Jean M Stephan
Lebanese University, Life sciences and earth, Faculty Member
Research Interests:
Research Interests:
Research Interests:
PurposeLebanon has been subject to important reforestation activities which resulted in the establishment of several cedars, pine and other mixed forest stands on communal lands. These stands are not designated for timber production but... more
PurposeLebanon has been subject to important reforestation activities which resulted in the establishment of several cedars, pine and other mixed forest stands on communal lands. These stands are not designated for timber production but rather for nonwood forest products (NWFPs), landscape restoration and for environmental services. The study aims at valuating old reforested sites from the perspective of rural communities neighboring those reforested stands.Design/methodology/approachTo assess the non-timber goods and services provided by these forest ecosystems, 13 reforested sites located in different regions in Lebanon were selected. The socioeconomic assessment was done using questionnaires distributed to locals that have close interactions with the neighboring forests; it included, among others, a double-bonded dichotomous contingent valuation (CV) related to their willingness to pay (WTP) for reforestation and forest management activities.FindingsResults of the goods and servi...
Research Interests:
Research Interests:
The Syrian juniper, Juniperus drupacea Labill has a very limited distribution and is facing severe fragmentation and dieback in Lebanon. The present investigation is a pilot study conducted in Jabal Moussa Biosphere Reserve in order to... more
The Syrian juniper, Juniperus drupacea Labill has a very limited distribution and is facing severe fragmentation and dieback in Lebanon. The present investigation is a pilot study conducted in Jabal Moussa Biosphere Reserve in order to develop a plan for conservation and sustainable management of this species. A total of 106 individuals were studied from five areas. The correlations between environmental factors (altitude, exposition, and slope) as well as canopy density with the trees distribution, size and vitality were investigated. The most remarkable individuals were mainly found in Aarbi, the central karstic area in association with Quercus calliprinos Webb., Q. infectoria Oliv. and Pistacia palaestina Boiss. The statistical analysis showed that the optimum conditions for Juniperus drupacea growth is at middle altitudes, at western expositions with low slope and in relatively open forest. In short term, to manage and conserve this unique species, we can perform a selective cut...
The 13-page "First molecular-based contribution to the checklist of Lebanon macrofungi" by Sleiman, Bellanger, Richard, and Stephan may now be downloaded from Mycotaxon's mycobiota webpage. This well-documented annotated... more
The 13-page "First molecular-based contribution to the checklist of Lebanon macrofungi" by Sleiman, Bellanger, Richard, and Stephan may now be downloaded from Mycotaxon's mycobiota webpage. This well-documented annotated species list brings to 148 the number of free-access fungae now available on our website: http://www.mycotaxon.com/mycobiota/index.html
Research Interests:
Research Interests:
The taxonomy of oaks in Lebanon relies on the works of Mouterde (1966). Since half a centrury, there were no taxonomic revision for these species, namely for Quercus pinnatifida Gmelin, which is no more in use worldwide after successive... more
The taxonomy of oaks in Lebanon relies on the works of Mouterde (1966). Since half a centrury, there were no taxonomic revision for these species, namely for Quercus pinnatifida Gmelin, which is no more in use worldwide after successive nomenclature revisions. This name was replaced by Quercus pubescens Willd. subsp. pubescens which has never been recorded in Lebanon. However, Quercus kotschyana O. Schwarz is cited as an endemic species of Lebanon, but it was never mentioned by Mouterde works, nor by the literature that followed (i.e. Abi Saleh, 1976, 1996; Menitsky, 2005; Tohme & Tohme, 2014). This work aims at revealing the taxonomy of an endemic oak of Lebanon, and clarify the existing confusion in the nomenclature of species. The comparison of collected plant material from different sites, with the holotype of Quercus kotschyana, and the botanical description and drawings found in the literature, allowed us to conclude that Quercus pinnatifida Gmel. was wrongly attributed to the...
Research Interests:
This study contributes in listing and understanding the distribution of riparian species according to environmental and anthropogenic factors, recognizing the impact of these factors on biodiversity and tree growth and conducting an easy... more
This study contributes in listing and understanding the distribution of riparian species according to environmental and anthropogenic factors, recognizing the impact of these factors on biodiversity and tree growth and conducting an easy method for the assessment of habitat quality in a typical riparian ecosystem in the Eastern Mediterranean Basin. The methodology involved field assessment and the evaluation of riparian habitat quality by giving scores to different criteria, composing the habitat quality index. The results showed that river channel deviation is the most significant factor affecting riparian habitat quality. Non disturbed sites have significant higher scores, yet they are not classified as in natural conditions due to the effect of intrinsic environmental factors on habitat quality, namely bioclimatic conditions and river flow regime. An increase of biodiversity was recorded when habitat quality improved. Higher riparian habitat quality resulted in the presence of ol...
Research Interests:
Research Interests:
This phytosociological study of the Dreib Region in Akkar-Lebanonis the first on basaltic bedrockin Lebanon. Thesynusial methods isused and compared bynumerical classification. The latter shows satisfactory results when compared to the... more
This phytosociological study of the Dreib Region in Akkar-Lebanonis the first on basaltic bedrockin Lebanon. Thesynusial methods isused and compared bynumerical classification. The latter shows satisfactory results when compared to the synusial manual classification. The followingplant associations are defined:Quercetum veneris–ithaburensis, Calicotomo villosae –Rhamnetum punctati, Eryngio cretici –Echietum angustifolii and Sileno aegyptiacae –Isatidetum lusitanicae.Consequently, the alliance Quercion ithaburensi is stated for the first time in Lebanon. Vegetationseries for progressive and regressive successions are also produced. Further relevés are required to consolidate additional associations that are depicted from both synusial and numerical vegetation classifications.
Research Interests:
Research Interests:
Page 1. Ramzi Touchan Æ Elena Xoplaki Æ Gary Funkhouser Ju¨rg Luterbacher Æ Malcolm K. Hughes Æ Nesat Erkan U¨nal Akkemik Æ Jean Stephan ... Most studies are recent (Akkemik 2000; Akkemik and Aras 2005; Akkemik et al. ...
Research Interests: Engineering, Environmental Science, Oceanography, Technology, Principal Component Analysis, and 15 moreSea Level, Time series analysis, Biological Sciences, Climate Dynamics, Atmospheric sciences, Dendroclimatology, Extreme Value Theory, Atmospheric Circulation, Eastern Mediterranean, Tree Ring, Large Scale, Summer, Pressure Gradient, Atmospheric Temperature, and surface air temperature
Research Interests:
Few studies addressed the distribution of riparian trees and shrubs, and the factors affecting their distribution and structure in Lebanon. The objective of this investigation is to identify the riparian tree and shrub species around Nahr... more
Few studies addressed the distribution of riparian trees and shrubs, and the factors affecting their distribution and structure in Lebanon. The objective of this investigation is to identify the riparian tree and shrub species around Nahr Ibrahim River. We selected 21 sites covering all altitudinal range from sea level up to 1766 m as well as a cross section gradient from river bed. Results showed that biodiversity indices are affected by bioclimatic conditions (vegetation stages) and river flow regime. A moderate dry period of less than 3 months seems to have a positive effect on species richness and composition (trees vs shrubs). A regulated flow would increase the number of tree individuals and reduce biodiversity. Salix acmophylla Boiss., Salix alba L. and Platanus orientalis L. are obligate riparian (phreatophytes) and Salix libani Bornm., Ostrya carpinifolia Scop., Juglans regia L., Crataegus monogyna Jacq. are classified as facultative riparian (facultative phreatophytes). Fu...
Research Interests:
Research Interests:
Research Interests: Plant Biology and Flora
Mediterranean forests are unique and one of the most threatened biomes worldwide (Klausmeyer and Shaw 2009). They are distributed through marked ecological gradients that are supported by a wide variety of diverse geology and contrasting... more
Mediterranean forests are unique and one of the most threatened biomes worldwide (Klausmeyer and Shaw 2009). They are distributed through marked ecological gradients that are supported by a wide variety of diverse geology and contrasting bioclimatic conditions. Marcescence (i.e., the abscence of leaf fall abscission; Addicott 1982), is a life-history trait related to contrasting or transitional climatic areas such as those across Eurosiberian and Mediterranean Regions (García-Mijangos et al. 2014). Thus, marcescent forests are ecotones located in the transition between temperate areas with cold winters and mild rainy summers and mediterranean regions with dry and hot summers (Rivas-Martínez et al. 2017). We aim to provide a global overview of marcescent forests in the Mediterranean basin, a significant ecotone in terms of biogeography and conservation, by exploring the main ecological drivers that have promoted past, current and future changes in the distribution ranges of several o...
The first large-scale network of 79 tree-ring chronologies in the Eastern Mediterranean and Near East (EMNE; 33°N–42°N, 21°E–43°E) is described and analyzed to identify the seasonal climatic signal in indices of annual ring width.... more
The first large-scale network of 79 tree-ring chronologies in the Eastern Mediterranean and Near East (EMNE; 33°N–42°N, 21°E–43°E) is described and analyzed to identify the seasonal climatic signal in indices of annual ring width. Correlation analysis and cluster analysis are applied to tree-ring data and gridded climate data to assess the climate signal embedded in the network in preparation for climate field reconstructions and formal proxy/model intercomparison experiments. The lengths of the 79 combined chronologies range from 89 to 990 years. The monthly correlations and partial correlations reveal a pervasive positive association with May, June, and sometimes July precipitation, positive correlations with winter and spring (December through April) temperatures, and negative relationships with May through July temperature, although as expected, there are site-to-site exceptions to these general patterns. Cluster analysis suggests three groups of sites based on their association...
Research Interests:
Research Interests:
This phytosociological study of the Dreib Region in Akkar-Lebanon is the first on basaltic bedrock in Lebanon. The synusial methods is used and compared by numerical classification. The latter shows satisfactory results when compared to... more
This phytosociological study of the Dreib Region in Akkar-Lebanon is the first on basaltic bedrock in Lebanon. The synusial methods is used and compared by numerical classification. The latter shows satisfactory results when compared to the synusial manual classification. The following plant associations are defined: Quercetum veneris-ithaburensis, Calicotomo villosae-Rhamnetum punctati, Eryngio cretici-Echietum angustifolii and Sileno aegyptiacae-Isatidetum lusitanicae. Consequently, the alliance Quercion ithaburensi is stated for the first time in Lebanon. Vegetation series for progressive and regressive successions are also produced. Further relevés are required to consolidate additional associations that are depicted from both synusial and numerical vegetation classifications.
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Research Interests:
Increasing attention is being given to climate technologies on the international climate change agenda, not least in the agricultural sector and water sectors, and to technologies for adaptation. However investments in technology-based... more
Increasing attention is being given to climate technologies on the international climate change agenda, not least in the agricultural sector and water sectors, and to technologies for adaptation. However investments in technology-based adaptation (seeds, dams, irrigation, etc.) are complicated by the fact that it remains difficult to predict future climate change impacts, especially on a local scale. In addition, evidence for the costs and benefits of implementing adaptation technologies is relatively limited. The analysis presented in this paper shows that there is a large potential for integrating adaptation technologies into the planning and implementation of ongoing and future projects. Based on local-level data from a technology needs assessment project in Lebanon, this paper presents two examples of the economic feasibility of implementing adaptation technologies in the agricultural and water sectors. The results show that the technologies can be applied at low cost and with relatively little effort.
Research Interests:
This study represents the first large-scale systematic dendroclimatic sampling focused on developing chronologies from different species in the eastern Med-iterranean region. Six reconstructions were developed from chronologies ranging in... more
This study represents the first large-scale systematic dendroclimatic sampling focused on developing chronologies from different species in the eastern Med-iterranean region. Six reconstructions were developed from chronologies ranging in length from 115 years to 600 years. The first reconstruction (1885–2000) was derived from principal components (PCs) of 36 combined