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Success stories are rare in conservation science, hindered also by the research-implementation gap, where scientific insights rarely inform practice and practical implementation is rarely evaluated scientifically. Amphibian population declines, driven by multiple stressors, are emblematic of the freshwater biodiversity crisis. Habitat creation is a straightforward conservation action that has been shown to locally benefit amphibians, as well as other taxa, but does it benefit entire amphibian communities at large spatial scales? Here, we evaluate a landscape-scale pond-construction program by fitting dynamic occupancy models to 20 y of monitoring data for 12 pond-breeding amphibian species in the Swiss state Aargau, a densely populated area of the Swiss lowlands with intensive land use. After decades of population declines, the number of occupied ponds increased statewide for 10 out of 12 species, while one species remained stable and one species further declined between 1999 and 2019. Despite regional differences, in 77% of all 43 regional metapopulations, the colonization and subsequent occupation of new ponds stabilized (14%) or increased (63%) metapopulation size. Likely mechanisms include increased habitat availability, restoration of habitat dynamics, and increased connectivity between ponds. Colonization probabilities reflected species-specific preferences for characteristics of ponds and their surroundings, which provides evidence-based information for future pond construction targeting specific species. The relatively simple but landscape-scale and persistent conservation action of constructing hundreds of new ponds halted declines and stabilized or increased the state-wide population size of all but one species, despite ongoing pressures from other stressors in a human-dominated landscape.

Over the past century, millions of ponds have been constructed on farms across the eastern Great Plains of the US. Although these ponds have been built to provide water for livestock and reduce soil erosion, they also serve as habitat for native species in agricultural landscapes that historically lacked natural wetlands. Because this role in supporting biodiversity has been chronically underappreciated, approaches to managing these ponds effectively for conservation remain poorly developed. Here, we discuss the historical context of pond construction, the role of ponds in agriculture, and their present distribution across the “American Pond Belt”. On the basis of our review of their ecology and threats, we contend that farm pond conservation should focus on enhancing pondscapes – networks of ponds encompassing a range of successional stages – to support the broadest array of biodiversity at a landscape scale. We also highlight the role of scientists, agency personnel, policy makers, and landowners in the future conservation of pondscapes in the Great Plains.

Inland waters play a major role in global greenhouse gas (GHG) budgets. The smallest of these systems (i.e., ponds) have a particularly large—but poorly constrained—emissions footprint at the global scale. Much of this uncertainty is due to a poor understanding of temporal variability in emissions. Here, we conducted high‐resolution temporal sampling to quantify GHG exchange between four temperate constructed ponds and the atmosphere on an annual basis. We show these ponds are a net source of GHGs to the atmosphere (564.4 g CO2‐eq m−2 yr−1), driven by highly temporally variable diffusive methane (CH4) emissions. Diffusive CH4 release to the atmosphere was twice as high during periods when the ponds had a stratified water column than when it was mixed. Ebullitive CH4 release was also higher during stratification. Building ponds to favor mixed conditions thus presents an opportunity to minimize the global GHG footprint of future pond construction. Plain Language Summary Ponds are an important contributor to global greenhouse gas emissions, but there is still much uncertainty associated with global emissions estimates. To clarify this uncertainty, we investigated seasonal patterns of greenhouse gas emissions from four constructed ponds in a temperate region of the northeastern United States. We found that methane made up most of pond greenhouse gas emissions on an annual basis, leading the ponds to be a net source of greenhouse gases to the atmosphere. Methane and carbon dioxide exchange between ponds and the atmosphere followed clear seasonal patterns, with highest rates of methane release to the atmosphere during warm summer months. Ponds consumed carbon dioxide during warm months when aquatic plants were growing rapidly. We also found high variability in methane and carbon dioxide emissions over weekly time periods that was associated with whether the water column in the pond was mixed or stratified. When ponds were stratified, methane emissions were higher than during mixed conditions, possibly due to low availability of oxygen near sediments where methane is produced by micro‐organisms that require low oxygen conditions. These results provide a path forward to better estimating pond greenhouse gas emissions at a global scale. Key Points Constructed ponds are a net source of global greenhouse gass to the atmosphere on annual basis CO2 and CH4 exchange between ponds and the atmosphere show strong seasonal trends, with CH4 highly variable within season Summertime diffusive CH4 release dominates annual emissions budget

The main challenge in extracting coastal aquaculture ponds is how to weaken the influence of the “same-spectrum foreign objects” effect and how to improve the definition of the boundary and accuracy of the extraction results of coastal aquaculture ponds. In this study, a recognition model based on the U2-Net deep learning model using remote sensing images for extracting coastal aquaculture ponds has been constructed. Firstly, image preprocessing is performed to amplify the spectral features. Second, samples are produced by visual interpretation. Third, the U2-Net deep learning model is used to train and extract aquaculture ponds along the coastal region. Finally, post-processing is performed to optimize the extraction results of the model. This method was validated in experiments in the Zhoushan Archipelago, China. The experimental results show that the average F-measure of the method in the study for the four study cases reaches 0.93, and the average precision and average recall rate are 92.21% and 93.79%, which is suitable for extraction applications in aquaculture ponds along the coastal region. This study can quickly and accurately carry out the mapping of coastal aquaculture ponds and can provide technical support for marine resource management and sustainable development.

Due to the inadequate removal rates of drug residues in wastewater treatment plants (WWTP), the transition of these compounds into the environment has become a serious environmental problem for ecosystems and public health. In this study, occurrence, fate, and removal of widely consumed two antibiotics, ciprofloxacin (CIP) and sulfamethoxazole (SMX), selected from fluoroquinolone and sulfonamide groups, respectively were investigated in three different types of full-scale WWTPs located in Turkey. In this context, three WWTPs consisting of advanced biological treatment (large-scale), wastewater stabilization pond (WSP) (medium-scale), and constructed wetland (CW) (small-scale) were selected. While the detected influent concentrations of CIP in WWTPs ranged between the 218.6 and 2733.5 ng/L, maximum influent concentration for SMX in the same plants was determined as 179.7 ng/L. On the other hand, although it was detected at higher concentrations in raw wastewater, CIP was significantly removed in all WWTPs with a removal efficiency ranging from >77.1 to >98.2%. However, SMX showed quite different behaviors depending on the applied wastewater treatment processes in WWTPs in terms of total removal achieved. While treated in WSP well enough (>72.2%), a serious negative removal efficiency (−133.4%) was achieved for SMX in the WWTP having advanced biological treatment. Best removal performance obtained for the both antibiotic compounds among the investigated WWTPs was the medium-scale WSP consisting of anaerobic and facultative stabilization ponds, consecutively. This situation also supported the idea that WWTPs which are operated with higher solid retention time (SRT) and hydraulic retention time (HRT) contribute positively in the removal of antibiotic compounds.

Nowadays, GIS and remote sensing techniques are effectively used to find groundwater prospect zones in various troublesome landscapes throughout the world. In the present work, groundwater potential zonation mapping was carried out for the Vattamalaikarai River basin in South India by overlaying ten thematic maps such as soil, drainage density, lineament density, geology, slope, land use/land cover, geomorphology, topographic position index, rainfall and groundwater level by giving appropriate weightages to each significant parameter with respect to its influence on groundwater. As the basin mainly depends on the groundwater resources, it is necessary to assess the groundwater prospect for the better management of aquifer system. Groundwater potential zonation map illustrates that more than 50% of the basin region falls under moderate to low groundwater potential category. Highly influential thematic layers were integrated to generate groundwater recharge zonation map. Based on this output, artificial recharge sites were selected to replenish the groundwater resources in the basin. Three check dam sites were suggested across the third- and fourth-order streams. Four suitable sites for the construction of percolation ponds and ten locations for the construction of recharge pits were also identified. Four injection well sites were recommended to augment groundwater in the aquifer present under the black cotton soil regions in the western part of the basin.

Millions of farm ponds have been constructed in agricultural landscapes around the globe. These ponds are built to support a variety of functions, including erosion control, cattle grazing, and recreational fishing, but their role as breeding habitat for amphibians remains poorly understood. We addressed this knowledge gap by studying farm ponds in the eastern Great Plains of the United States, a pond-dense region dominated by agriculture. We used field surveys and occupancy modeling to identify the important biophysical components of amphibian habitat and to assess the species-specific effects of cattle and fish presence on breeding occupancy. We next used a chronosequence to determine whether pond renovation, which often occurs when ponds are about 40 yr old, threatens the development of amphibian habitat. Nine amphibian species bred in the farm ponds that we surveyed, and the relationship between breeding occupancy and habitat variables varied by species. We found that the pH conditions associated with amphibian breeding occupancy were significantly more likely to occur in older ponds (>50 yr old). Emergent vegetation cover was also associated with increased breeding probability and rarely reached high levels in newer ponds. Since the older ponds with suitable habitat are at an age where renovation is likely needed to restore their agricultural function, this habitat may be at risk. We suggest that conservation of amphibians in farm ponds in the United States will require adopting renovation and management practices that balance the multiple uses of these sites and maintain a mosaic of pond successional states.

A bstract Three years ago, we proposed free off-shell models for N = 2 superconformal higher-spin multiplets in arbitrary conformally flat backgrounds, constructed conserved conformal higher-spin supercurrents for a massless hypermultiplet, and sketched the Noether procedure to generate its cubic couplings to the superconformal higher-spin multiplets. This paper is devoted to completing the Noether procedure. Specifically, we: (i) describe the unique off-shell primary extensions of the conformal higher-spin supercurrents; (ii) embed the off-shell superconformal prepotentials into primary unconstrained isotwistor multiplets; and (iii) present the unique gauge transformations of the hypermultiplet and the isotwistor prepotentials. An extension of the Noether procedure beyond the cubic level is also sketched, following the earlier N = 1 superconformal approach developed by the authors and Ponds in 2022. Our construction is based on making use of the polar hypermultiplet within the projective-superspace setting.

The freshwater calanoid copepod, Arctodiaptomus dorsalis , native to countries around the Caribbean Sea and the Gulf of Mexico, is now widely distributed and dominant in fresh waterbodies on the Island of Hawai‘i. We show that it makes diapausing eggs, providing a likely mechanism enhancing dispersal both across the Pacific Ocean and among local waterbodies. Dense populations of A. dorsalis have been found in one lake and 10 of 15 sampled ponds. In two years of biweekly sampling of two permanent ponds it was abundant to the near exclusion of other zooplankton. Although these two ponds are located only 55 m apart and connected by an intermittent stream, the prevalence and seasonal timing of diapause differed markedly between populations. The diapause differences appear to be local adaptation within the 34 years since pond construction: the population with greater diapause experiences greater fluctuations in pond volume, principally during the dry season (May to October), with timing and prevalence of diapause corresponding well with a model of optimal trait expression. The other population with very little diapause experiences only minor fluctuations in pond volume. Rapid local adaptation following introduction likely enhances the species’ success in Hawai‘i. Characteristics of A. dorsalis on Hawai‘i Island consistent with calling it “invasive” include that it is non-native, introduced by humans, invasive elsewhere globally, spreading locally, with a dispersing phenotype (diapausing eggs), reproduces and survives where present, and is nearly always abundant and dominant. An impact on the planktonic food web remains conjecture, but is likely based on its local dominance and what is known of its feeding ecology elsewhere.

Small artificial waterbodies are larger emitters of carbon dioxide (CO2) and methane (CH4) than natural waterbodies. The Intergovernmental Panel on Climate Change (IPCC) recommends these waterbodies are accounted for in national emission inventories, yet data is extremely limited for irrigated landscapes. To derive a baseline of their greenhouse gas footprint, we investigated 38 irrigation farm dams in horticulture and broadacre cropping in semi-arid NSW, Australia. Dissolved CO2, CH4, and nitrous oxide (N2O) were measured in spring and summer, 2021–2022. While all dams were sources of CH4 to the atmosphere, 52% of irrigation farm dams were sinks for CO2 and 70% were sinks for N2O. Relationships in the linear mixed effect models indicate that CO2 concentrations were primarily driven by dissolved oxygen (DO), ammonium, and sediment carbon content, while N2O concentration was best explained by an interaction between DO and ammonium. Methane concentrations did not display any relationship with typical biological variables and instead were related to soil salinity, trophic status, and size. Carbon dioxide-equivalent emissions were highest in small (< 0.001 km2) dams (305 g CO2-eq m−2 season−1) and in those used for recycling irrigation water (249 g CO2-eq m−2 season−1), with CH4 contributing 70% of average CO2-eq emissions. However, irrigation dams had considerably lower CH4 emissions (mean 40 kg ha−1 yr−1) than the IPCC emission factor (EF) of 183 kg CH4 ha−1 yr−1 for constructed ponds and lower N2O EF of 0.06% than the indirect EF for agricultural surface waters (0.26%). This synoptic survey reveals existing models may be severely overestimating (4–5 times) farm dam CH4 and N2O emissions in semi-arid irrigation areas. Further research is needed to define these artificial waterbodies in emissions accounting.