Semi-monthly mean sea-level pressure maps for the Mediterranean area

Summary Semi-monthly mean sea-level pressure maps for the Mediterranean and adjacent areas are presented. Isobars have been drawn at 1-millibar intervals. The most significant features on the maps and the advantages of the mode of presentation are discussed briefly.

---

Zusammenfassung Es werden auf das Meeresniveau bezogene halbmonatliche mittlere Luftdruckkarten für das Mittelmeergebiet und die anstoßenden Länder vorgelegt. Die Isobaren wurden für Millibarabstände gezeichnet. Die wichtigsten Resultate der Karten und die Vorzüge der Darstellungsweise werden kurz besprochen.

---

Résumé Présentation de cartes de la pression moyenne semi-mensuelle, réduite au niveau de la mer, de la région méditerranéenne et des contrées voisines. Les isobares sont tracées de millibar en millibar. Brève discussion des traits principaux des cartes et des avantages de la méthode de représentation.

---

---

With 25 Figures.

---

The work reported in this paper has been supported by the Geophysics Research Division of the Air Force Cambridge Research Center, under Contract AF 19 (122)-466.     

Developing Governance Principles for Public Natural Resources

Wildlife governance principles (WGPs) identify desirable governance characteristics for wildlife conservation in the United States (US). The types of institutional, ecological, and socio-cultural challenges that WGPs are designed to address also affect governance of public natural resources other than wildlife and in places other than the US. This raises the possibility that a similar set of governance principles might help natural resource professionals working in other resource contexts address the particular challenges they face. We describe the process by which we developed WGPs and offer seven practically oriented questions to help natural resource professionals ascertain whether a similar set of principles could improve governance in their context. In some contexts, minor modification of WGPs might be appropriate; in others, the process by which we developed WGPs could serve as a blueprint for formulating appropriate principles.     

Relative contributions of sulfate- and iron(III) reduction to organic matter mineralization and process controls in contrasting habitats of the Georgia saltmarsh

The objectives of this study were to partition out the predominant anaerobic respiration pathways coupled to C oxidation and to further elucidate the controls of anaerobic C respiration in three major saltmarsh habitats at Skidaway Island, GA; the short form of Spartina alterniflora (SS), the tall form of S. alterniflora (TS), and unvegetated, bioturbated creekbank (CB). Geochemical analysis of pore water and solid phase constituents revealed that the SS site experienced highly reducing conditions with two orders of magnitude higher pore water sulfide inventories (1.884 mmol m⁻²) than TS (0.003 mmol m⁻²) and CB (0.005 mmol m⁻²), respectively. Conversely, reactive Fe(III) inventories at TS (2208 mmol m⁻²) and CB (2881 mmol m⁻²) were up to 7–9 times higher than at SS (338 mmol m⁻²). Incubations and intact core experiments indicated that reduction accounted for 95% (SS), 37% (TS) and 66% (CB) of total anaerobic respiration. There was no detectable Fe(III) reduction at SS, while Fe(III) reduction accounted for up to 70% of C oxidation in the 3–6 cm depth interval at TS and 0–3 cm depth of CB, and on average, approximately 55% of C oxidation over two-thirds of marsh surface area. Laboratory manipulations provided further evidence for the importance of Fe(III) reduction as the accumulation rates of fermentation products were high when Fe(III) reduction was inhibited by removing the Fe(III) minerals from highly bioturbated CB sediments with higher Fe(III) mineral contents. Anaerobic C oxidation, - and Fe(III)-reduction rates appeared to be highest at the TS site during active plant growth in summer. Overall results suggest that bioturbation by macrofauna is the overriding factor in modulating the pathway of C mineralization in the saltmarsh, whereas availability of organic substrates from plants is a key factor in controlling the C oxidation rate.