pinus roxburghii
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2021 ◽  
Vol 16 (3) ◽  
pp. 733-739
Author(s):  
Bhawna Tewari ◽  
Ashish Tewari

The Himalayan forests are rich in biodiversity and distributed over a large extent from lower to higher elevations. The dependence of the locals for their daily requirements of fuel, fodder and medicinal plants is high on these forests. The study was conducted at altitude varied between 1725 and 3250 masl (above sea level) in Kumaun region. The study deals with the comparison of tree layer vegetation in higher elevation sites (HES) and mid elevation sites (MES) with reference to Diversity, Richness, Basal area (BA), Dominance and Important Value Index. The MES were dominated by mixed Quercus leucotrichophora and Pinus roxburghii forests where as HES sites were dominated by Quercus semecarpifolia and Aesculus indica forests and Rhododendron campanulatum in the understory. Across all the sites the tree species richness ranged between 9 and 15. Tree density was maximum (1400 trees/ha) at MES. Tree diversity and total basal area were maximum at HES. The study will be useful in developing baseline data for carrying out future studies. The data generated will be helpful for the conservation of biodiversity of the region.


2021 ◽  
Vol 51 ◽  
Author(s):  
Ajmal Samani ◽  
Sauradipta Ganguly ◽  
Sanjeet Kumar Hom

Background: Depleting supplies of wood species with inherent natural durability has resulted in the focus being shifted to non-durable plantation grown and imported timber. Despite its abundant availability and better treatability, the use of Pinus roxburghii is limited to packing cases, crates, shutters, door and window frame, carpentry and joinery items due to its nondurable nature. Hence, to promote use of such timber for applications such as decking, cladding and facade elements chemical modification with a combination of citric acid and sodium hypophosphite, and heat treatment were explored to improve its service life. Methods: Chemical modification was performed using a water solution of citric acid (6.9%) and sodium hypophosphite (6.5%) followed by curing at 140°C for 8 hrs. Dimensional stability was determined by estimating the volumetric swelling coefficient and anti-swelling efficiency (ASE) of treated and control samples. Durability against fungus and termites was evaluated using a soil block bioassay and termite mound test as per standard methods. Results: Both chemical modification and heat treatment of P. roxburghii resulted in enhanced dimensional stability and biological durability compared to the untreated controls. Chemical modification and heat treatment resulted in 23.05% and 18.37% volumetric ASE, respectively. Results showed that a highly perishable species became significantly more durable after chemical modification, exhibiting 5–6 times less mass loss by termites in comparison to the controls. Wood samples modified with citric acid showed excellent resistance to both white and brown rot fungi and exhibited 14-15 times less reduction in mass compared with untreated samples. Conclusions: Citric acid chemical modification is an environment friendly process that improved the dimensional stability as well as resistance against biodegradation. These studies may provide valuable inputs to establish this mode of chemical modification as a cost-effective alternative to other chemicals for wood preservation. The concentrations of the chemicals and temperature for fixation may be varied to establish an optimum combination for best output.


2021 ◽  
Vol 42 ◽  
pp. 27-40
Author(s):  
Muhammad Daud Khan ◽  
Saba Ali Arooj ◽  
Waqar Ahmed ◽  
Zia-ur Rehman ◽  
Arif Iqbal ◽  
...  

In context of Bonn Challenge commitment, Pakistan (Khyber Pukhtunkhwa) has implemented forest restoration and afforestation on 0.35 million hectares between 2015–2017. Billion Tree Afforestation Project (BTAP) is an initiative of mass afforestation and forest restoration to meet the Bonn Challenge commitment. The current study is a pilot study to evaluate the success of plantation activities by assessment of regeneration, growth performance and survival rate of plantations raised under BTAP in Malakand Forest Division. Further, four vegetation indices were computed from Landsat-8 image, which include Normalized Difference Vegetation Index (NDVI), Soil Adjusted Vegetation Index (SAVI), Modified Soil Adjusted Vegetation Index (MSAVI) and Difference Vegetation Index (DVI). A total of 72 sample plots of 0.1 ha were laid out in 11 plantation sites extended over an area of 647 ha in Timargara, Chakdara and Jandool. According to the results, all the selected plantation sites showed good performance in terms of survival rate, mostly above 90%. In terms of species composition, Eucalyptus camaldulensis has the highest share (81%) followed by Robinia pseduacacia with 17% and Pinus roxburghii with 2% share in the plantation. Growth performance was good in all species; Pinus roxburghii attained an average girth of 14.3 cm and height of 3.21 feet, whereas Eucalyptus camaldulensis and Robinia pseudoacacia attained a mean girth of 10.3 and 12.1 cm with the height of 8.6 and 8.2 feet in 27 months, respectively. Further, a good correlation was observed between the volume (m3) and Landsat-8 spectral values. The highest performance (R2=0.63) was recorded by NDVI and SAVI. The temporal changes in spectral values of Landsat-8 images from 2013 to 2018 showed that the plantation was successful at these sites. The study concluded that FLR activities across the Khyber Pukhtunkwa province will rehabilitate and improve the existing forest ecosystems and support local livelihood for climate change mitigation.


2021 ◽  
Vol 22 (3) ◽  
pp. 423-431
Author(s):  
Sanjay Sharma ◽  
Dalip Kumar

The present study was conducted in Kalidhar forest of western Shiwaliks, Jammu, JK (UT), to assess the tree diversity and undertake phytosociological analysis in three major land use (LU) classes i.e. Forest, Agriculture and Scrub area.  A total of 70, 50 and 50 sample plots of 0.1 ha were laid respectively in forests, scrub and agriculture LU classes. The study revealed that in forests possess a total 39 tree species belonging to 19 families and 31 genera, whereas, in scrub and agriculture lands a total of 9 tree species (8 families and 9 genera) and 60 tree species (26 families and 46 genera) were recorded respectively. Mallotus philippensis was the most dense tree species with 2.85 individuals per ha in forests followed by Pinus roxburghii 2.06 per hectare.  In scrub and agriculture land Acacia modesta and Grewia optiva were found the densest species respectively. The value of Importance value index (IVI) was found highest for Pinus roxburhii (44.63) in forests, whereas, respective values were recorded highest for Syzygium cumini (82.64) and Grewia optiva (29.0) in scrub and agriculture lands. Flacourtia indica and Pinus roxburghii showed random distribution in forest and Syzygium cumini was also found to have random distribution in the scrub lands. Contiguous distribution was found for all tree species encountered in agriculture (LU) class. The diversity values of Shannon Wiener and Simpson indices showed highest tree diversity in agriculture lands with the values of 3.19 and 0.07 respectively followed by that in forests (2.47 and 0.14). Tree species richness was found high in agriculture area with Margalef’s (59.86) and Menhinick’s (1.80).


2021 ◽  
pp. 149-153
Author(s):  
Leishangthem Chanu Langlentombi ◽  
Manoj Kumar

Prediction of the potential geographic distribution of species is essential concerning various purposes in protection and conservation. The present study focused on predicting the distribution of Pinus roxburghii Sarg. (chir pine) in Uttarakhand Himalayas using the MaxEnt model. The model produced AUC curve with significant value of 0.882 (± 0.023). The study results showed that 426200 ha (5.91%) cover highly potential habitat area for chir pine. Whereas 833900 ha (11.56%), 1019200 ha (14.13%) and 4936000 ha (68.41%) cover good potential, moderately potential and least potential habitat areas, respectively. Based on the jacknife test, it was observed that temperature seasonality (bio4), precipitation of seasonality (bio15) and precipitation of driest month (bio14) are the significant contributors to the occurrence of chir pine in Uttarakhand Himalayas. This study exemplifies the usefulness of the prediction model of species distribution and offers a more effective way to manage chir pine forest by all means, which is beneficial for both the wildlife and human beings for future prospects.


2021 ◽  
Vol 21 (2) ◽  
Author(s):  
B.S. Bhandari ◽  
Toseef Riaz ◽  
R.S. Rawat

Oak (Quercus oblongata) is an important component of mid-altitude ecosystem of the Central Himalaya which are exposed to over-exploitation making conditions favourable for the invasion by light-demanding conifers such as chirpine (Pinus roxburghii). The present study provides information on woody vegetation structure, composition, regeneration and management of four broadleaved forest stands of Garhwal Himalaya managed by Village Panchayat. Quercus oblongata was the most important and dominant species in all the stands. Although dominance was shared by a number of species, no single species was found to complete with this climax species. The presence of Alnus nepalensis (a nitrogen-fixing species) depicts the poor nitrogen status of these forest stands. High density values and low basal cover suggest that these community forest stands are younger than the natural oak reserve forests of the Central Himalaya. The richness index shows that the seedling strata are ecologically richer than the tree, sapling and/or shrub strata. High richness in the seedling strata is attributed to the low magnitude of biotic interferences in these communities based conserved forest stands. The regeneration potential of Quercus oblongata is much higher than the natural oak forests of Central Himalaya managed by the forest department. This supports the view that moderate disturbance regimes are more conducive to satisfactory regeneration of this species. Since the management of these forest stands is looked after by the Village Panchayat, they are introducing some conifers for their vested interests. This may add an additional competition of the broadleaved climax species with conifers as has been witnessed in most of the broadleaved oak forests of this altitudinal range.


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