Human-earth system dynamics in China's land use pattern transformation amidst climate fluctuations and human activities.

Amid rapid environmental changes, the interplay between climate change and human activity is reshaping land use, emphasizing the significance of human-earth system dynamics. This study, rooted in human-earth system theory, explores the complex relationships between land use patterns, climate change, and human activities across China from 1996 to 2022. Using a comprehensive analytical framework that combines Geographical Detector (GeoDetector), Random Forest (RF) model, Data Envelopment Analysis (DEA), Spearman's rank correlation, and k-means clustering, we analyzed data from national land surveys, climate records, and nighttime light observations. Our findings indicate a significant, though regionally varied, transformation in land use: arable land decreased by 1.67 %, driven by intense urbanization and policy shifts, particularly in rapidly urbanizing Jiangsu province where arable land diminished by 19.19 %. In contrast, construction land in the northern regions increased by 225.91 million hectares. Climatic influences are apparent, with rising temperatures positively correlating with arable land expansion in the Northeast and Northwest, and urban land in Jiangsu province increasing by 35.51 %. Variations in precipitation patterns were linked to changes in forested areas. This study highlights the dynamic and intricate interactions within the human-earth system, stressing the urgent need for sustainable land management and climate adaptation strategies that improve land use efficiency and resilience. Our research offers a solid foundation for informed policy-making in land management and climate adaptation, advocating a human-earth system science approach to address future environmental and societal challenges.

Exploring the evolution of ecosystem health and sustainable zoning: A perspective based on the contributions of climate change and human activities.

Maintaining ecosystem health (EH) in watersheds is crucial for building a national pattern of ecological security. However, a comprehensive diagnosis of watershed EH and an exploration of its driving mechanisms are still lacking. This study proposed an EH assessment model from a vitality-organization-resilience-service-environment (VORSE) perspective. Taking the Yellow River Basin of Shaanxi Province (YRBS), China, as a research object, the spatiotemporal evolution trend of EH from 2000 to 2020 was quantified. At the same time, we also quantified the respective contributions of climate change (CC) and human activities (HA) to the EH dynamics based on residual analysis. The results showed that EH in the YRBS increased by 11.80 % from 2000 to 2020, and the spatial distribution of the EH was higher in the southern region than in the northern part. At the pixel scale, areas with improving trends accounted for 90.57 % of the YRBS, while 9.43 % deteriorated, with the improving areas mainly in northern Shaanxi and the deteriorating areas in the Guanzhong region. The correlation between the EH and precipitation was primarily positive, while the correlation between the EH and temperature was mainly negative. The residual analysis showed that the contribution rate of CC to EH changes was 78.54 %, while that of HA was 21.46 %, indicating that CC was the dominant driver of EH changes in the YRBS. Specifically, 82.64 % of the improvement in EH was attributed to CC and 17.36 % to HA. Conversely, 65.30 % of the deterioration in EH was attributed to CC and 34.70 % to HA. Furthermore, CC, HA, and CC&HA dominated EH changes in 26.85 %, 3.77 %, and 69.38 % of the YRBS area, respectively. In addition, the Hurst exponent analysis identified six types of future EH development scenarios, each requiring different restoration strategies. This study provides valuable insights for future EH diagnosis, EH restoration efforts, and the formulation of sustainable development goals in other watersheds.

Regularity of rural settlement changes driven by rapid urbanization in North China over the three decades.

The systematic decline of rural areas in the process of rapid urbanization has become a global trend, creating greater challenges for sustainable rural development. As the spatial projection of socio-economic development and living environment in rural areas, the continuous tracking of rural settlements (RUS) is crucial to quantify the imbalance of rural development. However, consistent information on RUS is highly needed but is quite deficient in current research. In this study, a cost-effective mapping model was proposed to produce an annual RUS dataset in the rapid urbanization region of Beijing-Tianjin-Hebei (BTH) in North China during 1990-2020, and the temporal-spatial regularity of RUS changes was further analyzed. The location-based and the area-based comparison verified the effectiveness of our model, with a mean overall accuracy of 85% and a mean correlation value of 0.88, respectively. The total area of RUS in the BTH region increased by 2561 km2 from 1990 to 2020, while the average size of RUS remained stable after 2005. The annual change trends in RUS appeared with increasing and decreasing accounting for 76.33% and 23.67%, respectively. The centroids of RUS in Tianjin and Hebei have moved closer to Beijing, while those in Beijing have moved away from the former. Notably, we have identified 56.3% counties in the BTH region belong to the "Convex-I" change type in RUS. In general, our work can help to consistently quantify the spatiotemporal patterns of RUS in a cost-effective way, providing more explicit spatial information and continuous temporal information for rural residential land management.

Sustainable poverty reduction models for the coordinated development of the social economy and environment in China.

Sustainable development in impoverished areas is still a global challenge owing to trade-offs between development and conservation. There are large poverty-stricken areas (PSAs) in China, which overlap highly with ecologically sensitive areas. China has made great efforts to alleviate poverty over the years. The coordinated relationship between the social economy and the environment in PSAs, however, remains under-recognized. This study developed a county-level index system encompassing the socioeconomic and environmental sectors of China's PSAs. The integrated indexes of the two sectors were developed to reveal the spatial-temporal socioeconomic and environmental patterns and coupling coordination degree (CCD) levels were calculated to assess the coordinated relationships between them. The CCD indicated the increasingly coordinated development of socioeconomic and environmental conditions in China's PSAs from 2000 to 2020. Meanwhile, although the socioeconomic index achieved considerable growth with a growth rate of 58.4%, the environmental index was mildly improved with a growth rate of 19.6%, instead of a reduction. PSAs still have a large gap in socioeconomic development compared to non-poor areas; however, PSAs perform better in environmental index. Overall, the increased coordinated development between the social economy and the environment from 2000 to 2020 can be attributed to China's long-term, large-scale, and targeted interventions in poverty reduction and environmental conservation. Further, benefiting from the geodiversity of China, we identified four poverty reduction models which include advantageously, sustained, periodic, and limited effective models, on the basis of CCD change patterns. The four models can provide valuable experience for the rest of the world in tackling similar trade-offs of poverty reduction and environmental challenges.

Spatial-temporal evolution of agricultural ecological risks in China in recent 40 years.

Excessive use of agricultural chemicals and unreasonable utilization of agricultural wastes have led to severe agricultural non-point source pollution (ANPSP) problems in China. Based on the agricultural pollution loads and pollution control strength, the ecological risk index (ERI) was constructed and was used to explore the spatial-temporal pattern of agricultural ecological risks in China during 1978-2017. The findings indicated that Chinese agricultural ERI was gradually increased from 0.031 to 0.348 in 1978-2017, which has the same phased change characteristics as the succession of agricultural policies. At present, the ecological risk grade of ANPSP was present in the stair-step distribution characteristics of "high in the east and south and low in the west and north" as a whole. Southern China, as the main producing area of aquatic products, had the higher ecological risks. Northeastern China, the Huang-Huai-Hai Area, and the middle and lower reaches of the Yangtze River, as the grain-producing bases, had moderate ecological risks, but Southwestern China and Northwestern China with the poor agricultural production conditions had the lower ecological risks. It evidently showed that the ecological risk problems faced by the high-quality development of Chinese agricultural industrialization are increasingly severe.

The Global South political economy of health financing and spending landscape - history and presence.

The Global South nations and their statehoods have presented a driving force of economic and social development through most of the written history of humankind. China and India have been traditionally accounted as the economic powerhouses of the past. In recent decades, we have witnessed reestablishment of the traditional world economic structure as per Agnus Maddison Project data. These profound changes have led to accelerated real GDP growth across many LMICs and emerging countries of the Global South. This evolution had a profound impact on an evolving health financing landscape. This review revealed hidden patterns and explained the driving forces behind the political economy of health spending in these vast world regions. The medical device and pharmaceutical industry play a crucial role in addressing the unmet medical needs of rising middle class citizens across Asia, Latin America, and Africa. Domestic manufacturing has only been partially meeting this ever rising demand for medical services and medicines. The rest was complemented by the participation of multinational pharmaceutical industry, whose focus on investment into East Asia and ASEAN nations remains part of long-term market access strategies. Understanding of the past remains essential for the development of successful health strategies for the present. Political economy has been driving the evolution of health financing landscape since the establishment of early modern health systems in these countries. Fiscal gaps these governments face in diverse ways might be partially overcome with the spreading of cost-effectiveness based decision-making and health technology assessment capacities. The considerable remaining challenges ranging from insufficient reimbursement rates, large out-of-pocket spending, and lengthy lag in the introduction of cutting-edge technologies such as monoclonal antibodies, biosimilars, or targeted oncology agents, might be partially resolved only in the long run.

Impacts of climatic warming on cropping system borders of China and potential adaptation strategies for regional agriculture development.

Climate warming and its corresponding impacts on agriculture system increasingly attach great attentions. Earlier studies more concerned the impacts of the cultivated area expansion under climate change. Yet limited knowledge is about the impacts of climate warming on the cropping index change with the shifts of cropping system border. In this study, we used climatic data (1961-2015) to firstly investigate impacts of warming temperature on potential cropping system border expansion of China, and further used agricultural statistical data and satellite-based land use data to analyze the response of current land system to potential cropping system border expansion. Results of this study indicated that obviously advanced SDT10 and prolonged EDT10 contributed to the 88.4% regions of increased AAT10 at the past half century. Moreover, the northward expansion of the suitable cultivated areas in different cropping systems provided advantages for potential multiple cropping index (PMCI) improvement. Unfortunately, this study found that a significantly declined multiple cropping index (MCI) was observed in the peri-urban regions and the provinces with large out-migration of agriculture labor. The evidently increased MCI was only greatly observed in Xinjiang province. Besides, the potential increment of multiple cropping index (PIMCI) for different cropping system border expansion regions presented a rising trend and reached 53.6% in 2015 due to warming climate. Particularly, the significantly increased PIMCI was observed in the Loess Plateau, the Inner Mongolia, the Middle-lower Yangtze Plain, Northeast China Plain, Southern China and Beijing-Tianjin-Hebei Metropolitan Region. However, the response of current land system to the changes of PMCI and PIMCI was not timely. Based on the findings of our study, some potential agriculture development strategies were suggested by comprehensively considering regional natural conditions, agricultural production conditions and socioeconomic conditions. We hope these findings of this study could provide some valuable information for agricultural development policy decision-making.

Characteristics of temperature evolution from 1960 to 2015 in the Three Rivers' Headstream Region, Qinghai, China.

The cumulative anomaly analysis, the ensemble empirical mode decomposition (EEMD), the Bernaola Galvan heuristic segmentation algorithm (BGSA), the Le Page test, the moving t test at different sub-series scales, and the quasi-periodic oscillations (QPOs) were used to demonstrate the statistical characteristics of the temperature changes in the study area from 1960 to 2015. The results were as follows: the temperatures varied obviously among subregions and seasons and they generally increased; the climate tendency rates of autumn mean temperatures were higher than those of summer and spring; additionally, the temperatures in the three subregions of the Three Rivers' Headstream Region (THRHR) were relatively low in the 1960s, especially in the early 1960s, followed by those in the 1970s, and the annual mean temperature has been increasing since the mid-late 1980s, especially in the middle 1990s. The results of EEMD showed that the QPOs of the annual mean temperature series in the study area were mainly quasi-3 years, quasi-5-8 years, quasi-12-15 years, and quasi-35-38 years. The results of the annual mean temperature series mutational sites showed that a significant warming mutation began in approximately 1997; and the mutational sites of seasonal mean temperature series in the three subregions of the THRHR all began in the middle and late 1990s. The prediction result of the temperature series trend based on multiple methods showed that the warming persistence of annual and seasonal mean temperature series would be stronger, and their seasonal and regional differences were obvious.

Exploring the relationship between air pollution and meteorological conditions in China under environmental governance.

Extensive studies have been carried out on the impact of human activities on air pollution, but systematic investigation on the relationship between air pollutant and meteorological conditions is still insufficient, especially in the context of China's site scale and recent comprehensive environmental pollution control. Here, we used a spatial interpolation technology to establish a set of data sets of pollutants and meteorological elements that are spatially matched at 896 stations in China to reveal the air pollutant-meteorological interactions between 2014 and 2019. We found that air pollution and meteorological elements have obvious seasonal and regional characteristics. Over the last few years, the concentration of most air pollutants in China has dropped significantly except for O3. The increase in O3 concentration was closely related to the decrease of particulate matter and NO2 concentration. The concentration of most air pollutants was affected by meteorological conditions, but the level of impact depended on the type of pollutants and varied across regions. The concentration of air pollutants at most stations was significantly negatively correlated with wind speed, precipitation and relative humidity, but positively correlated with atmospheric pressure. As the latitude increases, the impact of temperature on the concentration of air pollutants becomes more obvious. To effectively control air pollution, it is further urgent to reveal the relationship between air pollution and meteorological conditions based on long-term daily or real-time data.

Assessment and analysis of agricultural non-point source pollution loads in China: 1978-2017.

China's successful agriculture development has resulted in public concerned environmental problems. However, continuous and detailed data about Chinese agricultural non-point source pollution (ANPSP) loads are lacking. To assess and analyze Chinese ANPSP loads from 1978 to 2017, an inventory analysis was performed, and a socioeconomic and spatiotemporal analysis in the scale of provinces was conducted. The results showed that the pollution loads of chemical oxygen demand (COD), total nitrogen (TN) and total phosphorus (TP) increased by 91.0%, 196.2% and 244.1%, respectively, and their variation underwent a free development stage, reform promotion stage, market regulation stage and policy incentive stage. The results of the pollution source analysis showed that over the past 40 years, the total percent contribution to COD by livestock and poultry breeding (LPB) and rural household waste (RHW) accounted for 83.1%-96.6%, the total percent contribution to TN by mineral fertilizers (MF) and LPB accounted for 72.3%-80.8%, and the total percent contribution to TP by LPB, RHW and MF accounted for 69.1%-88.6%. In addition, Shandong, Guangdong, Sichuan, and Henan were the top producers of ANPSP loads, and their COD, TN, and TP loads accounted for approximately 32%, 30%, and 35% of the national totals, respectively. The discharge intensity of COD, TN and TP decreased by 79.2%, 67.8%, and 62.6%, respectively. The discharge intensity exhibited a phasic feature that aligned with the national economic plan in the temporal scale and was closely related to the agricultural conditions in the spatial scale.

Health, income and poverty: evidence from China's rural household survey.

BACKGROUND: Understanding the health status of the poor households and the influence of unhealthy on their income can provide some vital insights into the effectiveness and appropriateness of poverty reduction solutions. METHODS: Based on a nationwide cross-sectional survey of 29,712 rural poor households, this study systematically investigated the causes of poverty and health status of Chinese rural poor households, and revealed the relationship between health, income and poverty. RESULTS: The health status of the rural poor in China is not optimistic, with 51.63% attributing their poverty to the illness of household members. NCDs are the biggest health threat to the rural poor in China. Over 60% of all the households have at least one patient and more than a quarter of the households with patients cannot afford expensive medical expenses. Although 98% of all the households participate in China's a rural health insurance system - the New Rural Cooperative Medical Scheme - 16% are still unable to bear their medical expenses after reimbursement from the scheme. Further, high altitude, ill-health and low-income are interlinked and mutually reinforcing. The per capita net income of poor households was inversely proportional to the altitude of their places of residence, family aging and unhealthy status, but was positively correlated with the number of workforces in their families. CONCLUSIONS: Poverty due to illness is one of the root causes of rural poverty in China. With the backward medical infrastructure in high altitude areas, people are more prone to fall into the vicious circle of poverty-unhealthy-low income-poverty. The establishment of effective long-term mechanism of disease prevention and intervention is an important prerequisite to enhance the endogenous development power of the poor and reduce poverty.

Biophysical effect of conversion from croplands to grasslands in water-limited temperate regions of China.

The biophysical effect of land use and land cover change (LUCC) on regional climatic regulation is currently of growing interest. However, in water-limited temperate regions, the net biophysical effect of conversion from croplands to grasslands on regional climatic regulation remains poorly understood to date. To answer this concern, a modified land surface model (mEASS) and two different land use scenarios in a typical study area of the Loess Plateau of China were used in this study. We first validated the performances of mEASS model by using observations from six flux tower sites with different land cover and three metrics of the coefficient of determination (R2), the root mean square error (RMSE) and the difference between the simulated and observed data (bias). Subsequently, the biophysical effect of conversion from croplands to grasslands was investigated. Results indicated that mEASS model could well capture the seasonal dynamics of net radiation and latent heat with high R2 and lower RMSE and bias at grassland, forest and cropland sites. In the context of semi-arid and semi-humid climatic conditions, conversion from croplands to grasslands caused the cooling effect (-0.3 W/m2) at the annual scale. Similar cooling effects were found in spring (-0.4 W/m2), autumn (-0.8 ±â€¯0.1 W/m2) and winter (-0.9 ±â€¯0.1 W/m2). The decreased latent heat (inducing warming effects) were completely offset by decreased net radiation (inducing cooling effects), which were responsible for the net cooling effects. However, a warming effect with 1.0 ±â€¯0.1 W/m2 was observed in summer. This is because that magnitude of decreased latent heat is greater than that of decreased net radiation in summer. These findings will enrich our understanding for the biophysical effect of conversion from croplands to grasslands in water-limited temperate regions.

Biochar amendment reduces paddy soil nitrogen leaching but increases net global warming potential in Ningxia irrigation, China.

The efficacy of biochar as an environmentally friendly agent for non-point source and climate change mitigation remains uncertain. Our goal was to test the impact of biochar amendment on paddy rice nitrogen (N) uptake, soil N leaching, and soil CH4 and N2O fluxes in northwest China. Biochar was applied at four rates (0, 4.5, 9 and13.5 t ha-1 yr-1). Biochar amendment significantly increased rice N uptake, soil total N concentration and the abundance of soil ammonia-oxidizing archaea (AOA), but it significantly reduced the soil NO3--N concentration and soil bulk density. Biochar significantly reduced NO3--N and NH4+-N leaching. The C2 and C3 treatments significantly increased the soil CH4 flux and reduced the soil N2O flux, leading to significantly increased net global warming potential (GWP). Soil NO3--N rather than NH4+-N was the key integrator of the soil CH4 and N2O fluxes. Our results indicate that a shift in abundance of the AOA community and increased rice N uptake are closely linked to the reduced soil NO3--N concentration under biochar amendment. Furthermore, soil NO3--N availability plays an important role in regulating soil inorganic N leaching and net GWP in rice paddies in northwest China.

Analyzing historical land use changes using a Historical Land Use Reconstruction Model: a case study in Zhenlai County, northeastern China.

Historical land use information is essential to understanding the impact of anthropogenic modification of land use/cover on the temporal dynamics of environmental and ecological issues. However, due to a lack of spatial explicitness, complete thematic details and the conversion types for historical land use changes, the majority of historical land use reconstructions do not sufficiently meet the requirements for an adequate model. Considering these shortcomings, we explored the possibility of constructing a spatially-explicit modeling framework (HLURM: Historical Land Use Reconstruction Model). Then a three-map comparison method was adopted to validate the projected reconstruction map. The reconstruction suggested that the HLURM model performed well in the spatial reconstruction of various land-use categories, and had a higher figure of merit (48.19%) than models used in other case studies. The largest land use/cover type in the study area was determined to be grassland, followed by arable land and wetland. Using the three-map comparison, we noticed that the major discrepancies in land use changes among the three maps were as a result of inconsistencies in the classification of land-use categories during the study period, rather than as a result of the simulation model.