SOC Vertical Distribution Pattern of Economic Plants in the Loess Gully Areas of China

Three economic plants from the loess gully areas in China to explore the changing vertical distribution characteristics of soil organic carbon.The results showed that:(1) with the increase of depth,the average SOC content of economic plants decreased from 13.98 to 1.39 g/kg on the 0-100 cm soil profile,in the form of a power function;(2) the constructed depth spatial distribution models for different plants could help accurately assess the spatial distribution pattern of soil organic carbon;(3) compared with traditional agricultural planting,the carbon sink function for walnut and grape at a soil depth of 100 cm increased by 92.8±8.98 t/hm^(2) and 45.7±7.7 t/hm^(2),respectively.The adjustment of agricultural planting structure increases the content of soil organic carbon,and economic plants are of great significance to enhance the carbon sink function of the agricultural ecosystem in the loess gully area.

Linear programming approach for optimal forest plantation

The aim of this research was to identify species suitable for plantation. We first identified species for potentially suitable for plantation based on ecological capabilities regarding soil properties. We determined the area of plantation for different species based on ecological capabilities. Then, we collected relevant data such as growth patterns of different species, labor requirements for plantation and plantation cost. A linear programming model and two integer linear programming models were used for optimization. The appropriate species based on ecological capabilities were ash, elm, maple, oak and bald cypress. A linear programming model was used based on ecological capabilities classification to determine the land area of different species for plantation. Then, two integer linear programming models were employed to select the species for plantation. We set ecological properties unequal for all of the species in the first run of the integer programming model. Two groups were classified： group one included maple and ash; group two included bald cypress,oak and elm. The second integer programming model assumed equal ecological properties for all the species.Results of linear programming showed that maple and bald cypress were appropriate for plantation at the site and their plantation areas should be 151.3 and 355.3 ha, respectively. Results of the first integer linear programming model showed that maple and bald cypress would be economically profitable for plantation. The results of the second integer linear programming model showed that only bald cypress would be appropriate for plantation.

Viability of a concentrated solar power system in a low sun belt prefecture

Concentrating solar power(CSP)is considered as a comparatively economical,more efficient,and large capacity type of renewable energy technology.However,CSP generation is found restricted only to high solar radiation belt and installed where high direct normal irradiance is available.This paper examines the viability of the adoption of the CSP system in a low sun belt region with a lower direct normal irradiance(DNI).Various critical analyses and plant economics have been evaluated with a lesser DNI state.The obtained results out of the designed system,subjected to low DNI are not found below par,but comparable to some extent with the performance results of such CSP plants at a higher DNI.The analysis indicates that incorporation of the thermal energy storage reduces the levelized cost of energy(LCOE)and augments the plant capacity factor.The capacity factor,the plant efficiency,and the LCOE are found to be 32.50%,17.56%,and 0.1952$/kWh,respectively.