Change in Net Primary Productivity of Parcel Land in Logan and Breckinridge Counties in Central Kentucky using MODIS dataset.

1. Change in Net Primary Productivity of Parcel Land in Logan
and Breckinridge Counties Central Kentucky
Bijesh Mishra, Buddhi Gyawali,
Kentucky State University, 400 East Main St, Frankfort, KY 40601
INTRODUCTION
Net primary productivity (NPP) is the accumulation of organic matter in the plant per unit
time per unit area. NPP serve as an important indicator of vegetative activities as well as the
balance of carbon in the ecosystem (Bian, 2010; Yang, 2017). NPP has been used as an
important indicator of forest cover, function and health. The losses in NPP shows very adverse
negative impact in the ecosystem, environment, fresh water, biodiversity (Yang, 2017). NPP
Change is the key to evaluate heath condition of ecosystem. Use of remote sensing
technologies to monitor the annual change of NPP is beneficial to evaluate the heath
condition of ecosystem (Bian, 2010).
With the increase in the global demand of food, agriculture is becoming intensive, resource-
intensive and less sustainable (Robinson et al., 2014). To meet the Sustainable Development
Goals, agriculture sector needs a universal and informative indices to measure agriculture
sustainability (HarvestChoice, 2014). However heterogeneity of crops and enterprise in
agriculture sector makes more difficult to measure the productivity and the sustainability. The
understanding of productivity of agriculture land is important not only from the perspective
of yield per unit area but also from the perspective of total biomass production and carbon
accumulation. NPP is taken as an important and sensitive indicator of forest productivity and
is intensively used in forestry sector (Yang, 2017). Since NPP is based on the photosynthetic
activities of plants and crops, it can be used in the agriculture sector uniformly despite the
heterogeneous nature of agriculture enterprises as an indicator of productivity and
accumulation of organic matter.
OBJECTIVES
• To study average NPP and trend in different farm size.
• To study the Annual NPP Change in different sized farm in Breckinridge and Logan Counties.
METHODS
RESULTS
CONCLUSION
This study shows possibility of using NPP as an indicator of farm productivity. However, it should
be further studied along with other agriculture productivity indictors to use as a dependable
proxy of farm productivity.
This study is a preliminary study. However, it can be an important baseline to further develop
this research to understand use of NPP as proxy of farm productivity. The importance of this
research is increased by the fact that not many researchers has considered NPP as a proxy of
farm productivity.
The annual change in NPP is not consistent. The change differs by year and the location. The
wavy nature of NPP makes it more predictable if long term trend is studied. So, NPP cycle of
certain location can be understood by studying long run trend of NPP.
REFERENCES
Bian, J., Li, A., & Deng, W. (2010). Estimation and analysis of net primary Productivity of Ruoergai wetland in China for the recent 10 years based on remote sensing. Procedia Environmental Sciences,2, 288-301.
doi:10.1016/j.proenv.2010.10.035
HarvestChoice. (2014). Net Primary Productivity and Sustainable Intensification: An Exploratory Exercise. Retrieved April 02, 2018, from http://harvestchoice.org/node/9650
Robinson, N., Koo, J., Cox, C., & Guo, Z. (2014). Monitoring Agricultural Sustainability Using Remotely Sensed Net Primary Production Over Time and Space. Retrieved April 02, 2018, from
https://harvestchoice.org/sites/default/files/Robinson_IFPRI_POSTER.pdf
Yang, J., Zhang, X., Luo, Z., & Yu, X. (2017). Nonlinear Variations of Net Primary Productivity and Its Relationship with Climate and Vegetation Phenology, China. Forests,8(10), 361. doi:10.3390/f8100361
ACKNOWLEDGEMENT
This research was funded by USDA/NIFA Evans Allen Fund for Developing Decision Support Systems (DSS) for Agroecosystems Management and Sustainability. The authors
would like to thank Aman Bhatta for his help.
Table 1: Average NPP (KgCM-2Yr-1) and Standard Deviation of Mean according to farm categories in Breckinridge
and Logan Counties.
Data Used: MYD17A3H Version 6 moderate resolution imaging spectroradiometer (MODIS)
annual PRNL DAAC Net Primary Productivity at 500 Meter pixel resolution data (2002 to
2014) downloaded from https://modis.ornl.gov/data.html and parcel data of Breckinridge
and Logan Counties, KY.
Farm parcel was separated from the parcel data of respective counties. All farms below 65
acres were removed to obtain final farm parcel information for further analysis. This was
done to match parcel size with the NPP pixel size. The farms were categorized into three
categories: Small farms (65 to 100 Acres), Medium Farms (100 to 200 Acres) and Large
Farms (Above 200 Acres).
Zonal Statistics and raster calculator were used to calculate average NPP and change in NPP
from 2002 to 2014. Change in NPP = [NPP(t)-NPP(t-1)]/[t-(t-1)], where t = Year (2002 to 2014)
for each parcel.
Figure 1: Area of Study: Parcel Map of Breckinridge and Logan Counties and Their Locations in Kentucky
Year
Breckinridge County Logan County
Small Farm Medium Farms Large Farms Small Farm Medium Farms Large Farms
Mean St. Dev. Mean St. Dev. Mean St. Dev. Mean St. Dev. Mean St. Dev. Mean St. Dev.
2002 2672.145 1068.244 2674.050 943.405 2991.881 954.119 3070.520 1041.330 3159.424 928.591 2818.131 876.204
2003 17884.693 2067.050 17867.803 1732.233 19035.464 1340.156 17884.693 1765.406 17867.803 1653.374 17730.411 1688.416
2004 6694.623 572.274 6654.637 519.099 6686.525 611.372 6647.734 524.353 6647.572 462.164 6552.340 522.847
2005 5892.157 649.191 5855.437 585.627 6186.169 623.952 6166.658 601.350 6180.452 517.431 5796.448 448.398
2006 5148.491 620.613 5110.720 550.833 5462.541 580.494 5458.455 571.517 5500.907 506.397 4984.141 464.751
2007 4392.728 968.897 4399.846 908.973 4058.738 900.028 4232.520 728.737 4235.047 618.973 4211.556 571.883
2008 6088.522 563.455 6046.910 542.860 6700.835 622.118 6653.718 504.942 6648.768 435.295 5959.330 448.716
2009 6526.430 667.499 6469.819 615.281 6795.685 691.464 6740.772 633.514 6733.789 552.997 6453.820 631.928
2010 5212.462 504.969 5158.675 461.209 5439.416 542.951 5431.914 548.840 5421.835 474.686 5081.962 365.688
2011 5587.233 655.051 5534.658 583.375 5755.203 626.546 5739.130 554.424 5744.353 474.049 5455.769 413.289
2012 7590.268 693.270 7553.164 610.230 7034.467 605.830 7055.586 657.995 7082.465 581.550 7461.985 459.559
2013 6706.925 748.357 6652.766 717.293 6816.502 794.135 6741.290 581.183 6743.168 509.600 6658.071 558.471
2014 6213.658 675.413 6135.276 648.884 6500.646 740.260 6453.951 573.174 6437.967 537.166 6149.488 592.012
0.000
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2002 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014
NPP(KgCM-2Yr-1)
Year
Breckinridge County NPP Mean Acording to Farm Size
Small Farm Medium Farms Large Farms
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2002 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014
NPP(KgCM-2Yr-1)
Year
Logan County Average NPP According to Farm Size
Small Farm Medium Farms Large Farms
Figure 3: Average NPP (KgCM-2Yr-1) of Breckinridge (left) and Logan (right) Counties Based on Farm Categories.
• Above table and graphs show average NPP categorized in three different types of farms size
in two different counties of Kentucky. The trend over 13 years time period in three different
farm size shows that the trend of NPP does not change based on farm size or location. So, it
can be a good and stable indicator of farm productivity in all types and size of farm as well as
locations.
• Maps in the middle section of this poster are annual change in NPP from 2002 to 2014 for
two counties, Breckinridge and Logan, of Kentucky. Since the calculation is unidirectional
[NPP(t)-NPP(t-1)]/[t-(t-1)], the value can be positive or negative, which is also represented in
the imageries, due to non-linear wavy nature of NPP.
Logan County
Figure 2 (maps in the middle): Annual change in NPP from 2002 top 2014. The NPP was calculated
for every successive [t-(t-1)] years from 2002 to 2014 for both counties and arranged in
descending order of the year for Breckinridge and Logan Counties respectively in this poster.