Location and interpretation of post-forest-fire sediments – case studies

Forest fires are common phenomenon in many countries, including Poland. Forest divisions are the institutions responsible for their monitoring and control. Their task is to detect, fight and counteract the fire forest effects. For a long time forest divisions have maintained the database of forest fires, since 2010 in digital version (Information System of the State Forests – SILP, Llas.2). The information gathered in SILP includes the classification, size and location of fires. The Information for the years 2010–2014 was obtained from the Forest Division Suchedniów (Świętokrzyskie province). Most fires were small, often limited to undergrowth and soil cover (less than 1 ha), two of them were classified as medium-size fires (over 1 ha). In post-fire areas a series of shallow geological borings was made. In most profiles no fire traces (layers of charcoal, individual coals etc.) where found. Such traces were preserved on flood plains, under the edges of terraces, where post-fire layer was covered by colluvial deposits. The study of forest soil pH indicate that fires which occurred many years ago did not leave any significant changes in the pH level, while in fire areas several years old pH level was lower. The results of contemporary post-fire sediments studys may be helpful in paleogeographical and geoarchaeological reconstructions (e.g. O’Connor, Evans 2005). In geological profiles it is common to find single charcoals, rarely layers. Their presence, changing the amount of sediment raises a number of controversies and problems with interpretation. In the Druć River valley (Belarus) the layer (0.2–0.35 cm) of post-fire charcoal (14C dating: younger than 200 years old) is covered with sandy colluvia (thickness 30 cm) with numerous of Neolithic and Iron Age artifacts. In this case the thickness of post-fire sediment many times exceeds sediments observed in Suchedniów Forest District, and suggests the occurrence of a very large forest fire (probably anthropogenic). After the fire, intensive soil erosion began in the burnt area, which in a short time covered fossilized charcoals layer by colluvium containing the artifacts.Pożary lasów są częstym zjawiskiem w wielu krajach, w tym i w Polsce. Instytucjami odpowiedzialnymi za ich monitorowanie i kontrolę są nadleśnictwa. Ich zadaniem jest wykrycie oraz przeciwdziałanie skutkom pożaru lasu. Nadleśnictwa prowadzą od dłuższego czasu, od 2010 roku w formie cyfrowej (System Informacji Lasów Państwowych – SILP, Llas.2), bazy danych dotyczące klasyfikacji, wielkości i lokalizacji pożarów lasów. Informacje za lata 2010–2014 pozyskano z Nadleśnictwa Suchedniów (woj. świętokrzyskie). Przeważnie pożary były małe, często ograniczone do podszycia i pokrywy glebowej (poniżej 1 ha), dwa z nich zostały sklasyfikowane jako pożary średnie (ponad 1 ha). Na terenach popożarowych wykonano szereg płytkich wierceń geologicznych. W większości profili nie odnotowano żadnych śladów po pożarach (warstw węgla, pojedynczych węgli etc.). Takie ślady zachowały się na terenach zalewowych, pod krawędziami teras, gdzie warstwa po pożarze była przykryta deluwiami. Badania pH gleby leśnej wskazują na to, że pożary sprzed wielu lat nie pozostawiły żadnych znaczących zmian w poziomie pH, natomiast w miejscach, gdzie pożary miały miejsce kilka lat temu poziom pH był niższy. Wyniki badań współczesnych warstw pożarowych mogą być pomocne w paleogeograficznych i geoarcheologicznych rekonstrukcjach (np. O’Connor, Evans 2005). W profilach geologicznych powszechne są pojedyncze węgle, rzadziej warstwy. Ich obecność, zmienna ilość osadów budzi jednak szereg kontrowersji i problemów interpretacyjnych. Przykładem może być stanowisko w dolinie Druci (Białoruś), gdzie warstwa (0,2–0,35 cm) węgli popożarowych (datowanie 14C – osady młodsze niż 200 lat) jest przykryta piaszczystymi deluwiami (grubość 30 cm) z licznymi artefaktami neolitycznymi i z epoki żelaza. W tym przypadku miąższość warstwy pożarowej wielokrotnie przewyższa osady obserwowane na terenie Nadleśnictwa Suchedniów, sugerując wystąpienie bardzo dużego pożaru lasu (prawdopodobnie antropogenicznego). Po pożarze, na odsłoniętej powierzchni, doszło do intensywnej erozji gleby, co doprowadziło w krótkim czasie do przykrycia warstwy węgla przez deluwia zawierające redeponowane artefakty

Secular and catastrophic processes reflected in sediments of the Suchedniów water reservoir, Holy Cross Mountains (Poland)

The Suchedniów water reservoir is located in the central section of the River Kamionka in the northern part of the Holy Cross Mountains of central Poland. This area once belonged to the Old Polish Industrial District that, during the Middle Ages, was very intensively developed by iron metallurgy. Many forges and mills along the rivers used water power, which led to the construction of an anthropogenic, small-scale water retention system. At the beginning of the twentieth century many of these reservoirs were drained after the collapse of metallurgical activities. The present-day reservoir was built in 1974 and drained in 2017. Research into the drained basin has documented various forms and sediments, some of which record present-day depositional processes (fire proof clay layer, inland fan delta), while others represent the historical period (lacustrine sediments of older reservoirs). Traces of catastrophic events have been preserved as well; an assemblage of megaripples marks the sudden drainage caused by a dam break in 1974

Excavation along the easternmost frontier of the LBK in NE-Hungary at Apc-Berekalja I (2008–2009)

The topographical position and size of the site, the number of detected houses, the presence of the early phase make the Apc-Berekalja I settlement one of the most significant sites of the LBK in Hungary. The ongoing processing of the excavation data provided already some very important observations. The geoarchaeological results demonstrated the presence of the in situ soil of the Neolithic period and effects of floods on the settlement. The study of the chipped and ground stone material coming from the Neolithic features revealed no conspicuous changes in the lithic industry of the settlement from the pre-Notenkopf to Želiezovce phases of the LBK. Lithic raw materials came exclusively from territories to the east of the site, which is an evidence of the isolation of the LBK groups that inhabited Apc. | Földrajzi helyzete, a lelőhely mérete, a megfigyelt házak száma és a korai fázis megléte alapján Apc-Berekalja I. az egyik legjelentősebb magyarországi VK-település. Az ásatási adatok még folyamatban lévő feldolgozása során közlésre méltó eredmények születtek. A geoarcheológiai vizsgálatok kimutatták egy neolitikus korú talaj in situ meglétét, valamint a települést sújtó áradásokat. A neolitikus korú objektumokból származó pattintott és szerszámkövek a település fennállása alatt a kőipar lényegi változatlanságáról tanúskodnak a VK korai időszakától a zselízi fázisáig. A településen élők a kőnyersanyagokat kizárólag a keletre eső területekről szerezték be, ami az itt lakó csoport izoláltságát igazolja

Morphology and sediments of flash flood near Kromołów (southern Poland) after 20 years

The examined area is located in southern Poland on Silesian Upland. According to geomorphologic regionalization, it is southernmost part of Valley of Upper Warta and Prosna Rivers between two cuestas – Upper Jurassic in the east and Upper Triassic in the west. There is northern Upper Silesia Region near spring of Warta River, tributary of Oder River. Some dry, fluvio-denudational valley (trough, dellen) form drainage pattern around Kromołów, which is a district of Zawiercie city. These dellen, which have been formed in periglacial conditions of the Pleistocene, are relict forms very typical for Polish Uplands (Fig. 1, 2). These Pleistocene valleys were rejuvenated during the Holocene. Good example of this type of relief transformation is a small dry valley located near center of the Kromołów. The first-phase of headward erosion reached upper section of the valley in the Subatlantic Large scale of soil erosion is confirmed by thick (about 3 m) series of deposits with fragments of 17-18 c. pottery accumulated in the middle section of the valley. The erosion cut in middle section has a depth of 3-4 meters and a length of almost 800 meters. This accumulation and incision was associated with flash floods which were main morphogenetic factor of transformation of this valley type during the Holocene. A scale of erosion-accumulation processes during catastrophic event was showed by last flash flood in 1996. Few profiles located in this valley, give us information about accumulation during one event. Alluvia (thickness 2.5 m) were deposited in two phases in middle section of the valley (Kromołów KR 4 profile) (Fig. 4, 5, 6). Two sediment members are separated by thin layer with plastic garbage. Lower member consists of sand mixed with detritus and coal. After almost twenty years forms and sediments of these floods are preserved only in the middle section of the eastern valley. Hydro-technical constructions (dam, reservoirs) built in the northern valley only partially protect Kromołów against further flash flood events

Secular and catastrophic processes reflected in sediments of the Suchedniów water reservoir, Holy Cross Mountains (Poland)

The Suchedniów water reservoir is located in the central section of the River Kamionka in the northern part of the Holy Cross Mountains of central Poland. This area once belonged to the Old Polish Industrial District that, during the Middle Ages, was very intensively developed by iron metallurgy. Many forges and mills along the rivers used water power, which led to the construction of an anthropogenic, small-scale water retention system. At the beginning of the twentieth century many of these reservoirs were drained after the collapse of metallurgical activities. The present-day reservoir was built in 1974 and drained in 2017. Research into the drained basin has documented various forms and sediments, some of which record present-day depositional processes (fire proof clay layer, inland fan delta), while others represent the historical period (lacustrine sediments of older reservoirs). Traces of catastrophic events have been preserved as well; an assemblage of megaripples marks the sudden drainage caused by a dam break in 1974

Secular and catastrophic processes reflected in sediments of the Suchedniów water reservoir, Holy Cross Mountains (Poland)

The Suchedniów water reservoir is located in the central section of the River Kamionka in the northern part of the Holy Cross Mountains of central Poland. This area once belonged to the Old Polish Industrial District that, during the Middle Ages, was very intensively developed by iron metallurgy. Many forges and mills along the rivers used water power, which led to the construction of an anthropogenic, small-scale water retention system. At the beginning of the twentieth century many of these reservoirs were drained after the collapse of metallurgical activities. The present-day reservoir was built in 1974 and drained in 2017. Research into the drained basin has documented various forms and sediments, some of which record present-day depositional processes (fire proof clay layer, inland fan delta), while others represent the historical period (lacustrine sediments of older reservoirs). Traces of catastrophic events have been preserved as well; an assemblage of megaripples marks the sudden drainage caused by a dam break in 1974