Farm Boundary Survey and Study Block Establishment: A Set of Prior Activities For ACIAR/ASEM/053/2003 − Tree Measurement And Socio-Economic Survey

This paper discusses the method and process of conducting the perimeter survey of farms identified for the ACIAR Tree Farm project. There were two sets of information on existing tree farms used in identifying farms for the study − from the Department of Environment and Natural Resources (DENR) and Local Government Units (LGUs). Within a municipality, barangays with the greatest number of qualified tree farms were given priority for validation of farm area and number of trees. A courtesy appearance and discussion with LGU officers was always the first step to finding the tree farms. Being referred or accompanied by somebody, usually a barangay official, each qualified tree farmer was visited in their house. The decision to establish and number of tree blocks to consider in a farm was based on age of the plantation, area, species and species mixture, spacing, average size of trees, topography, slope, elevation, presence of vegetative cover particularly grasses and shrubs, soil characteristics, and evidence of silvicultural applications. Using a computer and the Mapsource program or Excel spreadsheet to create a sketch is quick and easy. However, the field team sometimes spent full weeks carrying out surveys, and tree farm sketches were needed for the socio-economic interviews and tree measurement in the same week. Sketches therefore were made manually either drawn to a scale or sometimes not. As soon as possible after the fieldwork, data from the GPS were downloaded to the Mapsource program on the computer. For every original set of data a revised version was created getting rid of the track logs and leaving only the waypoints and routes to emphasize the farm and block boundaries. For future use, the original GPS data were retained

Improving the triple bottom line returns from smallholder tree farms in the Philippines: A systems approach

This paper outlines the application of Systems Thinking in investigating ways to improve the returns to smallholder tree farmers in the Philippines. The paper illustrates how a systems approach was used in the conceptualisation of the project and how systems thinking facilitated a shared understanding of the how each individual’s research contributed to the broader project activities. Systems Thinking has also been used in the design and implementation of various project activities. Three examples are provided. The first example illustrates how a systems diagram was developed which outlined the direct and indirect linkages between biophysical data on tree farms and various activities designed to increase returns. The second example illustrates how the suggested approach for improving the flow of information concerning tree registration, harvest and transportation regulations and approval mechanisms link with various project activities and have been informed by a series of action research workshops. The third example illustrates how systems thinking has also been applied to understand the factors affecting the production of high quality tree seedlings and to investigate the effect of policy interventions on improving the quality of seedlings available to smallholders

Usefulness of fair valuation of biological assets for cash flow prediction

This study develops an empirical analysis of the relevance of accounting information when biological assets are measured at fair value. We use an international sample of firms with biological assets.We find that biological assets influence unpredictability when they are measured at historical cost (HC). In this case, the ability of accounting data to predict future cash flows diminishes as the proportion of biological assets on total assets increases. The valuation at fair value (FV) switches this negative influence of biological assets to a positive one. We find that when they are measured at FV, the prediction accuracy of future cash flows improves as the ratio of biological assets to total assets increases. This evidence is robust to differentmeasures of prediction accuracy, as well as to the improvement of accounting standards, regardless of FV, over time. The evidence is weaker for bearer plants

Understandings of sustainable corporate governance by Australian managed investment schemes and some implications for small-scale forestry in Australia

This study reveals that managers of Australian managed investment schemes understand sustainable corporate governance as a mix of financial, natural environment and social outcomes. The managers that were interviewed prioritized financial aspects of business performance but acknowledged that sustained financial performance was only possible if positive natural environment outcomes and positive social outcomes were also sustained. In this context, the managers expressed qualified support for the development of small-scale forestry in Australia

Landholder Typologies Used in the Development of Natural Resource Management Programs in Australia - A Review

This article reviews the literature on the identification of landholder typologies that can be used to assist the design and delivery of natural resource management (NRM) programs. Australian researchers have developed typologies of landholders based on a variety of criteria. The rationale for developing landholder typologies is first discussed before reviewing the various approaches that have been used by Australian researchers and comparing their findings. The methods employed have differed according to the theories used to guide the research and the 'clients' or 'sponsors' of the research. The landholder types they describe, however, have a number of similarities. These similarities suggest that the studies have identified the same fundamental divisions in the rural community, and that it may be possible to integrate landholder typologies for a variety of NRM and non-NRM applications. It is concluded that further research could usefully investigate whether concepts of social class or sub-cultures may be appropriate to define and describe the variations in landholder types

Evenness mediates the global relationship between forest productivity and richness

1. Biodiversity is an important component of natural ecosystems, with higher species richness often correlating with an increase in ecosystem productivity. Yet, this relationship varies substantially across environments, typically becoming less pronounced at high levels of species richness. However, species richness alone cannot reflect all important properties of a community, including community evenness, which may mediate the relationship between biodiversity and productivity. If the evenness of a community correlates negatively with richness across forests globally, then a greater number of species may not always increase overall diversity and productivity of the system. Theoretical work and local empirical studies have shown that the effect of evenness on ecosystem functioning may be especially strong at high richness levels, yet the consistency of this remains untested at a global scale. 2. Here, we used a dataset of forests from across the globe, which includes composition, biomass accumulation and net primary productivity, to explore whether productivity correlates with community evenness and richness in a way that evenness appears to buffer the effect of richness. Specifically, we evaluated whether low levels of evenness in speciose communities correlate with the attenuation of the richness–productivity relationship. 3. We found that tree species richness and evenness are negatively correlated across forests globally, with highly speciose forests typically comprising a few dominant and many rare species. Furthermore, we found that the correlation between diversity and productivity changes with evenness: at low richness, uneven communities are more productive, while at high richness, even communities are more productive. 4. Synthesis. Collectively, these results demonstrate that evenness is an integral component of the relationship between biodiversity and productivity, and that the attenuating effect of richness on forest productivity might be partly explained by low evenness in speciose communities. Productivity generally increases with species richness, until reduced evenness limits the overall increases in community diversity. Our research suggests that evenness is a fundamental component of biodiversity–ecosystem function relationships, and is of critical importance for guiding conservation and sustainable ecosystem management decisions

Climatic controls of decomposition drive the global biogeography of forest-tree symbioses

The identity of the dominant root-associated microbial symbionts in a forest determines the ability of trees to access limiting nutrients from atmospheric or soil pools1,2, sequester carbon3,4 and withstand the effects of climate change5,6. Characterizing the global distribution of these symbioses and identifying the factors that control this distribution are thus integral to understanding the present and future functioning of forest ecosystems. Here we generate a spatially explicit global map of the symbiotic status of forests, using a database of over 1.1 million forest inventory plots that collectively contain over 28,000 tree species. Our analyses indicate that climate variables—in particular, climatically controlled variation in the rate of decomposition—are the primary drivers of the global distribution of major symbioses. We estimate that ectomycorrhizal trees, which represent only 2% of all plant species7, constitute approximately 60% of tree stems on Earth. Ectomycorrhizal symbiosis dominates forests in which seasonally cold and dry climates inhibit decomposition, and is the predominant form of symbiosis at high latitudes and elevation. By contrast, arbuscular mycorrhizal trees dominate in aseasonal, warm tropical forests, and occur with ectomycorrhizal trees in temperate biomes in which seasonally warm-and-wet climates enhance decomposition. Continental transitions between forests dominated by ectomycorrhizal or arbuscular mycorrhizal trees occur relatively abruptly along climate-driven decomposition gradients; these transitions are probably caused by positive feedback effects between plants and microorganisms. Symbiotic nitrogen fixers—which are insensitive to climatic controls on decomposition (compared with mycorrhizal fungi)—are most abundant in arid biomes with alkaline soils and high maximum temperatures. The climatically driven global symbiosis gradient that we document provides a spatially explicit quantitative understanding of microbial symbioses at the global scale, and demonstrates the critical role of microbial mutualisms in shaping the distribution of plant species

Native diversity buffers against severity of non-native tree invasions

Determining the drivers of non-native plant invasions is critical for managing native ecosystems and limiting the spread of invasive species$^{1,2}$. Tree invasions in particular have been relatively overlooked, even though they have the potential to transform ecosystems and economies$^{3,4}$. Here, leveraging global tree databases$^{5,6,7}$, we explore how the phylogenetic and functional diversity of native tree communities, human pressure and the environment influence the establishment of non-native tree species and the subsequent invasion severity. We find that anthropogenic factors are key to predicting whether a location is invaded, but that invasion severity is underpinned by native diversity, with higher diversity predicting lower invasion severity. Temperature and precipitation emerge as strong predictors of invasion strategy, with non-native species invading successfully when they are similar to the native community in cold or dry extremes. Yet, despite the influence of these ecological forces in determining invasion strategy, we find evidence that these patterns can be obscured by human activity, with lower ecological signal in areas with higher proximity to shipping ports. Our global perspective of non-native tree invasion highlights that human drivers influence non-native tree presence, and that native phylogenetic and functional diversity have a critical role in the establishment and spread of subsequent invasions

Evenness mediates the global relationship between forest productivity and richness

1. Biodiversity is an important component of natural ecosystems, with higher species richness often correlating with an increase in ecosystem productivity. Yet, this relationship varies substantially across environments, typically becoming less pronounced at high levels of species richness. However, species richness alone cannot reflect all important properties of a community, including community evenness, which may mediate the relationship between biodiversity and productivity. If the evenness of a community correlates negatively with richness across forests globally, then a greater number of species may not always increase overall diversity and productivity of the system. Theoretical work and local empirical studies have shown that the effect of evenness on ecosystem functioning may be especially strong at high richness levels, yet the consistency of this remains untested at a global scale. 2. Here, we used a dataset of forests from across the globe, which includes composition, biomass accumulation and net primary productivity, to explore whether productivity correlates with community evenness and richness in a way that evenness appears to buffer the effect of richness. Specifically, we evaluated whether low levels of evenness in speciose communities correlate with the attenuation of the richness–productivity relationship. 3. We found that tree species richness and evenness are negatively correlated across forests globally, with highly speciose forests typically comprising a few dominant and many rare species. Furthermore, we found that the correlation between diversity and productivity changes with evenness: at low richness, uneven communities are more productive, while at high richness, even communities are more productive. 4. Synthesis. Collectively, these results demonstrate that evenness is an integral component of the relationship between biodiversity and productivity, and that the attenuating effect of richness on forest productivity might be partly explained by low evenness in speciose communities. Productivity generally increases with species richness, until reduced evenness limits the overall increases in community diversity. Our research suggests that evenness is a fundamental component of biodiversity–ecosystem function relationships, and is of critical importance for guiding conservation and sustainable ecosystem management decisions