The marine ecosystem services values for China based on the emergy analysis method

Ocean and Coastal Management 161 (2018) 66–73

Contents lists available at ScienceDirect

Ocean and Coastal Management journal homepage: www.elsevier.com/locate/ocecoaman

The marine ecosystem services values for China based on the emergy analysis method

T

Caizhi Suna,∗, Yiyao Wanga, Wei Zoua,b a b

Center for Studies of Marine Economy and Sustainable Development, Liaoning Normal University, 850 Huanghe Road, Dalian, 116029, China School of Foreign Languages, Liaoning Normal University, 850 Huanghe Road, Dalian, 116029, China

A R T I C LE I N FO

A B S T R A C T

Keywords: Marine ecosystem services Emergy Theil index Information entropy theory China

The purpose of this research is to acquire knowledge and understanding of the value of marine ecosystem services in China's coastal regions. This evaluation involved combining existing research results, based on the theory of ecosystem services and emergy analysis, estimating marine ecosystem services values in 11 coastal provinces and cities for each year from 2005 to 2014, and analyzing the changes in marine ecosystem services values over time and across regions. The results showed that the values had in general increased during the time the study was conducted, and that Hainan, Guangdong, and Shandong accounted for most of the value. Applying the Theil index to analyze the regional differences of China's coastal marine ecosystem services values, we found that these disparities had shrunk; intra-region disparities were the primary cause of this shrinkage, but the developments of marine ecosystem services values of both intra- and inter-regions were unbalanced. Changes in the marine ecosystem services structure in China's coastal regions from 2005 to 2014 were analyzed using the information entropy theory. Over time, the information entropy and equilibrium degree of China's coastal marine ecosystem services structure consistently showed a fluctuating uptrend; across regions, the information entropy of the marine ecosystem services in the 11 coastal provinces and cities had larger discrepancies. Our results reveal emergy analysis is a helpful method for assessing marine ecosystem services, and our database can serve as a basis for more studies the future. Our research has also revealed the problems existing in the development of marine ecosystem services in China, such as the imbalance in the development of marine ecosystem service values between regions and the differences in the degree of development of various services, which is crucial to the future development of the ocean.

1. Introduction The benefits humans derive directly or indirectly from ecosystem functions are called ecosystem services (Costanza et al., 1997). Building on this definition, Daily (1997) defined marine ecosystem services as the benefits provided to humans by the natural marine ecosystem and its ecological processes. In 1992, the United Nations Conference on Environment and Development emphasized that the sea was not only a key component of human life support systems, but also essential to sustainable development: The sea plays an important role in improving and balancing the global ecological environment. The marine ecosystem is one of the most productive, diverse, and valuable ecosystems on Earth (Souter and Linden, 2000; Spalding et al., 2001; Wilkinson, 2008); however, it is currently under threat worldwide due to a wide range of pressures, including unsustainable fishing practices, the development of tourism and urban infrastructure, pollution from landbased sources, ocean acidification, and sea level rise (Beharry-Borg and

∗

Corresponding author. E-mail address: [email protected] (C. Sun).

https://doi.org/10.1016/j.ocecoaman.2018.04.022 Received 4 October 2017; Received in revised form 29 March 2018; Accepted 22 April 2018 0964-5691/ © 2018 Elsevier Ltd. All rights reserved.

Scarpa, 2010; Cinner et al., 2012). This has resulted in significant losses and degradation of these important habitats, which in turn is likely to negatively impact the welfare and livelihood of people living in coastal areas (MA, 2005). Thus, assessing the value of marine ecosystem services is of strategic importance to furthering our understanding, development, and protection of the ocean and to promoting sustainable development. Because of the unique nature of the marine ecosystem, research methods used to study land ecosystems must be adapted when used to study marine environments. The sheer volume of marine life and the complexity of marine ecological processes are as yet beyond our technological capabilities to fully and completely evaluate (Zheng and Shi, 2009); therefore, it is difficult to develop appropriate measures to assess and compare marine ecosystem services in different areas. A number of studies that have attempted to assess the value of marine ecosystems at different scales have been published. Costanza et al. (1997) valued global marine ecosystem services at 20.9 trillion USD, which accounted

Ocean and Coastal Management 161 (2018) 66–73

C. Sun et al.

Implementing the principle of the Theil index, the disparities of values of marine ecosystem services were then disaggregated into intra- and inter-region disparities.

for 63.3 percent of the value of all global ecosystem services. Christie et al. (2015) assessed the benefits derived from alternative policy interventions and generated a wealth of evidence on the economic value created by the protection and enhancement of marine protected areas in St Vincent and the Grenadines. Brown and Hausner (2017) described and analyzed the distribution of cultural ecosystem values found in coastal areas in multiple countries, compared the results with noncoastal areas, and identified the type and intensity of ecosystem values located in coastal areas. In terms of China specifically, Chinese scholars have also been studying marine ecosystem services and functions since the beginning of the twenty-first century. Chen et al. (2006) used the marine ecosystem services evaluation framework proposed by Millennium Ecosystem Assessment (MA) (MA, 2005) to summarize and identify the elements of marine ecosystem services and established a classification system for Chinese marine ecosystem services. Xia et al. (2014) estimated the ecosystem services value of the Jiangsu offshore system and analyzed its regional distribution characteristics by applying national standards in the “Technical Directives for Marine Ecological Capital Assessment” (GB/T28058-2011) (General Administration of Quality Supervision, 2011). Shi et al. (2007) proposed a method for evaluating typical marine ecosystem services, and Xu and Han (2003) discussed a framework for estimating the value of marine ecosystem services. In view of the development and utilization of China's offshore ecosystem, a framework that could be used to evaluate the quality and value of marine ecosystem services was established (Chen et al., 2013). As evidenced by the aforementioned studies, domestic and international research focused on marine ecosystem service functions and value evaluation have been mostly confined to small geographic areas or single years and have been limited to assessing one or perhaps several marine ecosystem services values. Consequently, none have included a comprehensive and systematic analysis and evaluation of the value of marine ecosystem services. To fill this gap, we used Odum, 1996 emergy analysis method to assess the marine ecosystem services values for China's coastal regions, and then used the Theil index and the information entropy theory to further identify regional differences and structural changes in these values over time. The remainder of this paper is structured as follows. Section 2 describes the methodology of ecosystem services and the emergy analysis theory. Section 3 presents the calculations, regional differences, and structural changes to the marine ecosystem services value. Finally, Section 4 provides some concluding remarks.

2.2. Framework for valuing marine ecosystem services in China's coastal areas Several studies have proposed classification systems for ecosystem services. The first authoritative classification system was proposed by Costanza and his colleagues who divided ecosystem services into 17 types: gas regulation, climate regulation, disturbance regulation, water regulation, water supply, erosion control and sediment retention, soil formation, nutrient cycling, waste treatment, pollination, biological control, refugia, food production, raw materials, genetic resources, recreation, and culture (Costanza et al., 1997). According to Millennium Ecosystem Assessment (MA, 2005) research, ecosystem services can be divided into four classes: supply, control, social, and support. Chen et al. (2006) and Zhang et al. (2007) combined the particularities of the marine ecosystem and divided marine ecosystem services into 15 services. Using the aforementioned studies as a baseline, we broke down marine ecosystem services into four types and 15 subtypes: food production, raw materials, genetic resources (supply services), climate regulation, gas regulation, waste treatment, biological regulation, disturbance regulation (control services), recreation, cultural, scientific (social services), primary production, nutrient cycling, species diversity maintenance, and providing habitat (support services), but because support service is the basis of the other three types of services, this value was incorporated into each of the other three values we calculated (Chen et al., 2006; Zhang et al., 2007; Li et al., 2011; Lai et al., 2013). 2.3. Research method Emergy is the amount of flowing or stored energy that contains another kind of energy (Odum and Odum, 1987). It can be further explained as being the total amount of available energy applied directly or indirectly to the formation of a product or labor service (Odum, 1996). Emergy analysis is used to convert different kinds of energy into a uniform standard of measurement, thus facilitating comparisons and analyses of all types of energy; for further details on the derivation of emergy, see Lan et al. (2002). We assessed the value of the marine ecosystem services of 11 of China's coastal provinces and cities from 2005 to 2014. As the process of evaluating these services involves conducting research on the ocean, we began by defining the study area. China has sovereign rights to explore, develop, maintain, and manage natural resources in its exclusive economic zone, and so we used this study area for our research. The original data used for this analysis included information on marine fishing, mariculture, sea salt, ocean power, mangrove areas, and sea areas taken from China's Statistical Yearbooks (State Oceanic Administration People's Republic of China, 2006–2015), as well as data on algae obtained from previous years' Chinese Fishery Statistics Yearbooks (Bureau of Fisheries, Ministry of Agriculture, 2006–2015). The method used to calculate emergy was based primarily on the research of Odum (1996), Lan et al. (2002), Brown and Ulgiati (1997, 2002), and Meillaud et al. (2005). We used 9.44 × 1024sej/ a as the global emergy benchmark for our calculations, and the solar transformities of various substances and energy were based on the research results of Costanza et al. (1997) and Lan et al. (2002) (see Table 1 below).

2. Materials and methods 2.1. Study area China has about 3 million square kilometers under its jurisdiction, with abundant ocean resources and 5000 islands with areas greater than 500 m2. Its coastlines extend for 32,000 km, including 18,000 km along the continent and 14,000 km on island territories. Many ocean species live in these waters, and its oil and gas reserves exceed 400 × 108t and 14.09 × 1012m3 of oil equivalent (Zhang et al., 2003). These areas are also extremely rich in sand mineral resources (Lou et al., 2005). China's coastal provinces, municipalities, and autonomous regions (excluding Hong Kong, Macao, and Taiwan), from north to south, include Liaoning, Hebei, Tianjin, Shandong, Jiangsu, Shanghai, Zhejiang, Fujian, Guangdong, Guangxi, and Hainan. For the following analysis for the dynamic regional changes of marine ecosystem services values, these 11 coastal provinces and cities in China are separated into three major regions according to their location: the Northern region (Tianjin, Hebei, Liaoning, and Shandong), the Central region (Jiangsu, Shanghai, and Zhejiang), and the Southern region (Fujian, Guangdong, Guangxi, and Hainan). Therefore, the coastal areas can be divided into a three-level hierarchical structure: coastal China, three major regions of the coast (Northern, Central, and Southern), and the provinces.

2.4. Valuation method 2.4.1. Supply services value Food production. Breeding aquatic species and fishing provide food and sustain human life. These aquatic products include mainly fish, shellfish, shrimp, and algae. In this paper, we calculated the value of 67

Ocean and Coastal Management 161 (2018) 66–73

C. Sun et al.

climate regulation service is calculated by estimating a marine ecosystem's capacity to absorb carbon dioxide1 (Tang et al., 2012).

Table 1 The emergy transformities for calculating marine ecosystem service value. Item

Units

Transformity (sej/unit)

Marine fishing

J

2.00 × 106

Mariculture

J

2.00 × 106

Sea salt

g

1.00 × 109

Ocean power

J

8.00 × 10 4

N

g

4.19 × 109

P

1.78 × 10103.00 × 10 4

O2

g J g

CO2 a

g

2.32 × 108

Global emergy/dollar ratio Publications

＄ page

4.05 × 10123.39 × 1015

Wave energy

2.4.2.3. Waste treatment. Waste treatment refers to the physical, chemical, and biological purification processes through which waste water produced by humans, gas and solid waste from surface runoff, and direct emissions or atmospheric precipitation into the sea are converted into harmless substances (Shi et al., 2007). Oceans perform biological purification through the N and P elements that algae absorb through photosynthesis to reduce ocean eutrophication levels. We used the amounts of N and P absorbed as evaluation criteria, and the average absorption amounts of 1 t algae are 29.25 kg of N and 3.47 kg of P (Yue et al., 2014), multiplied by the emergy solar transformities of N and P respectively, after which the sum of the two emergies equates to the general waste treatment service value.

5.16 × 107

a The solar transformities of coal, oxygen and heat energy are respectively 1.0 × 109sej/ g , 5.16 × 107sej/ g and 6100sej/ J , so the emergy of producing (44/12)

2.4.2.4. Disturbance regulation. Concrete embodiments are constructed in the marine ecosystem to mitigate disturbances caused by various environmental fluctuations, such as the attenuation of effects of natural disasters such as storm tides and typhoons on marine marsh grass communities and mangrove forests (Zhang et al., 2007). The per unit area ocean disturbance regulation service value proposed by Costanza et al. (1997) was 8800 USD/km2 ·a , and Chinese scholar Han Weidong, using the expert evaluation method,2 found that every kilometer of mangrove coastline can provide about 80,000 USD worth of protection from typhoon disasters annually (Han et al., 2000). Fan (1995) concluded that the benefit of mangrove ecological maintenance functions on embankments could increase by 647000 yuan/km2 ·a . Zhao et al. (2007) estimated the value of regulating the disturbance of mangroves by the wave energy absorbed by it. Based on the latter's research conclusions, we aimed to evaluate the annual average wave energy absorbed by mangroves, which can be used to estimate the service value of regulating disturbances in the marine ecosystem.

g CO2 = (1.0 × 109sej/ g ) + (5.16 × 107sej/ g ) − 32.79KJ × 6100sej/ J ; therefore, = 8.51581 × 108sej the solar transformity of carbon dioxide is 2.32 × 108sej/ g (Lou et al., 2011).

food production service using the amount of aquaculture and ocean fishing as our raw data (Li et al., 2006; Cui and Zhao, 2004). Raw materials. Food, daily necessities, decorations, fuels, and drugs, as well as biological chemicals, are the primary raw materials produced from marine environments (Chen et al., 2006). However, traditional marine oil and gas resources and deposits accessed via placer are nonrenewable resources, so they are not included in the raw materials used to calculate marine ecosystem services. The raw materials that constitute marine ecosystem services include sea salt and ocean power: China has a coastline of more than 18,000 km, with abundant sunshine and sea salt resources, so we have used sea salt production as the criterion for evaluating the value of the sea salt supply, and each wind turbine is calculated as operating 12 h per day (Lai et al., 2013). Genetic resources. The value of marine ecosystem genetic resources is directly related to the number of marine species in the study area (Chen et al., 2006). De Groot. et al., 2002 estimated the value of the genetic resources of various global ecosystems at 6–112 USD ha −1year −1, and thereby formulated a widely adopted basis for calculating the value of genetic resources service (Li et al., 2011; Li and Tan, 2013). Lai et al. (2013), in the process of calculating the inshore marine services values for Guangxi's rich marine biological resources, used 80 percent of 112 USD ha −1year −1 as Guangxi's inshore marine genetic resources per unit area ecosystem service value. Combining Lai et al.’s work with findings from other research, we used 59 USD ha −1year−1, the median of De Groot's et al., 2002 assessment, as the per unit area of the value of genetic resources north of the Tropic of Cancer, and 80 percent of the highest value De Groot proposed, or 89.6 USD ha −1year −1, for the region south of the Tropic of Cancer (Guangdong, Guangxi, and Hainan) marine genetic resources per unit area ecosystem service value.

2.4.2.5. Biological control. The marine ecosystem plays a role in the biological regulation and control of some harmful organisms and diseases. The average value per unit area of marine ecosystem biological control service was estimated to be 38 USD ha −1year−1 (Costanza et al., 1997), and De Groot et al. (2002) proposed that the global biological control value of various ecosystems was 2–78 USD ha −1year−1. Because species' richness varies in different areas, we took the average of De Groot's median and the 38 USD ha −1year −1 proposed by Costanza, namely 39 USD ha −1year −1, as the Northern area's biological control per unit area ecosystem service value, and averaged De Groot's finding of 80 percent of the highest value and 38 USD ha −1year −1, or 50.2 USD ha −1year −1 as the per unit area ecosystem service value of marine biological control for the area south of the Tropic of Cancer (i.e., Guangdong, Guangxi, and Hainan). 2.4.3. Social services value MA (2005) defined cultural services as the nonmaterial benefits people obtain from ecosystem and divided it into cultural diversity, spiritual and religious values, knowledge systems, educational values, inspiration, aesthetic values, social relations, sense of place, cultural heritage values, recreation, and ecotourism. A substantial body of cultural services focuses on four points: aesthetics, cultural heritage, outdoor recreation, and spiritual significance (Daniel et al., 2012). Combining the domestic research of marine ecosystem services (Chen et al.,

2.4.2. Control services value 2.4.2.1. Gas regulation. Phytoplankton absorbs CO2 and releases O2 through photosynthesis, to balance CO2 and O2 . The equation of plant photosynthesis is:

6CO2 + 6H2 O → C6 H12 O6 + 6O2

(1)

Thus, 1.63 g carbon dioxide are needed and 1.19 g oxygen are released for every 1 g of dry matter. Based on previous studies' findings (Zhang et al., 2007; Tang et al., 2012), we used oxygen release quantities to calculate this value.

1 Calculating the mangrove photosynthesis process is complicated, because it is affected by many factors such as the salinisation of and the amount of light that permeates the environment, and thus any such data produced is of questionable quality. 2 The expert evaluation method is a qualitative evaluation method based on the Delphi method, and it utilizes the knowledge and experience of experts in the field to analyze and predict related issues. For further details on the expert evaluation method, see Liu et al. (2011).

2.4.2.2. Climate regulation. Marine ecosystems regulate climate by means of their function as a biological pump, through which carbon dioxide is absorbed to mitigate the effects of greenhouse gases (Shi et al., 2007). According to the photosynthesis equation, the value of 68

Ocean and Coastal Management 161 (2018) 66–73

C. Sun et al.

provinces and cities in the three regions. Y is the total marine ecosystem service values of 11 coastal provinces and cities, Yi is the marine ecosystem service value in the i region, and Yij is the marine ecosystem service value in the j coastal province in the i region. Finally, P is the total length of coastline in the 11 coastal provinces and cities, Pi is the length of coastline in the i region, and Pij is the coastline length of the j coastal province in the i region (Feng et al., 2015).

2006), we divided cultural services into tourism, scientific research, and recreation. 2.4.3.1. Recreation. The ocean provides visitors and local residents with sightseeing destinations and other functions. We used coastal provinces and cities' international tourism income to calculate the recreation services value (Wei et al., 2012). The recreation services of marine ecosystem tourism focus mainly on coastal zones and offshore waters, and therefore we used 60 percent of international tourism income to represent the leisure and entertainment provided by marine ecosystems (Zhang et al., 2010); 20 percent of international tourism income was used as the value of marine recreation service (Suo et al., 2011).

2.6. Information entropy The marine ecosystem services structure's information entropy comprehensively reflects dynamic changes and the degree to which development was balanced in different types of marine ecosystem services in the study area during a certain period. It therefore offers some guidance on optimizing and adjusting the structure of regional marine ecosystem services (Guo, 1994).

2.4.3.2. Scientific. The complexity and diversity of the marine ecosystem has fostered scientific research and contribution to human knowledge (Zhang et al., 2007). Costanza et al. (1997) estimated the scientific service value to be 62 USD ha −1year −1 per unit area; Zheng et al. (2012) interpreted the Jiaozhou Bay wetland ecosystem's scientific service value as the region's willingness to pay for a knowledge extension service and used that to estimate the value of the ecosystem knowledge expansion service. Zhao et al. (2007), in calculating the scientific value of China's mangrove forests, used the emergy analysis method and the number of published papers as an indicator of the value of scientific service. We used the number of papers averaging seven pages published by marine scientific research institutions as the benchmark for estimating the scientific service value of the marine ecosystem. Table 2 details the calculation parameters of each marine services.

N

H = − ∑ Pi ln Pi i=1

In this equation, Pi is the percentage of the different types of services values that account for the total value of a region, where N is the number of marine ecosystem service types in the region. When all the types of services values in the region are equal, P1 = P2 = …=PN = 1 N , and entropy H is the largest value, which indicates that the marine ecosystem services values in the study area have reached equilibrium. To better reveal the structural features of regional marine ecosystem services, the concept of equilibrium degree is introduced on the basis of Shannon information entropy (Zhao et al., 2004). N

J = − ∑ Pi ln Pi/ln N

2.5. Theil index

i=1

T = TWR + TBR =

∑ i

Yij

∑ i

⎛ Yij ⎞ ln ⎜⎛ Yi ⎟⎞ + P ⎝ Yi ⎠ ⎝ ij Pi ⎠

⎜

⎟

∑ i

Yi Y ⎛ i ⎞ ln ⎜⎛ Y ⎞⎟ ⎝ Y ⎠ ⎝ Pi P ⎠

(4)

The greater J is, the greater the equilibrium of all services values in the region. Compared to information entropy, the intuition and comparability of the degree of equilibrium is more obvious.

The Theil index can be used to measure differences within a region and between different regions, and therefore we applied the Theil index to further characterize regional differences in the values of marine ecosystem services in coastal regions.

Y ⎛ i⎞ ⎝Y ⎠

(3)

3. Results and discussion 3.1. Marine ecosystem services value

(2)

In Equation (2), TWR represents intra-region disparities, TBR represents inter-region disparities, and T represents the disparities of marine ecosystem services values in coastal China. i is for Northern, Central, and Southern, and i = 1,2,3, and j represents the number of coastal

We obtained the marine ecosystem services values for 11 coastal provinces and cities from 2005 to 2014; our results confirmed those of previous research, thus indicating that our expansion to other provinces was building on a firm foundation (see Appendix A).

Table 2 The emergy calculation process for marine ecosystem services value.

3.1.1. Marine ecosystem services value and its utilization type in coastal China From 2005 to 2014, the value of China's coastal marine ecosystem services showed a general upward trend. During the study period, the values of supply services, control services, and social services generally increased, but the proportion of supply services and control services fell in proportion to total ecosystem services, while the proportion of social services showed an upward trend. However, the value of China's coastal marine ecosystem services was mainly based on supply services, which in turn focused mainly on food supply (see Table 3 below for specific values).

Service

Specific

Item

Parameter

Supply services

Food production

food production

Raw materials

salt supply ocean power

Amount of aquaculture and ocean fishing Sea salt production Capacity of the wind power Sea area Algae yield, plant photosynthesis equation Algae yield, plant photosynthesis equation Algae yield

Control services

Genetic resources Gas regulation Climate regulation Waste treatment

Social services

Disturbance regulation Biological control Cultural Recreation Scientific service

oxygen release carbon dioxide absorption N, P elements absorption mangrove

3.1.2. The marine ecosystem services values in eleven coastal provinces and cities As can be seen in Table 4 below, the marine ecosystem services values of 11 coastal provinces and cities generally increased in the period between 2005 and 2014. According to the marine services values, 11 of the coastal provinces and cities can be divided into four groups. First, during the study period, the marine ecosystem services value in Hainan has always been the largest among the 11 coastal provinces and cities and showed an uptrend, increasing from 1.28e+23

Mangrove area Sea area International tourism income International tourism income Papers' pages

69

Ocean and Coastal Management 161 (2018) 66–73

C. Sun et al.

Table 3 The marine ecosystem services value of coastal China, 2005–2014. Years

2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

Marine ecosystem services value (× 1023sej )

5.24 5.38 5.27 5.57 5.79 5.87 6.20 6.42 6.42 6.61

Unit area service value (× 1017sej·km−2 )

1.58 1.62 1.59 1.68 1.74 1.77 1.87 1.93 1.93 1.99

Supply services

Control services

Social services

Value (× 1023sej )

%

Value (× 1022sej )

%

Value (× 1022sej )

%

3.79 3.83 3.56 3.78 3.93 3.78 3.96 4.02 4.09 4.24

72.4 71.1 67.5 67.9 67.9 64.4 63.9 62.6 63.7 64.2

8.62 8.61 8.59 8.61 8.61 8.62 8.62 8.63 8.64 8.65

16.4 16.0 16.3 15.4 14.9 14.7 13.9 13.4 13.5 13.1

5.84 6.95 8.52 9.31 9.96 12.3 13.8 15.38 14.66 15.03

11.2 12.9 16.2 16.7 17.2 20.9 22.2 24.0 22.8 22.7

distribution of regional disparities, this article summarizes the differences in China's coastal regions from 2005 to 2014, and the intra- and interregion differences in the Northern, Central, and Southern regions, based on the Theil index. These results are displayed in Table 5 below. As shown in Table 5, the disparities in China's coastal marine ecosystem services values generally narrowed from 0.218 to 0.168 between 2005 and 2014, for which intra-region disparities accounted for 80.94 percent of the differences in 2005, and only 18.73 percent of the differences in 2014 were due to inter-region differences. Both intra- and inter-region differences showed a narrowing trend, and intra-region disparities narrowed more rapidly, from 0.177 in 2005 to 0.03 in 2014, with an average annual narrowing of about 0.0147, while the variation of inter-regional differences was not obvious. During the study period, the total intra-region differences in the three economic zones decreased, but those differences in the Northern and Central regions showed a widening trend. Inter-region disparities reflect the differences between the Northern, Central, and Southern regions of China's coastal economic zone. The data shows that the inter-region differences in marine ecosystem services values from 2005 to 2014 decreased in volatility, with the exception of a brief increase later in the decade. This indicates that interregion differences in the coastal economic zones decreased as marine industries continued to develop. Intra-region disparities reflect the respective internal differences of the three economic zones along China's coast. Although the coastal provinces are contiguous and share similar

sej in 2005 to 1.31e+23 sej in 2014, but due to its larger basic value, this translated to an increase of only 1.95 percent. Second, the initial marine ecosystem services values in Guangdong and Shandong were high, even showing notable upward trends. By 2014, the marine ecosystem services values of these two provinces reached 1.28e + 23 sej and 1.11e + 23 sej increasing 48.38 and 37.49 percent, respectively, compared to 2005. Third, the initial marine ecosystem services values in Fujian, Zhejiang, and Liaoning were relatively moderate, and in the following decade were on a gradual upward trend. In both 2005 and 2014, the marine ecosystem services values of these three provinces were still in the middle position among the 11 coastal provinces and cities. Fourth, the initial values for Guangxi, Jiangsu, Shanghai, Hebei, and Tianjin were low. Although the growth rates in Jiangsu, Shanghai, and Tianjin were very large for coastal cities and provinces and even exceeded those in Fujian and Zhejiang, the marine ecosystem services values for these areas were very small to begin with, and by 2014 they were even lower and were classified accordingly (see Table 4 below). 3.2. Regional characteristics of China's coastal marine ecosystem services values Based on the three-level hierarchical structure—coastal China, the Northern, Central, and Southern economic zones, and the provinces—the disparities of values of marine ecosystem services were disaggregated into intra- and inter-region disparities. To better understand the pattern and Table 4 Marine ecosystem services values of 11 coastal provinces and cities in China. Unit: sej . Level

Area

2005

2006

2007

2008

2009

2010

2011

2012

2013

2014

First

Hainan

Second

Guangdong

1.28E+ 23 8.64E+ 22 8.05E+ 22 5.85E+ 22 5.13E+ 22 4.22E+ 22 2.78E+ 22 2.04E+ 22 1.33E+ 22 1.12E+ 22 4.18E+ 21

1.29E+ 23 9.13E+ 22 8.28E+ 22 5.87E+ 22 5.25E+ 22 4.26E+ 22 2.83E+ 22 2.23E+ 22 1.49E+ 22 1.03E+ 22 5.06E+ 21

1.27E+ 23 9.21E+ 22 8.26E+ 22 5.59E+ 22 4.91E+ 22 3.77E+ 22 2.59E+ 22 2.45E+ 22 1.71E+ 22 9.78E+ 21 5.39E+ 21

1.27E+ 23 9.33E+ 22 8.45E+ 22 5.84E+ 22 5.64E+ 22 4.78E+ 22 2.93E+ 22 2.61E+ 22 1.83E+ 22 9.97E+ 21 6.05E+ 21

1.28E+ 23 9.78E+ 22 9.02E+ 22 6.05E+ 22 5.62E+ 22 5.17E+ 22 3.15E+ 22 2.79E+ 22 1.75E+ 22 1.04E+ 22 6.49E+ 21

1.28E+ 23 1.06E+ 23 9.28E+ 22 6.15E+ 22 5.55E+ 22 4.37E+ 22 2.76E+ 22 3.18E+ 22 2.16E+ 22 1.08E+ 22 7.30E+ 21

1.29E+ 23 1.13E+ 23 9.96E+ 22 6.53E+ 22 5.95E+ 22 4.70E+ 22 2.87E+ 22 3.51E+ 22 2.35E+ 22 1.07E+ 22 8.20E+ 21

1.29E+ 23 1.20E+ 23 1.02E+ 23 6.89E+ 22 6.28E+ 22 5.06E+ 22 3.00E+ 22 3.79E+ 22 1.91E+ 22 1.10E+ 22 9.66E+ 21

1.30E+ 23 1.24E+ 23 1.01E+ 23 7.23E+ 22 6.42E+ 22 5.33E+ 22 3.14E+ 22 2.59E+ 22 1.82E+ 22 1.11E+ 22 1.10E+ 22

1.31E+ 23 1.28E+ 23 1.08E+ 23 7.64E+ 22 6.61E+ 22 4.87E+ 22 3.21E+ 22 2.83E+ 22 1.95E+ 22 1.18E+ 22 1.24E+ 22

Shandong Third

Fujian Zhejiang Liaoning

Fourth

Guangxi Jiangsu Shanghai Hebei Tianjin

70

Ocean and Coastal Management 161 (2018) 66–73

C. Sun et al.

Table 5 Intra- and inter-region disparities for marine ecosystem service values, 2005–2014. Years

Intra-region disparity

TWR

Northern

U4

U1

Central

U1/ U4

U2

0.177 0.174 0.186 0.167 0.159 0.171 0.164 0.149 0.131 0.137

0.009 0.010 0.014 0.008 0.008 0.015 0.015 0.015 0.016 0.022

U3

U2/ U4

% 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

Southern

%

5.09 5.69 7.55 4.87 5.08 8.50 9.32 10.24 11.87 16.16

0.026 0.029 0.038 0.035 0.035 0.048 0.051 0.044 0.028 0.032

T

TBR

0.142 0.135 0.134 0.124 0.116 0.108 0.098 0.090 0.087 0.083

TBR /T

%

%

80.94 80.95 82.21 83.17 81.60 84.45 85.50 83.95 78.83 81.27

19.06 19.05 17.79 16.83 18.40 15.55 14.50 16.05 21.17 18.73

U3/ U4 %

14.64 16.58 20.61 20.96 22.16 28.22 31.01 29.46 21.73 23.21

TWR /T

80.27 77.73 71.83 74.17 72.76 63.28 59.67 60.30 66.41 60.64

0.042 0.041 0.040 0.034 0.036 0.032 0.028 0.028 0.035 0.032

0.218 0.215 0.226 0.201 0.195 0.203 0.192 0.177 0.166 0.168

Note: TWR represents intra-region disparities, TBR represents inter-region disparities, and T represents the disparities of marine ecosystem services values in coastal China. Ui (i = 1,2,3) is a code name for the corresponding Theil index.

take a serious interest in the marine economy, the undeveloped areas gradually began to increase their investments in the marine economy, so the value of that sector increased while the regional marine economies that had been developed earlier grew more slowly. Therefore, the differences in coastal China's marine ecosystem services values subsequently decreased. From 2005 to 2014, the development of marine ecosystem services values in both intra- and inter-regions were unbalanced, as follows. First, the values of marine ecosystem services varied from region to region, so the inter-region disparities were large. Although there were only three provinces in the Southern region, its marine ecosystem services value was 2.42e + 23 sej, while the values in the North and Central regions were only 1.38e + 23 sej and 1.44e + 23 sej respectively. Second, although natural conditions were similar across the same region, as a result of cultural, social, and economic factors, the levels of services values in different provinces in the same economic zone were different, and the intra-region differences were also larger, such as the services values of Shandong and Liaoning in the North, which reached 8.05 e+22 sej and 4.22 e+22 sej respectively, while Tianjin's was only 4.18 e+21 sej.

resource endowments, the marine ecosystem services values in each nonetheless differ greatly due to the differences in cultural factors and levels of socio-economic development. During the study period, the total intra-region differences in the three economic zones decreased, but the intra-region differences in the Northern and Central regions grew larger. The main factor behind the decrease in the intra-region differences was the significant reduction of differences in the Southern region. We identified intra-region disparities as the main reason for the disparities between marine ecosystem services values in coastal China because, based on our calculations, the marine ecosystem services values of Hainan, Guangdong, Shandong, and Fujian, which are located in the Southern, Northern, and Central economic regions of China respectively, had the highest values of all the coastal provinces, reflecting a decrease in inter-regional differences and an increase in intra-regional differences. The reason the disparities between marine ecosystem services values in China's coastal areas showed a generally declining trend year over year was that some of the marine ecosystem services values are associated with physical geography, whose changes in values are not controlled by people. While the other component of the services value is closely correlated with the regional marine economy, the greater the extent to which marine industries develop, the higher the marine ecosystem services values are. Otherwise, the values of marine ecosystem services are low. Some areas had invested in marine industries prior to the beginning of this study, and therefore the values of their marine ecosystem services were higher than those in regions that had not yet developed their marine resources. As the rest of the region continued to

3.3. Structural changes to China's coastal marine ecosystem services 3.3.1. Temporal dimension analysis Changes to information entropy and the equilibrium degree of China's coastal marine ecosystem services structure were consistent and showed fluctuating uptrends. Information entropy increased from 1.5699 in 2005 to 1.6893 in 2014 and reached its highest point in 2011,

Table 6 The structure, information entropy, and equilibrium degree of marine ecosystem services in China's coastal areas, 2005–2014. Years

2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

Structure of marine ecosystem services (%) Food production

Raw materials

Genetic resources

Gas regulation

Climate regulation

Waste treatment

Disturbance regulation

Biological control

Cultural

Recreation

Scientific

44.97 44.51 40.07 41.82 41.67 38.3 37.73 37.98 39.15 39.17

6.26 5.97 6.39 6.15 7.07 7.23 8.23 7.31 7.3 8.23

21.17 20.6 21.05 19.9 19.16 18.89 17.9 17.29 17.27 16.78

0.02 0.02 0.01 0.02 0.02 0.02 0.02 0.02 0.02 0.02

0.11 0.11 0.08 0.09 0.1 0.1 0.1 0.11 0.11 0.12

0.05 0.05 0.04 0.05 0.05 0.05 0.05 0.05 0.05 0.06

4.05 3.94 4.03 3.8 3.66 3.61 3.42 3.3 3.3 3.21

12.22 11.89 12.15 11.48 11.06 10.9 10.33 9.97 9.97 9.68

8.35 9.67 12.11 12.5 12.89 15.66 16.65 17.95 17.1 17.03

2.78 3.22 4.04 4.17 4.3 5.22 5.55 5.98 5.7 5.68

0.02 0.02 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.04

71

H

J

1.5699 1.5858 1.6532 1.6362 1.6467 1.6928 1.7047 1.6971 1.6849 1.6893

0.6547 0.6613 0.6894 0.6823 0.6867 0.706 0.7109 0.7077 0.7027 0.7045

Ocean and Coastal Management 161 (2018) 66–73

C. Sun et al.

Table 7 Information entropy and the equilibrium degree of marine ecosystem services of 11 coastal cities and provinces, 2005–2014.

Tianjin Hebei Liaoning Shanghai Jiangsu Zhejiang Fujian Shandong Guangdong Guangxi Hainan

H J H J H J H J H J H J H J H J H J H J H J

2005

2006

2007

2008

2009

2010

2011

2012

2013

2014

1.2999 0.6680 1.0272 0.5279 1.0290 0.4469 0.9641 0.4955 1.4083 0.6116 1.1721 0.4888 0.9661 0.4029 1.0359 0.4499 1.6277 0.6788 1.3406 0.5591 1.0252 0.4275

1.2584 0.6467 1.0742 0.5520 1.0212 0.4435 0.9813 0.5043 1.3928 0.6049 1.2128 0.5058 0.9854 0.4110 1.0649 0.4625 1.6397 0.6838 1.3578 0.5662 1.0532 0.4392

1.2741 0.6547 1.1443 0.5881 1.1431 0.4964 0.9110 0.4682 1.3867 0.6022 1.3372 0.5577 1.1333 0.4726 1.1239 0.4881 1.6718 0.6972 1.4629 0.6101 1.0151 0.4233

1.2585 0.6467 1.1081 0.5695 1.0382 0.4509 0.9298 0.4778 1.3723 0.5960 1.2702 0.5297 1.1335 0.4727 1.1227 0.4876 1.6776 0.6996 1.3826 0.6005 1.0351 0.4317

1.2359 0.6351 1.1243 0.5778 1.0672 0.4635 0.9557 0.4911 1.4015 0.6086 1.2967 0.5408 1.1637 0.4853 1.1563 0.5022 1.6767 0.6993 1.3437 0.5836 1.0454 0.4360

1.2168 0.6253 1.1321 0.5818 1.2314 0.5348 0.7660 0.3937 1.4170 0.6154 1.3728 0.5725 1.1952 0.4984 1.1787 0.5119 1.6809 0.7010 1.4850 0.6449 1.0463 0.4363

1.1859 0.6094 1.1945 0.6139 1.2563 0.5456 1.0479 0.5385 1.3977 0.607 1.3752 0.5735 1.2419 0.5179 1.1954 0.5191 1.6792 0.7003 1.4955 0.6495 1.0579 0.4412

1.1391 0.5854 1.218 0.6259 1.2636 0.5488 0.8105 0.4165 1.3895 0.6035 1.3835 0.5769 1.2592 0.5251 1.2083 0.5247 1.6693 0.6961 1.5296 0.6643 1.0625 0.4431

1.1573 0.5948 1.2138 0.6238 1.2598 0.5471 0.8215 0.4222 1.3886 0.6031 1.3953 0.5819 1.2651 0.5276 1.1894 0.5166 1.6697 0.6963 1.5425 0.6699 1.0656 0.4444

1.1182 0.5747 1.1784 0.6056 1.1384 0.4944 0.8142 0.4184 1.4197 0.6166 1.4000 0.5838 1.2695 0.5294 1.1832 0.5139 1.6730 0.6977 1.5291 0.6641 1.0691 0.4458

we used the emergy analysis method to evaluate the marine ecosystem services values of China's coastal areas from 2005 to 2014. We found that the value of China's coastal marine ecosystem services generally presented a rising trend year over year during the study period, with Hainan, Guangdong, and Shandong dominating the marine ecosystem services values in China's coastal areas. The structure of marine ecosystem services in China's coastal areas was principally devoted to supply services. Disparities between the coastal provinces and cities in the value of China's coastal marine ecosystem services have generally narrowed, but the development of both intra- and inter-region marine ecosystem services values were unbalanced, and intra-region disparities were the main cause of disparities in the values of coastal China's marine ecosystem services. From 2005 to 2014, the structure of marine ecosystem services became more complex, and the proportions of various marine ecosystem services values developed in a balanced way. We integrated the values of various parameters of marine ecosystem services with emergy to ensure that our comparisons and analyses of marine ecosystem services values at different times and in different regions were as accurate as possible. China has about 3 million square kilometers under its jurisdiction, with abundant ocean resources and 5000 islands with areas greater than 500 m2. These areas are also extremely rich in sand, mineral, and species resources (Lou et al., 2005). However, due to this vast size, domestic and international research have to date failed to include a comprehensive and systematic analysis and evaluation of the value of the country's marine ecosystem services. Emergy analysis is a helpful method for assessing and comparing the values of marine ecosystem services in different areas using an integrated valuation framework; though the database developed in this paper was not exhaustive, it can serve as a basis for more studies to be added to it in the future. Furthermore, our research has also revealed the problems existing in the development of marine ecosystem services in China, such as the imbalance in the development of marine ecosystem service values between regions and the differences in the degree of development of various services, which is crucial to the future development of the ocean.

indicating that China's coastal marine ecosystem services structure was the most complicated and had the strongest equilibrium in 2011 (see Table 6 below). 3.3.2. Regional dimension analysis To further analyze the regional and chronological evolution of information entropy and equilibrium at different times and in different regions, we calculated and analyzed information entropy and the degree of equilibrium of the marine ecosystem services of 11 coastal provinces and cities from 2005 to 2014 (see Table 7 below). During the study period, the information entropy and the equilibrium degree of these areas generally increased, with only Tianjin and Shanghai showing a decline. This indicates that changes in the marine ecosystem services structure in various coastal provinces and cities were accelerating, that the types of marine ecosystem services were becoming more diverse, and that the proportion of marine ecosystem services values was becoming more balanced. In terms of geographical area, the ranking of information entropy for the 11 coastal provinces and cities remained basically unchanged during the study period, and the distribution of the degree of equilibrium was similar to the distribution of information entropy. Differences of information entropy and degree of equilibrium in the 11 coastal provinces and cities were relatively large, indicating that the developments of various marine ecosystem services values in these provinces were not balanced. Information entropy and the degree of equilibrium are reflective of the space and direction of improvements in marine ecosystem services values, and provinces and cities with smaller information entropy and degrees of equilibrium can combine their regional advantages, enrich the types of local marine ecosystem services, and learn from one another's experiences to further enhance the value of their marine ecosystem services. 4. Conclusions There are currently a number of initiatives designed to provide an accurate knowledge and understanding of the value of marine ecosystem services (Zhang et al., 2007; Sun et al., 2016). To aid this effort,

72

Ocean and Coastal Management 161 (2018) 66–73

C. Sun et al.

Appendix A Table A1 A comparison between our results and those of previous peer-reviewed studies.

Jiangsu Zhejiang Guangxi Coastal area

Results of this study (sej)

The equal value (108 yuan)

Results of previous studies (108yuan)

Previous studies

2.61417E+22 5.75714E+22 2.75995E+22 6.42E+23

438.9 966.6 463.4 9821.17

426.02 1157.11 652.28 2558.75

Xia et al. (2014) Jiang et al. (2014) Lai et al. (2013) Sun et al. (2016)

Li, H.X., Tan, C.L., 2013. Service function and value evaluation of marine ecosystem in Zhejiang province. Jiangsu Agric. Sci. 41 (4), 307–310. Li, Z.Y., Xu, S.J., Xu, H.Y., Cai, X., 2011. Value assessment of offshore marine ecosystem service in Guangdong province. Guangdong Agric. Sci. 23, 136–140. Liu, W.T., Gu, H., Li, H.C., 2011. Expert evaluation method based on delphi method. Comput. Eng. 37, 189–204. Lou, D., Gu, S.Z., Zhong, S.X., 2005. Current situation and development trend of marine industry in China. Resour. Sci. 27 (5), 20–26. Lou, B., Xu, Y., Lin, Z.G., 2011. Emergy analysis of coal-fired power generation system and construction of new emergy indices. Acta Ecol. Sin. 31 (24), 7591–7600. MA, 2005. Ecosystems and Human Well-being, Synthesis, Millennium Ecosystem Assessment. Island Press, Washington, D.C. Meillaud, F., Gay, J.B., Brown, M.T., 2005. Evaluation of a building using the emergy method. Sol. Energy 79, 204–212. Odum, H.T., 1996. Environmental Accounting-emergy and Environmental Decision Making. Wiley, New York, pp. 36–249. Odum, H.T., Odum, E.C., 1987. Ecology and Economy: Emergy Analysis and Public Policy in Texas. Policy Research Project Report. University of Texas, Austin. Shi, H.H., Zheng, W., Chen, S., Lv, J.B., Ding, D.W., 2007. Study on marine ecosystem service and its value assessment. Ecol. Environ. 3, 139–142. Souter, D.W., Linden, O., 2000. The health and future of coral reef systems. Ocean. Coast. Manag. 43, 657–688. Spalding, M.D., Ravilious, C., Green, E.P., 2001. United Nations Environment Programme, World Conservation Monitoring centre. World Atlas of Coral Reefs. University of California Press, Berkeley. State Oceanic Administration People’s Republic of China, 2006-2015. China Marine Statistical Yearbook. China Ocean Press. Sun, C.Z., Wang, S., Zou, W., 2016. Chinese marine ecosystem services value: regional and structural equilibrium analysis. Ocean Coast. Manag. 125 (2016), 70–83. Suo, A.N., Yu, Y.H., Miao, L.J., 2011. Assessment of ecosystem service value in the Bohai Sea. Mar. Econ. 1 (4), 42–47. Tang, C.W., Yang, S.S., Liu, L.J., Zhang, Z.M., Xiao, D.N., Tian, C.D., 2012. Ecological services value of forest ecosystem in eastern Qilian Mountains based on emergy theory. Chin. J. Ecol. 31 (2), 433–439. Wei, M., Feng, Y.J., Li, F., Zheng, Y.Q., 2012. Emergy analysis of tourism ecological system of Tai'an City. Acta Geogr. Sin. 67 (9), 1181–1189. Wilkinson, C.R., 2008. Status of the Coral Reefs of the World. Global Coral Reef Monitoring Network and Reef and Rainforest Research Centre, Townsville, Australia. Xia, T., Chen, S., Zhang, T., Wang, M., 2014. Valuation of ecosystem services in Jiangsu coastal waters. Acta Ecol. Sin. 34 (17), 5069–5076. Xu, C.C., Han, Z.L., 2003. Estimation framework of marine ecosystem services values. Ecol. Econ. 10, 199–202. Yue, D.D., Wang, L.M., Geng, R., Wang, Q., Dai, Y.Y., 2014. Initial assessment of seaweed farming ecological value in coastal waters in China. J. Agric. Sci. Technol. 16 (3), 126–133. Zhang, H., Kang, X., Wang, L., Fu, J., 2010. An assessment of offshore marine ecosystem value and services in Liaoning province. Resour. Sci. 32 (1), 177–183. Zhang, Y.G., Liu, Y., Li, C.P., Dong, L.J., 2003. The exploitation of marine oil and gas resources and the tactic countermeasures of petroleum in China. Geogr. Res. 22 (3), 297–304. Zhang, Z.H., Lv, J.B., Ding, D.W., 2007. Classification and quantification of marine ecosystem services. Coast. Eng. 26 (1), 57–63. Zhao, S., Hong, H.S., Zhang, L.P., Chen, W.Q., 2007. Emergy value of mangrove ecosystem services in China. Resour. Sci. 29 (1), 147–154. Zhao, J., Xu, J.H., Mei, A.X., Wu, J.P., Zhou, J.H., 2004. A study on the information entropy and fractal dimension of land use structure and form in Shanghai. Geogr. Res. 23 (2), 137–146. Zheng, W., Shi, H.H., 2009. Formation of marine ecosystem services and their contribution to human welfare. Ecol. Econ. 8, 178–180. Zheng, W., Shi, H.H., Xu, Z.J., Zhang, X.L., 2012. Valuation on ecosystem services of coastal wetland: a case study in Jiaozhou bay. Ecol. Econ. 1, 179–182.

References Beharry-Borg, N., Scarpa, R., 2010. Valuing quality changes in Caribbean coastal waters for heterogeneous beach visitors. Ecol. Econ. 69, 1124–1139. Brown, G., Hausner, V.H., 2017. An empirical analysis of cultural ecosystem values in coastal landscapes. Ocean&Coastal Manag. 142, 49–60. Brown, M.T., Ulgiati, S., 1997. Emergy-based indices and ratios to evaluate sustainability: monitoring economies and technology toward environmentally sound innovation. Ecol. Eng. 9, 51–69. Brown, M.T., Ulgiati, S., 2002. Emergy evaluations and environmental loading of electricity production systems. J. Clean. Prod. 10, 321–334. Bureau of Fisheries, Ministry of Agriculture, 2006-2015. China Fishery Statistics Yearbook. China Agriculture Press. Chen, S., Ren, D.C., Xia, T., Li, J.M., Du, G.Y., Wang, D., Wang, Q.X., Zhang, T., 2013. Marine ecological capital: valuation methods of marine ecosystem services. Acta Ecol. Sin. 33 (19), 6254–6263. Chen, S., Zhang, Z.H., Ma, Y., Shi, H.H., Ma, A.Q., Zheng, W., Wang, Q.X., Peng, Y.L., Lv, J., 2006. Program for service evaluation of marine ecosystems in China waters. Adv. Earth Sci. 21 (11), 1127–1133. Christie, M., Remoundou, K., Siwicka, E., Wainwright, W., 2015. Valuing marine and coastal ecosystem service benefits: case study of St Vincent and the Grenadines' proposed marine protected areas. Ecosyst. Serv. 11. https://doi.org/10.1016/j. ecoser.2014.10.002. Cinner, J.E., McClanahan, T.R., Graham, N.A.J., Daw, T.M., Maina, J., Stead, S.M., Wamukota, A., Brown, K., Bodin, O., 2012. Vulnerability of coastal communities to key impacts of climate change on coral reef fisheries. Glob. Environ. Change 22, 12–20. Coatanza, R., d'Arge, R., de Groot, R., Farber, S., Grasso, M., Hannon, B., Limburg, K., Naeem, S., O’neill, R.V., Parurlo, J., Raskin, R.G., Sutton, P., van den Belt, M., 1997. The value of the world's ecosystem services and natural capital. Nature 387, 253–260. Cui, L.J., Zhao, X.S., 2004. Researches on the emergy analysis of Poyanghu wetland. Acta Ecol. Sin. 24 (7), 1480–1485. Daily, G.C., 1997. In: Daily, G.C. (Ed.), Nature's Service: Societal Dependence on Natural Ecosystems. Island Press, Washington DC. Daniel, T.C., Muhar, A., Arnberger, A., Aznar, O., Boyd, J.W., Chan, K.M.A., Coatanza, R., Elmqvist, T., Flint, C.G., Gobster, P.H., Gret-Regamey, A., Lave, R., Muhar, S., Penker, M., Ribe, R.G., Schauppenlehner, T., Sikor, T., Soloviy, I., Spierenburg, M., Taczanowska, K., Tam, J., Dunk, A.V.D., 2012. Contributions of cultural services to the ecosystem services agenda. Proc. Natl. Acad. Sci. 109 (23), 8812–8819. De Groot, R.S., Wilson, M.A., Boumans, R.M.J., 2002. A typology for the classification, description and valuation of ecosystem functions, goods and services. Ecol. Econ. 41, 393–408. Fan, H.Q., 1995. An ecological pattern of sea dyke maintenance by mangroves and assessment of its benefits along Guangxi Coast. Guangxi Sci. 2 (4), 48–52. Feng, C.C., Zeng, Z.R., Cui, N.N., 2015. The economic disparities and their spatio-temporal evolution in China since 2000. Geogr. Res. 34 (2), 234–246. General Administration of quality supervision, inspection and Quarantine of the people’s Republic of China, Administration of the people’s Republic of China, 2011. Technical Directives for Marine Ecological Capital Assessment. Guo, X.G., 1994. Entropy method and its application in comprehensive evaluation. Finance Trade Res. 6, 56–60. Han, W.D., Gao, X.M., Lu, C.Y., Lin, P., 2000. The ecological values of mangrove ecosystems in China. Ecol. Sci. 19 (1), 40–46. Jiang, K.Y., Wang, B., Yang, X.S., Wu, M., 2014. Valuation of ecosystem services of coastal wetlands in Zhejiang province. Zhejiang For. 30–33 S(1). Lai, J.X., Jiang, F.J., Xu, M.B., Chen, M., Li, Y.C., Chen, B., 2013. Value assessment of offshore marine ecosystem service in Guangxi. J. Guangxi Acad. Sci. 29 (4), 252–258. Lan, S.F., Qin, P., Lu, H.F., 2002. Emergy Synthesis of Ecological-economic Systems. Chemical Press, Beijing, pp. 75–324. Li, J.P., Chen, F.P., Wang, Z.S., 2006. The emergy synthesis and sustainability analysis of city's environment and economy. Acta Ecol. Sin. 26 (2), 439–448.

73