Carbon Sequestration Potential of Agricultural Crops in Designed Plant Growth Chamber.

Aim: Climate change is becoming one of the major global environment concerns. The earth’s climate is predicted to change due to release of greenhouse gases and there is an urgent need for stabilizing the increasing levels of carbon dioxide in atmosphere. Soil carbon sequestration is considered as one of the promising options for mitigating the climate change impacts. The aim of the current study is to assess the carbon sequestration potential of the crops of the agricultural importance at elevated levels of CO2 in designed plant growth chamber. Place and Duration of Study: School of Environment and Sustainable Development, Central University of Gujarat, India, between November 2013 to June 2014. Methodology: Plant growth chamber has been designed of dimension 66×24×25 inches for assessing the carbon sequestration potential of the selected agricultural crops Triticum aestivum, Sorghum vulgare and Vigna radiata in green house. The plants were grown using the pot culture technique in mycorrhizal soil. The CO2 was induced into the plant growth chamber after every five days at the rate of 5 Litres per minute to maintain the level of carbon dioxide upto 500±50 ppm into the plant growth chamber and plant’s growth was studied. Soil’s physico-chemical parameters, plant’s morphological and biochemical characteristics were studied in each plant. Results: The study reveals the carbon content estimated in the form of organic carbon, total carbon and organic matter was high in Vigna radiata at elevated CO2 levels, than ambient levels, followed by Sorghum vulagare and Triticum aestivum. Also organic nitrogen accumulation was increased in response of elevated CO2 conditions, highest being found in samples of Vigna radiata. Morphological and biochemical characteristics of crops also got influenced under elevated CO2 levels. Plant height and plant biomass accumulation was found to be higher in Triticum aestivum, followed by Sorghum vulgare and Vigna radiata, whereas shoot and root length was measured to be highest in Sorghum vulgare, then in Vigna radiata and Triticum aestivum. Biochemical analysis revealed that total chlorophyll content was highest in Sorghum vulgare as compared to other two species at elevated conditions. Protein content increased in response to elevated CO2 conditions, it was found to be highest in Triticum aestivum. Conclusion: It can be inferred from this study that CO2 has influence on both soil’s and properties of plant’s growing in it. It was observed that C3 crops Triticum aestivum and Vigna radiata were more efficient in using the elevated carbon dioxide levels and hence will prove useful in mitigating the impacts of climate change with the help of sequestration of carbon both in plant and soil. Sorghum vulgare being a C4 also showed potential for carbon sequestration and can be considered for the same after further more research.

Riparian forest potential to retain sediment and carbon evaluated by the 137Cs fallout and carbon isotopic ratio techniques

Riparian forests can provide an important service for aquatic ecosystems by sequestering hillslopederived sediments. However, the width of a riparian buffer zone required to filter sediments is not yet wellunderstood. Here are used two complementary tracers to measure sediment retention. The 137Cs technique and the soil carbon isotopic ratios (δ13C) are utilized to investigate sediment deposition and erosion rates on a slope transect cultivated with sugarcane followed by a secondary riparian forest zone in Iracemápolis, State of São Paulo, Brazil. The 137Cs technique and the δ13C analysis showed that the width of a riparian vegetation in accordance to a Brazilian Environmental Law (Nº4.771/65) was not sufficient in trapping sediments coming from agricultural lands, but indicated the importance of these forests as a conservation measure at the watershed scale. The complementary δ13C analysis together with soil morphology aspects allowed a better interpretation of the sediment redistribution along the sugarcane and riparian forest transects.

As matas ciliares podem fornecer serviços importantes para os ecossistemas aquáticos sequestrando sedimentos oriundos das áreas de encostas. No entanto, a largura da zona ripária necessária para a retenção de sedimentos ainda não está bem determinada. Aqui são usadas duas técnicas complementares para medir a retenção de sedimentos. As metodologias do137Cs e da composição isotópica do carbono (δ13C) são utilizadas para avaliar a deposição de sedimentos e taxas de erosão em uma encosta cultivada com cana-de-açúcar seguida poruma mata ciliar situada em Iracemápolis, no Estado de São Paulo, Brasil. As análises pelas técnicas do 137Cs e δ13C mostraram que a largura da mata ciliar definida pela Lei Ambiental Brasileira (Nº4.771/65) não foi suficiente na retenção de sedimentos oriundos de áreas cultivadas, mas indicou a importância destas florestas como medida de conservação de bacias hidrográficas. A análise complementar de δ13C junto com informações morfológicas do solo permitiu melhor interpretação da redistribuição de sedimentos ao longo das áreas de cana-de-açúcar e mata ciliar.