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91.
Sajjad Hosseinzadeh Monfared Mohammad Matinizadeh Anoushirvan Shirvany Ghavamedin Zahedi Amiri Reza Mousavi Fard Fariba Rostami 《林业研究》2013,24(2):391-395
Plants are capable of reducing environmental pollutions through uptaking contaminants in their tissues. In the study site, twenty one-year-old leaves and shoots as well as twenty soil samples were sampled and analyzed by Inductively Coupled Plasma (ICP). We investigated the uptaking ability of lead (Pb) and cadmium (Cd) by the leaves and shoots of Platanus orientalis, Robinia pseudoacacia and Fraxinus rotundifolia in Karaj city, the western Tehran, Iran. We also evaluated the total metal accumulation capacity by using metal accumulation index (MAI). Results indicated that there was no significant difference in uptaking contents of Cd and Pb in the leaves among the trees. However accumulation of Cd in shoots of F. rotundifolia and R. pseudoacacia was significantly higher than that of P. orientalis. The accumulation of Pb in shoots of R. pseudoacacia was significantly higher than the other species. The amount of Pb in the soil of the study area was significantly higher than Cd. Concentrations of Cd and Pb in leaves of the three species are in the ranges of 2.4 2.7 mg Kg-1 and 7.1 14.4 mg Kg-1 , respectively. R. pseudoacacia had the highest MAI value for leaves (2.21) and F. rotundifolia had the highest MAI value for shoots (2.4). 相似文献
92.
Hossain Mohammad M. Scott Ian M. McGarvey Brian D. Conn Kenneth Ferrante Lorenzo Berruti Franco Briens Cedric 《Journal of pest science》2015,88(1):171-179
Journal of Pest Science - Conflicting views regarding synthetic pesticides include the successful use as pest management tools for agriculture and forestry on one hand and the threats to components... 相似文献
93.
94.
Morteza Pourreza Seyed Mohsen Hosseini Ali Akbar Safari Sinegani Mohammad Matinizadeh Seyed Jalil Alavai 《林业研究》2014,25(1):113-120
Zagros forests are mainly covered byQuercus brantii L. coppices and oak sprout clumps occupy the forest area like patches. We investigated post-fire herbaceous diversity in the first growing season after fire. For this purpose neighboring burned and unburned areas were selected with the same plant species and ecological conditions. The data were collected from areas subjected to different fire severities. Overall 6 treatments were considered with respect to fire severity and the mi-crosites of inside and outside of oak sprout clumps including: unburned inside and outside of sprout clumps (Ni and No), inside of sprout clumps that burned with high fire severity (H), inside of sprout clumps that burned with moderate fire severity (M), outside of sprout clumps that burned with low fire severity (OH and OM). Different herbaceous com-position was observed in the unburned inside and outside of oak sprout clumps. The species diversity and richness were increased in treatments burned with low and moderate fire severity. However, in treatment burned with high fire severity (H), herbaceous cover was reduced, even-ness was increased, and richness and diversity were not significantly changed. We concluded that besides the microsites conditions in forest, fire severity is an inseparable part of the ecological effect of fire on her-baceous composition. 相似文献
95.
Mukhlesur Rahman M Parvin S Ekramul Haque M Ekramul Islam M Mosaddik MA 《Fitoterapia》2005,76(5):484-489
Annotemoyin-1, Annotemoyin-2, squamocin and cholesteryl glucopyranoside were isolated from the seeds of Annona squamosa. These compounds and plant extracts showed remarkable antimicrobial and cytotoxic activities. 相似文献
96.
Information on population genetic structure and crop genetic diversity is important for genetically improving crop species and conserving threatened species. The PAL gene sequence is part of a multigene family that can be utilized to design DNA marker systems for genetic diversity and population structure investigation. In the current study, genetic diversity and population structure of 100 accessions of wild Pistacia species were investigated with 78 PAL markers. A protocol for using PAL sequences as DNA markers was developed. A total of 313 PAL loci were recognized, showing 100% polymorphism for PAL markers. The PAL markers produced relatively more observed and effective alleles in Pistacia falcata and Pistacia atlantica, with a higher Shannon’s information index and expected heterozygosity in P. atlantica, Pistacia vera and Pistacia mutica. Pairwise assessment of Nei’s genetic distance and genetic identity between populations revealed a close association between geographically isolated populations of Pistacia khinjuk and Pistacia chinensis. The accessions of wild Pistacia species had more genetic relationship among studied groups of species. Analysis of molecular variance indicated 19% among-population variation and 81% within-population variation for the PAL gene based DNA marker. Population structure analysis based on PAL revealed four groups with high genetic admixture among populations. The results establish PAL markers as a functional DNA marker system and provide important genetic information about accessions from wild populations of Pistacia species. 相似文献
97.
Prolific and rapid in vitro plant organogenesis via direct regeneration has been obtained from axenic seedling-derived petiole and leaf explants of Ficus religiosa in Murashige and Skoog (MS) medium containing different concentrations of cytokinins in combination with indole-3-butyric acid (IBA). MS medium with 1.5 mg/l 6-benzylaminopurine plus 0.15 mg/l IBA produced the highest shoot induction frequency with an average of 6.26 and 10.13 shoots per leaf and petiole explants, respectively. After 4 weeks, the highest root formation frequency (96.7%), root number (5.73), and root length (4.76 cm) were with MS medium containing 2.0 mg/l IBA plus 0.1 mg/l α-naphthalene acetic acid. In addition, the effect of four sodium nitroprusside (SNP) treatments on acclimatization was also studied. Highest morphological traits such as survival rates, fresh and dry root weights as well as antioxidant enzymatic activities such as superoxide dismutase, peroxidase, and catalase was achieved with 125 ppm SNP. The α-amino acid, proline, content was highest with this treatment while the highest H2O2 (hydrogen peroxide) was in the controls. This study introduces a cost-effective, prolific, and efficient in vitro multiplication system to supply pharmaceutical and ornamental needs. It is the first report of an in vitro organogenesis protocol for F. religiosa by direct regeneration through axenic seedling-derived petiole and leaf explants, which can be efficiently employed for the utilization of active biomolecules. 相似文献
98.
Vahid Nasiri Ali.A.Darvishsefat Reza Rafiee Anoushirvan Shirvany Mohammad Avatefi Hemat 《林业研究》2019,(3):943-957
Temporal land use/land cover (LULC) change information provides a variety of applications for informed management of land resources. The aim of this study was to detect and predict LULC changes in the Arasbaran region using an integrated Multi-Layer Perceptron Neural Network and Markov Chain analysis. At the first step, multi-temporal Landsat images (1990, 2002 and 2014) were processed using ancillary data and were classified into seven LULC categories of high density forest, low-density forest, agriculture, grassland, barren land, water and urban area. Next, LULC changes were detected for three time profiles, 1990–2002, 2002–2014 and 1990–2014. A 2014 LULC map of the study area was further simulated (for model performance evaluation) applying 1990 and 2002 map layers. In addition, a collection of spatial variables was also used for modeling LULC change processes as driving forces. The actual and simulated 2014 LULC change maps were cross-tabulated and compared to ensure model simulation success and the results indicated an overall accuracy and kappa coefficient of 97.79% and 0.992, respectively. Having the model properly validated, LULC change was predicted up to the year 2025. The results demonstrated that 992 and 1592 ha of high and lowdensity forests were degraded during 1990–2014,respectively, while 422 ha were added to the extent of residential areas with a growth rate of 17.58 ha per year. The developed model predicted a considerable degradation trend for the forest categories through 2025, accounting for 489 and 531 ha of loss for high and low-density forests, respectively. By way of contrast, residential area and farmland categories will increase up to 211 and 427 ha, respectively. The integrated prediction model and customary area data can be used for practical management efforts by simulating vegetation dynamics and future LULC change trajectories. 相似文献
99.
Phenolic glycosides from Dodecadenia grandiflora and their glucose-6-phosphatase inhibitory activity
Manmeet Kumar Preeti Rawat Mohammad Faheem Khan Akhilesh K. Tamarkar Arvind K. Srivastava Kamal R. Arya Rakesh Maurya 《Fitoterapia》2010
Phytochemical investigation of Dodecadenia grandiflora leaves led to the isolation and identification of three phenolic glycosides, designated 1-[(4′-O-(E)-p-coumaroyl)-β-d-glucopyranosyl]-oxy-2-phenol (1), 1-[(6′-O-(E)-p-coumaroyl)-β-d-glucopyranosyl]-oxy-2-phenol (2) and 1-[O-β-d-glucopyranosyl(1→2)-β-d-glucopyranosyl]-oxy-2-phenol (3), along with nine known compounds. Compounds 1, 2, 5 and 9 exhibited significant glucose-6-phosphatase inhibitory activity (63.7, 66.9, 82.9 and 85.4%) with IC50 values of 88.5, 81.0, 51 and 50 μM respectively. On the basis of biological results, a structure–activity relationship has been discussed. 相似文献
100.
This paper explores the influence over time of past policies on people’s attitudes towards the use of forestland in Bangladesh.
The discourses of the attitudes of people were captured from the observed social tradition towards forest resources. Forests
were reserved systematically and solely through the Forest Department. The conservation processes were not participatory,
and rights and tenure were strictly controlled. People were socially excluded and alienated from the forest, and the socio-political
factors stimulated negative attitudes among people. Forests were considered to be government property, and therefore managing
forests was the responsibility of the government. People only used forest resources to meet their own requirements, either
with formal permission or illegally. This situation continued even after the independence of Bangladesh in 1971. As a result,
the forests of Bangladesh have been degraded heavily in recent decades. 相似文献