Seasonal changes in root and soil respiration of ozone-exposed ponderosa pine (Pinus ponderosa) grown in different substrates

Exposure to ozone (O3 ) has been shown to decrease the allocation of carbon to tree roots. Decreased allocation of carbon to roots might disrupt root metabolism and rhizosphere organisms. The effects of soil type and shoot O3 exposure on below-ground respiration and soil microbial populations were i...

Description complète

Détails bibliographiques
Publié dans:The New phytologist. - 1984. - 136(1997), 4 vom: 18. Aug., Seite 627-643
Auteur principal: Scagel, C F (Auteur)
Autres auteurs: Andersen, C P
Format: Article en ligne
Langue:English
Publié: 1997
Accès à la collection:The New phytologist
Sujets:Journal Article O3 microbial respiration ponderosa pine respiration quotient root respiration
LEADER 01000caa a22002652c 4500
001 NLM324178042
003 DE-627
005 20250301111706.0
007 cr uuu---uuuuu
008 231225s1997 xx |||||o 00| ||eng c
024 7 |a 10.1046/j.1469-8137.1997.00779.x  |2 doi 
028 5 2 |a pubmed25n1080.xml 
035 |a (DE-627)NLM324178042 
035 |a (NLM)33863111 
040 |a DE-627  |b ger  |c DE-627  |e rakwb 
041 |a eng 
100 1 |a Scagel, C F  |e verfasserin  |4 aut 
245 1 0 |a Seasonal changes in root and soil respiration of ozone-exposed ponderosa pine (Pinus ponderosa) grown in different substrates 
264 1 |c 1997 
336 |a Text  |b txt  |2 rdacontent 
337 |a ƒaComputermedien  |b c  |2 rdamedia 
338 |a ƒa Online-Ressource  |b cr  |2 rdacarrier 
500 |a Date Revised 19.04.2021 
500 |a published: Print 
500 |a Citation Status PubMed-not-MEDLINE 
520 |a Exposure to ozone (O3 ) has been shown to decrease the allocation of carbon to tree roots. Decreased allocation of carbon to roots might disrupt root metabolism and rhizosphere organisms. The effects of soil type and shoot O3 exposure on below-ground respiration and soil microbial populations were investigated using container-grown ponderosa pine (Pinus ponderosa Laws.) growing in a low-nutrient soil, or a fertilizer-amended organic potting media, and exposed to one of three levels of O3 for two growing seasons in open-top exposure chambers. A closed system, designed to measure below-ground respiratory activity (CO2 production, O2 consumption and RQ-Respiration Quotient; (CO2 :02 ) of plants growing in pots, was used monthly to monitor below-ground respiration of 3-yr-old ponderosa pine. Although seasonal differences were detected, CO2 production (μmol h-1 g-1 total root d. wt), O2 consumption (μmol h-1 g-1 total root d. wt) and RQ (CO2 :O2 ) increased with increasing O3 exposure level. Seasonal patterns showed increased respiration rates during periods of rapid root growth in spring and early fall. Respiration quotient tended to decrease during known periods of active root growth in control seedlings, but a similar response was not observed in O3 -treated seedlings. Responses to O3 were greatest in the soil-grown plants, which had a lower fertility level than media-grown plants. Although root d. wt was decreased, root: shoot ratios did not change in response to O3 . Soil-grown plants had higher root-shoot ratios than media-grown plants, reflecting the lower fertility of the soil. Plant exposure to O3 was found to affect both active and total populations of soil organisms. In both organic potting media and in soil, biomass of active soil fungi, and the ratio of active-fungal to active-bacterial biomass increased with increasing plant exposure to O3 . The effect of O3 on total fungal and bacterial biomass was not linear: at low O3 levels, total fungal and bacterial biomass increased; at the high O3 level, total fungal and bacterial biomass decreased compared with those of controls. Our results show that O3 exposure to shoots significantly disrupts CO2 production and O2 consumption of soil and roots of ponderosa pine seedlings. Below-ground respiratory differences were thought to be a result of changes in respiratory substrates, carbon refixation within the plant and soil microbial activity. Ozone also changes below-ground RQ, suggesting that O3 substantially disrupts root metabolism and interactions with rhizosphere organisms. Ozone exposure of ponderosa pine grown in different soil types can disrupt below-ground respiration and influence populations of soil organisms without alteration of biomass partitioning between above- and below-ground plant components. Collectively, the effect of O3 on the below-ground system is of concern since it is likely that these changes are accompanied by a change in the ability of root systems to acquire nutrient and water resources and possibly to synthesize amino acids and proteins necessary for normal plant function 
650 4 |a Journal Article 
650 4 |a O3 
650 4 |a microbial respiration 
650 4 |a ponderosa pine 
650 4 |a respiration quotient 
650 4 |a root respiration 
700 1 |a Andersen, C P  |e verfasserin  |4 aut 
773 0 8 |i Enthalten in  |t The New phytologist  |d 1984  |g 136(1997), 4 vom: 18. Aug., Seite 627-643  |w (DE-627)NLM09818248X  |x 1469-8137  |7 nnas 
773 1 8 |g volume:136  |g year:1997  |g number:4  |g day:18  |g month:08  |g pages:627-643 
856 4 0 |u http://dx.doi.org/10.1046/j.1469-8137.1997.00779.x  |3 Volltext 
912 |a GBV_USEFLAG_A 
912 |a SYSFLAG_A 
912 |a GBV_NLM 
912 |a GBV_ILN_350 
951 |a AR 
952 |d 136  |j 1997  |e 4  |b 18  |c 08  |h 627-643