Jiangsu Coastal Area Research Articles

Synergetic evolution mechanism of coastal resources utilization and coastline change of muddy coast in Jiangsu

Coastal areas possess unique geographical advantages and abundant resources, making them economic development hubs for coastal cities worldwide. However, the overexploitation of coastal resources significantly impedes the sustainable development of these areas. To address this issue, it is crucial to gain a comprehensive understanding of resource utilization patterns over time. Previous studies on resource utilization in the coastal areas of Jiangsu, China, have primarily relied on historical narratives with limited quantitative assessments. In this study, we utilize the Resource Utilization Comprehensive Index (RUCI) to evaluate the status of resource utilization in Jiangsu's coastal areas for the last 1300 years. Based on the characteristics of coastline changes from the Tang Dynasty to 1929 analyzed through the Digital Shoreline Analysis System (DSAS) in ArcGIS, we use entropy weight method (EWM), gray relation analysis (GRA) and Pearson correlation coefficient to determine the RUCI of coastal areas in Jiangsu and analyze its correlation with each evaluation index and influencing factor. The results show that (1) over the past 1300 years, the coastline of Jiangsu primarily underwent a sedimentation process characterized by three stages: slow sedimentation, rapid sedimentation, and north erosion followed by south sedimentation, (2) the comprehensive utilization of resources along the Jiangsu coast was gradually developed from the Tang Dynasty to the Republic of China, with the best utilization achieved during the Qing Dynasty, and (3) the changes in the coastline exhibited a substantial influence on the comprehensive utilization of resources and there was a high correlation between the two. Based on these findings, we propose several policy development suggestions. This study provides a scientific basis for understanding the synergetic evolution mechanism of coastal resources utilization and coastline change in Jiangsu under global change.

Morphological characteristics and genetic diversity of floating and attached Ulva prolifera––A case study in the Yellow Sea, China

Green tides in the Yellow Sea have occurred periodically since 2007, impacting the ecological environment and green algal communities along the coasts of Jiangsu and Shandong provinces in China. To investigate the morphological characteristics and genetic diversity of Ulva prolifera, we conducted surveys and comparative analyses of both its floating and attached forms along the coastal areas of Jiangsu and Shandong. The results revealed that the external morphology of the floating U. prolifera was multibranched. The attached U. prolifera displayed significant morphological variation among individuals. Based on the analysis of the amplified characteristic bands of the chloroplast gene, it was shown that both floating and attached U. prolifera could hybridize with Ulva linza. The genetic diversity of U. prolifera was studied using mitochondrial and chloroplast genome fragments. All floating U. prolifera and three strains of attached U. prolifera belonged to the same haplotype. The genetic diversity of floating U. prolifera was low, and there were some genetic differences with attached U. prolifera. The attached U. prolifera displayed a higher level of genetic diversity with abundant sites of variation and haplotypes.

Distribution Characteristics of Rainfall Erosivity in Jiangsu Coastal Areas

The issue of regional soil and water loss caused by human activity is particularly severe in coastal regions. Since coastal reclamation areas are a valuable land reserve resource, it is of practical significance to understand the distribution characteristics of rainfall erosion and its impact on soil erosion for the prediction, evaluation, and management of regional soil and water resources. Rainfall erosivity should be updated and estimated from simplified indices. This paper analyzed the observed rainfall data of field runoff plots in Dongtai City, Jiangsu Province, between 2011 and 2017. According to the standard of erosive rainfall in coastal areas, reporting 10.8 mm of rainfall or 7.6 mm·h−1 of I30 (maximum 30 min rainfall intensity), the annual average erosive rainfall frequency in Dongtai City was 37.7 and the annual erosive rainfall was 1082.0 mm on average, which accounted for 51.6% and 90.6% of the total rainfall frequency and the total rainfall, respectively. Moreover, the annual average rainfall erosivity in the region from 2011 to 2017 was 7717.4 MJ·mm·hm−2·h−1. The annual distribution of rainfall erosivity was irregular, with an average monthly erosivity value of 4501.8 MJ·mm·hm−2·h−1. Since the accumulated rainfall erosivity of Dongtai City in the flood season (May to September) accounted for 88.1% of the total rainfall erosivity, it is essential to focus on preventing soil and water loss in the flood season. This paper established a rainfall-based model and a composite model and intensity appropriate for a single event and monthly rainfall erosivity in the region. Both models can be used to calculate the annual rainfall erosivity, but only the composite model based on rainfall amount and intensity is recommended for calculating single and monthly rainfall erosivity levels in Jiangsu coastal areas. The empirical formulas in Jiangsu coastal areas can be updated using more recent rainfall data and assess soil erosion risk accurately.

Microplastic pollution in the offshore sea, rivers and wastewater treatment plants in Jiangsu coastal area in China

Offshore areas are particularly important in recognizing microplastics pollution because they are sinks of land imports and sources of ocean microplastics. This study investigated the pollution and distribution of microplastics in the offshore Sea, rivers and wastewater treatment plants (WWTPs) in Jiangsu coastal area in China. Results showed that microplastics were widely present in the offshore area, with an average abundance of 3.1–3.5 items/m3. Significantly higher abundance was present in rivers (3.7–5.9 item/m3), municipal WWTPs (13.7 ± 0.5 item/m3), and industrial WWTPs (19.7 ± 1.2 item/m3). The proportion of small-sized microplastics (1–3 mm) increased from WWTPs (53%) to rivers (64%) and the offshore area (53%). Polyamide (PA), polyethylene (PE), polyvinyl chloride (PVC), polypropylene (PP), polystyrene (PS), and rayon (RA) were dominant types of microplastics. Both living and industrial sources contributed to the prevalent microplastics in the offshore Sea. Redundancy analysis showed that small-sized microplastics (1–3 mm) were positively correlated to total phosphorus (TP), while large-sized microplastics (3–5 mm) were positively correlated to TP and NH3–N. The abundance of PE, PP and PVC microplastics were positively correlated to TP and total nitrogen (TN), thus nutrients could be indicators of microplastics pollution in the offshore area.

Effects of tidal flat reclamation on the stability of coastal wetland ecosystem services: A case study in Jiangsu Coast, China

Tidal flats have great potential to expand human living space and provide abundant resources. However, large-scale reclamation and development activities have had profound impacts on regional ecosystems, and it is important to grasp the comprehensive characteristics of the effects from a macro perspective. We selected the coastal area Jiangsu, China, as a typical area, and investigated the impact of reclamation on the coastal wetland system from the perspective of ecosystem services stability. The optimal equilibrium state was used as a benchmark and a stability deviation index (SDI) of ecosystem services was constructed by clarifying the connotation of stability. The stable state and evolution characteristics of ecosystems in different areas (coastal administrative areas, tidal flat areas, and Yancheng National Nature Reserve (YNNR)) were screened and evaluated. Based on the SDI, an overall ecological impact assessment system was developed, and the impact of tidal flat reclamation on ecological stability and its cumulative effects were quantified. The results showed that in the past 40 years, the overall ecological stability of Jiangsu coastal area was “Basically Stable (II)”, while that of the YNNR was “Weakly Stable (III)”. The impact of reclamation on the ecosystem stability of the coastal tidal flat area was significant, with a contribution rate of 73.5 %, and the threshold of stability transition in this area was reached when the reclamation amount was 1251.33 km2. The extent to which reclamation explained the stability variation in the core zone, buffer zone, and experimental zone of YNNR gradually decreased, indicating that the impact of reclamation was greater when strong protection measures were in place. The southern region will reach the maximum threshold of the cumulative effect of instability in 2072. This study provides ideas for the analysis of the comprehensive impact of reclamation on coastal wetland ecosystems, and can provide guidance for the efficient utilization and protection of tidal flats.

Spatial Differentiation and Driving Mechanism of Agricultural Multifunctions in Economically Developed Areas: A Case Study of Jiangsu Province, China

Revealing the spatial patterns of differentiation and the driving mechanism of agricultural multifunctional patterns is an important aspect of coordinating the functional optimisation and coordinated development of different agricultural regions. On the basis of understanding the connotation of agricultural multiple functions, this paper constructed an evaluation index system of agricultural multiple functions. Taking Jiangsu Province as a typical case, the spatial patterns of agricultural multifunctions in Jiangsu since 1978 were analysed by using the entropy weight TOPSIS (technique for order preference by similarity to ideal solution) method and ESDA (exploratory spatial data analysis) model, and the influencing mechanism of agricultural multifunction spatial differentiation was revealed by a geographic detector model. The results showed that (1) the cities with higher agricultural grain production functions were mainly concentrated in Yancheng and Huai’an; cities with higher agricultural economic development functions were mainly distributed in the coastal areas of Jiangsu; cities with higher agricultural social security functions were mainly concentrated in the Suzhou–Wuxi–Changzhou metropolitan area; and cities with higher agricultural ecotourism functions evolved from Nanjing–Zhenjiang to Suzhou–Wuxi–Changzhou. (2) The H–H (high–high) cluster pattern of the agricultural grain production function shifted from southern Jiangsu to northern Jiangsu. The H–H clusters of the agricultural economic development function and social security function were mainly distributed in Suzhou–Wuxi–Changzhou, while the L–L (low–low) cluster was mainly distributed in northern Jiangsu. The H–H cluster of agricultural ecotourism functions was mainly distributed in the areas with rich mountain and hill resources or dense water networks in Jiangsu. (3) The agricultural multifunction pattern differentiation was affected by the natural environment and economic and social comprehensive factors; the level of economic development and population employment structure were the leading factors of agricultural multifunction spatial differentiation; industry structure and people’s living conditions were the important driving forces of agricultural multifunction spatial differentiation; and the natural environment and population density were the basic factors underlying agricultural multifunction spatial differentiation.

Effects of green tide on microbial communities in waters of the Jiangsu coastal area, China.

Recently, green tide outbreaks have resulted in severe coastal ecology and economic effects in China. Jiangsu coastal areas are usually the site of early green tide outbreaks. To clarify the effects of green tide outbreaks in Jiangsu coastal areas, this study analyzed microbial communities during green tide-free and green tide outbreak periods (May and July, respectively) through 16S rDNA sequencing. Sequences were clustered into 4117 operational taxonomic units (OTUs), 1044 and 3834 of which were obtained from the May and July groups, respectively. Redundancy analysis indicated that green tide occurrence was closely associated with the temperature, pH, and concentrations of various nutrients. Diversity analysis revealed that the July group had a richer microbial community than the May group, in agreement with the results of propagule culture. Moreover, comparative analysis revealed that samples in the May and July groups clustered together. According to Megan analysis, the May group had much more Psychrobacter, Sulfitobacter, and Marinomonas than the July group, whereas the other genera were predominantly found in July, such as Ascidiacerhabitans, Synechococcus Hydrotalea, and Burkholderia-Paraburkholderia. These findings suggest that green tide outbreaks affect marine microbial communities, and detecting the changes in the identified genera during green tide outbreaks may contribute to green tide forecasting. PRACTITIONER POINTS: Jiangsu coastal areas are usually the site of early green tide outbreaks. Green tide occurrence was related to the concentrations of various nutrients. Microbial species and community structure significantly changed after green tide outbreak.

Enhancing salt leaching efficiency of saline-sodic coastal soil by rice straw and gypsum amendments in Jiangsu coastal area

High salinity-sodicity affects large areas of newly-reclaimed land in many coastal regions that need proper leaching before they become productive. However, poor soil properties make salt-leaching process ineffective. In this study, leaching experiments were used to assess the effectiveness of adding gypsum and rice straw in improving salt-leaching efficiency. Four treatments, control, rice-straw, gypsum, and gypsum and rice-straw, with two replicates, each were tested to find the optimal combination. After soils were leached, property changes were measured, such as main dissolved cations, conductivity, and pH. Gypsum and rice straw treatment turned out to be the best, where EC e , sodium adsorption ratio, and exchangeable sodium percentage dropped to 3.61%, 5.04%, and 8.14%, respectively. These values reached the safe limit of salinity-sodicity (EC e ≤ 4dS m −1 , ESP ≤ 15%). In addition, the incorporation of rice-straw with gypsum affects the ability to increase the removal of sodium and thus enhance salt-leaching efficiency.

The Effects of Tidal Flat Reclamation on the Stability of the Coastal Area in the Jiangsu Province, China, from the Perspective of Landscape Structure

As one of the most important wetland systems, coastal wetlands play an important role in conserving water, regulating the climate and protecting biodiversity. However, due to large-scale and long-term tidal flat reclamations, the landscape structure and function of the coastal wetlands have been greatly affected. Therefore, it is necessary to understand the spatio-temporal characteristics of the impact of tidal flat reclamation on regional ecology and to quantitatively assess the relationships between them. In this study based on long-term, multiperiod remote sensing data, the main spatio-temporal variation characteristics of stability, and the relationship between stability and tidal flat reclamation were analyzed with regard to the influence scope of tidal flat reclamation. The results showed that a substantial decrease in natural wetlands in 1980, mainly caused by tidal flat reclamation, was discovered in the Jiangsu coastal area, and the influence scope of tidal flat reclamation on regional landscape ecology was roughly 30 km. In the affected area, the overall stability had a tendency to improve, but the stability change characteristics between reclamation area and non-reclamation area varied greatly. Especially in the reclamation area, the stability of construction wetlands and non-wetlands deteriorated. Spatially, the stability outside the reclamation area had the characteristics of first deteriorating and then improving as the distance from the reclamation area increased. Under the influence of tidal flat reclamation, the influence of different use types of TFR on stability was not completely consistent, and the influence of the same uses type of tidal flat reclamation on different landscapes was also different.

Long-term evolution analysis of coastal geomorphology in Jiangsu based on Google Earth Engine

In the past few decades, the tidal flats along the Jiangsu coast have been extensively modified, which has affected the function of a tidal flat ecosystem. In this paper, 4556 Landsat remote sensing images were processed based on the Google Earth Engine to classify features in the region from 1989 to 2019, and the overall and local geomorphology of the Jiangsu coastal area in the past three decades were analyzed and discussed. The trend of tidal flats in the study area has decreased 345.61 km2, with an average loss of 11.52 km2 per year. The expansion of human activities has led to the migration of the Jiangsu coast to the sea, the reduction of natural coastline fragmentation, and the expansion of artificial coastline to the sea.

Spatial variation and optimization of ecological carrying capacity in Jiangsu coastal area, China

The research on spatial pattern and optimization of regional ecological carrying capacity is especially necessary to promote the overall development of economic transformation, upgrading and ecological protection and restoration. This study chose the natural, social and economic complex ecosystem of Jiangsu coastal area as subject. The concept model of pressure-state-potential (PSP) of ecological carrying capacity was established. A total of 15 indices were used to represent the interaction of three level states. With the support of GIS and other space technologies, the magnitude, spatial variation of regional ecological carrying capacity were examined through comprehensive evaluation of multiple indices and analysis of single index. Results showed that the spatial pattern of the suitability of single factor ecological carrying capacity in Jiangsu coastal area showed a variety of trends. There were significant differences in the area, proportion and layout of the same index across different cities and counties. The spatial differentiation of pressure and state superposition index showed that low pressure suitable bearing, low pressure generally suitable bearing, low pressure unsuitable bearing, high pressure suitable bearing, high pressure generally suitable bearing, bearing high pressure unsuitable bearing area was 3971.42, 6885.21, 3705.23, 4597.03, 6853.26, and 6403.97 km2, accounting for 12.3%, 21.2%, 11.4%, 14.2%, 21.1% and 19.8% of the total area, respectively. The results of spatial differentiation of superposition index of state and potential showed that the area integral of low potential suitable bearing, low potential general sui-table bearing, low potential unsuitable bearing, high potential suitable bearing, high potential general sui-table bearing and high potential unsuitable bearing was 3030.79, 6545.30, 5874.31, 3253.31, 7614.38, and 6097.83 km2, accounting for 9.4%, 20.2%, 18.1%, 10.0%, 23.5% and 18.8% of the total area, respectively. Most areas showed distribution characteristics of low pressure bearing area corresponding to high potential bearing area and high pressure bearing area corresponding to low potential bearing area in spatial pattern. There was an interaction of mutual influence, mutual promotion and collaborative promotion between pressure and state superposition index and state and potential superposition index.

Source apportionment of polycyclic aromatic hydrocarbons and black carbon at the western coastal areas of the Yellow Sea based on isotopic signatures

The stable and radioactive isotopes (δ13C, Δ14C and δ2H) of black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) in the sediment from the western coastal areas of the Yellow Sea (i.e. the Jiangsu coastal areas (JCA)) were examined to identify the sources these environmental pollutants in the JCA. The results presented that the spatial heterogeneous characteristics of BC and PAHs were markedly presented in the JCA. This was suggestive of presence of the contributions of multiple potential environmental pollution sources. This can be solved and decoupled by applying the Bayesian mode. Accordingly, the statistical model showed that the major environmental pollution contributions is considered as coal combustion (39%) in the JCA. The liquid fossil fuels, petrogenic sources, and biomass combustion were accounted for 27%, 19%, and 15% in the JCA, respectively. The stable and radioactive carbon isotopic ratios (δ13C and Δ14C) of BC collected from the JCA are also applied to discriminate quantitatively the source of contamination. It is demonstrated that the BC in this study originates mainly from combustion of fossil fuels. And rock-derived BC as well as C3 and C4 plants combustions are also numerically predominant for BC and PAHs pollution in the coastal area. It is implied that the environmental PAHs and BC in the JCA seem to origin relatively homologies sources. Furthermore, it is suggested that the stable and radioactive carbon isotopes as well as hydrogen isotopes may be powerful and useful method to source apportionment, and have much advantages to clarify quantitatively BC and PAH pollutions in the coastal environment, but also detailed insights into the source apportionment and fate of the organic carbon in the marginal sea.

Resistance to Registered Herbicides: Gramineae Weeds in Wheat Field in the Coastal Areas of Jiangsu

Resistance to Registered Herbicides: Gramineae Weeds in Wheat Field in the Coastal Areas of Jiangsu

Microplastic pollution and quantitative source apportionment in the Jiangsu coastal area, China

We investigated the pollution characteristics, the spatial distributions of microplastics, and the source compositions in the Jiangsu Coastal Area, China. The average abundance of microplastics in the surface water and sediment were 0.0998 ± 0.0720 items/m3 (using a trawl with 333-μm mesh)and 0.1858 ± 0.0927items/g, respectively. The concentration of microplastics showed a distribution trend of high near shore and low far shore in the east-west direction, and were the highest in the southernmost part. According to microplastics found in the surface water, the results of a quantitative source apportionment indicate that the most common source in the northernmost and southernmost regions were clothing fibers, accounting for 38.40% and 40.44% of the total source, respectively. While the major source type in the middle region was the decomposition of hard, large plastic waste. Finally, we suggested some control measures for the main types of microplastics observed in the different regions.

Temporal and spatial distribution characteristics and causes of sea fog in Jiangsu coastal area

Based on the observation data of Binhai and Lvsi stations in the past ten years, this paper analyzes the temporal and spatial distribution characteristics and formation conditions of sea fog along the coast of Jiangsu Province, and obtains some rules, such as: winter and spring are the seasons of frequent sea fog along the coast of Jiangsu Province, when the relative humidity is≥85%, the temperature difference between water and air is within plus or minus 8°C, when the southeast wind is easier to form fog, and the wind speed generally does not exceed 5 levels. In addition, the sea fog in Jiangsu coastal area can be generally divided into inverted trough type, low pressure type, cold air type and high pressure type, and it is easy to form fog when inverted trough. Continuous multi-day sea fog is often the continuous influence of various weather situations. All these provide ideas for the prediction of sea fog in Jiangsu coastal area.

Estimation of regional groundwater resources carrying capacity in Yangtze River Economic Belt

It is of great significance to evaluate the groundwater resources carrying capacity, for understanding the basic situation of regional groundwater resource availability and utilization, establishing a monitoring and warning mechanism for resources and environment carrying capacity, and supporting the research oriented to national spatial planning. In this paper, groundwater resources carrying capacity is proposed based on analysis of the quantity, quality and ecological feature of groundwater in Yangtze River Economic Belt, an evaluation methodology is established respectively from background and status of carrying capacity. Results show that integrated carrying capacity is medium in this region. The number of cities with strong, medium-strong, medium, medium-weak, and weak integrated carrying capacity are 27, 28, 51, 15, and 8 respectively. Cities with strong and medium-strong integrated carrying capacity are mainly located in Middle-Lower of Yangtze River, Huang-Huai-Hai Plain and Sichuan Basin. Cities with medium-weak and weak integrated carrying capacity are mainly located in coastal areas of Jiangsu and Zhejiang provinces, Sichuan red layer area, north of Sichuan Plateau, and Jinsha River basin.

A DSAS-based study of central shoreline change in Jiangsu over 45 years

A large-scale sand ridge group is distributed in the central Jiangsu coastal area, and a deposition muddy sea bank was developed in the nearshore area. Quantitative monitoring of coastline changes is of great significance for tidal beach development and protection. The shorelines of the central coast of Jiangsu within six periods (1973–2018) were extracted in this study, and their length changes over the years were analyzed. The Digital Shoreline Analysis System (DSAS) was employed to generate a cross section perpendicular to the baseline and calculate the linear regression rate (LRR) of the shoreline, changes in end point rate (EPR), and net shoreline movement (NSM), based on which the shoreline change features were analyzed. The DSAS results indicated that the shorelines in the study area maintained fluctuating growth and presented a continuous advancing trend towards the sea. From the changes in shoreline evolution distance during 1973–2018, the advancing shorelines in the study area accounted for over 50% of the total shorelines and presented first rising and then declining trends with the period of 2003–2013 taken as the time boundary. The average shoreline change rate was 207 m/year, and the periods with the highest change degrees were 1983–1993 and 1993–2013. The shoreline change tended to be stable during 2013–2018, and only a few estuaries and ports underwent obvious erosion and sedimentation.

江苏沿海滩涂围垦与社会经济发展的耦合关系

沿海滩涂湿地是脆弱的生态敏感区，滩涂围垦是沿海国家和地区拓展土地资源的重要方式之一。近年，沿海地区快速城市化下的滩涂围垦导致了沿海湿地生态系统退化等一系列环境问题。基于环境库兹涅茨曲线（Environmental Kuznets Curve，EKC）模型，以江苏北部沿海湿地为研究区，结合遥感影像和社会经济数据，刻画滩涂围垦过程、强度及社会经济发展过程，揭示近40年江苏沿海滩涂围垦主要类型、阶段性变化特征，阐述滩涂围垦与社会经济发展的耦合关系。研究结果显示，养殖水体扩张是近40年江苏滩涂围垦利用的主要方式；相比养殖水体聚集发展的盐城市，以启东为典型代表的南通市经历了相对较完整的养殖水体的滩涂围垦过程，其养殖水体面积与区域渔业产值存在指数关系，即当人均地区产值达到约9.55万元时，区域渔业产值的增长不再以通过围垦增加养殖水体面积为主要途径；从江苏沿海滩涂围垦来看，滩涂围垦与社会经济发展之间存在典型倒U型曲线关系。苏北滩涂围垦可分为3个阶段，初期阶段（1980-2005年），滩涂围垦随着经济发展而急剧增加；中期（2005-2014年），当人均GDP约为3.64×10⁴元时滩涂围垦速度达最大；后期（2014-2018年），滩涂围垦随着经济发展呈现下降趋势。3个阶段中，单位滩涂围垦面积与人均GDP增长关系由4.11元/km²，17.08元/km²增加至60.77元/km²，呈显著增加的趋势。经济发展，农业和农村经济改革以及国家和地方各级政策均对滩涂围垦具有重要影响。严格的国家环境保护政策将是有效控制滩涂围垦、保护生态环境的重要手段。;Tidal flat wetland is one of the most sensitive and fragile ecosystems in the world, and tidal flat reclamation plays an essential role for coastal countries or regions to expand land. In recent years, with rapid urbanization, tidal flat reclamation in coastal areas has led to a series of environmental problems such as wetland ecosystem degradation. Taking coastal wetlands in northern Jiangsu as a research area, based on the Environmental Kuznets Curve (EKC) model, this study attempted to characterize the process of tidal flat reclamation and socio-economic development, and reveal the phase of reclamation over the past 40 years, and explain the coupling relationship between tidal flat reclamation and social economic development. The results showed that the expansion of aquaculture water has been the main characteristics of reclamation in Jiangsu tidal flats in the past 40 years. Compared with Yancheng City, where aquaculture water bodies are clustered developing, Nantong City, which is represented by Qidong, has experienced a relatively complete tidal flat reclamation process for aquaculture water bodies. An exponential relationship was observed between the area of aquaculture water bodies and the regional fishery output value in Qidong, that is, when the per capita regional output value reached approximately 95,500 Yuan, the increase of regional fishery output value no longer depended on increasing the aquaculture water area through reclamation. There was a typical inverted U curve relationship between tidal flat reclamation and economic development in north Jiangsu coastal area in the past 40 years. The process of reclamation in north Jiangsu coastal area can be divided into three phases. In the early phase (1980-2005), the reclamation increased sharply with economic growth. In the middle phase (2005-2014), the increasing trends of reclamation and economic growth continued, with a turning point appeared, when the per capita GDP was about 3.64×10⁴ Yuan, and the maximum reclamation appeared with the speed up to 146.34 km²/a. In the late phase (2014-2018), tidal flat reclamation showed a downward trend while the economy still increasing. In the three stages, the relationship between reclamation and per capita GDP growth increased from 4.11 Yuan/km² and 17.08 Yuan/km² to 60.77 Yuan/km², showing a significant growing trend. Economic development, agricultural and rural economic reforms, and national and local policies make important impacts on tidal flat reclamation. The strictly national environmental protection policies would be of great significance to effectively control tidal flat reclamation and protect the coastal ecological environment.

Species richness patterns of waterbirds overwintering on the Jiangsu coast for coastal reclamation

It is vital to identify factors that affect the overwintering of waterbirds for conservation purposes. In this study, during the winter of 2018–2019, we documented 177,414 individuals of 74 species of waterbirds in the Jiangsu coastal area, an important but poorly known overwintering location. Of the species observed, 12 were listed as threatened. We found that natural wetlands loss is a significant contributor to population declines among overwintering waterbird species in the Jiangsu coastal area, greater than anthropogenic disturbance. This loss has forced waterbirds to choose artificial wetlands, where a total of 47 species were detected. Sorted by key zones for overwintering waterbirds, 16 surveying zones were identified in the area, and most are not fully protected. Thus, conservation efforts aimed at waterbirds should focus on at least 12 conservation gaps in diversity hotspots, emphasizing the management of artificial wetlands in the Jiangsu coastal area.

Analysis of the Coupling Mechanism Between Economic System and Water Resource System in Jiangsu Coastal Area

Chen, H. and Chen, M., 2020. Analysis of the coupling mechanism between economic system and water resource system in Jiangsu coastal area. In: Wan, Z. (ed.), Coordinated Sustainable Development in Coastal Areas: Environment and Economy. Journal of Coastal Research, Special Issue No. 109, pp. 223–227. Coconut Creek (Florida), ISSN 0749-0208.The research on the coupling relationship between economic systems and water resources systems has always been a hot topic in the academic field. Due to the characteristics of its own economy and water resources environment, it is particularly necessary to study the coupling mechanism between the economic system and the water resources system in coastal areas. Based on the coupling system perspective, this paper constructs the coupling mechanism model of the economic system and the water resources system. On this basis, the author obtains the following conclusions through the research on Jiangsu coastal areas: (1) There is a complex coupling mechanism between the economic system and the water resources system. When the operation of the two systems conflicts, the water resources system will send a response signal to the economic system. (2) The coupling state between the economic system and the water resource system in Jiangsu coastal area showed a better coordinated situation from 2000 to 2011. From 2012 to 2014, the coupling between the economic system and the water resources system weakened and was in a state of basic coordination. Therefore, the industrial structure of this region needs to be adjusted and the resource-friendly economic model needs to be established.