Physiographic-Tectonic Zoning of Iran’s Sedimentary Basins

Base on geological history evaluation using regional stratigraphy, sedimentary environments, magmatic activities, metamorphism and structural trend in Iran, physiographic-tectonic zoning map of Iran’s sedimentary basins has prepared. This map has prepared to point out the basement tectonics role in Iran. It contains twenty-four different provinces. Iran has composed from different plates: Arabian plate in south and west, Cimmerian manipulated in north and east, Eurasian plate in northeast margin. Cimmerian manipulated at least can be divided to the smaller part, East-Central Iran and North-Central Iran microcontinents. There are evidences for thick-skinned tectonics in the border zones of these plates and microcontinents, especially in Sanandaj-Sirjan overthrust belts that it formed by crustal stacking wedges. Also, Neoproterozoic-Phanerozoic Tectonic column in the Arabian, Cimmerian and Eurasian plates under Iran Country area have introduced.

Effect of physiographic factors on qualitative and quantitative charac-teristics of Cornus mas L. natural stands in Arasbaran forests, Iran

Arasbaran forests are located in East Azerbaijan （northwest Iran）. Increasing of socio-economic problems in this area causes destruction of biodiversity and structure of these forests. Using multipurpose trees such as cornelian cherry （Cornus mas L） to encourage villagers to produce forest by-products is a basic approach for preserving these forests. This species grows naturally in Arasbaran forests and the fruit is annually exploited using traditional harvest methods. This study aims to assess the ecological requirements of cornelian cherry and the important factors affecting its distribution. For this purpose, 40 circular sampling plots （300 m2） on various slope aspects were demarcated for sampling the occurrence of cornelian cherry in forest stands. DBH and crown cover percentage on north aspects were significantly greater than on other aspects and 4.5% of all trees were cornelian cherry in mature forest stands. North aspects had more seed-origin trees （standards） of cornelian cherry than coppiced trees, while west facing aspects had more coppiced than standard trees. This species had the highest regeneration rate in the sapling stage of 0–2.5 cm DBH. Thus, I recommend cultivation and development of cornelian cherry as a multi-purpose tree in the Arasbaran region on degraded forest lands on north and west aspects.

Changes in climatic conditions drive variations in arbuscular mycorrhizal fungi diversity and composition in semi-arid oak forests

Arbuscular mycorrhizal fungi(AMF)play a vital role in plant productivity and ecosystem functions.However,their responses to abiotic factors(i.e.,climate,physiography,and soil properties)are unknown,especially across climatic gradients and slope aspects in arid and semi-arid ecosys-tems.In this study,using 60 composite soil samples,direct and indirect effects of climate factors and slope aspects on AMF diversity,composition and spore density were studied.The findings indicate that climate has a more direct influ-ence on soil properties(P<0.001)in comparison to slope aspect(P=0.449).In contrast,climate significantly affected AMF diversity and composition,with the highest diversity in dryer areas.Soil pH had the highest correlation with different facets of AMF diversity.Structural equation modeling(SEM)indicated that only a small part of the variation in AMF diversity and spore density could be explained by climate characteristics,slope aspect and soil properties.Based on SEM results,climate was the most important determinant of AMF diversity and spore density;slope aspect had a less critical role.The outputs suggest that variations in AMF diversity are derived by the direct effects of climate and the indirect effect of soil chemical properties.In addition,with increasing dryness,sporulation and AMF diversity increased.

Modeled Implications of Global Warming Conditions on Precipitation Totals in Valley and Highland Areas of Nigeria

Global temperature has been increasing causing differences in precipitation response in different physiographic regions as feedback mechanism. The aim of this work is to model the implications of the global warming conditions on precipitation occurrences in the valley and highland areas of Nigeria. Harmonic analysis on the average monthly rainfall observations was performed for 56 years (1961-2016) using the Turbo Pascal for windows programming language in order to implement the computation. This was carried out by fitting a periodic function of sinusoidal character to enhance the determination of the contribution of each harmonic, the amplitude of each harmonic and the time at which each harmonic is maximum. The result of harmonic plots of the grand average monthly rainfall for the valley area of Makurdi and highland area of Jos shows that there exists a similarity in the trend of variations of harmonic series plots of the data as either plots exhibit single rainfall maxima or peak, meaning that rainfall patterns are mono-modal in nature. Modeled result of average monthly rainfall for the valley area of Makurdi shows an increase in rainfall occurrences from the month of January to August but a decrease from September to December, meaning an expectation of more rains immediately after onsets and lesser rains before cessations. The modeled result for the highland area of Jos however shows a decrease in the occurrence of rainfall in the months of January and February but an increase from the month of March to December. The implication is that there will be water deficiency for late crops and aquifer recharge in the valley areas while highland areas will experience delayed onset of agricultural calendar. The study recommends timely release and adherence to weather/climate forecasts.

Ecological and Chemotypic Analysis for Improved Growth and Management of Naturally Occurring Black Cohosh (<i>Actaea racemosa</i>L.) Populations in Western Maryland

Black cohosh (Actaea racemosa L.) is a perennial herb native to deciduous woodlands in eastern North America with an extensive history of traditional use, most commonly for rheumatoid arthritis and female reproductive issues. Modern clinical research has maintained this herb’s relevance into the 21st century with a majority of authentic black cohosh raw material still harvested from naturally occurring populations in Appalachian woodlands for use in botanical supplements. Increased use and interest in black cohosh have led to increased wild harvesting, reports of adulteration, and stress on this important natural resource. In an effort to study this significant medicinal plant as part of an ecosystem, and to understand factors that would contribute to the more effective growth and maintenance of black cohosh, key chemical, physiological, and ecological aspects of two occurring populations in western Maryland were surveyed. Rhizomes were harvested from six populations of naturally occurring black cohosh in two state forests located in the Allegheny Plateau and Ridge and Valley physiogeographic provinces of Maryland. The concentrations of five medicinal compounds found in black cohosh extracts, actein, 23-epi-26-deoxyactein, cafeic acid, ferulicacid, and N-methylserotonin, were compared with plant reproductive status as well as accompanying overstory and under story species, soil moisture, and soil pH at each site. Compound levels showed a complex dependence on physiography but were independent of reproductive state. The findings provide clues to guide efforts at effective growth and management of wild populations of black cohosh and other threatened medicinal plants.

The influence of large dams building on resettlement in the Upper Mekong River

This paper seeks to quantify the social and economic impact of resettlement based on the physiographic element changes post relocation. We focus on communities affected by the Nuozhadu hydropower project, the largest existing hydropower project on the mainstream of the Upper Mekong River. Soil and meteorological data were collected from the Soil Spatial Database and the China Terrestrial Ecological Information Spatial Meteorology Database, while social and economic data were collected via field surveys. We have three major con- clusions： （1） Communities will be relocated to a new climate and new elevation, moving from a north tropical climate zone under 700 m to a subtropical climate zone above 700 m. （2） Physiographic element changes due to relocation will reduce household economic income. After relocation, the annual family income of the Shidaimao group decreased by 62%; the annual family income of the other 5 study groups （Lasa, Hani, Nochangchangyi, Mengsa, and Dawazi） dropped by 65%. （3） Communities relocated across the study township are 61.1% less connected with their former relatives after relocation while family-to-family free labor exchange, a previous community norm, decreased by 91%. China＇s dam resettlement compensation system focuses on the loss of economic resources after relocation. However, this study finds that the physiographic elements of the relocation sites are an important driver of ensuring economic growth and stability after relocation. As a result, we recommend more attention be paid to physiographic continuity when designing relocation models.