Search Results (12)

Land use/cover change (LUCC) is a vital aspect representing global change and humans’ impact on Earth’s surface. This study utilized the ESRI Land Cover 2020 and China Land Cover Dataset (CLCD), along with historical imagery from Google Earth, to develop a method for the assessment of land use data quality. Based on the assessment, the CLCD was updated to generate an improved Re-CLCD for the Pan-Pearl River Basin (PPRB) from 1985 to 2020, and to analyze LUCC in the PPRB over the past 35 years. The results indicate the following: (1) Among the seven land uses, built-up land experienced the most dramatic change, followed by cropland, forestland, grassland, shrubland, waterbody, and bare land, with notable increases in built-up land and forestland, and rapid decreases in cropland, grassland, and shrubland. (2) The magnitude of land use changed very widely, with the highest change in the Pearl River Delta, followed by small coastal river basins in southern Guangdong and western Guangxi, the Dongjiang River Basin, the Hanjiang River Basin, the Xijiang River Basin, the Beijiang River Basin, and lastly, Hainan Island. (3) The largest increase happened in built-up land, with a total increase of 12,184 km², mainly due to the occupation of cropland and forestland, corresponding to the highest decrease in cropland, with a net loss of 10,435 km², which was primarily converted to forestland and built-up land. The study results are valuable in providing a scientific basis for policy overhaul regarding land resources and management to safeguard ecological balance and promote sustainable development in the Pan-Pearl River Basin. Full article

Research on land use carbon emission efficiency (LUCEE) in the Pan-Pearl River Delta (PPRD) can aid in formulating regional differentiated carbon reduction strategies. In this work, the inversion of carbon emissions using night-time light (NTL) data and the modified Carnegie Ames Stanford Approach (CASA) model were used to measure the net carbon emissions from land use (NCELU). On this basis, the SBM-undesirable model was used to assess the LUCEE. Additionally, the exploratory spatial data analysis (ESDA), Dagum Gini coefficient, and spatial convergence model were further introduced to analyze the spatial correlation, regional differences, and convergence trend of the LUCEE. Findings indicate that: (1) The NCELU showed an increasing fluctuation. During the period of 2006–2020, the NCELU increased from −168.58 million tons to −724.65 million tons. (2) The LUCEE exhibited a three-phase fluctuating downward trend of “decrease–rise–decrease”. The LUCEE first decreased from 0.612 in 2006 to 0.544 in 2008, then gradually increased to 0.632 in 2016, and finally decreased to 0.488 in 2020. Spatially, the LUCEE manifested a distribution characteristic of “high in the north and south, low in the middle”, with distinct spatial clustering features. (3) The overall Gini coefficient in the study period increased from 0.1819 to 0.2461. The primary contributor to the overall difference over the entire sample period was hypervariable density. (4) The PPRD and its various subregions displayed significant features of absolute and conditional β convergence. The speed of regional convergence from fastest to slowest was central > west > east, with the absolute convergence speeds of 0.0505, 0.0360, and 0.0212, respectively. Finally, policy recommendations are proposed to achieve regional carbon neutrality for the PPRD. Full article

Releasing the consumption potential of yachting tourism is important for marine economic development. The purpose of the study is to evaluate a comprehensive potential index for yachting tourism (based on consumption capacity, expenditure, quality, and environment) in 12 cities in China with high development potential for coastal yachting tourism. Data from 2014, 2017, and 2019 were included in the study. Analytic Hierarchy Process (AHP), entropy methods, and gray correlation analysis are applied in the study. A panel data regression model is used to estimate the factors affecting the consumption potential of yachting tourism. The results show that the consumption potential index of yachting tourism in China’s coastal cities has been continuously increasing, and the consumption potential is closely related to consumption quality and capacity. The consumption potential of yachting tourism is highest in Shanghai, Shenzhen, and Guangzhou. The overall spatial pattern shows a gradual decrease in consumption potential in the Pan-Pearl River Delta region to the Yangtze River Delta region and the Bohai rim region. Full article

With the continuous development of China’s marine economy and the increasing pollution in marine-related industries, how to implement a sustainable development strategy in the marine economy has become an important issue. Under the stochastic frontier analysis framework, this paper measures the technical efficiency of the marine economy in 11 coastal provinces in China under carbon emission constraints from 2006 to 2016 and analyzes regional differences and the dynamic evolution of technical efficiency and its influencing factors. Panel unit root test is applied to analyze the stochastic convergence of technical efficiency of the inter-regional marine economy. The result shows that: in the reference period, the technical efficiency of the marine economy is on the rise. Guangdong and Shanghai are in the lead. Technical level and industrial structure have a positive impact on technical efficiency, while the structure of property rights, FDI, energy prices, and energy structure have a negative effect on it. On the whole, the changes in the technical efficiency of coastal provinces present a process from concentration to differentiation. There is a stochastic convergence between the Pan-Pearl River Delta and the Yangtze River Delta. Raising the technological level, promoting low-carbon production in the marine industry, and strengthening inter-regional cooperation have a certain effect on the improvement of the technical efficiency of the marine economy. Full article

As a national regional development strategy and a vital region of the Belt and Road Initiative, the sustainable development of the Pan-Pearl River Delta (Pan-PRD) region is of great importance. The national development plan emphasizes improving total factor productivity (TFP) and promoting high-quality economic development. This paper uses the DEA-Malmquist index model to measure the TFP of nine provinces in the Pan-PRD region based on inter-provincial panel data from 2003 to 2020. Furthermore, it analyzes its growth trend and heterogeneity characteristics in the inter-provincial spatial, industrial, and city dimensions. The results show that in the time dimension, TFP shows a W-shaped fluctuation trend, technical efficiency grows slowly, and technical progress is the pillar of TFP improvement. The spatial dimension shows a high distribution in the center and low distribution in the south. On the industry dimension, the TFP is in descending order as follows: tertiary industry—secondary industry—primary industry. The spatial distribution is heterogeneous, exacerbating the uneven economic development within the region, and the regional industrial structure needs urgent optimization. The spatial development of city TFP is uneven, and the number of cities with a TFP below 1 is increasing. Finally, we suggest policies to accelerate regional collaborative innovation, cultivate advantageous industrial clusters, create an advantageous industrial ecosystem, and achieve sustainable development in the Pan-PRD region. Full article

Coastal reclamation in Guangdong Province is highly concentrated and is growing rapidly. However, intensive reclamation use has resulted in serious influence on the coastal ecosystem, directly and indirectly. The current conditions and spatial distribution of reclamations must be detected for coastal preservation and management using efficient technology. This study aims to find a suitable method and data to map reclamations accurately at a large scale. Pixel-based and object-oriented classification methods were applied in extracting the three typical types of coastal reclamation, namely, ports, aquaculture ponds, and salt pans, in Guangdong Province from Landsat 8 and Sentinel 2 images. The algorithms of a support vector machine, random forest, decision tree, and rule-based algorithm were performed. Classification results were compared with statistical measures to assess the performance of different algorithms. The results indicated that all of the algorithms could obtain classification results with high accuracy, whereas the object-oriented algorithm showed less efficiency than other algorithms in classifying ports with complicated features. High-resolution data were not always superior to lower-resolution data in the reclamation classification. Generally speaking, applying the rule-based object-oriented algorithm in Sentinel 2A MSI images is relatively efficient at detecting the reclamation use in coastal Guangdong considering its actual situation. The mapping of reclamations in the whole of coastal Guangdong shows that they present obvious agglomeration characteristics in the space. The aquaculture ponds are mainly distributed in the coastal zones of western Guangdong and eastern Guangdong, with the largest area of 77,963 ha. The other types of ports are mainly distributed in the coastal zones of the Pearl River Delta, with an area of 8146 ha, while salt pans are mainly distributed in the coastal zones of Jiangmen, Zhuhai, and Zhongshan, with a total area of 4072 ha. The results can provide key supporting data for decision making in coastal management and preservation. Full article

The inconsistent direction between environmental regulation and technological progress is receiving increasing attention, but scholars have neglected the relationship between the two in the open economy. Against this background and based on the panel data of 30 provinces in China from 2003 to 2015, we examined the effect of environmental regulation on the international research and development (R&D) spillover effect and its regional differences in three economic regions: The Bohai Rim, Pan-Yangtze River Delta, and Pan-Pearl River Delta economic regions. The results show that (1) at China’s macro level, and at that of the three economic regions, the level of environmental regulation and international R&D spillover from import trade or foreign direct investment channels show an inverted N relationship; that is, in all provinces the weak environmental regulation initially inhibited the international technology spillover. However, as the intensity of environmental regulation increased, the level of international R&D spillovers continually rose, but overly harsh environmental regulation was not conducive to the overflow of international technology; (2) the adoption of different environmental regulations will affect the international R&D spillover effect and the inverted N relationship of environmental regulation, thus changing the inflection point of environmental regulation; and (3) currently, the level of environmental regulation is relatively low, as most provinces have not yet broken through the first turning point of the inverted N, and only a few provinces are within the rising stage of the inverted N curve. This paper provides corresponding policy suggestions according to the above conclusions. Full article

Food supply from forests is a fundamental component of forest ecosystem services, but information relating to suitability for human consumption and sustainable utilization of non-timber forest products (NTFPs) in developing countries is lacking. To address this gap in knowledge, diverse datasets of edible plants and macro-fungi were obtained from field collections, historical publications, and community surveys across seven cities in Guangdong Province (GP), southern China. Seven edible parts and five food categories of plant species were classified according to usage and specific nutrient components. Edible plant species were also categorized into different seasons and life forms. Our results show that at least 100 plant species (with 64 plant species producing fruit) and 20 macro-fungi were commonly used as edible forest products in subtropical GP. There were 55 and 57 species providing edible parts in summer and autumn, respectively. Many edible plants had multiple uses. Tree and herbaceous species made up the majority of the total. Our study provides evidence that both edible plants and macro-fungi can enrich the food supply for residents in rural and urban areas by acting as supplemental resources. We therefore suggest that, in spite of the prevalence of imported foods due to modern infrastructure, edible NTFPs from subtropical forests might be leveraged to support the increasing demand for food in an era of rapid urbanization and global change. Full article

Peroxy acetyl nitrate (PAN) is an important photochemical product formed from the reactions between volatile organic compounds (VOCs) and nitrogen oxides (NO_x) under sunlight. In this study, a field measurement was conducted at a rural site (the backgarden site, or BGS) of the Pearl River Delta (PRD) region in 2006, with the 10 min maximum PAN mixing ratios of 3.9 ppbv observed. The factors influencing the abundance of PAN at the BGS site was evaluated by the process analysis through the Weather Research and Forecasting-Community Multiscale Air Quality (WRF-CMAQ) model. The results suggested that the increase of PAN abundance at the BGS site was mainly controlled by the gas-phase chemistry, followed by vertical transport, while its loss was modulated mainly by dry deposition and horizontal transport. As the dominant important role of gas-phase chemistry, to provide detailed information on the photochemical formation of PAN, a photochemical box model with near-explicit chemical mechanism (i.e., the master chemical mechanism, MCM) was used to explore the relationship of photochemical PAN formation with its precursors based on the measured data at the BGS site. It was found that PAN formation was VOC-limited at the BGS site, with the oxidation of acetaldehyde the most important pathway for photochemical PAN production, followed by the oxidation and photolysis of methylglyoxal (MGLY). Among all the primary VOC precursors, isoprene and xylenes were the main contributors to PAN formation. Overall, our study provides new insights into the PAN photochemical formation and its controlling factors, and highlighted the importance of gas chemistry on the PAN abundance in the PRD region. Full article

With the rapid economic growth and development, the problem of environmental pollution in China’s cities is becoming increasingly serious, and environmental pollution takes on a regional difference. There is, however, little comprehensive evaluation on the environmental performance and the regional difference of strictly-environmental-monitored cities in China. In this paper, the environmental performance of 109 strictly-environmental-monitored cities in China is evaluated in terms of natural performance, management performance, and scale performance by Data Envelopment Analysis (DEA), incorporating PM_2.5 and PM₁₀ as undesirable outputs. The empirical results show that: (1) At present, the natural performance is quite high, while the management performance is noticeably low for most cities. (2) The gap between the level of economic development and environmental protection among cities in China is large, and the scale efficiency of big cities is better than that of smaller cities. The efficiency value of large-scale cities such as Beijing, Shanghai, Guangzhou, Shenzhen, etc. is high, equaling 1; the value of smaller cities such as Sanmenxia, Baoding, Mudanjiang, and Pingdingshan is low, close to 0, indicating that big cities are characterized by high environmental efficiency. (3) From the perspective of region, the level of environmental performance in China is very uneven. For example, the environmental efficiency level of the Pan-Pearl River Delta region is superior to that of the Pan-Yangtze River region and the Bahia Rim region, whose values of environmental efficiency are 0.858, 0.658, and 0.622 respectively. The average efficiency of the Southern Coastal Economic Zone, Eastern Coastal Comprehensive Economic Zone, and the Comprehensive Economic Zone in the middle reaches of the Yangtze River is higher than that of other regions. Finally, corresponding countermeasures and suggestions are put forward. The method used in this paper is applicable to the performance evaluation of cities, and the results of the evaluation reflect the differences of the environmental performance level between strictly-environmental-monitored cities and different regions in China, providing reference for the balanced environmental development of cities and regions. Full article

Spatial-temporal hotspot pattern analysis of environmental pollution incidents provides an indispensable source of information for the further development of incident prevention measures. In this study, the spatial-temporal patterns of environmental pollution incidents in China in the period of 1995–2012 were analyzed, using the Spatial Getis-Ord statistic and an Improved Prediction Accuracy Index (IAPI). The results show that, in this period, the occurrence of environmental incidents exhibited a dynamic growth pattern but then dropped and continued to drop after the year 2006, which was considered a crucial turning point. Not coincidentally, this corresponds to the year when the State Council issued its National Environmental Emergency Plan, and following the examination of major incidents, special actions were taken to strengthen the control of incidents and emergency responses. The results from Getis-Ord General G statistical analysis show that the spatial agglomeration phenomenon was statistically significant after 1999 and that the level of spatial agglomeration was rising, while the Getis-Ord G_i^* statistical analysis reveals that environmental pollution incidents were mainly agglomerated in the Pan Yangtze River Delta and Pan Pearl River Delta regions. Accordingly, the spatial-temporal hotspot pattern based on the IAPI values at the provincial scale could be categorized into: stable hotspots, unstable hotspots, and cold-spot areas. The stable hotspots category was further divided into three subtypes: industrial distribution type, industrial transfer type, and extensive economic growth type. Finally, the corresponding measures for sustainable management were proposed: stable hotspots were classified as essential regions requiring the immediate prevention and control of environmental pollution incidents; unstable hotspots were characterized by their need for ongoing and continual prevention measures, and cold-spots were those areas that required strengthened environmental monitoring. Meanwhile, it was identified that a multi-level environmental pollution incident emergency response and regional (incident) joint control plan needed to be well prepared and carried out effectively. To prevent environmental pollution and the regional transfer of pollution from incidents, measures towards achieving regional environmental planning, environmental risk prevention, environmental emergency monitoring and adequate emergency responses must be efficiently implemented. Full article

In this paper, emergy analysis is used in association with the ternary diagrams and geographic information system (GIS) tools to improve the evaluation of sustainability for the Pan-Pearl River Delta (PPRD) region. Emergy accounting of PPRD is estimated, and various emergy-based indicators are reported. Ternary diagrams are drawn to provide a graphical representation of the emergy accounting data. Finally, the GIS tools are employed to assist in the emergy-based spatial analysis, and emergy density based on flat land area is mapped to reflect the intensity of emergy use in human activity areas. Results show the following: (1) the current development path of the PPRD region, with the value of emergy sustainability index (ESI = 0.227) significantly lower than one, is unsustainable in the long run; (2) Guangdong has the lowest ESI value (0.071), and the ESI values of Fujian, Guangxi, Hunan and Jiangxi are lower than 0.5, indicating that the economy in these provinces overly relies on non-renewable and imported resources; (3) Guizhou has a high emergy yield rate and is thus the main energy supplier in PPRD; and (4) among the nine provinces in PPRD, only Hainan has an ESI value (2.145) higher than one. Full article