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To stabilize global mean temperature change within the range of 1.5-2.0°C in accordance with the Paris Agreement, countries worldwide submitted their Intended Nationally Determined Contributions with their proposed emission reductions. However, it remains unclear what the resulting climate change in terms of temperature and precipitation would be in response to the Intended Nationally Determined Contribution emission efforts. This study quantifies the global and regional temperature and precipitation changes in response to the updated Intended Nationally Determined Contribution scenarios, using simulations of 14 Fifth Coupled Climate Model Intercomparison Project models. Our results show that Intended Nationally Determined Contribution emissions would lead to a global mean warming of 1.4°C (1.3-1.7°C) in 2030 and 3.2°C (2.6-4.3°C) in 2100, above the preindustrial level (the 1850-1900 average). Spatially, the Arctic is projected to have the largest warming, 2.5 and 3 times the global average for 2030 and 2100, respectively, with strongest positive trends at 70-85°N over Asia, Europe and North America (6.5-9.0°C). The excessive warming under Intended Nationally Determined Contribution scenarios is substantially above the 1.5°C or 2.0°C long-term stabilization level. Global mean precipitation is projected to be similar to preindustrial levels in 2030, and an increase of 6% (4- 9%) by 2100 compared with the preindustrial level. Regional precipitation changes will be heterogeneous, with significant increases over the equatorial Pacific (about +120%) and strong decreases over the Mediterranean, North Africa and Central America (-15% - -30%). These results clearly show that it is necessary to adjust and strengthen national mitigation efforts on current Intended Nationally Determined Contributions to meet the long-term temperature target. [ABSTRACT FROM AUTHOR]

Phenology-driven events, such as spring wildflower displays or fall tree colour, are generally appreciated by tourists for centuries around the world. Monitoring when tourist seasons occur using satellite data has been an area of growing research interest in recent decades. In this paper, a valid methodology for detecting the grassland tourist season using remote sensing data was presented. On average, the beginning, the best, and the end of grassland tourist season of Inner Mongolia, China, occur in late June (±30 days), early July (±30 days), and late July (±50 days), respectively. In south region, the grassland tourist season appeared relatively late. The length of the grassland tourist season is about 90 days with strong spatial trend. South areas exhibit longer tourist season. [ABSTRACT FROM AUTHOR]

Depending on the descriptions of crop yield and social response to crop failure/harvest from Chinese historical documents, we classified the crop yield of North China during 601-900 AD into six categories and quantified each category to be the crop yield grades. We found that the regional mean crop yield had a significant (P < 0.01) negative trend at the rate of-0.24% per decade. The interannual, multiple-decadal, and century-scale variability accounted for ~47%, ~30%, and ~20% of the total variations of crop yield, respectively. The interannual variability was significantly (P < 0.05) persistent across the entire period. The multiple-decadal variability was more dominant after 750 AD than that before 750 AD, while the century-scale variability was more dominant before 750 AD than that after 750 AD. The variations of crop yield could be partly explained by temperature changes. On one hand, the declining trend of crop yield cooccurred with the climate cooling trend from 601 to 900 AD; on the other hand, the crop yield was positively correlated with temperature changes at 30-year resolution with the correlation coefficient of 0.59 (P < 0.1). These findings supported that high (low) crop yield occurred in the warming (cooling) climate. [ABSTRACT FROM AUTHOR]

To understand the effects of the land use/cover changes due to agricultural development on summer climate in Eastern China, four 12-year simulations using the WRF-SSiB model were performed. We found that agricultural development resulted in warming and rainy effects. In the middle to lower reaches of the Yellow River and the Yangtze River, the warming effects were approximately 0.6°C and resulted from increased surface net radiation and sensible heat fluxes. In Northeast China, the warming effects were very small due to increases in latent heat fluxes which resulted from the extensive conversion from grassland to cropland. The rainy effect resulted from increases in convective rainfall, which was associated with a warming surface in certain areas of the Yellow River and Yangtze River and a large increase in the surface moisture flux in Northeast China. Conversely, in the middle to lower reaches of the Yellow River and the Yangtze River, the grid-scale rainfall decreased because the climatological northward wind, which is moist and warm, was partially offset by a southward wind anomaly. These findings suggest that the agricultural development left footprints not only on the present climate but also on the historical climate changes before the industrial revolution. [ABSTRACT FROM AUTHOR]

The article discusses the reconstruction of climate using a variety of historical documents in China. It is stated that there were 14 published temperature series by different studies that were examined for coherence and mutual consistency. The analyses revealed that for the individual time series on the 10-year time scales, 57 of the 91 correlation coefficients attain the implication level of 99%. Furthermore, consistency also show when equating the reconstructions with other available natural climate change indicators.

In light of the observed climate changes in recent decades over eastern China, we studied the changes in spring phenophases of woody plants observed at 16-stations during 1963-1996, and explored the possible link between the spring phenophases changes and climate changes before the phenophase onset. It is found that, in the region north of 33°N (including Northeast, North China and the lower reaches of the Huaihe River), the phenophase advanced 1.1-4.3 days per decade for early spring and 1.4-5.4 days per decade for late spring, but in the eastern part of the southwest China it was dealyed by 2.9-6.9 days per decade in early spring and 2.4-6.2 days per decade in late spring. One outstanding feature is identified in Guangzhou in south China, where significant advance of 7.5 days per decade in early spring and delay of 4.6 days per decade in late spring were detected. Statistically siginficant correlation was found between the changes of spring phenophase and the temperatures of one or several months before the phenophase onset. The relationship between the trend of phenophase change and temperature change was highly nonlinear (more sensitivity to cooling than to warming) and reached an asymptote 0.5°C per decade, which may have implication in the responses of the ecosystem in a future global warming scenario. In addition, we also examined the link between the spring phenophase, and length and mean temperature of the growing season, and the analyses suggested that they were highly correlated as well. [ABSTRACT FROM AUTHOR]

Temperature change of the past 2000 years in China is discussed based on the winter half-year temperature series of the past 2000 years in eastern China reconstructed recently, and other related studies. The main conclusions are as follows: (1) The Little ice Age (LIA) in China began in the early of the 14th century (1320s) and ended in the beginning of the 20th century (1910s), which was composed of four evident cold stages and three short warming stages. The cold period in the Wei, Jin and South-North dynasties (210s∼560s) was the only one comparable with LIA for the past 2000 years. (2) The Medieval Warm Period (MWP) in China began in the 930s and ended in the 1310s, which was composed of two warm stages over 100 years and a cold stage less than 100 years. (3) The climate in the Sui and Tang dynasties should be divided into two stages: the climate in the 570s∼770s was as warm as that in the 20th century; while the temperature in the 780s∼920s was lower than that in the 1950s∼1970s. (4) In eastern China as a whole, winter half-year temperature variation with over 1°C occurred between the cold and warm stages on centennial scale, while the changing rate exceeded 1.0°C per century. (5) There exists an about 1350-year periodicity in the historical temperature change. Inferred from the periodicity, the most likely historical analogue for the warming in the 20th century is the warm stage of the Sui and Tang dynasties (570s∼770s), instead of the Medieval Warm Period. (6) Although it was critically warm, the temperature of the 20th century in eastern China is still within the threshold of the variability of the last 2000 years. [ABSTRACT FROM AUTHOR]

Phenological cold/warm events recorded in Chinese historical documents are used to reconstruct, at 10–30 years' resolution, winter half-year (October to April) temperatures for the past 2000 years in the central region of eastern China. Because of the uneven spatial and temporal distribution of the phenological records, the reconstruction of the regional mean temperature involves two steps: reconstruction for individual sites within the region and calculation of the regional mean. For a single site, the reconstruction involves: identifying the difference in dates in phenological events for both historical and modern records; establishing the conversion function between the date difference and temperature change from the modern records; and converting the historical records into temperature variation. The spatial representativeness of the individual sites is studied by examining the correlation between individual sites and regional mean temperature from modern instrumental data. The correlation is then used as the basis for constructing the regional mean winter half-year temperature for the past 2000 years. From the beginning of the Christian era, climate became cooler at a rate of 0.17°C per century, and around the AD 490s temperature reached about 1°C lower than that of the present (the 1951– 80 mean). Then, abruptly, temperature entered a warm epoch from the AD 570s to 1310s with a warming trend of 0.04°C per century; the peak warming was about 0.3–0.6°C higher than present for 30-year periods, but over 0.9°C warmer on a 10-year basis. After the AD 1310s, temperature decreased rapidly at a rate of 0.10°C per century; the mean temperatures of the four cold troughs were 0.6–0.9°C lower than the present, with the coldest value 1.1°C lower. Temperature has been rising rapidly during the twentieth century, especially for the period 1981–99, and the mean temperature is now 0.5°C higher than for 1951–80. The most interesting aspect over the past 2000 years has been the rapid transitions between cold and warm periods. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau, recognized as Earth's third pole and among the most responsive regions to climate shifts, profoundly influences regional and even global hydrological processes. Here, we discerned a significant weakening in the influence of temperature on the initiation of surface freeze-thaw cycle (the Start of Thawing, SOT), which can be ascribed to a multitude of climatic variables, with radiation emerging as the most pivotal factor. Additionally, we showed that the diminishing impact of warming on SOT yields amplified soil moisture within the root zone. This, in turn, fosters a greening third pole with increased leaf area index and solar-induced chlorophyll fluorescence. We further showed that current Earth system models failed to reproduce the linkage between weakened sensitivity and productivity under various shared socioeconomic pathways. Our findings highlight the dynamic shifts characterizing the influence of climate warming on spring freeze-thaw process and underscore the profound ecological implications of these changes in the context of future climate scenarios. [ABSTRACT FROM AUTHOR]

Attribution of compound events informs preparedness for emerging hazards with disproportionate impacts. However, the task remains challenging because space-time interactions among extremes and uncertain dynamic changes are not satisfactorily addressed in the well-established attribution framework. For attributing the 2020 record-breaking spatially compounding flood-heat event in China, we conduct a storyline attribution analysis by designing simulation experiments via a weather forecast model, quantifying component-based attributable changes, and comparing with historical flow analogs. We quantify that given the large-scale circulation, anthropogenic influence to date has exacerbated the extreme Mei-yu rainfall in the mid-lower reaches of the Yangtze River during June-July 2020 by ~6.5% and warmed the co-occurring seasonal extreme heat in South China by ~1°C. Our projections show a further intensification of the compound event by the end of this century, with moderate emissions making the rainfall totals ~14% larger and the season ~2.1°C warmer in South China than the 2020 status. [ABSTRACT FROM AUTHOR]

Proxy-based precipitation reconstruction is essential to study the inter-annual to decadal variability and underlying mechanisms beyond the instrumental period that is critically needed for climate modeling, prediction, and attribution. Based on 3014 annually resolved proxy series mainly derived from tree-ring and historical documents, we present a set of standard precipitation index (SPI) reconstructions for annual (Nov-Oct) covering entire Asia and for wet season (i.e., Nov-Apr for western Asia and May-Oct for the others) with the spatial resolution of 2.5° since 1700. To screen the optimal candidate proxies for SPI reconstruction in each grid from available proxies in its connected region with a homogeneous rainfall regime and similar precipitation variability, a new approach is develop by adopting the grid-location-dependent division derived from the instrumental SPI data. The validation shows that these reconstructions are effective for most of Asia. The assessment of data quality compared with gauge precipitation before calibration time indicates that our reconstruction has high quality to show the precipitation variability in most of the study areas except for few grids in western Russia, the coastal area of southeastern Asia and northern Japan. [ABSTRACT FROM AUTHOR]

In order to understand past plant phenological responses to climate change in China (1963-2009), we conducted trends analysis of spring phenophases based on observation data at 33 sites from the Chinese Phenological Observation Network (CPON). The phenological data on first leaf date (FLD) and first flowering date (FFD) for five broad-leaved woody plants from 1963 to 2009 were analyzed. Since most phenological time series are discontinuous because of observation interruptions at certain period, we first interpolated phenological time series by using the optimal model between the spring warming (SW) model and the UniChill model to form continuous time series. Subsequently, by using regression analysis, we found that the spring phenophases of woody plants in China advanced at a mean rate of 0.18 days/year over the past 50 years. Changes of spring phenophases exhibited strong regional difference. The linear trends in spring phenophases were -0.18, -0.28, -0.21, -0.04, and -0.14 days/year for the Northeast China Plain, the North China Plain, the Middle-Lower Yangtze Plain, the Yunnan-Guizhou Plateau, and South China, respectively. The spatial differences in phenological trends can be attributed to regional climate change patterns in China. [ABSTRACT FROM AUTHOR]

Continuous satellite datasets are widely used in tracking vegetation responses to climate variability. Start of season (SOS), for example, can be derived using a number of methods from the time series of satellite reflectance data; however, various methods often produce different SOS measures which limit the application of satellite data in phenological studies. Therefore, we employed five methods to estimate SOS from the Advanced Very High Resolution Radiometer (AVHRR)/normalized difference vegetation index (NDVI) dataset. Subsequently, we compared the SOS with the ground-based first leaf date (FLD) of 12 deciduous broadleaved plant species at 12 sites of the Chinese Phenological Observation Network (CPON). The results show that the latitudinal patterns of five satellite-derived SOS measures are similar to each other but different from the pattern of ground phenology. For individual methods, the variability of SOS time series is significantly different from ground phenology except for HANTS, Polyfit, and Midpoint methods. The SOS calculated using the Midpoint method showed significant correlations with ground phenophases most frequently (in 47.1% of cases). Using the SOS derived from the Midpoint method, significantly earlier trends in SOS were detected in 50.7% of the natural vegetation area from 1982 to 2006. [ABSTRACT FROM AUTHOR]

Global climate change is likely to alter the phenological patterns of plants due to the controlling effects of climate on plant ontogeny, especially in an urbanized environment. We studied relationships between various phenophases (i.e., seasonal biological events) and interannual variations of air temperature in three woody plant species ( Prunus davidiana, Hibiscus syriacus, and Cercis chinensis) in the Beijing Metropolis, China, based on phenological data for the period 1962–2004 and meteorological data for the period 1951–2004. Analysis of phenology and climate data indicated significant changes in spring and autumn phenophases and temperatures. Changes in phenophases were observed for all the three species, consistent with patterns of rising air temperatures in the Beijing Metropolis. The changing phenology in the three plant species was reflected mainly as advances of the spring phenophases and delays in the autumn phenophases, but with strong variations among species and phenophases in response to different temperature indices. Most phenophases (both spring and autumn phenophases) had significant relationships with temperatures of the preceding months. There existed large inter- and intra-specific variations, however, in the responses of phenology to climate change. It is clear that the urban heat island effect from 1978 onwards is a dominant cause of the observed phenological changes. Differences in phenological responses to climate change may cause uncertain ecological consequences, with implications for ecosystem stability and function in urban environments. [ABSTRACT FROM AUTHOR]

Two methods to reconstruct seasonal precipitation are developed in terms of the soil surface water balance and field infiltration experiment by artificial rainfall. Seasonal and annual precipitation for the period of 1736 ∼1910 are reconstructed from snow and rainfall archives in the Qing Dynasty through both methods. The seasonal precipitation series from 1736 to 2000 is also established. The results show that the time series of seasonal precipitation obtained from both methods are statistically significant and consistent, implying that the seasonal precipitation can be reconstructed accurately from snow and rainfall archives in the Qing Dynasty by the above two methods, and thus the Chinese precipitation data in a large area would be extended to the early 18th century from 20th century (instrumental observation period). [ABSTRACT FROM AUTHOR]

Wheat is one of the most common and productive crops in the world, and the growth and production of wheat are sensitive to climate change. Climate change affects wheat phenology by influencing sowing/maturity dates and the duration of growing stages, and ultimately affects the grain yield. Reliable prediction of changes in wheat yield is significant for maintaining global food security. However, studies addressing the potential impact of crop phenology changes on grain yield are rarely reported, which is a big challenge. Using the CERES-Wheat model and first-order differential equation models, we quantified the impact of future climate change on wheat phenology and grain yield for two periods (P1: 2011-2040; P2: 2041-2070) under three representative concentration pathways (RCP2.6, RCP4.5, RCP8.5) in China's twomain wheat-growing areas (Northwest SpringWheat-Growing Area(NWSWA) and Huang-Huai-Hai Winter Wheat-Growing Area (HHWWA)); the baseline period was 1981-2010. Accumulated thermal time during thewhole growing period (WGP) tends to significantly increase in NWSWA and HHWWA under all RCPs and periods. This rising accumulated thermal time will reduce the time to anthesis and maturity and shorten the vegetative growing period (VGP), reproductive growing period (RGP), and theWGP. In P2, spring wheat grain yield is projected to diminish by a regional average of 2.67% for RCP2.6, 4.07% for RCP4.5, and 5.66% for RCP8.5, which is dominated by the lower accumulated solar radiation during the VGP in NWSWA. Additionally, for the winter wheat grain yield in HHWWA in P2, its grain yield reduction is projected to decline by 4.8% (RCP2.6), 7.9% (RCP4.5), and 9.8% (RCP8.5), which is caused by increasing accumulated thermal time in the VGP. These results suggest that breeding high-temperature-tolerant varieties with high calorie requirements is an adaptive strategy to mitigate the negative impact of climate change on wheat yield in the study areas. [ABSTRACT FROM AUTHOR]

The article presents the change of extreme snow events shaped the roof of traditional Chinese architecture in the past millennium. Topics discussed include show periodic change and a positive trend in roof slope of traditional buildings in the northern part of central and eastern China; and this study provides an excellent example showing how humans have long been aware of the impact of climate change on daily life and learned to adapt to it.

The high northern latitudes (>50°) experienced a pronounced surface stilling (i.e., decline in winds) with climate change. As a drying factor, the influences of changes in winds on the date of autumn foliar senescence (DFS) remain largely unknown and are potentially important as a mechanism explaining the interannual variability of autumn phenology. Using 183,448 phenological observations at 2,405 sites, long-term site-scale water vapor and carbon dioxide flux measurements, and 34 y of satellite greenness data, here we show that the decline in winds is significantly associated with extended DFS and could have a relative importance comparable with temperature and precipitation effects in contributing to the DFS trends. We further demonstrate that decline in winds reduces evapotranspiration, which results in less soil water losses and consequently more favorable growth conditions in late autumn. In addition, declining winds also lead to less leaf abscission damage which could delay leaf senescence and to a decreased cooling effect and therefore less frost damage. Our results are potentially useful for carbon fluxmodeling because an improved algorithm based on these findings projected overall widespread earlier DFS than currently expected by the end of this century, contributing potentially to a positive feedback to climate. [ABSTRACT FROM AUTHOR]

The land surface characteristic influences climatic environments by controlling the land surface energy and water fluxes. Although large progresses have been made in coupling detailed crop models into land surface models, there is much room left for improved estimates of surface fluxes in double cropping system, such as the winter wheat (Triticum aestivum L.)–summer maize (Zea mays L.) system under intensive influences of climate change and human activities in the North China Plain (NCP). Here, we modeled the growth and surface fluxes in winter wheat–summer maize double cropping system in the NCP through modified SiBcrop model. The parameters related with the crop growth in winter wheat and maize sub-models were emphasized to better simulate the seasonal dynamics of phenology phase, leaf area index (LAI), and latent (LH) and sensible (SH) heat fluxes. Observational data for phenology, LAI, and energy fluxes were compiled from Yucheng and Guantao stations, to calibrate and validate the SiBcrop model. The results showed that the adjusted SiBcrop captured better the seasonal dynamics of phenology, LAI, LH, and SH, relative to the original code. The largest biases in model results were in SH when horizontal advection prevails and in LH when there is summer maize senescence. Sensitivity analysis illustrated that growth duration, emergence date, LH, SH, and Bowen ratio were quite sensitive to sowing date of wheat, and growth duration and emergence and harvest dates to sowing of maize. The calibrated SiBcrop also simulated the LH and SH well at Guantao station. The adjusted SiBcrop is capable of assessing the responses of surface biophysical processes to the changes of human management and climate change in the double cropping system in the NCP. [ABSTRACT FROM AUTHOR]

As one of the most populous countries, China has policies protecting the amount of land available for crop production, but it does not consider the quality of land. Thus, an important issue is the impact on crop production by land use change under such policies and by notable climate variability during the past decades. Using a productivity attenuation method, we estimated the climatic productivity of winter wheat (WWCP) in the North China Plain, based on land use classification data and daily weather data from 1980 to 2010. Impacts of historic climate variability and land use change on WWCP were quantified. Results indicate: (1) on average, WWCP for newly-increased dry land was lower than that for the lost land, which may result in reduced land quality associated with conversion. (2) In recent years, the increasing area of dry land provided sufficient wheat yield to compensate for the loss resulted from reduction of WWCP. (3) Both historic climate variability and land use change decreased WWCP, but the effects of the latter (within -1%) were less than those of the former (about -3%). Given the scarce land resource and rapidly growing food demand, the approach through expanding the area of cultivated land to maintain grain yield is not a long-term guarantee of food security. Thus, cultivated land conservation policy should shift from protecting land quantity into preserving land productivity. In addition, agriculture policies should further emphasize the critical role of adaptation strategies in coping with climate change. Obtaining higher yield production will depend upon adopting adaptation measures which could effectively mitigate effects of dramatic climate change or even take advantage of possible climate conditions. [ABSTRACT FROM AUTHOR]

Forestry ecological engineering projects in Western China include the Three-North Shelter Forest Project (TNSFP), the Natural Forest Protection Project (NFPP), the Grain for Green Project (GGP) and the Beijing-Tianjin Sandstorm Source Project (BTSSP). Such projects play an important role in the control of dust weather in Western China. In this research, data on the frequency of sandstorms, sand-blowing and dust-floating weather, the area of four forestry ecological engineering projects, wind, rainfall and vegetation coverage from 2000 to 2010 were collected based on the unit of prefecture-level cities in Inner Mongolia. The panel-data model was used to analyze the quantitative association between forestry ecological engineering and dust weather. The results indicate that wind has a strong promotional effect on dust weather, while forestry ecological engineering and rainfall have a containment effect. In addition, the impacts of the four studied forestry ecological engineering projects on dust weather differ. For every increase of 1000 km 2 in the Three-North Shelter Forest Project, the annual number of days of sandstorm weather decreased by 4 days. Similarly, for every increase of 1000 km 2 in the Beijing-Tianjin Sandstorm Source Project, the sand-blowing weather decreased by 4.4 days annually. In addition, NFPP and GGP have a more obvious inhibitory effect on the dust-floating weather. [ABSTRACT FROM AUTHOR]

The Paris Agreement proposes a 1.5 °C target to limit the increase in global mean temperature (GMT). Studying the population exposure to droughts under this 1.5 °C target will be helpful in guiding new policies that mitigate and adapt to disaster risks under climate change. Based on simulations from the inter-Sectoral Impact Model Intercomparison Project (ISI-MIP), the standardized precipitation evapotranspiration index (SPEI) was used to calculate drought frequencies in the reference period and 1.5 °C global warming scenario. Then population exposure was evaluated by combining drought frequency with simulated population data from shared socioeconomic pathways (SSPs). In addition, the relative importance of climate and demographic change and the cumulative probability of exposure change were analyzed. Results revealed that population exposure to droughts on the east side of the Hu line is much more than on the west side; exposure in the middle and lower reaches of the Yangtze River region is the highest and lowest in the Qinghai-Tibet region. An additional 6.97 million people will be exposed to droughts under the 1.5 °C global warming scenario relative to the reference period. Demographic change is the primary contributor to exposure (79.95 %) in the 1.5 °C global warming scenario, more than climate change (29.93 %) or the interaction effect (-9.88 %). Of the three drought intensities, mild, moderate, and extreme, moderate droughts contribute the most to exposure (63.59 %). The frequency of extreme droughts is likely to decrease (71.83 % probability), while mild and moderate droughts may increase slightly (55.17 % and 51.71 % probability, respectively) in the 1.5 °C global warming scenario. [ABSTRACT FROM AUTHOR]

Cellular automaton (CA) is an important method in land use and cover change studies, however, the majority of research focuses on the discovery of macroscopic factors affecting LUCC, which results in ignoring the local effects within the neighborhoods. This paper introduces a Local Land Use Competition Cellular Automata (LLUC-CA) model, based on local land use competition, land suitability evaluation, demand analysis of the different land use types, and multi-target land use competition allocation algorithm to simulate land use change at a micro level. The model is applied to simulate land use changes at Jinshitan National Tourist Holiday Resort from 1988 to 2012. The results show that the simulation accuracies were 64.46%, 77.21%, 85.30% and 99.14% for the agricultural land, construction land, forestland and water, respectively. In addition, comparing the simulation results of the LLUC-CA and CA-Markov model with the real land use data, their overall spatial accuracies were found to be 88.74% and 86.82%, respectively. In conclusion, the results from this study indicated that the model was an acceptable method for the simulation of large-scale land use changes, and the approach used here is applicable to analyzing the land use change driven forces and assist in decision-making. [ABSTRACT FROM AUTHOR]

Phenology can be used to track plant responses to climate change. In China, several studies have found the earlier trends of spring phenophases over the past 50 years. However, few studies put these phenological changes into historical perspective. Based on specific phenophases records from historical diaries and Chinese Phenological Observation Network, we developed spring phenology index (SPI) time series in temperate and subtropical regions of eastern China from 1850 to 2009. We firstly compare the temporal change of SPI and seasonal temperature anomaly. Subsequently, we search for common shifts in phenological and temperature time series by applying the moving t-test method, and discuss temperature sensitivity of SPI by using the moving linear regression method for both regions. Results show that the SPI in temperate region revealed lower interannual variability than in subtropical region, while the seasonal temperature variability was higher in temperate region. In temperate region, the timing of significant shift towards earlier SPI (in 1979) coincides with the timing of shift in spring temperature time series. The temperature sensitivities of SPI differ among the two regions. The mean sensitivity of SPI to spring temperature in subtropical region (-3.7 days °C-1) is stronger than in temperate region (-2.5 days °C-1). The temperature sensitivity of SPI varies among consecutive 30-year periods. In recent three decades, temperature sensitivity of spring phenophases became stronger in both regions. [ABSTRACT FROM AUTHOR]

Spatiotemporal simulation of tourist town growth is important for research on land use/cover change under the influence of urbanization. Many scholars have shown great interest in the unique pattern of driving urban development with tourism development. Based on the cellular automata (CA) model, we simulated and predicted the spatiotemporal growth of Sanpo town in Hebei Province, using the tourism urbanization growth model. Results showed that (1) average annual growth rate of the entire region was 1.5Ha2 per year from 2005 to 2010, 4Ha2 per year from 2010 to 2015, and 2.5Ha2 per year from 2015 to 2020; (2) urban growth rate increased yearly, with regional differences, and had a high degree of correlation with the Euclidean distance of town center, traffic route, attractions, and other factors; (3) Gougezhuang, an important village center in the west of the town, demonstrated traffic advantages and increased growth rate since 2010; (4) Magezhuang village has the largest population in the region, so economic advantages have driven the development of rural urbanization. It showed that CA had high reliability in simulating the spatiotemporal evolution of tourist town, which assists the study of spatiotemporal growth under urbanization and rational protection of tourism resources. [ABSTRACT FROM AUTHOR]

Land use patch generalization is the key technology to achieve multiscale representation. We research patches and achieve the following. (1) We establish a neighborhood analysis model by taking semantic similarity between features as the prerequisite and accounting for spatial topological relationships, retrieve the most neighboring patches of a feature using the model for data combination, and thus guarantee the area of various land types in patch combination. (2)We establish patch features using nodes at the intersection of separate feature buffers to fill the bridge area to achieve feature aggregation and effectively control nonbridge area deformation during feature aggregation. (3) We simplify the narrow zones by dividing them from the adjacent feature buffer area and then amalgamating them into the surrounding features. This effectively deletes narrow features and meets the area requirements, better generalizes land use features, and guarantees simple and attractivemaps with appropriate loads. (4)We simplify the feature sidelines using the Douglas-Peucker algorithm to effectively eliminate nodes having little impact on overall shapes and characteristics. Here, we discuss the model and algorithm process in detail and provide experimental results of the actual data. [ABSTRACT FROM AUTHOR]

It is generally understood that foxtail millet and broomcorn millet were initially domesticated in Northern China where they eventually became the dominant plant food crops. The rarity of older archaeological sites and archaeobotanical work in the region, however, renders both the origins of these plants and their processes of domestication poorly understood. Here we present ancient starch grain assemblages recovered from cultural deposits, including carbonized residues adhering to an early pottery sherd as well as grinding stone tools excavated from the sites of Nanzhuangtou (11.5-11.0 cal kyBP) and Donghulin (11.0-9.5 cal kyBP) in the North China Plain. Our data extend the record of millet use in China by nearly 1,000 y, and the record of foxtail millet in the region by at least two millennia. The patterning of starch residues within the samples allow for the formulation of the hypothesis that foxtail millets were cultivated for an extended period of two millennia, during which this crop plant appears to have been undergoing domestication. Future research in the region will help clarify the processes in place. [ABSTRACT FROM AUTHOR]