A review on biomass estimation methods using synthetic aperture radar data
Author(s)– Nafiseh Ghasemi et.al.,
Due to the important role of forests in the global carbon cycle, it’s necessary to pay more attention to these regions. Among forests biophysical parameters, Biomass estimation as the most influencing factor on the ecosystem is the most important. Due to limitations of traditional forest inventory technique to measure biomass, remote sensing has been widely used for biomass estimation in the past decade. In areas with complex structure, various species and multilayer vegetation cover, using microwave images would be the only solution because of the limitation of optical images. According to recent studies about biomass estimation with microwave images, the interferometry technique yields the best results but still is limited and not tested in all forest types. Because using microwave images has its own problems, focusing on the development of the new approaches which can handle multi source data, identify and decrease uncertainty sources in biomass estimation is required in future studies.
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Utilization and treatment of dairy effluent through biogas generation- A case Study
Author(s)- Bhumesh Singh Bhadouria, Sai.V.S
Biogas is an alternate source of energy and after realizing the potential of biogas, a National level programme was initiated in India during 1970s. Present study on biogas generation from dairy effluent and control of water pollution has been viewed with the aim of control of water pollution through treatment of dairy waste as well as generation of biogas. Environmental parameters like Temperature, pH, Biological Oxygen Demand (BOD) & Chemical Oxygen Demand (COD) was taken in to account. No change in the average value of temperature and pH was recorded but BOD and COD reduced to the extent of 50 percent. All parameters however showed statistically significant differences at 5 percent level between inlet and outlet point. Gas generation fluctuated between .5m3/day to maximum 4.5 m3/day with an average of 3m3/day was recorded.
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Conversion Confusion — Does Annual P/B Equal Cohort P/B for Multi-yeared Organisms? A Cautionary Tale for Ecotoxicology Studies
Author(s)- France, R.L.
The ratio of secondary production to biomass (P/B), often referred to as the turnover rate and expressed on both a yearly and lifespan basis for aquatic macroinvertebrates and insects, has been championed as a measure of ecosystem function and as a means in which to gauge environmental disturbance. A review of the literature indicates, however, that opinions vary and enough confusion exists in terms of the methodology used to derive this metric as to question its uncritical adoption in investigations of ecotoxicology and stress ecology.
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Surface activity of extracellular products of a Pseudomonas aeruginosa isolated from petroleum-contaminated soil Author(s)- Anyanwu, Chukwudi U ABSTRACT Pseudomonas aeruginosa isolated from petroleum-contaminated soil of Nsukka, South-East Nigeria produces surface-active compounds when grown in different carbon sources tested. The surface properties of the culture supernatants of the isolate, using water-soluble and water-insoluble carbon sources as substrates are described in terms of surface tension and emulsification index. Water-soluble substrates showed better surface activity than water-insoluble substrates. The surface tension of the culture supernatants was lowest with glucose (34.5 dynes/cm) followed by sucrose (38.6 dynes/cm), glycerol (40.2 dynes/cm), fructose (41.8 dynes/cm), hexadecane (50.4 dynes/cm) and paraffin oil (56.4 dynes/cm). The culture supernatants showed emulsification index of between 52% and 85% and the emulsion formed remained stable during an extended ageing period of 30 days. The biosurfactants formed by the isolate retained surface active properties after exposure to high temperature (1000C), a wide range of pH (4 – 12) and high salinity (16%). Read full text
Estimation of above ground biomass in Indian tropical forested area using multi-frequency DLR-ESAR data
Author(s) – Vyjayanthi Nizalapur, Chandra Sekhar Jha and Rangaswamy Madugundu
This paper presents experimental results obtained with DLR-ESAR airborne data in C, L and P-bands over the parts of Gujarat, India. The aim is to estimate the above ground biomass and quantify various levels of above ground forest biomass with the help of empirical relationship of the backscattering coefficients and ground inventory. Extensive field data were collected to characterize forest vegetation parameters in the plots. Ground inventory data viz., GBH, tree height was collected. Plot level above ground tree biomass (AGB) is estimated from the collected ground data using the existing allometric equations at stand level in the study area. Regression analysis is carried out between above ground biomass and backscatter coefficient of C, L and P- bands in VV polarization. The obtained regression equation was used to estimate the above ground biomass from ESAR data in C, L and P- bands. Results showed that with increase in the biomass levels, backscattering coefficient also increases and C-band ESAR data is capable of predicting biomass up to 70 Mg/ha, L-band upto 150 Mg/ha and P-band upto 200 Mg/ha. Comparison of the estimated above ground biomass of airborne microwave DLR-ESAR data in C, L and P-bands was also carried out.
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