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Setting a production target for a two-stage production–pollutant control system can provide guidance for the system to achieve efficient performance in its future production. The existing studies have succeeded in targeting but have missed the consideration of coordination between the adjustments for the two stages' input and output metrics. In this article, we propose an approach to address this problem using a non-parametric method: data envelopment analysis. First, we use the leader–follower analysis from game theory to propose slacks-based measure models for production target setting in situations where a dominance relationship exists between the two stages of the systems. Based on the results generated by the leader–follower models, we define each stage's dissatisfaction degree with the set targets. Further, considering the coordination between the adjustments of the two stages' inputs and outputs, we incorporate the bargaining game theory to propose a model which can generate the set of coordinated adjustments that is a bargaining solution taking account of both the dissatisfaction degrees of the two stages. The properties of the solution generated by the bargaining model feature fairness, which makes the target setting result coordinated between each system's two stages. Finally, the proposed approaches are applied and tested in an empirical study of 30 provincial regions in China. [ABSTRACT FROM AUTHOR]

Abstract: To evaluate the sulfur (S) biological cycle status in the marshes of the intertidal zone, this study explored the S biogeochemical processes in the two Suaeda salsa marshes [middle S. salsa marsh (MSM) and low S. salsa marsh (LSM)] of the Yellow River estuary during April 2008 to November 2009. Results showed that soil S fluctuated seasonally and varied with depth in both MSM and LSM. The variations in S content in different parts of plant were significantly influenced by water and salinity. The S. salsa litter in MSM and LSM released S to the decomposition environment throughout the year. The S absorption coefficients of S. salsa in MSM and LSM were very low (0.0031 and 0.0004, respectively), while the S biological cycle coefficients were high (0.9014 and 0.8625, respectively). The S turnovers among compartments of MSM and LSM indicated that the uptake amounts of roots were 1.237 and 0.160gm−2 yr−1 and the values of aboveground parts were 3.885 and 1.276gm−2 yr−1, the re-translocation quantities from aboveground parts to roots were 2.770 and 1.138gm−2 yr−1, the translocation amounts from roots to soil were 0.154 and 0.018gm−2 yr−1, the translocation quantities from aboveground living bodies to litter were 1.115 and 0.138gm−2 yr−1, and the annual return quantities from litter to soil were less than 1.096 and 0.188gm−2 yr−1, respectively. Although S was not a limiting nutrient in S. salsa marshes, its high biological cycle rate might significantly inhibit the production and emission of methane (CH4), which had important significances to reduce CH4 emission from the Yellow River estuary. The S quantitative relationships determined in the compartment model might provide some scientific basis for us to reveal the special inhibition mechanism in future studies. [Copyright &y& Elsevier]

Abstract: The spatial and temporal variations of the fluxes of nitrous oxide (N2O) and methane (CH4) and associated abiotic sediment parameters were quantified for the first time across the coastal marsh dominated by Suaeda salsa in the Yellow River estuary during 2009/2010. During all times of day and the seasons measured, N2O and CH4 fluxes from coastal marsh ranged from −0.0147mgN2Om−2 h−1 to 0.0982mgN2Om−2 h−1 and −0.7421mgCH4 m−2 h−1 to 0.4242mgCH4 m−2 h−1, respectively. The mean N2O fluxes in spring, summer, autumn and winter were 0.0325mgN2Om−2 h−1, 0.0089mgN2Om−2 h−1, 0.0119mgN2Om−2 h−1 and 0.0140mgN2Om−2 h−1, and the average CH4 fluxes were −0.0109mgCH4 m−2 h−1, −0.0174mgCH4 m−2 h−1, −0.0141mgCH4 m−2 h−1 and −0.0089mgCH4 m−2 h−1, respectively, indicating that the coastal marsh acted as N2O source and CH4 sink. Both N2O and CH4 fluxes differed significantly between times of day of sampling. N2O fluxes differed significantly between sampling seasons as well as between sampling positions, while CH4 fluxes had no significant differences between seasons or positions. Temporal variations of N2O emissions were probably related to the effects of vegetation (S. salsa) during summer and autumn and the frequent freeze/thaw cycle of sediment during spring and winter, while those of CH4 fluxes were controlled by the interactions of thermal conditions and other abiotic factors (soil moisture and salinity). Spatial variations of N2O and CH4 fluxes were primarily affected by soil moisture fluctuation derived from astronomic tide, sediment substrate and vegetation composition. N2O and CH4 fluxes, expressed as CO2-equivaltent (CO2-e) emissions, showed that N2O comprised the principal part of total calculated CO2-e emissions during spring and winter, while the contributions of CH4 could not be ignored during summer and autumn. This study highlights the importance of seasonal N2O and CH4 contributions, particularly during times of significant CH4 consumption. For the accurate up-scaling of N2O and CH4 fluxes to annual rates, a careful sampling design at site-level is required to capture the potentially considerable temporal and spatial variations of N2O and CH4 emissions. [Copyright &y& Elsevier]