SABIIA - Sistema Aberto e Integrado de Informação em Agricultura (Sabiia)

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

Subsoil loosening eliminated plough pan but had variable effect on crop yield

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

Effekt af tekstur og struktur på roddybden

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...

Non-inversion tillage effects on soil mechanical properties of a humid sandy loam

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; 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

Mekanisk jordløsning fjernede pløjesål men gav varierende effekt på udbyttet

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

Jordløsning

Jordløsning

Subsoil loosening in a crop rotation for organic farming eliminated plough pan with mixed effects on crop yield

Palavras-chave: Crop health; Quality; Protection Soil tillage.

Ano: 2004

URL: http://orgprints.org/7821/1/7821.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

Jordbearbejdning i økologisk jordbrug – pløjedybde og ikke-vendende jordløsning [Soil tillage in organic farming – ploughing depth and non-inversion deep tillage]

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

Soil quality aspects of humid sandy loams as influenced by organic and conventional long-term management

Soil mechanical behaviour of sandy loams in a temperate climate: case studies on long-term effects of fertilization and crop rotation.

Schjønning, Per; Elmholt, Susanne; Munkholm, Lars J.; Debosz, Kasia.

The development of low-input farming systems requires knowledge of the extent to which management characteristics influence the soil as a habitat for micro-organisms and a medium for plant growth. This paper presents a study of long-term effects of organically and conventionally cultivated systems on a range of soil physical, chemical and biological characteristics in Denmark. Seven soils were included, falling into three groups (I¯III). Each group consists of an organically managed soil (Org) referenced by one or two conventionally managed soils (Conv) with the same soil type (sandy loam) and pedological history. All organically managed soils were dairy farm soils (H), which had been organically managed for 46, 47 and 40 years, respectively. They had...

Tipo: Journal paper

Palavras-chave: Composting and manuring; Soil quality; Crop combinations and interactions; Soil tillage; Farming Systems; Soil biology.

Ano: 2002

URL: http://orgprints.org/40/1/manus1.pdf

Munkholm, Lars J.; Schjønning, Per; Petersen, Carsten T..

Two case studies on Danish sandy loams investigated long-term effects of fertilization and crop rotation. Case Study 1 compared a diversely cropped organically farmed soil (DFG(1)) with a conventionally farmed soil predominantly growing annual crops (DFA), both receiving animal manure. In Case Study 2, a diversely cropped organically managed soil DFG(2)) receiving animal manure was compared with an almost exclusively cereal cropped conventionally farmed soil receiving no animal manure (CCC). A multi-level experimental strategy was followed to compare integrating field methods with specialized laboratory methods. Ease of tillage was described in the field and characterized using a drop shatter field test and by measuring aggregate tensile strength. Fitness...

Tipo: Journal paper

Palavras-chave: Composting and manuring; Soil quality; Production systems; Crop combinations and interactions; Soil tillage; Farming Systems.

Ano: 2001

URL: http://orgprints.org/61/1/Soil_mechanical.pdf

Effect of Water Regime on Aggregate-tensile Strength, Rupture Energy, and Friability

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

Subsoil loosening eliminated plough pan but had variable effect on crop yield

Munkholm, Lars J.; Olesen, Jørgen E.; Schjønning, Per.

The effect of subsoil loosening to c. 35 cm depth was studied in an organic crop rotation experiment at Flakkebjerg (sandy loam) and Foulum (loamy sand). In each of the years 2000-2003 half of 4 plots per site was loosened in the autumn in a young grass-clover. Penetration resistance was recorded yearly. Detailed soil physical properties were determined for the Foulum site in 2003. Aboveground winter wheat growth was followed during the 2002/03 growing season using spectral reflectance measurements. Root growth was followed during the 2002/03 growing season at Foulum using the minirhizotron technique. Crop yield was determined every year in all treated plots. The Paraplow treatment effectively loosened the plough pan. Loosening in the grass-clover crop...

Palavras-chave: Crop health; Quality; Protection Crop combinations and interactions Soil quality Soil tillage.

Ano: 2005

URL: http://orgprints.org/7824/1/7824.doc

The spade analysis

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.

Soil Fragmentation and Friability. Effects of Soil Water and Soil Management

Palavras-chave: Soil; Soil biology; Soil quality; Soil tillage.

Ano: 2005

URL: http://orgprints.org/7822/1/7822.doc

Multi-level assessment of soil quality – linking reductionistic and holistic methodologies

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

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...

Soil structure dynamics: Effects of management and water content

Palavras-chave: Soil quality; Research methodology and philosophy.

Ano: 2000

URL: http://orgprints.org/51/1/manus4.pdf

Munkholm, Lars J.; Schjønning, Per; Elmholt, Susanne.

A review is given of the last 5 years research on soil structure dynamics carried out at the Danish Institute of Agricultural Sciences. The studies were initiated as part of a large programme focussing on the development of organic farming in Denmark. In organic farming a healthy and living soil is highly valued. Holistic thinking is also a key element in the organic farming concept. In order to integrate a holistic thinking in our soil structure research a multidisciplinary approach was adapted that integrated soil physics, chemistry and microbiology. In addition, soil structure was studied at different levels from undisturbed “whole soil” in the field to specialized reductionistic studies using size separated or remoulded soil in the laboratory. In a...

Sådan sikres en bekvem jord

Palavras-chave: Soil quality; Production systems; Research methodology and philosophy; Soil tillage; Soil biology.

Ano: 2002

URL: http://orgprints.org/52/1/canada.pdf

Biotic and abiotic binding and bonding mechanisms in soils with long-term differences in management

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

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...

Jordløsning i sædskifteforsøg

Palavras-chave: Soil quality; Production systems; Soil biology.

Ano: 2000

URL: http://orgprints.org/49/1/manus3ny.pdf