Influence of chronic and excessive nitrogen influx on forest ecosystems connected to the Tokyo metropolitan area

The impact of large cities on the environment is a concern not only on the environment of the urban area but also on the environment of the surrounding areas connected to the city and even the global environment. Therefore, it is necessary to determine the impact of large cities on the surrounding e...

Full description

Bibliographic Details
Main Authors: Yuko Itoh, Masahiro Kobayashi, Toru Okamoto, Akihiro Imaya, Yoshimi Sakai, Shuichiro Yoshinaga
Format: Article
Language:English
Published: Elsevier 2021-08-01
Series:Ecological Indicators
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S1470160X21004362
_version_ 1818937346347761664
author Yuko Itoh
Masahiro Kobayashi
Toru Okamoto
Akihiro Imaya
Yoshimi Sakai
Shuichiro Yoshinaga
author_facet Yuko Itoh
Masahiro Kobayashi
Toru Okamoto
Akihiro Imaya
Yoshimi Sakai
Shuichiro Yoshinaga
author_sort Yuko Itoh
collection DOAJ
description The impact of large cities on the environment is a concern not only on the environment of the urban area but also on the environment of the surrounding areas connected to the city and even the global environment. Therefore, it is necessary to determine the impact of large cities on the surrounding environment at various scales. Owing to human activities in megacities, various air pollutants are emitted into the atmosphere from fixed and mobile emission sources, causing severe air pollution problems. In particular, excessive anthropogenic nitrogen (N) emissions have become an urgent environmental issue that needs to be addressed globally. The impact of increased N emissions on a global scale also extends to forest ecosystems. The excessive N influx into forested areas alters the N dynamics of the ecosystem. To determine the impact of the Tokyo metropolitan area, one of the megacities in the world, on the surrounding environment, we investigated the influxes of N and sulfur (S) from bulk precipitation (BP) and throughfall (TF) at 12 forest sites surrounding the Tokyo metropolitan area. At the majority of the forest sites, atmospherically derived N and S influxes from TF were greater than those from BP. The N influx from TF in the forested area was equal to or greater than the amount of N deposited in the urban area. Air pollutants, mainly gases and aerosols, emitted from the Tokyo metropolitan area were transported to the inland forested areas by mesoscale meteorological and topographical factors. In addition, the forest canopy structure efficiently captured the dry deposition and accelerated the influx of N, particularly from the atmosphere into the forest ecosystems. The chronic and excess N influx due to human activities in the megacity has already resulted in high nitrate leaching at forested stream sites bordering the Tokyo metropolitan area.
first_indexed 2024-12-20T05:50:30Z
format Article
id doaj.art-11372f03cbeb4c5db0286c050786eecd
institution Directory Open Access Journal
issn 1470-160X
language English
last_indexed 2024-12-20T05:50:30Z
publishDate 2021-08-01
publisher Elsevier
record_format Article
series Ecological Indicators
spelling doaj.art-11372f03cbeb4c5db0286c050786eecd2022-12-21T19:51:11ZengElsevierEcological Indicators1470-160X2021-08-01127107771Influence of chronic and excessive nitrogen influx on forest ecosystems connected to the Tokyo metropolitan areaYuko Itoh0Masahiro Kobayashi1Toru Okamoto2Akihiro Imaya3Yoshimi Sakai4Shuichiro Yoshinaga5Forestry and Forest Products Research Institute, 1-Mtsunosato, Tsukuba, Ibaraki 305-8687, Japan; Corresponding author.Forestry and Forest Products Research Institute, 1-Mtsunosato, Tsukuba, Ibaraki 305-8687, JapanKansai Research Center, Forestry and Forest Products Research Institute, 68 Nagaikyutaroh, Momoyama, Fushimi, Kyoto, Kyoto 612-0855, JapanJapan International Research Center for Agricultural Sciences, 1-1 Ohwashi, Tsukuba, Ibaraki 305-8686 JapanKyusyu Research Center, Forestry and Forest Products Research Institute, 4-11-16 Kurokami, Chuo, Kumamoto, Kumamoto 860-0862, JapanTama Forest Science Garden, Forestry and Forest Products Research Institute, 1833-81 Todori-machi, Hachioji, Tokyo 193-0843, JapanThe impact of large cities on the environment is a concern not only on the environment of the urban area but also on the environment of the surrounding areas connected to the city and even the global environment. Therefore, it is necessary to determine the impact of large cities on the surrounding environment at various scales. Owing to human activities in megacities, various air pollutants are emitted into the atmosphere from fixed and mobile emission sources, causing severe air pollution problems. In particular, excessive anthropogenic nitrogen (N) emissions have become an urgent environmental issue that needs to be addressed globally. The impact of increased N emissions on a global scale also extends to forest ecosystems. The excessive N influx into forested areas alters the N dynamics of the ecosystem. To determine the impact of the Tokyo metropolitan area, one of the megacities in the world, on the surrounding environment, we investigated the influxes of N and sulfur (S) from bulk precipitation (BP) and throughfall (TF) at 12 forest sites surrounding the Tokyo metropolitan area. At the majority of the forest sites, atmospherically derived N and S influxes from TF were greater than those from BP. The N influx from TF in the forested area was equal to or greater than the amount of N deposited in the urban area. Air pollutants, mainly gases and aerosols, emitted from the Tokyo metropolitan area were transported to the inland forested areas by mesoscale meteorological and topographical factors. In addition, the forest canopy structure efficiently captured the dry deposition and accelerated the influx of N, particularly from the atmosphere into the forest ecosystems. The chronic and excess N influx due to human activities in the megacity has already resulted in high nitrate leaching at forested stream sites bordering the Tokyo metropolitan area.http://www.sciencedirect.com/science/article/pii/S1470160X21004362NitrogenSulfurBulk precipitationThroughfallCanopy structureMegacity
spellingShingle Yuko Itoh
Masahiro Kobayashi
Toru Okamoto
Akihiro Imaya
Yoshimi Sakai
Shuichiro Yoshinaga
Influence of chronic and excessive nitrogen influx on forest ecosystems connected to the Tokyo metropolitan area
Ecological Indicators
Nitrogen
Sulfur
Bulk precipitation
Throughfall
Canopy structure
Megacity
title Influence of chronic and excessive nitrogen influx on forest ecosystems connected to the Tokyo metropolitan area
title_full Influence of chronic and excessive nitrogen influx on forest ecosystems connected to the Tokyo metropolitan area
title_fullStr Influence of chronic and excessive nitrogen influx on forest ecosystems connected to the Tokyo metropolitan area
title_full_unstemmed Influence of chronic and excessive nitrogen influx on forest ecosystems connected to the Tokyo metropolitan area
title_short Influence of chronic and excessive nitrogen influx on forest ecosystems connected to the Tokyo metropolitan area
title_sort influence of chronic and excessive nitrogen influx on forest ecosystems connected to the tokyo metropolitan area
topic Nitrogen
Sulfur
Bulk precipitation
Throughfall
Canopy structure
Megacity
url http://www.sciencedirect.com/science/article/pii/S1470160X21004362
work_keys_str_mv AT yukoitoh influenceofchronicandexcessivenitrogeninfluxonforestecosystemsconnectedtothetokyometropolitanarea
AT masahirokobayashi influenceofchronicandexcessivenitrogeninfluxonforestecosystemsconnectedtothetokyometropolitanarea
AT toruokamoto influenceofchronicandexcessivenitrogeninfluxonforestecosystemsconnectedtothetokyometropolitanarea
AT akihiroimaya influenceofchronicandexcessivenitrogeninfluxonforestecosystemsconnectedtothetokyometropolitanarea
AT yoshimisakai influenceofchronicandexcessivenitrogeninfluxonforestecosystemsconnectedtothetokyometropolitanarea
AT shuichiroyoshinaga influenceofchronicandexcessivenitrogeninfluxonforestecosystemsconnectedtothetokyometropolitanarea