River and lake health is an important sign of the harmonious coexistence of human beings and nature, while rivers and lakes for human well-being is a concept with more profound connotation based on healthy rivers and lakes. Scientific understanding of healthy rivers and lakes is the basis for answering the connotation of rivers and lakes for human well-being. In what aspects does river and lake health reflect? How to effectively protect the health of rivers and lakes?

1.Concept of River and Lake Healt

River and lake health is a concept that arises with ecosystem health. Since 1970s, the concern about human living environment and resources issues has promoted the concept formation and development of river and lake health. Complete and systematic concept of river and lake health originated from European countries and America in 1990s.

By comparison of existing concepts of river and lake health at home and abroad, it is found that foreign concepts focus on the integrity and natural restoration degree of river and lake ecosystem, and gradually develop to balance the integrity and social services value of the ecosystem, while domestic concepts focus on the fulfillment degree of rivers and lakes in view of ecological and social services, start to concern about the restorability of ecosystem, pay attention to the balance between the ecosystem and social functions of rivers and lakes, and the sustainability of natural and social functions, and thus ascend to the philosophical realm of human-water harmony.

People’s yearning for a better life has kept updating and enriching the connotation of river and lake health. President XI Jinping and Minster of Water Resources E Jingping have made important speeches and instructions on the connotation of rivers and lakes for human well-being, which set a new tone of the River/Lake Chief System management in the new era based on river and lake health evaluation. And the scope of rivers and lakes in the concept of river and lake health should be extended from a single aquatic ecosystem to river and lake systems and waterfronts.

Hence, river and lake health concept under the new situation should be adapted to human cognition and the development needs of the times. The ecosystem structures, processes and functions of water areas and waterfronts shall be complete and of good disturbance resilience when rivers and lakes provide sustainable social services.

Beautiful New Wei River with Harmony Between Human and Nature (photo by Cheng Zhe)

2.Connotation of River and Lake Health

1)Ecosystem completeness

Ecosystem completeness indicates the integrity of three core elements of water areas and waterfronts, i.e. physical structure, water habitat and aquatic organisms. The physical structure includes river and lake system pattern, and aquatic and waterfront ecological spaces. Water habitat health is mainly reflected by ecological flow and water environment. Aquatic organisms shall include those not only in water bodies but also along waterfronts.

2)Ecological process restorability

Ecological process restorability means that ecological processes, such as structure, function, and material circulation and energy circulation of river and lake ecosystem, always maintain certain disturbance resilience, which usually include the resistance to and restorability of external disturbance. Healthy ecosystems of rivers and lakes shall possess certain resistance to and restorability of the impacts of nature and human activities. Disturbance resilience of ecosystem is an essential feature of healthy rivers and lakes. However, it remains at present as a difficult issue how to quantitatively characterize the disturbance resilience of ecosystem, which restricts the scientific evaluation of river and lake health.

3)Sustainability of river and lake functions

Sustainability of river and lake functions means that river and lake systems can meet the moderate needs of human activities, and support the sustainable development of economy and society. The connotation of sustainability of river and lake functions changes with the needs of human activities. Currently, the needs of human activities are mainly reflected in flood control, resources supply and water landscape. The social services of rivers and lakes is often difficult to characterize directly due to the needs of human activities and natural endowment of rivers and lakes, which is indirectly characterized by function fulfillment degree in river and lake health evaluation.

4)Natural attribute dominance

Natural attribute dominance means that river and lake health must be centered on the ecosystem health of rivers and lakes, with the absolute dominant position of natural attribute health highlighted. Rivers and lakes are, above all, natural ecosystems, of which the original ecological processes are inevitably impacted by human activities, possibly resulting in the changes of material and energy circulation features of ecosystems. River and lake ecosystem health is a premise to guarantee their social services. Only rivers and lakes with healthy ecosystems can meet the sustainable development needs of human society.

5)Differences of River and Lake Features

Differences of river and lake features mean that the differences of natural attribute and services of rivers and lakes shall be taken into account for different types of rivers and lakes. General evaluation shall be avoided to misjudge the health condition of different types of rivers and lakes. China is a vast country with diverse climate types and complicated geographic features, resulting in the diversity of natural features of rivers and lakes. Thus, river and lake subdivision and classification are the premise of evaluating river and lake health condition systematically and scientifically. Though some experts in China have preliminarily forwarded a set of candidate index system for river and lake health evaluation, it only refers to the natural attribute of rivers and lakes, which shall be improved in regard of river and lake ecological processes and services.

6)Developable health elements

Developable health elements mean that the key elements of river and lake health change with social demands, and then the connotation of river and lake health is kept developing. At the very beginning, river and lake health only concerned about the integrity of river and lake ecosystems. As the ecological civilization progresses in China, the proposal of rivers and lakes for human well-being highlights the connotation development of river and lake health from natural ecosystem health to the philosophical realm of human-water harmony.

The Didang Lake in Shaoxing, Zhejiang Province (photo by YUAN Yun)

3.How to Improve the Management of River and Lake Health?

1)Scientificity and standardization of river and lake health evaluation system

With the progress of the River/Lake Chief System in the whole nation, numerous evaluation systems of river and lake health have been tailor made. Some of them have been promulgated as local norms. To certain extent, respective evaluation system has referred to the research findings at home and abroad. And the natural features and services of local rivers and lakes have been considered in addition to the operability of river and lake health evaluation. But diverse evaluation systems are not favorable to hierarchical management of the River/Lake Chief System from another perspective.   And the scientificity of evaluation indexes with more focus on monitorability and evaluability and ignorance of representativeness has not been fully argued. Lack of standardization of river and lake health evaluation system inevitably increases the difficulty of hierarchical management of the River/Lake Chief System, leading to the impossibility of unified and strong supervision over the System.

Due to diverse climatic and geomorphic types, uneven distribution of water resources in time and space, and imbalance economic development between the East and the West and between the South and the North, the natural and functional features of rivers and lakes are various in China. It is unrealistic to carry out complete top-down study in such a short time. Therefore, in order to establish a scientific and standardized health evaluation system for rivers and lakes applicable to the whole country, it is necessary to combine the methods of top-down and extensive learning from others. On the one hand, professional research institutions can carry out the study on universal health evaluation system of rivers and lakes to ensure the scientificity of the system. On the other hand, it is necessary to fully consider and absorb the advantages of health evaluation systems of rivers and lakes in different places to ensure the operability of the system. By doing so, it is possible to form a set of standardized system of river and lake health evaluation with scientificity and practicability.

2)Effectiveness and intelligence of river and lake health management

River and lake health involves many industries, such as water conservancy, environmental protection, land use, municipal administration, shipping, chemical industry, etc. In the management process, river/lake chiefs must pay more attention to multi-party consultation, clarify problem sources, risk sources and responsible parties of river and lake health based on the objective results of health evaluation, make information public in real time, and supervise the responsible parties to rectify the problems by comprehensive use of legal, administrative and public opinion means on the one hand. On the other hand, it is necessary to improve the information level of river and lake health management by setting up databases of health problems, measures and countermeasures, using Internet of Things technology to improve the information level of river and lake health monitoring, and integrating the management process of real time monitoring, evaluation, response and supervision, so as to realize the intelligent decision-making of river and lake health management.

3)Normalization and legalization of supervision system

In terms of water supervision system construction, it is necessary to fully implement the regular evaluation system of river and lake health by a third-party professional evaluation to ensure the scientificity and objectiveness of river and lake health evaluation. In terms of responsibilities and staffing, it is necessary to promote the legalization of the River/Lake Chief System and related duties, enhance the performance ability of river/lake chief offices, and conduct professional and legal training for law enforcement teams to improve their professional competence. In terms of internal operation rules and regulations establishment, it is necessary to set up a reward and punishment system for river and lake health management, with incentives as the main and punishment as the supplement, and give full play to the dynamic and real-time health evaluation advantages under the River/Lake Chief System management to guide the quick detection and solution of problems and maintain the positivity and effectiveness of the management.

Note: This article is abbreviated. Full paper is available in No.6 of China Water Resources in 2020.

Authors: LI Yun (NHRI Vice President, Professor, Research Interest: Aquatic ecological environment management of rivers and lakes), DAI Jiangyu, FAN Ziwu and WANG Xiaogang.