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Urban and agricultural soils: conflicts and trade-offs in the optimization of ecosystem services
No full text[KEYWORDS: Agriculture Ecosystem services Land use Management optimization Soil Urban Trade-off]
On-going human population growth and changing patterns of resource consumption are increasing global demand for ecosystem services, many of which are provided by soils. Some of these ecosystem services are linearly related to the surface area of pervious soil, whereas others show non-linear relationships, making ecosystem service optimization a complex task. As limited land availability creates conflicting demands among various types of land use, a central challenge is how to weigh these conflicting interests and how to achieve the best solutions possible from a perspective of sustainable societal development. These conflicting interests become most apparent in soils that are the most heavily used by humans for specific purposes: urban soils used for green spaces, housing, and other infrastructure and agricultural soils for producing food, fibres and biofuels. We argue that, despite their seemingly divergent uses of land, agricultural and urban soils share common features with regards to interactions between ecosystem services, and that the trade-offs associated with decision-making, while scale- and context-dependent, can be surprisingly similar between the two systems. We propose that the trade-offs within land use types and their soil-related ecosystems services are often disproportional, and quantifying these will enable ecologists and soil scientists to help policy makers optimizing management decisions when confronted with demands for multiple services under limited land availability.
Grammar or lexicon. Or: Grammar and lexicon? Rule-based and usage-based approaches to phonological variation
No full textHow does interannual trophic variability caused by vertical water mixing affect reproduction and population density of Daphnia longispina group in Lake Iseo, a deep stratifying lake in Italy?
No full textLake Iseo is a deep meromictic lake located in Italy. During the past 20 years (1993–2013), the lake has experienced complete mixing of the water column only in spring 2005 and 2006. The full overturn episodes in these 2 years resulted in an increase in nutrients in both years, but an increase in phytoplankton biovolume occurred in the surface layers only in 2005. Our study examined if the magnitude of vertical mixing and the resulting increase in concentrations of epilimnetic total phosphorous (TP) can help predict reproduction and abundance of the main primary consumers, the cladocerans. We investigated the lake for 9 years (2001–2009) and compared annual changes in the Cladocera community and reproduction of the Daphnia longispina group between years of full and partial mixing. During the complete vertical mixing years (2005 and 2006), the taxonomical composition of Cladocera did not change, and density relationships among taxa shifted slightly toward an increase in the population density of Daphnia spp. Phytoplankton biovolume was significantly related to Daphnia mean clutch size. The increase in TP subsequent to the complete vertical mixing during late winter–early spring also seemed to predict reproduction and population density of Daphnia species. To our knowledge, this is the first long-term field study highlighting the importance of vertical mixing depth and TP concentrations on Daphnia abundance and phenology in a meromictic–oligomictic deep lake.
Niger en Nederland: zoek de verschillen
No full textHeeft het zin om Nederland met Niger te vergelijken? Onlangs publiceerde het Amerikaanse Population Reference Bureau het World Population Data Sheet 2013. In feite is dit een soort demografische thermometer, die elk jaar de toestand van de wereldbevolking weergeeft in lange rijen cijfers en indrukwekkende overzichten. Niet minder dan 20 indicatoren worden gebruikt om ruim 200 landen te vergelijken. Dat is een enorme klus, ook omdat gegevens vaak ontbreken of cijfers
niet direct vergelijkbaar zijn. Maar cijfers alleen spreken niet aan. Het PRB, een ‘wereldleider’ waar het gaat om het toegankelijk maken van demografische informatie, kiest vaak voor onorthodoxe voorbeelden om zijn boodschap over te brengen. Dit keer belicht het rapport speciaal de grote verschillen in inkomen en rijkdom. En die verschillen zijn heel groot, ook binnen ontwikkelingslanden. De demografische gevolgen liegen er niet om. In Uganda, bijvoorbeeld, krijgen vrouwen uit het armste deel van de bevolking (de armste 20 procent) tweemaal zoveel kinderen als vrouwen uit de rijkste laag van de bevolking (de rijkste 20 procent). En kinderen uit die armere families hebben een veel grotere kans om voor hun 5de levensjaar te overlijden dan rijke kinderen.
Deciphering microbial landscapes of fish eggs to mitigate emerging diseases
No full texthttp://www.nature.com/ismej/index.html
