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2021 ◽  
Vol 3 ◽  
Author(s):  
Don Tripp ◽  
Jayson Eldridge ◽  
Sarah Burgess

The Bedrock Geologic Map of the Northern Half of the Bedford 30- X 60-Minute Quadrangle is an Esri File Geodatabase that contains six feature data sets, five geodatabase tables, and two raster data sets detailing the bedrock geology of the northern half of the Bedford 30- X 60-minute quadrangle in Indiana. This data set conforms to "GeMS (Geologic Map Schema)--a standard format for the digital publication of geologic maps." For more information on GeMS please refer to the supplemental information within this metadata.


Author(s):  
Michael R. Sandstrom ◽  
Michael J. O’Leary ◽  
Milo Barham ◽  
Yue Cai ◽  
E. Troy Rasbury ◽  
...  

Whitney et al. (2021) challenge our conclusions about rates of deformation and amount of uplift along the Cape Range, Western Australia, particularly the elevation constraints we place on the last interglacial shoreline along the northern half of Cape Range. They selectively focus almost entirely on the northern half of Cape Range, completely omitting our extensive analysis of the southern section, which provides the bulk of our paleo−sea-level interpretations. They also raise concerns about some of the nomenclature and methodology used. We thank them for the opportunity to clarify our results on the minor section of our paper they take issue to, and address their concerns below point by point.


2021 ◽  
Author(s):  
◽  
Graeme Peter Elliott

<p>This study aimed to find an explanation for the decline of yellowheads and formulate recommendations for management and further research on the species. There were three main lines of investigation: basic population ecology and behaviour; the effect of introduced predators on breeding; and the habitat relationships of the species. A detailed study of a yellowhead population in the Eglinton Valley in Fiordland National Park was undertaken. Birds were caught and banded and their behaviour, breeding and survival monitored for 4 years. The relationship between yellowhead distribution and vegetation, topography, and fertility were investigated in part of Mt Aspiring National Park during one summer.  Yellowheads suffered high rates of predation from stoats during "plagues" that occurred after heavy beech seeding. Three aspects of yellowhead biology made them vulnerable to mammalian predation: (1) they nested in holes and predators killed not only eggs and nestlings, but also incubating adults; (2) only the females incubated, thus losses to predators had a greater effect on the population than if equal numbers of males and females were killed; and (3) yellowheads nested later than most other forest passerines and were still nesting when stoat numbers reached their summer peak. Though the yellowhead's hole nesting habit made them vulnerable to mammals it restricted nest parasitism and predation by long-tailed cuckoos and hole nesting is likely to have evolved in response to cuckoos. Yellowheads were found to be tall forest specialists; they occurred more frequently in tall forests than short ones, and preferentially used the largest trees. Their choice of nest sites had no effect on their preference for any forest types. The forests they favoured grew mainly on fertile valley floors at low altitudes. Yellowhead populations in "good habitats" raised two broods a year and these populations are probably sufficiently productive to withstand stoat plagues occurring once every 5 years, the average frequency of this event. Populations in "poor habitats" raise only one brood and their productivity is probably insufficient to match losses to stoats. Such populations are probably slowly declining, and are very vulnerable to extinction. A habitat suitability index was devised and forests in the north of the South Island from which yellowheads have disappeared, were compared with those in the south where yellowheads persist. Northern forests were as good for yellowheads as southern ones. Thus, the combination of habitat preference and predation cannot account for the recent disappearance of yellowheads from the northern half of the South Island. The decline in yellowheads was attributed to both predation by introduced mammals and competition with introduced vespulid wasps. Predation may have eliminated yellowheads from podocarp-dominated forests where predator numbers are constantly high, but they survive in some beech forests where predator numbers rise only once every five years. However, even within beech forests only the most productive populations are sufficiently productive to survive predation and these populations are probably susceptible to competition with wasps which eat large numbers of invertebrates. Yellowheads are likely to be more vulnerable to wasp competition than other forest insectivores because: (1) predation has reduced their productivity more than other birds because they nest in holes; (2) they are specialised in low altitude, tall forest that the wasps also favour; (3) their breeding is later than most other forest birds and their period of juvenile dependence much longer. Yellowheads are still feeding fledgling yellowheads at the time when wasps numbers reach their peak in the autumn, whereas the offspring of other forest birds are independent by this stage.</p>


2021 ◽  
Author(s):  
◽  
Graeme Peter Elliott

<p>This study aimed to find an explanation for the decline of yellowheads and formulate recommendations for management and further research on the species. There were three main lines of investigation: basic population ecology and behaviour; the effect of introduced predators on breeding; and the habitat relationships of the species. A detailed study of a yellowhead population in the Eglinton Valley in Fiordland National Park was undertaken. Birds were caught and banded and their behaviour, breeding and survival monitored for 4 years. The relationship between yellowhead distribution and vegetation, topography, and fertility were investigated in part of Mt Aspiring National Park during one summer.  Yellowheads suffered high rates of predation from stoats during "plagues" that occurred after heavy beech seeding. Three aspects of yellowhead biology made them vulnerable to mammalian predation: (1) they nested in holes and predators killed not only eggs and nestlings, but also incubating adults; (2) only the females incubated, thus losses to predators had a greater effect on the population than if equal numbers of males and females were killed; and (3) yellowheads nested later than most other forest passerines and were still nesting when stoat numbers reached their summer peak. Though the yellowhead's hole nesting habit made them vulnerable to mammals it restricted nest parasitism and predation by long-tailed cuckoos and hole nesting is likely to have evolved in response to cuckoos. Yellowheads were found to be tall forest specialists; they occurred more frequently in tall forests than short ones, and preferentially used the largest trees. Their choice of nest sites had no effect on their preference for any forest types. The forests they favoured grew mainly on fertile valley floors at low altitudes. Yellowhead populations in "good habitats" raised two broods a year and these populations are probably sufficiently productive to withstand stoat plagues occurring once every 5 years, the average frequency of this event. Populations in "poor habitats" raise only one brood and their productivity is probably insufficient to match losses to stoats. Such populations are probably slowly declining, and are very vulnerable to extinction. A habitat suitability index was devised and forests in the north of the South Island from which yellowheads have disappeared, were compared with those in the south where yellowheads persist. Northern forests were as good for yellowheads as southern ones. Thus, the combination of habitat preference and predation cannot account for the recent disappearance of yellowheads from the northern half of the South Island. The decline in yellowheads was attributed to both predation by introduced mammals and competition with introduced vespulid wasps. Predation may have eliminated yellowheads from podocarp-dominated forests where predator numbers are constantly high, but they survive in some beech forests where predator numbers rise only once every five years. However, even within beech forests only the most productive populations are sufficiently productive to survive predation and these populations are probably susceptible to competition with wasps which eat large numbers of invertebrates. Yellowheads are likely to be more vulnerable to wasp competition than other forest insectivores because: (1) predation has reduced their productivity more than other birds because they nest in holes; (2) they are specialised in low altitude, tall forest that the wasps also favour; (3) their breeding is later than most other forest birds and their period of juvenile dependence much longer. Yellowheads are still feeding fledgling yellowheads at the time when wasps numbers reach their peak in the autumn, whereas the offspring of other forest birds are independent by this stage.</p>


Author(s):  
Aioub Sofizadeh ◽  
Mohammad Reza Abai ◽  
Hassan Vatandoost ◽  
Ahmad Raeisi ◽  
Mohammad Sistanizadeh-Aghdam

Background: Malaria resurgence has occurred in the northern half parts of Iran. The resurgence of malaria in the prone area could arise from various factors, e.g. wide use of pesticides in the agriculture sector and factors such as habitual patterns of movement of local people from problematic southeastern foci in Iran toward the Caspian Littoral. There are no new data on the re­sistance status of main malaria vectors in the Caspian Littoral, and this study was aimed at renewal data on conventional insecticides. Methods: The field strain of adult Anopheles superpictus and Anopheles maculipennis were collected using the hand catch method and transferred to the laboratory. The susceptibility tests were carried out against DDT 4%, Malathion 5%, Permethrin 0.75%, Deltamethrin 0.05%, and Lambda-cyhalothrin 0.05%, followed by the WHO’s procedure. Results: The primary malaria vector in Caspian Littoral is An. maculipennis, revealed to be still resistant to DDT and mortali­ty rate, LT50 and LT90 of female mosquitoes were 75.0%, 54.2, minutes and 111.3 minutes. The under ’verifica­tion re­quired’ status of An. maculipennis was also revealed to Lambda-cyhalothrin based on recent WHO’s criteria. The ma­laria vector An. superpictus is also considered the second malaria vectors in the west parts of the studied area, which showed to be susceptible to all insecticides tested. Conclusion: DDT resistance is persisted in An. maculipennis despite stopping residual spraying with DDT since 1978 in the Caspian Littoral, but the occurrence of pyrethroid under ’verification required’ status is a progressive threat to the possible development of cross-resistance in the future.


2021 ◽  
Vol 9 ◽  
Author(s):  
Do Van Tu ◽  
Kristina von Rintelen ◽  
Werner Klotz ◽  
Le Hung Anh ◽  
Tran Anh Tuan ◽  
...  

Freshwater shrimp of the family Atyidae De Haan, 1849 have been studied in Vietnam for more than a century. A total of 24 species of atyid shrimps from the genera Caridina H. Milne Edwards, 1837, Neocaridina Kubo, 1938, Atyopsis Chace, 1983 have been recorded from Vietnam. With 22 species, the majority are from the genus Caridina. In 2013, Karge and Klotz mentioned the occurrence of four yet undescribed species belonging to Paracaridina Liang, Guo &amp; Tang, 1999 in Vietnam without taxonomic details. In general, studies of freshwater atyids in Vietnam are limited and most Vietnamese taxa await a taxonomic revision. The available data do not fully reflect their estimated species diversity in the country and distribution data are deficient. Here, we focus on four species of atyid shrimps from two genera, viz. Caridina cantonensis Yu, 1938, C. lanceifrons Yu, 1936, C. serrata Stimpson, 1860 and Neocaridina palmata (Shen, 1948), all described from China and have been reported to occur in Vietnam. The previous reports on the occurrence of these species in Vietnam are largely unreliable due to taxonomic confusion. To contribute to the knowledge of these taxa, we provide the first verified distribution records of the four species in the country with some taxonomic remarks. This study shows the first taxonomically-verified distribution data of four atyid shrimp species originally described from China, but also reported from Vietnam, albeit under various species names and, in some cases, erroneously. These data allow the first meaningful discussion of the distribution in light of the reproductive strategy of these four species and, in conjunction with the taxonomic remarks, will contribute to the knowledge of these taxa. As a result of this research and data from previous studies, we now consider all four species as widespread and non-endemic, but land-locked (with a complete freshwater life cycle). In Vietnam, all four species are confined to the northern half of the country. Beyond Vietnam, we provide the first records for Caridina lanceifrons from southern Thailand, which suggests a major sampling gap in Indochina.


Author(s):  
Cameron Goble ◽  
Troy G. Zorn ◽  
Nancy A. Auer ◽  
J. Marty Holtgren ◽  
Dan W. Mays ◽  
...  

Arctic Grayling Thymallus arcticus were historically found throughout the northern half of Michigan’s Lower Peninsula but were extirpated from the state by 1936. By addressing issues from previous reintroduction efforts and employing instream rearing (Remote Site Incubator) approach to stocking, numerous partners are working to reintroduce Arctic Grayling to Michigan with hopes of reestablishing self-sustaining populations. With over 47,000 km of coldwater stream habitat in the state and limited numbers of eggs for reintroductions, a prioritization framework was needed to provide a standardized, fine-scale method for rating suitability of streams for reintroductions. Through facilitated discussions with stakeholders and experts, we developed an overall prioritization framework for rating Michigan streams with components evaluating a reach’s thermal, instream habitat, biological, and connectivity characteristics.  Within the context of this broader framework, we developed the habitat rating component for assessing suitability of instream conditions for egg, fry, juvenile, and adult life stages of Arctic Grayling. Life-stage specific habitat metrics and scoring criteria from this effort were used to rate habitat conditions for 45 reaches in tributaries of Michigan’s Manistee River, enabling identification of reaches likely having instream habitat most suitable for Arctic Grayling. Numbers of reaches meeting or exceeding 60%, 70%, and 80% of the maximum score for overall habitat suitability were 31, 8, and 1. Upon completion of the fish assemblage and connectivity components, the prioritization framework and habitat rating process described here will be used for comparing suitability among streams throughout the historic range of Arctic Grayling in Michigan and guiding reintroduction efforts. Though it will take considerable time before instream habitat suitability criteria can be evaluated for all life stages of Arctic Grayling in Michigan, the collaborative stream prioritization framework developed for Arctic Grayling reintroduction can be readily adapted to reintroduction efforts for other species elsewhere.


Geosciences ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 358
Author(s):  
Emma Wilson Kelly ◽  
Felix Jose

Hurricane Charley made landfall on the Gulf Coast of Florida on 13 August 2004 as a category 4 hurricane, devastating North Captiva Island. The hurricane caused a breach to occur to the southern end of the island, which naturally healed itself over the course of three years. By 2008, the cut was completely repaired geomorphologically. LiDAR data analysis shows the northern half of the island has been subjected to persistent erosion from 1998–2018, while the southern half experienced accretion since 2004, including the complete closure of the “Charley cut”. The maximum volume of sediment erosion in the northern sector of the island (R71–R73) from 2004–2018 was −85,710.1 m3, which was the source of southern accretion. The breached area of the island (R78b–R79a) obtained 500,163.9 m3 of sediments from 2004–2018 to heal the cut made by Hurricane Charley. Along with LiDAR data analysis, Google Earth Pro historical imageries and SANDS volumetric analysis confirmed the longshore transport of sediments from the northern to the southern end of the island. Winter storms are mainly responsible for this southerly longshore transport and are hypothesized to be the main factor driving the coastal dynamics that restored the breach and helps in widening the southern end of North Captiva Island.


MAUSAM ◽  
2021 ◽  
Vol 71 (1) ◽  
pp. 79-94
Author(s):  
MAHMOUDI PEYMAN ◽  
JAHANSHAHI SEYED MAHDI AMIR ◽  
MORADI ZOHREH

The current study aims to model the behaviour of wet and dry days in Iran using Markov Chain Models. To this end, data related to daily precipitation of 44 synoptic stations for a 25-years interval (1991-2015) was obtained from Iran Meteorological Organization. Then, the Markov features of dry and wet days of Iran including stationary probabilities of dry and wet days occurrence, the expected length of dry periods, the expected length of wet periods, dry-wet spells cycle, return periods for dry or wet episodes and finally, the possibility of occurrence of the continuity of dry days for 5, 10, 15, 20, 25 and 30 days were calculated for all the synoptic stations in a seasonal scale. The results showed that there is the occurrence of dry short continuities (5 and 10 days) in three seasons of autumn, winter and spring with different possibilities all over Iran. However, the possibility of occurrence of long-term dry continuities (more than 20 days) is variable in terms of season and place so that in winter, no possibility of occurrence of this type of continuities is obvious in the northern half of Iran. As in autumn and spring those are the end and beginning of long-term stability conditions of the atmosphere in the upper atmosphere levels of Iran, the possibility of periodical occurrence of 30-days dry days, particularly in the southern half of Iran increases. In addition, the expected return periods for dry days is almost steady for every part of Iran and is in the range between 1 and 2 days. However, the number of return days to a precipitation period does not follow this rule and varies for every part of Iran so that from 2.15 days in autumn to 79 days in spring is variable, pointing to the climate diversity of Iran.


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