20 resultados para AGRICULTURAL PRODUCTIVITY
Resumo:
The base concept from which the entire research problem emerged is as follows: Lack of spatial planning and effective development management system lead to urban sprawl with non-optimal density of population to support urban infrastructure on the one side causing a lesser quality of life in urban areas. On the other side it causes loss of productivity of natural ecosystems and agricultural areas due to disturbance to the ecosystems. Planned compact high density development with compatible mixed land use can go a long way in achieving environmental efficiency of development management system.
Resumo:
The water quality and primary productivity of Valanthakad backwater (9° 55 10. 24 N latitude and 76° 20 01. 23 E longitude) was monitored from June to November 2007. Significant spatial and temporal variations in temperature, transparency, salinity, pH, dissolved oxygen, sulphides, carbon dioxide, alkalinity, biochemical oxygen demand, phosphatephosphorus, nitrate-nitrogen, nitrite-nitrogen as well as primary productivity could be observed from the study. Transparency was low (53.75 cm to 159 cm) during the active monsoon months when the intensity of solar radiation was minimum, which together with the run off from the land resulted in turbid waters in the study sites. The salinity in both the stations was low (0.10 ‰ to 4.69 ‰) except in August and November 2007. The presence of total sulphide (0.08 mg/ l to 1.84 mg/ l) and higher carbon dioxide (3 mg/ l to 17 mg/ l) could be due to hospital discharges and decaying slaughter house wastes in Station 1 and also from the mangrove vegetation in Station 2. Nitrate-nitrogen and phosphate-phosphorus depicted higher values and pronounced variations in the monsoon season. Maximum net primary production was seen in November (0.87 gC/ m3/ day) and was reported nil in September. The chlorophyll pigments showed higher values in July, August and November with a negative correlation with phosphate-phosphorus and nitrite-nitrogen. The study indicated that the water quality and productivity of Valanthakad backwater is impacted and is the first report from the region
Resumo:
Retting.of coconut husk is one of the major problems of pollution in the estuaries (Kayals) of Kerala. This paper discusses the salient features associated with the variation in gross and net primary productivity values in the Kadinarnkularn Kayal based on lortnightlydala from twosclected stations frorn Octobcr1987 to September 1988.The gross primary productivity value in the surface water ranged from 0.06 to 0.29gC/m3/day at Station Iand from 0.06 to 1.49gC/rn3/dayatstation II. In the bottom wateritrangcdfrorn oto 0.21 gC/m2/ day at station I whereas that at station II from 0.03 to 1.41gC/m3j day. The net productivity in the surface water at station I varied from 0 to 024 gC/m Iday Whereas that atstation II varied from 0.02to 1.44gC/m3Iday.AI the bottomwaterilvaried from ato 0.19gC/m3/ day at station I and from 0.01 to 1.21gC/m3/day at station II. The monsoon period showed the highest mean seasonal value at stations I and II. The total depletion of dissolved oxygen giving rise to anoxic condition coupled with the production of large quantities of hydrogen sulphide was found to be detrimental to the gross and net productivity values in the retting zone
Resumo:
The fertility of the coastal and estuarine waters is of great concern because of its influence on the productivity of these waters. Seasonal variations in the distribution of organic carbon, total nitrogen and total phosphorus in the sediments of Kuttanad Waters, a part of the tropical Cochin Estuary on the south west coast of India, are examined to identify the contribution of sediments to the fertility of the aquatic systems. The adjoining region has considerable agricultural activity. The fresh water zones had higher quantities of silt and clay whereas the estuarine zone was more sandy. Organic carbon, total phosphorus and total nitrogen were higher in the fresh water zones and lower in the estuarine zones. Total phosphorus and organic carbon showed the lowest values during monsoon periods. No significant trends were observed in the seasonal distributions of total nitrogen. Ratios of C/N, C/P and N/P, and the phosphorus and nitrogen content indicate significant modification in the character of the organic matter. Substantial amounts of the organic matter can contribute to reducing conditions and modify diagenetic processes
Resumo:
Bioethanol is a liquid fuel obtained from fermentation of sugar/starch crops. Lignocellulosic biomass being less expensive is considered a future alternative for the food crops. One of the main challenges for the use of lignocellulosics is the development of an efficient pre-treatment process. Pretreatments are classified into three - physical, chemical, and biological pretreatment. Chemical process has not been proven suitable so far, due to high costs and production of undesired by-products. Biologically, hydrolysis can be enhanced by microbial or enzymatic pretreatment. Studies show that the edible mushrooms of Pleurotus sp. produce several extracellular enzymes which reduce the structural and chemical complexity of fibre. In the present study, P. ostreatus and P. eous were cultivated on paddy straw. Spent substrate left after mushroom cultivation was powdered and used for ethanol production. Saccharomyces sp. was used for fermentation studies. Untreated paddy straw was used as control. Production of ethanol from P. ostreatus substrate was 5.5 times more when compared to untreated paddy straw, while the spent substrate of P. eous gave 5 times increase in ethanol yield. Assays showed the presence of several extracellular enzymes in the spent substrate of both species, which together contributed to the increase in ethanol yield