Soil warming and trace gas fluxes: experimental design and preliminary flux results

• Published in: Oecologia 1993-02, Vol.93 (1), p.18-24
• Main Authors: Peterjohn, W.T. (Marine Biological Lab., Woods Hole (USA). Center of Ecosystems), Melillo, J.M, Bowles, F.P, Steudler, P.A
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Animal, plant and microbial ecology; Applied ecology; BIOCHIMIE; Biogeochemistry; Biological and medical sciences; BIOQUIMICA; BOSQUES; ECHANGE GAZEUX; Ecotoxicology, biological effects of pollution; EFECTO INVERNADERO; EFFET DE SERRE; Forest ecosystems; Forest soils; FORET; Fundamental and applied biological sciences. Psychology; Global change; Global warming; Hardwood forests; INTERCAMBIO DE GASES; Soil ecology; Soil heating; Soil temperature; SOL DE FORET; SUELO FORESTAL; Temperate forests; TEMPERATURA DEL SUELO; Temperature control; TEMPERATURE DU SOL; Temperature gradients; Terrestrial environment, soil, air; Thermistors
• ISSN: 0029-8549; 1432-1939
• DOI: 10.1007/bf00321185

Several experiments to determine a procedure for uniformly warming soil 5 C above ambient using a buried heating cable were conducted. These experiments produced a successful design that could: 1) maintain a temperature difference of 5 C over a wide range of environmental conditions; 2) reduce intercable temperature variability to ca 1.5 C; 3) maintain a temperature difference of 5 C near the edges of the plot; and 4) respond rapidly to changes in the environment. In addition, this design required electrical power only 42% of the time. Preliminary measurements indicate that heating increased CO2 emission by a factor of ca. 1.6 and decreased the C concentration in the O soil horizon by as much as 36%. In addition warming the soil accelerated the emergence and early growth of the wild lily of the valley (Maianthemum canadense Desf.). The relationship between CO2 flux and soil temperature derived from this soil warming experiment was consistent with data from other hardwood forests around the world. Since the other hardwood forests were warmed naturally, it appears that for soil respiration, warming the soil with buried heating cables differs little from natural, aboveground warming. By warming soil beyond the range of natural variability, a multi-site, long-term soil warming experiment may be valuable in helping us understand how ecosystems will respond to global warming.