title: The Influences of Drought and Land-Cover Conversion on Inter-Annual Variation of NPP in the Three-North Shelterbelt Program Zone of China Based on MODIS Data.
abstract: Terrestrial ecosystems greatly contribute to carbon (C) emission reduction targets through photosynthetic C uptake.Net primary production (NPP) represents the amount of atmospheric C fixed by plants and accumulated as biomass. The Three-North Shelterbelt Program (TNSP) zone accounts for more than 40% of China's landmass. This zone has been the scene of several large-scale ecological restoration efforts since the late 1990s, and has witnessed significant changes in climate and human activities.Assessing the relative roles of different causal factors on NPP variability in TNSP zone is very important for establishing reasonable local policies to realize the emission reduction targets for central government. In this study, we examined the relative roles of drought and land cover conversion(LCC) on inter-annual changes of TNSP zone for 2001-2010. We applied integrated correlation and decomposition analyses to a Standardized Evapotranspiration Index (SPEI) and MODIS land cover dataset. Our results show that the 10-year average NPP within this region was about 420 Tg C. We found that about 60% of total annual NPP over the study area was significantly correlated with SPEI (p<0.05). The LCC-NPP relationship, which is especially evident for forests in the south-central area, indicates that ecological programs have a positive impact on C sequestration in the TNSP zone. Decomposition analysis generally indicated that the contributions of LCC, drought, and other Natural or Anthropogenic activities (ONA) to changes in NPP generally had a consistent distribution pattern for consecutive years. Drought and ONA contributed about 74% and 23% to the total changes in NPP, respectively, and the remaining 3% was attributed to LCC. Our results highlight the importance of rainfall supply on NPP variability in the TNSP zone.
authors.affiliation: Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, P. R. China.
authors.forename: Dailiang
authors.identifier: http://orcid.org/0000-0003-1159-0723
authors.initials: D
authors.lastname: Peng
authors.affiliation: State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, P. R. China.
authors.forename: Chaoyang
authors.initials: C
authors.lastname: Wu
authors.affiliation: Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, P. R. China.
authors.forename: Bing
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Plant Functional Biology and Climate Change Cluster (C3), University of Technology Sydney, Australia.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Huete
authors.affiliation: Geospatial Sciences Center of Excellence, South Dakota State University, Brookings, South Dakota, United States of America.
authors.forename: Xiaoyang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Remote Sensing Science, Jointly Sponsored by Beijing Normal University and Institute of Remote sensing Applications of Chinese Academy of Sciences, Beijing, P. R. China.
authors.forename: Rui
authors.initials: R
authors.lastname: Sun
authors.affiliation: Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, P. R. China.
authors.forename: Liping
authors.initials: L
authors.lastname: Lei
authors.affiliation: Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, P. R. China.
authors.forename: Wenjing
authors.initials: W
authors.lastname: Huang
authors.affiliation: Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, P. R. China.
authors.forename: Liangyun
authors.initials: L
authors.lastname: Liu
authors.affiliation: Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, P. R. China.
authors.forename: Xinjie
authors.initials: X
authors.lastname: Liu
authors.affiliation: College of geography, Chongqing Normal University, Chongqing, P. R. China.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.affiliation: Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, P. R. China.
authors.forename: Shezhou
authors.initials: S
authors.lastname: Luo
authors.affiliation: Department of Earth and Environmental Engineering, Columbia University, New York, New York, United States of America.
authors.forename: Bin
authors.initials: B
authors.lastname: Fang
mesh_terms: D000465:Algorithms; D018533:Biomass; D002244:Carbon / Q000032:analysis; D002681:China; D002980:Climate; D055864:Droughts; D017753:Ecosystem; D006802:Human Activities; D006801:Humans; D008962:Models, Theoretical; D015203:Reproducibility of Results
chemical_list: D002244:Carbon