جستجوی مقالات مرتبط با کلیدواژه « اندام های گیاهی » در نشریات گروه « کشاورزی »

Tree species have different effects on soil properties and nutrients. Plantation as a management strategy for soil productivity retention and the prevention of destruction can be effective in the continuity of forest productivity. One of the most important goals of planting coniferous species is to increase wood production, create forest parks and conservation forests. The objective of this study was to investigate the seasonal variations in nutrient concentrations in plant organs and soil of pinus brutia Ten.  stands.

For this purpose, the ​​Makhmalkuh forest park in Lorestan province was selected and in 1396, random sampling was performed using 5 (400 m2) sample plots. In each sample plot, an indicator tree pinus brutia Ten. was selected and its young and perennial leaves and twigs were sampled in the upper third of the crown in four seasons, as well as from two depths of 0-5 and 5-15 cm a mixed soil sample was taken in each sample plot. Soil texture, pH, organic carbon (C), total nitrogen (N), available phosphorus (P), and potassium (K), for all samples were measured in the laboratory. The soil parameters, nutrients of soil and plants organs were analyzed by using one-way analysis (ANOVA) and Duncan test procedures among different seasons.

According to the results, the lowest amount of dry weight and percentage of moisture in all four organs was observed in summer and the highest amount was observed in winter. Based on the results, there was a significant difference between the nutrient concentrations of plant organs in different seasons (sig<0.01). In all four organs, the highest amount of nitrogen was recorded in spring, potassium in winter and phosphorus in summer. The results of correlation studies also showed a significant relationship between nutrient concentrations of different organs and different soil characteristics.

High amounts of nitrogen and phosphorus in the spring can be argued that increasing the temperature in most cases increases the metabolic activity in the soil, evaporation and transpiration and absorption of nutrients. Different climatic conditions in different seasons, lack of soil moisture, retranslocation of nutrients from perennial needles and branches to young parts and seasonal and monthly changes in the chemical composition of the throughfall can be the most important reasons for these changes.

Introduction:

Climate change and global warming are the most important challenges in sustainable development, which is due to increased concentration of greenhouse gases in the atmosphere. Carbon dioxide is a major component of greenhouse gases. In order to reduce atmospheric carbon dioxide and to create a balance in the content of greenhouse gases, atmospheric carbon must be absorbed in organic forms (Dieleman et al., 2015; Lichtfouse, 2009). For this aim, a study was done in agricultural lands of Gorgan in order to estimate the carbon sequestration potential of soybean plant (Glycine max L.).

This research was carried out in 150 soybean fields of Gorgan township and sampled by quadrate 0.5Í0.5 m2 as random method, during 2016-2017. The soybean shoot and root organs were individually harvested and transferred to the laboratory. An electric burn furnace method was used to determine the carbon sequestration potential in soybean organs (including pods, seeds, stems, leaves and roots). Also, the amount of shoot to root and harvest index were estimated to determine the net primary production based on carbon content in the above ground organ, below ground organ and total plant, and the carbon allocation coefficients in each soybean organ. Then, using different interpolation methods, the spatial distribution of carbon sequestration of the plant organs was investigated in ArcGIS software. All data were analyzed by SPSS software.

The results showed that Kriging method was the best model for carbon interpolation and distribution of carbon sequestration potential in agricultural lands of Gorgan township. The amount of stored carbon was obtained as 579.64 kg.ha-1 in leaves, 744.81 kg.ha-1 in stem, 881.16 kg.ha-1 in seeds, 340.16 kg.ha-1 in pods and 540.21 kg.ha-1 in root. Also, according to harvest index (32%) and grain yield (3461.13 kg.ha-1), other indexes were calculates as the ratio of shoot to root about 4.30, the total net primary carbon production 6734.8 kg.ha-1, above-ground net primary carbon production 4867.2 kg.ha-1 and below-ground net primary carbon production about 1867.63 kg.ha-1. Also, the shares of the allocation coefficients of economic organs, stems, leaves, root and root secretions were 0.23, 0.49, 0.61 and 0.12, respectively. The zoning results showed that the total stored carbon potential in soybean plant was highest in the eastern, north and southeastern regions of the surveyed area, and the central, western and southwestern parts of this township had the lowest stored carbon potential. Also, the amount of carbon sequestration potential (total above ground and below ground organs) was as 3085.98 kg.ha-1 in this study.

 The highest proportion of carbon was allocated to the shoot organs, and the carbon of root exudates was also lower than other plant organs. In this study, it has been found that the potential of carbon sequestration was different in soybean plant organs and some variable such as agronomical management, soil and climatic condition can affect on its contents.AcknowledgementsWe are thankful to Gorgan University of Agricultural Sciences and Natural Resources (GUASNR), Agriculture Services Centers of Gorgan and soybean farmers for all their companions and supports.

Carbon sequestration in plant organs is one of the most important ways to reduce atmospheric CO2 and also to reduce greenhouse effect and climate change. In order to investigate the effect of conventional and conservation cropping systems on carbon sequestration potential in soybean plant organs as an ecosystem service, a study was conducted in agricultural lands of Gorgan city during 2014-15.

In this study, 48 soybean fields were selected in the main directions of Gorgan city and sampling was carried out using W method during physiological ripe (late November). An electric burn furnace method was used to determine the amount of stored carbon. The stored carbon content was determined individually in soybean organs including root, stem, leaf, pod and seed. The weight of each plant organ was estimated per unit area, then using the carbon sequestration coefficient, the total amounts of carbon sequestration per unit area was obtained.

The average amount of carbon in soybean plant was estimated as 3281.4 kg/ha under the conventional cropping system and 3176.1 kg/ha under conservation cropping system. The reason for this result was the higher yield of plant biomass in conventional cropping system. Similar results were found for plant organs, so that the average amount of carbon were 1181.6 and 1249.3 kg/h seed, 792.19 and 710.27 kg/ha in leaves, 968.61 and 888.85 kg/ha in stem, 69.20 and 87.12 kg/ha in pods and 269.81 and 249.57 kg/ha in roots under conventional and conservation cropping systems, respectively. Results showed that there was a significant different between the amounts of carbon sequestration in the above ground and below ground organs of soybean. The carbon sequestration amounts were about 2993.8 kg/ha in above ground organs and about 265.59 kg/ha in the below ground organs.

In this study, it has been found that the potential of carbon sequestration in soybean plant organs is similar in conventional plant system and conservation farming system. Results showed that there was a significant different between the amounts of carbon sequestration in the above ground and below ground organs of soybean. The carbon sequestration amounts were about 2993.8 kg/ha in above ground organs and about 265.59 kg/ha in the below ground organs.

In this study, it has been found that the potential of carbon sequestration in soybean plant organs is similar in conventional plant system and conservation farming system. Keywords: Soybean, Conservation cropping system, Carbon Sequestration, Plant organs

The present study was conducted to evaluate the potential of carbon sequestration in plant organs (root, stem and leaf) of Zygophyllum atriplicoides and Gymnocarpus decander and soil at two depths (0-15 and 15-30cm). The experiment was conducted in the Saleh-Abad region, 41km north of Haji-Abad, Bandar-Abbas Hormozgan, Iran, during 2012. Sampling of plant organs was performed by separating the leaf, stem and root. After determining the average dry weight of the study species, the content of organic carbon was calculated for both plant and soil. This study was carried out in two separate factorial experiments arranged using a randomized complete design. The first factor was the type of plant species in both experiments. The second factor was the plant organs in experiment I and different soil depths in experiment II. The results showed that the highest carbon sequestration was obtained at 0-15 cm soil depth. The effects of plant species and plant organs on the content of carbon stored in plant tissues was significant (P ≤0.05) and (P ≤0.01), respectively, while the interaction of those two factors had no significant effect on stored carbon. A significant difference was found between plant organs in terms of stored carbon. In both plants, the highest and lowest content of stored carbon was observed in stem and root, respectively. According to the results, the carbon content stored in Z. atriplicoides (45.09 Kg) was 10.7% more than that of G. decander (40.74 Kg). Overall, the results of this study indicated that the highest carbon sequestration was obtained with Z. atriplicoides in the Saleh-Abad region.

Aquatic plants are irreplaceable biological filters due to their uptaking high potential of heavy metal, accumulating and having tolerance for contaminated water ecosystems. The purpose of this research was to evaluate the heavy metal pollution (Cu, Pb, Zn and Cd) in underground organs, stems, and leaves of Phragmites australis as well as sediment samples of Dez river catchment, in Dezful, Iran. The sample preparation carried out with 4:1 compound nitric acid and percholoric acid before heavy metal measurement by Atomic Absorption Spectroscopy. The results pointed out that the concentrations of Cu, Pb, Zn and Cd in sediment samples were 12.021, 12.982, 108.485, and 0.189, respectively. The values of Cu (1.903, 3.780 and 7.217 g/g), Pb (0.265, 0.585 and 2.674 g/g), and Cd (0.052, 0.120 and 0.275 g/g) in stems, leaves and underground organs were relatively lower than toxicity level. However, Zn concentration was considerably high in stems (30.790 g/g), leaves (44.981 g/g ), and underground organs (52.216 g/g) comparing to toxicity level. . The maximum concentration of metals was found in the underground organs of plants. In fact, mean concentration in the organs of Common reed follows like this: underground> leaves> stems, suggesting that the low mobility of these elements in underground organs towards aerial parts. The high translocation factor value for Zn can indicate a high ability to move within the plant parts. In conclusion, common reed can be recommended as bio-accumulator and absorbent in heavy metal contaminated water ecosystems.