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This paper differs from conventional science and socially oriented studies of climate by integrating concepts derived from both approaches. Based on interdisciplinary, trans-disciplinary multidisciplinary literature review, it defines microclimate and its essences of including natural, social and interactive microclimate from tourism discipline context. For in-depth development of tourism in China under the pressure of tourism supply-side structure revolution, this paper proposes microclimate tourism and analyzes basic on-site microclimate tourism mechanism, basic tourists attractions supply mechanism, and dynamic flows and flexible organisation mechanism of microclimate tourism. For sustainable development, it explores tangible tourists attractions safety, tourists safety and industrial security of microclimate tourism as well as measurements and suggestions for mitigating relative security and safety issues. • Defining climate and microclimate concept from tourism discipline perspective. • Analyzing microclimate tourism mechanisms in on-site, basic tourists attraction supply, dynamic flow situations. • Analyzing tangible tourists attractions, tourists and industrial security and safety of microclimate tourism. • Proposing measures and suggestions for sustainable development of microclimate tourism security and safety. [ABSTRACT FROM AUTHOR]

[Display omitted] • A numerical model is proposed for seasonal thermal energy storage (STES) couple with solar collector. • The model is featured as relatively high computational speed and accuracy. • An analysis on technical planning and operational design for the STES is offered. • The key parameters for system design and control are investigated with instructive results. Seasonal thermal energy storage (STES) systems are a key component in expanding the share of renewables in energy programs because they provide schedulability and flexibility. However, such a large-scale system requires careful planning to avoid high investment costs. Therefore, numerical models are becoming increasingly important as an alternative. This paper develops a numerical model of STES coupled with solar collector. The model was verified based on the experimental data of the Huangdicheng Project in China. The results show that the relative error in the charging mode and discharging mode is only 1.57 % and 0.46 %, respectively. Then, the effects of different charging and discharging mode on the heat storage efficiency of the tank and the efficiency of solar collector systems in STES were studied. The study found that in the initial charging stage, the water temperature rise curve caused by different flow rates is very different. In the design of the collector-storage area ratio, the relatively economical collector-storage ratio of this model is around 3768 L/m2. The selection of different proportions of discharging energy in the discharge stage has a great impact on the heat storage efficiency of the system in the next year. Moreover, the influence of different depth-diameter ratios of the tank on the system heat storage efficiency is discussed in detail, which has important guiding significance for model application and system analysis. This paper provides some references for the scale design and operation optimization of cylindrical STES. [ABSTRACT FROM AUTHOR]

As one of the most intensively eroded regions worldwide, soil erosion assessment is currently gaining further momentum in the Loess Plateau (LP), China. However, there exist very few review studies that assess soil erosion in relation to land use and land cover (LULC), climate, and ecosystem services (ESs) at multiple temporal and spatial scales in the LP. Thus, this review provides a comprehensive review of the interactions among soil erosion assessment, climate change, LULC change, and ESs at different scales. We focused on the academic literature published in the English language and analyzed the coverage of soil erosion across 109 publications. Our results highlighted three aspects: (1) studies dealing with the effects of LULC change on soil erosion are abundant. A recent surge in research interest is to explore a threshold of vegetation cover to support a sustainable eco-hydrological environment in the LP. However, the impacts of multiple stressors on soil erosion have received limited attention. (2) The short-term soil erosion assessment dominated the published studies. Cross-spatial-scale and long-term erosion assessments have received little attention. (3) 43% of reviewed papers used a field measurement method to assess soil erosion with the validation of measurement methods. 41% of reviewed papers used empirical models to assess soil erosion, but the modeling validation remains an unsolved problem. Then, three recommendations are listed as follows: (1) the combined impacts of LULC and climate change on soil erosion need to be further examined. (2) Long-term and cross-spatial-scale soil erosion assessments need to be established. (3) Soil erosion modeling accuracy on a large scale needs to be developed. • The assessment of multiple stressors on soil erosion has received limited attention. • Poor coverage of multi-spatial scale and long-term soil erosion assessment. • Large scale soil erosion modeling validation remains an unsolved problem. • A recent surge in academic interest is to explore thresholds of vegetation cover in the Loess Plateau. [ABSTRACT FROM AUTHOR]

Abstract: A cover with capillary barrier effects (CCBEs) is a promising final cover for controlling water infiltration into a waste containment system. A CCBE consisting of a layer of fine soil and a layer of coarse soil relies on the particle size contrast of the two soils. Although CCBEs have been successfully used in dry climate, their performance under high precipitation intensities and high evaporation conditions (e.g., in South China) is still unclear. This paper aims to evaluate the performance of the CCBE in high-precipitation areas and propose appropriate combinations of local soils for constructing a CCBE in South China. Several combinations of lean clay, clayed sand, and silty sand with gravel are examined using saturated/unsaturated seepage analysis. Two contrasting conditions, i.e., a drizzle lasting for a long time and an intense storm lasting for a short time, are applied to the covers. The covers perform well when subject to prolonged small rainfall at an initial maximum suction of 150kPa. When subject to a short-time heavy rainfall, breakthrough occurs in the cover consisting of clayed sand overlying silty sand with gravel. Of the three covers, a CCBE consisting of lean clay overlying silty sand with gravel performs well under both prolonged light rainfall and short time heavy rainfall conditions. This CCBE has the longest period of time before breakthrough and the least amount of percolated water under prolonged heavy rainfall. [Copyright &y& Elsevier]

Abstract: In the regions surrounding the Qinghai Tibet Plateau, changes in erosion rates have been linked to the tectonics, climate and topography over different time scales. To understand the mechanisms governing the changes of erosion rates, it is important to study erosion rates by different methods and for different time scales. In inland drainage basins, deposition rates of terminal lake sediments can indicate basin-wide erosion rates at the millennial-scale. This paper presents three lake records of the Last Deglaciation and Holocene (Huahai Lake, Zhuye Lake and Yanchi Lake) from the Hexi Corridor, north of the Qilian Mountains, in arid China. Organic matter, terrestrial pollen concentrates, seeds, grasses and plant debris are used for conventional and AMS 14C dating. On the basis of 66 radiocarbon dates, lithology and grain-size, we infer relatively high basin-wide erosion rates during the Last Deglaciation and early Holocene in the three drainage basins, when the three lake sediments were seriously affected by reworking. The deposition rates were an order of magnitude or greater in these lakes during the Last Deglaciation and early Holocene than during the mid-to-late Holocene. During the transition period of the last glacial–interglacial cycle, significant climatic changes occurred in East and Central Asia, corresponding to the strengthening of the Asian summer monsoon and to increasing effective moisture in arid Central Asia, which can have strong impacts on basin-wide erosion rates north of the Qinghai Tibet Plateau. Moreover, melting glaciers in the Qilian Mountains probably also contributed to the high basin-wide erosion rates. At the same time, tectonic activity was not recognizable in the study area during that period. In the arid and semiarid regions surrounding the Qinghai Tibet Plateau, dramatic changes in erosion rates appear during the transition periods of the glacial–interglacial cycles, which illustrate the climatic controls on erosion rates at this time scale. [Copyright &y& Elsevier]

Abstract: The relationships between climate, topography, and erosion are significant in understanding landscape evolution. In order to study this relationship in a tectonically active landscape, the details of 11 drainage basins were collected from Qilian Shan Mountains. Decadal-scale erosion rates, including the mechanical load and solute load contributions, are estimated in natural conditions. The calculated erosion rates show that the average erosion rate of Qilian Shan Mountains is about 0.08mm/yr, while the variation of annual erosion rates within each basin is significant. The changes of topography and climate, which potentially control erosion rates, are also employed in this paper for correlating analyses. Correlation analyses indicate that erosion rates are more closely correlated with topographic variables, such as mean local relief and mean slope, than all of the climatic variables; and mean local relief and decadal-scale erosion rates show a linear relationship in these tectonically active mountains. However, some topographic variables like basin area and elongation ratio exert limited influence on erosion rates; while others, such as basin elevation, basin relief and basin roughness, show poor correlation. The results indicate that topographic control, like aspects of the local terrain steepness, plays the most important role in spatial distribution of decadal-scale erosion rates throughout Qilian Shan Mountains. Under topographic control, some climatic variables, like discharge and runoff, however, could account for the significant variation of annual erosion rates in individual basin. When comparing erosion rates on different timescales, we found that the decadal-scale erosion rates are lower than the long-term river incision rates, as well as the exhumation rates during early and middle Miocene. The change to more arid climatic condition since the middle Miocene combining with tectonic uplift should attribute to the inconsistent erosion rates over different timescales in Qilian Shan Mountains. [Copyright &y& Elsevier]

Abstract: Understanding the sensitivity of soil respiration to temperature change and its impacting factors is an important base for accurately evaluating the response of terrestrial carbon balance to future climatic change, and thus has received much recent attention. In this study, we synthesized 161 field measurement data from 52 published papers to quantify temperature sensitivity of soil respiration in different Chinese ecosystems and its relationship with climate factors, such as temperature and precipitation. The results show that the observed Q 10 value (the factor by which respiration rates increase for a 10°C increase in temperature) is strongly dependent on the soil temperature measurement depth. Generally, Q 10 significantly increased with the depth (0cm, 5cm, and 10cm) of soil temperature measuring point. Different ecosystem types also exhibit different Q 10 values. In response to soil temperature at the depth of 5cm, alpine meadow and tundra has the largest Q 10 value with magnitude of 3.05±1.06, while the Q 10 value of evergreen broadleaf forests is approximately half that amount (Q 10 =1.81±0.43). Spatial correlation analysis also shows that the Q 10 value of forest ecosystems is significantly and negatively correlated with mean annual temperature (R =−0.51, P <0.001) and mean annual precipitation (R =−0.5, P <0.001). This result not only implies that the temperature sensitivity of soil respiration will decline under continued global warming, but also suggests that such acclimation of soil respiration to warming should be taken into account in forecasting future terrestrial carbon cycle and its feedback to climate system. [Copyright &y& Elsevier]

Peatlands are one of the most significant carbon reservoirs in the terrestrial ecosystem. Understanding past peatland carbon accumulation processes and their responses to varying external and internal forcing factors would help reveal the general development patterns of peatland ecosystems and provide useful insights into projecting the fate of carbon reservoirs into the future. In this paper, the basal ages of 17 peat cores were used to explore the lateral expansion processes of the Laolike peatland, northeast China. Two cores were selected to calculate carbon accumulation rates (CAR) and reconstruct moisture/precipitation records based on δ13C and grain size analyses. The basal ages show that the peatland was initiated at 12.1 cal kyr BP, then laterally expanded with its fastest rate occurring during the early Holocene, and reached its largest area around 6 cal kyr BP. The time-weighted mean CAR in the Laolike peatland ranged from 31.1 to 52.9 g C/m2/yr (with an average of 42 g C/m2/yr) during the Holocene. The peatland experienced a high CAR of 52.5 g C/m2/yr from 11.7 to 5 cal kyr BP, followed by a low CAR of 35.1 g C/m2/yr after 5 cal kyr BP. Both lateral expansion and vertical accretion are consistent with the summer insolation, climate seasonality, and the strength of the East Asia summer monsoon (EASM) over multi-millennium timescales, where the CAR correlated well with δ13C and grain size, implying moisture/precipitation might be the primary factors controlling carbon accumulation over millennium timescales. Local conditions, such as topography and hydrology, also played an important role in the process of peatland initiation and lateral expansion, as well as the discrepant CAR within the peatland. This study reveals the roles of climate and local conditions in peatland initiation, expansion, and CAR during the Holocene. In addition, we provide a window for a better understanding of the driving factors of peatland development in the temperate zones of the Northern Hemisphere. • Climate conditions are the primary control on the lateral expansion and vertical accretion of Laolike peatland over multi-millennium timescales. • Moisture/precipitation affects carbon accumulation of Laolike peatland over millennium timescales. • Local conditions play an important role in the lateral expansion and the internal differences of carbon accumulation rate. [ABSTRACT FROM AUTHOR]

Summary: Objectives: This paper was aimed at examining the relationship between meteorological variables and bacillary dysentery in different climatic and geographic areas in China. Methods: Jinan in northern China, with a temperate climate, and Baoan in southern China, with a subtropical climate were chosen as study areas. Spearman correlations and seasonal Autoregressive Integrated Moving Average (SARIMA) models were used to quantify the association between meteorological variables and dysentery. The Hockey Stick model was used to explore the threshold of the effect of temperatures. Results: Maximum temperature, minimum temperature, rainfall, relative humidity and air pressure were significantly correlated with the incidence of dysentery in the both cities, with lag effects varying from zero to two months. In the SARIMA models, maximum and minimum temperatures were significantly associated with dysentery transmission. The thresholds for the effects of maximum and minimum temperatures were 17°C and 8°C, respectively, in the northern city. No thresholds were detected in the southern city. Conclusions: Climate variations have different impacts on the transmission of bacillary dysentery in temperate and subtropical cities in China. Public health action should be taken at this stage to reduce future risks of climate change with consideration of local climatic conditions. [Copyright &y& Elsevier]