Sub-projects

Description of projects: 3. phase

A1 Productivity, N turnover and plant diversity of permanent pastures with differentiated swards.

  • PhD student: Dorothee Ebeling
  • Supervisor: Prof. Dr. J. Isselstein

A2 Nondestructive measurement of structural and functional stock parameter of heterogenous pastures.

  • PhD student: Hanieh Safari
  • Supervisor: Prof. Dr. M. Wachendorf

B1 Nutrient release from organic fertilizer into soil: Investigation and modeling

  • PhD student: Dennis Grunwald
  • Supervisor: Prof. Dr. B. Ludwig

B2 Impact of grazing intensity on the productivity, N dynamics and labile C and N pools of a soil under permanent pasture.

  • PhD student: Anja Nüsse
  • Supervisor: Prof. Dr. B. Ludwig

C1 Impact of soil management on C accumulation in subsoil.

  • PhD student: Juliane Strücker
  • Supervisor: Prof. Dr. R.G. Jörgensen

C2 Regulation of the interaction of soil temperature. moisture and microbial activity by management practices.

  • PhD student: Sibylle Faust
  • Supervisor: Prof. Dr. R.G. Jörgensen

D1 Composition of manure from cattle and their impact on nutrient availability and the emission potential of nitrogen, carbon and phosphorus compounds.

  • PhD student: Stephanie Meyer
  • Supervisor: Prof. Dr. A. Sundrum

D2 Variation of N excretion in faeces and urin as modulated by water uptake of goats in subtropical Oman.

  • PhD student: Mwanaima Ramadhan
  • Supervisor: Prof. Dr. E. Schlecht

E1 Nutrient and carbon dynamics in soils after application of a mixture of manure and biochar.

  • PhD student: Marco Gronwald
  • Supervisor: Prof. Dr. H. Flessa

E2 Impact of grassland ploughing on soil quality. Consequences for stable C and N pools and determination of turnover rates.

  • PhD student: Caroline Buchen
  • Supervisor: Prof. Dr. H. Flessa

F1 Impact of labeled goat faeces on C and N pools in a subtropical soil with different water regimes.

  • PhD student: Gunadhish Khanal
  • Supervisor: Prof. Dr. A. Bürkert


Description of projects - 2. phase

A1 Effect of plowing up grassland with different cultivation intensities on labile carbon and nitrogen pools in soil

  • Contact: Deborah Linsler
  • Project-leader: Prof. Dr. B. Ludwig

Aims of the project

Improve our understanding of the effects of grassland ploughing on labile C and N pools in soil

Methods

Density and aggregate fractionation, incubation experiments

A2 Effects of tillage intensity (conventional tillage, conservation tillage and no-till) on labile carbon and nitrogen pools in soil

  • Contact: Rouven Adruschkewitsch
  • Project-leader: Prof. Dr. B. Ludwig

Aims of the project

Study the effects of soil tillage on the decomposition of plant residues and short- and long-term storage of C and N in arable soils

Methods

Density and aggregate fractionation, incubation experiments

B1 Effect of tillage intensity and winter cover crop on nitrogen and phosphorus dynamics in soil

  • Contact: Christiane Piegholdt
  • Project-leader: Prof. Dr. B. Ludwig

Aims of the project

Improve our understanding of the effect of tillage, cover crops on C, N and P pools

Methods

Fractionation of P and B, aggregate fractionation and modeling

C1 Influence of the conversion of grassland with differing cultivation intensities on microbial soil properties

  • Contact: Murugan Rajasekaran
  • Project-leader: Prof. Dr. R.G. Jörgensen

Aims of the project

Study the microbial turnover and microbial  community structure as affected by tillage practises

Methods

Basal respiration, CFE, Ergosterol, Amino sugars

D2 Influence of polyphenoles and activated biochar on the digestibility of the diet and on the quality of goat manure under subtropical conditions

  • Contact: Amel Said Al-Kindi
  • Project-leader: Prof. Dr. E. Schlecht

Aims of the project

Analyse the influence of feeding tannin and activated biochar on digestibility and the microbial protein synthesis in rumen and colon and on N balances of the animal

Methods

Goat feeding trials, analyses of digestibility and digestion by Ytterbium labeled fiber material

E1 Effect of biogas slurry applications on carbon and nitrogen transformations in soil

  • Contact: Ulrike Wolf
  • Project-leader: apl. Prof. Dr. H. Flessa

Aims of the project

Analyse the effects of different digestates on emissions of climate change relevant gases. Investigate the influence of different digestates on C and N transformation in soil

Methods

Measurement of gas fluxes (NH3, N2O, CO2, CH4), soil N mineralisation, modeling, microcosm experiments, use of stable isotops

E2 Effect of plowing up grassland on carbon and nitrogen transformation processes in soils and their impact on climate

  • Contact: Greta Roth
  • Project-leader: apl. Prof. Dr. H. Flessa

Aims of the project

Analysis of the regulatory processes for C and N transformation in ploughed grassland soils

Methods

Field measurements of CO2, N2O, CH4, net mineralisation, CFE, Ergosterol

F1 Effect of polyphenols and biochar on the turnover of manure in irrigated subtropical agricultural systems

  • Contact: Mariko Nadine Ingold
  • Project-leader: Prof. Dr. A. Bürkert

Aims of the project

Test the efficiency of organic fertilizer application for vegetable croping systems in Oman, improvement of fertilizer practise to reduce C and N gaseous and leaching losses

Methods

Feeding trial, measurement of leaching and gaseous emission


Description of projects - 1. phase

A1 Effects of crop rotation and fertilization on labile C and N pools in sandy and silty soils under subtropical and temperate climates: experiments and modelling

  • Contact: Felix Heitkamp
  • Project-leader: Prof. Dr. B. Ludwig

Aims of the project

Improved understanding of the effects of the crop rotation and tillage on soil fertility

Methods

Density and aggregate fractionations, incubation experiments, litterbag experiments, modelling

A2 Effects of tillage on labile C and N pools: experiments and modelling

  • Contact: Anna Jacobs
  • Project-leader: Prof. Dr. B. Ludwig

Aims of the project

Improved understanding of the effects of the crop rotation and tillage on soil fertility

Methods

Density and aggregate fractionations, incubation experiments, litterbag experiments, modelling

B1 Dynamics of ions in sandy and silty soils under unsaturated conditions: experiments and modelling

  • Contact: Sandra Herrmann
  • Project-leader: Prof. Dr. B. Ludwig

Aims of the project

Analysis and modelling of the dynamics of Ca, K, Mg, NH4, NO3 and PO4 in agricultural soils with special considerations of texture, tillage and climatic conditions

Methods

Microcosm experiments, leachate sampling and analysis, use of stable isotopes,   sorption experiments, modelling using PHREEQC2 and PEST

B2 Gas fluxes and leachate losses in differently fertilized soils

  • Contact: Anja Sänger
  • Project-leader: Prof. Dr. B. Ludwig

Aims of the project

Analyse und Modellierung der Dynamiken von Ca2+, K+, Mg2+, NH4+, NO3- und PO43- in landwirtschaftlichen Böden unter besonderer Berücksichtigung der Textur, der Bearbeitung und des Klimas

Methods

Mikrokosmenexperimente, Gewinnung und Analyse von Lösungsproben, Einsatz stabiler Isotope, Erfassung von Gasflüssen (CO2, CH4, N2O), Modellierung (z.B. DNDC)

C1 Decomposition and microbial colonization of double-labelled litter in litter bags or mixed with soil in soils from temperate and tropical climates from organic farming systems

  • Contact: Nils Rottmann
  • Project-leader: Prof. Dr. R.G. Jörgensen

Aims of the project

Identifying the role of plant growth for litter decomposition

Methods

Use of stable isotopes, litterbag experiments, pot experiments, determination of microbial biomarkers

C2 Interactions between soil characteristics, above-ground biomass and soil microbial properties

  • Contact: Stefanie Heinze
  • Project-leader: Prof. Dr. R.G. Jörgensen

Aims of the project

Identifying the role of plant growth for litter decomposition

Methods

Use of stable isotopes, litterbag experiments, pot experiments, determination of microbial biomarkers

D1 Effects of the quality of manure from dairy cows on the availability of nutrients for microbial and plant growth

  • Contact:Daphne Jost
  • Project-leader: Prof. Dr. R.G. Jörgensen

Aims of the project

Understanding the interaction of feeding, microbial activity and soil fertility

Methods

Use of different forage composition, determination of N2O, extraction and analysis of microbial DNA, determination of adenylate energy charges

D2 Effects of different feeding regimes under subtropical conditions on the quality of manure from ruminants in relation to the availability of nutrients for microbial and plant growth

  • Contact: Husam Al-Asfoor
  • Project-leader: Prof. Dr. E. Schlecht

Aims of the project

Understanding the interaction of feeding, microbial activity and soil fertility

Methods

Use of different forage composition, use of marker substances, determination of adenylate energy charges

E1 Effect of fertilizer strategies (mineral fertilization, organic fertilization, N2 fixation) on N transformation and N2O emission in a crop rotation

  • Contact: Nadine Jäger
  • Project-leader: apl. Prof. Dr. Heiner Flessa

Aims of the project

Evaluation of the effects of different crops and tillage systems on the N2O emissions from different soils

Methods

Use of labelled substrates, field experiments, modelling

E2 Effect of humus accumulation in the topsoil on N dynamic with special consideration of N2O emissions

  • Contact: Konrad Siegfried
  • Project-leader: Prof. Dr. A. Bürkert

Aims of the project

Evaluation of the effects of different crops and tillage systems on the N2O emissions from different soils

Methods

Use of labelled substrates, field experiments, modelling

F1 Gaseous and leachate losses of C and N from fertilized and irrigated soils of a subtropical coastal oasis

  • Contact: Konrad Siegfried
  • Project-leader: Prof. Dr. A. Bürkert

Aims of the project

To assess the sustainability of different systems

Methods

Infrared spectroscopy, litterbag experiments, leachate sampling and analysis, use of stable isotopes, modelling

F2 Gaseous and leachate losses of C and N of subtropical and temperate agricultural land: effects of cropping system

  • Contact: Mohamed Al-Rawahi
  • Project-leader: Prof. Dr. A. Bürkert

Aims of the project

To assess the sustainability of different systems

Methods

Infrared spectroscopy, litterbag experiments, leachate sampling and analysis, use of stable isotopes, modelling