Climate change and China's coastal zones and seas:Impacts,risks,and adaptation

This article provides an assessment of the changes in marine climate drivers(hazards),associated impacts,risks,and adaptation to the coastal China zones and seas since the mid 20th century.The results show that:①Marine climate drivers,such as ocean warming,sea level rise,typhoon,storm surges and marine heat waves(MHWs),have increased significantly in strength,frequency and range over the past decades.②Ocean warming has caused substantial changes in marine phenology,species composition,geographical distribution,and frequent occurrences of ecological disasters such as red tides,green tides,and macro-jellyfish outbreaks,while MHWs have induced degradation in tropical coral reefs and major losses in the marine aquaculture industry in the coastal China seas.③Sea level rise threatens the typical habitats of coastal wetlands such as mangrove and estuaries,and exacerbates coastal erosion,seawater intrusion and the impacts of typhoon,storm surges on the coastal flood disasters.④Human activities,such as large-scale reclamation,pollutant discharge,and overfishing,have increased the exposure and vulnerability of China's marine and coastal ecosystems,leading to the low-aging and miniaturization of fishery types,decline of offshore fishery resources,reduction of coastal wetland areas,and degradation of biodiversity and ecosystem stability.⑤Under different climate scenarios such as low and high greenhouse gases emission scenario(RCP 2.6 and 8.5),as the warming and sea level rise in the coastal China seas continue,extreme sea level(ESL)events will occur more frequently,e.g.,by the end of this century,the current once per century ESL events will become annually or even annually less(RCP 8.5)in many coastal areas,such as at Lvsi and Xiamen tidal gauge stations;and the ESL events could pose serious risks on the coastal areas.Finally,the article further discusses the adaptation measures and related uncertain issues to address climate change in the coastal China zones and seas,and puts forward relevant countermeasures and suggestions in order to reduce its negative impacts on the sustainable development of human community.

Territorial Planning for Coastal Zones in Chile:The Need for Geographical-Environmental and Natural Risk Indicators for Spatial Decision Support Systems

Coastal zones are very dynamic and fragile environments, constituting a landscape ever more heterogeneous, fragmented and with increasing levels of complexity due to the changing relationship between man and nature. Integrated coastal zone management therefore requires detailed knowledge of the system and its components, based—to a large extent—on technical and scientific information. However, the information generated must be in line with the political requirements necessary for decision-making and planning. Thus the use of indicators to give a simplified view of the many components of the territory, and at the same time to provide important information about patterns or trends, becomes a tool of the utmost importance. These indicators can be understood as measurable characteristics of the environment, which facilitate comprehension of the processes occurring at different scales and serve as a reference to inform the population and support decision-making. The aim of the present note is to demonstrate briefly the need to develop geographical-environmental and natural risk indicators to facilitate comprehension of the dynamic of spatial and temporal landscape patterns, particularly in coastal environments. This approach offers an historical summary of the natural, socio-economic and political processes which currently make up the territory, and which without doubt will continue to influence it in the future. At the same time, it is proposed that information should be integrated on the basis of this framework with a view to generating spatial decision support systems in a context of planning and integrated management of the coastal zones of Chile.

Adaptive Integrated Coastal Zone Planning:History,Challenges,Advances,and Perspectives

Coastal zones are dynamic,rich environments,now densely populated,and increasingly challenged by human and climatechange pressures.Effective long-term integrated coastal zone planning is needed to ensure sustainable environmental protection and economic development.In this study,we reviewed the history of coastal zone planning since its birth in the 1950s based on the literature retrieved from the Web of Science(Core Collection)from 2000–2023,then summarized the tools and spatial allocation methods commonly used in the planning process,and finally proposed potential solutions to the challenges faced.The results show that after decades of development,coastal zone planning has changed from a decentralized activity to a targeted and integrated one,with an increasing emphasis on the ecosystem approach and the use of multiple planning tools.Spatial analysis techniques and environmental modelling software have become increasingly popular.Linear programming and overlay analysis are common approaches when performing spatial optimization,but land-sea interactions and planning in the marine parts still lack in-depth analysis and practical experience.We are also aware that the challenges posed by the integration of administrative hierarchies,scoping and conservation objectives,stakeholder participation,consideration of social dimensions,and climate change are pervasive throughout the planning process.There is an urgent need to develop more flexible and accurate spatial modelling tools,as well as more efficient participatory methods,and to focus on the holistic nature of the land-sea system to create more resilient and sustainable coastal zones.

Multi-scenario Simulation and Spatial-temporal Analysis of LUCC in China's Coastal Zone Based on Coupled SD-FLUS Model

Increased human activities in China's coastal zone have resulted in the depletion of ecological land resources.Thus,conducting current and future multi-scenario simulation research on land use and land cover change(LUCC)is crucial for guiding the healthy and sustainable development of coastal zones.System dynamic(SD)-future land use simulation(FLUS)model,a coupled simulation model,was developed to analyze land use dynamics in China's coastal zone.This model encompasses five scenarios,namely,SSP1-RCP2.6(A),SSP2-RCP4.5(B),SSP3-RCP4.5(C),SSP4-RCP4.5(D),and SSP5-RCP8.5(E).The SD model simulates land use demand on an annual basis up to the year 2100.Subsequently,the FLUS model determines the spatial distribution of land use for the near term(2035),medium term(2050),and long term(2100).Results reveal a slowing trend in land use changes in China's coastal zone from 2000–2020.Among these changes,the expansion rate of construction land was the highest and exhibited an annual decrease.By 2100,land use predictions exhibit high accuracy,and notable differences are observed in trends across scenarios.In summary,the expansion of production,living,and ecological spaces toward the sea remains prominent.Scenario A emphasizes reduced land resource dependence,benefiting ecological land protection.Scenario B witnesses an intensified expansion of artificial wetlands.Scenario C sees substantial land needs for living and production,while Scenario D shows coastal forest and grassland shrinkage.Lastly,in Scenario E,the conflict between humans and land intensifies.This study presents pertinent recommendations for the future development,utilization,and management of coastal areas in China.The research contributes valuable scientific support for informed,long-term strategic decision making within coastal regions.

Can We Manage Coastal Area? Will We?——The Institutional Change of the Coastal Area Management of Taiwan

The Coastal Zone Management Act was finally promulgated in 2015,while Ministry of the Interior was asked to draft a coastal management act in 1991 by Executive Yuan.It was until the government’s lifting of martial law in 1987,vigorous activities started prevailing on coastal areas.And relevant legal documents were on sea reclamation for development in the 1980’s by Council of Agriculture.The approval of“Taiwan Coastal Area Natural Environment Protection Plan”showed an era of environmental protection in 1980s.However,it was surely not market driven,similar to land development,but some efforts by the administration systems.Through all the years,the efforts were put on drafting plans and these efforts were not quite sounding.The coastal disasters and further climate change caught the attention of relevant NGOs,scholars,politicians,and the society.At the critical juncture the government was made to react to outside demands.And then the Coastal Zone Management Act was passed by Legislative Yuan,establishing an integrated coastal management system in Taiwan.As such,it is proposed to look into this long process of the attempt with the concept of institutional change in order to understand this coastal environmental preservation and protection issue in a broader scope.

Achievements,challenges,and recommendations for waterbird conservation in China's coastal wetlands

China’s coastal wetlands provide breeding,migration stopover,and wintering habitats for about 230 waterbird species,which is more than a quarter of all waterbirds in the world.Large-scale and high intensity human activities have resulted in serious loss and degradation of coastal wetlands over the past half century,causing population declines in many waterbirds.Through a literature review and expert surveys,this article reviews conservation measures taken in recent decades to protect waterbirds in China’s coastal wetlands and provides recommendations for future conservation action from three aspects:policy and administration,habitat conservation and management,and multiparty participation.Over the past decades,many conservation legislation,regulations and action plans at the national level and more site-specific measures and interventions have been implemented,with notable improvement in the effectiveness in policy making and multi-stakeholder participation.Accordingly,some threats to waterbirds have been mitigated and many key sites for waterbirds have been designated as strictly protected nature reserves.However,some critical issues still remain,mostly related to habitat conservation and management,such as coastal wetland restoration,control of invasive Spartina alterniflora,control of environmental pollution,and improvement of artificial habitat quality.We highlight that protecting natural tidal wetlands and improving habitat quality are critical for the conservation of coastal waterbirds,especially those highly dependent on the intertidal wetlands.China has demonstrated strong commitment to ecological conservation and restoration for the future,in terms of both funding and policies for biodiversity and wetland ecosystems.It is important that this commitment to conserve coastal waterbirds is supported continuously by science-and evidence-based decisions and actions.

Whether human-induced activities could change the gradient pattern of coastal land use along the sea-land direction:a case study in Manila Bay,Philippines

Increasing intense human activities have largely changed the coastal landscape and caused many environmental issues.However,whether human-induced activities could change the coastal land use gradient pattern,an important coastal zonal characteristic along the sea-land direction,remains unclear.Manila Bay was selected as the study area in this work.According to the distance of the land use and land cover(LULC)to the coastline,we clustered the typical coastal land use sequence patterns(CLUSPs)along the sea-land direction between 1988 and 2016 in Manila Bay and found the following.(1)Four typical CLUSPs,including the natural CLUSP dominated by forest land and grassland,the agricultural CLUSP dominated by dry farm and paddy field,the urbanised CLUSP dominated by construction land and the fishery CLUSP dominated by fishing farm,were mined in 1988.Three typical CLUSPs(a natural CLUSP,an intermediate CLUSP between the agricultural and urbanised CLUSPs,and a fishery CLUSP)were mined in 2016.(2)Affected by the dominant LULC,these typical CLUSPs showed a regular spatial pattern along the sea-land direction.For example,the typical natural CLUSP showed a landward pattern due to the long distance between the forest land and grassland and the coastline.(3)However,influenced by urban and aquaculture expansion,the land intensification of the CLUSP exhibited an obvious increase and caused the decrease of the CLUSP diversity from 1988 to 2016.The increase in the area of LULC coverage showed no obvious correlation with its distance from the coastline(DFC),but the net increase rate of LULC coverage had a significant negative correlation with the DFC.Therefore,human-induced activities have a large impact on the gradient pattern of coastal land use along the sea-land direction.

SALT WATER INTRUSION AND THE COUNTERMEASURES IN SOME COASTAL CITIES OF CHINA

This paper presents the general characteristics of salt water intrusion into surface water and groundwater in several coastal cities of China, methods of salinity calculation, prediction as well as the countermeasures for the prevention of salt water intrusion.

Model calculating annual mean atmospheric dispersion factor for coastal site of nuclear power plant

This paper describes an atmospheric dispersion field experiment performed on the coastal site of nuclear power plant in the east part of China during 1995 to 1996. The three-dimension joint frequency are obtained by hourly observation of wind and temperature on a 100m high lower; the frequency of the 'event day of land and sea breeze' are given by observation of surface wind and land and sea breezes; the diffusion parameters are got from measurements of turbulent and wind tunnel simulation test. A new model calculating the annual mean atmospheric dispersion factor for coastal site of nuclear power plant is developed and established. This model considers not only the effect from mixing release and mixed layer but also the effect from the internal boundary layer and variation of diffusion parameters due to the distance from coast. The comparison between results obtained by the new model and current model shows that the ratio of annual mean atmospheric dispersion factor gained by the new model and the current one is about 2.0.

Examining Health of Wetlands with Multiple Ecosystem Services as Targets in China’s Coastal Regions

Coastal zones are key interconnectors of terrestrial and marine ecosystems.Due to the degradation and fragmentation of coastal wetlands,there is an urgent need to develop assessment methodology to compare the health of wetland ecosystems at different spatial scales.This will help efficiently develop and implement protections using easy-to-access ecosystem health data.This study aims to understand the spatial distribution of coastal and inland wetland health for China’s coastal regions.A Wetland Health Index(WHI)was developed to provide a basis for policy and decision making.Four utilization models—Long Term Model,Open Model,Nature Reserve Model,and Protected and Economic Model—were defined in the context of China’s coastal regions to specifically examine wetland health.Results show that the average WHI score was 63.6 with the range of 44.8–84.3 for 35 National Nature Reserves(NNRs),and the southern NNRs generally performed better than the northern NNRs.The wetlands in the southern provinces/municipalities are relatively healthier than their northern counterparts.The competent authority has slight influence on WHI scores but duration of conservation establishment does not show a clear correlation.With increasing economic activity,the differences in health conditions(WHI scores)of China’s coastal regions also increase.Gross Domestic Product(GDP)or economic intensification does not relate to WHI scores.Appropriate trade-offs between wetland management and economic development could contribute to improve health conditions,conservation and utilization of coastal and inland wetlands.

Activity Pattern and Habitat Use of Shorebirds in an Artificial Wetland Complex:A Case Study of Breeding Pied Avocet in the Yellow River Delta,China

With the loss of substantial natural wetlands in coastal zones,artificial wetlands provide alternative habitats for many shorebirds.Scientific management of artificial wetlands used by shorebirds plays an important role in maintaining the stability of shorebird population.Satellite tracking technique can obtain high-precision location information of individuals day and night,providing a good technical support for the study of quantitative relationship between waterfowls and their habitats.In this study,satellite tracking method,Remote Sensing(RS)and Geographic Information System(GIS)technology were used to analyze the activity pattern and habitat utilization characteristics of Pied Avocet during breeding period in an artificial wetland complex in the Yellow River Delta(YRD),China.The results showed that the breeding Pied Avocets had a small range of activity,with a total core and main home range of 33.10 km^(2) and 216.30 km^(2),respectively.This species tended to forage in the pond and salt pan during the day and night,respectively,with an unfixed staying time in the breeding ground.The distance between breeding ground and feeding ground was less than 6 km.It is emphasized that in addition to improving the conditions of the remaining natural habitats,effective managing artificial habitats is a priority for shorebird conservation.This research could provide reference for the management of artificial wetlands in coastal zones and supply technique support for the protection of shorebirds and their habitats,and alleviate human-bird conflicts and sustainable development of coastal zones.

Mangrove wetlands distribution status identification, changing trend analyzation and carbon storage assessment of China

This research investigates the ecological importance,changes,and status of mangrove wetlands along China’s coastline.Visual interpretation,geological surveys,and ISO clustering unsupervised classification methods are employed to interpret mangrove distribution from remote sensing images from 2021,utilizing ArcGIS software platform.Furthermore,the carbon storage capacity of mangrove wetlands is quantified using the carbon storage module of InVEST model.Results show that the mangrove wetlands in China covered an area of 278.85 km2 in 2021,predominantly distributed in Hainan,Guangxi,Guangdong,Fujian,Zhejiang,Taiwan,Hong Kong,and Macao.The total carbon storage is assessed at 2.11×10^(6) t,with specific regional data provided.Trends since the 1950s reveal periods of increase,decrease,sharp decrease,and slight-steady increases in mangrove areas in China.An important finding is the predominant replacement of natural coastlines adjacent to mangrove wetlands by artificial ones,highlighting the need for creating suitable spaces for mangrove restoration.This study is poised to guide future mangroverelated investigations and conservation strategies.

COASTAL AND PORT ENGINEERING IN CHINA

In this paper, a brief account of the characteristic features of the coast of China is given, followed by the present status and future prospects of coastal and port engineering in China, experiences gained and problems encountered. China has attached much importance to the rehabilitation and modernization of war damaged existing ports and the construction of new ports, as well as the maintenance and strengthening of coast protection works.

Coastal Risk Management in a Context of Climate Change: A Case Study of Kribi Town of the South Region of Cameroon

Coastal zones are attractive areas for human habitation. Even though these areas are often associated with high disaster risk. This study is with objective to assess the legal and policy frameworks aimed at mitigating the disasters and risks associated with coast line degradation in Kribi. A desk review of the different policy documents related to coast line management and disaster risks mitigation were analyzed. Stakeholders involved in this coastline management were also consulted. The results of the study revealed that two types of actors are involved in coastline management namely: state actors and non-state actors. There are different legal instruments aimed at managing coastline in Cameroon that range from International to National laws with Cameroon ratifying some of these conventions such as: the Ramsar convention;the Convention on the Protection of Wetlands of International Importance;the Convention on Biological Diversity (CBD) and the United Nations Framework Convention on Climate Change (UNFCCC). In conclusion, Cameroon has a political will, legal and institutional framework for coastal zone management. However, initiatives designed to promote integrated coastal zone management are facing challenges in its implementation. The reasons are due to the complexity of the institutional and legal framework for the implementation of these initiatives. It is therefore necessary to develop an integrated management strategy that takes into account the role of each institution and that clearly defines an effective mechanism for intervention and coordination between actors.

Diversity and distribution of bacterial community in the coastal sediments of Bohai Bay,China

In order to understand the diversity and distribution of the bacterial community in the coastal sediment of the Bohai Bay, China, high-throughput barcoded pyrosequencing of the 16S rRNA gene was used. Metagenomic DNA was extracted from the sediment samples, and was sequenced using a 454 GS FLX Titanium system. At 97% similarity, the sequences were assigned to 22 884 operational taxonomic units （OTUs） which belonged to 41 phyla, 84 classes, 268 genera and 789 species. At the different taxonomic levels, both the dominants and their distribution varied significantly among the six coastal sediments. Proteobacteria was the first dominant phylum across all the six coastal sediments, representing 57.52%, 60.66%, 45.10%, 60.92%, 56.63% and 56.59%, respectively. Bacteroidetes was the second dominant phylum at Stas S1, S2 and S4, while Chloroflexi was the second dominant phylum at Stas S3, S5 and S6. At class level, γ-Proteobacteria was the first dominant class at Stas S1,S2, S4 andS6, while δ-Proteobacteria became the first dominant class at Stas S3 and S5. In addition, a large proportion of unclassified representatives have distributed at the different taxonomic levels. Canonical correspondence analysis （CCA） results indicated that the sediment texture, water depth （D）, dissolved oxygen （DO）, total nitrogen （TN） and nine EPA priority control polycyclic aromatic hydrocarbons （PAHs） including naphthalene, acenaphthylene, acenaphthene, fluorine, phenanthrene, fluoranthene, pyrene, benzo[a]anthracene and indeno[1,2,3-cd]pyrene were the important factors in regulating the bacterial community composition. Those results are very important to further understand the roles of bacterial community in the coastal biogeochemical cycles.

Study of coastal water zone ecosystem health in Zhejiang Province based on remote sensing data and GIS

The coastal ecosystem health assessment is a field of increasing importance.In this paper,a preliminary assessment of ecosystem health in Zhejiang coastal water zone was made,mainly based on remote sensing data and GIS technique.Its spatial and quantitative evaluation was facilitated by the progress of remote sensing and GIS technique development.Firstly,human activities,hydrology and ecosystem problems in the study area were discussed and analyzed.Secondly,from 4 aspects of human stress,physical,chemical and biological responses to anthropogenic activities and natural stress,several indicators such as water transparency（Secchi Disk Depth,SDD）,suspended substance concentration,dissolved inorganic nitrogen,active phosphate,chlorophyll,harmful algae bloom,as well as distribution of sewage,sea lanes and port were employed.Thirdly,the Analytic Hierarchical Process was used for indicator weight calculation,and the ecosystem health criteria were established according to the integrative analysis of national water quality criteria,similar coastal ecosystem health research in other places or data inherent properties.The results indicated that from 2005 to 2007 the coastal water ecosystem health value in Zhejiang Province was unhealthy and needs ecological restoration by human intervention.

Technical foundation research on high resolution remote sensing system of China's coastal zone

China's coastal zone is a region with a highly developed economy that contrasts clearly with the slow paced regular investigation on its natural environment,which cannot keep pace with the requirement of economic development and modern management.Laying a theoretical foundation for the modern management of China's costal zone is aimed at. This research focuses on the following processing and analyzing technologies for coastal zone high-resolution remote sensing data: organization and management of large amounts of high-resolution remote sensing data, quick and precise spatial positioning system,algorithms for image fusion in feature level and coastal zone feature extraction. They will form a technical foundation of the system. And, if combined with other research results such as coastal zone remote sensing classification system and its mapping subsystem, an advanced technical frame for remote sensing investigation of coastal zone resource will be constructed.

Denitrification in Qi'ao Island coastal zone,the Zhujiang Estuary in China

Samples of sediments and the overlying water were collected in the Qi＇ao Island coastal zone,the Zhujiang（Pearl River） Estuary（ZE）.Denitrification rates,sediment oxygen demand（SOD）,and fluxes of inorganic nitrogen compounds were investigated with N2 flux method,using a self-designed continuous flow through and auto-sampling system.The results indicate that the denitrification rates varied between 222 and 908 μmol/（m2·h） with an average of 499 μmol /（m2·h）.During incubation,the sediments absorbed dissolved oxygen in the overlying water with SOD ranging from 300 to 2 363 μmol/（m2·h）.The denitrification rates were highly correlated with the SOD（r2=0.77） regardless of the NO-3＋NO-2 concentrations in the overlying water,organic carbon contents in sediments and water temperature,suggesting that the SOD was probably the main environmental factor controlling the denitrification in the Qi＇ao Island coastal zone.There was a net flux of NO-3＋NO-2 into the sediments from the overlying water.The NH＋4 flux from sediments into water as the result of mineralization was between 12.3 and 210.3 μmol/（m2·h）,which seems limited by both organic carbon content in sediment and dissolved oxygen concentration in the overlying water.

Construction and implementation of multisource spatial data management system of China's coastal zone and offshore

To meet the increasing demand of national spatial database infrastructure construction and application, a concept model of China's coastal zone scientific data platform is established based on the information feature analysis of a compound dataset, consisting of remote sensing data and conventional data. Based on this concept model, the detailed logical database structure and the storage strategy of remote sensing data and their metadata using ArcSDE are designed. The complicated technology of multisources data combination in this research is crucial to the future coastal zone and offshore database construction and practical running, which will provide intelligent information analysis and technological service for coastal zone and offshore investigation, research, development and management.

Quantizing and analyzing the feature information of coastal zone based on high-resolution remote sensing image

On the basis of realization of beach information and its differentiating of high-resolution remote sensing image on coastal zone, extracting objects are carried through RS multi-scale diagnostic analysis, and fast information extraction methods and key technologies are put forward. Meanwhile image segmentation methods are set forth for objects of coastal zone. And through the application of Otsu2D to the segmentation of water area and dock and the applying of Gabor filter to the separation and extraction of construction, some typical applications of high-resolution RS image are presented in the field of coastal zone surface objects＇ recognition. Quantizing high-resolution RS information on the coastal zone proved to be of great scientific and practical significance for coastal development and management.