 Thank you for coming so early for my talk. It's a nice surprise to see so many people and I'll present the results of our about three or four year hunt for features of slash and burn cultivation and Probably, you know better than maybe to say I'm a soil scientist what slash and burn cultivation is about but just a short summary Sweden agriculture is a type of farming and fields are Burrent cropped for short periods of time and then abandoned for a forest fellow in there are many types of Sweden agriculture, but Forest Sweden's or forest less and burn cultivation is central Purpose of burning is Land clearance preparation of seed bed Release of nutrients and that's very important for poor sandy soils or stony soils And elimination of weeds It's believed that slash and burn cultivation was practiced at least since the bronze age But became much more common in the early average with them advent of iron implements Until recently until 20s mid 20th century Slash and burn cultivation still existed in northern countries with poor soils such as Scandinavia and Northern northern Russia Let's still exist and it emerges every time when people are in poverty and there is forest under him to burn and clear for other culture They are very good descriptions of Recent and northern types of Swedens or Sweden technologies Compiled by Petrov and published in Russian, so not many people actually read it, but it's a it's a very Important source of information because he used all available sources of information so What would be the central or main part of them? slash and burn Technology or take a session burn approach to forest clearance would be a small size of the field Preparation of trees for falling by your link trees filling formation of fuel bed when The whole tree often with roots is placed on the ground then burning either in spring for Summer crops or in summer for full full crops then sewing In warm ashes and ashes are central for this technique and Then harvesting for one to three years Common crops are not necessarily Serialists, but also pulses turnip And even goose food a quinoa podium The short cropping period is followed by abandonment and forest fallow for several decades Usually just a second and usually saying this was a preferred for Sweden agriculture for many reasons But first of all is warmer and the vegetation period is much longer on sandy soils So even so we have good descriptions of slash and burn cultivation morphology soil morphological features of Desperate techniques or that should should result from this farm and technique are unknown and it's amazing because Presumably there should be everywhere at least on sandy soils because we believe that swing cultivation was quite ubiquitous on poor soils infertile soils so if We hypothesized what morphological features should be typical for sweden soils with sort of High mode of charcoal and ash combustion products in the Sweden layer and Ash consists of carbonates and phytol is so once the carbonates are removed from the profile in course of several years there still should be a significant amount of plant opal or phytol is and Because they are tiny of silt size Then we assume that there will be increased in the silt fraction in the soil Then because the Debris are raked or spread on the surface there should be diminution of charcoal. So it should be small but evenly distributed within the sweden layers Then because ash is alkaline there would be a peak even for short term maybe but picking alkalinity and picking erosion so this Ash in mud slurry would be moving along the surface Re-depositing transport and re-depositing the combustion degrees and Finally because it's a small opening the forest it should be forested quite rapidly so if we Think of Philharmonical signatures of Sweden it would be very similar to us to a small scale forest fire And when we worked on archaeological sites and we have a long-term project in Tatarstan and vulgar area we found a number of Sites with soils that agreed with our assumptions Should be in Sweden soils, but it's always good to have Sites where students are documented and it was a very lucky coincidence that We met with his pillow Thompson who discovered documented Sweden areas in Estonia that were Affected by slush and burn cultivation in 19th century, so we used the sites to Check whether really the features that we expected a source to have are there so the study area was in correlation Park Estonia and Here are the maps that Philly found in archives And you can see that pink areas on the map are marked as bushlands and Bushlands are not called so not because they're covered by bushes, but because the trees that grow there Are not allowed to mature. They are repeatedly cut at the young age And converted into Swedens, so it's amazing that in Estonia where some Permanent fields exist for thousands of years. They coexisted with swedens on Nobs on hilly areas so we analyzed several sites and There are sites that Were affected by experimental swedens Sites that are documented as swedens and located now in the forest and Forest sites that are like affected by wildfire because it's essential to Find the distinctive features of both natural fires in Sweden's and here are three typical pictures that We encountered so On the left it's a plow land that was Used in the experimental Sweden, so the very top five to seven centimeters are darkened by charcoal on the right The top photo Depicts the result of the forest fire and it's a typical cinder gray color clusters of charcoal clusters of large fragments of charcoal and The lower boundary is not as even as in the plow soil but rather Reflects a lateral movement of materials in suspensions along the surface On the lower right You can see actually the portray of the swim cultivation and the lower boundary is not even Also, it doesn't show lamination typical for the lateral movement of suspensions, but it has very typical traces of insects and Such high density of traces of insects in the knifers courses Highland usual this finger like boroughs construction are constructions of so-called sweat bees of digging bees and This dig in bees that create this finger like pattern are known for being main pollinators of non-serial groups such as turning for example peppers in South America Or whatever you can pour beads in soil So We traced this Dark colored layers with scallop lower boundary in a number of sites and they have specific Color code according to Munsell the thickness is varying from five to ten centimeters a medium thickness of seven centimeters and Even the color and lower boundary is quite is quite diagnostic of this swings Moreover in the lower parts of slopes There are numerous Sweden layers, so they are stuck and we could see up to four layers of swings in the same profile so if beside the macro features their Mesa features of Swedens and they are a huge proportion of vital is up to 200 of up to 200,000 of of Vitalist program of soil and an enormous amount of charcoal every gram of soil has at least one fragment of charcoal of a typical size that is about a median has about five millimeters So if we imagine what this soil surface looks like after the burn is ash and In this ashes slurry when charcoal is moving laterally it gets rounded so it The ash and silt form coating on the surface of the charcoal, and it looks it almost Doesn't look like And it's quite important because this time capsules Can be also covered by iron deposits and be preserved for hundreds and thousands of years, and they are datable so we can try to cover date them and Know when exactly the Sweden was formed Finally, there are different types of fuels in the Swedens and in forest fires if for forest fires It's typically a huge for high proportion of bark in the charcoal assemblages. Where as in the Swedens, there are always components of the canopy either buds or needles and Finally the composition of charcoal in Swedens Usually shows a high proportion of deciduous taxa and they're not burned easily during the fires and Just to show you that once we know what the Sweden looks like We can just look at the photos and say it's it's a portrayal Sweden and retrospectively we looked at the sites where we worked in the past and we could Create maps or sites affected by Sweden and some of them are Dated others can be dated because once we know that it's Sweden we can easily obtain radiocarbon dates, but Finally because we know what it looks like even Express tasting with a soil auger can show you How many Sweden layers are at the base of the slope and we can Delineate the contrast of the Swedish. Thank you