UGC NET Paper 1 Mathematical Reasoning & Aptitude.pdf
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An index to rate the quality of no-till systems: a conceptual framework.Glaucio Roloff
1. An index to rate the quality of
no-till systems:
a conceptual framework
Glaucio Roloff
Federal University of Latin-American Integration (UNILA)
Ramiro A. T. Lutz
Vetagro Crop Consultants
Ivo Mello
Brazilian No-Till Federation (FEBRAPDP)
Cooperation FEBRAPDP â ITAIPU Binacional
5th WCCA & 3rd FSD
Brisbane 2011
2. No-Till System (NTS): in Brazil
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Prevailing system for grains by far, especially within last 15 years
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~30 million ha, ~50% of total cropland
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Early adopters: an effective soil conservation technique
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Current reality:
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relatively stable yields and timely seeding
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saves fuel and time
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more crops over a time period, e.g. ...
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soybean/corn/oats (cover) â regular rainfall winters
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soybean/corn+Bracchiaria (cover and pasture) â dry winters
5th WCCA & 3rd FSD Brisbane 2011 2
7. NTS: current shortcomings in Brazil
Reasons for the non adherence to key components:
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Bollinger et al. (2006) Advances in Agronomy, 91, 47-64
â Farmers...
» âŠunable to afford cover crops and appropriate herbicides
» âŠinterested only in commercial crops
â Perceived need to till eventually to...
» âŠalleviate compaction
» âŠincorporate lime
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In addition
â Crop consulting dissociated from sustainability issues
â Agricultural policies dissociated from environmental policies
â Environmental policies ignore positive externalities from NTS
â Erosion and runoff no more seen as a problem
» complacency
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8. NTS in Brazil
Adherence to key components needs to be improved
⊠and hence improve NTS environmental services
How to gauge adherence?
Through a NTS quality index
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9. NTS in Brazil
CA key components cover all environmental externalities?
âą Kassam et al. (2009) International Journal of Agricultural Sustainability, 7, 292â320.
» Ideal CA soil should approach forest floor condition
...hence minimal water runoff (among others)
âą Usual NTS conditions far from ideal
» Inappropriate crop rotations â poor soil cover at times
» Compaction
âą Rainfall intensities often > stable infiltration rates
» up to yearly run-off events
Run-off management should be an explicit component of any
NTS quality assessment
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10. NTS Quality
NTS Quality
...capacity of a given no-till field to maintain or increase crop and
livestock productivity while maintaining or enhancing soil, water and air
quality and other environmental services.
NTS Quality Index (NTSQI) premises and development
âą based on a regional benchmark set of best practices
âą constructed from recognisable indicators â self-evaluation
âą sampling-free and non seasonal
âą specific to NTS
âą address directly or indirectly the four key system components
âą allow for the recognition of critically low key indicators
âą indicators defined by expert opinion and farmers input
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12. NTS Quality Index
NTSQI formulae
Ei Ii = ith indicator
Ii= Ei = current or future parameter value
Bi Bi = benchmark value
NTSQI= â ( Iiâ fi ) fi = subjective weighing factor
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13. NTS Quality Index
NTSQI test
âą 24 voluntary farmers over 6
small river basins
âą Questionnaire (assisted
evaluation)
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14. NTS Quality Index
Regionalised NTSQI parameters
Indicator Ei fi Bi Critical
RI Crops past 3 yrs 1.5 9 0.56
RD Crop species past 3 yrs 1.5 4 0.50
RP Grass cover crops past 3 yrs 1.5 6 0.50
TF Whole field tillage operations past 3 yrs 1.5 6 0.50
TA Run-off over-topping events past 5 yrs 1.0 ---- 0.50
Cumulative absence of downhill seeding,
CE whole field and edge compaction signs, and 1.0 4 0.50
visible erosion
BN Cumulative presence of manure addition, soil 1.0 3 0.33
sampling and nutrient balance
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AT Years of no-till adoption 1.0 22 0.33
16. NTS Quality Index
Conclusions:
âą NTSQI can be...
» ⊠used to rank farmers and basins to promote awareness.
» ⊠be a tool to prioritise actions to improve NTS quality and
hence of its environmental services.
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