5. Conclusions and Outlook
Due to rapid urban development, the environmental hotspot has changed
from initial supply services to the later regulation function, and then
to the current cultural service function. Urban development has
gradually shifted from the initial orientation to economic construction
to people-oriented development. The blue-green space system, in which
water bodies and green spaces are intertwined and continuously
integrated, can promote the sustainable development of urban natural
systems, the construction of livable cities, and the improvement in
urban vitality. In the review, the development process of the blue-green
space evaluation index system is summarized because of previous studies.
The relationships between water bodies, green spaces, and blue-green
spaces and the complex structures and functions of blue-green spaces are
analyzed as a composite ecosystem in order to provide the basis for
subsequent blue-green space planning.
In existing studies on blue-green spaces, blue spaces and green spaces
are separately evaluated and a combined evaluation index system for
blue-green spaces is not available. The suggestions are provided as
follows:
1) The indices of water bodies and green spaces should be
comprehensively considered, in order to evaluate the blue-green space.
The blue-green space is a complex system composed of water and green
spaces. The mutual influence between water and green spaces form
ecological service functions, unlike that in a single water body or a
green space. Therefore, in the evaluation of a blue-green space, it is
necessary to select indices considering water and green spaces for
comprehensive evaluation.
2) People-oriented urban construction is significant. Urban blue-green
spaces have environmental landscape functions and ecological service
benefits and provide residents with space for recreational activities,
thereby increasing residents’ physical activities, promoting social
interaction and integration, and bringing positive effects to the
public’s physical and mental health. In other words, the construction
quality of blue-green spaces is closely related to the happiness and
quality of life of urban residents. Therefore, the selection of indices
should reflect the ecological service function or social function for
human beings.
3) Multi-scale and periodic evaluation are recommended. According to the
size of the range, blue-green spaces can be classified into large
blue-green spaces and micro blue-green spaces. According to different
scales of evaluation objects, a multi-scale evaluation index system with
the hierarchy of “city-district-community-people” can be constructed
to cover the macroscopic whole area and an individual. In addition, the
constructed evaluation index system should be based on the overall
planning of urban and rural areas and the “people-oriented” planning
idea. It is necessary to improve the supervision mechanism and establish
a periodic evaluation system. Long-term monitoring and evaluation can
provide the basis for improving urban planning quality and subsequent
construction.