Plants play an essential role in matter and energy transformations and are key messengers in the carbon and energy cycle. Net primary productivity (NPP) reflects the capability of plants to transform solar energy into photosynthesis. It is very sensible for factors affecting on vegetation variability such as climate, soils, plant characteristics and human activities. So, it can be used as an indicator of actual and potential trend of vegetation. In this study we used the actual NPP which was derived from MODIS to assess the response of NPP to climate variables in Gadarif State, from 2000 to 2010. The correlations between NPP and climate variables (temperature and precipitation) are calculated using Pearson’s Correlation Coefficientand ordinary least squares regression. The main results show the following 1) the correlation Coefficient between NPP and mean annual temperature is Somewhat negative for Feshaga, Rahd, Gadarif and Galabat areas and weakly negative in Faw area; 2) the correlation Coefficient between NPP and annual total precipitation is weakly negative in Faw, Rahd and Galabat areas and somewhat negative in Galabat and Rahd areas. This study demonstrated that the correlation analysis between NPP and climate variables (precipitation and temperature) gives reliably result of NPP responses to climate variables that is clearly in a very large scale of study area.
References
[1]
Goudriaan, J. (1995) Global Carbon Cycle and Carbon Sequestration. In: Beran, M.A., Eds., Carbon Sequestration in the Biosphere, Springer-Verlag, Berlin, 3-18. https://doi.org/10.1007/978-3-642-79943-3_1
[2]
Chen, C., Park, T., Wang, X.H., Piao, S.L., Xu, B.D., Chaturvedi, R.K., Fuchs, R., Brovkin, V., Ciais, P., Fensholt, R., Tømmervik, H., Bala, G., Zhu, C.C., Nemani, R.R. and Myneni, R.B. (2019) China and India Lead in Greening of the World through Land-Use Management. Nature Sustainability, 2, 122-129. https://doi.org/10.1038/s41893-019-0220-7
[3]
Liu, G., Sun, R., Xiao, Z.Q. and Cui, T.X. (2017) Analysis of Spatial and Temporal Variation of Net Primary Productivity and Climate Controls in China from 2001 to 2014. Acta Ecologica Sinica, 37, 4936-4945.
[4]
Govindasamy, B., Jaideep, J., Rajiv, K., Chaturvedi Hosahalli, V., Gangamani Hirofumi, H. and Rama, N. (2013) Trends and Variability of AVHRR-Derived NPP in India. Remote Sensing,5, 810-829. https://doi.org/10.3390/rs5020810
[5]
Patel, N.R., Bhattacharjee, B., Mohammed, A.J., Priya, T. and Saha, S.K. (2006) Remote Sensing of Regional Yield Assessment of Wheat in Haryana, India. International Journal of Remote Sensing, 27, 4071-4090. https://doi.org/10.1080/01431160500377188
[6]
Fan, J., Shao, Q. and Liu, J. (2010) Assessment of Effects of Climate Change and Grazing Activity on Grassland Yield in the Three Rivers Headwaters Region of Qingha-Tibet Plateau, China. Environmental Monitoring and Assessment, 170, 571-584. https://doi.org/10.1007/s10661-009-1258-1
[7]
Amiro, B.D., Chen, J.M., and Liu, J. (2000) Net Primary Productivity Following Forest Fire for Canadian Ecoregions. Canadian Journal of Forest Research, 30, 939-947. https://doi.org/10.1139/x00-025
[8]
Milner, K.S., Running, S.W. and Coble, D.W. (1996) Biophysical Soil-Site Model for Estimating Potential Productivity of Forested Landscapes. Canadian Journal of Forest Resources, 26, 1174-1186. https://doi.org/10.1139/x26-131
[9]
Nemani, R.R., Charles, D., Hashimoto, K.H., Jolly, W.M., Piper, S.C. and Tucker, C.J. (2003) Climate-Driven Increases in Global Terrestrial Net Primary Production from 1982 to 1999. Science, 300, 1560-1563. https://doi.org/10.1126/science.1082750
[10]
Wessels K.J., Prince S.D., Malherbe J., Small J., Frost P.E. and Van Zyl, D. (2007) Can Human Induced Land Desertification Be Distinguished from the Effects of Rainfall Variability? A Case Study in South Africa. Journal of Arid Environments, 68, 271-297. https://doi.org/10.1016/j.jaridenv.2006.05.015
[11]
Prince, S.D. and Goward, S.N. (1995) Global Primary Production: A Remote Sensing Approach. Journal of Biogeography, 22, 815-835. https://doi.org/10.2307/2845983
[12]
Knapp, A.K. and Smith, M.D. (2001) Variation among Biomes in Temporal Dynamics of Aboveground Primary Production. Science, 291, 481-484. https://doi.org/10.1126/science.291.5503.481
[13]
Elhag, M. (2006) Causes and Impact of Desertification in the Butana Area of Sudan. Ph.D. Thesis, University of the Free State, Bloemfontein.
[14]
Aguilar, E., Barry, A.A., Brunet, M., Ekang, L., Fernandes, A., Massoukina, M., Mbah, J., Mhanda, A., Nascimento, D.J., Peterson, T.C., Umba, O.T., Tomou, M., and Zhang, X. (2009) Changes in Temperature and Precipitation Extremes in Western Central Africa, Guinea Conakry, and Zimbabwe, 1955-2006. Journal of Geophysical Research, 114, D02115. https://doi.org/10.1029/2008JD011010
[15]
Choi, G., Collins, D., Ren, G., Trewin, B., Baldi, M., Fukuda, Y., Afzaal, M., Pianmana, T., Gomboluudev, P., Huong, P.T.T., Lias, N., Kwon, W.T., Boo, K.O., Cha, Y.M. and Zhou, Y. (2009) Changes in Means and Extreme Events of Temperature and Precipitation in the Asia Pacific Network Region, 1955-2007. International Journal of Climatology, 29, 1906-1925. https://doi.org/10.1002/joc.1979
[16]
Rehman, S. (2010) Temperature and Rainfall Variation over Dhahran, Saudi Arabia (1970-2006). International Journal of Climatology, 30, 445-449. https://doi.org/10.1002/joc.1907
[17]
Yagoub, Y.E., Li, Z.Q., Musa, O.S., Anjum, M.N., Wang, F.T. and Zhang, B. (2017) Investigation of Climate and Land Use Policy Change Impacts on Food Security in Eastern Sudan, Gadarif State.Journal of Geographic Information System, 9, 546-557. https://doi.org/10.4236/jgis.2017.95034
[18]
Sulieman, H.M. and Elagib, N.A. (2012) Implications of Climate, Land-Use and Land-Cover Changes for Pastoralism in Eastern Sudan. Journal of Arid Environments, 85, 132-141. https://doi.org/10.1016/j.jaridenv.2012.05.001
[19]
Elagib, N.A. and Elhaj, M.M. (2011) Major Climate Indicators of Ongoing Drought in Sudan. Journal of Hydrology, 409, 612-625. https://doi.org/10.1016/j.jhydrol.2011.08.047
[20]
Idreas, A.E.A. and Abdo Desougi, M. (2015) Potential Impact of Rain Fed Mechanized Farming and Shelter Belts Establishment on the Environment, Case Study Ghadambaliya, Gedaref, Sudan. Journal of Natural Resources and Environmental Studies, 33, 36-43.
[21]
Zheng, Y.R., Xie, Z.X., Robert, C., et al. (2006) Did Climate Drive Ecosystem Change and Induce Desertification in Otindag Sandy Land, China over the Past 40 Years? Journal of Arid Environments, 64, 523-541. https://doi.org/10.1016/j.jaridenv.2005.06.007
[22]
Zhang, C.X., Wang, X.M. and Li, J.C. (2011) Roles of Climate Changes and Human Interventions in Land Degradation: A Case Study by Net Primary Productivity Analysis in China’s Shiyanghe Basin. Environmental Earth Sciences, 64, 2183-2193. https://doi.org/10.1007/s12665-011-1046-4
[23]
Zika, M. and Erb, K. (2009) The Global Loss of Net Primary Production Resulting from Human-Induced Soil Degradation in Dry Lands. Ecological Economics, 69, 310-318. https://doi.org/10.1016/j.ecolecon.2009.06.014
[24]
Jahelnabi, A.E., Zhao, J., Li, C., Fadoul, S.M., Shi, Y., Bsheer, A.K. and Yagoub, Y.E. (2016) Assessment of the Contribution of Climate Change and Human Activities to Desertification in Northern Kordufan-Province, Sudan Using Net Primary Productivity as an Indicator. Contemporary Problems of Ecology, 9, 674-683. https://doi.org/10.1134/S1995425516060068
[25]
Foley, J.A., Levis, S., Costa, M.H., Cramer, W. and Pollard, D. (2000) Incorporating Dynamic Vegetation Cover within Global Climate Models. Ecological Applications, 10, 1620-1632. https://doi.org/10.1890/1051-0761(2000)010[1620:IDVCWG]2.0.CO;2
