Plastic debris increases circadian temperature extremes in beach sediments

JOURNAL OF HAZARDOUS MATERIALS

卷:416

Article

Lavers, Jennifer L.¹  Rivers-Auty, Jack²  Bond, Alexander L.³ 

[1] Univ Tasmania, Inst Marine & Antarctic Studies, Battery Point, Tas 7004, Australia

[2] Univ Tasmania, Tasmanian Sch Med, Hobart, Tas 7000, Australia

[3] Nat Hist Museum, Dept Life Sci, Bird Grp, Tring HP23 6AP, Herts, England

关键词: Indian Ocean;    Marine debris;    Sediment properties;    South Pacific;    Thermal gradient;   

DOI  :  10.1016/j.jhazmat.2021.126140

来源: Elsevier

【 摘 要 】

Plastic pollution is the focus of substantial scientific and public interest, leading many to believe the issue is well documented and managed, with effective mitigation in place. However, many aspects are poorly understood, including fundamental questions relating to the scope and severity of impacts (e.g., demographic consequences at the population level). Plastics accumulate in significant quantities on beaches globally, yet the consequences for these terrestrial environments are largely unknown. Using real world, in situ measurements of circadian thermal fluctuations of beach sediment on Henderson Island and Cocos (Keeling) Islands, we demonstrate that plastics increase circadian temperature extremes. Particular plastic levels were associated with increases in daily maximum temperatures of 2.45 degrees C and decreases of daily minimum by - 1.50 degrees C at 5 cm depth below the accumulated plastic. Mass of surface plastic was high on both islands (Henderson: 571 +/- 197 g/m(2); Cocos: 3164 +/- 1989 g/m(2)), but did not affect thermal conductivity, specific heat capacity, thermal diffusivity, or moisture content of beach sediments. Therefore, we suggest plastic effects sediment temperatures by altering thermal inputs and outputs (e.g., infrared radiation absorption). The resulting circadian temperature fluctuations have potentially significant implications for terrestrial ectotherms, many of which have narrow thermal tolerance limits and are functionally important in beach habitats.

【 授权许可】

Free