaining tree cover particularly in warmer conditions. Hence, we demonstrate that trees outside forests can increase climate change resilience in fragmented landscapes, having strong potential for regulating regional and local temperatures.
Ladattava julkaisu This is an electronic reprint of the original article. |  |
