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Journal of Geographical Sciences >

2021 , Vol. 31 >Issue 9: 1245 - 1260

DOI: https://doi.org/10.1007/s11442-021-1896-y

Research Articles

Evaluating changes in ecological land and effect of protecting important ecological spaces in China

  • GAO Jixi , 1 ,
  • LIU Xiaoman , 1, * ,
  • WANG Chao 1 ,
  • WANG Yong 2 ,
  • FU Zhuo 1 ,
  • HOU Peng 1 ,
  • LYU Na 1
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  • 1. Ministry of Ecology and Environment Center for Satellite Application on Ecology and Environment, Beijing 100094, China
  • 2. State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China
* Liu Xiaoman (1979-), PhD and Professor, specialized in ecological protection and restoration. E-mail:

Gao Jixi (1964-), PhD and Professor, specialized in regional ecological protection and restoration. E-mail:

Received date: 2020-11-30

  Accepted date: 2021-07-10

  Online published: 2021-11-25

Supported by

National Key Research and Development Program of China(2017YFC0506506)

National Key Research and Development Program of China(2016YFC0500206)

Copyright

Copyright reserved © 2021. Office of Journal of Geographical Sciences All articles published represent the opinions of the authors, and do not reflect the official policy of the Chinese Medical Association or the Editorial Board, unless this is clearly specified.
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Abstract

It is important to quantitatively analyze the effects of protection of important ecological spaces in China to ensure national ecological security. By considering changes in the ecological land, this study examines the effects of protecting three types of important natural ecological spaces in China from 1980 to 2018. Moreover, considering important ecological spaces and their surroundings yields differences in the effects of protection between internal and external spaces, where this can provide a scientific basis for the categorization and zoning of China’s land. The results show the following: (1) In 2018, the ratio of ecological land to important natural ecological spaces accounted for 92.64%. This land had a good ecological background that reflects the developmental orientation of important ecological spaces. (2) From 1980 to 2018, the area of ecological land in important ecological spaces shrank but the rate of reduction was lower than the national average, which shows the positive effect of regulating construction in natural ecological spaces. The restorative effects of ecological projects to convert farmland into forests and grasslands have been prominent. The expanded ecological land is mainly distributed in areas where such projects have been implemented, and the reduced area is concentrated in grain-producing areas of the Northeast China Plain and agricultural oases of Xinjiang. In the future, the government should focus on strengthening the management and control of these areas. (3) The area ratio of ecological land was the highest in national nature reserves. The rate of reduction in its area was the lowest and the trend of reduction was the smallest in national nature reserves, which reflects differences in the status of ecological protection among different spaces. (4) The ratio of ecological land to important ecological spaces was higher than that in the surrounding external space, and the rate of reduction in it was lower. Thus, the effects of internal and external protection had clear differences in terms of gradient.

Key words： ecological spaces; ecological land; spatial and temporal dynamic changes; protection effect; categorized and zoned governance

Cite this article

GAO Jixi , LIU Xiaoman , WANG Chao , WANG Yong , FU Zhuo , HOU Peng , LYU Na . Evaluating changes in ecological land and effect of protecting important ecological spaces in China[J]. Journal of Geographical Sciences, 2021 , 31(9) : 1245 -1260 . DOI: 10.1007/s11442-021-1896-y

1 Introduction

China’s protection of its eco-environment has entered the new stage of focusing on the “source” control of the spatial pattern of the country. The construction of an ecological spatial pattern has led to the emergence of an important part of controlling this development (Gao et al., 2020). An ecological space refers to national land with attributes that are conducive to providing ecological products or services, where this is the material basis of human survival and development (Qi et al., 2016). It can help provide support for ecological protection and socioeconomic development (Gao et al., 2020). From the perspectives of maintaining important ecological functions, biodiversity, and nature conservations, such areas are the most important ecological spaces in China. Nature conversations are established to maintain the health and stability of natural ecosystems (GOCPC et al., 2019; Tang et al., 2019), which are the critical ecological spaces in China (SCPRC, 2010). Key ecological areas are important for enhancing national ecological services and ensuring national ecological security. Biodiverse conservation areas are critical for protecting biodiversity (MEP et al., 2011). These three types of ecological spaces play an important role in ensuring China’s ecological security (Hou et al., 2013).
With accelerated industrialization and urbanization in recent decades, a series of problems, such as ecological destruction, environmental pollution, and the disorderly development of national land, have emerged and become increasingly prominent. Rapid human activities continue to encroach on ecological spaces and degrade their ecological functions. Important ecological spaces have gradually lost their natural attributes, affecting the sustainable development of China’s eco-environment. It is thus important to analyze the effectiveness of the country’s plans for ecological protection. Some researchers have portrayed the effectiveness of conservation from the perspective of the objects to be protected. Joppa et al. (2011) assessed the effectiveness of conservation of 359 nature reserves worldwide with the aim of ensuring the diversity of species. Willcock et al. (2016) assessed the effectiveness of controlling African biodiversity. Other scholars have focused on the effectiveness of conservation of ecosystems. Songer et al. (2009) comparatively assessed the effectiveness of conservation of forest ecosystems in the Chatthin Wildlife Sanctuary in Myanmar, and Wang et al. (2018) conducted a comparative analysis of forest conservation in the Hainan Nature Reserve of China. Some researchers have also examined the effectiveness of conservation from the perspective of converted land cover. Nagendra (2008) assessed land cover changes in 49 nature reserves in 22 countries, and Fan et al. (2012) studied the intensity of conversion of land cover in 180 national nature reserves in China from the late 1980s to 2005. Zhao et al. (2014) analyzed the disturbance caused by land use changes in key areas on the conservation of biodiversity. Some studies have used ecological parameters, ecological quality, and ecological functions as indicators to study the effectiveness of conservation. Xu et al. (2019) assessed changes in the quality of the eco-environment of key ecological areas in China, and Huang et al. (2015) analyzed the types of forest for conserving water supply, water and soil conservation, wind belt and sand stabilization, and biodiversity with the aim of maintaining ecological areas. Peng et al. (2018) explored the effectiveness of conservation of key ecological areas by using ecosystem patterns, vegetation growth, and service functions as core elements. Some work has employed the biotope to explore the effectiveness of conservation of typical nature reserves in China (Zhu et al., 2018). The above studies provide methodologies and indicators for assessing the effectiveness of conserving important ecological spaces in China. However, they have some problems that need to be urgently solved: (1) The current research has focused on nature reserves as important ecological spaces, and work on key ecological function zones and biodiversity priority areas, which are two important ecological spaces unique to China, is relatively scarce. (2) An overall assessment of the effectiveness of conservation of the three types of important ecological spaces in China at the national level is lacking. (3) The results of ecological evaluation and assessment of the management of specific pieces of land are difficult to be directly used in practice.
Based on land management practices in China, this paper uses ecological land as the point of entry to assess the effectiveness of protection of the three most important ecological spaces at the national level: nature reserves, key ecological function zones, and biodiversity priority areas. Ecological land is basic resource for human survival that provides essential ecological services for human beings as well as such functions as soil and water conservation, shelter belt and wind break, sand stabilization, climate regulation, and environmental purification (Qu et al., 2019). It plays a special role in maintaining the ecological balance, ensuring the ecological security of the country, and helping cope with global climate change (Guan et al., 2018). It is a “barometer” of the eco-environmental quality of a country or a region, and an important indicator of the effectiveness of protection of important ecological spaces in China (Yu et al., 2015). On the one hand, this study examines the effectiveness of protection of three types of important ecological spaces from 1980 to 2018 from a temporal perspective. On the other hand, it considers important ecological spaces and their surrounding regions as a whole to identify differences in the effectiveness of the synergistic internal and external protection of the three types of important ecological spaces based on the difference in gradient between them. The purpose is to provide a new perspective and method for assessing the effectiveness of China’s ecological space, and a scientific basis for the classification and zoning control of its land space.

2 Data and methodology

2.1 Data

2.1.1 Boundary data
By the end of 2019, there were 474 na- tional nature reserves (Ma et al., 2019), 25 key ecological function zones (SCPRC, 2010), and 32 terrestrial biodiversity priority areas in China (MEP et al., 2011) (Figure 1). The boundaries of the key ecological function zones were derived from the Main Functional Area Planning issued by the State Council in 2010 (SCPRC, 2010), those of biodiversity priority areas were derived from the China Biodiversity Conservation Strategy and Action Plan (2011-2030) issued by the former Ministry of Environment Protection in 2010 (MEP et al., 2011), and the boundaries of national-level nature reserves were taken from the Nanjing Institute of Environmental Science, the Ministry of Ecology and Environment.
Figure 1 Distribution map of three types of natural ecological spaces in China
2.1.2 Land use data
The Institute of Geographic Sciences and Natural Resources Research built a national-scale land use database for China using satellite data as the main source of information. This database has multiple phases of 100 m×100 m raster data, and the classification accuracy of each land use type exceeds 90% (Liu, 1996; Liu et al., 2003; Liu et al., 2010; Zhang et al., 2012; Liu et al., 2014; Liu et al., 2016; Liu et al., 2018). Each phase of land use data includes six primary types of agricultural land, forest land, grassland, water bodies, urban and rural industrial land for mining, and unused land as well as 25 secondary types of paddy fields, dry land, and forested land. We used five national 100 m×100 m land use datasets from this database for 1980, 1990, 2000, 2010, and 2018.

2.2 Methodology

2.2.1 Division of ecological land
“Ecological land classification” has long been a popular topic in academic research. Research on the subject has been carried out from various perspectives and different classification schemes have been proposed (Tang et al., 2011; Yang et al., 2011; Long et al., 2015; Peng et al., 2015; Qu et al., 2015; Li et al., 2016; Zhou et al., 2016; Liu et al., 2017; Wang et al., 2017; Wen et al., 2017; An, 2018; Xie et al., 2018). Four views in the area are considered mainstream. The first is “ecological element determinism,” which defines ecological land from the perspective of spatial morphology. It considers the spatial positioning of ecological elements as ecological land, and divides it into two categories according to spatial patterns: surface ecological land, such as mature forests, lakes, water bodies, wetlands, agricultural land, and open spaces; and linear ecological land, such as rivers and coastal mudflats (Yu et al., 2015). The second major view in ecological land classification is “pan-ecological functional determinism,” which defines ecological land from the perspective of its ecological functions, and claims that any land that can provide ecosystem services can be considered ecological land. Ecological land thus includes agricultural land, woodland, grassland, marshes, ground without artificial pavement, and ground with permeable water (Zhang et al., 2004; Deng et al., 2009; Han et al., 2010). The third view is "subject function determinism,” which classifies ecological land by subject function. This view considers ecosystems that perform predominantly natural ecological functions, and are important for the maintenance of key ecological processes as ecological lands providing important ecosystem services and possessing high ecological sensitivity (Zhou et al., 2006; Yu et al., 2009; Fei et al., 2019). The fourth view is “utilization form determinism,” which classifies ecological land from the perspective of whether it is exploited. This view considers land, other than agricultural and construction land, which is not used by humans, and can perform ecological functions directly or indirectly as ecological land (Xu et al., 2007; Zhao et al., 2009). In the author’s opinion, ecological land should be classified according to the basic criterion of not being exploited by human beings as well as its main ecological functions. According to this criterion, ecological land can be divided into two types.
First, woodlands, grasslands, and wetlands (including water bodies) can provide ecological services, such as ecological regulation and biological support, directly or indirectly. Such ecological lands play an important role in improving the environment, providing environmental regulation, maintaining biodiversity and regional ecological balance, and providing ecological products. At the same time, they have some self-regulation, restoration, and maintenance capabilities of their own. Second, such land types as sandy land, the Gobi desert, saline land, marshland, bare land, and bare rocky land are not directly used by human beings, but are used for ecological restoration and protection. They play an important role in ecological balance as well as the Earth’s native environment. The ecological functions of such lands are more fragile, and excessive human intervention can have serious negative impacts on ecological security. Such land should thus be protected (Yu et al., 2009; Fei et al., 2019). Ecological land thus includes four primary categories—wetland, forest land, grassland, and other unused land—and 19 secondary categories. All land that has been exploited by human beings is considered non-ecological, including areas with the main functions of providing agricultural production and living spaces for urban residents (Table 1).
Table 1 Correspondence among non-ecological land, ecological land and different land use types
Land type Corresponding land use types
Ecological land Woodland, shrubland, open woodland and other woodland
High-coverage grassland, medium-coverage grassland, low-coverage grassland
Canals, lakes, reservoirs, ponds, permanent glaciers and snowfields, beaches, mud flat
Sandy land, Gobi, saline land, marsh land, bare land, bare rocky land
Non-ecological land Agricultural land Paddy field, dry land
Urban land Urban and rural residential areas, other construction land
2.2.2 Expressions for expansion, reduction, and maintenance of ecological land
Based on national land use data in 1980 and 2018, the expansion, reduction, and maintenance of ecological land, in the context of the three types of important ecological spaces, are studied to reflect the changing characteristics of ecological land in important ecological spaces in terms of patterns. The area of ecological land is expressed as “S” because of the complex land use types in the study area, and the fragmented distribution of ecological and non-ecological land. The ecological area in 1980 is denoted by S1 and that in 2018 by S2 within the same area.
When S1<S2, it means that the area of ecological land in the region has increased. This means that non-ecological land was converted into ecological land, and the change is expressed as an “expansion.”
When S1>S2, it means that the area of ecological land in the region has decreased. This means that the ecological land was converted into non-ecological land, and the change is expressed as a “reduction.”
When S1=S2, it means that the area of ecological land in the region has remained unchanged. This means that ecological land was not transformed, and the change is expressed as “maintenance.”

3 Results and analysis

3.1 Analysis of important ecological spaces in 2018

3.1.1 Analysis of the state of ecological land in 2018
In 2018, the total area of ecological land within important ecological spaces in China was 6,953,739.38 km2, accounting for 92.64% of the total area of national nature reserves, and the area of non-ecological land was 552,747.24 km2, accounting for 7.36% (Table 2). A total of 93.65% of biodiversity priority areas, 90.6% of key ecological function zones, and 97.68% of the national nature reserves were classified as ecological land. The important ecological space in China was thus dominated by ecological land. National-level nature reserves, key ecological function zones, and biodiversity priority areas form the core of ecological spaces in China, and have a good ecological background. They occupy an important position in national ecological protection efforts and help maintain national ecological security. The ratio of the area of ecological land followed the pattern of national nature reserves > biodiversity priority areas > key ecological function zones. As the first to be established and the most strictly protected ecological spaces in China, national nature reserves have the highest ratio of the area of ecological land, where this reflects the difference in gradient of the effectiveness of the ecological protection of important ecological spaces.
Table 2 The area and ratio of different lands in three important natural ecological spaces in 2018 (km2, %)
Important ecological spaces Area and proportion of
non-ecological land		 Area and proportion of
ecological land		 Total
National nature reserves 22631.59 (2.32) 951925.26 (97.68) 974556.85
Biodiversity priority areas 175290.14 (6.35) 2583678.34 (93.65) 2758968.48
Key ecological function zones 354825.50 (9.40) 3418135.78 (90.60) 3772961.29
Three types of important ecological spaces (Total) 552747.24 (7.36) 6953739.38 (92.64) 7506486.62

Note: The content in brackets is area percentage

3.1.2 Analysis of pattern distribution of ecological land
In general, the ecological land in the three important ecological spaces was mainly distributed to the northwest of the Hu Huangyong Line, where national nature reserves were mainly distributed in Xinjiang, Qinghai, Tibet, and Yunnan (Figure 2a). The percentage of ecological land within the key ecological function zones was relatively high, and included the Qiangtang Plateau Desert in the northwest Tibetan Plateau, Altun Grassland Desertification Control, Sanjiangyuan Grassland Meadow Wetland, Zoige Grassland Wetland, Southeast Tibetan Plateau Marginal Forest, Hulun Buir Steppe Meadow, Sichuan and Yunnan Forest and Biodiversity, Altay Mountain Forest and Grassland, and Tarim River Desertification Control (Figure 2b). The percentage of ecological land within biodiversity priority areas was also relatively high, including Kumtag, Tianshan Junggar Basin, Qilian Mountains, Qiangtang Sanjiangyuan, southeast Himalayan source, Da and Xiao Hinggan Mountains in northeast China, Hulun Buir, Xilin Gol Grassland, and Altay Mountains (Figure 2c).
Figure 2 Distribution of different kinds of lands in three important natural ecological spaces of China in 2018 (a. national nature reserves; b. key ecological function zones; c. biodiversity priority areas)

3.2 Analysis of changes in ecological land and effectiveness of conservation of important ecological spaces in 1980-2018

3.2.1 Analysis of characteristics of overall change and effectiveness of conservation of ecological land
From 1980 to 2018, the area of ecological land within important ecological space sho- wed a gradual decrease of 77,187.6 km2 at a rate of 1.1%, lower than the rate of decrease of 1.66% in the country’s ecological land area. The area of non-ecological land continued to increase, with an increase of 77,187.6 km2 at a rate of 16.23% (Figure 3). Of this, the area of urban land increased by 12,671.64 km2 at a rate of 66.75%, and that of agricultural land increased by 64,515.96 km2 at a rate of 14.13%. This indicates that China’s urbanization has advanced rapidly, and construction-related and agricultural activities have become increasingly evident with rapid socioeconomic development since 1980. This has led to continual encroachments on ecological land within important ecological spaces, which have exhibited a clear trend of contraction. However, in general, the rate of reduction in ecological land in important ecological spaces is lower than the national average, which reflects the positive effects of ecological protection.
According to the different periods of mo- nitoring, ecological land in 1980, 1990, 2000, 2010, and 2018 occupied 7,030,926.98 km2, 7,023,635.84 km2, 6,996,910.94 km2, 6,992, 669.46 km2, and 6,953,739.38 km2, respec- tively (Figure 3). The area of ecological land decreased by 7291.14 km2, 26,724.91 km2, 4241.47 km2, and 38,930.08 km2 in 1980- 1990, 1990-2000, 2000-2010, and 2010- 2018, respectively, with annual reductions of 0.01%, 0.04%, 0.006%, and 0.07%. The reduction from 2000 to 2010 was the lowest, mainly because China launched a series of ecological protection projects in 1999. The areas occupied by forests and grasslands increased significantly in this period. This reflects the restorative effects of ecological protection projects. An important reason for the highest annual reduction in ecological areas from 2010 to 2018 is the reduction in the scale and scope of national ecological protection projects, which focused on supplementation and consolidation. The effects of ecological protection following the promulgation of the Main Functional Area Planning and the China Biological Diversity Protection Strategy and Action Plan (2011-2030) have not yet been fully realized.
Figure 3 The area variation of different kinds of lands in important natural ecological spaces in China from 1980 to 2018
3.2.2 Analysis of characteristics of ecological land transfer and effectiveness of conservation
From 1980 to 2018, 192,739.59 km2 of ecological land were converted into non-ecological land within important ecological spaces, and 115,551.99 km2 of non-ecological land were converted into ecological land (Table 3). The overall reduction in the area of ecological land was 77187.6 km2. Of this, 94.2% was occupied by agricultural development, and 5.8% by urban settlements. A total of 95.29% of the ecological land in national nature reserves, 92.76% in biodiversity priority areas, and 94.84% in key ecological function zones had been occupied by agricultural development activities. A total of 96.9% of the increased area of ecological land occurred through the conversion of agricultural land. On the contrary, agricultural construction activities continued to encroach on and destroy ecological land.
Table 3 Area transfer of different lands in three important natural ecological spaces from 1980 to 2018 (km2)
Important ecological
spaces		 1980 2018
Ecological land Non-ecological land
Agricultural land Urban land
National nature
reserves
Ecological land 947542.01 9781.70 483.03
Non-ecological land Agricultural land 3777.17 11505.56 304.24
Urban land 606.08 197.91 359.15
Biodiversity priority areas
Ecological land 2540382.94 57294.11 4470.45
Non-ecological land Agricultural land 42325.72 105758.69 3239.70
Urban land 969.69 1232.51 3294.68
Key ecological function zones
Ecological land 3350262.44 114485.76 6224.55
Non-ecological land Agricultural land 65872.51 217470.71 6320.22
Urban land 2000.84 3363.53 6960.74
Three types of
important ecological
spaces (Total)
Ecological land 6838187.39 181561.56 11178.03
Non-ecological land Agricultural land 111975.40 334734.96 9864.15
Urban land 3576.60 4793.95 10614.58
3.2.3 Analysis of characteristics of change in ecological land and effectiveness of conservation of important ecological spaces
From 1980 to 2018, the area of ecological land occupied by the three important ecological spaces showed a decreasing trend. A linear relationship (y=ax+b) was fitted between the area of ecological land and time, with “a” indicating the trend of its slope and R2 indicating the degree of fit. A higher degree of fit was achieved when R2 was closer to 1. The results show that the slope of the area of ecological land occupied by national nature reserves was -0.134 and R2=0.942, with the least prominent trend of reduction. The slope of the trend of reduction in the area occupied by biodiversity priority area was -0.452 with R2=0.849, and the slope of change in the area occupied by key ecological function zones was -1.265 with R2=0.939. It showed the most prominent trend of reduction of the three areas (Figure 4). The rates of reduction of the key ecological function zones, biodiversity priority areas, and national nature reserves were 1.52%, 0.71%, and 0.61%, respectively. This shows the differences in the effectiveness of conser- vation for the three types of natural ecological spaces. National-level nature reserves, as an important ecological space that is guaranteed the most stringent protections in China, exhibited the smallest reduction in area since 1980. The area of ecological land, in terms of the area and annual rate of reduction, changed by the least in 2000-2010 and by the most in 2010-2018 (Figure 5).
Figure 4 Charts showing the changing trend of ecological land in important natural ecological spaces in China from 1980 to 2018 (a. national nature reserves; b. key ecological function zones; c. biodiversity priority areas)
Figure 5 Reduced area and annual reduction rate of ecological land in the three important natural ecological spaces in different monitoring periods from 1980 to 2018 (a. reduced area of ecological land; b. annual reduction rate of ecological land)
3.2.4 Analysis of changes in ecological pattern and effectiveness of conservation
By calculating the expansion, reduction, and maintenance of ecological land for the three types of important ecological spaces, we found that 98.9% of the area of ecological land occup- ied by national nature reserves, 97.6% occupied by biodiversity priority areas, and 96.5% by key ecological function zones remained unchanged from 1980 to 2018 (Table 4). In general, important ecological spaces in China have been stable in terms of area since 1980, with the most stability exhibited by national nature reserves, followed by biodiversity priority areas and key ecological function zones. The reduction in the areas of national-level nature reserves, biodiversity priority areas, and key ecological function zones accounted for 1.1%, 2.4%, and 3.5%, respectively, while the expansions in their areas accounted for 0.5%, 1.7%, and 2%, respectively. The ratio of reduction in ecological land was thus larger than that of its expansion, and the overall effect of protection was good.
Table 4 Area variation and ratio of ecological land in important natural ecological spaces from 1980 to 2018 (km2)
Changes National nature reserves Biodiversity priority areas Key ecological function zones
Area Percentage (%) Area Percentage (%) Area Percentage (%)
Unchanged 947542.01 98.9 2540382.94 97.6 3350262.44 96.5
Reduced 10264.73 1.1 61764.55 2.4 120710.31 3.5
Expanded 4383.25 0.5 43295.40 1.7 67873.34 2.0
The spatial pattern shows that areas where ecological space expanded included the Loess Plateau, parts of hilly areas in southern China, where farmland had been converted into forests and grasslands. This is closely related to the policy of converting farmland into forest lands, grasslands and wetlands, which has had a significant impact on changes in important ecological spaces. The shrinking areas were concentrated in important grain-producing areas of the Northeast China Plain as well as the oases farming area of Xinjiang. The ecological land in these areas was mainly encroached by large-scale agricultural development, and control over this should be strengthened in the future.
The shrinkage of nature reserves was prominent in the Raohe black bee, Naoli River, Uygur River, Wudalianchi and Tumuji in Northeast China as well as coastal Binzhou shell dikes and wetlands, and Yancheng rare bird wetlands. The expansion of reserves was evident in Huihe River, Nanweng River, and Xilin Gol Grassland (Figure 6a). The shrinkage of ecological land was prominent in the grain-producing area in the northeast of the Sanjiang Plain wetlands, Da and Xiao Hinggan Mountain forests, and the predominantly interlocking farming-pastoral zones in the Horqin Grassland. Ecological land also shrank in the Tarim River Desertification Control ecological function zones in Northwest China. The area is also home to a modern agricultural demonstration park, where agricultural development is gradually crowded out of ecological space. The expanded area of ecological land was mainly distributed in key ecological function zones of the Hilly Gully Soil and Water Conservation Area on the Loess Plateau, Qinba (Qinling-Daba Mountains) Biodiversity Area, and Dabie Mountain Soil and Water Conservation Area (Figure 6b). The reduced ecological land in biodiversity priority areas was mainly distributed in the Sanjiang Plain and the Songnen Plain, where agricultural production was the main focus, the Northwest Ningxia Plain where irrigated agriculture was the focus, West Ordos-Helanshan-Yinshan Mountains where oasis agriculture was underway, and the Tarim River Basin biodiversity priority areas. The expansion in ecological land was evident in such biodiversity priority areas as Ziwuling Ridge of the Liupan Mountains, the Wuling Mountains, and the Qinling Mountains, where farmlands were converted into forests and grasslands (Figure 6c).
Figure 6 Maps showing ecological land in three important natural ecological spaces in China from 1980 to 2018 (a. national nature reserves; b. key ecological function zones; c. biodiversity priority areas)

3.3 Analysis of status and effectiveness of ecological land conservation inside and outside of important ecological spaces

In 2018, the ratios of the area of ecological land in important ecological space (inside), external 0-5 km (outside) area and external 5-10 km (outside) area were 92.64%, 81.17% and 77.44%, respectively. The ratios of the area of ecological land were 11.47 and 15.2 percentage points higher than those of the external 0-5 km area and the external 5-10 km area, respectively. The areas of ecological land in biodiversity priority areas, external 0-5 km areas, and external 5-10 km areas were 93.65%, 76.62%, and 73.41%, respectively. The ratios of key ecological function zones, external 0-5 km, and external 5-10 km areas were 90.6%, 83.96%, and 77.59%, respectively. The ratios of national-level nature reserves, external 0-5 km areas, and external 5-10 km areas were 97.68%, 83.94%, and 81.05%, respectively (Figure 7). The proportions of the area of biodiversity priority areas, key ecological function zones, and national nature reserves were higher than those of the surrounding areas. In 2018, the effectiveness of protection of important ecological space in China was higher than that of the surrounding external areas. Thus, the further away from an important ecological space an area was, the smaller its ratio of ecological land, and the worse its ecological protection status. This quantitatively reflects the significance and importance of the construction of important ecological spaces in China.
Figure 7 Area ratio of different lands inside and outside three important natural ecological spaces in China
From 1980 to 2018, the areas of ecological land in important ecological spaces, external 0-5 km, and external 5-10 km areas decreased by 1.1%, 1.99% and 2.15%, respectively. In terms of separation, the reduction rates in area were 0.71%, 2.71%, and 3.12% for biodiversity priority areas, external 0-5 km, and external 5-10 km areas, respectively; 1.52%, 1.6%, and 1.55% for key ecological function zones, external 0-5 km areas, and external 5-10 km areas, respectively; and 0.61%, 1.58% and 1.66% for national nature reserves, external 0-5 km areas, and external 5-10 km areas, respectively (Figure 8). Since 1980, the rates of reduction in the 0-5 km areas and 5-10 km unprotected areas outside the three types of important ecological spaces have become comparable to, and are greater than, those inside these ecological spaces. This shows that there is a gradient difference in the effectiveness of conservation inside and outside important ecological spaces. The reductions in areas external to ecological land for biodiversity priority areas was more than three times that of areas internal to them, and the reduction in areas external to national nature reserves was more than twice that of those internal to them. This indicates that the construction of important ecological spaces plays an important role in protecting important ecosystems and maintaining ecological security in China. However, the rate of reduction in key ecological function zones is comparable to the rate of reduction of such space in areas external to it. Attention should be paid to this by strengthening ecological protections for such areas.
Figure 8 Reduction rate of ecological land area in different important natural ecological spaces from 1980 to 2018

4 Conclusions and discussion

4.1 Conclusions

(1) In 2018, the proportion of area of ecological land to China’s important ecological spaces was 92.64%, being in absolute superiority with a good ecological background. This reflects the developmental orientation and current status of important ecological spaces in the country. Ecological land, in the context of the three important ecological spaces identified in this study, was mainly located to the west and north of the Hu Huanyong Line.
(2) From 1980 to 2018, ecological land within the important ecological spaces showed a trend of contraction, but rate of reduction in area was lower than the national average. This quantitatively reflects the effectiveness of measures to protect important ecological spaces.
The decrease in ecological land occurred mainly due to agricultural development while the increase in it resulted from the conversion of agricultural land. This shows that measures for the ecological protection of returning farmlands to forests and grasslands have been effective. On the contrary, urban and agricultural activities continue to encroach on and destroy ecological land. In general, changes in ecological land are stable in China. Ecological land has expanded in regions where projects for ecological protection, involving a conversion of farmland into forests and grasslands, have been implemented, and has contracted in the main grain-producing areas of the Northeast China Plain and the agricultural oases in Xinjiang. More effective control measures should be given to these areas.
(3) Differences were noted in the effectiveness of ecological protection within the three types of important ecological spaces considered here. As the ecological space subject to the first protection-related government initiatives, nature reserves occupied the highest ratio of the area of ecological land, exhibited the smallest rate of reduction in area, the least significant trend of reduction, the most stable change, and the best ecological protection effect. This also reflects the differences in the effectiveness of ecological protection measures among important ecological spaces.
(4) The ratio of the area of ecological land within important ecological spaces was higher than that of the surrounding external area, and the rate of reduction in it was lower than that of the external area. This reflects a clear difference in gradient in the effectiveness of external area protection. The construction of important ecological spaces is thus important for ecological protection.

4.2 Discussion

This paper evaluated the effects of the ecological protection of important spaces in China from both the temporal and the spatial perspectives through an integrated study of the spatial pattern and temporal process of ecological land, with the aim of providing a scientific basis for the spatial classification and zoning management and control of China’s national land. However, there are still some shortcomings to the work here: (1) National nature reserves, key ecological function zones, and biodiversity priority areas were established at different times in China. Control-related priorities and objects of protection were thus delineated according to different management-related needs. The boundaries overlap spatially, and some areas even have three overlapping categories. However, this paper separately analyzed the effectiveness of ecological protection of the three types of important ecological spaces, without considering the cumulative ecological effects of protection brought about by the overlapping boundaries. The cumulative effects of two or three types of overlap will be further explored and studied in the future work so as to provide more scientific support for management decisions. (2) The data used in the analysis were obtained from the Chinese national-scale land use database built by the Institute of Geographic Sciences and Natural Resources Research of the Chinese Academy of Sciences. The latest year for which the data were available was 2018. Considering this, we explored only the ecological effectiveness of the conservation of important ecological spaces in China ending in 2018. In our future studies, more recent data will be used for supplementary analysis.

References

Publishing order | Descend order by publishing year | Descend order by cited within
[1]
An G Q, 2018. Spatio-temporal evolution and conservation zoning of ecological land in Shandong Province based on EKC & Lorenz Curve. China Land Science, 32(9): 89-96. (in Chinese)

[2]
Deng H B, Chen C D, Liu X et al., 2009. Conception and function classification of regional ecological land. Acta Ecologica Sinica, 29(3): 1519-1524. (in Chinese)

[3]
Fan Z M, Zhang X, Li J et al., 2012. Transition trends of land-cover in national nature reserves of China. Acta Geographica Sinica, 67(12): 1623-1633. (in Chinese)

[4]
Fei J B, Xia J G, Hu J et al., 2019. Research progress of ecological space and ecological land in China. Chinese Journal of Eco-Agriculture, 27(11): 1626-1636. (in Chinese)

[5]
Gao J X, Xu D L, Qiao Q et al., 2020. Pattern construction of natural ecological space and planning theory exploration. Acta Ecologica Sinica, 40(3): 749-755. (in Chinese)

[6]
General Office of the CPC Central Committee and General Office of the State Council of the PRC (GOCPC), 2019 Guiding opinions on the establishment of natural reserve system with national park as the main body. http://www.gov.cn/zhengce/2019-06/26/content_5403497.htm in Chinese)

[7]
Guan Q C, Hao J M, Shi X J et al., 2018. Study on the changes of ecological land and ecosystem service value in China. Journal of Natural Resources, 33(2): 195-207. (in Chinese)

[8]
Han X M, Pu L J, Zhu M et al., 2010. Calculation of the area of effective ecological land in the region around Taihu lake. Chinese Agricultural Science Bulletin, 26(22): 301-305. (in Chinese)

[9]
Hou P, Wang Q, Fang Z et al., 2013. Satellite based monitoring and appraising vegetation growth in national key regions of ecological protection. Acta Ecologica Sinica, 33(3): 780-788. (in Chinese)

DOI

[10]
Hou P, Zhai J, Cao W et al., 2018. Evaluation on ecosystem changes and protection of the national key ecological function zones in mountainous areas of central Hainan Island. Acta Geographica Sinica, 73(3): 429-441. (in Chinese)

[11]
Huang L, Cao W, Wu D et al., 2015. Assessment on the changing conditions of ecosystems in key ecological function zones in China. Chinese Journal of Applied Ecology, 26(9): 2758-2766. (in Chinese)

PMID

[12]
Joppa L N, Pfaff A, 2011. Global protected area impacts. Proceedings of the Royal Society B: Biological Sciences, 278: 1633-1638.

DOI

[13]
Li G D, Fang C L, 2016. Quantitative function identification and analysis of urban ecological-production-living spaces. Acta Geographica Sinica, 71(1): 49-65. (in Chinese)

[14]
Liu J Y, 1996. Macro-scale Survey and Dynamic Study of Natural Resources and Environment of China by Remote Sensing. Beijing: China Science and Technology Press. (in Chinese)

[15]
Liu J Y, Kuang W H, Zhang Z X et al., 2014. Spatiotemporal characteristics, patterns, and causes of land-use changes in China since the late 1980s. Journal of Geographical Sciences, 24(2): 195-210.

DOI

[16]
Liu J Y, Liu M L, Zhuang D F et al., 2013. Study on spatial pattern of land-use change in China during 1995-2000. Science in China Series D-Earth Sciences, 46(4): 373-384.

[17]
Liu J Y, Liu W C, Kuang W H et al., 2016. Remote sensing-based analysis of the spatiotemporal characteristics of built-up area across China based on the plan for major function-oriented zones. Journal of Geographical Sciences, 71(3): 355-369. (in Chinese)

[18]
Liu J L, Liu Y S, Li Y R et al., 2017. Classification evaluation and spatial-temporal analysis of “production-living-ecological” spaces in China. Acta Geographica Sinica, 72(7): 1290-1304. (in Chinese)

[19]
Liu J Y, Ning J, Kuang W H et al., 2018. Spatio-temporal patterns and characteristics of land-use change in China during 2010-2015. Acta Geographica Sinica, 73(5): 789-802. (in Chinese)

[20]
Liu J Y, Zhang Z X, Xu X L et al., 2010. Spatial patterns and driving forces of land use change in China during the early 21st century. Journal of Geographical Sciences, 20(4): 483-494.

DOI

[21]
Long H L, Liu Y Q, Li T T et al., 2015. A primary study on ecological land use classification. Ecology and Environmental Sciences, 24(1): 1-7. (in Chinese)

[22]
Ma T H, Lv S, Lei C G et al., 2019. The spatial overlapping analysis for China’s natural protected area and countermeasures for the optimization and integration of protected area system. Biodiversity Science, 27(7): 758-771. (in Chinese)

DOI

[23]
Ministry of Environment Protection (MEP) et al., 2011. China Biological Diversity Protection Action Plan (2011-2030). Beijing: China Environmental Science Press. (in Chinese)

[24]
Nagendra, 2008. Do parks work? Impact of protected areas on land cover clearing. AMBIO: A Journal of the Human Environment, 37(5): 330-337.

DOI

[25]
Peng J, Wang A, Liu Y X et al., 2015. Research progress and prospect on measuring urban ecological land demand. Acta Geographica Sinica, 70(2): 333-346. (in Chinese)

[26]
Qi F, Li X W, Liu K, 2016. System research of natural ecological space use control. China Land, 12: 21-23.

[27]
Qu L L, Liu Y S, Zhou Y et al., 2019. Spatio-temporal evolution of ecologically-sustainable land use in the Luoxiao Mountains and responses of its ecosystem services: A case study of Jinggangshan city in Jiangxi province. Acta Ecologica Sinica, 39(10): 3468-3481. (in Chinese)

[28]
State Council of the PRC (SCPRC), 2010. The main functional area planning. http://www.gov.cn/zhengce/content/2011-06/08/content_1441.htm in Chinese)

[29]
Songer M, Aung M, Senior B et al., 2009. Spatial and temporal deforestation dynamics in protected and unprotected dry forests: A case study from Myammer (Burma). Biodiversity and Conservation, 18: 1001-1018.

DOI

[30]
Tang F L, Wang M J, Sun H Y, 2019. Reform path on management system of natural protected area. Forest Construction, (2): 1-5. (in Chinese)

[31]
Tang X M, Chen B M, Lu Q B et al., 2011. Primary exploration on the ecological land use classification in Beijing. Acta Ecologca Sinica, 31(14): 3902-3909. (in Chinese)

[32]
Wang J, Wang W, Qi Y et al., 2017. Classification system and spatio-temporal distribution of ecological land in China in the period of 1996-2012. Geographical Research, 36(3): 453-470. (in Chinese)

[33]
Wang W, Pechacek P, Zhang M X et al., 2018. Effectiveness of nature reserve system for conserving tropical forests: A statistical evaluation of Hainan Island. China. PloS One, 8(2): e57561.

DOI

[34]
Wen B, Zhu G L, Xia M et al., 2017. Ecological land classification protection based on the landscape security pattern in Yixing City. Acta Ecologica Sinica, 37(11): 3881-3891. (in Chinese)

[35]
Willcock S, Phillips O L, Platts P J et al., 2016. Land cover change and carbon emissions over 100 years in an African biodiversity hotspot. Global Change Biology, 22: 2787-2800.

DOI PMID

[36]
Xie H L, Yao G, He Y F et al., 2018. Study on spatial identification of critical ecological space based on GIS: A case study of Poyang Lake ecological economic zone. Acta Ecologica Sinica, 38(16): 5926-5937. (in Chinese)

[37]
Xu J, Xie G D, Xiao Y et al., 2019. Dynamic analysis of ecological environmental quality changes in national key ecological function areas in China. Acta Ecologica Sinica, 39(9): 3039-3050. (in Chinese)

[38]
Xu J, Zhou Y K, Jin X B et al., 2007. Discussing virgin land classification subsystem based on the protection of the eco-environment. Resources Science, 29(2): 137-141. (in Chinese)

[39]
Yang R J, Zhou S L, Wang X G, 2011. An overview of the study on ecological land. Journal of Environmental Management College of China, 21(2): 33-35. (in Chinese)

[40]
Yue J, Zhang X M, 2003. A discussion on classification of land use in China. Arid Land Geography, 26(l): 78-88. (in Chinese)

[41]
Yu F, Li X B, Zhang L J et al., 2015. Study of ecological land in China: Conception, classification, and spatial-temporal pattern. Acta Gcologica Sinica, 35(14): 4931-4943. (in Chinese)

[42]
Yu K J, Qiao Q, Li D H et al., 2009. Ecological land use in three towns of eastern Beijing: A case study based on landscape security pattern analysis. Chinese Journal of Applied Ecology, 20(8): 1932-1939. (in Chinese)

[43]
Zhang H Q, Wang L X, Jia B Q, 2004. A conception of ecological land use and its function classification in arid area in Northwest China. Chinese Journal of Eco-Agriculture, 12(2): 10-13. (in Chinese)

[44]
Zhang Z X, Zhao X L, Wang X et al., 2012. Land Use Remote Sensing Monitoring in China. Beijing: Star Map Press. (in Chinese)

[45]
Zhao D, Li F, Wang R S, 2009. Discussion on the concept and classification of urban ecological land. China Population, Resources and Environment, 19(6): 337-342. (in Chinese)

[46]
Zhao G S, Liu J Y, Kuang W H et al., 2014. Disturbance impacts of land use change on biodiversity conservation priority areas across China during 1990-2010. Acta Geographica Sinica, 69(11): 1640-4650. (in Chinese)

[47]
Zhou Y, Cai X C, Xie Y G et al., 2006. Ecological land use in typical karst area: A case of Qingzhen City. China Land Science, 20(5): 38-41, 62. (in Chinese)

[48]
Zhou Z, Meng J J, Qi Y et al., 2016. Importance of ecological lands and their pattern optimization in China: A review. Chinese Journal of Ecology, 35(1): 218-225. (in Chinese)

[49]
Zhu P, Huang L, Xiao T et al., 2018. Dynamic changes of habitats in China’s typical nature reserves on spatial and temporal scales. Acta Geographica Sinica, 73(1): 778-790. (in Chinese)

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