Conventional and organic cropping systems at Suitia VI: Insect populations in barley

In 1988, insects were sampled from tillers and by pitfall trapping in a long-term field experiment consisting of plots of organic and conventional barley. The organic crops suffered from lack of nitrogen and from draught stress, and growth and development were retarded. The stand characteristics were suggested to be the major determinants of the fourfold higher densities of Rhopalosiphum padi(L.) (Horn., Aphididae) and the 50 % lower densities of Frankliniella tenuicornis Uzel (Thys., Thripidae) in the conventional than in the organic barley. The 75 % lower catch rate of Bembidion spp. (Col., Carabidae) in the conventional barley was attributed to lower activity resulting from the more closed canopy and more dense crop. However, the effect of an aphicide applied to the conventional crop was confounded with the true habitat effects. The densities of Coccinella seplempunclata L. (Col., Coccinellidae) were almost three times higher in the conventional than in the organic barley, which in turn was attributed to the higher prey (aphid) densities.

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Spectroscopic behaviour of 14C-labeled humic acids in a long-term field experiment with three cropping systems

Soil Research ◽

10.1071/sr08231 ◽

2009 ◽

Vol 47 (5) ◽

pp. 459 ◽

Cited By ~ 18

Author(s):

Michael Tatzber ◽

Michael Stemmer ◽

Heide Spiegel ◽

Christian Katzlberger ◽

Franz Zehetner ◽

...

Keyword(s):

Field Experiment ◽

Crop Rotation ◽

Humic Acids ◽

Cropping Systems ◽

Farmyard Manure ◽

Alkyl Groups ◽

Ft Ir ◽

Bare Fallow ◽

Term Field

The stabilisation of 14C-labelled farmyard manure was investigated under different cropping systems (crop rotation, monoculture, and bare fallow) in a long-term field experiment established in 1967. Solid-state 13C-NMR of bulk soils yielded a gradient of increasing aromatic properties in the order: straw manure–crop rotation < straw manure–monoculture < straw and farmyard manure–bare fallow. The opposite trend was observed for O-alkyl groups. The farmyard manure–bare fallow treatment was used to investigate changes of humic acids (HAs) with time. The FT-IR bands of aromatics, carbonyl groups, and a band of methyls and benzene rings increased over the 36 years of the experiment, whereas 2 amide bands and a band of sulfone and/or ester groups decreased. Fluorescence spectroscopy verified the increase in aromatic properties with age. Consequently, during soil organic matter stabilisation, HAs showed increasing properties of carbonyl and aromatic groups, whereas amidic groups decreased. The dynamic character of HAs, as shown by 14C, was also reflected by distinct spectroscopic changes over the period of investigation.

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KMnO4 determination of active carbon for laboratory routines: three long-term field experiments in Austria

Soil Research ◽

10.1071/sr14200 ◽

2015 ◽

Vol 53 (2) ◽

pp. 190 ◽

Cited By ~ 9

Author(s):

M. Tatzber ◽

N. Schlatter ◽

A. Baumgarten ◽

G. Dersch ◽

R. Körner ◽

...

Keyword(s):

Field Experiment ◽

Field Experiments ◽

Cropping Systems ◽

Organic Amendments ◽

Sodium Oxalate ◽

Tillage Systems ◽

Organic C ◽

Significant Difference ◽

Term Field

Recent studies show that a labile soil carbon (C) fraction determined with potassium permanganate (KMnO4) reflects the type of soil management. The present study combines the method for determining the active C (AC) pool with an alternative titration of the 0.02 m KMnO4 solution with sodium oxalate (Na2C2O4) for routine laboratory analyses. Three long-term field experiments investigated: (i) different cropping systems and 14C-labelled organic amendments, (ii) three different tillage systems, and (iii) the application of four different kinds of compost. The results showed the depletion of AC in the permanent bare-fallow system of the 14C-labelled field experiment. When calculating the ratio AC/total organic C (TOC), the depletion of the AC/TOC curve reflected a priming effect, in accord with previous work. We obtained significant positive correlations of AC with TOC, total nitrogen (Nt), humic acid-C and remaining 14C-labelled material. The AC in the tillage systems experiment was significantly (P < 0.05) different between all three tillage treatments at 0–10 cm depth, and the ratio AC/TOC also revealed a significant difference between minimum and conventional tillage treatments at 10–20 cm. For the compost field experiment, significant differences occurred between plots fertilised solely with N and plots receiving organic amendments. The AC/TOC ratio of the sewage sludge amendment was significantly lower than in all other systems. Correlations of AC with TOC for all samples of the different long-term field experiments revealed different behaviours in different soil types. The correlations of AC with Nt showed higher coefficients than with TOC. The applied methodology has a potential for sensitive and reliable detections of differences in soil organic matter characteristics.

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Crop straw recycling prevents anthropogenic desilication of agricultural soil–plant systems in the temperate zone – Results from a long-term field experiment in NE Germany

Geoderma ◽

10.1016/j.geoderma.2021.115187 ◽

2021 ◽

Vol 403 ◽

pp. 115187

Author(s):

Daniel Puppe ◽

Danuta Kaczorek ◽

Jörg Schaller ◽

Dietmar Barkusky ◽

Michael Sommer

Keyword(s):

Field Experiment ◽

Agricultural Soil ◽

Temperate Zone ◽

Crop Straw ◽

Ne Germany ◽

Term Field

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On the way towards conservation tillage-soil moisture and mineral nitrogen in a long-term field experiment in Germany

Soil and Tillage Research ◽

10.1016/j.still.2011.07.001 ◽

2011 ◽

Vol 115-116 ◽

pp. 80-87 ◽

Cited By ~ 17

Author(s):

Sabine Gruber ◽

Jens Möhring ◽

Wilhelm Claupein

Keyword(s):

Soil Moisture ◽

Field Experiment ◽

Conservation Tillage ◽

Mineral Nitrogen ◽

Term Field ◽

The Way

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Exploring the Vis-NIR wavelength importance in SOC models under field and lab conditions in a long-term field experiment

10.5194/egusphere-egu21-12713 ◽

2021 ◽

Author(s):

Javier Reyes ◽

Mareike Ließ

Keyword(s):

Field Experiment ◽

Spectral Response ◽

Nir Spectroscopy ◽

Partial Least Square ◽

Least Square ◽

Field Conditions ◽

Partial Least Square Regression ◽

Preprocessing Technique ◽

Term Field

<p>Soil organic carbon (SOC) is of particular interest in the study of agricultural systems as an indicator of soil quality and soil fertility. In the use of Vis-NIR spectroscopy for SOC detection, the interpretation of the spectral response with regards to the importance of individual wavelengths is challenging due to the soil&#8217;s composition of multiple organic and minerals compounds. Under field conditions, additional aspects affect the spectral data compared to lab conditions. This study compared the spectral wavelength importance in partial least square regression (PLSR) models for SOC between field and lab conditions. Surface soil samples were obtained from a long-term field experiment (LTE) with high SOC variability located in the state of Saxony-Anhalt, Germany. Data sets of Vis-NIR spectra were acquired in the lab and field using two spectrometers, respectively. Four different preprocessing methods were applied before building the models. Wavelength importance was observed using variable importance in projection. Differences in wavelength importance were observed depending on the measurement device, measurement condition, and preprocessing technique, although pattern matches were identifiable, especially in the NIR range. It is these pattern matches that aid model interpretation to effectively determine SOC under field conditions.</p>

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Dynanics of plant-available phosphorus in the long-term field experiment with fertilizers on calcareous chernozem of Moldova

Vìsnik Lʹvìvsʹkogo nacìonalʹnogo agrarnogo unìversitetu Agronomìâ ◽

10.31734/agronomy2019.01.222 ◽

2019 ◽

pp. 222-224

Author(s):

D. M. Indoitu ◽

◽

D. D. Indoitu ◽

Keyword(s):

Field Experiment ◽

Available Phosphorus ◽

Term Field

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A LONG-TERM FIELD EXPERIMENT WITH COMMERCIAL FERTILIZERS AND MANURE: I. Fertility levels and crop yields in a rotation of swedes, oats and hay

Canadian Journal of Soil Science ◽

10.4141/cjss60-019 ◽

1960 ◽

Vol 40 (2) ◽

pp. 136-145 ◽

Cited By ~ 2

Author(s):

L. B. MacLeod ◽

R. F. Bishop ◽

L. P. Jackson ◽

C. R. MacEachern ◽

E. T. Goring

Keyword(s):

Field Experiment ◽

Cation Exchange Capacity ◽

Crop Yields ◽

Residual Effect ◽

Exchange Capacity ◽

Exchangeable Potassium ◽

Soluble Phosphorus ◽

Initial Content ◽

Term Field

In a field experiment, conducted from 1936 to 1957, a rotation of swedes, oats and hay was followed and treatments included commercial fertilizers and manure.Changes in the chemical composition of the soil during the experiment included significant decreases in soil organic matter, total nitrogen and cation exchange capacity. In no case was the initial content of exchangeable potassium maintained and although changes in adsorbed and easily acid-soluble phosphorus were negligible with a number of treatments only one resulted in a significant increase.The treatments were applied in the swede year and yield differences with this crop were greater than for either the oats or hay. Data for the latter two crops indicated that with most of the treatments there was a tendency for yields to decline as the experiment progressed. This was not the case with swedes where variation in yields with rotation cycles was greater than it was in the case of oats or hay. There was a considerable residual effect from manure, and phosphorus had a greater effect on yields than either nitrogen or potassium.

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