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Urban parks have been considered as an effective measure to mitigate the urban heat island (UHI) effects. Many studies have investigated the impacts of shape, size and interior components on the cold island effect (CIE) of parks, while little attention has been given to the impact of neighboring buildings. Thus, taking twenty-two parks in Beijing as samples, this study investigated the impacts of the neighboring building on the CIE of central parks. The results showed that the average land surface temperature (LST) of parks are 30.98 &deg, C in summer and &minus, 1.10 &deg, C in winter. Parks have a strong CIE in summer, and average cold island footprint (CIF) and LST difference are 0.15 km2 and 2.01 &deg, C higher than that in winter. The components of the building in the CIF of parks are dominated by middle-rise building (MRB), followed by low-rise building (LRB), and high-rise building (HRB) is the least dominant. The percentage of landscape (PLAND) and landscape shape index (LSI) of MRB, and perimeter area fractal dimension (PAFRAC) of LRB are significantly related to CIF in summer and winter. This study could extend scientific understanding of the impacts of neighboring buildings on the CIE of central parks, and could guide urban planners in mitigating the UHI effects through the rational allocation of buildings.

Urban Heat Island (UHI), a phenomenon characterized by significantly higher air and land surface temperatures (LSTs) in urban areas than in suburban areas, results in land use change from non-urban to urban land and is accompanied by increases in anthropogenic heat release. A variety of land use contribution indexes have been proposed to quantitatively calculate the impact of land use types on UHI. However, these indexes can only show the impact of specific land use types on UHI. In fact, the area and the intensity (which also can be considered as the average temperature) of land use change jointly determine the regional UHI. The purpose of this paper is to develop an algorithm to quantitatively reveal the influence of the area and the intensity of land use change on regional UHI. MODIS LST products and 1:1,000,000 land use data sets were used to quantitatively calculate the seasonal and interannual contributions of land use change on regional UHI between 2005 and 2018 in China. These results have theoretical and practical significance for further understanding the formation mechanism of urban thermal environment and its mitigation measures.

Population migration and urban traffic are two important aspects of the socioeconomic system. We analyze the trends of social production and resumption of life after the coronavirus disease 2019 (COVID-19)-influenced Spring Festival in 2020 with statistics on reported cases of COVID-19 from China’s National Health Commission and big data from Baidu Migration (a platform collecting population migration data). We find that (1) the distribution of COVID-19 cases throughout mainland China has a specific spatial pattern. Provinces in eastern China have more reported cases than those in western China, and provinces adjacent to Hubei have more confirmed COVID-19 cases than nonadjacent provinces. Densely populated regions with well-developed economies and transportation are more likely to have cluster infection incidents. (2) The COVID-19 epidemic severely impacts the return of the migrant population in the Spring Festival travel rush, as demonstrated by the significant reduction in the return scale, along with the extended timespan and uncertainty regarding the end of the travel rush. Among 33 provinces, special administrative regions, autonomous regions and municipalities, 23 of them (approximately 70%) have a return rate below 60%. Hubei, Hong Kong, Xinjiang, and Inner Mongolia have the lowest return rates (below 5%), whereas the return rates in Hainan and Shandong, 272.72% and 97.35%, respectively, indicate the best trend of resumption. Due to government regulations, the population return in densely populated and well-developed regions shows a positive trend. (3) The resumption of urban traffic is slow and varies greatly in different regions. The urban traffic conditions in 22 provinces and municipalities have a more than 60% level of resumption. Guizhou and Yunnan have the highest level of resumption of urban traffic, whereas Xinjiang, Hubei, and Heilongjiang have the lowest (29.37%, 35.76%, and 37.90%, respectively). However, provinces and municipalities with well-developed intercity traffic have a lower level of resumption, mainly because of regulatory methods such as lockdowns and traffic restrictions. The increased public awareness of epidemic prevention and the decreased frequency of outdoor activities are also two positive factors slowing the spread of the epidemic. (4) Time will be necessary to fully resume social production and life throughout China. Xining and Jinan have the highest levels of resumption, 82.14% and 71.51%, respectively. Urumqi and Wuhan are the cities with the lowest levels of resumption, only 0.11% and 0.61%, respectively. Currently, 12 of 33 provinces and municipalities have levels of resumption of more than 80%; among them, Guizhou, Yunnan, and Gansu have with the highest levels of resumption and have nearly resumed the 2019 levels of work and life, whereas Xinjiang and Hubei have the lowest resumption rates, only 0.09% and 7.57%, respectively. Thus, relevant government departments should focus more on densely populated and well-developed provinces and cities when applying epidemic prevention and work resumption methods. We reveal the general conditions of the epidemic and the population return scale across China, along with urban traffic conditions and the resumption of social production and life under COVID-19, providing a scientific basis for local governments to make further decisions on work resumption.

Currently, most regional thermal environment (RTE) studies in urban agglomerations focus on developing countries, especially China. However, there is still a lack of comparative studies on the RTEs of urban agglomerations between China and other developed countries, such as the United States. This paper used the Beijing-Tianjin-Hebei (BTH) agglomeration in China and Boswash (the highly urbanized area extending from Boston to Washington) in the United States as examples to investigate the differences in land development patterns, RTEs and their relationship between the agglomerations of China and America. The results showed that the land development patterns of BTH and Boswash were different, as evidenced by the spatial pattern of land development intensity (LDI) and impervious surface configuration. In terms of the RTE, the sub-high land surface temperature (LST) zones were aggregated in a large and compact patch in central and northern BTH. However, the sub-high zones of the cities in Boswash were relatively separate. Moreover, the land development pattern of Boswash showed a stronger relationship with the RTE than that of BTH did. Global Moran's I between the LDI and LST in Boswash was higher than that in BTH. In addition, the correlation between impervious surface configuration and LST in Boswash was stronger than that in BTH, and this correlation was more controlled by LDI in Boswash. This study also indicated that BTH should change the land development pattern to prevent the further expansion of aggregated sub-high LST zones and control the proximity of high LST zones in cities in central and southern BTH, however, Boswash should adopt some local heat management approaches (installing cool and green roofs and creating more green space) in the core areas to help reduce the very high temperatures in the already highly developed areas where the largest fraction of people live.

Rapeseed is one of the major oil crops in China and it is very sensitive to climate change. The Yangtze River Basin is the main rapeseed production area in China. Therefore, a better understanding of the impact of climate change on rapeseed production in the basin is of both scientific and practical importance to Chinese oil industry and food security. In this study, based on climate data from 5 General Circulation Models (GCMs) with 4 representative concentration pathways (RCPs) in 2011–2040 (2020s), 2041–2070 (2050s) and 2071–2100 (2080s), we assessed the changes in rapeseed production potential between the baseline climatology of 1981–2010 and the future climatology of the 2020s, 2050s, and 2080s, respectively. The key modelling tool – the AEZ model – was updated and validated based on the observation records of 10 representative sites in the basin. Our simulations revealed that: (1) the uncertainty of the impact of climate change on rapeseed production increases with time; (2) in the middle of this century (2050s), total rapeseed production would increase significantly; (3) the average production potential increase in the 2050s for the upper, middle and lower reaches of the Yangtze River Basin is 0.939, 1.639 and 0.339 million tons respectively; (4) areas showing most significant increases in production include southern Shaanxi, central and eastern Hubei, northern Hunan, central Anhui and eastern Jiangsu.

The maintenance and improvement of ecosystem services on the Tibet Plateau are critical for national ecological security in China and are core objectives of ecological conservation in this region. In this paper, ecosystem service benefits of the Tibet Ecological Conservation Project were comprehensively assessed by estimating and mapping the spatiotemporal variation patterns of critical ecosystem services on the Tibet Plateau from 2000 to 2015. Furthermore, we linked the benefit assessment to the sustainable spatial planning of future ecological conservation strategies. Comparing the 8 years before and after the project, the water retention and carbon sink services of the forest, grassland and wetland ecosystems were slightly increased after the project, and the ecosystem sand fixation service has been steadily enhanced. The increasing forage supply service of grassland significantly reduced the grassland carrying pressure and eased the conflict between grassland and livestock. However, enhanced rainfall erosivity occurred due to increased rainfall, and root-layer soils could not recover in a short period of time, both factors have led to a decline in soil conservation service. The warm and humid climate is beneficial for the restoration of ecosystems on the Tibet Plateau, and the implementation of the Tibet Ecological Conservation Project has had a positive effect on the local improvement of ecosystem services. A new spatial planning strategy for ecological conservation was introduced and aims to establish a comprehensive, nationwide system to protect important natural ecosystems and wildlife, and to promote the sustainable use of natural resources.

The impact of changes in cultivated land on the production potential of food crops in China during the period of 1990–2010 was studied using land use data and the Global Agro-ecological Zones (GAEZ) model. The contribution of crop production potential per unit cultivated land area (PPCLA) to the total food-energy based production potential (TPP) of food crops was further investigated. From 1990 to 2010, China has experienced a net increase of cultivated land, resulting from a net increase in northern China and a smaller net decrease in the south. However, the TPP reduced by 9.64 × 1012 kcal despite an overall cultivated land increase for crops. This was attributed to the spatial heterogeneity of PPCLA in the cultivated land, whereby the average PPCLA of the newly cultivated land was much lower than that of the lost land. The PPCLA gap between the newly developed land and the lost cultivated land expanded from 3.16 × 106 kcal/ha in the first decade (1990–2000) to 6.49 × 106 kcal/ha in 2000–2010. Contributions of PPCLA to TPP varied among regions, and the regions with the largest contributions were consistent with those with the largest PPCLA gaps. Such regions included the Sichuan Basin and surrounding region in 1990–2000, and the Huang-Huai-Hai Plain during 2000–2010. Based on these research findings, key implications for land use policies in relation to major food crops in China are discussed.

It is crucial to assess the effects of urban expansion on croplands to allow sustainable urbanization and cropland supply. However, owing to the complexity of land conversion and various land policies in China, it is difficult to quantify the cropland dynamics and implications of urban expansion throughout the whole accelerated stage of urbanization. This study was based on land use data from 1990 to 2015 and urban expansion data from 2000 to 2030, analyzing urban expansion and predicting its impact on croplands. We found that urban area would continue to increase and croplands would contribute more than 70% of the urban expansion area. The urban area in China will likely reach 71.6&ndash, 87.0 thousand km2 or more by 2030. Although the overall area of croplands may remain at a similar magnitude in future decades, our findings imply that croplands will tend to shift northward, resulting in some potential challenges owing to resource limitations in northern regions. Our study provides a new perspective in terms of assessing future cropland dynamics and the effects of urban expansion and highlights the significance of ensuring a realistic land policy in the future.

The combination model of cellular automata and multi-agent system were used in this paper for simulating spatio-temporal dynamics of urban expansion and its encroachment on other lands at the regional scale. The human system(contain authorities and residents) and their behavior, the landscape system and its behavior as well as the inter actions between them were all simulated in this paper. The behavior of human system is established based on multi-agent system, the authority agent and the resident agent were both regarded as abstract entities. The cellular automata is embedded into the model for simulating the spontaneous urban growth. The impact of neighbor cells were considered so that the expansion of urban lands can be limited near the existed urban lands. Moreover, the rural residential lands have higher probability to convert to urban lands if they were close to the cities or towns. Simulation of urban expansion is undertaken on the time series from 2000 to 2020 for Tianjin metropolitan region, the largest open coastal city in northern China. The results show that Tianjin’s urban lands focus on the epitaxial expansion around the central city accompanied with the growing exurb expansion distributing in multiple districts and counties. The croplands are taken the most area of the land-use types, 1764.03 km2 are converted to urban lands, and more than one fourth of the rural residential lands are changed to urban lands in 2000–2020. The urban development and the cropland protection should be both taken into account to minimize the threats on food security and ecological environment.

The downstream plain of the Yellow River is experiencing some of the most severe groundwater depletion in China. Although the Chinese government has issued policies to ensure that the Yellow River can provide enough irrigation waters for this region, groundwater levels continue to decrease. Yucheng City was selected as a case study. A new method was designed to classify the cropland into various irrigated cropland. Subsequently, we analyzed data regarding these irrigated-cropland categories, irrigation norms, and the minimum amount of irrigation water being applied to cropland. The results showed that 91.5% of farmland can be classified as double irrigated (by both canal/river and well water), while 8.5% of farmland can be classified as well irrigated. During the irrigation season, the sediments brought in by the river have blocked portions of the canals. This has led to 23% of the double-irrigated cropland being irrigated by groundwater, and it is thus a main factor causing reductions in groundwater supply. These blocked canals should be dredged by local governments to mitigate local groundwater depletion. The method for classifying irrigated cropland from high-resolution images is valid and it can be used in other irrigated areas with a declining groundwater table for the sustainable use of groundwater resources.

The Three-River Headwaters region (TRHR) of China is an important part of the Qinghai-Tibetan Plateau. Although the TRHR is rich in grassland resources, the ecosystem of this area is extremely fragile. Natural and artificial interference have been key to the development of grassland ecosystem spatiotemporal heterogeneity, although the intensity and mode of their influence on ecological processes varies depending on scale; analyses in this area are therefore also scale-dependent. We use multi-scale nested data to analyze the mechanisms underlying the influence of climate change and human activities on grassland net primary productivity (NPP) by applying a multi-level modeling approach. The results of this study show that: (1) The annual grassland NPP of the TRHR has risen in a wavelike pattern over time, increasing by 39.88% overall; (2) Differences of 54.9% and 41.1% in temporal grassland NPP can be attributed to variations between these watersheds as well as county characteristics, and; (3) Although the ‘warm and moist’ climate trend seen over the course of this study has proved beneficial in enhancing grassland NPP, the rate of increase has tended to be faster in relatively dry and warm regions. Economic development and population growth have both exerted negative impacts on grassland NPP.

China is one of the countries that have been continuously experiencing negative impacts by typhoons. Typhoons cause severe damage annually, not only to the regional economy, but they are also responsible for frequent human casualties. This research comprehensively assesses the impact of typhoons across China by using the geographical information system based on time series data between 1980 and 2012. Results indicate that typhoons affected 61 % of the total landmass of China during this timeframe with a total affected area of approximately 5.91 million km2. In addition, some coastal regions of south-east China experienced nearly 300 typhoon landfalls. The key entities of this study that are used to assess typhoon risk across China include population, gross domestic production, road networks and land use. As a result, the vulnerabilities of each entity in the typhoon-affected region of China were calculated before leading to the regional typhoon risk indexes. Based on the range of typhoon risk indexes, the typhoon-affected areas in China were zoned into four regions with different levels of typhoon risk. This research will facilitate decision-making by policy makers on the mitigation of typhoon risks.

Rapid urbanization in China has raised great concerns regarding food security caused by conversion of limited cultivated land to urban use. In this study, the loss of potential crop yield due to urban expansion in China during 1990–2010 was calculated by the Global Agro-Ecological Zones (GAEZ) model. Over this period, potential yield decreased by approximately 34.90 million tons due to urban expansion, accounting for 6.52 % of China’s total actual production. The decrease was 13.07 and 21.83 million tons during the first and second decade, respectively. Key areas of lost potential yield were primarily in the Middle-lower Yangtze Plain and the Huang-Huai-Hai Plain. However, South China became a new key area of lost potential yield during the second decade. These findings provide useful information for the development of land use policy, protection of suitable arable land resources and urban development plans in China.

The quantity and spatial pattern of farmland has changed in China, which has led to a major change in the production potential under the influence of the national project of ecological environmental protection and rapid economic growth during 1990–2010. In this study, the production potential in China was calculated based on meteorological, terrain elevation, soil and land-use data from 1990, 2000 and 2010 using the Global Agro-ecological Zones model. Then, changes in the production potential in response to farmland changes from 1990 to 2010 were subsequently analyzed. The main conclusions were the following. First, the total production potential was 1.055 billion tons in China in 2010. Moreover, the average production potential was 7614 kg/ha and showed tremendous heterogeneity in spatial pattern. Total production in eastern China was high, whereas that in northwestern China was low. The regions with high per unit production potential were mainly distributed over southern China and the middle and lower reaches of the Yangtze River. Second, the obvious spatiotemporal heterogeneity in farmland changes from 1990 to 2010 had a significant influence on the production potential in China. The total production potential decreased in southern China and increased in northern China. Furthermore, the center of growth of the production potential moved gradually from northeastern China to northwestern China. The net decrease in the production potential was 2.97 million tons, which occupied 0.29% of the national total actual production in 2010. Third, obvious differences in the production potential in response to farmland changes from 1990 to 2000 and from 2000 to 2010 were detected. The net increase in the production potential during the first decade was 10.11 million tons and mainly distributed in the Northeast China Plain and the arid and semi-arid regions of northern China. The net decrease in the production potential during the next decade was 13.08 million tons and primarily distributed in the middle and lower reaches of the Yangtze River region and the Huang-Huai-Hai Plain. In general, the reason for the increase in the production potential during the past two decades might be due to the reclamation of grasslands, woodlands and unused land, and the reason for the decrease in the production potential might be urbanization that occupied the farmland and Green for Grain Project, which returned farmland to forests and grasslands.

Terrain, an important limiting factor in land use change, strongly influences agricultural productivity. This study investigated the topographical characteristics of agricultural potential productivity of cropland transformations in China during the first decade of the 21st century, and explored the impacts of cropland transformations with different terrains on agricultural potential productivity as it relates to China’s national food supply. The results showed the production potential of cropland loss was much greater than that of cropland gain in most regions, and topographical characteristics of croplands losses and gains actually impacted the agricultural potential productivity in China. The losses in agricultural potential productivity was serious in regions with good terrain conditions, where the slope is lower than 5°, and the elevation is below 100 m, especially in the middle and lower Yangtze region and the Huang-Huai-Hai region. The situation for cropland loss with better quality, and expanded the worse was severe in China, and this is expected to negatively influence sustainable agricultural development in the future. This study suggests that researchers focus not only on the total area of expanded cropland but also on cropland quality, such as the different terrain conditions of the croplands, to avoid a loss in national agricultural productivity caused by the process of cropland transformation.

Based on topographic maps and remote sensing imageries measured or captured at time instants varied from 1940s to 2012, mainland coastline in 1940s, 1960s, 1990, 2000, 2010 and 2012 in China were delineated and classified into eight types according to the differences in anthropogenic utilization. And the index of coastline utilization degree (ICUD) was defined and calculated for mainland coastline at national, provincial and local scales respectively. It turned out that, 1) over the last 70 years, especially during the last two decades in China, the ICUD increased continuously and dramatically, which shows that the impacts of human beings on mainland coastline increased incessantly. 2) Significant spatial patterns and temporal variations of the ICUD could be observed, in specific, the Yangtze River delta had much higher ICUD in the early stages; however the ICUD in the Pearl River delta and Circum Bohai Bay increased more dramatically than the Yangtze River delta in the last two decades. 3) At national and provincial scales, the intensive and accelerated exploitation of coastline, following the continual decrease of natural coastline over the last 70 years had determined the temporal trends of ICUD. However, the spatio-temporal patterns of ICUD exhibited much complicated characteristics at local scale because both human activities and physical factors had significant impacts on coastline changes. 4) Overall, the ICUD effectively revealed the spatio-temporal characteristics of mainland coastline changes and impacts of human activities on coastline in China. It will be helpful for China's ICZM decision makings to monitor the mainland coastline changes and analyze its dynamics by ICUD. (C) 2014 Elsevier Ltd. All rights reserved.

Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with standard procedures based on Landsat TM\ETM+ im- ages. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics, differences, and causes of land-use changes at a national scale were then examined. The main findings are summarized as fol- lows. Land-use changes (LUCs) across China indicated a significant variation in spatial and temporal characteristics in the last 20 years (1990-2010). The area of cropland change de- creased in the south and increased in the north, but the total area remained almost un- changed. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly, were mainly distributed in the east, and gradually spread out to central and western China. Woodland decreased first, and then increased, but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the

Maritime networks are one of the most important types of transportation networks in international logistics and it accounts for 90% of the global trade volume. However, the structure of maritime networks is severely impacted by tropical cyclones, especially the maritime network in the Northwest Pacific and the northern Indian Ocean. This paper investigates the vulnerability of the maritime network in the Northwest Pacific and the northern Indian Ocean to the influence of tropical cyclones through removing ports at high or very high tropical cyclones hazard levels and analyzing how the network structure characteristics change from a complex network point of view. From the results, we find that this maritime network is a small-world network and the degree distribution of ports follows a power law distribution. The ports in East Asia are impacted more severely by the tropical cyclones. Moreover, this maritime network exhibits some vulnerability to tropical cyclones. However, the interconnection of the survived ports is not severely impacted, when the network is attacked by tropical cyclones. The port system in the Philippines is most vulnerable to the influence of tropical cyclones, followed by the ports systems in Japan and China. The paper also shows that it is important for studies of maritime network vulnerability to identify the ports that are both important to the regional and cross-regional logistics and severely impacted by natural hazards. The findings provide a theoretical basis for optimizing the port layout and improving the ability of the network to resist damage caused by tropical cyclones.

China possesses substantial biomass resources, and the cultivation of energy plants on marginal land and the advancement of bioenergy may prove beneficial in easing fossil-fuel energy demands and promoting sustainable development of the economy and the environment. Taking into account the availability of marginal land and the distribution of environments suitable for the cultivation of energy crops, this study provides estimates of the potential bioenergy production for each of five species (Pistacia chinensis, Jatropha curcas, Manihot esculenta, Vernicia fordii and Helianthus tuberosus) and a geographic analysis of bioenergy enterprises in China. The results support the following conclusions: (1) the geographic distributions of potential bioenergy output of various energy crops have significant differences; (2) the central regions of China between Yunnan and Heilongjiang are suitable for the development of large- and medium-sized enterprises, whereas the area spanning northern Xinjiang, central Inner Mongolia, northern Yunnan, central Sichuan, eastern Guangdong and Hunan may support small-scale bioenergy enterprises; (3) the potential for development of bioenergy enterprises in China is enormous, the total number of bioenergy enterprises that are sustainable in China is 1788 (of which 490 are small-scale, 629 are medium-scale and 669 are large-scale operations); (4) the provinces with the greatest potential for the development of large-scale enterprises are Yunnan, Guizhou, Shaanxi, Hubei and Heilongjiang.

Characterization of spatiotemporal variation of water quality is a basic environmental issue with implications for public health in China. Trends in the temporal and spatial distribution of water quality in the Huai River System (HRS) were analyzed using yearly surface water quality data collected from 1982 to 2009. Results showed that the water quality of the main stream deteriorated in the 1990s and early 2000s but has been ameliorated since 2005. The sections that were classified as severely polluted from the monitoring data were located largely in the middle reach. The water quality of HRS fluctuated during the period 1997–2009; it has improved and stabilized since 2005. In terms of spatialized frequency of serious pollution, heavily polluted regions were mostly concentrated in the area along several tributaries of the Ying, Guo and New Sui Rivers as well as the area north of Nansi Lake. These regions decreased from 1997 to 2009, especially after 2005. Our analysis indicated that water pollution in HRS had a close relation with population and primary industry during the period 1997–2009, and implied that spatiotemporal variation of surface water quality could provide a scientific foundation for human health risk assessment of the Huai River Basin.

From early November 2008 to February 2009, lack of rainfall led to severe drought in northern China. More than 9.3 million ha of wheat in six major crop production provinces, including Henan, Anhui, Shandong, Shanxi, Gansu, and Shaanxi, were hit by drought. Supported by Chinese HJ-1 satellite images together with NASA Moderate Resolution Imaging Spectroradiometer (MODIS) data, dynamic monitoring of the drought was conducted. HJ-1 CCD data with 30-m resolution were used to identify cropland information. Spatial–temporal variation of drought was detected using Vegetation Index and Water Index time series data derived from MODIS visible, infrared, and short-wave infrared bands. The influences of drought were classified into five levels based on MODIS-derived 8-day composite Anomaly Water Index (AWI) and field survey data. The results indicated that the drought deteriorated beginning in November 2008 and became most serious in late January 2009. HJ-1 data together with MODIS data proved to be valuable data sources for monitoring soil moisture and drought at a both regional and national scale.

Understanding the influence of temperature on hand-foot-and-mouth disease (HFMD) is an important public health concern as well as being a major climate-infection issue in mainland China. City-scale data of incidence rates (IRs) of HFMD and temperature from 2008 to 2009 in mainland China has been analyzed. There were two peak periods for HFMD prevalence from April to July and August to November. Regions with higher monthly IR of HFMD periodically shifted following the pattern of south-north-south from March to December. Monthly IR of HFMD at city scale were closely associated with both average monthly temperature and monthly temperature range. Our study shows that spatiotemporal trends of HFMD infection were sensitive to temperature variation, and suggest that preventive measures should be considered for limiting the epidemic of HFMD in the cities with higher monthly IR during the peak periods.

China has abundant crop residues (CRE) that could be used for bioenergy. The spatiotemporal characteristics of bioenergy production are crucial for high-efficiency use and appropriate management of bioenergy enterprises. In this study, statistical and remote-sensing data on crop yield in China were used to estimate CRE and to analyze its spatiotemporal changes between 1990 and 2010. In 2010, China’s CRE was estimated to be approximately 133.24 Mt, and it was abundant in North and Northeast China, the middle and lower reaches of the Yangtze River, and South China, CRE was scarce on the Loess and Qinghai–Tibet Plateaus. The quantity of CRE increased clearly over the 20-year analysis period, mainly from an increase in residues produced on dry land. Changes in cultivated land use clearly influenced the changes in CRE. The expansion of cultivated land, which mainly occurred in Northeast and Northwest China, increased CRE by 5.18 Mt. The loss of cultivated land, which occurred primarily in North China and the middle and lower reaches of the Yangtze River, reduced CRE by 3.55 Mt. Additionally, the interconversion of paddy fields and dry land, which occurred mostly in Northeast China, increased CRE by 0.78 Mt. The findings of this article provide important information for policy makers in formulating plans and policies for crop-residue-based bioenergy development in China, and also for commercial ventures in deciding on locations and production schedules for generation of bioenergy.

Urbanization is a global problem with demographic trends. The urban heat island plays a dominant role in local climate systems. Despite existing efforts to understand the impacts of multiple urbanization factors on the urban heat island globally, very little is known about the attribution of urban heat island magnitude to urbanization in different locations or developmental phases. In this study, based on global land surface temperature data, urban spatial domain data, gross domestic product (GDP), and population data, we analyzed the influence of multiple urbanization factors on global surface urban heat island intensity (SUHII). We also tentatively compared the abovementioned factors between different regions across the globe, especially between China and the USA, the largest countries that are experiencing or have experienced rapid urbanization in recent decades. The results showed that global SUHII had remarkable spatial heterogeneity due to the geographical and socioeconomic variation between cities. There was a significant correlation between SUHII and population as well as GDP in global cities. Moreover, this study suggested that the impacts of population on SUHII might be stronger in the early stages of urbanization, and the GDP factor would become a critical factor at a certain development level. The urban area also had non-ignorable impacts on SUHII, while the correlation between SUHII and urban shape was relatively weak. All these may imply that the best approach to slow down SUHII is to find other solutions, e.g., optimize the spatial configuration of urban internal landscapes, when the urbanization reaches a high level.

The Qin-Ba Ecological Functional Zone is a component of China’s ecological security pattern designed to protect the regional ecosystem and maintain biodiversity. However, due to the impact of mining and urban encroachment, the plight of a sustainable ecosystem in the Qin-Ba mountainous area is deteriorating. This paper has used a remote sensing and geographic information system (GIS) to examine the impacts of mining and urban encroachment on the environment in the Qin-Ba mountainous area. The results indicate that the total mined area in 2013 was 22 km2 and is predicted to escalate. Results also show that the ecosystems in Fengxian County, Shaanxi Province and Baokang County, Hubei Province were most severely affected by mining. Urbanization in the Qin-Ba mountainous area has seen an increase of 85.58 km2 in urban land use from 2010 to 2013. In addition, infrastructure development including airport construction, tourism resorts and real estate development in the Qin-Ba mountainous area has intensified environmental and biodiversity disturbances since large areas of forest have been cleared. Our results should provide insight and assistance to city planners and government officials in making informed decisions.

The planted forest area and carbon sequestration have increased significantly in China, because of large-scale reforestation and afforestation in the past decades. In this study, we developed an age-based volume-to-biomass method to estimate the carbon storage by planted forests in China in the period of 1973–2003 based on the data from 1209 field plots and national forest inventories. The results show that the total carbon storage of planted forests was 0.7743 Pg C in 1999–2003, increased by 3.08 times since the early 1970s. The carbon density of planted forests varied from 10.6594 Mg/ha to 23.9760 Mg/ha and increased by 13.3166 Mg/ha from 1973–1976 to 1999–2003. Since the early 1970s, the planted forests in China have been always a carbon sink, and the annual rate of carbon sequestration was 0.0217 Pg C/yr. The carbon storage and densities of planted forests varied greatly in space and time. The carbon storage of Middle South China was in the lead in all regions, which accounted for 23%–36% of national carbon storage. While higher C densities (from 17.79 Mg/ha to 26.05 Mg/ha) were usually found in Northeast China. The planted forests in China potentially have a high carbon sequestration since a large part of them are becoming mature and afforestation continues to grow.

National Key Programme for Developing Basic Science [2009CB421105]; Chinese Academy of Sciences [KSCX1-YW-09-01]

Using meteorological data and RS dynamic land-use observation data set, the potential land productivity that is limited by solar radiation and temperature is estimated and the impacts of recent LUCC processes on it are analyzed in this paper. The results show that the influence of LUCC processes on potential land productivity change has extensive and unbalanced characteristics. It generally reduces the productivity in South China and increases it in North China, and the overall effect is increasing the total productivity by 26.22 million tons. The farmland reclamation and original farmlands losses are the primary causes that led potential land productivity to change. The reclamation mostly distributed in arable-pasture and arable-forest transitional zones and oasises in northwestern China has made total productivity increase by 83.35 million tons, accounting for 3.50% of the overall output. The losses of original farmlands driven by built-up areas invading and occupying arable land are mostly distributed in the regions which have rapid economic development, e.g. Huang-Huai-Hai plain, Yangtze River delta, Zhujiang delta, central part of Gansu, southeast coastal region, southeast of Sichuan Basin and Urumqi-Shihezi. It has led the total productivity to decrease 57.13 million tons, which is 2.40% of the overall output.

The Three-Rivers Headwaters region (TRHR) is an ecological shelter located in the northeast of the Tibetan Plateau, China, that provides environmental protection and regional sustainable development. This region also provides ecosystem services including water supply and soil conservation and exerts major impacts on both its surroundings, as well as the whole of China. A number of ecological restoration projects have been initiated within the TRHR since 2000, including the creation of a natural reserve. Analyses of trends in land use/land cover (LULC), net primary productivity (NPP), water yield and soil conservation within the TRHR are presented based on regional climate and land use datasets and utilizing the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model in tandem with the double mass curve (DMC) approach. The results of this study reveal a series of correlations between ecosystem services and lead to four distinct conclusions. First, the amount of variation between 2000 and 2012 in each LULC type within the TRHR was small. In particular, grassland substitution occurred in high-altitude areas and increased in central areas. Second, NPP, water yield, soil conservation amount and the volume of exported phosphorus (P) decreased along an east-west gradient with values of 64.44%, 38.81%, 7.37% and −49.98% recorded, respectively, between 2000 and 2012. The ecosystem services of the Yellow River basin to the east of the TRHR generally improved over the study period, while those of the Yangtze River and Lancang River basins where enhanced to a lesser extent, and obvious degradation was observed in some local areas. Third, the ecosystem services provided by forested land were highest, followed by grassland and cultivated land, respectively. Fourth, synergistic relationships were observed within the TRHR between NPP, water yield and soil conservation amount, indicating that increasing NPP simultaneously increased the values for these related factors. Synergistic relationships were also recorded between water yield and the amount of exported P, suggesting that increases in the former cause a reduction in water purity.

Hemorrhagic fever with renal syndrome (HFRS) is an important public health problem in China. The identification of the spatiotemporal pattern of HFRS will provide a foundation for the effective control of the disease. Based on the incidence of HFRS, as well as environmental factors, and social-economic factors of China from 2005–2012, this paper identified the spatiotemporal characteristics of HFRS distribution and the factors that impact this distribution. The results indicate that the spatial distribution of HFRS had a significant, positive spatial correlation. The spatiotemporal heterogeneity was affected by the temperature, precipitation, humidity, NDVI of January, NDVI of August for the previous year, land use, and elevation in 2005–2009. However, these factors did not explain the spatiotemporal heterogeneity of HFRS incidences in 2010–2012. Spatiotemporal heterogeneity of provincial HFRS incidences and its relation to environmental factors would provide valuable information for hygiene authorities to design and implement effective measures for the prevention and control of HFRS in China.

Atmospheric pollution has become a significant challenge in Beijing metropolitan region, China. In this study, wavelet analysis and gray analysis were proposed to explore the temporal characteristics of particulate matter (PM10) and its relationships with meteorological factors during 2001-2012. The analysis indicated that air quality had got better significantly over the last decade. It was clearly interannual, seasonal, and monthly variation of atmospheric pollution, which represented that the air quality was the worst in spring, and got better in summer, subsequently tended to be more serious in autumn and winter. Generally atmospheric pressure was the most important meteorological feature influencing on PM10, followed by relative humidity and wind speed. However, the dominant meteorological factors influencing the atmospheric pollution were different in the four seasons. The results suggest that urban design and effective measures based on the relationship between meteorological factors and PM10 would be effective for improving atmospheric pollution.

From the Global Agro-Ecological Zone (GAEZ) model, changes in the three climate factors (temperature, precipitation, and solar radiation) over the past five decades showed different trends and that production potential was impacted significantly by the geographic heterogeneity of climate change. An increase of approximately 1.58 million tons/decade in production potential correlated with climate change. Regions with increased production potential were located mainly in the Northeast China Plain, the northern arid and semiarid region, and the Huang-Huai-Hai Plain. Regions with decreased production potential were located mainly in the Middle-lower Yangtze Plain and southern China. The climate factors that impacted production potential varied by region. In the Northeast China Plain, increased temperature was the major cause of the increased production potential. In the northern arid and semiarid region, temperature and precipitation were the major factors affecting production potential, but their effects were in opposition to each other. In southern China, increased temperature and decreased solar radiation caused a decreased production potential. In the Middle-lower Yangtze Plain, a decrease in solar radiation was the major factor resulting in decreased production potential. In the Huang-Huai-Hai Plain, changes in temperature and solar radiation had large but opposite effects on production potential.

China policies and Grain-for-Green Project have led to changes in farmland area and grain production. Climate change was also occurring during this period. To analyze the effects of land use and climate change on grain production, the area of farmland in northern China during 1988–2008 was determined from remote sensing images, a moisture index (MI) was calculated from daily meteorological data obtained from weather stations, and unit grain production was obtained from statistical yearbooks. Using statistical and spatial analyses, we determined that MI decreased across most of the study area during this period. This decrease in humidity caused humid zones to decrease and semiarid areas to increase. Combined effects of decreased humid area and conversion of farmland resulted in a decrease in agricultural land in humid areas and an increase in semiarid and arid areas. Increases in unit grain production, machine power, and irrigated farmland area led grain production to increase from 122,799,081 to 188,532,597 ton in humid areas, from 28,875,900 to 115,976,814 in semiarid areas, and from 7,622,100 to 15,490,026 in arid areas, respectively. Increased unit grain production and farmland resulted in increased importance of semiarid areas for grain production.

Rapid urbanization and population growth in China have raised great concerns regarding food security caused by the loss of limited cultivated land. In this study, we used remotely sensed data and an agricultural productivity estimation model to characterize the spatiotemporal patterns of the conversion of cropland into urban land and quantify its impacts on agricultural productivity potential during China’s rapid urbanization period, from 1990 to 2010. The results show that urban development has transformed approximately 4.18 Mha, or 2.26%, of the total cropland in China. From 1990 to 2000, approximately 1.50 Mha of cropland was developed, while roughly 1.8 times this amount (2.68 Mha) was converted over the period of 2000 to 2010. Most of the conversion is located in the central and eastern coastal provinces and is mainly concentrated on the periphery of the major urban areas. The transformation has, consequently, caused a 71.45 Tg, or 2.65%, loss of potential light-temperature agricultural productivity (PLTAP); losses were 24.33 Tg in the first decade of the study and 47.11 Tg in the second. At the provincial scale, the largest percentages of PLTAP loss are mainly concentrated in the developed provinces on the eastern coast, such as Shanghai, Beijing, Zhejiang, Tianjin, and Jiangsu. Considering that these areas can accommodate more people and produce higher economic output on unit area of built-up land and, yet, scarce land that can be reclaimed, this study suggests that the dynamic balance of total farmland policy in China should be varied provincially according to the major function of the province. The policy adjustment will help maximize the utilization efficiency of land.

The multiple cropping practice is essential to agriculture because it has been shown to significantly increase the grain yield and promote agricultural economic development. In this study, potential multiple cropping systems in China are calculated based on meteorological observation data by using the Agricultural Ecology Zone (AEZ) model. Following this, the changes in the potential cropping systems in response to climate change between the 1960s and the 2010s were subsequently analyzed. The results indicate that the changes of potential multiple cropping systems show tremendous heterogeneity in respect to the spatial pattern in China. A key finding is that the magnitude of change of the potential cropping systems showed a pattern of increase both from northern China to southern China and from western China to eastern China. Furthermore, the area found to be suitable only for single cropping decreased, while the area suitable for triple cropping increased significantly from the 1960s to the 2000s. During the studied period, the potential multiple cropping index (PMCI) gap between rain-fed and irrigated scenarios increased from 18% to 24%, which indicated noticeable growth of water supply limitations under the rain-fed scenario. The most significant finding of this research was that from the 1960s to the 2000s climate change had led to a significant increase of PMCI by 13% under irrigated scenario and 7% under rain-fed scenario across the whole of China. Furthermore, the growth of the annual mean temperature is identified as the main reason underlying the increase of PMCI. It has also been noticed that across China the changes of potential multiple cropping systems under climate change were different from region to region.

climatic resource is a primary condition of determining agricultural development of area. This paper regards land use pattern as the unit of calculating, utilize the meteorological materials day by day of 1991-2000 year, and estimates the impact of recent climate fluctuation on potential productivity for crops in Northeast China. The result shows: because the climate has become warm in Northeast crop growing period in the past 10 years (The temperature has increased 2.19 degrees C and the annual precipitation decreased 305.76mm), the crop potential productivity generally reduced by 6.45%. Moreover, the change of the precipitation is the main reason causing the different trends of crop potential productivity in different area.

Northeast China is the national commercial grain base of China. It provides the critical food supply for other areas of the country every year. In this region dramatic changes, such as population increase, deforestation, grass land degeneration, wetland shrinking and so on, have taken place in recent several decades. The changes in resources and environment in this region have significant impacts on human living, social economy and many other aspects of the regional development. In this study uses Remote Sensing (RS), GIS and other information technology to reconstruct a digital Northeast China of the last 100 years from year 1900 to 2000. This paper first introduces the Digital Northeast China of this 100 years which includes the system targets, data foundation and design frame. Then as a case study, the woodland resource changes after 1980s based on the completed dataset are analyzed. This Digital Northeast China is based on satellite remote sensing images (Landsat TM and ETM) and topology maps and can help people solve problems related to population, natural resources and environment. On the other hand, the Digital Northeast China system can help farmers make wise use of land, increase production and preserve environment simultaneously. Furthermore, using data contained in the system, geographical scientists can analyze the resource and environment changes and make certain forecasts of the future development.

During the past 20 years, China's agro-ecosystems have great changes in response to changes in climate and agricultural management. Agricultural productivity is of vital importance to the national food security and sustainable development. So far, agricultural statistics are the only source of the data about changes in agricultural productivity in national scale, and there is little geo-spatial information on these changes. Remote sensing provides an important tool to monitor the spatial and temporal variations at high resolution, but it had yet to be used fully at regional and national scales to assess the interannual and long-term changes in agricultural productivity. This study estimated agricultural net primary productivity (ANPP) at the national level using a remote sensing-based production efficiency model, GLO-PEM. In the study, the arable area has been derived from TM data. ANPP was calculated from 8km, 10-day composite Advanced Very High Resolution Radiometers (AVHRR) data from 1981 to 2000 using GLO-PEM model. Using the data we analyzed the spatial variations in agricultural productivity in China between the 1980s and the 1990s. A 3-level hierarchy regionalization system is used in analyzing the spatial pattern and its changes in the agricultural productivity. China's average agricultural ANPP increased 59.8 million tons from the 1980s to the 1990s. The increment of ANPP mainly occurred in the major cereal-planting plains, especially HuangHuaiHai Plain. The characteristics of land resources are the dominating factors to cause the changes at 10 years scale. There were some decreases, which mainly caused by the degradation on fragile lands, the rapid expansion of rural industries, and the urban development from high-quality arable lands.

Land-Use/Land-Cover Change (LUCC) affects farmland productivity by changing the quality of land resource and pattern of land-use. Based on meteorological data and land-use/cover observation dataset obtained from the dynamic serving system of National Resources and Environment Database (NRED), this paper calculated the Photosynthetic Thermal Productivity (PTP) of farmland, and analyzed impact of recent LUCC and climate fluctuation on PTP. Results showed that under the influence of LUCC, PTP distribution had an extensive and unbalanced change. LUCC increased China's total PTP by 26.22 million tons, while climate fluctuation increased it by 169.92 million tons. The ratio between LUCC and climate fluctuation was 1:6.48. Due to the direct effect of LUCC, PTP increased in the following regions: Northeastern Plain, Inner Mongolia, and Xinjiang province. This increase was primarily driven by plantation reclamation. PTP decreased in the Huang-Huai-Hai Plain, the Yangtse Rive delta, the Zhujiang delta, the Southeastern coastal provinces, the southeastern Sichuan basin and the Xinjiang oasis. The decrease was mainly caused by urban expansion.

Land cover data represent a fundamental data source for various types of scientific research. The classification of land cover based on satellite data is a challenging task, and an efficient classification method is needed. In this study, an automatic scheme is proposed for the classification of land use using multispectral remote sensing images based on change detection and a semi-supervised classifier. The satellite image can be automatically classified using only the prior land cover map and existing images; therefore human involvement is reduced to a minimum, ensuring the operability of the method. The method was tested in the Qingpu District of Shanghai, China. Using Environment Satellite 1(HJ-1) images of 2009 with 30 m spatial resolution, the areas were classified into five main types of land cover based on previous land cover data and spectral features. The results agreed on validation of land cover maps well with a Kappa value of 0.79 and statistical area biases in proportion less than 6%. This study proposed a simple semi-automatic approach for land cover classification by using prior maps with satisfied accuracy, which integrated the accuracy of visual interpretation and performance of automatic classification methods. The method can be used for land cover mapping in areas lacking ground reference information or identifying rapid variation of land cover regions (such as rapid urbanization) with convenience.

We found that formula (1) was incorrect in our paper published in Sensors in 2008 [1]. [...]