Occurrence In Ponds Research Articles

Impact of Land Use Type on Macrophyte Occurrence in Ponds in a Changing Climate

Small ponds are essential environmental elements that perform many ecological functions. We tried to answer whether the macrophytes in ponds may be influenced by environmental factors and the neighboring areas’ land-use type. We also tried to determine the trend of changes in the ponds’ depth and size over the decade (2008–2018). The research was carried out on eight ponds in four types of land use (agricultural, horticultural, urban, and industrial areas). The study covered ponds’ morphometric parameters, macrophytes’ occurrence, and physicochemical water parameters. All data collected were statistically processed using CCA, linear regression, and Pearson’s correlation. The results indicated a continuous tendency for the ponds’ size and depth to decrease, particularly in urbanized areas. During the study, most macrophytes’ genera increased their area. Our research allowed us to separate two homogeneous groups of ponds in terms of environmental conditions. The first was horticultural area ponds, for which higher nutrient concentrations in water were determined. Those ponds were inhabited by Ceratophyllum and Sparganium genera. The second was urban and industrial area ponds characterized by higher water temperature, transparency, pH, and were richer in Mg and Ca. Carex, Potamogeton, and Schoenoplectus genera preferred such conditions.

Ponding time in infiltration process for different land use

Ponding time is the period from the beginning of rainfall/infiltration until the occurrence of ponding. This paper aims to determine the infiltration rate and ponding time on different land uses, such as open fields, residential, agriculture, and vegetation. This research was conducted in one of the watersheds in the Brantas River Basin, namely the Lesti River Basin, which is administratively included in the Malang Regency, East Java. The Lesti River is one of the tributaries of the Brantas River, which originates around Mount Semeru, a very intensive area for planting rice, sugar cane, and coffee. Infiltration data were collected at 35 points using a double-ring infiltrometer spread across the Lesti watershed with Andosol, Mediterranean, and Regosol soil types. At the same time, ponding time was obtained from infiltration measurements in the field using the flooding method. The physical properties of the soils were tested in the laboratory to obtain water content, porosity, and bulk density values. This study resulted in the infiltration rate and ponding time for each land use and shows how the physical properties of the soil affect the ponding time.

First Perceptions of Hydroperiod Mapping and Assessment of Shallow Waters in Coastal Landscapes by Drone-Based Monitoring Activities: A Remote-Sensing and GIS Approach

Beyond the importance of ponds for aquatic and terrestrial life, pond networks seem to be crucial to providing a vital spatial resource in response to global climate change for all migrating and spreading taxa. Additionally, ponds offer sustainable solutions to issues of concern in water management, such as nutrient retention, rainfall interception, or carbon sequestration. Although the ecological role of shallow waters seems clear, significant work must be performed to set future guidelines and actions towards their conservation. The main aims of the present study are to (i) georeference all small temporary wetlands within the Tyrrhenian central Italy coastal area, (ii) evaluate their hydroperiod, and (iii) calculate their surface size variability. We found 137 wetlands, 53 of which were temporary and contained listed habitats. Each wetland’s status was assessed in relation to land use and proximity to stressors (e.g., urban centres, railways, roads) while observing the relationship between pond occurrence, lithology, and permeability. Amongst the detected wetlands, we selected and monitored 21 temporary ponds (homogeneously distributed within the study area) for 12 months using images collected by the non-professional drone Parrot Bebop 2. All images were then acquired in ArcGIS to georeference all temporary ponds. The analysis confirmed that the majority of the surveyed ponds are in close proximity to roads and tracks, which might have significant impacts on the preservation of such fragile habitats. Moreover, despite the wide variability of hydroperiod duration, the greater part of the pools fill with water in autumn and dry in summer, in alignment with the Mediterranean climate. This preliminary study allowed for the creation of the first temporary ponds’ database, which is useful for monitoring their status in central Italy and planning further studies to assess eventual detrimental effects caused by human-mediated activities.

The Causes of Debris-Covered Glacier Thinning: Evidence for the Importance of Ice Dynamics From Kennicott Glacier, Alaska

The cause of debris-covered glacier thinning remains controversial. One hypothesis asserts that melt hotspots (ice cliffs, ponds, or thin debris) increase thinning, while the other posits that declining ice flow leads to dynamic thinning under thick debris. Alaska’s Kennicott Glacier is ideal for testing these hypotheses, as ice cliffs within the debris-covered tongue are abundant and surface velocities decline rapidly downglacier. To explore the cause of patterns in melt hotspots, ice flow, and thinning, we consider their evolution over several decades. We compile a wide range of ice dynamical and mass balance datasets which we cross-correlate and analyze in a step-by-step fashion. We show that an undulating bed that deepens upglacier controls ice flow in the lower 8.5 km of Kennicott Glacier. The imposed velocity pattern strongly affects debris thickness, which in turn leads to annual melt rates that decline towards the terminus. Ice cliff abundance correlates highly with the rate of surface compression, while pond occurrence is strongly negatively correlated with driving stress. A new positive feedback is identified between ice cliffs, streams and surface topography that leads to chaotic topography. As the glacier thinned between 1991 and 2015, surface melt in the study area decreased, despite generally rising air temperatures. Four additional feedbacks relating glacier thinning to melt changes are evident: the debris feedback (negative), the ice cliff feedback (negative), the pond feedback (positive), and the relief feedback (positive). The debris and ice cliff feedbacks, which are tied to the change in surface velocity in time, likely reduced melt rates in time. We show this using a new method to invert for debris thickness change and englacial debris content (∼0.017% by volume) while also revealing that declining speeds and compressive flow led to debris thickening. The expansion of debris on the glacier surface follows changes in flow direction. Ultimately, glacier thinning upvalley from the continuously debris-covered portion of Kennicott Glacier, caused by mass balance changes, led to the reduction of flow into the study area. This caused ice emergence rates to decline rapidly leading to the occurrence of maximum, glacier-wide thinning under thick, insulating debris.

Use of aquaculture ponds by globally endangered red-crowned crane (Grus japonensis) during the wintering period in the Yancheng National Nature Reserve, a Ramsar wetland

Conversion of natural wetlands to artificial wetlands is a global phenomenon that leads to loss of natural habitats for waterbirds, while these alternative wetlands may buffer the adverse effects of natural wetlands loss by providing waterbirds with suitable habitats. Yancheng National Nature Reserve (YNNR), a Ramsar wetland in China, is the largest wintering area for the globally endangered red-crowned crane (Grus japonensis). A remarkable part of natural wetlands within the YNNR has been reclaimed into aquaculture ponds in recent decades. In order to better understand the utilization of aquaculture pond by cranes and identify beneficial management actions, we investigated the wintering crane occurrence in ponds and quantified pond characteristics as mainly influence factors from November to March in 2017–2018 and 2018–2019. A total of 198 ponds were measured (91 in 2017–2018 and 107 in 2018–2019), out of which 42 ponds were found to be used by 48 groups of cranes (16 in 2017–2018 and 32 in 2018–2019). Family groups with 2–4 individuals of cranes were mostly encountered (91.7%) of all the group types. Wintering crane abundance in the aquaculture ponds was higher in 2018–2019 (105 individuals) than that in 2017–2018 (59 individuals). Five factors including water depth, species abundance, species richness, structures and distance to road were identified to influence use of ponds by cranes. However, crane occurrence was significantly associated with only water depth. This study recognized aquaculture ponds as a potential habitat for red-crowned crane. Efforts should be channeled into the sustainable development and maintenance of aquaculture ponds. More specifically, we recommended appropriate management practices to benefit wintering cranes by sequential harvesting of aquaculture ponds, maintaining aquaculture ponds in the buffer zone and keeping the water at a low level.

3. Local and Landscape-Scale Variables Influencing the Use of Ponds by Wood Frogs (Lithobates sylvaticus) in the Shakwak Valley, Yukon

A global decline in amphibian population numbers has generated a large body of research focused on amphibian habitat selection and species diversity conservation. The purpose of this study was to analyze the significance of both local and landscape-scale variables on wood frog (Lithobates sylvaticus) pond habitat selection in the Shakwak Trench in Yukon, Canada. Presence or absence of wood frogs was used to determine pond occurrence values for 40 different ponds. Independent local variables were collected in the field and through the use of Geographic Information Systems (GIS). Landscape variables were derived with GIS and were analyzed under a 1000m buffer around the perimeter of the study ponds. Pond perimeter and dominant perimeter vegetation were significant local variables. Small ponds with a dominant sedge vegetation types seemed to be selected over larger ponds. Large lake area in the landscape buffers had a significant negative relationship for wood frog habitat selection. Significant variables in this study are similar to those in previous studies or can be linked to other important variables such as pond hydroperiod and total forested area. Results should be considered to act as preliminary findings in a much more comprehensive and complete future amphibian habitat selection study of the area.

Contamination of Detained Sediment in Sustainable Urban Drainage Systems

Adsorption is a key water pollution remediation measure used to achieve stormwater quality improvement in Sustainable urban Drainage Systems (SuDS). The level of contamination of detained sediment within SuDS assets is not well documented, with published investigations limited to specific contaminant occurrence in ponds, wetlands or infiltration devices (bioretention cells) and generally focused on solute or suspended sediment. Guidance on contamination threshold levels and potential deposited sediment contamination information is not included in current UK SuDS design or maintenance guidance, primarily due to a lack of evidence and understanding. There is a need to understand possible deposited sediment contamination levels in SuDS, specifically in relation to sediment removal maintenance activities and potential impact on receiving waterways of conveyed sediment. Thus, the objective of the research presented herein was to identify what major elements and trace metals were observable in (the investigated) SuDS assets detained sediment, the concentration of these major elements and trace metals and whether they met/surpassed ecotoxicity or contaminated land thresholds. The research presented here provides evidence of investigated SuDS sediment major element and trace metal levels to help inform guidance and maintenance needs, and presents a new methodology to identify the general cause (anthropocentric land use) and extent of detained SuDS fine urban sediment contamination through use of a contamination matrix.

Landscape context influences chytrid fungus distribution in an endangered European amphibian

AbstractWildlife disease is an emerging threat to biodiversity. The amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd), which causes the disease chytridiomycosis, has been documented in over 500 amphibian species globally. Understanding conditions under which amphibians are vulnerable to Bd is important for evaluating species risk and developing surveillance strategies. Here, we investigate the spatial distribution of Bd infection in the ephemeral pond‐breeding yellow‐bellied toad Bombina variegata, a species of high conservation concern in the European Union. We sampled 550 toads from 60 ponds in a traditional agricultural landscape in Southern Transylvania, Romania. Overall, Bd prevalence was low in B. variegata, but infected toads were widely dispersed through the landscape and were found in a quarter of all sampled ephemeral ponds. At the pond level, increased Bd occurrence was associated with short distances to perennial water sources and high forest cover. These findings suggest that perennial water sources may act as source habitat for Bd, with amphibian movements resulting in Bd spillover into ephemeral ponds. Increased Bd occurrence in ponds surrounded by high levels of forest cover is likely related to cooler and wetter conditions that are more favourable for Bd. Throughout the study landscape, patchy environmental suitability for Bd appears to restrict the pathogen to a subset of B. variegata habitat. Ephemeral ponds in open landscapes, without nearby perennial habitat, likely provide an environmental refuge from Bd, where the risk of infection is low. From a conservation perspective, these findings highlight the importance of maintaining ephemeral ponds in open landscapes, but these are currently threatened by land‐use change.

Artificial water points for wildlife management facilitate the spread of red swamp crayfish (Procambarus clarkii)

The red swamp crayfish (Procambarus clarkii) has been widely introduced into aquatic systems all around the world, triggering multiple impacts. In Donana Natural Area, Abalario and the Biological Reserve of Donana, Spain (one of the most important biodiversity reserves in Europe), the red swamp crayfish was first introduced in 1974 and expanded its range quickly through marsh habitat, but distributed more slowly throughout scrubland ponds. Water persistence, salinity, and substrate can condition the presence of the species in the wild. Before the creation of the Natural Area and the Biological Reserve of Donana, farmers dug artificial water points in some scrubland ponds to provide water throughout the year for livestock. Once declared a protected area, managers assumed control of the maintenance of the park and opened new water points as a wildlife management tool. The aim of the study presented here was to determine the environmental conditions that favor the spread of crayfish in the temporal ponds of Donana and whether the occurrence of water points increases the spread of crayfish. For this purpose, we sampled crayfish using a sweep net in 60 randomly selected ponds in two different areas of Donana. Crayfish occurrence was significantly related to the presence of seasonal streams connecting the ponds with refuge areas and to the presence of artificial water points within the pond. The probability of occurrence of red swamp crayfish in a pond without seasonal streams was more than 5 times lower than that in a pond with seasonal streams. The probability of crayfish occurrence in ponds without artificial water points was 2.5 times lower than that in ponds with artificial water points. We review the advantages and disadvantages of water points as a management tool.

A STUDY ON PONDING TIME AND INFILTRATION CAPACITY DURING STEADY RAINFALL

Natural rainfall has the variation in rainfall intensity during its event. However, the various infiltration models are subjected to rainfall intensities that are higher than the infiltration capacity of the soil at a given location. Diskin and Nazimov (J. Hydrol., 172: 313-330, 1995) proposed recently the infiltration model which is a simple conceptual model and can express the relationship between rainfall intensity and ponding time.‘Ponding time’ is the period from the beginning of rainfall until the occurrence of ponding. This model also can compute the variation in the infiltration capacity for constant or variable rainfall rates. A simple conceptual model is valuable for carrying out the stormwater runoff analysis.The purpose of this paper is to investigate the ponding time and the infiltration capacity for field infiltration data measured using a rainfall simulator under steady rainfall and to evaluate the above infiltration model proposed by Diskin and Nazimov. Comparison of the model calculations with experimental data shows reasonably good for the relationship between rainfall intensity and ponding time and excellent agreement for the infiltration decay curves.