No abstract

No abstract

Introduction: The study was conducted in Mudumalai Tiger Reserve, in the Western Ghats to understand the effect of a single fire event on tree diversity and regeneration status. Four forest patches were selected which were unburned, 2-year-old burn, 5-year-old burn, and 15-year-old burn. Three 0.1 ha square plots were laid randomly in all four patches and analyzed for tree diversity, stand structure, and regeneration of tree species. Results: A total of 4129 individuals of tree species were recorded in field surveys, comprising 3474 seedlings, 121 saplings, and 534 trees. Totally, 40 tree species were recorded in study plots, from which 28 species were seedlings, 16 species were saplings, and 37 species were at tree stages. Conclusions: Tree diversity decreased in 2-year-old and 5-year-old burnt plots and was reached to the level of unburnt plots in 15 years of interval. Stems of small size classes started increasing after the fire. Seedling density increased linearly in subsequent years after fire but sapling and tree density recorded less than control in B2 but was higher in B5 and B15. The overall fire affected diversity, but regeneration showed a positive trend.

SummaryRemote sensing with hyper spectral sensors can provide the fine resolution required for sitespecific farming. The within-field spatial distribution of some soil properties was found by using multiple linear regressions to select the best combinations of wave bands, taken from among a full set of 512 narrow bands in the wavelength range of 350 to 1050 nm. The resulting regression equations made it possible to calculate the value of the soil property with a spatial resolution of 3.0 nm FWHM (Full Width Half Maximum). Both surface and subsurface samples of soil profile were taken from the three research stations. The soil samples were tested in a laboratory for 20 different properties. The per cent sand was found to be detectable with a reasonable degree of accuracy with R 2 = 0.851 for a three parameter model; the best combination of wavelengths was 426.81, 730.47 and 1037.7 nm. For silt, clay, field capacity, wilting point, Available water content, pH, electrical conductivity and CaCO 3 the results were ranges of degree of accuracy with R 2 from 0.609 to 826. The soil exchangeable properties such as Ca, Mg, Na and CEC, chemical composition such as SiO 2 and Fe 2 O 3 R 2 values varied from 759 to 906. The poorest fit was for organic carbon with R 2 = 0.220 followed by Al 2 O 3 (R 2 = 0.313). Available micronutrients (Fe and Mn) had R 2 0.491 and 0490. For all the properties except organic carbon and Al 2 O 3 , the correlation was statistically significant. The main findings were that some soil properties can be accurately detected using hyper spectral remote sensing.

No abstract