Soil nutrient availability alters tree carbon allocation dynamics during drought

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Drought alters allocation patterns of carbon (C) and nutrients in trees and eventually impairs tree functioning. Elevated soil nutrient availability might alter the response of trees to drought. We hypothesize that increased soil nutrient availability stimulates root metabolism and C allocation to belowground tissues under drought stress. To test this hypothesis, we subjected 3-year-old Pinus sylvestris L. saplings in open-top chambers during two subsequent years to drought using three different water treatments (100, 20 and 0% plant available water in the soil) and two soil nutrient regimes (ambient and nitrogen-phosphorus-potassium (N-P-K) fertilization corresponding to 5 g N m-2 year-1) and released drought thereafter. We conducted a 15N and 13C labeling experiment during the peak of the first-year drought by injecting 15N labeled fertilizer in the soil and exposing the tree canopies to 13C labeled CO2. The abundance of the N and C isotopes in the roots, stem and needles was assessed during the following year. Carbon uptake was slightly lower in drought-stressed trees, and extreme drought inhibited largely the N uptake and transport. Carbon allocation to belowground tissues was decreased under drought, but not in combination with fertilization. Our results indicate a potential positive feedback loop, where fertilization improved the metabolism and functioning of the roots, stimulating C allocation to belowground tissues. This way, soil nutrients compensated for drought-induced loss of root functioning, mitigating drought stress of trees.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:41

Enthalten in:

Tree physiology - 41(2021), 5 vom: 14. Mai, Seite 697-707

Sprache:

Englisch

Beteiligte Personen:

Schönbeck, Leonie [VerfasserIn]
Li, Mai-He [VerfasserIn]
Lehmann, Marco M [VerfasserIn]
Rigling, Andreas [VerfasserIn]
Schaub, Marcus [VerfasserIn]
Hoch, Günter [VerfasserIn]
Kahmen, Ansgar [VerfasserIn]
Gessler, Arthur [VerfasserIn]

Links:

Volltext

Themen:

13C
15N
7440-44-0
Carbon
Carbon allocation
Drought
Isotopes
Journal Article
N762921K75
Nitrogen
Nitrogen allocation
Pinus sylvestris
Research Support, Non-U.S. Gov't
Soil

Anmerkungen:

Date Completed 27.05.2021

Date Revised 27.05.2021

published: Print

Citation Status MEDLINE

doi:

10.1093/treephys/tpaa139

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM316484776