Identification and characteristic analysis of semi-natural habitats in China's economically developed areas: New insights to inform cultivated land system ecological conservation.

Identifying and characterizing semi-natural habitats (SNHs) are important to the ecological conservation of cultivated land systems and implementing China's ecological civilization strategy. This study revealed the concept and characteristics of SNHs in Chinese cultivated land systems regarding human activities, resource types, and spatial landscape patterns. The resource quantity, landscape quality, and spatial distribution of SNHs in Southern Jiangsu's cultivated land system were analyzed by constructing the identification model of "land use/land cover type-cultivated land use intensity-spatial landscape pattern". The results showed that the area of SNHs in Southern Jiangsu's cultivated land system was 25.35%, significantly influenced by cultivated land intensification and expansion. The higher the cultivated land use intensity, the lower the quantity of SNHs, and the proportion of SNHs in the intensive-use pattern was only 2.97%. 68.18% of the SNHs in Southern Jiangsu were water, and habitats for important species, such as woodland, grassland, wetlands, and bare land, were scarce. A small patch area, high landscape fragmentation, poor landscape richness and diversity, and low connectivity accompanied increased cultivated land use intensity. From the extensive to intensive utilization, the spatial spread of SNHs from low-value aggregation to high-value scatter areas, with hotspot areas of cultivated land use intensity and SNHs existing only in a small part of Nanjing and Changzhou. This study provides a scientific reference for the rehabilitation and restoration of SNHs in the context of the ecological transformation of land use. It promotes the sustainable intensification of cultivated land systems. It also provides new ideas for linking ecological and urban spaces to form a stable and systematic national ecological safety network.

Using modern portfolio theory to enhance ecosystem service delivery: A case study from China.

：Land management strategies often prioritize agricultural supply services at the expense of other ecosystem services. To achieve a high and steady supply of multiple ecosystem services, it is essential to optimize land management practices in areas suitable for agriculture. However, many studies on land management tend to focus on their benefits to ecosystem service delivery without adequately considering the potential risks to other services that might be involved. Here we use modern portfolio theory to quantitatively measure benefits and risks from land management strategies to enhance ecosystem services. We create seven land management scenarios that balance different kinds of ecosystem services in different ways in the agricultural production area of Maoming, Guangdong Province, China. The method yielded optimal portfolios of land management patterns that enhanced ecosystem services while reducing risk as much as possible. This includes a scenario delivering a 22% increase in agricultural production service, while simultaneously increasing the provision of nature-related ecosystem services by 2%. However, no optimization scenario was perfect, and there was always a trade-off between gaining certain ecosystem service benefits and creating a risk of losing others. Our portfolio theory approach reveals that it is essential to consider both the benefits and risks of land management strategies.

The role of harmonized Landsat Sentinel-2 (HLS) products to reveal multiple trajectories and determinants of cropland abandonment in subtropical mountainous areas.

Cropland abandonment is a widespread land-change process globally, which can stem from the accelerated outmigration of the population from rural to urban areas, socio-economic and political changes, catastrophes, and other trigger events. Clouds limit the utility of optical satellite data to monitor cropland abandonment in highly fragmented mountain agricultural landscapes of tropical and subtropical regions, including the south of China. Taking Nanjing County of China as an example, we developed a novel approach by utilizing multisource satellite (Landsat and Sentinel-2) imagery to map multiple trajectories of cropland abandonment (transitioning from cropland to grassland, shrubs and forest) in subtropical mountainous landscapes. Then, we employed a redundancy analysis (RDA) to identify the spatial association of cropland abandonment considering agricultural productivity, physiography, locational characteristics and economic factors. Results indicate the great suitability of harmonized Landsat 8 and Sentinel-2 images to distinguish multiple trajectories of cropland abandonment in subtropical mountainous areas. Our framework of mapping cropland abandonment resulted in good producer's (78.2%) and user's (81.3%) accuracies. The statistical analysis showed 31.85% of croplands cultivated in 2000 were abandoned by 2018, and more than a quarter of townships experienced cropland abandonment with high abandoned rates (>38%). Cropland abandonment mainly occurred in relatively unfavorable areas for agricultural production, for instance with a slope above 6°. Slope and the proximity to the nearest settlement explained 65.4% and 8.1% of the variation of cropland abandonment at the township level, respectively. The developed approaches on both mapping cropland abandonment and modeling determinants can be highly relevant to monitor multiple trajectories of cropland abandonment and ascribe their determinants not only in mountainous China but also elsewhere and thus promote the formulation of land-use policies that aim to steer cropland abandonment.

Exposure of ambient PM2.5 during gametogenesis period affects the birth outcome: Results from the project ELEFANT.

Various environmental and behavioural factors influence neonatal health. Gamete formation (gametogenesis) is a crucial period which affects embryo development and neonatal health and ambient air pollution exposure at this stage may lead to an adverse birth outcome. Previous epidemiological and toxicological research demonstrated a strong association between maternal ambient air pollution exposure and adverse birth outcomes. However, the joint exposure-outcome of paternal exposure (76 days before the last menstruation and 14 days after the last menstruation) and maternal exposure (14 days after the last menstruation) when exploring the mechanism of the influence of air pollutants on pregnancy outcome and neonatal health remains unexplored. Here, in the Project Environmental and LifEstyle FActors iN metabolic health throughout life-course Trajectories (ELEFANT), we collected the data of 10,960 singleton pregnant women with 24-42 completed gestational weeks and included them in this study. A multinominal logistic regression model was applied to investigate the association between adverse birth outcomes and ambient PM2.5 exposure levels during spermatogenesis and oogenesis. Results from the binary classification of ambient PM2.5 exposure showed that the risk of abnormal birthweight was significantly greater when ambient PM2.5 exposure was both higher during spermatogenesis and oogenesis, with RRs of 1.86 (95% CI: 1.02, 3.39). The risk of macrosomia (RR: 1.88 (95% CI: 1.13, 3.12)) increased significantly when ambient PM2.5 levels were higher during spermatogenesis. Primiparity and primigravity are more likely to be influenced by higher ambient PM2.5 levels during spermatogenesis. In conclusion, more attention should be paid to higher exposure level of ambient PM2.5 during spermatogenesis.

Multi-scale variations and impact factors of carbon emission intensity in China.

China's carbon emissions have developed swiftly in recent decades, which will not only affect the nation's own sustainable development, but have a potentially negative impact on global climate stability. Given that socioeconomic development is susceptible to regional heterogeneity and geographic scales, a systematic exploration of spatiotemporal variations of carbon emission intensity (CEI) and their drivers across different levels is conducive to enacting more reasonable and efficient measures for emission reduction. However, there is still a lack of comprehensive analysis of these issues. In this paper, we attempted to quantify and compare the spatiotemporal evolution and spatial spillover effects of impact factors on CEI from nighttime light imagery and socioeconomic data at two China's administrative levels by utilizing the variation coefficient, spatial autocorrelation model and spatial econometric methods. The results showed that the spatiotemporal variations of CEI were greater at the prefecture level compared to the provincial level during 2000-2017. There were significant positive spatial autocorrelation of CEI at two administrative levels, and self-reinforcing agglomeration was more substantial at the prefectural level than that provincial level. While the local spatial clustering of CEI of each administrative level altered with scale dependence, the binary spatial structure (High-High and Low-Low) of CEI remained relatively steady in China. Various driver factors not only had direct effects on local CEI, but had spatial spillover effects on neighboring areas. Our findings illustrate that China's CEI is sensitive to the space-time hierarchy of multi-mechanisms, and suggest that "proceed in the light of local conditions" strategies can assist the Chinese government for CEI mitigation.

Association between exposure to earthquake in early life and diabetes mellitus incidence in adulthood with the modification of lifestyles: Results from the Kailuan study.

Background: Exposure to disasters in early life may induce lifetime health risk, but investigation on earthquake exposure and DM in later life is still limited. The aim of the current study is to evaluate the association between exposure to the Tangshan Earthquake in early life and diabetes mellitus (DM) incidence in adulthood, and explore the modification of lifestyles on DM development. Methods: Participants who were free of DM at baseline from the Kailuan Study were included in this study. All participants were divided into fetal-exposed, infant-exposed, early childhood-exposed and nonexposed group. The effect of earthquake exposure on DM and modification of lifestyles were examined by multivariable-adjusted Cox proportional hazard model. Results: The exposed group had a higher risk of DM than nonexposed group, especially in infant-exposed and early childhood-exposed group, with hazard ratio (HR) of 1.62 [95% confidence intervals (CI), 1.21-2.17] and 1.46 (95% CI, 1.06-1.99), respectively. After stratifying by lifestyles, a significant modification was observed in alcohol consumption. Conclusion: Exposing to earthquake in early life could increase DM incidence in later life, and alcohol consumption might modify the effect of earthquake exposure on DM development. More attention should be paid on the preventions of DM among adults who exposed to earthquake in their early life.

Dexmedetomidine Combined with Femoral Nerve Block Provides Effective Analgesia Similar to Femoral Nerve Combined with Sciatic Nerve Block in Patients Undergoing Total Knee Arthroplasty: A Randomized Controlled Study.

BACKGROUND: Total knee arthroplasty (TKA) is a severe traumatic procedure, and femoral nerve block (FNB) combined with a sciatic nerve block (SNB) is widely used in TKA. However, injury of the sciatic nerve is clinically reported. Dexmedetomidine (DEX) could reduce stress and inflammation, as well as improve pain in TKA. This study aims to observe the analgesic impact of DEX combined with FNB in TKA. METHODS: Eighty-eight patients undergoing TKA were included and randomly divided into two groups: DF group (FNB combined with DEX 0.6µg/kg before surgery, followed by DEX 0.2-0.4µg/kg/h until articular closure) and SF group (FNB combined with SNB). Each nerve was blocked with 0.375% ropivacaine 20mL, and all patients received general anesthesia routinely. The primary endpoint was the pain visual analog scale (VAS) score during activities at postoperative 24 hours. RESULTS: There was no statistical difference in the pain VAS scores at any time point. The mean duration of analgesia for patients with rescue analgesic requests was comparable between the two groups: 25.4 ± 6.3 hours in the DF group vs 24.8 ± 6.4 hours in the SF group (two-sample t-test, p=0.738). The total dose of sufentanil was similar between groups (P=0.355). The maintenance dose of propofol and dose of rescue analgesics were comparable (all P>0.05). There were no statistical differences in the incidence of adverse events. However, the time to extubate in the DF group was significantly longer than those in the SF group (P<0.001). CONCLUSION: DEX combined with FNB could provide effective analgesia similar to SNB combined with FNB in TKA. CLINICAL TRIAL REGISTRATION: The trial was registered at the Chinese Clinical Trial Registry on November 17, 2019 (identifier: ChiCTR1900027552).

Implications of land sparing and sharing for maintaining regional ecosystem services: An empirical study from a suitable area for agricultural production in China.

The clarification of land use management in areas of potential land use conflict plays an important role in maintaining ecosystem services. However, the relationship between land use strategies and ecosystem services in potential conflict zones remains uncertain, lacking quantitative evidence. Therefore, to construct a healthy territorial space system, a spatial classification model for land use was built based on land sparing and sharing. In addition, the inherent characteristics of different modes in the landscape structure and functional heterogeneity were also resolved. Then, an empirical analysis was carried out with the coastal agricultural production area of Maoming City, Guangdong Province. Focusing on the potential area of land use conflicts in Maoming City, that is, the suitable area for agricultural production, this study determined the differences in ecosystem services under multiple land use patterns at the pixel level, explored the trade-offs of ecosystem services in the entire suitable area and a single model, and examined the gradient effect of ecosystem services with the intensity of cultivated land use. According to the results, ecosystem services significantly differed in land use patterns, and the comprehensive ecosystem service was the highest in the land sharing model. Ecosystem services exert a synergistic effect in the entire suitable area for agricultural production, whereas there exists no correlation within a single model. When the arable land area of intensive agriculture exceeds 84.84%, food supply and other ecosystem services will be reduced to varying degrees. The study bridges the gap in research on the relationship between land sparing and sharing and ecosystem services in Chinese regions, and proposes clear land remediation strategies in potential conflict zones, which can thus provide some guidance for achieving sustainable regional development.

Effect of Different Modes of Administration of Dexmedetomidine Combined with Nerve Block on Postoperative Analgesia in Total Knee Arthroplasty.

INTRODUCTION: Dexmedetomidine (DEX) as a nerve block adjuvant can significantly prolong analgesia. However, whether perineural or systemic administration of DEX is more beneficial in patients undergoing total knee arthroplasty (TKA) has not been thoroughly investigated. To this end, we evaluated the effects of perineural and systemic DEX administration on postoperative analgesia in patients undergoing TKA surgery. METHODS: We randomly assigned patients undergoing TKA under general anesthesia combined with femoral nerve block and sciatic nerve block to one of three groups: (1) ropivacaine plus perineural dexmedetomidine (DP): 0.25% ropivacaine 40 mL plus 0.5 µg/kg dexmedetomidine; (2) ropivacaine plus systemic dexmedetomidine (DS): 0.25% ropivacaine 40 mL plus systemic 0.5 µg/kg dexmedetomidine; (3) control group (C): 0.25% ropivacaine 40 mL. RESULTS: The average length of time until patients first experienced postoperative pain was significantly longer in the DP group (26.0 h [22.0-30.0 h]) than in the DS group (22.4 h [18-26.8 h]) and the control group (22.9 h [19.5-26.3 h], P = 0.001). For this result there was no significant difference between the DS and the control group. Compared with the DS and control groups, patients in the DP group had lower resting visual analogue scale (VAS) scores at 24, 48, and 72 h after surgery (P < 0.05). VAS activity scores at 12, 24, and 48 h after surgery in the DP group were lower than those in the DS and control groups, with a statistically significant difference (P < 0.05). Compared with the DS and control groups, the amount of postoperative opioids in the DP group was also significantly reduced, and the number of people needing postoperative rescue analgesia was significantly lower, with a statistical difference (P < 0.05). Meanwhile, the sleep satisfaction of patients in the DP group on the first night after surgery and the satisfaction with pain control at 72 h after surgery were both higher than those in the DS group and control group (P < 0.05). CONCLUSIONS: Perineural administration of DEX can significantly prolong the interval until patients report pain for the first time after TKA, relieve postoperative pain, reduce postoperative opioid dosage, and improve postoperative sleep quality and satisfaction with pain control. TRIAL REGISTRATION: The trial was registered at the Chinese Clinical Trial Registry, identifier ChiCTR1900025808.

Estimating Short- and Long-Term Associations Between Air Quality Index and COVID-19 Transmission: Evidence From 257 Chinese Cities.

Objectives: To evaluate the long- and short-term effects of air pollution on COVID-19 transmission simultaneously, especially in high air pollution level countries. Methods: Quasi-Poisson regression was applied to estimate the association between exposure to air pollution and daily new confirmed cases of COVID-19, with mutual adjustment for long- and short-term air quality index (AQI). The independent effects were also estimated and compared. We further assessed the modification effect of within-city migration (WM) index to the associations. Results: We found a significant 1.61% (95%CI: 0.51%, 2.72%) and 0.35% (95%CI: 0.24%, 0.46%) increase in daily confirmed cases per 1 unit increase in long- and short-term AQI. Higher estimates were observed for long-term impact. The stratifying result showed that the association was significant when the within-city migration index was low. A 1.25% (95%CI: 0.0.04%, 2.47%) and 0.41% (95%CI: 0.30%, 0.52%) increase for long- and short-term effect respectively in low within-city migration index was observed. Conclusions: There existed positive associations between long- and short-term AQI and COVID-19 transmission, and within-city migration index modified the association. Our findings will be of strategic significance for long-run COVID-19 control.

Effects of Different Local Analgesic Techniques on Postoperative Quality of Life and Pain in Patients Undergoing Total Hip Arthroplasty Under General Anesthesia: A Randomized Controlled Trial.

BACKGROUND: Both lumbosacral plexus block (LSPB) and local infiltration analgesia (LIA) can provide postoperative analgesia for patients undergoing total hip arthroplasty (THA). The current study aimed to compare the differences between LSPB and LIA on postoperative pain and quality of life (QoL) in THA patients. METHODS: A total of 117 patients aged 40-80 years, ASA I-III, were prospectively randomized into two groups: a general anesthesia plus LSPB (Group LSPB) and a general anesthesia plus LIA (Group LIA). Pain intensity and opioid consumption were recorded Within 72 hours after surgery. QoL was measured by EQ-5D and EQ-VAS questionnaires, and the incidence of postoperative pain was measured as part of the EQ-5D on day 1, day 3, day 7, and month 1, month 3, and month 6 after surgery. RESULTS: EQ-5D scores: Mobility, Self-Care, Usual Activities, Pain/Discomfort, and Anxiety/Depression were higher in Group LSPB versus Group LIA throughout six-month follow-ups (p = 0.039). The pain intensity was lower in Group LSPB than in Group LIA 0-12 h after surgery (2.41 vs 2.79, p = 0.01), but was higher in Group LSPB than in Group LIA 12-24 h (2.59 vs 2.05, p = 0.02) and 24-48 h (2.18 vs 1.73, p = 0.02) after surgery. There were no differences in opioid consumption between the groups during the first 72 postoperative hours. In the first month after surgery, more patients in Group LSPB than in Group LIA had no pain (52 vs 40, p = 0.04). CONCLUSION: Both LSPB and LIA can provide satisfactory postoperative analgesia. The LSPB is better than LIA for long-term QoL in THA patients undergoing general anesthesia. CLINICAL TRIAL REGISTRATION NUMBER: The Chinese Clinical Trial Registry (ChiCTR-INR-17012545).

Spatial identification and determinants of trade-offs among multiple land use functions in Jiangsu Province, China.

Understanding the relationships among multiple land use functions (LUFs) is crucial for land-based spatial planning that can guide targeted land use policy-making in complex socio-ecological systems. However, few studies concerned the interactions among various LUFs integrating the issues of economy, environment, and society at a fine scale. In this study, we quantified 12 LUFs using a geospatial model and statistical analysis at the grid scale in Jiangsu Province. Then, we identified the relationships among three primary LUFs-agricultural production function (APF), urban-rural living function (ULF), and ecological maintenance function (EMF)-and further explored the determinants of LUF trade-offs aimed to provide a reference for policy-makers to make decisions in future land use planning and management. The results revealed that the high trade-off areas for APF and ULF are mainly distributed in central and northern Jiangsu, and the trade-offs for both APF-EMF and ULF-EMF were higher in the area covered with water and forest. The determinants of LUF trade-offs mainly refers to land use/land cover, potential evapotranspiration, and vegetation coverage ratio. Moreover, landscape configuration metrics and distance to the nearest county and nearest road also have remarkable impacts on the trade-offs of APF-EMF and ULF-EMF. Finally, we proposed that the concepts of LUF trade-offs should be incorporated into the processes of delineating boundaries for urban growth, farmland, and natural areas. We also propose that land consolidation projects should be implemented in an orderly manner to alleviate LUF trade-offs.

A research framework of land use transition in Suzhou City coupled with land use structure and landscape multifunctionality.

Under the premise of facing land-use sustainable development goals, clarifying the process and trend of regional land-use transition (LUT) is of considerable significance to the direction of national land-use optimization in the future. Suzhou City is not only an economically developed area in China but also a leading area of economic transformation and development, which embodies the changing process of regional development path since China's reform and opening up. This paper constructed an integrated research framework of micro-individual land use structure and macro-mixed landscape multifunctionality. It used spatial analysis technology to deeply analyze the LUT process of Suzhou, and quantified change characteristics of land use structure and function in Suzhou from 2000 to 2015. For structure, Suzhou has undergone a large-scale transition during the study period, mainly from farmland to construction land, in which transition speed and degree are at a high level until the trend slows down after 2010. For function, the number of high values of landscape multifunctionality gradually increases. Still, the scope of high-value areas progressively reduces by urban expansion constraints; the multifunctionality around urban expansion area gradually weakens. Besides, forest land, grassland, and other ecological land have the most significant number of land use functions. The comprehensive transition of land use structure and function can give a summary as a circle-layer dynamic change process of urban development. Transition hotspots can be divided into five specific regions of land management and finally realize comprehensive development zoning of urban and rural areas at the township level. LUT research framework based on structure-function coupling will provide ideas for land management mode transformation and contribute to sustainable land spatial planning strategy formulation.

A framework for assessing carbon effect of land consolidation with life cycle assessment: A case study in China.

Ecological transformation is an inevitable trend for the development of land consolidation (LC) worldwide, and the research on carbon effect of LC is an important theoretical basis for promoting the construction of Eco-LC. However, there is currently a lack of analysis of the carbon effect based on the whole process of LC, ignoring the stage elements and temporal factors. This study applied Life Cycle Assessment (LCA) method to construct a research framework and accounting system for carbon footprint assessment of LC, and explored the carbon effect in a typical land consolidation project area (LCPA) of China. Results showed that: (a) The carbon effect of the project area was characterized as carbon emission during the whole life cycle of LC. Carbon footprint before and after LC was 3.251 tCE·ha-1·a-1 and 2.401 tCE·ha-1·a-1 respectively. The carbon storage reduced and the carbon footprint is declined by 0.850 tCE·ha-1·a-1. (b) Carbon effect varied among different stages of LC. The Benefit Period (BP) was the only stage that was manifested as carbon absorption (-14.65%), while all the other stages were manifested as carbon emission. Among them, as to the carbon emission, the Construction Period (CP) played a decisive role with the most proportion (102.74%), followed by DP and RP, and the carbon effect of PP was negligible. (c) The dominant factors of carbon effect at different stages were also different. During CP, cement contributed the most to the carbon emission in this case. During RP, carbon sequestration effect of cropland proved to be the most significant. During RP, the carbon sequestration effect of cultivated land and the carbon emission effect of unused land were the most prominent. During BP, the carbon sequestration capacity of farmland ecosystems proved to be greater than the carbon emissions from agricultural activities. This study contributes to providing certain theoretical guidance and method reference for the realization of Low-Carbon LC project planning, with this comprehensive and reliable method.

A new framework of land use efficiency for the coordination among food, economy and ecology in regional development.

Great challenges regarding land use conflicts in rapid urbanization call for deeper research on land use efficiency (LUE) from the perspective of sustainable land use for the coordination among food security, economic development, and ecological protection. This study firstly develops a new framework of LUE based upon the expectations in land use and the coordination among three sub-categories in food production, economic development, and ecological protection, then, uses the coupling coordination degree model to quantify the spatial differentiation characteristics and coupling coordination relationships among three sub-categories, and finally uses the multivariable linear regression and geographical detectors to analyze the impact factors of sub-category efficiency. The framework is applied to Jiangsu Province in eastern China by using ten indicators (i.e., cultivated land quality, grain output, multiple cropping index, average GDP per km2, population density, proportion of industry and service industry, vegetation cover index, water conservation index, soil retention index, and carbon sequestration index) in terms of food production, economy, and ecology analysis at the county level. Compared with expectations, the LUE of Jiangsu in food production, economic development, and ecological protection is 54.15%, 85.56%, and 54.95%, respectively, indicating that Jiangsu has great potential for sustainable land use. The coupling coordination degree in land use generally synchronizes with the coupling degree, accounting for 65.34% of the province's area, of which 75.00% are in lower-coupling & lower-coordination, medium-coupling & medium-coordination. Among all the factors, proportion of industry and service industry, population density, multiple cropping index, average GDP per km2, and water conservation index have the most important roles in the coordinated development of land use sub-systems. Therefore, we suggest land use/urban management need to implement more integrated planning and differentiated strategies to stimulate land use potential and maintain efficient and sustainable land use.

The historical process of the masonry city walls construction in China during 1st to 17th centuries AD.

Masonry city walls were common defense facilities in the cities of the Eurasian before the industrial revolution. However, they were not widespread in China until the Ming Dynasty (1368-1644). Limited in research methods, previous studies failed to make convincing arguments on this phenomenon. We collected, organized and analyzed relevant historical documents to reconstruct the spatio-temporal process of the construction of masonry walls from 1st to 17th century in China. We conducted a time series analysis primarily based on factors such as wars, garrisons, economy, and natural disasters. Analysis of the correlation among the construction of masonry walls and these factors provides insights into this process. From the 1st to 14th century, only 125 masonry city walls were built in China and the annual average number was below 0.1. While in the Ming Dynasty, a total of 1,493 masonry walls were built, with an annual average of 5.41. The construction activities in 1368-1456 spread throughout the country, but mainly appeared in the high-grade administrative cities and garrisons, as a result of the planned implementation of the central government. The construction activities in 1457-1644 had corresponding cluster areas during different periods, mainly at county-level. We found that the wall construction was stimulated by external factors such as wars and disasters. We believe that the mass construction of masonry walls in the Ming Dynasty is a phenomenon of cultural diffusion. The central government plan, the complex interactions between local governments and community, and the stimulation of external factors worked together to contribute to the diffusion of masonry city walls in the Ming Dynasty.

Satellite data indicates multidimensional variation of agricultural production in land consolidation area.

Land consolidation (LC) is an innovative way to improve agricultural production. Spatiotemporal pattern of agricultural production in land consolidation area (LCA) is difficult to quantify with limited field observations and survey data. Satellite data has advantages on recording vegetation status changes frequently, which is very supportive of estimating variation of agricultural production. In this paper, we used Net Primary Productivity (NPP), Normal Difference Vegetation Index (NDVI), and Multiple Band Drought Index (MBDI) from satellite data, to examine five attributes (irrigation capacity, multiple cropping index, crop phenology, farmland productivity, and production stability) of agricultural production after land consolidation (LC) at a site in China. Results show that there were no significant spatial differences in irrigation capacity for farmland in few years after LC due to consistent climatic conditions and uniform irrigation and drainage system. Multiple cropping index shows a pattern of "first reducing, then growing, last reducing", which may result from the disturbed "water-soil" environment and weak farmers' intention. Interannual variation of spatial distribution of phenology for the second-season crop is larger than that for the first-season crop since LC implementation adjusts short-term land use and management. With the improvement of production conditions and balanced distribution of production elements, farmland productivity has been improved and its differences among various farmland patches imply a reducing trend. Production in LCA is slightly less stable than that in the control area (TCA) where LC is not carried out because of limited and short-term effect from LC. We concluded that satellite data presents variation of agricultural production in LCA from different dimensions of time, space and attributes. Multidimensional variation of agricultural production is decided by several factors, including climate condition, LC activity, and farmers' intention.

Spatial identification and dynamic analysis of land use functions reveals distinct zones of multiple functions in eastern China.

Land use function (LUF) is a valuable concept that allows for more integrated assessments of land system change. Identifying the changes and relationships of multiple LUFs is pertinent to land use planning and management. Selection and quantification of LUF indicators are critical for LUFs assessment. However, past studies have mostly assessed LUFs using socioeconomic data, which are not suitable for spatial variable quantification. In this study, we proposed a new LUFs classification system based on spatial planning goals, and we applied the system to assess 12 LUFs across 63 counties in Jiangsu Province of eastern China based on multi-source data using geospatial modeling tools combined with statistical analysis of socioeconomic data. We also analyzed the change in LUFs between 2000 and 2015, as well as the interactions among multiple functions. Finally, we identified distinct function zones based on the LUFs assessment in 2000 and 2015 using k-means clustering. The result showed that 12 LUFs displayed significant changes and interactions between 2000 and 2015, which can be explained by differing topography and social-ecological characteristics among counties. Additionally, we found four distinct LUF zones that are spatially agglomerated in similar landscapes and characterize specific LUF relationships in each cluster. In the future, local LUFs and their changes over time should be taken into consideration for land use planning and management, which provide a reference for policy-makers to make decisions that better match local development realities.

Evaluating and predicting the effectiveness of farmland consolidation on improving agricultural productivity in China.

Food security has always been a focus issue in China. Farmland consolidation (FC) was regarded as a critical way to increase the quantity and improve the quality of farmland to ensure food security by Chinese government. FC projects have been nationwide launched, however few studies focused on evaluating the effectiveness of FC at a national scale. As such, an efficient way to evaluate the effectiveness of FC on improving agricultural productivity in China will be needed and it is critical for future national land consolidation planning. In this study, we selected 7505 FC projects completed between 2006 and 2013 with good quality Normalized Difference Vegetation Index (NDVI) as samples to evaluate the effectiveness of FC. We used time-series Moderate Resolution Imaging Spectroradiometer NDVI from 2001 to 2013, to extract four indicators to characterize agricultural productivity change of 4442 FC projects completed between 2006 and 2010, i.e., productivity level (PL), productivity variation (PV), productivity potential (PP), and multi-cropping index (MI). On this basis, we further predicted the same four characteristics for 3063 FC projects completed between 2011 and 2013, respectively, using Support Vector Machines (SVM). We found FC showed an overall effective status on improving agricultural productivity between 2006 and 2013 in China, especially on upgrading PL and improving PP. The positive effect was more prominent in the southeast and eastern China. It is noteworthy that 27.30% of all the 7505 projects were still ineffective on upgrading PL, the elementary improvement of agricultural productivity. Finally, we proposed that location-specific factors should be taken into consideration for launching FC projects and diverse financial sources are also needed for supporting FC. The results provide a reference for government to arrange FC projects reasonably and to formulate land consolidation planning in a proper way that better improve the effectiveness of FC.