Note: data for the years 2001-2017 are the average annual indicator of phosphate (above) concentration (mg P/l) and nitrogen (below) concentration ( mg NO3-N/l) was calculated. As for lakes and reservoirs, the average annual indicator of phosphate (left) concentration (mg P/l) and nitrogen (right) average annual indicator (mg NO3-N/ l) calculated as The number of monitoring points for both pollutants is 8.

Since 2012, there has been a downward trend in the average concentration of phosphate in rivers across the country. However, the average concentration was twice as high in the following years as compared to the previous years. The concentration in Ganja-Gazakh region and especially in Shirvan increased from 2009 to 2011. Concentrations in the Ganja-Gazakh zone continued to increase steadily after that. A slower but steady growth is observed for the Guba-Khachmaz region.

The average concentration of nitrate in rivers has decreased during the studied period and especially since 2011, reaching its lowest level since 2014. The trend is quite similar between different regions, but in previous years nitrogen concentration was higher in Ganja-Gazakh and Shirvan than in Guba-Khachmaz and Lankaran-Astara. The highest levels were observed in Nakhchivan, but this region was represented by only one monitoring site.

Phosphate concentration in lakes and water reservoirs increased significantly starting from 2009 and then decreased. The level of concentration has increased throughout the period, the concentrations have increased by 1.5 times in recent years compared to previous years.

Regarding nitrate, the concentration for lakes and reservoirs is different from that seen for rivers, where the lowest concentrations were observed at the beginning of the time series. Before the increase observed in the lakes, the average concentration increased somewhat sharply, but since 2009 it has halved. Still, current levels are nearly four times higher than in previous years.

What is the current situation of concentration of nutrients in groundwater of the Republic of Azerbaijan?

Description of the pointer

Concentrations of phosphates and nitrates in rivers and lakes (phosphate was used instead of total phosphorus in lakes)

Units

The concentration of phosphates and total phosphorus is expressed in mg P / liter, the concentration of nitrates is expressed in mg NO3-N / liter.

Justification

Rationale for indicator selection

Agriculture is widely developed in the country's river basins. As a result of the use of fertilizers in agricultural fields, nitrogen and phosphorus wastes into water bodies have a negative effect on aquatic flora and fauna and create certain problems related to the use of water for drinking water purposes.

Good environmental conditions related to the concentration of nutrients in surface waters are important to meet the requirements of national environmental legislation and related EU directives: Water Framework Directive, Urban Wastewater Treatment Directive.

Compared to other countries in the South Caucasus, Azerbaijan's water resources are limited and make up only 15 percent of all water resources in the region. The sources of surface water resources of the country are rivers, lakes, reservoirs and glaciers. Azerbaijan is a severely water-stressed country with limited water resources, with a long-term average annual water use index (WEI) of more than 53.1% (WEI = 78.4% in 2019). (See indicators C2 and C3 for more details).

There are 21 transboundary rivers in the country, and most of them are located in the Kura and Araz river basins. The basins of Kura and Araz rivers are located in three and four countries, respectively.

After joining the UNECE Helsinki Convention on the Protection and Use of Transboundary Watercourses and International Lakes, water quality control activities in the main transboundary rivers, the Kura and Araz rivers, have been established in accordance with international standards.

Given the level of water pollution that already exists in upstream countries, water quality monitoring in Azerbaijan is extremely important. For this purpose, analytical laboratories were established in Gazakh, Beylagan and Neftchala regions, the purpose of which is to carry out monitoring activities in Kura and Araz rivers and their cross-border branches.

Scientific references

• European Union Council Directive of 21 May 1991   - on urban waste water treatment
• Directive 2000/60/EC of the European Parliament and of the Council of 23 October 2000 establishing a framework for Community action in the field of water policy (Water Framework Directive) http://ec.europa.eu/environment/water/waterframework/index_en.html ;   
• UNECE Convention on the Protection and Use of Transboundary Watercourses and International Lakes (1992)

Current phosphate and nitrate concentrations were generally low in the river areas of Azerbaijan and slightly lower than the national maximum allowed concentrations (1.1 mg P/l and 10 mg NO3-N/l, respectively). In the Gazakh-Ganja and Shirvan regions, about 40% of the areas have a phosphate concentration in the range of 0.02-0.05 mg P / l. In case of increased phosphate concentration, special attention should be paid to these areas. Nitrate concentration was always below 0.2 mg NO3-N / l.

Although slightly higher than rivers, low nitrate concentrations were also found in lakes and reservoirs. The concentration of Lake Shabran and Lake Jandar was above 0.8 mg NO3-N/l, and only Jeyranbatan reservoir was below 0.2 mg NO3-N/l. For phosphate, the difference was greater, with 30% of stations above 0.1 mg P/l. This represents only three sites (Buyukshor, Lake Shabran and Lake Yasamal), but for these sites phosphate levels are high enough to cause eutrophication.

Methodology for calculating the indicator

After joining the UNECE Convention on the Protection and Use of Transboundary Watercourses and International Lakes, water quality control measures in the main transboundary rivers, the Kura and Araz rivers, have met international standards. Operational monitoring in both rivers was carried out according to the guidelines "Monitoring and assessment of transboundary watercourses and international lakes" developed by a group of qualified UN experts. Analytical research laboratories equipped with equipment for monitoring these rivers and their transboundary areas at the level of modern requirements were created in the Gazakh and Beylagan regions, taking into account that the Kura and Araz rivers pass through the neighboring states and are exposed to more pollution.

The monitoring program includes monitoring stations on 47 rivers and 10 lakes/reservoirs. Annual trends for each location are calculated by averaging the values ​​of individual samples per year. Aggregate data are calculated as the average of individual annual trends. Only time series completed after gap filling are included in the aggregate time series. This is to ensure that the aggregate data series are consistent, meaning that there are identical points throughout the time series. In this way, estimates are not based on actual changes in concentration and changes in the number of stations. Time series were calculated for the whole country and only for rivers (pooled for Kazakh-Ganja, Guba-Khachmaz, Lankaran-Astara, Shirvan and Nakhchivan) (1 station with only nitrate data).

For the analysis of the current situation, the monitoring stations were divided into different concentration classes based on the average level of the average annual concentrations for the years 2016-2017. All stations containing data from 2016-2017 were included in the analysis, regardless of the number of years for which data were obtained during the given time period. The results are divided by different regions.

Gap filling methodology

Gaps up to three years are filled by linear interpolation. The values ​​at the beginning and end of the time series are extrapolated by obtaining up to three years of the first or last values, respectively. Missing time series of more than three consecutive years during the time period are not included.

Methodological references

• ISO 5815-2: 2003   - Environmental protection and environmental management. Analytical control and monitoring. Water quality. Determination of biochemical oxygen consumption (BOTn) after N days. Part 2. A method applied without rinsing the samples.
• ISO 6777:1984   - Water quality - determination of nitrites. Molecular absorption spectrometric method. Determines the method for drinking, technical and waste water. A list of the effects of other substances on the outcome is provided in the Appendix. As standard nitrite solutions can be unstable, the concentration of these solutions should be checked by the given procedure.
• EEA, 2005.  Guide to the EEA core set of indicators. EEA Technical report No. 1/2005, ISBN 92-9167-757-4, Luxembourg.
• UNECE, 2018.  Guidelines for the Implementation of Environmental Indicators, Description of C10. Biochemical Oxygen Demand (BOT) and ammonium concentration in rivers.
• UNECE, 2018.  Guidelines for the Application of Environmental Indicators, Glossary - C10. Biochemical Oxygen Demand (BOT) and ammonium concentration in rivers.
• UNSD and UNEP, 2013.  Environmental Statistics Survey 2013. United Nations Statistics Division and United Nations Environment Programme, Environmental Statistics Survey 2013, Water Division.