Permanent Watercourses Research Articles

Dead or alive? Antipredatory mechanism of Adenomera hylaedactyla (Cope, 1868) (Anura: Leptodactylidae) in northeastern Brazil

Anurans inhabit different types of environments, so these animals have developed a wide variety of defense mechanisms throughout evolutionary processes. During fieldwork in Serra dos Matões, municipality of Pedro II, state of Piauí, northeastern Brazil, we found an individual of Adenomera hylaedactyla on the edge of a permanent watercourse, in a transition area between Cerrado and Caatinga. Upon contact, the specimen exhibited “limb interweave” behavior, in which the individual extends and intertwines the hind limbs as a defense mechanism. There are no records of this defense mechanism in Adenomera species, making this work the first documented record of “limb interweave” for this genus. It should be emphasized that the evolution of species is closely related to the different types of behavior exhibited during interspecific interactions, therefore, such behaviors can influence speciation processes.

Practical experience in the construction of roads in difficult soil conditions

One of the most important and urgent problems is constructing roads in difficult soil conditions, ensuring their strength, reliability, and normal operation. To create an efficient and competitive transport infrastructure in Kazakhstan, the State Programme of Infrastructural Development “Nurly Zhol” for 2020–2025 was developed. Its main objectives are to improve the technological, scientific, and methodological base, provide resources, and to attract “Big Transit”. The paper presents the details of the survey carried out in one of road construction areas. Irrigation canals and periodic and permanent watercourses represent the hydrographic network of the construction site. The analysis of these features and field tests were included in the research. Stamp tests were performed to analyse mechanical properties of embankment soil to provide more reliable information on the mechanical properties of the soil. Structural and technological solutions were adopted based on the field tests and surveys of hydrological conditions. A numerical simulation was used to determine the stability of the road embankment, the results of which showed maximum deformations of 4.5 mm during the operation of road transport. Geosynthetic material was used to reinforce the subgrade. The results of the study have shown that the analysis of factors affecting the stability of engineering structures on difficult soil conditions helps to achieve some improvement.

BREEDING ECOLOGY, NESTING HABITAT AND THREATS TO A BLACK-AND-CHESTNUT EAGLE SPIZAETUS ISIDORI POPULATION IN THE MONTANE FORESTS OF CENTRAL PERU

The Black-and-chestnut Eagle Spizaetus isidori is an endangered and little-known top predator of South American montane forests. To better understand the breeding ecology and threats of this eagle, we studied several pairs between 2017 and 2022 in the central Andes of Peru. We recorded 62 adults, one immature, and 36 juveniles in 36 territories. These territories were in mountainous areas (altitudinal range 690–3,810 m a.s.l.), widely covered by montane forests (43.8–99.7% cover), and secondarily by open land (0.3–56.2% cover), far from urban settlements (1.3–27.1 km). Nesting sites (N = 15) were at medium altitudes (1,330–2,330 m a.s.l.) in steep hillsides or ravines (15–55°), having no preferential cardinal orientation, and relatively close to permanent water courses (20–800 m), open areas (30–930 m) and sites with human activity (120–2,200 m). Nests (N = 15) were placed at the top of tall (28–40 m) and thick-stemmed (DBH range 0.53–1.52 m) emergent trees of nine genera, with Ficus and Juglans being the most used. Incubation and brood-rearing occurred during the dry season (Mar–Nov). The wooded slopes where the eagles nested are being replaced by crops and livestock pastures, causing an estimated loss of 218.2 km2 of forest cover in our study area (5,056 km2) during the last 20 years. We detected human persecution in 55.5% of the territories, resulting in 26 juveniles, four adults, two immatures, and nine unaged eagles killed. Preventing the local extinctions of these eagles will require long-term population monitoring, improving knowledge of its ecology, mitigation of human-eagle conflict, development of education programs, and strengthening of land use inspection.

Temporal variation of the water quality of a permanent watercourse: case oued bousselam.

In order to assess the degree of pollution of surface water from Boussalem river from the city of Setif, we conducted during 2014; a study of physical and chemical characteristics of surface water. The results showed that water is loaded into mineral matter in terms of electrical conductivity (Avg = 1059,18 μS/cm ± 631,7), in turbidity (Avg = 15,713 NTU ± 22,19), in TSS (Avg = 189 mg/l ± 119,5), with low dissolved oxygen (Avg = 2,98 mg/l ± 2 ,44). The pH is closed to neutrality (Avg = 7,78 ± 0,74), the temperature is 17°C ± 11,13). Also, one revealed according to the results which water of Bousselam river is bad according to the quality standards of surface water and this is directly related to factors anthropic.

Modeling the content of chloroform in drinking water infiltration intake by periods of the annual cycle: low-water and permanent watercourse

The results of a study to find a relationship between the chloroform content in drinking water and the parameters characterizing water quality over an eighteen-year period of the infiltration water intake operation are presented. To increase the reliability of the model, the annual cycle is divided into two periods: an extended flood, including four months (April - June) and a period of low water and permanent watercourse, including eight months (August - March). Three time series were formed from the initial data: from the monthly average values of the parameters for the entire observation period; as a result of averaging the parameter values corresponding to each year; average values characterizing the low-water period and permanent watercourse for the entire observation period. It was found that the period of low water and permanent watercourse can be described by regression equations characterized by a smaller value of the average approximation error and a large value of the correlation coefficient. It was revealed that April introduces a significant stochasticity in the annual period. It is shown that the results obtained can be used to assess the value of the chloroform content in drinking water.

Hydrochemical characterization of the coastal springs of the Sierra de Irta. Maestrazgo Aquifer (Castellón)

El Maestrazgo aquifer has an approximate surface area of 2400 km2 and occupies the northern half of the province of Castellón, from the coast to Morella. This system is characterized by the absence of important springs in its interior and permanent water courses, in such a way that its fundamental discharge is carried out directly into the sea through springs located along the Sierra de Irta, between Alcossebre and Peñíscola. Several of these discharge points are permanent (springs at Playa de Las Fuentes, Torre Badum, Font de Dins and Prat de Peñíscola) and drain an important volume of water resources that is difficult to quantify. In addition to these well-known springs, in times of high water and mainly after episodes of intense rainfall, occasional springs appear whose precise location and chemical characteristics have not been defined to date. These are the springs of Playa del Carregador, Playa de Las Fuentes Sur and Norte, Playa del Russo and Playa del Pebret. In this article, the waters of all these springs are chemically characterized based on their majority ion content and are classified into five different types. The chosen samples are taken in periods of high water in which all the springs are running, but in a temporary stage relatively far from the torrential events that activated them so that the characterization corresponds to a hydrodynamic context as little altered as possible by the effect of the weather.

Where humid and arid meet: Sedimentology of coastal siliciclastic successions deposited in apparently contrasting climates

AbstractDeciphering the palaeoenvironmental and palaeoclimatic setting of ancient successions that include deposits typical of different climates can be challenging. This is the case in the Late Jurassic succession cropping out in eastern Spain (South‐Iberian and western Maestrazgo basins), where deposits characteristic of both arid to semiarid and humid to subhumid settings have been identified through a detailed analysis of eight stratigraphic sections. These sections comprise shallow marine carbonates changing upward and laterally to a predominantly siliciclastic coastal and alluvial succession, including abundant dinosaur remains. Deposition of coastal and alluvial sediments occurred in flood plains, ephemeral and perennial fluvial channels, aeolian dunes, deltas, distributary mouth‐bars and associated distributary channels, and shallow water bodies influenced by both fresh and marine waters. Some of these deposits, notably those of aeolian and ephemeral fluvial origin, are characteristic of arid to semiarid climates. However, there are also abundant deposits that can be demonstrably shown to have a coeval origin, which are indicative of permanent water courses: (i) sediments of seasonal discharge fluvial channels with perennial to semi‐perennial flow, displaying subcritical and supercritical flow sedimentary structures; (ii) deltaic sediments deposited in permanent freshwater bodies; and (iii) abundant plant and dinosaur remains, especially of herbivorous dinosaurs, which required the presence of permanent water sources and abundant vegetation. These apparently contrasting sedimentary features indicate that deposition occurred under a seasonal climate controlled by monsoonal‐type precipitation. These deposits are analogous to those observed nowadays in the Lençóis Maranhenses National Park (north‐east Brazil), where a subhumid tropical climate with a seasonal precipitation pattern prevails. Thus, this study shows that only through careful facies analysis and interpretation of depositional processes that can be shown to be occurring concurrently in neighbouring and related depositional systems can the detailed palaeoenvironmental and palaeoclimatic setting of complex coastal sedimentary successions be confidently reconstructed in detail.

Aufeis in the mountainous areas of the northwestern part of the Selenga River basin

The article presents the results of research on aufeis (icings) in the area where their concentration is maximal for the Selenga River basin. Landsat and Sentinel satellite imagery data were used to map the current location of aufeis in the valleys of permanent watercourses of the transboundary Dzhida River basin. It was found out that up to 3.5 thousand small aufeis with the area from 0.005 to 1 km2 are formed in small watersheds of the territory. The total area of aufeis within the considered territory can reach up to 92.1 km2, the aufeis coverage is 0.45%. It is revealed that in the total amount, small aufeis prevail, the area of which lies within 0.01 to 0.1 km2. In addition, ecosystem and economic aspects of the processes of ice formation on the territory of Russia and neighbouring Mongolia are considered.

Biofilm pigments in temporary streams indicate duration and severity of drying

AbstractIncreased duration and frequency of droughts under global change may affect both temporary and formerly permanent watercourses. Streambed desiccation, cooccurring solar radiation, and high temperature all may affect the composition and metabolism of photoautotrophic organisms in benthic biofilms. To test these effects, we characterized the composition of pigments when biofilms were exposed to dry conditions, and compared this to pigments measured after flow resumed, as well as to others measured from permanent streams in the same region. This comparison revealed important differences in pigmentary composition based on flow conditions. Active chlorophylls decreased exponentially with the duration and severity of the nonflow period, while chlorophyll degradation products and protective carotenoids increased. Streams experiencing longer and more severe nonflow periods showed the highest dissimilarities in their biofilm pigmentary composition, and this pattern was maintained after flow resumed. Our results pointed to duration of nonflowing periods as the major driver of pigmentary composition, regardless of whether these were interrupted or not by short intervals of water flows. Multivariate changes in pigmentary composition between sampling periods highlighted the influence of the long‐term hydrological history on the relative abundance of different taxonomic groups and their associated pigments. Overall, pigmentary fingerprints are informative of the biofilm capacity to resist water flow interruption and of their ability to recover after water flow returns.

Global prevalence of non-perennial rivers and streams.

Flowing waters have a unique role in supporting global biodiversity, biogeochemical cycles and human societies1-5. Although the importance of permanent watercourses is well recognized, the prevalence, value and fate of non-perennial rivers and streams that periodically cease to flow tend to be overlooked, if not ignored6-8. This oversight contributes to the degradation of the main source of water and livelihood for millions of people5. Here we predict that water ceases to flow for at least one day per year along 51-60percent of the world's rivers by length, demonstrating that non-perennial rivers and streams are the rule rather than the exception on Earth. Leveraging global information on the hydrology, climate, geology and surrounding land cover of the Earth's river network, we show that non-perennial rivers occur within all climates and biomes, and on every continent. Our findings challenge the assumptions underpinning foundational river concepts across scientific disciplines9. To understand and adequately manage the world's flowing waters, their biodiversity and functional integrity, a paradigm shift is needed towards a new conceptual model of rivers that includes flow intermittence. By mapping the distribution of non-perennial rivers and streams, we provide a stepping-stone towards addressing this grand challenge in freshwater science.

ТИПЫ ВЗАИМОСВЯЗИ ИНФРАСТРУКТУРЫ НАСЕЛЕННЫХ ПУНКТОВ С ЭРОЗИОННО-РУСЛОВЫМИ СИСТЕМАМИ

The results of studies of relationship between populated areas infrastructure (rural and urban) and erosional relief, gully erosion and channel processes are generalized. The formation of infrastructure and living conditions of the population depend on the degree of territory dissection by ravine-gully and river network, location of settlements on river banks – from small to the largest. Most of the settlements are confined to rivers and large gullies with a permanent watercourse, because these landforms supply water, ideal for industry development, energy production and transportation. At the same time, gully erosion and channel migration create certain risks for disfunction or destruction of operating facilities. With the growth of settlements and development of their technical and economic potential, the impact on certain elements and on the entire erosional relief is expanding, and the protection from hazardous gully erosion and channel processes is necessary. At different stages of their existence, settlements may completely depend on the relief, adjust to or transform erosion and channel processes, neutralizing their negative impact on human activities. Sustainable development of settlements depends on adequate choice of the territory, rational use of the erosional relief features, and accounting for probability of changes in the course of channels and gully formation. The study present the assessment and general classification of relationship of urban and rural settlements infrastructure (from small rural to the largest cities) with erosional relief, gully erosion and channel processes. Cities and rural settlements, subordinated to or suppressing erosional relief, rivers and channel processes are distinguished. The larger the city, the more complex these relationships are. Within the large city, different areas may refer to different types of interaction.

Late Aragonian mammal sites of Cuesta del Rey (Duero Basin, Burgos, Spain)

The Cuesta del Rey mammal sites located on the NE border of the Duero Basin are of great importance with regard to understand the general biostratigraphy of the basin, because Miocene mammal sites are extremely scarce in this area in comparison with the central part of the basin. The mammals identified in Cuesta del Rey-1 are: Eulipotyphla: cf. Miosorex sp.; Rodentia: Heteroxerus sp., Armantomys cf. tricristatus, Megacricetodon ibericus, Megacricetodon minor-Megacricetodon debruijni, Hispanomys sp. and Democricetodon sp. The Cuesta del Rey-1 rodent assemblage is characteristic of the end of the upper Aragonian (MN 7/8, end of the middle Miocene), equivalent to the local subzone G3 of the G zone. The presence of the genera Heteroxerus and Armantomys, and the predominance of Megacricetodon (with 80% of the total percentage of the minimum number of individuals of the micromammals) suggested an open savannah or steppe palaeoenvironment. The mammals identified in Cuesta del Rey-3 are: Rodentia: Megacricetodon cf. ibericus; Artiodactyla: Dorcatherium sp. and Listriodon cf. splendens. Dorcatherium sp. represents the first appearance of the Tragulidae family in the Duero Basin, suggesting the existence of permanent watercourses.

Пространственное распределение структурно-гидрографических характеристик речных систем бассейна озера Байкал

Analysis of structural and hydrographic characteristics of the structure of river systems and their interconnections was carried out for the future use in calculating runoff and the conditions of its formation for unexplored rivers. An annual normal and maximum water discharge observed in the 96 gauging sections of the standard observation network are hydrological basis. The research of river systems was carried out on the basis of topographic maps of scales of 1: 500 000 and 1: 200 000 and radar topographic surveys, which became the basis for constructing static and dynamic models of river systems. The static model is a totality of permanent watercourses and reflects the conditions of continuous flow. The system of impermanent and episodic watercourses is filled in the period of extreme flow. Аt this time, earlier element of the channel network without inflow become elements of a higher order. This model is dynamic. The study was conducted for the river systems of the Russian part of the Baikal basin. All parameters of river systems and their basins are divided into simple, structural and expositional classes, characterizing the conditions for the formation of thalwegs and runoff. The seven areas are identified which combine river systems when studying complex of the calculated parameters. The average structural module is a criterion for the distribution of the study territory into homogeneous area for the calculation of water discharge. The average structural module is determined by the local relation of annual normal water discharge on the total entropy of river systems. This relationship allows runoff calculations for watercourses that are not provided with hydrological information. In connection with this, a new stage of studies of the relationships between the characteristics of the structural class of the water-erosion network and the parameters of the river basin as an indicator of maximum aquifer ability arises.

Riparian or phreatophile woodland and shrubland vegetation in the Central Chilean biogeographic region: phytosociological study

The Mediterranean territory in Chile is an extensive area whose natural vegetation has suffered the impact of man-made activities far more severely than anywhere else in the country. Its northernmost section (the Atacama and Coquimbo regions) is characterised by ombroclimates that range from ultra-hyperarid to arid, and by highly irregular river courses with limited spaces for phreatophilic vegetation that have been exploited by humans as fertile farmlands. However, in the river valleys of the Central Chilean biogeographic province, where the ombroclimate is at least semiarid, there may be permanent watercourses that drain from the Andean mountain range towards the Pacific Ocean that contain representations of riparian or phreatophilic vegetation linked to riverbanks or alluvial terraces, in spite of the inevitable human influence. We studied the most conspicuous plant communities with the most highly developed biomass in these riparian environments, namely willow stands dominated by Salix humboldtiana and accompanied by some autochthonous woody species, in order to clarify their floristic composition and their correct ordination within the syntaxonomy of Chilean vegetation. The data collected suggest the existence of a phytosociological association: Otholobio glandulosi-Salicetum humboldtianae ass. nova, as the majority association in the Central Chilean province. Another possible association which replaces this (Baccharido salicifoliae-Myrceugenietum lanceolatae prov.) is also proposed in the transition to a humid ombroclimate and Temperate macrobioclimate.
 The floristic contents of these Chilean communities are compared with other associations dominated by Salix humboldtiana described for other territories bordering Chile: Argentina, Bolivia and Peru. However, given that they are all located in a Tropical macrobioclimate and their companion flora is therefore clearly different from the flora present in the Chilean communities, we propose the creation of a new phytosociological class to include these syntaxonomically: Mayteno boariae-Salicetea humboldtianae class. nova. This work also ascribes the association Tessario absinthioidis-Baccharidetum marginalis (representing a prior dynamic stage to Otholobio glandulosi-Salicetum humboldtianae) to the class Tessario integrifoliae-Baccharidetea salicifoliae.

Autumn drought drives functional diversity of benthic diatom assemblages of continental intermittent streams

Climate change is predicted to increase drought occurrence and severity in small continental watercourses. Here, we studied the structure and the functional diversity of benthic diatom assemblages in lowland intermittent and permanent watercourses of the Carpathian Basin. We assumed that the community structure of intermittent and permanent watercourses would be markedly different, and the functional diversity in both would be strongly influenced by autumn drought. We found that intermittent streams were primarily characterized by small-sized generalists and aerophilic taxa, while permanent watercourses were inhabited by large-sized planktic or fast moving groups. The functional richness was significantly lower in intermittent than in permanent streams. This decrease in the functional richness of benthic algal communities may negatively affect the functioning of lotic algal communities. We conclude that diatom assemblages in lowland intermittent watercourses are sensitive indicators of changes in ecosystem properties, and should be considered in appropriate evaluation and management of extreme climatic events on aquatic ecosystems.

Contours of the Past: LiDAR Data Expands the Limits of Late Pre-Columbian Human Settlement in the Santarém Region, Lower Amazon

ABSTRACTRecent studies have shown that pre-Columbian societies in the Amazon undertook significant landscape modifications, including earthworks. Our fieldwork has revealed that pre-Columbian settlements in the Santarém Region, Lower Amazon, were not limited to the vicinities of permanent water courses, as formerly often assumed. Instead, numerous archaeological sites, dating from ca. a.d. 1300 up to the time of European colonization in the seventeenth century, have been found in an upland area known as the Belterra Plateau, south of the present-day city of Santarém. These upland sites have been found to be associated with particular features in the landscape: cavities or depressions, known locally as “Poços de Água”. LiDAR data shows that a pattern of non-randomly distributed depressions extends far into the densely forested Tapajós National Forest (Flona-Tapajós), allowing us to suggest that the expansion of inland settlement extended considerably farther to the south than what has previously been established through conventional archaeological fieldwork.

Spread of Dermacentor reticulatus is associated with the loss of forest area

Changes in tick distribution and abundance are among the main drivers of the (re)emergence of transmitted pathogens. We aimed to uncover the reasons of the reported spread of Dermacentor reticulatus in Poland using a variety of proxies of environmental features, ground-measured temperature and remotely-sensed data of temperature and vegetation. Ground-measured temperature was recorded in 2013–2014, in sites where D. reticulatus presence (n = 16) or absence (n = 16) was confirmed. We specifically aimed to test whether changes in phenology of vegetation and the length of the growing season were correlated with field-derived data regarding the presence/absence of D. reticulatus. We also used categorical descriptions of the habitat to capture the vegetation patterns that might delineate the distribution of the tick. We demonstrated that temperature, phenology of vegetation and length of growing season have no correlation with the occurrence of D. reticulatus in Poland. There is, however, a clear association between the trends of the loss of forests and the presence of the tick. This parameter was two times higher at sites colonized by D. reticulatus in comparison to the sites where the population of the tick is not yet established. A spatial analysis demonstrated that the preferred territories for D. reticulatus are those of a highly fragmented landscape within a large patch of homogeneous vegetation, in the vicinity of permanent water courses or reservoirs.

Hydrological and Morphological Characteristics of Permanent Water Courses in kologrivski Forest Nature Reserve

Государственный природный заповедник «Кологривский лес» имени М. Г. Синицына расположен в Костромской области и был создан 21 января 2006 года с целью сохранения южно-таёжных природных комплексов Русской равнины. В настоящее время водотоки на территории заповедника являются слабоизученными, а исследования, проводимые на территории бывшего памятника природы и ныне существующего заповедника, имеют фрагментарный характер. Реки заповедника «Кологривский лес» характеризуются ярко выраженным весенним половодьем, летне-осенней низкой меженью, которая прерывается паводками, и зимней меженью. Глубина, ширина рек, расход воды изменяются как сезонно, так и на протяжении короткого периода при наличии обильных осадков. На Кологривском участке большинство рек характеризуются большими зарастающими открытыми малопроточными прибрежными участками и подвергаются значительному воздействию зоогенного фактора – деятельности бобров. Реки Мантуровского участка заповедника значительно отличаются от рек Кологривского участка как по гидрологическим, так и по морфологическим показателям.

Geomorphological Holocene events as deduced from lithological records of the fluvial basins of Dauria

A conjugate analysis of the processes of morphogenesis and sedimentation within small fluvial basins of Dauria revealed a rhythmic character of change of the Holocene processes which are combined into cycles of a different hierarchical level. It is shown that each cycle begins with an extreme phase of intense fluvial drift and delivery of matter from the system. The fluvial horizons comprise the lower part of deposits of the Holocene macrocycle in the Vesnyanka pad’ (a valley without a permanent watercourse). A disastrous fluvial drift was recorded repeatedly for the period 7–8.5 cal. ka and at the transition time from the Atlantic to Subboreal time. A normal zonal phase of integration of matter within the basins is exhibited by buried humus horizons of soils which give clear evidence of 1800-year cycles. A regional development in Dauria is recorded for the soils with the age of about 8, 6.4 and 4.6 as well as 1.2–1.4 cal. ka. The upper part of the deposits of each cycle is characterized by aeolian horizons of extreme arid phases. The profiles of proluvial trails are indicative of 130-year cycles. Based on results from studying buried soils, data of pollen analysis and radiocarbon dating of the deposits, we determined an enhancement in climate aridization for the last 10 ka and, in general, a decreased of the sedimentation and morphogenesis rate.

Evaluation of the Riverine Vegetation of Wadi Tafna in the Tlemcen Region (Western Algeria)

The vegetal landscape of riverine forest bordering streams of course, has a character linked to the high volatility of the intermittence of the latter. The watercourse temporary (wadis) are characterized by a vegetation and flora of Mediterranean type, (Tamarix, Nerium, Vitex, Phoenix...) in contrast to the permanent water courses at the level of the vegetation of leafy bed major European type, based mainly, poplar, ash or alder. In Western Algeria, the riverine forest vegetation is complex and fragile environments to several utilities. Latter by its diversity and these developed root systems will thus limit erosion of the banks and provide a stable structure to the formation. To identify and quantify the riverine forest on the Mediterranean coast in the South, especially in Western Algeria, we conducted surveys on land with an area of 100 m2 for each record, and then each species was conducted of two indices (abundance – dominance and sociability. The factorial analysis of correspondences has carried out us to classify these plant species according to the degree of salinity of the Wadi, the substrate and the slope. The riverine vegetation of wadi Tafna has been classified as follows: The so-called purely riverine forest vegetation is which are directly linked to the Wadi (in contact with the water and who are): Tamarix africana; Nerium oleander; Fragmites communis; Chenopodium album; Rumex bucephalophorus; etc. Vegetation low riverine forest is usually trained pre-forestieres species on siliceous substrate and are: Crateagus monogyna; Halimium halimifolium; Withania frutescens; Atriplex halimus; Acacia sp; Zygophyllum sp; Bryonia dioica; Calycotome intermedia; Suaeda sp. In conclusion, the inadequacy of our knowledge of the biology and ecology of vegetation riverine forest of our region requires multiscale study and multidisciplinary in order to better understand the structure and operation of all hydro-system. These phyto-sociological and phyto-dynamic data lead to classify these plants according to ecological factors of their site and understand its evolution and diversity through the study area.