Algal mats transport diaspores and carpological remains in shallow lakes

Algal mats in lakes and reservoirs can transport diaspores and carpological remains of plants, and thus may influence the creation of taphocoenoses. In 2012, I quantified carpological remains in two types of algal mats from a small reservoir in southern Poland. Mats formed by filamentous algae participate primarily in the original transport of diaspores, and can influence their concentration and facilitate their migration, mainly between the shores of the reservoir. Diatom mats partake primarily in diaspore redeposition, but can also cause their dispersal between the shore zone and the central part of the reservoir. This research demonstrates that mats built by diatoms contain far more remains and are more biologically diverse than filamentous algal mats. Movement of carpological remains observed in both types of algal mats points to their role in the formation of taphocoenoses and suggests that algal mats must be considered when interpreting macrofossil records

Fostering coastal resilience to climate change vulnerability in Bangladesh, Brazil, Cameroon and Uruguay: a cross-country comparison

© 2017, Springer Science+Business Media B.V. This paper describes a comparative study of four different cases on vulnerability, hazards and adaptive capacity to climate threats in coastal areas and communities in four developing countries: Bangladesh, Brazil, Cameroon and Uruguay. Coastal areas are vulnerable to sea-level rise (SLR), storm surges and flooding due to their (i) exposure, (ii) concentration of settlements, many of which occupied by less advantaged groups and (iii) the concentration of assets and services seen in these areas. The objective of the paper is twofold: (i) to evaluate current evidence of coastal vulnerability and adaptive capacity and (ii) to compare adaptation strategies being implemented in a sample of developing countries, focusing on successful ones. The followed approach for the case evaluation is based on (i) documenting observed threats and damages, (ii) using indicators of physical and socioeconomic vulnerability and adaptive capacity status and (iii) selecting examples of successful responses. Major conclusions based on cross-case comparison are (a) the studied countries show different vulnerability, adaptive capacity and implementation of responses, (b) innovative community-based (CBA) and ecosystem-based adaptation (EbA) and (c) early warning systems are key approaches and tools to foster climate resilience. A recommendation to foster the resilience of coastal communities and services is that efforts in innovative adaptation strategies to sea-level rise should be intensified and integrated with climate risk management within the national adaption plans (NAPAs) in order to reduce the impacts of hazards

Nature-based solutions in Bangladesh: evidence of effectiveness for addressing climate change and other sustainable development goals

Many lower-income countries are highly vulnerable to the impacts of natural disasters and climate change, due to their geographical location and high levels of poverty. In response, they are developing climate action plans that also support their sustainable development goals, but conventional adaptation approaches such as hard flood defenses can be expensive and unsustainable. Nature-based solutions (NbS) could provide cost-effective options to address these challenges but policymakers lack evidence on their effectiveness. To address this knowledge gap, we focused on Bangladesh, which is exceptionally vulnerable to cyclones, relative sea-level rise, saline intrusion, floods, landslides, heat waves and droughts, exacerbated by environmental degradation. NbS have been implemented in Bangladesh, but there is no synthesis of the outcomes in a form accessible to policymakers. We therefore conducted a systematic review on the effectiveness of NbS for addressing climate and natural hazards, and the outcomes for other sustainable development goals. Research encompasses protection, restoration and participatory management of mangroves, terrestrial forests and wetlands, as well as conservation agriculture and agro-forestry, but there is an evidence gap for urban green infrastructure. There is robust evidence that, if well-designed, these NbS can be effective in reducing exposure to natural disasters, adapting to climate change and reducing greenhouse gas emissions while empowering marginalized groups, reducing poverty, supporting local economies and enhancing biodiversity. However, we found short-term trade-offs with local needs, e.g. through over-harvesting and conversion of ecosystems to aquaculture or agriculture. To maximize NbS benefits while managing trade-offs, we identified four enabling factors: support for NbS in government policies; participatory delivery involving all stakeholders; strong and transparent governance; and provision of secure finance and land tenure, in line with international guidelines. More systematic monitoring of NbS project outcomes is also needed. Bangladesh has an opportunity to lead the way in showing how high quality NbS can be deployed at landscape scale to tackle sustainable development challenges in low to middle income countries, supporting a Green Economic Recovery. Our evidence base highlights the value of protecting irreplaceable natural assets such as mangroves, terrestrial forests and wetlands, and the non-market benefits they deliver, in national planning policies

Hypotensive action of coumarin glycosides from Daucus carota

Daucus carota (carrot) has been used in traditional medicine to treat hypertension. Activity-directed fractionation of aerial parts of D. carota resulted in the isolation of two cumarin glycosides coded as DC-2 and DC-3. Intravenous administration of these compounds caused a dose-dependent (1-10 mg/kg) fall in arterial blood pressure in normotensive anaesthetised rats. In the in vitro studies, both compounds caused a dose-dependent (10-200 microg/ml) inhibitory effect on spontaneously beating guinea pig atria as well as on the K+ -induced contractions of rabbit aorta at similar concentrations. These results indicate that DC-2 and DC-3 may be acting through blockade of calcium channels and this effect may be responsible for the blood pressure lowering effect of the compounds observed in the in vivo studies