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Oryzomys texensis Allen, 1894, the Texas Marsh Rice Rat, is a yellowish gray-brown oryzomyine rodent with whitish feet and venter, black eyes, small hairy ears, short vibrissae, and a tail about one-half of total length. It was elevated to species status based on the results of an extensive molecular genetics analysis of the O. palustris complex. The poorly defined eastern boundary of O. texensis includes Mississippi, Arkansas, southern Missouri, and southern Illinois, with populations extending westward to southeastern Kansas, eastern Oklahoma, eastern and coastal Texas, into northeastern Tamaulipas, Mexico. Present in tidal marshes and other habitats near water, O. texensis is omnivorous, with some populations being highly carnivorous. Oryzomys texensis Allen, 1894, es un roedor de la tribu Oryzomyini, de color marrón grisáceo amarillento con pies y vientre blanquecinos, ojos negros, pequeñas orejas velludas, vibrisas cortas y una cola que constituye aproximadamente la mitad de su longitud total. Fue elevado del nivel de subespecie de O. palustris a especie en base a resultados de un extenso análisis de genética molecular del complejo O. palustris. El margen oriental de la distribución geográfica de O. texensis está mal definido e incluye partes de Mississippi y Arkansas, así como el sur de Missouri y sur de Illinois, con poblaciones adicionales extendiéndose en dirección oeste hacia el sureste de Kansas, este de Oklahoma, planicie costera y este de Texas y hasta el extremo suroccidental de Texas y noroeste de Tamaulipas, México. Está presente en marismas, humedales, y otros hábitats cercanos al agua. Si bien es omnívoro, algunas poblaciones constan de individuos mayormente carnívoros.

The increasing intensity of wetland stressors in the Upper Midwestern United States hastens the need to understand how matrix composition influences wetland bird occurrence and abundance. The optimal spatial scale for assessing species–habitat relationships is not always apparent, but may affect inference about wetland use and suitability. We developed occupancy and abundance models, accounting for imperfect detection, for 9 wetland bird species breeding in Minnesota. We evaluated land cover associations at 3 spatial scales (12.6 ha, 50.3 ha, and 4,000 ha), quantified speciesspecific sensitivity to wetland availability and matrix habitat composition (agricultural and developed land covers), and assessed ecoregional variation in occupancy and abundance. Amount of wetland cover was positively associated with occupancy of 89% of species and with abundance of 67% of species, but the spatial scale of support differed among species. American Bittern (Botaurus lentiginosus), Pied-billed Grebe (Podilymbus podiceps), and Wilson's Snipe (Gallinago delicata) in particular were negatively impacted by anthropogenic land uses within the surrounding matrix, indicating a need to shift wetland conservation planning from the site scale to the landscape scale to capture pertinent drivers of wetland bird habitat use. Mean expected occupancy across all species was greatest in the Prairie Pothole Region (PPR), suggesting that restoration efforts within this ecoregion are likely to maintain wetland bird diversity. However, given the minimal total wetland availability and predominantly agricultural matrix in the PPR, protecting wetlands and upland buffers in the Aspen Parklands or Boreal ecoregions may represent a better investment for agricultural-sensitive species such as American Bittern, Sandhill Crane (Antigone canadensis), and Wilson's Snipe. Our modeling approach provides a multi-species framework for identifying habitat management priorities; future applications at broader spatial extents can continue to improve wetland bird conservation in a region with high rates of wetland loss and degradation.

The addition of cementing agents is a well-known way of stabilizing an unsatisfactory soil for design parameters. This research evaluates three soils, namely pink kaolin silty soil, Botucatu weathered sandstone residual soil and Osorio uniform sand, stabilized with Portland cement type III. Hydraulic conductivity measurements were performed with a flexible wall permeameter, following the recommendations of ASTM D5084; unconfined compressive strength tests were also carried out, in accordance with ABNT NBR 12025. The result of this research observed a gain in compressive strength, best described as a linear gain with the increase in cement content, and as a power function as porosity decreases. The measured hydraulic conductivity observed a general reduction, similarly, with a linear decrease in regards to increasing cement content and decreased as a power function in regards to decreasing porosity. The possible correlation of the output variables investigated suggests the existence of a grid-like relationship, which can be potentially useful in earthworks and more general applications.

Mangroves are coastal ecosystems dependent on saline water conditions, although freshwater is seasonally present in most types of mangroves. The riparian mangroves have a greater influence of freshwater than salty water, reducing saline stress and allowing greater productivity and diversity. As they are associated with freshwater channels, their hydrology makes them both a source and a sink for sediments, nutrients, and organic matter. The wetlands adjacent to riparian mangroves are mainly freshwater swamps or marshes. To monitor the composition and abundance of the vegetation and the production of litter and roots in the midterm, 27 monitoring units were monitored (22 in mangroves, five in wetlands) in two periods (2015–2016 and 2018–2019). In them, we evaluated biotic characteristics and root production annually, and monthly the litter production and pore and river water salinity. We detected a gradient of salinity spatially and temporally. The salinity gradually decreased as the distance to the river increased. In the winter of 2018–2019 saline intrusion increased the interstitial and river water values by an average of 10 (interstitial water) and 16‰, (river water). This increase caused a significant decrease in litter and root production and augmented the cover of Laguncularia racemosa (freshwater marsh), mortality of herbaceous species (Acrostichum danaeifolium, Typha domingensis, Phragmites australis), and tree species such as Annona glabra and Acoelorraphe wrightii.

Floodplains are some of the most productive and diverse ecosystems on Earth. The Usumacinta River Basin, in the Southern Gulf of Mexico, hosts several floodplain lakes, whose integrity is threatened by water resource development. We aimed to investigate how food webs in these ecosystems vary in relation to their hydrological connectivity and seasonal flood cycles. To do this, we combined analysis of water quality and stable isotopes in two lakes with permanent connection to the Usumacinta River and two isolated lakes during dry, early rainy and late rainy season. Significant differences in chlorophyll-a, nutrients and suspended solids were reflected in distinct trophic dynamics among lakes. Stable isotope analysis revealed that fish from all lakes relied predominantly on autochthonous primary production, but while phytoplankton was the dominant resource for fish in the isolated lakes, aquatic macrophytes made the highest contribution to consumers’ production in the connected lakes. Fish tended to have broader isotopic niches during the early rainy season, likely reflecting consumption of a wider range of resources following the first flow pulses of the year. Our study highlights the importance of hydrological connectivity and natural flow regimes to maintain the outstanding biodiversity and fishery yield of these floodplain ecosystems.

The spider fauna of the Everglades National Park in southern Florida was surveyed over 2 widely separated time periods: 1966 to 1967 and 2008 to 2009. Samples were made in 4 of the typical Everglades habitats: sawgrass prairie, willowhead marsh, pineland, and tropical hardwood hammock, as well as several “disturbed” areas. A total of 201 spider species was identified. Twenty-three additional taxa were identified only to genus and included for general Everglades information. One species was documented as new and undescribed, and several others possibly may be new. The Everglades National Park is located at the northern border of the Neotropical ecozone and the southern border of the Nearctic ecozone. Forty-seven percent of the species were Nearctic, 37% Nearctic/Neotropical, 12% Cosmopolitan, and 3% Neotropical. The greatest number of species was collected in the hardwood hammock habitat. Life cycles of 10 common species are provided.

Protected areas (PAs) have a unique value that relies on their high biological and cultural diversity, as well as their scenic beauty. Thus, they attract a large flow of tourists with recreational and/or educational purposes. The profits obtained from tourism support the PAs’ objective which is to preserve its natural and cultural resources and ensure its sustainable development, including the maximisation of benefits for the local communities. Nevertheless, inefficiencies in the tourism management of PAs can produce negative social outcomes, such as pollution or disparity in the distribution of economic benefits, negatively affecting residents’ quality of life. The Pantanos de Villa Wildlife Refuge (PVWR) is one of the most visited PAs in Peru and the only one located in an urban environment, which represents a challenge in its sustainable tourism management, especially in the social aspect. This research analysed the social impact of tourism in the PVWR, as perceived by residents located in its buffer zone. The study applied a qualitative methodology based on semi-structured in-depth interviews to 14 residents that allowed them to share their personal experiences with the social impacts identified in the literature and one non-academic source of evidence of the population’s comfort/discomfort with tourism. The study revealed 11 social impacts of tourism about which participants have a predominantly positive perception. For instance, participants agree that tourism promotes environmental education and improves public infrastructure, while a strong sense of belonging and pride was perceived among them. Nonetheless, participants have diverse perceptions of three social impacts, namely: employment and economic growth, citizen security, and opportunities for cultural exchange, possible indications of an unequal distribution of benefits or differing level of involvement of residents in the tourism activity. This is one of a few studies that addresses the impacts of tourism in PAs in Peru focusing on the social dimension, as most research focuses on the environmental one. In terms of practical contributions, the study suggests specific actions that the local authorities may apply to maximise the positive social impacts of tourism for all residents of the PVWR.

Este texto quiere mostrar algunos de los efectos teóricos que surgen al vincular la escritura con la vida y forma del pantano. Me detengo en ciertos momentos fundamentales de La amortajada (1975) de María Luisa Bombal para mostrar que leer con ojos vegetales permite descubrir nuevas relaciones textuales que contemplan la existencia de otras vidas en la literatura y que estimulan nuevas maneras de hablar del mundo. También propongo que la aparición de los fenómenos vegetales en la novela tiene alcances políticos importantes, pues Bombal enriquece el escenario de la escritura vegetal al darle agencia textual a la materia los reinos Plantae y animal. En este marco de ideas, la teoría, la creación literaria y la investigación se unen en una tríada poderosa gracias a los efectos de pensar a partir de la imagen del pantano.

Particulate organic carbon (POC) derived from inland water plays an important role in the global carbon (C) cycle; however, the POC dynamic in tropical rivers is poorly known. We assessed the POC concentration, flux, and sources in the Usumacinta, the largest tropical river in North America, to determine the controls on POC export to the Gulf of Mexico. We examined the Mexican middle and lower Usumacinta Basin during the 2017 dry (DS) and rainy (RS) seasons. The POC concentration ranged from 0.48 to 4.7 mg L−1 and was higher in the RS, though only in the middle basin, while remaining similar in both seasons in the lower basin. The POC was predominantly allochthonous (54.7 to 99.6%). However, autochthonous POC (phytoplankton) increased in the DS (from 5.1 to 17.7%) in both basins. The POC mass inflow–outflow balance suggested that floodplains supply (C source) autochthonous POC during the DS while retaining (C sink) allochthonous POC in the RS. Ranging between 109.1 (DS) and 926.1 t POC d−1 (RS), the Usumacinta River POC export to the Gulf of Mexico was similar to that of other tropical rivers with a comparable water discharge. The extensive floodplains and the “Pantanos de Centla” wetlands in the lowlands largely influenced the POC dynamics and export to the southern Gulf of Mexico.

Analysis of tsunami deposits from the Pantano Morghella area provided geological evidence for two inundations occurred along the south-eastern Ionian coast of Sicily. Pantano Morghella is a large pond characterised by a fine-grained sedimentation indicating a low-energy depositional environment. Two anomalous yellow sandy layers found at different depths indicate the occurrence of high-energy marine inundations. We studied sedimentological and paleontological features of the anomalous deposits as well as their spatial distribution observing the following properties: different facies with respect to the local stratigraphic sequence; erosive bases, rip-up clasts and broken elements testifying violent deposition mechanisms; macro and micro fauna of marine environment; relatively constant thickness throughout most of the depositional zone with thinning at the distal end; large sand sheets that extend inland. These observations, jointly with their infrequency in the sedimentary record and the age indicating a fast deposition, provided strong evidence for tsunami inundations. Correlations between anomalous layers and historical tsunamis are supported by radiocarbon and OSL dating results. The younger deposit is likely due to the 1908 near-source tsunami, whereas the flooding of the oldest event is most likely associated with a far and large source, the Crete 365 AD earthquake.