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1. Understanding the impacts of groundwater abstraction through long-term trends in water quality

Author:
Rasmussen, J.,   et al.   ; Gejl, R.N.; Rygaard, M.; Henriksen, H.J.; Bjerg, P.L.;     Show all 5 Authors
Source:
Water research 2019 v.156 pp. 241-251
ISSN:
0043-1354
Subject:
aquifers; calcium; drawdown; groundwater; groundwater extraction; monitoring; sulfates; time series analysis; water management; water quality
Abstract:
... It is vital to understand long-term trends in water quality parameters when assessing the sustainability of groundwater abstraction. Withdrawal-to-availability analysis is still used widely in groundwater management considering quantities and utilization rates based on in- and outflows. In this study, we took a step further than the water balance approach and carried out a detailed investigation o ...
DOI:
10.1016/j.watres.2019.02.026

2. Pre-harvest weed mapping of Cirsium arvense in wheat and barley with off-the-shelf UAVs

Author:
Rasmussen, J.,   et al.   ; Nielsen, J.; Streibig, J. C.; Jensen, J. E.; Pedersen, K. S.; Olsen, S. I.;     Show all 6 Authors
Source:
Precision agriculture 2019 v.20 no.5 pp. 983-999
ISSN:
1385-2256
Subject:
Cirsium arvense; algorithms; barley; batteries; cameras; cartography; color; detection; glyphosate; image analysis; spraying; stubble; unmanned aerial vehicles; vegetation; weeds; wheat
Abstract:
... The paper describes a procedure to detect green weeds in pre-harvest cereals using images from off-the-shelf UAVs with RGB cameras. All images used to develop and test the detection procedure were from fields infested with Cirsium arvense and in consequence, the procedure is called Thistle Tool. Thistle tool, however, may also detect other green weeds and may also be useful in post-harvest stubble ...
DOI:
10.1007/s11119-018-09625-7

3. Integrating groundwater stress in life-cycle assessments – An evaluation of water abstraction

Author:
Rasmussen, J.,   et al.   ; Gejl, R.N.; Bjerg, P.L.; Henriksen, H.J.; Hauschild, M.Z.; Rygaard, M.;     Show all 6 Authors
Source:
Journal of environmental management 2018 v.222 pp. 112-121
ISSN:
0301-4797
Subject:
decision making; drinking water; freshwater; global warming potential; groundwater; groundwater extraction; life cycle assessment; methodology; wastewater treatment; watersheds
Abstract:
... Understanding groundwater abstraction effects is vital for holistic impact assessments in areas depending on groundwater resources. The objective of our study was to modify the state-of-the-art AWaRe (available water remaining), freshwater impact assessment specifically for use in LCAs in areas dependent on groundwater resources. The new method, called “AGWaRe” (available groundwater remaining), r ...
DOI:
10.1016/j.jenvman.2018.05.058

4. Short‐term residual N unaffected by forbs in grass‐clover mixtures

Author:
Rasmussen, J.,   et al.   ; Dhamala, N. R.; Cong, W.‐F.; Carlsson, G.; Søegaard, K.; Eriksen, J.;     Show all 6 Authors
Source:
Soil use and management 2017 v.33 no.3 pp. 457-459
ISSN:
0266-0032
Subject:
caraway; chicory; dry matter accumulation; fertilizers; forbs; grasslands; nitrogen; nitrogen content; soil; spring barley
Abstract:
... We determined the effect on residual nitrogen (N) of including forbs (chicory, ribwort plantain and caraway) in perennial ryegrass‐red clover mixtures. Although soil N inputs during the grassland phase differed markedly between mixtures, in a pot experiment we found no differences in the potentially mineralizable N of the soil or in the dry matter production and N content of the spring barley test ...
DOI:
10.1111/sum.12368

5. Nitrate leaching and residual effect in dairy crop rotations with grass–clover leys as influenced by sward age, grazing, cutting and fertilizer regimes

Author:
Rasmussen, J.,   et al.   ; Eriksen, J.; Askegaard, M.; Søegaard, K.;     Show all 4 Authors
Source:
Agriculture, ecosystems & environment 2015 v.212 pp. 75-84
ISSN:
0167-8809
Subject:
Lolium multiflorum; Lupinus; autumn; barley; best management practices; corn; crop rotation; crops; cutting; dairy farming; fertilizers; grasslands; grazing; leaching; mixed cropping; nitrates; nutrient use efficiency; residual effects; sward
Abstract:
... Intensive dairy farming, with grass-arable crop rotations is challenged by low N use efficiency that may have adverse environmental consequences. We investigated nitrate leaching and N fertility effects of grass–clover leys for five years in two organic crop rotations with different grassland proportions (33 and 67%) and five grassland managements in terms of cutting, grazing, fertilization and co ...
DOI:
10.1016/j.agee.2015.07.001

6. Effect of four plant species on soil ¹⁵N-access and herbage yield in temporary agricultural grasslands

Author:
Rasmussen, J.; Rasmussen, J.,   et al.   ; Pirhofer-Walzl, K.; Eriksen, J.; Høgh-Jensen, H.; Søegaard, K.;     Show all 6 Authors
Source:
Plant and soil 2013 v.371 no.1-2 pp. 313-325
ISSN:
0032-079X
Subject:
Cichorium intybus; Lolium perenne; Medicago sativa; Trifolium repens; alfalfa; chicory; environmental impact; field experimentation; forage; grasslands; pure stands; soil depth
Abstract:
... We carried out field experiments to investigate if an agricultural grassland mixture comprising shallow- (perennial ryegrass: Lolium perenne L.; white clover: Trifolium repens L.) and deep- (chicory: Cichorium intybus L.; Lucerne: Medicago sativa L.) rooting grassland species has greater herbage yields than a shallow-rooting two-species mixture and pure stands, if deep-rooting grassland species ar ...
DOI:
10.1007/s11104-013-1694-0

7. Interactions between pre‐ and post‐emergence weed harrowing in spring cereals

Author:
RASMUSSEN, J,   et al.   ; BRANDSÆTER, L O; MANGERUD, K;     Show all 3 Authors
Source:
Weed research 2012 v.52 no.4 pp. 338-347
ISSN:
0043-1737
Subject:
biomass; correlation; crop yield; crops; developmental stages; grains; harrowing; harrows; soil; species diversity; spring; weed control; weeds
Abstract:
... Brandsæter LO, Mangerud K & Rasmussen J (2012) Interactions between pre‐ and post‐emergence weed harrowing in spring cereals. Weed Research52, 338–347. SUMMARY: Pre‐ and post‐emergence weed harrowing were studied in spring cereals in different environments and with two types of harrows in Norway during 2004–2006. The objectives were to investigate interactions between pre‐ and post‐emergence weed ...
DOI:
10.1111/j.1365-3180.2012.00925.x

8. Punch planting, flame weeding and stale seedbed for weed control in row crops

Author:
Rasmussen, J.
Source:
Weed research 2003 v.43 no.6 pp. 393-403
ISSN:
0043-1737
Subject:
planting date; weed control; forage crops; site preparation; no-tillage; plant density; crop yield; prescribed burning; planting seed; organic production; Beta vulgaris; Denmark
DOI:
10.1046/j.0043-1737.2003.00357.x

9. Forage herbs improve mineral composition of grassland herbage

Author:
Rasmussen, J.; Rasmussen, J.,   et al.   ; Pirhofer-Walzl, K.; Søegaard, K.; Høgh-Jensen, H.; Eriksen, J.; Sanderson, M.A.;     Show all 7 Authors
Source:
Grass and forage science 2011 v.66 no.3 pp. 415-423
ISSN:
0142-5242
Subject:
Carum carvi; Cichorium intybus; Plantago lanceolata; Sanguisorba minor; animal nutrition; caraway; chicory; forage grasses; grasslands; herbs; legumes; mineral content; ruminants; seed mixtures
Abstract:
... Provision of an adequate mineral supply in the diets of ruminants fed mainly on grassland herbage can present a challenge if mineral concentrations are suboptimal for animal nutrition. Forage herbs may be included in grassland seed mixtures to improve herbage mineral content, although there is limited information about mineral concentrations in forage herbs. To determine whether herbs have greater ...
DOI:
10.1111/j.1365-2494.2011.00799.x

10. Automated intelligent rotor tine cultivation and punch planting to improve the selectivity of mechanical intra‐row weed control

Author:
RASMUSSEN, J,   et al.   ; GRIEPENTROG, HW; NIELSEN, J; HENRIKSEN, CB;     Show all 4 Authors
Source:
Weed research 2012 v.52 no.4 pp. 327-337
ISSN:
0043-1737
Subject:
carrots; crops; cultivators; cutting; decline; disturbed soils; harrowing; mechanical weed control; plant density; plant establishment; planting; prediction; rotors; seeds; sowing; sugar beet; weeds
Abstract:
... Rasmussen J, Griepentrog HW, Nielsen J & Henriksen CB (2012). Automated intelligent rotor tine cultivation and punch planting to improve the selectivity of mechanical intra‐row weed control. Weed Research52, 327–337. SUMMARY: There is much research on technical aspects related to sensor and mapping techniques, which enable so‐called intelligent cultivators to target the intra‐row spaces within cro ...
DOI:
10.1111/j.1365-3180.2012.00922.x

11. Timing of post-emergence weed harrowing

Author:
RASMUSSEN, J.,   et al.   ; MATHIASEN, H.; BIBBY, B.M.;     Show all 3 Authors
Source:
Weed research 2010 v.50 no.5 pp. 436-446
ISSN:
0043-1737
Subject:
aggression; crop yield; developmental stages; harrowing; soil; spring barley; vegetation cover; weed control; weeds
Abstract:
... The timing of post-emergence weed harrowing was evaluated for two years in spring barley with crop-weed selectivity and crop recovery as the key parameters measured. Selectivity describes the relationship between weed control and crop soil cover immediately after harrowing, with crop soil cover as the percentage of the crop that has been covered by soil due to harrowing. Crop recovery describes th ...
DOI:
10.1111/j.1365-3180.2010.00799.x

12. Punch planting, flame weeding and delayed sowing to reduce intra‐row weeds in row crops

Author:
RASMUSSEN, J,   et al.   ; HENRIKSEN, C B; GRIEPENTROG, H W; NIELSEN, J;     Show all 4 Authors
Source:
Weed research 2011 v.51 no.5 pp. 489-498
ISSN:
0043-1737
Subject:
carrots; crops; disturbed soils; germination; manual weed control; mechanical weed control; onions; plant establishment; planting; sowing date; sugar beet; weeds
Abstract:
... Rasmussen J, Henriksen CB, Griepentrog HW & Nielsen J (2011). Punch planting, flame weeding and delayed sowing to reduce intra‐row weeds in row crops. Weed Research51, 489–498. SUMMARY: Punch planting has recently been suggested as a technique to reduce intra‐row weeds in organically grown row crops. The technique is to punch holes in the ground and seeds are then inserted, with a minimum of soil ...
DOI:
10.1111/j.1365-3180.2011.00858.x

13. Selenium Bioaccumulation in Stocked Fish as an Indicator of Fishery Potential in Pit Lakes on Reclaimed Coal Mines in Alberta, Canada

Author:
Rasmussen, J. B.,   et al.   ; Miller, L. L.; Palace, V. P.; Sterling, G.; Hontela, A.;     Show all 5 Authors
Source:
Environmental management 2013 v.52 no.1 pp. 72-84
ISSN:
0364-152X
Subject:
Oncorhynchus mykiss; Salvelinus fontinalis; bedrock; bioaccumulation; coal; compliance; fish; fisheries; habitats; hatcheries; human health; invertebrates; lakes; metals; mining; risk; selenium; water quality; wildlife; Alberta
Abstract:
... Pit lakes are a common reclamation strategy for open pit mines; however, there is a concern about their water quality and suitability as fish habitat because they are often contaminated by metals or metalloids. This study assessed the exposure of fish and invertebrates to selenium (Se) and other metals and metalloids in pit lakes formed by open pit coal mining in Tertiary (thermal coal) and in Cre ...
DOI:
10.1007/s00267-013-0038-4
PubMed:
23665755

14. Multicompartment Gravel Bed Flume to Evaluate Swim-Up Success of Salmonid Larvae

Author:
Rasmussen, J. B.,   et al.   ; Pilgrim, N. L.; Royer, R.; Ripley, L.; Underwood, J.; Hontela, A.;     Show all 6 Authors
Source:
North American journal of fisheries management 2013 v.33 no.1 pp. 71-78
ISSN:
1548-8675
Subject:
Oncorhynchus clarkii; Oncorhynchus mykiss; Salvelinus fontinalis; dissolved oxygen; drought; egg masses; eggs; environmental assessment; fish; fisheries; floods; gravel; hatcheries; hatching; larvae; pH; rearing; temperature; toxic substances; yolk sac
Abstract:
... Swim-up success, the proportion of fry emerging from a gravel redd, is difficult to quantify in the field, and currently available laboratory systems are limited. We used custom-built gravel bed flumes to assess the swim-up success of Rainbow Trout Oncorhynchus mykiss , Brook Trout Salvelinus fontinalis , and Cutthroat Trout Oncorhynchus clarkii . Flumes were built with compartments to separate in ...
DOI:
10.1080/02755947.2012.741556

15. Opening the "black box" of agro-scientific expert knowledge - and bringing the perspectives back into the agricultural university

Author:
Rasmussen, J.,   et al.   ; Kaltoft, P.;     Show all 2 Author
Source:
Journal of agricultural education and extension 2004 v.10 no.4 pp. 163-170
ISSN:
1389-224X
Subject:
agricultural education; extension education; higher education; organic production; experts; Denmark

16. Investigating the selectivity of weed harrowing with new methods

Author:
RASMUSSEN, J.,   et al.   ; BIBBY, B.M.; SCHOU, A.P.;     Show all 3 Authors
Source:
Weed research 2008 v.48 no.6 pp. 523-532
ISSN:
0043-1737
Subject:
developmental stages; field experimentation; harrowing; harrows; image analysis; row spacing; soil; spring barley; weed control; weeds; Ontario
Abstract:
... In six field experiments on post-emergence weed harrowing in spring barley, the effects of row spacing, timing, direction and orientation on crop/weed selectivity were investigated. The efficacies of increasing intensities of harrowing generated either by increasing number of passes or increasing driving speed were also tested. Selectivity was defined as the relationship between crop burial in soi ...
DOI:
10.1111/j.1365-3180.2008.00661.x

17. Cyanobacterial composition of microbial mats from an Australian thermal spring: a polyphasic evaluation

Author:
Rasmussen, J. Paul,   et al.   ; McGregor, Glenn B.;     Show all 2 Author
Source:
FEMS microbiology ecology 2008 v.63 no.1 pp. 23-35
ISSN:
0168-6496
Subject:
DNA; Geitlerinema; Leptolyngbya; Oscillatoria amphigranulata; biomass; gel electrophoresis; hot springs; microbial communities; phylogeny; phylotype; polymerase chain reaction; Australia; New Zealand
Abstract:
... Cyanobacterial composition of microbial mats from an alkaline thermal spring issuing at 43-71 °C from tropical north-eastern Australia are described using a polyphasic approach. Eight genera and 10 species from three cyanobacterial orders were identified based on morphological characters. These represented taxa previously known as thermophilic from other continents. Ultrastructural analysis of the ...
DOI:
10.1111/j.1574-6941.2007.00405.x
PubMed:
18081588

18. Alternative versus conventional attitudes in higher agricultural education

Author:
Rasmussen, J.,   et al.   ; Kaltoft, P.;     Show all 2 Author
Source:
Biological agriculture & horticulture 2003 v.20 no.4 pp. 347-363
ISSN:
0144-8765
Subject:
agricultural education; college students; professionals; universities; public opinion; sustainable agriculture; alternative farming; agriculture; Denmark
DOI:
10.1080/01448765.2003.9754978

19. Assessment of leaf cover and crop soil cover in weed harrowing research using digital images

Author:
RASMUSSEN, J.,   et al.   ; NØRREMARK, M.; BIBBY, BM;     Show all 3 Authors
Source:
Weed research 2007 v.47 no.4 pp. 299-310
ISSN:
0043-1737
Subject:
buried soils; cameras; color; developmental stages; digital images; grains; harrowing; image analysis; leaves; weeds
Abstract:
... Objective assessment of crop soil cover, defined as the percentage of leaf cover that has been buried in soil because of weed harrowing, is crucial to further progress in post-emergence weed harrowing research. Up to now, crop soil cover has been assessed by visual scores, which are biased and context-dependent. The aim of this study was to investigate whether digital image analysis is a feasible ...
DOI:
10.1111/j.1365-3180.2007.00565.x

20. Potato tuber yield and quality and soil inorganic nitrogen as affected by timing of ridging with and without catch crops

Author:
Rasmussen, J.,   et al.   ; Henriksen, C.B.; Mølgaard, J.P.;     Show all 3 Authors
Source:
Soil & tillage research 2007 v.94 no.1 pp. 36-46
ISSN:
0167-1987
Subject:
agricultural soils; sand; sandy loam soils; ridging; seasonal variation; crop yield; crop quality; potatoes; tubers; Solanum tuberosum; catch crops; nitrogen; plowing; Denmark
DOI:
10.1016/j.still.2006.06.009