A study on the micro-environment, litter accumulation on forest floor and available nutrients in the soils of broadleaved, mixed pine and pine forests at two distinct altitudes in Meghalaya, North East India

作者：Mishra B P^*

来源：Current Science, 2010, 99(12): 1829-1833.

• Available nutrients
• litter accumulation
• micro-environment
• Northeast India
• nutrient status

The present study deals with the micro-environment, litter accumulation and status of available nutrients in the major forest types (broadleaved, mixed pine and pine forests) at two distinct altitudes in Meghalaya, North East India. The representative forest stands were selected at two markedly distinct altitudes at Umroi (ranging from 1100 to 1200 m asl) and Upper Shillong (ranging from 1900 to 2000 m asl). The findings depict that the temperature (ambient and soil) was markedly high at Umroi, and greater values were recorded during pre-monsoon season in all the cases. Relative humidity was high in Upper Shillong, and values decreased from broadleaved to pine forest at both altitudes. Light interception was decreased from broadleaved to pine forest and higher values were recorded in the representative forests at Upper Shillong. Litter accumulation on the forest floor decreased from broadleaved to pine forest, and higher values were obtained at Upper Shillong, with a maximum in the broadleaved forest during pre-monsoon season. Soil moisture was higher in the topsoil than sub-soil, and values decreased from broadleaved to pine forest. The forest stands at Upper Shillong showed markedly high values and lower values were recorded during pre-monsoon season. Soil pH was acidic in nature. Organic carbon, total Kjeldahl nitrogen and available phosphorus were high in the topsoil, with some exceptions in the case of available phosphorus due to leaching, irrespective of seasonal variation. The concentration of these nutrients decreased from broadleaved to pine forest and higher values were obtained for post-monsoon season in the respective forest type. Peak values were recorded at Upper Shillong during post-monsoon season. From the findings it has been concluded that forest-floor characteristics, micro-environment and nutrients status are highly linked with the nature of vegetation and altitude. It was also observed that polyculture helped soil fertility in terms of available nutrients. The results on C: N ratio depict that pine forests (monoculture) at both the altitudes are nutrient-poor.

• 出版日期2010-12-25