A new concept for the control of Elytrigia repens in organic crop production

The control of perennial weeds in organic crop production needs reconsideration to minimise losses of nutrients through leaching. Long post-harvest periods with mechanical weed control hinder a plant cover with the purpose of taking up nutrients not being utilised by the main crop to maintain soil fertility. To meet the interests of nutrient and weed management, we suggest a new concept for the control of perennial weeds with propagules placed within the plough layer. The concept comprises uprooting and immediate removal of Elytrigia repens rhizomes with modified machinery to allow for a quick re-establishment of a plant cover to avoid longer periods of bare soil. Four passes with a modified cultivator where each pass was followed by rhizome removal and finally catch crop growing reduced E. repens shoot growth in a subsequent spring barley crop by 84 and 97%, respectively, in two field experiments on a sandy soil. Small remains of rhizomes in the soil following uprooting did not result in a higher shoot production rate than larger residuals as otherwise hypothesised. For the further development of the concept, we suggest focusing on lifting principles known from potato harvesters as effective uprooting and removal might be achieved with fewer passes

Ny tørringsteknik kan gøre økologisk korn bedre

Økologisk dyrket korn lader til at være mere udsat for angreb af svampe og toksiner end det konventionelt dyrkede. Tromletørring af kornet ved bestemte temperaturer kan være en løsning på problemerne

Intra-Row Weed Control by use of Band Steaming

Disinfection of the soil by means of steaming has been a common method for eliminating weeds and fungal diseases. However, surface steaming of soil is a very energy-intensive process, and consequently, efforts have been made to develop a machine for narrow-band steaming of the soil under and around rows of cultivated plants prior to seeding. The use of this machine may achieve up to 90% energy savings, and will also reduce the amount of damage to the flora and fauna. Tests have shown that soil temperatures exceeding 70C will be needed to protect against germination of weed seeds. For band heating such a treatment in 50 cm rows requires about 5.8 GJ/ha

Tromletørring skal sikre kvalitetskorn

Svampevækst i korn kan forringe kvaliteten og i værste fald gøre det sundhedsskadeligt for både dyr og mennesker. Nye forsøg viser, at tromletørring kan reducere svampeforekomsten markant uden i øvrigt at forringe kvalitete

Rækkedampning, effekter og økonomi

Der er udviklet en maskine til dampbehandling af jorden inden såning med henblik på at ødelægge ukrudtsfrøs spireevne. Princippet i maskinen er, at processen sker i et lukket kammer, som trækkes hen over det bånd der ønskes behandlet. Dampen ledes ind i kammeret og penetrerer effektivt ind i jordpartiklerne. Resultater har vist, at der kan opnås en effektiv ukrudtskontrol ved en behandlingstemperatur på 80-90 grader. Energiforbruget har ligget på ca. 400 l olie per ha. Økonomiske overslagsberegninger viser at der for et 4-rækket system vil være økonomisk balance i økologisk dyrkede gulerødder og løg ved arealstørrelser på ca. 8 ha

Tørring og rensning af korn

Tromletørring kan med fordel anvendes til kvalitetskorn som brødkorn og maltbyg. Den høje behandlingstemperatur reducerer vækst af skadelige svampe på kernerne

New optimized technique for mechanical control of Elymus repens

Elymus repens (coach grass) is traditionally controlled by repeated and prolonged stubble cultivation. However, the efficacy is strongly depending on weather and secondly on the exposure of rhizomes. The shorter the required period of cultivation stays the more compliance with the objective in organic farming where farmers aim at minimizing leaching of nutrients by keeping the soil plant-covered during autumn and winter. Effective technique and strategies for uprooting, exposing and destroying Elymus repens are needed. In a Danish organic research project the focus is on technological solutions for uprooting, exposing and destroying of the rhizomes within a short time span. Machines of standard type, modified machines and machines constructed for other purposes have been studied. The results show that it is difficult to achieve a high percentage of uprooting when using machines giving a high area capacity, e.g. spring loaded tine cultivator and rigid tine cultivator with modified spike discs at the rear

Establishing macroecological trait datasets: digitalization, extrapolation, and validation of diet preferences in terrestrial mammals worldwide

Ecological trait data are essential for understanding the broad-scale distribution of biodiversity and its response to global change. For animals, diet represents a fundamental aspect of species’ evolutionary adaptations, ecological and functional roles, and trophic interactions. However, the importance of diet for macroevolutionary and macroecological dynamics remains little explored, partly because of the lack of comprehensive trait datasets. We compiled and evaluated a comprehensive global dataset of diet preferences of mammals (“MammalDIET”). Diet information was digitized from two global and cladewide data sources and errors of data entry by multiple data recorders were assessed. We then developed a hierarchical extrapolation procedure to fill-in diet information for species with missing information. Missing data were extrapolated with information from other taxonomic levels (genus, other species within the same genus, or family) and this extrapolation was subsequently validated both internally (with a jack-knife approach applied to the compiled species-level diet data) and externally (using independent species-level diet information from a comprehensive continentwide data source). Finally, we grouped mammal species into trophic levels and dietary guilds, and their species richness as well as their proportion of total richness were mapped at a global scale for those diet categories with good validation results. The success rate of correctly digitizing data was 94%, indicating that the consistency in data entry among multiple recorders was high. Data sources provided species-level diet information for a total of 2033 species (38% of all 5364 terrestrial mammal species, based on the IUCN taxonomy). For the remaining 3331 species, diet information was mostly extrapolated from genus-level diet information (48% of all terrestrial mammal species), and only rarely from other species within the same genus (6%) or from family level (8%). Internal and external validation showed that: (1) extrapolations were most reliable for primary food items; (2) several diet categories (“Animal”, “Mammal”, “Invertebrate”, “Plant”, “Seed”, “Fruit”, and “Leaf”) had high proportions of correctly predicted diet ranks; and (3) the potential of correctly extrapolating specific diet categories varied both within and among clades. Global maps of species richness and proportion showed congruence among trophic levels, but also substantial discrepancies between dietary guilds. MammalDIET provides a comprehensive, unique and freely available dataset on diet preferences for all terrestrial mammals worldwide. It enables broad-scale analyses for specific trophic levels and dietary guilds, and a first assessment of trait conservatism in mammalian diet preferences at a global scale. The digitalization, extrapolation and validation procedures could be transferable to other trait data and taxa

Tromletørring god til øko-korn

Ny tørringsteknik kan fjerne svampe fra økologisk korn

Overvågning af kornlagre med integrerede trådløse sensorer

Temperatur og fugtighed i korn og frø skal kendes for at sikre optimalstyring af et tørringsanlæg og for at kontrollere, at lagringen sker udenkvalitetsforringelse. Resultaterne har vist, at trådløse sensorbolde kananvendes til sikker måling af temperatur og fugtighed via måling af denrelative luftfugtighed.På grundlag af det kendte ligevægtsforhold mellem vandindhold i kornog frø og den omgivende lufts relative fugtighed og temperatur omregnesmåleresultatet for de traditionelle kornarter og en række frøarter tilafgrødens vandprocent. Måleresultaterne vedrørende vandprocent kankun anvendes, når der ikke blæses i afgrøden. For at opnå brugbareresultater kræves minimum 3 timers stilstand.En temperaturstigning i et parti korn eller frø skyldes ofte nedbrydning afvaren og vækst af skadelige svampe. Hvis temperaturen eller fugtighedenstiger, registreres det via sensorboldene. Måleresultaterne kan direkteanvendes til at styre den nødvendige tørring og køling af afgrøden.Registreringerne vil ligeledes kunne anvendes til at dokumenterelagringsbetingelserne, eksempelvis ved krav om sporbarhed.Der er i forsøgene anvendt et totrins datatransmission set-up, hvor enrække sensorer enten direkte eller gennem en nabosensor sender datatil en basestation, hvorfra data trådløst videresendes til en internetserver,således at resultaterne kan ses på brugerens computer. Systemet harfungeret uden problemer. Trådløse sensorbolde kan således være etgodt alternativ til traditionelle systemer med faste målesensorer placereti lageret og forbundet med kabler til en kontrolboks