Improving remote sensing-based net primary production estimation in the grazed land with defoliation formulation model
Remote sensing (RS) technologies provide robust techniques for quantifying net primary productivity (NPP) which is a key component of ecosystem production management. Applying RS, the confounding effects of carbon consumed by livestock grazing were neglected by previous studies, which created uncertainties and underestimation of NPP for the grazed lands. The grasslands in Xinjiang were selected as a case study to improve the RS based NPP estimation. A defoliation formulation model (DFM) based on RS is developed to evaluate the extent of underestimated NPP between 1982 and 2011. The estimates were then used to examine the spatiotemporal patterns of the calculated NPP. Results show that average annual underestimated NPP was 55.74 gC·m-2yr-1 over the time period understudied, accounting for 29.06% of the total NPP for the Xinjiang grasslands. The spatial distribution of underestimated NPP is related to both grazing intensity and time. Data for the Xinjiang grasslands show that the average annual NPP was 179.41 gC·m-2yr-1, the annual NPP with an increasing trend was observed at a rate of 1.04 gC·m-2yr-1 between 1982 and 2011. The spatial distribution of NPP reveals distinct variations from high to low encompassing the geolocations of the Tianshan Mountains, northern and southern Xinjiang Province and corresponding with mid-mountain meadow, typical grassland, desert grassland, alpine meadow, and saline meadow grassland types. This study contributes to improving RS-based NPP estimations for grazed land and provides a more accurate data to support the scientific management of fragile grassland ecosystems in Xinjiang.
KeywordsRemote sensing Defoliation formulation model Net primary production Grazed land Spatial-temporal patterns Xinjiang
Unable to display preview. Download preview PDF.
This work was supported by the international Partnership Program of the Chinese Academy of Science (Grant No. 131965KYSB20160004), the National Natural Science Foundation of China (Grant No. U1803243), the Network Plan of the Science and Technology Service, Chinese Academy of Sciences (STS Plan) and Qinghai innovation platform construction project (2017-ZJ-Y20).
- Digital elevation data set of China. Available online at: http://www.wdc.cn/wdcdrre (Accessed on 2018-03-21) Global Livestock Information System (GLIS). Available online at: http://www.fao.org/docrep/010/a1259e/a1259e00.htm (Accessed on 2018-03-06) The standard of Chinese Ministry of Agriculture. Available online at: http://www.chinaforage.com/standard/zaixuliang.htm (Accessed on 2018-04-11) Xinjiang Yearbook. Available online at: http://www.xjtj.gov.cn/stats data/50years/(Accessed on 2018-04-16
- Banks T, Doman S (2001) Kazakh nomads, rangeland policy and the environment in Altay: insights from new range ecology. In: Second International Convention of Asia Scholars, Free University, Berlin.Google Scholar
- Council NR (1985) Nutrient requirements of sheep, National Academies.Google Scholar
- Dangal SR (2017) Interactive Effects of Climate Change and Grazing on Ecosystem Productivity and Greenhouse Gas Balance at Multiple Scales from Landscape to Global. Auburn University, Alabama, The Unite StatesGoogle Scholar
- Dong YQ, Sun ZJ, An SH, et al. (2017) Natural Restoration of Degraded Grassland on the Northern Xinjiang, China: The Restoration Difference between Lightly and Moderately Degraded Deserts under Grazing Exclusion. Fresenius Environmental Bulletin 26(6): 3845–3855.Google Scholar
- Herrero M, Thornton PK(2013) Livestock and global change: emerging issues for sustainable food systems. Proceedings of the National Academy of Sciences: 110, 20878–20881.Google Scholar
- Kawamura K, Akiyama T, Yokota HO, et al. (2005) Quantifying grazing intensities using geographic information systems and satellite remote sensing in the Xilingol steppe region, Inner Mongolia, China. Agriculture, Ecosystems & Environment 107(1): 83–93. https://doi.org/10.1016/j.agee.2004.09.008 Google Scholar
- Keeling R, Piper S, Bollenbacher A, et al. (2009) Atmospheric carbon dioxide record from Mauna Loa. Oak Ridge National Laboratory (ORNL), United States.Google Scholar
- Osem Y, Perevolotsky A, Kigel J (2002) Grazing effect on diversity of annual plant communities in a semi‐arid rangeland: interactions with small ‐ scale spatial and temporal variation in primary productivity. Journal of Ecology 90(6): 936–946. https://doi.org/10.1046/j.1365-2745.2002.00730.x Google Scholar
- Quaife T, Quegan S, Disney M, et al. (2008) Impact of land cover uncertainties on estimates of biospheric carbon fluxes. Global Biogeochemical Cycles 22(4). https://doi.org/10.1029/2007GB003097.
- Ren X, Zheng JH, Mu C, et al. (2017) Correlation analysis of the spatial-temporal variation of grassland net primary productivity and climate factors in Xinjiang in the past 15 years. Ecological Science 36(3): 43–51. (In Chinese)Google Scholar
- Steinfeld H, Gerber P, Wassenaar T, et al. (2006) Livestock’s long shadow: environmental issues and options, Food & Agriculture Org.Google Scholar
- Wang JB, Liu JY, Shao QQ, et al. (2009) Spatial-temporal patterns of net primary productivity for 1988–2004 based on GLOPEMCEVSA model in the" Three-River Headwaters" region of Qinghai Province, China. Journal of Plant Ecology 33(2): 254–269. (In Chinese) https://doi.org/10.3773/j.issn.1005-264x.2009.02.003 Google Scholar
- Zeng FW, Collatz GJ, Pinzon JE, et al. (2013) Evaluating and quantifying the climate-driven interannual variability in Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index (NDVI3g) at global scales. Remote Sensing 5(8): 3918–3950. https://doi.org/10.3390/rs5083918 Google Scholar
- Zhang C, Tian HQ, Liu J, et al. (2005) Pools and distributions of soil phosphorus in China. Global Biogeochemical Cycles 19(1). https://doi.org/10.1029/2004GB002296
- Zhou DC, Luo GP, Han QF, et al. (2012) Impacts of grazing and climate change on the aboveground net primary productivity of mountainous grassland ecosystems along altitudinal gradients over the Northern Tianshan Mountains, China. Acta Ecologica Sinica 32(1): 81–92. (In Chinese) https://doi.org/10.5846/stxb201010141445 Google Scholar
- Zhu Z, Bi J, Pan Y, et al. (2013) Global data sets of vegetation leaf area index (LAI) 3g and Fraction of Photosynthetically Active Radiation (FPAR) 3g derived from Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index (NDVI3g) for the period 1981 to 2011. Remote Sensing 5(2): 927–948. https://doi.org/10.3390/rs5020927 Google Scholar