Anne Mette Lykke | Aarhus University (original) (raw)
Papers by Anne Mette Lykke
La zone sud-soudanienne du Burkina Faso est soumise comme l'ensemble du pays à une péjoration du ... more La zone sud-soudanienne du Burkina Faso est soumise comme l'ensemble du pays à une péjoration du climat et une dégradation accélérée de ses ressources naturelles, surtout du sol et de la végétation. Des technologies de conservation des eaux et des sols comme le zaï et les cordons pierreux ont été éprouvées et adoptées dans les zones plus sèches du Nord. Dans cette étude, il s'est agi de tester les dispositifs expérimentés en vue de restaurer les potentialités d'un sol ferrugineux tropical lessivé induré situé entre les isohyètes 900 mm et 1100 mm. Un dispositif en blocs de Fisher complètement randomisé a été installé. Les observations ont porté sur la croissance et l'évaluation du rendement du sorgho (Sorgum bicolor). Des échantillons de sol ont été prélevés, puis quelques paramètres chimiques ont été déterminés au laboratoire. Des mesures d'infiltration ont été faites à l'aide de l'infiltromètre à double anneaux. Les résultats montrent que les traitements « zaï » et « zaï plus cordons pierreux » sont transférables en zone sud-soudanienne. Ils ont permis un meilleur développement du sorgho et une augmentation des rendements en grains de 6 et 4 fois respectivement par rapport au témoin. Les propriétés chimiques du sol ont connu des amélioration sensibles et le pH a atteint une valeur avoisinant 6,5 dans les poquets de zaï. Les deux techniques ont contribué de manière significative à améliorer le coefficient d'infiltration de l'eau dans le sol.
RÉSUMÉ Le présent chapitre aborde les méthodes de calcul de la biomasse et du carbone des arbres.... more RÉSUMÉ Le présent chapitre aborde les méthodes de calcul de la biomasse et du carbone des arbres. Les différentes étapes de ce calcul sont dans un premier temps le choix de l'approche à utiliser (utilisation des équations allométriques ou générales), ensuite la détermination de la densité du bois de chaque espèce d'arbre et la définition des réservoirs de carbone à considérer. Il faut ensuite calculer la moyenne de la biomasse vivante et morte de chaque strate au sein des placettes, supposer la fraction de carbone dans les arbres puis calculer le carbone à partir de la biomasse, calculer également l'incertitude et enfin convertir le carbone en dioxyde de carbone. L'estimation de la biomasse et du carbone a pris une importance croissante dans le monde. L'augmentation de la quantité du carbone au niveau des forêts va permettre l'établissement des petites exploitations agroforestières et des projets REDD +. ABSTRACT This chapter presents the methods used to calculate tree biomass and carbon stocking. The different steps include choosing an approach (allometric equations or general equation), finding wood densities for each tree species. It is necessary to define which carbon pools to include, calculate the average live and dead biomass of plots in each stratum, make an assumption about the fraction of carbon in the trees, calculate carbon from biomass, calculate uncertainty, and convert from carbon to carbon dioxide. The estimation of biomass and carbon has gained increasing importance. With the increasing number of forest carbon, smallholder agroforestry and REDD+ projects being established.
All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.
Acknowledgements We wish to thank all SUN and BIOTA project members participating in the West Afr... more Acknowledgements We wish to thank all SUN and BIOTA project members participating in the West African Vegetation Data Network workshops held at the Research Institute Senckenberg in Frankfurt in December 2007 and at the Université de Oua-gadougou in November 2008. The SUN project is funded by the Commission of the European Community (INCO-031685).
Flora et Vegetatio Sudano-Sambesica, 2014
Knowledge about useful plants and their various applications in West Africa is scattered over man... more Knowledge about useful plants and their various applications in West Africa is scattered over many publications and often in form of grey literature difficult to access. Several online-databases compile large scale information from these sources and provide comprehensive summarized descriptions of plant usages. Our aim is to additionally build up a database (UseDa) for primary ethnobotanical interview data. Thus, quantitative data can be extracted and synthesized and data sets can be treated according to different research questions analyzing for example uses in specific areas, of different ethnic groups or user groups, which is essential for practical applications on a local level. In this article we give an overview on the technical structure and the content of the database and discuss at the end the possible output for practical application. The database was set up in the frame of the EU-funded Project UNDESERT.
The Biodiversity of African Plants, 1996
L’etude est realisee dans le Parc national du W du Niger situe au sud-ouest du pays. L’objectif p... more L’etude est realisee dans le Parc national du W du Niger situe au sud-ouest du pays. L’objectif principal est de faire un etat des lieux de differents types de vegetation et de les decrire. La methode classique de numerisation sur ecran sur la base des images satellites Landsat ETM+ 2005 est utilisee. La classification effectuee a ete validee sur la base des releves phytoecologiques du terrain. Ainsi, la typologie realisee a permis de definir 19 classes d’occupation des terres. Les formations vegetales les mieux representees sont les savanes, les brousses tachetees et la vegetation clairsemee sur affleurement rocheux avec respectivement 41, 19 et 16 %. La carte de vegetation issue de cette etude pourra servir de support aux actions d’amenagement de cette aire protegee. Elle sera aussi une situation de reference pour l’analyse de la dynamique des ecosystemes de la zone.
Global Ecology and Biogeography, 2020
This is an open access article under the terms of the Creat ive Commo ns Attri bution License, wh... more This is an open access article under the terms of the Creat ive Commo ns Attri bution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
International Journal of Biological and Chemical Sciences, 2020
Cowpea is an important source of food and income for the populations of sub-Saharan Africa in gen... more Cowpea is an important source of food and income for the populations of sub-Saharan Africa in general and particularly in West Africa. However, farmers face storage and conservation problems. During storage in granaries, cowpea seeds are attacked by insects causing decreased grain weight and quality and sometimes a loss of germination capacity. Traditionally, farmers have used aromatic plants to limit insect damage. The aim of the present study is to test the insecticidal potential of three aromatic plants (Ocimum americanum L., Cymbopogon schoenanthus L. and Hyptis suaveolens Poit.). Cowpea seeds were mixed with increasing amounts of powder from each of the three plants and stored in plastic boxes for 10 month. The results showed that the number of defective seeds varied according to the treatment. O. americanum was the most efficient; the smallest effective dose of powder was 12%. For C. schoenanthus and H. suaveolens, the smallest effective doses were 16% and 18% respectively. Wi...
Journal of Agriculture and Environmental Sciences, 2017
International Journal of Environmental Health Research, 2020
The purpose of this paper is twofold: to explore the factors influencing the emergence and growth... more The purpose of this paper is twofold: to explore the factors influencing the emergence and growth of informal e-waste activities and to examine workers' motivation for involvement in informal e-waste activities. Semi-structured interviews and observations among actors in the recently established Dagomba-Line e-waste site in Kumasi, Ghana were employed to gather relevant data. Emergence and growth of e-waste activities are largely influenced by spatial, political, socio-cultural and economic factors. The reuse and open disposal of e-waste are the common practices due to the cost of transportation to a final disposal site. Similar to findings at the well-established Agbogbloshie e-waste site, also in Ghana, scavengers are found at the bottom of the e-waste financial ladder. The major motivating factor for engaging in e-waste handling is poverty. Additionally, some respondents mentioned the lucrative nature of the activity, landlessness, and peer influence as a motivation. The results showed that younger workers (below 35 years) were more likely to be engaged in the activity for reasons of peer influence and poverty and major source of livelihood . The paper recommends that policy and planning should reflect ways of delivering and creating stable socio-economic conditions that promote an inclusive and sustainable development.
Journal of Arid Environments, 2020
Abstract Reliable estimates of carbon stocks for drylands are constrained by a limited number of ... more Abstract Reliable estimates of carbon stocks for drylands are constrained by a limited number of biomass models for predicting accurately the biomass of dominant tree and shrub species. In this study, 119 trees with a diameter at breast height (dbh) between 3.82 and 45.48 cm were destructively sampled to evaluate aboveground biomass (AGB) allocation and prediction for four dryland species (Senegalia dudgeonii, Senegalia gourmaensis, Vachellia nilotica and Vachellia tortilis) commonly found in the Sudanian and Sahelian zones of Burkina Faso. Biomass allocation to leaf, branch and stem was examined using a classmometric analysis. Allometric equations relating biomass to dbh alone, and to dbh in combination with height and/or crown area were developed with and without consideration of the additivity property. Branches stored the largest (up to 90%) proportion of AGB. For three of the species, the branch mass fraction increased with increasing tree size at the expense of stem and leaf mass fractions. The statistical evaluations of the selected additive and non-additive models were satisfactory with no severe deficiencies. Diagnostics of model performance revealed that non-additive models performed better than additive models. The biomass models developed can be used for improved quantification of carbon stock and dynamics in dry savanna ecosystems.
BOIS & FORETS DES TROPIQUES, 2015
Les plantes oléagineuses locales offrent des usages multiples et constituent une source de revenu... more Les plantes oléagineuses locales offrent des usages multiples et constituent une source de revenus pour les communau- tés rurales. L’objectif de notre étude est de comprendre les perceptions et les savoirs des populations de la province du Kénédougou (Burkina Faso) concer- nant ces plantes et leurs huiles. La mé- thodologie utilisée est une combinaison de l’approche participative sociale et d’enquêtes ethnobotaniques. Au total,336 personnes ont été interrogées au sein de quatre groupes communautaires (Toussian, Siamou, Bolon et Peulh) à tra- vers 14 villages. Les résultats révèlent 11 plantes oléagineuses connues, parmi lesquelles quatre représentent 94 % de l’ensemble des citations. Le savoir sur les espèces ne varie significativement que selon l’âge (Χ2 = 8,11 ; p = 0,0173). Ce sont les adultes et les aînés qui dis- posent plus de savoir sur ces espèces. Les femmes sont les principales déten- trices des savoirs sur les techniques d’ex- traction des huiles et leur transformat...
Heliyon, 2019
Native tree foods contribute to food and nutrition security, health and income generation in sub-... more Native tree foods contribute to food and nutrition security, health and income generation in sub-Saharan Africa. However, the specific contribution of native tree foods to nutrition is poorly documented in science and often not acknowledged in poverty reduction strategies. This review gives an overview on the content of carbohydrates, proteins, fat, fibers, ash and dry matter of 98 native food tree species from sub-Saharan Africa. Data were grouped according to the food providing organ (seeds, fruits and leaves). In general, seeds had high content of fat, protein and dry matter; while leaves had high content of protein and ash. There was no significant difference between the three organs on the content of fibers and carbohydrate. Some tree foods species were good sources to provide carbohydrates, proteins, fat, fibers, ash and dry matter.
International Journal of Biological and Chemical Sciences, 2019
La zone sud-soudanienne du Burkina Faso est soumise comme l'ensemble du pays à une péjoration du ... more La zone sud-soudanienne du Burkina Faso est soumise comme l'ensemble du pays à une péjoration du climat et une dégradation accélérée de ses ressources naturelles, surtout du sol et de la végétation. Des technologies de conservation des eaux et des sols comme le zaï et les cordons pierreux ont été éprouvées et adoptées dans les zones plus sèches du Nord. Dans cette étude, il s'est agi de tester les dispositifs expérimentés en vue de restaurer les potentialités d'un sol ferrugineux tropical lessivé induré situé entre les isohyètes 900 mm et 1100 mm. Un dispositif en blocs de Fisher complètement randomisé a été installé. Les observations ont porté sur la croissance et l'évaluation du rendement du sorgho (Sorgum bicolor). Des échantillons de sol ont été prélevés, puis quelques paramètres chimiques ont été déterminés au laboratoire. Des mesures d'infiltration ont été faites à l'aide de l'infiltromètre à double anneaux. Les résultats montrent que les traitements « zaï » et « zaï plus cordons pierreux » sont transférables en zone sud-soudanienne. Ils ont permis un meilleur développement du sorgho et une augmentation des rendements en grains de 6 et 4 fois respectivement par rapport au témoin. Les propriétés chimiques du sol ont connu des amélioration sensibles et le pH a atteint une valeur avoisinant 6,5 dans les poquets de zaï. Les deux techniques ont contribué de manière significative à améliorer le coefficient d'infiltration de l'eau dans le sol.
RÉSUMÉ Le présent chapitre aborde les méthodes de calcul de la biomasse et du carbone des arbres.... more RÉSUMÉ Le présent chapitre aborde les méthodes de calcul de la biomasse et du carbone des arbres. Les différentes étapes de ce calcul sont dans un premier temps le choix de l'approche à utiliser (utilisation des équations allométriques ou générales), ensuite la détermination de la densité du bois de chaque espèce d'arbre et la définition des réservoirs de carbone à considérer. Il faut ensuite calculer la moyenne de la biomasse vivante et morte de chaque strate au sein des placettes, supposer la fraction de carbone dans les arbres puis calculer le carbone à partir de la biomasse, calculer également l'incertitude et enfin convertir le carbone en dioxyde de carbone. L'estimation de la biomasse et du carbone a pris une importance croissante dans le monde. L'augmentation de la quantité du carbone au niveau des forêts va permettre l'établissement des petites exploitations agroforestières et des projets REDD +. ABSTRACT This chapter presents the methods used to calculate tree biomass and carbon stocking. The different steps include choosing an approach (allometric equations or general equation), finding wood densities for each tree species. It is necessary to define which carbon pools to include, calculate the average live and dead biomass of plots in each stratum, make an assumption about the fraction of carbon in the trees, calculate carbon from biomass, calculate uncertainty, and convert from carbon to carbon dioxide. The estimation of biomass and carbon has gained increasing importance. With the increasing number of forest carbon, smallholder agroforestry and REDD+ projects being established.
All in-text references underlined in blue are linked to publications on ResearchGate, letting you... more All in-text references underlined in blue are linked to publications on ResearchGate, letting you access and read them immediately.
Acknowledgements We wish to thank all SUN and BIOTA project members participating in the West Afr... more Acknowledgements We wish to thank all SUN and BIOTA project members participating in the West African Vegetation Data Network workshops held at the Research Institute Senckenberg in Frankfurt in December 2007 and at the Université de Oua-gadougou in November 2008. The SUN project is funded by the Commission of the European Community (INCO-031685).
Flora et Vegetatio Sudano-Sambesica, 2014
Knowledge about useful plants and their various applications in West Africa is scattered over man... more Knowledge about useful plants and their various applications in West Africa is scattered over many publications and often in form of grey literature difficult to access. Several online-databases compile large scale information from these sources and provide comprehensive summarized descriptions of plant usages. Our aim is to additionally build up a database (UseDa) for primary ethnobotanical interview data. Thus, quantitative data can be extracted and synthesized and data sets can be treated according to different research questions analyzing for example uses in specific areas, of different ethnic groups or user groups, which is essential for practical applications on a local level. In this article we give an overview on the technical structure and the content of the database and discuss at the end the possible output for practical application. The database was set up in the frame of the EU-funded Project UNDESERT.
The Biodiversity of African Plants, 1996
L’etude est realisee dans le Parc national du W du Niger situe au sud-ouest du pays. L’objectif p... more L’etude est realisee dans le Parc national du W du Niger situe au sud-ouest du pays. L’objectif principal est de faire un etat des lieux de differents types de vegetation et de les decrire. La methode classique de numerisation sur ecran sur la base des images satellites Landsat ETM+ 2005 est utilisee. La classification effectuee a ete validee sur la base des releves phytoecologiques du terrain. Ainsi, la typologie realisee a permis de definir 19 classes d’occupation des terres. Les formations vegetales les mieux representees sont les savanes, les brousses tachetees et la vegetation clairsemee sur affleurement rocheux avec respectivement 41, 19 et 16 %. La carte de vegetation issue de cette etude pourra servir de support aux actions d’amenagement de cette aire protegee. Elle sera aussi une situation de reference pour l’analyse de la dynamique des ecosystemes de la zone.
Global Ecology and Biogeography, 2020
This is an open access article under the terms of the Creat ive Commo ns Attri bution License, wh... more This is an open access article under the terms of the Creat ive Commo ns Attri bution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
International Journal of Biological and Chemical Sciences, 2020
Cowpea is an important source of food and income for the populations of sub-Saharan Africa in gen... more Cowpea is an important source of food and income for the populations of sub-Saharan Africa in general and particularly in West Africa. However, farmers face storage and conservation problems. During storage in granaries, cowpea seeds are attacked by insects causing decreased grain weight and quality and sometimes a loss of germination capacity. Traditionally, farmers have used aromatic plants to limit insect damage. The aim of the present study is to test the insecticidal potential of three aromatic plants (Ocimum americanum L., Cymbopogon schoenanthus L. and Hyptis suaveolens Poit.). Cowpea seeds were mixed with increasing amounts of powder from each of the three plants and stored in plastic boxes for 10 month. The results showed that the number of defective seeds varied according to the treatment. O. americanum was the most efficient; the smallest effective dose of powder was 12%. For C. schoenanthus and H. suaveolens, the smallest effective doses were 16% and 18% respectively. Wi...
Journal of Agriculture and Environmental Sciences, 2017
International Journal of Environmental Health Research, 2020
The purpose of this paper is twofold: to explore the factors influencing the emergence and growth... more The purpose of this paper is twofold: to explore the factors influencing the emergence and growth of informal e-waste activities and to examine workers' motivation for involvement in informal e-waste activities. Semi-structured interviews and observations among actors in the recently established Dagomba-Line e-waste site in Kumasi, Ghana were employed to gather relevant data. Emergence and growth of e-waste activities are largely influenced by spatial, political, socio-cultural and economic factors. The reuse and open disposal of e-waste are the common practices due to the cost of transportation to a final disposal site. Similar to findings at the well-established Agbogbloshie e-waste site, also in Ghana, scavengers are found at the bottom of the e-waste financial ladder. The major motivating factor for engaging in e-waste handling is poverty. Additionally, some respondents mentioned the lucrative nature of the activity, landlessness, and peer influence as a motivation. The results showed that younger workers (below 35 years) were more likely to be engaged in the activity for reasons of peer influence and poverty and major source of livelihood . The paper recommends that policy and planning should reflect ways of delivering and creating stable socio-economic conditions that promote an inclusive and sustainable development.
Journal of Arid Environments, 2020
Abstract Reliable estimates of carbon stocks for drylands are constrained by a limited number of ... more Abstract Reliable estimates of carbon stocks for drylands are constrained by a limited number of biomass models for predicting accurately the biomass of dominant tree and shrub species. In this study, 119 trees with a diameter at breast height (dbh) between 3.82 and 45.48 cm were destructively sampled to evaluate aboveground biomass (AGB) allocation and prediction for four dryland species (Senegalia dudgeonii, Senegalia gourmaensis, Vachellia nilotica and Vachellia tortilis) commonly found in the Sudanian and Sahelian zones of Burkina Faso. Biomass allocation to leaf, branch and stem was examined using a classmometric analysis. Allometric equations relating biomass to dbh alone, and to dbh in combination with height and/or crown area were developed with and without consideration of the additivity property. Branches stored the largest (up to 90%) proportion of AGB. For three of the species, the branch mass fraction increased with increasing tree size at the expense of stem and leaf mass fractions. The statistical evaluations of the selected additive and non-additive models were satisfactory with no severe deficiencies. Diagnostics of model performance revealed that non-additive models performed better than additive models. The biomass models developed can be used for improved quantification of carbon stock and dynamics in dry savanna ecosystems.
BOIS & FORETS DES TROPIQUES, 2015
Les plantes oléagineuses locales offrent des usages multiples et constituent une source de revenu... more Les plantes oléagineuses locales offrent des usages multiples et constituent une source de revenus pour les communau- tés rurales. L’objectif de notre étude est de comprendre les perceptions et les savoirs des populations de la province du Kénédougou (Burkina Faso) concer- nant ces plantes et leurs huiles. La mé- thodologie utilisée est une combinaison de l’approche participative sociale et d’enquêtes ethnobotaniques. Au total,336 personnes ont été interrogées au sein de quatre groupes communautaires (Toussian, Siamou, Bolon et Peulh) à tra- vers 14 villages. Les résultats révèlent 11 plantes oléagineuses connues, parmi lesquelles quatre représentent 94 % de l’ensemble des citations. Le savoir sur les espèces ne varie significativement que selon l’âge (Χ2 = 8,11 ; p = 0,0173). Ce sont les adultes et les aînés qui dis- posent plus de savoir sur ces espèces. Les femmes sont les principales déten- trices des savoirs sur les techniques d’ex- traction des huiles et leur transformat...
Heliyon, 2019
Native tree foods contribute to food and nutrition security, health and income generation in sub-... more Native tree foods contribute to food and nutrition security, health and income generation in sub-Saharan Africa. However, the specific contribution of native tree foods to nutrition is poorly documented in science and often not acknowledged in poverty reduction strategies. This review gives an overview on the content of carbohydrates, proteins, fat, fibers, ash and dry matter of 98 native food tree species from sub-Saharan Africa. Data were grouped according to the food providing organ (seeds, fruits and leaves). In general, seeds had high content of fat, protein and dry matter; while leaves had high content of protein and ash. There was no significant difference between the three organs on the content of fibers and carbohydrate. Some tree foods species were good sources to provide carbohydrates, proteins, fat, fibers, ash and dry matter.
International Journal of Biological and Chemical Sciences, 2019
Arlomom - local trees for a better world video in french with english subtitles
Acknowledgements We wish to thank all SUN and BIOTA project members participating in the West Afr... more Acknowledgements We wish to thank all SUN and BIOTA project members participating in the West African Vegetation Data Network workshops held at the Research Institute Senckenberg in Frankfurt in December 2007 and at the Université de Oua-gadougou in November 2008. The SUN project is funded by the Commission of the European Community (INCO-031685).
Methods 155 structured household surveys to record: • Most valued wild food species • Collection/... more Methods 155 structured household surveys to record: • Most valued wild food species • Collection/consumption of wild food species, household characteristics and income • Change of wild food species (0 = no decline,-1 = decline,-2 = strong decline) • Substitutes for the top 10 cited wild food species when seasonally/ temporary unavailable
The evidence of increasing levels of greenhouse gases in the atmosphere is well accepted in the s... more The evidence of increasing levels of greenhouse gases in the atmosphere is well accepted in the scientific community. Changes in climate are one of the major implications that are currently being documented by various scientists around the globe. Some of the possible implications of climate change are changes in plant distribution, adaptations of the activities of man and plant evolution. If these implications are starting to take effect, then they will be affecting the plant phenology in an area. Vegetation phenology can change in five quite distinct ways;-1 A shift in the time of the peak of the season (Shift), 2 A broadening of the peak as can occur with global warming in areas where vegetation growth is temperature constrained (Broad), 3 An increase in the peak growth (Gain), and 4 A general increase throughout the year (Trend). 5 The emergence of multiple peaks A tool has been developed to derive five phenological change indices from a temporal NDVI or similar dataset, where these indices mimic the first four factors listed above and indicate when the fifth may be taking place. This paper summarises the development of these indices, discusses some of the more obvious findings from the Fasir dataset of the Sahelian region, used to derive the indices for the period 1982 – 1999, and discusses work done to try and validate these indices in the Sahelian region of Africa.