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Coastal reclamation has been used widely to accommodate urbanization and support increasing food demand. However, the responses of soil properties and soil-related ecosystem services (SES) to reclamation remain unclear. There are no effective operational methods for calculating the SES provided by reclaimed cropland. Using field sampling data of soil properties, we proposed a framework to evaluate the influence of reclamation on the soil's ability to provide five SESs: plant growth support (SES1), carbon storage (SES2), nutrient cycling (SES3), erosion control (SES4), and habitat provision (SES5). A series of SES indices were constructed accordingly and tested using data from a reclaimed soil chronosequence over 700 years in Hangzhou Bay, China. The results showed that all the SES indices increased significantly along the reclamation chronosequence, with the highest impact for SES2 (273.7% of soil C storage growth) owing to long-term continuous cultivation and fertilization. Most of the indices have a different logarithmic relationship with reclamation time, with a faster growth rate in the first 50 years, while SES1 increases linearly with reclamation time. Using soil organic matter as a reference, the sensitivity of SESs to reclamation is SES4 > SES2 > SES5 > SES3 > SES1. The significant positive correlations between all SES indices suggest that the provision of the five SESs is interdependent, with strong synergy. Our methods and index system can be effectively used to monitor coastal cropland protection and promote sustainable management of reclaimed land. • A framework was proposed to assess the impact of coastal reclamation on soil-related ecosystem services (SES). • Soil properties and SES were analyzed in a chronosequence of coastal reclamation. • SES increased with reclamation time in Hangzhou Bay. • Significant positive correlations between SESs indicated they have strong synergies. [ABSTRACT FROM AUTHOR]

Abstract Land use change under rapid urbanization can drastically change terrestrial ecological conditions. This study presents an integrated analysis of land use dynamics and the resultant ecological impacts on sustainable development over the past 25 years (1990–2015) in response to urban development. Remote sensing and geographic information system techniques were employed to examine the spatiotemporal trajectory of land use changes. Based on the analysis of the equivalent factor table for land use types and ecosystem services value (ESV), the value of ecosystem services was calculated in the case study of Fuyang, China. Correlations were identified between ESV and a family of landscape fragmentation metrics. The results showed that the area affected by land use changes represented 33.35% of the total study area and caused a 31.74 million US$·a−1 decrease in ESV from 1990 to 2015. The ESV was spatially imbalanced and generally low in urban areas. Ecological plans for cropland reforestation and urban green projects were effective in slowing ESV losses while urban areas rapidly developed. In addition, total ESV was negatively correlated with edge density (ED), patch density (PD), landscape shape index (LSI), and Shannon's diversity index (SHDI) but positively correlated with aggregation index (AI), suggesting that landscape fragmentation had an adverse impact on the overall ESV in Fuyang. Therefore, sustainable land use planning must be integrated with landscape patterns to provide useful guidance regarding the spatial regulation of a given area to protect and improve ecosystem services. Graphical abstract Unlabelled Image Highlights • Land use changes and their consequence on ecosystem services value (ESV) and landscape fragmentation was identified. • Ecological protection plans showed effectiveness in slowing ESV losses while urban rapidly developed. • Landscape fragmentation was proved to have an adverse impact on ESV. [ABSTRACT FROM AUTHOR]

Land suitability analysis is an important step in land use planning for livestock development because of its high efficiency to allocate livestock farms to the most suitable land areas and minimize adverse effects on environment. This study aimed to use two multi-criteria analysis approaches: Weighted Linear Combination (WLC) and Ordered Weighted Averaging (OWA), to comparatively evaluate and map land use suitability for livestock production in Hangzhou metropolitan area, China. The evaluation used eight factors as suitability criteria, relating to topographic, environmental, human factors, and socio-economic data. The analytic hierarchy process (AHP) method and GIS techniques were integrated into the evaluation models to create the land suitability map. The results of WLC approach showed that 11.4% of the total area was highly suitable for livestock production while 48.6% was unsuitable. Of these, areas located far from central city had higher suitability, while areas close to the urban district, drinking water source area, ecological and natural conservation area, had lower suitability. Sensitivity analysis indicated this expert suitability results for livestock production were robust. Indirect validations conducted by mutual comparisons of suitability maps computed using the WLC and OWA approaches demonstrated 90.4% of the overall agreement with a kappa coefficient of 0.857, indicating that both methods provide very similar spatial land use suitability distributions. Ecological fitness was evaluated by comparing the suitability analysis result with a previous livestock development planning and several recommendations aimed at improving the long-term livestock development plans were made for Hangzhou. [ABSTRACT FROM AUTHOR]

• The island development of functional polycentricity was lagging than that of the morphological dimension. • Spatial regression model performs well in fitting the association between polycentric urban variables and island landscape changes. • The effects of dual polycentric urban indicators on island landscape changes varied spatially and temporally. • Polycentric urban development generally contributed to fragmented and complex island landscape patterns on the periphery areas of subcenters and reclamation. Polycentric urban development has become popular worldwide as expected to generate greater agglomeration externality and facilitate socioeconomic achievements. Despite much insightful work on urban polycentricity in coastal agglomerations or megacities, few studies have focused on how polycentric urban development affects landscape sustainability in vulnerable island cities. This paper characterized the urban polycentricity from the perspective of morphological and functional dimensions during 1990–2020 in Yuhuan island city, China, and quantified the association between polycentric urban variables and island landscape changes by spatial regression. The results showed that there was a mismatch in development between the morphological and functional polycentricity, in which the functional dimension was lagging. In response, island landscape patterns became fragmented and scattered. With the application of GWR models, the effects of two polycentric factors on island landscape changes varied spatially and temporally. The stronger relationships between them were identified in regions where more heterogeneous patterns were presented, such as the subcenters and their surroundings and reclamation areas. These trends were mainly attributed to industrial suburbanization and the development of new economic zone and Damaiyu port. Our findings call for a more balanced functional urban polycentricity; and local-specific landscape effects should be scheduled in island planning practice and sustainable development. [ABSTRACT FROM AUTHOR]

• People are more exposed to street greenery than to parks. • The Green View Index (GVI) is used to quantify the daily exposure to street-side greenery. • Development of a multidimensional indicator set to explore the association of the micro-scale surrounding environment characteristics and GVI. • The context surrounding environment exhibits a strong role on physical appearance of eye-level greenness of GVI. • Findings can shed lights on developing urban green design and planning policy. Human-scale greenery has been heavily featured in the development of planning-related theories and research. Daily exposure to street greenery is proportionately greater than exposure to parks. Several case studies have estimated the green view index (GVI), which quantifies daily exposure to street-side greenery, at the city-scale. However, the street-side greenery distribution is uneven. The relationship between the GVI and the surrounding environment has rarely been discussed. Here, we investigate the differentiation of street greenery from the physical features of a street and examine how the surrounding environment affects the physical appearance of eye-level greenery. In this work, we analyzed the GVI using the internet data crawling approach and obtained 12,232 panoramic street view images from Baidu Map for the urban zones of Hangzhou, China. A range of 17 surrounding environmental characteristics are integrated with multisource geographic data to analyze their relationship with the GVI at the microscale. Spatial econometric models are explored to provide insights into the underlying mechanisms associated with the GVI. The results showed that the surrounding environment exhibited a strong role in the physical appearance of eye-level greenness. There are two pathways through which surrounding environmental characteristics (the nature of land use and the enclosure of the street) affect the distribution of GVI. Four factors proved to be important: scenic protection policies and ecological renewal projects, vertical and horizontal green characteristics of different land uses, and facade designs dominated by enclosed exterior walls or railing walls. Interesting approaches are presented to rationally implement activities related to these factors. The urban green design process should be facilitated in terms of the trade-off between greenery and optimum land use. These findings can be useful in drafting appropriate policies and increasing eye-level greenery in cities. [ABSTRACT FROM AUTHOR]

Soil cadmium (Cd) contamination has attracted a great deal of attention because of its detrimental effects on animals and humans. This study aimed to develop and compare the performances of stepwise linear regression (SLR), classification and regression tree (CART) and random forest (RF) models in the prediction and mapping of the spatial distribution of soil Cd and to identify likely sources of Cd accumulation in Fuyang County, eastern China. Soil Cd data from 276 topsoil (0–20 cm) samples were collected and randomly divided into calibration (222 samples) and validation datasets (54 samples). Auxiliary data, including detailed land use information, soil organic matter, soil pH, and topographic data, were incorporated into the models to simulate the soil Cd concentrations and further identify the main factors influencing soil Cd variation. The predictive models for soil Cd concentration exhibited acceptable overall accuracies (72.22% for SLR, 70.37% for CART, and 75.93% for RF). The SLR model exhibited the largest predicted deviation, with a mean error (ME) of 0.074 mg/kg, a mean absolute error (MAE) of 0.160 mg/kg, and a root mean squared error (RMSE) of 0.274 mg/kg, and the RF model produced the results closest to the observed values, with an ME of 0.002 mg/kg, an MAE of 0.132 mg/kg, and an RMSE of 0.198 mg/kg. The RF model also exhibited the greatest R2 value (0.772). The CART model predictions closely followed, with ME, MAE, RMSE, and R2 values of 0.013 mg/kg, 0.154 mg/kg, 0.230 mg/kg and 0.644, respectively. The three prediction maps generally exhibited similar and realistic spatial patterns of soil Cd contamination. The heavily Cd-affected areas were primarily located in the alluvial valley plain of the Fuchun River and its tributaries because of the dramatic industrialization and urbanization processes that have occurred there. The most important variable for explaining high levels of soil Cd accumulation was the presence of metal smelting industries. The good performance of the RF model was attributable to its ability to handle the non-linear and hierarchical relationships between soil Cd and environmental variables. These results confirm that the RF approach is promising for the prediction and spatial distribution mapping of soil Cd at the regional scale. [ABSTRACT FROM AUTHOR]

• Coastal reclamation in Hangzhou Bay from 1985 to 2015 were explored. • Land reclamation has greatly degraded ecosystem service value of coastal wetlands. • Economic gain failed to compensate for ecosystem service value loss in coastal reclamation. • The strict prohibition on coastal reclamation poses a big challenge to local governments. Due to the growing demand for land resources, coastal reclamation has become a global land use practice. Although the reclamation of coastal wetlands brings substantial economic benefits, it can lead to a series of adverse ecological impacts. Considerably, economic and ecological trade-offs of reclamation activities must be analyzed to make targeted land use policy decisions. This study focuses on land reclamation on the east coast of China, taking Hangzhou Bay as a case study. Remote sensing techniques were used to detect the coastline and landscape changes in the reclaimed areas from 1985 to 2015. Subsequently, field surveys and empirical parameters were employed to evaluate the impact on coastal ecosystem services. Finally, the monetary analysis was used to evaluate the trade-offs between ecological loss and economic gain due to land reclamation. The results showed that a total of 75134.3 ha of coastal wetlands (accounting for 8.58% of the total land area) were reclaimed from 1985 to 2015 in the Hangzhou Bay. A substantial decline in ecosystem service value (ESV) was observed with a drop from 866,400 Yuan ha−1 in 1985 to 285,800 Yuan ha−1 in 2015 due to the conversion of natural to artificial landscape. The total ESV loss exceeded the economic benefits throughout the study period, thus the economic benefits failed to compensate for the ESV loss. This trade-off relationship resulted from reclamation expansion on short-term economic benefits at the expense of long-term ecological value. According to these findings, we propose three main ways to achieve a "win–win" situation between gains and loss of reclamation for sustainability. [ABSTRACT FROM AUTHOR]

Agricultural land fragmentation has an important impact on ecosystem services, especially food production. However, the relationship between land fragmentation and production diversification remains controversial and requires further analysis. This study characterized the dynamics of land fragmentation and production diversification in Zhejiang Province, China, from 1995 to 2015 using remote sensing, landscape metrics, and a diversification assessment approach. The results showed that Zhejiang Province experienced increasing fragmentation of agricultural landscapes and profound diversification of agricultural production. Fragmentation had a significant negative effect on grain crop production, but it had a significant positive effect on production diversification. These findings showed that fragmentation is an important driver of the diversification of agriculture and contributes to increased dietary diversity in local households. Therefore, we believe that when addressing land fragmentation issues, both the positive and negative impacts of fragmentation in different local conditions and circumstances should be taken into account. Our findings will provide scientific support for land consolidation management and agricultural land resource protection. [ABSTRACT FROM AUTHOR]

Rapid urbanization in China has led to an increasing problem of atmospheric nitrogen dioxide (NO2) pollution, which negatively impacts urban ecology and public health. Nitrogen dioxide is an important atmospheric pollutant, and quantitative spatio-temporal analysis and influencing factor analysis of Chinese cities can help improve urban air pollution. In this study, the spatio-temporal analysis methods were used to explore the variations of NO2 pollution in Chinese cities from 2005 to 2020. The findings are as follows. In more than half of Chinese cities, NO2 levels remarkably decreased between 2005 and 2020. The effective NO2 reduction strategies contributed to the significant NO2 reduction during the 13th Five-Year Plan (2016–2020). Moreover, we found that the pandemic of COVID-19 alleviated NO2 pollution in China since it reduced the traffic, industrial, and living activities. The NO2 pollution in Chinese cities was found highly spatially clustered. The geographically and temporally weighted regression model was used to analyze the spatio-temporal heterogeneity of NO2 pollution influencing factors in Chinese cities, including natural meteorological and socio-economic factors. The results showed that the GDPPC, population densities, and ambient air pressure were positively correlated with NO2 pollution. In contrast, the ratio of the tertiary to the secondary industry, temperature, wind speed, and relative humidity negatively impacted the NO2 pollution level. The findings of this research contribute to the improvement of urban air quality, stimulating the achievements of the sustainable development goals of Chinese cities. [ABSTRACT FROM AUTHOR]