CHANS-Net: The International Network of Research on Coupled Human and Natural Systems

Safaa Aldwaik, doctoral candidate, Clark University
Research Interest: Measurement of Land Transformation over time, Spatial Analysis and GIS, Remote Sensing

Title: Identifying Stationarity of Transitions Among Land Categories Over Time for Cross-site Comparison

This study presents research concerning cross-site comparison to characterize the land cover changes over time for several sites of the National Science Foundation's Long Term Ecological Research network. We examine transitions of land categories from three points in time to test whether the transitions during the former time interval are stationary with the transitions during the latter time interval. This method tests for stationarity even when time intervals are different durations or when the amounts of change in time intervals are different. The cross-tabulation matrices serve as the basis in this methodology. Cross-tabulation matrices from three points in time for the Plum Island Ecosystems site are examined. Computer code has been created to perform the same quantitative analysis for all participating sites.


Oskar Burger, postdoctoral research fellow, Stanford University
Research Interest: Human impacts on biodiversity in the tropics, causes of extinction in mammals, life history evolution, macroecological patterns in human demography.

Title: A modeling family tree: the abundance and distribution of modeling approaches in the CHANS
community.

We are reviewing modeling approaches within the family of projects formed by NSF’s CHANS and biocomplexity programs. We focus on grants that target the articulations of human societies with critical ecological resources and/or environmental constraints. The subject matter, research directive, and methodologies used by this grant family are incredibly broad; as, by requirement, all of these projects are highly interdisciplinary. Our aim is to identify patterns in the selection of modeling approaches by the CHANS community. Which modeling approaches are used most (and least) often, and why? Are there any specific approaches we should use more frequently? To accomplish this we will develop a taxonomy to organize this range of techniques and describe the connections among them. For instance, models will be initially categorized into computational, numerical, statistical, and analytical, and then further subdivided as needed. Thus far we have contacted 79 project PIs for copies of grants and publications. The documents we receive will constitute the sample of modeling approaches and their rationales. We are confident that some (most) of the audience will not agree perfectly with all aspects of our final taxonomy, but much of the value of this endeavor will emerge from the dialogue that any disagreements might promote. A preliminary examination of a subsample of CHANS grants suggests that computational models are exceptionally popular in this group whereas analytical approaches are rare, but these impressions will change with sample size.

Xiaodong Chen, doctoral candidate, Michigan State University
Research Interest: Human-Environment Interactions, Systems Modeling and Simulation, Conservation Biology

Title: Integrating household characteristics into targeting of conservation investments in payments for ecosystem services

Payments for ecosystem services (PES) have increasingly been implemented to protect and restore environmental benefits worldwide. Both flat payment scheme (where all participants are paid at the same price) and discriminative payment scheme (where payments differ according to the opportunity costs) have been used although the efficiency of conservation investments in different payment schemes can be substantially different. Previous studies on the cost-effectiveness of PES programs have targeted environmental benefits from PES programs based on land features. However, household characteristics of program participants have usually been neglected. We study the potential for targeting within China’s Grain-to-Green Program (GTGP, one of the largest PES programs in the world) by incorporating household characteristics of program participants in Wolong Nature Reserve. We found that household characteristics were significant determinants of opportunity costs of landholders for re-enrolling their GTGP land upon the maturation of the original contracts. By comparing environmental benefits obtained through different payment schemes, we found that the efficiency of conservation investment using cost-effective targeting in a discriminative payment scheme is substantially higher than that through a flat payment scheme. Moreover, both optimal cost-effective targeting and sub-optimal targeting can obtain substantially more environmental benefits than those from random selection of land plots in discriminative payment scheme. Our results suggest that cost-effective targeting and discriminative conservation payment tools, such as competitive auctions, can be used to substantially improve the efficiency of conservation investments in the GTGP and other PES programs in the world.

Nathan Engle, docotral candidate, University of Michigan
Research Interest: Adaptation, vulnerability, resilience, climate variability and change, water systems, governance and institutions

Title: Science, information, and governance in U.S. drought planning and management

The U.S. has recently experienced its share of extreme droughts, with particularly acute impacts occurring in the rapidly expanding Southeast and Southwest. Droughts will likely increase in severity, frequency, and duration with climate change in these regions. This leaves decision makers in both areas faced with managing a triple threat of population expansion, increasing urbanization, and climatic variability and change. Drought planning and management in the U.S. is coordinated at the state-level. The Federal government and local entities have traditionally operated on the periphery. Approaches, successes, and missteps have varied considerably within and between states in the Southeast and Southwest. As states begin to move from emergency response toward preparedness and mitigation planning and adaptive and integrated management, science and information are becoming more critical. Also with this shift, new roles for the Federal government and local entities as active participants in the planning and management process leave questions regarding which drought governance arrangements are the most effective, adaptable, and sustainable. This research investigates the relationships between science, information, and governance in Arizona and Georgia drought planning and management. Specifically, it examines the influence of these factors on adaptive capacity to extreme drought events and sustainability. It draws from data collected using an event history calendar in 35 of the largest community water systems, and a telephone questionnaire of key informants at the state and Federal levels. It identifies the potential conflicts, tradeoffs, and pressures at different organizational scales and what might work to alleviate these tensions.

Ryan Galt, assistant professor, University of California-Davis
Research Interest: Agrifood systems, political ecology, localization and globalization

Title: Adaptive and maladaptive coupling in Costa Rican vegetable production: explaining multi-scalar linkages between social and biophysical causes and outcomes in intensive agricultural systems

Using the case of intensive vegetable production in Costa Rica, I examine complex, multi-scalar linkages between biophysical and social processes. Focusing on local-scale drivers, I show the importance of topographic and climatic differences to agricultural production and socioeconomic differentiation. Resource-rich farmers respond to strong environmental variability by pursuing a spatial production strategy to exploit “environmental advantage,” a production advantage that accrues from the biophysical characteristics of a certain locale. This allows wealthier farmers to increase produce yield and quality, decrease pesticide use, and thereby obtain higher profit margins. In contrast, resource-poor farming households living in the same place maintain production in environments that are climatically problematic for vegetables, use pesticides more intensively, are more likely to be on the pesticide treadmill, and generally have lower profit margins. Thus, evidence exists for both adaptive and maladaptive coupling that is strongly influenced by farm families’ relative wealth. These local socioeconomic and biophysical conditions and processes intersect with extra-local drivers, the most important of which is industrialized nations’ food regulation acting from afar. These regulations generally impel export farmers to lower pesticide use relative to producers of the same vegetables for local markets. Thus, coupling in terms of reducing pesticide use and adopting agroecological practices is also strongly driven by extra-local food regulation, whereas local food regulation has little effect on farmers' pest and agroecological management. Conclusions discuss political ecology's contribution to co-evolutionary/feedback thinking, and theoretical issues in identifying inter- and inner-actions in social-biophysical systems at multiple scales.

Lily House-Peters, graduate research assistant, Portland State University
Research Interest: Coupled human and natural systems relating to urban water demand, supply, and equitable access, with emphasis on arid environments

Title: The Challenge of Predicting Future Urban Water Demand: A System Dynamics Modeling Approach

Previous research investigating urban residential water demand has either employed social science methods to examine human attitudes and behaviors or statistical models to explain the impacts of climate and other biophysical processes. The lack of integration of social science and natural science methods to analyze patterns of urban water demand has resulted in limited understanding of the coupled natural and human systems. Furthermore, while statistical models have the ability to investigate multiple determinants, both social and ecological, they do not model the effects of complex feedback loops among variables within an ever changing environment. System dynamics modeling improves upon traditional statistical models by more accurately representing the complexity and dynamism inherent in coupled human and natural systems. This research examines residential water demand in Hillsboro, Oregon, a rapidly growing municipality in the Portland metropolitan area, using a system dynamics modeling approach to examine the multiple determinants, stresses, and interactions that influence urban water demand. By incorporating dynamic ecological, demographic, behavioral, and land use variables, the model accounts for the complex relationships among each of the variables and elucidates potential tipping points, beyond which abrupt and surprising changes may occur. The model is run multiple times simulating changes to the system for 55 years (1995 – 2050) under various climate change, population growth, land use change and conservation scenarios. The findings of this study have significant policy implications and reveal the potential for system dynamics modeling to be integrated in decision-support tools in a changing environment.

Tricia Knoot, postdoctoral research associate, University of Wisconsin-Madison
Research Interest: I am interested in understanding the social capacity to adapt and manage for resilient coupled human and natural systems. Specifically, I seek to provide a synthetic understanding of multi-scale factors that shape sustainable natural resource use, including system feedbacks, thresholds, and the social relationships that contribute to learning and innovation. Information gained can be directly applied to informing natural resource management and policy decisions and enhancing the environmental outcomes of the decision-making process.

Title: Social capital and private forests: the role of personal networks in environmental decision-making

Most forestland in the U.S. is in private ownership, consequently a variety of ecosystem services available to society are dependent on sustainable land management decisions by individual landowners. Landowner decision-making is a complex process and shaped by individual landowner attributes and social context. For example, forest owners often rely on family and friends, as well as forestry “experts,” for information and technical assistance. Theory and analysis of social relationships, i.e. social networks, emphasize the importance of network structure to the flow of beneficial resources among actors. However, social network structure surrounding private forest management has received little attention. We evaluate the influence of social networks on sustainable private forest management and provision of ecosystem services. We interviewed 44 landowners in Wisconsin, and evaluated their personal, i.e. egocentric, networks and use of voluntary Best Management Practices (BMPs) for water quality during a recent timber harvest. Concurrently, we interviewed 28 forestry professionals to determine the impact of network structure on their capacity to meet landowners’ needs. Preliminary results suggest an increase in landowner ties to experts, specifically a public forester, increases BMP implementation, but may also increase landowners’ perceived difficulty with the management process. Furthermore, forestry professionals’ social networks appear to be influenced by a public policy tool—i.e. tax incentive program—which in turn affects professionals’ capacity to impact landowner behavior. We discuss the methodological challenges but important contribution of understanding social networks surrounding land management decisions. We also stress the need for improved understanding of the impact of public policy on social networks, individual decisions, and ecological outcomes.

Pedram Rowhani-Ardekani, postdoctoral fellows, McGill University
Research Interest: Global Land Use and Land Cover Change, Human-Climate-Environment Interactions, Food and Human Security, Remote Sensing, Earth System Science, Global Environmental Change, Biodiversity.

Title: The influence of changes in climate means versus changes in climate variability on crop yields in Tanzania

With over 1 billion undernourished people in the world a better understanding is needed on how and where we produce food. This situation may even get worse with the predicted change in climate. This necessitates cross-disciplinary research analyzing the effects of climate on crop production. Our study uses statistical methods to measure the relationships between temperature and precipitation, and crop production in Tanzania where agriculture represents around 46% of its GDP. Agriculture in Tanzania is mainly rainfed with little chemical input, making crop production very sensitive and vulnerable to climate. One of the main qualities of this study is the use of detailed climatic data using precipitation and temperature records from 20 gauge stations around the country as well as information on crop production and harvested area at the subnational level. Having high-resolution data will provide us more detailed information on more local processes. Moreover, besides looking at the impacts of changes in climatic means, this study will also measure the impacts of intra-seasonal changes in precipitation and temperature. First results show a decline in yields with rising temperature. As the IPCC has predicted an increase in extreme climatic events as well as in temperature this study will give insight on the potential impacts on crop production, especially in food insecure regions.

Steven Vanek, doctoral candidate, Cornell University
Research Interest: Nutrient management and nitrogen fixation in smallholder agriculture; linkages to food security

Title: Smallholder farming in northern Potosi, Bolivia: challenges to local adaptive coupling in an Andean setting

Highland farmers in Northern Potosí, Bolivia practice mixed crop/livestock subsistence agriculture in which extensive rangeland grazing provides nutrients in manure for crop production. Their farms, communities, and outside networks represent a coupled human and natural system where we might expect tight coupling between the environment and management. We analyze soil degradation as a driver of this system and test whether soil nutrient balances correlate to household food security, a locally felt signal necessary for adaptive coupling to sustain productivity. Nutrient balances reveal that soil erosion is a major driver that undermines productive capacity. Farmers’ dependence on ecosystem services in range and crop areas would make this degradation signal seem effective in causing farmers to reduce soil erosion rates. Reduced food security shows evidence for this signal at household scales. However, other processes at both local and regional scales make adaptation difficult and foster maladaptive coupling. Locally, buffering of soil nutrient stocks delays farmers’ perceptions of degradation compared to the nutrient balance approach. Increased grazing of common rangeland enables higher manuring rates with low immediate cost and substitutes for more costly and innovation-intensive reductions in erosion. Lack of credit or other incentives and reduced food security also inhibit households’ adaptive ability. Regionally, outmigration and off-farm income play a role in coping with reduced on-farm productivity and damping the coupling signal. Our work suggests that both local and cross-scale factors play a role in limiting the perception and the response to environmental signals for adaptive coupling by smallholder farmers.

Sintana Vergara, doctoral candidate, University of California-Berkeley
Research Interest: Sustainable solid waste management, consumption, waste treatment, life cycle assessment, industrial ecology

Title: Valuing the climate benefits from informal waste recycling in Bogotá, Colombia

How waste is managed – whether as a nuisance to be disposed, or as a resource to be reused – has the potential to either contribute to or help mitigate climate change, an urgent global challenge that threatens human security and the stability of our biome [Bogner et al 2007]. Material recycling decreases the amount of waste that must be disposed and offers the potential to mitigate many environmental burden by decreasing the demand for raw materials and energy. Developing cities remain centers of material recovery and reusethrough the participation ofpeople who scavenge goods from city waste and resell the materials to manufacturers. Waste management systems in developing nations face pressure from increased urbanization and waste generation, the quest for “modernization,” prompting some to view the informal waste sector “as an impediment to development” [Mitchell 2008], and a push towards landfill-centered waste management by the Clean Development Mechanism, a fund that finances climate change abating projects in the Global South and tends to fund landfills [Wilson 2007]. The climate-mitigating benefits of informal recycling have not been quantified [Gutberlet 2008; McDougall 2001] but must be; doing so would allow for its comparison with formal waste technologies and would facilitate the integration of this sector into socially and environmentally responsible waste management plans. In collaboration with the Association of Recyclers of Bogotá (ARB), I use an Industrial Ecology framework to map the waste flows in Bogotá, home of the “the most dynamic scavenger cooperative movement in the world” [Medina 2000]. Though preliminary results show that informal recycling in Bogotá is responsible for the diversion of 17% of the waste stream [Gomez 2004], I recognize that waste flows are dynamic, and understanding the driving forces behind the recycling of certain materials, and how the location of waste production affects its fate is key to understanding the environmental impacts of informal recycling. This project is the first that seeks to quantify the environmental services from informal waste recycling, and also provides a methodology that is replicable in other locations.