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.

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.

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.

Construction and implementation of RS integrated application information system of China's coastal zone and offshore

The coastal zone and offshore are clearly of major economic and social importance, in thesame time it causes a series of problems of resources and ecosystem too. The research on and development of integrated application techniques for remote sensing provide not only a microcosmic and dynamic and synchronous technical means to the monitor, but also an integrated technical scheme to harmonically solve the ecological environment problem. The system is designed to focus on the application techniques of multi-sources remote sensing data. By developing remote sensing information extraction module, integrated user platform, and application module objected to the real ocean procedure for China' s coastal zone and offshore, the information system consists of the management of prodigious amount of data, display, analysis, simulation and output will be constructed and implemented. The final objective is to transform the research on ocean remote sensing into application.

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.

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.

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.

Assessing the Impact of Industrial Zones on the Environmental Pollution in Hai Phong’s Coastal Areas, Vietnam

Pollution in the coastal areas negatively affects biochemical indicators of seawater, human health and marine organisms. Hai Phong is a coastal city of Vietnam with the development of socio-economic activities, representing through an increasing number of industrial zones. This study is to evaluate the pollution of large industrial zones in Hai Phong city using numerical models. The numerical simulation (MIKE 21 SW, FM, ECO Lab) models were applied to simulate the wave propagation, hydraulic regime, water quality in coastal Hai Phong area. The MIKE 21 ECO Lab model was used to evaluate sources of waste from the large coastal industrial zones to some aquaculture zones. The calibration and validation results of wave propagation and the hydrodynamic models were resonably good, with Nash coefficient ranging from 0.65 to 0.90 and a percent bias (PBIAS) from 5.6% to 9.4%. The simulation results of water quality and concentration of pollutants (DO, BOD5, COD, TSS, Fe, and Coliform) in 2023 at the aquaculture locations show that the BOD5, COD, and TSS concentrations were higher than the allowable limits stated in the national technical regulation on surface water quality (QCVN 08:2023/BTNMT) and lower than the allowable limits stated in the national technical regulation on marine water quality (QCVN 10:2023/BTNMT). The outcomes of this study will provide more information to support managers to come up with a better socio-economic development plan for Hai Phong city to achieve sustainable development.

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.

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.

Spatial-temporal Characteristics of Land Use Intensity of Coastal Zone in China During 2000–2010

Based on remote sensing and GIS techniques, land use maps in 2000, 2005 and 2010 in China′s coastal zone were produced, and structural raster data of land use were further generated to calculate land use intensity comprehensive index(LUICI) for analyzing land use spatial-temporal characteristics at 1 km scale. Results show that: 1) from the perspective of spatial patterns of landforms at a macro scale, there is a significant difference in land use intensity between the north and the south of China′s coastal zone. Hotspots of changes mainly concentrated in metropolitan areas, estuaries and coastal wetlands; 2) elevation is an important factor that controlling land use spatial patterns at local scale. Land use intensity is much higher within areas below the elevation of 400 m and it decreased significantly as the elevation increasing; 3) there is a significant land-ocean gradient for land use intensity, which is low in island and near-shore areas, but high in the regions that 4–30 km far away the coastline because of much intensive human activities; however, in recent decades land use intensity had been promoted significantly in low near-shore area due to extensive sea reclamations; 4) significant differences of land use intensity were also found among provincial administrative units. A rising trend of land use intensity was found in provincial-level administrative units from 2000 to 2010. To sum up, elevation, land-ocean gradient, socio-economic status and policy are all influencing factors to the spatial patterns and temporal variations of land use intensity in China′s coastal zone.

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.

Impact of GCP distribution on the rectification accuracy of Landsat TM imagery in a coastal zone

The purpose is to explore the effect of the spatial distribution of ground control points （GCPs） on the accuracy of imagery rectification. Both area-distributed and linearly distributed GCPs were used to rectify a Landsat TM image of a coastal zone. Rectification accuracy was checked against 99 independent points over the intertidal mudflats with no ground control. Results indicate that the root-mean-square error of residuals over these areas is several times larger than its GCPs-measured counterpart. If the GCPs are spatially dispersed over an area, residuals fluctuate but increase steadily with distance to the source of control in easting （R^2= 0. 827）. in northing they fluctuate around 150 m until 15 km, beyond which they rise steadily at a small range of fluctuation. These residuals are less predictable from distance to the source of control than in easting （R^2= 0.517 ）. If the GCPs are distributed along a control line, residuals rise with distance to it linearly and predictably （R^2 = 0. 877） in the direction perpendicular to it. In a direction parallel to it, the distance has little impact on rectification residuals.

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.

Interpretation of the west segment of the coastal fault zone in the coastal region of South China based on the gravity data

By systemic processing, comprehensive analysis, and interpretation of gravity data, we confirmed the existence of the west segment of the coastal fault zone(west of Yangjiang to Beibu Bay) in the coastal region of South China. This showed an apparent high gravity gradient in the NEE direction, and worse linearity and less compactness than that in the Pearl River month. This also revealed a relatively large curvature and a complicated gravity structure. In the finding images processed by the gravity data system, each fault was well reflected and primarily characterized by isolines or thick black stripes with a cutting depth greater than 30 km. Though mutually cut by NW-trending and NE-trending faults, the apparent NEE stripe-shaped structure of the west segment of the coastal fault zone remained unchanged,with good continuity and an activity strength higher than that of NW and NE-trending faults. Moreover,we determined that the west segment of the coastal fault zone is the major seismogenic structure responsible for strong earthquakes in the coastal region in the border area of Guangdong, Guangxi, and Hainan.

The Coastal Zone Loess of the Liaodong Peninsula, Liaoning Province

This Paper discusses the origin of the Coastal Zone Loess on the Liaodong Peninsula, Liaoning Province.The loess is composed mainly of proximal materials transported by low-altitude air flow and less commonly ofinland distal materials carried by high-altitude air flow. The main provenance is the Liaodong Bay. When thesea level declined during glacial period, the bottoms of the Liaodong Bay and Bohai Sea emerged, wheredesertization occurred. As a result, submarine sediments were transported by strong northwesterly winds to theeastern coastal zone of the peninsula and deposited there. These materials mixed with the windblown dust car-ried by atmospheric circulation from the interior of the continent, forming the loess.

Analysis of Climate Change in the Coastal Zone of Eastern China, against the Background of Global Climate Change over the Last Fifty Years: Case Study of Shandong Peninsula, China

The climate change in Shandong Peninsula, China was analyzed in this paper by the non-parametric Mann-Kendall test, Accumulated Difference Curve and Order Cluster Analysis methods, based upon the datas of annual mean, maximum and minimum temperature and annual precipitation, precipitation from June to September over the past 50 years. Results obtained showed a number of observations: 1) The annual mean temperature of Shandong Peninsula showed a significant increasing trend, with a distinct abrupt change point detected around 1990, during the past 5 decades. The warming of the Peninsula over the last 50 years was due mainly to the significant increase of annual minimum temperature. The annual maximum temperature demonstrated a mixed trend of decreasing and increasing, but was statistically insignificant, and no abrupt change was detected;2) The annual precipitation exhibited a decreasing trend during the past 5 decades, with an abrupt change detected around 1980 at most stations;but there was an earlier transition point at 1966, at a few stations. The reduction in precipitation, from June to September, was responsible mainly for the decrease of annual precipitation. Besides, the proportion of the June-September precipitation in the year declined slightly over the last 50 years;3) In comparison, the temperature evolution in Shandong Peninsula was basically consistent with most parts of China, but warmed at a faster rate over the same period;the decreasing trend of precipitation was more significant compared with the other climate zones of China. Within the Peninsula, the abrupt change of temperature and precipitation in the Southeast was earlier than that in the Northwest;the reduction of precipitation was larger in the Southeast while the increase of temperature was more significant in the Northwest. This research was of great importance to understand the climate change and its environmental effects in the coastal zone.

Uncertainty and Sensitivity Analyses of the Simulated Seawater—Freshwater Mixing Zones in Steady-State Coastal Aquifers

The uncertainty and sensitivity of predicted positions and thicknesses of seawater-freshwater mixing zones with respect to uncertainties of saturated hydraulic conductivity, porosity, molecular diffusivity, longitudinal and transverse dispersivities were investigated in both head-control and flux-control inland boundary systems. It shows that uncertainties and sensitivities of predicted results vary in different boundary systems. With the same designed matrix of uncertain factors in simulation experiments, the variance of predicted positions and thickness in the flux-control system is much larger than that predicted in the head-control system. In a head-control system, the most sensitive factors for the predicted position of the mixing zone are inland freshwater head and transverse dispersivity. However, the predicted position of the mixing zone is more sensitive to saturated hydraulic conductivity in a flux-control system. In a head-control system, the most sensitive factors for the predicted thickness of the mixing zone include transverse dispersivity, molecular diffusivity, porosity, and longitudinal dispersivity, but the predicted thickness is more sensitive to the saturated hydraulic conductivity in a flux-control system. These findings improve our understandings for the development of seawater-freshwater mixing zone during seawater intrusion processes, and give technical support for groundwater resource management in coastal aquifers.

Coastal Zone Management Research in China under the Background of Marine Ecological Civilization Construction

With the proposing of the strategy of ＂maritime power country＂, as the hub of mankind contacting with ocean, the relationships between coastal zone and them were very close. To facilitate the development and protection of marine resources, taking coastal zone as research object, via collection and review of literatures, we firstly analyzed status quo of integrated coastal zone management in China and the problems in coastal zone management process, such as environmental pollution, ecosystem destruction and the occurrence of natural disaster, then illustrated the reasons for these problems, such as institutional, policy and legal deficiencies on coastal zone issue, and finally discussed the countermeasures enhancing coastal zone management by referring to construction experience of ecological civilization demonstration area under the background of ecological civilization construction, to promote ecological civilization construction in China and realize ＂maritime power country＂.

HY-1C Coastal Zone Imager observations of the suspended sediment content distribution details in the sea area near Hong Kong-Zhuhai-Macao Bridge in China

The impacts of the Hong Kong-Zhuhai-Macao Bridge(HKZMB)on suspended sediment content(SSC)were analysed in the Zhujiang River Estuary based on data from HY-1C,which was launched in September 2018 in China,carrying Coastal Zone Imager(CZI)and Chinese Ocean Color and Temperature Scanner on it.A new SSC inversion model was established based on the relationship between in-situ SSC and the remote sensing reflectance in red and near-infrared bands of CZI image.HY-1C satellite data obtained from October to December 2019 were applied to retrieve SSC in the Zhujiang River Estuary.The results show that SSC around the HKZMB is ranging from 20 mg/L to 95 mg/L.SSC change obviously on two sides of the bridge.During flooding and ebbing period,SSC increases obviously downstream of the bridge.SSC difference between upstream and downstream is ranging from 5 mg/L to 20 mg/L.Currents flowing across the HKZMB,the change trend of SSC in most places upstream and downstream is almost the same that SSC downstream of the bridge is higher than SSC upstream.The tidal currents interact with bridge piers,inducing vortexes downstream,leading the sediment to re-suspend downstream of the bridge piers.Other factors,including seafloor topography and wind,can also contribute to the distribution of SSC in the Zhujiang River Estuary.