Initial effects of forest N, Ca, Mg and B large-scale fertilization on surface water chemistry and leaching from a catchment in central Sweden

Highly increased use of biomass production is placing great demands on Swedish forests. Several silvicultural measures can be implemented to increase forest production and fertilization being addressed in this paper is one. Forest companies are now increasingly applying fertilizer, with the main nutrient needed for high forest growth being nitrogen (N). This study investigated how commercial N fertilization (150 kg N/ha, including also Ca, Mg and B) of the 45 ha forest catchment Risfallet in central Sweden affected chemical composition and runoff export in stream water during one year after the fertilization. This well-defined and long-term monitored catchment proved very suitable for studies of water quality and nutrient losses. The fertilizer consisted of ammonium nitrate (50/50 ammonium and nitrate, respectively), plus calcium (Ca, 22 kg ha (Mg, 12 kg ha boron availability. The study was carried out according to the paired catchment method using a control area and a calibration period. Data from the after treatment period were compared with previous 25-year monitoring data for the catchment and also data for a similar 83 ha control catchment, Gusseltjärn, in the same region. During the first year after treatment, the nitrate concentration in stream water increased from 0.05 mg L ammonium (300%), B (3-fold), Mg (80%), Ca (60%), potassium (K) (50%) and sodium (Na) (40%). The pH decreased in the first half-year by 0.2 pH-units. One year after treatment, 14% of the N applied had leached from the catchment.1) and magnesium1) to mitigate acidification and boron (B 1.1 kg ha1) to compensate for decreased1 to 3.3 mg L1 on average. Other elements showing increased concentrations were ammonium (300%), B (3-fold), Mg (80%), Ca (60%), potassium (K) (50%) and sodium (Na) (40%). The pH decreased in the first half-year by 0.2 pH-units. One year after treatment, 14% of the N applied had leached from the catchment

Duration of forest fertilization effects on streamwater chemistry in a catchment in central Sweden

Demands for forest biomass production for energy, construction and carbon storage purposes are increasing, and therefore measures to increase tree growth are required. One potential measure is nitrogen (N) fertilization, as N is usually the most growth-limiting nutrient in boreal forests and partly due to decreasing atmospheric N deposition in northern Europe in recent decades. However, N fertilization can have adverse effects, such as soil acidification and N leaching, particularly nitrate leaching via streamwater flow. To mitigate the acidification risk, dolomite (CaMg(CO3)2) is added to N fertilizer boron (B) as increased tree growth hamper tree uptake of this essential micronutrient. This study examined the effects of forest fertilization on streamwater chemistry in the 45 ha Swedish catchment Risfallet (RF), around 80% of which was treated with fertilizer. That was rather exceptional, as most previous catchments studied have had <50% treated area, which may give weaker treatment signals. A paired catchment method combined with the control area and calibration period technique was applied to evaluate leaching effects from forest fertilization. Effects over 7.5 years were compared with previously reported initial effects in the first year, in order to assess the duration of fertilization effects on surface water. High excess outflow of N over five years was detected, with 20% of the applied amount leached and with nitrate dominating total nitrogen. Excess outflow of Ca and Mg was highest in the first year. Effects on pH were limited, with calculated untreated pH on 5.9 being on average 0.4 units lower during the first six months and then remaining at 0.2 units lower. Recommended could be to mainly fertilize well-drained soil, avoid wet areas and open streams. Consider the hydrological conditions while weather would be more hazardous to foresee

Deterministic Java in tiny embedded systems

As embedded systems become more and more complex, and the time to market becomes shorter, there is a need in the embedded systems community to find better programming languages that let the programmers develop correct code faster. The programming languages used today, typically C and/or Assemblers, are just too error-prone. The Java technology has therefore gained a lot of interest from developers of embedded systems in the last few years. We propose an approach based on compiling Java into native machine code via C as an intermediate language. The C code generation process should also add close interaction with a fully pre-emptive incremental garbage collector and a small and efficient real time kernel. Tests performed on a small 8-bit microprocessor show that it is possible to use a modern object oriented language with automatic memory management, such as Java, and yet generate fully predictable code that can be run in very small devices with severe memory constraints

Long-term follow-up after comprehensive rehabilitation of persons with epilepsy, with emphasis on participation in employment or education

The objective of this study was to describe the current situation of patients with epilepsy after rehabilitation with emphasis on employment and education and to investigate if clinical factors at admission were associated with increase in employment or education. All patients that participated in a comprehensive rehabilitation were eligible. Data were collected from medical records at admission, during rehabilitation, at discharge and from a structured telephone interview at follow-up 1-17 years after admission. In total, 124 patients participated in the follow-up. Participation in employment or education improved from admission to follow-up in 38 patients. In univariable analysis, active epilepsy with tonic-clonic seizures at admission was significantly associated with increased participation in employment or education at follow-up, so was decreased frequency of tonic-clonic seizures from admission to follow-up. The significance of the associations disappeared in adjusted multivariable analysis. Participation in employment or education was improved for many patients at follow-up.AFA InsuranceAccepte

Växttillgängligt bor i svensk skogsmark

Syftet med projektet ”Växttillgängligt bor i svensk skogsmark” är att öka kännedomen om halten vattenlösligt bor i vår skogsmark, samt redogöra för sambanden mellan denna halt och ståndortsfaktorer, samt andra markkemiska variabler. Utifrån de ca 4000 permanenta provytor inom Riksskogstaxeringen som inventerades av Markinventeringen åren 2000-2002 valdes 210 provytor ut, vilka var fördelade över större delen av Sverige med varierande egenskaper med avseende på ståndort och markkemi. Från Markinventeringens jordprovsarkiv togs delprover ut från lagrade prov från humuslager och B-horisont från de utvalda 210 provytorna. De totalt 420 proven skickades till Eurofins Food & Agro i Lidköping, där de analyserades på växttillgängligt bor med varmvattenextraktion (BHWE). BHWE-halterna i proven från humuslager låg klart över detektionsgränsen (0,10 mg per kg torrsubstans) och medelvärdet (1,39 mg kg-1 ts) låg något över vad som tidigare rapporterats från ett fåtal humusprov i svensk skogsmark, samt klart över genomsnittet för BHWE-halten i matjord från svensk åkermark (0,41 mg kg-1 ts). BHWE-halten i humuslagret var i genomsnitt nästan en tiopotens högre än motsvarande halt i B-horisonten. I proven från B-horisonten låg 30 % av proven under detektionsgränsen. Vid beräkningarna erhöll dessa prov värdet 0,05 mg kg-1 ts för BHWE-halten. Medelvärdet (0,17 mg kg-1 ts) låg i nivå med eller något under vad som tidigare rapporterats för ett fåtal prov från B-horisonter i svensk skogsmark. För hela datamaterialet fanns inget samband mellan BHWE-halten i humuslagret och underliggande B-horisont. Av de många ståndortsvariabler som BHWE-halterna jämfördes med kunde vi för humuslagret bara se signifikanta positiva samband med beståndets ålder och medelhöjd, samt med ökad markfuktighet. För BHWE-halten i B-horisonten noterades däremot flera signifikanta samband med klimat- och ståndortsvariabler, bl.a. minskade halter med främst ökad longitud, men även för ökad latitud och markfuktighet. Signifikant positiva samband fanns mellan BHWE-halten och bl.a. humiditet, ökad deposition, samt marklutning. När det gäller de markkemiska variablerna så fanns det för BHWE-halten i humuslagret signifikanta positiva samband med kol- och kvävehalt, de utbytbara baskatjonerna, titrerbar aciditet, samt katjonbyteskapaciteten. För BHWE-halten i B-horisonten konstaterades signifikanta positiva samband för i stort sett samma markvariabler, men också signifikant negativt samband med pH. De höga halterna av BHWE i humuslagret, samt sambanden mellan BHWE och främst kolhalt och katjonbyteskapacitet och för humuslagret även beståndsålder samt medelhöjd tyder på att tillgången på växttillgängligt bor i marken till stor del styrs av interncirkulation mellan beståndet, förnan och humuslagret. Detta bör man ta hänsyn till vid skogsskötselåtgärder, speciellt vid helträdsavverkning då en stor del av det växttillgängliga borförrådet i ekosystemet kan exporteras från systemet i samband med uttaget av grenar och toppar från det helträdsavverkade området

Millora 2.0: : Redovisning av resultat för 2018 –2022

Based on repeated yearly surveys of the vascular plant flora in 120 hectar plots in the province of Scania, southernmost Sweden, analysed in combination with speciesspecific traits and ecological indicator values (EIVs), changes in the flora and vegetation over the last four years are reported. Many of the changes observed, such as significant increases in lightdemanding, shortlived, pollinatorindependent species with a persistent seed bank, occurred after the extremely hot and dry summer of 2018 but has since then gradually disappeared. However, other changes plausibly also triggered by the extreme summer of 2018 are still evident and may even become persistent, e.g. general increases for species preferring a warmer climate, those with relatively low nitrogen demands and not forming mycorrhiza. Other trends, such as an increase in species richness (similar for both native and nonnative species), and increases for droughttolerant species and species with particularly early or late phenology are evident throughout the study period and are likely reflections of longterm trends driven by changes in land use and climate. Species clearly favored by the drought in 2018 but which has since then gradually dropped back include Galium aparine, Barbarea vulgaris, Bromus hordeaceus, Luzula mutiflora, Phleum pratense, Festuca rubra, Cerastium arvense and Torilis japonica, while e.g. Crepis capillaris, Carex hirta, Jacobaea vulgaris and Veronica serpyllifolia show steadily increasing trends. The only species showing a significant decrease is Sinapis arvensis, possibly being affected by the introduction of new herbicides in the agriculture

Garbage collector interface

The purpose of the presented garbage collector interface is to provide a universal interface for many different implementations of garbage collectors. This is to simplify the integration and exchange of garbage collectors, but also to support incremental, non-conservative, and thread safe implementations. Due to the complexity of the interface, it is aimed at code generators and preprocessors. Experiences from ongoing implementations indicate that the garbage collector interface successfully provides the necessary functionality in an efficient way