Semi-rigid chambers for methane gas flux measurements on tree stems
نویسندگان
چکیده
There is increasing interest in the measurement of methane (CH4) emissions from tree stems in a wide range of ecosystems so as to determine how they contribute to the total ecosystem flux. To date, tree CH4 fluxes are commonly measured using rigid closed chambers (static or dynamic), which often pose challenges as these are bulky and limit measurement of CH4 fluxes to only a very narrow range of tree stem sizes and shapes. To overcome these challenges we aimed to design and test new semi-rigid stem-flux chambers (or sleeves). We compared the CH4 permeability of the new semi-rigid chambers with that of the traditional rigid chamber approach, in the laboratory and in the field, with continuous flow or syringe injections. We found that the semi-rigid chambers had reduced gas permeability and optimal stem gas exchange surface to total chamber volume ratio (Sc / Vtot) allowing better headspace mixing, especially when connected in a dynamic mode to a continuous flow gas analyser. Semirigid sleeves can easily be constructed and transported in multiple sizes, are extremely light, cheap to build and fast to deploy. This makes them ideal for use in remote ecosystems where access logistics is complicated.
منابع مشابه
Technical Note: Semi-rigid chambers for methane gas flux measurements on tree stems
There is increasing interest in the measurement of methane (CH4) emissions from tree stems in a wide range of ecosystems so as to determine how they contribute to the total ecosystem flux. To date, tree CH4 fluxes are commonly measured using rigid closed chambers (static or dynamic), which often pose challenges as these are bulky and limit measurement of CH4 fluxes to only a very narrow range o...
متن کاملPinus sylvestris as a missing source of nitrous oxide and methane in boreal forest
Boreal forests comprise 73% of the world's coniferous forests. Based on forest floor measurements, they have been considered a significant natural sink of methane (CH4) and a natural source of nitrous oxide (N2O), both of which are important greenhouse gases. However, the role of trees, especially conifers, in ecosystem N2O and CH4 exchange is only poorly understood. We show for the first time ...
متن کاملTechnical note: drifting versus anchored flux chambers for measuring greenhouse gas emissions from running waters
Stream networks have recently been discovered to be major but poorly constrained natural greenhouse gas (GHG) sources. A fundamental problem is that several measurement approaches have been used without crosscomparisons. Flux chambers represent a potentially powerful methodological approach if robust and reliable ways to use chambers on running water can be defined. Here we compare the use of a...
متن کاملSpatiotemporal patterns in methane flux and gas transfer velocity at low wind speeds: Implications for upscaling studies on small lakes
Lakes contribute significantly to the global natural emissions of methane (CH4) and carbon dioxide. However, to accurately incorporate them into the continental carbon balance more detailed surveys of lacustrine greenhouse gas emissions are needed, especially in respect to spatiotemporal variability and to how this affects the upscaling of results. We investigated CH4 flux from a small, wind-sh...
متن کاملQuantifying greenhouse gas flux in a restored tallgrass prairie; does chamber material matter?
Tallgrass prairie ecosystems play a vital role in the carbon cycle; their restoration may be an important component of mitigating future climate change. To quantify the biosphere-to-atmosphere exchange of greenhouse gases, enclosure based chamber systems are frequently used because they are simple and inexpensive to construct, and can be easily replicated in a variety of ecosystems. We tested f...
متن کامل