Pesticide treatments affect mountain pine beetle abundance and woodpecker foraging behavior.

In British Columbia, Canada, management efforts used to control mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreaks have included treatment of infested trees with an organic arsenic pesticide, monosodium methanearsonate (MSMA). Cumulative pesticide applications over a large geographic area have generated concerns about arsenic loading in the environment and potential toxicity to nontarget wildlife. We investigated woodpecker foraging patterns in infested stands with and without MSMA treatment using a combination of tree debarking indices, point count surveys, and radiotelemetry methods in addition to insect flight traps to measure mountain pine beetle emergence. Debarking indices indicated woodpecker foraging of MSMA-treated trees was significantly lower than nontreated trees in all sampling years. However, approximately 40% of MSMA trees had some evidence of foraging. Focal observations of foraging woodpeckers and point count surveys in MSMA treatment areas further confirmed that several species of woodpeckers regularly used MSMA stands during the breeding season. Radio-tagged Hairy (Picoides villosus) and Three-toed (Picoides dorsalis) Woodpeckers spent on average 13% and 23% (range 0-66%) of their time, respectively, in treated stands, despite the fact that these areas only comprised on average 1-2% of their core home range (1 km2). MSMA strongly reduced the emergence of several bark beetle (Coleoptera, Scolytidae) species including the mountain pine beetle, and there was a highly significant positive relationship between Dendroctonus beetle abundance and Three-toed Woodpecker abundance. This study identifies the potential negative impact that forest management practices using pesticides can have on woodpecker populations that depend on bark beetles and their host trees.     

A Heuristic Method for Determining Changes of Source Loads to Comply with Water Quality Limits in Catchments

A common land and water management task is to determine where and by how much source loadings need to change to meet water quality limits in receiving environments. This paper addresses the problem of quantifying changes in loading when limits are specified in many locations in a large and spatially heterogeneous catchment, accounting for cumulative downstream impacts. Current approaches to this problem tend to use either scenario analysis or optimization, which suffer from difficulties of generating scenarios that meet the limits, or high complexity of optimization approaches. In contrast, we present a novel method in which simple catchment models, load limits, upstream/downstream spatial relationships and spatial allocation rules are combined to arrive at source load changes. The process iteratively establishes the critical location (river segment or lake) where the limits are most constraining, and then adjusts sources upstream of the critical location to meet the limit at that location. The method is demonstrated with application to New Zealand (268,000 km2) for nutrients and the microbial indicator E. coli, which was conducted to support policy development regarding water quality limits. The model provided useful insights, such as a source load excess (the need for source load reduction) even after mitigation measures are introduced in order to comply with E. coli limits. On the other hand, there was headroom (ability to increase source loading) for nutrients. The method enables assessment of the necessary source load reductions to achieve water quality limits over broad areas such as large catchments or whole regions.     

Selenium speciation in wheat grain varies in the presence of nitrogen and sulphur fertilisers

This study investigated whether selenium species in wheat grains could be altered by exposure to different combinations of nitrogen (N) and sulphur (S) fertilisers in an agronomic biofortification experiment. Four Australian wheat cultivars (Mace, Janz, Emu Rock and Magenta) were grown in a glasshouse experiment and exposed to 3 mg Se kg^?1 soil as selenate (Se^VI). Plants were also exposed to 60 mg N kg^?1 soil as urea and 20 mg S kg^?1 soil as gypsum in a factorial design (N + S + Se; N + Se; S + Se; Se only). Plants were grown to maturity with grain analysed for total Se concentrations via ICP-MS and Se species determined via HPLC-ICP-MS. Grain Se concentrations ranged from 22 to 70 µg Se g^?1 grain (dry mass). Selenomethionine (SeMet), Se-methylselenocystine (MeSeCys), selenohomolanthionine (SeHLan), plus a large concentration of uncharacterised Se species were found in the extracts from grains. SeMet was the major Se species identified accounting for between 9 and 24 µg Se g^?1 grain. Exposure to different N and S fertiliser combinations altered the SeMet content of Mace, Janz and Emu Rock grain, but not that of Magenta. MeSeCys and SeHLan were found in far lower concentrations (<4 µg Se g^?1 grain). A large component of the total grain Se was uncharacterisable (>30 % of total grain Se) in all samples. When N fertiliser was applied (with or without S), the proportion of uncharacterisable Se increased between 60 and 70 % of the total grain Se. The data presented here indicate that it is possible to alter the content of individual Se species in wheat grains via biofortification combined with manipulation of N and S fertiliser regimes. This has potential significance in alleviating or combating both Se deficiency and Se toxicity effects in humans.     

Taking Environmental Action: The Role of Local Composition, Context, and Collective

This article explores individual and community action taken in response to perceived environmental risks by investigating the determinants of environmental action across a range of action types. A conceptual framework is first presented, which provides a foundation for investigating the role of local compositional (i.e., individual characteristics), contextual (i.e., neighborhood environment), and collective (i.e., social networks) factors in environmental action. To test the utility of the conceptual framework, a quantitative survey was administered to a random sample of households (n = 512) in Hamilton, Canada. The results suggest that the predictors of environmental action vary by action type (i.e., personal change, individual civic action, and cooperative civic action), and that factors related to perceived environmental exposure and social capital generally play a stronger, more consistent role in civic environmental action than sociodemographic or neighborhood factors. The results underscore the role of social connection in responses to perceived environmental risks.     

Country-level factors in a failing relationship with nature: Nature connectedness as a key metric for a sustainable future

Climate change and biodiversity loss show that the human–nature relationship is failing. That relationship can be measured through the construct of nature connectedness which is a key factor in pro-environmental behaviours and mental well-being. Country-level indicators of extinction of nature experience, consumption and commerce, use and control of nature and negativistic factors were selected. An exploratory analysis of the relationship between these metrics and nature connectedness across adult samples from 14 European countries was conducted (n = 14,745 respondents). The analysis provides insight into how affluence, technology and consumption are associated with the human–nature relationship. These findings motivate a comparison of how nature connectedness and composite indicators of prosperity, progress, development, and sustainability relate to indicators of human and nature’s well-being. In comparison to composite indexes, it is proposed that nature connectedness is a critical indicator of human and nature’s well-being needed to inform the transition to a sustainable future.     

Environmental accounting of natural capital and ecosystem services for the US National Forest System

The National Forests of the United States encompass 192.7?million acres (78?million hectares) of land, which is nearly five percent of the total land area of the nation. These lands are managed by the US Forest Service (USFS) for multiple uses, including extraction of timber, production of fossil fuels and minerals, public recreation, and the preservation of biodiversity, clean air, water, and soils. The USFS is interested in valuing the natural capital within, and the ecosystem services provided by, their lands. This is in part to justify expenditures in a time of limited resources. We used emergy and an environmental accounting approach, to quantify the ecosystem services, the exported environmental goods and information provided by National Forest System (NFS) lands, and the natural capital residing on those lands. Environmental accounting using emergy provides a method to value these flows of services and storages of capital using a common biophysical unit, the solar emjoule and its monetary equivalent the emdollar. We compare emdollar values to economic values gleaned from the literature. In 2005, the ecosystem services provided by USFS lands were equivalent to 197?billion emdollars, and the value of NFS natural capital was 24.3?trillion emdollars. Our evaluation suggests that the Federal Government budget allocation for the NFS ($5.55E+09 in 2005) was well spent, protecting 24.3?trillion emdollars in natural capital and insuring annual ecosystem services totaling 197?billion emdollars. Monetary values for some natural capital and ecosystem services are similar to emergy-derived values (resources like fish, wildlife, water, and firewood extracted from forests), and others are widely different (biodiversity, fossil, and mineral resources). There is large uncertainty associated with computing the environment’s contributions to society whether using emergy or accepted economic techniques; yet, the magnitude of these emergy-derived estimates suggests that even with the uncertainty, the values are significant and monetary expenditures for the Forest Service are justified.     

Physical modeling of the feedbacks between a patch of flexible Reed Canarygrass (Phalaris arundinacea), wake hydraulics,and downstream deposition

Environmental Fluid Mechanics - Reed Canarygrass (RCG) is an aggressive invader in aquatic ecosystems that swiftly modifies the environment, resulting in biodiversity loss and reduced flood...     

Organochlorines and eggshell thinning in northern gannets (Sula bassanus) from Eastern Canada, 1968-1984

The northern gannets (Sula bassanus) nesting on Bonaventure Island, Quebec, were studied from 1968 to 1984 in order to measure environmental contaminant levels and their relationship to productivity. Fresh eggs in 1969 contained a mean DDE level of 18.5 mg kg(-1) and had shells which were 17% thinner than pre-1947 samples. Unhatched eggs in 1969 had no outer calcified layer, a mean thickness 20% less than the pre-1947 mean, and mean DDE concentration of 30.6 mg kg(-1). Significantly higher levels of eight contaminants were measured in unhatched than in fresh eggs collected in 1969. DDE and shell thinning were also intercorrelated with nine other contaminants; these data strongly implicate toxic chemicals, particularly DDE, as the main cause for the low breeding success of Bonaventure gannets from 1966 to 1974. Extensive use of DDT to control forest insects around the Gulf of St Lawrence ceased in 1969. Use of DDT, dieldrin and PCBs was restricted in North America during the early 1970s. Residues of DDT, DDD, DDE, PCBs, dieldrin, HCB and chlordane-related compounds in gannet eggs decreased significantly during this study. Heptachlor epoxide remained constant while alpha-HCH appeared to increase. Estimated half-lives ranged from 3.1 years for DDD to 35.4 years for oxychlordane. The breeding success and population of the colony have coincidentally increased.