An Index for Assessing Climate Change and Elevated Carbon Dioxide Effects on Loblolly Pine Productivity

1998 ◽  
pp. 367-389 ◽  
Author(s):  
David Arthur Sampson ◽  
H. Lee Allen ◽  
Philip M. Dougherty
Keyword(s):  
Climate Change ◽  
Carbon Dioxide ◽  
Loblolly Pine ◽  
Elevated Carbon Dioxide

scholarly journals AMF Inoculation Can Enhance Yield of Transgenic Bt Maize and Its Control Efficiency Against Mythimna separata Especially Under Elevated CO2

2021 ◽  
Vol 12 ◽  
Author(s):  
Long Wang ◽  
Xiaohui Wang ◽  
Fanqi Gao ◽  
Changning Lv ◽  
Likun Li ◽  
...  
Keyword(s):  
Climate Change ◽  
Gene Expression ◽  
Carbon Dioxide ◽  
Carbon Dioxide Concentration ◽  
Maize Yield ◽  
Elevated Carbon Dioxide ◽  
Mythimna Separata ◽  
Bt Toxin ◽  
Maize Leaves ◽  
Growth Development

The promotion and application of transgenic Bt crops provides an approach for the prevention and control of target lepidopteran pests and effectively relieves the environmental pressure caused by the massive usage of chemical pesticides in fields. However, studies have shown that Bt crops will face a new risk due to a decrease in exogenous toxin content under elevated carbon dioxide (CO2) concentration, thus negatively affecting the ecological sustainability of Bt crops. Arbuscular mycorrhizal fungi (AMF) are important beneficial microorganisms that can effectively improve the nutrient status of host plants and are expected to relieve the ecological risk of Bt crops under increasing CO2 due to global climate change. In this study, the Bt maize and its parental line of non-transgenic Bt maize were selected and inoculated with a species of AMF (Funneliformis caledonium, synonyms: Glomus caledonium), in order to study the secondary defensive chemicals and yield of maize, and to explore the effects of F. caledonium inoculation on the growth, development, and reproduction of the pest Mythimna separata fed on Bt maize and non-Bt maize under ambient carbon dioxide concentration (aCO2) and elevated carbon dioxide concentration (eCO2). The results showed that eCO2 increased the AM fungal colonization, maize yield, and foliar contents of jasmonic acid (JA) and salicylic acid (SA), but decreased foliar Bt toxin content and Bt gene expression in Bt maize leaves. F. caledonium inoculation increased maize yield, foliar JA, SA contents, Bt toxin contents, and Bt gene expression in Bt maize leaves, and positively improved the growth, development, reproduction, and food utilization of the M. separata fed on non-Bt maize. However, F. caledonium inoculation was unfavorable for the fitness of M. separata fed on Bt maize, and the effect was intensified when combined with eCO2. It is indicated that F. caledonium inoculation had adverse effects on the production of non-Bt maize due to the high potential risk of population occurrence of M. separata, while it was just the opposite for Bt maize. Therefore, this study confirms that the AMF can increase the yield and promote the expression levels of its endogenous (JA, SA) and exogenous (Bt toxin) secondary defense substances of Bt maize under eCO2, and finally can enhance the insect resistance capacity of Bt crops, which will help ensure the sustainable utilization and safety of Bt crops under climate change.

Evaluation of the growth response of arid zone invasive species Salvia verbenaca cultivars to atmospheric carbon dioxide and soil moisture

2020 ◽  
Vol 42 (1) ◽  
pp. 45
Author(s):  
Sandra L. Weller ◽  
Muhammad M. Javaid ◽  
Singarayer K. Florentine
Keyword(s):  
Climate Change ◽  
Carbon Dioxide ◽  
Seed Weight ◽  
Seed Mass ◽  
Field Capacity ◽  
Elevated Carbon Dioxide ◽  
Future Climate Change ◽  
Drought Conditions ◽  
100 Seed Weight ◽  
Number Of Seeds

Although climate change is expected to affect the ecology of many weed species, the nature and scale of these responses is presently not well defined. This presages a suite of potential problems for the agricultural industries. Consequently, we investigated the effects of anticipated climate change on biomass and seed production, for two varieties of wild sage, Salvia verbenaca L. var. verbenaca and Salvia verbenaca var. vernalis Bioss. For the investigation, ambient (400 ppm) and elevated (700 ppm) carbon dioxide conditions, in combination with well-watered (100% field capacity) and drought conditions (60% field capacity), were selected to represent alternative climate scenarios. The alteration in biomass production was represented by a combined measurement of nine variables; plant height, stem diameter, number of leaves, number of branches, leaf area, leaf thickness, shoot biomass, root biomass and dry leaf weight, and fecundity was measured via two variables; 100 seed weight and number of seeds per plant. All biomass measurements were reduced in a drought situation compared with well-watered conditions in ambient carbon dioxide (400 ppm), and each corresponding measurement was greater under elevated carbon dioxide (700 ppm) regardless of water treatment. In contrast, this was not observed for 100 seed weight or number of seeds per plant. Although a similar profile of a reduction in fecundity parameters was observed under drought conditions compared with well-watered conditions in ambient carbon dioxide, there was an increase in seed mass only for var. verbenaca under elevated carbon dioxide in both water treatments. In addition, there was a very small increase in the number of seeds in this species under drought conditions in elevated carbon dioxide, with neither increase in seed mass or seed number being observed in var. vernalis. These results suggest that although future climate change may result in increased competition of both these varieties with desirable plants, their management strategies will need to focus on effects of increased size of the weeds, rather than only attempting to reduce the seed bank holdings.

scholarly journals Modelling effects of acid deposition and climate change on soil and run-off chemistry at Risdalsheia, Norway

2001 ◽  
Vol 5 (3) ◽  
pp. 487-498 ◽  
Author(s):  
J. P. Mol-Dijkstra ◽  
H. Kros
Keyword(s):  
Climate Change ◽  
Carbon Dioxide ◽  
Temperature Effect ◽  
Elevated Carbon Dioxide ◽  
Nitrogen Leaching ◽  
Temporary Increase ◽  
Long Term Effects ◽  
Increased Temperature ◽  
Run Off

Abstract. Elevated carbon dioxide levels, caused by anthropogenic emissions of carbon dioxide to the atmosphere, and higher temperature may lead to increased plant growth and uptake of nitrogen, but increased temperature may lead to increased nitrogen mineralisation causing enhanced nitrogen leaching. The overall result of both counteracting effects is largely unknown. To gain insight into the long-term effects, the geochemical model SMART2 was applied using data from the catchment-scale experiments of the RAIN and CLIMEX projects, conducted on boreal forest ecosystems at Risdalsheia, southern Norway. These unique experiments at the ecosystem scale provide information on the short-term effects and interactions of nitrogen deposition and increased temperature and carbon dioxide on carbon and nitrogen cycling and especially the run-off chemistry. To predict changes in soil processes in response to climate change, the model was extended by including the temperature effect on mineralisation, nitrification, denitrification, aluminium dissolution and mineral weathering. The extended model was tested on the two manipulated catchments at Risdalsheia and long-term effects were evaluated by performing long-time runs. The effects of climate change treatment, which resulted in increased nitrogen fluxes at both catchments, were slightly overestimated by SMART2. The temperature dependency of mineralisation was simulated adequately but the temperature effect on nitrification was slightly overestimated. Monitored changes in base cation concentrations and pH were quite well simulated with SMART2. The long-term simulations indicate that the increase in nitrogen run-off is only a temporary effect; in the long-term, no effect on total nitrogen leaching is predicted. At higher deposition levels the temporary increase in nitrogen leaching lasts longer than at low deposition. Contrary to nitrogen leaching, temperature increase leads to a permanent decrease in aluminium concentrations and pH. Keywords: elevated carbon dioxide, temperature, forest ecosystem, modelling, nitrogen run-off.

Phosphorus supply affects the photosynthetic capacity of loblolly pine grown in elevated carbon dioxide

1994 ◽  
Vol 14 (11) ◽  
pp. 1229-1244 ◽  
Author(s):  
J. D. Lewis ◽  
K. L. Griffin ◽  
R. B. Thomas ◽  
B. R. Strain
Keyword(s):  
Carbon Dioxide ◽  
Loblolly Pine ◽  
Photosynthetic Capacity ◽  
Elevated Carbon Dioxide
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