Systemic modelling of soil functions under the impact of agricultural management

The increasing demand for food and bio-energy gives need to optimize soil productivity, while securing other soil functions such as nutrient cycling and buffer capacity, carbon storage, biological activity, and water filter and storage. Mechanistic simulation models are an essential tool to fully understand and predict the complex interactions between physical, biological and chemical processes of soil with those functions, as well as the feedbacks between these functions.We developed a systemic soil model to simulate the impact of different management options and changing climate on the named soil functions by integrating them within a simplified system. The model operates on a 1d soil profile consisting of dynamic nodes, which may represent the different soil horizons, and integrates different processes including dynamic water distribution, soil organic matter turnover, crop growth, nitrogen cycling, and root growth.We present the main features of our model by simulating crop growth under various climatic scenarios on different soil types including management strategies affecting the soil structure. We show the relevance of soil structure for the main soil functions and discuss different model outcome variables as possible measures for these functions.Further, we discuss ongoing model extensions, especially regarding the integration of biological processes, and possible applications.

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Biological processes in modelling soil functions – a balancing act between too complex and too simple

10.5194/egusphere-egu21-7458 ◽

2021 ◽

Author(s):

Sara König ◽

Ulrich Weller ◽

Thomas Reitz ◽

Bibiana Betancur-Corredor ◽

Birgit Lang ◽

...

Keyword(s):

Nutrient Cycling ◽

Microbial Activity ◽

Community Dynamics ◽

Spatial Scales ◽

Simulation Models ◽

Microbial Processes ◽

Biological Processes ◽

Soil Functions ◽

Management Options ◽

The Impact

Mechanistic simulation models are an essential tool for predicting soil functions such as nutrient cycling, water filtering and storage, productivity and carbon storage as well as the complex interactions between these functions. Most soil functions are driven or affected by soil organisms. Yet, biological processes are often neglected in soil function models or implicitly described by rate parameters. This can be explained by the high complexity of the soil ecosystem with its dynamic and heterogeneous environment, and by the range of temporal and spatial scales these processes are taking place at. On the other hand, the technical capabilities to explore microbial activity and communities in soil has greatly improved, resulting in new possibilities to understand soil microbial processes on various scales.However, to integrate such biological processes in soil modelling, we need to find the right level of detail. Here, we present a systemic soil model approach to simulate the impact of different management options and changing climate on soil functions integrating biological activity on the profile scale. We use stoichiometric considerations to simulate microbial processes involved in different soil functions without explicitly describing community dynamics or functional groups. With this approach we are able to mechanistically describe microbial activity and its impact on the turnover of organic matter and nutrient cycling as driven by agricultural soil management.Further, we discuss general challenges and ongoing developments to additionally consider, e.g., microbe-fauna-interactions or microbial feedback with soil structure dynamics.

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Brief history and future of animal simulation models for science and application

Animal Production Science ◽

10.1071/an14650 ◽

2014 ◽

Vol 54 (12) ◽

pp. 1883 ◽

Cited By ~ 23

Author(s):

J. L. Black

Keyword(s):

Animal Models ◽

Real Time ◽

Dynamic Models ◽

Management Strategies ◽

Simulation Models ◽

Real Time Control ◽

Livestock Farming ◽

Animal Metabolism ◽

The Impact ◽

Further Development

Mathematical equations have been used to add quantitative rigour to the description of animal systems for the last 100 years. Initially, simple equations were used to describe the growth of animals or their parts and to predict nutrient requirements for different livestock species. The advent of computers led to development of complex multi-equation, dynamic models of animal metabolism and of the interaction between animals and their environment. An understanding was developed about how animal systems could be integrated in models to obtain the most realistic prediction of observations and allow accurate predictions of as yet unobserved events. Animal models have been used to illustrate how well animal systems are understood and to identify areas requiring further research. Many animal models have been developed with the aim of evaluating alternative management strategies within animal enterprises. Several important gaps in current animal models requiring further development are identified: including a more mechanistic representation of the control of feed intake; inclusion of methyl-donor requirements and simulation of the methionine cycle; plus a more mechanistic representation of disease and the impact of microbial loads under production environments. Reasons are identified why few animal models have been used for day-to-day decision making on farm. In the future, animal simulation models are envisaged to function as real-time control of systems within animal enterprises to optimise animal productivity, carcass quality, health, welfare and to maximise profit. Further development will be required for the integration of models that run real time in enterprise management systems adopting precision livestock farming technologies.

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DairyMod and EcoMod: biophysical pasture-simulation models for Australia and New Zealand

Australian Journal of Experimental Agriculture ◽

10.1071/ea07133 ◽

2008 ◽

Vol 48 (5) ◽

pp. 621 ◽

Cited By ~ 106

Author(s):

I. R. Johnson ◽

D. F. Chapman ◽

V. O. Snow ◽

R. J. Eckard ◽

A. J. Parsons ◽

...

Keyword(s):

New Zealand ◽

Nutrient Dynamics ◽

Irrigation Management ◽

Management Strategies ◽

Simulation Models ◽

Nutrient Status ◽

Pasture Management ◽

Management Options ◽

Recent Developments ◽

Fertiliser Application

DairyMod and EcoMod, which are biophysical pasture-simulation models for Australian and New Zealand grazing systems, are described. Each model has a common underlying biophysical structure, with the main differences being in their available management options. The third model in this group is the SGS Pasture Model, which has been previously described, and these models are referred to collectively as ‘the model’. The model includes modules for pasture growth and utilisation by grazing animals, water and nutrient dynamics, animal physiology and production and a range of options for pasture management, irrigation and fertiliser application. Up to 100 independent paddocks can be defined to represent spatial variation within a notional farm. Paddocks can have different soil types, nutrient status, pasture species, fertiliser and irrigation management, but are subject to the same weather. Management options include commonly used rotational grazing management strategies and continuous grazing with fixed or variable stock numbers. A cutting regime simulates calculation of seasonal pasture growth rates. The focus of the present paper is on recent developments to the management routines and nutrient dynamics, including organic matter, inorganic nutrients, leaching and gaseous nitrogen losses, and greenhouse gases. Some model applications are presented and the role of the model in research projects is discussed.

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Online modelling of water distribution systems: a UK case study

Drinking Water Engineering and Science ◽

10.5194/dwes-3-21-2010 ◽

2010 ◽

Vol 3 (1) ◽

pp. 21-27 ◽

Cited By ~ 37

Author(s):

J. Machell ◽

S. R. Mounce ◽

J. B. Boxall

Keyword(s):

Distribution Systems ◽

Water Distribution ◽

Data Transfer ◽

Simulation Models ◽

Distribution Networks ◽

Water Supply Systems ◽

Full Potential ◽

Operational Conditions ◽

The Impact

Abstract. Hydraulic simulation models of water distribution networks are routinely used for operational investigations and network design purposes. However, their full potential is often never realised because, in the majority of cases, they have been calibrated with data collected manually from the field during a single historic time period and, as such, reflect the network operational conditions that were prevalent at that time, and they are then applied as part of a reactive, desktop investigation. In order to use a hydraulic model to assist proactive distribution network management its element asset information must be up to date and it should be able to access current network information to drive simulations. Historically this advance has been restricted by the high cost of collecting and transferring the necessary field measurements. However, recent innovation and cost reductions associated with data transfer is resulting in collection of data from increasing numbers of sensors in water supply systems, and automatic transfer of the data to point of use. This means engineers potentially have access to a constant stream of current network data that enables a new era of "on-line" modelling that can be used to continually assess standards of service compliance for pressure and reduce the impact of network events, such as mains bursts, on customers. A case study is presented here that shows how an online modelling system can give timely warning of changes from normal network operation, providing capacity to minimise customer impact.

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Simulation of legume-cereal systems using APSIM

Australian Journal of Agricultural Research ◽

10.1071/a97070 ◽

1998 ◽

Vol 49 (3) ◽

pp. 317 ◽

Cited By ~ 37

Author(s):

M. E. Probert ◽

P. S. Carberry ◽

R. L. McCown ◽

J. E. Turpin

Keyword(s):

Cropping Systems ◽

Management Strategies ◽

Simulation Models ◽

Cereal Crops ◽

Status Report ◽

Management Options ◽

Modelling Framework ◽

Stylosanthes Hamata ◽

Scenario Analyses ◽

Simulation Scenario

A major issue for the sustainability of cropping systems is the maintenance of soil fertility and especially the supply of nitrogen to cereal crops. Choice of appropriate management strategies, including the role of legumes, is problematic, especially where climatic variation is large. Simulation models provide the means of extrapolation from the site- and season-specific bounds of experimental data to permit scenario analyses that can explore alternative management options. This paper is a status report on the capabilities of the APSIM modelling framework to simulate legume-cereal systems. APSIM deals with water and nitrogen constraints to crop growth and is well suited to the task of modelling whole systems involving crop rotations. The components that are not yet fully developed are modules for growing the legume crops and coupling these with the module describing the dynamics of soil organic matter to obtain sensible predictions of nitrogen supply to subsequent crops. Evidence is provided that those parts of the system that can be represented by current APSIM modules are predicted satisfactorily. The closest approach to a whole system that has been simulated to date is grass or legume (Stylosanthes hamata cv. Verano) leys followed by crops of maize or sorghum grown in experiments at Katherine, NT. Predictions of the yields of the leys and the cereal crops, especially the benefit from the legume leys to a second crop, were sufficiently close to measured yields to suggest that there are good prospects for developing useful models of other systems involving legumes and cereals. A simulation scenario exploring a chickpea-wheat system demonstrates how models can be used to analyse both productivity and sustainability aspects of the system.

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Modelling the impact of poaching on metapopulation viability for data-limited species

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2015-0508 ◽

2017 ◽

Vol 74 (6) ◽

pp. 894-906 ◽

Cited By ~ 2

Author(s):

Abbey E. Camaclang ◽

Janelle M.R. Curtis ◽

Ilona Naujokaitis-Lewis ◽

Mark S. Poesch ◽

Marten A. Koops

Keyword(s):

Management Strategies ◽

Simulation Models ◽

Sensitivity Analyses ◽

Future Research ◽

Spatially Explicit ◽

Barkley Sound ◽

Spatially Explicit Population Model ◽

Future Research Directions ◽

Explicit Simulation ◽

The Impact

We developed a spatially explicit simulation model of poaching behaviour to quantify the relative influence of the intensity, frequency, and spatial distribution of poaching on metapopulation viability. We integrated our model of poaching with a stochastic, habitat-based, spatially explicit population model, applied it to examine the impact of poaching on northern abalone (Haliotis kamtschatkana) metapopulation dynamics in Barkley Sound, British Columbia, Canada, and quantified model sensitivity to input parameters. While demographic parameters remained important in predicting extinction probabilities for northern abalone, our simulations indicate that the odds of extinction are twice as high when populations are subjected to poaching. Viability was influenced by poaching variables that affect the total number of individuals removed. Of these, poaching mortality was the most influential in predicting metapopulation viability, with each 0.1 increase in mortality rate resulting in 22.6% increase in the odds of extinction. By contrast, the location and spatial correlation of events were less important predictors of viability. When data are limited, simulation models of poaching combined with sensitivity analyses can be useful in informing management strategies and future research directions.

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Evaluating Soil functions based on modeling under the impact of land use

10.5194/egusphere-egu2020-18436 ◽

2020 ◽

Author(s):

Ulrich Weller ◽

Birgit Lang ◽

Stefanie Mayer ◽

Bastian Stößel ◽

Hans-Jörg Vogel ◽

...

Keyword(s):

Management Strategies ◽

Economic Assessment ◽

Soil Processes ◽

Climate Scenarios ◽

Soil Functions ◽

Development Tools ◽

Per Se ◽

Comprehensive Modeling ◽

The Impact

While the change of soil functions under different management is important in the evaluation of long term strategies in agriculture, they are often difficult to be quantified. The obstacles are measurement problems on one hand, and on the other hand predictions for new management strategies and changing climate scenarios require estimates for yet unknown conditions. Comprehensive modeling of soil processes provides a road to both: Soil properties and processes that are per se difficult to measure can be included in a model to derive suitable indicators for soil unions. In this way, also, predicitons in the future for different climate scenarios and management strategies are possible.In this presentation we give definitions for a limited set of indicators to quantify the most important soil functions in terms of both the current soil state and the soils&#8217; potential to fulfill these functions. This includes the production of biomass, storage of carbon, storage and filtering of ground water, nutrient cycling, and habitat for biodiversity.The quantitative evaluation of soil functions byel based indicators and their dynamics facilitates further socio-economic assessment and the development tools for governance.

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Stimulated Effect of Organic and Inorganically Originated Transitory Nitrogen Sources on the Nutrient Concentration, Uptake and Production of Hybrid Maize

Cercetari Agronomice in Moldova ◽

10.2478/cerce-2014-0027 ◽

2014 ◽

Vol 47 (3) ◽

pp. 57-69

Author(s):

M. Waseem ◽

M. Tahir ◽

H.F. Bakhat ◽

I. Khan

Keyword(s):

Soil Structure ◽

Nutrient Concentration ◽

Poultry Manure ◽

Nitrogen Sources ◽

Research Area ◽

Soil Productivity ◽

Farm Yard Manure ◽

Hybrid Maize ◽

The Impact

Abstract Soil productivity one of the essential factors which enhanced either through adding the chemical fertilizer or by incorporation of organic sources of nutrients to the soil. Regardless by the used of imbalanced fertilizer without the application of organic manure and without seeking knowledge of crops and fertility classification of soil causes to much hazards such as deterioration of soil structure, soil and water pollution etc. Two years field experiment was carried out to check the impact of transitory nitrogen sources on the nutrient concentration, uptake and production of hybrid maize at the Agronomic Research Area, University of Agriculture Faisalabad, Pakistan, during the year 2008-2009. Treatments included two hybrids: H1 (Pioneer-30Y87) and H2 (Pioneer-31R88) with six nitrogen sources each, which included at the rate of S0: control (0) kg N ha-1, S1: chemical source (urea) 250 kg N ha-1, S2: poultry manure (PM) 9.6 t ha-1, S3: farm yard manure (FYM) 17.8 t ha-1, S4: pressmud of sugarcane (PMS) 8.5 t ha-1 and S5: compost (C) 10.0 t ha-1. Finding concluded that changing effect of nitrogen sources on both maize hybrid was found to be non significant during 2008-2009 while grain yield was significant during both years. Maximum nutrient concentration, uptake and yield were observed with nitrogen source S1: chemical source (urea) 250 kg N ha-1 during 2008-2009 as compared to other nitrogen sources and minimum was found in control (0) kg N ha-1, respectively. Interaction among hybrid and nitrogen sources was found to be non significant.

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Online modelling of water distribution systems: a UK case study

Drinking Water Engineering and Science Discussions ◽

10.5194/dwesd-2-279-2009 ◽

2009 ◽

Vol 2 (2) ◽

pp. 279-294 ◽

Cited By ~ 3

Author(s):

J. Machell ◽

S. R. Mounce ◽

J. B. Boxall

Keyword(s):

Distribution Systems ◽

Water Distribution ◽

Data Transfer ◽

Simulation Models ◽

Distribution Networks ◽

Water Supply Systems ◽

Full Potential ◽

Operational Conditions ◽

The Impact

Abstract. Hydraulic simulation models of water distribution networks are routinely used for operational investigations and network design purposes. However, their full potential is often never realised because, in the majority of cases, they have been calibrated with data collected manually from the field during a single historic time period and, as such, reflect the network operational conditions that were prevalent at that time, and they are then applied as part of a reactive, desktop investigation. In order to use a hydraulic model to assist proactive distribution network management its element asset information must be up to date and it should be able to access current network information to drive simulations. Historically this advance has been restricted by the high cost of collecting and transferring the necessary field measurements. However, recent innovation and cost reductions associated with data transfer is resulting in collection of data from increasing numbers of sensors in water supply systems, and automatic transfer of the data to point of use. This means engineers potentially have access to a constant stream of current network data that enables a new era of "online" modelling that can be used to continually assess standards of service compliance for pressure and reduce the impact of network events, such as mains bursts, on customers. A case study is presented here that shows how an online modelling system can give timely warning of changes from normal network operation, providing capacity to minimise customer impact.

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Agricultural drought monitoring and management at sub district level in Telangana

MAUSAM ◽

10.54302/mausam.v67i1.1190 ◽

2021 ◽

Vol 67 (1) ◽

pp. 259-266

Author(s):

D. RAJI REDDY ◽

G. SREENIVAS

Keyword(s):

Management Strategies ◽

Crop Growth ◽

District Level ◽

Agricultural Drought ◽

Close Monitoring ◽

Rainfed Agriculture ◽

Growth Development ◽

The Impact ◽

Sw Monsoon ◽

Onset Of Monsoon

The weather or climate is considered as an important natural resource and basic input for better planning of crop and cropping system in agriculture particularly rainfed environments. Every plant process, related with growth, development and yield of a crop and each of in-season and off-season farm operations depends on weather. Amongst the various weather elements, temperatures, radiation and rainfall play crucial role in deciding the crop growth, development and yield levels. Precipitation is one of the important weather factors being responsible for atmospheric and soil moisture and therefore has more agricultural importance, especially in rainfed agriculture. Rainfed crops like jowar, maize, groundnut, greengram, blackgram and sunflower and one water-intensive crop like rice are mainly affected owing to drought. The drought conditions occur due to failure of South West Monsoon, delay in arrival of SW monsoon, and break monsoon conditions or early cessation of SW monsoon. Rainfed agriculture in India depends on onset of monsoon and the rainfall distribution during crop growth season. The amount of rainfall and the time of onset of monsoon decides the type of the crop to be grown. The timely onset and well distribution of monsoon rain in the month of June and July decides the area coverage of rainfed crops. Any deviation in the onset and distribution of southwest monsoon rainfall causes huge impact on agriculture and its dependent activities. Close monitoring of progress of monsoon and distribution of rainfall and its impact on sowing of rainfed crops is essential at sub district level to suggest time to time crop management strategies thereby to minimize the impact of aberrant seasonal conditions. In this paper a monitoring of drought at national, state and sub district (Mandal) level using indices like MAI, WRSI etc. were presented. Management strategies to reduce the impact of drought like optimum time of sowing, strategic irrigation, crop calendar, contingency crop planning etc. were discussed. Agromet advisories for communication of real time weather information for benefit of farming community were presented.

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