The level of soil organic carbon (SOC) fluctuates in different types of forest stands: this variation can be attributed to differences in tree species, and the variables associated with soil, climate, and topographical features. The present review evaluates the level of SOC in different types of forest stands to determine the factors responsible for the observed variation. Mixed stands have the highest amount of SOC, while coniferous (both deciduous-coniferous and evergreen-coniferous) stands have greater SOC concentrations than deciduous (broadleaved) and evergreen (broadleaved) tree stands. There was a significant negative correlation between SOC and mean annual temperature (MAT) and sand composition, in all types of forest stands. In contrast, the silt fraction has a positive correlation with SOC, in all types of tree stands. Variation in SOC under different types of forest stands in different landscapes can be due to differences in MAT, and the sand and silt fraction of soil apart from the type of forests.

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The Northeastern hilly states of India harbor nearly 90 species of bamboos, 41 of which are endemic to the region. Estimation of C-storage and C-sequestration in aboveground biomass of two common bamboo species namely Bambusa tulda and Dendrocalamus longispathus was carried out in Mizoram-one of the eight states of Northeastern India. Recording of density of culms was done by quadrate method and harvesting of culms was done to estimate the aboveground biomass. C-storage in different components of the culms was found out for three age classes namely 1, 2 and ≥ 3 year old culms. Aboveground biomass ranged from 73.58 to 127 Mg/ha in Bambusa tulda and 115 to 150 Mg/ha in Dendrocalamus longispathus. Culm density and aboveground biomass were maximum in the ≥ 3 year age class in both the species. C-storage ranged from 36.34 to 64.00 Mg/ha in Bambusa tulda and 50.11 to 65.16 Mg/ha in Dendrocalamus longispathus. Although having lower aboveground biomass the rate of C-sequestration was higher in Bambusa tulda with 27.79 Mg/ha/year than Dendrocalamus longispathus which have 15.36 Mg/ha/year. The reason was attributed to higher increment of culm density and DBH of the older age class in the second year study period in Bambusa tulda.

In the present study four different types of organic solid wastes namely: sugarcane waste, fish waste, flower waste and pineapple waste were selected and amended in soil. Plantation of saplings of Solanum melongena were done in the amended soil and changes in the growth pattern, biomass and soil characteristics were observed by comparing with unamended pots. It was observed that amendment of flower waste leads to an overall increase in the productivity of crop. On an average there was an increase of 11.7cm in height, 13 number of leaves, 5cm in root length and 3.4 g of biomass in the flower waste amended pots. Sugarcane and fish wastes amendment did not show positive impact on the crop. Pineapple wastes showed positive change. Soil moisture, organic C and N increased in all types of amendments. Available K increased only in flower and pineapple wastes amendment. There was significant correlation between crop and soil characteristics showing faster release of K in flower waste led to an increase in production of the crop.

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Maize is a highly consumed staple food in developing countries and the demand is predicted to double in the coming years. Therefore, there is a need to improve production through the use of compost amendments for sustainability. The aim of this study was to examine the effect of three compost amendments (lemon peels, vegetable waste, and cooked food waste) on the germination and growth of maize (Zea mays). The results showed that the application of 17% (116 t/ha) of vegetable waste or lemon peel composts supported maximum maize growth. However, vegetable waste compost had the highest potassium content, which supported maximum root growth and biomass yield. Although the addition of 17% cooked food waste compost resulted in excess nitrogen supply, reducing its application to 7% (50t/ha) supplied the required level for maize germination.

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Composting is the most viable treatment for biodegradable solid waste. Numerous techniques have been developed by different agencies to carry out composting. The most common method is aerobic bin method carried out on small scale. Compost piles and windrow methods needs larger land area and are mainly carried out by industries. The total time for completion of composting depend upon the type of substrate and the methods employed. Moisture content, temperature, pH and C:N ratio are among the most important factors for carrying out composting. The present review emphasised on the estimation of time taken by different types of substrates under different methods of composting and the changes in temperature, pH and C:N ratio occurring therein.