On traditional small-scale mixed family farms with crop and livestock production, nutrients in livestock excreta were mostly utilised on the own land. With this recycling of the nutrients, the nutrient cycle was more or less closed and emissions resulting from excessive manure use or manure discharge were negligible. With the establishment of large specialised livestock production farms the nutrient cycle is often disrupted, because the excreta can no longer be used on the farms own land (landless farms or farms with insufficient crop land), or because a good manure and nutrient management is considered to be economically unfeasible. The livestock excreta are often discharged into watercourses or applied in excessive quantities to land close to the animal houses, which causes accumulation in the soil and high emissions into water and atmosphere. The problem is specially pronounnced on pig and poultry farms, which, contrary to cattle production, often grow none of the feed themselves.

The concept of area-wide integration between specialised livestock and crop farms (AWI), aims at re-establishing the balance between livestock and crop production on a regional level. One important step to achieve this is the contractual utilisation of manure from specialised livestock farms on surrounding crop farms. Thus, the nutrients and the organic matter in excreta are again recognised as resources which help to reduce the mineral fertiliser input of agriculture and the environmental impacts of livestock production. Nevertheless, such a practice needs a detailed planning and reliable tools and recommendations for farmers and extension officers. Reliable tools are also needed by public institutions to assess the environmental impacts through nutrient surpluses and emissions of agriculture.

The calculation model NuFluxAWI is such a tool which:

• quantifies the nutrient and heavy metal excretion on livestock (especially pig and poultry),
• quantifies the amount and the composition of different types of pig and poultry manure produced,
• quantifies the nutrient demand of crops,
• calculates the balance between nutrients in manure and other fertilisers on one hand, and nutrient demand of crops on the other hand
• allows fertliser plan calculations for distributing manure to different crops and complementing it with mineral fertilisers.
  

NuFluxAWI is designed in a way that allows user-friendly calculations on regional and farm level. Depending on the data available and the background of the user, the model calculations can be run with regional default values on livestock and crop production technique compiled by national experts or with farm-specific values. Special attention is paid to intensive livestock production systems. To allow the utilisation of the model in different countries and under various conditions, the program is equiped with functions that allow an easy translation of the whole program content, and the simple incorporation of new default value sheets. The program can be run on any PC equiped with MS-Excel (Office97 or higher). To guarantee a maximum of transparency and a minimum of misunderstandings, the same model calculations can be used by public institutions, aiming at an assessment of the nutrient impact situation (nutrient balance), as well as by the farmer or extension officer who want to work out a detailed fertilisation plan. Specific conditions can be set for specific results, though China and Thailand have been provided as examples.

Downloads

Country	Content	Zipped file
China	NuFlux Manual and Default Data Set: China
	NuFlux AWI China January 2002
Thailand	NuFlux Manual and Default Data Set: Thailand
	NuFlux AWI Thailand January 2002