crop rotation as a factor of crop failure in drought period
TRANSCRIPT
Crop rotation as a factor of crop failure in drought period
Savin I., Kyrianova E., Medvedeva M.
V.V. Dokuchaev Soil Science Institute, Moscow
Space Research Institute of Russian Academy of Sciences, Moscow
K.A. Timiriazev Agricultural Academy, Moscow
Agricultural vegetation affected by drought
• crop stress and yield reduction • drying of part of leaves and strong yield reduction • drying of all leaves and total crop yield lost
Percent of crops affected by drought in 2010
Potential Factors of Crop Damage During Drought
Extreme air temperature
Insufficient amount of water in soil:
low precipitation
dry soil
soil properties (texture, humidity, ground water table…)
specific of land use (crop-predecessor)
Total amount of moisture in loamy soil before sowing as depended from crop-predecessor
Test Region
NDVI behavior
Long-term average seasonal maximum value
Long-term average seasonal maximum
Current seasonal maximum value
Intermediate minimum
Long-term average seasonal minimum
Date of current season maximum
NDVI time profiles smoothing
6000
6500
7000
7500
8000
8500
9000
9500
17 22 27 32
Время, недели года
ND
VI*
10000
Исходный ряд Сглаженный ряд
Year - analogue
5000
5500
6000
6500
7000
7500
8000
8500
9000
9500
10000
1 5 9 13 17 21 25 29 33 37 41 45 49
Время, недели
ND
VI*
10000
2001 год
2002 год
2003 год
2004 год
2005 год
аналог2006 год
2007 год
2008 год
2009 год
2010 год
Max
Min
Date of seasonal maximum >= 3 weeks difference
Crop affected by drought in 2010 in Chuvashia
Crops affected by drought in 2010 in Komsomolsky district
Crop was lost on 11 200 ha according regional statistics (11 100 according analysis of MODIS data)
NDVI and Crop Type
Winter cereals
Spring cereals soya
Summer crops
Perennial grasses Annual grasses
Typical NDVI graphs for crop not affected by drought
Typical NDVI graphs for drought damaged crop
The analysis of crop rotation (ratio of late and other crops) based on the NDVI graphs for the time period of 2001-2010
Amount of years when late crops were cultivated
Amount of years when early crops were cultivated
average standard deviation
average standard deviation
Fields not affected by drought
6,45 0,83 3,55 0,83
Drought damaged fields
7,80 1,03 2,20 1,03
Relationship between the percentage of late crops in crop rotation and drought susceptibility of fields
Amount of years when late
crops were cultivated
Percentage of drought
damaged fields
Percentage of fields not
affected by drought
5 2 14
6 9 34
7 24 45
8 40 7
9 23 0
10 2 0
0
10
20
30
40
50
60
70
up to 6 years 8 years and more
percentage of drougtdamaged fields
percentage of fieldsnot affected bydrought
Relationship between the percentage of early crops in crop rotation and drought susceptibility of fields
Amount of years when early crops were cultivated
Percentage of drought
damaged fields
Percentage of fields not
affected by drought
0 2 0
1 24 0
2 40 7
3 23 45
4 9 34
5 2 14
0
10
20
30
40
50
60
70
up to 2 years 4 years and more
percentage of drougtdamaged fields
percentage of fieldsnot affected bydrought
Conclusion Crop rotation is one of the factors of crop damage
during drought period
Increasing of late (summer) crops in crop rotation is a risk factor of crop damage in dry period
MODIS data can be used for mapping of agricultural plots with high risk of crop damage in case of drought.