Forestry Research Center

Addis Ababa, Ethiopia

Forestry Research Center

Addis Ababa, Ethiopia
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Bussotti F.,University of Florence | Pollastrini M.,University of Florence | Pollastrini M.,Forestry Research Center
Forests | Year: 2017

The concern for the fate of forest ecosystems under climate change demands the development of a prompt and effective system for detecting the impacts of pressure factors, such as rising temperatures, drought conditions, and extreme climatic events. In ongoing European monitoring programs, the health condition of trees is only assessed visually as a matter of course and there is limited evidence that enhanced crown defoliation implies physiological disturbance and reduced tree growth. The progress of the research makes it possible to apply methods developed in experimental conditions in forests for the fast and reliable assessment of impacts and of stress conditions. In this review, we analyze the most promising indicators of tree and forest health (at individual plant and ecosystem levels) for their potential application in forest ecosystems and their ability to support and integrate the traditional visual assessment, provide information on influential factors, and improve the prediction of stand dynamics and forest productivity. © 2017 by the authors.

Ducci F.,Forestry Research Center
Annals of Silvicultural Research | Year: 2015

The purpose of this review is to examine a few aspects of global change effects on forest genetic resources and their interaction. Genetic resources can provide many opportunities for the development of adaptive forest management in the Mediterranean region. At the same time, forestry and its various disciplines can offer manifold chances to develop methods and techniques for the in situ and ex situ protection, as well as for the correct management of species and populations at risk because of climate change. Among these aspects, the studies on the Marker Assisted Selection are particularly taken into consideration, as well as the phenotypic plasticity and the different types of assisted migration. A special emphasis is given to genetic resources growing at marginal peripheral populations, which need to be safeguarded as possible containers of adaptive diversity. They are subjected, in fact, to an extreme climatic stress more than others.

Dejene T.,Forestry Research Center | Lemenih M.,International Water Management Institute IWMI | Lemenih M.,Wageningen University | Bongers F.,Wageningen University
Journal of Arid Environments | Year: 2013

African dry forests provide non-timber forest products (NTFPs) of high commercial value, such as frankincense and gum arabic. Nonetheless, their deforestation and conversion to croplands is intensifying. Expected higher financial return from crop production is a main driver of conversion, but research supporting this underlying claim is scarce. We compared the financial returns for two crop production options (sesame and cotton) and forest use, in a dry forest area known for its frankincense production in northern Ethiopia. Net revenue was highest for sesame and lowest for cotton agricultural use. The forest based revenue was intermediate. The revenues from the crop production options were more sensitive to a range of uncertainties than the forest land use. Our results show that forest land use that includes commercial NTFPs is financially competitive to some commercial crop options and offers returns of better reliability. The hypothesis that forest based revenues are lower than crop based ones is not supported by our results. Therefore, the continued deforestation of dry forests cannot be explained by lower returns alone, but other factors such as awareness, market access, property right and institutional issues may also play a role to drive deforestation and conversion of dry forests to croplands. © 2012 Elsevier Ltd.

Cantiani P.,Forestry Research Center | Chiavetta U.,Forestry Research Center
IForest | Year: 2015

Black pine has been used often in central and southern Italy to reforest mountainous areas depleted by the intensive use of natural resources. The main purpose of establishing pine forests in Italy was to protect the soil from excessive erosion, and also to facilitate the natural succession toward mixed forests with deciduous species. The most common silvicultural treatments in Europe currently aim at maximizing the stability of the stands and facilitating the transition from pure to mixed stands comprising a larger component of native tree species. In this work, we investigated the relationships between the living whorls number and four indexes of individual tree stability: the slenderness ratio, the crown depth, the crown projection, and an eccentricity index of the canopy. The data set used was composed of 1098 trees from ten black pine plantations located in central Italy. Our results demonstrate that the living whorls number can be handily used to predict the slenderness ratio with an error of 18%. A non-parametric model based on a reduced number of field measures was obtained as a support for thinning operations aimed at improving single tree stability. © SISEF.

Corona P.,Forestry Research Center
Environmental Research | Year: 2016

Forests provide a wide range of ecosystem services from which people benefit, and upon which all life depends. However, any rational decision related to the maintenance and enhancement of the multiple functions provided by the forests needs to be based on objective, reliable information. As such, forest monitoring and assessment are rapidly evolving as new information needs arise or new techniques and tools become available. Global change issues and utilities from ecosystem management are distinctively to be considered, so that forest inventory and mapping are broadening their scope towards multipurpose resources surveys. Recent changes in forest management perspective have promoted the consideration of forests as complex adaptive systems, thereby highlighting the need to account that such approaches actually work: forest monitoring and assessment are then expected to address and fully incorporate this perspective at global scale, seeking to support planning and management decisions that are evidence-based. This contribution provides selected considerations on the above mentioned issues, in the form of a commented discussion with examples from the literature produced in the last decade. © 2015 Elsevier Inc.

Manetti M.C.,Forestry Research Center | Becagli C.,Forestry Research Center | Sansone D.,Forestry Research Center | Pelleri F.,Forestry Research Center
IForest | Year: 2016

Tree-oriented silviculture is an innovative approach of forest management aimed at enhancing a limited number of early-selected crop trees whose growth is favored over the full rotation period by applying frequent thinning in their neighborhood. This approach was originally applied to high forests, but can also be applied to coppices to maintain or improve biodiversity by selecting valuable timber trees and/or minority species as target trees. The main limitation of this silvicultural option is the need of specialized and qualified operators in all the phases, from selection of crop trees to logging operations. In this study, experimental trials were established by the Forest Research Centre of Arezzo (Italy) to verify the suitability of this approach to different structural and enviromental conditions. In coppices characterized by fast growing species such as chestnut, tree-oriented silviculture has been applied to a limited number of crop trees (50-100 ha) to obtain more valuable and largersized assortments in a shorter rotation period, reducing at the same time the silvicultural costs. In mixed coppices, where the ordinary management (coppicing) was applied, the abandonment or the conversion into high forest gave rise to a progressive loss in terms of species composition. Contrastingly, thinning focused around a few (5-20) trees of sporadic species allowed to maintain a high level of biodiversity, and led to favorable conditions for growth and regeneration of these species. © SISEF.

Deforestation has caused surface and underground water imbalance in the hydrologic cycle followed by subsequent food, feed and wood productivity crisis. This paper reviews the role of traditional farming systems in wet and dry agroecology. It further compares it with existing improper farming practice, which productivity is examined from agroecology based climatic and edaphic perspective. Experiments were carried out to determine the amount of rainfall intercepted by dominant trees on farm, namely by Cordia africana, Afrocarpus falcatus, Millettia ferruginea, Juniperus procera, Syzy-gium guineense, Olea europaea subsp. cuspidata, Acacia albida, Albizia gummifera and Moringa stenopetala. Deep rooted trees planted on farms are found to be sources of feed, food and moisture conservers, that sustain and boost production in moisture scarce agriculture. Under irrigation they are found to be good for salinity protection and marginal land reclamation. Soil infiltration data from secondary sources were examined for cultivated area, wood land and open overgrazed pasture in central Rift Valley. The relative infiltration rates are highest for grasslands. This research work is intended to initiate interdisciplinary networking approach in water and natural resource conservation, proper land use potential development and environmental sustainability.

Yirgu A.,Forestry Research Center | Tsega M.,Ethiopian Institute of Agricultural Research
Agroforestry Systems | Year: 2015

Faidherbia albida is an indigenous tree species in Ethiopia and utilized by farmers in various ways. It is an ideal agroforestry tree in several tropical countries. Pre-dispersal seed predation of F. albida was investigated in the central Rift Valley of Ethiopia, Awassa. The objective of the study was to identify seed predators associated with F. albida and determine the level of damage exerted on seed germination. Matured pods of non-burst seeds were collected and used for collecting seed predators. Furthermore, seeds from these pods were collected, categorized into infested and non-infested seeds, and allowed to germinate under different treatments. Both Bruchidius cadei n.sp. and Bruchidius auratopubens n.sp. emerged from seeds of F. albida. These bruchids infested about 27 % of seeds. Predation and subsequent fungal infestation had reduced the seed viability and performance of seed germination among infested seeds. Therefore, these predators have practical implications because of their negative contribution to the regeneration of F. albida trees across growing regions. © 2015, Springer Science+Business Media Dordrecht.

Fattorini L.,University of Siena | Corona P.,Forestry Research Center | Chirici G.,University of Florence | Pagliarella M.C.,University of Siena
Environmetrics | Year: 2015

The purpose of this paper is to compare some spatial strategies for sampling polygons onto a grid partitioning a study area. Most of the schemes considered in the paper are aimed at avoiding the selection of neighboring polygons. When one or more auxiliary variables are similar or well correlated with the values of the survey variable, the auxiliary information is adopted at estimation level by means of the difference or the regression estimators, or at design level, using the values of auxiliary variables to determine the inclusion probabilities. Applications to large-scale forest inventories, land use estimation, and forest cover estimation are discussed. A simulation study is performed to compare the adopted strategies in terms of bias (if present), accuracy, and accuracy estimation. The simulation is designed to mimic forest inventories and forest cover estimation, starting from some real situations. An application to plan future surveys for land use estimation in Italy is reported. © 2015 John Wiley & Sons, Ltd.

An effective fertilizer system is required to achieve high and stable grain protein levels in the wheat cultivar “ChikushiW2” for Chinese noodles. In this study, we examined the fertilizer nitrogen utilization rate (FNU), grain nitrogen content, nitrogen contribution ratio (NCR) of nitrogen fertilizer, and nitrogen fertility using 15N-labeled ammonium sulfate in “ChikushiW2” to determine the nitrogen kinetics in wheat plants. At the early-ripening stage, nitrogen was distributed within the range 78-83% in foliage and 17-22% in grain. Nitrogen translocated from foliage to grain during the middle-ripening stage, with a final grain accumulation of 87-89% of the nitrogen at the late-ripening stage. FNU of the basal dressing was the lowest at 15-20%, increasing to 37-56% for the topdressing at tillering stage with annual variation, and highest at 67-74% for the topdressing at the panicle formation stage and the topdressing at full heading. NCR in the grain nitrogen content was lowest at 4-7% for basal dressing, 10-14% for the topdressing at the tillering stage and topdressing at the panicle formation stage, 24-30% for the topdressing at full heading, and highest at 41-49% for nitrogen fertility. These results indicate that reducing the quantity of low FNU basal dressing, reducing the variable FNU on the topdressing at the tillering stage, and adjusting the timing and quantity of fertilizer application on the high-FNU topdressing at the panicle formation stage, may be effective in enhancing and stabilizing the grain protein content. © 2016, Crop Science Society of Japan. All rights reserved.

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