Mari Tilk

Short-Term Influence of Clinker Dust and Wood Ash on Macronutrients and Growth in Norway Spruce (Picea abies) and Scots Pine (Pinus sylvestris) Seedlings

The effects of clinker dust and wood ash on Norway spruce and Scots pine seedlings were compared in buried pots. Clinker dust (0.5 kg m−2) and wood ash (0.5 kg m−2) were applied to the surface of a nutrient-poor mineral soil. In the second year, the increase in soil pH by the dust and ash were larger than in the first year. Both alkaline treatments caused a large increase in the needle potassium (K) concentration. An excess of soil K relative to magnesium (Mg) was observed by decreased Mg concentration in needles shortly after treatment. However, Mg concentration in needles stayed in the sufficiency range. Current results confirmed earlier findings that despite a positive effect on base cation nutrition, wood ash has a low potential for increasing the biomass of forest stands on mineral soils due to the N limitation in these soils.

Chemical characteristics of soils in Scots pine forests of Cladina and Vaccinium vitis-idaea site types on coastal dunes of Baltic Sea

Chemical characteristics of soils in Scots pine forests of Cladina and Vaccinium vitis-idaea site types on coastal dunes of Baltic Sea The coastal dunes of Southwest Estonia have been undergoing a process of stabilisation and are today covered predominantly with Scots pine forests. For the investigation of soils on dunes sampling sites were selected according to topographical positions and forest site types: two sites in Cladina and two sites in Vaccinium vitis-idaea site types on dunes of different heights. The prevailing soils on dunes are Gleyic Podzols, which are generally poor in humus, water and mineral nutrients. Great differences in soil chemical components were found on the foots, slopes and tops of the dunes depending on the height of the dune. The study showed that the concentration of macronutrients (N, K, Ca, Mg) in soil decreased from the foot towards the top. On the other hand, a serious decrease in the nutrient concentration from the O horizon to the BC horizon was typical of the dunes. The soils were generally acidic, with the pH of 3.4-5.5 in the studied sampling sites. The soils were more acidic on the foots of the dune and in the O and A horizons. Mulla iseärasused luitemännikutes Cladina ja Vaccinium vitis-ideae kasvukohatüübis Edela-Eesti rannikumaastikule on iseloomulikud pärast viimast jääaega jääliustiku sulamise setetest moodustunud luited ja rannavallid. Luitemaa looduskaitseala on loodud Antsülusjärve ja Litoriinamere rannaluidete ja nende ümber kujunenud koosluste, aga ka rannaniitude ning ohustatud ja haruldaste liikide elupaikade kaitseks. Luidetel on kujunenud omapärane mullastik ja universaalsed taimekooslused. Käesoleva töö eesmärgiks on anda uusi teadmisi luidete mullahorisontidest ja toitainete sisaldusest seotuna luite kõrguse ja prooviala asukohaga ning põhitähelepanu oli pööratud muldadele Cladina ja Vaccinium vitis-ideae kasvukohatüüpides. Rannametsa piirkonnas valiti 4 luidet, igal luitel 3 proovipunkti: jalamil, nõlva keskosas ja luite harjal. Kaks prooviala (kõrgustega 34 ja 27 m ü.m.p.) asuvad Vaccinium vitis-ideae ja kaks (14 ja 9 meetrit ü.m.p.) Cladina kasvukohatüübis. Proovipunktides määrati erinevad mullahorisondid ja nende tüsedus, igast horisondist võeti proovid pH ja makrotoitainete määramiseks. Luitemuldadele on iseloomulik õhuke huumushorisont (A), mida võis leida ainult luidete jalamil paiknevates proovipunktides, horisondi tüsedus varieerus 2-20 sentimeetrini. Kõduhorisont (O) oli õhuke, vähenedes 4-30 sentimeetrilt luite jalamil 5-10 sentimeetrini luite harjal. Tulemustes ilmnesid olulised erinevused luite jalami, nõlva keskosa ja luite harja mullaproovide keemilises koostises sõltuvalt luite kõrgusest. N, K, Ca ja Mg sisaldus väheneb oluliselt liikudes luite jalamilt harjale. Samuti on luidetele iseloomulik toitainete kontsentratsiooni vähenemine O horisondist BC horisondini. Mullad on tavaliselt happelised (pH 3,4-5,5), kusjuures happelisemad on jalamil paiknevate proovipunktide mullad ning O ja A horisondid.

Morphometric parameters of pine needles in Tolkuse bog in the dune field in Southwest Estonia.

Männiokaste morfomeetriast Edela-Eesti luitemaastikku ilmestavas Tolkuse rabas Needle characteristics of Scots pines (Pinus sylvestris L.) in Tolkuse bog (SW Estonia) their length, dry weight and area are discussed. Samples of needles and peat were collected from seven small forest stands in Tolkuse bog in summer 2004. The sampling sites were selected from transect across the bog margin towards its centre (site I - bog margin, site VII - bog centre). Sample branches (n = 30) were collected from the southern sides of the crowns of three trees at heights of 1.5 and 3.0 m. Soil analysis of the samples showed that the pH of peat in Tolkuse bog was in the range 3.3-4.2. The nutrient concentrations of Tolkuse bog peat (% of dry mass) varied as follows: total N 0.7-1.5, total P 0.07-0.14, total K 0.02-0.06, Ca 0.14-0.51 and Mg 0.06-0.22. As compared with other sampling sites a significantly higher concentration of nutrients was observed in the peat at site V. This may explain the best growth of the needles at this site. Site VII, located in the centre of the bog between hollows where bog water is closest to the surface, had the smallest measurements of needles. This indicates that this site has the least favourable conditions for pine growth. Needles growing in the crown at a height of 3 m from the ground had a considerably smaller needle area than those at a height of 1.5 m from the ground. Morphometric parameters of pine needles in Tolkuse bog in the dune field in Southwest Estonia Although in Estonia bog forests are ancient biotopes relatively little affected by human activity so far, the ever-intensifying anthropogenic impacts are beginning to threaten also the existence of bogs. In the Baltic States Tolkuse bog is the only bog with a peripherally oligotrophic development path whose central part has better nutrition conditions than its peripheral parts. In the course of the project changes in the length, dry mass and area of the needles of bog pines were studied moving from the margin of the bog towards its centre. Comparison of the concentrations of N, P, K, Ca and Mg in the upper peat layers in Tolkuse bog with the respective average concentrations in raised bogs, transitional bogs and moorlands revealed that Tolkuse bog was poorer in Ca and also N and P. Site V had significantly higher N, P and Ca concentrations than the other sampling sites. The height growth of 60-90-year-old bog pines was 5,6 ± 1,1 m and diameter 14,2 ± 4,1 cm. The pines of site I had the longest needles (in the crown at a height of 1.5 m from ground on average 3.7 cm and at 3 m 4.1 cm). This shows that marginal areas of the bog have the best conditions for pine growth. The shortest needles were observed in pines growing on site VII (on average 2.7-3.0 cm). This area is located in the centre of the bog and is surrounded by hollows. The average dry mass of a pine needle at a height of 1.5 m from ground was 0.006-002 g and at a height of 3 m, 0.008-0.01 g. Similarly to needle mass, the needle area was largest in site V, located at a somewhat higher position on a bog islet and having higher concentrations of nutrients in peat than other sites. It is important is to preserve the diverse and peculiar bog pine forests in Estonian scenery. In other European countries such forests have preserved only fragmentarily due to intensive human activity. Therefore it is absolutely necessary to continue the monitoring of the status of Estonian bogs and ecological investigations to get information on future trends.

Drought tolerance of Scots pine in diverse growth conditions on a dune estimated on the basis of carbohydrates and chlorophyll fluorescence in needles

Drought tolerance of Scots pine in diverse growth conditions on a dune estimated on the basis of carbohydrates and chlorophyll fluorescence in needles Variation in the needle carbohydrate concentrations in Scots pine along the height profile on a forested dune in south-western Estonia were measured in spring. To assess the tolerance of trees, carbohydrate concentrations were compared with shoot morphology and photosystem II quantum efficiency (chlorophyll fluorescence). To test a potential effect of drought events on trees, chlorophyll fluorescence was measured in needles after drying and recovery, and dependcies of the treatment effects on the location on the dune were looked for. Water concentration in detached needles was reduced by a partial drying in laboratory. Needles were recovered by an addition of water. Carbohydrate concentrations were rather constant irrespective of shoot morphology and the tree location on the dune. The reduction in the photosynthetic efficiency, observed after the treatment, depended on the site. The results indicated that trees growing at lowest relative heights on the dune were potentially more vulnerable to drought than other trees on the dune at relative height of 5 to 25 m. Hariliku männi põuataluvus mitmekesistes kasvutingimustes luitel hinnatuna okaste süsivesikute sisalduse ning klorofülli fluorestsentsi järgi Süsivesikute sisaldus erinevused männiokastes olid väikesed, kuigi keskkonnatingimused ja puistu tihedus varieeruvad luitel oluliselt. Püstitati hüpotees, et puistu arengu jooksul süsivesikute moodustumine puudes ja kasutamine kasvuks ning mullaprotsessides tasakaalustuvad. Arvatavasti on luite tipus esinev vee ja mineraalainete raskendatud omastamine tasakaalustatud soodsate valgustingimuste poolt. Süsivesikute sisaldus okastes ja võrsete morfomeetrilised näitajad korreleerusid. Tärklise ja sahharoosi sisaldus oli suurem võrsetes ja okastes, millel oli suurem kuivmass. Fotosüsteem II kasuteguri analüüs klorofülli fluorestsentsi (Genty parameetri) järgi näitas, et vähene sademete hulk maikuus ei põhjusta puudel stressi. Täiendav okaste kuivatamine laboritingimustes suurendas erinevusi Genty parameetri osas. Tulemuste põhjal oletati, et luite kõrgematel kohtadel paiknevad puud taluvad põuda paremini kui puud, mis asuvad luite jalamil. Siiski on klorofülli fluorestsentsi analüüsi ja okaste laboratoorse töötlemise metoodikat vaja edasi arendada, kuna okaste kuivamine sõltus proovi massist. Täpsemate meetodite juures peab säilima praeguse metoodika kasutamise lihtsus ja analüüsikiirus.

Afforestation of cutaway peatlands: effect of wood ash on biomass formation and carbon balance

Abstract Alternatives to the restoration of cutaway peatlands include afforestation, energy forests, agricultural production, wetland restoration (restoration of peataccumulating function), reed canary grass (energy mower) or wild berries (blueberry, cranberry) cultivation, protected area for birds, and artificial lakes. Investigations made in several countries suggest that one of the most promising ways of regenerating cutaway peatlands is afforestation. The re-vegetation of Estonian cutaway peat production fields is mainly the result of natural processes, which are generally very slow: vegetation covers only 10–20% of a peat field. Carbon dioxide is not bound anymore in cutaway peatlands where vegetation layer has been destroyed and therefore photosynthetical processes no more occur. Using biofuel ashes (wood ash, etc.) for the afforestation of cutaway peatlands helps to balance the content of nutrients in peat substrate, which improves the survival of planted seedlings and significantly increases bioproduction. Drained and mined peatlands have become a significant source of CO2 but stimulated woody biomass production can be helpful to balance CO2 emission from cutaway peatlands. Because of the limited resources of fossil fuels and negative impacts on the environment in recent decades alternative sources of energy have been actively looked for. In Scandinavia a lot of attention has been paid to finding possibilities for using biofuels. The situation in Estonia is that only very few types of ashes (for example certified oil shale fly ash with product name Enefix) have been founded to be suitable for utilization and have been used for recycling in agriculture.