Coastal Zone Of China Research Articles

Spatiotemporal Pattern Analysis and Prediction of Carbon Storage Based on Land Use and Cover Change: A Case Study of Jiangsu Coastal Cities in China

Accurate estimation of terrestrial ecosystem carbon storage and the scientific formulation of ecological conservation and land use policies are essential for promoting regional low-carbon sustainable development and achieving the goal of “carbon neutrality.” In this study, the FLUS–InVEST model was used to evaluate the carbon stocks of the Jiangsu coastal zone in China from 1995 to 2020 and scientifically forecast the changes in carbon stocks in 2030 under three scenarios: natural exploitation, ecological protection, and economic development. The results are as follows: (1) From 1995 to 2020, carbon storage in the coastal zone initially remained stable before declining, a trend closely linked to the accelerated urbanization and economic growth of Jiangsu Province. (2) By 2030, carbon storage under the three scenarios exhibits a pattern of “S1 decrease–S2 increase–S3 decrease,” with a more significant increase in construction land under the natural development and economic development scenarios compared to the ecological protection scenario. (3) The sensitivity of carbon storage to land use changes varies across scenarios. In the natural development scenario, carbon storage is most affected by forest reduction and construction land expansion. In the ecological protection scenario, it is more responsive to increases in non-construction land. In the economic development scenario, the expansion of construction land leads to the most significant decrease in carbon storage. Therefore, when formulating future territorial spatial planning policies and urban development strategies, it is essential to consider ecological protection and economic development scenarios comprehensively, taking into account carbon sequestration capabilities. This approach will ensure effective conservation and restoration of damaged ecosystems while safeguarding the robust development of urban economies and societies.

Effects of the comprehensive elimination of Spartina alterniflora along China's coast on blue carbon and scenario prediction after ecological restoration

Salt marshes cover the largest area among the three types of traditional blue carbon ecosystems in China's coastal zone, with the introduced smooth cordgrass (Spartina alterniflora Loisel.) being dominant in these marshes. The effects of eradicating S. alterniflora nationwide and the subsequent ecological restoration on blue carbon are unclear. This paper evaluates the variation in blue carbon during the national S. alterniflora eradication campaign, which involves mechanical tillage from 2022 to 2025, and proposes three scenarios for blue carbon changes after native vegetation is reestablished by 2050. The results show that, in 2025, plant carbon stock and soil carbon stock will decrease by 1.38 Tg C and 1.21 Tg C, respectively, in the areas where S. alterniflora has been removed and managed. Although blue carbon is reduced in coastal wetlands in 2025, carbon stock is expected to increase in restored native vegetated wetlands by 2050. S. alterniflora is resilient and competitive, posing a high risk in secondary invasion. Scenario Ⅰ suggests that S. alterniflora marshes could almost recover to their original state from 2022, with 7.70 Tg C stored in plant and soil carbon stocks. Scenario Ⅱ involves native vegetated wetlands coexisting with invasive S. alterniflora marshlands, with a total carbon stock estimated at 7.15 Tg C, reflecting a decrease of 0.39 Tg C in soil carbon stock and by 0.16 Tg C in plant carbon stock. In Scenario Ⅲ, mudflats dominant and native vegetated habitats are reestablished only in suitable sites, with the total carbon stock estimated at 5.63 Tg C, a 26.9% decrease compared to 2022 levels. While eradicating invasive S. alterniflora and restoring native vegetation in China's coast enhance the ecosystem services, it reduces blue carbon stocks. Therefore, developing additional strategies to increase carbon storage in coastal wetlands is necessary.

Sustainable urban planning to control flood exposure in the coastal zones of China

ContextSustainable development in coastal zones faces escalating flood risk in the context of climate change and urbanization, and the rapid urban growth in flood zones has been one of the key drivers. Therefore, understanding the Urban Exposure to Flooding (UEF) and its future scenarios is important in coastal zones.ObjectivesThe objectives of this study were: (1) to assess the future dynamics of UEFs in China's coastal zones, and (2) to identify a sustainable way of urban planning in controlling the growth of UEFs.MethodsFuture UEFs in coastal China were assessed during 2020–2050 by combining urban expansion model, scenario analysis, and flood exposure assessment. Alternative scenarios were considered of shared socioeconomic pathways (SSPs), representative concentration pathways (RCPs), strategies of urban planning.ResultsThe results show that the 1000-year flood UEFs along coastal China was expected to grow under SSP2-RCP4.5 from 9,879 km2 in 2020 to 13,424 (12,997–13,981) km2 in 2050, representing an increment of 35.88% (31.56%–41.52%). Alternatively, the strategy of sustainable development planning could reduce the newly added UEF by 16.98% (15.63%–18.67%) in a 1000-year flood scenario.ConclusionsThe findings proved that the ways of urban growth matters in terms of affecting food exposure and risk and flood risk should be incorporated into urban planning for a sustainable landscape. The study could offer methodology and support for sustainable development strategies in reducing future urban flood risk.

A theoretical method to characterize the resistance effects of nonflat terrain on wind fields in a parametric wind field model for tropical cyclones

Traditionally, an empirical speed-up factor was introduced to reflect the effects of nonflat terrain on near-surface wind speeds. In this paper, the resistance effects of nonflat terrain are considered by introducing the terrain drag coefficient in the parametric wind field model for tropical cyclones (TCs) with a theoretical method. Terrain effects on wind fields are investigated in complex areas along the coastal zone in China under TC conditions. The results show that the terrain drag coefficient is the function of the slope angle and is sensitive to the spatial resolution. After including the resistance effect of nonflat terrain, the TC intensities weaken overall during landfall, with a slight enhancement near the coastal zone. The wind speeds outside the radius of the maximum wind speed decrease, while the wind speeds within the radius of the maximum wind speed increase. Both the TC eye and the radius of maximum wind speed shrink, which is more obvious when the TC center is entirely over land. As a result, the location and magnitude of the maximum wind speed are affected by the nonflat terrain. The changed structure of the wind fields demonstrates the necessity of considering the effects of nonflat terrain in simulating the wind fields under TC conditions.

Emergy-Theory-Based Evaluation of Typhoon Disaster Risk in China’s Coastal Zone

The evaluation of typhoon disaster risk is a widely discussed global topic. Currently, the index system method has become a common approach for the evaluation of typhoon disaster risk. However, the indices within the system are calculated independently, and subjective human factors significantly influence the assignment of index weights. The existing studies lack purely quantitative assessment methods, which makes the studies less precise and more difficult for other researchers to replicate. To bridge this gap, this study employs emergy analysis methods based on thermodynamics to develop a typhoon disaster risk evaluation index system for China’s coastal zone. Without the interference of weights and other human factors, the system contains various quantitative indices, including aggregate impelling energy, typhoon intensity emergy, adaptability emergy, the vulnerability index, and the integrated typhoon hazard index. Subsequently, these indices and socio-economic data were spatialized, and the evaluation of typhoon disaster risk was conducted at the city grid level in the coastal zone of China. The findings reveal that the high-risk areas for typhoon disasters in China are concentrated in prefecture-level cities along the southeast coast. The typhoon disaster risk index is higher in the southern region compared to the northern region, with a decreasing trend in the distribution of the integrated typhoon hazard index from coastal to inland areas. The aim of this study is to use a new quantitative evaluation method (emergy) to evaluate typhoon disasters. It also serves as a theoretical foundation and technical support for national and local governments in the formulation of policies for disaster prevention and reduction.

Nighttime light in China's coastal zone: The type classification approach using SDGSAT-1 Glimmer Imager

Nighttime Light (NTL) is highly concentrated in China's coastal zone, leading to negative health impacts on both humans and wildlife. Particularly, in recent years, the widespread adoption of broad-spectrum Light-Emitting Diode (LED) light, a low-carbon technology providing substantial increases in luminosity, has led to certain ecological consequences. Thus, information regarding spatial distribution and composition of different NTL types is essential for formulating sustainable strategies that balance nighttime public security, energy consumption, and ecosystem conservation. However, the availability of such information remains limited. To address this challenge and meet the demand, we developed two new light indices, namely the Ratio Red Light Index (RRLI) and Ratio Blue Light Index (RBLI), based on SDGSAT-1 Glimmer Imager (GLI) multispectral NTL data. We then proposed a threshold method and applied it to the entire coastal zone of China to identify White LED (WLED), Red LED (RLED), and Other lights (Other). Results showed the following. (1) In the coastal zone of China, the total lighting area was 20,517 km2, including 20,257 km2 of terrestrial lights and 260 km2 of offshore lights; (2) WLED light covered 67% (13,727 km2) of all lighting areas, while RLED lights accounted for only 1% (220 km2); (3) Guangdong had the largest lighting area (5221 km2), with the proportion of WLEDs being the highest among all coastal provinces (almost 90%); (4) The proportions of lighting areas were relatively low in Guangxi, Liaoning, and Hebei. This study represents the first attempt to identify NTL types over large regions at a finer spatial resolution. The approach proposed, including the light indices of RRLI and RBLI, as well as the defined thresholds, is universal and robust for use in NTL type classification. The developed lighting type map, containing comprehensive information on the spatial distribution and composition of NTL, could facilitate the sustainable management of China's coastal zones.

Analysis of the Problems and Suggestions for Ecological Protection and Restoration of Coastal Zones in China

This paper analyzes the existing problems of ecological protection and restoration of coastal zones in China, and puts forward corresponding suggestions and solutions. In terms of technology, it is necessary to strengthen scientific and technological innovation and upgrading, develop repair technologies suitable for different coastal habitats, and strengthen the application of monitoring and evaluation technologies to ensure the effectiveness and sustainability of restoration work. In terms of management and policy, it is necessary to establish a comprehensive management mechanism, clarify the responsibilities and powers of various departments, and strengthen the formulation and implementation of laws and regulations. In addition, financial support should be enhanced, social participation should be encouraged, and international cooperation should be strengthened to jointly meet the challenges of ecological restoration. In terms of social economy, we should pay attention to sustainable development and achieve a win-win situation between economic growth and ecological protection by promoting the development of green industries and other ways. At the same time, it is also necessary to improve the public’s awareness and participation in coastal ecological restoration, strengthen environmental education and publicity work, cultivate the public’s awareness of the environment and responsibility for scientific and technological innovation, change economic factors and improve public education awareness, and achieve the effectiveness of coastal protection and restoration work to realize marine ecological safety and sustainable development.

Land use change in coastal zones of China from 1985 to 2020

Coastal regions stand as pivotal zones of interaction between the marine and terrestrial environments, holding substantial significance for both ecosystems and human societies. Since the 1980s, China’s coastal zones (CCZ) have undergone rapid economic expansion, a surge in urban development activities, and a considerable population increase, instigating significant alterations in land use along the coast. However, in recent years, studies regarding changes in land use along China’s coastal zones have been notably scarce. Utilizing the Comprehensive Lands Cover Database (CLCD) dataset, this study scrutinized the spatiotemporal patterns of land use along the Chinese coastline since 1985. It delved into the temporal and spatial variations in land use, ecological land transformations, and the spatiotemporal evolution of land use development intensity, examining these facets across provinces, municipalities, and different distance bands from the coastal zone. The research findings indicated: Overall, cropland and forest land predominantly occupied coastal zones, encompassing over 80% of the total area. Between 1985 and 2020, the primary changes involved a decrease in cropland and an increase in construction land, with a reduction of 5.97% in cropland, largely transitioning into construction land (84927.21 km2) and forest land (4218.55 km2), resulting in a 5.98% increase in construction land. Despite the intensification of land development, ecological land exhibited an initial rise followed by a declining trend. There existed distinct disparities in land use patterns among provinces and cities, with cropland and forest land prevailing in all areas except Macau. Construction land and land use development intensity witnessed significant increases, most notably in Macau and least pronouncedly in Guangxi. Variations in ecological land alterations were considerable, with Hebei and Guangdong witnessing increases while other regions tended towards stability or reduction. Each distance band manifests a unique land use pattern. Except for the 100-150 km zone, construction land demonstrates an increasing trend across all bands. Ecological land expanded initially but fluctuated further from the coastline. Land use development intensity decreased initially, then stabilized, with the 0-10 km zone showed the highest development intensity. Analyzing the spatiotemporal changes in land use along China’s coastal zones from 1985 to 2020 can offer valuable insights into the management and sustainable development of China’s coastal zones.

Spatio-temporal coupling analysis and tipping points detection of China's coastal integrated land-human activity-ocean system

The coastal zone is typically highly developed and its ocean environment is vastly exposed to the onshore activities. Land-based pollution, as the “metabolite” of terrestrial human activities, significantly impacts the ocean environment. Although numerous studies have investigated these effects, few have quantified the interactions among land-human activity-ocean across both spatial and temporal scales. In this study, we have developed a land-human activity-ocean systemic framework integrating the coupling coordination degree model and tipping point to quantify the spatiotemporal dynamic interaction mechanism among the land-based pollution, human activities, and ocean environment in China from 2001 to 2020. Our findings revealed that the overall coupling coordination degree of the China's coastal zone increased by 36.9 % over last two decades. Furthermore, the effect of human activities on China's coastal environment remained within acceptable thresholds, as no universal tipping points for coastal pollution or ocean environment has been found over the 20-year period. Notably, the lag time for algal blooms, the key indicator of ocean environment health, was found to be 0–3 years in response to the land economic development and 0–4 years in response to land-based pollution. Based on the differences in spatiotemporal interactions among land-human activity-ocean system, we employed cluster analysis to categorize China's coastal provinces into four types and to develop appropriate management measures. Quantifying the interaction mechanism within the land-human activity-ocean system could aid decision-makers in creating sustainable coastal development strategies. This enables efficient use of land and ocean resources, supports coastal conservation and restoration efforts, and fosters effective management recommendations to enhance coastal sustainability and resilience.

The amelioration and improvement effects of modified biochar derived from Spartina alterniflora on coastal wetland soil and Suaeda salsa growth

Exotic species Spartina alterniflora (S. alterniflora) are widely invaded in the coastal zones of China and threaten the native ecosystem functions. In this study, phosphorus-magnesium modified BC (P–Mg modified BC) included PA-Mg-BC and DAP-Mg-BC derived from S. alterniflora were successfully prepared by co-pyrolysis of biomass and diammonium phosphate (DAP) or phosphoric acid (PA) and magnesium oxide (MgO). The preparation process markedly improved the surface morphologies, P loading amount, and P-containing functional groups of modified BC. The characterization results indicated that stable and low-solubility Mg–P complex formed on the surface of PA-Mg-BC and DAP-Mg-BC, which delayed the rapid release of P. Moreover, the MgO improved the buffering capacity of PA-Mg-BC and DAP-Mg-BC to competitive anions (SO42− and CO32−) during P release. Meanwhile, pot experiment showed that the suitable applications of PA-Mg-BC and DAP-Mg-BC could improve soil quality and fertility by enhancing SOC, DOC, TN, TP and AP contents, as well as β-glucosidase activities. The amended soil pH and salinity compared to the original soil also declined through precipitation and acid-base neutralization. In addition, P–Mg modified BC could improve bacterial community structure and promote the growth and biomass of Suaeda salsa (S. salsa). This study could provide a feasible method for realizing ecological restoration of coastal wetland and resource utilization of S. alterniflora.

A Statistical Analysis of Energy Consumption Survey of Public Buildings in a Hot Summer and Cold Winter Coastal Zone of China

Public buildings consume the largest proportion of total energy consumption and carbon dioxide emissions in the building sector of China. Enhancing building energy efficiency becomes a necessary way to reduce greenhouse gas emissions and energy waste. In this study, 10-year real data from 2000 buildings covering five different types of public buildings in a hot summer and cold winter zone in eastern coastal China were investigated to analyze energy-saving potential (ESP) and the impacts of various influencing factors on building energy performance. The concept of energy consumption limit (ECL) was proposed and used for identifying high energy-consuming buildings and the calculation of ESP. Hotels, shopping malls, and office buildings were the top three types of buildings with high ESP. ESP for the high energy-consuming buildings based on the benchmark limits was more than 18%, and that for three-star hotels and shopping malls was 51%. In addition, a correlation analysis between energy consumption and influencing factors was carried out, which laid the foundation for the development of building energy performance assessment and diagnosis tools.

Study on the Influence of Salt Marsh Vegetation on Tidal Current and Sediment Transport in Intertidal Zone

Due to the sensitivity of the environment and immoderate human activities, the coastal zone in China is facing resource conflicts and environmental pressures. Salt marsh vegetation is regarded as an important measure for coastal ecological restoration. Therefore, it is of practical significance to study the influence of salt marsh vegetation on hydro-sediment dynamics. Based on the measured topography and tidal sediment data, a generalized model of salt marsh vegetation is established to study its effects on the dynamics of nearshore water and sediment. The results show that salt marsh vegetation has prominent effect of attenuating flow velocity and promoting sedimentation, and the ability differs depending on vegetation. Salt marsh vegetation can promote the development of tidal channels to shore, causing intensified erosion in the deep trough. The expansion of the vegetation area will allow the tidal channels to extend small branches to shore and connect with the vegetation front.

Spatial–Temporal Changes in Land Use and Their Driving Forces in the Circum-Bohai Coastal Zone of China from 2000 to 2020

Over the past two decades, the location and morphology of the coastline, as well as the land use/land cover (LULC) in the Circum-Bohai region in China, have undergone significant changes due to rapid industrialization and urbanization. Analyzing the temporal and spatial variation in coastal lines and LULC can provide a meaningful basis for the rational allocation of land resources. Using Landsat TM/OLI series dates from the Google Earth Engine (GEE) platform, this study applied the Linear Superposition Water Index (LSWI) and the Otsu threshold method (OTSU) algorithm to extract and analyze the coastline of the Circum-Bohai region. Additionally, the Random Forests (RF) method was employed to extract LULC information in the coastal zone. Using the geographical detector, we further explored the influence of social and economic factors, as well as natural factors, on spatial differentiation mechanisms of LULC change in the Circum-Bohai. Our results show that between 2000 and 2020, the Circum-Bohai coastline generally expanded towards the ocean by a total of 1062.99 km. The highest rate of change occurred during 2010 to 2015, and human activities were the primary cause of most of the changes, with the exception of the Yellow River Delta, where natural factors were dominant. The main types of LULC in the study area from 2000 to 2020 were farmland and construction land. The area of farmland proportion decreased by 1.75%, while the area of construction land proportion increased from 16.73% to 29.54%. Our findings indicate that the degree of land use in the Circum-Bohai is deepening. Based on our factor detection analysis, the added value of the secondary industry was the most critical influencing factor on LULC. Furthermore, the combined effect of the added value of the secondary industry and gross domestic product (GDP) has a significant driving impact on LULC. These findings can provide reference and data support for the sustainable development and comprehensive management of land resources. The relevant departments can use these results to prompt corresponding policies for the rational allocation of land resources.

Application of carbon emission prediction based on a combined neural algorithm in the control of coastal environmental pollution in China

The marine ecosystem provides the environment, resources, and services necessary for the development of every human society. In recent years, China's coastal zone has been polluted to varying degrees, which has seriously affected its development. The characteristics of marine environmental data include the variety of data types, the complexity of factors affecting the marine environment, and the unpredictability of marine pollution. Currently, there are few studies applying the clustering analysis algorithm to marine environmental monitoring. Then, carbon emissions (CEs) from coastal areas are predicted using marine environmental data. Therefore, this paper mainly studies the spatial and temporal accumulation characteristics of marine environmental data and uses the fuzzy c-means (FCM) algorithm to mine the data monitored by the marine environment. Meanwhile, it has been focused on the prediction of coastal CEs, and the grey model-back propagation (GM-BP) algorithm has been developed to predict CEs from coastal areas, which solves the problem that the traditional back propagation neural network (BPNN) cannot fully learn data features, which leads to a decline in accuracy. The experimental results showed that the FCM algorithm can divide the marine sample data into corresponding categories to distinguish polluted and unpolluted samples. The improved neural network model has a higher degree of non-linear fit and lower prediction error than a back propagation (BP) neural network. The main contribution of this paper is to first study the spatial and temporal accumulation characteristics of marine environmental data. The academic contribution of this study is to substitute the predictions of the three gray models (GMs) with the neural network structure simulation to finally obtain more accurate predictions. From a practical point of view, this study is helpful to a certain extent in alleviating the pressure of climate change due to increased CEs in global coastal zones. This study can also provide a new method of measuring environmental governance for marine environmental regulatory authorities.

Latitudinal variations of seed functional traits of Phragmites australis in Chinese coastal marsh

Functional traits of seeds reflect plant reproductive strategies adapting to environmental changes, which is an evolutionary behavior in natural selection and genetics. Study on seed functional traits is of great significance to deeply understand the long-term adaptive evolution of plants and seeds. We measured seed functional traits of a main indigenous species Phragmites australis, including seed size, seed weight, seed set, and seed production, in nine coastal marshes of the six provinces/cities along the coastal zone of China (21°29'-40°57' N), and analyzed latitudinal variations of functional traits. The results showed that seed functional traits of P. australis in Chinese coastal marshes varied significantly with latitude and that there were significant correlations among different traits. Seed size (including seed length, seed width, seed shape index, aspect ratio, and seed surface area), and 100-seed weight showed significant quadratic function relation with latitude, which firstly decreased and then increased with the increases of latitude, while seed setting rate firstly increased and then reduced. There was a trade-off between the number and size of P. australis seeds. Seed production per unit area significantly increased with latitude. Results of stepwise regression analysis showed that climatic factors were the main driver resulting in the difference of seed functional traits of P. australis between latitudes, followed by pH and salinity of soil porewater.

Projections of coastal flooding under different RCP scenarios over the 21st century: A case study of China's coastal zone

Among sea level rise (SLR)-induced threats to coastal regions, flooding inundation is considered the most serious, especially in China's coastal zone (CCZ). Previous attempts to simulate the inundation area caused by SLR at the macro spatial scale usually employed the bathtub model based on a large number of historical tide station data. However, these efforts mainly focused on simplifying the calculation of the inundation process at a large scale, but failed to improve the accuracy mainly due to the failure to exclude isolated depressions. Here, based on regional sea level data of the Integrated Climate Data Center (ICDC), the University of Hamburg, a physical ocean model (Finite Volume Coast and Ocean Model, FVCOM) was employed to simulate the maximum possible regional SLR in offshore China from 2021 to 2100 under the representative concentration pathways (RCPs) 2.6, 4.5, and 8.5 scenarios, respectively, and the hydraulic connectivity model was applied based on multi-source data to improve the simulation accuracy of the inundation area. Through these improved methods, the maximum possible inundation characters of CCZ over the 21st century were observed as follows: (1) Under RCP2.6/4.5/8.5 scenarios, the macro spatial patterns of inundation areas are similar, with the inundation area mainly distributing in the coastal areas around the Bo Hai, the coastal areas from Jiangsu to the estuary of the Yangtze River, the Pearl River Delta, and the western coastal areas of Taiwan, and the inundation area gradually expands and spreads over time. (2) Under the three scenarios, the maximum possible inundation area shows a wavelike rising trend, and by 2100, the inundation area is expected to exceed 48.89 × 103 km2 (RCP 2.6) and reach a maximum of 53.50 × 103 km2 (RCP 8.5). (3) There are significant differences in the inundation depth and flood frequency under the three scenarios, with the inundation characters of the high-emission scenario being the most extreme. Overall, our work can provide meaningful information for proper coastal urban planning, disaster prevention, and mitigation measures selection in China. The methodology can also be used for predicting the inundation areas in other coastal countries facing the threat of SLR.

Long-term human expansion and the environmental impacts on the coastal zone of China

Monitoring the long-term human expansions in coastal zones and evaluating their associated environmental impacts are critical to promoting a sustainable transformation of a society. This paper evaluated the long-term human expansion of reclamation, aquaculture ponds (saltern) and artificial surface in the Circum-Bohai Coastal Zone (CBCZ) of China based on the Google Earth Engine (GEE) platform and time-series land use (LU) function classification, and analyzed the impact of human expansion on the sustainability of coastal environment. Results show: (i) human activities in this coastal zone have expanded dramatically during the past 30 years, including an increase of 1555.50 km2 (+76.9%) for the reclamation area, 2065.53 km2 (+51.33%) for the aquaculture pond area, and 14329.99 km2 (+308%) for the artificial surface area; (ii) there are substantial spatial and temporal variations in human expansion in this coastal zone, mainly for Bohai Bay, Laizhou Bay, and Liaoning Bay, with the most intense expansion in the period 2003-2013, (iii) the spatial and temporal evolution of human activity expansion is strongly related to changes of water environmental quality and wetland loss, with the coupling degree of 70.73% and 79.41%, respectively. The expansion of human activity has led to a considerable loss of wetland number (from 2666.54 km2 to 1698.27 km2), indirectly affecting changes in offshore water quality. We found that human expansion is mostly driven by economic interests such as port construction, industrial parks, resource development, and tourism development, as well as a direct response to coastal zone development and protection policies.

How to Control Coastal Zone Through Spatial Planning? Taking the Construction of the Spatial Monitoring Index System of the Coastal Zone in China as an Example

Due to its fragile ecological environment and superior natural and location conditions, coastal areas are receiving extensive attention all over the world. Scientific space control is needed to ensure the harmonious development of the “human-land-ocean” system in this region. The monitoring index system is a crucial grasp of the national territory use control; it is also one of the main contents in the reform of China’s planning system in the new era. Therefore, based on the strategic idea of land–sea overall management and the concept of “life community of human, mountains, rivers, forests, farmlands, lakes, grasslands, and ocean”, this study puts forward three connotations of the index system of coastal spatial planning from the perspective of “function-structure-elements.” Then, adopting the methods of “multiple planning integration” and expert consultation and using the research idea of “setting control objectives, contents, and indicators,” an index system suitable for coastal space control is constructed. The results show that the index system puts forward 33 sub-indexes for coastal ecological space, living space, and production space and provides a basis for the high-quality development of coastal space through the restrictions and requirements on the total amount, bottom line, boundary, conversion, and quality of various spatial elements. This study can provide a basis for formulation, implementation, and later monitoring of coastal spatial planning and provide an index reference for the management of coastal areas in other countries in the world.

Spatiotemporal Dynamics of Bacterial Taxonomic and Functional Profiles in Estuarine Intertidal Soils of China Coastal Zone.

Bacteria play an important role in regulating carbon (C), nitrogen (N), and sulfur (S) in estuarine intertidal wetlands. To gain insights into the ecological and metabolic modes possessed by bacteria in estuarine intertidal wetlands, a total of 78 surface soil samples were collected from China's coastal intertidal wetlands to examine the spatial and seasonal variations of bacterial taxonomic composition, assembly processes, and ecological system functions through shotgun metagenomic and 16S rRNA gene sequencing. Obvious spatiotemporal dynamic patterns in the bacterial community structure were identified, with more pronounced seasonal rather than spatial variations. Dispersion limitation was observed to act as a critical factor affecting community assembly, explaining approximately half of the total variation in the bacterial community. Functional bacterial community structure exhibited a more significant latitudinal change than seasonal variability, highlighting that functional stability of the bacterial communities differed with their taxonomic variability. Identification of biogeochemically related links between C, N, and S cycles in the soils showed the adaptive routed metabolism of the bacterial communities and the strong interactions between coupled metabolic pathways. Our study broadens the insights into the taxonomic and functional profiles of bacteria in China's estuarine intertidal soils and helps us understand the effects exerted by environmental factors on the ecological health and microbial diversity of estuarine intertidal flats.

Isolation of Jannaschia sedimins sp. nov. from East Coast of China: Bacterial Taxonomy and Antimicrobial Resistance Analysis

A Gram-stain-negative, facultatively aerobic, pink and oval bacterium, designed OS4T, was isolated from a sediment sample taken from a coastal zone in China. The growth of OS4T occurred at 20–37 °C (optimal 25 °C), pH 7.0–8.5 (optimal pH 8.0), in 0–5.0% (w/v) NaCl (optimal 2.0%). According to the phylogenetic analysis, strain OS4T showed the highest sequence similarity (96.04%) with Jannaschia aquimarina GSW-M26T and shared 94.98% similarity with the type species of genus Jannaschia-strain J. helgolandensis 14858T. Chemotaxonomic analysis showed that the sole respiratory quinone was ubiquinone 10, and the major fatty acids (>5.0%) included C18:1 ω6c/ω7c, C18:0, and C10:0 3OH. The polar lipids consist of three phospholipids, two unknown amino-lipids, and four unknown glycerolipids. The DNA G + C content was 72.7 mol%. Based on the evidence presented in this study, strain OS4T represents a novel species of the genus Jannaschia, for which the name Jannaschia sedimins sp. nov. is proposed. The type strain is OS4T (=KCTC 82508T = MCCC 1K03755T). Both the phenotypic and the genetic analysis on the antimicrobial resistance genes indicate that OS4T is resistant to a wide range of classes of antibiotics, which highlights that the ocean could potentially serve as the natural reservoir of antimicrobial resistance genes.