meat bone meal as nitrogen and phosphorus fertilizer master´s thesis agroecology university of

60 Pages·2008·0.25 MB·English

MEAT BONE MEAL AS NITROGEN AND PHOSPHORUS FERTILIZER
MASTER´S THESIS
AGROECOLOGY
UNIVERSITY OF HELSINKI
DEPARMENT OF APPLIED BIOLOGY
OCTOBER 2008
CHEN LIN
HELSINGIN YLIOPISTO(cid:190) HELSINGFORS UNIVERSITET(cid:190) UNIVERSITY OF HELSINKI
Tiedekunta/Osasto(cid:190) Fakultet/Sektion(cid:190) Faculty Laitos(cid:190) Institution(cid:190) Department
Faculty of Agricultural and Forestry
Department of Applied Biology
Tekijä(cid:190) Författare(cid:190) Author
CHEN Lin
Työn nimi(cid:190) Arbetets titel(cid:190) Title
Meat bone meal as nitrogen and phosphorus fertilizer
Oppiaine(cid:190) Läroämne(cid:190) Subject
Agroecology
Työn laji(cid:190) Arbetets art(cid:190) Level Aika(cid:190) Datum(cid:190) Month and year Sivumäärä(cid:190) Sidoantal(cid:190) Number of pages
MSc thesis October, 2008 58
Tiivistelmä(cid:190) Referat(cid:190) Abstract
Meat bone meal (MBM) contains considerable amount of nutrients (~8% N, ~5% P and ~10 Ca).
So it can be a potential organic fertilizer for different crops. Traditionally, the production of
mineral N and P fertilizers is unsustainable due to the reliance on fossil fuels in case on N, and
limited mineral resource stocks in case of P. Using complementary fertilizers which originate
from organic waste materials is gaining interest. On the other hand, organic farms are usually
lacking nutrient sources if animals are not kept on farm at the same time. Whether MBM can
achieve similar crop yield and quality as the mineral fertilizer was studied. To quantify and
qualify MBM use as an N and P fertilizer, two field experiments were done on spring barley and
oat in 2000 and 2001. MBM and two types fur animal manure based fertilizers (FAMB and
FAMBCF) were compared to mineral fertilizer PellonY3 in three N levels: 60, 90 and 120 kg/ha.
MBM and FAMBCF gave the same grain yield as PY3. There was no additional yield increase by
increasing N rate from 90 to 120 kg/ha. Four aspects of grain quality, namely 1000 grain weigh,
test weigh, protein content and protein yield were tested. MBM, FAMBCF and PY3 tended to
have similar effect while FAMB had lower effect. Since MBM has a low N/P ratio, when it is
applied to meet crop's N demand, P will be at surplus. So using crop rotation and green manure
for organic farm and only applying N fertilizer for conventional farm after using MBM is
recommended. Adding K in MBM is also necessary when there is a lack of K in soil since MBM
had only ~1% K.
Avainsanat(cid:190) Nyckelord(cid:190) Keywords
meat bone meal, nitrogen, phophorus , organic fertilizer
Säilytyspaikka(cid:190) Förvaringsställe(cid:190) Where deposited
Helsinki
Muita tietoja(cid:190) Övriga uppgifter(cid:190) Further information
CONTENTS
1. INTRODUCTION.............................................................................................................1
1.1 NITROGEN AND PHOSPHORUS FERTILIZERS..................................................1
Mineral nitrogen and phosphorus fertilizers ................................................................1
Environmental stress from fertilizer use .......................................................................3
Organic fertilizer.............................................................................................................5
Nitrogen and phosphorus balance at farm level ..........................................................7
Yield curves and economic reward analyses ...............................................................8
1.2 MEAT AND BONE MEAL.......................................................................................10
Nutrient content ............................................................................................................10
History of use ................................................................................................................10
Disposal and recovery in Finland ...............................................................................11
MBM as nitrogen fertilizer...........................................................................................11
MBM as phosphorus fertilizer......................................................................................13
1.3 INDUSTRIAL ECOLOGY........................................................................................13
Background....................................................................................................................13
Nitrogen and phosphorus fertilizers production in IE................................................15
Nitrogen and phosphorus flow in food system............................................................17
1.4 AIMS OF THE STUDY.............................................................................................18
2. MATERIALS AND METHODS...................................................................................20
2.1 STUDY AREA............................................................................................................20
2.2 MATERIALS USED IN THE EXPERIMENT........................................................21
Barley variety ...............................................................................................................21
Oat variety ....................................................................................................................21
The four fertilizers in the experiment...........................................................................21
2.3 EXPERIMENT DESIGN...........................................................................................22
2.4 CROP MANAGEMENT............................................................................................23
2.5 DATA MEASUREMENT..........................................................................................23
2.6 DATA ANALYSIS.....................................................................................................23
I
3 RESULTS..........................................................................................................................24
3.1 BARLEY EXPERIMENT RESULTS.......................................................................24
Barley grain yield .........................................................................................................25
Barley 1000 grain weight (TGW) ...............................................................................26
Barley grain test weight ...............................................................................................27
Barley grain protein content .......................................................................................27
Barley grain protein yield ............................................................................................29
3.2 OAT EXPERIMENT RESULTS...............................................................................29
Oats yield ......................................................................................................................29
Oats 1000 grain weight (TGW)....................................................................................30
Oats test weight ............................................................................................................30
Oats protein content .....................................................................................................31
Oats protein yield .........................................................................................................32
4. DISCUSSION ..................................................................................................................34
4.1 BARLEY AND OAT GRAIN YIELD......................................................................34
Fertilizer type factor ....................................................................................................34
Nitrogen level factor ....................................................................................................35
4.2 BARLEY AND OAT GRAIN QUALITY................................................................35
1000 grain weight ........................................................................................................35
Test weight ....................................................................................................................36
Protein content .............................................................................................................36
Protein yield..................................................................................................................36
4.3 PRACTICAL UTILIZATION OF MBM..................................................................36
4.4 CONCLUSION...........................................................................................................38
REFERENCES................................................................................................................40
ACKNOWLEDGEMENTS...........................................................................................46
APPENDICES .................................................................................................................47
II
1. INTRODUCTION
1.1 NITROGEN AND PHOSPHORUS FERTILIZERS
Mineral nitrogen and phosphorus fertilizers
Nitrogen is an essential nutrient to all plants and is crucial for all life on earth. It is in all
amino acids and nucleic acids such as DNA and RNA. In plants, much of the nitrogen is
used in chlorophyll molecules which are essential for photosynthesis and further growth.
Nitrogen also helps plants with rapid growth, increasing seed and fruit production and
improving the quality of leaf and forage crops.
Since Justus von Liebig found that nitrogen is the main growth limiting nutrient to plants,
producing nitrogen fertilizer has been studied extensively. 70% of the atmosphere is
consisted of molecular nitrogen (non reactive nitrogen), which can not be used by plants
due to its strong bond. There are four ways to fix nitrogen to a reactive form Nr (Reactive
nitrogen) that is useful to higher organism (Fig. 1). Biologically, it can be performed by a
number of specific bacteria, most often associated with leguminous plants (i.e.,
ammonification), then oxidized to inorganic forms (i.e., nitrification) that are assimilated
by plants (NO ). The non biological processes include lightning, industrial Haber
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Bosch process, and combustion. On the contrary, NO may also be denitrified by
3
bacteria, producing N , NOx, and N O.
2 2
The Haber–Bosch process invented in the 1910s made it possible to manufacture the Nr
as fertilizer needed to meet the growing demand in food and fibre worldwide (Smil 2002).
Now about 100 million tons of nitrogen fertilizers are produced by Haber–Bosch process
every year, mostly in the form of anhydrous ammonia, ammonium nitrate, and urea (Smil
2004). It is estimated that about 40% of the current six billion people rely on synthetic N
fertilizers produced by Haber Bosch process (Galloway et al. 2002).
Like nitrogen, phosphorus is one of the three macronutrients added to soils. It is mostly
important to young tissues, flowering and seed formation. It is especially in demand for
1
Nitrogen in
atmosphere (N2)
Denitrifying
bacteria
Animal Plant Assimilation
Nitrogen
fixing
bacteria in Decomposition Nitrates
root nodules (NO3 )
of legumes AAereorboicb aicn dand
anaerobic
anaerobic bacteria
bacteria and
anfdu nfugnigi Nitrifying
bacteria
Nitrogen Ammonification
fixing soil
Nitrification
bacteria Ammonium Nitrites
(NH4+) (NO3 )
Figure 1. The nitrogen cycle in a soil plant system (Source:Brady & Weil 2002, revised).
cereal production, which contain about 0.25 0.45% phosphorus, more than in any other
plant tissues.
Phosphorus is commonly found in inorganic phosphate rocks, which is the major resource
mined to produce phosphate fertilizers for the agricultural sector. It is a limited resource
and scientists are now claiming that a "Peak Phosphorus" will occur in 30 years and that
"at current rates, reserves will be depleted in the next 50 to 100 years" (Lewis 2008).
The phosphorus cycle is much simpler compared to nitrogen cycle because phosphorus
seldom has an atmospheric connection and is less subject to biological transformation
(Busman et al. 1997). Phosphate is taken up by plants from soils, utilized by animals and
returned to soils in organic form. The mineralization by microorganisms can transfer
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Fertilizer Plants Animals Humans
Loss in
eroded
Plant residues, manure particle
and sludge s
Loss in
Readily Soil
Very slowly
runoff
soluble Ca P soluble Ca P solution
Immobilization
minerals
Soil organic
Minerali biomass
zation
Desorption
P retained by iron,
aluminum oxides P in active soil
organic matter
Absorption
P in slow and passive
P occluded in iron and soil organic matter
aluminum minerals
extremely insoluble
Organic forms of P
Inorganic forms of P
Figure 2. The phosphorus cycle (Source: Brady & Weil 2002).
organic phosphate to inorganic phosphate which plants can use (Fig. 2). Most soils have a
large capacity to retain phosphorus; even large addition of phosphorus will be mostly
retained if there is adequate contact with the soil (Busman et al. 1997). Phosphate can be
lost through soil erosion and leaching.
Environmental stress from fertilizer use
Global fertilizer consumption has increased substantially since 1950, while the world's
population has grown from 2.5 to 6 billion. According to FAO's forecasts of worldwide
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crop yield and areas, in order to meet the future crop demands, fertilizer consumption will
have to increase from the present level of 138 million tons N+P O +K O to between 167
2 5 2
and 199 million tons per year by 2030 (Daberkow et al. 2000).
Delwiche (1970) stated that in absence of human activity, the N from non reactive to
reactive forms and back again is about balanced, which means there is no accumulation
of reactive N. Large scale production of ammonium started from 1913, and after 1950s,
N fertilizer applications had increased to 85 million tonnes by the late 1990s, and it will
be still growing rapidly as predicted by FAO (Smil 2002). Roy et al. (2002) estimated
that the global annual N O and NO emission from agriculture amount to 3.5 and 2.0
2
million tons respectively. Human induced increase of Nr cause both beneficial and
detrimental effects to human health and ecosystem (Galloway et al. 2002).
When mineral fertilizers are applied to the fields, the N use efficiency is quite low in
reality. Nitrogen can be lost from the plant soil system through leaching, runoff, erosion,
and gaseous emissions. The relative importance of each of these pathways depends on
soil conditions. In irrigated fields or where the precipitation exceeds evapotranspiration,
leaching is the main cause of N loss, while gaseous loss usually takes place in two forms,
volatilization and denitrification, resulting in the release of NH , NO, N O and N to the
3 2 2
atmosphere (Roy et al. 2002).
Emitted Nr can lead to harmful heath effects to human being through indoor and outdoor
air pollution, increasing human respiratory and cardiac disease. It can also affect health
through water pollution, for example algae blooms that are caused by excess of the
nutrient can be toxic to humans (Wolfe 2002). Increased NOy (NOy=NO (NO+NO ) +
X 2
any other single N species with an oxygen atom) from fossil fuels combustion and NHx
(NH =NH + aerosol NH +)from animal agriculture often lead to acidification of forests,
X 3 4
soils, and freshwater (Rabalais 2002). High rates of Nr input lead to losses of biodiversity
in terrestrial and aquatic ecosystems. The N saturation of soils in terrestrial ecosystems
increases export of Nr to downstream aquatic environments, resulting in high ground
4
water nitrate levels above accepted standards and the rise of incidence in red tides
(Matson 2002).
Understanding of how to both produce food and protect the environment at the same time
is crucial for sustainably meeting the increasing demand in agricultural production.
Galloway (2002) suggested that there are three specific needs: 1) a decrease in Nr created
by the Haber Bosch process; 2) an increase in the efficiency of Nr use in food production
(including recycling of agricultural waste); 3) an increase in denitrification of Nr that can
not be recycled. The first decreases the Nr produced, the second keeps Nr in the
agroecosystem, and the third eliminates Nr before it can leak to the environment.
For phosphorus fertilizers, mismanagement of soil P can pose a threat to water quality.
When P is leaching to the lakes and rivers, excessive growth of algae often results. It can
reduce water clarity and decrease available dissolved oxygen, which has detrimental
effect to aquatic organisms.
On the contrary, under use of fertilizers can result in loss of soil fertility and cause soil
biological and physical structure degradation (Norse 2003). Nutrients were depleted at
the rate of 54 kg /ha per year in Africa and Latin America in 1993 1995 (Wood et al.
2004). Not only low input system can result in nutrient depletion, but also when NPK are
not balanced, especially when P is too low compared to N and K (Murgai et al. 2001).
Organic fertilizer
Organic fertilizer is derived from the remains or a by product of an organism. Naturally
occurred organic fertilizers are manure, slurry, worm castings, peat, seaweed, sewage and
guano. Manufactured organic fertilizers include compost, blood meal, bone meal and
seaweed extracts, etc. Before Haber–Bosch process was invented, there were mainly
three ways to provide nitrogen in agriculture: recycling organic waste (crop residues,
animal and human waste), using crop rotation with N fixing leguminous species, and
planting of leguminous cover crops (Smil 2002). The green manure plants, such as clover
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and vetch contain nitrogen fixing symbiotic bacteria in root nodules which can fix
atmospheric nitrogen in a form that plants can use.
Organic fertilizers increase the organic content and consequently the water holding
capacity of the soil. They improve the physical structure of the soil which allows more air
to get to plant roots. Where organic sources are used for fertilizer, bacterial and fungal
activity increases in the soil. Mycorrhizal fungi which make other nutrients more
available to plants thrive in soil where the organic matter content is high. Organic
fertilizers need soil organisms to break them down to release nutrients; therefore, most
are effective only when soil is moist and warm enough for the microorganisms to be
active. As the costs of mineral fertilizers rising; using organic fertilizer can keep the
farmers more independent. Poutala et al. (1994) revealed that the greatest gross margin
/crop economic return among ecological, integrated and conventional nutrient systems in
cereal cropping were achieved under ecological nutrient management.
The traditional farming relies on recycling organic wastes, which remains an important
ingredient of well balanced modern agriculture (Smil 2002). With the growing scientific
knowledge in plant nutrition and awareness about the finiteness of some natural resources,
like phosphorus and fossil energy (needed for industrial nitrogen fixation), the
possibilities of recycling the nutrients from the communal and industrial wastes to
agriculture is gaining more interest (Werner 2003). It was estimated that, the potential
amounts in these complementary sources in EU are 729 000 tons N, 472 000 tons P,
245 000 tons K in all (Werner 2003). There is a high amount of nutrients in wastes,
residues, and by products. Recycling and using them in agriculture is an efficient tool of
nutrient management. Possible risks with respect to soil and water pollution as well as to
food chain can be removed by proper composting and some other methods, such as
heating in some materials (Werner 2003).
Compared to mineral fertilizers, the composition of organic fertilizers are usually more
complex and variable. And for same amount of nutrient, organic fertilizer need larger
amount of material. Cost of transport and consideration of convenience provide
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