After subjecting the seeds to GA3 and H2O2 treatments for 24 h and chilling at 2-3℃ for a period of 15 days, we conducted the seed germination tests for 21 different seed sources ofPinns roxburghii from western-centr...After subjecting the seeds to GA3 and H2O2 treatments for 24 h and chilling at 2-3℃ for a period of 15 days, we conducted the seed germination tests for 21 different seed sources ofPinns roxburghii from western-central Himalaya under laboratory conditions at various temperatures viz., 20℃, 25℃ and 30℃ inside a seed germinator. The results reveal that the soaking of seeds in H2O2 （1% v/v） and GA3 （ 10 mg.L^-1） solutions manifested 82.39% and 78.19% germination, respectively whereas untreated seeds exhibited 70.79% average germination. Both GA3 and H2O2 treatments caused an appreciable shortening of the germination period by 8 days and 10 days, respectively. Moist-chilling did improve the rate and percentage of germination when germinated at 20℃ over 21 days; however total germination was not affected at temperatures 25℃ and 30℃, Although the seeds of P. roxburghii germinate well due to lack of dor- mancy, the increasing demand for large quantities of seeds of P. roxburghii for reforestation programmes make pre-sowing treatments useful in improving the rate and percentage of gemaination.展开更多
We investigated whether species richness, diversity and density of understory herbaceous plants differed along logging(gap) and grazing(primarily by cattle) disturbance gradients, and sought to identify drivers of ric...We investigated whether species richness, diversity and density of understory herbaceous plants differed along logging(gap) and grazing(primarily by cattle) disturbance gradients, and sought to identify drivers of richness, diversity and density of understory vegetation of logged sites. A factorial experiment was conducted in the mixed conifer forest of Gidakom in Western Bhutan. Levels of the logging treatment included small(0.15 – 0.24 ha), medium(0.25 – 0.35 ha) and large(0.36 – 1.31 ha) gaps. The grazing treatment included grazed(primarily by cattle) and ungrazed(where herbivores were excluded by a fence) plots nested within each gap. Data were collected from 12 gaps(4 replicates at each level of logging) using the point intercept method. Shannon Weaver Diversity and Margalef's indices were used to estimate species diversity and describe species richness, respectively. Soil samples were analyzed for pH and nutrients. The interaction effect of logging and grazing was significant(p≤0.001) only on species diversity. Relative to ungrazed areas, species diversity was significantly higher(0.01≤p≤0.05) in medium grazed gaps. Under grazed conditions, soil P was negatively correlated with gap size and species diversity. While species diversity was positivelycorrelated(0.01≤p≤0.05) with soil N in grazed plots species richness was positively correlated(0.001≤p≤0.01) with soil N in ungrazed plots. Relative density of Yushania microphylla and Carex nubigena were higher under ungrazed conditions. Our study suggests that the combined effect of cattle grazing and logging results in higher species diversity of understory vegetation in medium and grazed gaps in mixed conifer forests of Bhutan,whereas increase or decrease in relative density of major species is determined primarily by the independent effects of grazing and logging. From management perspective, forest managers must refrain from creating large gaps to avoid loss of nutrients(mainly P and N), which may eventually affect tree regeneration. Managers intending to maintain understory vegetation diversity must consider the combined effects of grazing and logging, ensuring low to moderate grazing pressure.展开更多
To a monotypic genus Himindica Saini from India, three new species are added a fresh. Described and illustrated as new are: H. nigrithorax, H. maculipleuris and H. meghalayaensis. A key for identification of all four...To a monotypic genus Himindica Saini from India, three new species are added a fresh. Described and illustrated as new are: H. nigrithorax, H. maculipleuris and H. meghalayaensis. A key for identification of all four species is provided.展开更多
The present study deals with the regeneration status of a sub- tropical forest located between 950-1100 m above sea level in Garhwal Himalaya. The vegetation was quantitatively analyzed on four different aspects i.e.,...The present study deals with the regeneration status of a sub- tropical forest located between 950-1100 m above sea level in Garhwal Himalaya. The vegetation was quantitatively analyzed on four different aspects i.e., east, west, north and south. Results of the study indicated that across the aspects, Anogeissus latifolia was dominant in tree, sapling and seedling layers in all the aspects, except north aspect where Pinus roxburghii and Terminalia tomentosa were dominant in tree and seedling layers, respectively. The highest tree layer density （380 plant.ha^-1） was recorded on south aspect and lowest （260 plant.ha^-1） on west aspect. In shrub layer, highest density was on east aspect （1790 plant.ha-1） and lowest on west aspect （970 plant.hal）. Tree and shrub layer diversity ranged between 0.846 to 1.710 and 1.943 to 2.847, respectively. The relative lopping intensity （%） was higher in Anogeissus latifolia （45%- 57% as compared to 4%-33% in other species） which is the most important tree species on all aspects, except north aspect. The present study also reveals that if the current rate of exploitation continues, the species like Anogeissus latifolia may be replaced by other species and drastic changes may occur in species composition and regeneration of the forest. The anthropogenic pressure, aspect and soil nutrients have caused changes in regeneration status and species composition of forests.展开更多
Habitat utilization and feeding biology of Himalayan Grey Langur （Semnopithecus entellus ajex） were studied from April, 2006 to April, 2007 in Machiara National Park, Azad Jammu and Kashmir, Pakistan. The results sh...Habitat utilization and feeding biology of Himalayan Grey Langur （Semnopithecus entellus ajex） were studied from April, 2006 to April, 2007 in Machiara National Park, Azad Jammu and Kashmir, Pakistan. The results showed that in the winter season the most preferred habitat of the langurs was the moist temperate coniferous forests interspersed with deciduous trees, while in the summer season they preferred to migrate into the subalpine scrub forests at higher altitudes. Langurs were folivorous in feeding habit, recorded as consuming more than 49 plant species （27 in summer and 22 in winter） in the study area. The mature leaves （36.12%） were preferred over the young leaves （27.27%） while other food components comprised of fruits （17.00%）, roots （9.45%）, barks （6.69%）, flowers （2.19%） and stems （1.28%） of various plant species.展开更多
基金suportted by the Indian Council of Forestry Research and Education (ICFRE) Dehradun
文摘After subjecting the seeds to GA3 and H2O2 treatments for 24 h and chilling at 2-3℃ for a period of 15 days, we conducted the seed germination tests for 21 different seed sources ofPinns roxburghii from western-central Himalaya under laboratory conditions at various temperatures viz., 20℃, 25℃ and 30℃ inside a seed germinator. The results reveal that the soaking of seeds in H2O2 （1% v/v） and GA3 （ 10 mg.L^-1） solutions manifested 82.39% and 78.19% germination, respectively whereas untreated seeds exhibited 70.79% average germination. Both GA3 and H2O2 treatments caused an appreciable shortening of the germination period by 8 days and 10 days, respectively. Moist-chilling did improve the rate and percentage of germination when germinated at 20℃ over 21 days; however total germination was not affected at temperatures 25℃ and 30℃, Although the seeds of P. roxburghii germinate well due to lack of dor- mancy, the increasing demand for large quantities of seeds of P. roxburghii for reforestation programmes make pre-sowing treatments useful in improving the rate and percentage of gemaination.
基金support of the Government of Austria with funds routed through the sterreischer Austauschdienst(OeAD)
文摘We investigated whether species richness, diversity and density of understory herbaceous plants differed along logging(gap) and grazing(primarily by cattle) disturbance gradients, and sought to identify drivers of richness, diversity and density of understory vegetation of logged sites. A factorial experiment was conducted in the mixed conifer forest of Gidakom in Western Bhutan. Levels of the logging treatment included small(0.15 – 0.24 ha), medium(0.25 – 0.35 ha) and large(0.36 – 1.31 ha) gaps. The grazing treatment included grazed(primarily by cattle) and ungrazed(where herbivores were excluded by a fence) plots nested within each gap. Data were collected from 12 gaps(4 replicates at each level of logging) using the point intercept method. Shannon Weaver Diversity and Margalef's indices were used to estimate species diversity and describe species richness, respectively. Soil samples were analyzed for pH and nutrients. The interaction effect of logging and grazing was significant(p≤0.001) only on species diversity. Relative to ungrazed areas, species diversity was significantly higher(0.01≤p≤0.05) in medium grazed gaps. Under grazed conditions, soil P was negatively correlated with gap size and species diversity. While species diversity was positivelycorrelated(0.01≤p≤0.05) with soil N in grazed plots species richness was positively correlated(0.001≤p≤0.01) with soil N in ungrazed plots. Relative density of Yushania microphylla and Carex nubigena were higher under ungrazed conditions. Our study suggests that the combined effect of cattle grazing and logging results in higher species diversity of understory vegetation in medium and grazed gaps in mixed conifer forests of Bhutan,whereas increase or decrease in relative density of major species is determined primarily by the independent effects of grazing and logging. From management perspective, forest managers must refrain from creating large gaps to avoid loss of nutrients(mainly P and N), which may eventually affect tree regeneration. Managers intending to maintain understory vegetation diversity must consider the combined effects of grazing and logging, ensuring low to moderate grazing pressure.
文摘To a monotypic genus Himindica Saini from India, three new species are added a fresh. Described and illustrated as new are: H. nigrithorax, H. maculipleuris and H. meghalayaensis. A key for identification of all four species is provided.
文摘The present study deals with the regeneration status of a sub- tropical forest located between 950-1100 m above sea level in Garhwal Himalaya. The vegetation was quantitatively analyzed on four different aspects i.e., east, west, north and south. Results of the study indicated that across the aspects, Anogeissus latifolia was dominant in tree, sapling and seedling layers in all the aspects, except north aspect where Pinus roxburghii and Terminalia tomentosa were dominant in tree and seedling layers, respectively. The highest tree layer density （380 plant.ha^-1） was recorded on south aspect and lowest （260 plant.ha^-1） on west aspect. In shrub layer, highest density was on east aspect （1790 plant.ha-1） and lowest on west aspect （970 plant.hal）. Tree and shrub layer diversity ranged between 0.846 to 1.710 and 1.943 to 2.847, respectively. The relative lopping intensity （%） was higher in Anogeissus latifolia （45%- 57% as compared to 4%-33% in other species） which is the most important tree species on all aspects, except north aspect. The present study also reveals that if the current rate of exploitation continues, the species like Anogeissus latifolia may be replaced by other species and drastic changes may occur in species composition and regeneration of the forest. The anthropogenic pressure, aspect and soil nutrients have caused changes in regeneration status and species composition of forests.
文摘Habitat utilization and feeding biology of Himalayan Grey Langur （Semnopithecus entellus ajex） were studied from April, 2006 to April, 2007 in Machiara National Park, Azad Jammu and Kashmir, Pakistan. The results showed that in the winter season the most preferred habitat of the langurs was the moist temperate coniferous forests interspersed with deciduous trees, while in the summer season they preferred to migrate into the subalpine scrub forests at higher altitudes. Langurs were folivorous in feeding habit, recorded as consuming more than 49 plant species （27 in summer and 22 in winter） in the study area. The mature leaves （36.12%） were preferred over the young leaves （27.27%） while other food components comprised of fruits （17.00%）, roots （9.45%）, barks （6.69%）, flowers （2.19%） and stems （1.28%） of various plant species.
