With the rapid socio-economic growth at the global level, overexploitation of basal resources due to mass production and consumption has led to disturbance of natural biogeochemical cycles of macronutrients, such as nitrogen and phosphorus (Sutton et al. 2013). Such nutrient imbalances have caused serious environmental issues, such as cultural eutrophication and biodiversity loss, resulting in deterioration of ecosystem services (Anderson et al. 2002, Hoagland et al. 2002, Smith and Schindler 2009). At present, it has been recognized that these issues are so common and prevalent throughout the planet, posing a risk to sustainable human development (Rockström et al. 2009). Issues derived from nutrient imbalances emerge at the watershed level because the watershed itself is a spatial unit of water and nutrient cycles. Since such watershed issues are complicatedly entangled with a variety of local issues as cause and/or effect, watershed management has difficulty in reconciliation with the local issues. Here our project (hereafter, e-REC) proposes adaptive watershed governance for the inclusive solution to both local and watershed issues through cross- level interactions between macro- and microscopic approaches, addressing a shared goal to enhance social-ecological health of watershed systems, which are indicated by three components, biodiversity, nutrient cycling and well-being.

In order to solve environmental issues emerging at the watershed level, conventional watershed management, in which governments and researchers take the initiative, have taken institutional, technological and economic approaches in their beliefs that identification and elimination of causal factors for such issues result in the overall solution for every stakeholders (Abell et al. 2002, Bressers and Kuks 2004, ILEC 2005). However, they have been often confronted with difficulty in the solution to local issues because there exist tension and conflict for priority to the solution between the local and watershed levels. Considering such hierarchy of watershed system, the previous RIHN Project (RIHN Project 3-1 2007, Wada 2009) proposed a basic idea on how to balance out between the local and watershed issues in the watershed management. Taking advantage of its deliverables, we are engaged in the adaptive watershed governance for the inclusive solution to local and watershed issues, in order to test its utility and applicability to a wide range of watersheds in the world toward the ultimate solution of nutrient imbalances as the global environmental issue.

The concept of proposed watershed governance is based on a working hypothesis, so-called ‘four-gear hypothesis’, that biodiversity, nutrient cycling and well-being are interdependent on each other through community activity. As the microscopic social- cultural approach to enhance these components at the local level, we begin with participatory and action researches to reinforce human-nature relations through community activities for conservation of ‘familiar nature’, i.e., natural objects of special significance to local life and livelihood. As the community activities promote sharing of cultural values of the familiar nature among the community members, on one hand, community-based well-being is enhanced with accumulation of bonding social capitals. On the other hand, such conservation activities can enhance nutrient cycling directly and/or indirectly through ecological functions of biodiversity.

As the macroscopic scientific approach, we conduct synoptic researches to visualize spatial pattern of biodiversity, nutrient cycling and well-being at the watershed level. If community activities can contribute to enhancement of biodiversity, nutrient cycling and well-being, they may benefit stakeholders other than the community members in ways not easily registered by the local cultural values, but inspired by the social-ecological health of watershed. In disseminating such scientific knowledge to the public, the e-REC facilitates social involvement in the community activities by non-community members who appreciate the value of social-ecological health. This shared awareness allows accumulation of bridging social capitals and further enhances community- based well-being. As scientific knowledge is extensively shared among stakeholders in the watershed, community members may gain societal appreciation and institutional support, resulting in community empowerment. To facilitate sharing of such knowledge and experience of community and research activities through the watershed governance, we hold seminars and workshops. We also construct an integrated model, which will provide as a participatory scenario-making tool for diverse stakeholders to envision social-ecological health of watershed system.

To test the four-gear hypothesis, we are engaged in the watershed governance in two contrasting

watersheds in Asia: the Yasu River sub-watershed of Lake Biwa (Japan) as a model of infrastructure- oriented society and the Silang-Santa Rosa sub-watershed of Laguna de Bay (Philippines) as a model of high-nutrient loading society. In the former watershed, 4 rural communities from the up- to downstream areas and 1 coastal urban community are selected as study sites, and 1 rural community in the midstream area of the latter watershed. Through within- and between-watershed comparison, we discuss what social-ecological factors affect utility of our governance approach and consider its applicability to other watersheds.

In the e-REC, 7 discipline-based research units are organized to test working hypotheses on natural and social processes of the watershed governance, and a total of 15 site- or issue-specific working groups to co-work with stakeholders at the study sites. We are also collaborating with two core projects (Environmental Traceability Project and OpenTS Project) in Core Program to apply their theories and methodology to our study system. Thee-REC can contribute to Program 2 because it seeks for the solution to conflicts for multiple resource uses and priority issues among diverse stakeholders at multi-spatial scale, in terms of fairness and equity.

 

 

CONTRIBUTION TO THE PROGRAM 

Program 2 explores wise and fair management systems capable of addressing multiple resource uses by multiple stakeholders at multi-spatial scale. Through the watershed governance proposed by e-REC, we aim to seek for feasible approaches, which can lead to the solution of conflicts for the multiple resource uses and priority issues among diverse stakeholders at local and watershed levels, in terms of fairness and equity. It is expected that such a governance approach can be a promising way to wise and fair management of ecological resources, such as water, nutrients and biodiversity, which extend over the multi-spatial scale. 

In the Silang-Santa Rosa sub-watershed of Laguna de Bay, for instance, the society has a lot of social-environmental issues attributed to disordered uses of groundwater resources by a variety of stakeholders (Lambino et al. 2018). Based on our synoptic research showing that some household wells have high concentration of groundwater nitrate with the potential risks for human health, such 15 18 as a blue baby syndrome, we conducted nitrateδ¹⁵ N-δ¹⁸O dual isotope analysis to identify sources of the nitrate pollution, collaborating with a core project (Environmental Traceability Project) under the direction of Core Program. This collaborative research suggested the possibility that the groundwater nitrate pollution can be derived partly from chemical fertilizers used in the upstream croplands and partly from septic wastes in the midstream community (Privaldos et al. 2018). While sharing of our assessment results at the stakeholder assembly last November, our project contributed to conclusion of MOA between a national governmental institute, Laguna Lake Development Authority, and a local government, City of Santa Rosa, for installation of facility to monitor water quality. It is expected that sharing of such scientific knowledge will be useful for wise and fair management of water resources in this watershed in the future. 

Our synoptic researches also revealed that land conversion from forest to agricultural and residential areas is a driver for nutrient imbalances and resultant biodiversity loss in the Laguna de Bay Watershed (Peralta et al. 2019, 2020). In general, globalization has facilitated the import of forestry and agricultural products from developing to developed countries, which exploit natural resources from the latter, imposing heavy environmental loads on their watersheds though this may not be the case anymore in the Laguna de Bay Watershed, in which agricultural products are currently provided mainly for domestic consumption. In order to understand unfairness of resource uses at the multi-spatial scale, we have the advantage of synergy with the Program 2 through incorporation of international frameworks into our research scheme. Considering the international unfairness of resource uses under globalization, our collaborative research intended to conduct phosphorous flow analysis at the multi-spatial scale from watersheds to the globe in order to assess phosphorous footprints. The phosphorous flow analysis at the national level was already applied to the Japanese society by a member of e-REC (Matsubae et al. 2009) and the global one is ready for publication (Oita et al. under review). To fill the gap of multi-spatial scale, we constructed the phosphorous flow analysis for a social-ecological system of the Lake Biwa Watershed. 

As another case of multiple resource uses within the watershed, we treat with macrophyte overgrowth and composting in the south basin of Lake Biwa, collaborating with a core project (OpenTS Project) which seeks for open governance to transcend knowledge gaps among stakeholders. At present, this project is developing portal and local currency systems to share knowledge and experience of macrophyte resource uses under collaboration with NPOs and local governments. Through application of these systems, we will examine how open data and open governance can contribute to fair and sustainable uses of ecological resources by diverse stakeholders. 

1. PROJECT PROGRESS DURING FULL RESEARCH 

 

1) Outcomes of project as a whole 

Based on results of synoptic researches, we constructed relation diagrams to show how human activities can affect biodiversity and nutrient cycling through nutrient imbalances in the two watersheds. Our comparative study contrasted human impacts on stream and lake ecosystems between the two watersheds. In the Lake Biwa Watershed in which domestic and industrial phosphorous (P) loadings are reduced by sewage treatment systems, agricultural activities are a primary driver for biodiversity loss and thus alteration of biodiversity-driven nutrient cycling. In the Laguna de Bay Watershed in which sewage treatment systems have not yet been established, by contrast, urbanization is a primary driver for stream biodiversity loss through heavy domestic P loading, while agricultural nitrogen loading caused groundwater pollution (Privaldos et al. 2018) and nutrient imbalances in coastal waters. 

In the Yasu River sub-watershed, the synoptic questionnaire survey on subjective well-being suggested that social capitals and interaction with nature can affect the well-being. 

In parallel, we demonstrated that community activities can affect biodiversity and nutrient cycling at the local level. Our comparison suggested that familiar nature as a part of biodiversity can play a key role in driving four gears at the local level though there is variation in its relative significance among the communities. We also discussed what social-ecological factors can affect consequences of community-based governance. In the Laguna de Bay Watershed, by contrast, biodiversity was not always effective in the community-based governance. Such a difference can be attributed to ecological and social-historical backgrounds of the two watersheds. 

Seminars and stakeholder assemblies were effective in facilitation of knowledge-sharing among diverse stakeholders and subsequently in their involvement in the governance activities. 

 

2) Specific activities of working groups

a) Forest conservation Working 

In the upstream forest community, we found that actor groups who are engaged in forest conservation have diversified community activities with loose connection. For them, forest-derived values are expanding from profit and property to fun under declining forestry but their intention is consistent to return the profit from the forests to their own community for its financial independence.

 b) SATOYAMA conservation Working 

In the midstream farmer community, we demonstrated that action to conserve familiar nature, which serves as indigenous environmental indicators, was effective in promotion of eco-friendly farming, resulting in increased wetland biodiversity and reduced P loading from the rice paddies (Asano et al. 2017, 2018).

c) Nursery rice paddy Working 

We revealed that an endemic crucian carp can home to its natal rice paddy using otolith Sr isotope analysis. A seminar was effective in sharing of local and scientific knowledge on nursery rice paddy among participants, making this activity attractive to diverse stakeholders.

 d) Lagoon restoration Working 

In a coastal community in which a public program on lagoon environmental restoration was recently completed, we conducted biodiversity and nutrient researches in lagoons, using advanced technique, such as environmental DNA, δ18Op analysis and otolith Sr isotope analysis (Wu et al. 2019; Yi et al. 2019). We shared scientific knowledge on familiar nature as well as on water quality with community members who have planned to practice community activities.

 e) Macrophyte composting Working 

We demonstrated that macrophyte composting has a positive effect on plant growth through alteration of soil microbial communities and genetic diversity related to P metabolism (Osono et al. 2015, Matsuoka et al. 2019). We also conducted questionnaire survey on macrophyte issues targeting coastal urban communities under collaboration with OpenTS Project to discuss macrophyte resource utilization with stakeholders through workshops (Kondo et al. 2019). 

 f) Yasu River Working 

Using the δ¹⁸ Op analysis, we visualized spatial pattern of P cycling in the whole catchment of Yasu River (Ishida et al. 2019). Structural equation modelling revealed that land uses have significant effects on water quality and biodiversity in stream ecosystems (Ko et al. 2018). Such alteration in turn affected trophic transfer of nutrients within the food webs (Ishikawa et al. 2017). 

 g) Lake Biwa Working 

We assessed the relative importance of P loadings from rivers and groundwaters into the lake basin, using ²²²Rn concentration measurement and δ¹⁸ Op analysis. In the Yasu River sub-watershed, the P loading from groundwater was estimated as twice as that from river water.

h) Nutrient flow analysis Working 

P flow analysis for the Lake Biwa Watershed using input-output table of Shiga Prefecture revealed that fertilizer-derived P accounts for more than half of external P inflow from outside the prefecture with 12.5% of P recycling rate. We estimated that P output can be reduced by ca. 5.6% if lodging and food service industries serve eco-friendly products and local fish food in Shiga. 

 i) Human well-being Working 

Synoptic questionnaire survey in the Yasu River sub-watershed revealed that community trust has a positive effect on subjective well-being as social bond at individual level and a negative effect as social norm at community level, while general trust enhances the subjective well-being at watershed level (Fukushima et al. 2020). It also showed that forest-related well-being is enhanced when interacting with forest organisms, suggesting that biodiversity-driven well-being.

 j) Integrated model Working 

We constructed an integrated model to examine interrelation among the four social-ecological components, incorporating our synoptic data into structural equation modeling. We found that there exists decoupling between community activity and biodiversity at the watershed level, suggesting the need for action research to reinforce human-nature relations at the local level. 

 k) Laguna Lake Working 

For a midstream farmer community of the Silang-Santa Rosa sub-watershed, we conducted action research to conserve a sacred spring as the familiar nature because biodiversity conservation is less effective in community empowerment in this watershed with low biodiversity (Siapno et al. 2018). In parallel, stakeholder assemblies have been held under initiative of watershed management council, regarding groundwater as boundary objects (Lambino et al. 2018).

 l) Governance method Working 

We created matrix tables to discuss utility of our governance approach and social-ecological factors affecting its consequence though within- and between-watershed comparison. 

1)     Since the Philippine Government ratified the Nagoya Protocol of CBD(Convention on Biological Diversity) on ABS (Access and Benefit Sharing) in the way of our joint research, we confronted with a regal problem related to biological specimens which were imported into Japan in transition of the protocol implementation. Considering that it took long time (more than a year) to obtain the prior informed consent (PIC) from the provider country, institutional logistic support is needed to prepare for the conclusion of the mutually agreed terms for ABS (MAT) with the counterpart organization before acceptance of the full research.

 

2)     In order to maintain a trust with stakeholders, especially with local communities, after the completion of full research, it is desirable for RIHN to keep partnerships with them as a transdisciplinary research institute. Also, follow-up surveys by the core program are recommended to assess social outcomes of the completed research because societal changes generally take longer time than the full research period. To disseminate such social outcomes to the public as well as to the academia, the previous system, i.e., Completed Research (CR), should be reconsidered to support publication after the completion of full research.