Modelling the Choice Between Multiple-Use vs. Specialised Forest Management and its Impact on Forest Management Costs

Forests provide ecosystem services, including timber production. In some cases, private forest owners perform management actions in order to enhance the provision of such services, or they may be encouraged by public policies and payments. This paper focuses specifically on the decision to set forest land aside for biodiversity conservation, as part of the more general question of the efficiency of multiple-use vs. specialised management of forest lands. We propose an econometric analysis to identify factors in the set-aside choice and measure the impact of this decision on forest management costs. The results show that the set-aside choice depends on the landowners’ income and motivations related to forest amenities. The choice of specialised management, as reflected in the set-aside decision, has a significant and positive impact on the intensity of management in the remainder of the forest and on management costs. From a policy implications point of view, these results suggest that instruments such as forest certification, subsidies and reverse auctions for conservation will be most likely to attract the interest of those forest owners with personal motivations and forest properties that offer both benefit and cost advantages in opting for such specialised management strategies.

     

Trends in anecdotal fox sightings in Tasmania accounted for by psychological factors

There has been little evaluation of anecdotal sightings as a means to confirm new incursions of invasive species. This paper explores the potential for equivocal information communicated by the media to account for patterns of anecdotal reports. In 2001, it was widely reported that red foxes (Vulpes vulpes) had been deliberately released in the island state of Tasmania (Australia), although this claim was later revealed to be baseless. Regardless, by 2013 a total of 3153 anecdotal fox sightings had been reported by members of the public, which implied their distribution was wide. For each month in 2001–2003, we defined a monthly media index (MMI) of fox‐related media coverage, an index of their relative seasonal abundance (abundance), and a factor denoting claims of fox evidence (claimed evidence) regardless of its evidentiary quality. We fitted a generalized linear model with Poisson error for monthly totals of anecdotal sightings with factors of year and claimed evidence and covariates of MMI, abundance, and hours of darkness. The collective effect of psychological factors (MMI, claimed evidence, and year) relative to biophysical factors (photoperiod and abundance) was highly significant (χ² = 122.1, df = 6, p < 0.0001), whereas anticipated changes in abundance had no significant influence on reported sightings (p = 0.15). An annual index of fox media from 2001 to 2010 was strongly associated with the yearly tally of anecdotal sightings (p = 0.018). The odds ratio of sightings ranked as reliable by the fox eradication program in any year decreased exponentially at a rate of 0.00643 as the total number of sightings increased (p < 0.0001) and was indicative of an observer‐expectancy bias. Our results suggest anecdotal sightings are highly susceptible to cognitive biases and when used to qualify and quantify species presence can contribute to flawed risk assessments.     

Environmental monitoring of water resources around a municipal landfill of the Rio Grande do Sul state,Brazil

Environmental Science and Pollution Research - In Brazil, landfills are commonly used as a method for the final disposal of waste that is compliant with the legislation. This technique, however,...     

Modeling the Impacts of Two Bark Beetle Species Under a Warming Climate in the Southwestern USA: Ecological and Economic Consequences

Predicted climate warming is expected to have profound effects on bark beetle population dynamics in the southwestern United States. Temperature-mediated effects may include increases in developmental rates, generations per year, and changes in habitat suitability. As a result, the impacts of Dendroctonus frontalis and Dendroctonus mexicanus on forest resources are likely subject to amplification. To assess the implications of such change, we evaluated the generations per year of these species under three climate scenarios using a degree-day development model. We also assessed economic impacts of increased beetle outbreaks in terms of the costs of application of preventative silvicultural treatments and potential economic revenues forgone. Across the southwestern USA, the potential number of beetle generations per year ranged from 1–3+ under historical climate, an increase of 2–4+ under the minimal warming scenario and 3–5+ under the greatest warming scenario. Economic benefits of applying basal area reduction treatments to reduce forest susceptibility to beetle outbreaks ranged from 7.75/ha (NM) to7.75/ha (NM) to 95.69/ha (AZ) under historical conditions, and 47.96/ha (NM) to47.96/ha (NM) to 174.58/ha (AZ) under simulated severe drought conditions. Basal area reduction treatments that reduce forest susceptibility to beetle outbreak result in higher net present values than no action scenarios. Coupled with other deleterious consequences associated with beetle outbreaks, such as increased wildfires, the results suggest that forest thinning treatments play a useful role in a period of climate warming.     

Fish reintroductions reveal smooth transitions between lake community states

Whether communities respond smoothly or discontinuously to changing environmental conditions has important consequences for the preservation and restoration of ecosystems. Theory shows that communities may exhibit a variety of responses to environmental change, including abrupt transitions due to the existence of alternate states. However, there have been few opportunities to look for such transitions in nature. Here, we examine the impact of a two-orders-of-magnitude decrease and then increase in planktivore abundance in Wintergreen lake (Michigan, USA), caused by the extinction and reintroduction of two dominant fish species (largemouth bass, Micropterus salmoides, and bluegill, Lepomis macrochirus). Over a 16 + yr period of slow change from high planktivory to low planktivory back to high planktivory, the zooplankton community changed smoothly and predictably between states. In years of low planktivory, the zooplankton assemblage was dominated by a single, large, cladoceran species, Daphnia pulicaria, whereas in years of high planktivory, D. pulicaria disappeared and was replaced by a suite of small-bodied cladocerans. We quantified the multivariate change in zooplankton community dissimilarity and found that community state smoothly tracked changes in planktivore density in both a forward and backward direction. Thus, there was little evidence of discontinuity in this system where transitions are strongly driven by planktivory.     

Forest service experience with interdisciplinary teams developing integrated resource management plans

The National Forest Management Act and National Environmental Policy Act require the use of an interdisciplinary team (ID team) to do integrated resource planning for the National Forests and the concurrent environmental analysis. A survey sent to all National Forest planning officers (82% response) reveals the composition of the ID teams used in integrated resource and land management planning. More than half the National Forests ID teams met NEPA and NFMA compositional requirements. National Forest planners recount their experiences with these ID teams. Despite frustrations with many aspects of the ID teams, the planners strongly support the idea that ID teams are an important part of the land-use planning process and think that their use leads to better National Forest integrated resource plans.     

Development of a Model for Simulation of Solute Transport in a Stream–Aquifer System

A model for simulation of solute transport in a dynamic stream–aquifer system is developed by integrating four existing sub-models. Interface packages are created to link the sub-models. The developed model is successfully used to simulate chloride transport in the stream–aquifer system of the Arkansas River and the Equus Beds Aquifer in Kansas and demonstrates that chloride concentration in the aquifer decreases in the vicinity of the simulated channel over time.     

Sleeping with a broken promise: The moderating role of generativity concerns in the relationship between psychological contract breach and insomnia among older workers

This paper examines the relationship between psychological contract breach and insomnia among older workers (aged 40 years and up). Drawing upon the conservation of resources theory, we conceptualize breach as a stressful event characterized by a perceived threat, failure to gain, or actual loss of valued resources, which increases psychological distress and insomnia. Moreover, we hypothesized that older workers' generativity concerns would act as a personal resource that would buffer the negative impact of breach. We tested our proposed model in 2 studies (Study 1 = 123; Study 2 = 168) of employee–spouse dyads. Results revealed that psychological distress mediated the relationship between psychological contract breach and insomnia. These mediated relationships were significant for those with low, but not for those with high levels of generativity concerns. These effects remained significant even after controlling for perceived organizational support (i.e., a social exchange mechanism). Theoretical and practical implications are discussed.