Wyniki wyszukiwania - BazTech

1

Range of soil and climate characteristics appropriate for Pistacia atlantica forest development and rehabilitation (case study: Fars province, Iran)

Nejabat M., Negahdarsaber M., Ghahari G.

Journal of Water and Land Development

|

2017

|

no. 32

71--78

EN

Investigation of ranges of soil and climate characteristics appropriate for the tolerant species: Pistacia atlantica subsp. mutica according to field study was the main objective of this research. This study was carried out based on random sampling across 20×20 km wild pistachio forests of Fars province (Iran). Results showed that mountainous and hilly lands are the main land types that pistachio species have evolved on. Statistical analysis of physical and chemical soil characteristics based on principal component analysis (PCA) method showed that wide ranges in soil characteristics, even up to about 40% differentiation in some measured properties, did not restricts this subspecies natural growth. The main growth limiting factors were shallow soil depth and light soil texture that decreased storage capacity of soil moisture, necessary for wild pistachios survival during drought and long dry periods. Climatic elements were analysed through the same approach and showed that temperature, precipitation and wind with overall variability of 85.9% were the most effectual factors. Pistacia atlantica subsp. mutica is one of the species refractory to various soil conditions and adapted to weak soils for the establishment and rehabilitation of forests in semi-arid regions.

PL

Głównym celem badań terenowych prezentowanych w niniejszej pracy było przeanalizowanie zakresu wartości charakterystyk glebowych i klimatycznych odpowiednich dla podgatunku Pistacia atlantica subsp. mutica. Próby pobierano losowo z poletka w lesie pistacjowym o wymiarach 20×20 km w prowincji Fars w Iranie. Wyniki dowodzą, że pistacja wyewoluowała na ziemiach górskich i na terenach pagórkowatych. Statystyczna analiza fizycznych i chemicznych właściwości gleb prowadzona metodą składowych głównych (PCA) wykazała, że duża zmienność badanych cech, sięgająca w niektórych przypadkach 40%, nie ograniczała naturalnego wzrostu badanego podgatunku. Głównymi czynnikami ograniczającymi były płytkie gleby o lekkiej strukturze, które zmniejszały zdolność gleb do zatrzymywania wilgoci niezbędnej dziko rosnącej pistacji do przetrwania długich okresów suszy. Czynniki klimatyczne analizowano tą samą metodą i stwierdzono, że najbardziej istotne były temperatura, opady i wiatr o ogólnej zmienności 85,9%. Pistacia atlantica subsp. mutica jest jednym z gatunków najbardziej odpornych na różne warunki glebowe, co może mieć znaczenie dla stabilizowania i rekultywacji lasów na terenach półpustynnych.

2

Determining the relation between soil properties and spatial variability of Nitraria schoberi Linn. using geostatistical analysis: a case study in Meighan Playa in Iran

Tilaki G. A. D., Kamarei R., Vafakhah M.

Polish Journal of Ecology

|

2013

|

Vol. 61, nr 1

93--104

EN

This study is an assessment of the relation of the spatial variability of Nitraria schoberi Linn. to the soil properties conducted by using geo-statistical analysis. In an area of 140 ha a regular network from a semi-arid region of Meighan Playa in central Iran was selected. The results showed that statistically most of the variables fit spherical, exponential and Gaussian models. The lowest and the highest coefficients of variation were found with the soil pH (27%) and the density (66%) of Nitraria schoberi, respectively. The semi-variogram analysis showed that the effective range fluctuated from 150 m for silt to 2563.43 m for the acidity of the soil. The electronic conductivity and soil texture showed more spatial dependency than the organic matter.

3

Quaternary aquifer transmissivity derived from vertical electrical sounding measurements in the semi-arid Khanasser Valley Region, Syria

Asfahani J.

Acta Geophysica

|

2012

|

Vol. 60, no. 4

1143-1158

EN

Vertical electrical sounding technique (VES) is used as an alternative approach to pumping test for computing the Quaternary aquifer transmissivity in the Khanasser Valley, Northern Syria. The method is inexpensive, easy and gives faster results with higher special resolution than the traditional pumping technique. The hydraulic conductivity values obtained using VES agree with the pumping test results, which in the Khanasser Valley vary between the order of 0.864 and 8.64 m/day (10–5 and 10–4 m/s). The probable location of the Quaternary aquifer in the Khanasser Valley is obtained through the transmissivity map derived from VES. The knowledge of transmissivity is fundamental for modeling and management processes in the Khanasser Valley. Other similar semiarid regions can benefit from the approach successfully applied in the study area.

4

Short to medium - term gully development : Human activity and gully erosion variability in selected Spanish gully catchments

Marzolff I., Poesen J., Ries J. B.

Landform Analysis

|

2011

|

Vol. 17

111-116

EN

This study investigates how medium-term gully-development data differ from short-term data, and which factors are responsible for their spatial and temporal variability. Eight actively retreating bank gullies situated in Spanish basin landscapes were monitored for up to 11 years with high-resolution aerial photographs using unmanned remote-controlled platforms. The results of planimetric and volumetric change analysis using GIS and photogrammetry systems show a high variability of annual gully retreat rates both between gullies and between observation periods. The varying influences of land use and human activities with their positive or negative effects on runoff production and connectivity appears to play the most important role in these study areas, both for short-term variability and medium-term difference in gully development. The study demonstrates the importance of capturing spatially continuous, high-resolution three-dimensional data for detailed gully monitoring. It also confirms that short-term data are not representative of longer-term gully development, but they are still required to understand the processes - particularly human activity at varying time scales - causing gully-erosion variability.

5

Electrical resistivity investigations for guiding and controlling fresh water well drilling in semi-arid region in Khanasser Valley, Northern Syria

Asfahani J.

Acta Geophysica

|

2011

|

Vol. 59, no. 1

139-154

EN

Electrical resistivity survey is conducted in the Khanasser Valley, considered as a semi-arid region in Northern Syria, to guide and control fresh water well drilling. Vertical Electrical Soundings (VES) are carried out near the existing wells, which were also used to measure salinity and conductivity of water samplings. Resistivity and hydrogeological data combination made it possible to establish empirical relationships between earth resistivity, water resistivity, and the amount of total dissolved solids (TDS). These relationships are used in the present research in order to follow the TDS salinity variations, both in lateral and depth directions, along the longitudinal profile LP3, located in Khanasser Valley. Apparent salinity map under this profile is established for Quaternary and Paleogene deposits, and boundaries of suitable areas for fresh water well drilling in the totality of the Khanasser Valley are drawn. It was shown that excessive fresh-water depletion may affect the groundwater quality by upward seepage of saline water. Therefore, it is important to keep the fresh-salt water interface in a stationary situation. The geoelectrical methods widely contribute in determining the position of such interface, and can be easily applied in similar arid areas.