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1 This presentation is based on the research and experimental work done by the Biodynamic Research Institute and at the experimental farm Skilleby. The focus of this presentation is on soil fertility, plant nutrient conservation related to environmental protection and nutrient pollution to the Baltic Sea and finally the climatic consequences. The map of Skilleby experimental farm in this picture shows the location of the on-going long term trials comparing different fertilizer applications on each field in the five year crop rotation established in These experiments are based on earlier long term field trials carried out between 1958 and 1990, the first and longest scientifically documented trials comparing the effects of different farming methods on soil and crops (Koepf, Schaumann & Pettersson, 1976; Dlouý, 1981; Pettersson, 1982; Granstedt, 1990;1992). 1

2 The flow of energy from the sun, the recycling of nutrients and matter and the diversity of living organisms in interaction give us the air we breathe, the water we drink and the food we eat. Birth and death feed on and into each other. In a balanced ecosystem the synthesis of complex organic substances through the photosynthetic capacity of green plants is in equilibrium with the decomposition and combustion of organic matter. Our future is now threatened because the decomposition of organic matter and the combustion of fossil carbon compounds are greater than the synthesis by green plants Without recycling in agriculture and other sectors non-renewable resources are exploited and released into the environment resulting in more and more pollution. The global growing surplus of carbon dioxide and other greenhouse gases in the atmosphere and the regional surplus of nitrogen and phosphorus compounds in the soil and water systems together with increasing amounts of poisonous chemicals is the challenge of our time. Ecological techniques and a changed lifestyle can solve these problems if we take command over our lives. Artur.Granstedt@jdb.se 2

3 The famous Keeling carbon dioxide curve (named after the researcher who discovered it) illustrates both the progressive increase of the carbon dioxide in the atmosphere and the seasonal variation. The peak is in May after which the green leaves in the vegetation in the northern hemisphere assimilate coal from the atmosphere through photosynthesis. In the autumn and winter when the vegetation starts to decompose, coal is again released to the atmosphere and the amount of carbon dioxide once again increases. Each year more coal is released to the atmosphere than can be assimilated during the following vegetation period. Human activity is responsible for this increase and we are increasingly experiencing the ecological and economic consequences. 3

4 The global carbon store is mainly bound in the bedrock, in the oceans and in fossil deposits. There are smaller but important amounts in the atmosphere, vegetation and soil that undergo a continuous exchange. The new situation in the history of the earth is that, during the last hundred years, carbon stored in the soil (the organic humus content), in the vegetation (including forests) and in fossil fuels is decreasing and the atmospheric store of carbon in form of the greenhouse gas carbon dioxide is increasing. Artur.Granstedt@jdb.se 4

5 Soya and other fodder crops are produced for export to agro-industrial countries to feed their fast-growing poultry and pigs. This often results in increasing deforestation and soil degradation in the producing countries. This, along with the combustion of fossil fuel resources, is the main reason for the carbon dioxide increase in the atmosphere. The consequence is not only increasing carbon dioxide levels. Also the capacity to capture the light, assimilate carbon dioxide and produce oxygen for breathing is decreasing. The earth s ecocapacity - to produce and maintain biological diversity, maintain resilience against pests and other stress factors and maintain water storing capacity - is decreasing at the same time as the earth has to carry more people and fill their need of food and water. Artur.Granstedt@jdb.se 5

6 Degradation of soils and the resulting reduction in humus content - a global phenonemon has an impact on the climate and global water holding capacity. This is also taking place in parts of Europe and Sweden in the intensive grainproduction areas. According to FAO/ISRIC 2008/01 (Global Assessment of Land Degradation and Improvement) 20% of the global farm land, 30% of forest land and 10% of pasture land is degraded and has a lower production capacity as a consequence. Artur.Granstedt@jdb.se 6

7 In addition to the increasing emissions of carbon dioxide (CO 2 ), other sources of greenhouse gases include methane gas (CH 4 ) mainly from animal production and dinitrogen oxide (N 2 O) from agriculture, industrial nitrogen fixation and wetlands. Artur.Granstedt@jdb.se 7

8 Agricultural production significantly contributes both directly and indirectly to greenhouse gas emissions: Direct emissions from the use of fossil energy for farm machinery, of dinitrogen oxide (N 2 O) from agricultural land and methane gas (CH 4 ) from animals; and indirect emissions from the use of fossil energy for production of artificial fertilizers, pesticides and imported fodder such as soya and palm oil. The agricultural sector uses more direct and indirect energy (mainly fossil fuels) than it produces in agricultural food products. In addition fossil energy is used in the rest of food chain in food processing industries and transport. Artur.Granstedt@jdb.se 8

9 Swedish Nature Protection Agency calculated in 2008 that the food sector is responsible for 28% of per person greenhouse gases emissions. In addition to that we have the use of private transports, cooking and storing of food in households (part of the travel and housing costs). Including also the climate consequences of deforestation for imported fodder production in total our food system is responsible for about 40 % of the total greenhouse effect derived from human activities. 9

10 This show CO2 tons equivalent per capita and year for some example countries, Bangladesh is example on one of these countries with low own influence on the climate change but will like other lands with large agriculture near sea delta lands become suffer effects of global warming 10

11 Overuse of fossil energy resources has also other consequences. Artificial fixation of nitrogen over load the ecosystems with reactive nitrogen and is together with phosphorus compounds a threat against the Baltic Sea environment. The flow of water into and out of the Baltic Sea is naturally restricted by the islands and narrow channels around Denmark. Coastal areas receive large quantities of nitrogen and phosphorus, mainly from agriculture. Nitrogen and phosphorus are rich nutrients that act as fertilizers, enhancing plant growth. Nitrogen and phosphorus surplus (eutrophication) results in periods with fast growing surface phytoplankton bloom which in this satellite picture is shown as yellow green winding zones on the sea surface here partly hidden by clouds. Concentrations may reach millions of cells per milliliter. This especially applies to algae that experience a significant population increase (so called algal bloom). Dominating species are Aphanizomenon flos-aquae and the poisonous Nodularia spumigena (In Swedish: Katthårsalg). Artur.Granstedt@jdb.se 11

12 When the algae die in autumn their decomposition uses up the dissolved oxygen in the water. The diagram on the left shows how the oxygen content has decreased in Bothnien Sea and Gotlands Deep. When the dissolved oxygen content goes below 0 the deficit favors organisms that release hydrogen sulphide that kills many fish and aquatic organisms. This results in marine dead zones. The area covered by anoxic bottom water appears to be increasing every year. Hydrogen sulphide is now produced in large areas close to 70,000 square kilometers. The Baltic sea is the drainage area for Sweden, Finland, Estonia, Latvia, Lithuania, Poland, and parts of Denmark, Russia and Germany. A total of 85 million people live in this land area of 160 million ha of which 30 million is arable land När algerna dör och bryts ned på hösten förbrukas syre. Diagrammet till vänster visar hur syrehalterna avtagit i Bottehavet och vid Gottlandsdjupet och till höger ses utbredningen. När Syrehalten sjunker under 0 så att underskott uppstår gynnas organismer som avger svavelväte som är giftigt för fiskar och andra syrekrävande vattenorganismer. Östersjöns avvattningsområde omfattar länderna Sverige, Finland, Estland, Lettland, Litauen, Polen, delar av Danmark och en del av Ryssland och Tyskland med totalt 85 millioner människor och en land yta på 160 millioner ha varav 30 miljoner ha är åker. Artur.Granstedt@jdb.se 12

13 Agriculture is responsible for more than 50 % and phosphorus load to the Baltic Sea derived from human activities. Artur.Granstedt@jdb.se 13

14 In Sweden the average use of artificial nitrogen fertilizer increased from 20 to 80 kg per ha and year from 1950 to 1980 (left figure). Today the average input is 110 kg nitrogen per ha including also nitrogen fixation, nitrogen deposition and imported fodder. Agricultural production (in the form of meat, dairy and vegetables products) is only 30 kg nitrogen per ha and year. This difference between input (110kg/ha) and production (30kg/ha) is the surplus that affects the environment. Direct soil leaching makes up approximately a third of this surplus, the rest is released into the atmosphere in the form of ammonium and nitrogen compounds. We shall come back to the reason for this decreasing efficiency and increasing loss of nutrients connected to agricultural industrialization, but first some necessary historical background for a better understanding. This figure with a high increased use of artifizial fertilizers first after 1950 begs an answer to an important question: How could agriculture feed the inhabitants of Sweden before the introduction of artificial fertilizers? The question is even more pertinent if we take into consideration that the inhabitants of Sweden increased from 2 to 7 million before 1950 and that up until this time, before tractors were in common use, agriculture also was producing fodder for the horsepower. Artur.Granstedt@jdb.se 14

15 At the end of 18th century it was not possible to produce enough food for the growing population. The yields were too low on the pastures to feed a sufficient number of animals to produce the amount of manure needed for crop production. Artur.Granstedt@jdb.se 15

16 The high capacity of legumes that in symbiosis with bacteria living in the root nodules fixate atmospheric nitrogen was the biological basis for the agricultural revolution. Such legumes were introduced as an essential part of crop rotations developed in the Nordic countries during the 18th and 19th century. The effect of leguminous plants on soil fertility was well-known already during antiquity and described by Virgilius. A clover grass ley can under the conditions in central Sweden give a yield of 40 tons per ha during one summer. This is equivalent to 7 tons dry matter per ha and based on a nitrogen fixation of 200 kg per ha (Granstedt, 1990). The clover and Luzerne growing 2-3 years in the crop rotation have also deep roots, produce energy rich compounds for the soil microorganisms and act also in symbiosis with special root fungi, mycorrhiza. These factors together stimulate the weathering and uptake of essential macro and micro nutrients from the ground which enter into the soil-crop-animal recycling system Baljväxternas stora kapacitet att genom symbios med baljväxtbakterierna fixera luftkväve möjliggjorde den agrara revolutionen långt innan det fanns någon konstgödsel. Baljväxternas egenskaper var väl kända redan under antiken. En klövervall kan under mellansvenska förhållanden ge en vallskörd på ca 40 ton per ha (7 ton torrsubstans) och binda 200 kg kväve per ha ur luften (Granstedt, 1990). Odlar man bara gräs måste man gödsla med ungefär så mycket konstgödselkväve för att få samma skörd. Förutsättningarna för vallens tillväxt är god övrig näringsämnesförsörjning och som säkerställdes genom att de mesta mineralämnena, särskilt kalium återfördes via stallgödsel och urin från djurhållningen. God vattenförsörjning krävs samtidigt som marken måste vara väldränerad så att det är tillräckligt mycket luft i marken. Artur.Granstedt@jdb.se Fixeringen av luftkväve, till för växten tillgängliga kväveföreningar, är en 16

17 Leys with clover have an effect on the following crop by supplying nutrients both from crop residues plowed into the soil and from the manure from the of the clover grass fed farm animals. This productive clover-ley recycling agriculture was based on each farm s locally available renewable resources. Agriculture was also self-sufficient in traction power and transport - the work-horse, at most , whose feed was also produced on the farm. Artur.Granstedt@jdb.se 17

18 The food crisis at the end of 18th century led to a major agriculture reform that included consolidation of farmland that allowed the introduction of crop rotation with nitrogen-fixing legumes (clover grass land ley 2-3 years), the integration of crop and animal production on the whole farm area (which before was partly separated) and technology improvements to better utilize the natural production potential with help of horse power. This agriculture development had started more than 100 years earlier in parts of Europe and came to Denmark during the 18 th century and finally to Sweden and Finland (Kjaergard, 1994; Granstedt, 1998). At the end of 18th century the arable land only was about 1 million ha and the meadow grassland about three times more. One hundred years later this ratio had been reversed - the plowed arable land was about 3,5 million ha in The cultivated grassland with clover or Luzerne produced about three times more fodder per area unit than the earlier non-fertilized meadow land. More fodder made it possible to keep more animals which in turn gave more animal products and more manure to give higher yields of the cereal crops following the leys in the crop rotation. One important food crop introduced during this period was potatoes a nutrient-demanding crop. The earlier high emigration to America slowed down and Sweden was also able to export food and fodder products at the beginning of 20th century. This time the agriculture produced also the resources for horses used as power for both the agriculture an pars of transports in the society and for the army. Never has Sweden s agricultural productivity based on local renewable resources been so high. Försörjningskrisen kunde mötes genom en kraftig reformering av jordbruket med skiftesreformer så att gårdarna kunde utlokaliseras växtföljdsjordbruk med baljväxter införas. Detta på egna resurser högproduktiva jordbruk utvecklades från den nöd som gällde för delar av den fattigare landsbygdsbefolkningen i slutet av 1700 talet och i början av 1800-talet och som också ledde till en betydande utvandring. Förändringsprocessen började tidigare i andra delar av Europa, kom till Danmark där jordbruket förändrades i grunden under 1700-talet tack vare klöverodling och mångsidiga växtföljder och slutligen till Sverige och något senare till Finland (Kjaergard, 1994; Granstedt, 1998). När förändringarna kom till de Baltiska länderna återstår att studera. Vid slutet av 1700-talet beräknades den plöjda åker till drygt 1 miljon ha medan ängsmarken var nästan tre miljoner ha. Införandet av växtföljder med baljväxtvallar på åker vände på detta, den plöjda åkerarealen ökade på ängsmarkens bekostnad. Den uppodlade arealen var som störst i början av 1900-talet. Skiftesreformerna, bättre redskap, starkare hästar och utdikning av våtmarksängar var viktiga förutsättningar. Den odlade kulturvallen med baljväxter gav flerdubbelt högre skördar än den tidigare ängsvallen, gav mer foder till djuren, ökad produktion av kött och mjölk och samtidigt mera gödsel tillbaka till åkern och som i sin tur möjliggjorde ökad produktion av spannmål och näringskrävande grödor som potatis som tidigare hade stor betydelse för livsmedelsförsörjningen. I början av 1900-talet blev Sverige även exportör av livsmedel och foder. Aldrig har vi haft ett så högproduktivt jordbruk baserat på egna, lokala och förnyelsebara resurser som tiden innan konstgödseln infördes i början på 1900 talet. Jordbruket var då också självförsörjande med sin egen dragkraft hästar vars foder också producerades av detta självförsörjande jordbruk. Artur.Granstedt@jdb.se 18

19 The resource consuming agriculture of to day has characteristics similar to the earlier slash and burn agriculture common in Nordic countries, but nowadays with much higher global consequences. 19

20 The painter Gunnar Brusewitz and the natural geographer Lars Emmelin (1985) documented the landscape and the changes related to the land use and agriculture during the last 300 years illustrated here by a small part of Roslagen in Central Sweden. On the naturally fertile places the first domiciled farm villages were established. Food production was based on the hay making agriculture, pasture land and small lots of arable land fertilized with manure gathered during the winter (meadow is mother of arable land). Artur.Granstedt@jdb.se 20

21 Nature and the landscape are changed by man in order to survive with enough food for more and more people. History teaches us how human beings can in a short period of time deplete the natural resources needed for the future but also how we can refine and improve them. The example documented in this landscape picture demonstrates how this is possible. From the previous old village three farms are now consolidated. On each there is crop rotation with the sustaining clover-grass fields as a part of the rotations and animals whose fodder is produced on the farm and whose manure is returned to the field. Effective use of solar energy, recycling of nutrients and biological diversity were the underlying principles of this agriculture system. These were undermined by the introduction of chemical fertilizers after Människan griper in och förändrar natur och landskap för att klara sin överlevnad på jorden. Historien visar hur vi människor kortsiktigt kan förbruka den resursbas vi skulle behöva för framtiden men också hur vi kan förädla och förkovra densamma. Från den ursprungliga byn ser vi nu efter skiftesdelningen tre gårdar, var och en med sin välväxtföljd i vilken de symbiotiskt kvävefixerande baljväxterna utgör en viktig del. På varje gård fanns djur anpassade till den egna foderproduktionen och vars gödsel och växtnäring återfördes till åkern. Drivkrafterna var de ekologisk grundprinciperna solenergi, kretslopp av näringsämnen och biologisk mångfald och som man nu lärt sig att utnyttja till mänsklig nytta. I början av 1900 talet blev Sverige t.o.m. exportör av foder och livsmedelsprodukter. Detta jordbruk som vuxit fram genom odlingshistorien bröt samman efter 1950 med konstgödselns införande. Artur.Granstedt@jdb.se 21

22 The same landscape 85 years later is totally changed. Farm houses, parts of the arable land, grass lands, divers crop rotations and animals on the fields are gone. Here instead is specialized crop production and the land is now part of a larger farm one result of the comprehensive structural rationalization in Sweden after This change was made possible by the replacement of recycled nutrients via animals and nitrogen fixing crops with artificial fertilizers produced with the help of fossil fuels. Increasing pest and weed problems, a consequence of cereal monocultures and too intensive use of artificial nitrogen for higher yields, were solved through the use of pesticides, the use of which continues to increase today despite stated environmental goals to the contrary. Artur.Granstedt@jdb.se 22

23 Despite of the ambitious and expensive program to reduce nitrogen and phosphorus losses is the surplus and losses on the same level as for 25 years ago (left figure). (75 kg N/ha and year) and also despite an increase of the area ecological production (from ha 1995 to ha 2010). The separation and intensification with more and more of specialized crop farms and more specialized animal farms is the main reason of the on going high input of artificial fertilizers and increased import of fodder. The total leaching of nutrients are still on too high level despite also of the decreasing of the total used arable land (right figure). Approximately 30% of animal feed is now imported in the form of high nitrogen fodder such as Soya protein from tropical countries. 23

24 Specialized crop farms dominate the flat parts of the country. On average 150 kg nitrogen per ha and year is supplied in the form of mainly artificial fertilizers produced with help of fossil energy (about 1 kg oil per kg nitrogen as well as the emission of greenhouse gases) on these farms. The return of this input is on average 100 kg nitrogen in crop products resulting in a surplus lost to the environment of about 50 kg nitrogen per ha and year. The figure is based on statistics from the extension program for nutrient conservation greppa näringen. It is not these type of farms that have the highest loss of nitrogen and phosphorus running out in the Baltic Sea. But it is here that the requirements are created for the high losses because most of this crop production is sold via the fodder industry to specialized animal farms where the high surplus is accumulated and lost to the atmosphere and to water systems instead of being recycled. The specialized crop farm is dependant on the annual input of artificial fertilizers, the macronutrients nitrogen, phosphorus and potassium to compensate the output. An additional problem observed during recent years is the depletion of trace elements in the soil resulting in food crops with poorer nutritional value. The specialized crop farm illustrated here produces mainly grain which is sold via the fodder industry to specialzied animal farms. Artur.Granstedt@jdb.se 24

25 Animal production on the majority of specialized animal farms is two to three times higher than can be based on the farm s own fodder with the consequences that manure production is much higher than can be utilized in farm crop production. Plant nutrients in the animal fodder produced on the specialized crop farms is exported to the increasingly fewer but more intensive animal farms where the surplus is accumulated and finally results in losses to the environment (a linear flow). As mentioned earlier a part of the fodder input is imported from other countries with serious environmental consequences such as deforestation with Soya production and also Palm oil. Animal farms with grassland also buy artificial fertilizers despite a surplus of animal manure. Data from 701 farms in this example from the Swedish extension program greppa näringen showed as average the surplus on this dairy farms 150 kg N and 3 kg P per ha and year and increasing surplus of nitrogen and phosphorus with increased animal density and it is this type of farms which contributes most to agriculture being responsible for a essential part of the nitrogen and phosphorus pollution to the Baltic sea in the countries around the Baltic Sea. Artur.Granstedt@jdb.se 25

26 This figures based also on the data from the refereed extension service program show the relation between animal density in animal units per ha and surplus of nitrogen and also surplus of phosphorus per ha and year. The average surplus on the in the program enclosed ecological farms was lower but on to high level depending also several ecological farms with to high animal density based on fodder from other specialized crop farms and also import of concentrate fodder. Farms with less than 0,6 au per ha adapted to the own fodder production of this category have very low surplus of plant nutrients. 26

27 The linear flows of nutrients in agriculture and the consequences for the Baltic sea can be summarized in these four pictures. Supply of artificial fertilizers to the specialized crop production, transfer of nutrients in the form of fodder from the specialized crop production farms and additional input from imported fodder to the specialized animal production (for example milk, meat, pork, chicken and egg production). The surplus of nutrients here results in the leaching of nitrogen and phosphorus compounds to the Baltic sea especially from the southern part of Sweden which has the highest animal density. This results in phytoplankton blooms and finally a dead sea bottom. The soils in the specialized crop production are depleted of nutrients and humus content is reduced. The combination of use of fossil resources, decreasing soil humus content, deforestation and emission of greenhouse gases is a significant part of the challenge of climate change Skeendet kan sammanfattas i fyra bilder. Vi har ett allt mer linjärt flöde av växtnäring. Tillförsel av handelgödsel till växtodlingen, överföring av växtnäring via både inhemska och importerade foderprodukter till den specialiserade djurhållningen (mjölk-, kött-, fläsk-, fjäderfä- och äggprodukter) och vars växtnäringsöverskott i slutändan bl.a. läcker ut i havet. Linjära flödena av naturresurser istället för kretslopp innebär både att ändliga resurser förbrukas och att miljön skadas. Dagens framställning och användning av konstgödsel innebär att fossila resurser förbrukas och medför miljöskador som drabbar både havet och klimatet. Den ensidiga spannmålsodlingen utan återförsel av allsidigt sammansatt stallgödsel innebär dessutom att odlingsmarken på dessa gårdar utarmas allt mer på de spårämnen som bortförs med grödorna och som inte finns i konstgödseln. Näringsinnehållet av spårämnen i brödsäd från konventionella spannmålsgårdar och i vårt dagliga bröd är i avtagande. Artur.Granstedt@jdb.se 27

28 This figures show preliminary calculation the average surplus per ha and the total surplus for the agriculture in the EU countries around the Baltic Sea calculated for the year 2000 and 2007 based on available data from agricultural statistics. The surplus increased in Estonia, Latvia, Lithuania and Poland and it was a decrease in Denmark from a very high level 28

29 Should the EU states Estonia, Latvia, Lithuania and Poland come up to our levels of nutrient surplus per ha the total load to the Baltic Sea would increase by more than 50% according to several studies. The serious environmental situation and the high risk for an even worse situation has resulted in a comprehensive action programme within HELCOM (Helsinki commission) with commitment from all states around the Baltic Sea to start a action to reduce pollution (Baltic Sea Action Plan). Artur.Granstedt@jdb.se 29

30 In the BERAS (Baltic Ecological Recycling Agriculture and Society) project, which was partly funded by EU, during a three year period the actual situation concerning nutrient conservation in conventional agriculture was compared to the situation on 48 ecological recycling farms. These farms were selected from the 8 countries around the Baltic sea so they were representative of the different agriculture conditions within the Baltic Sea drainage area. Artur.Granstedt@jdb.se 30