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To analyze the efficiency of the agro-ecosystem of Dongting Rim in Hunan Province, this paper adopted the emergy theory to study the agricultural output of this region during 2001 to 2010. The results showed that the value of regional agricultural emergy output increased by 44.68% to (6.50 E) sej, but lower than the growth of non-agricultural industry output. Compared with 2001, the emergy output of planting industry was (4.10E) sej in 2010 which occupied 63.09% of the total agricultural emergy output and got an increase of 2.93 percentage points, while the emergy output of stock farming got a decrease of 2.87 percentage points. The growth of fishery emergy output was not in conformity with the characteristics of Dongting Rim in Hunan. From the contrast between emergy output and economic output, we could find that the economic return ratio of planting industry and fishery industry were lower than those of forestry industry and stock farming industry, which indicated that it is necessary to improve the economic benefits of planting industry and fishery industry which were the traditional industries with advantages of the Dongting Rim in Hunan. [ABSTRACT FROM AUTHOR]

Abstract: Emergy theory has its unique advantage in the research of regional economic system''s ecological efficiency. Namely, it can integrate ecological system and social economic system into one body so as to conduct unified statistical measurement and analysis on the real value of natural environment and human kind''s production activities, and therefore overcoming the shortcoming of only focusing on economic analysis. Based on the reference of previous researchers’ research literatures , this paper utilizes the relevent economic, social and environment statistics of Hunan province''s Agro-ecological system for the year of 2008, and carries out the computation and data processing of the input and output emergy for this system. And in the meantime, the authors also have analyzed the current situation of the input-output structure , the system''s load capacity , and the system''s operation efficiency among with other problems. This paper intents to lay a solid foundation for the future further research on the sustainable development of Hunan province''s Agro-ecological system. [Copyright &y& Elsevier]

Single-layer glauconites with thicknesses ranging from millimeters to centimeters have been widely developed in the Cambrian tidal flat-shoal environments in the Xuzhou area, northern China. The Cambrian glauconite-bearing sedimentary sequences in this area were combined to reconstruct the glauconite formation and its subsequent occurrence environments. Glauconites were generally formed in tidal flat-lagoon environments with low sedimentation rates and coexisted in oolitic shoals, intertidal flats, and subtidal flats, together with granular fractions formed under different types of strong hydrodynamic conditions. The glauconites occur in granular, micellar, and re-agglomerated granular forms with similar chemical compositions, consisting mainly of SiO 2 , FeO, Al 2 O 3 , and K 2 O. The Stage 4–Wuliuan is characterized by a hot climate, many types of glauconite, and large variations in maturity. The limestone, quartz sandstone, and silty mudstone all contain glauconite pellets. The glauconite with felsic material as the substrate has a pseudomorphic replacement genesis. The glauconite with mica as the substrate has a layer lattice theory genesis. The micellar glauconite may have been formed by loss of structural water during maturation of the glauconite pellets, i.e., biogenesis and authigenic precipitation genesis. The Guzhangian–Paibian is characterized by a warm climate, a single glauconite type, high maturity, and stability. The reagglomerated granular glauconite distributed in the dolomitic limestone and dolomite is mostly of grain verdissement origin. The ion contents released by the different substrates were different, and transportation also inhibited the glauconite development, making the degree of glauconization in the Cambrian unstable. The influence of substrate composition on glauconite maturity remains uncertain, but glauconites of stable size (∼100 μm), regular shape, and uniform color generally show higher and more stable levels of glauconitization. Glauconite has a robust temperature tolerance and can develop in environments characterized by weakly oxidizing to weakly reducing conditions, transgression-regression stage of sea level rise and flourishing biological conditions. The accumulation phase of glauconite may indicate a major transition in the Cambrian ecosystem. • The formation and occurrence environments of glauconite were reconstructed. • The forms of the glauconites in the Cambrian strata in the Xuzhou area were classified. • The chemical composition and genesis mechanism of the different types of glauconites were determined. • The factors influencing the formation of the Cambrian glauconites were determined. [ABSTRACT FROM AUTHOR]