Urban forest management and governance in Latin America and the Caribbean: A baseline study of stakeholder views

Cities in the Latin America and Caribbean (LAC) region and around the world are setting long-term greening goals that include planting more trees and increasing green cover. Research in LAC cities has mainly focused on biodiversity and vegetation, with little understanding of the mechanisms underlying the decisions through which stakeholders achieve urban greening. Exploring stakeholders’ views about urban forest management and governance can provide us with an opportunity to identify needs and research gaps for urban greening and urban forestry in LAC. To our knowledge, there has never been a region-wide empirical study to capture these stakeholder views. Here we explore how stakeholders working in urban forestry in LAC, including governmental, and non-governmental professionals, define urban forests, and view management and governance issues as well as educational opportunities. We used an online survey based on a combination of open- and closed-ended questions. The survey was delivered to participants at the first two regional conferences on urban forests in LAC organized by the United Nations. We collected 91 responses from stakeholders working in 50 different cities of varying population sizes across 6 LAC bioregions. Most respondents considered parks, planted green corridors, street trees, and remnant forests in urban and peri-urban areas as components of urban forests. Stakeholder views on management and governance were divided in two distinct perspectives, one dominated by public participation issues, and another one related to operational issues. Most respondents considered operational and management tools for urban forests to exist in LAC cities, but they disagreed on the existence of inventories, long-term strategies, and ways for the public to engage in urban forestry. Responses also revealed that some educational opportunities, such as arboricultural certification, are still relatively scarce and in high demand in the region. This study provides a regional baseline and first insights into a more diverse view of urban forestry which could be enriched with more empirical studies in the future.     

Development of urban forest policy-making toward governance in the Republic of Korea

This research attempts to analyze the emergence and development of urban forest policies at the national and local levels in the Republic of Korea. The Policy Arrangement Approach (PAA) is applied as an analytical frame to analyze changes in the urban forest policies of the central and local governments. The PAA offers four dimensions that can be used to describe and analyze the policy process: actors, power, rules of the game and discourse. The research findings indicate that a discourse on sustainable development in which the social functions of forests are taken into account substantially contributed to the creation of urban forest policies. This discourse contributed to the activities of actors and their power relationships and to the introduction of new rules relating to Korean urban forest management. In addition to public actors, private actors have also participated in creating and managing urban forests. Various partnerships among actors were formed for urban forest management. Civil society exercised its power to design and manage urban forests through increased voluntary participation. The legislation relating to urban forests functioned as a framework for urban forest policies at the national and local levels. Agreements acted as new rules governing the relationships among the actors who were involved in urban forest management. In conclusion, the four dimensions of policy arrangements relating to urban forest policy, and the interconnections among these dimensions, elucidate the emergence and dynamic development of urban forest management in the direction of governance at the national and local level in the Republic of Korea. In particular, discourse about forests was a substantive dimension of policy arrangements, and it influenced changes in the identity of the participating actors and their power. The discourse contributed to the establishment and development of rules for urban forest management. Thus this research provides strong evidence that the PAA helps understand dynamic changes of urban forest policy-making toward governance.     

Urban forest management in Addis Ababa,Ethiopia. A policy policy Arrangement Approach

Recently in Ethiopia, forest decline has been observed in every part of the country and identified as an important problem. However, studies on policy approaches are scarce, and thus policy change analysis is imperative for understanding urban forest management. This study aims at analyzing Ethiopian forest policies using a Policy Arrangement Approach (PAA) with four dimensions: discourse, actors, power and resources, and rules of the game. Policy changes during three regimes (Imperial, 1936–1974; Derg, 1974–1991; and the present government, 1991 to present) are analyzed. A qualitative research design was employed to obtain and analyze data. Our analysis has revealed that policy changes from government to governance with the government. This major turn reflects a fundamental shift in the dominant discourse about the management of forests. It is found that PAA is a useful analytical tool to understand and explain policy changes. Insights from this analysis can contribute to the design of an integrated urban forest policy and critically reflect the challenges and interventions needed to positively influence forest management.     

The routes to fruit: Governance of urban food trees in Canada

Interest in planting urban food trees (UFTs) in public spaces is growing in popularity as a form of urban greening and a potential food source. Currently there is minimal research on the governance and policy aspects of integrating food trees into cities. To fill this gap, we investigated the characteristics of UFT site governance and how it compares to current urban forest governance. Semi-structured interviews were conducted with relevant municipal officials in Calgary, Edmonton, Toronto and Victoria about their perspectives and involvement with UFT sites in their city. A scan of policy documents was completed to supplement the interviews. The interviews were analyzed using a deductive coding framework based on the Policy Arrangement Approach. We found that key actors at the UFT sites were local organizations and site champions, with minimal municipal engagement. Most site resources provided by municipalities were in-kind. There are also basic knowledge gaps about how to care for UFTs. Currently municipal by-laws prohibit the harvesting and removal of plant material, and are at odds with the purpose of UFT sites, with few municipalities fully integrating UFTs in policies. The primary discussion around UFTs centre concerns for public health and safety, management, and use of public space with limited discussions of benefits. This research demonstrates the value of co-governance models to support UFTs, while a shift in focus from risks to benefits could encourage additional resources and policy integration. Further, including UFTs into policy would also support foraging and food tree maintenance in public spaces, and more fully reflect the plurality of urban forest engagement.     

Drone remote sensing in urban forest management: A case study

We applied drone remote sensing to identify relationships between key forest health indicators collected in the field and four Vegetative Indices (VI) to improve conservation management of urban forests. Key indicators of urban forest health revealed several areas of conservation concern including a majority of overstory trees in moderate to severe decline, canopy gaps, anthropogenic dumping, vines overtaking the forest canopy, and invasion by non-native plant species. We found plot-level vegetation index (VI) values of NDVI, NDRE, GNDVI, and GRVI calculated from drone imagery are significantly related to the impact of several of these ecological concerns as well as metrics of forest composition and equitability. Despite the small number of plots, too few to provide a general predictive framework, these findings indicate a substantial potential for drone remote sensing as a low-cost, efficient tool for urban forest management. We discuss how our findings can advance urban forest management and discuss challenges and opportunities for future drone VI research in urban natural areas.     

Updating urban forest inventories: An example of the DISMUT model

Canberra is a unique city in Australia where the trees on public land that dominate the urban forest were planned for at the city's inception. In the mid-1990s, a 100% census of street and park trees was completed, and together with simple health, growth and yield models, this database formed the basis of a decision information system to support the management of the urban trees – DISMUT. The accuracy of the models was evaluated in a study in 2005 where models to predict total tree height were found to be unbiased and precise, tree crown dimension were under-estimated for small trees, and tree health was over-estimated. The over-estimate of health may be due to the relatively poor rainfall conditions over the past 10 years while the biases in crown dimension predictions are more likely due to a too simple model form. However, the existence of DISMUT predictions over all streets and parks in Canberra means that statistically efficient two-phase sampling approaches can be used to correct for any bias in the mean estimates of tree numbers and size, and also to predict the mean value of other environmental, economic or social parameters of interest that are correlated to tree size.     

Attitudes towards tree protections,development, and urban forest incentives among Florida (United States) residents

Tree ordinances can be an effective means of preserving urban forests in the face of development pressures. Despite this, they also have the potential to be divisive among the public - especially when applied to privately-owned land. In this study we surveyed 1716 Florida urban residents to understand how they value regulation and management of the urban forest. Specifically, we asked about: tree protection ordinances, incentive programs to manage or plant trees, justification for tree removal, and development. Most respondents supported tree protections, even when applied to trees on their own property or when they had the potential to limit development activities. Additionally, there was limited support for removing healthy trees for development. Respondents supported the use of funds for urban forestry efforts – particularly at the local or state level.     

Private residential urban forest structure and carbon storage in a moderate-sized urban area in the Midwest,United States

In conjunction with urbanization and its importance as a major driver of land-use change, increased efforts have been placed on understanding urban forests and the provisioning of ecosystem services. However, very little research has been conducted on private property and little is known about the structure and function of privately owned urban forests. This research examines the structure of and carbon storage services provided by private residential urban forests in a moderate-sized Midwestern city. The primary research questions are as follows: What is the structure of private urban forests, and how does it vary across parcels? How much carbon is stored in tree and soil pools of private urban forests, and how does carbon vary across parcels? Ecological inventories were conducted on 100 residential parcels within 14 Neighborhood and Homeowners Associations of varying size and development age. Tree species richness, diversity, density, and diameter distribution were determined on a per parcel basis and for the entire tree population sampled. Further, tree and soil carbon storage were determined for each parcel. Results of this research demonstrated large variability in per-parcel tree metrics. Twelve of the parcels sampled had two or fewer trees, while eleven had greater than 50 trees. Further, tree carbon storage ranged from no carbon to 11.22 kg C m^?2. Alternatively, soil carbon storage was less variable and averaged 4.7 kg C m^?2, approximately 1.9 times higher than the average carbon stored in trees (2.5 kg C m^?2). Management efforts aimed at maintaining or enhancing carbon storage and other ecosystem services should focus on both soil protection and maximizing services in living biomass. Our results demonstrate that sustaining tree-produced ecosystem services requires maintenance of large old trees and species diversity, not only in terms of relative abundance, but also relative dominance, and in combination, species–specific size distributions.     

Estimating the alignment of tree species composition with foraging practice in Philadelphia's urban forest: Toward a rapid assessment of provisioning services

Urban greenspaces (UGS) are increasingly recognized for their potential to provide provisioning services to residents foraging for food and other plant materials. The alignment of tree species composition with foraging practices in cities, and the provisioning services harvesters derive, in UGS remains less well studied. To address this gap, we draw on existing tree species data and forager practices in the City of Philadelphia to estimate the alignment between tree species composition and foraging in the city. Our approach uses an existing forest inventory, an international online database of useful species, online information for residents about useful species found in the city, and novel data about forager practices. By considering these datasets in tandem, we are able to identify useful tree species, species likely of interest to foragers, and species actively foraged, and estimate the relative abundance of species in each category. Our results suggest that managers may be able to analyze proxy data, through use of online quality ratings, to rapidly identify and assess forager interest in species found in their urban forests.     

Methods for the estimation of sampling sufficiency in urban forest inventories: The case of non-patterned compositions of trees on sidewalks

Sampling inventories are strategies to gather qualified information for managing urban forests, given the scarcity of budgetary resources for a complete inventory and lack of public engagement to reduce costs. However, procedures for testing sampling sufficiency can be unspecified in researches related to urban forest inventories and do not follow any specific pattern. Hence, to determine the sampling sufficiency, we tested different variables related to the trunk, crown, number of trees, and species, focusing on different aims of an inventory of trees on sidewalks. At a level of 10% of the total number of plots, each measuring 50.0 m × 3.0 m, we performed a stratified inventory of a city streetscape whose composition and quality represents most South American cities, with a non-patterned tree compostion. Sampling sufficiency was analyzed considering a limit of error of 10% and 15% by using 12 different variables. The stratification process was necessary for most of the variables analyzed (p > 0.01), with errors ranging from 5.87% to 15.28%. Sampling sufficiency was achieved for 10% of the total population of trees on sidewalks, at a 10% error limit for seven variables: diameter at breast height (DBH), cross-section area, crown diameter, crown area, number of species, and number of species per square meter of sidewalk and per kilometer of the street. However, this result was influenced by the variability of the variables used to estimate sampling sufficiency. As it is not possible to achieve different goals (tree registration, benefits, and diversity) with just one variable like the number of trees per kilometer of street, the sampling sufficiency estimation should be based on the use of at least the DBH, crown diameter, number of trees, and number of species. It would be a better strategy to ensure more reliable data estimations for sampling inventories of trees on sidewalks.     

Effects of patch size,isolation and regional abundance on forest bird communities

The aim of this study was to assess the impact of isolation on forest bird communities in agricultural landscapes in The Netherlands. We studied the avifauna of 235 small (0.1–39 ha) woodlots composed of mature deciduous trees in 1984–1985. These woodlots were selected in the eastern and central/southern part of the country within 22 regions showing great differences in landscape structure,i.e., degree of isolation. Multiple regression analysis indicated that woodlot size was the best single predictor of species number and probability of occurrence of most species. It turned out that the isolation variables, area of wood, number of woods, interpatch distance, and proximity and density of connecting elements, explained small but significant parts of the residual variances in species number. No single species was significantly affected by the density of connecting elements. Biogeographical differences between two groups of regions were emphasized. Evidence of four woodland species suggested that regional abundance affected the probability of occurrence in small isolates.     

Protest response and contingent valuation of an urban forest park in Fuzhou City,China

Urban forest parks, such as Fuzhou National Forest Park (FNFP), provide residents with landscape amenities, recreational opportunities, and interaction with nature. Understanding the recreational quality of green spaces and visitors’ behaviors and preferences is essential for effective forest park conservation strategy. We aimed to assess the recreational use and amenities of FNFP and calculate the monetary value of provided services using a contingent valuation method (CVM). A total of 249 park visitors were interviewed face-to-face based on a questionnaire using entrance fee as the payment vehicle, in October 2015 and January 2016. A considerable number of protest responses may cause selectivity bias; consequently, we used models excluding protest zeros. Sample selection models were estimated using Heckman’s two-step and full information maximum likelihood methods The average willingness-to-pay (WTP) was estimated to be 13.79 RMB (equivalent to 2.00 USD) for the unconditional model, and the lower mean values were estimated for two selectivity bias corrected models. In this case, park visitors would be willing to pay an average 11.6 RMB (equivalent to 1.69 USD) per person according to the full information maximum likelihood estimate and an average 10.96 RMB (equivalent to 1.60 USD) per person by the two-step method. Respondents’ satisfaction of forest park facilities and service significantly influenced their WTP value for forest park improvements. Socio-demographic features could not effectively discriminate the protest bidders and the other non-protest bidders. Our results suggest that protesters may value the resource less than positive bidders. The high percentage of protest respondents may be due to the current free use of FNFP and payment vehicle of entrance fee. The CVM approach takes residents’ preferences into consideration and allows the study of heterogenous socio-demographic groups; thus, our data may help to develop effective management plans for improving urban forest parks in China.     

Barriers to the effective planning and management of residential encroachment within urban forest edges: A Southern Ontario,Canada case study

Studies document degradation and loss of publicly owned urban woodland area following adjacent residential development due to residential encroachment. Residential encroachment is the negative impacts of housing land uses within both rural and urban green infrastructure networks. Prevailing planning, design and management approaches in Southern Ontario municipalities in Canada indicate planning and management tools have been developed to remove and impede encroachment impacts; however, many are infrequently implemented. This lack of implementation contributes to a high prevalence and spatial area of encroachment within Southern Ontario municipal woodland edges with adjacent housing. Long interviews were conducted with the planners, landscape architects, woodland managers and bylaw enforcement staff of six Southern Ontario municipalities to determine the barriers to implementation of municipal encroachment tools. Results indicate key barriers to policy implementation that reflect a lack of awareness of, and priority placed on addressing, residential encroachment impacts, and impacts following the point of development in general. Barriers include: (1) insufficient community and municipal access to information regarding residential encroachment and their significance relative to other development impacts; (2) lack of clarity of goals by municipalities and between departments; (3) insufficient municipal leadership and commitment to limiting encroachment; (4) lack of sufficient means within municipal departments to prevent and address encroachment; and (5) ineffectual dynamics of enforcement. Recommendations for overcoming barriers to the development and implementation of effective approaches for addressing encroachment are provided.     

The socioeconomics and management of Santiago de Chile''s public urban forests

Santiago, Chile's semi-arid climate and urbanized environment poses a severe limitation for the establishment and maintenance of urban forests. Municipalities, or comunas, are the main stakeholders in the management of Santiago's public urban forests. A tenable hypothesis would be that as the socioeconomic level of a comuna increases, the better the condition of a comuna's urban forest. Unfortunately, there is little comprehensive information on management, public expenditure, and structure of Santiago's public and private urban forests. To examine this hypothesis, Santiago was divided into socioeconomic strata, then using air photo interpretation and stratified field sampling, urban forest structures were quantified by socioeconomic strata. In addition, interview surveys were used to determine municipal urban forest management and expenditures for different public urban forests based on socioeconomic strata. Urban forests in the high socioeconomic strata had fewer public trees, greater tree cover, tree and leaf area density, and leaf area index than lower socioeconomic strata. The percentage of total municipal budget allocated to public urban forest management was consistent among strata, but the total public urban forest budgets were greater in the high socioeconomic strata. Public urban forest structure is related to the socioeconomic strata of Santiago's different comunas.     

The inequity of distribution of urban forest and ecosystem services in Cali,Colombia

Little is known about urban forest planning, management and its benefits in emerging countries. The uneven distribution of tree canopy cover and parks in urban area is related to environmental justice, especially with disadvantaged socio-economic and marginated communities. However, the inequity of urban forest in many cities of emerging countries where often found irregular and unregulated land use patterns and social and socio-economic inequities, is hardly highlighted. This study explores the inequity of distribution of tree canopy cover and public park in Cali, Colombia. Utilizing the traditional socio-economic indices, the stratification, linear regression analysis is conducted to describe relationship between total tree canopy cover, tree canopy cover of various land use types, number of parks and park area per capita. The result demonstrates that lower income communities have lower tree canopy cover, fewer parks and smaller park area than higher income communities. This paper discusses importance of accounting for urban forests and ecosystem service in city planning efforts and better strategies of reducing inequity in emerging countries. Addressing the inequity of urban forest could be a better strategy to create resilient, sustainable, safe and livable cities in emerging countries.     

The economic benefits and costs of trees in urban forest stewardship: A systematic review

Understanding the benefits provided by urban trees is important to justify investment and improve stewardship. Many studies have attempted to quantify the benefits of trees in monetary terms, though fewer have quantified the associated costs of planting and maintaining them. This systematic review examines the methods used to jointly analyse the costs and benefits of trees in the urban landscape, assesses the relative balance of benefits and costs, and attempts to understand the wide variation in economic values assigned in different studies. The benefits most frequently studied are those related to environmental regulation and property values, and the available data show that these usually outweigh the costs. Aesthetic, amenity, and shading benefits have also been shown to provide significant economic benefits, while benefits in terms of water regulation, carbon reduction and air quality are usually more modest. Variation in benefits and costs among studies is attributed largely to differences in the species composition and age structure of urban tree populations, though methodological differences also play a role. Comparison between studies is made difficult owing to differences in spatiotemporal scope, and in the way urban forest composition and demographic structure were reported. The overwhelming majority of studies concern deciduous trees in Northern America, and much less is known about urban forests in other regions, especially in the tropics. Future work should thus seek to fill these knowledge gaps, and standardise research protocols across cities. In light of ambitious goals in many cities to increase tree cover, ongoing advances in valuation methods need to provide a more comprehensive accounting of benefits and costs, and to better integrate economic assessment into the decision-making process.     

Exploring the characteristics of successful volunteer-led urban forest tree committees in Massachusetts

Citizen engagement through urban forest tree committee volunteer service may aid in providing essential experience, ideas, and skills that support municipal tree management. Using semi-structured, research interviews with tree committee (TC) representatives from across the Commonwealth of Massachusetts, this study addresses current knowledge gaps concerning the general composition, processes, and relationships of volunteer-led urban forest tree committees. Our findings indicate that TC representatives are typically motivated, passionate volunteers who generally desire to work cooperatively with the many associations, organizations, and agencies that comprise the local socio-political landscape. Our findings also indicate it is important that TC representatives make a sustained, concerted effort to work collaboratively with their local tree warden to advance the care of their community’s urban trees. Furthermore, it is also essential that municipal managers and decision-makers attempt to provide TC volunteers with appropriate training opportunities, resources, as well as demonstrate appreciation, to further encourage and solidify volunteer-engagement in urban forestry at the local level.     

Future climate risk and urban tree inventories in Australian cities: Pitfalls,possibilities and practical considerations

Urban tree inventories are useful tools to assess the environmental and socio-economic services provided by urban forests. These inventories enable the evaluation of the climate change risk to urban forests, and governments rely on such inventories for urban planning and management. Here, we assessed the future climate risk of Australia and the state of urban tree inventories across 116 local government areas (LGAs), representing 21 % of the country’s LGAs and encompassing 55 % of the national human population. We evaluated projected changes in temperature and precipitation by 2050 for each LGA and conducted a survey to obtain information on the extent and types of data available in existing urban tree inventories. Additionally, we compiled demographic, socio-economic, and geographical data for all LGAs to explore correlates with tree inventory status. Temperature increases in 2050 were predicted in all LGAs, with higher latitude and smaller LGAs identified to undergo greater increases in temperature compared to larger and lower latitude LGAs. Decreases in seasonal precipitation were predicted for 97 LGAs. Seventy-six (66 %) of surveyed LGAs had urban tree inventories, which most commonly included trees along streets and in parks. Sixty-one LGAs record information on tree mortality, while 31 LGAs dynamically update their inventories. The presence of an inventory and the area it covered were positively associated with human population density. More than 30 years ago, in 1988, John Gray wrote that “insufficient statistics were available in Australia to provide an accurate picture of the urban forest estate”. Our research shows there has not been a significant advance in the adoption and use of urban forest inventories over the past three decades. Long-term, dynamically updated inventories are crucial for urban forest management to inform planting choices to support sustainable and resilient cities.     

Role of social networks in urban forest management collaboration: A case study in northern Japan

Public participation is crucial for sustainable forest management. In particular, in urban forest areas, it is an important tool for overcoming conflicts among diverse needs regarding the forests through collaboration between citizens and governments. Such collaboration requires social learning. Social learning is dependent upon the presence of social networks that serve as an infrastructure for social capital. This study analyses the role of the social network in a participatory forest management approach of the Nopporo Forest Regeneration Project (NFRP) in the urban Nopporo National Forest in Hokkaido, northern Japan, aimed at restoring a typhoon damaged forest.Within the framework of the participatory approach the project hascreated a network of several citizen organizations for exchanging information. Outside this formal NFRP network several additional citizenorganizations are concerned about the Nopporo Forest management. The article describes the overall social network that has evolved around the Nopporo Forest and compares the attitudes and evaluations of the NFRP network organizations and the not formally NFRP related organizations towards their collaboration with government agencies and other citizen organizations. The overall social network around the Nopporo Forest had a multi-nodal character with the National Forest Agency and Hokkaido Prefectural Government acting as main central nodes. Only a few citizen organizations had direct relations to both central nodes; many organizations had links to either the National Forest Agency or the Prefectural Government. The organizations involved in the formal NFRP network had close ties with the National Forest Agency. This contributed to a positive evaluation of present forest management approach and the collaborative activities of the government agencies. In contrast, the organizations that were not involved in the formal NFRP network were found to have fewer ties with the National Forest Agency. The lack of opportunity to form a direct social learning relation hindered the formation of social capital and resulted in a lower evaluation of the participatory management approach as well as of the collaborative activities. Thus, although the participatory forest management approach of establishing formal social networks enhanced collaboration between the National Forest Agency and several citizen organizations and social learning, it was less successful in encouraging a democratic process involving all interested citizen organizations.     

Evaluating restoration success of a 40-year-old urban forest in reference to mature natural forest

We assessed whether forest restoration was successful in Expo ’70 Commemorative Park in Osaka Prefecture, Japan, which was planted in the 1970s with native late-successional tree species. Detailed survey and analysis of species composition, stand vertical stratification, and forest dynamics, including comparison with a reference, natural late-successional forest, were conducted. The restoration plots had grown to larger basal area compared with the reference plots, however, this was a consequence of very high densities of the overstory trees due to low self-thinning rate. Stand vertical structure of the restoration plots was biased toward overstory layers, causing high mortality of understory trees and shrubs. Because there are no mature forests near the restoration site that could act as a seed source, abundance and diversity of understory trees are likely to continue decreasing in the restoration plots, resulting in single-layered forest structure similar to those of monocultures and even-aged forests. Many seedlings of exotic species emerged in the restoration plots and this could lead to a plagiosere where exotic species dominate the vegetation inhibiting regeneration and growth of native species. Ordination analysis using different measures, basal area and abundance, showed apparently contradicting results, suggesting that multiple criteria are needed to evaluate forest restoration success. Our results indicate restoration of mature, late-successional forest cannot be achieved by simultaneous planting of native species. To sustain urban forests into the future, we must conduct long-term monitoring and management referencing natural forest structure and dynamics.