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Heat stroke is a serious heat‐related health outcome that can eventually lead to death. Due to the poor accessibility of heat stroke data, the large‐scale relationship between heat stroke and meteorological factors is still unclear. This work aims to clarify the potential relationship between meteorological variables and heat stroke, and quantify the meteorological threshold that affected the severity of heat stroke. We collected daily heat stroke search index (HSSI) and meteorological data for the period 2013–2020 in 333 Chinese cities to analyze the relationship between meteorological variables and HSSI using correlation analysis and Random forest (RF) model. Temperature and relative humidity (RH) accounted for 62% and 9% of the changes of HSSI, respectively. In China, cases of heat stroke may start to occur when temperature exceeds 36°C and RH exceeds 58%. This threshold was 34.5°C and 79% in the north of China, and 36°C and 48% in the south of China. Compared to RH, the threshold of temperature showed a more evident difference affected by altitude and distance from the ocean, which was 35.5°C in inland cities and 36.5°C in coastal cities; 35.5°C in high‐altitude cities and 36°C in low‐altitude cities. Our findings provide a possible way to analyze the interaction effect of meteorological variables on heat‐related illnesses, and emphasizes the effects of geographical environment. The meteorological threshold quantified in this research can also support policymaker to establish a better meteorological warning system for public health. Plain Language Summary: The impact of extreme heat events on population has become of urgent public health concern. In China, the real mortality and morbidity data are not publicly available and data of some diseases are not enough recorded. Thus, it is difficult to build a solid relationship between heat strokes and meteorological variables in large spatial scale. Internet search data, highly correlated with real heat stoke cases, was adopted as a new data set in our research instead of the heat‐related morbidity data to investigate the relationship between heat strokes and multiple meteorological variables. According to Random forest model, temperature and relative humidity (RH) were identified as the most important factor, which mainly affected the severity of heat strokes. We quantified the meteorological threshold that affected the severity of heat strokes as well. Heat strokes may start to occur when temperature exceeds 36°C and RH exceeds 58% in China. The temperature of this threshold is higher in the south or low‐latitude region or coastal region of China. This work provides new insights for health research and help to timely alert the public in adverse weather conditions. Key Points: Internet search data could help to evaluate the health impact in large scale to address the data shortageIncreasing temperature and relative humidity (RH) led to sharply increased heat stroke, particularly when maximum temperature exceeds 36°C and RH exceeds 58%Meteorological threshold was affected by geographical factors like altitude, latitude and distance from ocean [ABSTRACT FROM AUTHOR]

Sponge city planning aims to manage urban development land to prevent flooding and to support the achievement of water resource protection objectives. In this study, from the perspective of rainfall management demand and ability, we present an improved planning method, including two calculation models, aimed at determining the VCRAR (volume capture ratio of annual rainfall) and then integrating VCRAR requirements into the management of urban development land more accurately and objectively, while simultaneously considering the rainfall condition and urban planning attributes to support the implementation of sponge city planning. Compared to the current method, the VCRAR calculation model greatly improves the accuracy of the VCRAR for various space scales, and the conversion model solves the fundamental problem that urban land indicators corresponding to the VCRAR are difficult to calculate objectively and accurately. Moreover, this methodology can achieve a reasonable tradeoff between the development of individual districts and the environmental protection of the whole urban watershed, which allows a poetic vision to be turned into executable planning and design. The results of the application of this methodology in a case study in Jizhou, China, show that the improved method can make land utilization, development period and natural conditions more integrated and scientifically involved in the indicator calculation. The results also quantitatively show that the capacity of volume capture inside the site for one district increases as its green space ratio increases, and it decreases with an increase in the transformation difficulty for stormwater management facilities, when restricted by the investment and available space. [ABSTRACT FROM AUTHOR]

Land use and land cover (LULC) change in tropical regions can cause huge amounts of carbon loss and storage, thus significantly affecting the global climate. Due to the differences in natural and social conditions between regions, it is necessary to explore the correlation mechanism between LULC and carbon storage changes in tropical regions from a broader geographical perspective. This paper takes Hainan Island as the research object, through the integration of the CA-Markov and Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) models, based on multi-source data, analyses the dynamics of LULC and carbon storage from 1992 to 2019 and the relationship between the two, and predicts future LULC and carbon storage under different scenarios. The results show that (1) the built-up land area of Hainan Island expanded from 103.59 km2 to 574.83 km2 from 1992 to 2019, an increase of 454.91%; the area of cropland and shrubland decreased; and the area of forest increased. (2) Carbon storage showed an upward trend during 1992–2000, and a downward trend during 2000–2019. Overall, LULC changes during 1992–2019 reduced carbon storage by about 1.50 Tg. (3) The encroachment of cropland in built-up land areas is the main reason for the reduction of carbon storage. The conversion of shrubland to forest is the main driving force for increasing carbon storage. The increase and decrease of carbon storage have obvious spatial clustering characteristics. (4) In the simulation prediction, the natural trend scenario (NT), built-up land priority scenario (BP) and ecological priority scenario (EP) reduce the carbon storage of Hainan Island, and the rate of decrease is BP> NT > EP. The cropland priority scenario (CP) can increase the LULC carbon storage, and the maximum increase in 2050 can reach 0.79 Tg. This paper supplements and improves the understanding of the correlation between LULC and carbon storage changes in tropical regions, and can provide guidance for the optimization of LULC structure in tropical regions with high economic development from a low-carbon perspective. [ABSTRACT FROM AUTHOR]

The megacity of Shanghai faces enormous planning challenges, particularly controlling rapid urban growth and preserving some of the world's most fertile agricultural land. Almost two-thirds of Shanghai's territory is classified as agricultural land. Maintaining this high ratio of agricultural land to total land area and, at the same time, accommodating a large and rapidly increasing urban population represents an immense and complex planning challenge. Shanghai has recently adopted a Municipal Land Use Plan to address some of these planning challenges. This article provides a review, analysis and critique of Shanghai's Municipal Land Use Plan. From a review of the relevant literature, this article develops a framework to evaluate Shanghai's plan. This framework provides a qualitative assessment of the strengths and weaknesses of the SMLUP's overall goal of preserving arable land and fostering urban-economic development. [image omitted] [ABSTRACT FROM AUTHOR]

This article provides a detailed evaluation of Shanghai's municipal land-use plan (SMLUP). It fills a gap in the literature that has examined Shanghai's urban growth and economic restructuring, but has neglected to evaluate the city's municipal plan. This article sets the evaluation of the SMLUP within the administrative and institutional context of the preparation of comprehensive land-use plans in China as well as the extensive literature on Shanghai's urban spatial structure. It identifies a number of strengths and weaknesses of the SMLUP. Overall, the SMLUP was found to be a rather technical document that attempts to balance the supply of agricultural and development land. The discussion traces the weaknesses to poorly defined planning terms and concepts within the plan, as well as narrow regulations governing the creation of comprehensive land-use plans. Inconsistencies are also found between policies and objectives contained within the SMLUP and the Comprehensive Plan of Shanghai. The paper concludes that a more comprehensive and holistic plan evaluation framework is required if Chinese city-regions are to be governed by better land-use plans. [ABSTRACT FROM AUTHOR]

Mercury contamination from industrial and agricultural drainage into lakes and rivers is a growing concern in Northern China. Lake Ulansuhai, located in Hetao irrigation district in Inner Mongolia, is the only sink for the all industrial and agricultural drainage and sole outlet for this district to the Yellow River, which is one of the main source of drinking water for the numerous cities and towns downstream. Because Ulansuahi is ice-covered during winter, the QWASI model was modified by adding an ice equation to get a more accurate understanding of the fate and transport of mercury within the lake. Both laboratory and field tests were carried out during the ice growth period. The aquivalence and mass balance approaches were used to develop the modified QWASI + ice model. The margins of error between the modelled and the measured average concentrations of Hg in ice, water, and sediment were 30%, 26.2%, and 19.8% respectively. These results suggest that the new QWASI + ice model could be used to more accurately represent the fate and transport of mercury in the seasonally ice-covered lakes, during the ice growth period. [ABSTRACT FROM AUTHOR]

Highlights • Great variation of CWs design parameters and pollutant removal efficiencies in China. • Wastewater sources should be considered as important factors for design of CWs. • Regression equations of TSS, BOD 5 , COD cr , NH 3 -N, TN and TP with very low R2. Abstract Constructed wetlands (CWs), as an important ecological engineering technology, are designed and built to utilize the natural functions of wetlands for wastewater treatment within a more controlled environment. CWs have been widely used across the world. This review specifically aims at analyzing design parameters, pollutant removal efficiencies and their relationships for CWs built in China. The ANOVA analysis indicated that the design parameters and pollutant removal efficiencies were significantly different in different types of CWs and in different wastewater sources, and that wastewater sources should be considered as important factors for design of CWs operating parameters. Regression analysis of design parameters and pollutant removal efficiencies showed that regression equations were Logarithmic for total suspended solids (TSS), Power for ammonium (NH 3 -N), Compound for total nitrogen (TN) and Linear for biochemical oxygen demand (BOD 5), chemical oxygen demand (COD cr) and total phosphorous (TP). However, the correlation index (R2) was quite low because of poor correlativity between design parameters and removal efficiencies, probably because of the diverse nature of the data analyzed. The application of CWs is most appropriate and beneficial in decentralized wastewater treatment in small town and rural areas as well as for low polluted water of rivers and lakes due to low costs for construction, operation and maintenance. [ABSTRACT FROM AUTHOR]

CH 4 flux measured by a portable chamber using an infrared analyzer was compared with the flux by static chamber measurement for CW at 13 different sites from May 2012 to May 2017 in the Living Water Garden (LWG) in Chengdu, Sichuan Province, China, over 4 timescales (daily, monthly, seasonal, and annual). During the measurement period, a total of 1443 data were collected. CH 4 fluxes were measured using the portable chamber method and the results showed that the annual mean and median CH 4 flux values in the LWG were 17.4 mg m -2  h -1 and 6.2 mg m -2  h -1 , respectively, ranging from - 19.7 to 98.0 mg m -2  h -1 . Cumulative CH 4 emissions for LWG ranged from - 0.17 to 0.86 kg m -2  year -1 . Global warming potential (GWP, 25.7 kg CO 2eq m -2  year -1 ) was at a high level, which means that the LWG was a source of CH 4 emissions. Significant temporal variations on the 4 timescales were observed. And the asymmetry of measurement uncertainty of CH 4 flux increases with the timescale. Although the total mean CH 4 flux measured by the portable chamber method was 42.1% lower than that of the static chamber method, the temporal variation trends of CH 4 flux were similar. The uncertainty of CH 4 flux measured in portable chamber was more symmetrical than that in static chamber. These results suggest that the portable chamber method has considerable value as a long-term measurement method for CH 4 flux temporal variations.

It is very important to control methane emissions to mitigate global warming. An intermittent micro-aeration control system was used to control methane emissions from an integrated vertical-flow constructed wetland (IVCW) to treat agricultural domestic wastewater pollution in this study. The optimized intermittent micro-aeration conditions were a 20-min aeration time and 340-min non-aeration time, 3.9 m 3  h -1 aeration intensity, evenly distributed micro-aeration diffusers at the tank bottom, and an aeration period of every 6 h. Methane flux emission by intermittent micro-aeration was decreased by 60.7% under the optimized conditions. The average oxygen transfer efficiency was 26.73%. The control of CH 4 emission from IVCWs was most strongly influenced by the intermittent micro-aeration diffuser distribution, followed by aeration intensity, aeration time, and water depth. Scaling up of IVCWs is feasible in rural areas by using intermittent micro-aeration control as a mitigation measure for methane gas emissions for climate change.