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Shengli Oilfield has abundant low-permeability oil reservoirs with proven reserves of 1.18 billion tons， presenting a good prospect for development. However， there is a problem of inability to inject and produce during the development process of the oil reservoirs due to the low porosity， poor permeability， and strong heterogeneity of the low-permeability oil reservoir. A systematic review was conducted on the prediction and analysis methods for low-permeability oil reservoirs in Shengli Oilfield to achieve efficient development of low-permeability oil reservoirs， as well as efficient development technologies， and the advantages and disadvantages of existing technologies were analyzed to provide an outlook for the development technologies of low-permeability oil reservoirs. Based on research and practice， the following conclusions are drawn： ① Shengli Oilfield has developed fine reservoir characterization technologies such as reservoir prediction， in-situ stress prediction， and evaluation of reservoir heterogeneity. ② Based on theoretical and technological innovation， the physical limit of reserve production was constantly broken， forming differential development technology series， such as water injection development technology of horizontal wells in ultra-low permeability oil reservoirs， long well section multi-stage fracturing development technology of horizontal wells in tight oil reservoirs， well pattern adaptation technology for enhanced oil recovery of general low-permeability oil reservoirs， pressure flooding technology in low-permeability tight oil reservoirs， and viscous emulsion-surfactant flooding technology. Good development results have been achieved. ③ Combined with the actual needs of high-quality development and speed and efficiency improvement development of low-permeability oil reservoirs in Shengli Oilfield， the well pattern reconstruction technology of dual control streamline variation， CCUS technology， and nanobubble flooding technology were proposed， pointing out the development direction for improving oil recovery of low-permeability oil reservoirs.

As an important ecological barrier in the Guangdong-Hong Kong-Macao Greater Bay Area, Shimentai Nature Reserve aims to protect the integrity of the ecosystem and biodiversity. It was established as a provincial-level nature reserve in 1998 and upgraded to a national level nature reserve in 2012. However, the changes in the quality of the ecological environment remain unclear. This study quantitatively assessed the changes in the ecological quality of the Shimentai Nature Reserve from 1997 to 2021 based on the Remote Sensing Ecological Index (RSEI), explored the changes in ecological quality before and after the establishment of the nature reserve and the upgrading of the control level, and discussed the reasons for the evolution using the Random Forest Algorithm and correlation analysis method. The results showed that the RSEI value of Shimentai Nature Reserve dynamically increased from 0.637 in 1997 to 0.714 in 2011, and the ecological environment quality steadily improved as the nature reserve was upgraded from the provincial to the national level; the RSEI reached 0.788 by 2021. The quality of the ecological environment has improved in 64.5% of the protected area, the buffer zone has improved more obviously, and the deteriorated areas are mainly concentrated in the experimental area where human activities are frequent and in the high-altitude ridge area in the core area. Meanwhile, the ecological environment quality of the buffer zone and the low-altitude area in the core area is adequate and relatively stable. The RSEI responded most clearly to elevation, with the best ecological quality between 300 and 600 m and relatively poorer quality above 900 m. On the slope upward with the south slope as the turning point, the quality of the ecological environment gradually improved from the north slope to the south slope in a clockwise direction, and then gradually deteriorated from the south slope to the north slope. At a cut-off point of 15° on the slope, the RSEI briefly increased and then decreased continuously. The RSEI was highest at a soil pH of 5.3, organic carbon mass fraction of 4.1%, and clay mass fraction of 32%. The degree of influence of residential activities on the quality of the ecological environment from the outside to the inside (i.e., the experimental area-buffer area-core area) was gradually reduced and negatively affected. The RSEI was positively correlated with precipitation, 23.6% of the area passed the significance test (P < 0.05). The local year was influenced by precipitation, and the influence of precipitation was greater in certain years. Overall, the ecological environment quality of the Shimentai Nature Reserve has shown a clear improvement trend, and the protection and management of the bare soil areas on the top of the high mountains, and the areas of frequent human activities in the lower altitudes, should be strengthened in the future.

Wheat straw (WS) has long been subjected to rough treatment by traditional incineration, which not only results in the waste of biomass resources but also poses a risk of atmospheric pollution and is not conducive to the sustainable utilization of natural resources. With great humification potential, WS can be utilized as a valuable composting material. The study optimized the C/N ratio by mixing WS and chicken manure (CM) as composting raw materials, and found that this method could significantly improve the compost quality. In comparison to the conventional poplar woodchip (PW) conditioning, the incorporation of WS resulted in an elevated composting temperature, an extended high-temperature period, a more expeditious lignocellulose degradation, a notable enhancement in the organic matter content, a suppression of hydrogen sulfide production under low C/N ratio, and a promotion of elemental sulfur conversion, collectively contributing to an enhanced overall quality and environmental friendliness of the compost. Correlation analysis of microbial communities and environmental factors demonstrated that the mixed compost facilitated the growth of actinomycetes and sulfur-transforming bacteria. Additionally, structural equation model indicated that parameters such as temperature and pH value played a key role in the composting process. [ABSTRACT FROM AUTHOR]

The CO2 efflux from forest soil (FCO2) is one of the largest components of the global carbon cycle. Accurate estimation of FCO2 can help us better understand the carbon cycle in forested areas and precisely predict future climate change. However, the scarcity of field-measured FCO2 data in the subtropical forested area greatly limits our understanding of FCO2 dynamics at regional and global scales. This study used an automatic cavity ring-down spectrophotometer (CRDS) analyzer to measure FCO2 in a typical subtropical forest of southern China in the dry season. We found that the measured FCO2 at two experimental areas experienced similar temporal trends in the dry season and reached the minima around December, whereas the mean FCO2 differed apparently across the two areas (9.05 vs. 5.03 g C m−2 day−1) during the dry season. Moreover, we found that both abiotic (soil temperature and moisture) and biotic (vegetation productivity) factors are significantly and positively correlated, respectively, with the FCO2 variation during the study period. Furthermore, a machine-learning random forest model (RF model) that incorporates remote sensing data is developed and used to predict the FCO2 pattern in the subtropical forest, and the topographic effects on spatiotemporal patterns of FCO2 were further investigated. The model evaluation indicated that the proposed model illustrated high prediction accuracy for the training and testing dataset. Based on the proposed model, the spatiotemporal patterns of FCO2 in the forested watershed that encloses the two monitoring sites were mapped. Results showed that the spatial distribution of FCO2 is obviously affected by topography: the high FCO2 values mainly occur in relatively high altitudinal areas, in slopes of 10–25°, and in sunny slopes. The results emphasized that future studies should consider topographical effects when simulating FCO2 in subtropical forests. Overall, our study unraveled the spatiotemporal variations of FCO2 and their driving factors in a subtropical forest of southern China in the dry season, and demonstrated that the proposed RF model in combination with remote sensing data can be a useful tool for predicting FCO2 in forested areas, particularly in subtropical and tropical forest ecosystems. [ABSTRACT FROM AUTHOR]

Introduction: Microplastics (MPs), identified as emerging contaminants, have been detected across diverse environmental media. Their enduring presence and small size facilitate the adsorption of organic pollutants and heavy metals, leading to combined pollution effects. MPs also accumulate in the food chain thus pose risks to animals, plants, and human health, garnering significant scholarly attention in recent years. Aerobic granular sludge (AGS) technology emerges as an innovative approach to wastewater treatment. However, the impacts of MPs on the operational efficiency and microbial characteristics of AGS systems has been insufficiently explored., Methods: This study investigated the effects of varying concentration (10, 50, and 100 mg/L) of biodegradable MPs (Polylactic Acid, PLA) and non-biodegradable MPs (Polyethylene Terephthalate, PET) on the properties of AGS and explored the underlying mechanisms., Results and Discussions: It was discovered that low and medium concentration of MPs (10 and 50 mg/L) showed no significant effects on COD removal by AGS, but high concentration (100 mg/L) of MPs markedly diminished the ability to remove COD of AGS, by blocking most of the nutrient transport channels of AGS. However, both PLA and PE promoted the nitrogen and phosphorus removal ability of AGS, and significantly increased the removal efficiency of total inorganic nitrogen (TIN) and total phosphorus (TP) at stages II and III ( P < 0.05). High concentration of MPs inhibited the growth of sludge. PET noticeably deteriorate the sedimentation performance of AGS, while 50 mg/L PLA proved to be beneficial to sludge sedimentation at stage II. The addition of MPs promoted the abundance of Candidatus&#95;Competibacter and Acinetobacter in AGS, thereby promoting the phosphorus removal capacity of AGS. Both 50 mg/L PET and 100 mg/L PLA caused large amount of white Thiothrix filamentous bacteria forming on the surface of AGS, leading to deterioration of the sludge settling performance and affecting the normal operation of the reactor. Comparing with PET, AGS proved to be more resistant to PLA, so more attention should be paid to the effect of non-biodegradable MPs on AGS in the future., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Guo, Ma, Niu, Li, Wang, Ma, Cai, Li and Li.)