Long-term nutrient addition increased CH4 emission from a bog through direct and indirect effects.

Peatlands are globally significant sources of atmospheric methane (CH4). While several studies have examined the effects of nutrient addition on CH4 dynamics, there are few long-term peatland fertilization experiments, which are needed to understand the aggregated effects of nutrient deposition on ecosystem functioning. We investigated responses of CH4 flux and production to long-term field treatments with three levels of N (1.6-6.4 g m-2 yr-1 as NH4NO3), potassium and phosphorus (PK, 5.0 g P and 6.3 g K m-2 yr-1 as KH2PO4), and NPK in a temperate bog. Methane fluxes were measured in the field from May to August in 2005 and 2015. In 2015 CH4 flux was higher in the NPK treatment with 16 years of 6.4 g N m-2 yr-1 than in the control (50.5 vs. 8.6 mg CH4 m-2 d-1). The increase in CH4 flux was associated with wetter conditions derived from peat subsidence. Incubation of peat samples, with and without short-term PK amendment, showed that potential CH4 production was enhanced in the PK treatments, both from field application and by amending the incubation. We suggest that changes in this bog ecosystem originate from long-term vegetation change, increased decomposition and direct nutrient effects on microbial dynamics.

Nutrient resorption of two evergreen shrubs in response to long­term fertilization in a bog.

Plant resorption of multiple nutrients during leaf senescence has been established but stoichiometric changes among N, P and K during resorption and after fertilization are poorly understood. We anticipated that increased N supply would lead to further P limitation or co-limitation with N or K [i.e. P-(co)limitation], decrease N resorption and increase P and K resorption, while P and K addition would decrease P and K resorption and increase N resorption. Furthermore, Ca would accumulate while Mg would be resorbed during leaf senescence, irrespective of fertilization. We investigated the effect of N, P and K addition on resorption in two evergreen shrubs (Chamaedaphne calyculata and Rhododendron groenlandicum) in a long-term fertilization experiment at Mer Bleue bog, Ontario, Canada. In general, N addition caused further P-(co)limitation, increased P and K resorption efficiency but did not affect N resorption. P and K addition did not shift the system to N limitation and affect K resorption, but reduced P resorption proficiency. C. calyculata resorbed both Ca and Mg while R. groenlandicum resorbed neither. C. calyculata showed a higher resorption than R. groenlandicum, suggesting it is better adapted to nutrient deficiency than R. groenlandicum. Resorption during leaf senescence decreased N:P, N:K and K:P ratios. The limited response of N and K and the response of P resorption to fertilization reflect the stoichiometric coupling of nutrient cycling, which varies among the two shrub species; changes in species composition may affect nutrient cycling in bogs.

Vegetation feedbacks of nutrient addition lead to a weaker carbon sink in an ombrotrophic bog.

To study vegetation feedbacks of nutrient addition on carbon sequestration capacity, we investigated vegetation and ecosystem CO2 exchange at Mer Bleue Bog, Canada in plots that had been fertilized with nitrogen (N) or with N plus phosphorus (P) and potassium (K) for 7-12 years. Gross photosynthesis, ecosystem respiration, and net CO2 exchange were measured weekly during May-September 2011 using climate-controlled chambers. A substrate-induced respiration technique was used to determine the functional ability of the microbial community. The highest N and NPK additions were associated with 40% less net CO2 uptake than the control. In the NPK additions, a diminished C sink potential was due to a 20-30% increase in ecosystem respiration, while gross photosynthesis rates did not change as greater vascular plant biomass compensated for the decrease in Sphagnum mosses. In the highest N-only treatment, small reductions in gross photosynthesis and no change in ecosystem respiration led to the reduced C sink. Substrate-induced microbial respiration was significantly higher in all levels of NPK additions compared with control. The temperature sensitivity of respiration in the plots was lower with increasing cumulative N load, suggesting more labile sources of respired CO2 . The weaker C sink potential could be explained by changes in nutrient availability, higher woody : foliar ratio, moss loss, and enhanced decomposition. Stronger responses to NPK fertilization than to N-only fertilization for both shrub biomass production and decomposition suggest that the bog ecosystem is N-P/K colimited rather than N-limited. Negative effects of further N-only deposition were indicated by delayed spring CO2 uptake. In contrast to forests, increased wood formation and surface litter accumulation in bogs seem to reduce the C sink potential owing to the loss of peat-forming Sphagnum.

Litter decomposition and nitrogen and phosphorus dynamics in peatlands and uplands over 12 years in central Canada.

The large accumulation of organic matter in peatlands has been partially attributed to litter decomposition rates, which are slowed by a high water table. To test this, we examined whether there were significant differences in the decomposition and N and P dynamics of ten foliar litters and wood blocks at three pairs of upland forest and peatland sites in the transitional grassland, high boreal and low subarctic regions of central Canada, using litterbags collected over a 12-year period. At two of the three pairs, the decomposition rate, as determined by proportion of the original mass remaining after 12 years and by the exponential decay coefficient (k), was faster overall at the upland than at the peatland. In the third pair, there was no significant difference, despite the water table being close to the peat surface; warmer soil temperatures in the peatland than the upland may be the cause. In general, there were small losses or gains of N in the litters after 12 years, compared to the original litter, though there were some differences among litter types and sites, net gains in N likely reflecting the higher exogenous N availability. P was lost from most litters at the two northern pairs of sites, but at the transitional grassland pair, there were large net gains in P and greater variation among litters. The N:P ratio in the original litters ranged from 5 to 26 and after 12 years the ratio narrowed, with the site average of the ten litters ranging from 13 to 22, varying with the soil ratio. Decomposition rates and N and P dynamics after 12 years are different between upland and peatland sites: although the water table is a primary control on these differences, other factors such as temperature and soil nutrient status are also important.

We're all in it together: supporting young carers and their families in Australia.

Although recent initiatives in Australia have attempted to respond to the needs of children and young people with care responsibilities, many continue to be unable to access responsive supports. A qualitative, exploratory study was conducted to identify the current needs and barriers to services for young carers and their families in Canberra, Australia. This paper focuses on a range of family, service and systems level issues that impede young carers' access to services. The findings are based on semistructured, face-to-face interviews conducted with 50 children and young people with care responsibilities. Purposive and snowballing sampling were used to recruit the sample. Peer researchers were involved in the development of the research parameters and conducted and analysed interviews. Young carers in this sample reported high levels of need but low levels of support provided formally and informally by their extended families and the service sector. Major barriers to support included reluctance within families to seek assistance for fear of child removal, negative intervention and increased scrutiny; the families' lack of awareness of available services; a lack of flexibility and responsiveness to the holistic needs of families; and a lack of service collaboration. The importance of recognising the specific needs of each member within the family unit was particularly highlighted as was the need for responsive and co-ordinated service supports.

The efficacy of oral nonsteroidal anti-inflammatory medication (NSAID) in the treatment of plantar fasciitis: a randomized, prospective, placebo-controlled study.

BACKGROUND: Plantar fasciitis frequently responds to a broad range of conservative therapies, and there is no single universally accepted way of treating this condition. Modalities commonly used include rest, ice massage, stretching of the Achilles tendon and plantar fascia, nonsteroidal anti-inflammatory medications (NSAIDs), corticosteroid injections, foot padding, taping, shoe modifications (steel shank and anterior rocker bottom), arch supports, heel cups, custom foot orthoses, night splints, ultrasound, and casting. To our knowledge, no prospective, randomized, placebo controlled double-blind study has evaluated the efficacy of oral NSAIDs in the treatment of plantar fasciitis. METHODS: Twenty-nine patients with the diagnosis of plantar fasciitis were treated with a conservative regimen that included heel-cord stretching, viscoelastic heel cups, and night splinting. They were randomly assigned to either a placebo group or an NSAID group. In the NSAID group, celecoxib was added to the treatment regimen. RESULTS: Pain and disability mean scores improved significantly over time in both groups, although there was no statistical significance between the placebo and NSAID groups at 1, 2, or 6 months. There was a trend towards improved pain relief and disability in the NSAID group, especially in the interval between the 2 and 6-month followup. Pain improved from baseline to 6 months by a factor of 5.2 and disability by 3.8 in the NSAID group compared to 3.6 and 3.5, respectively, in the placebo group. Even though at baseline the pain and disability scores were higher in the NSAID group, the final pain and disability scores were subjectively lower in the NSAID group than in the placebo group (1.43 for pain and 1.16 for disability in the NSAID group, compared to 1.86 and 1.49, respectively, in the placebo group). CONCLUSIONS: These results provide some evidence that the use of an NSAID may increase pain relief and decrease disability in patients with plantar fasciitis when used with a conservative treatment regimen.

The neurobehavioral effects of phytoestrogens in male Syrian hamsters.

We used a phytoestrogen (PE) and a phytoestrogen-free (PE-Free) diet to determine whether or not diet can have neurobehavioral effects on intermale aggression in Syrian hamsters (Mesocricetus auratus). In Experiment 1, 20 adult male hamsters were pre-tested for aggression and then placed on a PE (n=10) or a PE-Free diet (n=10) for 4 weeks in isolation. During week 5, experimental hamsters were exposed to a group-housed, nonaggressive opponent (NAO) for 5 min in a neutral cage arena. PE-fed hamsters exhibited more attacks (33.4+/-6.1) toward the NAO compared to the PE-Free-fed hamsters (18.1+/-4) (p<0.05). Interestingly, testosterone in the blood serum was higher in the PE-fed group (11.01+/-1.48 ng/ml) compared to the PE-Free group (6.5+/-0.87 ng/ml). In Experiment 2, 16 juvenile hamsters were weaned onto a PE (n=8) or a PE-Free diet (n=8). After 7 weeks on the diet, experimental hamsters were exposed to a NAO for 5 min in a neutral cage arena. Although the PE group exhibited higher levels of aggressive behavior, there were no statistically significant differences between groups. However, the PE group had higher levels of testosterone (9.0+/-0.95 ng/ml) compared to the PE-Free group (4.6+/-0.98 ng/ml) (p<0.05). In addition, analysis of the brains from both experiments revealed differences in binding for vasopressin 1A (V1A) receptors. Optical densities were converted to disintegrating units per min/mg. The PE-Free group had higher levels of V1A receptor binding (2689.93+/-254.8 dpm/mg) compared to the PE group (1907.32+/-136.3 dpm/mg) in the lateral septum (p<0.05). In addition, there were differences in the lateral hypothalamus, but the PE group had higher receptor binding (2550.9+/-63.59 dpm/mg) when compared to the PE-Free group (2011.9+/-174.14 dpm/mg) (p<0.05). In sum, these data present the first evidence that phytoestrogens can affect aggressive behavior and, concurrently, alter hormonal status and stimulate changes in the brain of male hamsters.