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

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

Faculty of Agriculture, University of Peradeniya, Sri Lanka (AGRI.PDN) - Sri Lanka

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

1.4 Déclaration sur la durabilité de la Technologie décrite

Est-ce que la Technologie décrite ici pose problème par rapport à la dégradation des terres, de telle sorte qu'elle ne peut pas être déclarée comme étant une technologie de gestion durable des terres?

Non

Commentaires:

Urea is the type of nitrogen fertilizer available in Sri Lanka. Urea is readily soluble in water and hydrolyses to ammonia which in turn is converted to nitrate by microorganisms. Nitrate can be lost by leaching, volatilization, and denitrification in paddy fields. However, slow release fertilizer (SRF) releases the N in urea slowly to the soil and allows efficient uptake by the crop at the right time. Hence, it reduces the negative environmental impacts associated with N losses and also maintains adequate productivity in rice cultivation. In addition, this technology reduces CO2 emissions from rice husks to the atmosphere.

2.1 Courte description de la Technologie

Définition de la Technologie:

Rice husks, a waste product generated in rice mills, can release its carbon as a greenhouse gas (GHG) to the atmosphere through burning or decomposition. Converting it into biochar and intercalating (filled) with urea can produce a slow-release nitrogen (N) fertiliser that improves N-use efficiency while minimizing GHG emissions.

2.2 Description détaillée de la Technologie

Description:

Rice husks are often considered as a waste, and its carbon is released to the atmosphere as carbon dioxide (CO2) which is a greenhouse gas (GHG) through either decomposition or burning as a biofuel. However, rice husks can be converted into biochar – where its carbon is stable - with a large number of micro and sub-micron size pores in a honeycomb-like structure. Rice husk biochar was produced using an improved batch pyrolizer, “Kunthaniya”, at a temperature of between 450°C and 650°C. Pore spaces in rice husk biochar can be intercalated (filled) with urea and then, slow-release fertilizer (SRF) pellets can be produced through the use of a suitable biodegradable binder. This SRF has found to be more efficient in improving the N-use efficiency, hence the urea requirement of paddy fields in Sri Lanka can be reduced by about 25%, further contributing to environment sustainability. It has been well documented that biochar can improve soil physical, chemical and biological properties in a sustainable manner. This process is a contribution to creative recycling of agricultural waste.
The SRF technology was evaluated against current farmer practice in rice cultivated area in Mahakanumulla village, Anuradhapura district, Sri Lanka. The area belongs to the Dry Zone of Sri Lanka (mean annual rainfall <1750mm). Rice is cultivated during two seasons, yala (May-September) and maha (December – February): the yala season is generally drier. Farmers rely on irrigation water supplied from a small village tank. The SRF was transported to farmers’ fields and applied at 2 weeks (@ 100 kg/ha), at 4 weeks (@ 170 kg/ha) and 7 weeks (@ 145 kg/ha) after direct seeding.
Farmers indicated that the granule size was large and light, hence they had some concerns about even distribution of fertilizer. They perceive that plants receive N slowly compared to granular urea - suggesting the slow releasing nature of the new technology. They did not observe any yield difference. Obtaining rice husks in large quantities from rice mills to produce biochar can sometimes be difficult in some areas of the country due to competition for use in the poultry industry. Some farmers may be discouraged to implement this technology due to lack of knowledge: this can be overcome through extension officers operating at field level.

This new technology qualifies as a sustainable land management practice in number of ways. First it increases N-use efficiency in paddy fields, second it reduces the urea requirement by 25% while sustaining productivity, third it recycles agricultural wastes in paddy fields, fourth, repeated application of SRF improves soil fertility through rice husk biochar, and finally it reduces GHG emissions.

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

Indiquez l'année de mise en œuvre:

2021

2.7 Introduction de la Technologie

Spécifiez comment la Technologie a été introduite: :

• au cours d'expérimentations / de recherches
• par le biais de projets/ d'interventions extérieures

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

• améliorer la production
• réduire, prévenir, restaurer les terres dégradées
• atténuer le changement climatique et ses impacts
• créer un impact économique positif
• créer un impact social positif

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

Les divers types d'utilisation des terres au sein du même unité de terrain: :

Non

3.3 Est-ce que l’utilisation des terres a changé en raison de la mise en œuvre de la Technologie ?

Est-ce que l’utilisation des terres a changé en raison de la mise en œuvre de la Technologie ?

• Non (Passez à la question 3.4)

3.4 Approvisionnement en eau

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

• mixte: pluvial-irrigué

Commentaires:

Rice farmers in Mahakanumulla mainly depend on irrigation water supplied from a small tank located above the rice fields. However, farmers do not irrigate rice fields if they receive adequate rainfall. But, increasingly, farmers depend on irrigation water due to decreasing rainfall during the growing season.

3.5 Groupe de GDT auquel appartient la Technologie

• gestion intégrée de la fertilité des sols
• gestion des déchets/ gestion des eaux usées

3.6 Mesures de GDT constituant la Technologie

Commentaires:

Application of SRF to the crop at the required growth stages to improve the soil fertility and, thus, crop productivity.

3.7 Principaux types de dégradation des terres traités par la Technologie

Commentaires:

The SRF technology improves soil fertility by reducing nitrogen (N) loss from the soil due to leaching. And it also reduces accumulation of excess N in surface and ground water bodies, preventing water pollution.

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

Commentaires:

The use of conventional N fertilizers to cultivate rice for a long period of time causes higher N losses from the soil and results a potential risk of environment pollution. Application as an SRF reduces the losses of N from the soil, increases crop nutrient uptake and increases crop productivity. The reduced losses mitigate soil fertility degradation and deterioration of water quality.

4.1 Dessin technique de la Technologie

4.2 Informations générales sur le calcul des intrants et des coûts

Spécifiez la manière dont les coûts et les intrants ont été calculés:

• par superficie de la Technologie

autre/ monnaie nationale (précisez):

LKR

Indiquez le taux de change des USD en devise locale, le cas échéant (p.ex. 1 USD = 79.9 réal brésilien): 1 USD = :

275,0

4.3 Activités de mise en place/ d'établissement

	Activité	Calendrier des activités (saisonnier)
1.	Collection of paddy husk from rice milling stations	2 months before cultivation
2.	Pyrolyzing of paddy husk using a pyrolizer or a kunthani	6 weeks before cultivation
3.	Mixing with urea, ERP and other ingredients and pelletizing	4 weeks before cultivation
4.	Drying the pellets (SRF)	2 weeks before cultivation
5.	Packing and transporting SRF to the rice fields	1 week before cultivation

Commentaires:

One of the major raw materials to produce SRF is rice husks and it can be supplied from rice milling stations, generally available year-round. However, there is competition for rice husks in the market because of demand from the poultry industry. Hence, finding rice husks is sometimes difficult in some areas of the country.

4.4 Coûts et intrants nécessaires à la mise en place

	Spécifiez les intrants	Unité	Quantité	Coûts par unité	Coût total par intrant	% du coût supporté par les exploitants des terres
Main d'œuvre	Manufacturing SRF	Labour days	2,5	1500,0	3750,0
Engrais et biocides	Urea	kg	200,0	270,0	54000,0
Matériaux de construction	Binding materials 1	kg	10,0	25,0	250,0
Matériaux de construction	Binding materials 2	kg	10,0	250,0	2500,0
Matériaux de construction	Rice husk biochar	kg	200,0	50,0	10000,0
Coût total de mise en place de la Technologie					70500,0
Coût total de mise en place de la Technologie en dollars américains (USD)					256,36

Si le coût n'est pas pris en charge à 100% par l'exploitant des terres, indiquez qui a financé le coût restant:

Project funded by the National Research Council of Sri Lanka (Grant No. : NRC TO-16/07)

Commentaires:

SRF was given to the farmer, free, for application. The cost of SRF was borne by the project funded by the National Research Council of Sri Lanka (Grant No. : NRC TO-16/07)

4.5 Activités d'entretien/ récurrentes

	Activité	Calendrier/ fréquence
1.	Application of first dose of SRF	2 weeks after direct seeding of rice
2.	Application of second dose of SRF	4 weeks after direct seeding of rice
3.	Application of third dose of SRF	7 weeks after direct seeding of rice

Commentaires:

Application of correct amount of SRF at the correct growth stage of the rice crop is important for efficient uptake of N to the crop and reduce losses.

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

	Spécifiez les intrants	Unité	Quantité	Coûts par unité	Coût total par intrant	% du coût supporté par les exploitants des terres
Main d'œuvre	Labour for SRF application	Labour days	3,0	1500,0	4500,0	100,0
Coût total d'entretien de la Technologie					4500,0
Coût total d'entretien de la Technologie en dollars américains (USD)					16,36

4.7 Facteurs les plus importants affectant les coûts

Décrivez les facteurs les plus importants affectant les coûts :

Labour availability and finding raw materials are the major factors that affect the cost.

5.1 Climat

5.2 Topographie

Indiquez si la Technologie est spécifiquement appliquée dans des:

• non pertinent

Commentaires et précisions supplémentaires sur la topographie:

The altitude of the area is 112m. An undulating pattern of topography is a distinct feature of this landscape. The rice is cultivated mainly in the valley area of the catena and other upland crops are cultivated in the crest area of the catena.

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.

Rice growing soils of the Mahakanumulla area are classified as Alfisols (Typic endoaquaalf). The soil is poorly drained. The pH of the soil is in the neutral range (6.05-7.23). Soil EC (55.5-143.0 µs/cm, 1:2.5 soil:water) values did not show any occurrence of soil salinity. Av. P content of the soil (Olsen P) was low for rice growth (<5 mg/kg) and ranged from 2.9-3.5 mg/kg. Av. K content of the soils was medium to high for rice growth and ranged from 61.3-99 mg/kg.

5.4 Disponibilité et qualité de l'eau

La salinité de l'eau est-elle un problème? :

Non

La zone est-elle inondée?

Non

Commentaires et précisions supplémentaires sur la qualité et la quantité d'eau:

The amount of water supplied through the irrigation is limited during the dry season (yala). The water quality is affected by soil macro-nutrients (N, P, K) added as fertilizers to the soil. Due to the undulating topography of the landscape, those soil nutrients can wash-off from higher positions to lower positions due to surface runoff and leaching into the ground water and accumulating in the water bodies in the lower positions of the catena.

5.5 Biodiversité

Commentaires et précisions supplémentaires sur la biodiversité:

Number of different tree species, wild animals, birds, insects and aquatic life can be observed around Mahakanumulla village. Forest patches can be identified mostly around the small tank, and those areas are habitats for multiple wild animals and birds.

5.6 Caractéristiques des exploitants des terres appliquant la Technologie

Indiquez toute autre caractéristique pertinente des exploitants des terres:

Most of the land users are dependent on full time rice farming. But some land users use rice farming as a secondary source of income and do other jobs in the city. Most of the younger generation in the village are migrating for jobs in the cities.

5.7 Superficie moyenne des terres utilisées par les exploitants des terres appliquant la Technologie

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

Propriété foncière:

• individu, avec titre de propriété

Droits d’utilisation des terres:

• individuel

Droits d’utilisation de l’eau:

• communautaire (organisé)

Est-ce que les droits d'utilisation des terres sont fondés sur un système juridique traditionnel?

Non

5.9 Accès aux services et aux infrastructures

Commentaires:

The villagers of Mahaknumulla have access for most of the resources like infrastructure and energy/electricity/fuel. But most of the villagers/landusers complain about technical assistant/support for agricultural practices, finding markets for their produce and availability of good quality drinking water. The villagers go to nearby shops to buy day-to-day needs, but they have to go to the town, which is 8-10km away, for other services such as health and financial services.

6.1 Impacts sur site que la Technologie a montrés

Impacts socio-économiques

Production

Disponibilité et qualité de l'eau

Revenus et coûts

Impacts socioculturels

Impacts écologiques

Cycle de l'eau/ ruissellement

Sols

Biodiversité: végétale, animale

Réduction des risques de catastrophe et des risques climatiques

Précisez l'évaluation des impacts sur site (sous forme de mesures):

Plant growth parameters and yield

6.2 Impacts hors site que la Technologie a montrés

6.3 Exposition et sensibilité de la Technologie aux changements progressifs et aux évènements extrêmes/catastrophes liés au climat (telles que perçues par les exploitants des terres)

Changements climatiques progressifs

Changements climatiques progressifs

	Saison	Augmentation ou diminution	Comment la Technologie fait-elle face à cela?
températures annuelles		augmente	pas connu
précipitations annuelles		décroît	pas connu

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

• cas isolés/ expérimentaux

Si disponible, quantifiez (nombre de ménages et/ou superficie couverte):

5 farmers/households

6.6 Adaptation

La Technologie a-t-elle été récemment modifiée pour s'adapter à l'évolution des conditions?

Non

6.7 Points forts/ avantages/ possibilités de la Technologie

Points forts/ avantages/ possibilités du point de vue de l'exploitant des terres
This technology uses less chemical fertilizer and therefore it is good for their health and environment
This technology gives better crop growth and slightly higher yield
Biochar could improve the fertility of the soil

Points forts/ avantages/ possibilités du point de vue du compilateur ou d'une autre personne ressource clé
SRF reduces the N losses from the soil and allows the rice crop to uptake N effectively from soil at required growth stages. Efficient N uptake promotes the crop growth and increase the productivity.
Reduced N losses of SRF directly influence the water quality by reducing the losses of N through surface runoff and leaching and avoid accumulation in water bodies at the lower positions of the landscape.
Rice husks, which is are good source of C, are utilized for SRF production; hence it promotes C sequestration as it is added back to the soil as biochar. It improves the soil organic carbon pool and promotes carbon sequestration in soil.
Utilizing rice husks by returning back to the rice fields is an effective solution for rice waste management.
If the SRF production technology can be transferred to farmers, their societies can produce the SRF by themselves from the wastes generated in small scale rice mills.

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 cost despite reduced chemical fertilizer	increased crop yields can partially compensate this. They can produce their own SRF if the production technology is transferred to them
Uneven distribution of nitrogen in the field	Changing the water management practices that have been currently adopted by farmers

Faiblesses/ inconvénients/ risques du point de vue du compilateur ou d'une autre personne ressource clé	Comment peuvent-ils être surmontés?
The raw materials need to be formulated accurately to get the benefits of the technology. Hence, technical knowledge and experience is required when preparing SRF.	Proper guidance and technical support from the beginning to the end of the process is essential. This can be achieved through educating and training extension officers to teach and disseminate knowledge for farmers.

7.1 Méthodes/ sources d'information

7.2 Références des publications disponibles

Titre, auteur, année, ISBN:

Preparation of Biochar as a Soil Amendment from Rice Husk and Corn Cob by Slow Pyrolysis Process, S.T. Munasinghe, R.S. Dharmakeerthi, P. Weerasinghe and L.G.S. Madusanka, ISSN 0041-3224

Disponible à partir d'où? Coût?

Tropical Agriculturist Journal

Titre, auteur, année, ISBN:

Changes in Structural and Chemical Properties of Rice Husk Biochar Co-pyrolysed with Eppawala Rock Phosphate under Different Temperatures, D.K.R.P.L. Dissanayake, R.S. Dharmakeerthi, A.K. Karunarathna and W.S. Dandeniya, ISSN: 2706-0233

Disponible à partir d'où? Coût?

Tropical Agricultural Research Journal

Titre, auteur, année, ISBN:

Biochar Based Slow-Release Urea Fertilizer: Production and Assessing the Effects on Growth of Lowland Rice and Nitrogen Dynamics in an Alfisol, M.K.N.W. Jayarathna, R.S. Dharmakeerthi and W.M.U.K. Rathnayaka, ISSN: 2706-0233

Disponible à partir d'où? Coût?

Tropical Agricultural Research Journal

7.3 Liens vers les informations pertinentes en ligne

Titre/ description:

Changes in Structural and Chemical Properties of Rice Husk Biochar Co-pyrolysed with Eppawala Rock Phosphate under Different Temperatures

URL:

http://192.248.43.153/bitstream/1/3160/2/PGIATAR_30_1_19.pdf

Titre/ description:

Biochar Based Slow-Release Urea Fertilizer: Production and Assessing the Effects on Growth of Lowland Rice and Nitrogen Dynamics in an Alfisol

URL:

https://tar.sljol.info/articles/abstract/10.4038/tar.v32i2.8464/

7.4 Observations d'ordre général

The WOCAT questionnaire on SLM technologies covers all the aspects that can affect on the sustainability of natural and human environment.