A comparison of soil moisture relations between standing and clearfelled plots with burnt and unburnt harvest residue treatments of a clonal eucalypt plantation on the Zululand Coastal Plain, South Africa

The effects of clearfelling and subsequent residue retention or burning on water and nutrient balances needs to be understood and quantified on forest sites that are sensitive to loss, so that the long-term sustainable productivity of such sites can be maintained and promoted. An  experimental site was established in a clonal eucalypt compartment on the Zululand Coastal Plain, to compare changes in water fluxes through the mature undisturbed eucalypt stand with those after felling and re-planting, under 2 conditions: burning, and retention of the harvesting residues. The study was located in an area of high rainfall and high stand productivity, with sandy soils and low soil carbon and nutrient status; chosen so that the effects of intensive demands on water and nutrient fluxes on a potentially sensitive site could be investigated. This paper presents only the hydrological component of the study. Data collection included weekly determination of rainfall, throughfall, stemflow and soil moisture fluxes from the surface to a depth of 1 m. Drainage rates through the profile were established using time domain reflectometry probes while water drainage volumes were assessed using shallow plate lysimeters. Despite slow growth in the unfelled crop during the monitoring period (attributed to a pest infestation), soil moisture depletion remained rapid and drainage below 1 m remained low. Soil moisture was recharged within a few months after clearfelling, but became rapidly depleted as the canopy of new crop developed and approached canopy closure. A decreased wetting-front velocity and a marginally higher field capacity were proposed as evidence of pore clogging that appeared to occur during the inter-rotation period. The soil profile under the unburnt residue maintained a marginally higher soil moisture status and lower drainage than the soil profile under the burnt residue. Although soil moisture and drainage in the burnt and unburnt residue treatments became similar to the unfelled crop from canopy closure onwards, rainfall additions to soil moisture were depleted faster under the new crop during the first few months after canopy closure. Small differences in soil moisture status between the burnt and unburnt residue treatments presented here may not be sufficient to influence residue management decisions. The length of the inter-rotation period and practice of residue burning may, however, need consideration where soil carbon and nutrient loss or displacement may negatively affect the sustainability of the site.Keywords: Soil moisture drainage, residue burning, post felling, inter-rotatio

The Synthesis and Antiviral Properties of 8- Amino-3- [(2 hydroxyethoxy)methyl]-1,2,4-triazolo- [4,3-a ]pyrazine

The preparation of 8-amino-3-[(2-hydroxyethoxy)methyl]-1,2,4- triazolo[4,3-a]pyrazine (IV) as an analogue of 9-[(2-hydroxyethoxy) methyl]guanine and 9-(S)-(2,3-dihydroxypropyl)adenine is described from the reaction of 3-chloro-2-hydrazinopyrazine (V) and ethyl 2-(2-acetoxyethoxy)thioacetimidate (IXg) followed by treatment with ammonia. Compound IV was found to lack antiviral properties towards herpes simplex I and II, vaccinia virus, vesicular stomatitis virus, measles, reovirus type 1, parainfluenza virus type 3, Sindbis virus, Coxsackie type B4 virus, and poliovirus type

De Noordzee: een waardevol archief onder water. Meer dan 100 jaar onderzoek van strandvondsten en vondsten uit zee in België: een overzicht

De Noordzee kan beschouwd worden als een waardevol en speciaal archief, met heel wat interessante informatie over het verleden. De zone beneden de laagwaterlijn behoort tot het domein van de subtidale archeologie of de archeologie van het subgetijdengebied van de Noordzee. De zone tussen de hoog- en de laagwaterlijn behoort tot de intertidale archeologie of de archeologie van het intergetijdengebied van de Noordzee. In het eerste deel van deze studie wordt kort de geschiedenis van het onderzoek in deze beide zones geschetst. Daarna wordt in een tweede deel een chronologisch overzicht gegeven van de resultaten van het onderzoek en dit vanaf het ontstaan van de archeologie als wetenschappelijke discipline. In dit tweede deel wordt ook een klein aantal tot nu toe ongepubliceerde vondsten opgenomen van buiten het Belgische deel van de Noordzee. De reden hiervoor is zowel pragmatisch als inhoudelijk. Enerzijds worden deze vondsten geregistreerd samen met de andere vondsten, ze bevinden zich immers samen in de bestudeerde collecties. Anderzijds dragen ze ook inhoudelijk bij tot een beter inzicht in de genese van het hele zuidelijke Noordzeegebied, waarvan de zone onder Belgisch toezicht deel uitmaakt. Verder dienen in dit tweede deel ook een aantal vraagstellingen en onderzoeksstrategieën als basis voor de globale discussie in het derde deel van deze bijdrage. De bijdrage wordt ten slotte afgesloten met een zo volledig mogelijke bibliografie over het onderzoek in het Belgische deel van de Noordzee inclusief de stranden

<Session 3: Biomedical Technology>Assessing radio frequency electromagnetic field exposure with a wearable network of dosimeters

19–22 May 2022 Kyoto, JapanIn contrast to the tremendous increase of wireless applications, the knowledge about daily life radio frequency electromagnetic field (RF-EMF) exposure remains low. Some research has already been conducted using large commercial single-antenna on-body dosimeters to assess daily RF-EMF exposure in different environments. To increase measurement quality and decrease variability however, a distributed, wearable body sensor network spread over the body for the assessment of RF-EMF exposure is desired. As a better alternative to the common single node assessment technique, this work therefore presents a wearable sensor network consisting of five nodes for the assessment of exposure in the 389 to 464, 779 to 950 and 2400 to 2483.5MHz bands using only two transceivers per node. A single node supports an antenna connection for the first band, two for the second and two for the third band. This makes antenna diversity possible and hence increases sensitivity for specific frequencies, depending on the choice of antenna design. Every node is powered by two AAA batteries, which define the size of the system (53x25x15mm), making it smaller than any other commercially available dosimeter. Furthermore, the device supports an inertial sensor for the assessment of body posture and/or activity during the measurement