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Improving the Livelihood of the Rural Population through the Production of Bushmeat in Ghana

Background: Ghanas transition forests, neighbouring savannahs and timber plantations in the Ashanti region face a constant degradation due to the increased occurrence of fires. In most cases the fires are deliberately set by rural people for hunting purposes. Main target is a cane rat, here called grasscutter (Thryonomys swinderianus), whose bushmeat is highly esteemed throughout the country. The animal is a wild herbivorous rodent of subhumid areas in Africa south of the Sahara. The grasscutter meat is an important source of animal protein. Existing high-value timber plantations (mainly Teak, Tectona grandis) are affected by fires for hunting purposes. Thus resulting in growth reduction, loss of biomass or even complete destruction of the forest stands. It became obvious that solutions had to be sought for the reduction of the fire risk. Objectives: Since 2004 the Institute for World Forestry of the Federal Research Centre for Forestry and Forest Products, Hamburg, Germany is cooperating with a Ghanaian timber plantation company (DuPaul Wood Treatment Ltd.) the German Foundation for Forest Conservation in Africa (Stiftung Walderhaltung in Afrika) and the Center for International Migration with the purpose to improve the livelihood of the rural population in the surroundings of the forest plantation sites and simultaneously to safeguard and improve the timber plantations. The introduction of grasscutter rearing systems to local farmers accompanied by permanent agricultural and agroforestry practices appeared to be a promising approach for the prevention of fires in the susceptible areas. Additionally a functioning grasscutter breeding system could contribute to the improvement of food security, development of income sources and the alleviation of poverty. The following measures are implemented: - Identification of farmers interested in grasscutter captive breeding, - Implementation of training courses for farmers on grasscutter rearing, - Delivery of breeding animals, - Supervision of rearing conditions by project staff, - Development of a local extension service for monitoring activities, - Evaluation of structures for grasscutter meat marketing. Results: After identification of key persons for animal rearing training courses were successfully passed and animals were delivered subsequently. Further investigations will evaluate the effects of the grasscutter rearing in the project region. This will be assessed through the - Acceptance of grasscutter rearing by farmers, - Success of the animal caging, - Reproduction rate, - Meat quality, - Marketing success of meat, - Reduction of fire in the vicinity of the timber plantations, - Improvement of peoples livelihood.

14C content of specific organic compounds in subsoils

Organic matter (OM) composition and dynamic in subsoils is thought to be significantly different from those in surface soils. This has been suggested by increasing apparent 14C ages of bulk soil OM with depth suggesting that the amount of fresh, more easily degradable components is declining. Compositional changes have been inferred from declining ä13C values and C/N ratios indicative for stronger OM transformation. Beside these bulk OM data more specific results on OM composition and preservation mechanisms are very limited but modelling studies and results from incubation experiments suggest the presence and mineralization of younger, 'reactive carbon pool in subsoils. Less refractory OM components may be protected against degradation by interaction with soil mineral particles and within aggregates as suggested by the very limited number of more specific OM analysis e.g., identification of organic compound in soil fractions. The objective of this project is to characterize the composition, transformation, stabilization and bioavailability of OM in subsurface horizons on the molecular level: 1) major sources and compositional changes with depth will be identified by analysis of different lipid compound classes in surface and subsoil horizons, 2) the origin and stabilization of 'reactive OM will be revealed by lipid distributions and 14C values of soil fractions and of selected plant-specific lipids, and 3) organic substrates metabolized by microbial communities in subsoils are identified by distributional and 14C analysis of microbial membrane lipids. Besides detailed analyses of three soil profiles at the subsoil observatory site (Grinderwald), information on regional variability will be gained from analyses of soil profiles at sites with different parent material.

Schwerpunktprogramm (SPP) 1685: Ecosystem nutrition: forest strategies for limited phosphorus resources; Ökosystemernährung: Forststrategien zum Umgang mit limitierten Phosphor-Ressourcen, Phosphorus transport along soil pathways in forested catchments

Phosphorus (P) is an essential nutrient for living organisms. Whereas agriculture avoids P-limitation of primary production through continuous application of P fertilizers, forest ecosystems have developed highly efficient strategies to adapt to low P supply. A main hypothesis of the SPP 1685 is that P depletion of soils drives forest ecosystems from P acquiring system (efficient mobilization of P from the mineral phase) to P recycling systems (highly efficient cycling of P). Regarding P fluxes in soils and from soil to streamwater, this leads to the assumption that recycling systems may have developed strategies to minimize P losses. Further, not only the quantity but also the chemistry (P forms) of transported or accumulated P will differ between the ecosystems. In our project, we will therefore experimentally test the relevance of the two contrasting hypothetical nutritional strategies for P transport processes through the soil and into streamwater. As transport processes will occur especially during heavy rainfall events, when preferential flow pathways (PFPs) are connected, we will focus on identifying those subsurface transport paths. The chemical P fractionation in PFPs will be analyzed to draw conclusions on P accumulation and transport mechanism in soils differing in their availability of mineral bound P (SPP core sites). The second approach is an intensive streamwater monitoring to detect P losses from soil to water. The understanding of P transport processes and P fluxes at small catchment scale is fundamental for estimating the P exports of forest soils into streams. With a hydrological model we will simulate soil water fluxes and estimate P export fluxes for the different ecosystems based on these simulations.

Konzeption zur Erhaltung und Wiederherstellung lichter Wälder in Baden-Württemberg

Lichte Wälder kommen natürlicherweise dort vor, wo die Standortsbedingungen für das Baumwachstum extrem sind, z.B. in bodentrockenen Karstlandschaften. Zudem sind lichte Waldstrukturen anzutreffen, die aus menschlicher Waldbewirtschaftung hervorgegangen sind, wie etwa Hutewälder. Lichten Wäldern wird ein besonders hoher naturschutzfachlicher Wert zugesprochen. Diese besondere Wertigkeit liegt in der Struktur- und Habitatvielfalt, der Standortsdynamik und der oftmals langen Biotoptradition begründet. Lichte Wälder sind heute in der Landschaft meist nur noch kleinräumig und isoliert oder in Form gepflegter Restbestände zu finden. Öfter sind unbewirtschaftete, in Sukzession befindliche Relikte auszumachen, die sich dynamisch in Richtung der Schlusswaldgesellschaften entwickeln und ihre besonderen Lebensraumeigenschaften zunehmend verlieren. Zum Erhalt dieser wertvollen Lebensräume werden in natürlich lichten Wäldern Pflege- und Entwicklungsmaßnahmen betrieben, Auflichtung und Biomasseaustrag sind dabei die wichtigsten Maßnahmen. In anthropogen lichten Wäldern bietet sich die Rückkehr zu den originären Bewirtschaftungsmaßnahmen unter Anpassung an moderne Anspruchslagen an. Dazu werden in Pilotprojekten in verschiedenen Naturräumen unterschiedliche Lichtwaldtypen freigestellt und Beweidungs- und Streuentnahmevorhaben eingerichtet. Diese Maßnahmen werden mittels eines Monitorings begleitet. Auch die wirtschaftliche Tragfähigkeit solcher Bewirtschaftungssysteme findet in dem Projekt Berücksichtigung. Neben einer teilweisen Refinanzierung der Maßnahme ist so zu erwarten, dass dadurch ein höherer Erfolg der Maßnahme erzielt werden kann. Der Erfolg der Maßnahmen soll über die Waldbiotopkartierung und Forsteinrichtung regelmäßig erhoben werden. Für den Staatswald Baden-Württembergs wird ein Lichtwaldkonzept verfasst, das die ökologisch wünschenswerte Weiterentwicklung der natürlichen und anthropogenen Lichtwälder beschreibt. Das Konzept wird in enger Abstimmung mit dem Konzept zu den Waldzielarten erstellt. Wichtige Aspekte sind dabei: a) Die Erhebung und Auswahl geeigneter Standorte für natürlich lichte Wälder sowie für Weide- und Hutewaldflächen (Kriterien: Strukturen, Artvorkommen, Größe, Biotopverbund, technische Voraussetzungen für eine erfolgreiche Bewirtschaftung). B) Die beispielhafte Umsetzung von Pflege- und Entwicklungsmaßnahmen auf konkreten Einzelflächen, unter Einbeziehung historischer Waldnebennutzungen (z. B. Waldweide), mit begleitendem Monitoring. C) Die Erstellung einer bedarfsgerechten Konzeption für Baden-Württemberg zur Umsetzung von Bewirtschaftungsmaßnahmen in Form von Freistellungsmaßnahmen, Weide- und Hutewaldprojekten. D) Schulungen für Praktiker.

Entwicklung eines EDV-unterstuetzten Entscheidungsinstruments zur Standortvorauswahl von Kernenergieanlagen

Auswahl von Standorten fuer Kernenergieanlagen und Einzelstandortbewertung unter besonderer Beruecksichtigung des nuklearspezifischen Risikos. Entwicklung eines bundeseinheitlichen EDV-unterstuetzten Verfahrens zur Beschleunigung des Genehmigungsverfahrens. Erfassung und nutzwertanalytische Verarbeitung von Standortdaten.

Mixed layer depth values for the n = 1968 modern dinocyst database extracted from the World Ocean Atlas 2018, Argo floats data 2005-2017

Monthly, seasonal and annual mixed layer depth (MLD) values at the 1968 sites of the modern dinocyst database by de Vernal et al. (2020). The MLD values were extracted from the World Ocean Atlas 2018 (WOA18) objectively analyzed mean field of Argo floats data of 2005-2017 using a density threshold of 0.125 kg/m3 with reference to 10 m depth. In order to get an MLD value that corresponds to each site, the MLD climatology products were interpolated to the previously published 1968 sites.

Mixed layer depth values for the n = 1968 modern dinocyst database extracted from the World Ocean Atlas 2018, climate normal 1981-2010

Monthly, seasonal and annual mixed layer depth (MLD) values at the 1968 sites of the modern dinocyst database by de Vernal et al. (2020). The MLD values were extracted from the World Ocean Atlas 2018 (WOA18) objectively analyzed mean field of the climate normal of 1981-2010 using a density threshold of 0.125 kg/m3 with reference to 10 m depth. In order to get an MLD value that corresponds to each site, the MLD climatology products were interpolated to the previously published 1968 sites.

Mixed layer depth values for the n = 1968 modern dinocyst database extracted from the monthly climatology by Holte et al. (2017)

Monthly, seasonal and annual mixed layer depth (MLD) values at the 1968 sites of the modern dinocyst database by de Vernal et al. (2020). The MLD values were extracted from the monthly climatology based on Argo profiles of 2000-2021 by Holte et al. (2017). MLD values corresponding to each of the the previously published 1968 sites were determined with a density algorithm.

Mixed layer depth values for the n = 1968 modern dinocyst database extracted from the monthly climatology by de Boyer Montégut (2023)

Monthly, seasonal and annual mixed layer depth (MLD) values at the 1968 sites of the modern dinocyst database by de Vernal et al. (2020). The MLD values were extracted from the monthly climatology based on profile data of 1970-2021 by de Boyer Montégut (2023) using a density threshold of 0.03 kg/m3 with reference to 10 m depth. In order to get an MLD value that corresponds to each site, the MLD climatology products were interpolated to the previously published 1968 sites.

Ready-to-use version of the Eurasian Modern Pollen Database version 2, with 90 pollen taxa and 7634 sites

Ready-to-use version of the Eurasian Modern Pollen Database version 2 (EMPD2; Davis et al., 2020; Chevalier et al., 2019) that includes 90 taxa and 7634 modern pollen samples with pollen sums (excluding Pinus) higher or equal to 100 pollen grains (Tables 1 to 6). Table 7 contains 394 additional sites with pollen sums less than 100 pollen grains when excluding Pinus but higher or equal to 100 pollen grains when Pinus is included. Users can merge Tables 1 and 7 (8028 modern pollen samples) if they consider pollen sums (including Pinus) equal or higher than 100 pollen grains sufficient for accurate reconstructions. This ready-to-use version of the EMPD2 was initially built to do paleoclimatic reconstructions for Southern Europe. For users willing to do paleoclimate reconstructions in regions that may need to re-include some of the taxa that were removed, the intermediate version containing all the counts for the 840 initial taxa and the first grouping to 192 taxa is also available as Table 8.

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