The role of protected areas in land use/land cover change and the carbon cycle in the conterminous United States. (8th August 2017)

• Record Type: Journal Article
• Authors: Lu, Xiaoliang; Zhou, Yuyu; Liu, Yaling; Le Page, Yannick
• Is Part Of: Global change biology. Volume 24:Number 2(2018)
• Page Start: 617
• Page End: 630
• Publication Date: 2017-08-08
• Subjects: carbon cycle -- climate change -- disturbances -- ecosystem modeling -- land use/land cover change -- protected areas; Climatic changes -- Environmental aspects -- Periodicals; Troposphere -- Environmental aspects -- Periodicals; Biodiversity conservation -- Periodicals; Eutrophication -- Periodicals; 551.5
• DOI: 10.1111/gcb.13816
• Languages: English
• ISSNs: 1354-1013

Abstract

Abstract: Protected areas (PAs) cover about 22% of the conterminous United States. Understanding their role on historical land use and land cover change (LULCC) and on the carbon cycle is essential to provide guidance for environmental policies. In this study, we compiled historical LULCC and PAs data to explore these interactions within the terrestrial ecosystem model (TEM). We found that intensive LULCC occurred in the conterminous United States from 1700 to 2005. More than 3 million km 2 of forest, grassland and shrublands were converted into agricultural lands, which caused 10, 607 Tg C release from land ecosystems to atmosphere. PAs had experienced little LULCC as they were generally established in the 20th century after most of the agricultural expansion had occurred. PAs initially acted as a carbon source due to land use legacies, but their accumulated carbon budget switched to a carbon sink in the 1960s, sequestering an estimated 1, 642 Tg C over 1700–2005, or 13.4% of carbon losses in non‐PAs. We also find that PAs maintain larger carbon stocks and continue sequestering carbon in recent years (2001–2005), but at a lower rate due to increased heterotrophic respiration as well as lower productivity associated to aging ecosystems. It is essential to continue efforts to maintain resilient, biodiverse ecosystems and avoid large‐scale disturbances that would release large amounts of carbon in PAs. Abstract : Understanding the role of protected areas (PAs) in historical land use and land cover change (LULCC) and their impacts on carbon cycle is essential to provide guidance for environmental policies. We find PAs acted as a carbon sink and they sequestered >1, 500 Tg C during 1700‐2005, accounting for around 13% of carbon losses in non‐PAs. Our findings call for continuing efforts to enforce PAs and avoid large‐scale disturbances that would release large amounts of carbon in PAs.