z-logo
Premium
Long‐term nitrogen deposition linked to reduced water use efficiency in forests with low phosphorus availability
Author(s) -
Huang Zhiqun,
Liu Bao,
Davis Murray,
Sardans Jordi,
Peñuelas Josep,
Billings Sharon
Publication year - 2016
Publication title -
new phytologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.742
H-Index - 244
eISSN - 1469-8137
pISSN - 0028-646X
DOI - 10.1111/nph.13785
Subject(s) - nitrogen , phosphorus , deposition (geology) , herbarium , subtropics , carbon fibers , tropical and subtropical moist broadleaf forests , soil water , environmental chemistry , agronomy , environmental science , chemistry , ecology , botany , biology , materials science , paleontology , organic chemistry , sediment , composite number , composite material
Summary The impact of long‐term nitrogen (N) deposition is under‐studied in phosphorus (P)‐limited subtropical forests. We exploited historically collected herbarium specimens to investigate potential physiological responses of trees in three subtropical forests representing an urban‐to‐rural gradient, across which N deposition has probably varied over the past six decades. We measured foliar [N] and [P] and stable carbon (δ 13 C), oxygen (δ 18 O) and nitrogen (δ 15 N) isotopic compositions in tissue from herbarium specimens of plant species collected from 1947 to 2014. Foliar [N] and N : P increased, and δ 15 N and [P] decreased in the two forests close to urban centers. Consistent with recent studies demonstrating that N deposition in the region is 15 N‐depleted, these data suggest that the increased foliar [N] and N : P, and decreased [P], may be attributable to atmospheric deposition and associated enhancement of P limitation. Estimates of intrinsic water use efficiency calculated from foliar δ 13 C decreased by c . 30% from the 1950s to 2014, contrasting with multiple studies investigating similar parameters in N‐limited forests. This effect may reflect decreased photosynthesis, as suggested by a conceptual model of foliar δ 13 C and δ 18 O. Long‐term N deposition may exacerbate P limitation and mitigate projected increases in carbon stocks driven by elevated CO 2 in forests on P‐limited soils.

This content is not available in your region!

Continue researching here.

Having issues? You can contact us here