|
|
|
Registros recuperados: 19 | |
|
|
Munkholm, Lars J.; Andersen, Mathias N.. |
Dybdegående rodvækst giver en række fordele både i relation til planteproduktion og miljø. Der kan opnås en bedre udnyttelse af næringsstoffer og vand, et øget potentiale for biologisk omsætning i dybere jordlag og der ophobes kulstof i dybere jordlag. Rodudviklingen er i høj grad betinget af naturgrundlaget ( klima, jordtype og jordbundsudvikling), men afhænger også stærkt af dyrkningen (jordbearbejdning, trafik, gødskning, vanding, dræning,, kalkning mv.). Jordfysiske faktorer er ofte af dominerende betydning for rodudviklingen i dyrkede jorde. Mekanisk modstand har meget stor betydning for rodvæksthastighed og –nedtrængning, men er samtidig en meget sammensat størrelse, som påvirkes af bl.a. tekstur, struktur, volumenvægt og vandindhold, der igen... |
Tipo: Conference paper, poster, etc. |
Palavras-chave: Crop health; Quality; Protection Crop combinations and interactions Soil. |
Ano: 2006 |
URL: http://orgprints.org/7825/1/7825.doc |
| |
|
| |
|
| |
|
|
Munkholm, Lars J.; Schjønning, Per; Debosz, Kasia; Jensen, Henry E.; Christensen, Bent T.. |
Current concern for soil quality has stimulated research on soil biological and chemical properties. In contrast, the mechanical behaviour of soil is somewhat neglected. We have examined the effects on soil mechanical properties of more than 100years of contrasting fertilization employing three treatments from the Askov long-term experiment: UNF (unfertilized), NPK (mineral fertilized) and AM (animal manured). We have measured tensile strength of aggregates when air-dry and when adjusted to 10, 30 and 100kPa pressure potential. Four aggregate size classes were investigated (1-2, 2-4, 4-8 and 8-16mm diameter). Soil fragmentation was characterized in the field using a drop-shatter test. Bulk soil strength was determined in the field using a shear vane and a... |
Tipo: Journal paper |
Palavras-chave: Soil. |
Ano: 2002 |
URL: http://orgprints.org/32/1/j.1365-2389.2002.00424.x.pdf |
| |
|
|
Munkholm, Lars J.; Olesen, Jørgen E.. |
Pakning af underjorden forekommer på en stor del af den dyrkede jord. Særligt er en rodhæmmende pløjesål et udbredt problem. Pakning af underjorden forringer kvantitet og kvalitet af afgrøderne, kan give problemer med færdsel på jorden under våde forhold og har negativ effekt på miljøet fx i form af øget risiko for N udvaskning. Danmarks JordbrugsForskning har i et FØJO-projekt undersøgt effekten af at løsne den rodhæmmende pløjesål i de økologiske sædskifteforsøg på Flakkebjerg og Foulum. |
Tipo: Journal paper |
Palavras-chave: Nutrient turnover; Soil; Soil quality. |
Ano: 2004 |
URL: http://orgprints.org/7819/1/7819.PDF |
| |
|
|
Munkholm, Lars J.. |
Den teknologiske udvikling i landbruget igennem de seneste årtier har betydet, at der bruges mindre og mindre tid med at dyrke hver enkelt ha, og tiden tilbringes i et komfortabelt førerhus flere meter over jorden. Spørgsmålet er om vi er ved at miste fornemmelsen for jord. Hvad gør jorden mere bekvem? Ja mange vil sikkert svare at husdyrgødning, halmnedmuldning, kompost etc. gør jorden mere bekvem. Andre vil sikkert svare at strukturskader gør jorden ubekvem. I et forskningsprojekt ved Danmarks JordbrugsForskning er der blevet sat tal på effekten af langvarig tilførsel af husdyrgødning og af pakning og intensiv jordbearbejdning. |
Tipo: Newspaper or magazine article |
Palavras-chave: Soil quality; Soil tillage. |
Ano: 2002 |
URL: http://orgprints.org/7817/1/7817.pdf |
| |
|
|
Munkholm, Lars J.. |
This method describes the present status of the soil tilth and to relate it to past management practices. Key criteria include soil texture, structure (layering, units, density, colour), compaction, anaerobism, root growth, soil fauna and decomposition of organic matter. A record form describing each property is completed. |
Tipo: Conference paper, poster, etc. |
Palavras-chave: Soil; Soil biology; Soil quality; Soil tillage. |
Ano: 2005 |
URL: http://orgprints.org/7822/1/7822.doc |
| |
|
|
Munkholm, Lars J.. |
Soil fragmentation is a primary aim in most tillage operations in order to create a soil environment favourable for crop establishment and growth. Soils vary around the world from those exhibiting a self-mulching nature to those of a hardsetting nature. These extremes have been reported for Australian and other tropical and subtropical soils. In humid temperate climates, soil tillage is generally needed in order to produce a favourable environment for crop establishment and growth. The ease of preparing a favourable arable layer depends on complex interactions between climate, soil and the tillage implement. Especially soil water affects soil strength and fragmentation properties and thereby the ease of preparing a suitable arable layer. Soil management... |
Tipo: Thesis |
Palavras-chave: Soil quality; Production systems; Soil tillage; Specific methods; Soil biology. |
Ano: 2002 |
URL: http://orgprints.org/56/1/Lars_samle_syntese.pdf |
| |
|
| |
|
|
Munkholm, Lars J.; Schjønning, Per; Rasmussen, Karl J.. |
Optimisation of soil tilth is of paramount importance in organic plant production in order to enhance crop growth. Non-inversion and reduced tillage systems are often claimed to be preferable for organic farming. The purpose of this study was to evaluate the early stage effects of converting a mouldboard-ploughed soil to a non-inversion tillage system. A multi-level experimental strategy including in situ, on-site and laboratory methods was followed in order to relate quantitative measures of soil physical properties directly to soil behaviour in the field. A non-inversion deep soil loosening (0¯35 cm) tillage system (NINV) was compared to a conventional mouldboard ploughing and harrowing tillage system (CONV). The experimental site was located on an... |
Tipo: Journal paper |
Palavras-chave: Soil quality. |
Ano: 2001 |
URL: http://orgprints.org/39/1/manus.pdf |
| |
|
| |
|
|
Olesen, Jørgen E.; Munkholm, Lars J.. |
Compacted subsoil may reduce root growth with resulting effects on plant uptake of water and nutrients. In organic farming systems subsoil loosening may therefore be considered an option to increase nutrient use efficiencies. We investigated the effect of subsoil loosening with a Paraplow to c. 35 cm depth in an organic farming experiment at Foulum (loamy sand) and Flakkebjerg (sandy loam) in Denmark. In each of the years 2000 to 2004 one half of four plots per site were loosened in the autumn in a young grass-clover crop established by undersowing in spring barley. The grass-clover was grown for a year as a green manure crop and followed by winter wheat, lupin:barley and spring barley in the following three years. On-land ploughing was used for all these... |
Tipo: Journal paper |
Palavras-chave: Soil tillage. |
Ano: 2007 |
URL: http://orgprints.org/7804/1/7804.pdf |
| |
|
|
Schjønning, Per; Rasmussen, Karl J.; Munkholm, Lars J.; Nielsen, Peter S.. |
I perioden 1996 til 2000 gennemførtes et markforsøg med forskellige jordbearbejdnings-systemer på Den økologiske Forsøgsstation Rugballegaard. Forsøgsarealet blev omlagt til økologisk drift i forbindelse med projektets start i 1996. Undersøgelserne gennemførtes i et fem-marks skifte, der ligeledes blev kørt ind i forbindelse med projektet. Det drejer sig om et såkaldt blandet sædskifte med byg/ært m. udlæg, 1. års kløvergræs, 2. års kløvergræs, havre og vinterhvede. Forsøget blev anlagt i fem marker (B1-B5), hvilket indebærer, at alle skiftets afgrøder blev dyrket hvert år. Fire forskellige jordbearbejdningssystemer blev undersøgt i et randomiseret blokforsøg med 4 blokke. De fire behandlinger omfattede to systemer med pløjning, nemlig led A med 20 cm... |
Tipo: Report |
Palavras-chave: Soil quality; Weed management; Soil tillage; Soil biology. |
Ano: 2002 |
URL: http://orgprints.org/188/1/djfm82.pdf |
| |
|
|
Munkholm, Lars J.; Olesen, Jørgen E.. |
Subsoil compaction is a widespread problem on Danish arable soils and especially in form of plough pan compaction. Subsoil compaction may reduce crop yield and quality, increase negative environmental impact (e.g. in form of increased nitrogen leaching), and reduce soil workability and traffic ability of the soil. Danish Institute of Agricultural Sciences has in a DARCOF project investigated the effect of subsoil loosening. The investigations were carried out in an organic crop rotation experiment at two sandy loams: Flakkebjerg (13% clay) and Foulum (8% clay). |
Tipo: Journal paper |
Palavras-chave: Nutrient turnover; Soil. |
Ano: 2005 |
URL: http://orgprints.org/7820/1/7820.PDF |
| |
|
|
Munkholm, Lars J.. |
Skadelig pakning af underjorden forekommer på en stor del af de dyrkede jord. Særligt er en rodhæmmende pløjesål et udbredt problem. Pakning af underjorden indvirker negativt på både kvantitet og kvalitet af afgrøderne, kan give problemer med at færdes på jorden og har negativ effekt på miljøet. Danmarks JordbrugsForskning har undersøgt effekten af at løsne en rodhæmmende pløjesål i de økologiske sædskifteforsøg på Flakkebjerg og Foulum. Samlet viser resultaterne fra denne og tidligere undersøgelser, at mekanisk løsning sjældent giver et betydende merudbytte efter løsning. Manglende planteeffekt kan i nogle tilfælde forklares med hurtig genpakning af den løsnede jord. Men selv hvor genpakning er minimeret har vi ikke fundet markant merudbytte efter... |
Tipo: Newspaper or magazine article |
Palavras-chave: Soil; Soil quality; Soil tillage. |
Ano: 2005 |
URL: http://orgprints.org/7818/1/7818.pdf |
| |
|
|
Elmholt, Susanne; Munkholm, Lars J.; Debosz, Kasia; Schjønning, Per. |
During the last decades Denmark has experienced a growing interest in low-input farming systems like organic farming. These systems rely on a high soil fertility to maintain nutrient availability and plant health. Soil aggregation contributes to this fertility, because it is crucial to soil porosity, aeration and infiltration of water. This paper reports a study of two pairs of differently managed, neighboring fields. The aim was to elucidate long-term effects of the different farming systems on physical and biological variables with influence on bonding and binding mechanisms of soil aggregation. Each pair consists of an organically grown dairy farm soil, based on a forage crop rotation system, including grass (Org-FCS(G)) and a conventionally managed... |
Tipo: Conference paper, poster, etc. |
Palavras-chave: Soil quality; Production systems; Soil biology. |
Ano: 2000 |
URL: http://orgprints.org/49/1/manus3ny.pdf |
| |
|
|
Munkholm, Lars J.; Kay, Bev D.. |
The effect of water regime on aggregate-tensile strength, rupture energy, and friability index was studied in two experiments on sandy loam soils (Glossic Phaeozem/WRB 1998). In Exp. 1, soil from a long-term, 5-yr crop rotation receiving animal manure (dairy farm and grass, DFG) was compared with a soil (continuous cereal crop, CCC), which had grown almost continuous cereals and not received animal manure. In Exp. 2, soil from compacted plots (PAC) and uncompacted reference plots (REF) was sampled. The soil was air-dried and separated into four aggregate-size classes (i.e., 1–2, 2–4, 4–8, and 8–16 mm). Aggregate-tensile strength and rupture energy were measured on air-dry aggregates and on aggregates adjusted to -10, -30, -100, -350 kPa, and -166 MPa... |
Tipo: Journal paper |
Palavras-chave: Soil quality. |
Ano: 2002 |
URL: http://orgprints.org/31/1/SSSAJ_--_Munkholm_and_Kay_66_%283%29_702.htm |
| |
|
| |
|
|
Schjønning, Per; Munkholm, Lars J.; Debosz, Kasia; Elmholt, Susanne. |
Soil quality is often used as a qualitative, general term. However, quantification is an important feature of the scientific approach to nature. On the other hand, addressing specific soil parameters as indicators of soil quality includes a reduction of the whole soil system. Therefore, results obtained by specialized methodologies ought to be evaluated by methods integrating the soil characteristics in situ. In this presentation, results are given from an investigation of the tilth of two differently managed loamy soils. One of the soils had been managed for decades with a forage crop system (labeled FCS), which included fertilization with farmyard manure, while the other had been grown with a continuous cereal system (labeled CCS), receiving no input of... |
Tipo: Conference paper, poster, etc. |
Palavras-chave: Soil quality; Research methodology and philosophy. |
Ano: 2000 |
URL: http://orgprints.org/51/1/manus4.pdf |
| |
Registros recuperados: 19 | |
|
|
|