Nutrient Management Mai Abbas Khadijeh Yasamin Shirazi Modules

Nutrient Management Mai Abbas Khadijeh Yasamin Shirazi Modules of Sustainable Agriculture (MOSA) August 2015

How Ecosystem works? Energy flow and Nutrient Cycles. https: //www. youtube. com/watch? v=o_RBHfj. Zs. UQ 2

Outline : I. general Facts about nutrients. II. Environmental and economic concerns. III. Principles of sustainable intensification. IV. Methods of sustainable nutrient management/good practices. 3

I. General Facts on Nutrients 4

Nutrients keytotosoil fertility andand plant growth Nutrients areare key fertility Large number with different needs: Macronutrients: • Nitrogen (N) • Phosphorus (P) • Potassium (K) Micronutrients: • Iron (Fe) • Manganese (Mn) • Cobalt (Co) • Boron (B) • Zinc (Zn) Mesonutrients: • Calcium (Ca) • Sulphur (S) • Magnesium (Mg) • Silicium (Si) • Sodium (Na) • Chlorine (Cl) • Nickel (Ni) • Molybdenum (Mo) Toxic elements to plants: Al, heavy metals 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 55

Nutrient Supply and Demand: Source: wikipedia 6

Nutrient Supply and Demand: Nutrient deficiency “soil mining ” Uneven distribution Over supply Intensive cropping Lack/minimal use of fertilizers for decades. Excessive mineral fertilizer Nutrient imports/fodder 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 77

Scarcity and over-supply Source: 8

Phosphorus Cycle Source: Wikipedia 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 99

P run-off and export Peak phosphorus refers to the moment when production of phosphorus from mining reaches a maximum, and after that point the quality of remaining phosphorus reserves decreases and becomes harder to access making it more expensive to mine and process. erosion Ironically, phosphorus represents both a scarce non-renewable resource and a pollutant for living systems in lakes rivers and oceans. harvest Run-off leaching Source: adapted from Tirado & Allsopp, Greenpeace (2012) 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 10 10

The Nitrogen Cycle Source: Cooper 2007 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 11 11

The Nitrogen Cycle. https: //www. youtube. com/watch? v=DP 24 Bce. Owt 8 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 12 12

Ø In the past 50 years. increases in anthropogenic nitrogen. Due to Haber-Bosch process. N 2(g) 2 NH 3(g) Source Harrison 3 H 2(g) 1. General 2. Environmental and economic 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 1. General facts 2. facts Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 13 13

Geochemical Nitrogen (which is mainly synthetically produced N) is one of three parameters (together with loss of biodiversity and global warming), which exceed planetary boundaries. In other words. The present use of synthetic nitrogen is highly unsustainable. 14

Summary : ü Nutrients are needed in the soil and for the plants growth. ü All the nutrient cycles should be closed (amount of input= output). ü Human activities especially application of fertilizers distributed the nutrient cycles. Since many minerals are added to the ecosystems 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 15 15

II. Environmental and Economic Concerns 16

The Dominance of nitrogen applications Share of Nitrogen (%) in the use of macronutrients (N, P, K) Year 1961 World Tanzania 49. 2 52, 6 1971 58, 6 71, 9 1981 64, 5 75, 3 1991 68. 4 79, 1 2001 71, 2 75, 6 2009 74, 0 94, 7 Kotschi 2013 Global application of fertilizers by nutrients (N, P, K) Ph. Kotschi 2013 Z 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 17 17

Nitrogen – Environmental and atmospheric impact Nitrogen environmental and atmospheric impacts: Agricultural emissions in (MT CO 2 eq) Ø Global warming. Ø Nitrogen depoistion leads to eutrophication of natural. ecosystems. (nitrophilic species) Source : Bellarby et al 2008 1. General facts 2. facts Environmental 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 18 18

Nitrogen – Environmental and atmospheric impact Ø Nitrogen deposition leads to increased tree growth. Ø The forest floor vegetation transformed to Ø Shrubs, grasses. Ø Forest decline and death of trees. Source: Van der erden, Fangmeier, Jäger, 2001 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 19 19

Soil acidification Synthetic Nitrogen - Adverse impact on soils Availability of phosphorus is limited(fixed with Al, Fe) Increase in the conc, of toxic metals Microorganisms life is impaired To neutralize the acidifying effect of a kilogramme of urea, which makes up 67% of global nitrogen fertilizer consumption, 0. 71 kg of lime is required. 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 20 20

Soil acidity and Phosphorus availability (example from Kenya) 1. General facts 2. facts Environmental 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 21 21

Plant nutrients have become very costly Terms of Trade for fertilizer and food fertilizer price index / food price index Photo: Kotschi 1. General facts 2. facts Environmental 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 22 22

For many smallholders returns from fertilizers are comparatively small Three- fold disadvantage: Ø Due to high transportation and handling costs, mineral fertilizers are comparatively costly. Ø Yield increases through fertiliser are often small due to low soil fertility. Ø Prices for agricultural products are often low due to limited access to markets and other factors 1. General 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable management 1. General facts 2. facts Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 23 23

Summary: ü Excessive nitrogen application, contributed to many environmental problems (soil acidification, global warming, . . ). ü Mineral fertilizers cost so much in developing countries due to: transportation, sold in small quantities. 24

III. Principles of Sustainable Intensification 25 25

Sustainable Intensification - squaring the circle? Ø Are sustainability and intensification contradictions? Ø Increase nutrient use efficiency Ø Main principles: • Close nutrient (and energy) cycles further • Speed up turn-over of nutrients 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 26 26

Sustainable Agriculture Fossil Energy Systems Elements: • Soil Mineral Fertiliser Farmer Family • Nutrients • Water Production • Biodiversity • Others tu a N l a r em t s y S Closing Nutrient Cycles Source: U. Hoeggel 1. General 2. Environmental and economic 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 1. General facts 2. facts Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 27 27

Soil Humus is paramount for sustainable nutrient management • Nutrient storage capability -> measured as Cation Exchange Capacity (CEC). • Cation exchange capacity of soils and their components (meq/100 g). • Soils with high humus content can storage the nutrient well. • High CEC is key for closing nutrient cycles. • In degraded soils -those with low soil fertility and minimal organic matter– nutrient losses can be enormous. 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 28 28

Soils with high humus content can utilize mineral fertilizers well Decomposition of soil organic matter: Ø Mineralisation is increasing with higher and on-sided nitrogen doses. Ø Low Soil Organic Matter (SOM) in many tropical soils particularly critical, due to their important nutrient storage function. 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 29 29

Summary ü Two main principles for sustainable intensification: • To create nutrient cycles, or to close and improve already existing cycles of nutrient. • Nutrient turn-over can be accelerated ü Soil humus is important for sustainable nutrient management. • High CEC is key for closing nutrient cycles. 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 30 30

IV. Methods of Sustainable Nutrient Management/ Good Practices 31 31

Monitor the nutrient status in your soils • Before fertilizing a field, nutrient status and p. H should be known. • Soil analysis is rarely done, but helps to place fertilizers more economically. There are two ways: • Laboratory analysis – precise but costly and time consuming. • Field test kits – less precise but reasonable, lowcost. Can be applied by farmers and can create awareness on nutrient issues. Source: eurocosm. com 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 32 32 31

Sustainable land-mangement practices (SLM) • Strengthen the linkage between cropping and animal husbandry. • Use compost and vermicompost. Source: backyardecosystem. com • Apply green manures and intensive fallows. • Include agroforestry. Source: outofmyshed. files. wordpress. com Source: agroforestry. eu 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 33 33

Animal husbandry for soil nutrient management • In particular a source of phosphorus and calcium. • Soil humus content can be maintained or even raised with manure. Photo S. Krall GIZ 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 34 34

Compost a next generation technology • Compost technologies are booming. • Of particular importance for smallholder agriculture. • Amounts are limited. • Provides organic fertilizers of high quality. • Vermi-compost of particular interest. Photo. Kotschi Vermi-compost production in Madagascar 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 35 35

Take action against soil acidification • Dispense with acidifying fertilizers (urea, ammonium nitrate, ammonium sulphate); instead: organic fertilizer and nonacidifying mineral fertilizers (e. g. calcium cynamide, calcium ammonium nitrate and calcium nitrate). • Apply systematic liming: on-farm resources such as wood ash or earth from termite mounds, and particularly processing and supply of ground lime from local limestone. Photo: C. Arndt 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 36 36

Improve Phosphorus supply • Increase supply and use of phosphorus fertilizers (and recycling). • Tap local phosphate deposits and apply small scale production of phosphate fertilizers. 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 37

From synthetic to biological nitrogen • More sustainable N-supply is needed • Biological N-supply has advantages – but is it sufficient? • Research needed for a transition to more biological nitrogen. Photo Kotschi 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 38 38

Definition of green manure /cover crop a “green manure/cover crop” is a species of plant, usually a legume, whether it is a tree, a bush, a vine, A crawling plant or an algae, which is planted by farmers to maintain or improve their soil fertility or control weeds, even when they have many other reasons for growing these plants. 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 39 39

Green manures and intensive fallows • Wide range of methods and technologies available. • Main impact: additional biomass and nitrogen. • Impact on crop yields is high. • Impact on soil humus smaller compared to compost and manure. Ground covering legumes, Nigeria Photo Kotschi Manuring of paddy soils in China 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 40 40

Nutrient gains through agroforestry Coffee in agroforestry in Peru Inga sp. in Honduras Source. http: //www. rainforestsaver. org/es/manual-agroforestal-del-inga Acacia albida, Senegal Photo Kotschi source: http: //www. cifor. org/rehab/_ref/countries/Peru/Initiatives. amazonas. htm Photo Kotschi 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 41 41

Summary ü Methods of sustainable nutrient management • Monitor the nutrient status in your soils. • Sustainable land-mangement practices (SLM). • Animal husbandry for soil nutrient management. • Compost as a next generation technology. • Take action against soil acidification. • Improve phosphorus supply. • From synthetic to biological nitrogen. • green manure /cover crop. 1. General facts 2. Environmental and economic concerns 3. Principles of sustainable intensification 4. Methods of sustainable nutrient management 42 41

Thank You 42 43

References http: //www. backyardecosystem. com/wp-content/uploads/2010/12/vermicomposting 72. jpg https: //outofmyshed. files. wordpress. com/2011/03/green-nanure-chopped-up. jpg http: //www. agroforestry. eu/sites/default/files/pub/styles/galleryformatter_slide/public/photo 36. jpg ? itok=b 68 JRr 95 45 46