Nutritional diagnoses of oriental beech trees in damaged Caspian forest sites, using the diagnosis and recommendation integrated system (DRIS)

Oriental beech established in the Hyrcanian forests, is a valuable tree whose habitats are constantly exposed to destructive factors which change the nutritional status of soil and leaves. Analysis of foliar elements is a commonly used method for studying tree nutrient status that indicates site's quality. Foliar analysis of beech (Fagus orientalis Lipsky) was carried out in Kojour (Mazandaran) in order to assess the nutritional balance of trees in a damaged forest site (a direct result of livestock grazing and anthropogenic perturbations). Sunny leaves of dominant trees were taken in August and foliar concentration of macroelements, N, P, Ca, K and Mg were measured. The diagnosis and recommendation integrated system (DRIS) analysis was applied for evaluating the nutritional state. The results showed deficiency with K and P in disturbed stands. Nutrient Balance Index (NBI) indicated imbalance in nutrient status. These results suggest the usefulness of DRIS for foliar tissue analysis as an indicator of nutritional status and elemental stress in natural forests

Réponses morphologiques, physiologiques et biochimiques au déficit en eau chez les jeunes plants de trois populations de poiriers sauvages (Pyrus boisseriana)

Water shortage limits production of fruit orchards, like pear, in arid and semi-arid regions. The identification of wild pear germplasm for potential use as rootstock would be valuable for pear cultivation in semi-arid regions. Relative drought tolerance of wild pear germplasm (Pyrus boisseriana) from three different populations distributed along an elevational gradient (semi-arid 1000, semi-wet 1350 and semi-wet 1600 populations) was evaluated in a greenhouse trial. Established container-grown seedlings were exposed to 18 days of simulated drought, or not, followed by a seven day recovery. Biomass allocation and accumulation, physiological (stomatal conductance, photosynthesis, transpiration, xylem water potential) and biochemical parameters (leaf pigments, free proline, malondialdehyde and hydrogen peroxide production) were evaluated. Although all populations were able to recover from water shortage, thereby being relatively drought tolerant, some differences among populations were detected for gas exchange parameters, biomass accumulation and proline concentration in favor of the semi-arid 1000 elevation population, which was more drought tolerant; it had the most rapid and complete recovery of physiological activity (stomatal conductance and carbon fixation). In addition, all populations increased carotenoids in leaves. Overall, we showed that plants from semi-arid 1000 elevation greater tolerance to drought than those from higher elevations. Although the initial drought resistance response of the 1000 elevation source was promising, additional field studies are needed to confirm the greenhouse results and the benefit of a more drought resistant rootstock to commercial scions.En régions arides et semi-arides, la disponibilité en eau est le facteur limitant des vergers de production, comme en culture de poirier, par exemple. À cet égard, l’évaluation d’une collection de poiriers sauvages pourrait mettre en évidence du matériel potentiellement utilisable comme porte-greffe et tolérant à la sécheresse dans ces régions. Des poiriers sauvages (Pyrus boisseriana) originaires de trois populations différentes selon leur répartition en altitude (populations « semi-aride 1 000 m », « semi-humide 1350 m » et « semi-humide 1 600 m ») ont été évalués pour leur tolérance à la sécheresse dans un essai en serre. Des semis cultivés en pots ont été soumis à 18 jours de sécheresse, puis à une reprise de sept jours de croissance en conditions normales d’irrigation. La répartition et l’accumulation de la biomasse, les paramètres physiologiques (conductance stomatique, photosynthèse, transpiration, potentiel hydrique du xylème) et biochimiques (teneurs en pigments des feuilles, proline libre et malondialdéhyde ; production de peroxyde d’hydrogène) ont été évalués par rapport à des témoins non soumis au stress hydrique. Bien que toutes les populations de poirier aient pu se rétablir après la période sans irrigation et présentent de ce fait une certaine tolérance à la sécheresse, certaines différences de comportement entre celles-ci ont été détectées pour ce qui concerne les échanges gazeux, l’accumulation de la biomasse et la concentration de la proline dont les valeurs étaient en faveur de la population établie en zone semi-aride à une altitude de 1000 m. Celle-ci a d’ailleurs montré une reprise plus rapide et plus complète de son activité physiologique (conductance stomatique et fixation du carbone). À noter que le taux de caroténoïdes dans les feuilles a augmenté dans toutes les populations soumises au stress hydrique. De manière générale, nous avons montré que les plantes appartenant à la population établie en zone semi-aride à 1 000 m d’altitude présentaient une plus grande tolérance à la sécheresse que celles appartenant aux populations des altitudes plus élevées (populations semi-humides). Ces plantes constituent donc un matériel prometteur comme candidats porte-greffe pour les greffons commerciaux de poiriers destinés à la culture dans les régions soumises fréquemment à des déficits hydriques.Fil: Zarafshar, Mehrdad. Tarbiat Modares University. Faculty of Natural Resources and Marine Sciences. Department of Forestry; IránFil: Akbarinia, Moslem. Tarbiat Modares University. Faculty of Natural Resources and Marine Sciences. Department of Forestry; IránFil: Askari, Hossein. Shahid Beheshti University, G.C. Faculty of New Technologies and Energy Engineering. Biotechnology Department; IránFil: Hosseini, Seyed Mohsen. Tarbiat Modares University. Faculty of Natural Resources and Marine Sciences. Department of Forestry; IránFil: Rahaie, Mehdi. University of Tehran. Faculty of New Science and Technology. Department of Life Science Engineering; IránFil: Struve, Daniel. Ohio State University. Department of Horticulture and Crop Science.; Estados UnidosFil: Striker, Gustavo Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura; Argentin

イランのオリエントブナ林と日本のブナ林の植生構造の比較

[論文] Articl

Plant species diversity in relation to physiographical factors at Dehsorkh Woodland

Species diversity is an important characteristic of bio-communities. Organisms diversity, diversity measurement and hypothesis test in relation to diversity causes are issues which the ecologists are interested in for long period. The aim of the trial was to study plant species diversity in Dehsorkh woodland at Javanroud, Kermanshah province, Iran. For this reason 300 sampling plots were used from which 60 at 256 m2 and 240 at 2.25 m2 area. At each plot six diversity indices (Shannon's (H), Simpson's reciprocal, Hill's N1, Pielou's (J/), Alatalo's F and Molinari's G) with respect to physiographical factors (slope, aspect and altitude) were investigated. The results showed that species diversity was the greatest at north aspects and slopes less than 30% and there was not significant difference between altitude and species diversity. The correlation between species number and indices analysis at each plot and the tendency and the role of each index at different analysis processes showed that the Simpson's reciprocal index is a best index for such research trials

PREDICTION SPATIAL PATTERNS OF WINDTHROW PHENOMENON IN DECIDUOUS TEMPERATE FORESTS USING LOGISTIC REGRESSION AND RANDOM FOREST

<div><p>ABSTRACT Forest management needs to evaluate various hazards where may cause economic or other losses to forest owners. The aim of this study is to prepare windthrow hazard maps based on logistic regression and random forest models in Nowshahr Forests, Mazandaran Province, Iran. First of all, 200 windthrow locations were identified from extensive field surveys and some reports. Out these, 140 (70%) locations were randomly selected as training data and the remaining 60 (30%) cases were used for the validation goals. In the next step, 10 predictive variables such as slope degree, slope aspect, altitude, Topographic Position Index (TPI), Topographic Wetness Index (TWI), distance to roads and skid trails, wind effect, soil texture, forest type and stand density were extracted from the spatial database. Subsequently, windthrow hazard maps were produced using logistic regression and RF models, and the results were plotted in ArcGIS. Finally, the area under the curves (AUC) and kappa coefficient were made for performance purposes. The validation of results presented that the area under the curve and kappa have a more accuracy for the random forest (97.5%, and 95%, respectively) than logistic regression (96.667%, and 93.333%, respectively) model. Therefore, this technique has more potentiality to be applied in the evaluation of windthrow phenomenon in forest ecosystems. Additionally, both models indicate that the spatial distribution of windthrow incidence likelihood is highly variable in this region. In general, the mentioned findings can be applied for management of future windthrow in favor of economic benefits and environmental preservation.</p></div

The effect of fire on some soil chemical properties of oak forests in Marivan region

Most of soil physical, chemical, mineral and biological attributes are changed by forest fires. Fire is one of the most important factors of forests destruction in Marivan region and considerable area of the region are annually exposed to fire. Depend on environmental conditions and also fire intensity, different effects will impose on ecological conditions of the environment. Whereas soil is considered as a base for forest’s growth and regeneration, study of fire effects on it’s properties takes an important place. The study area is located in 2 km far from Marivan. The study was carried out in autumn 2006 and the objective of this research was to compare the effect of fire on some soil chemical properties in surface soil (0-5 cm depth) and subsurface soil (5-20 cm depth) in a forest stand that was burned in 2002 in an area of 1.3 ha. A control stand with similar conditions was selected beside of the burned area. Five holes were dug in each site and soil samples were collected from the above mentioned depths and analyzed. Results showed significant effects of fire on most chemical attributes of surface soil including: pH, available phosphorous, electrical conductivity and available potassium increasing. The fire caused increasing of total nitrogen and cation exchangeable capacity in surface soil. All of chemical properties of subsurface soil were measured higher in burned area than control however; these differences were not significant, statistically

Impact of canopy gaps size on woody species biodiversity in mountainous forests of northern Iran (Case study: beech stands of Lalis, Chalous)

In temperate forests, disturbances are regarded as processes of great importance to forest vegetation. For the better perception of biodiversity, different indices were used in mountain forests of Lalis located in Chalous. Line transect method used for sampling, and plant abundances were recorded, as well. Forest gaps areas were divided into four classes including smaller than 200 m2,200 - 400 m2, 400 - 600 m2 and larger than 600 m2 areas. In order to analyze of biodiversity, Simpson, Shannon and Wiener, Margalef, Menhenick, Peet and Camargo indices were used. Using analysis of variance, statistical difference between biodiversity indices in respect to gap sizes was found. The maximum and minimum of divers species and richness species indices were related to very large and small gaps, respectively. The highest evenness indices were related to medium and large gaps, whereas the least of evenness indices were related to small and very large gaps

The effect of land covers on soil quality properties in the Hyrcanian regions of Iran

The present study examined the effect of land covers on some of soil quality properties. For this purpose three plantation stands (i.e., Alnus subcordata L., Poplus deltoids L. and Taxadium distichum L. Rich) and an uncultivated land (control area) were considered. Soil samples were collected at two different depths (0-15 and 15-30 cm) and characterized with respect to water content, pH, texture, total organic carbon and nutrient stocks (N, P, K, Ca and Mg). Our findings showed that the highest values of sand, clay and total organic carbon were detected in Alnus subcordata L., Poplus deltoids L. and Taxadium distichum L. Rich, respectively. Whereas the highest of pH, water content and silt were observed in the control area. Measurements of soil nutrient stocks showed that fertility decreased in relation to increased soil depth, with significant differences depending on soil depth. As a conclusion, the broad-leaved species were more successful about most of nutrient stocks than needle-leaved stand and control area

Ecological survey of Arghavan forest in north of Ilam

The aim of this study was ecological survey and site classification of Arghavan valley, north of Ilam, Iran. For this study, vegetation (tree, bush, shrub and herbaceous species), soil and physiographic factors were investigated in 57 plots. Multivariate analysis recognized four sites. Amygdalus scoparia group had positive correlation with elevation and had low species diversity. Cerasus microcarpa group had positive correlation with organic matter and negative correlation with elevation. This group had high diversity and richness. Ficus carica group was in rocky site, while Quercus brantii was in compacted soil with high clay ratio. Results showed that elevation from sea level, stone proportion of soil, soil texture and organic matter were the most important factors influencing vegetation

Presentation of management solutions for firefighting, using the decision support system at Northern Zagros forests (Case study: Marivan forests)

Intentional and unintentional fire occurrences are known as main threat factors of Zagros forests which destructed wide areas of these forests in recent years. Investigating and offering management solutions in this respect can play a controller role in tackling this crisis. The aim of the study was to identify and evaluate the most important factors influencing forest firefighting techniques in Marivan forests, using SWOT technique. Due to variation of fire control management solutions, they were classified into two categories, risk and crisis management. Identification and specification of the affecting criteria on fire control was employed, using an open answer-sheet method, based on stockholder analysis. Then the obtained results of SWOT technique were quantified by AHP approach. Results showed that employment generation and income, on-time accessibility and staff efficiency (overall weight of 0.106, 0.069 and 0.068, respectively) were identified as the most important factors affecting crisis management solutions. Furthermore, prevention of fire expanse in forest, action speed and possibility of job generation (overall weight of 0.123, 0.120 and 0.118, respectively) were identified as the most important solutions for risk management. It is recommended to: 1- reconstruct and improve the local societies morale to their surrounding environment, 2- develop the villagers culture, 3- develop national decision for natural resources conservation and finally 4- avoid absolute governmental management and administration for appropriate and scientific control of forest fire