{'fraction_non_alphanumeric': 0.030303030303030304, 'fraction_numerical': 0.020202020202020204, 'mean_word_length': 4.803347280334728, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 4, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Seasonal variation in heavy metals of forest soils of Dehradun

The present study was carried out to characterise the load of heavy metal in the forest soils of Dehradun during various seasons. Surface (0-15 cm) and sub surface (15-30 cm) soil samples were collected from four different sites during summer, monsoon and winter seasons. The results revealed that the maximum Cadmium concentration was recorded in surface (0-15cm) soils and minimum in sub-surface soils (15-30cm). The Cd concentration maximum during summer followed by winter and monsoon. Similar pattern of distribution of chromium was recorded in surface soil. The Chromium content was observed in the order of winter>summer>monsoon in surface soil and summer>winter>monsoon in sub-surface soils. The concentration of Copper in surface soils varied from 3.19 to 0.52mgkg-1 while in sub-surface soil, it varied between 2.25 and 0.57 mg kg-1. The copper concentration was maximum during winter followed by summer and monsoon. The lead concentration was recoeded maximum at site-II and minimum at site-IV whereas, it was recorded maximum during winter and minimum during monsoon. In general, all the heavy metals were found to decrease with soil depth. The concentrations of heavy metal were quite low but their presence in sites makes them potential to increase toxicity in future owing to more environmental degradation.