Measures of spatial planning in the port areas at China’s border

The spatial planning for border port areas often requires consideration to the influence of cross-border bilateral exchanges and cross-border natural habitat ecosystems on territorial spaces, and implementation of national initiatives such as the “Community with a Shared Future” and the “Belt and Road Initiative”. The existing research on spatial planning focuses more on the administrative areas within a country and less on the cross-border regional connections. Also, existing literature regarding border port areas as typological research focuses more on economic and spatial development modes and less on the influence of ‘networks and flow’ on the territorial spaces. The author, based on the work practices in the land border areas in Yunnan and Jilin provinces as well as combining the theoretical concept ‘network and flow’ of Michael Batty, describes the features of cross-border flow network by use of border effect framework, researches the key considerations for the spatial planning for cross-border areas in the new era of spatial planning system construction, and initially provides optimization measures exampled by specific cases, which can be used as reference for the spatial planning for cross-border areas at all levels.


Research overview
The border port areas of China connect and utilize "two markets and two kinds of resources" at home and abroad.They are where the "Community with a Shared Future for Mankind" initiative takes root and sprouts . 1 The "Community with a Shared Future for Mankind" transcends nations and states to view the future for mankind and is constructed from five aspects: politics, security, economy, culture and ecology.It emphasizes "joint response to security issues among nations, political exchanges beyond ideology, economic interdependence, and mutual benefit and win-win results".The land border port areas that the author focuses on in the paper are the gateway to the outside world.The future development opportunities lie in strengthening cross-border cooperation with neighboring countries to form a high-level cross-border flow, which is an important part of spatial planning.
The existing literature seldom considers port cities/towns or port areas as a special type of territorial space and seldom investigates the characteristics of cross-border flow of territorial space.The existing literature regarding spatial planning focuses more on a single administrative area or a specific area with some relevance.For example, Bai researched the special planning for the Yellow River Basin (Bai et al., 2020), Wang researched the planning priorities at the township level (Wang et al., 2020, b), and Wang, Chen and Han researched the planning priorities at the city and county level (Wang et al., 2019).The existing literature on border port areas mostly focuses on the overall characteristics, industrial development modes, and the like.For example, Xiao summarized the basic change characteristics and spatial development modes of the border port areas of China from 2000 to 2010 and rendered the city/town cluster system network expressed by point-line system (Fig. 1) (Xiao, 2016).
After Manuel Castells put forward the theory space of flows (Castells, 1996), network-related research based on social network data (Hong & Luo, 2020), corporate branch data (Le et al., 2018), train frequency data, etc. gradually appeared.Michael Batty has a more comprehensive discussion on the theory and model of network and flow.He believes that "the pattern characteristics of urban growth and form are closely related to various interactions, energy flows and information flows" (Batty, 2019).
In the era of globalization, China continues to open up along the border.In the land border port areas adjacent to other countries, there exists that "the existence of state power makes the border affect the cross-border economic behavior (Li, 2014) ", that is, the "border effect", which is a general term of both border intermediary effect and intermediary isolation effect.Intermediary effect is a phenomenon that "border promotes spatial interaction", while isolation effect is a phenomenon that "border hinders spatial interaction (Li, 2014)".Due to the border intermediary effect (i.e., the prominent characteristics of cross-border flow), it is more in line with the basic characteristics of the open development of border ports to perceive the locations and patterns of port areas from the perspective of "network and flow".
Cities in border port areas originated from the defense, commercial trade, and transportation demands of border resident (Liu, 2009).The driving force of urbanization is "commercial trade and tourism, logistics distribution, goods processing" and other functions.Zhang divided land border port areas into northeast (Zhang & Shi, 2017), northwest and southwest areas, where the ports are common in urbanization degree, economic development stage and industrial structure: they usually rely on the primary and tertiary industries at the initial stage, with the speed of industrialization usually slower than that of urbanization.The port cities/towns in the northeast area enjoy a good industrial foundation, with an urbanization rate over 60%, or even over 90% somewhere.However, the southwest and northwest areas suffer a generally low level of industrialization and urbanization.Although the cities/towns in the border port areas are in different stages of urban development, the urbanization rate is generally higher than that in the surrounding areas (Lu & Zhang, 2016).
Ports and cities/towns are in a spatial relationship of "separation of ports and cities/towns" and "connection of ports and cities/towns"."Connection of ports and cities/towns" is often manifested as "one city/town for two countries" and "one village for two countries", that is, the cities/towns or villages where the people of the two countries live are close to each other, such as the Muse-Ruili Port on the China-Myanmar border and the Lào Cai-Hekou Port on the China-Vietnam boarder.

Cross-border network features under border effect
The paper mainly focuses on the explicit geographic networks involving land border port areas, such as the infrastructure network and ecological network where flow of people and goods and flow of animals exist, leaving alone the implicit networks where financial capital flow and information flow exist.

Infrastructure network
Thanks to its continuous advocacy of border opening and multilateral cooperation in the world pattern in recent years, China sees gradually-highlighted and rapidly-growing advantages in cross-border land transportation2 It enjoys a rapid increase of the number of cross-border highways and railways, overseas storage spaces, energy transmission network lines allowing faster transmission rate (Ma et al., 2020), and an increasingly strengthened centrality of land border ports in cross-border logistics networks.Cross-border railways/highways connect border port cities/towns with major Chinese and foreign cities and seaports, so that transportation costs (on time and price) are continuously reduced and corporate capital turnover and economic benefits are continuously improved.At present, the ports in the southwest area can be connected with the world through cross-border logistics networks3 such as China-Europe (Vietnam) railway express and China-ASEAN shuttles (Fig. 2).

Cross-border ecological network
Ecosystems are interconnected across borders, not separated by borders.Two neighboring countries are often in an ecosystem, like the upper and lower reaches of a river basin.Cross-border ecological flows include air flow, water flow, animal flow, etc. Problems on one side will affect both sides.For example, air pollution may affect the air quality of neighboring countries due to wind direction and other reasons, but the bearers of the costs on cross-border pollution control are not very clear about that.Although burning wasteland in Indonesia, for example, can enhance fertility and economic benefits of land, it brings air pollution to neighboring Singapore, so it is a potential danger to residents' health and aviation safety, leading to inestimable subsequent losses (Table 1).
China's border port areas are usually rich in biological populations, and the border isolation effect brings certain damage to biodiversity: due to the existence of separation net on border or the difference in protection efforts on both sides, the cross-border migration of animals is hindered, the habitat is reduced, and their survival rate is affected, which may lead to the invasion of animals to human villages and farmlands, causing loss of human life and property.For example, the Siberian tigers on the China-Russia border and the Mongolian gazelles on the China-Mongolia border have been reduced in number as a result of failure to migrate across the borders; there are also conflicts arising from the overlap between the living space of the Asian elephants and that of the local people on the China-Laos border.

Transnational production capacity cooperation
Transnational production capacity cooperation4 can promote the adjustment, transformation and upgrading of domestic industrial structure, drive the employment and economic development of neighboring countries, and significantly promote export trade (Batty, 2019), forming a win-win situation.The vast hinterland of capacity cooperation is mainly to guide (export-oriented) processing and manufacturing enterprises to reasonably allocate industrial chain links at home and abroad, gather along the economic integration corridor, and then form a linkage between domestic and foreign parks, with the purpose to obtain the added value of the upstream of the industrial chain (such as Van Trung Industrial Zone in Bac Giang Province, Vietnam, invested by Chinese enterprises).
The content of cross-border production capacity cooperation tends to be diverse, involving agricultural products, electric vehicles, high-tech industries, infrastructure, energy, etc.In terms of cross-border agriculture, the ASEAN countries in the southwest border area such as Myanmar, Vietnam and others and China (China is in the temperate region, and ASEAN countries are in the tropical region) are somewhat different in climate and natural resources, so they are mutually complementary in agricultural products and agricultural production technology, but suffer some problems such as "unsound market in agricultural areas, relatively simplistic forms, incomplete interconnection infrastructure, and non-tariff barriers" (Sun & Wang, 2020); cross-border tourism is a feature of future regional integration cooperation.It is a field that needs to promote the border intermediary effect -relying on the differences in cultural customs of both sides on the border, existing tax-free shopping centers and other conditions to start the cross-border tourism route construction; in terms of energy, Yunnan has become an international energy hub of South Asia and Southeast Asia, and a "regional internationalized energy security network" will be built there.The ASEAN countries face varying degrees of power shortage, while Yunnan can complement them thanks to abundant hydropower resources."Cloud power delivery" has helped solve the power shortage, also helped many hydropower companies cover their deficits, and promoted the prosperity and development of international power trade, bringing a new economic growth point to Yunnan (Fig. 3).

"Launch" of channel economy and integration of port and city/town
Integration of port and city/town 5 is the embodiment of production capacity cooperation layout in the port areas, the choice by market and the demand of port urbanization.Pilot free trade zones, cross-border economic cooperation zones, and comprehensive bonded zones settling in the border port areas 6 are the space of the ports where cross-border production capacity cooperation is implemented.Since 2020, China has vigorously guided the development of port urban areas, continued to expand the opening of border areas, and established three pilot free trade zones at the land border ports in Yunnan Province, Heilongjiang Province and Guangxi Zhuang Autonomous Region, including Honghe area, Dehong area and Kunming area in Yunnan, Nanning area, Chongzuo area and Qinzhou Port area in Guangxi, and Harbin area, Heihe area, and Suifenhe area in Heilongjiang, mostly located in port cities/towns.

Mutual promotion of border trade and tourism
The border trade is active 7 and have been gradually upgrading to form a processing trade industrial chain and industrial clusters.The gathering of people and the The concept of port-city/town integration focuses on the economic and industrial integration of cities/towns, which is a policy concept often adopted in border cities/towns. 6Bonded area and the like enjoy the highest degree of policy preference for pilot free trade zones and serve as the space where the cooperation of cross-border areas is implemented.Cross-border economic cooperation zone is one of the links between the "Belt and Road" Initiative of China and the "Two Corridors and One Circle" Planning of Vietnam.Bonded warehouse is a commodity transfer station of cross-border logistics e-commerce.
Comprehensive bonded zone is managed by the customs, implements the tax and foreign exchange policies for bonded port areas, integrates the functions of bonded zone, export processing zone, bonded logistics zone and port, and can develop international transfer, distribution, procurement, entrepot trade, export processing, etc.
7 The General Administration of Customs of the People's Republic of China stipulates that "border trade is divided into trade between border residents (the participator is border residents) and small-volume border trade (the participator is enterprises with the right to operate small-volume border trade).The household goods (except those listed in the checklist of nonduty-free imported goods from trade between border residents in border areas) imported by a resident in border areas through the trade between border residents shall be exempted from import duty and import linkage tax as long as the value of such goods imported by each resident is not more than CNY 8000 per day.If the value is more than CNY 8000, the exceeding part shall be levied upon import duty and import linkage tax in accordance with the relevant provisions." different natural and cultural customs of the two countries also promote the development of cross-border tourism.At the Horgos Port on the China-Kazakhstan border, the largest duty-free shopping center of Northwest China has been established, and the Korgos China-Kazakhstan International Cultural Tourism Area has been established to develop characteristic border tourism and cross-border shopping tourism, all of which are the manifestation of the scale upgrading of small-volume trade.In addition, with the comprehensive construction of the New Eurasian Land Bridge Hub in terms of tourism, transportation, etc., the urbanization degree of Horgos has been rapidly improved.

Cross-border community
Population mobility is the result of the combined action of the thrust and pull of the original place to live and the place to immigrate (Wang et al., 2018).The neighboring countries are different in wages and consumption levels, and notice a striking phenomenon of cross-border communities8 in land border ports cities/ towns.

Cross-border labor market
Cross border laborers come to work in the urban areas of neighboring countries by signing agreements.The Pingxiang Port on the border of Guangxi and Vietnam and the Hekou Port on the border of Yunnan and Vietnam signed labor force agreements with the four northern provinces of Vietnam, with an annual labor force supply of 50,000 to 100,000 people 9 The Ruili-Muse port area on the border of Yunnan and Myanmar shows obvious characteristics of cross-border labor, with a large number of Burmese people doing business and working in Ruili all the year round (Fig. 4 and 5).

Cross-border ethnic exchange
For cross-border exchange between border residents, there must be a stable social network foundation, namely, cross-border intermarriage, cross-border trade, cross-border customs of the same ethnic group, and so on (Wang & Feng, 2020).Base on the culture of the same ethnic group, the lifestyle, habits, customs, language, architectural style, etc. reflect the commonality.For example, the culture of Pingxiang in Guangxi has a lot in common with that of Vietnam.Historically, the two sides influenced each other in religion, doctrine, social customs, and others and gradually tended to be similar (Wang, 2014).

Summary of features
The cross-border networks in the land border port areas are featured with intermediary and isolation effects with positive and negative influences (known as positive and negative effects) (Table 2).The layout optimization in the spatial planning needs to focus on the positive border effects, including the positive intermediary and isolation effects, minimize the negative intermediary and isolation effects, and appropriately transform the negative effects into positive effects.3 Optimization focuses and measures

Adoption of multiple measures for implementation of industries in port cities/towns
Border ports are close to the markets of neighboring countries, and the key is to continuously identify and allocate advantageous resources so as to generate and maintain advantages in the changing market.The first is to promote port development and strengthen port-city/ town interaction.In the early stage of construction, port cities/towns generally become the economic "channels".Whether a local area has sustainable impetus to develop port economy depends on the possibility of attracting industrial clusters that match the import and export trade of the port.The second is to develop the industries in line with the trade trends of the neighboring countries.For example, the comprehensive bonded zone in Honghe Prefecture of Yunnan Province, the State-level Mengzi Economic and Technological Development Zone, and the cross-border economic cooperation zone  between Hekou of China and Lào Cai of Vietnam have implemented "three-zone linkage" to form Vietnamoriented mechanical equipment manufacturing, electronic equipment manufacturing and other industries demanded by Vietnam.The last is to highlight new industrial modes and promote the deepening and popularization of the application of the Internet in import and export trade (e.g., the cross-border social platform e-commerce at the Ruili-Muse Port connects online and offline transactions and also helps maintain the growth of Ruili jade import and export trade during the epidemic).

Reduction of element flow costs
The ways to reduce the element flow costs include: first, continue to upgrade the border trade infrastructure, which has a positive effect on cities/towns, that is, improving the scale of urban freight transportation, enhancing the level of internationalization, and attracting cross-border tourists and cross-border floating population; second, establish overseas warehouses and other overseas storage nodes, provide border trade express 10 and make other efforts, which help reduce transportation costs and improve efficiency; third, make port facilities convenient, electronic and centralized to facilitate port customs clearance.

Case 1: building of one city/town for two countries by China and Myanmar
The Ruili-Muse port area on the China-Myanmar border, located at the node hub of the "Bangladesh-China-India-Myanmar Economic Corridor" and the north-south "China-Myanmar Economic Corridor", is the traditional route and main channel of Myanmar-China economy and trade.Muse-Ruili, through the construction of the "one city/town for two countries", has strengthened the interconnection between the two cities/towns in the port are, including the establishment of cross-border economic cooperation zone, the focusing on import and export processing and manufacturing base that match the goods import and export structure of the port, international logistics storage areas, among others (Fig. 4 and 5), and the improvement of the efficiency of cross-border element flow and connection by provision of more expressways and highway bridges, so as to realize a higher degree of port-city/town integration and ultimately form a cluster growth pole shared by China and Myanmar.
In 2018, the Ruili Port has grown into the port with the largest flow of people and goods in China, and the Muse Port is the largest port in northern Myanmar and the port area accounting for the largest proportion of Myanmar-China border trade 11

Joint protection of cross-border green ecology
The governance of cross-border ecological environment system is to build a community with a shared future for mankind where mountains, rivers, forests, farmlands, lakes and grasslands are in a harmonious relationship with mankind, and to implement the concepts of green "belt and toad initiative" and "ecological civilization" advocated by China.Ecological elements influence and restrict each other and are closely related through material conversion and energy flow, so the national border isolation effect should be eliminated to the greatest extent.Breaking the isolation effect of ecological elements often encounters hindrance: pressure on ecological environment protection in border port areas brought by urbanization demands such as population and construction volume increase, hydropower construction, mine development, etc. (Wang, 2014), which not only occur on the border, but may also exist in the hinterland involved.River basin is the main spatial form of crossborder ecological network and the main position of cross-border economic cooperation and development.Although the construction of dams in the upstream countries of a river basin, resulting in the interruption of space and the reduction of water flow, improved the utilization rate of water resources in the areas of the dams and eliminated the impact of flooding on cities/ towns, it affected the agricultural irrigation and food security of downstream countries, bringing knock-on effects such as soil erosion, reduction of biodiversity, reduction of fish migration, etc. (Wang et al., 2020, b).

Establishment of a coordination mechanism between ecology and urban development
Due to the inconsistency of development and protection standards between the two sides, over-development by one side may lead to such problems as damage to overall ecological benefits and reduction of biodiversity.
10 Trade express is an "e-commerce plus trade between border residents" transportation mode, which is innovative and conducive to the reduction of cross-border logistics cost by the way of online application, government inspection and carpooling.Countries on both sides of the border should establish a communication mechanism to eliminate information asymmetry and unify standards.River basin cooperation is often a common form of transnational cooperation, such as the Lancang-Mekong cooperation, the Greater Mekong Sub-region (GMS) development planning, etc., to coordinate the allocation of water resources in the river basin, establish dialogue mechanisms for tourism cooperation, environmental protection, etc. (Fig. 6).

Ecological protection, restoration and pollution control of cross-border mountains, rivers, forests, farmlands, lakes and grasslands
Cross-border grassland governance, cross-border mountain development and protection, cross-border desertification and rocky desertification governance, and cross-border wetland protection are carried out in collaboration with neighboring countries.In addition, cross-border highrisk natural disasters such as natural disasters and manmade accidents, cross-border forest and grassland fires, and special dangerous infectious diseases require both sides to share information and actively carry out technical exchanges and cooperation in the field of ecological environment protection, jointly organize environmental protection research, and establish unified protection standards.The cost of cross-border environmental pollution control is high, and it is difficult to hold accountability if the rights and responsibilities are not well defined, so it is a must to prevent such issues as far in advance as possible, clarify the rights and responsibilities and quantify the cost.

Protection of cross-border migration corridors for organisms
Conservation of living space for cross-border migratory organisms -the strategies for protecting the living space for cross-border migratory organisms include: to maintain cross-border ecology, relevant neighboring countries need to sign a memorandum of cooperation on wildlife protection, and establish a long-term cooperation mechanism for comprehensive protection of migratory animals' reproduction, living conditions, etc. in activity routes, wintering places, habitats, and estivating places.They should monitor animal action routes and, on such basis, delimitate cross-border organism corridors and food source bases, build buffer zones, and set up early warning mechanisms.

Case 2: measures for joint protection of ecology in the Changbai Mountain area
The Changbai Mountain area on the border between China and North Korea (near the Antu Shuangmufeng Port) plays an important role in the regional ecology12 There are differences in the protection of the Changbai Mountain between China and North Korea (Fig. 7), which affects the overall ecological benefits of the Changbai Mountain and makes it difficult to meet the requirements of protection and development of the Changbai Mountain (Wang & Zhang, 2020).The feasibility of joint collaborative protection of ecology depends on the clear definition of responsibilities, the establishment of crossadministrative boundary and cross-border protection mechanisms, and the combination of ecological and economic benefits: the Changbai Mountain cross-border tourist ring and the urban ecological rotating protection mechanism are that: take the developed cites/towns as coordinator and protector in ecological protection, and develop for protection; ensure the integrity of the ecosystem, while ensuring the overall control and coordination of local economic and social benefits, and strive for a balance between ecological and economic benefits.

Collaborative governance of cross-border society
Collaborative governance of cross-border society includes: ensuring safety control of and supporting services for floating population, exploring to establish cross-border data flow mechanism, promoting border protection and consolidation by vitalizing border areas and enriching the people living there, promoting cultural identity and building cross-border communities.

Exploring to establish cross-border data flow mechanism, and ensuring safety control of and supporting services for floating population
A McKinsey report13 points out that data flow indirectly promotes the "cross-border exchange of resources such as goods, services, and capital, and its contribution to global economic growth surpasses traditional cross-border trade and investment." At present, the cross-border data flow mechanism is still in the exploratory stage, and the issues to be solved include unifying national security impact assessment standards, determining national security due diligence and burden of proof, etc.14 to support the integration, electronization, and facilitation of cross-border floating population information15 so as to understand the scale demand of cross-border tourism facilities, the direction and trend of industrial development, and so on.Territorial space is likely to become the foothold of such mechanism.

Promoting border protection and consolidation by vitalizing border areas and enriching the people living there
Strategies and significance of collaborative border security control: carry out activities to vitalize border areas and enrich the people, use incentive measures to promote the implementation of subsidies for border residents, reward and support meritorious persons who participate in border control, patrol and defense, and encourage small-volume border trade, trade between border residents, and other commerce and trade industries, which are conducive to improving bilateral mutual trust and thus maintaining border stability; carry out digital control, and launch the strategies such as joint face-based defense mechanism, around people, villages, channels, documents and borders; in addition, carefully handle the removal and merger of the border villages guarding border security.

Promoting cultural identity and building cross-border communities
One of the driving forces for the development of border trade in border port cities/towns is to increase cultural identity and promote mutual understanding between the people in cross-border areas, that is, closer peopleto-people ties.More large-scale festivals, sports events, and daily bilateral cultural performances can be carried out, such as cross-border horse racing and the Pauk-Phaw Festival under the concept of the sports "belt and road initiative" (Xiang, 2018) which have promoted the development of tourism industry to a certain extent; In addition, by sharing high-quality resources and building cross-border communities, the people are provided with better cultural, educational, medical and health resources, the SMEs and individuals are given a better business environment, so as to fully promote the development of individuals and groups in both countries and the recognition of neighboring countries.

Case 3: social co-governance under river basin cooperation and sub-regional cooperation mechanisms
As a mechanism, river basin cooperation not only strengthens industrial and economic cooperation in the river basin, but also shares data such as water regimes.It, in a coordinated manner, helps solve ecological problems, focuses on poverty reduction, agricultural cooperation and other issues.It is a comprehensive transnational cooperation dialogue mechanism (Xiang, 2018) (Fig. 8).
The Lancang-Mekong cooperation provides a cooperation framework for the social governance of cities/towns in the river basin.The Lancang-Mekong River flows through China, Myanmar, Laos, Thailand, Cambodia and Vietnam.There are water resources imbalance and water resources allocation problems, and the need for water pollution control dialogue and economic cooperation.The content of the "3+5 Cooperation Framework" of the Lancang-Mekong Cooperation defines three pillars, namely, political security, economic and sustainable development, and society and culture, mainly involving interconnection, production capacity, cross-border economy, water resources, agriculture, poverty reduction, and other directions (Zhang & Shi, 2017).

Summary
An optimizable content framework is established with preparation tasks and objectives as guidance according to the Guidelines for Municipal and County-level Spatial planning (Fig. 9).
Territory space is divided into urban space, ecological space and agricultural space according to spatial layout, and into national and provincial space, municipal and county-level (prefecture-level) space, and township-level space according to spatial scale.The spatial layout structure can be represented by hub node (cluster growth pole), line (axis, corridor) and plane (functional area with

Integration into the concept of the community with a shared future, as reference for location positioning
From the perspective of regional cooperation, it is necessary to consider the importance of each type of location.
According to Michael Batty's description of network and flow, location is "a comprehensive result of what happens in the network and how various activities interact (Zhang, 2016)".Urban network can be divided into two levels: urban cluster network and urban internal network.The cognition of the economic, ecological and social aspects of cross-border flow network can effectively supplement the cognition of ecological, economic and social aspects of land border port area.As a part of the current network analysis, the analysis of cross-border network mainly affects spatial planning in the following aspects: regional strategic positioning and objectives, spatial layout, industrial planning, determination of ecological pattern and ecological space, and development of spatial control and governance strategies.
The concept of the community with a shared further contains the "mountains-rivers-forests-farmlands-lakesgrasslands community of shared life" and the "community with a shared future for mankind", which is a powerful concept supporting the opening-up and cooperation of countries in the era of globalization.The research on cross-border spatial planning is a specific way to integrate the concept of the community with a shared future into spatial planning.The cognition of cross-border flow

Integration into the industrial planning, as reference for "determination of city/town according to production"
To research the industrial development trend of a port city/town, it is necessary to examine the development trend of the cross-border industrial economic network related to the space.With the improvement of the economic integration degree of China's land port border areas and the neighboring countries, the location of the border areas has turned from "marginal areas" to "core areas", and then improved market proximity, market potential and market scale to attract "elements to flow to the border" (including labor, enterprises, capital, etc.) (Li, 2014).

Optimization of ecological protection and restoration and ecological pattern
Spatial planning requires overall optimization of the spatial layout of ecology, agriculture, cities/towns, etc.In terms of border port areas, it requires not only the governance of the mountains-rivers-forests-farmlands-lakes-grasslands system, but also the coordinated governance of the cross-border mountains-rivers-forestsfarmlands-lakes-grasslands system.For spatial planning, it is required to cognize the truly complete ecosystem of border port areas, consider the cross-border ecological pattern and its flow characteristics, and in a coordinated manner outline the ecological pattern on the basis of the overall cooperation with neighboring countries; in addition, water resources are a major obligatory target for the development of territorial spatial space, that is, "basing city/town, people, population and land on water resources", and are the most important and basic crossborder ecological flow in land border port areas.The cognition of cross-border river basin networks can also help determine the protection and development potential of water resources and conduct water resource risk assessment.

Optimization of urban health examination assessment index system to improve the effectiveness of territorial space governance
Cross border flow can help establish personalized indices for health examination assessment of spatial planning, so as to optimize the governance capacity of spatial planning.Border port cities should focus on increasing the indices regarding "coordination, openness, security, and sharing 16 "to accurately reflect the "cross-border characteristics".Due to different endowments and starting points of cities, in addition to the standards unified nationwide, there should be personalized indices to measure the assessment and accurately reflect the urban signs to timely diagnose "urban diseases", so as to better develop, implement and dynamically maintain spatial planning.

Fig. 1
Fig. 1 Schematic Diagram of City/Town Cluster System inside and outside China's Border and Locations of Border Port City/Town Cluster.Source: Xiao, 2016

Fig. 2
Fig. 2 Cross-border Highway-Railway Transportation -China-Europe Railway Express and China-ASEAN Shuttle Routes.Source: Provided by the author

Fig. 3
Fig. 3 Distribution of Energy Pipelines from Yunnan Energy Hub. Source: Provided by the author

Fig. 4
Fig. 4 Ruili-Muse and the Port on the Meeting Point of Two Economic Corridors

Fig. 5
Fig. 5 Industrial Layout Planning of Ruili-Muse and the Port Source: Provided by the author

Fig. 6
Fig. 6 Distribution of GMS Economic Corridor, River Basins and Dams near the Ports in Southwest China (Guangxi, Yunnan), and Ecological Protection Pattern of Yunnan Province as a Border Province.Source: Provided by the author

Fig. 7 (
Fig. 7 (Up) Dynamic Distribution of Forest Coverage Reduction in the Changbai Mountain Area on Both Sides of the Border Between China and North Korea and Distribution of Ecological Protection and Development Zoning Control Measures, (Lower-left) The border of China and North Korea at Tianchi Lake,(Lower-right) The Location of Mountain Changbai on the Heilong River Basin.Source: Provided by the author

Fig. 8
Fig. 8 Measures for Development of Cross-border Tourism in GMS.Source: Provided by the author

Table 1
China's Land Port Ports and Corresponding (National) City/Town Clusters

Table 2
Cross-border Flow Network Features under Border Effect 11According to the statistics of Dehong Prefecture of China, in 2016, the total trade volume of all ports of Dehong Prefecture with Myanmar reached USD 4.98 billion, accounting for 82.04% of the total trade volume of Yunnan with Myanmar and 40.51% of the total trade volume of China with Myanmar; in recent years, the import and export volume of the Muse Port with China continued to account for about 50% of the total import and export volume via land of Myanmar and about 75% of the total border trade volume of Myanmar.According to the statistics of Myanmar, the trade volume and tax revenue of 105 Mile Special Economic Zone of the Muse Port accounted for more than 80% of that of all land ports of Myanmar (source data: statistics of Myanmar Statistical Information Service and Kunming Customs).