The influence of wind farm development on the hydrochemistry and ecology of an upland stream.

Despite perceptions of pristine condition, upland environments are increasingly subject to a range of anthropogenic pressures including air pollution, climate change, land-use change and evolving land management strategies. Although they have received little attention to date, the large-scale development of upland wind farms also has the potential to disturb vegetation and soils, alter hydrology and water quality and, thus, impact freshwater ecosystems. This paper presents the findings of a 5-year study of the impacts of wind farm construction on the freshwater environment. Data on water quality, invertebrate and fish populations were collected for 2 years before construction and for the following 3 years covering the construction period and the initial period of the farm's operation. In contrast to previous studies, the impacts of the wind farm development were assessed for a suite of potentially affected hydrochemical variables using a before-after-control-impact (BACI) analysis that allowed separation of construction effects from spatial and temporal variability in hydroclimatological conditions, thereby providing an improved, more robust evidence base. There was a small but significant negative effect of construction on pH, alkalinity (Alk) and acid neutralising capacity (ANC) in the upper part of the treatment catchment, which was where the wind farm was situated. The effects were more marked under higher flow conditions. It is hypothesised that this reflects changes in hydrological processes with increased near-surface runoff or organic acid mobilisation. There was no indication that either invertebrate community structure or fish densities were impacted by construction and the resulting effects on water quality.

Serum TIMP-1, TIMP-2, and MMP-1 in patients with systemic sclerosis, primary Raynaud's phenomenon, and in normal controls.

BACKGROUND: Excess tissue matrix accumulates in systemic sclerosis (SSc), accounting for both visceral and dermal fibrosis. It is suggested that decreased serum levels of matrix metalloproteinases (MMPs) or increased levels of tissue inhibitors of matrix metalloproteinases (TIMPs) may account for this matrix accumulation. OBJECTIVE: To measure serum levels of tissue inhibitors of metalloproteinases, TIMP-1, TIMP-2, and collagenase-1 (MMP-1), in patients with diffuse cutaneous systemic sclerosis (dcSSc), limited cutaneous systemic sclerosis (lcSSc), primary Raynaud's phenomenon (RP), and in normal controls. METHODS: Serum samples from patients with dcSSc (n=83), lcSSc (n=87), RP (n=80), and normal controls (n=98) were analysed using enzyme linked immunosorbent assays (ELISAs) for total TIMP-1, TIMP-2, and MMP-1. Results from each assay were analysed by the Kruskal-Wallis test. Dunn's multiple comparison post-test was then applied between groups. RESULTS: TIMP-1 levels were significantly raised in dcSSc and lcSSc groups compared with the RP group and normal controls (p<0.01 to p<0.001). In the dcSSc group, TIMP-1 levels were significantly higher in early disease (<2 years) than in late stage disease (>4 years) (p<0.05). This was not found for the lcSSc group. Serum TIMP-2 and MMP-1 levels in dcSSc and lcSSc did not differ significantly from those in normal controls. Increased levels of TIMPs were not convincingly associated with organ disease. No assay result correlated with autoantibody status (anti-topoisomerase 1 (anti-Scl-70), anticentromere antibody, or anti-RNA polymerase). No significant differences in serum TIMP-1, TIMP-2, or MMP-1 levels were shown in the RP group compared with normal controls. CONCLUSIONS: Raised TIMP-1 levels in the SSc groups support the hypothesis that matrix accumulation occurs in SSc at least in part owing to decreased degradation. Moreover, the variation in TIMP-1 levels between the early and late disease stages of dcSSc seems to reflect the early progressive course of dermal fibrosis seen clinically. The expected reduction in serum MMP-1 levels in the SSc groups was not found. This suggests that tissue matrix accumulation is due to increased inhibitors rather than to decreased MMPs.