Effects of multiple temperature variations on nitrogen removal and microbial community structure in tidal flow constructed wetlands.

Tidal-flow constructed wetlands (TFCWs) provide distinct advantages for nitrogen removal by enhancing microbial activity through dynamic water level fluctuations. However, effects of temperature on nitrogen transformation processes and microbial community dynamics in TFCWs remain unclear. We analyzed the effects of TFCWs on nitrogen transformation and microbial community structure under different temperature conditions (23, 16, 12, and 8 °C) through 140 days of temperature-controlled experiments.

Functional characteristics and habitat suitability of threatened birds in northeastern China.

Northeast China, rich in natural resources and diverse biodiversity, boasts a unique habitat for threatened bird species due to its remote location and perennial cold climate. An analysis assessed the adaptability of these species using data on their geographic distribution and functional traits collected through database queries. The results revealed that threatened bird species share similar functional traits and a stronger phylogenetic signal (Blomberg mean  = 0.

Projecting the response of ecological risk to land use/land cover change in ecologically fragile regions.

Anthropogenic activities have dramatically altered land use/land cover (LULC), leading to ecosystem service (ES) degradation and further ecological risks. Ecological risks are particularly serious in ecologically fragile regions because trade-offs between economic development and ecological protection are prominent. Thus, ways in which to assess the response of ecological risks to LULC change under each development scenario in ecologically fragile regions remain challenging.

Forest swamp succession alters organic carbon composition and survival strategies of soil microbial communities.

Forest swamp ecosystems plays crucial role in the global carbon cycle. However, the effects of forest swamp succession on soil organic matter (SOM) and microbial community structure remain unclear. To determine the drivers of SOM change and soil microbial communities in forest swamp succession, a 'space instead of time' approach was used.

Interactions between phenanthrene and polystyrene micro/nano plastics: Implications for rice (Oryza sativa L.) toxicity.

Micro/nano plastics (MPs/NPs) are widely distributed and are one of the global pollutants of current concern. Micro/nano plastics can adsorb a variety of persistent organic pollutants, and different particle sizes and surface charges affect the biological effects of MPs/NPs. Therefore, how the compound pollution of MPs/NPs with different particle sizes and organic pollutants produces toxic effects on plants needs to be further studied.

Water quality pollution assessment and source apportionment of lake wetlands: A case study of Xianghai Lake in the Northeast China Plain.

Surface water pollution has always posed a serious challenge to water quality management. Improving water quality management requires figuring out how to comprehend water quality conditions scientifically and effectively as well as quantitatively identify regional pollution sources. In this study, Xianghai Lake, a typical lake-type wetland on the Northeast China Plain, was taken as the research area.

Molecular mechanisms of toxicity and detoxification in rice (Oryza sativa L.) exposed to polystyrene nanoplastics.

Nanoplastics (NPs) are an emerging threat to higher plants in terrestrial ecosystems. However, the molecular of NP-related phytotoxicity remains unclear. In the present study, rice seedlings were exposed to polystyrene (PS, 50 nm) NPs at 0, 50, 100, and 200 mg/L under hydroponic conditions to investigate the induced physiological indices and transcriptional mechanisms.

Toxicological effects and transcriptome mechanisms of rice (Oryza sativa L.) under stress of quinclorac and polystyrene nanoplastics.

The absorption and accumulation of nanoplastics (NPs) by plants is currently attracting considerable attention. NPs also tend to adsorb surrounding organic pollutants, such as pesticides, which can damage plants. However, molecular mechanisms underlying the phytotoxicity of NPs are not sufficiently researched.

Integration of MFC reduces CH, NO and NH emissions in batch-fed wetland systems.

The combination of microbial fuel cells (MFCs) with constructed wetlands (CWs) for enhancing water purification efficiency and generating bioelectricity has attracted extensive attention. However, the other benefits of MFC-CWs are seldom reported, especially the potential for controlling gaseous emissions. In this study, we have quantitatively compared the pollutant removal efficiency and the emission of multiple gases between MFC-CWs and batch-fed wetland systems (BF CWs).

Response of vegetation variation to climate change and human activities in semi-arid swamps.

Vegetation is a sensitive factor in marsh ecosystems, which can provide nesting sites, foraging areas, and hiding places for waterfowl and can affect their survival environment. The Jilin Momoge National Nature Reserve, which consists of large areas of marshes, is located in the semi-arid region of northeast China and is an important stopover site for the critically endangered species of the Siberian Crane (). Global climate change, extreme droughts and floods, and large differences in evaporation and precipitation in this region can cause rapid vegetation succession.

Effects of individual and combined polystyrene nanoplastics and phenanthrene on the enzymology, physiology, and transcriptome parameters of rice (Oryza sativa L.).

Owing to their wide distribution, easy production, and resistance to degradation, microplastics (MPs) represent a globally emerging group of pollutants of concern. Furthermore, their decomposition can result in the generation of nanoplastics (NPs), which cause further environmental issues. Currently, the impact of the combination of these plastics with other organic pollutants on crop growth remains poorly investigated.

Effects of polystyrene nanoplastics with different functional groups on rice (Oryza sativa L.) seedlings: Combined transcriptome, enzymology, and physiology.

Plastic particles originate from the daily use of plastics and have become a new form of pollutant. However, the effects of nanoplastics (NPs) on higher plants remain largely unclear, thus requiring further research. In this study, rice plants were exposed to polystyrene (PS) NPs with different functional groups to determine their toxicity.

Shift in nitrogen transformation in peatland soil by nitrogen inputs.

Inputs of nitrogen (N) to peatlands in the form of fertilizers have rapidly increased due to the intensification of agricultural systems, impacting ecological processes, and the carbon storage function of peatland. However, detailed information on the impacts of long-term N inputs on the individual steps of N transformation processes in peatland soils still needs to be fully understood. We investigated N mineralization and nitrification rates as well as nitrite dependent anaerobic methane oxidation (n-damo), anaerobic ammonium oxidation (anammox), denitrification, and dissimilatory nitrate reduction to ammonium (DNRA) in a peatland affected by N inputs for >50 years, using isotope tracing technique and quantitative PCR.

Author Correction: Snow depths' impact on soil microbial activities and carbon dioxide fluxes from a temperate wetland in Northeast China.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Snow depths' impact on soil microbial activities and carbon dioxide fluxes from a temperate wetland in Northeast China.

Snow depth may have a complex influence on carbon cycling in winter. Here we set up a field experiment to investigate how different snow depths (0 cm, 60 cm, 90 cm) influenced carbon dioxide (CO) in a wetland. The mean ± standard error of CO emissions under snow addition treatments (60 cm and 90 cm snow depths) were 0.

Enhancing Cd(II) sorption by red mud with heat treatment: Performance and mechanisms of sorption.

Red mud is a waste generated from the aluminum industry in large quantities. The potential of red mud as a sorbent for beneficial reuse has been the focus of research efforts. However, the limited sorption capacity of red mud has hindered its applications in the removal of environmental pollutants.

Characteristics of Cadmium Sorption by Heat-Activated Red Mud in Aqueous Solution.

Red mud as a waste material is produced in large quantities by the aluminum industry. Heat activation has been used to enhance sorption capacity of red mud for its beneficial reuse as an effective sorbent. In this study, heat-activated red mud (HARM) was investigated for its Cd(II) sorption capacity under various process conditions (Cd concentration, pH and contact time) using response surface methodology (RSM).

Effect of planting and fertilization on lead partitioning in dredged sediment.

Dredging has been practiced to remove sediment impacted by persistent contaminants, such as heavy metals. Of these metals, lead (Pb) is of particular concern due to its toxicity. Therefore, dredged sediment containing Pb requires further mitigation.

Slow stamen movement in a perennial herb decreases male-male and male-female interference.

Approximately 80 % of angiosperm species produce hermaphroditic flowers, which face the problem of malemale sexual interference (one or more anthers gets in the way of disseminating pollen from other anthers) or malefemale sexual interference (the pistil interferes with disseminating pollen from the anthers by preventing the anther from touching a pollinator, or the anther prevents pollinator from depositing outcross pollen on the stigma). Slow stamen movement in hermaphrodite flowers has been interpreted as an adaptation for reducing malemale sexual interference. Using slow stamen movement in (Caryophyllaceae), this study presents new evidence that this phenomenon can reduce both malemale and malefemale sexual interference.

Using C isotopes to explore denitrification-dependent anaerobic methane oxidation in a paddy-peatland.

Peatlands are organic-matter-rich but nitrogen-limited natural systems, the carbon/nitrogen (C/N) status of which are subject to increasing exposure from long-term nitrate (NO) fertilizer inputs and atmospheric nitrogen (N) deposits. To manage and protect these unique environments, an improved understanding of denitrification-dependent anaerobic oxidation of methane (DAMO) in peatlands is needed. In this study, we used stable isotope measurements and incubation with NO additions to facilitate an investigation and comparison of the potential DAMO rates in a paddy-peatland that has been influenced by N fertilizer over 40 years and an undisturbed peatland in northeast China.

The Spatial Distribution of Nitrogen Removal Functional Genes in Multimedia Constructed Wetlands for Wastewater Treatment.

The real-time polymerase chain reaction was used to quantitatively evaluate distribution patterns and nitrogen removal pathways of the amoA, nxrA, narG, napA, nirK, qnorB, nosZ, nas, and nifH genes and 16S rRNA in anaerobic ammonia oxidation bacteria in four multimedia constructed wetlands for rural wastewater treatment. The results indicated that the abundance of functional genes for nitrogen removal in the rhizosphere layer (0 to 30 cm), water distribution layer (30 to 50 cm), multime filler layer (50 to 130 cm), and catchment layer (130 to 170 cm) of the constructed wetlands were closely related. The rhizosphere layer was conducive to the absolute enrichment of dominant genes.

Towards multi-level biomonitoring of nematodes to assess risk of nitrogen and phosphorus pollution in Jinchuan Wetland of Northeast China.

Cultivation for agricultural production often poses threats to nearby wetlands ecosystems in fertile landscapes. In this study, nematode ecological indexes were assessed through the main soil properties of the wetlands, farmlands, and edges of wetlands and farmlands in Jinchuan Wetland by the random sampling. Behavior and reproduction in Caenorhabditis elegans (C.

Fate of free chlorine in drinking water during distribution in premise plumbing.

Free chlorine is a potent oxidizing agent and has been used extensively as a disinfectant in processes including water treatment. The presence of free chlorine residual is essential for the prevention of microbial regrowth in water distribution systems. However, excessive levels of free chlorine can cause adverse health effects.

Impact of precipitation patterns on biomass and species richness of annuals in a dry steppe.

Annuals are an important component part of plant communities in arid and semiarid grassland ecosystems. Although it is well known that precipitation has a significant impact on productivity and species richness of community or perennials, nevertheless, due to lack of measurements, especially long-term experiment data, there is little information on how quantity and patterns of precipitation affect similar attributes of annuals. This study addresses this knowledge gap by analyzing how quantity and temporal patterns of precipitation affect aboveground biomass, interannual variation aboveground biomass, relative aboveground biomass, and species richness of annuals using a 29-year dataset from a dry steppe site at the Inner Mongolia Grassland Ecosystem Research Station.