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China launched seven emissions trading scheme (ETS) pilots in 2011, and a national ETS, at the end of 2017 in an attempt to reduce its greenhouse gas emissions (GHGs) and drive its extensive energy transition in a cost-effective way. The Hubei province pilot ETS has operated since 2014, and an analysis of its effectiveness can provide lessons for the nascent national system. This paper disaggregates Hubei's industrial carbon dioxide (CO 2) emissions from 2005 to 2018 into economic scale, economic structure, energy efficiency, and energy structure effects using the logarithmic mean Divisia index (LMDI). Difference-in-difference (DID) models then assess the implementation effectiveness of this ETS, and its impact on the main influencing factors of the LMDI. Ten cities each in the Hubei and Hunan provinces are selected as treatment and control groups, respectively, in the DID models. Results show that the change in industrial CO 2 emissions is mainly due to the economic scale and energy efficiency effects. After the ETS implementation, the energy structure effect has a limited impact on emissions, while the economic structure effect makes a negligible contribution. Moreover, the implementation of the ETS has had little demonstrable impact on industrial CO 2 emissions, gross domestic product (GDP), energy consumption intensity, and CO 2 emission intensity. This lacking of impact is caused by the GHG monitoring capacity deficits of the local Development and Reform Commission, and irrational quota allocations. Effective supervision and quota allocation should be developed to increase the impacts of the ETS. [ABSTRACT FROM AUTHOR]

Land use/land cover (LULC) changes driven by diverse policies in arid ecologically fragile areas have sizeable impacts on agricultural production and water-related ecosystem services (ESs) and their trade-offs. However, the relative and cumulative impacts of diverse policies on ESs and their trade-offs in different periods are still unclear and need further differentiation. The western Jilin Province, China was taken as a case study, and actual LULC conversions associated with policy implementation rules were selected to disentangle the relative and cumulative impacts of diverse policies on food- and water-related ESs and their trade-offs in the historical (2000–2010) and recent (2010–2020) periods. Policies that have the greatest impact on ESs trade-offs at county scale in different periods were further identified. The results showed that food production improved the most (203.50%), but habitat quality (−7.79%) and water purification (−7.61%) decreased the most in the food security plan (FSP) during 2000–2020. Habitat quality improved the most (3.73%) in the river-lake connection program (RLCP), and water purification improved the most (3.85%) in the Grain for Green (forest) program (GFGP). The impact of diverse policies on ESs in the historical period was generally greater than that in the recent period. The cumulative impact of the ecological protection and restoration improved all ESs. While the saline-alkali land amelioration program (SLAP) mitigated most ES trade-offs in the historical period, all ecological protection and restoration policies enhanced most ES trade-offs in the recent period. Policies that have the greatest impact on ESs and their trade-offs varied over time. The SLAP and RLCP have immense potential to improve ESs and their trade-offs. This study can serve as a reference for future agricultural development and ecological protection and restoration strategies in arid areas. [Display omitted] • Land use/cover pattern under each policy was mapped based on implementation rules. • Relative impacts of diverse policies on ecosystem services were disentangled. • Impact of policies on ecosystem services and their trade-offs was time-sensitive. • River-lake connection programs had great potential to improve ecosystem services. • Policies have the greatest impact on ecosystem service trade-offs varied over time. [ABSTRACT FROM AUTHOR]

Swamp wetlands play a pivotal role in conserving water sources, regulating river runoff, and maintaining water safety and balance. The study pioneers a new research framework in the field of pollution ecology of swamp wetlands, with a focus on the complex "source-transfer-sink" processes affecting water quality in micro swamp wetlands, an area previously under-researched. Taking the Momoge Wetland in the Songnen Plain as an example, we innovatively combined the "source-transfer-sink" theory with landscape patterns, topographic factors, and their impacts on wetland water quality. Using Partial Least Squares Structural Equation Modeling (PLS-SEM), our research quantifies and models the relationships among various environmental factors. This approach reveals how landscape patterns influence pollutant migration and water quality at a micro-scale. Our findings suggest that a 700-m buffer zone is most effective in capturing the fluctuations in water quality in arid wetlands, which is crucial for wetland management practices. We identified the main pollution sources in the Momoge Wetland, including sediment (21.60%), vegetation (24.94%), livestock and crop-related non-point sources (41.21%), and hydrodynamic factors such as water diversion (12.25%). In pollutant migration, land use emerged as the most significant factor affecting water quality (56.64%), followed by landscape patterns (25.54%). Notably, our study finds that grasslands are essential for water purification, and a uniform distribution of landscape patches significantly improves water quality. This research marks a significant stride in understanding and optimizing landscape patterns to enhance water quality in micro swamp wetlands. The insights gained are invaluable for the protection of these ecosystems and promoting their ecological value functions, providing a reference point for future wetland conservation and management strategies. [Display omitted] • "Source-Transfer-Sink" theory explains the decline in water quality in small micro wetlands. • Revealing water quality fluctuations by combining source apportionment and landscape patterns during migration. • 700m buffer zone is optimal for controlling water quality in small micro wetlands. • Increased grassland area improves water quality in small micro wetlands. • Uniform distribution among different patches enhances water quality. [ABSTRACT FROM AUTHOR]