Food Security and Land Use under Sustainable Development Goals: Insights from Food Supply to Demand Side and Limited Arable Land in China.

The conflict between economic growth and the arable land demand poses a significant challenge to maintaining food security and achieving the Sustainable Development Goals. Meanwhile, substantial regional disparities in food consumption contribute to variations in land demand, further exacerbating constraints on food security. However, few studies have delved into regional differences in land demand related to food consumption. To bridge these gaps, this study estimated the arable land demand and associated pressures, considering food consumption patterns and the land footprint across 31 provincial districts in China. The findings reveal that grains remain the primary crop consumed by Chinese residents. Notably, the food consumption pattern exhibits substantial disparities among provincial districts, particularly concerning livestock products. Given China's vast population and escalating consumption of livestock, the country demonstrates heightened land demands. While China does not face a national-level food security threat, regional disparities are evident, with eight provincial districts facing potential food security risks. This study explored the challenges and pathways in maintaining food security and the visions to achieve it, emphasizing the importance of sustaining a balanced food consumption pattern, reducing food waste, improving environmentally friendly agriculture practices, formulating effective and continuous laws and regulations, and exploring potential land resource development to alleviate the pressure on arable land and ensure food security.

Untangling interactions and prioritizations among Sustainable Development Goals in the Asian Water Tower region.

Understanding the interactions among Sustainable Development Goals (SDGs) is critical for prioritizing SDGs and accelerating the overall SDGs progress. However, SDG interactions and prioritizations at the regional scale have rarely been researched (e.g., Asia), and more importantly, their spatial differences and temporal variations remain elusive. Here, we focused on the Asian Water Tower region (16 countries), which represents major challenges for Asian and even global SDG progress, and we assessed the spatiotemporal variations in SDG interactions and prioritizations in the region from 2000 to 2020 based on correlation coefficients calculations and network analyses. We observed a striking spatial difference in the SDG interactions, which may be minimized by promoting balanced progress toward SDGs 1 (no poverty), 5 (gender equality), and 11 (sustainable cities and communities) across countries. The prioritization differences of the same SDG across countries ranged from 8 to 16 places. Temporally, the SDG trade-offs in the region have declined, implying a possible shift to synergies. However, such success has faced several obstacles, mainly climate change and a lack of partnerships. The prioritizations of SDGs 1 and 12 (responsible consumption and production) have shown the largest increase and decrease, respectively, over time. Overall, to accelerate the regional SDG progress, we highlight the importance of enhancing top prioritized SDGs 3 (good health and well-being), 4 (quality education), 6 (clean water and sanitation), 11, and 13 (climate actions). Related complex actions are also provided (e.g., across-scaled cooperation, interdisciplinary research, and sectoral transformation).

Linking ecosystem services and circuit theory to identify priority conservation and restoration areas from an ecological network perspective.

The Yellow River basin has been experiencing ecosystem fragmentation, conversion, and degradation. The ecological security pattern (ESP) can provide a systematic and holistic perspective for specific action planning to maintain ecosystem structural, functional stability, and its connectivity. Thus, this study focused on Sanmenxia, one of the most representative cities of the Yellow River basin, to construct an integrated ESP to provide evidence-based support for ecological conservation and restoration. We adopted four main steps, including measuring the importance of multiple ecosystem services, identifying ecological sources, constructing the ecological resistance surface, and linking the MCR model and circuit theory to identify the optimal path, optimal width, and key nodes of ecological corridors. Overall, we identified various ecological conservation and restoration priority areas in Sanmenxia, including 3593.08 km2 of ecosystem service hotspots, 28 corridors, 105 pinch points, and 73 barriers, and we highlighted multiple priority actions. This study provides an effective starting point for the future identification of ecological priorities at the regional or river basin scale.

The spatial analysis, risk assessment and source identification for mercury in a typical area with multiple pollution sources in southern China.

Mercury (Hg) has always been a research hot spot because of its high toxicity. This study conducted in farmland near rare earth mining area and traffic facilities, which considered multiple pollution sources innovatively. It not only analyzed Hg spatial characteristics using inverse distance weighting and self-organizing map (SOM), but also assessed its pollution risk by potential ecological risk index (Er) as well as geoaccumulation index (Igeo), and identified the pollution sources with positive matrix factorization. The results showed that there was no heavy Hg pollution in most farmland, while a few sampling sites with Hg pollution were close to highway, railway station and petrol station in Xinfeng or in the farmland of Anyuan, which were divided into the cluster with highest Hg concentration in SOM. The vehicle exhaust emission and pesticide as well as fertilizer additions significantly contributed to the local Hg pollution. Besides, there was moderate pollution and high ecological risk in Anyuan assessed by Igeo and Er, respectively. In contrast, Xinfeng had the moderate and considerable ecological risks in a larger scale. The enriched Hg might harmed not only the nearby ecological environment, but also the human health when it entered human body through food chain. The three factors that contributed to mercury concentration in this area according to positive matrix factorization were natural source, traffic source and agricultural source, respectively. This study about Hg pollution in the typical area would provide scientific evidence for the particular treatment of Hg pollution from various pollution sources like traffic source, agricultural source, etc.

Comprehensive efficiency evaluation of wastewater treatment plants in northeast Qinghai-Tibet Plateau using slack-based data envelopment analysis.

Comprehensive efficiency analysis of wastewater treatment plants (WWPTs) in the alpine region with harsh environment and poor techniques as well as managing experience could provide targeted and effective improvement evidences for local wastewater treatment industry and help to improve the water quality of downstream reaches. In this paper, slack-based data envelopment analysis (SBM-DEA) was adopted to assess the operating efficiencies of WWPTs in northeast Qinghai-Tibet Plateau (QTP). Results showed that the average efficiency score for all WWPTs was 0.608, and 32.5% of WWPTs were efficient. Some WWPTs had large improvement potentials in operating costs and pollutant removal rates. Lowering expenditures and promoting facility construction for WWPTs to overcome the climate difficulties and improve management level was necessary according to their improvement potentials. In addition, the relative importance of the quantitative influential factors to efficiencies scores calculated by random forest regression (RFR) indicated that design capacity and temperature were important quantitative factors affecting the performance of WWPTs. Furthermore, geographical location and design capacity also had significant influence on the comprehensive efficiency of WWPTs verified by Kruskal-Wallis test. Our results highlight the importance of facilities upgrading, scientific management for WWPTs. And the relative improvement suggestions on overcoming the high and cold environment should also be considered for the efficient operations of WWTPs as well as the protection the aquatic environment.

Concentrations, spatial distribution, sources and environmental health risks of potentially toxic elements in urban road dust across China.

Potentially toxic element (PTE) pollution is widespread in road dust across China, and the effects of PTEs in road dust on health cannot be ignored. In this study, the concentrations of six PTEs (Pb, Cd, Cr, Cu, Zn and Ni) in 4336 road dust samples from 58 cities in 31 provincial regions of China taken after 2000 were obtained from the literatures. Based on these data, the spatial distribution, pollution sources, and ecological and human health risks of PTEs in road dust were comprehensively assessed and the main pollution factors and areas of high risk were identified. The results revealed that PTE levels are generally higher in eastern cities than western cities in China. The key driving factors are socioeconomic factors, including those related to transportation, industry, and population, for which the contribution rates are 57.80%, 55.39% and 37.19%, respectively. PTEs in the road dust with high ecological risks are mainly distributed in the southeastern coastal areas and the Beijing-Tianjin-Hebei region. No obvious noncarcinogenic risk was found for PTEs in road dust, but Cd and Pb may have potential noncarcinogenic risk, mainly distributed in cities in western China. Therefore, regions and pollution sources contributing to Pb and Cd levels should be monitored. The control of PTE pollution in China is a priority for ecological and environmental protection.

A systematic method for assessing progress of achieving sustainable development goals: A case study of 15 countries.

17 sustainable development goals (SDGs) were committed by 193 countries in 2015. Assessing the spatio-temporal progress of achieving the SDGs can help to track the global sustainable development progress and identify critical development issues to eventually accelerate the achievement of SDGs. However, there is a lack of methods for the quantitative assessment of the progress of achieving SDGs at the regional level (above the national level), especially systematic methods that can simultaneously assess regions along the "Belt and Road". To fill this research gap, after classifying 17 SDGs into four dimensions (society, economy, environment, means of implementation and cooperation), we have developed the Composite SDG Index to represent the comprehensive performance of achieving SDGs. Specifically, the index is constructed by two sub-indices, including the SDG subindex used to assess the overall performance of achieving the four dimensional SDGs and the Coupling Coordinated SDG subindex used for the first time in the SDG assessment to measure the coupling coordination degree between the four SDG dimensions. To implement this methodological framework, we chose 15 countries along the "Belt and Road" as the case study, and used 108 indicators to assess the performance of achieving SDGs for these countries. Eventually, various national development models and related policy recommendations were proposed. The three indices included in the methodological framework developed in this study can effectively enhance the global stakeholders' mutual understanding of the progress of achieving SDGs to support regional coordinated planning and national-level strategic decision-making.