Central-northern Region Research Articles

The environmental and evolutionary history of Lake Ohrid (FYROM/Albania): interim results from the SCOPSCO deep drilling project

Abstract. This study reviews and synthesises existing information generated within the SCOPSCO (Scientific Collaboration on Past Speciation Conditions in Lake Ohrid) deep drilling project. The four main aims of the project are to infer (i) the age and origin of Lake Ohrid (Former Yugoslav Republic of Macedonia/Republic of Albania), (ii) its regional seismotectonic history, (iii) volcanic activity and climate change in the central northern Mediterranean region, and (iv) the influence of major geological events on the evolution of its endemic species. The Ohrid basin formed by transtension during the Miocene, opened during the Pliocene and Pleistocene, and the lake established de novo in the still relatively narrow valley between 1.9 and 1.3 Ma. The lake history is recorded in a 584 m long sediment sequence, which was recovered within the framework of the International Continental Scientific Drilling Program (ICDP) from the central part (DEEP site) of the lake in spring 2013. To date, 54 tephra and cryptotephra horizons have been found in the upper 460 m of this sequence. Tephrochronology and tuning biogeochemical proxy data to orbital parameters revealed that the upper 247.8 m represent the last 637 kyr. The multi-proxy data set covering these 637 kyr indicates long-term variability. Some proxies show a change from generally cooler and wetter to drier and warmer glacial and interglacial periods around 300 ka. Short-term environmental change caused, for example, by tephra deposition or the climatic impact of millennial-scale Dansgaard–Oeschger and Heinrich events are superimposed on the long-term trends. Evolutionary studies on the extant fauna indicate that Lake Ohrid was not a refugial area for regional freshwater animals. This differs from the surrounding catchment, where the mountainous setting with relatively high water availability provided a refuge for temperate and montane trees during the relatively cold and dry glacial periods. Although Lake Ohrid experienced significant environmental change over the last 637 kyr, preliminary molecular data from extant microgastropod species do not indicate significant changes in diversification rate during this period. The reasons for this constant rate remain largely unknown, but a possible lack of environmentally induced extinction events in Lake Ohrid and/or the high resilience of the ecosystems may have played a role.

Observations, projections and impacts of climate change on water resources in Arabian Peninsula: current and future scenarios

This study investigated the effects of climate change on water resources in the Kingdom of Saudi Arabia (KSA) using observational data and climate models. Data from 1950 to 2013 were analysed and modelled to provide a comprehensive reference document on the status of climate change in KSA. Climate predictions up to 2050 and 2075 were performed using seven climatic models, and the Standardised Precipitation Index was used to assess droughts over the past 64 years to avoid uncertainty in the form of inadequate precipitation records. The central-northern region received moderate rainfall (70–100 mm/year), while the central, north-eastern and south-western regions received the highest mean annual rainfall, ranging from 150 to 300 mm/year. Over time, the climate has become hotter, and rainfall has decreased slightly each year. The north-western and south-eastern regions received the lowest mean annual rainfall (4–50 mm/year). In terms of rainfall seasonality [coefficient variation (CV)], the central-northern region and the coastal regions had moderate annual rainfall variability (27–83 %); the central-western region had high variability (89–100 %). The eastern regions and Al-Riyadh had the highest variability, with CV values exceeding 100 % due to anomalies in the amount of precipitation over the years. The projection models predicted a declining trend in the mean annual precipitation for most regions of KSA under all of the studied scenarios. Models also showed a slight increase in the mean annual precipitation around the coastline of the Red Sea and in the southern regions. The drought analysis revealed that the whole of KSA has experienced long and extreme droughts presenting an alarming risk as most of these are agricultural regions. The risk will become extremely dangerous if the declining trend in rainfall continues, causing increasingly severe droughts.

Climate change in Algeria and its impact on durum wheat

According to IPCC reports, the Mediterranean basin and particularly the North African area are amongst the most vulnerable regions to climate change. However, the information concerning the North African zone is very limited, and studies on climate change have never been conducted in Algeria up to now. This paper aims at bridging this information gap and initiates a first research on the impact of climate change on durum wheat cropping, the most strategic commodity in the food system and in the national economy of Algeria. Climate projections for the distant future (2071–2100), obtained from the ARPEGE-Climate model of Meteo-France run under the medium A1B SRES scenario, are introduced into a simple agrometeorological crop model previously validated with field data. Two options for the sowing date are assessed: a dynamical date, chosen within the traditional sowing window by means of a rainfall criterion, or a prescribed date with supplemental irrigation on the same day. Crop development is modelled using thermal time, and maximum yield is determined from the accumulation of solar radiation. A water stress index is inferred from a daily water balance model, and actual yield is estimated from potential yield corrected by the water stress index. The model also takes into account the occurrence of dry periods during the growing season, which can induce partial or total failure of the crop cycle. Two stations, representative of two of the three agroclimatic areas where durum wheat is grown, were chosen: Algiers in the central northern region and Bordj Bou Arreridj in the eastern high plains. Climate change is not similar for both areas, but a tendency towards aridity is clear especially in spring. Future temperature and potential evapotranspiration increase in both regions with a maximum in spring and summer. In Algiers, rainfall will decrease throughout the year and mainly in spring and summer. Conversely, summer precipitation in Bordj Bou Arreridj will increase significantly. In both regions, the autumn rains will increase in the future climate, the possibilities of early sowing will be improved, crop cycle will be reduced, and harvest will take place earlier. In Algiers, yields tend to decrease in the future climate, whereas in Bordj Bou Arreridj, a dynamical (earlier) sowing will tend to keep yields at their current level.

Health system delay among patients with tuberculosis in Taiwan: 2003-2010.

BackgroundTaiwan has integrated the previous vertical tuberculosis (TB) control system into the general health care system. With the phase out of the specialized TB care system and the declining TB incidence, it is likely that clinical workers become less familiar with the presentation of TB, resulting in delay in TB diagnosis and treatment.MethodsWe used the detailed information of health care visits in the Taiwan National Health Insurance database to analyze the temporal pattern of the health system delay (HSD) among 3,117 patients with TB between 2003 and 2010.ResultsThe median HSD was 29 days (interquartile range 5–73 days), and the median delay increased from 26 days in 2003 to 33.5 days in 2008, thereafter slightly decreased to 32 days in 2010. Patient factors associated with a longer HSD included: aged 45–64 and ≧65 years (as compared to aged <30 years); females (as compared to males); an initial visit as an outpatient (as compared to an inpatient). Provider factors were an initial visit to a provider not specialized in TB (as compared to a TB-related provider), to a primary care clinic or to a medical center (as compared to a district hospital), and in Central region, Northern region, KaoPing region, Southern region and Taipei region (as compared to in Eastern region). Longer distances from the point of initial visit to that of treatment were associated with longer HSD. Patients who switched among different levels or different types of medical care services during their illness exhibited the longest HSD.ConclusionsIn countries where the TB care systems are being restructured from a vertical to a horizontal system, it is critical to monitor HSD and be aware of its increase. The potential increase in the HSD from 2003 to 2008 observed in this study is concerning and the decline of HSD after 2008 might be attributed to the launch of contact investigation. Our results call for actions to improve the efficiency of TB diagnosis in the health care system and to increase the awareness of TB among physicians and the general public.Electronic supplementary materialThe online version of this article (doi:10.1186/s12879-015-1228-x) contains supplementary material, which is available to authorized users.

Prevalence of hypertension and assessment of its impact on self-rated health in rural populations: a cross-sectional study in northern Senegal

High blood pressure (hypertension) is a growing public health problem, and its impact on the overall health of patients in Africa is not well known. The objective of this study was to determine its prevalence and its influence on self-rated health among people living in rural areas of Senegal. This cross-sectional study was conducted over a two-week period in the rural communities of Labgar and Lougré Thiolly, located in the central northern region of Senegal, in an agricultural area. Randomly recruited volunteers were questioned during direct individual interviews about socio-demographic (age, sex, marital status, education, occupation) and lifestyle data (smoking or alcohol, physical activity). Clinical data (medical history, weight, height, blood pressure, course of treatment) were also collected. Self-rated health (SRH) was assessed by asking if they felt their health was bad or good. We included 627 patients with a mean age of 40.93 ± 17.2 years (range: 15-100 years), 59.9% of them women. Illiteracy and overweight were more common among women than among men, and smoking and alcohol consumption more frequent in men. The overall prevalence of hypertension was 23.4% and did not differ significantly between men (24.9%) and women (22.4%)(P = 0.50). Self-rated health was similar in men and women (with respectively 66.9% and 72.9% reporting good health, P = 0.10). On univariate analysis, the factors associated with perceived health status were age (OR = 1.34, P = 0.04), smoking (OR = 2.16, P = 0.03), educational level (OR = 1.21, P = 0.04), and the presence of hypertension (OR = 0.63, P = 0.05). The multivariate regression analysis showed that among women, advanced age (≥50 years) and hypertension (≥140/90 mmHg) were associated with poorer perceived health, whereas for men, only smoking was significantly correlated with poor health status (OR = 0.41, P = 0.01). This study shows that hypertension is common in this rural area of Senegal and is significantly associated with a lower self-rated health in women but not men. In the absence of longitudinal studies in these populations and given the predictive value of SRH, this correlation suggests higher morbidity and mortality in women with hypertension.

Growth pattern analysis by stem analysis of Korean white pine (Pinus koraiensis) in the central northern region of Korea

The study was performed to find the growth pattern by stem analysis of Korean white pine (Pinus koraiensis) in the Central Northern Region of Korea. One standard tree from each of 16 sites was stemmed and analyzed for the study. For sampled trees, the age range was 16–77 years, diameter at breast height (DBH) was 15.8–44.4 cm, height was 9.3–24.0 m, and stem volume was 0.1002–1.8518 m3. The stem volumes by our study had higher values over 40 DBH compared to Korea Forest Research Institute measurements. The bark volume had no particular trend with DBH and height, while bark ratio tended to decrease with DBH and height. The DBH and height curves by age had a concave shape whereas volume curve had a convex shape. The average periodic annual increment (PAI) of DBH was the highest at age 15 (1.0 cm/yr), and the highest value of the mean annual increment (MAI) of DBH was 0.7 cm/yr at age 30. The highest values of PAI and MAI of height were 0.6 m/yr (age 15) and 0.5 m/year (age 25) respectively. The average PAI and MAI of volume continued to increase even after age 75. Growth percentages of DBH, height and volume tended to decrease with age, particularly rapidly at age 20–30. Volume growth percentage was much higher than diameter and height.

Phylogeography of Hepialus humuli (L.) (Lepidoptera: Hepialidae) in Europe: short distance vs. large scale postglacial expansions from multiple Alpine refugia and taxonomic implications

We explore the phylogeography of the common ghost moth, Hepialus humuli (Linnaeus) in Europe based on 1451 bp Cytochromeoxydase Subunit 1 (COI) mtDNA and 617 bp Ribosomal protein Subunit 5 (RpS5) ntDNA with special focus on populations in the Alps and surrounding regions, as well as northern Europe. While RpS5 fails to recover any phylogeographic signal, COI reveals a remarkable pattern with central European populations separated in four well-defined groups. The most divergent group is restricted to northern Italy and southern Austria and geographically isolated from the others; one group is found only in the central-northern region south of Lake Constance (Liechtenstein, western Austria) and co-occurs with the two other groups, from north-eastern Alps and north-western Alps respectively. We conclude that the southern and central groups are relicts from a previous Pleistocene glacial maximum, whereas the two latter groups were isolated during the last glacial maximum in a western and an eastern refugium respectively, the exact extends of these refugia are uncertain. The central group has subsequently interbred with the two other northern groups and probably only exists today as ancient mtDNA haplotypes. The north-western and north-eastern groups have spread considerably and overlap over a large part of their range in the Alps and surrounding areas. Following the last glacial maximum, the north-western group spread into western Europe as far as Normandy, but the English Channel has apparently acted as a dispersal barrier. The north-eastern group spread into eastern and northern Europe, including Scandinavia, and possibly into the Balkans as well. The British Isles as well as the North Atlantic islands groups, the Faroese and Shetlands were colonised from southern Scandinavia or northern Germany, likely via Doggerland. Despite the deep divergence in mtDNA between the populations in Italy and southern Austria, and the remaining populations, there are no consistent morphological differences, and we conclude that there is no evidence that the southern populations should be considered a separate species. Although the populations in the Shetland and Faroese islands are phenotypically distinct from most other populations, we find no genetic or genitalia morphological differences between these populations and the rest. We therefore conclude that they display what can be termed cryptic genetic homogeneity. As the phenotypic variation is not unique to these populations either, we synonymise the North Atlantic subspecies H. humuli thulensis Newman syn.n. with H. humuli humuli.

Damage Caused by Psyllids and Influence of Climatic Factors in Brazilian Accesses of Guava Trees Cultivated in Organic System

The psyllid (Triozoida sp.) is the primary pest of guava tree in the Central Northern region of S?o Paulo State, Brazil. The variation of climatic factors may influence directly or indirectly the behavior of agricultural pests. The present work had objectives to evaluate the damages caused by psyllid in accesses of guava trees in order to identify materials with potential resistance to pest and the possible correlations of the damage with the meteorological factors, in an orchard of guava conducted in an organic system. Eighty-five guava accesses were evaluated. Each one was analyzed at random 10 leaves containing the symptom of the psyllid attack, through visual range of notes. The averages of the notes were compared by Scott-Knott test at 5% probability. The 25 accesses with the highest average damage of psyllid had the data submitted to correlation (Pearson), with the minimum and maximum temperature (°C), precipitation (mm) and relative humidity (%). Guava accesses used commercially were the most susceptible to the attack of psyllid, compared to the selections, with an emphasis to access “L4P14”, “L7P28” and “L8P32B”, which were the least attacked. The study of correlation between psyllid damages and meteorological factors, must be used the medium temperature, relative humidity and rainfall accumulated in the period of 14 days before the evaluations. There is a positive correlation between minimum temperasture, precipitation and relative humidity with the damage of psyllids in leaves of guava.

Tayassu pecari (Link, 1795) (Mammalia, Cetartiodactyla): comments on its South American fossil record, taxonomy and paleobiogeography

Tayassu pecari is widely distributed across the Neotropical region, from northern Argentina to south-eastern Mexico. However, its fossil record is scarce; it is recorded since the middle Pleistocene to Holocene in Argentina, Brazil and Uruguay. This paper aims to: (1) update the systematic synonymy of this species; (2) review and update its geographic chronologic distribution and provide a new Lujanian record of Tayassu pecari in Buenos Aires Province and (3) discuss the paleoenvironmental and paleobiogeographical implications of this record. Considering the quantitative analysis performed, the fossil here recorded clearly integrates the group of Tayassu pecari. This specimen corresponds to the first record of Tayassu pecari in the central-northern region of the Buenos Aires Province. During Late Pleistocene, Tayassu pecari was distributed southern to its recent range, probably evidencing different paleoenvironment conditions. This species is the better adapted peccary to tropical and subtropical rainforests, but may also be present in arid environments. Consequently, Tayassu by itself is insufficient to infer the prevailing environmental conditions. However, according to the fauna associated with the specimen described here, it is possible to infer an open or semi-open and arid or semi-arid environment for the central-northern Buenos Aires region by Late Pleistocene times.

Diseminación del enverdecimiento de los cítricos en Puerto Rico.

El enverdecimiento de los cítricos (EC), causado por la bacteria limitada al floema Candidatos Liberibacter asiaticus (Ca. L. asiaticus), es una de las enfermedades más devastadoras para la citricultura en el mundo. La enfermedad afecta dramáticamente la producción de los árboles de cítricos.Después de la detección del EC en Puerto Rico, se realizó un monitoreo para la determinación de la diseminación del patógeno desde Febrero de 2011 hasta Marzo de 2012. Se tomaron muestras sintomáticas y asintomáticas en siete viveros y veinte huertos en la reglón central montañosa, costa sur, norte y noroeste de la Isla. Las muestras se procesaron en la clínica de diagnóstico de la Universidad de Puerto Rico, Estación Experimental Agrícola de Juana Díaz. En un total de 345 muestras se realizó la reacción en cadena de la polimerasa con los iniciadores OH y OI2. El EC se detectó en solamente 7.0% de las muestras provenientes de ocho huertos con un área de 235 hectáreas en las localidades de Adjuntas, Añasco, Cabo Rojo, Coamo, Dorado, Juana Díaz, Las Marías y Santa Isabel. En 42 muestras negativas para Ca. L. asiaticus se realizaron pruebas serológicas para identificar: el Virus de la Tristeza (VTC) y la Clorosis Variegada de los Cítricos (CVC). Las dos enfermedades se detectaron: VTC en una muestra de ciales, y CVC en 41 muestras de diferentes localidades. La detección periódica de la presencia de la bacteria en los huertos comerciales, el control del vector y la eliminación de árboles infectados con EC deberá implementarse para proteger la industria citrícola en la Isla.

Séroprévalence de Neospora caninum dans les élevages bovins laitiers de la région centre nord de l’Algérie

As there has been little research into the epidemiological status of bovine neosporosis in Algeria, the main aims of this study were to confirm the circulation of Neospora caninum in the country and to determine its seroprevalence in dairy cattle in five provinces of Algeria's central northern region by means of enzyme-linked immunosorbent assay and indirect immunofluorescence. A serological study of 186 dairy cattle declared brucellosis-free established an overall seroprevalence of 12.37%, confirming that N. caninum is circulating in dairy cattle and underlining the need to introduce systematic serological screening for neosporosis to limit its spread and prevent it from being perpetuated on Algerian farms.

The influence of programme differences on crime reduction in opioid maintenance treatment. An analysis of regional patterns in Norway

Aims: Design: Official national criminal records were cross linked with all patients who started opioid maintenance treatment in Norway from 1997-2003 (n=3221), including patients from four different health regions in Norway; the Eastern region (n=1717), the Southern region (n=751), the Western region (n=586) and the Central-Northern region (n=167). Patients in each region were divided into separate groups according to whether they were retained or not retained in continuous treatment.Findings: During opioid maintenance treatment, patients in all four treatment regions had a considerable reduction in criminal convictions compared to pre-treatment levels. Criminal convictions during treatment were associated with retention in treatment. Among patients in continuous treatment, significant differences were found in levels of criminal convictions among the four treatment regions during treatment. Compared to patients in the Eastern region, patients in the Southern and the Central-Northern region had respectively 44 and 81 percent less criminal convictions during treatment, and patients in the Western region had 60 percent more convictions. For patients not in continuous treatment, no statistically significant differences were found between the four regions during treatment.Conclusions: Differences in criminal convictions during treatment may be related to regional differences in treatment practice within the national OMT system. In all regions, criminal convictions during OMT were higher for patients dropping out of treatment. It is suggested that clinical staff should offer more support to patients at risk of dropping out of treatment.Background: Reduced criminal activity is an important outcome for opioid maintenance treatment (OMT).

Paleomagnetism of early cretaceous arapey formation (Northern Uruguay)

We report detailed rock-magnetic and paleomagnetic directional data from 35 lava flows (302 standard paleomagnetic cores) sampled in the Central-Northern region of Uruguay in order to contribute to the study of the paleosecular variation of the Earth’s magnetic field during early Cretaceous and to obtain precise Cretaceous paleomagnetic pole positions for stable South America. The average unit direction is rather precisely determined from 29 out of 35 sites. All A95 confidence angles are less than 8°, which points to small within-site dispersion and high directional stability. Normal polarity magnetizations are revealed for 19 sites and 10 are reversely magnetized. Two other sites yield well defined intermediate polarities. The mean direction, supported by a positive reversal test is in reasonably good agreement with the expected paleodirection for Early Cretaceous stable South America and in disagreement with a 10° clockwise rotation found in the previous studies. On the other hand, paleomagnetic poles are significantly different from the pole position suggested by hotspot reconstructions, which may be due to true polar wander or the hotspot motion. Our data suggest a different style of secular variation during (and just before) the Cretaceous Normal Superchron and the last 5 Ma, supporting a link between paleosecular variation and reversal frequency.

Geologia e hipsometria de bacias de drenagem do centro-norte catarinense (Brasil): implicações para a zona costeira

A região centro-norte do Estado de Santa Catarina/Brasil é composta basicamente pelas bacias hidrográficas dos rios Itajaí-Açu, Itapocu e Tijucas, drenando diretamente para o Atlântico Sul. O objetivo do presente trabalho é analisar e correlacionar a hipsometria dessas bacias para melhor entender a evolução holocênica e a dinâmica dos estuários e planícies costeiras associadas àqueles rios. Foram compilados dados gerais da cobertura geológico-sedimentar, topografia, dimensões e clima de cada bacia hidrográfica. Esses dados foram analisados e interpretados no contexto geomorfológico. Dados de hidrodinâmica e sedimentologia dos estuários e estratigrafia das planícies costeiras foram também considerados. Os resultados apontam diferenças importantes na geologia, topografia, perfis de talvegue e hipsometria das bacias estudadas. Foram também identificadas diferenças significativas na morfologia, dinâmica e estratigrafia das respectivas regiões estuarinas e planícies costeiras, que foram diretamente correlacionadas com as características das bacias de drenagem.

Trend of China land water storage redistribution at medi- and large-spatial scales in recent five years by satellite gravity observations

The GRACE (Gravity Recovery and Climate Experiment) satellite gravity mission has provided a new method to study land water mass redistribution at medi- and long-spatial scales in recent years. We estimate continental water mass redistribution in China using GRACE observations during 2003 to 2007. The results show some large regions with increase or decrease of land water mass storage in the central northern region, Tibetan Plateau, the Three Gorges region, the place where Qinghai, Sichuan and Gansu provinces meet, and the Altun Mountains region in the Xinjiang Uygur Autonomous Region. In the first two regions, it is obvious that water (ice) mass storages are decreasing. Water mass in the central northern region decreases at a linear rate of 2.4 cm/a equivalent water height, equal to 5.2 billion cubic meters per year during the five years’ period, and water mass depletion in Hebei Province is ∼ 4.5 billion cubic meters per year in the same period, which is consistent with the average water mass depletion of 4.0 billion cubic meters per year of overused underground water in the recent 30 years estimated by Hebei Province Water Resources Bureau. Furthermore, GRACE can detect the water mass accumulation of ∼ 5 cm equivalent water height within the region spreading over about 0.12 million square kilometers due to the Three Gorges dam construction in June 2003. We also find a water mass gain of ∼ 1.1 cm/a in the areas where Qinghai, Sichuan and Gansu provinces meet. This indicates that the climate of these regions has been becoming gradually humid in recent years.

Cercospora kikuchii aislada en la provincia de Santa Fe (Argentina): variabilidad genética y producción de cercosporina in vitro

The aims of the present study were to analyze the genetic variability of Cercospora kikuchii isolates and the in vitro cercosporin production, of these isolates obtained from soybean at the central-northern region of Santa Fe province (Argentina). Also the relationship between RAPD profiles and toxin production was also assessed. The strain C. kikuchii NBRC 6711 and 13 soybean isolates with symptoms of leaf blight were tested. Cercosporin production was analyzed by growing the fungus on Potato Dextrose Agar, extracting the toxin in alkaline medium and determining its concentration by spectrophotometry. The population of C. kikuchii studied showed variability, both genotypically, nine different groups were encountered, and have the ability to produce cercosporin. No relationship was found between toxin production and the RAPD profiles.

Biogeographical patterns of Chinese spiders (Arachnida: Araneae) based on a parsimony analysis of endemicity

AbstractAim The distributions of Chinese spiders are used to form biotic regions and to infer biogeographical patterns.Location China.Methods China was initially divided into 294 quadrats of 2° latitude by 2° longitude. The distributions of 958 species of spiders were summarized for each quadrat. Subsequently, these quadrats were pooled into 28 areas based on topographical characteristics and to a lesser extent on the distributions of spiders. Parsimony analysis of endemicity (PAE) was used to classify the 28 areas based on the shared distributional patterns of spiders.Results China was found to have seven major biogeographical regions based on the distributional patterns of spiders: Western Northern region (clade B2: Tibetan Plateau and Inner Mongolia‐Xinjiang subregions), Central Northern region (clade B3), Eastern Northern region (clade B4), Central region (clade C2), Eastern Southern region (clade C3), Western Southern region (clade C4), and Central Southern region (clade C5).Main conclusions The distributional patterns of Chinese spiders correspond broadly to geological provinces. A comparison of the geological provinces and the distributional patterns of spiders reveals that the spiders occur south of the geological provinces. Furthermore, a general biogeographical classification with five natural areas is suggested as follows: Tibetan Plateau, Central Northern, Eastern Northern, Western Northern (excluding Tibetan Plateau), and Southern regions.

Structural framework and Mesozoic–Cenozoic evolution of Ponta Grossa Arch, Paraná Basin, southern Brazil

The integration of structural analyses of outcrops, aerial photographs, satellite images, aeromagnetometric data, and digital terrain models can establish the structural framework and paleostress trends related to the evolution of Ponta Grossa Arch, one of the most important structures of the Paraná Basin in southern Brazil. In the study area, the central-northern region of Paraná State, Brazil, the arch crosses outcropping areas of the Pirambóia, Botucatu, and Serra Geral Formations (São Bento Group, Mesozoic). The Pirambóia and Botucatu Formations are composed of quartz sandstones and subordinated siltstones. The Serra Geral Formation comprises tholeiitic basalt lava flows and associated intrusive rocks. Descriptive and kinematic structural analyses reveal the imprint of two brittle deformation phases: D1, controlled by the activation of an extensional system of regional faults that represent a progressive deformation that generated discontinuous brittle structures and dike swarm emplacement along a NW–SE trend, and D2, which was controlled by a strike-slip (transtensional) deformation system, probably of Late Cretaceous–Tertiary age, responsible for important fault reactivation along dykes and deformation bands in sandstones.

Distribution, abundance, and habitat use of introduced Boa constrictor threatening the native biota of Cozumel Island, Mexico

Species introductions are among the most pervasive types of disturbance, seriously affecting island biota and ecosystem dynamics. The management of introduced generalist species, which may live in a wide range of environmental conditions, can be particularly difficult and is a major challenge for the conservation of native insular species. Boa constrictor was introduced onto Cozumel Island, Mexico, in 1971. The introduction of this generalist predator has affected negatively the native species (many of them endemic to the island) on which the boa feed. It is important to determine temporal variation in boa abundance, the areas of the island in which boas live, and the vegetation types they use in order to develop management strategies to reduce boa pressure on the native biota. We used nocturnal road transect sampling and occasional boa encounters during field work, to estimate boa distribution, abundance and habitat use, taking into account its spatiotemporal patterns on Cozumel Island. This study confirms that Boa constrictor is well established, widespread, and abundant on the island. Our results show that boas are distributed throughout Cozumel, in all vegetation types and geographical regions. Overall, there were 0.11 ± 0.03 boa/10 km road transect. There were no significant spatiotemporal differences in boa activity (time of day) and abundance (monthly, seasonally, by vegetation types or regions of the island). According to the habitat use analysis, there were, however, fewer boas than expected in the subdeciduous tropical forest we sampled and in the central-northern region of the island, which coincide with areas inhabited by humans. There were more boas in areas uninhabited by humans, and there was a tendency towards a greater proportion of dead boas in inhabited areas and live boas in uninhabited areas. Cozumel boas are habitat generalists, which are affected by human induced mortality in inhabited areas. There is a vast area uninhabited by humans, with natural vegetation, on the island where boas have suitable habitats available for their continuous existence on Cozumel. This situation, and the adaptability of the boa, makes the control or eradication of this introduced species a critical conservation challenge.

IDADE (Pb-Pb) E ASPECTOS PETROGRÁFICOS E LITOGEOQUÍMICOS DO COMPLEXO ALCALINO FLORESTA AZUL, SUL DO ESTADO DA BAHIA

The Floresta Azul Alkaline Complex (CAFA), is represented by a NE-SW elongated igneous body, with an exposed area of 200 km 2 , located in the central-northern region of the Southern Bahia State Alkaline Province. Two types of magmatic intrusion were recognized: (i) at the eastern part of complex, occur granitic rocks, presenting many dioritic inclusions, and (ii) the syenitic rocks are located in the western region. Pb-Pb ages obtained in single zircon crystals from granite (696 ± 11 Ma); diorite (688 ± 2 Ma) and syenite (688 ± 10 Ma) indicate that CAFA rocks were emplaced synchronously during a Neoproterozoic event. The main mafic mineral of the CAFA is biotite, whereas sodic amphibole and aegirine are sporadically found in the granitic and syenitic lithotypes. The textural features of these rocks, typified by the angular distribution of well-formed feldspar crystals, reflect the lack of significant deformation after crystallization. All the lithologic types from the complex have alkaline signature, characterized by the high contents of Nb (86-243 ppm), Y (22-43ppm), F (760-2600) and Cl (220-10.000). The distribution patterns of minor and trace elements suggest that the different rocks from CAFA are cogenetic.