Organic-Agriculture with special reference to organic manures and their environmental implications

Promoting organic agriculture for healthy environment and greener future

1. CREDIT SEMINAR

Organic Farming
With Special Reference
To
Organic Manures and
Their Environmental Implications

Speaker:
Vivek Kaila (A-2007-30-07)
M.Sc. AGRONOMY

2. History =

* Organic movement began in © 1930s and 1940s as a reaction to
agriculture's growing reliance on synthetic fertilizers.

* Artificial fertilizers had been created during the 18" century,
initially with superphosphates and then ammonia derived
fertilizers mass-produced using the Haber-Bosch process
developed during World War I.

* Sir Albert Howard is widely considered to be the “father of
organic farming”.

* Rudolf Steiner , an Austrian philosopher, made important
strides in the earliest organic theory with his biodynamic
agriculture.

3. What is Organic Farming? ”

“Organic farming is a production system that sustains the health of soils,
ecosystems and people. It relies on ecological processes, biodiversity
and cycles adapted to local conditions, rather than the use of inputs with

adverse effects. Organic farming combines tradition, innovation and
science to benefit the shared environment and promote fair relationships

FOAM, 2008

and a good quality of life for all involved.”

4. Types of organic farming

=
Mo rming

Biodynamic

Y farming

5. QO

ORGANIC FARMING SYSTEM

6. PRINCIPLES of ORGANIC FARMING a

O

* The principle of health — Organic farming should sustain and enhance
the health of soil, plant, animal, human and planet as one and
indivisible.

* The principle of ecology — Organic farming should be based on living
ecological systems and cycles, work with them, emulate them and help
sustain them.

* The principle of fairness — Organic farming should build on
relationships that ensure fairness with regard to the common
environment and life opportunities.

* The principle of care — Organic farming should be managed in a
precautionary and responsible manner to protect the health and well-
being of current and future generations and the environment.

7. COMPONENTS OF ORGANIC FARMING

Organic manures

Non-chemical weed control

Prevention

Cultural Practices

Mechanical Practices

Competitive plant species

Stale seed bed technique

Biological weed management
Bio-herbicides.

Biological pest and disease management
Conservation of natural enemies of pests
Resistant varieties

Crop rotations

8. ORGANIC MANURES AND ORGANIC FARMING

- Manure is organic matter used as organic
fertilizer in agriculture.

* Manures contribute to the fertility of the soil by
adding organic matter and nutrients, such as
nitrogen that is trapped by bacteria in the soil.

9. ORGANIC MANURES COMMONLY
IN USE IN ORGANIC FARMING

“Farm Yard Manure
“Green manure
°Vermi-compost
°Crop residues

*Bio-fertilizers

10. FARM YARD MANURE

* Commonly used Organic manure
* Readily available
* Important agricultural By-products
+ Advantages
+ Ability to improve the soil, tilth $
aeration.
+ Increases the water holding capacity
of the soil
* Stimulate activity of micro-organisms
that made plant food elements in the
soil readily to crops

11. Average percentage of N, P,O, and K,O in the fresh excreta of farm

animals
Animal refuse N% CASE K,O
Cattle dung and 0.60 O45 0.45
urine mixed(fresh)
Poultry manure Osa] 1.4-1.8 0.8-0.9
(fresh) |
FYM (DRY) 0.5-1.5 0.4-0.8 0.5-1.9

12. Green manures A

>» Green manure is a type of cover crop grown primarily to add
nutrients and organic matter to the soil.

> The practice of ploughing or turning into soil under-composed
green plant tissue for the purpose of improving physical
condition as well as fertility of the soil is referred to as Green
Manuring.

> The green manure crops should have:
profuse leaves and rapid growth early in its life cycle.
have abundance and succulent tops
be capable of making a good stand on poor and exhausted soils.
have a deep root system.
be legume with good nodular growth habit.

13. Common leguminous green-manuring crops and the []

potential
Name Botanical name Av. yield of green N% N added
matter (q/ha) (kg/ha)
| Kharif
|
Sun hemp Crotalaria juncea 152 0.43 84.0
|Dhaincha | Sesbaniaaculeata | 144 | o42 [771
| Mung Phaseolus aureus 57 0.53 | 38.6
| Cowpea | Vigna sinenis | 108 0.49 | 56.3
| Rabi
| Mellilotus alba
Kesari Lathyrus sativus 88 0.54 61.4
Berseem Trifolium 111 0.43 60.7 |
alexandrinum | |

14. |
A

Vermicompost

+ Vermicompost is a stable
fine granular organic
matter, when added to soil
loosens the soil and provides
passage to air.

+ The mucus attached to the
cast being hygroscopic in
nature improve WHC of the
soil.

15. Average nutrient composition of N

vermicompost

(%) Micronutrients (ppm)
N 15 Fe 3200
E 0.9 Mn 357
K 0.26 Zn 80
Ca 1.26 Cu 41

Mg 0.61

Ss 0.16

Besides these nutrients, it contains growth hormones, vitamins, enzymes,
Microflora like Phosphorus solublizing bacteria, N fixers, VAM fungi are also
present

16. De FERRE OS of mature crop residues such as dried
wheat straw, rice straw, paddy husk etc. in soil is not
a common practice of manuring but it has been
observed by many workers that if such substances

are ploughed in the soil, they have high: nutritional

17. Organic matter quantity and nutrient potential fron []
different sources of crop residues

Agricultural
wastage

Rice
Wheat

Residual
quantity
(mt)
110.5
82.6

Sorghum

21.0

Maize

125

Pearl millet
Barley
Finger Millet
Sugarcane
Pulses

15.6
25
53
40.9
33

Total

312.6

_ Lal & Kimble (2000)

18. Q
Biofertilizers

Bio-fertilizers refer to various inoculants or cultures containing a specific
micro-organisms in concentrated form, which are derived either from nodules
of plant roots or from the soil of root zone (rhizosphere). And posses unique
ability to fix atmospheric N either by living symbiotically with the roots of
feguminous plants or non-symbiotically (free living) or to transfer native soil
nutrients such as P, Zn, Cu, Fe, S etc. from the non-usable (fixed) form to

usable form through biological processes.

19. TYPES OF BIOFERTILIZERS Q

—_— — Symbiotic
Nitrogen

fixing
Biofertilizers .
Phosphate

solublizers

Free living

20. NITROGEN FIXERS

+ Rhizobium — for legumes

+ Azotobacter — for non-legumes
+ Azospirillum — for non-legumes
+ Acetobacter — for sugarcane

P-SOLUBILIZERS AND
MOBILIZERS

+ PSB - for all crops

* VAM — for all crops and
plants

O

1

21. POTENTIAL OF DIFFERENT EI

BIOFERTILIZERS

Rhizobium
Azotobacter
Azospirillum
Acetobacter

PSB

VAM

30-100 kg N/ha/season
20-35 kg N/ha/season
30-35 kg N/ha/season

70-150 kg N/ha/season
20-30 Kg P/ha/season

30-50 Kg P/ha/season

22. Organic Farming

and

Crop Production

23. CROP YIELDS

«>

24. Yields of organic and conventional crops

¡Crop | Conventional Crop | Conventional |
Wheat 4.0 7.7 to 8.5 Potatoes 25 42.5
(winter)

Wheat 32 5.8 Cabbage 25 to 35 30
(spring)
Barley 47 | 6.4 ‘Carrots 36 45
(winter)
Barley 42 5.8 Onions 20 35
(spring)
Oats 4.0 6.8 Apples 10.4 13

(winter)

Oats 35 oo
(spring)

25. QO

Yield of cotton from Conventional and Organic
Farming Systems

Year Status Yield (Qtis/ha)

Conventional

irst Year Under conversion 5.00
Second Year Under conversion

hird Year Organic 6.25

26. N

Grain yield Straw yield Net return
Treatment (q/ha) (q/ha) | (Rs/ha)
| No organic 32.38 46.61 18,932
| FYM (5 t/ha) 37.16 51.95 21,240
FYM (7.5 t/ha) 40.82 56.21 23,637
| FYM (10t/ha) 43.76 59.80 25,459
Vermicompost (1 .5t/ha) 41.81 57.00 23,943
Vermicompost (3.0t/ha) 48.96 63.84 27,128
Vermicompost (4.5t/ha) 52.64 67.96 27,831
CD 2.39 2.93 1,646
N(40 kg/ha) 47.18 63.17 27,718
N(60 kg/ha) 50.08 67.34 30,087
CD (P=0.05) 1.07 1.71 682

27. Comparison of Rice yield obtained under organic anc Q
conventional management

= Wet Season Dry Season Average*

[Conventional 2,445 3,507 2,976
[Organic | 3,918 4,822 | 4,370

Pasas of four (4) cropping seasons for Organic, while 2 cropping season for
‘Conventional.

TC Mendoza,2002

28. Relative yield and composition of vegetables grown with compost.
manure compared with mineral fertilizers; results of a 12 year experiment

Yield: 24% lower

Desirable components: 23% higher dry matter
18% more protein
19% more total sugar

13% more methionine
77% more iron
}

18% more potassium

10% more calcium
13% more phosphorus
Undesirable components: 12% less sodium

93% less nitrate

r
42% less free amino acids

29. Differences in vitamin C between organic and convention
vegetables in five studied vegetables

Vegetable Vitamin C
(%)

Lettuce +17
Spinach +52
Carrot -6

Potato +22
Cabbage +43

High nitrogen fe > | =
vitamin C in many ent \ H Worthington V., 2001

+ and — signs refer to conventionally grown crops as f
baseline for comparison |

30. Environmental
implications

31. Conventional agriculture meee D to environmeı []

so 2

° Uses synthetic fertilizers and pesticides that require
significant amounts of energy to manufacture.

° Applies excessive amounts of nitrogen fertilizer that
is released as nitrous oxide.

* Operates intensive livestock holdings that over
produce manure and methane.

32. Greenhouse gas emissions From Different Sectors

Waste water —— __— Agriculture
% 14%

Energy supply.

26%
Industry
19%
Transport
13%
Forestry
17%
Buildings

8%

The greenhouse gas emissions from all sectors related to

agriculture may potentially sum up to 25-30% of all GHG

33. Main sources of greenhouse gas emissions i
the agricultural sector

Rice production
Enteric (CHa), 11%

fermentation
(CH, ), 32%
Manures (CH, +
NO), 7%

Soil emmisions

Biomass burning. (CH, +
(CH, + N,0}, 38%
NO), 12%

Smith ef al. (2007)

N

34. a

Organic Farming mitigates climate change ?

O

* Reduces greenhouse gases, especially nitrous oxide, as no
chemical nitrogen fertilizers are used and nutrient losses
are minimized.

* Stores carbon in soil and plant biomass by building organic
matter, encouraging agro-forestry and forbidding the
clearance of primary ecosystems.

* Minimizes energy consumption by 30-70% per unit of land
by eliminating the energy required to manufacture
synthetic fertilizers, and by using internal farm inputs, thus
reducing fuel used for transportation.

35. Air quality

* As aoneseguenoe cf the phibition of dhienical fertilizar the
dret emissans cf nitrous oxide (NO) fromthe sail will be
recliced, this will be countered to sore degree by an incressed
fixation of nitrogninthesäl.

+ Cabo dodce (CO) from direct ar indirect use of fossil
energy isreclined duetoless cpenchnce on outs deinputs

* Recidicn in the number of animals the isn cf meihene
fran the dossive proossses in livestock and fran the
dscomposition of livestock menure a so denesses

36. Emissions of GHG from the agricultural sector O
under conversion in EU

| HG | Conventional | Partial conversion | Full conversion |

emmisions

| || Emissions Il Change Il Emissions Il Change ||Emissions |
CH, 164.5 -0.3% 164.0 -10% 148.1
emissions
N,O 218.8 -1.5% 2155 -50% 109.4
emissions
Co; 30.4 -2.4% |

29.7 | -80%

Emi

ions in Tg CO, equivalents ]

37. q
Soil Quality

Soil quality relates directly to the functions performed by soil

“High-quality soil is able to produce abundant plant materials, which
feed, clothe, and provide shelter to humans.

High-quality soil protects the environment from degradation, by
reducing soil erosion and nutrient runoff (i.e. water quality
protection) and by storing carbon in soil and reducing greenhouse
gas emissions.

“Low-quality soil lacks sufficient organic matter to sustain
productivity in the long term, leads to excessive soil erosion and
poor water quality, has low soil biological activity and diversity, id
could lead to an unhealthy food supply and human condition.

38. Chemical Biological
property property

Treatments | Bulk Organic Available Bacteria] Fungi

Physical property

density WHC% | carbon | Nitrogen 1 1

Mg/m>? % kg/ha Saa a
Control 1.42 35:8 0.28 | 191 55 6
100 % N as Urea 1.42 35:7 0.30 242 68 9
100 % N as FYM 1.26 42.8 0.70 236 277 12
100 % N as vermicompost 127 48.6 0.73 243 288 17
75% N as FYM with azospirillum 1.29 42.7 0.74 247 233 47
75% N as vermicompost with 132 441 0.78 253 393 28
azospirillum
50% N as FYM with azospirillum 1.37 39.0 0.60 220 150 13
A E a ee 39.4 063 | 225 159 14
with azospirillum
SED 0.017 4.3 0.01 1.3 5.4 i:
CD (P=0.05) 0.04 | 2.7 0.02 2.6 11 2.0

E Kannan et al. (2005)

39. Water Quality

© The agricultural nutrient of particular concern to
water quality and human health is nitrate.

O Nitrate, the common form of nitrogen in soils, is
subject to leaching because nitrate is negatively
charged.

© Negatively charged nitrate is repelled by negatively
charged soil particles. Thus, it is easily transported
down through the soil profile and into the
groundwater.

40. Nitrate leaching

Treat nt and subplots | Annual NO, leaching,g of NO.
| at 100 cm

Organic Compost 241.26

Integrated CaNO, + compost 772.83

Conventional CaNO, 1352-52:

Conventional

Harold et al. (2006)

Organic

Annual nitrate leaching was 4.4

higher in conventional plots than in organic
plots, with the integrated plots in between.

41. © Apart from NO, the water quality is also
improved due to the absence of the
harmful agrochemical residues which
otherwise escape into the under ground
water regime when used indiscriminately
under conventional management system.

42. Biodiversity
+ Biodiversity is an insurance for the future. It provides
the variability on which every species relies to help to

adapt to change. For this reason alone, it is important
to maintain, or improve biodiversity.

43. Biodiversity (Contd

Earthworm | Higher eantecmn abusa + under orga BB

management

Pfiffner and Mader
(1887)

Butterflies sf bunerfies on organic | Feber el af, (1207)

(2003)

Huston and ‘Giller

Spidara | ar 0 : under a | + did
vi: (2003)

44. Constraints

> There is reduction in yield initially (During
Conversion period)

> Lack of technical support and first hand market
information

45. Future thrust

* Protecting the long-term fertility of solls by maintaining
organic matter bevels, fostering soil biological activity and
careful mechanical intervention;

“ Providing crop nutrients indirectly by using relatively insoluble
nutrient sources which are made available to the plant by the
action of soil microorganisms;

+ Nitrogen self-sufficiency through the use of lequmes and
biological nitrogen fixation, as well as effective recycling of
organic materials including crop residues and livestock wastes;

Contd...

46. - Weed, disease and pest control relying primarily on crop
rotations, natural predators, diversity, organic manuring,
resistant varieties and limited (preferably minimal) thermal,
biological and chemical intervention:

- The extensive management of livestock, paying full regard to
their evolutionary adaptations, behavioral needs and animal
welfare issues with respect to nutrition, housing, health,
breeding and rearing;

« Careful attention to the impact of the farming system on the
wider environment and the conservation of biodiversity.

47. Organic agriculture is a viable alternative because it colivens the soil.
strengthens the natural resource base and sustnins biological production
na levels to commensurate the carrying capacity of the managed agro
CPE LR

In addition to this export market can also be tapped by group ini mes

inorganic Fanming. ln a country li India, food production has bo grow
steadily. A sudden switch over to organic farming is not feasible.

There is acute dearth of cvedences to show comparative crop
performance under pure organic fürming and intensive agriculture, in
terms of crop productivity and food quality, The introduction and
adoption of biological; and organic plant protection measures on 4 mass
scale may be a hill sur ask im Indian farming. In intensive farning
integrated and judicious ase of all the inputs including the fertiliners and
organic sources. coupled with minimal use of pesticides may be beter
choice than pure organic funming.