Respiration Values Research Articles

Implementation of Gyro Accelerometer Sensor for Measuring Respiration Rate Based on Inhale and Exhale Using Kalman Filter

Respiratory rate is a fundamental vital sign that is sensitive to different pathological conditions including heart, lung, emotional stress, the influence of body temperature and activity fatigue. The respiratory rate in humans is measured by counting the number of breaths for one minute by monitoring and counting the number of times the chest rises and falls during the inhale and exhale process. Various methods for measuring respiratory rate that are commonly used including pneumograph, impedance and capnography are applied in patient monitoring. This study aims to examine and analyze the application of the kalman filter on the output of the gyro accelerometer sensor to increase the results of the detection of respiratory rates using the gyro accelerometer sensor. This study test was carried out using a patient simulator in Surabaya Ministry of Health Polytechnic nursing laboratory. This simulator patient can simulate respiration with a mechanical work system up and down the chest and abdomen, uses an Arduino Nano microcontroller to filter the output of the gyro accelerometer sensor and the results will be compared before and after the filter. The independent variable in this study is the respiration value, while the dependent variable is the sensor output before being filtered. In the relaxed condition of the respondent The most effective use of the kalman filter is found in the parameters R = 10, Q = 0.1 because in the use of these parameters, the value after being filtered has a value that tends to be stable. The highest error value in the application of the gyro accelerometer sensor occurs at sensor position 1 with R = 1 Q = 10 value of 2,6%. This study shows the effect of differences in respiration values before and after using a kalman filter. This study has limited differences in values that are far between the pre filter and after being filtered in several data collections.

Biogeochemical appraisal of carbon fractions and carbon stock in riparian soils of the Ganga River basin

The farmers are approaching river/reservoir beds to produce crops and vegetables during the lean periods, especially post-monsoon, winter, and summer, for their livelihood in changing climatic scenarios. Comparing C fractions, C stocks, and microbial indices between the terrestrial (conventional agricultural land: CAL) and riparian zones (reservoir riparian zones: RSRZ and river riparian zones: RRZ) reveals that cultivating riparian zones is environmentally stressful and climatically vulnerable to livelihood practices. The moist riverbed conditions for cultivation result in the accumulation of residual biomass and the burial of soil organic matter. The C fractions showed decreasing trends as CAL > RSRZ > RRZ. The mean TOC stock was found high in the CAL soils (45.04 Mg C ha−1) than in the RRZ (40.65 Mg C ha−1) and RSRZ soils (38.01 Mg C ha−1). The labile C fraction (KMnO4-C) varied from 2.34 to 3.29 % of TOC, and the RSRZ and RRZ soils showed 14.50 % and 40.32 % less KMnO4-C than the CAL soils. The relationship between KMnO4-C and mineralizable C (Cmin) showed high potential for organic carbon stabilization in riparian soils. The microbial biomass carbon (MBC) and basal soil respiration (BSR) values were nearly half of the CAL in the RRZ soils indicating limited carbon substrate availability to the microbial decomposition. Low mineralization quotient (qM) and high metabolic quotient (qCO2) indicated stressful microbial utilization of labile TOC in the RRZ soils. The high carbon management index (CMI) showed the potential to store and sequester TOC in riparian soils. The artificial neural networks (ANN) were used to examine the impact of soil properties on the prediction efficiency of TOC stocks in the three farming zones.

Influence of earthworms on the microbial properties and extracellular enzyme activities during vermicomposting of raw and distilled grape marc

The treatment of winery wastes by using appropriate management technologies is of utmost need in order to reduce to a minimum their disposal and avoid negative environmental impacts. This is of particular interest for grape marc, the main solid by-product of the winery industry. However, comparative studies on a pilot-scale dealing with the impact of earthworms on marc derived from both red and white grape varieties during vermicomposting are still scarce. The present study sought to evaluate the changes in the biochemical and microbiological properties of red and white raw marc in the presence and the absence of the earthworm species Eisenia andrei. The distilled marc obtained through distillation of the red grape marc was also considered under this scenario. Samples were taken after 14, 28, 42, and 63 days of vermicomposting. On day 14 earthworms led to a pronounced increase in most of the enzymatic activities, but only in those vermireactors fed with raw marc from the red grape variety. Alfa- and beta-glucosidase as well as chitinase and leucine-aminopeptidase activities were between 3 to 5-times higher relative to the control, while alkaline phosphomonoesterase was even up to 14-fold higher with earthworm presence. From day 28 onwards the magnitude of earthworms' effect on the studied enzymes was also dependent on the type of grape marc. Reduced values of basal respiration, ranging between 200 and 350mg CO2 kg OM h-1 and indicative of stabilized materials were found in the resulting vermicomposts. Moreover, the content of macro- and micronutrients in the end products matched with those considered to have the quality criteria of a good vermicompost. Altogether, these findings reinforce the effectiveness of vermicomposting for the biological stabilization of grape marc with the dual purpose of fertilizer production and environmental protection.

СЕЗОННАЯ ИЗМЕНЧИВОСТЬ ПОТОКОВ ДИОКСИДА УГЛЕРОДА, ЯВНОГО И СКРЫТОГО ТЕПЛА В СЕВЕРОТАЕЖНОМ ЛИСТВЕННИЧНОМ ЛЕСУ СРЕДНЕЙ СИБИРИ ПО ДАННЫМ ПУЛЬСАЦИОННЫХ ИЗМЕРЕНИЙ

The seasonal and daily variability of sensible and latent heat and carbon dioxide (CO2) fluxes, as well as the sensitivity of the fluxes to changing environmental conditions were derived by the eddy covariance flux measurements in an undisturbed northern-taiga larch forest on continuous permafrost in Central Siberia from the end of May to the end of September in 2013 and 2015. The measurements showed a high seasonal and daily variability of CO2, sensible and latent heat fluxes. It was found that whereas dry and sunny weather conditions of June and July in 2013 and 2015 resulted in lower daily latent heat fluxes as compared to sensible ones, mostly cloudy and rainy weather in the second half of the summer led to the reduced net radiation and increased latent heat fluxes. The daily values of gross primary production from the beginning of June to mid-August in 2013 and 2015 exceeded the values of the ecosystem respiration, and the forest ecosystem was the sink of CO2 from the atmosphere. The maximum CO2 uptake was observed in late June and early July, primarily due to high photosynthesis rates influenced by high incoming solar radiation, optimal air temperature, and soil moisture conditions. Since mid-August, the balance between the CO2 uptake and release was close to zero. The total net ecosystem CO2 exchange during the growing season of 2013 was -76.5 g C/m2, while it was slightly higher (-103.6 g C/m2) during the growing season of 2015, primarily due to higher air temperatures in June and greater precipitation in the summer months of 2015.

Soil Biological Activity, Carbon and Nitrogen Dynamics in Modified Coffee Agroforestry Systems in Mexico

(1) Background: Coffee agroforestry systems (CAFS) in Veracruz, Mexico, are being displaced by avocado monocultures due to their high economic value. This change can generate alterations in the type of organic residues produced and soil biological activity (SBA) which is sensitive to climatic variations, changes in floristic composition, and agronomic management. It can be evaluated through soil respiration and macrofauna, both related to soil carbon (C) and nitrogen (N) dynamics. The objective was to: (1) Analyze the variation of SBA as well as the C and N dynamics in modified coffee agroforestry systems; (2) Methods: Three CAFS (renewed, intensive pruning, and with the introduction of avocados) and an avocado plantation were compared. The evaluations were conducted during the period 2017–2019. Soil parameters (respiration, macrofauna, C and N contents) and C content of plant biomass were measured in plots of 25 × 25 m2 from three soil depths in triplicate. Spearman’s test and a principal component analysis were performed to determine the structural dependence on C and N dynamics; (3) Results: The introduction of avocado showed the lowest soil respiration values (with 193 g CO2 ha−1 h−1 at 0–10 cm depth), this system did not display soil macrofauna and increased soil organic carbon content. The soil C/N ratio was sensitive to the introduction of avocado. Correlation between soil respiration and litter-related parameters was positive, but it was negatively correlated with soil organic matter and total soil nitrogen, explaining 67.7% of the variation; (4) Conclusions: Modification of CAFS generated variations in the SBA and soil C and N contents.

Impact of NPK fertilization on hazelnut yield and soil chemical-microbiological properties of Hazelnut Orchards in Western Georgia

In this study, the effects of ground and foliar applications of the NPK fertilizers in hazelnut orchards on the soil chemical and microbiological properties and hazelnut yield were investigated. The fertilization practicesses from ground were done two times using NPK (20:10:10 +trace elements) on March and May while the fertilization practices from leaf were done three times using NK (15:12 +trace elements) on May, June and July at six different hazelnut orchards located on Samegrelo, Guria and Adjara regions in Western Georgia in 2018. The alkaline characterized fertilizer applications from soil generally increased soil reaction (pH), nutrient contents and EC values in different magnitude depends on the soil characteristics of locations. The lowest soil pH (4,40) and EC (0,107 dS m-1) values showed the highest increment (10,7% and 77,6%, respectively) over the control. The basal soil respiration and Cmic values of all hazelnut orchards were generally increased by the NPK ferilization. Increasing soil pH and EC by the fertilization also increased CA and DHA activity. The mean values of percent increase in yield and yield parameters by the NPK fertilization were obtained as 8,3% in yield, 13,3% in shelled nut weight, 10,0% in kernel weight and 5,1% in percent kernel efficiency. The hazelnut yield value had significant positive correlation with soil pH (0,669*), EC (0,652*) and Cmic (0,620*) values. The foliar fertilization and improving the soil properties of hazelnut orchards by the application of alkaline characteristic NPK fertilizer from soil increased hazelnut yield and yield parameters compare with the farmer applications or control treatments. The increments in soil microbiological properties and nutrients are considered as a desirable result in terms of sustainable soil management and plant nutrition for hazelnut orchards.

​Clinical Study on Penicillin Anaphylaxis and Role of Oxidative Stress and Pro-inflammatory Markers: An Implication for Therapy

Background: Penicillin belongs to the β-Lactam group of antibiotics which is used as a first-line drug in veterinary medicine. The occurrence of penicillin anaphylaxis and its pathophysiology is rarely reported in ruminants. Methods: In the present study, oxidative stress and pro-inflammatory response were investigated in 4 cases (Jersey crossbred) of penicillin hypersensitivity by assessing oxidative stress biomarkers and pro-inflammatory cytokines. Animals in the current experimental plan were divided into three groups, group I included penicillin hypersensitive (n=4), group II included penicillin tolerant (n=6) and group III (n=10), included healthy control animals. Result: Mean values of temperature, heart rate and respiration were significantly (p less than 0.05) elevated in the penicillin-sensitive group compared to the penicillin tolerant and control group. The present study revealed significantly (p less than 0.05) elevated levels of lipid peroxidation (MDA), xanthine oxidase (XO), nitric oxide (NO), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), while as levels of glucose-6-phosphate dehydrogenase (G6PD), superoxide dismutase (SOD) and glutathione peroxidase (GPx) were significantly reduced in the penicillin-sensitive group. Levels of G6PD showed significant positive correlation with GPx (r=0.54, P less than 0.001) and catalase (r=0.34, P less than 0.05) while as significant negative correlation with XO (r=0.39, P less than 0.05) was observed. Collectively, these findings indicate that the pathophysiology of penicillin hypersensitivity involves anti-oxidant imbalance and enhanced pro-inflammatory response and targeting these pathways can have therapeutic implications for penicillin hypersensitivity.

CO2 exchange of the ecosystem–atmosphere in a mountain forest ecosystem: Combining stable carbon isotope (δ13C) and soil respiration measurements

Stable carbon isotopes (δ13C) are a useful technique to partition the net ecosystem–atmosphere exchange (NEE) of carbon dioxide (CO2) into gross primary productivity (GPP) and respiratory (R) components. The acquisition of ecosystem flux is usually performed using the eddy covariance (EC) technique, but this method is limited under complex terrain conditions and stable atmospheric conditions. Here, we try to develop the flux partitioning theory of mountain forest ecosystem by combining isotope technology and soil respiration. We used a full growing season of isotopic profile data and soil respiration data from a temperate deciduous forest on Jiufeng Mountain to demonstrate the method and quantify its uncertainties. We found that the assessable systematic uncertainty was ± 29.97% for NEE, ±24.87% for GPP, and ± 36.82% for R. The factors that most strongly affected the uncertainties of GPP and R were canopy CO2 stomatal conductance (gco2), calculated by the Köstner model, and the carbon isotope value of the total respiration in the ecosystem at night (δ13Cn-eco), calculated by the Keeling plot method. The advantage of isotopic methods is not only the relief of terrain restrictions but also the stable atmospheric conditions. The method provides an innovative vision for the partitioning of flux in forest ecosystems, especially for mountain forests.

Unjuk Kinerja Sistem Aerasi Dalam Kotak Penyimpanan Kentang (Solanum tuberrosum L) Tipe Kotak

The purpose of this study was to determine the performance of the box type potato storage aeration system in terms of changes in temperature and RH of the air during storage. Research on a box type aeration system for potato storage was carried out by measuring the temperature and RH of the incoming air, the temperature and the RH of the outgoing air during storage of potatoes for 21 days. In addition, calculating the heat of respiration, heat to increase the temperature of potatoes, heat to evaporate water and heat lost to the environment using a simple mathematical model approach. The results showed that the temperature and RH of the room and the incoming air flow tended to form a linear pattern, while the RH of the process room and the outgoing air flow tended to form a polynomial pattern. The temperature of the potato storage room was in the range of 24.07-25.70oC and the RH was in the range of 56.0-65.6%. The heat value of respiration varied between 261.42 - 311.88 k.Joule/kg potato tubers, because the storage temperature was 24.07-25.70oC. The heat generated by the respiration process used to evaporate water from the potato tubers to the environment is 6.01±0.3% on average, the average heat to raise the temperature of the potato tubers and the air temperature around the potato is 24.08±1, 3%, and the average heat loss to the environment with the flowing air is 59.89±3.4%.

The impact of newly synthesized sulfonamides on soil microbial population and respiration in rhizospheric soil of wheat (Triticum aestivum L.).

Antibiotics released into agricultural fields through the manure of grazing animals could exert harmful impacts on soil microbes and plants. Antibiotics exert high impacts on environment than other pharmaceuticals due to their higher biological activity. However, little is known about their impacts on plants, despite indications that antibiotics exert negative effects on soil microorganisms, which ultimately harm the plants. It has been demonstrated that beneficial microorganisms promote plant growth and development under various stresses. This study evaluated the toxicity of four newly derived sulfonamides (SAs), i.e., 2-(phenylsulfonyl) hydrazine carbothioamide (TSBS-1), N, 2-bis phenyl hydrazine carbothioamide (TSBS-2), aminocarbonyl benzene sulfonamide (UBS-1), and N, N’-carbonyl dibenzene sulfonamide (UBS-2) on bacterial growth and soil microbial respiration. Each SA was tested at four different concentrations (i.e., 2.25, 2.5, 3, 4 mg/ml) against five rhizospheric bacterial strains, including AC (Actinobacteria sp.), RS-3a (Bacillus sp.), RS-7a (Bacillus subtilis), RS-4a (Enterobacter sp.), and RS-5a (Enterobacter sp.). Antimicrobial activity was checked by disc diffusion method, which showed that inhibition zone increased with increasing concentration of SAs. The UBS-1 resulted in the highest inhibition zone (11.47 ± 0.90 mm) against RS-4a with the highest concentration (4 mg/ml). Except TSBS-1, all sulfonamide derivatives reduced CO2 respiration rates in soil. Soil respiration values significantly increased till 6th day; however, exposure of sulfonamide derivatives suppressed microbial respiration after 6th day. On the 20th day, poor respiration activity was noted at 0.23, 0.2, and 0.4 (CO2 mg/g dry soil) for TSBS-1, UBS-1, and UBS-2, respectively. Our results demonstrate that sulfonamides, even in small concentrations, significantly affect soil microbial population and respiration. Soil microbial respiration changes mediated by sulfonamides were dependent on length of exposure and concentration. It is recommended that antibiotics should be carefully watched and their impact on plant growth should be tested in the future studies.

Components of respiration and their temperature sensitivity in four reconstructed soils

Seasonal changes characteristics in the respiration of four reconstructed soil masses in a barren gravel land were monitored. The results showed that (1) Respiration and heterotrophic respiration of the four reconstructed soils with added meteorite, shale, sand increased gradually with increasing soil temperatures, reaching its maximum in summer and decreasing to its minimum in winter. the average annual respiration of reconstructed soil with sand was 4.87 μmol·m–2·s–1, which was significantly higher than the other reconstructed soils (p < 0.05). (2) The maximum and minimum values of autotrophic respiration for the four reconstructed soils appeared in August 2018 and January 2018, respectively. the proportion of autotrophic respiration to total respiration was 12.5–38.0%, 9.5–42.0%, 7.7–41.2%, and 5.0–39.3% for the soils with reconstituted meteorite, shale, sand, and soft rock, respectively. (3) The relationship between respiration and the temperature of reconstructed soils can be represented by an exponential function. The 90% to 93% changes in reconstructed soils respiration were caused by soil temperature. The temperature sensitivity (Q10) of reconstituted soil with added sand was significantly higher than that of the other three reconstituted soils.

Organic amendment regulates soil microbial biomass and activity in wheat-maize and wheat-soybean rotation systems

Long-term heavy application of inorganic fertilizers is associated with a decrease in soil quality and biodiversity. Organic amendments have been reported to positively affect soil quality; however, relatively little is known regarding soil carbon (C) cycle enzyme kinetic parameters (Vmax and Km), community-level physiological profiles (CLPP), and the interactions between these factors and soil microbes and physicochemical properties under sustained organic amendment. Therefore, this study aimed to evaluate the effect of organic amendments on crop yield, soil chemical properties, microbial activity, enzyme kinetic parameters of five extracellular C cycle-related hydrolase enzymes, and soil microbial functional diversity in wheat-maize (WM) and wheat-soybean (WS) rotation crop systems. The results of the study showed that combined application of organic and inorganic fertilizers increased crop yield (6.81–17.47%), soil total organic C (TOC, 29.44–39.54%), total nitrogen (TN, 24.22–50.79%), available potassium (AK, 39.47–59.62%), total dissolved nitrogen (TDN, 19.68–33.75%), dissolved organic C (DOC, 14.54–55.10%), available phosphorus (AP, 34.81–243.90%), and microbial biomass C and nitrogen (MBC, 17.65–40.86% and MBN, 18.63–50.76%) concentration. The combined application also enhanced microbial growth when compared with an inorganic amendments regime. Additionally, the combined application of organic and inorganic fertilizers increased soil microbial activity and catabolic diversity and maintained a high substrate-induced respiration (SIR) value. Furthermore, the conversion from a WM rotation to a WS rotation increased both soil pH and microbial biomass, and the resultant soil exhibited lower potential activity and higher enzyme-substrate affinity. Overall, the findings of this study showed that an increase in soil microbial biomass is a key determinant of microbial catabolic activity and functional diversity.

Manure Maturation with Biochar: Effects on Plant Biomass, Manure Quality and Soil Microbiological Characteristics

Application of biochar and composts prepared from organic wastes as soil amendments has been recognized as a beneficial strategy to enhance soil fertility and crop production. However, the modification of manures with applied organic amendments such as biochar has not been well explained. Therefore, the preliminary study was designed to evaluate the impact of two doses of biochar (low 0.4 kg + 10 kg of manure and high 4 kg + 10 kg of manure) on the modification of resulting co-composted manure properties, and subsequently to evaluate the effect of matured manure amendment on the soil chemical and biological properties and plant yield in the pot experiment with barley (Hordeum vulgare L.). The following variants were tested: control, manure (M), manure + low biochar dose (M + LB), manure + high biochar dose (M + HB). Results revealed that, the M + HB significantly improved the co-composted manure properties as compared to control and M + LB, respectively. The most pronounced effects of M + HB treatment were observed on pH, NH4-N and humic acid to fulvic acid ratio (used as an index for manure maturity) relative to other treatments. Similarly, significant variations were observed between AOB (ammonium oxidizing bacteria) and nirs genes under M + HB which lowered the AOB and increased the nirs abundance as compared to other treatments. Moreover, when applied to soil, M + HB increased the observed soil chemical parameters with the exception of TN contents as compared to M and M + LB treatments. Similarly, plant biomass was significantly enhanced under the applied M + HB treatment. However, statistically insignificant differences were observed regarding soil enzyme activities and soil respiration values under the applied amendments. Thus, it was concluded that the co-composted manure with high biochar dose can have the potential to enhance the manure properties, soil fertilization value and plant biomass. However, its effects on soil microbiological and enzyme activities were intended be explored under long-term field experiments.

Structure and function of soil microbial communities in fertile islands in austral drylands

AbstractFertile islands are an important determinant of ecosystem functioning in drylands. These resource‐rich patches are maintained by complex interactions among biotic and abiotic factors. Soil microorganisms are responsible for essential ecosystem processes and could affect the ability of fertile islands to capture and cycle nutrients, both directly and indirectly enhancing the fertile island effect. In this context, we aimed to evaluate the attributes of soil microbial communities (abundance and activity), elucidate key drivers of the fertile island effect and analyze relationships with a range of soil parameters (physicochemical). The soils under shrub canopies had higher values of microbial biomass carbon (MBC) and soil basal respiration (SBR) rates than soils from intercanopy spaces. However, no differences were observed in Soil Organic Carbon (SOC) or in fungal and bacterial abundances between the microhabitats. Soil nutrient stocks (NPK) and pH values had a positive correlation with MBC and SBR. Also, a positive correlation was observed for fungi abundance and the K content of the soil. We also observed a positive correlation between the bacterial abundance and soil N content. This study suggests thatM. tridenscan be considered a keystone species that generates fertility islands, critical for biodiversity and ecosystem functioning. The keystone role thatM. tridensplays in this system underscores the importance of improving our understanding of these interactions (plant–soil‐microorganisms), especially important as drylands expand and aridity increases due to climate change in the second half of this century.

川中丘陵区冬水田种植模式转旱作土壤呼吸组分特征及碳平衡

PDF HTML阅读 XML下载 导出引用 引用提醒 川中丘陵区冬水田种植模式转旱作土壤呼吸组分特征及碳平衡 DOI: 10.5846/stxb202105281410 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: “十三五”国家重点研发计划"粮食丰产科技创新"专项项目(2017YFD0301702) Carbon balance and characteristics of soil respiration components during the transition from paddy field to upland in the hilly region of central Sichuan 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:冬水田-水稻是川中丘陵区传统的稻田种植模式,冬水田种植模式转变是实现多熟种植及机械化的重要途径。为探究冬水田-水稻种植模式转旱作过程中作物季及休闲期土壤呼吸速率及其组分构成,试验设置冬水田-水稻转旱作(FTD)、冬水田-水稻(FR)和冬闲田-玉米(FM)3种不同种植模式,采用根排除法和静态明箱-气相色谱法原位取样测定作物季及季后休闲期土壤呼吸及其组分,并通过测算净生态系统生产力(NEP)进而判断冬水田-水稻转旱作过程的农田系统碳汇强度。结果表明:(1)FTD显著提高了土壤总呼吸速率及其自养和异养呼吸速率,从而提高了其累积排放量(P<0.05)。与FR相比,FTD的土壤总呼吸及其自养和异养呼吸的累积排放量分别提高了13.14倍、11.32倍和15.56倍(P<0.05);与FM相比,FTD的土壤总呼吸及其自养和异养呼吸的累积排放量分别提高了70.56%、40.83%和115.47%(P<0.05)。(2)与FR和FM相比,FTD均降低了土壤呼吸及其组分的温度敏感性(Q10),且土壤总呼吸的温度敏感性介于异养呼吸和自养呼吸之间。(3)FR,FM和FTD的净生态系统生产力(NEP)均为正值,其数值分别为7911.66 kg/hm2,5667.89 kg/hm2和1583.46 kg/hm2,均表现为大气CO2的碳汇,但与FR与FM相比,FTD显著降低了其净生态系统生产力,呈现出较弱的碳汇。 Abstract:Winter paddy field-rice is a traditional rice planting pattern in the hilly areas of central Sichuan Province. The transformation of winter paddy field-rice planting pattern is an important measure to promote multi-cropping and mechanized cropping production. To investigate the soil respiration rate and its composition during crop season and fallow period during the transition from winter paddy field-rice to upland cropping (FTD), three different cropping patterns were set up in this experiment, including paddy field-rice to upland cropping (FTD), paddy field-rice (FR), and fallow field-corn (FM). Root removal method and static chamber gas chromatography were used to determine soil respiration and its components in crop season and fallow period after crop was harvested. The intensity of farmland carbon sink of FTD was evaluated by calculating net ecosystem productivity (NEP). The results showed that: (1) the total soil respiration rate, autotrophic respiration rate and heterotrophic respiration rate significantly increased in FTD than FR and FM (P<0.05). Compared with FR, the cumulative emissions amount of total soil respiration, autotrophic and heterotrophic respiration increased by 13.14 times, 11.32 times, and 15.56 times, respectively (P<0.05); Compared with FM, the cumulative emissions amount of the total soil respiration, autotrophic and heterotrophic respiration increased by 70.56%, 40.83% and 115.47%, respectively (P<0.05). (2) The respiration temperature sensitivity (Q10) value of total soil respiration, autotrophic respiration and heterotrophic respiration decreased in FTD than FR and FM. Meanwhile Q10 value of total soil respiration was between heterotrophic respiration Q10 value and autotrophic respiration Q10 value. (3) The NEP of FR, FM and FTD were positive, and their values were 7911.66 kg/hm2, 5667.89 kg/hm2 and 1583.46 kg/hm2, respectively. The three plant patterns were all the carbon sink of atmospheric CO2. Whereas, because the NEP in FTD was significantly lower than FR and FM, it only showed a weak carbon sink in FTD than that in FR and FM. 参考文献 相似文献 引证文献

Wood Dust in Furniture Manufacturing: An Exposure Determinant Study in Ağrı City

Wood dust exposed during furniture manufacturing processes causes a variety of health problems. The aim of this study is to determine the respirable and inhalable dust exposure of the employees in small-scale furniture workshops located in Ağrı Organised Industrial Zone. For this purpose, the amount of dust exposure in the working environment was measured and the results were compared with the limit values in national and international legislation. Five furniture carpentry workshops in Ağrı Industrial Zone employing less than 10 workers constituted the universe of the study. A total of 22 people work in five workplaces. A total of 15 employees, 3 from each workshop, participated in the study. In this study, "MDHS 14/3: Gravimetric analysis and sampling method of respirable and inhalable dusts" was used for dust sampling. In the study, 30 respirable dust samples and 5 inhalable(total) dust samples were obtanied at 5 workplaces. Based on these measurement results, a daily TWA was calculated for each employee according to the TS EN 689 standard. The results were compared with the values in the national and international standards. It was concluded that the exposed values for dust concentration obtained from only one workplace were below the national and international limit values. It has been observed that a large part of both respirable and inhalable dust exposure values in workplaces exceeded the limit values. Practices and regulations such as tax reductions, incentives and projects that will contribute to the fight against dust in small-scale enterprises should be made.

Analysis of the energy balance and CO2 flow under the influence of the seasonality of climatic elements in a mangrove ecosystem in Eastern Amazon

An unprecedented study was carried out in a mangrove ecosystem in the northeastern coast of the Brazilian Amazon to understand the behavior of climatic elements in a year with the occurrence of El Niño (2015), associated with the seasonal function source/sink of CO2 by the ecosystem. Global radiation (Rg), net radiation (Rn), temperature, relative humidity, precipitation, horizontal wind speed and direction, as well as turbulent flows of sensible heat (H), latent heat (LE), and carbon (f_CO2) were recorded using eddy covariance, a system for studying turbulent flows of heat and gases in the atmosphere. We observed a drastic reduction in rainfall volumes, which accounts for 63.7% of the expected total according to the region’s climatology. Regarding f_ CO2, the highest values of photosynthesis, autotrophic, and heterotrophic respiration of the ecosystem occurred in the wet season due to precipitation, ideal photosynthetically active radiation, lower soil salinity, and higher NDVI of the ecosystem. In the 2nd semester of the year, we observed that the decrease in cloudiness, causing a higher radiation supply in the forest canopy, accompanied by a reduction in precipitation and an increase in the value of H and soil salinity, favored the increase of foliar abscission by the dominant genus Rhizophora and Avicennia, thus influencing the reduction of magnitudes of carbon source/sink functions in the ecosystem during this season, even on high tide days.

Biocrust contribution to soil CO2 flux in desert shrubland ecosystem of northwest Mexico

Soil respiration is a critical ecological process and is a hierarchical component of ecosystem respiration that regulates the global carbon cycle. But there is scarce knowledge on respiration dynamics in water-stressed ecosystems and the influence of biocrusts. Soil respiration-values varied from 0.099 to 0.828 µmol s−1 m−2 after extraordinary rains; after this period, recorded values were null or negative at the most (0.000 to −0.055 µmol s−1 m−2). Shrubland soil with and without biocrusts showed the highest net CO2 exchange values and in disturbed soil with and without biocrusts (0.067; 0.059; 0.048, and 0.023 µmol s−1 m−2). The results showed that shrubland soil with BSC absorbed more CO2 than the rest of the experimental variants. Accordingly, the observed low precipitation combined with high temperatures and evapotranspiration could not activate the BSC respiration process. Such an event seemed to occur under specific temperature and moisture conditions, anyhow related to extraordinary rain events to emit CO2 to the atmosphere. Reports of negative soil respiration values in drylands are very scarce, so we discuss the possible processes that could cause this phenomenon for our study area.

Carbon and nitrogen stocks and microbial indicators in tropical semiarid degraded Luvisols

Overexploitation of natural forest resources under the environmental conditions on the tropical semiarid region of Brazil is the main cause of soil degradation. This leads to insufficient restoration of both microbial and plant biomass and net loss of C and N from soils. In this study, we investigated degraded, partially degraded, and preserved Luvisols to quantify functional and total microorganisms and their activities and determine total C and N stocks. We hypothesize that degraded Luvisols have significant reduction in C and N stocks, abundance, and activity of total bacteria and fungi, diazotroph and phosphorus-mineralizing bacteria in relation to preserved or partially degraded Luvisols. We evaluated total C and N contents and stocks, microbial biomass (C, N and P), soil basal respiration, alkaline phosphatase activity, glomalin content, metabolic and microbial quotients and quantified 16S rRNA, 18S rRNA, nifH and phoD genes by real time quantitative PCR. C and N stocks of degraded Luvisols were a third of the stocks found in preserved soils. The values of soil microbial biomass and soil basal respiration on the degraded soils were ca. 1/5 and 1/20 in preserved soils; however, there was no indication of metabolic stress. The abundance of diazotrophic and phosphorus-mineralizing bacteria decreased in degraded Luvisols; nevertheless, total bacteria and fungi gene abundance as well as the glomalin content remained unchanged. The alkaline phosphatase activity indicated that mineralizing microorganisms could make phosphorus constantly available even in soils without vegetation cover.

Effects of waterlogging and salinity increase on CO2 efflux in soil from coastal marshes

Coastal marshes play a notable role in sequestering carbon in plants and soil; however, coastal ecosystems are vulnerable to global change in terms of sea-level rise and saltwater intrusion. The effects of independent and interactive hydrological treatments of waterlogging and elevated salinity on soil CO2 effluxes in Spartina alterniflora marshes were investigated based on a mesocosm approach. This study highlighted the importance of respective soil respirations during inundation (nondrainage, Rs.ND) and reaeration (drainage, Rs.D) in the marshes soils. We found that waterlogging treatments heavily suppressed Rs.ND but increased the Rs.D, regardless of salinity levels. Light salinity enhanced soil respiration, whereas high salinity inhibited soil CO2 efflux, regardless of the water table level. Waterlogging strengthened the negative effects of salinity on Rs.ND and offset the negative effects on Rs.D. The variations in soil respiration under the hydrological treatments can be mainly attributed to changes in root biomass; indigenous soil microbial biomass; and activities of sucrase, cellulase and dehydrogenase, as well as ionic concentrations and oxidation-reduction potential. The temperature sensitivity (Q10 value) of soil respiration (only for Rs.D) after drainage showed a notable decline under the conditions of waterlogging and high salinity. The effect degree of coupled hydrological treatments on soil respiration and Q10 values was similar to a single waterlogging factor before drainage and more strongly than a single factor after drainage. We suggest that the soil CO2 efflux under water flooding and reaeration, inundation duration, and salinity levels need to be considered to understand the impacts of future hydrological changes on coastal marshes.