首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
Mangrove ecosystems play an important, but understudied, role in the cycling of carbon in tropical and subtropical coastal ocean environments. In the present study, we examined the diel dynamics of seawater carbon dioxide (CO2) and dissolved oxygen (DO) for a mangrove-dominated marine ecosystem (Mangrove Bay) and an adjacent intracoastal waterway (Ferry Reach) on the island of Bermuda. Spatial and temporal trends in seawater carbonate chemistry and associated variables were assessed from direct measurements of dissolved inorganic carbon, total alkalinity, dissolved oxygen (DO), temperature, and salinity. Diel pCO2 variability was interpolated across hourly wind speed measurements to determine variability in daily CO2 fluxes for the month of October 2007 in Bermuda. From these observations, we estimated rates of net sea to air CO2 exchange for these two coastal ecosystems at 59.8 ± 17.3 in Mangrove Bay and 5.5 ± 1.3 mmol m−2 d−1 in Ferry Reach. These results highlight the potential for large differences in carbonate system functioning and sea-air CO2 flux in adjacent coastal environments. In addition, observation of large diel variability in CO2 system parameters (e.g., mean pCO2: 390–2,841 μatm; mean pHT: 8.05–7.34) underscores the need for careful consideration of diel cycles in long-term sampling regimes and flux estimates.  相似文献   

2.
Repeated surveys of the Kennebec estuary, a macrotidal river estuary in Maine, USA, between 2004 and 2008 found spatial and temporal variability both in sources of carbon dioxide (CO2) to the estuary and the air–sea flux of estuary CO2. On an annual basis, the surveyed area of the Kennebec estuary had an area-weighted average partial pressure of CO2 (pCO2) of 559 μatm. The area-weighted average CO2 flux to the atmosphere was 3.54 mol C m?2 year?1. Overall, the Kennebec estuary was an annual source of 7.2?×?107 mol CO2 to the atmosphere. Distinct seasonality in estuarine pCO2 was observed, with shifts in the seasonal pattern evident between lower and higher salinities. Fluxes of CO2 from the estuary were elevated following two summertime storms, and inputs of riverine CO2 outweighed internal estuarine CO2 inputs in nearly all months. River and estuarine inputs of CO2 represented 68 and 32 % of the total CO2 contributions to the estuary, respectively. This study examines the variability of CO2 in a large New England estuary, and highlights the comparatively high contribution of CO2 from riverine sources.  相似文献   

3.
Air–water gas exchange is an important process in aquatic systems, including tidal rivers and estuaries. While there are now reliable and routine methods for determining gas exchange over a range of temporal and spatial scales in the ocean and these measurements have resulted in widely used wind speed parameterizations to calculate air–sea gas exchange, the same has not been true for coastal inland waterways. Some studies have suggested that this difference is methodological, while others point to the existence of additional drivers for gas exchange besides wind in rivers and estuaries. Here, we present gas transfer velocities measured in the tidal Hudson River with a method widely used in oceanic studies, the 3He/SF6 dual tracer technique. Airside and waterside forcings were determined with an anemometer and an acoustic Doppler current profiler, respectively. The results confirm that wind is the dominant driver of gas exchange in the tidal Hudson River, with negligible contribution from bottom-generated turbulence. Furthermore, a parameterization between wind speed and gas exchange developed for the ocean is able to predict gas exchange in this environment with high accuracy. It is hoped that by transferring methodology used in oceanic studies to rivers and estuaries, robust data can be obtained that will eventually allow development of widely applicable relationships between easily measured environmental variables and gas exchange in tidal inland waters.  相似文献   

4.
A field facility located in Bozeman, Montana provides the opportunity to test methods to detect, locate, and quantify potential CO2 leakage from geologic storage sites. From 9 July to 7 August 2008, 0.3 t CO2 day−1 were injected from a 100-m long, ~2.5-m deep horizontal well. Repeated measurements of soil CO2 fluxes on a grid characterized the spatio-temporal evolution of the surface leakage signal and quantified the surface leakage rate. Infrared CO2 concentration sensors installed in the soil at 30 cm depth at 0–10 m from the well and at 4 cm above the ground at 0 and 5 m from the well recorded surface breakthrough of CO2 leakage and migration of CO2 leakage through the soil. Temporal variations in CO2 concentrations were correlated with atmospheric and soil temperature, wind speed, atmospheric pressure, rainfall, and CO2 injection rate.  相似文献   

5.
Reported herein are the results of eight soil CO2 efflux surveys performed from 2006 to 2011 at Timanfaya Volcanic Field (TVF), Lanzarote Island with the aim of evaluating the long- and short-term temporal variations of the diffuse CO2 emission. Soil CO2 efflux values ranged from non-detectable up to 34.2 g m−2 d−1, with the highest values measured in September 2008. Conditional sequential Gaussian simulations (sGs) were applied to construct soil CO2 efflux distribution maps and to estimate the total CO2 output from the studied area at the TVF. Soil CO2 efflux maps showed a high spatial and temporal variability. Total CO2 emission rates ranged between 41 and 518 t d−1, February 2011 (winter) being the season when maximum diffuse CO2 emission rates were observed. To investigate the influence of external variables on the soil CO2 efflux, a geochemical station (LZT01) was installed at TVF to measure continuously the soil CO2 efflux between July 2010 and March 2012 Since external factors such as barometric pressure, rainfall, soil water content, soil and air temperatures, and wind speed influence strongly the observed soil CO2 effluxes, multiple regression analysis was applied to the time series recorded by the automatic geochemical station LZT01 to remove the contribution of these external factors. The influence of meteorological variables on soil CO2 efflux oscillations accounts for 13% of total variance, with barometric pressure, rainfall and/or soil water content having the most influence in the control of the soil CO2 efflux. These observations along with the results from the eight soil gas surveys performed at TVF indicate that the short and long-term trends in the diffuse CO2 degassing are mainly controlled by environmental factors.  相似文献   

6.
Simulation of carbon dioxide (CO2) at hourly/weekly intervals and fine vertical resolution at the continental or coastal sites is challenging because of coarse horizontal resolution of global transport models. Here the regional Weather Research and Forecasting (WRF) model coupled with atmospheric chemistry is adopted for simulating atmospheric CO2 (hereinafter WRF-CO2) in nonreactive chemical tracer mode. Model results at horizontal resolution of 27 × 27 km and 31 vertical levels are compared with hourly CO2 measurements from Tsukuba, Japan (36.05°N, 140.13 oE) at tower heights of 25 and 200 m for the entire year 2002. Using the wind rose analysis, we find that the fossil fuel emission signal from the megacity Tokyo dominates the diurnal, synoptic and seasonal variations observed at Tsukuba. Contribution of terrestrial biosphere fluxes is of secondary importance for CO2 concentration variability. The phase of synoptic scale variability in CO2 at both heights are remarkably well simulated the observed data (correlation coefficient >0.70) for the entire year. The simulations of monthly mean diurnal cycles are in better agreement with the measurements at lower height compared to that at the upper height. The modelled vertical CO2 gradients are generally greater than the observed vertical gradient. Sensitivity studies show that the simulation of observed vertical gradient can be improved by increasing the number of vertical levels from 31 in the model WRF to 37 (4 below 200 m) and using the Mellor–Yamada–Janjic planetary boundary scheme. These results have large implications for improving transport model simulation of CO2 over the continental sites.  相似文献   

7.
An increase in carbon dioxide (CO2) concentrations in the atmosphere due to anthropogenic activities is responsible for global warming and hence in recent years, CO2 measurement network has expanded globally. In the monsoon season (July–September) of year 2011, we carried out measurements of CO2 and water vapour (H2O) concentrations along with wind and air temperature over a tropical site in south-east India having rural topography. To collect these observations, the instrumentations used were the sonic anemometer for wind and temperature, and the open path H2O/CO2 infrared gas analyzer for CO2 and H2O concentrations. Using these observations, we explored the diurnal variability of CO2 flux along with sensible and latent heat. The CO2 flux was positive during night-time and negative during daytime and in phase with convective instability. The CO2 flux relationships with the meteorological parameters such as wind speed, temperature and heat fluxes have been analysed. The seasonal (monsoon) half hour mean of CO2 flux which was ?3.55 μmol m???2 s???1 indicated the experimental site as a CO2 sink region (net seasonal uptake). An increase in CO2 concentrations during weekends was not observed due to unavailability of heavy vehicular traffic.  相似文献   

8.
Oxygen air-water gas exchange was measured using floating chambers in two shallow tidal estuaries of differing bathymetry and local terrain, near Waquoit Bay, Massachusetts (United States). The specific chamber design permitted measurements of gas flux in 15 min, allowing analysis of the relationship with wind speed and tidal stage. Exchange coefficients ranged from 0.5 to 2.5 g O2·m?2 h?1 atm?1 (equivalent to piston velocities of 1.5 to 7 cm h?1) for wind speeds of 0.3 to 9 m s?1 at 10 m elevation. While the relationships for each estuary appear linear (significant linear regressions with wind speed were shown for each estuary, and the slopes were different at the 99.5% confidence level), the range of speeds differed at the two sites and an exponential function of wind speed was consistent with the combined data from both estuaries. A power function of wind speed was not an acceptable model. The exchange coefficients for our estuaries are from 57% to as low as 9% of that predicted by previously published generic equations. Because the atmospheric correction can be significant in shallow, metabolically active coastal waters, we suggest that empirically determined relationships for gas exchange versus wind for a specific estuary are preferable to the predictions of the general equations. While the floating chamber method should be used cautiously, at low winds speeds (below 8 m s?1) and in slowly flowing waters, it provides a convenient approach for quantifying these site-specific differences. The differences, especially those between shallow sheltered systems and the open waters best fit by some published relationships, are ecologically important and do not appear yet to be measurable by other methods.  相似文献   

9.
Incidents of hazardous accumulations of CO2 in homes built on or near reclaimed mine land, in the last decade, have been shown to be linked to neutralization reactions between acidic mine drainage and carbonate material. Recent research has shown that CO2 fluxes on reclaimed mine land with this hazard are, sometimes, spatially autocorrelated (i.e., the spatial variability is not random). This result implies geostatistics can be used to delineate hazardous areas where fluxes are likely to exceed established thresholds. This study applies sequential Gaussian simulation to delineate this emerging hazard on a site in southwestern Indiana, USA. Due to lack of regulatory threshold limits for CO2 flux at the current time, the authors conduct a sensitivity analysis of the threshold limit using the 75th, 90th and 95th percentiles of the measured fluxes for the first day of monitoring. These limits are used to produce hazard maps, which are validated with the known hazard at the site. This work further shows the potential of surface CO2 flux monitoring as a cheap and effective strategy to monitor and delineate such hazards to avoid residential and commercial real estate development in high risk zones.  相似文献   

10.
The vertical structure of the water column and the spatial distribution and semidiurnal variability of bacteria were investigated at six stations in the upper St. Lawrence estuary. The σ1 profiles indicate that the upper St. Lawrence is a partially mixed estuary. Stratification results from buoyancy input from the freshwater outflow of the St. Lawrence River, and its variability is controlled by tidal and, to a lesser extent, wind mixing. Calculations show that tidal mixing largely exceeds mixing caused by wind. Free and attached bacteria presented different patterns of spatial distribution and temporal variability. Free bacteria exhibited highest mean concentrations at the freshwater station (3.5–4.4 106ml?1) and lowest concentrations at the downstream stations (0.3–0.5 106ml?1); their numbers declined exponentially relative to salinity. Attached bacteria had highest mean concentrations (3.2–5.5 106ml?1) at salinities between 0.5 and 5 and were virtually absent at downseam stations (<0.05 106ml?1). The importance of semidiurnal variability was demonstrated Over the idal cycle, variability of attached bacteria was always greater than that of free bacteria. The analysis of causal models between salinity and free and attached bacteria, showed that the two types of bacteria are uncoupled and that both types have a strong relationship with salimity. Physical processes are thus important controlling factors of the distribution and variability of bacteria. Results suggest that large-scale processes, such as freshwater outflow and residual circulation, largely control free bacteria, whereas short-term and more local processes (e.g., sediment resuspension caused by wind) may also be important in the control of attached bacteria.  相似文献   

11.
During the formation and development of glacial meltwater runoff, hydrochemical erosion is abundant, especially the hydrolysis of K/Na feldspar and carbonates, which can consume H+ in the water, promote the formation of bicarbonate by dissolving atmospheric CO2, and affect the regional carbon cycle. From July 21, 2015, to July 18, 2017, the CO2 concentration and flux were observed by the eddy covariance (EC) method in the relatively flat and open moraine cover area of Koxkar Glacier in western Mt. Tianshan, China. We found that: (1) atmospheric CO2 fluxes ranged from ??408.95 to 81.58 mmol m?2 day?1 (average ? 58.68 mmol m?2 day?1), suggesting that the study area is a significant carbon sink, (2) the CO2 flux footprint contribution areas were primarily within 150 m of the EC station, averaging total contribution rates of 93.30%, 91.39%, and 90.17% of the CO2 flux in the snow accumulation, snow melting, and glacial melting periods, respectively. Therefore, the contribution areas with significant influences on CO2 flux observed at EC stations were concentrated, demonstrating that grassland CO2 flux around the glaciers had little effect at the EC stations, (3) in the predominant wind direction, under stable daytime atmospheric stratification, the measurement of CO2 flux, as interpreted by the Agroscope Reckenholz Tanikon footprint tool, was 79.09% ± 1.84% in the contribution area. This was slightly more than seen at night, but significantly lower than the average under unstable atmospheric stratification across the three periods of interest (89%). The average distance of the farthest point of the flux footprint under steady state atmospheric conditions was 202.61?±?69.33 m, markedly greater than that under non-steady state conditions (68.55?±?10.34 m). This also indicates that the CO2 flux observed using EC was affected primarily by hydrochemical erosion reactions in the glacier area, (4) a good negative correlation was found between net glacier exchange (NGE) of CO2 and air temperature on precipitation-free days. Strong ice and snow ablation could promote hydrochemical reactions of soluble substances in the debris area and accelerated sinking of atmospheric CO2. Precipitation events might reduce snow and ice melting, driven by reduced regional temperatures. However, a connection between NGE and precipitation, when less than 8.8 mm per day, was not obvious. When precipitation was greater than 8.8 mm per day, NGE decreased with increasing precipitation, (5) graphically, the slope of NGE, related to daily runoff, followed a trend: snow melting period?>?snow accumulation period?>?early glacial ablation period?>?late glacier ablation period?>?dramatic glacier ablation period. The slope was relatively large during snow melting, likely because of CO2 sinking caused by water–rock interactions. The chemical reaction during elution in the snow layer might also promote atmospheric CO2 drawdown. At the same time, the damping effect of snow cover and the almost-closed glacier hydrographic channel inhibited the formation of regional runoff, possibly providing sufficient time for the chemical reaction, thus promoting further CO2 drawdown.  相似文献   

12.
The measurement of metabolism using diel free-water oxygen techniques requires the estimation of atmospheric oxygen exchanges. We measured such exchange on nine different occasions in the freshwater, tidally-influenced Hudson River estuary using a floating dome technique. We also analyzed previously published data on the exchange of a variety of gases measured in lakes, estuaries, and open ocean waters using a wide variety of techniques. Data were expressed as a “transfer velocity” and normalized to an exchange of oxygen at 20°C. Considered together, these data indicate a significant predictive relationship when the natural log of transfer velocity is regressed with measured wind speed (r2 = 0.55; p = 0.0001). The influence of wind was particularly pronounced in estuaries and in lakes. Data from open-ocean waters showed much less influence of wind, probably because surface turbulence in these deeper waters can be temporally and spatially decoupled from wind. Our Hudson data agreed well with data collected in other systems. In general, data from estuaries—including the Hudson—indicated slightly higher transfer velocities at any given wind speed than do data from lakes (although this difference was less pronounced for our Hudson data than for other estuaries). The difference may result from some interaction of wind and tidal currents, or it may reflect a bias in the dome method of measurements; all of the estuarine data were collected using the dome approach, while the majority of the lake data were determined using an added tracer. If the dome method actually gives a biased, high estimate of oxygen flux, this is in contradiction to previous criticisms of this method that domes may underestimate fluxes by blocking wind at the water surface. We have used the regression of the natural log of transfer velocity versus wind speed developed here to estimate respiration in the Hudson estuary from diel changes in dissolved oxygen. To allow for possible biases in technique and for measurement error, we estimated 95% confidence limits around the regression. Estimates of respiration in the Hudson determined using the upper and lower 95% confidence limits are 30% higher and 12% lower than that determined when using the best-fit regression. An independently-constrained carbon budget for the tidally-influenced, freshwater Hudson River estuary indicates that respiration rates cannot be much higher than our mean estimate as calculated using the linear regression of the gas transfer and wind data to correct for air-water oxygen exchange. Gas transfer in natural systems is difficult to measure and is controlled by many interrelated physical factors. In the absence of extensive, system-specific field studies, the regression presented here should be useful in estimating atmospheric oxygen exchange in other estuarine or riverine ecosystems which are relatively deep and wide.  相似文献   

13.
Fluid inclusions have recorded the history of degassing in basalt. Some fluid inclusions in olivine and pyroxene phenocrysts of basalt were analyzed by micro-thermometry and Raman spectroscopy in this paper. The experimental results showed that many inclusions are present almost in a pure CO2 system. The densities of some CO2 inclusions were computed in terms of Raman spectroscopic characteristics of CO2 Fermi resonance at room temperature. Their densities change over a wide range, but mainly between 0.044 g/cm3 and 0.289 g/cm3. Their micro-thermometric measurements showed that the CO2 inclusions examined reached homogenization between 1145.5℃ and 1265℃ . The mean value of homogenization temperatures of CO2 inclusions in basalts is near 1210℃. The trap pressures (depths) of inclusions were computed with the equation of state and computer program. Distribution of the trap depths makes it know that the degassing of magma can happen over a wide pressure (depth) range, but mainly at the depth of 0.48 km to 3.85 km. This implicates that basalt magma experienced intensive degassing and the CO2 gas reservoir from the basalt magma also may be formed in this range of depths. The results of this study showed that the depth of basalt magma degassing can be forecasted from CO2 fluid inclusions, and it is meaningful for understanding the process of magma degassing and constraining the inorganogenic CO2 gas reservoir.  相似文献   

14.
Cave air CO2 is a vital part of the cave environment. Most studies about cave air CO2 variations are performed in caves with no streams; there are few studies to date regarding the relationship of cave air CO2 variations and drip water hydrochemistry in underground stream–developed caves. To study the relationship of underground stream, drip water, and cave air CO2, monthly and daily monitoring of air CO2 and of underground stream and drip water was performed in Xueyu Cave from 2012 to 2013. The results revealed that there was marked seasonal variation of air CO2 and stream hydrochemistry in the cave. Daily variations of cave air CO2, and of stream and drip water hydrochemistry, were notable during continuous monitoring. A dilution effect was observed by analyzing hydrochemical variations in underground stream and drip water after rainfall. High cave air CO2 along with low pH and low δ13CDIC in stream and drip water indicated that air CO2 was one of the dominant factors controlling stream and drip water hydrochemistry on a daily scale. On a seasonal scale, stream flows may promote increased cave air CO2 in summer; in turn, the higher cave air CO2 could inhibit degassing of drip water and make calcite δ13C more negative. Variation of calcite δ13C (precipitated from drip water) was in reverse of monthly temperature, soil CO2, and cave air CO2. Therefore, calcite δ13C in Xueyu Cave could be used to determine monthly changes outside the cave. However, considering the different precipitation rate of sediment in different seasons, it was difficult to use stalagmites to reconstruct environmental change on a seasonal scale.  相似文献   

15.
Hyperspectral plant signatures can be used as a short-term, as well as long-term (100-year timescale) monitoring technique to verify that CO2 sequestration fields have not been compromised. An influx of CO2 gas into the soil can stress vegetation, which causes changes in the visible to near-infrared reflectance spectral signature of the vegetation. For 29 days, beginning on July 9, 2008, pure carbon dioxide gas was released through a 100-m long horizontal injection well, at a flow rate of 300 kg day−1. Spectral signatures were recorded almost daily from an unmown patch of plants over the injection with a “FieldSpec Pro” spectrometer by Analytical Spectral Devices, Inc. Measurements were taken both inside and outside of the CO2 leak zone to normalize observations for other environmental factors affecting the plants. Four to five days after the injection began, stress was observed in the spectral signatures of plants within 1 m of the well. After approximately 10 days, moderate to high amounts of stress were measured out to 2.5 m from the well. This spatial distribution corresponded to areas of high CO2 flux from the injection. Airborne hyperspectral imagery, acquired by Resonon, Inc. of Bozeman, MT using their hyperspectral camera, also showed the same pattern of plant stress. Spectral signatures of the plants were also compared to the CO2 concentrations in the soil, which indicated that the lower limit of soil CO2 needed to stress vegetation is between 4 and 8% by volume.  相似文献   

16.
  相似文献   

17.
The gradient flux technique, which measures the gas transfer velocity (k), and new observational techniques that probe turbulence in the aqueous surface boundary layers were conducted over a tidal cycle in the Plum Island Sound, Massachusetts. Efforts were aimed at testing new methods in an estuarine system and to determine if turbulence created by tidal velocity can be responsible for the short-term variability ink. Measurements were made during a low wind day, at a site with tidal excursions of 2.7 m and a range in tidal velocity of nearly 1 m s−1. Estimates ofk using the gradient flux technique were made simultaneously with the Controlled Flux Technique (CFT), infrared imagery, and high-resolution turbulence measurements, which measure the surface renewal rate, turbulent scales, and the turbulent dissipation rate, respectively. All measurements were conducted from a small mobile catamaran that minimizes air- and water-side flow distortions. Infrared imagery showed considerable variability in the turbulent scales that affect air-water gas exchange. These measurements were consistent with variation in the surface renewal rate (range 0.02 to 2 s−1), the turbulent dissipation rate (range 10−7 to 10−5 W kg−1), andk (range 2.2 to 12.0 cm hr−1). During this low wind day, all variables were shown to correlate with tidal speed. Taken collectively our results indicate the promise of these methods for determining short-term variability in gas transfer and near surface turbulence in estuaries and demonstrate that turbulent transport associated with tidal velocity is a potentially important factor with respect to gas exchange in coastal systems.  相似文献   

18.
The CO2 migrated from deeper to shallower layers may change its phase state from supercritical state to gaseous state (called phase transition). This phase transition makes both viscosity and density of CO2 experience a sharp variation, which may induce the CO2 further penetration into shallow layers. This is a critical and dangerous situation for the security of CO2 geological storage. However, the assessment of caprock sealing efficiency with a fully coupled multi-physical model is still missing on this phase transition effect. This study extends our previous fully coupled multi-physical model to include this phase transition effect. The dramatic changes of CO2 viscosity and density are incorporated into the model. The impacts of temperature and pressure on caprock sealing efficiency (expressed by CO2 penetration depth) are then numerically investigated for a caprock layer at the depth of 800 m. The changes of CO2 physical properties with gas partial pressure and formation temperature in the phase transition zone are explored. It is observed that phase transition revises the linear relationship of CO2 penetration depth and time square root as well as penetration depth. The real physical properties of CO2 in the phase transition zone are critical to the safety of CO2 sequestration. Pressure and temperature have different impact mechanisms on the security of CO2 geological storage.  相似文献   

19.
Seismic surveys successfully imaged a small scale CO2 injection (1,600 ton) conducted in a brine aquifer of the Frio Formation near Houston, Texas. These time-lapse borehole seismic surveys, crosswell and vertical seismic profile (VSP), were acquired to monitor the CO2 distribution using two boreholes (the new injection well and a pre-existing well used for monitoring) which are 30 m apart at a depth of 1,500 m. The crosswell survey provided a high-resolution image of the CO2 distribution between the wells via tomographic imaging of the P-wave velocity decrease (up to 500 m/s). The simultaneously acquired S-wave tomography showed little change in S-wave velocity, as expected for fluid substitution. A rock physics model was used to estimate CO2 saturations of 10–20% from the P-wave velocity change. The VSP survey resolved a large (∼70%) change in reflection amplitude for the Frio horizon. This CO2 induced reflection amplitude change allowed estimation of the CO2 extent beyond the monitor well and on three azimuths. The VSP result is compared with numerical modeling of CO2 saturations and is seismically modeled using the velocity change estimated in the crosswell survey.  相似文献   

20.
Motivated by the rapid increase in atmospheric CO2 due to human activities since the Industrial Revolution, and the climate changes it produced, the world’s concerned scientific community has made a huge effort to investigate the global carbon cycle. However, the results reveal that the global CO2 budget cannot be balanced, unless a “missing sink” is invoked. Although numerous studies claimed to find the “missing sink”, none of those claims has been widely accepted. This current study showed that alkaline soil on land are absorbing CO2 at a rate of 0.3–3.0 μmol m−2 s−1 with an inorganic, non-biological process. The intensity of this CO2 absorption is determined by the salinity, alkalinity, temperature and water content of the saline/alkaline soils, which are widely distributed on land. Further studies revealed that high salinity or alkalinity positively affected the CO2 absorbing intensity, while high temperature and water content had a negative effect on the CO2 absorbing intensity of these soils. This inorganic, non-biological process of CO2 absorption by alkaline soils might have significant implications to the global carbon budget accounting.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号