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Wheat is a crop of global importance that supplies carbohydrates to more than half of the worlds’ population. We examined whether climate change-induced rainfall patterns, which are expected to produce less frequent but heavier rain events, will alter the productivity of wheat and agroecosystem functioning on three different soil types. Therefore, in a full-factorial experiment, Triticum aestivum L. was cultivated in 3-m2 lysimeter plots, each of which contained one of the following soil types: sandy calcaric phaeozem, gleyic phaeozem and calcic chernozem. Predicted rainfall patterns based on the calculations of a regionalised climate change model were compared with the current long-term rainfall patterns, and each treatment combination was replicated three times. Future rainfall patterns significantly reduced wheat yield, leaf area index, and plant height at the earlier growth stages; it equally decreased the arbuscular mycorrhizal fungi colonisation of roots and increased the stable carbon isotope signature (δ13C) of wheat leaves. Sandy soils with inherently lower mineralization potential negatively affected wheat growth, harvest index, and yield but stimulated early season root production. The interaction between rainfall and soil type was significant for the harvest index and early wheat development. Our results suggest that changes in rainfall intensity and frequency can significantly affect the functioning of wheat agroecosystems. Wheat production under future rainfall conditions will likely become more challenging as further concurrent climate change factors become prevalent.

BackgroundGlyphosate-based herbicides are the most widely used pesticides in agriculture, horticulture, municipalities and private gardens that can potentially contaminate nearby water bodies inhabited by amphibians and algae. Moreover, the development and diversity of these aquatic organisms could also be affected by human-induced climate change that might lead to more periods with extreme temperatures. However, to what extent non-target effects of these herbicides on amphibians or algae are altered by varying temperature is not well known.MethodsWe studied effects of five concentrations of the glyphosate-based herbicide formulation Roundup PowerFlex (0, 1.5, 3, 4 mg acid equivalent glyphosate L−1as a one time addition and a pulse treatment of totally 4 mg a.e. glyphosate L−1) on larval development of Common toads (Bufo bufo, L.; Amphibia: Anura) and associated algae communities under two temperature regimes (15 vs. 20 °C).ResultsHerbicide contamination reduced tail growth (−8%), induced the occurrence of tail deformations (i.e. lacerated or crooked tails) and reduced algae diversity (−6%). Higher water temperature increased tadpole growth (tail and body length (tl/bl) +66%, length-to-width ratio +4%) and decreased algae diversity (−21%). No clear relation between herbicide concentrations and tadpole growth or algae density or diversity was observed. Interactive effects of herbicides and temperature affected growth parameters, tail deformation and tadpole mortality indicating that the herbicide effects are temperature-dependent. Remarkably, herbicide-temperature interactions resulted in deformed tails in 34% of all herbicide treated tadpoles at 15 °C whereas no tail deformations were observed for the herbicide-free control at 15 °C or any tadpole at 20 °C; herbicide-induced mortality was higher at 15 °C but lower at 20 °C.DiscussionThese herbicide- and temperature-induced changes may have decided effects on ecological interactions in freshwater ecosystems. Although no clear dose-response effect was seen, the presence of glyphosate was decisive for an effect, suggesting that the lowest observed effect concentration (LOEC) in our study was 1.5 mg a.e. glyphosate L−1water. Overall, our findings also question the relevance of pesticide risk assessments conducted at standard temperatures.

Glyphosate-based herbicide formulations are broadly used in agriculture, silviculture, horticulture as well as in private gardens all over the world, thus posing the risk of potential contamination of nearby aquatic bodies inhabited by amphibians. Concurrently, climate change can be expected to alter the temperature of amphibian breeding sites. However, while either glyphosate-based herbicides or temperature have been shown to separately affect the development of amphibians, very little is known on possible interactive effects. We studied the impact of herbicide concentrations and temperature on growth and development of eggs and tadpoles of the Common toad (Bufo bufo L.). We hypothesized that (i) eggs would be better protected against herbicides than tadpoles because of their jelly coating, (ii) that higher temperatures would reduce potential herbicide effects because of an accelerated growth and a lower sensitivity of larger specimens. We conducted one experiment starting with eggs (Gosner stage, GS 8) and another experiment starting with tadpoles (GS 21–24) using a full factorial design with 5 concentrations of the herbicide formulation Roundup® LB Plus (0.0 mg acid equivalent L−1, 0.5, 1.0, or 1.5 mg a.e. L−1 and a pulse treatment with 3 times (egg experiment) or 5 times (tadpole experiment) addition of 0.5 a.e. mg L−1 over the course of several weeks) and two temperature levels (15 and 20°C). Contrary to our expectation, our results showed that toad eggs are more sensitive to herbicides than tadpoles leading to an averaged 31% increase in total length, tail length, and body length compared to the herbicide-free control. Tadpole morphology, development, or mortality was not influenced by herbicides. There was no correlation between herbicide concentration and the effect strength on eggs or tadpoles. Higher temperature accelerated growth of both eggs and tadpoles. As one of the first we also observed interactive effects between herbicide concentrations and temperature especially for egg development resulting in more pronounced herbicide effects at lower temperatures than at higher temperatures. This is quite remarkable as ecotoxicologial risk assessment studies are usually conducted at a constant temperature, thereby perhaps not adequately examining non-target effects at natural conditions. more pronounced herbicide effects at lower temperatures than at higher temperatures. This is quite remarkable as ecotoxicologial risk assessment studies are usually conducted at a constant temperature, thereby perhaps not adequately examining non-target effects at natural conditions.

Background and purpose Detailed knowledge of quality of life (QoL) after permanent I-125 brachytherapy may aid in counselling patients with early-stage prostate cancer. Materials and methods Seventy-four consecutive patients with low-risk prostate cancer were asked to complete the EORTC QLQ-C30 questionnaire with the prostate-specific PR25 module before implant, four weeks and one year after implant (response rates 97%, 88% and 89%, respectively). Implant characteristics were correlated with QoL scores. Results Global QoL was stable from pre-treatment to one year after implant and similar to age-adjusted scores of healthy controls. Significant changes versus baseline in QLQ-C30 domains were worsened social function at four weeks, increased constipation at four weeks and at one year and improved emotional function at one year. PR25 urinary symptoms were significantly increased at four weeks and, despite some improvement, at one year; bowel symptoms were slightly increased. Both types of symptoms were most strongly related with pre-treatment symptom scores. Prostate-V150 was the only implant parameter significantly associated with both urinary and bowel symptoms at four weeks and one year. Conclusions Limiting the high-dose subvolume in the prostate may be beneficial to reduce urinary and bowel symptoms but the major determinant of symptoms after I-125 implant is the baseline symptom level.