Reed Wetland Research Articles

Effects of substrate improvement on winter nitrogen removal in riparian reed (Phragmites australis) wetlands: rhizospheric crosstalk between plants and microbes.

With continued anthropogenic inputs of nitrogen (N) into the environment, non-point source N pollutants produced in winter cannot be ignored. As the water-soil interface zones, riparian wetlands play important roles in intercepting and buffering N pollutants. However, winter has the antagonistic effect on the N removal. Substrate improvement has been suggested as a strategy to optimize wetland performance and there remain many uncertainties about the inner mechanism. This study explores the effects of substrate improvement on N removal in winter and rhizospheric crosstalk between reed (Phragmites australis) and microbes in subtropical riparian reed wetlands. The rates of wetland N removal in winter, root metabolite profiles, and rhizosphere soil microbial community compositions were determined following the addition of different substrates (gravel, gravel + biochar, ceramsite + biochar, and modified ceramsite + biochar) to natural riparian soil. The results showed that the addition of different substrates to initial soil enhanced N removal from the microcosms in winter. Gravel addition increased NH4+-N removal by 8.3% (P < 0.05). Gravel + biochar addition increased both TN and NH4+-N removals by 8.9% (P < 0.05). The root metabolite characteristics and microbial community compositions showed some variations under different substrate additions compared to the initial soil. The three treatments involving biochar addition decreased lipid metabolites and enhanced the contents and variety of carbon sources in rhizosphere soil, while modified ceramsite + biochar addition treatment had a greater impact on the microbial community structure. There was evidence for a complex crosstalk between plants and microbes in the rhizosphere, and some rhizosphere metabolites were seen to be significantly correlated with the bacterial composition of the rhizospheric microbial community. These results highlighted the importance of rhizospheric crosstalk in regulating winter N removal in riparian reed wetland, provided a scientific reference for the protection and restoration of riparian reed areas and the prevention and control of non-point source pollution.

An dataset of carbon and water fluxes over the reed wetlands in Panjin City (2018–2020)

With significant carbon sink capacity, active water vapor exchange and heat regulation capacity, wetlands are key ecosystems for stabilizing greenhouse gas emissions and mitigating climate change. Despite Liaohe Delta wetland being the largest warm temperate coastal wetland in Asia, its long-term carbon and water fluxes of the wetland are still not thoroughly examined, which limits the accuracy of simulating CO2 fluxes and regional carbon sinks. As a result, it is urgent to carry out long-term data monitoring and sorting in this area. This dataset is the flux data of the reed wetland ecosystem in Liaohe Delta from 2018 to 2020, collected from the Panjin Reed Wetland Research Station of the Northeast Ecological and Agrometeorological Field Experimental Base of China Meteorological Administration. Based on the data processing system of China Flux Observation and Research Network (ChinaFLUX), we established the standardized dataset of ecosystem carbon and key meteorological elements, including data files at half-hourly, daily, monthly and yearly scales. This dataset is of great significance in accurately evaluating the status and roles of carbon and water fluxes in the reed wetland ecosystem of Liaohe Delta in the regional and global carbon and water cycles.

Net ecosystem productivity of Panjin Phragmites australis wetland during 1971 to 2020 and its impact factors.

Coastal estuarine wetland ecosystem has strong ability for carbon (C) storage and sequestration. Accurate assessment of C sequestration and its environmental impact factors is the basis of scientific protection and mana-gement of coastal estuarine wetlands. Taking the Panjin reed (Phragmites australis) wetland as the object, we used terrestrial ecosystem model, together with Mann-Kendall mutation test, statistical analysis methods, and scenario simulation experiment, to analyze the temporal characteristics, stability, changing trend of net ecosystem production (NEP) of wetlands and the contribution rate of environmental impact factors to NEP during 1971 to 2020. The results showed that the annual average NEP of Panjin reed wetland was 415.51 g C·m-2·a-1 during 1971 to 2020, with a steady increase rate of 1.7 g C·m-2·a-1, which would still have a continuous increasing trend in the future. The annual average NEP in spring, summer, autumn, and winter was 33.95, 418.05, -18.71, and -17.78 g C·m-2·a-1, with an increase rate of 0.35, 1.26, 0.14 and -0.06 g C·m-2·a-1, respectively. In the future, NEP would show an increasing trend in both spring and summer, but a declining trend in both autumn and winter. The contribution rates of environmental impact factors to NEP of Panjin reed wetland depended on temporal scale. At the interannual scale, the contribution rate of precipitation was the highest (37.1%), followed by CO2 (28.4%), air temperature (25.1%) and photosynthetically active radiation (9.4%). Precipitation mainly affected NEP in both spring and autumn with the contribution rates of 49.5% and 38.8%, while CO2 concentration (36.9%) and air temperature (-86.7%) were dominant in summer and winter, respectively.

Rhizospheric Microbiota and Metabolite Interactions Affect the Aboveground Carbon and Soil Carbon of Lakeshore Reed (Phragmites Australis) Wetlands in a Subtropical Region

Rhizospheric Microbiota and Metabolite Interactions Affect the Aboveground Carbon and Soil Carbon of Lakeshore Reed (Phragmites Australis) Wetlands in a Subtropical Region

Effect of land use and cover change on soil organic carbon fractions and enzymatic activities in lakeshore wetland of north shore of Lake Chaohu

为了揭示湖滨带土地利用与覆被改变对土壤有机碳库及生态功能的影响，本文选取了巢湖湖滨带（北岸）9个典型样方，分析和比较了表层（0~30 cm）土壤有机碳组分特征以及相关酶的活性.结果表明，巢湖湖滨带不同采样点土壤总有机碳（TOC）含量变化范围为2.88~11.2 g/kg，平均含量为9.12 g/kg，其中原生芦苇（Phragmites australis）湿地土壤TOC含量最高（11.2 g/kg），而芦苇群落消失后形成的荒滩土壤TOC含量最低，仅为2.88 g/kg.表征湖滨带湿地缓冲性能的土壤阳离子交换量（CEC）也以原生芦苇湿地土壤为最高，并与TOC含量呈现明显正相关.湖滨带表层土壤溶解性有机碳（DOC）和易氧化有机碳（EOC）含量变化范围分别为150~370 mg/kg和1.7~5.2 g/kg，其变化幅度明显高于TOC，其中DOC含量各采样点差异最为显著.除多酚氧化酶外，次生水柳林（Homonoia riparia Lour.）表层土壤几种酶的活性较原生芦苇湿地土壤皆有所上升，特别是蔗糖酶活性增加幅度最为明显.受人类活动干扰较大的湖滨绿地公园和人工草滩土壤过氧化氢酶、脲酶和蔗糖酶酶活性普遍显著低于原生芦苇湿地.除多酚氧化酶外，土壤中几种酶活性与土壤有机碳组分EOC和DOC含量均呈现显著的正相关，其中蔗糖酶活性与DOC含量之间相关系数最高（r=0.907），其相关性均达到极显著水平.土壤溶解性有机碳和蔗糖酶可以作为表征因土地利用与覆被变化导致湖滨带湿地退化以及生态恢复效果的敏感性指标.;In order to explore the effect of land use and cover change on lakeshore soil organic carbon sequestration and it ecological function, nine typical sample plots with different plantations along the north shore of Lake Chaohu were investigated, and the surface soils (0-30 cm) organic carbon fractions and the enzymes activities were analyzed and compared. The results showed that soil total organic carbon (TOC) was 2.88-11.2 g/kg, with an average of 9.12 g/kg. The soil under native Phragmites australis reed wetland showed the highest TOC content, and the TOC content in the wasteland formed after the disappearance of P. australis reed community was the lowest with the value of only 2.88 g/kg. The cation exchange capacity (CEC), which can be used to characterize the buffer performance of lakeside zone, was highest in the native P.australis reed wetland soil and positively correlated with TOC. Soil labile organic carbon fractions content, including dissolved organic carbon (DOC) and easily oxidized organic carbon (EOC) from the lakeshore wetland, ranged from 150 to 370 mg/kg and from 1.7 to 5.2 g/kg, respectively. The range of change in soil DOC and EOC between different sampling sites was larger than that in TOC. Especially, the difference of DOC content between different vegetations was the most significant. The activities of several determined enzymes in the surface soil of secondary Homonoia riparia Lour. Forest, except polyphenol oxidase, were higher than those in native P. australis reed wetland soil. Especially, the invertase activity increased most obviously. However, lakeshore urban green park and artificial grassland showed significantly lower activities of catalase, urease and invertaseas compared with native P. australis wetland. Correlation analysis showed that there existed significant relationships between soil enzyme activities except polyphenol oxidase and soil DOC and EOC. Especially, the correlations of invertase activity to the content of DOC reached remarkably significant level with the highest coefficient (r=0.907). Based on the above results, it is concluded that the DOC and invertase as the sensitive indicators, could well characterize the degradation process and ecological restoration effect on lakeshore wetland buffering function due to land use and cover change.

Exploring the Habitat Restoration and Landscape Construction of the Wetland Lakeside Zone in the Lujiang Section on the Southern Bank of the Chaohu Lake

This article proposes the corresponding situation from the four aspects of the wetland along the south bank of the Chaohu Lake, the aquatic reed wetland habitat, the aquatic plant landscape, the anti-wave forest and the slope protection, combined with the current situation and treatment of the lakeside line in the Lujiang section on the south bank of Chaohu Lake. Focusing on the habitat and landscape construction of the south bank of the Chaohu Lake wetland, it emphasizes the principle of ecological priority, highlights the application of ecological engineering technology, continues the urban“blue vein green network” ecological pattern, which strengthens the construction of ecological corridors and protection systems, and that establishes a stable and excellent ring. Chaohu wetland lakeside ecosystem.

Exogenous nitrogen addition inhibits sulfate-mediated anaerobic oxidation of methane in estuarine coastal sediments

Anaerobic oxidation of methane (AOM) plays an important role in regulating methane (CH4) emissions from coastal wetland ecosystems. In recent decades, coastal estuarine wetlands have been subjected to great environmental pressure associated with terrestrial nitrogen (N) input. Here, we used 13CH4 to quantify AOM rates in coastal wetland sediments with and without vegetation in the Yangtze River Estuary in East China. Impact of addition of inorganic N forms (NO3−, NO2− and NH4+) on AOM process was assessed by 13CH4 anaerobic oxidation into 13C-CO2 and 13C-SOC, as well as by community structure and quantitative characteristics of anaerobic methanotrophic (ANME) archaea. The results showed that AOM process occurred in the bare wetland (BW) and reed wetland (RW). Inorganic N addition, regardless of N forms, notably decreased AOM rates by 14–58% in the BW sediments and by 26–65% in the RW sediments. Rates of 13CH4 assimilation into SOC, which were similar to but faster than rates of AOM into CO2, were reduced by 12%–66% under inorganic N addition. After 120-day anaerobic incubation, the net changes in the relative abundance of ANME-2 and ANME-3 were significantly correlated with AOM rates in the RW and BW, respectively, thereby indicating their contribution to the variation in AOM under N addition. Our findings provide insight into the potential consequences of terrestrial N input; these may weaken CH4 consumption by anaerobic oxidation in the Yangtze River Estuary, and decrease carbon stabilization and storage in coastal wetland sediments.

Surface Energy Flux Changes and Budget in a Typical Coastal Reed Wetland (Liaohe Delta, China)

Jia, Q.; Zhou, L.; Yu, W.; Wang, X.; Wen, R., and Xie, Y., 2020. Surface energy flux changes and budget in a typical coastal reed wetland (Liaohe Delta, China). Journal of Coastal Research, 36(5), 1005–1012. Coconut Creek (Florida), ISSN 0749-0208.Coastal wetlands are located between the continents and oceans, and their surface energy flux changes and budget play an important role in regulating regional climate. Liaohe Delta is a typical coastal reed wetland in China. The latent heat, sensible heat, and net radiation flux of reed wetlands in Liaohe Delta were studied for four consecutive years (2012–2015) on the basis of the eddy correlation system. The average annual accumulation of latent heat flux was 1525.39 MJ m–2, with a large seasonal variation. The latent heat flux was positive, and the peak value did not exceed 320 W m–2 in the daytime. The latent heat flux increased with the increase of temperature each day. The annual average sensible heat flux was 550.96 MJ m–2, with the minimum sensible heat in June and July, and the daily average change peak did not exceed 160 W m–2. The annual net radiation accumulation was 2868.32 MJ m–2, and the net radiation in winter decreased. The maximum value of net radiation in summer reached 622 W m–2. Latent heat flux accounted for 41%–63% of solar radiation, followed by storage flux, and sensible heat flux had the lowest value. This typical reed wetland has a strong water vapor regulation ability. These results contribute to research on land surface processes in wetlands.

Phosphorus Storage Capacity and Loss Risk in Coastal Reed Wetland Surrounding Bohai Sea

Coastal wetland, at the intersection of land and sea, is considered as a "sink", "source", and "transformer" of phosphorus (P). Coastal wetland plays an important role in the global P cycle, and its ability to retain excessive P in water receives increasing attention. In this study, the coastal reed wetland sediments surrounding the Bohai Sea were sampled to investigate P adsorption capacity and loss risk by conducting batch experiments. Results show that the maximum P adsorption capacity (Qmax) was 693.7-2117.2 mg·kg-1, with an average of 1468.6 mg·kg-1. The Qmax decreased in the order of Qilihai Wetland > Beidagang Wetland > Nandagang Wetland > Liaohe Delta Wetland > Shouguang Coastal Wetland > Yellow River Delta Wetland. The P adsorption capacity was related to the contents of Ca, Mg, and TOC. The degree of P adsorption saturation (DPS) and loss risk index (ERI) of the coastal wetland were 0.28%-4.50% and 0.53%-10.10%, respectively. The ERI suggested that the P loss risk was relatively low for coastal reed wetland surrounding the Bohai Sea except for the moderate loss risk for Shouguang coastal wetland. In summary, the reed coastal wetland around Bohai Sea demonstrated significantly P storage capacity and served as a P sink for water P. We recommend to fully utilize the coastal wetland to reduce point or non-point source pollution (e.g., P) during the remediation or recovery of the polluted Bohai Sea.

黄河三角洲芦苇湿地底栖无脊椎动物与环境因子的关系研究——以石油开采区与淡水补给区为例

PDF HTML阅读 XML下载 导出引用 引用提醒 黄河三角洲芦苇湿地底栖无脊椎动物与环境因子的关系研究——以石油开采区与淡水补给区为例 DOI: 10.5846/stxb201901100087 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家重点研发计划项目（2017YFC0505901）；国家青年科学基金项目（41801084）；吉林省科技发展计划项目（20180101080JC）；中国博士后科学基金项目（194419） Composition of benthic invertebrate communities in reed (Phragmites australis) wetlands of the Yellow River Delta: Comparisons between oil exploitation and freshwater recharge areas Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:分别于2018年5月和8月对黄河三角洲芦苇湿地19（淡水补给区11处，石油开采区8处）处采样点的底栖无脊椎动物和水体理化指标进行调查采样，运用统计方法分析两个区域物种组成、优势种、多样性、群落结构以及与环境因子的关系。结果表明：两季共采集到底栖无脊椎动物54种，主要以水生昆虫、腹足纲和软甲纲为主，淡水补给区和石油开采区各类群组成差异明显。独立样本T检验表明淡水补给区和石油开采区水体理化指标间差异显著（P<0.05）。双因子方差分析显示，昆虫纲和腹足纲密度在两区域差异显著（P<0.05），软甲纲和腹足纲密度在季节上差异明显（P<0.05）。底栖无脊椎动物优势种共10种，淡水补给区指示物种8种，而石油开采区未发现有指示物种。聚类和非参数多维排序（nMDS）显示，底栖无脊椎动物群落结构相似性较低；RDA结果表明：淡水补给区底栖无脊椎动物群落结构主要受Cond，TDS，Sal，pH，Eh，HCO3-，SO42-等环境因子的影响。石油开采区底栖无脊椎动物群落结构影响较大的环境因子为HCO3-、NH4-N。 Abstract:The benthic invertebrates and environmental factors were sampled and analyzed in May and August, 2018 from 19 sites of reed wetlands (11 freshwater recharge areas and 8 oil exploitation areas) in the Yellow River Delta. Multivariate analysis methods were used to analyze the composition, dominant species, biodiversity, community of benthic invertebrate assemblages, as well as their relationships to the environmental factors. The results showed that 54 taxa collected by two samplings were mainly composed by Aquatic Insect, Gastropoda and Mollusca. There are obvious differences in composition of benthic invertebrates between freshwater recharge and oil exploitation area. Independent-Samples T Test showed that freshwater recharge area and oil exploitation area were significant different in environmental factors (P<0.05). Two-way ANOVA analysis showed that there were significant differences in insect and Gastropoda density between the two regions (P<0.05). The seasonal variations of Mollusca density and Gastropoda density were both significant (P<0.05). Ten species of benthic invertebrates were dominant in the study area. Eight species of benthic invertebrate were tested to be the indicator species in freshwater recharge area, but no indicator species were found in oil exploitation area. Cluster and nMDS analysis indicated the low similarity of the benthic invertebrate community between the freshwater recharge area and oil exploitation area. The RDA results showed that the community structure of benthic invertebrates in freshwater recharge area was mainly affected by Cond, TDS, Sal, pH, Eh, HCO3-, SO42- and the influential environmental factor in oil exploitation areas were HCO3-and NH4-N. 参考文献 相似文献 引证文献

Transition Period Between Vegetation Growth and Senescence Controlling Interannual Variability of C Fluxes in a Mediterranean Reed Wetland

Key Points Interannual variability of C fluxes of the Mediterranean wetland mainly depends on the behavior of reed dynamics during the transition to senescence period Evapotranspiration of the Mediterranean reed wetland does not present a relevant interannual variability The role of the Mediterranean reed wetland in the global warming is determined far more by the CO2 than the CH4

Activity Factors and Differences in Activity by Period of Red-eared Slider Turtles (&lt;i&gt;Trachemys scripta elegans&lt;/i&gt;) in Ansan Reed Wetland

Activity Factors and Differences in Activity by Period of Red-eared Slider Turtles (&lt;i&gt;Trachemys scripta elegans&lt;/i&gt;) in Ansan Reed Wetland

Effects of five years’ nitrogen deposition on soil properties and plant growth in a salinized reed wetland of the Yellow River Delta

Atmospheric nitrogen (N) deposition caused by human activities has been shown to have significant impacts on ecosystem structure and function, but the reported impacts have been inconsistent among studies. To test the effects of N deposition on a salinized reed wetland, we built a long-term nitrogen deposition experimental platform in the Yellow River Delta (YRD), China. The present study investigated soil chemical properties, soil enzyme activities and plant growth parameters after five years of N deposition. Results showed that the concentration of NH4-N and NO3-N increased significantly with the increasing level of nitrogen addition, but no significant influences were observed in total nitrogen (TN), total organic carbon (TOC) and available phosphorous (AP) across N addition treatments. Higher amounts of N addition significantly increased the urease activity (Ure) and alkaline phosphatase activity (Alp), but did not enhance the activity of invertase (Inv). The activities of Ure and Alp were positively correlated with the concentration of soil NO3-N, TN and TC, respectively, but negatively correlated to soil salt content. Meanwhile, the plant height and productivity were significantly stimulated, and the surface soil salt content decreased significantly. The results suggest that atmospheric N deposition may help improve the function of salinized reed wetland ecosystems in the YRD by increasing soil nutrient content, stimulating soil enzyme activity and enhancing plant production.

Expert-Based Evaluation of Ecosystem Service Provision in Coastal Reed Wetlands Under Different Management Regimes

A characteristic feature of lagoons and estuaries along the Baltic Sea is the dominance of reed (Phragmites australis) along their coasts. Reed wetlands are ecologically valuable ecosystems, play an important role for nutrient and matter cycling as well as for biodiversity. They provide a broad spectrum of ecosystem services and are utilized by humans already for centuries. We assess the ecosystem service provision of reed wetlands, analyze how this is affected by different management scenarios and how the results of an expert based ecosystem service assessment can be used in practice. Because of strong internal gradients and interactions with the surrounding, coastal reed belts show a higher ecosystem service provision compared to homogeneous inland reed. The three different coastal management scenarios are 1) winter harvest of reed, 2) summer harvest of reed and 3) grazing by livestock. According to the views of 18 involved experts from Lithuania, Poland and Germany, winter harvest is regarded as the scenario with the lowest conflict potential between nature protection and reed utilization. Experts expect no changes or even slight increases for regulating and cultural services. However, experts see the need to establish a sustainable and regionally anchored winter harvest concept. Summer harvest and grazing entail the risk to change the ecosystem structure and could lead to a shift in vegetation pattern towards short saltmarsh grassland. Experts expect a slight decrease in regulating services. Especially erosion control, biodiversity or nutrient sequestration are rated controversially. To our experience, these expert-based ecosystem service assessments can support policy implementation (e.g. NATURA 2000, European Water Framework Directive or Marine Strategy Framework Directive). It can serve as a tool that allows stakeholders to visualize trade-offs, analyze patterns and processes at regional scales and hence facilitate decision-making.

Antagonistic effect of nitrogen additions and warming on litter decomposition in the coastal wetland of the Yellow River Delta, China

Human activities have changed global nitrogen (N) cycling in the last decades. Global warming has potential to alter the decomposition of organic carbon. At the moment the effects of inorganic and organic N additions on litter decomposition, alone and in combination with increasing temperature, are not well known. A filed experiment of N addition (nitrate, ammonium and organic N) was conducted in the reed (Phragmites australis) wetlands in the Yellow River Delta, China. At the end of second growing season, the standing litter (leaf and stem) of reed were collected, and were incubated (90 days) to determine the combined effects of N forms and increasing temperature on litter decomposition. The CO2 production was defined as litter decomposition. The results showed that increasing temperature accelerated stem litter decomposition, and had no effect on leaf litter decomposition. Nitrogen additions inhibited leaf and stem litter decomposition due to the decrease in C/N ratio. Ammonium and organic N additions had larger inhibitory effects on stem litter decomposition compared with nitrate addition. This highlights the importance of differentiating the effects of N forms on litter decomposition. Moreover, the combined effect of N additions and increasing temperature on both litter decomposition was antagonistic due to the decreased Q10 value of litter decomposition after N additions. Our results suggest that the negative effect of N addition on litter decomposition may be enhanced by increasing temperature in the near future.

How water transfer could promote the carbon sink in reed wetland

The hydrologic condition is the basic attribute of the wetland ecosystem, which affects the carbon exchange process between the wetland soil and the vegetation atmosphere, and then affects the change of carbon sink. Artificial water transfer or ecological replenishment is one of the most direct and effective measures used to control wetland saturation levels. The relationship was established, between water flux, water level fluctuation and the influence of artificial water transfer, to discuss the variation of carbon sink and when to implement water transfer and how to control water (water level) to achieve carbon sink in Baiyangdian reed (Phragmites australis) wetland under the influence of artificial water transfer. The research results show the amount of carbon sink is changed only-0.72 gC/m2 (-0.08%) in spring, and the influence is minimal, which is changed -19.49 kgC/m2 (-2.10%) in summer, and the adverse effect was great, which is changed 133.85 kgC/m2 (14.41%) in autumn, but the carbon sink increases and decreases, and the carbon sequestration is unstable, which is changed 17.89 kgC/m2 (1.93%) in winter, and the effect is favorable. Therefore, according to the effect of carbon sink in reed wetland, the time in the early spring of winter (February to March) is the best water transfer time in Baiyangdian. When the water level fluctuation is controlled at 0.3 m, the carbon sink change is 230.79 kgC/m2 (9.07%), which is beneficial to the increase of carbon sink in reed wetland. The model established in this study can be helpful to understand the mechanism of carbon sink in reed wetland through artificial water transfer in Reed wetlands, also can be used in the optimal design of the ecological service function for the restoration of damaged wetland.

A Study on the Changes in NDVI of Panjin Reed Wetland and an Analysis on Its Correlation with Meteorological Factors

As the main body of the Liaohe River Delta, the Panjin Wetland plays a vital role in maintaining the ecological balance throughout the region. The analysis of the correlation between NDVI and meteorological factors was carried out on reed wetland by using the normalized differential vegetation index (NDVI) data of Panjin Reed Wetland from 2006 to 2015 and such meteorological data as ten-day average temperature, ten-day precipitation, ten-day sunshine duration, ten-day relative humidity and ten-day evaporation capacity. The results showed that the NDVI of Panjin Reed Wetland had no obvious year-to-year changes from 2006 to 2015 and showed a slight upward trend with small fluctuations. However, the NDVI of Panjin Reed Wetland had significant intra-annual changes and was depicted as a single-peaked curve in the crop growing season. The curve reached the peak value in early- and mid-July, which was highly consistent with the phenophase. The ten-day NDVI of reed wetland is most and positively correlated to the ten-day average temperature, with the correlation coefficient reaching a value of 0.7874.

博斯腾湖人工和天然芦苇湿地土壤CO2、CH4和N2O排放通量

PDF HTML阅读 XML下载 导出引用 引用提醒 博斯腾湖人工和天然芦苇湿地土壤CO2、CH4和N2O排放通量 DOI: 10.5846/stxb201610302213 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 新疆维吾尔自治区重点实验室专项基金项目（XJDX0909-2014-05）；新疆师范大学硕士研究生科技创新项目（XSY201602002） Emission fluxes of CO2, CH4, and N2O from artificial and natural reed wetlands in Bosten Lake, China Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:为研究干旱区淡水湖泊人工、天然芦苇湿地土壤温室气体源汇强度及其影响因素，采用静态箱-气相色谱法，于2015年1月-12月对博斯腾湖人工和天然芦苇湿地土壤CO2、CH4和N2O通量进行全年观测。结果表明，人工芦苇湿地土壤CO2、CH4和N2O排放通量变化范围分别为：10.1-588.4mg m-2 h-1、2.9-82.4μg m-2 h-1和1.32-29.7μg m-2 h-1，天然芦苇湿地土壤CO2、CH4和N2O排放通量变化范围分别为10.3-469.6mg m-2 h-1、3.1-64.8μg m-2 h-1和1.9-14.3μg m-2 h-1。人工和天然芦苇湿地夏季土壤CO2排放通量均明显高于其他季节，而土壤CH4和N2O排放通量较大值多集中在春末夏初。全年观测期间，人工芦苇湿地土壤CO2、CH4和N2O排放通量高于天然芦苇湿地（P>0.05）；温度是影响人工、天然芦苇湿地土壤CO2和N2O排放通量的关键因素，近地面温度和5cm土壤温度与CO2和N2O排放通量呈现极显著的正相关关系（P<0.01）。土壤CH4排放通量是温度和水分二者共同影响的，由近地表温度、5cm土壤温度和土壤含水量共同拟合的方程可以分别解释人工、天然芦苇湿地土壤CH4排放通量的71%、74.5%；土壤有机碳、pH、盐分、NH4+-N、NO3--N也是人工、天然芦苇湿地土壤CO2、CH4和N2O排放通量的影响因素；人工和天然芦苇湿地土壤均是CO2、CH4和N2O的"源"。基于100年尺度，由3种温室气体计算全球增温潜势得出，人工芦苇湿地全球增温潜势大于天然芦苇湿地（15150.18kg/hm2 > 12484.21kg/hm2）。 Abstract:CO2, CH4, and N2O, have strong warming potentials and are considered to be the primary greenhouse gases in the atmosphere. Global warming caused by the increasing concentrations of atmospheric CO2, CH4, and N2O is one of the hotspots in global change field. Greenhouse gas (GHG) fluxes in reed wetlands are critical in evaluating the source/sink strength of GHG in arid area. We studied the dynamics of soil CO2, CH4, and N2O fluxes using static chamber-based on gas chromatography in two reed wetlands of the freshwater Bosten Lake, located in an arid area of Northwestern China. During a full year of monitoring, environmental variables (including soil moisture, soil temperature, air temperature, pH and salinity) were measured to determine the effects of abiotic factors on soil CO2, CH4, and N2O fluxes in artificial and natural reed wetlands. SPSS 19.0 for Windows was used to analyze the relationships between environmental factors and soil CO2, CH4, and N2O fluxes. The results showed that soil CO2, CH4, and N2O fluxes in the artificial reed wetland were 10.1-588.4mg m-2 h-1, 1.32-29.7μg m-2 h-1 and 3.1-64.8μg m-2 h-1, respectively, which was comparable with the values from the natural reed wetland. Higher soil CO2 emissions occurred in summer, whereas CH4 and N2O emissions mainly occurred in late spring and early summer. Temperature was the main factor controlling soil CO2 and N2O fluxes in both reed wetlands (P < 0.01). Soil CH4 emission flux was affected by both temperature and moisture. According to regression analysis, the combination of near-surface temperature, top 5cm soil temperature, and soil water content could explain 71% and 74.5% of soil CH4 flux in artificial and natural reed wetlands, respectively. Soil organic carbon, pH, salinity, NH4+-N, and NO3--N are also influencing factors of CO2, CH4, and N2O fluxes in artificial and natural reed wetlands. However, the differences in CO2, CH4, and N2O emissions from soils of artificial and natural reed wetlands were caused by differences in soil organic carbon, soluble nitrogen, and biomass. Based on the centennial scale, the soils of artificial and natural reed wetland were "sources" of GHG, and the global warming potential from artificial reed wetland was higher than that from natural reed wetland. 参考文献 相似文献 引证文献

The Levels and Potential Carcinogenic Risks of PAHs in Liaohe Estuarine Reed Wetland Soils.

Sixteen polycyclic aromatic hydrocarbons (PAHs) were quantified by GC/MS in 30 soil samples of Liaohe estuarine reed wetland. The total concentrations of 16 PAHs ranged from 235 to 374ngg-1, and seven carcinogenic PAHs concentrations were in the range of 83-109ngg-1. A probabilistic carcinogenic potential for three age groups (including children, teenagers, and adults) exposed to soil PAHs via three pathways was quantitatively calculated based on Monte Carlo simulations. The 95th percentiles carcinogenic risks of PAHs for children, teenagers, and adults were 7.80×10-8, 4.03×10-8, and 1.14×10-7, respectively. The carcinogenic risk levels were all below 10-6, indicating no potential for cancer development. Dermal contact and accident ingestion of soil were the dominant exposure pathways to soil PAHs. BaP and DBahA were the major contributors to carcinogenic risk in this study.Sensitivity analysis demonstrated that exposure duration and PAH concentrations in soil were the key exposure parameters in calculating carcinogenic risk. Results from this study will provide valuable information for potential scientific evaluation and prevention for carcinogenic risk exposed to soil PAHs.

Methane production potential and emission at different water levels in the restored reed wetland of Hangzhou Bay.

Changes in the hydrological conditions of coastal wetlands may potentially affect the role of wetlands in the methane (CH4) cycle. In this study, the CH4 production potential and emissions from restored coastal reed wetlands at different water levels were examined in eastern China at a field scale in two phenological seasons. Results showed that the total CH4 flux from reeds at various water levels were positive, indicating that they were “sources” of CH4. During the peak growing season, CH4 flux from reeds was greater than that during the spring thaw. CH4 flux from reeds in inundated conditions was greater than that in non-inundated conditions. The CH4 production potential during the peak growing season was far greater than that during the spring thaw. However, the effect of water level on wetland CH4 production potential differed among seasons. The correlations among CH4 production potential, soil properties and CH4 flux change at different water level. These results demonstrate that water level was related to CH4 production and CH4 flux. The growing season also plays a role in CH4 fluxes. Controlling the hydrological environment in restored wetlands has important implications for the maintenance of their function as carbon sinks.