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The use of waste water for irrigation is on the rise, particularly in peri-urban areas of developing countries. Effects of municipal waste water application on soil and eldar pine (Pinus eldarica Medw.) trees were studied. Two areas irrigated by municipal waste water and well water (for at least 15 years) were selected south of Tehran, Iran. Data was collected using the technique of systematic random sampling with 4 replicates in either or both fields. Observations included the measurement of tree diameter at breast height (d.b.h.), total height, crown length, average crown diameter, basal area and standing volume, needle mineral composition and changes in soil properties. Application of municipal waste water produced better growth in P. eldarica as compared with well water. Concentrations of N, P, K, Ca, Mg, Na, Cu, Fe, Mn, Zn as well as the values of pH, EC, SOC, CaCO3 were greater in needles of trees irrigated with municipal waste water than of those with well water. All measured parameters of soil showed their greatest values in the upper layer of soil (0-0.15 m). Irrigation using municipal waste water did not result in toxicity of elements of needles and soil. This study confirms that municipal waste water could be utilized as an important source of water and nutrients in growing P. eldarica to increase biomass production.
Darkling beetles (Coleoptera: Tenebrionidae) are one of the most numerous and diverse family of beetles, present in almost all agroecosystems. The fauna of these beneficial insects in chain foods of ecosystems was studied in Iranian rice fields and surrounding grasslands. The results show a total of 21 tenebrionid species of 16 genera including, Zophosis LATREILLE, Dailognatha ESCHSCHOLTZ, Tentyria LATREILLE, Eutagenia REITTER, Phymatiotris SOLIER, Pachyscelis SOLIER, Pimelia FABRICIUS, Dendarus DEJEAN, Colpotus MULSANT et REY, Gonocephalum SOLIER, Opatroides BRULLÉ, Blaps FABRICIUS, Cephalostenus SOLIER, Probaticus SEIDLITZ, Euboeus BOIELDIEU and Tribolium MACLEAY. Altogether, members of 3 subfamilies (Pimeliinae, Opatrinae, Tenebrioninae) were collected from Iranian rice fields and surrounding grasslands. Four genera and 14 species are new records for Iran.
For native species, mixed plantation systems seem to be the most appropriate for providing a broader range of options such as production, protection, biodiversity conservation and restoration. After 11 years, growth and nutrition and soil properties were examined in young plantation of two indigenous tree species in Hyrcanian forests of Iran. Quercus castaneifolia C.A. Mey. (as target species) and Celtis australis L. (as native component species) were planted in five proportions (100Q, 70Q:30C, 60Q:40C, 50Q:50C, 40Q:60C) in Noor, Iran. Diameter at breast height of individual Quercus trees and total basal area were affected by the presence of Celtis. Percent retranslocation of nutrients in Quercus followed in order: K> P> N. Leaf-litter fall production ranged from 4.10 to 6.14 t ha⁻¹ year⁻¹. Ca and Mg concentrations in fully expanded leaves of Quercus, N and K retranslocation of Quercus, concentration of available P in soil were higher in some of the mixed plantations than in monoculture of Quercus. On the other hand, N concentration in fully expanded leaves of Quercus, N fluxes and soil C/N ratio were higher in monoculture of Quercus. Within the framework of this experiment, it appeared that production was maximized when these two species were grown together in the proportion of 60% Quercus and 40% Celtis.
The primarily goal of plot-less sampling methods is to reduce costs and rapid survey of plant communities. First full inventory was conducted in two 30-ha sites of Saxaul populations geo-morphologically different. In first site (site I), population had random pattern while in second site (site II) clumped pattern was observed. Crown diameters and spatial situation of all trees were recorded using distance and azimuth. Data were transferred to computer and stem map was generated with ArcGIS Software. Distance sampling methods include point-centred quarter method (PCQ), joint-point method (JP), Random pairs method (RP), T-Square method (T-Sq) and Quartered neighbour methods beside fixed area plot (FAP), n-tree and variable area transect (VAT) methods were conducted on generated stem maps. A time study was done aiding indices determined in field works. In site I, point centred quarter estimator with measurements to the second closest individual in each quadrant had the lowest relative bias (RBIAS) in estimating density followed by 3-tree and closest individual methods. In clumped pattern (site II), variable area transect method with measurements to the 4th and 5th closest individuals in each transect brought the best results. The most time consuming methods after fixed area plot, were point centred quarter estimators while methods considering measurement to the closest individual were rapid. Considering RBIAS and Time together, VAT method was the best sampling method in clumped pattern followed by point centred quarter estimator with measurements to the second closest individual in each quadrant and closest individual estimators. In random pattern, point centred quarter estimator with measurements to the second closest individual in each quadrant was the best method followed by 3-tree and closest individual estimators. But for estimating cover per unit area N-tree methods performed well. As in this site, VAT method located in 4th grade, and due to simplicity of field works related to this method, in the case that the investigator would not be able to clearly define spatial pattern of the population, this method can be recommended as well.
The assessment of the density and cover of very scarce vegetation in dry habitats may create methodological problems. The variable area transect method (VAT ) is a potential labour-saving sampling method and an alternative to plot (quadrate) method. It allows for density estimation without the time-consuming studies associated with other plot-less density estimators. We used the method in a natural shrubland of Saxaul (Haloxylon ammodenderon C.A.M) to define optimum parameters include transect width and individual’s number to which, distance is measured. Three transect widths were chosen, 10-m, 15-m and 20-m and distances to the 3rd, 4th and 5th individual. Transect width affected the estimation, a 20-m width transect had the least relative bias (–0.5%), and a 10-m width sampling had the greatest bias (–20%). However, all methods underestimated the plant density. The most accurate estimation was with the 3rd plant distance and 20-m transect. As the VAT method is more efficient per unit effort in the field than the quadrate methods, it can be recommended for rapid assessment of desert communities density (like saxaul) especially when plants are dispersed at random.
The leaf morphology of Buxus hyrcana (Pojark.), shade-tolerant and evergreen species growing in understorey of Caspian Forest was studied in five natural Iranian populations in order to recognize the pattern of within- and among-population variation of selected leaf morphological traits. Fifteen traits were selected and measured or calculated – list in Appendix. Leaves were collected from different geographical (between 36°13′N and 53°15′E) populations of B. hyrcana growing in the Caspian Forests located in Mazandaran Province (northern Iran) in the similar vegetation and site conditions but on different altitudes. Ten mature trees from five relatively small areas (0.5–1 ha) were selected in June. Then ANOVA model was used with both crossed and nested effects. The results showed that variation among the populations was significant in 13 of 15 traits (P <0.05); variation among the trees in the population was significant in 14 of 15 traits (P <0.05). Among all characters measured, the greatest plasticity was found for weight, leaf area mass and specific leaf mass. Function 1 explained 30% of the total variance and Function 2 represented another 17% of the total variance. PCA analysis showed that the most important role in function 1 allocated to width of lamina and leaf figure ratio (length of lamina/width of lamina) and in function 2 to top of leaf figure (width of lamina in 0.1 its length/width of lamina). The results of the average linkage clustering method evidenced four distinct clusters. Generally, morphological traits of leaves of B. hyrcana showed low variation among the considered populations based on clustering analysis, although some trees inside the population showed significantly different values in comparison with other trees.
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