Untitled

Edwards, Nelson T.; Norby, R. J.

doi:10.1023/a:1004319109772

Cited by 92 publications

(6 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The effects of elevated CO2 and elevated temperature were more or less additive and no significant interaction was found in our study or in previous studies (e.g. Edwards and Norby 1999;Lin et al 2001;Dieleman et al 2012). Responses of plant productivity under the combined treatment have resembled more those in the elevated CO2-only treatment than those in the warming only treatment (Dieleman et al 2012).…”

Section: Effects Of Elevated Co2 and Temperaturesupporting

confidence: 52%

Soil CO2 efflux in boreal pine forests in the current climate and under CO2 enrichment and air warming

Niinistö¹

2015

Diss. For.

View full text Add to dashboard Cite

The aims of the study were to identify factors related to temporal and spatial variation in forest soil CO2 efflux (Fs), compare measurement chambers, and to test effects of a climate change experiment. The study was based on four-year measurements in upland Scots pine forests. Momentary plot averages of Fs ranged from 0.04 to 1.12 gCO2m −2 h −1 and annual estimates for the forested area from1750 to 2050 gCO2m −2. Soil temperature was a dominant predictor of the temporal variation in Fs (R 2 =76-82%). A temperature and degree days model predicted Fs of independent data within 15% on the average but underestimated it during the peak efflux period (July-August), possibly because of seasonal pattern in growth of roots and mycorrhiza. A comparison sub-study indicated that the reliability of the measurement chambers was not related to the principle i.e. non-steady-state through-flow, non-steady-state non-through-flow or steady-state through-flow. Spatial variability of Fs within 400 m 2 plots in four stands was large; coefficients of variation (CV) ranged from 0.10 to 0.80, with growing season averages of 0.22-0.36. A positive spatial autocorrelation was found at short distances (3-8 m). In data from several stands, thickness of the humus layer explained 28% of the variation in Fs, and with the distance to the closest trees it explained 40%. Fs also correlated with root mass of the humus layer. Between-plot differences in Fs were small. In the climate change experiment, CO2 enrichment and air warming consistently, but not always significantly, increased Fs in whole-tree chambers. Their combined effect was additive, with no interaction; i.e. +23-37% (elevated CO2), +27-43% (elevated temperature), and +35-59% (combined treatment), depending on year. Air warming was a significant factor in the 4-year data according to ANOVA. Temperature sensitivity of Fs under the warming, however, decreased in the second year.

show abstract

Section: Effects Of Elevated Co2 and Temperaturesupporting

confidence: 52%

Soil CO2 efflux in boreal pine forests in the current climate and under CO2 enrichment and air warming

Niinistö¹

2015

Diss. For.

View full text Add to dashboard Cite

show abstract

“…On the other hand, measurements made during the 2006 growing season, as well as data presented by Wan et al (2007), indicate increased soil respiration under elevated CO 2 that could reflect increased decomposition of existing soil organic matter. Studies in other grasslands indicate that elevated CO 2 can increase organic matter decomposition by altering both microbial biomass and enzyme activity (Drissner et al 2007). …”

Section: Discussionmentioning

confidence: 99%

“…Even though soil carbon dynamics under elevated CO 2 may not be representative of current-day conditions because of CO 2 induced changes in soil microbial activity (Cardon et al 2001;Drissner et al 2007), soil respiration (Heath et al 2005;Wan et al 2007), nitrogen availability (De Graaff et al 2007), and other CO 2 -specific soil processes (Niklaus and Falloon 2006), measurements of soil carbon and nitrogen under elevated CO 2 are relevant to soil carbon dynamics in an expected, future, CO 2 -rich world. The temperature treatment had no effect on accrual of new soil carbon under elevated CO 2 , but the turnover time of old soil carbon in POM was prolonged under reduced soil moisture.…”

Section: Discussionmentioning

confidence: 99%

Soil moisture surpasses elevated CO2 and temperature as a control on soil carbon dynamics in a multi-factor climate change experiment

2008

Self Cite

View full text Add to dashboard Cite

Some single-factor experiments suggest that elevated CO 2 concentrations can increase soil carbon, but few experiments have examined the effects of interacting environmental factors on soil carbon dynamics. We undertook studies of soil carbon and nitrogen in a multi-factor (CO 2 × temperature × soil moisture) climate change experiment on a constructed old-field ecosystem. After four growing seasons, elevated CO 2 had no measurable effect on carbon and nitrogen concentrations in whole soil, particulate organic matter (POM), and mineralassociated organic matter (MOM). Analysis of stable carbon isotopes, under elevated CO 2 , indicated between 14 and 19% new soil carbon under two different watering treatments with as much as 48% new carbon in POM. Despite significant belowground inputs of new organic matter, soil carbon concentrations and stocks in POM declined over four years under soil moisture conditions that corresponded to prevailing precipitation inputs (1,300 mm yr −1 ). Changes over time in soil carbon and nitrogen under a drought treatment (approximately 20% lower soil water content) were not statistically significant. Reduced soil moisture lowered soil CO 2 efflux and slowed soil carbon cycling in the POM pool. In this experiment, soil moisture (produced by different watering treatments) was more important than elevated CO 2 and temperature as a control on soil carbon dynamics.

show abstract

“…However, there were no detectable differences in root function, as none of the sampled variables were able to explain the variation in soil respiration rates around the sugar maple seedlings. Other research has demonstrated the difficulties in predicting soil respiration responses in the complex eastern deciduous forest (Edwards and Norby, 1999).…”

Section: Discussionmentioning

confidence: 99%

The Influence of Different Ground Cover Treatments on the Growth and Survival of Tree Seedlings on Remined Sites in Eastern Tennessee

Rizza¹,

Franklin²,

Buckley³

2007

JASMR

View full text Add to dashboard Cite

Abstract:There is growing interest in the reforestation of surface mined lands for various land uses including forest products and wildlife habitat. These objectives can be met by planting native tree species and seeding a ground cover to control erosion. However, many ground covers compete aggressively with tree seedlings in this region, preventing establishment. A research project was designed with two main objectives; to investigate the competitive effects of different ground cover species on the growth and survival of tree seedlings, and to identify the relationship between the growth and function of tree seedlings and microsite variables. Five tree species, native to the eastern hardwood forest surrounding the mine site, were planted in 2005: yellow poplar (Liriodendron tulipifera L.), sugar maple (Acer saccharum Marsh.), northern red oak (Quercus rubra L.), eastern redbud (Cercis canadensis L.), and Virginia pine (Pinus virginiana Mill.). Five different ground cover treatments were applied to the planted area. Two mixes consisted of native warm season grasses (NWSG), two standard reclamation mixes, and one control. Growth and survival, seedling transpiration, soil respiration, and groundcover biomass were analyzed.At each seedling, light measurements and percent herbaceous cover based on the Braun-Blanquet scale were collected. Seedling survival was related to size at planting, and to the density of ground cover. Survival was highest in moderate amounts of cover, although root collar diameter growth decreased with increasing cover in redbud and pine. Tree seedling growth and survival tended to be greatest in the native warm season grass treatments. Additional

show abstract

Untitled

Cited by 92 publications

References 23 publications

Soil CO2 efflux in boreal pine forests in the current climate and under CO2 enrichment and air warming

Soil CO2 efflux in boreal pine forests in the current climate and under CO2 enrichment and air warming

Soil moisture surpasses elevated CO2 and temperature as a control on soil carbon dynamics in a multi-factor climate change experiment

The Influence of Different Ground Cover Treatments on the Growth and Survival of Tree Seedlings on Remined Sites in Eastern Tennessee

Contact Info

Product

Resources

About