Global food security is increasingly threatened by climate change and regional human conflicts. A... more Global food security is increasingly threatened by climate change and regional human conflicts. Abnormal fluctuations in crop production in major exporting countries can cause volatility in food prices and household consumption in importing countries. Here we show that timely forecasting of crop harvest from satellite data over major exporting regions can trigger production response in the opposite hemisphere to offset the short-term fluctuations and stabilize global food supply. Satellite forecasting can reduce the fluctuation extents of country-level prices by 1.1 to 12.5 percentage points for anticipated wheat shortage or surplus in Russia and Ukraine, and even reverse the price shock in importing countries for anticipated soybean shortage in Brazil. Our research demonstrates that by leveraging the seasonal lags in crop calendars between the Northern and Southern Hemispheres, operational crop monitoring from satellite data can provide a mechanism to improve global food security.
It has been shown that the proportion of intense tropical cyclones (TCs) has been increasing toge... more It has been shown that the proportion of intense tropical cyclones (TCs) has been increasing together with a poleward migration of TC track. However, their relative importance to TC surge at landfall remains unknown. Here we examine the sensitivity of TC surge in Shanghai to landfall location and intensity with a new dynamical modelling framework. We find a surge sensitivity of 0.8 m (°N)−1 to landfall location, and 0.1 m (m s−1)−1 to wind speed in Shanghai during landfall. The landfall location and intensity are comparably important to surge variation. However, based on a plausible range of reported trends of TC poleward migration and intensity, the potential surge hazard due to poleward migration is estimated to be about three times larger than that by intensity change. The long‐term surge risk in Shanghai is therefore substantially more sensitive to changes of TC track and landfall location than intensity. This may also be true elsewhere and in the future.
Toxic chemicals have severe impacts on ecosystem, climate change and human health, and the curren... more Toxic chemicals have severe impacts on ecosystem, climate change and human health, and the current toxic releases are inequitably distributed across regions. Investigating the toxic release embodied in final demand by states and income groups can reveal the responsibility transfer of different entities. In this paper, we extended the U.S. multi-regional input-output (MRIO) model with toxic chemical release data in 2017 to conduct the production-and consumption-based accounting of toxic release by each state, and the interregional transfer of embodied toxic release between states. In addition, this paper analyzed how the toxic releases and interstate transfer of embodied toxic release have been driven by income groups across states. The results showed that the toxic release from production was highly concentrated on the central states and the Great Lakes Region, while the consumption-based accounting of toxic release was more equally distributed across regions in the US. The non-metallic and metallic products manufacturing sectors were the most important sectors for most states from both production and consumption-based perspectives and were also the most essential sectors for interregional flows of embodied toxic release from Great Lake Region to Southeast, Mid-Atlantic and Northeast. Our results also showed that the largest portion (41.88%) of embodied toxic releases were triggered by households' final demand, and that the consumption of the richest 35% of households contributed to more than 50% of the total toxic chemical releases triggered by total final demand of all households.
Double-rice cropping (DRC) in southern China has made outstanding contributions to ensuring food ... more Double-rice cropping (DRC) in southern China has made outstanding contributions to ensuring food security, along with a large amount of greenhouse gas (GHG) emissions. The observed significant shift from double- to single-rice (DtS) cropping since 1990 in southern China has led to great concerns on food security, despite its contribution to GHG emissions reduction. How to ensure food security without compromising the goal of mitigating GHG emission requires innovative thinking and a comprehensive tradeoff analysis of all plausible options. This study adopts a multi-model coupling method to simulate the yield and GHG emissions trade-offs across grid-cells by incorporating the option of planting elite super rice in the DtS areas. The simulation results indicate that planting elite super rice with longer growth period in the DtS areas has the potential to compensate the annual yield loss caused by the DtS shift while significantly mitigating GHG emissions in comparison with the convent...
Global greenhouse gas (GHG) emissions can be traced to five economic sectors: energy, industry, b... more Global greenhouse gas (GHG) emissions can be traced to five economic sectors: energy, industry, buildings, transport and AFOLU (agriculture, forestry and other land uses). In this topical review, we synthesise the literature to explain recent trends in global and regional emissions in each of these sectors. To contextualise our review, we present estimates of GHG emissions trends by sector from 1990 to 2018, describing the major sources of emissions growth, stability and decline across ten global regions. Overall, the literature and data emphasise that progress towards reducing GHG emissions has been limited. The prominent global pattern is a continuation of underlying drivers with few signs of emerging limits to demand, nor of a deep shift towards the delivery of low and zero carbon services across sectors. We observe a moderate decarbonisation of energy systems in Europe and North America, driven by fuel switching and the increasing penetration of renewables. By contrast, in rapid...
Rapid economic growth and urbanization in China have led to a substantial change in consumption p... more Rapid economic growth and urbanization in China have led to a substantial change in consumption patterns and diet structure of Chinese consumers over the past few decades. A growing demand for feed, fuel and fiber also places intense pressure on land resources. With continuing growth of China's economy and migration from rural to urban, the increase in food consumption and change in diet structure will likely continue, which will not only impose pressure on domestic land resources but also exert impact on land resources in other countries through import. This article applies a global multiregion input-output (MRIO) model to trace agricultural land use along global supply chains and examines the impact of China's future food consumption on global land use in 2030 against different socioeconomic and technological scenarios. Our result shows that by 2030, China would need an additional 21% of cropland to support its increasing food demand driven by population growth, urbanization and income growth and the associated diet structure change. Almost a third of cropland associated with household consumption (34 Mha) will be "outsourced" to foreign countries, such as Argentina, Brazil, United States and Thailand, for the consumption of cereal grains, soybeans and paddy rice. China also consumes 2.4 Mha cropland from Africa for its consumption of cereal grains and oil seeds. The dependence of domestic consumption on significant amounts of foreign cropland shows that China would face serious challenges to meet its grain selfsufficiency policy in the future, and at the same time this dependence would contribute to environmental and food security problems elsewhere.
Protected areas (PAs) have been regarded as a critical strategy to protect natural forest (NF) an... more Protected areas (PAs) have been regarded as a critical strategy to protect natural forest (NF) and biodiversity. Estate-crop expansion is an important driver of deforestation in Indonesia. Yet, little is known regarding the temporal dynamics of PA effectiveness in preventing estate-crop expansion into NF. We employ Cox proportional hazard models and their extensions to characterize the dynamics of estate-crop expansion into NF in Indonesia during 1996-2015. The results show that PA effectiveness in Sumatra decreased over time and became insignificant in 2012-2015. A multistate modeling analysis shows that hopping in land-cover and land-use change (LCLUC) trajectories with shrub and/or bare ground as intermediates has decreased PA effectiveness and facilitated the expansion. Preventing LCLUC trajectory hopping becomes crucial to biodiversity conservation because it tends to occur at lowland forest, diminishing natural habitat area and increasing NF isolation. K E Y W O R D S deforestation, estate-crop expansion, Indonesia, multistate modeling, protected area This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Biofuels play a critical role in the Paris Agreement to help achieve climate change mitigation ta... more Biofuels play a critical role in the Paris Agreement to help achieve climate change mitigation targets. However, a significant increase in production of biofuels might potentially be realized at the expense of overusing natural resources, particularly land and water. Understanding the tradeoffs between the impacts on land and water arises as a critical issue in the development of biofuels. This energy-water-land nexus might be particularly important for Brazil, which currently is the world's second largest producer and the largest exporter of biofuels. Furthermore, Brazil itself has set up its own Intended Nationally Determined Contribution agenda with a significant growth of biofuel production (18%) by 2030. Most studies on environmental impacts of biofuel production have either focused on land use or water use, but very few studies assessed both. Using an environmentally extended multiregional input-output (MRIO) approach, this study analyzes the current water-land nexus of bioenergy production in Brazil by quantifying the distribution of tradeoffs and synergies between land and water use for bioethanol production and its environmental consequences across Brazilian states. Our results show a clear tradeoff of water and land impacts and significant differences between irrigated and rainfed ethanol production. When including water and land scarcity in the analysis, the results are significantly different, uncovering very different tradeoffs and synergies between bioethanol producer and consumer states that could inform the expansion of bioenergy in Brazil. Compared to other crops, sugarcane has a higher comparative advantage relative to land than to water.
Soybean is an important source of protein for humans and livestock. The steadily increasing deman... more Soybean is an important source of protein for humans and livestock. The steadily increasing demand fo soybean and global climate change both have brought great concern on risks and uncertainty in soybean supply. While fieldwork reports suggest that soybean farmers are aware of the risks posed by climate change and are adopting adaptive and mitigating measures, few studies have simulated and quantitatively assessed the effects of these adaptive techniques. In this study, we established a model coupling procedure between Decision Support System for Agrotechnology Transfer (DSSAT) and the China Agro-ecological Zone model (AEZ-China) to simulate soybean production based on observation records of soybean growth at 13 agro-meteorological observation stations in northeasten China and the Huang-Huai-Hai Plain over 1981-2011. The coupling procedure takes the advantage of DSSAT in its ability to calibrate the eco-physiological parameters based on simulating the dynamic bio-physiological processes of crop growth in daily step and the advantage of AEZ in rapidly evaluating the effects of shifts in planting day and changes in the length of growth cycle. Results indicate that climate change would result in beneficial effects in Northeastern China and cause losses in the Huang-Huai-Hai Plain in 2050s, the simulations using adaptive planting dates and cultivars with adaptive length of growth-cycle show that the losses can be reduced obviously.
It has been shown that the proportion of intense tropical cyclones (TCs) has been increasing toge... more It has been shown that the proportion of intense tropical cyclones (TCs) has been increasing together with a poleward migration of TC track. However, their relative importance to TC surge at landfall remains unknown. Here we examine the sensitivity of TC surge in Shanghai to landfall location and intensity with a new dynamical modelling framework. We find a surge sensitivity of 0.8 m (N) À1 to landfall location, and 0.1 m (m s À1) À1 to wind speed in Shanghai during landfall. The landfall location and intensity are comparably important to surge variation. However, based on a plausible range of reported trends of TC poleward migration and intensity, the potential surge hazard due to poleward migration is estimated to be about three times larger than that by intensity change. The long-term surge risk in Shanghai is therefore substantially more sensitive to changes of TC track and landfall location than intensity. This may also be true elsewhere and in the future. K E Y W O R D S climate change, landfall, storm surge, tropical cyclone 1 | INTRODUCTION Tropical cyclone (TC) related hazards pose the greatest threat to coastal regions (Pielke et al., 2008; Rappaport, 2014), especially in East Asia where the population and economy are growing rapidly and are vulnerable to natural hazards (Small and Nicholls, 2003). China has the highest rate of TC landfalls in the world (Fudeyasu and Wang, 2011), and China's coastal provinces, exposed directly to landfall TC hazards, account for more than half of China's GDP in 2019. Shanghai, the financial centre of China, is ranked as a top-10 city in the
Abstract Paddy rice cultivation is an important source of agricultural greenhouse gas emissions i... more Abstract Paddy rice cultivation is an important source of agricultural greenhouse gas emissions in China. The traditional flooded paddy rice fields not only use large amounts of irrigation water, but also produce significant methane (CH4) emissions. To balance food security with environmental impacts of rice production, many water-saving irrigations technologies have been tested in the field to increase the drainage period during the rice growth cycle. However, whether these management solutions can be implemented at the regional scale needs to be further explored. Because it is too time-consuming and resource-intensive for field experiments to be carried out across large areas, we opt to assess the regional impacts of alternative irrigation schemes via computer modeling, by coupling the well-known DSSAT and DNDC models, which have been extensively validated in China. Irrigation methods tested include the traditional Continuous Flooding (CF), Midseason Drainage (MD) and Alternate Wetting and Drying (AWD). Simulation results show that compared with CF, water-saving irrigation methods can significantly reduce the CH4 emission from paddy rice field, with slight or no loss in expected rice yields. AWD had the greatest effect in reducing irrigation water amounts and CH4 emission. Compared with CF, CH4 emission under the AWD were 60% - 71% lower in Northeast China sites and 34% - 65% lower in South China sites. At the same time, compared to CF, irrigation water use in AWD was reduced by 23% - 34% in northeast China sites and by 18% - 50% in south China sites. Our results suggest that policies that support expansion of AWD in paddy rice cultivation across China can lead to a “win-win” for the food-water-GHG emissions tradeoffs, and offer a viable solution for policy makers and stakeholders in China.
This paper presents an up-to-date survey of the comparison issue between state-owned enterprises ... more This paper presents an up-to-date survey of the comparison issue between state-owned enterprises (SOEs) and township-village enterprises (TVEs) in China. Although TVEs are at a disadvantage in areas such as technology, labor skills, education levels of staff. access to bank loans and government supports, they have important advantages in ownership and governance structures, personnel systems and labor relations, and conditions of institutional arrangement. These advantages apparently have outweighed the disadvantages, allowing the TVEs to outperform SO Es and successfully expand their market shares that previously belonged to the SOEs. However, our analysis also reveals that SOEs may not have performed so badly if their broad social contributions other than reported profits are also taken into account. Jn conclusion, we argue that both SOEs and TVEs need to reform their ownership and governance structures. Jn particular, if TVEs are to develop further during the next century, they cannot avoid the grassroots democratization.
Food and nutrition security has been a persistent major challenge to human societies and this cha... more Food and nutrition security has been a persistent major challenge to human societies and this challenge continues into the 21st century, especially taking into consideration the targets set by the UN Sustainable Development Goals, which call for eradicating hunger (goal 2), ending poverty (goal 1), sustainably managing and using natural resources and ecosystems (goal 15), and combating climate change (goal 13). The way food is consumed and produced affects the human well-being as well as the environment. Avoiding food losses and adopting a balanced healthy diet is also an important step towards sustainability. Promoting dietary standards and monitoring their adoption is a potentially important policy tool for mitigating environmental impacts of food production as well as monitoring food security and nutrition. There is relatively little research to measure nutritional adequacy of food intake according to dietary standards, and to explore the relationship with health outcomes. In this study we choose the well-established WHO global-level dietary recommendations as a reference to quantify nutritional adequacy by developing an energy and macronutrient intake index (ENI), and to assess its relation to indicators of hunger and undernutrition. We find strong negative association between nutritional adequacy of dietary intake and prevalence of undernutrition at national level, and we illustrate that ENI could be an effective tool to inform national food security strategies. Under different future socioeconomic development scenarios, almost all sub-Saharan African countries achieve an adequate per capita energy intake level but their nutritional status varies with many countries deviating from recommended levels because of the unbalanced development of macronutrient intake levels; more improvement exists in fat and energy intake levels and less agreement in fruit-vegetable and animal protein intake levels. Scenario application proves that the relationship between ENI and undernutrition could readily be applied in future scenarios generated by integrated assessment models to provide insights into the impacts of various climate change scenarios, socioeconomic development pathways and alternative global trade policies on global hunger and undernutrition status.
Global food security is increasingly threatened by climate change and regional human conflicts. A... more Global food security is increasingly threatened by climate change and regional human conflicts. Abnormal fluctuations in crop production in major exporting countries can cause volatility in food prices and household consumption in importing countries. Here we show that timely forecasting of crop harvest from satellite data over major exporting regions can trigger production response in the opposite hemisphere to offset the short-term fluctuations and stabilize global food supply. Satellite forecasting can reduce the fluctuation extents of country-level prices by 1.1 to 12.5 percentage points for anticipated wheat shortage or surplus in Russia and Ukraine, and even reverse the price shock in importing countries for anticipated soybean shortage in Brazil. Our research demonstrates that by leveraging the seasonal lags in crop calendars between the Northern and Southern Hemispheres, operational crop monitoring from satellite data can provide a mechanism to improve global food security.
It has been shown that the proportion of intense tropical cyclones (TCs) has been increasing toge... more It has been shown that the proportion of intense tropical cyclones (TCs) has been increasing together with a poleward migration of TC track. However, their relative importance to TC surge at landfall remains unknown. Here we examine the sensitivity of TC surge in Shanghai to landfall location and intensity with a new dynamical modelling framework. We find a surge sensitivity of 0.8 m (°N)−1 to landfall location, and 0.1 m (m s−1)−1 to wind speed in Shanghai during landfall. The landfall location and intensity are comparably important to surge variation. However, based on a plausible range of reported trends of TC poleward migration and intensity, the potential surge hazard due to poleward migration is estimated to be about three times larger than that by intensity change. The long‐term surge risk in Shanghai is therefore substantially more sensitive to changes of TC track and landfall location than intensity. This may also be true elsewhere and in the future.
Toxic chemicals have severe impacts on ecosystem, climate change and human health, and the curren... more Toxic chemicals have severe impacts on ecosystem, climate change and human health, and the current toxic releases are inequitably distributed across regions. Investigating the toxic release embodied in final demand by states and income groups can reveal the responsibility transfer of different entities. In this paper, we extended the U.S. multi-regional input-output (MRIO) model with toxic chemical release data in 2017 to conduct the production-and consumption-based accounting of toxic release by each state, and the interregional transfer of embodied toxic release between states. In addition, this paper analyzed how the toxic releases and interstate transfer of embodied toxic release have been driven by income groups across states. The results showed that the toxic release from production was highly concentrated on the central states and the Great Lakes Region, while the consumption-based accounting of toxic release was more equally distributed across regions in the US. The non-metallic and metallic products manufacturing sectors were the most important sectors for most states from both production and consumption-based perspectives and were also the most essential sectors for interregional flows of embodied toxic release from Great Lake Region to Southeast, Mid-Atlantic and Northeast. Our results also showed that the largest portion (41.88%) of embodied toxic releases were triggered by households' final demand, and that the consumption of the richest 35% of households contributed to more than 50% of the total toxic chemical releases triggered by total final demand of all households.
Double-rice cropping (DRC) in southern China has made outstanding contributions to ensuring food ... more Double-rice cropping (DRC) in southern China has made outstanding contributions to ensuring food security, along with a large amount of greenhouse gas (GHG) emissions. The observed significant shift from double- to single-rice (DtS) cropping since 1990 in southern China has led to great concerns on food security, despite its contribution to GHG emissions reduction. How to ensure food security without compromising the goal of mitigating GHG emission requires innovative thinking and a comprehensive tradeoff analysis of all plausible options. This study adopts a multi-model coupling method to simulate the yield and GHG emissions trade-offs across grid-cells by incorporating the option of planting elite super rice in the DtS areas. The simulation results indicate that planting elite super rice with longer growth period in the DtS areas has the potential to compensate the annual yield loss caused by the DtS shift while significantly mitigating GHG emissions in comparison with the convent...
Global greenhouse gas (GHG) emissions can be traced to five economic sectors: energy, industry, b... more Global greenhouse gas (GHG) emissions can be traced to five economic sectors: energy, industry, buildings, transport and AFOLU (agriculture, forestry and other land uses). In this topical review, we synthesise the literature to explain recent trends in global and regional emissions in each of these sectors. To contextualise our review, we present estimates of GHG emissions trends by sector from 1990 to 2018, describing the major sources of emissions growth, stability and decline across ten global regions. Overall, the literature and data emphasise that progress towards reducing GHG emissions has been limited. The prominent global pattern is a continuation of underlying drivers with few signs of emerging limits to demand, nor of a deep shift towards the delivery of low and zero carbon services across sectors. We observe a moderate decarbonisation of energy systems in Europe and North America, driven by fuel switching and the increasing penetration of renewables. By contrast, in rapid...
Rapid economic growth and urbanization in China have led to a substantial change in consumption p... more Rapid economic growth and urbanization in China have led to a substantial change in consumption patterns and diet structure of Chinese consumers over the past few decades. A growing demand for feed, fuel and fiber also places intense pressure on land resources. With continuing growth of China's economy and migration from rural to urban, the increase in food consumption and change in diet structure will likely continue, which will not only impose pressure on domestic land resources but also exert impact on land resources in other countries through import. This article applies a global multiregion input-output (MRIO) model to trace agricultural land use along global supply chains and examines the impact of China's future food consumption on global land use in 2030 against different socioeconomic and technological scenarios. Our result shows that by 2030, China would need an additional 21% of cropland to support its increasing food demand driven by population growth, urbanization and income growth and the associated diet structure change. Almost a third of cropland associated with household consumption (34 Mha) will be "outsourced" to foreign countries, such as Argentina, Brazil, United States and Thailand, for the consumption of cereal grains, soybeans and paddy rice. China also consumes 2.4 Mha cropland from Africa for its consumption of cereal grains and oil seeds. The dependence of domestic consumption on significant amounts of foreign cropland shows that China would face serious challenges to meet its grain selfsufficiency policy in the future, and at the same time this dependence would contribute to environmental and food security problems elsewhere.
Protected areas (PAs) have been regarded as a critical strategy to protect natural forest (NF) an... more Protected areas (PAs) have been regarded as a critical strategy to protect natural forest (NF) and biodiversity. Estate-crop expansion is an important driver of deforestation in Indonesia. Yet, little is known regarding the temporal dynamics of PA effectiveness in preventing estate-crop expansion into NF. We employ Cox proportional hazard models and their extensions to characterize the dynamics of estate-crop expansion into NF in Indonesia during 1996-2015. The results show that PA effectiveness in Sumatra decreased over time and became insignificant in 2012-2015. A multistate modeling analysis shows that hopping in land-cover and land-use change (LCLUC) trajectories with shrub and/or bare ground as intermediates has decreased PA effectiveness and facilitated the expansion. Preventing LCLUC trajectory hopping becomes crucial to biodiversity conservation because it tends to occur at lowland forest, diminishing natural habitat area and increasing NF isolation. K E Y W O R D S deforestation, estate-crop expansion, Indonesia, multistate modeling, protected area This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Biofuels play a critical role in the Paris Agreement to help achieve climate change mitigation ta... more Biofuels play a critical role in the Paris Agreement to help achieve climate change mitigation targets. However, a significant increase in production of biofuels might potentially be realized at the expense of overusing natural resources, particularly land and water. Understanding the tradeoffs between the impacts on land and water arises as a critical issue in the development of biofuels. This energy-water-land nexus might be particularly important for Brazil, which currently is the world's second largest producer and the largest exporter of biofuels. Furthermore, Brazil itself has set up its own Intended Nationally Determined Contribution agenda with a significant growth of biofuel production (18%) by 2030. Most studies on environmental impacts of biofuel production have either focused on land use or water use, but very few studies assessed both. Using an environmentally extended multiregional input-output (MRIO) approach, this study analyzes the current water-land nexus of bioenergy production in Brazil by quantifying the distribution of tradeoffs and synergies between land and water use for bioethanol production and its environmental consequences across Brazilian states. Our results show a clear tradeoff of water and land impacts and significant differences between irrigated and rainfed ethanol production. When including water and land scarcity in the analysis, the results are significantly different, uncovering very different tradeoffs and synergies between bioethanol producer and consumer states that could inform the expansion of bioenergy in Brazil. Compared to other crops, sugarcane has a higher comparative advantage relative to land than to water.
Soybean is an important source of protein for humans and livestock. The steadily increasing deman... more Soybean is an important source of protein for humans and livestock. The steadily increasing demand fo soybean and global climate change both have brought great concern on risks and uncertainty in soybean supply. While fieldwork reports suggest that soybean farmers are aware of the risks posed by climate change and are adopting adaptive and mitigating measures, few studies have simulated and quantitatively assessed the effects of these adaptive techniques. In this study, we established a model coupling procedure between Decision Support System for Agrotechnology Transfer (DSSAT) and the China Agro-ecological Zone model (AEZ-China) to simulate soybean production based on observation records of soybean growth at 13 agro-meteorological observation stations in northeasten China and the Huang-Huai-Hai Plain over 1981-2011. The coupling procedure takes the advantage of DSSAT in its ability to calibrate the eco-physiological parameters based on simulating the dynamic bio-physiological processes of crop growth in daily step and the advantage of AEZ in rapidly evaluating the effects of shifts in planting day and changes in the length of growth cycle. Results indicate that climate change would result in beneficial effects in Northeastern China and cause losses in the Huang-Huai-Hai Plain in 2050s, the simulations using adaptive planting dates and cultivars with adaptive length of growth-cycle show that the losses can be reduced obviously.
It has been shown that the proportion of intense tropical cyclones (TCs) has been increasing toge... more It has been shown that the proportion of intense tropical cyclones (TCs) has been increasing together with a poleward migration of TC track. However, their relative importance to TC surge at landfall remains unknown. Here we examine the sensitivity of TC surge in Shanghai to landfall location and intensity with a new dynamical modelling framework. We find a surge sensitivity of 0.8 m (N) À1 to landfall location, and 0.1 m (m s À1) À1 to wind speed in Shanghai during landfall. The landfall location and intensity are comparably important to surge variation. However, based on a plausible range of reported trends of TC poleward migration and intensity, the potential surge hazard due to poleward migration is estimated to be about three times larger than that by intensity change. The long-term surge risk in Shanghai is therefore substantially more sensitive to changes of TC track and landfall location than intensity. This may also be true elsewhere and in the future. K E Y W O R D S climate change, landfall, storm surge, tropical cyclone 1 | INTRODUCTION Tropical cyclone (TC) related hazards pose the greatest threat to coastal regions (Pielke et al., 2008; Rappaport, 2014), especially in East Asia where the population and economy are growing rapidly and are vulnerable to natural hazards (Small and Nicholls, 2003). China has the highest rate of TC landfalls in the world (Fudeyasu and Wang, 2011), and China's coastal provinces, exposed directly to landfall TC hazards, account for more than half of China's GDP in 2019. Shanghai, the financial centre of China, is ranked as a top-10 city in the
Abstract Paddy rice cultivation is an important source of agricultural greenhouse gas emissions i... more Abstract Paddy rice cultivation is an important source of agricultural greenhouse gas emissions in China. The traditional flooded paddy rice fields not only use large amounts of irrigation water, but also produce significant methane (CH4) emissions. To balance food security with environmental impacts of rice production, many water-saving irrigations technologies have been tested in the field to increase the drainage period during the rice growth cycle. However, whether these management solutions can be implemented at the regional scale needs to be further explored. Because it is too time-consuming and resource-intensive for field experiments to be carried out across large areas, we opt to assess the regional impacts of alternative irrigation schemes via computer modeling, by coupling the well-known DSSAT and DNDC models, which have been extensively validated in China. Irrigation methods tested include the traditional Continuous Flooding (CF), Midseason Drainage (MD) and Alternate Wetting and Drying (AWD). Simulation results show that compared with CF, water-saving irrigation methods can significantly reduce the CH4 emission from paddy rice field, with slight or no loss in expected rice yields. AWD had the greatest effect in reducing irrigation water amounts and CH4 emission. Compared with CF, CH4 emission under the AWD were 60% - 71% lower in Northeast China sites and 34% - 65% lower in South China sites. At the same time, compared to CF, irrigation water use in AWD was reduced by 23% - 34% in northeast China sites and by 18% - 50% in south China sites. Our results suggest that policies that support expansion of AWD in paddy rice cultivation across China can lead to a “win-win” for the food-water-GHG emissions tradeoffs, and offer a viable solution for policy makers and stakeholders in China.
This paper presents an up-to-date survey of the comparison issue between state-owned enterprises ... more This paper presents an up-to-date survey of the comparison issue between state-owned enterprises (SOEs) and township-village enterprises (TVEs) in China. Although TVEs are at a disadvantage in areas such as technology, labor skills, education levels of staff. access to bank loans and government supports, they have important advantages in ownership and governance structures, personnel systems and labor relations, and conditions of institutional arrangement. These advantages apparently have outweighed the disadvantages, allowing the TVEs to outperform SO Es and successfully expand their market shares that previously belonged to the SOEs. However, our analysis also reveals that SOEs may not have performed so badly if their broad social contributions other than reported profits are also taken into account. Jn conclusion, we argue that both SOEs and TVEs need to reform their ownership and governance structures. Jn particular, if TVEs are to develop further during the next century, they cannot avoid the grassroots democratization.
Food and nutrition security has been a persistent major challenge to human societies and this cha... more Food and nutrition security has been a persistent major challenge to human societies and this challenge continues into the 21st century, especially taking into consideration the targets set by the UN Sustainable Development Goals, which call for eradicating hunger (goal 2), ending poverty (goal 1), sustainably managing and using natural resources and ecosystems (goal 15), and combating climate change (goal 13). The way food is consumed and produced affects the human well-being as well as the environment. Avoiding food losses and adopting a balanced healthy diet is also an important step towards sustainability. Promoting dietary standards and monitoring their adoption is a potentially important policy tool for mitigating environmental impacts of food production as well as monitoring food security and nutrition. There is relatively little research to measure nutritional adequacy of food intake according to dietary standards, and to explore the relationship with health outcomes. In this study we choose the well-established WHO global-level dietary recommendations as a reference to quantify nutritional adequacy by developing an energy and macronutrient intake index (ENI), and to assess its relation to indicators of hunger and undernutrition. We find strong negative association between nutritional adequacy of dietary intake and prevalence of undernutrition at national level, and we illustrate that ENI could be an effective tool to inform national food security strategies. Under different future socioeconomic development scenarios, almost all sub-Saharan African countries achieve an adequate per capita energy intake level but their nutritional status varies with many countries deviating from recommended levels because of the unbalanced development of macronutrient intake levels; more improvement exists in fat and energy intake levels and less agreement in fruit-vegetable and animal protein intake levels. Scenario application proves that the relationship between ENI and undernutrition could readily be applied in future scenarios generated by integrated assessment models to provide insights into the impacts of various climate change scenarios, socioeconomic development pathways and alternative global trade policies on global hunger and undernutrition status.
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