Sustainable agriculture: balance of nutrients for an integrated system of diagnosis

There is currently a major concern for environmental problems that may arise from misuse of fertilizers. From all the European and national institutions, in line with the principles of sustainable development, is urging farmers to make proper use of fertilizers and even, in the areas designated as 'Vulnerable', requires the implementation of a set of principles for action to minimize the environmental impact resulting from fertilization. While the Ministry of the environment, Rural and marine has established a formal methodology for analysis of suelo-agua - plant, there is a formal methodology of interpretation of these data and as a result of application of fertilizers for crops and agricultural regions. The Ministry itself, in its white paper, recognizes the 'lack of a general procedure to guide farmers on the rational use of the Subscriber'... through the 'better understanding of the characteristics of soils, establishing the recommendations of regional scope Subscriber...'. On the other hand, the autonomous communities have published the relevant codes of good agricultural practices, in areas where they are mandatory, limiting the application of nitrogenous fertilizers in forms and times determined in each case.

Also systems of integrated production (IP) that are being developed both at Community and national level, they contemplate as prior to the Subscriber, the analysis suelo-agua - practice plant in such a way that identified the needs of nutrients in each case. Despite the above, the final responsibility for the use of fertilizers rests on the farmers themselves. Historically, companies like Fertiberia has offered free of charge to its customers, technical advice through its agronomical service, consisting in the determination of appropriate doses of fertilizer to maximize their yields and minimize environmental risks using as a basis the results of the analysis of suelo-tierra - water made by its agronomic laboratory. With the idea to improve and automate this recommendation system, which came usually is conducted from the Agronomy service of Fertiberia, has developed a computer program in collaboration with the University Miguel Hernández of Elche, Alicante, Politécnica de Valencia and the Centre of soil science and biology Aplicada del Segura (Cebas-CSIC), which will make it possible to incorporate the experience of the Agronomy service of Fertiberia, the implementation of more innovative diagnostic systems in the field of statistical treatment and interpretation of the analyses of soil, water and vegetables, which has called for an important task of agronomic research that has been developed within the framework of this project and that day today is already extended to numerous crops. The implementation of this software solution based on the information and communication technologies will allow to make advice to Spanish farmers on an optimization of fertilization and contribute practical to a sustainable, environmentally friendly agriculture with environment and competitive economically.

The implementation of the it solution Siddra is based on the information and communication technologies, and will allow an advice to Spanish farmers on an optimization of fertilization and contribute practical to a sustainable, environmentally friendly agriculture with environment and competitive economicallyalways having as reference the analytical results.

The integration of these techniques, is based on establishing a reference to a nutrient value or a reference value for the relationship between one or more nutrients, according to the table of interpretation that we take. In such a way that when the laboratory analysis report of the concentrations of nutrients in soil or leaf, identify and quantify the nutritional imbalance of the plant and the program by default, we recommend the time optimum application, the way of doing this, the most appropriate chemical formulation and the optimum (minimum) provide mineral that we will have to be made to correct that possible nutritional imbalance and ensure us the expected harvest. In this way we ensure efficiency of the means of production in a sustainable manner, being respectful with the environment.

Siddra programme has been achieved the following objectives:

-Integration of the various systems of interpretation of plant nutrition, land analysis, analysis of water and foliar analysis.

-Integrate all the knowledge about fertilization that Fertiberia, has accumulated over the years, to be able to produce tables updated interpretation of the soil.

-Developing a methodology for the interpretation of the foliar analysis of different crops, beginning with the most common and continuing in years to come with other crops, and anyways by variety and pattern on woody crops both variety in arable cropsas well as to differentiate a culture both at the provincial or regional level.

-Establish a specific period for carrying out foliar sampling and that these are representative, in other words, with levels of nutrients more stable so that the diagnosis is totally reliable.

The programme aims to make improvements when it comes to a recommendation by Subscriber, that their results should be more precise to make decisions concerning the nutrition of the crop, thus assessing, optimizing and recommend the most sustainably for the environmentwith the consequent improvement of the profitability of farming studied.

To obtain the reference values have been made around 10,000 analyses of plants, soils and waters of the most important crops in major agricultural areas of Spain. The samples have been taken on those farms where crops have an optimal nutritional status and, therefore, can be taken as reference for assessing the status of the rest of the farms in the area. Analytical results are statistically dealt with the aim of obtaining some interpretative tables. The validity of these reference values shall be limited to the area in which the samples have been taken and the variety of the plant in question. This gives an idea of the accuracy of the system to make a recommendation, that we will have tables of interpretations specific or district for each crop and area, rather than rely on tables of a general nature as it has been doing on a regular basis.

This information along with the rest of considered variables (type of plant, climatology of the area, expected performance, cultural practices, etc.) are used to raise the equations that lead to obtain the amount of nutrients that are needed to bring in the Subscriber: nitrogen, phosphorus, potassium, (Mg, S, Ca, Na) secondary elements and microelements.

Another advantage of this project carried out by Fertiberia, is based on the dynamic that has the program, getting a steady stream of information to the system, with which we can extend our knowledge on other crops and areas, and to get perfect tables of interpretation which we have nowhave more data on those who carry out statistical studies that the system is capable of doing. In short, is achieved thanks to the program Siddra analyses requested by customers and those carried out by the research group that make up the technical team that make up the programme, delve a little deeper into knowledge of plant nutritionin order to make more efficient agricultural means of production, within the framework of sustainability.