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Effects of vegetation heterogeneity and surface topography on spatial scaling of net primary productivity

J. M. Chen, X. Chen, W. Ju
2013 Biogeosciences  
Land cover fraction is the most important vegetation factor to be considered in NPP spatial scaling, and slope is the most important topographical factor for NPP spatial scaling especially in mountainous  ...  </strong> Due to the heterogeneous nature of the land surface, spatial scaling is an inevitable issue in the development of land models coupled with low-resolution Earth system models (ESMs) for predicting  ...  spatial variations of carbon and water fluxes under the influence of topography.  ... 
doi:10.5194/bg-10-4879-2013 fatcat:gpewxghk4rg43f7jp3cxswgobe

Effects of vegetation heterogeneity and surface topography on spatial scaling of net primary productivity

J. M. Chen, X. Chen, W. Ju
2013 Biogeosciences Discussions  
Technical assistance of Gang Mo and Andrey Bulinko in coupling the BEPS and Terrainlab was particularly important for this work.  ...  The authors are indebted to Qingjiu Tian, Fengming Hui and Xiuqin Fang at Nanjing University for assistance in the atmospheric correction and land cover classification.  ...  variations of carbon and water fluxes under the influence of topography.  ... 
doi:10.5194/bgd-10-4225-2013 fatcat:mpuole62brhajmbomacwmy3a7e

Evaluating Trends of Land Productivity Change and Their Causes in the Han River Basin, China: In Support of SDG Indicator 15.3.1

Yanxia Hu, Changqing Wang, Xingxiu Yu, Shengzhou Yin
2021 Sustainability  
The spatial heterogeneity of land NPP was evident, with high values in the west and low values in the east.  ...  In addition, the spatial heterogeneity of factors influencing land NPP change was explored using a multiscale geographically weighted regression (MGWR) model.  ...  The spatial-temporal dynamics and sustainability of land NPP change in the Han River Basin under the influence of human activities, as well as on longer time scales, have not been fully studied.  ... 
doi:10.3390/su132413664 fatcat:ncfjalh7bbgkrlyvndxd2t576y

A modeling and spatio-temporal analysis framework for monitoring environmental change using NPP as an ecosystem indicator

Robert Crabtree, Christopher Potter, Randall Mullen, Jennifer Sheldon, Shengli Huang, Joshua Harmsen, Ann Rodman, Cathie Jean
2009 Remote Sensing of Environment  
These results supported regional and national trends of NPP in relation to carbon fluxes and lag effects of climate.  ...  The EMAS is evaluated and assessed with an application example in Yellowstone National Park aimed at identifying the causes and consequences of drought.  ...  The influence of fire on NPP in 2001 is assessed by a 'fire influence index' calculated as the burn severity index divided by the number of years since the fire.  ... 
doi:10.1016/j.rse.2008.12.014 fatcat:hl6whpt2y5ffhi2kauv4tp5s34

Vegetation Productivity Dynamics in Response to Climate Change and Human Activities under Different Topography and Land Cover in Northeast China

Hui Li, Hongyan Zhang, Qixin Li, Jianjun Zhao, Xiaoyi Guo, Hong Ying, Guorong Deng, Wu Rihan, Shuling Wang
2021 Remote Sensing  
The results are significant for understanding the factors influencing the vegetation productivity dynamics in NEC and can provide a reference for governments to implement projects to improve the ecosystem  ...  In this study, we employed actual NPP (ANPP), potential NPP (PNPP), and human activity-induced NPP (HNPP) based on the Hurst exponent and statistical analysis to analyze the characteristics of vegetation  ...  Acknowledgments: The authors would like to thank the Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains, Ministry of Education, and Urban Remote Sensing Application  ... 
doi:10.3390/rs13050975 doaj:f55dd82d12314e8caec17a36da4fb5cf fatcat:rges43h5qjhm5dfn7ilrzu2yay

Mapping ecosystem services for China's ecoregions with a biophysical surrogate approach

Liwei Zhang, Yihe Lü, Bojie Fu, Zhibao Dong, Yuan Zeng, Bingfang Wu
2017 Landscape and Urban Planning  
Thus the simple surrogate approach is suitable for the rapid assessment and long-term dynamic surveillance of ESs at broad spatial scales, and for tasks such as priority setting or performance assessments  ...  The results revealed the spatial distribution patterns and time trends of the ESs of the eleven ecoregions in China.  ...  In the north of the Loess Plateau ecoregion, where farmland was converted to grassland or forest under the promotion of the Grain for Green Project, vegetation in the area recovered significantly , and  ... 
doi:10.1016/j.landurbplan.2016.12.015 fatcat:sdmtx6x345e2fmjg7bwamemiye

Comparing Process-Based Net Primary Productivity Models in a Mediterranean Watershed

C. Donmez, S. Berberoglu, M. Forrest, A. Cilek, T. Hickler
2013 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
The effect of vegetation distribution on the accuracy of models was examined.  ...  ABSTRACT: The aim of this study was to compare the estimation capability of two different process-based NPP models (CASA and LPJ-GUESS) in a Mediterranean watershed.  ...  The complexity of its terrain in respect to the soil types and topography greatly influence reflectance from sparse cover of the Mediterranean forests.  ... 
doi:10.5194/isprsarchives-xl-7-w2-67-2013 fatcat:utsgy5ncffh5tof7tz42udowk4

Assessment of Drought Impact on Net Primary Productivity in the Terrestrial Ecosystems of Mongolia from 2003 to 2018

Lkhagvadorj Nanzad, Jiahua Zhang, Battsetseg Tuvdendorj, Shanshan Yang, Sonam Rinzin, Foyez Ahmed Prodhan, Til Prasad Pangali Sharma
2021 Remote Sensing  
In contrast, forest and shrubland were the least affected vegetation types.  ...  The Boreal Ecosystem Productivity Simulator (BEPS)-derived NPP was computed to assess changes in NPP during the 16 years, and the impacts of drought on the NPP of Mongolian terrestrial ecosystems was quantitatively  ...  The objectives of this study were to (1) quantify the spatial and seasonal (growing season) variability of drought events, (2) examine the spatial and temporal variations in terrestrial NPP, (3) assess  ... 
doi:10.3390/rs13132522 fatcat:3ulssosgk5dqbbolkqt2r5afma

Evaluation of MODIS GPP over a complex ecosystem in East Asia: A case study at Gwangneung flux tower in Korea

Changsub Shim, Jiyoun Hong, Jinkyu Hong, Youngwook Kim, Minseok Kang, Bindu Malla Thakuri, Yongwon Kim, Junghwa Chun
2014 Advances in Space Research  
To examine the influence of subgrid scale heterogeneity on GPP estimates over the MODIS scale, the individual vegetation type and its area within a corresponding MODIS pixel were identified using a national  ...  The accuracy of meteorological variables and the impact of the very cloudy conditions in East Asia also need to be assessed.  ...  We also thank Korea Environment Institute (KEI) for the institutional support for the research.  ... 
doi:10.1016/j.asr.2014.08.031 fatcat:4yvnpbym7rcaldpvhyeuvwpkx4

İklim Değişikliği Senaryoları Altında Konumsal Modelleme Kullanarak Türkiye'nin Çevresel Risk Analizi: Net Birincil Üretim Örneği

Süha BERBEROĞLU, Cenk DÖNMEZ, Ahmet ÇİLEK
2016 Çukurova Üniversitesi Mühendislik-Mimarlık Fakültesi Dergisi  
A comprehensive data set including percentage of tree cover, land cover map, soil texture, NDVI (Normalized Difference Vegetation Index) and climate variables were used to constitute the model.  ...  The aim of this study is to estimate the response of NPP to regional climate changes in Turkey using a biogeochemical modelling approach.  ...  Environmental Risk Analysis of Turkey under Climate Change Scenarios using Spatial Modelling: Application of Net METHODOLOGY The CASA model was used in this study to estimate present and future NPP in  ... 
doi:10.21605/cukurovaummfd.316723 fatcat:cmax6n7kijbvvo3sc23niiqsvm

Modelling the spatial pattern of net primary productivity in Chinese forests

Hong Jiang, Michael J Apps, Yanli Zhang, Changhui Peng, Paul M Woodard
1999 Ecological Modelling  
The results reported here demonstrate the usefulness of spatial analyses techniques for improving the accuracy of NPP estimates and our understanding of NPP spatial patterns and dynamics in forest ecosystems  ...  The spatial patterns of biomass and net primary productivity in China's forests were estimated using empirical data sets, remote sensing methods, and climate-vegetation models, and were analysed within  ...  The senior author also wishes to acknowledge support from the Canadian Forest Service (CFS) and the Network Center of Excellence for Sustainable Forest Management, University of Alberta.  ... 
doi:10.1016/s0304-3800(99)00142-8 fatcat:coq7v3l3jve2dl652dcf2uomlu

CONTINENTAL SCALE VARIABILITY IN ECOSYSTEM PROCESSES: MODELS, DATA, AND THE ROLE OF DISTURBANCE

David S. Schimel, VEMAP Participants, B. H. Braswell
1997 Ecological Monographs  
The VEMAP models simulated spatial variability in ecosystem processes in substantially different ways, reflecting the models' differing implementations of multiple resource limitation of NPP.  ...  Knowledge of the effects of disturbance (human and natural) and spatial data describing disturbance regimes are needed for spatial modeling of ecosystems.  ...  The objectives of this paper were twofold: to utilize spatial variability in model responses to diagnose the importance of different underlying mechanisms, and to explore methodology and data sets for  ... 
doi:10.1890/0012-9615(1997)067[0251:csviep]2.0.co;2 fatcat:q56rv72lcfeq5dieshxyyvzvbe

Continental Scale Variability in Ecosystem Processes: Models, Data, and the Role of Disturbance

David S. Schimel, Vemap Participants, B. H. Braswell
1997 Ecological Monographs  
The VEMAP models simulated spatial variability in ecosystem processes in substantially different ways, reflecting the models' differing implementations of multiple resource limitation of NPP.  ...  Knowledge of the effects of disturbance (human and natural) and spatial data describing disturbance regimes are needed for spatial modeling of ecosystems.  ...  The objectives of this paper were twofold: to utilize spatial variability in model responses to diagnose the importance of different underlying mechanisms, and to explore methodology and data sets for  ... 
doi:10.2307/2963515 fatcat:jzwthng6a5gzdged5q6fd7ghrm

Spatial variability of aboveground net primary production for a forested landscape in northern Wisconsin

S N Burrows, S T Gower, J M Norman, G Diak, D S Mackay, D E Ahl, M K Clayton
2003 Canadian Journal of Forest Research  
The objectives of this study were to measure aboveground NPP (NPP A ) for a land surface in northern Wisconsin, examine the spatial patterns of NPP A and its components, and correlate NPP A with vegetation  ...  The spatial range estimates for the three NPP components and NPP A differed significantly from each other, suggesting that different factors are influencing the components of NPP.  ...  Numerous undergraduate students assisted with the installation of the plots, NPP measurements, litterfall collecting and processing. Thanks to Dr. V.C.  ... 
doi:10.1139/x03-124 fatcat:xwcqif3gwjb67irqf52nfa2u3e

Effects of Environmental Factors on the Changes in MODIS NPP along DEM in Global Terrestrial Ecosystems over the Last Two Decades

Zhaoqi Wang, Hong Wang, Tongfang Wang, Lina Wang, Xiaotao Huang, Kai Zheng, Xiang Liu
2022 Remote Sensing  
Vegetation is an important part of the terrestrial ecosystem, and its net primary productivity (NPP) is an important variable in the exchange of materials and energy in the terrestrial ecosystem.  ...  However, the effect of climate variation on the spatial pattern of zonal distribution of NPP has remained unclear over the past two decades.  ...  This situation raises a scientific question as to whether the elevation pattern of NPP has changed under the influence of global warming.  ... 
doi:10.3390/rs14030713 fatcat:tvxh6dwk3vexvle7zzhzy5xnhm
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