How climate and vegetation type influence evapotranspiration and water use efficiency in Canadian forest, peatland and grassland ecosystems

Brümmer, Christian; Black, T. A.; Jassal, Rachhpal S.; Grant, N.J.; Spittlehouse, David L.; Chen, Baozhang; Nesic, Zoran; Amiro, B.D.; Arain, M. Altaf; Barr, Alan G.; Bourque, Charles P.‐A.; Coursolle, Carole; Dunn, Allison L.; Flanagan, Lawrence B.; Humphreys, Elyn; Lafleur, Peter M.; Margolis, Hank A.; McCaughey, J. H.; Wofsy, Steven C.

doi:10.1016/j.agrformet.2011.04.008

Cited by 235 publications

(152 citation statements)

References 64 publications

Supporting

Mentioning

131

Contrasting

Order By: Relevance

“…Our analyses confirmed the latitudinal pattern of AET and its significant relationships with MAP, MAT and vegetation types reported in previous studies (Jung et al, 2011;Brümmer et al, 2012;Xiao et al, 2013). Given the pronounced covariation or interactive effects among climatic factors (e.g., MAT vs. R n , MAT vs, VPD, MAP vs. RH) and vegetation attributes (e.g., MAT vs. LAI, MAP vs. LAI) (Law et al, 2002), it is not surprised that the spatial patterns of AET significantly correlated with that of R n , VPD, RH and LAI.…”

Section: Effects Of Climate and Vegetation On The Spatial Variation Isupporting

confidence: 77%

“…The spatial patterns of AET have been analyzed using water flux measurements collected by EC method in China (Xiao et al, 2013) and Canada (Brümmer et al, 2012), and they concluded that the spatial patterns of AET were mainly affected by mean annual precipitation (MAP), mean annual air temperature (MAT) and vegetation type. As we know, the physical ET process is influenced by various interconnected environmental and biological factors (Jarvis and McNaughton, 1986;Wilson and Baldocchi, 2000;Wang and Dickinson, 2012).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Spatial variation in annual actual evapotranspiration of terrestrial ecosystems in China: Results from eddy covariance measurements

Zheng

Wang

et al. 2016

J. Geogr. Sci.

View full text Add to dashboard Cite

Abstract:Understanding the spatial variation in annual actual evapotranspiration (AET) and its influencing factors is crucial for a better understanding of hydrological processes and water resources management. By synthesizing ecosystem-level observations of eddy-covariance flux sites in China (a total of 61 sites), we constructed the most complete AET dataset in China up to now. Based on this dataset, we quantified the statistic characteristics of AET and water budgets (defined as the ratio of AET to annual mean precipitation (MAP), AET/MAP) of terrestrial ecosystems in China. Results showed that AET differed significantly among both different vegetation types and climate types in China, with overall mean AET of 534.7±232.8 mm yr -1 . AET/MAP also differed significantly among different climate types, but there were no distinct differences in AET/MAP values across vegetation types, with mean AET/MAP of 0.82±0.28 for non-irrigated ecosystems. We further investigated how the main climatic factors and vegetation attributes control the spatial variation in AET. Our findings revealed that the spatial variation of AET in China was closely correlated with the geographical patterns of climate and vegetation, in which the effects of total annual net radiation (R n ), MAP and mean annual air temperature (MAT) were dominant. Thus, we proposed an empirical equation to describe the spatial patterns of AET in China, which could explain about 84% of the spatial variation in AET of terrestrial ecosystems in China. Based on the constructed dataset, we also evaluated the uncertainties of five published global evapotranspiration products in simulating 1392 Journal of Geographical Sciences site-specific AET in China. Results showed that large biases in site-specific AET values existed for all five global evapotranspiration products, which indicated that it is necessary to involve more observation data of China in their parameterization or validation, while our AET dataset would provide a data source for it.

show abstract

Section: Effects Of Climate and Vegetation On The Spatial Variation Isupporting

confidence: 77%

Section: Introductionmentioning

confidence: 99%

Spatial variation in annual actual evapotranspiration of terrestrial ecosystems in China: Results from eddy covariance measurements

Zheng

Wang

et al. 2016

J. Geogr. Sci.

View full text Add to dashboard Cite

show abstract

“…Additionally, the vapor consumption process (T or ET) would closely correlate with plant photosynthesis processes (e.g., GEP and NEE) (Chen et al 2009b;Xu et al 2013). Therefore, the influence of grassland use on the ET budget should be a key factor in determining WUE for both ecosystem and canopy scales (Brümmer et al 2012). …”

Section: Difference Of Et Compositions Among Different Land Uses Of Smentioning

confidence: 99%

“…Land use change may significantly affect ecosystem WUE by changing ecosystem carbon and water budgets (Fisher et al 2008) and consequently have impact on regional and global climates. There has been limited research on land use pattern effects on grassland ecosystem WUE (Brümmer et al 2012). Therefore, understanding ecosystem WUE and its key controlling processes in response to land use change is helpful for more accurately predicting future ecosystem functions, including regional primary productivity, carbon storage, and water balance.…”

Section: Introductionmentioning

confidence: 99%

Comparison of evapotranspiration components and water-use efficiency among different land use patterns of temperate steppe in the Northern China pastoral-farming ecotone

Fan

et al. 2015

Int J Biometeorol

View full text Add to dashboard Cite

Water-use efficiency (WUE), which links carbon and water cycles, is an important indicator of assessing the interactions between ecosystems and regional climate. Using chamber methods with and without plant removal treatments, we investigated WUE and evapotranspiration (ET) components in three ecosystems with different land-use types in Northern China pastoral-farming ecotone. In comparison, ET of the ecosystems with grazing exclusion and cultivating was 6.7 and 13.4 % higher than that of the ecosystem with free grazing. The difference in ET was primarily due to the different magnitudes of soil water evaporation (E) rather than canopy transpiration (T). Canopy WUE (WUEc, i.e., the ratio of gross primary productivity to T) at the grazing excluded and cultivated sites was 17 and 36 % higher than that at the grazing site. Ecosystem WUE (WUEnep, i.e., the ratio of net ecosystem productivity to ET) at the cultivated site was 34 and 28 % lower in comparison with grazed and grazing excluded stepped, respectively. The varied leaf area index (LAI) of different land uses was correlated with microclimate and ecosystem vapor/carbon exchange. The LAI changing with land uses should be the primary regulation of grassland WUE. These findings facilitate the mechanistic understanding of carbon-water relationships at canopy and ecosystem levels and projection of the effects of land-use change on regional climate and productivity.

show abstract

“…They are, however, essential for permanent monitoring of the N r exchange between ecosystems and the atmosphere within an eddy-covariance (EC) setup. EC is the currently preferred method to measure continuously the exchange of CO 2 , water vapour and sensible heat over time scales of hours to decades, thus enabling the evaluation of seasonal and interannual variability in these exchanges and the elucidation of their climatic controls (Baldocchi et al, 2001;Coursolle et al, 2006;Brümmer et al, 2012a). In the last decade, substantial progress has been made in the use of tunable diode laser absorption spectroscopy (TDLAS) and quantum cascade lasers (QCL) as well as devices originating from individual applications such as Fourier transform infrared (FTIR) spectrometers.…”

Section: Exchange Measurements Of Reactive Nitrogen Compoundsmentioning

confidence: 99%

TRANC – a novel fast-response converter to measure total reactive atmospheric nitrogen

Marx¹,

Brümmer

Ammann

et al. 2012

Atmos. Meas. Tech.

View full text Add to dashboard Cite

Abstract. The input and loss of plant available nitrogen (reactive nitrogen: N r ) from/to the atmosphere can be an important factor for the productivity of ecosystems and thus for its carbon and greenhouse gas exchange. We present a novel converter for reactive nitrogen (TRANC: Total Reactive Atmospheric Nitrogen Converter), which offers the opportunity to quantify the sum of all airborne reactive nitrogen compounds ( N r ) in high time resolution. The basic concept of the TRANC is the full conversion of all N r to nitrogen monoxide (NO) within two reaction steps. Initially, reduced N r compounds are being oxidised, and oxidised N r compounds are thermally converted to lower oxidation states. Particulate N r is being sublimated and oxidised or reduced afterwards. In a second step, remaining higher nitrogen oxides or those generated in the first step are catalytically converted to NO with carbon monoxide used as reduction gas. The converter is combined with a fast response chemiluminescence detector (CLD) for NO analysis and its performance was tested for the most relevant gaseous and particulate N r species under both laboratory and field conditions. Recovery rates during laboratory tests for NH 3 and NO 2 were found to be 95 and 99 %, respectively, and 97 % when the two gases were combined. In-field longterm stability over an 11-month period was approved by a value of 91 % for NO 2 . Effective conversion was also found for ammonium and nitrate containing particles. The recovery rate of total ambient N r was tested against the sum of individual measurements of NH 3 , HNO 3 , HONO, NH + 4 , NO − 3 , and NO x using a combination of different well-established devices. The results show that the TRANC-CLD system precisely captures fluctuations in N r concentrations and also matches the sum of all individual N r compounds measured by the different single techniques. The TRANC features a specific design with very short distance between the sample air inlet and the place where the thermal and catalytic conversions to NO occur. This assures a short residence time of the sample air inside the instrument, and minimises wall sorption problems of water soluble compounds. The fast response time (e-folding times of 0.30 to 0.35 s were found during concentration step changes) and high accuracy in capturing the dominant N r species enables the converter to be used in an eddy covariance setup. Although a source attribution of specific N r compounds is not possible, the TRANC is a new reliable tool for permanent measurements of the net N r flux between ecosystem and atmosphere at a relatively low maintenance and reasonable cost level allowing for diurnal, seasonal and annual investigations.

show abstract

How climate and vegetation type influence evapotranspiration and water use efficiency in Canadian forest, peatland and grassland ecosystems

Cited by 235 publications

References 64 publications

Spatial variation in annual actual evapotranspiration of terrestrial ecosystems in China: Results from eddy covariance measurements

Spatial variation in annual actual evapotranspiration of terrestrial ecosystems in China: Results from eddy covariance measurements

Comparison of evapotranspiration components and water-use efficiency among different land use patterns of temperate steppe in the Northern China pastoral-farming ecotone

TRANC – a novel fast-response converter to measure total reactive atmospheric nitrogen

Contact Info

Product

Resources

About