The Relative Contributions of Climate and Grazing on the Dynamics of Grassland NPP and PUE on the Qinghai-Tibet Plateau
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Area
2.2. Data Collection and Process Method
2.3. NPP Simulation and Validation
2.4. PUE Calculation
2.5. Grazing Intensity Calculation
2.6. Data Analysis
3. Results
3.1. Spatiotemporal Patterns of Climate Factors and Grazing Intensity
3.2. Spatiotemporal Patterns of NPP
3.3. Spatiotemporal Patterns of PUE
3.4. Relationships of NPP and PUE with Climatic Factors and Grazing Intensity
3.5. Relative Contributions of Climatic Factors and Grazing Intensity
4. Discussion
4.1. Warmer and Wetter Climate Promotes NPP Increases on the QTP
4.2. The Spatiotemporal Variation of PUE
4.3. The Effects of GI on Vegetation Growth
4.4. Limitations and Uncertainties
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
- Radu, D.D.; Duval, T.P. Precipitation Frequency Alters Peatland Ecosystem Structure and CO2 Exchange: Contrasting Effects on Moss, Sedge, and Shrub Communities. Glob. Chang. Biol. 2018, 24, 2051–2065. [Google Scholar] [CrossRef]
- DeFries, R. Past and Future Sensitivity of Primary Production to Human Modification of the Landscape. Geophys. Res. Lett. 2002, 29, 36-1–36-4. [Google Scholar] [CrossRef]
- Vitousek, P.M.; Mooney, H.A.; Lubchenco, J.; Melillo, J.M. Human Domination of Earth’s Ecosystems. Science 1997, 277, 494–499. [Google Scholar] [CrossRef] [Green Version]
- Venter, O.; Sanderson, E.W.; Magrach, A.; Allan, J.R.; Beher, J.; Jones, K.R.; Possingham, H.P.; Laurance, W.F.; Wood, P.; Fekete, B.M. Sixteen Years of Change in the Global Terrestrial Human Footprint and Implications for Biodiversity Conservation. Nat. Commun. 2016, 7, 12558. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Seiferling, I.; Proulx, R.; Wirth, C. Disentangling the Environmental-Heterogeneity Species-Diversity Relationship Along a Gradient of Human Footprint. Ecology 2014, 95, 2084–2095. [Google Scholar] [CrossRef] [PubMed]
- Piao, S.; Wang, X.; Park, T.; Chen, C.; Lian, X.; He, Y.; Bjerke, J.W.; Chen, A.; Ciais, P.; Tømmervik, H.; et al. Characteristics, Drivers and Feedbacks of Global Greening. Nat. Rev. Earth Environ. 2020, 1, 14–27. [Google Scholar] [CrossRef]
- Gil, M.A.; Baskett, M.L.; Munch, S.B.; Hein, A.M. Fast Behavioral Feedbacks Make Ecosystems Sensitive to Pace and Not Just Magnitude of Anthropogenic Environmental Change. Proc. Natl. Acad. Sci. USA 2020, 117, 25580–25589. [Google Scholar] [CrossRef]
- Chen, T.; Bao, A.M.; Jiapaer, G.; Guo, H.; Zheng, G.X.; Jiang, L.L.; Chang, C.; Tuerhanjiang, L. Disentangling the Relative Impacts of Climate Change and Human Activities on Arid and Semi-Arid Grasslands in Central Asia during 1982–2015. Sci. Total Environ. 2019, 653, 1311–1325. [Google Scholar] [CrossRef]
- Curlock, J.M.O.S.; Hall, D.O. The Global Carbon Sink: A Grassland Perspective. Glob. Chang. Biol. 2010, 4, 229–233. [Google Scholar] [CrossRef] [Green Version]
- Xie, G.D.; Zhang, Y.L.; Lu, C.X. Study on Valuation of Rangeland Ecosystem Services of China. J. Natl. Resour. 2001, 16, 47–53. [Google Scholar]
- Gang, C.; Zhou, W.; Chen, Y.; Wang, Z.; Sun, Z.; Li, J.; Qi, J.; Odeh, I. Quantitative Assessment of the Contributions of Climate Change and Human Activities on Global Grassland Degradation. Environ. Earth Sci. 2014, 72, 4273–4282. [Google Scholar] [CrossRef]
- Gao, Y.; Zhou, X.; Wang, Q.; Wang, C.; Zhan, Z.; Chen, L.; Yan, J.; Qu, R. Vegetation Net Primary Productivity and Its Response to Climate Change During 2001–2008 in the Tibetan Plateau. Sci. Total Environ. 2013, 444, 356–362. [Google Scholar] [CrossRef]
- Nemani, R.R.; Keeling, C.D.; Hashimoto, H.; Jolly, W.M.; Piper, S.C.; Tucker, C.J.; Myneni, R.B.; Running, S.W. Climate-Driven Increases in Global Terrestrial Net Primary Production from 1982 to 1999. Science 2003, 300, 1560–1563. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Ling, L.; Xin, L.; Huang, C.L.; Veroustraete, F. Analysis of the Spatio-Temporal Characteristics of Water Use Efficiency of Vegetation in West China. J. Glaciol. Geocryol. 2007, 29, 777–784. [Google Scholar]
- Hu, Z.; Yu, G.; Fan, J.; Zhong, H.; Wang, S.; Li, S. Precipitation-Use Efficiency Along a 4500-km Grassland Transect. Glob. Ecol. Biogeogr. 2010, 19, 842–851. [Google Scholar]
- Siepielski, A.M.; Morrissey, M.B.; Buoro, M.; Carlson, S.M.; Caruso, C.M.; Clegg, S.M.; Coulson, T.; DiBattista, J.; Gotanda, K.M.; Francis, C.D.; et al. Precipitation Drives Global Variation in Natural Selection. Science 2017, 355, 959–962. [Google Scholar] [CrossRef] [Green Version]
- Knapp, A.K.; Fay, P.A.; Blair, J.M.; Collins, S.L.; Smith, M.D.; Carlisle, J.D.; Harper, C.W.; Danner, B.T.; Lett, M.S.; McCarron, J.K. Rainfall Variability, Carbon Cycling, and Plant Species Diversity in a Mesic Grassland. Science 2002, 298, 2202–2205. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Wang, S.; Zhang, B.; Yang, Q.; Chen, G.; Yang, B.; Lu, L.; Shen, M.; Peng, Y. Responses of Net Primary Productivity to Phenological Dynamics in the Tibetan Plateau, China. Agric. For. Meteorol. 2017, 232, 235–246. [Google Scholar] [CrossRef]
- Piao, S.; Friedlingstein, P.; Ciais, P.; Viovy, N.; Demarty, J. Growing Season Extension and Its Impact on Terrestrial Carbon Cycle in the Northern Hemisphere Over the Past 2 Decades. Glob. Biogeochem. Cycles 2007, 21, 116–123. [Google Scholar] [CrossRef]
- Huxman, T.E.; Smith, M.D.; Fay, P.A.; Knapp, A.K.; Shaw, M.R.; Loik, M.E.; Smith, S.D.; Tissue, D.T.; Zak, J.C.; Weltzin, J.F.; et al. Convergence Across Biomes to a Common Rain-Use Efficiency. Nature 2004, 429, 651–654. [Google Scholar] [CrossRef]
- Rockström, J.; Steffen, W.; Noone, K.; Persson, Å.; Chapin, F.S.; Lambin, E.F.; Lenton, T.M.; Scheffer, M.; Folke, C.; Schellnhuber, H.J.; et al. Safe Operating Space for Humanity. Nature 2009, 461, 472–475. [Google Scholar] [CrossRef] [PubMed]
- Niu, Y.; Zhu, H.; Yang, S.; Ma, S.; Zhou, J.; Chu, B.; Hua, R.; Hua, L. Overgrazing Leads to Soil Cracking That Later Triggers the Severe Degradation of Alpine Meadows on the Tibetan Plateau. Land Degrad. Dev. 2019, 30, 1243–1257. [Google Scholar] [CrossRef]
- Han, Q.; Luo, G.; Li, C.; Xu, W. Modeling the Grazing Effect on Dry Grassland Carbon Cycling with Biome-BGC Model. Ecol. Complex. 2014, 17, 149–157. [Google Scholar] [CrossRef]
- Wang, C.S.; Meng, F.D.; Li, X.E.; Jiang, L.L.; Wang, S.P. Responses of Alpine Grassland Ecosystem on Tibetan Plateau to Climate Change: A Mini Review. Chin. J. Ecol. 2013, 32, 1587–1595. [Google Scholar]
- Yao, T.; Wu, F.; Ding, L.; Sun, J.; Zhu, L.; Piao, S.; Deng, T.; Ni, X.; Zheng, H.; Ouyang, H. Multispherical Interactions and Their Effects on the Tibetan Plateau’s Earth System: A Review of the Recent Researches. Natl. Sci. Rev. 2015, 2, 468–488. [Google Scholar] [CrossRef] [Green Version]
- Chen, H.; Zhu, Q.; Peng, C.; Wu, N.; Wang, Y.; Fang, X.; Gao, Y.; Zhu, D.; Yang, G.; Tian, J.; et al. The Impacts of Climate Change and Human Activities on Biogeochemical Cycles on the Qinghai-Tibetan Plateau. Glob. Chang. Biol. 2013, 19, 2940–2955. [Google Scholar] [CrossRef]
- Fan, J.; Yong, X.U.; Wang, C.S.; Niu, Y.F.; Chen, D.; Sun, W. The Effects of Human Activities on the Ecological Environment of Tibet Over the Past Half Century. Chin. Sci. Bull. 2015, 60, 3057–3066. [Google Scholar] [CrossRef] [Green Version]
- Dong, S.K.; Li, J.P.; Li, X.Y.; Wen, L.; Zhu, L.; Li, Y.Y.; Ma, Y.S.; Shi, J.J.; Dong, Q.M.; Wang, Y.L. Application of Design Theory for Restoring the “Black Beach” Degraded Rangeland at the Headwater Areas of the Qinghai-Tibetan Plateau. Afr. J. Agric. Res. 2010, 5, 3542–3552. [Google Scholar]
- Chen, B.; Zhang, X.; Tao, J.; Wu, J.; Wang, J.; Shi, P.; Zhang, Y.; Yu, C. The Impact of Climate Change and Anthropogenic Activities on Alpine Grassland Over the Qinghai-Tibet Plateau. Agric. For. Meteorol. 2014, 189, 11–18. [Google Scholar] [CrossRef]
- Lehnert, L.W.; Wesche, K.; Trachte, K.; Reudenbach, C.; Bendix, J. Climate Variability Rather Than Overstocking Causes Recent Large Scale Cover Changes of Tibetan Pastures. Sci. Rep. 2016, 6, 24367. [Google Scholar] [CrossRef] [Green Version]
- Yang, Y.H.; Fang, J.Y.; Fay, P.A.; Bell, J.E.; Ji, C.J. Rain Use Efficiency Across a Precipitation Gradient on the Tibetan Plateau. Geophys. Res. Lett. 2010, 37. [Google Scholar] [CrossRef]
- Zhao, G.; Liu, M.; Shi, P.; Zong, N.; Wang, J.; Wu, J.; Zhang, X. Spatial–Temporal Variation of ANPP and Rain-Use Efficiency Along a Precipitation Gradient on Changtang Plateau, Tibet. Remote Sens. 2019, 11, 325. [Google Scholar] [CrossRef] [Green Version]
- Sun, H.; Zheng, D.; Yao, T.; Zhang, Y. Protection and Construction of the National Ecological Security Shelter Zone on Tibetan Plateau. Acta Geogr. Sin. 2012, 67, 3–12. [Google Scholar]
- Li, M.; Wu, J.S.; Feng, Y.F.; Niu, B.; He, Y.T.; Zhang, X.Z. Climate Variability Rather Than Livestock Grazing Dominates Changes in Alpine Grassland Productivity Across Tibet. Front. Ecol. Evol. 2021, 9. [Google Scholar] [CrossRef]
- Long, R.J.; Apori, S.O.; Castro, F.B.; Orskov, E.R. Feed Value of Native Forages of the Tibetan Plateau of China. Anim. Feed Sci. Tech. 1999, 80, 101–113. [Google Scholar] [CrossRef]
- Mirjanka, L.; Brankica, M. Albers Conical Equal-Area Projection. Geod. List 1996, 2, 161–170. [Google Scholar]
- Jonsson, P.; Eklundh, L. TIMESAT-A Program for Analyzing Time-Series of Satellite Sensor Data. Comput. Geosci.-UK 2004, 30, 833–845. [Google Scholar] [CrossRef] [Green Version]
- Eklundh, L.; Jönsson, P. TIMESAT: A Software Package for Time-Series Processing and Assessment of Vegetation Dynamics. In Remote Sensing Time Series; Springer: Cham, Switzerland, 2015. [Google Scholar]
- Luo, J.; Ying, K.; Bai, J. Savitzky–Golay Smoothing and Differentiation Filter for Even Number Data. Signal. Process. 2005, 85, 1429–1434. [Google Scholar] [CrossRef]
- Allan, R.; Pereira, L.; Smith, M. Crop. Evapotranspiration-Guidelines for Computing Crop Water Requirements; FAO: Rome, Italy, 1998. [Google Scholar]
- Hutchinson, M. Anusplin Version 4.3. Centre for Resource and Environmental Studies; Australian National University: Canberra, Australia, 2004. [Google Scholar]
- Cao, Y.; Wu, J.; Zhang, X.; Niu, B.; He, Y. Comparison of Methods for Evaluating the Forage-Livestock Balance of Alpine Grasslands on the Northern Tibetan Plateau. J. Resour. Ecol. 2020, 11, 272–282. [Google Scholar]
- Monteith, J.L.; Moss, C.J.; Cooke, G.W.; Pirie, N.W.; Bell, G.D.H. Climate and the Efficiency of Crop Production in Britain. Philos. Trans. R. Soc. London B Biol. Sci. 1977, 281, 277–294. [Google Scholar]
- Potter, C.S.; Randerson, J.T.; Field, C.B.; Matson, P.A.; Vitousek, P.M.; Mooney, H.A.; Klooster, S.A. Terrestrial Ecosystem Production: A Process Model Based on Global Satellite and Surface Data. Glob. Biogeochem. Cycles 1993, 7, 811–841. [Google Scholar] [CrossRef]
- Potter, C. Predicting Climate Change Effects on Vegetation, Soil Thermal Dynamics, and Carbon Cycling in Ecosystems of Interior Alaska. Ecol. Model. 2004, 175, 1–24. [Google Scholar] [CrossRef]
- Piao, S.; Fang, J.; He, J. Variations in Vegetation Net Primary Production in the Qinghai-Xizang Plateau, China, from 1982 to 1999. Clim. Chang. 2006, 74, 253–267. [Google Scholar] [CrossRef]
- Yuan, J.; Niu, Z.; Wang, C. Vegetation NPP Distribution Based on MODIS Data and CASA Model-A Case Study of Northern Hebei Province. Chin. Geogr. Sci. 2006, 16, 334–341. [Google Scholar] [CrossRef]
- Field, C.B.; Randerson, J.T.; Malmström, C.M. Global Net Primary Production: Combining Ecology and Remote Sensing. Remote Sens. Environ. 1995, 51, 74–88. [Google Scholar] [CrossRef] [Green Version]
- Field, C.B.; Behrenfeld, M.J.; Randerson, J.T.; Falkowski, P. Primary Production of the Biosphere: Integrating Terrestrial and Oceanic Components. Science 1998, 281, 237–240. [Google Scholar] [CrossRef] [PubMed] [Green Version]
- Wang, H.; Jia, G.; Fu, C.; Feng, J.; Zhao, T.; Ma, Z. Deriving Maximal Light Use Efficiency From Coordinated Flux Measurements and Satellite Data for Regional Gross Primary Pro-Duction Modeling. Remote Sens. Environ. 2010, 114, 2248–2258. [Google Scholar] [CrossRef]
- Zhang, Y.; Qi, W.; Zhou, C.; Ding, M.; Liu, L.; Gao, J.; Bai, W.; Wang, Z.; Zheng, D. Spatial and Temporal Variability in the Net Primary Production of Alpine Grassland on the Tibetan Plateau Since 1982. J. Geogr. Sci. 2014, 24, 269–287. [Google Scholar] [CrossRef]
- Li, M.; Zhang, X.; Wu, J.; Ding, Q.; He, Y. Declining Human Activity Intensity on Alpine Grasslands of the Tibetan Plateau. J. Environ. Manag. 2021, 296, 113198. [Google Scholar] [CrossRef]
- Bai, Y.; Wu, J.; Xing, Q.; Pan, Q.; Huang, J.; Yang, D.; Han, X. Primary Production and Rain Use Efficiency Across a Precipitation Gradient on the Mongolia Plateau. Ecology 2008, 89, 2140–2153. [Google Scholar] [CrossRef]
- Zhang, L.X.; Fan, J.W.; Shao, Q.Q.; Tang, F.P.; Zhang, H.Y.; Yu-Zhe, L.I. Changes in Grassland Yield and Grazing Pressure in the Three Rivers Headwater Region Before and After the Implementation of the Eco-Restoration Project. Acta Pratacult. Sin. 2014, 23, 116–123. [Google Scholar]
- Liu, S.; Cheng, F.; Dong, S.; Zhao, H.; Hou, X.; Wu, X. Spatiotemporal Dynamics of Grassland Aboveground Biomass on the Qinghai-Tibet Plateau Based on Validated MODIS NDVI. Sci. Rep. 2017, 7, 4182. [Google Scholar] [CrossRef] [Green Version]
- Zhao, J.; Hartmann, H.; Trumbore, S.; Ziegler, W.; Zhang, Y. High Temperature Causes Negative Whole-Plant Carbon Balance under Mild Drought. New Phytol. 2013, 200, 330–339. [Google Scholar] [CrossRef]
- Hudson, J.; Henry, G.; Cornwell, W.K. Taller and Larger: Shifts in Arctic Tundra Leaf Traits After 16 Years of Experimental Warming. Glob. Chang. Biol. 2011, 17, 1013–1021. [Google Scholar] [CrossRef]
- Qun, G.; Zhongmin, H.; Shenggong, L.; Guirui, Y.; Xiaomin, S.; Leiming, Z.; Songlin, M.; Xianjin, Z.; Yanfen, W.; Yingnian, L.; et al. Contrasting Responses of Gross Primary Productivity to Precipitation Events in a Water-Limited and a Temperature-Limited Grassland Ecosystem. Agric. For. Meteorol. 2015, 214, 169–177. [Google Scholar]
- Fu, G.; Shen, Z.X.; Zhang, X.Z. Increased Precipitation Has Stronger Effects on Plant Production of an Alpine Meadow Than Does Experimental Warming in the Northern Tibetan Plateau. Agric. For. Meteorol. 2018, 249, 11–21. [Google Scholar] [CrossRef]
- Zhang, Q.; Li, M.A.; Zhang, Z.; Wenhua, X.U.; Zhou, B.; Song, M.; Qiao, A.; Wang, F.; She, Y.; Yang, X. Ecological Restoration of Degraded Grassland in Qinghai-Tibet Alpine Region: Degradation Status, Restoration Measures, Effects and Prospects. Acta Ecol. Sin. 2019, 39, 7441–7451. [Google Scholar]
- Zhang, Y.; Pan, Y.; Zhang, X.; Wu, J.; Yu, C.; Li, M.; Wu, J. Patterns and Dynamics of the Human Appropriation of Net Primary Production and Its Components in Tibet. J. Environ. Manag. 2018, 210, 280–289. [Google Scholar] [CrossRef]
- Li, S.; Wu, J.; Jian, G.; Li, S. Human Footprint in Tibet: Assessing the Spatial Layout and Effectiveness of Nature Reserves. Sci. Total Environ. 2018, 621, 18–29. [Google Scholar] [CrossRef]
- Li, L.; Zhang, Y.; Liu, L.; Wu, J.; Wang, Z.; Li, S.; Zhang, H.; Zu, J.; Ding, M.; Paudel, B. Spatiotemporal Patterns of Vegetation Greenness Change and Associated Climatic and Anthropogenic Drivers on the Tibetan Plateau during 2000–2015. Remote Sens. 2018, 10, 1525. [Google Scholar] [CrossRef] [Green Version]
- Huang, K.; Zhang, Y.; Zhu, J.; Liu, Y.; Zu, J.; Zhang, J. The Influences of Climate Change and Human Activities on Vegetation Dynamics in the Qinghai-Tibet Plateau. Remote Sens. 2016, 8, 876. [Google Scholar] [CrossRef] [Green Version]
- Molnar, P.; Boos, W.; Battisti, D. Orographic Controls on Climate and Paleoclimate of Asia: Thermal and Mechanical Roles for the Tibetan Plateau. Annu. Rev. Earth Planet. Sci. 2010, 38, 77–102. [Google Scholar] [CrossRef] [Green Version]
- Xu, X.; Chen, H.; Levy, J.K. Spatiotemporal Vegetation Cover Variations in the Qinghai-Tibet Plateau under Global Climate Change. Chin. Sci. Bull. 2008, 53, 915–922. [Google Scholar] [CrossRef] [Green Version]
- Le Houérou, H.N.; Bingham, R.L.; Skerbek, W. Relationship Between the Variability of Primary Production and the Variability of Annual Precipitation in World Arid Lands. J. Arid Environ. 1988, 15, 1–18. [Google Scholar] [CrossRef]
- Paruelo, J.M.; Lauenroth, W.K.; Burke, I.C.; Sala, O.E. Grassland Precipitation-Use Efficiency Varies Across a Resource Gradient. Ecosystems 1999, 2, 64–68. [Google Scholar] [CrossRef]
- Epstein, H.E.; Lauenroth, W.K.; Burke, I.C. Effects of Temperature and Soil Texture on ANPP in the U.S. Great Plants. Ecology 1997, 78, 2628–2631. [Google Scholar] [CrossRef]
- Jobbágy, E.; Sala, O. Controls of Grass and Shrub Aboveground Production in the Patagonian Steppe. Ecol. Appl. 2000, 10, 541–549. [Google Scholar] [CrossRef]
- Wei, H.; Wu, B.; Yang, W.; Luo, T. Low Rainfall-Induced Shift in Leaf Trait Relationship within Species Along a Semi-Arid Sandy Land Transect in Northern China. Plant Biol. 2011, 13, 85–92. [Google Scholar] [CrossRef]
- Liu, Z.; Huang, M. Assessing Spatio-Temporal Variations of Precipitation-Use Efficiency Over Tibetan Grasslands Using MODIS and In-Situ Obser-Vations. Front. Earth Sci. 2016, 10, 784–793. [Google Scholar] [CrossRef]
- Shi, S.B. The Photosynthesis of Plant Community in Kobresia humilis Meadow. Chin. J. Plant Ecol. 1996, 20, 225–234. [Google Scholar]
- Knapp, A.K.; Smith, M.D. Variation Among Biomes in Temporal Dynamics of Aboveground Primary Production. Science 2001, 291, 481–484. [Google Scholar] [CrossRef] [Green Version]
- Ogaya, R.; Peuelas, J. Comparative Field Study of Quercus ilex and Phillyrea latifolia: Photosynthetic Response to Experimental Drought Conditions. Environ. Exp. Bot. 2003, 50, 137–148. [Google Scholar] [CrossRef]
- Wu, J.; Zhang, X.; Shen, Z.; Shi, P.; Xu, X.; Li, X. Grazing-Exclusion Effects on Aboveground Biomass and Water-Use Efficiency of Alpine Grasslands on the Northern Tibetan Plateau. Rangeland Ecol. Manag. 2013, 66, 454–461. [Google Scholar] [CrossRef]
- Mikola, J.; Setälä, H.; Virkajärvi, P.; Saarijärvi, K.; Ilmarinen, K.; Voigt, W.; Vestberg, M. Defoliation and Patchy Nutrient Return Drive Grazing Effects on Plant and Soil Properties in a Dairy Cow Pasture. Ecol. Monogr. 2009, 79, 221–244. [Google Scholar] [CrossRef] [Green Version]
- Mazancourt, C.D.; Loreau, M.; Abbadie, L. Grazing Optimization and Nutrient Cycling: When Do Herbivores Enhance Plant Production? Ecology 1998, 79, 2242–2252. [Google Scholar] [CrossRef]
- Luo, G.; Han, Q.; Zhou, D.; Li, L.; Xi, C.; Yan, L.; Hu, Y.; Li, B.L. Moderate Grazing Can Promote Aboveground Primary Production of Grassland under Water Stress. Ecol. Complex. 2012, 11, 126–136. [Google Scholar] [CrossRef]
Mean of NPP (g C m−2) | Trend of NPP (%) | ||||
---|---|---|---|---|---|
Significant Increasing | Insignificant Increasing | Significant Decreasing | Insignificant Decreasing | ||
AM | 133.6 ± 81.5 a | 24.63 | 60.59 | 0.60 | 14.17 |
AS | 50.7 ± 50.76 b | 36.43 | 51.57 | 0.79 | 11.21 |
DS | 45.1 ± 46.2 c | 45.36 | 50.03 | 0.21 | 4.40 |
total | 88.5 ± 78.4 | 31.34 | 55.65 | 0.68 | 12.33 |
Mean of PUE (g C m−2 mm−1) | Trend of PUE (%) | ||||
---|---|---|---|---|---|
Significant Increasing | Insignificant Increasing | Significant Decreasing | Insignificant Decreasing | ||
AM | 0.31 ± 0.15 a | 2.55 | 55.33 | 2.50 | 39.62 |
AS | 0.19 ± 0.14 b | 3.36 | 53.35 | 0.86 | 42.43 |
DS | 0.32 ± 0.15 a | 2.32 | 25.80 | 0.38 | 71.51 |
total | 0.25 ± 0.17 | 2.96 | 53.31 | 1.59 | 42.15 |
QTP | AM | AS | DS | |
---|---|---|---|---|
CMAT_NPP | 17.5 ± 0.01 | 16.7 ± 0.02 | 18.3 ± 0.02 | 16.3 ± 0.07 |
CMAP_NPP | 14.8 ± 0.01 | 10.3 ± 0.02 | 18.5 ± 0.02 | 20.8 ± 0.07 |
CGI_NPP | 5.5 ± 0.01 | 5.7 ± 0.01 | 5.1 ± 0.01 | 6.8 ± 0.04 |
QTP | AM | AS | DS | |
---|---|---|---|---|
CMAT_PUE | 9.6 ± 0.01 | 13.3 ± 0.02 | 6.6 ± 0.01 | 9.6 ± 0.05 |
CMAP_PUE | 52.7 ± 0.02 | 45.1 ± 0.03 | 59.8 ± 0.03 | 56.4 ± 0.11 |
CGI_PUE | 3.1 ± 0.01 | 3.5 ± 0.01 | 3.0 ± 0.01 | 2.7 ± 0.03 |
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. |
© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Share and Cite
Yu, H.; Ding, Q.; Meng, B.; Lv, Y.; Liu, C.; Zhang, X.; Sun, Y.; Li, M.; Yi, S. The Relative Contributions of Climate and Grazing on the Dynamics of Grassland NPP and PUE on the Qinghai-Tibet Plateau. Remote Sens. 2021, 13, 3424. https://doi.org/10.3390/rs13173424
Yu H, Ding Q, Meng B, Lv Y, Liu C, Zhang X, Sun Y, Li M, Yi S. The Relative Contributions of Climate and Grazing on the Dynamics of Grassland NPP and PUE on the Qinghai-Tibet Plateau. Remote Sensing. 2021; 13(17):3424. https://doi.org/10.3390/rs13173424
Chicago/Turabian StyleYu, Huilin, Qiannan Ding, Baoping Meng, Yanyan Lv, Chang Liu, Xinyu Zhang, Yi Sun, Meng Li, and Shuhua Yi. 2021. "The Relative Contributions of Climate and Grazing on the Dynamics of Grassland NPP and PUE on the Qinghai-Tibet Plateau" Remote Sensing 13, no. 17: 3424. https://doi.org/10.3390/rs13173424