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Environmental Fluid Mechanics - Pedestrian level wind comfort, natural ventilation and pollutant dispersion are strongly influenced by building shape and orientation. In the recent years, the trend... 相似文献
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Chemical properties of soils in relation to forest composition in moist temperate valley slopes of Garhwal Himalaya, India 总被引:1,自引:0,他引:1
The present study was undertaken in moist temperate forest of Mandal-Chopta area in the Garhwal region of Uttarakhand, India. The aim of the present study was to assess the chemical properties of soils in relation to the forest structure and composition. Twelve forest types according to the altitude, slope aspect, and species composition were selected for the study. Chemical properties of the soil, i.e., total nitrogen (N), available phosphorus (P), available potassium (K), organic carbon (C), soil organic matter (SOM), pH and C:N ratios were analyzed for three different depths viz., (i) ??Upper?? (0?C10?cm), (ii) ??Middle?? (11?C30?cm), and (iii) ??Lower?? (31?C60?cm) in all the selected forest types. Phytosociological and diversity parameters viz. total basal cover (Gha?1), stem density (Nha?1), tree species richness (SR), Simpson concentration of dominance and Shannon?CWiener diversity index ( $ \overline{\rm H} $ ) were also calculated for each forest type. Values of N, P, K, C, SOM, C:N ratio and pH ranged from 0.17 to 0.45?%, 2.73 to 20.17?ppm, 40.67 to 261.17?ppm, 2.29 to 4.31?%, 3.95 to 7.43?%, 8.12 to 14.49 and 5.47 to 6.67, respectively. N showed a positive relationship with C and K. P was positively correlated with C and negatively correlated with altitude. P was higher in the soil of lower horizons of all the forest types. K was found to be positively correlated with altitude, C and N. pH of all the forest types was slightly acidic. C was comparatively higher in mixed broad-leaved forest types. No relationship between altitude and C was observed, which may be due to different composition of forest types along the altitudinal gradient and their differential decomposition rates. C content decreased with the depth of the soil. C showed positive correlation with N, P, and K. N showed a positive correlation with Gha?1. K showed a negative correlation with SR and $ \overline{\rm H} $ . P showed no relationship with the phytosociological parameters. This study also provides the comparisons between the results of chemical analysis of the present study with numerous other previous studies in the temperate Himalayan region of the Uttarakhand. The values of soil chemical properties of the present study in most of the forest types are on the higher end than the values previously recorded for the other similar forests of the region. The possible reason being luxuriant vegetation and undisturbed nature of these forest types, which is evident from higher values of diversity and other phytosociological parameters. 相似文献
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We have made an attempt to understand the significance of physiographic factors viz., altitude, aspect, slope and soil characteristics
in determining the structure, composition, growth behavior and distribution of Himalayan Silver Fir (Abies pindrow Spach.) through a comparative analysis of two temperate forests. The occurrence of highest density (370 and 225 ind/ha),
importance value index (213.10 and 190.60) and total basal cover (TBC; 95.72 and 51.15 m2/ha) values along with the availability of higher organic carbon (6.53 and 4.47%), nitrogen (N; 0.73 and 0.44%) and potassium
(K; 621 and 319 ppm) contents in the soils just beneath the hilltops (2,650–2,800 and 2,550–2,650 m asl), on steeper slopes
(45°–50° and 42°–45°) and North-East aspects have revealed better growth of A. pindrow on both the sites. Stem density positively correlated with TBC (0.771), Shannon–Wiener diversity index (H′; 0.879), OC (0.601),
N (0.758) and K (0.752), whereas TBC has shown significant positive relationship with H′ (0.894), K (0.793) and N (0.716).
Similarly, H′ has also shown significant positive correlation with slope (0.721), K (0.855) and N (0.791). Interestingly,
positive correlation of altitude with stem density (0.557) and of slope with TBC (0.608) was noticed in the distribution of
A. pindrow individuals. 相似文献
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Gairola Sandeep Naik Tejas Pramod Sinha Shishir Singh Inderdeep 《Journal of Material Cycles and Waste Management》2023,25(4):2063-2076
Journal of Material Cycles and Waste Management - There is an overwhelming interest in composite materials derived from bio-based waste resources, recycled plastic materials and their combinations.... 相似文献
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