41 research outputs found
Repeated-measures ANOVA for the temperature and time effects on R<sub>h</sub> under different soil moisture treatments.
a<p>%WHC: percent of water holding capacity.</p
Regression equations of heterotrophic respiration (R<sub>h</sub>) with temperature under different moisture treatments.
a<p>%WHC: percent of water holding capacity.</p>b<p>R<sub>h</sub> represents soil heterotrophic respiration rate and T represents temperature.</p>c<p>R<sup>2</sup> is the coefficient of determination; * and ** indicate significance at P≤0.05 and P≤0.01, respectively.</p
Changes of Q<sub>10</sub> and R<sub>h</sub> with incubation time at different soil moisture treatments.
<p>The Q<sub>10</sub> regression functions are quadratic for 20%, 40% and 60% WHC and cubic for 80% and 100% WHC. Error bars (n = 4) represent standard deviations. R<sup>2</sup> is the coefficient of determination. P is the significance level.</p
Responses of soil heterotrophic respiration (R<sub>h</sub>) to changes in soil temperature after 7 (A), 30 (B), and 90 (C) days of incubation.
<p>Each data point is the mean of four replicates under each soil moisture treatment. Error bars represent standard errors (n = 4).</p
Correlations between Q<sub>10</sub> and soil microbial and chemical properties.
<p>MBC: microbial biomass carbon, DOC: dissolved organic carbon, TP: total phosphorus, and F:B: ratio of fungi to bacteria. r is the correlation coefficient. P is the significance level.</p
Wettability of Supercritical CO<sub>2</sub>–Brine–Mineral: The Effects of Ion Type and Salinity
Deep
saline aquifers are considered as perfect storage sites to sequestrate
CO<sub>2</sub>. Interfacial tensions (IFTs) and contact angles (CAs)
are key parameters in the heat and mass transfer processes for CO<sub>2</sub>/brine/mineral systems in porous media. In the present study,
a molecular dynamics simulation method was used to investigate the
effects of brine salinity and ion type on wettability of CO<sub>2</sub>/brine/mineral systems at 20 MPa and 318.15 K. Four common brines
were selected as NaCl, KCl, CaCl<sub>2</sub>, and MgCl<sub>2</sub>. Interfacial tensions, water contact angles, and hydrogen bond structure
and dynamics have been analyzed. The effects of brine salinity and
ion type on water contact angles were found to be very complicated.
For MgCl<sub>2</sub> and NaCl solutions, the contact angle increases
with salinity. For CaCl<sub>2</sub> and KCl solutions, contact angle
first increases and then remains constant with salinity. The product
of IFTÂ(CO<sub>2</sub>–brine) and the cosine of CA was found
to be constant for all brine solutions studied. In the context of
large uncertainty of experimentally measured contact angles, this
finding is very useful to predict contact angles using interfacial
tension data. Due to the fact that IFTÂ(CO<sub>2</sub>–brine)
× cosÂ(CA) is usually related with capillary pressure and residual
trapping capacity, this finding is also very helpful to predict these
parameters at different brine conditions. More work is required to
study the effects of pressure, temperature, and solid surface structure
on this relationship
Relationships between scaling constant/intercept and tree age (a), diameter at breast height (DBH, b), height (c), density (d), latitude (e), longitude (f), and elevation (g).
<p>The model with the best fit among the linear, quadratic and power function models is presented. ** significant at α = 0.01 level. Error bars are standard errors of the scaling exponents.</p
Relationships between belowground biomass and tree age (a), diameter at breast height (DBH, b), height (c), density (d), latitude (e), longitude (f), and elevation (g).
<p>The model with the best fit among the linear, quadratic and power function models is presented. ** significant at α = 0.01 level. Error bars are too small to be shown.</p
Relationships between scaling exponent and tree age (a), diameter at breast height (DBH, b), height (c), density (d), latitude (e), longitude (f), and elevation (g).
<p>The scaling exponent of each age, DBH, height, density, latitude, longitude, and elevated group was estimated using reduce major axis (RMA) regression analysis. The model with the best fit among the linear, quadratic and power function models is presented. ** significant at α = 0.01 level. Error bars are standard errors of the slopes.</p
Relationship between belowground biomass and aboveground biomass of forests in China.
<p>The model is estimated using reduced major axis regression method (n = 6153). ** significant at α = 0.01 level.</p