1.2 Coordonnées des personnes-ressources et des institutions impliquées dans l'évaluation et la documentation de la Technologie

Nom du projet qui a facilité la documentation/ l'évaluation de la Technologie (si pertinent)

Book project: Making sense of research for sustainable land management (GLUES)

Nom du ou des institutions qui ont facilité la documentation/ l'évaluation de la Technologie (si pertinent)

Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB) - Allemagne

Nom du ou des institutions qui ont facilité la documentation/ l'évaluation de la Technologie (si pertinent)

Potsdam-Institut für Klimaforschung (PIK) - Allemagne

Nom du ou des institutions qui ont facilité la documentation/ l'évaluation de la Technologie (si pertinent)

Universität Hohenheim - Allemagne

Nom du ou des institutions qui ont facilité la documentation/ l'évaluation de la Technologie (si pertinent)

Technische Universität Berlin (Technische Universität Berlin) - Allemagne

Nom du ou des institutions qui ont facilité la documentation/ l'évaluation de la Technologie (si pertinent)

Hochschule für Technik und Wirtschaft Dresden (HTW Dresden) - Allemagne

1.3 Conditions relatives à l'utilisation par WOCAT des données documentées

Le compilateur et la(les) personne(s) ressource(s) acceptent les conditions relatives à l'utilisation par WOCAT des données documentées:

Oui

2.1 Courte description de la Technologie

Définition de la Technologie:

Water purification using macrophytes to treat effluent from fish farming.

2.2 Description détaillée de la Technologie

Description:

The “Green Liver System” uses aquatic plants, established in artificial wetlands, to remove, transfer, stabilize or eliminate pollutants in wastewater from fish farms. The use of large quantities of feed in aquaculture, along with the application of antibiotics, hormones and probiotics, has negative impacts on aquatic ecosystems due to the introduction of nitrogen, phosphorous and drug residues into the system. The Green Liver System is a form of phytoremediation (phyto = plant and remediate = correct) that uses a range of plants to decompose, extract, or hold contaminants present in soils and waters. This technology has been considered as an innovative alternative and a low cost option compared to others used in contaminated sites - like membrane bioreactors, upflow anaerobic sludge blanket (UASB), and others.

The plants selected for use in Green Liver System artificial wetlands depend on the pollutant to be removed. Research shows physiological differences between species, which need to be taken into account when planning wastewater treatments. Ideal plants for phytoremediation need: a) a fast growth rate; b) high biomass production; c) long rooting systems; d) easy maintenance/pruning; e) to be able to persists, and f) to have the ability to store trace metals within specific parts which can be later removed.

The Green Liver System uses aquatic macrophytes, which extract contaminants from the water, store them, or even metabolize them - transforming them into less toxic or harmless products. In the case of Eichhornia crassipes, most of the solids in suspension are removed by sedimentation or by adsorption in the root system. The dense coverage of these plants reduces the mixing effect of the wind, as well as minimizing thermal mixture. Shading by the plants restricts algal growth and the root system prevents horizontal movement of particulate material. In this way, particles are removed from the wastewater and microorganisms associated with the plants’ rhizosphere slowly decompose. Many organisms can be used in biodegradation: these include bacteria and fungi as well as plants, and the efficiency of one or the other depend, in many cases, on the molecule structure and of the presence of enzymes that are effective in degrading the pollutant.

The fish farm used as an example here is located on the margins of the Itaparica reservoir in Brazil. There are dozens of excavated tanks used to produce tilapia (Oreochromis niloticus) and “tambaqui” (Colossoma macropomum) fingerlings and juvenile fish. As well as these tanks, there are many net enclosures installed in the reservoir where the fishes are reared to maturity. Part of the wastewater from the excavated tanks is released into a stabilization lagoon, and the remainder goes to the Green Liver System. The effluent is enriched with spare feed, and excreta from the fish, which includes drug residues. If not treated, this may cause eutrophication because of its mineral richness. The Green Liver System consists of an excavated tank of 100m x 20m x 2m in size. The tank is subdivided into six parts: two planted to Eichhornia crassipes and four to Egeria densa. A mesh barrier stops fish from being flushed into the tank. Regular monitoring of the physical, chemical and biological parameters is required to control environmental fluctuations.

2.3 Photos de la Technologie

2.5 Pays/ région/ lieux où la Technologie a été appliquée et qui sont couverts par cette évaluation

2.6 Date de mise en œuvre de la Technologie

Si l'année précise est inconnue, indiquez la date approximative: :

• il y a moins de 10 ans (récemment)

2.7 Introduction de la Technologie

Spécifiez comment la Technologie a été introduite: :

• au cours d'expérimentations / de recherches

Commentaires (type de projet, etc.) :

Construction took place in 2013, building on earlier experiences of the principal scientist, for instance in South Korea.

3.1 Principal(aux) objectif(s) de la Technologie

• préserver l'écosystème

3.2 Type(s) actuel(s) d'utilisation des terres, là où la Technologie est appliquée

Commentaires:

Major land use problems (compiler’s opinion): The Itaparica reservoir was completed in 1988 to generate hydropower. About 40,000 people were compulsorily relocated. The construction of the reservoir had interrupted fish movement, leading to a shortage of fish, making aquaculture a viable and profitable alternative, and current law allows this. However excess feed and excreta of fish, partly containing drug residues, add nutrients and pollute water. ECONOMIC ASPECTS: The agricultural economy of this semi-arid region is characterized by pastoral activities, as well as the cultivation of crop species resistant to drought, such as cotton, corn (maize), beans, and cassava in humid areas. Irrigation from the reservoir was potentially possible but investments in aquaculture proved more profitable. In general, the commercial companies involved do not treat effluent, leading to pollution. Even though monitoring is mandatory, almost nobody does it, nor do they make substantial efforts to purify the effluent.

Major land use problems (land users’ perception): There are several conflicts over water and related land use in the region. Some people say the water quality in the reservoir is good (and use it directly for drinking), others report ill-health especially during times of low water levels. Commercial aquaculture primarily produces tilapia. Invariably, some tilapia escape from their net cages and take over from other local species. The hydroelectric company manages the reservoir according to national needs in electricity – thus sudden water level fluctuations are frequent. Commercial aquaculture and associated land use dominate the shoreline, preventing access for artisanal fishermen to their traditional fishing grounds.

Future (final) land use (after implementation of SLM Technology): Other: Ow: Waterways, drainage lines, ponds, dams
Constraints of transition land, fallow or sporadicall used by roaming livestock (mainly goats) (area in between the land-based aquaculture and the lake)

3.3 Informations complémentaires sur l'utilisation des terres

Approvisionnement en eau des terres sur lesquelles est appliquée la Technologie:

• mixte: pluvial-irrigué

Nombre de période de croissance par an: :

• 1

Précisez:

Longest growing period from month to month: all year due to tropical climate

3.4 Groupe de GDT auquel appartient la Technologie

• gestion des eaux de surface (sources, rivières, lacs, mers)
• gestion/ protection des zones humides

• Water purification

3.5 Diffusion de la Technologie

Commentaires:

Total area covered by the SLM Technology is 2 m2.
The reservoir is 100m long and 20 m wide, with a depth of 1.7 m, but the area may be larger depending on the volume of effluent to be treated. The whole area comprises the fish ponds.

3.6 Mesures de GDT constituant la Technologie

Commentaires:

Specification of other vegetative measures: macrophytes, different species
Type of vegetative measures: in blocks

3.7 Principaux types de dégradation des terres traités par la Technologie

Commentaires:

Main causes of degradation: deforestation / removal of natural vegetation (incl. forest fires) (slash-and-burn practices), over-exploitation of vegetation for domestic use (firewood and charcoal making), overgrazing (free roaming run-wild donkeys, and small ruminants), urbanisation and infrastructure development (construction works near to body bodies (not respecting conservation areas)), discharges (point contamination of water) (indiscriminate disposal of effluents; excrements, drugs and surplus feed from fishes in net-cages), over abstraction / excessive withdrawal of water (for irrigation, industry, etc.) (abstraction of water from the reservoir without prior registration, not holding water use permits), change in temperature (supposed to be climate change induced), change of seasonal rainfall (high variability in semi-arid regions rather normal; though rainfall appears to fall in shorter periods), droughts (recurrent droughts are "normal", they appear to last for longer periods), poverty / wealth (limited livelihood sources in the rather remote municipality), inputs and infrastructure: (roads, markets, distribution of water points, other, …) (spoilage and low quality), education, access to knowledge and support services (often little value attached to natural resources), war and conflicts (conflicts among two families; conflicts among indigenous and commercial users), governance / institutional (restricted enforcement of existing rules; clientelism)

Secondary causes of degradation: soil management, crop management (annual, perennial, tree/shrub), industrial activities and mining, release of airborne pollutants (urban/industry…), disturbance of water cycle (infiltration / runoff), Heavy / extreme rainfall (intensity/amounts), wind storms / dust storms, floods, other natural causes (avalanches, volcanic eruptions, mud flows, highly susceptible natural resources, extreme topography, etc.) specify, population pressure, land tenure, labour availability

3.8 Prévention, réduction de la dégradation ou réhabilitation des terres dégradées

Spécifiez l'objectif de la Technologie au regard de la dégradation des terres:

• réduire la dégradation des terres

4.1 Dessin technique de la Technologie

4.2 Spécification/ explications techniques du dessin technique

The constructed wetland termed a “Green Liver System” is 100m x 25m x 2.0m in size. It is divided into six parts (one third of the tank planted with Eichhornia crassipes the remainder with Egeria densa). The average outflow during the period was 1,800 m³/h. Point P1 is the catchment from the reservoir. Point P2 is the inlet that receives the discharge of effluent from 10 ponds with juvenile tilapia (Oreochromis niloticus). Point P3 is the stage after the treatment with Eichhornia crassipes. Point P4 is the stage of the treatment with Egeria densa. Point P5 is the outlet into a containment basin.

Location: Itacuruba. Pernambuco
Date: 2013

Technical knowledge required for field staff / advisors: high (It is a sophisticated system which requires close observation and monitoring. Site-specific adaptation might be necessary (for instance fencing to avoid goats entering the area).)
Technical knowledge required for land users: high (It is a sophisticated system which requires close observation and monitoring. It will be easier with some experience.)
Main technical functions: improvement of water quality, buffering / filtering water

In blocks
Vegetative material: O : other
Number of plants per (ha): 250000
Other species: Egeria densa; Eichhornia crassipes

Dam/ pan/ pond
Depth of ditches/pits/dams (m): 1.7
Width of ditches/pits/dams (m): 20
Length of ditches/pits/dams (m): 100

Wall/ barrier
Depth of ditches/pits/dams (m): 1.7
Width of ditches/pits/dams (m): ca 0.3
Length of ditches/pits/dams (m): ca 15

Construction material (other): tubes, valves
Specification of dams/ pans/ ponds: Capacity 3400m3
Dimensions of spillways: ca 100m

4.3 Informations générales sur le calcul des intrants et des coûts

Indiquez la monnaie utilisée pour le calcul des coûts:

• dollars US

Indiquer le taux de change du dollars en monnaie locale (si pertinent): 1 USD= :

3,17

4.4 Activités de mise en place/ d'établissement

	Activité	Type de mesures	Calendrier
1.	Digging the pit, stabilizing the walls	Végétale
2.	Fencing	Végétale
3.	Building separation walls	Végétale
4.	Planting macrophytes in place	Végétale

4.5 Coûts et intrants nécessaires à la mise en place

	Spécifiez les intrants	Unité	Quantité	Coûts par unité	Coût total par intrant	% des coût supporté par les exploitants des terres
Main d'œuvre	Construction		1,0	3000,0	3000,0
Main d'œuvre	Macrophyte installation		1,0	1900,0	1900,0
Equipements	Truck for removal of soil		1,0	125,0	125,0
Matériel végétal	Macrophytes					100,0
Matériel végétal	Wooden fence posts					100,0
Matériaux de construction	Walls/baffles (cement)		1,0	475,0	475,0
Matériaux de construction	Barbed wire		1,0	315,0	315,0
Matériaux de construction	Earthwork		1,0	250,0	250,0
Matériaux de construction	Tubular elements		1,0	30,0	30,0
Autre	Labour: Cutting fence posts		1,0	160,0	160,0
Autre	Labour: SUpervision		1,0	1000,0	1000,0
Coût total de mise en place de la Technologie					7255,0

4.6 Activités d'entretien/ récurrentes

	Activité	Type de mesures	Calendrier/ fréquence
1.	Exchange macrophytes	Végétale

4.7 Coûts et intrants nécessaires aux activités d'entretien/ récurrentes (par an)

	Spécifiez les intrants	Unité	Quantité	Coûts par unité	Coût total par intrant	% des coût supporté par les exploitants des terres
Main d'œuvre	Labour		1,0	3000,0	3000,0
Equipements	Nylon fabric		1,0	15,0	15,0
Matériel végétal	Macrophytes		1,0			100,0
Coût total d'entretien de la Technologie					3015,0

Commentaires:

Because of the tropical climate of Brazilian northeast there is a need to remove Eichhornia crassipes periodically because it grows very quickly as there is plenty nutrients and warm temperatures during all year. The cost of removal of the macrophytes is permanent and must be made monthly as the plant reaches adulthood it loses its capability in removing nutrients and gives it back to the water.

5.1 Climat

5.2 Topographie

5.3 Sols

Si disponible, joignez une description complète du sol ou précisez les informations disponibles, par ex., type de sol, pH/ acidité du sol, capacité d'échange cationique, azote, salinité, etc.

Soil fertility is low
Soil drainage/infiltration is poor
Soil water storage capacity is very low

5.4 Disponibilité et qualité de l'eau

5.5 Biodiversité

5.6 Caractéristiques des exploitants des terres appliquant la Technologie

Indiquez toute autre caractéristique pertinente des exploitants des terres:

Land users applying the Technology are mainly common / average land users
Population density: < 10 persons/km2
Annual population growth: 1% - 2%

5.7 Superficie moyenne des terres détenues ou louées par les exploitants appliquant la Technologie

5.8 Propriété foncière, droits d’utilisation des terres et de l'eau

Propriété foncière:

• individu, sans titre de propriété
• individu, avec titre de propriété

Droits d’utilisation des terres:

• individuel

• needs official registration and permission; heavy water use has a price

• needs official registration and permission; heavy water use has a price

5.9 Accès aux services et aux infrastructures

6.1 Impacts sur site que la Technologie a montrés

Impacts socio-économiques

Disponibilité et qualité de l'eau

Revenus et coûts

Autres impacts socio-économiques

Impacts socioculturels

Impacts écologiques

Cycle de l'eau/ ruissellement

Sols

Autres impacts écologiques

6.4 Analyse coûts-bénéfices

Quels sont les bénéfices comparativement aux coûts de mise en place (du point de vue des exploitants des terres)?

Quels sont les bénéfices comparativement aux coûts d'entretien récurrents (du point de vue des exploitants des terres)?

6.5 Adoption de la Technologie

Commentaires:

There is a little trend towards spontaneous adoption of the Technology. A broad adoption is not yet expectable at this stage of experimental analysis and testing. Few people did already express their interest.

6.7 Points forts/ avantages/ possibilités de la Technologie

Points forts/ avantages/ possibilités du point de vue de l'exploitant des terres
If the environmental authority increases controls of how effluent from aquaculture ponds is handled (checking pollution and nutrient loads in the effluent which is usually returned to the reservoir without any treatment), the technology would help compliance with existing rules.
The technology can be constructed using locally available material.

Points forts/ avantages/ possibilités du point de vue du compilateur ou d'une autre personne ressource clé
Water purification is realized by using natural processes.
Among the advantages of adopting the Green Liver technology are the low costs, the speed of construction and it's relatively easy operation.

6.8 Faiblesses/ inconvénients/ risques de la Technologie et moyens de les surmonter

Faiblesses/ inconvénients/ risques du point de vue de l’exploitant des terres	Comment peuvent-ils être surmontés?
Additional manual labour increases costs (and hinders adoption)	The more people use such techniques, for instance due to improved environmental monitoring and fines imposed, the more such extra expenditure will be accepted as regular running costs.
The management of the system is not simple. Many different and unexpected disturbances can occur. Experience and close, constant watch out is needed.	Exchange of experience among users would facilitate its management. An updated list of threats could be helpful.

Faiblesses/ inconvénients/ risques du point de vue du compilateur ou d'une autre personne ressource clé	Comment peuvent-ils être surmontés?
From time to time the macrophytes have to be removed, tubes may need cleaning and the system needs to be set up again. Sometimes, the removal of almost all water may be indicated. Major maintenance can cause peak labour needs. Manual labour required to monitor the system on a regular basis, and perform maintenance according to needs. Depending on the number and size of Green Liver Systems in action, caring for them can be a full-time job.	The maintenance costs have to be well budgeted in the overall planning of costs and benefits of the related productive units.
The disposal of the removed macrophytes is still a problem to be solved. If the macrophytes have accumulated high levels of toxins, the biomass cannot be used for compost making or livestock feeding.	The removed macrophytes should be analysed for their pollutant content. A biodigester could be the solution to the disposal of contaminated biomass, generating energy for the productive unit and possibly for the local population too.

7.1 Méthodes/ sources d'information

7.2 Références des publications disponibles

Titre, auteur, année, ISBN:

Pflugmacher, S., Kühn, S., Lee, S.-H., Choi, J.-W., Baik, S., Kwon, K.-S., Contardo-Jara, V., 2015. Green Liver Systems® for water purification: Using the phytoremediation potential of aquatic macrophytes for the removal of different cyanobacterial toxins from water.

Disponible à partir d'où? Coût?

AJPS 06 (09), 1607–1618. doi:10.4236/ajps.2015.69161.

Titre, auteur, année, ISBN:

Nimptsch, J., Wiegand, C., Pflugmacher, S., 2008. Cyanobacterial toxin elimination via bioaccumulation of MC-LR in aquatic macrophytes: An application of the “Green Liver Concept”

Disponible à partir d'où? Coût?

Environ. Sci. Technol. 42 (22), 8552–8557. doi:10.1021/es8010404.