Reza Erfanzadeh; Fatemeh-al-Sadat Hosseini; Seyed Homzeh Hosseini Kahnuj
Abstract
In this study, the effect of the canopy of Pteropyrum aucheri on the soil seed bank was investigated in southern Kerman province, Sehchah village rangelands. By studying the seed bank at two depths of 0-5 and 5-10 cm under and outside the canopy of this shrub species, the potential of the soil seed bank ...
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In this study, the effect of the canopy of Pteropyrum aucheri on the soil seed bank was investigated in southern Kerman province, Sehchah village rangelands. By studying the seed bank at two depths of 0-5 and 5-10 cm under and outside the canopy of this shrub species, the potential of the soil seed bank in preserving and recovering of the valuable medicinal species Pergularia tomentosa was evaluated. For this purpose, 15 individuals of the P. aucheri were selected in which P. tomentosa could also be observed under the canopy of P. aucheri. Soil sampling was carried out from under and outside the canopy from both depths, totally of 60 samples. Under the canopy (and also outside the canopy), 10 soil augers were taken. The soil samples were transferred to the greenhouse in Faculty of Natural Resources, Tarbiat Modares University, and the species present in the soil were identified using the seed germination method. In the greenhouse cultivation, a total of 2164 seeds germinated. Of these, 1486 seeds belonged to the under-canopy (1156 seeds at the upper depth and 330 seeds at the lower depth) and 678 seeds belonged to the outside of the canopy (341 seeds at the upper depth and 337 seeds at the lower depth). The density of the seed bank at the upper depth was significantly higher in the under-canopy than outside the canopy. This study showed that the valuable species of P. tomentosa not only had a seed bank under the canopy but also did not form a canopy outside the canopy of P. aucheri. Therefore, for the conservation and restoration of this species, it is not possible to rely on soil seed bank.
Hossein Arzani; vahideh Abdollahi; Javad Motamedi; Majid Akhshi
Abstract
Nowadays, most attention is focused on physical and non-destructive methods, such as NIRS, to measure the chemical composition of rangeland species. Therefore, the purpose of this study is to provide calibration models for Infrared NIRS to estimate the forage quality of shrub species, so that in addition ...
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Nowadays, most attention is focused on physical and non-destructive methods, such as NIRS, to measure the chemical composition of rangeland species. Therefore, the purpose of this study is to provide calibration models for Infrared NIRS to estimate the forage quality of shrub species, so that in addition to saving time and cost, the quality of these plants could be estimated with proper accuracy. For this purpose, 654 samples of vegetative, flowering and seeding stages were irradiated by the DA7200 Perten Instrument to estimate the values of nitrogen (N), crude protein (CP), acid detergent fiber (ADF), dry matter digestiblility (DMD) and metabolizable energy (ME) via NIRS. Then, the data were transferred to the Unscrambler software for multivariate analysis. Before fitting the model, S.Golay and SNV methods were used for normalization of data distribution. Calibration and validation of model were performed using PLS1 method and Cross Validation method, respectively. Then, the predictability of models was evaluated by considering the calibration statistics. A total of 18 calibration programs were developed. Considering the calibration statistics, it could be said that the coefficient of determination was above 80% in all the factors studied. Also, at all growth stages, the correlation coefficient between the reference data and the data estimated by NIR was above 90%. Our results clearly showed that NIR calibrations obtained in this study could be used in current and future programs to assess the forage quality of shrub species used by livestock.
