Temporal variation of dry weight, organic matter, chlorophyll α + phaeopigments and organic carbon of the periphyton on leaves of Typha dominguensis

1996 ◽  
Vol 81 ◽  
pp. 85-98
Author(s):  
Valéria de O. Fernandes ◽  
Francisco de A. Esteves
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Temporal Variation ◽  
Dry Weight

scholarly journals Organic matter mineralisation in contrasting agricultural soils amended with sewage sludge .

2014 ◽  
Vol 4 ◽  
Author(s):  
Jose Navarro Pedreño ◽  
Ignacio Gómez Lucas ◽  
Jose Martín Soriano Disla
Keyword(s):  
Organic Matter ◽  
Single Dose ◽  
Sewage Sludge ◽  
Organic Carbon ◽  
Soil Organic Carbon ◽  
Agricultural Soils ◽  
Dry Weight ◽  
Soil C ◽  
Multiple Sensor ◽  
Sludge Application

The mineralisation of organic matter (OM) when sewage sludge was used as amendment in 70 contrasting agricultural soils from Spain was analysed. Soils received a single dose of sewage sludge (equivalent to 50t dry weight ha<sup>-1</sup>) and the O<sub>2</sub> consumption was continuously monitored for 30 days using a multiple sensor respirometer in a laboratory experiment. The cumulative O<sub>2</sub> consumption and rates after 8 and 30 days of incubation (O<sub>2 cum</sub> 8d, 30d and O<sub>2 rate</sub> 8d, 30d), the respiratory quotient (RQ), the maximum O<sub>2</sub> rates over the incubation period (O<sub>2 max</sub>) and time from the beginning of the incubation when O<sub>2 max</sub> occurred (T<sub>max</sub>), were determined in both amended and non-amended soils. Sewage sludge application resulted in increased values for O<sub>2 max</sub>, O<sub>2 rate</sub> 8d, and O<sub>2 cum</sub> 30d. Differences were minor for T<sub>max</sub>, RQ 8d and O<sub>2 rate</sub> 30d. A considerable amount of the initial OM applied was mineralised during the first 8 days. Organic matter decomposition (as expressed by O<sub>2 cum</sub> 30d) was favoured in soils with high values of pH, carbonates, soil organic carbon and low values of amorphous Mn. Soils with these characteristics may potentially lose soil C after sewage sludge application.

Characteristics of Sediment and Organic Carbon Export from Pristine Boreal Forest Watersheds

1982 ◽  
Vol 39 (12) ◽  
pp. 1699-1718 ◽  
Author(s):  
Robert J. Naiman
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Boreal Forest ◽  
Particulate Organic Matter ◽  
Terrestrial Ecosystems ◽  
Dry Weight ◽  
Carbon Export ◽  
Watershed Area ◽  
First Choice ◽  
Spring Freshet

Estimates of the amount of material moving annually from terrestrial ecosystems to the ocean are largely based on an incomplete understanding of events occurring throughout the hydrologic year, and only a vague comprehension of in-stream processes controlling that export. Discharge, suspended sediment, particulate organic matter (POM; > 0.5 μm), dissolved organic carbon (DOC; <0.5 μm diameter), and the percentage of organic matter were measured from 1979 to 1981 in five pristine Quebec streams: First Choice Creek (1st order; watershed area: 0.25 km2), Beaver Creek (2nd order; 1.83 km2), Muskrat River (5th order; 204 km2), Matamek River (6th order; 673 km2), and the Moisie River (9th order; 19 871 km2). All streams, with the exception of First Choice Creek, have a strong spring freshet when 43–55% of the annual discharge occurs. By describing sediment and organic carbon export throughout the annual hydrologic cycle, 1 showed that during the 2-mo spring freshet 71–92% of the annual sediment load is exported but only 59–65% of the annual POM load, and only 47–51% of the annual DOC load. Sediment yield is relatively constant between watersheds (1.5–7.6 g∙m−2∙yr−1), as is POM export (1.0–6.7 g ash-free dry-weight [AFDW]∙m−2∙yr−1); however, export DOC varies from 3.1 g C∙m−2∙yr−1 in First Choice Creek to 48.4 g C∙m−2∙yr−1 in Beaver Creek. There appears to be rapid loading of carbon between 1st- and 2nd-order streams in boreal forests, followed by biological and physical processing as watershed area increases. Thus, for the Moisie River watershed, export of total organic carbon (TOC) is reduced to only 4.7 g C∙m−2∙yr−1. Export of coarse particulate organic matter (> 1 mm) is negligible (normally < 0.1 mg∙L−1), as is oxidation of the suspended load (< 0.5%∙d−1). Effects of summer storms, natural diel variations, and depth of sample from the water column are shown to have a minimal influence on concentrations. Rating curves (kg∙d−1 vs. discharge) are developed to estimate the annual yield of sediment, POM, and DOC, and to evaluate long-term variations. From the results I suggest that in-stream processing and retention devices exert considerable control over the quantity and nature of suspended organic material. Physical processes such as the discharge regime and stream power are relatively less important in determining organic concentrations, but more important in determining sediment concentrations.Key words: seston, carbon, sediment, boreal forest, watershed, river, stream, export

scholarly journals Content and changes in dissolved organic matter in meadow and arable soils over time

2019 ◽  
Vol 52 (2) ◽  
pp. 183
Author(s):  
Bożena Dębska
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Dissolved Organic Matter ◽  
Dissolved Organic Carbon ◽  
Seasonal Changes ◽  
Dry Weight ◽  
Arable Soils ◽  
Successive Sampling ◽  
Climate Conditions ◽  
Weight Content

<p>Considering the discrepancies in the reports on seasonal changes in the content of  dissolved organic carbon, this paper concerns the research which aimed at defining the content and seasonal changes in dissolved organic matter (DOM) in arable and meadow soils in moderate climate conditions. The research has involved the soils sampled in the kujawsko-pomorskie province (Poland). Gleic Phaeozems (meadow soils), Brunic Arenosols and Eutric Cambisols were sampled from the depth of 0-30 cm, 30-60 cm and 60-100 cm, November 2011 through September 2013. The soil samples were analyzed for dry weight content, pH, content of total organic carbon and total nitrogen. DOM was extracted with 0.004 mol·dm<sup>-3</sup> CaCl<sub>2</sub>, in the extracts the content of dissolved organic carbon (DOC) and dissolved nitrogen (DNt) were assayed. The share of DOC was determined by the soil management. The analysis of variance did not show significant differences in the content of TOC and Nt across the soil sampling dates. Were recorded changes in DOC and DNt between successive sampling dates; for topsoil for DOC – from -12.06% to 13.34% (meadow soils) and for DNt  -40.84% to 47.44% (arable soils).</p><p><strong> </strong></p>

scholarly journals LAJU DEKOMPOSISI BAHAN ORGANIK DAN PRODUKSI INVERTEBRATA AIR DI SUAKA PERIKANAN TELUK RASAU, SUMATERA SELATAN

2017 ◽  
Vol 3 (2) ◽  
pp. 71
Author(s):  
Husnah Husnah ◽  
Dessy Arisna
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Water Depth ◽  
Decomposition Rate ◽  
Dry Weight ◽  
Litter Bags ◽  
Litter Bag ◽  
Water Sampler ◽  
Leaf Bags ◽  
Physical And Chemical

Pembukaan lahan di lahan banjiran untuk berbagai kepentingan, mempengaruhi morfologi, siklus hidrologi, dan karakteristik fisika kimia air seperti input dan dekomposisi bahan organik yang akhirnya akan mempengaruhi struktur organisme invertebrata air dan produksi ikan di rawa banjiran. Penelitian ini bersifat percobaan lapangan yang bertujuan untuk mengetahui laju dekomposisi bahan organik dan produksi invertebrata air dilakukan di tiga stasiun di Teluk Rasau, Sumatera Selatan pada bulan September sampai Nopember 2009. Laju dekomposisi bahan organik dan produksi invertebrata air dilakukan dengan metode jaring kantong (litter bag) berukuran 20x10 cm dengan ukuran mata jaring2 mm. Daun dari tumbuhan yang dominan yaitu pohon serpang (Caesalpina sappan) yang hampir gugur dikumpulkan dan ditimbang bobot keringnya, dan 5 g dari daun tersebut dimasukan ke dalam jaring kantong. Pada masing-masing (stasiun) percobaan diletakan 40 kantong jaring dengan posisi20 kantong diletakan pada kedalaman air 0 m (perbatasan air dan darat) dan 20 kantong pada kedalaman 75 cm. Kantong diikatkan tiang kayu dan ditenggelamkan dengan menggunakanpemberat. Pengukuran jumlah bahan organik yang terdekomposisi dan produksi makrozoobenthos dilakukan pada minggu ke-2, 4, 6, 8, dan 10, dengan cara mengangkat empat kantong plastik pada masing-masing kedalaman. Contoh air diambil pada kedalaman 1 m dari dasar perairan denganmenggunakan kemmerer water sampler. Sebagian contoh dianalisis di lapangan (kedalaman air, kecerahan, suhu, pH, dan oksigen terlarut) dan sebagian lagi akan dianalisis di laboratorium (dissolved organic carbon, nitrogen total, dan fosfor total. Persentase serasah daun serpang yang terdekomposisiselama 10 minggu pada kisaran 40-55%. Koefisien laju dekomposisi serasah daun serpang pada muara Teluk Rasau yang berhubungan dengan Sungai Lempuing pada kedalaman 0 cm (k=0,1586) lebih rendah dari stasiun lainnya baik pada kedalaman 0 cm ataupun 75 cm (k=0,2076-0,2566). Produksi makrozobenthos di muara Teluk Rasau yang berhubungan dengan Sungai Lempuing baik pada kedalaman 0 cm ataupun 75 cm (9,25; 117,25 mg bobot kering/m2) secara nyata lebih rendah dari stasiun lainnya (17,75-22,08 mg bobot kering/m2; 260-807 mg bobot kering/m2). Kedalaman air, suhu, alkalinitas total, dan unsur hara sangat mempengaruhi laju dekomposisi serasah dan produksi makrozoobenthos. Clearance of floodplain area for multiple purposes influence morphology, hidrological cycle, and physical and chemical characteristics of water such as input and decomposition of organic matter in the waters. It finally affect the structure community of invertebrate and fish production. Experimental study in order to know decomposition rate of organic matter and aquatic invertebrate production was conducted at three sampling sites located in Teluk Rasau Fisheries Reserve Area of South Sumatera province from September to November 2009. Decomposition rate and invertebrate production was run with litter bag method. Leaf bags were constructed by placing 5 g of Caesalpina sappan in plastic with the size of 20x10 cm and mesh bags (mesh size 2 mm). Leaves were collected before abscission, air dried and stored. In each sampling sites, 20 litter bags were filled with dry leaves and placed on the sediment at water depth 0 m (transition between land and water), and another 20 litter bags were placed on the sediment at 0.75 m water depth. The litter bags were tied to the wood stake and anchored to the bottom. The leaf bags were tied together with a weighted rope and attached to a tree. Four replicate samples were removed after 2 days, to measure the leaching process, and then after 4, 6, 8, and 10 weeks for organic matter decomposition rate and invertebrate production measurement.The bags were cut from the rope and immediately placed in sealed plastic bags and returned to the laboratory. In the laboratory, the leaves were rinsed and separated from the invertebrate. The leaves were sorted by genus, dried at 50°C and weighed. invertebrate were counted and identified to different taxonomic levels. Physical and chemical water quality parameters were measured both in and exsitu by collecting water samples with kemmmerer water sampler at 1 m depth above the bottom. Parameters measured insitu were the water depth, transparency, temperature, pH value, dissolved oxygen, while, dissolved organic carbon, total nitrogen, and total phosphorus were analyzed in the laboratory. Results indicated that decomposition rate of Caesalpina sappan leaves for 10 weeks was in the range of 40-55%. The decomposition rate coefficient in the inlet of Teluk Rasau connevting to Lempuing River at depth 0 cm ((k=0.1586) was less than that in other sampling sites both at depth ocm and 75 cm (k=0.2076-0.2566). Macrozoobenthos production in the inlet of Teluk Rasau connecting to Lempuing River at depth 0 and 75 cm (9.25; 117.25 mg dry weight/m2) were less than that in other sampling sites (17.75-22.08 mg dry weight/m2; 260-807 mg dry weight/m2). Decomposition rate and invertebrate production of Caesalpina sappan were affected by water depth, temperature, total alkalinity, and nutrient.

Earth’s Middle Ages: What Came after the GOE

2017 ◽  
Author(s):  
Donald Eugene Canfield
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Middle Ages ◽  
Atmospheric Oxygen ◽  
Iron Formation ◽  
Banded Iron Formation ◽  
Dissolved Iron ◽  
Great Oxidation Event ◽  
Low Levels ◽  
Substantial Rise

This chapter considers the aftermath of the great oxidation event (GOE). It suggests that there was a substantial rise in oxygen defining the GOE, which may, in turn have led to the Lomagundi isotope excursion, which was associated with high rates of organic matter burial and perhaps even higher concentrations of oxygen. This excursion was soon followed by a crash in oxygen to very low levels and a return to banded iron formation deposition. When the massive amounts of organic carbon buried during the excursion were brought into the weathering environment, they would have represented a huge oxygen sink, drawing down levels of atmospheric oxygen. There appeared to be a veritable seesaw in oxygen concentrations, apparently triggered initially by the GOE. The GOE did not produce enough oxygen to oxygenate the oceans. Dissolved iron was removed from the oceans not by reaction with oxygen but rather by reaction with sulfide. Thus, the deep oceans remained anoxic and became rich in sulfide, instead of becoming well oxygenated.

scholarly journals Impact of aquaculture on distribution of dissolved organic matter in coastal Jeju Island, Korea, based on absorption and fluorescence spectroscopy

2021 ◽  
Author(s):  
Jeonghyun Kim ◽  
Yeseul Kim ◽  
Sung Eun Park ◽  
Tae-Hoon Kim ◽  
Bong-Guk Kim ◽  
...  
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Fluorescence Spectroscopy ◽  
Dissolved Organic Matter ◽  
Coastal Water ◽  
Coastal Region ◽  
Principal Component ◽  
Distribution Patterns ◽  
Organic Pollution ◽  
Jeju Island

AbstractIn Jeju Island, multiple land-based aquafarms were fully operational along most coastal region. However, the effect of effluent on distribution and behaviours of dissolved organic matter (DOM) in the coastal water are still unknown. To decipher characteristics of organic pollution, we compared physicochemical parameters with spectral optical properties near the coastal aquafarms in Jeju Island. Absorption spectra were measured to calculate the absorption coefficient, spectral slope coefficient, and specific UV absorbance. Fluorescent DOM was analysed using fluorescence spectroscopy coupled with parallel factor analysis. Dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) were measured using high-temperature catalytic oxidation. The DOC concentration near the discharge outlet was twice higher than that in natural groundwater, and the TDN concentration exponentially increased close to the outlet. These distribution patterns indicate that aquafarms are a significant source of DOM. Herein, principal component analysis was applied to categorise the DOM origins. There were two distinct groups, namely, aquaculture activity for TDN with humic-like and high molecular weights DOM (PC1: 48.1%) and natural biological activity in the coastal water for DOC enrichment and protein-like DOM (PC2: 18.8%). We conclude that the aquafarms significantly discharge organic nitrogen pollutants and provoke in situ production of organic carbon. Furthermore, these findings indicate the potential of optical techniques for the efficient monitoring of anthropogenic organic pollutants from aquafarms worldwide.

scholarly journals Traces of sunlight in the organic matter biogeochemistry of two shallow subarctic lakes

2021 ◽  
Author(s):  
Marttiina V. Rantala ◽  
Carsten Meyer-Jacob ◽  
E. Henriikka Kivilä ◽  
Tomi P. Luoto ◽  
Antti. E. K. Ojala ◽  
...  
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Lake Sediments ◽  
Lake Water ◽  
Human Impacts ◽  
Global Environmental Change ◽  
Carbon Export ◽  
Subarctic Lakes ◽  
Carbon Regulation ◽  
In Situ Experiments

AbstractGlobal environmental change alters the production, terrestrial export, and photodegradation of organic carbon in northern lakes. Sedimentary biogeochemical records can provide a unique means to understand the nature of these changes over long time scales, where observational data fall short. We deployed in situ experiments on two shallow subarctic lakes with contrasting light regimes; a clear tundra lake and a dark woodland lake, to first investigate the photochemical transformation of carbon and nitrogen elemental (C/N ratio) and isotope (δ13C, δ15N) composition in lake water particulate organic matter (POM) for downcore inferences. We then explored elemental, isotopic, and spectral (inferred lake water total organic carbon [TOC] and sediment chlorophyll a [CHLa]) fingerprints in the lake sediments to trace changes in aquatic production, terrestrial inputs and photodegradation before and after profound human impacts on the global carbon cycle prompted by industrialization. POM pool in both lakes displayed tentative evidence of UV photoreactivity, reflected as increasing δ13C and decreasing C/N values. Through time, the tundra lake sediments traced subtle shifts in primary production, while the woodland lake carried signals of changing terrestrial contributions, indicating shifts in terrestrial carbon export but possibly also photodegradation rates. Under global human impact, both lakes irrespective of their distinct carbon regimes displayed evidence of increased productivity but no conspicuous signs of increased terrestrial influence. Overall, sediment biogeochemistry can integrate a wealth of information on carbon regulation in northern lakes, while our results also point to the importance of considering the entire spectrum of photobiogeochemical fingerprints in sedimentary studies.

Soil organic matter formation is controlled by the chemistry and bioavailability of organic carbon inputs across different land uses

2021 ◽  
Vol 770 ◽  
pp. 145307
Author(s):  
Mohammad Bahadori ◽  
Chengrong Chen ◽  
Stephen Lewis ◽  
Sue Boyd ◽  
Mehran Rezaei Rashti ◽  
...  
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Organic Carbon ◽  
Land Uses ◽  
Soil Organic Matter Formation

Removal of trihalomethanes from high organic matter water sources using aeration: a feasibility study

2020 ◽  
Vol 55 (2) ◽  
pp. 184-197
Author(s):  
Saeideh Mirzaei ◽  
Beata Gorczyca
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Feasibility Study ◽  
Distribution Systems ◽  
Water Age ◽  
Treated Water ◽  
Canadian Guideline ◽  
Viable Solution ◽  
By Products

Abstract In this study, diffused aeration was applied to remove trihalomethane (THM) compounds from chlorinated, treated water containing high dissolved organic carbon (DOC) of 6.8 ± 1.2 mg/L. Increasing air-to-water volumetric ratio (rA/W) from 16 to 39 enhanced total THM (TTHM) removal from 60 to 70% at 20 °C and from 30 to 50% at 4 °C. Although bromodichloromethane has lower Henry's law constant than chloroform (CF), it was removed by a higher degree than CF in some aeration trials. Albeit obtaining high removals in aeration, TTHM reformed, and their concentration surpassed the Canadian guideline of 100 ppb in about 24 hours at 20 °C and 40 hours at 10 °C in all attempted air-to-water ratios. The water age in the system investigated in this study varied from 48 hours in midpoint chlorine boosting stations to 336 hours in the nearest endpoint. This study showed that THM removal by aeration is not a viable solution to control the concentration of these disinfection by-products in high-DOC treated water and in distribution systems where water age exceeds 24 hours; unless, it is going to be installed at the distribution endpoints.

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