Landscape connectivity analysis for the forest landscape restoration: a case study of Gongyi City

Abstract

Landscape connectivity is the degree to which the landscape facilitates or impedes the movement of organisms or ecological processes among patches. The maintenance of landscape connectivity is one of the key issues in ecological conservation and construction. The Conversion From Farmland to Forest is a long鄄term ecological project in China.However, along with the rapid urbanization and industrialization in China, the relationships between landscape connectivity and forest restoration has not been fully explored. The emergent questions concern the connectivity of restored forest landscapes, whether or not this connectivity benefits the local flora and fauna, and how to evaluate the importance of agricultural patches that are to be converted prior to the onset of forest restoration.Based on the theory of landscape connectivity, the forest connectivity in Gongyi City, Henan Province is investigated using indicators such as the number of components ( NC) , the integral index of connectivity ( IIC) and the importance value of IIC ( dIIC) . With the help of GIS, we examined how landscape connectivity of the forest in the hilly and low mountain areas varied according to distance threshold values ranging from 50 meters to 10000 meters, and identified the most

Functional Connectivity Analyses and Construction Strategies of the Structure of Green Space Network in Haidian District of Beijing

“…Based on the Graph Theory ① , Lucı'a Pascual-Hortal and Santiago Saura first employed functional connectivity index to directly describe the structural characteristics of ecological processes within an urban green space network, including seed dispersal, animal migration, and gene flow [11] , which would better inform protection and restoration of the structure of green space network. Recent studies on functional connectivity of green space network mainly concentrate on how and why a connectivity changes [12] , evaluation of the status quo of green space structure [9][13]~ [15] , optimization of spatial construction [16] [17] , etc. For example, Chen Chundi [14] proposed a green space structure by identifying a series of key patches and corridors for the city of Christchurch, New Zealand according to the maximum seed dispersal distance of Dacrycarpus dacrydioides; Chen Jie [16] proposed a methodology to identify important patches in forest restoration based on integral index of connectivity to improve the construction and optimization of green spaces.…”

“…Shedding a light on Haidian District of Beijing, this research examines the structure of urban green space network of varied types, in order to inform the pattern improvement of urban green space system. 散 [4] ，降低种群灭绝的风险 [5][6] ，保护生物多样性 [7] [8] 。 景观连接度包含斑块间空间实体格局的结构性连接和整体生态过 程的功能性连接两方面 [9] ，是衡量生态过程与功能联系的稳定性、定 量描述绿地结构特征的重要指标。在高开发强度的城市区域，恢复绿 地网络的结构性连接非常困难，而可保障生态过程完整与连续的功能 性连接则具有较高的可操作性 [10] 。路西亚•帕斯库尔-霍托尔和桑迪 亚戈•索拉基于图论 ① ，提出运用功能性连接指数来直观反映城市绿 地中种子传播、动物迁移和基因流动等生态过程的网络结构特性 [11] ， 为保护和修复绿地网络结构提供了依据。近年来，针对绿地网络功 能性连接的研究主要集中在连接度的演变与动因 [12] 、绿地结构的现状 评价 [9][13]~ [15] 、空间格局的构建优化 [16] [17] 等方面，例如陈春娣等 [14] 基于新 西兰鸡毛松(Dacrycarpus dacrydioides)种子的最大传播距离构建了新 西兰基督城的绿地结构并指出关键斑块和廊道，陈杰等 [16] 海淀区位于北京市中心城区的西北部(图1)，面积430.8km 2 [18] ， 属暖温带半湿润大陆性季风气候，多年平均降水量为585mm，年均蒸 发量1 800～2 000mm。全区位于华北平原北部边缘与太行山余脉交汇 地带，可大致分为西部海拔100m以上的山区和东部平原两个部分；境 内有大小河流近10条，绿化覆盖率达到52.2% [19] 。以"三山五园" ② 为 核心的历史文化资源丰富；高校林立，科技文化资源得天独厚；城镇 化程度高。…”

Analysis of Forest Landscape Restoration Based on Landscape Connectivity: A Case Study in the Yi River Basin, China, during 2015–2020

“…However, with the process of large-scale urbanization and the loss of natural habitats in China, landscape connectivity has received increased attention in recent years. Research on landscape connectivity has been widely applied in fields such as Land 2021, 10, 904 2 of 11 the construction of landscape security patterns [6] and urban ecological networks [7,8], assessments of urban land suitability [9,10] and suitable habitats for wildlife [11], land use changes and its effects on landscape connectivity [12][13][14], etc. Previous studies have shown that landscape connectivity has significant impacts on forest ecosystem functions, such as seed migration and dispersal, animal migration, gene flow, infiltration interference and soil erosion, and further influences the completeness, sustainability and stability of forest ecosystems [14][15][16][17].…”

“…In China, the Returning Farmland to Forest Program (RFFP) is part of an FLR scheme. This grand ecological program has the largest investment, is the most policy-oriented, has the broadest coverage, and has the highest level of public participation [14]. Henan province initiated the RFFP in 2000, and this program was fully operational in 2002.…”

“…The selection of this research period was to assess the implementation of the two plans, such as the status of FLR and the variation of forest landscape connectivity (FLC). However, whether the restored forest landscape is more conducive to promote the survival and development of local organisms, and how to assess the importance of cropland patches that need to be reforested before FLR, are questions which remain unclear [14,[21][22][23].…”