Potential Use of Water Hyacinth for Wastewater Treatment in Serbia

1. BALWOIS 2006 Potential Use of Water Hyacinth (Eichhornia crassipes (Mart.) Solms.) for Wastewater Treatment in Serbia Nevena Nesic1, Ljubinko Jovanovic2 1Institute of Forestry, Belgrade 2Centre for Multidisciplinary Studies University of Belgrade Serbia & Montenegro

2. Serbia is facing the same problems in planning, management and conservation of waters as most countries of the World. • For relatively small country like Serbia dispose of water resources have a special significance. • A great deal of interest has been shown in Serbia for introduction of water hyacinth and construction of aquatic systems for wastewater treatment in last year.

3. Goal and Objective • To offer answers on some of the key questions • Can this tropical plant grow in Serbia? • Will it impose a threat to existing wetlands? • Is it efficient enough in removing different pollutants? • and many other.

4. Plant origin and Geographical distribution • South American aquatic macrophyte 40o 40o

5. Plant origin and Geographical distribution • First appearance outside of its home range was in North America at the end of 19th century (1884) • Today it’s widely distributed in south states of USA • Alabama • California • Florida • Louisiana • Texas • and others

6. Plant origin and Geographical distribution • About the same time it was spotted in Egypt where it invaded many African rivers and lakes such as Lake Victoria

7. Plant origin and Geographical distribution • Till then water hyacinth spread to countless tropical and subtropical countries usually with catastrophic socioeconomic and ecological consequences

8. Morphology of Water Hyacinth

9. Growth and Reproduction • Generative reproduction • Vegetativereproduction • Only 10 plants in just 8 months can produce population of 655,330 individuals. • Theoretically, by vegetative reproduction 1 plant can colonise water surface during 1 month by creating 8,191 new individuals.

10. Ecological factors • Heliophyte plant growing best in warm waters rich in macronutrients. • Optimal water temperature for growth is 28 -30oC • Optimal air temperature is 21-30 oC • It can not be grown in open where average winter temperature drops under 1 oC.

11. Hornsby Bend water hyacinth facility basin configuration, Austin,Texas

12. Efficiency of pollutant removal • Water hyacinth systemsrepresent the majority of aquatic plant systems that have been constructed. • They can remove organic matter, suspended materials, nutrients and heavy metals from wastewater with great efficiency. • Nitrogen 10 - 90 % • Phosphorus 35 - 80 % • BOD552 - 60% • Suspended materials 43 - 96% • Cd and other heavy metals 72-90 %

13. Costs of aquatic systems • Construction, operation, maintenance and monitoring costs of aquatic systems are quite high but in comparison to same costs of conventional treatment facilities they are still acceptable. • Total construction costs of water hyacinth systems range from 2,000,000 to 2,800,000 $. • Maintenance costs are about 550,000 $ per year.

14. ? Golden plant or The most notorious aquatic weed

15. Potentials in using water hyacinth • In regions where it can be found in abundance water hyacinth can be used: • As food for people because its leaves are rich in proteins and vitamin A • As fodder • As green fertilizer or as mulch, compost and ash in regenerating degraded soils • For removal of different pollutants from water

16. Potentials in using water hyacinth • Positive influence on fish populations in natural waters or on fish growing in artificial accumulations • As substitute of straw in substrate for mushroom growing • For energy production (briquettes or biogas) thereby combating tropical deforestation

17. Potentials in using water hyacinth • In settlements where water hyacinth has destroyed economy (fishing, river transport…) people can reorient to manufacturing • art paper, • crafts, • ropes, • furniture • and other things from water hyacinth • which will positively influence to reduction of unemployment and increase of income.

18. Constrains in using water hyacinth • Water hyacinth is sensitive to low temperatures • If aquatic systems with water hyacinth are built in colder climates it would be necessary to place them in the greenhouses. • Construction of greenhouses can have significant impact on the extent of construction costs. • Because of that it is presumed that it would be economically unjustified to build these alternative systems in regions where they can not operate in open the whole year.

19. Constrains in using water hyacinth • Exceptionally serious ecological problems

20. Constrains in using water hyacinth • Considerable economic damages in regions where it spreads uncontrolled, especially in communities whose main earnings come from fishing and tourism • It creates impenetrable barriers and prevent navigation. • It blocks drainage systems causing flooding or preventing withdrawal of floodwaters. • It blocks access to recreational areas and reduces values of waterfront properties. • It creates suitable environment for mosquitoes because it disrupts application of insecticides, drainage and water circulation.

21. Using water hyacinth in Serbia? • First constrain – incapability of adjusting to climatic conditions in Serbia • Plantation growing – not very appealing and not economically justified • Aquatic systems – greenhouse, low winter temperature, high construction costs, not very profitable

22. Using water hyacinth in Serbia? • Are described advantages of water hyacinth in tropics also its advantages in regions where it could not be found in abundance which will certainly be the case in Serbia? • Food and fodder – heavy metals • Fertilizer, mulch, compost and ashes – heavy metals • Substrate for mushroom growing – plenty of straw

23. Conclusion • In essence the biggest NO for introduction of Eichhornia crassipes (Mart.) Solms. in Serbia is the fact that this is one of the most invasive weeds in the world which have caused a lots of damages in areas where it was introduced.

24. Conclusion • It is necessary to be very careful with introduction of Eichhornia crassipes (Mart.) Solms. and construction of aquatic systems with water hyacinth in Serbia. • It would be best to carry out detailed studies about plant behaviour in our climate and real dangers that it can impose.

25. It is very important to point that there are over 45 aquatic plant species that can be successfully used for wastewater purification in Serbia. Most of these plants are autochthonous, fully acclimatised and which is more important they are not aquatic weeds.