The discipline of geography encompasses both natural and social sciences and has the natural advantage of enabling the study of sustainability from a transdisciplinary perspective. There are great opportunities for geographers to participate in sustainability research. However, while geographers have set sustainability goals, they have rarely clarified the details for reaching those goals. Current knowledge on the relationship between humans and the environment and the methodologies for studying this relationship are inadequate to solve the transdisciplinary questions in sustainability science. Five research areas: geographical processes; ecosystem services and human wellbeing; human-environmental systems; sustainable development; and geo-data and modelling for sustainability are proposed as those needed to help geography achieve sustainability. The key objective of promoting geography for sustainability is to reveal the mechanisms of human-environmental system dynamics. This depends on understanding the processes in the natural and social systems and their mutual feedback as well as clarifying the relationships between the structures, functional characteristics and interactions in the human-environmental systems at multiple scales. The advancement of geography and its methodologies and technologies will provide a more profound understanding of the future. Geographers have the responsibility of promoting the discipline as the key pathway for carrying natural and social sciences towards sustainability.
Water footprint (WF) measures human appropriation of water resources for consumptive use of surface and ground water (blue WF) and soil water (green WF) and for assimilating polluted water (grey WF). Questions have been often asked about the exact meaning behind the numbers from WF accounting. However, to date environmental sustainability of WF has never been assessed at the sub-national level over time. This study evaluated the environmental sustainability of blue, green and grey WF for China's 31 mainland provinces in 2002, 2007 and 2012, and identified the unsustainable hotspots. Overall, the total WF increased by 30% between 2002 and 2012. The growth can be attributed to the increase of grey WF because the green and blue WF showed only a slight rise. Among all provinces investigated in 2012, eleven showed unsustainable blue WF (sustainability index SI<0), which were mainly located in the North China Plain. There were 12 provinces that displayed unsustainable green WF, and they were distributed in China's southern and southeastern areas. The grey WF was not sustainable in approximately two third of provinces (19), which were mainly located in China's middle and northern regions and Guangdong province. More than half of China's provinces showed trends of improved SI of green and blue WF from 2002 to 2012. However, the SI of grey WF decreased in almost two third of provinces. Poor levels of WF sustainability were due to water scarcity and pollution, which intensify the degradation of local rivers and ecosystems and make restoration more difficult. The results shed light on the policy making needed to improve sustainable water management, and ecological restoration of hotspot regions.
After the United Nations Agenda 2030 was officially launched in September 2015, governments around the world have taken actions to implement the ambitious plan. This paper summarizes the actions and policies taken in China for promoting the implementation of the UN’ 2030 Agenda for Sustainable Development, with emphasis on promoting the development of demonstration zones for delivery of the Sustainable Development Goals (SDGs). The Chinese government has taken two types of measures. One is to formulate a series of national plans and strategies and the other is to construct pilot and demonstration zones. Two approaches were presented to optimize the selection criteria for demonstration zones: a problem-based approach; and a major function-based approach. Both provided priority regions and major themes for selection and construction of demonstration zones. Suggestions for promoting the development of demonstration zones include: (1) building a monitoring system for the implementation of SDGs in each demonstration zone and establishing an open online platform to track the progress; (2) forming an effective stakeholder participation mechanism. The experiences in constructing innovation-driven demonstration zones are insightful for other countries to take practical actions in the delivery of SDGs.
To achieve the Sustainable Development Goals (SDGs), high-quality data are needed to inform the formulation of policies and investment decisions, to monitor progress towards the SDGs and to evaluate the impacts of policies. However, the data landscape is changing. With emerging big data and cloud-based services, there are new opportunities for data collection, influencing both official data collection processes and the operation of the programmes they monitor. This paper uses cases and examples to explore the potential of crowdsourcing and public earth observation (EO) data products for monitoring and tracking the SDGs. This paper suggests that cloud-based services that integrate crowdsourcing and public EO data products provide cost-effective solutions for monitoring and tracking the SDGs, particularly for low-income countries. The paper also discusses the challenges of using cloud services and big data for SDG monitoring. Validation and quality control of public EO data is very important; otherwise, the user will be unable to assess the quality of the data or use it with confidence.
The Sustainable Development Goals (SDGs) of the United Nations 2030 Agenda are a key focus for implementing the Sustainable Development (SD) concept. But generally speaking, SD goals and targets are continuously evolving, country specific, complex to implement, and are often given relatively short time horizons, such as the 15-year horizon for the SDGs. Many SD issues need a much longer time horizon as the policy interventions to deal with these issues can take decades before their effects become apparent, which is especially true for China. The T21 China 2050 is developed to study the long-term SD challenges and opportunities of the country. In its business-as-usual simulation to 2050, T21 China 2050 reveals some of the sustainability challenges facing China, including 1) aging population and labor force decline, 2) huge food imports, 3) land degradation and loss of arable land, 4) water shortages, 5) huge fossil fuel imports, and 6) carbon dioxide emissions. These SD issues are a subset of the SDGs specifically relevant to China over a time horizon well beyond 2030. The model is then used to test possible policy interventions in these six areas under two separate scenarios: Balanced and Narrowly Focused. The major results from these two scenarios are compared with those of the business-as-usual scenario. The simulations show that by adopting certain policy measures, China's path towards SD can be further improved. It also shows that a variety of policy measures can be selected and tested with the T21 China 2050 model for exploring the future SD prospects of the country. Specific policies recommended include: extension of retirement age, adjustment of the current family planning policy, protection of agriculture land, promotion of agricultural R&D to raise yield, improvement of public transportation to slow private vehicle ownership, increased investment in renewable energy, and water conservation.
Fire is a major type of disturbance that has important influences on ecosystem dynamics and carbon cycles. Yet our understanding of ecosystem fires and their carbon cycle consequences is still limited, largely due to the difficulty of large-scale fire monitoring and the complex interactions between fire, vegetation, climate, and anthropogenic factors. Here, using data from satellite-derived fire observations and ecosystem model simulations, we performed a comprehensive investigation of the spatial and temporal dynamics of China's ecosystem fire disturbances and their carbon emissions over the past two decades (1997-2016). Satellite-derived results showed that on average about 3.47 - 4.53 × 104 km2 of the land was burned annually during the past two decades, among which annual burned forest area was about 0.81 - 1.25 × 104 km2, accounting for 0.33-0.51% of the forest area in China. Biomass burning emitted about 23.02 TgC per year. Compared to satellite products, simulations from the Energy Exascale Earth System Land Model (ELM) strongly overestimated China's burned area and fire-induced carbon emissions. Annual burned area and fire-induced carbon emissions were high for boreal forest in Northeast China's Daxing'anling region and subtropical dry forest in South Yunnan, as revealed by both the satellite product and the model simulations. Our results suggest that climate and anthropogenic factors play critical roles in controlling the spatial and seasonal distribution of China's ecosystem fire disturbances. Our findings highlight the importance of multiple complementary approaches in assessing ecosystem fire disturbance and its carbon consequences. Further studies are required to improve the methods of observing and modelling China's ecosystem fire disturbances, which will provide valuable information for fire management and ecosystem sustainability in an era when both human activities and the natural environment are rapidly changing.
Soil organic carbon (SOC) in croplands is a key property of soil quality for ensuring food security and agricultural sustainability, and also plays a central role in the global carbon (C) budget. When managed sustainably, soils may play a critical role in mitigating climate change by sequestering C and decreasing greenhouse gas emissions into the atmosphere. However, the magnitude and spatio-temporal patterns of global cropland SOC are far from well constrained due to high land surface heterogeneity, complicated mechanisms, and multiple influencing factors. Here, we use a process-based agroecosystem model (DLEM-Ag) in combination with diverse spatially-explicit gridded environmental data to quantify the long-term trend of SOC storage in global cropland area during 1901-2010 and identify the relative impacts of climate change, elevated CO2, nitrogen deposition, land cover change, and land management practices such as nitrogen fertilizer use and irrigation. Model results show that the total SOC and SOC density in the 2000s increased by 125% and 48.8%, respectively, compared to the early 20th century. This SOC increase was primarily attributed to cropland expansion and nitrogen fertilizer use. Factorial analysis suggests that climate change reduced approximately 3.2% (or 2,166 Tg C) of the total SOC over the past 110 years. Our results indicate that croplands have a large potential to sequester C through implementing better land use management practices, which may partially offset SOC loss caused by climate change.
Agricultural landscapes cultivated in hilly and mountainous areas, often with terracing practice, could represent for some regions historical heritages and cultural ecosystem services. For this reason, they deserve to be protected. The complex morphology that characterises them, however, makes these areas intrinsically susceptible to hydrogeological instability, such as soil loss due to surface erosion or more severe mass movements. We can identify three major critical factors for such landscapes. The first is related to the socio-economic evolution of contemporary civilization, that increased the land abandonment of several rural regions, leading therefore to a lack of maintenance. A second element is the unsustainable agricultural practices, such as excessive heavy-mechanization that cause soil compaction thus accelerating degradation. Finally, the climate change forcing, with the increasing of the extreme rainfall. In this complex framework, it is necessary to find innovative solutions for the mitigation of hydrogeological risk and to respond in a well-prepared way to the possible future critical scenarios. Therefore, the use of sustainable agricultural practices, which allow the production of quality agricultural products in perfect harmony with the surrounding environment, becomes crucial. Suitable solutions must respond to the criterion of multidisciplinary, where the various stakeholders collaborate by offering their specific knowledge in a shared intention of problem-solving. The discipline of geography may become a valuable asset in this framework. In particular, thanks to the recent technological advances in the topographic survey (e.g. innovative remote sensing techniques such as drones and airborne laser scanning), it is possible to exploit digital terrain analysis to synthesize key information for decision-makers, in order to plan sustainable interventions. Moreover, thanks to the high-resolution and accuracy offered by digital topography and the advanced morphometric algorithms, it is possible to tackle the problem of hydrogeological risk from a unique and privileged perspective: that of prevention.
The outbreak of the 2019 novel coronavirus disease (COVID-19) has caused more than 100,000 people infected and thousands of deaths. Currently, the number of infections and deaths is still increasing rapidly. COVID-19 seriously threatens human health, production, life, social functioning and international relations. In the fight against COVID-19, Geographic Information Systems (GIS) and big data technologies have played an important role in many aspects, including the rapid aggregation of multi-source big data, rapid visualization of epidemic information, spatial tracking of confirmed cases, prediction of regional transmission, spatial segmentation of the epidemic risk and prevention level, balancing and management of the supply and demand of material resources, and social-emotional guidance and panic elimination, which provided solid spatial information support for decision-making, measures formulation, and effectiveness assessment of COVID-19 prevention and control. GIS has developed and matured relatively quickly and has a complete technological route for data preparation, platform construction, model construction, and map production. However, for the struggle against the widespread epidemic, the main challenge is finding strategies to adjust traditional technical methods and improve speed and accuracy of information provision for social management. At the data level, in the era of big data, data no longer come mainly from the government but are gathered from more diverse enterprises. As a result, the use of GIS faces difficulties in data acquisition and the integration of heterogeneous data, which requires governments, businesses, and academic institutions to jointly promote the formulation of relevant policies. At the technical level, spatial analysis methods for big data are in the ascendancy. Currently and for a long time in the future, the development of GIS should be strengthened to form a data-driven system for rapid knowledge acquisition, which signifies that GIS should be used to reinforce the social operation parameterization of models and methods, especially when providing support for social management.
Increased pressure on the earth's resources has led to what is increasingly referred to as the climate crisis. While a whole range of environmental parameters have been transformed through such pressures, the effect of human activities on the climate is symbolic of the nature of the human footprint upon our planet and makes the lack of any coherent political leadership in most countries even more alarming. The discipline of Geography has a distinct advantage in developing a more holistic understanding of global environmental challenges in that it reaches across all the sciences (including social sciences and humanities). Geographical education therefore represents an important vehicle for citizens of all ages to help them understand the complexity of the sustainability goal and what can (and should) be done to achieve a more sustainable future. In this essay, I reflect on three approaches that are available to individuals and communities towards taking the steps to sustainability. The philosophy embodied by the International Year of Global Understanding (IYGU) is suggested as a particularly valuable tool for geography educators. The activities of the International Geographical Union (IGU) offer important opportunities for geographers to learn from each other and promote best practice in geographical education. As ‘the science for sustainability’, Geography has an increasingly important role to play in developing the knowledge and the skills to equip future generations with the tools to adapt to and mitigate potentially catastrophic global environmental change.