Response of a shallow Mediterranean lake to nutrient diversion: does it follow similar patterns as in northern shallow lakes?

1. In view of the paucity of data on the response of warm shallow lakes to reductions in nutrient loading, this paper presents a long‐term limnological data set to document changes in the food‐web of a shallow Mediterranean lake (Lake Albufera, Valencia, Spain) that has experienced reductions in phosphorus (P) (77%) and nitrogen (N) (24%) loading following sewage diversion. 2. Nine years after sewage diversion, P concentration in the lake was reduced by 30% but remained high (TP = 0.34 mg L^?1), although the mean water retention time in the lake was only 0.1 years. Nitrate concentrations did not significantly change, probably because the lake continued to receive untreated effluents from ricefields. 3. Chlorophyll a concentration was reduced by half (annual mean of 180 μg L^?1). Cyanobacteria abundance remained high but its composition changed towards smaller species, both filamentous and chroococcal forms. 4. Cladocera abundance increased and reached peaks twice a year (December to March and July to September). After nutrient reduction, short‐term clear‐water phases (up to 5 weeks) occurred during February to March in several years, concomitant with annual flushing of the lake and lower fish densities. The abundance of Cladocera in winter contrasted with the spring peaks observed in northern restored shallow lakes. The zooplankton to phytoplankton biomass ratio remained lower than in northern temperate shallow lakes, probably because of fish predation on zooplankton. 5. Improvement of the water quality of Lake Albufera remained insufficient to counteract littoral reed regression or improve underwater light allowing submerged plants re‐colonise the lake. 6. Sewage diversion from Lake Albufera impacted the food web through the plankton, but higher trophic levels, such as fish and waterfowl, were affected to a lesser degree. Although the fish species present in the lake are mainly omnivorous, long‐term data on commercial fish captures indicated that fish communities changed in response to nutrient level and trophic structure as has been observed in restored shallow lakes at northern latitudes. 7. Phosphorus concentrations produced similar phytoplankton biomass in Lake Albufera as in more northern shallow lakes with abundant planktivorous fish and small zooplankton. However, in Lake Albufera, high average concentrations were maintained throughout the year. Overall, results suggest that nutrient control may be a greater priority in eutrophicated warm shallow lakes than in similar lakes at higher latitudes.     

Growth-band counts from elephantfish Callorhinchus milii fin spines do not correspond with independently estimated ages

Fin spines from elephantfish Callorhinchus milii were sectioned and viewed with transmitted white light under a compound microscope. The sections displayed growth bands but their interpretation and significance were unclear. Three different methods were used for counting growth bands. The results were compared with reference growth curves based on length-at-age estimates for six juvenile year classes derived from length-frequency distributions, and tagging data that showed longevity is at least 20 years. None of the three ageing methods showed good correspondence with the reference curves and all methods departed markedly from the reference curves at ages above 2 years old. Therefore, growth bands present in C. milii spines are not useful for ageing, at least with the three methods tested here. Spine bands may not represent age marks, but instead may be layers of material deposited irregularly to strengthen the spine.     

High genetic variability in Neotropical myophilous orchids

The patterns of genetic variability of seven Bulbophyllum Thouars species were investigated using 14 enzymatic loci, and compared with those of other Neotropical myophilous orchid species. The genetic variability estimated was very high ( H _e = 0.39–0.61, P  = 86–100%, A  = 2.6–3.8), despite the small population sizes, which may be explained by the vegetative reproduction. Of the three species with multiple populations, only B. epiphytum showed moderate values of genetic structuring. Environmental characteristics and seed dispersal mechanisms are important in understanding the differences in the population structure observed. Almost all pairs of species showed low genetic similarity, indicating a long period of divergence. Our results suggest that B. adiamantinum and B. insectiferum , species currently classified in different sections of the genus, are more closely related than previously thought.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 33–40.     

Guías de práctica clínica para la valoración y tratamiento de la transexualidad. Grupo de Identidad y Diferenciación Sexual de la SEEN (GIDSEEN)*(anexo 1)

Transsexual patients can only be diagnosed and treated at functional gender identity Units with provision of high quality care, development of clinical practice guidelines, and interdisciplinary working groups. The therapeutic process has three mainstays: initial psychological diagnostic evaluation and psychotherapy, endocrinological evaluation and hormone therapy, and sex reassignment surgery. Cross-sex hormone therapy is essential for the anatomical and psychological transition process in duly selected patients. Hormones help optimize real-life sex identity, improve quality of life, and limit psychiatric co-morbidities often associated to lack of treatment. Development of this clinical practice guideline addresses the need for implementing a coordinated action protocol for comprehensive health care for transgender people in the National Health System.     

New piophilid in town: the first Palaearctic record of Piophila megastigmata and its coexistence with Piophila casei in central Spain

The genus Piophila Fallén (Diptera: Piophilidae) is known from only two species: Piophila casei (L.) is a major pest, a cosmopolitan species and is commonly used as a forensic indicator, whereas Piophila megastigmata McAlpine has until now only been recorded in a natural environment in South Africa. The present work reports the first occurrence of P. megastigmata in the Palaearctic region from specimens collected by carrion‐baited traps throughout different natural habitats of central Spain. Furthermore, the species was also collected with P. casei on corpses of domestic pigs used in a carrion succession study in a periurban habitat in central Spain. Both species occurred on carrion in different seasons, but P. megastigmata was more abundant than P. casei in autumn, arriving earlier at the carcasses and persisting for a longer period. The contrary pattern was observed in spring. The presence of P. megastigmata in different localities in central Spain and its coexistence with P. casei in a periurban habitat make it a potentially useful new tool for legal medicine in Europe; thus this species must be considered in forensic entomology studies.     

Increased resource use efficiency amplifies positive response of aquatic primary production to experimental warming

Climate warming is affecting the structure and function of river ecosystems, including their role in transforming and transporting carbon (C), nitrogen (N), and phosphorus (P). Predicting how river ecosystems respond to warming has been hindered by a dearth of information about how otherwise well‐studied physiological responses to temperature scale from organismal to ecosystem levels. We conducted an ecosystem‐level temperature manipulation to quantify how coupling of stream ecosystem metabolism and nutrient uptake responded to a realistic warming scenario. A ~3.3°C increase in mean water temperature altered coupling of C, N, and P fluxes in ways inconsistent with single‐species laboratory experiments. Net primary production tripled during the year of experimental warming, while whole‐stream N and P uptake rates did not change, resulting in 289% and 281% increases in autotrophic dissolved inorganic N and P use efficiency (UE), respectively. Increased ecosystem production was a product of unexpectedly large increases in mass‐specific net primary production and autotroph biomass, supported by (i) combined increases in resource availability (via N mineralization and N₂ fixation) and (ii) elevated resource use efficiency, the latter associated with changes in community structure. These large changes in C and nutrient cycling could not have been predicted from the physiological effects of temperature alone. Our experiment provides clear ecosystem‐level evidence that warming can shift the balance between C and nutrient cycling in rivers, demonstrating that warming will alter the important role of in‐stream processes in C, N, and P transformations. Moreover, our results reveal a key role for nutrient supply and use efficiency in mediating responses of primary producers to climate warming.     

Taking advantage from phenotype variability in a local animal genetic resource: identification of genomic regions associated with the hairless phenotype in Casertana pigs

Casertana is an endangered autochthonous pig breed (raised in south‐central Italy) that is considered to be the descendant of the influential Neapolitan pig population that was used to improve British breeds in the 19th century. Casertana pigs are characterized by a typical, almost complete, hairless phenotype, even though a few Casertana pigs are normal haired. In this work, using Illumina PorcineSNP60 BeadChip data, we carried out a genome‐wide association study and an F_ST analysis with this breed by comparing animals showing the classical hairless phenotype (n = 81) versus pigs classified as haired (n = 15). Combining the results obtained with the two approaches, we identified two significant regions: one on porcine chromosome (SSC) 7 and one on SSC15. The SSC7 region contains the forkhead box N3 (FOXN3) gene, the most plausible candidate gene of this region, considering that mutations in another gene of the same family (forkhead box N1; Foxn1 or FOXN1) are responsible for the nude locus in rodents and alopecia in humans. Another potential candidate gene, rho guanine nucleotide exchange factor 10 (ARHGEF10), is located in the SSC15 region. FOXN3 and ARHGEF10 have been detected as differentially expressed in androgenetic and senescent alopecia respectively. This study on an autochthonous pig breed contributes to shed some light on novel genes potentially involved in hair development and growth and demonstrates that local animal breeds can be valuable genetic resources for disclosing genetic factors affecting unique traits, taking advantage of phenotype variability segregating in small populations.