Fertilizer consumption: main information sources on national level and data quality assurance

1. Fertilizer consumption: main information sources on national level and data quality assurance Prepared by Barbara Kutin Slatnar and Enisa Lojović Hadžihasanović, SORS, Department for Agricultural, Forestry and Fishing Statistics

2. The presentation will present the following issue only: Introduction • UNECE environmentalindicator • »FertilizerConsumption« is consistedfrom: • consumptionof mineral fertilizers in agriculture • data on theuseofmanure • theconsumptionof mineral fertilizers in agriculture • Regularannualsurvey (from 1995) • Regularbiannualsurvey (from 2006) To understand quality and burden aspects of data collection mean to have a good understanding of the structural aspects of agriculture in a country. Therefore, initially we present the basic characteristics of agriculture in Slovenia. SORS, Department for Agricultural, Forestry and Fishing Statistics

3. Slovenia in Figures According to final data of the 2010 Agriculture Census in Slovenia were 74,646 agricultural holdings. They used 474,432 hectares of agricultural area and bred 421,553 LSU (livestock units). In 2010 almost 79% of agricultural holdings in Slovenia bred livestock. An average agricultural holding thus used 6.4 hectares of agricultural area and bred 5.6 LSU. Use of total area on agricultural holdings, Slovenia, 2010 Use of UAA, Slovenia, 2010 High proportion of permanent grassland SORS, Department for Agricultural, Forestry and Fishing Statistics

4. Slovenia in Figures Total labour input into agriculture in Slovenia, expressed in annual work units (AWU), was 77,012 AWU or 0.16 AWU per hectare of utilised agricultural area in 2010. Structure of UAA, Slovenia, 2010 High proportion of AH with small areas of UAA SORS,DepartmentforAgricultural, Forestry and Fishing Statistics

5. Regular annual survey 1/2 From 1995 on Data sources: • Data on mineral fertilisers and plant nutrients used in enterprises, companies and co-operatives during the growing season and their stocks on 31 December of the current year are collected with annual reports filled in by all enterprises, companies and co-operatives involved in crop production. • Data on import and sale of mineral fertilisersfor crop production and data on plant nutrients in individual mineral fertilisers are collected with the annual statistical report directly from import enterprises. • Data on domestic production of mineral fertilisers are taken over from the Manufacturing Statistics Department. Mineral fertilisers are classified by the PRODCOM list • Data on export of mineral fertilisers are taken over from the External Trade Statistics Department. Mineral fertilisers are classified by the Combined Nomenclature SORS, Department for Agricultural, Forestry and Fishing Statistics

6. Regular annual survey 2/2 Main variables: • mass of imported mineral fertilisers, • mass of sold imported mineral fertilisers on the domestic market for the agricultural purposes • production of mineral fertilisers in Slovenia • usage of mineral fertilisers in agricultural enterprises • stocks of mineral fertilisers in trade and agricultural enterprises. Main statistics: • total mass of used / available mineral fertilisers for agricultural plant production by type of mineral fertilisers (CN classification) and by NPK plant nutrients • total mass of used / available NPK plant nutrients per hectare of utilised agricultural areas. Publishing- Annually: • First Release. • Web site of the SORS (SI-STAT database) • Statistical Yearbook SORS, Department for Agricultural, Forestry and Fishing Statistics

7. Regularbiannual survey 1/2 From 2006 on Data sources: • CATI: we take over the sample of the statistical survey on »Crop  production, Slovenia« in the reference year. The sample design is stratified simple random sampling. • Data on the consumption of mineral fertilizers used in agricultural enterprises for  the production of most important crops were collected in the regular annual survey  »Consumption of mineral fertilizers«. In the survey »Consumption of mineral  fertilizers by crops« these data were combined with the family farms data. Data representativity • Obtained data are representative only at the level of Slovenia. SORS, Department for Agricultural, Forestry and Fishing Statistics

8. Regularbiannual survey 2/2 The main facts which affect the accuracy of the results of the use of mineral fertilizers by crops: - Sample size, which depends on the homogeneity of phenomena according to the geographical distribution; - Response rate: 68 – 79% - Size of the occurrence of particular crop or group of crops; - Assessment of the use of data sources (completenes and accuracy) for each group of agricultural area by crops - quality preparation of the sampling frame; - Taking into account differences between sown and harvested area of ​​a crop (which area we considering in the “NPK use per area” calculation?). SORS, Department for Agricultural, Forestry and Fishing Statistics

9. Data quality assurance - The regular annual survey Advantages of such methodology are: • Easy and fast way to collect data • High response rate • Some other sources could be used for data control, including websites of trade enterprises. But there is also some disadvantages: • This data represent still the available mass of mineral fertiliser usage in agriculture. • Separation of mineral fertilisers by their usage is still very hard work. • Mistakes in CN codes could seriously influence on the final data result SORS, Department for Agricultural, Forestry and Fishing Statistics

10. Data quality assurance - The regular annual survey Concerning last two mentioned disadvantages we pay special attention to microdata statistical control of all data sources used in survey. All data are processed with additional logical controls (aspect of agriculture): • Control of agricultural data with external trade data, according to the company and type of fertilizer (CN - Combined Nomenclature). In this way we control data entry and errors in the CN tariff (information on plant nutrients help us to determine whether fertilizer is properly encoded by CN). • Control of agricultural data with last year's data by company and by type of fertilizer. In this way we control the particular details of the sale to cover last year's stocks f.e. • Plant nutrients - control of the existing classification (updated every year) used in the statistical survey; use of Internet as additional source of information; direct contacts with manufacturers. • - Control of basic activitie of the enterprises (NACE nomenclature and public information available on Internet) to determine the correct purpose of use of fertilizers. SORS, Department for Agricultural, Forestry and Fishing Statistics

11. Data quality assurance - The regular biannual survey Remember: main facts which affect the accuracy of the results of the use of mineral fertilizers by crops + additionaldata control elements: • Logical controls as a part of the aplication for data entry (CATI): • we have available detailed data on area by crops and by agricultural holdings • In the process of data collection we have available three different possibilities for fertiliser data input: by trade name, by group of fertiliser and by name raised by respondent. • For the calculation of the use  of mineral fertilisers per crops only the use of more than 20 kg/ha of N or P2O5 or K2O is justified and  was taken into account • For all agricultural holdings with more than 2 hectares of arable land we insert (acording to defined rules) data on consumption of mineral fertilizers • Comparishonoftheagregatesofthissurveywiththeresultsofregularannualsurvey. SORS, Department for Agricultural, Forestry and Fishing Statistics

12. Conclusions 1/2 • We recognise our system of data collection on the consumption of mineral fertilizers in agriculture described as good - so the frequency of data collection, as well as links between the annual survey of the areas sown and binnual survey on consumption of mineral fertilizers by crops. • We believe that obtaining data on consumption of mineral fertilizers by crops is sufficiently frequent on several years, but at the same time have to be established an annual balance sheet data collection system on available mineral fertilisers for agriculture. We also believe that the sample survey data can be interpreted only on plant nutrients level. • A sample survey on consumption of mineral fertilizers by crops is expensive and very demanding, which also reflects the fragmentation of agriculture in Slovenia. SORS, Department for Agricultural, Forestry and Fishing Statistics

13. Conclusions 2/2 With regard to future activities in the provision of internationally comparable and quality data are expected in particular the following: • Completion of the FAO-questionnaire structure: currently it is not provideing data entry on plant nutrients from the fertilizer imports. Already, thecountrycan enter themanufacturingdatacalculations per unit of plant nutrients. The important thing is that we have the possibility to entry the data on plant nutrients (own calculations) for all input data sets needed for calculation (also imports). This is particularly important for countries that use the major part of imported fertilizers. • Data on manure: we believe that is sufficient to estimate it (use of coefficients). Therefore, it is important to develop (on internationallevel) especiallythemethodologyforestimatinguseoflivestockmanure in thefuture. • In the future, we expect the most consistent requests for information from the FAO and EUROSTAT, because countries have different requirements for a double load. On the other hand different data lead to possible isunderstandingof the data • We also hope that will be let to national statistics flexibility in terms of methodology and organization of surveys, because this will be the only way to choose such a methodology, which will provide high quality information. SORS, Department for Agricultural, Forestry and Fishing Statistics

14. Links to published data and metadata SI-STAT data portal http://pxweb.stat.si/pxweb/Database/Environment/15_agriculture_fishing/07_consumption/01_15170_fertilizers/01_15170_fertilizers.asp The Methodological Explanations http://www.stat.si/eng/metodologija_pojasnila.asp?pod=15 The Quality Report http://www.stat.si/doc/metodologija/kakovost/SPK_KME_PMG_KME_UMG.pdf Contacts Statistical Office of the Republic of SloveniaDepartment of Agriculture, Forestry, Fishing and Hunting StatisticsAddress: Litostrojska cesta 54, SI-1000 LjubljanaTel: + 386 1 2340 760E-mail: enisa.lojovic@gov.si, barbara.kutin@gov.si SORS, Department for Agricultural, Forestry and Fishing Statistics