scholarly journals Carbon Dioxide Fluxes and Carbon Stocks under Conservation Agricultural Practices in South Africa

Agriculture ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 374 ◽  
Author(s):  
Patrick Nyambo ◽  
Chiduza Cornelius ◽  
Tesfay Araya
Keyword(s):  
South Africa ◽  
Carbon Dioxide ◽  
Soil Moisture ◽  
Carbon Stock ◽  
Crop Residue ◽  
Agricultural Practices ◽  
Carbon Stocks ◽  
Residue Management ◽  
Co2 Fluxes ◽  
Carbon Dioxide Fluxes

Understanding the impacts of agricultural practices on carbon stocks and CO2 emission is imperative in order to recommend low emission strategies. The objective of this study was to investigate the effects of tillage, crop rotation, and residue management on soil CO2 fluxes, carbon stock, soil temperature, and moisture in the semi-arid conditions in the Eastern Cape of South Africa. The field trial was laid out as a split-split-plot design replicated three times. The main plots were tillage viz conventional tillage (CT) and no-till (NT). The sub-plots were allocated to crop rotations viz maize–fallow–maize (MFM), maize–oat–maize (MOM), and maize–vetch–maize (MVM). Crop residue management was in the sub-sub plots, viz retention (R+), removal (R−), and biochar (B). There were no significant interactions (p > 0.05) with respect to the cumulative CO2 fluxes, soil moisture, and soil temperature. Crop residue retention significantly increased the soil moisture content relative to residue removal, but was not different to biochar application. Soil tilling increased the CO2 fluxes by approximately 26.3% relative to the NT. The carbon dioxide fluxes were significantly lower in R− (2.04 µmoL m−2 s−1) relative to the R+ (2.32 µmoL m−2 s−1) and B treatments (2.36 µmoL m−2 s−1). The carbon dioxide fluxes were higher in the summer (October–February) months compared to the winter period (May–July), irrespective of treatment factors. No tillage had a significantly higher carbon stock at the 0-5 cm depth relative to CT. Amending the soils with biochar resulted in significantly lower total carbon stock relative to both R+ and R−. The results of the study show that NT can potentially reduce CO2 fluxes. In the short term, amending soils with biochar did not reduce the CO2 fluxes compared to R+, however the soil moisture increases were comparable.

STUDI FLUKS KARBON DIOKSIDA PADA BERBAGAI TIPE PENGGUNAAN DI LAHAN GAMBUT PASANG SURUT DAN PEDALAMAN (Study of Carbon dioxide Fluxes (CO2 fluxes) on Various Land Use in Low Tide and Ombrotrophic Peatland)

AgriPeat ◽  
2019 ◽  
Vol 18 (02) ◽  
pp. 68-81
Author(s):  
Journal Journal
Keyword(s):  
Carbon Dioxide ◽  
Soil Moisture ◽  
Soil Temperature ◽  
Rubber Plantation ◽  
Co2 Fluxes ◽  
Forest Land ◽  
Carbon Dioxide Fluxes ◽  
Ombrotrophic Peatland ◽  
A Value ◽  
Burnt Areas

ABSTRACT The aim of this study to known Co2 fluxes in low tide and ombrotrophic peatland on forest land, ex- burns land, rubber tree land, and maize land and to known amount of microbial populations there. Observation method was carried out at the village Kalampangan (ombrotrophic peatland) , Sebangau, Palangka Raya, and at the village Purwodadi (low tide peatland), Maliku, Pulang Pisau, from May to July 2014. Observation variables consist of CO2 fluxes, fluctuations of groundwater levels, soil temperature, soil humidity and microbial populations. The results show that overall carbon dioxide fluxes higher in low tide peatland, with the highest fluxes in burnt areas, 430.24 mg C m-2 h-1, whereas in Ombrotrophic peatland, the highest on 292 forested land, 92 mg C m-2h-1. In Ombrotrophic peatland, relation between fluxes of carbon dioxide and the soil temperature is significant in the burnt areas with a value of R = 0.856 with a quadratic pattern, with the average temperature of 28.89 ° C. Fluxes of carbon dioxide significantly effected by soil moisture that is at a rubber plantation with a value of R = 0.640 with quadraticpatterned, average soil moisture of 0.61 m3/m-3. Fluxes of carbon dioxide to the groundwater depth is significant on a rubber plantation with a value of R = 0.872 with a quadratic pattern, and depth of groundwater on average of 83.74 cm. The populatuin of microorganisms, in forest land 137 sel/ml, rubber plantations 154 sel/ml, cornfields 157 sel/ml and ex-burnt is 80 sel/ml. In Low Tide peatland, fluxes of carbon dioxide to the soil temperature is significant in forest land with the value of R = 0.545 with cubic pattern, and the average temperature of 27,39 oC. Soil moisture has the siginificant effect to fluxes of carbon dioxide that is in the burnt areas with a value of R = 0.617 with patterned quadratic, and average soil moisture of 0.50 m3/m-3. The ground water depth has a siginificant effect to fluxes of carbon dioxide in a cornfield with a value of R = 0.743 with a quadratic pattern, and the depth of soil water on average of 68.98 cm. Population of soil microorganisms, in forest land 73 sel/ml, rubber plantations 36 sel/ml, cornfields 51 sel/ml and ex-burnt 18 sel/ml. Soil temperature, soil moisture, groundwater depth and microoganisms effect on carbon dioxide fluxes. Key words : carbondioxide, fluxes, microorganisms, peatland ABSTRAK Tujuan Penelitian adalah untuk mengetahui pengaruh tipe penggunaan lahan gambut pasang surut dan lahan gambut pedalaman, baik pada hutan alami, eks kebakaran, lahan pertanian (jagung) dan perkebunan karet terhadap fluks karbon dioksida dan mengetahui pengaruh jumlah mikroorganisme terhadap fluks karbon dioksida pada hutan alami, eks kebakaran, lahan pertanian (jagung) dan perkebunan karet pada kedua tipe lahan gambut tersebut. Penelitian dilaksanakan dari tanggal 23 Mei sampai dengan 19 Juli 2014 (2 bulan) di Kalampangan dan Purwodadi (Kanamit). Hasil Penelitian menunjukkan, fluks karbon dioksida secara keseluruhan lebih tinggi di Gambut Pasang Surut dibandingkan dengan di Pedalaman. Rata-rata fluks karbon dioksida di Gambut Pasang Surut, Jurnal AGRI PEAT, Vol. 18 No. 2 , September 2017 : 68 - 81 ISSN :1411 - 6782 69 pada lahan berhutan 285, 22 mg C m-2h-1, pada kebun karet 264,69 mg C m-2h-1, pada kebun jagung 232,08 mg C m-2h-1, pada lahan bekas kebakaran 430,24 mg C m-2h-1. Meskipun demikian, di Gambut Pedalaman, pada lahan berhutan lebih tinggi dibanding di Pasang Surut yaitu 292, 92 mg C m-2h-1, pada kebun karet 224,93 mg C m-2h-1, pada kebun jagung 211,30 mg C m-2h-1, pada lahan bekas kebakaran 228,07 mg C m-2h-1. Di Gambut Pedalaman, hubungan fluks karbon dioksida terhadap suhu tanah yang berpengaruh nyata yaitu pada areal bekas kebakaran dengan nilai R = 0,856 dengan berpola kuadratik, suhu rata-rata 28,89 oC. Fluks karbon dioksida terhadap kelembaban tanah yang berpengaruh nyata yaitu pada kebun karet dengan nilai R = 0,640 dengan berpola kuadratik, kelembaban tanah rata-rata 0,61 m3/m-3. Hubunganfluks karbon dioksida terhadap kedalaman air tanah yang berpengaruh nyata yaitu pada kebun karet dengan nilai R = 0,872 berpola kuadratik dengan kedalaman air tanah rata-rata 83,74 cm. Mikroorganisme, di lahan hutan 137 sel/ml, kebun karet 154 sel/ml, kebun jagung 157 sel/ml dan dilahan bekas kebakaran 80 sel/ml. Di Gambut Pasang Surut, hubungan fluks karbon dioksida terhadap suhu tanah yang berpengaruh nyata yaitu pada lahan hutan dengan nilai R = 0,545 dengan berpola kubik, suhu rata- rata 27,39 oC. Hubungan fluks karbon dioksida terhadap kelembaban tanah yang berpengaruh nyata yaitu pada lahan bekas kebakaran dengan nilai R = 0,617 dengan berpola kuadratik, kelembaban tanah rata-rata 0,50 m3/m-3. Hubungan fluks karbon dioksida terhadap kedalaman air tanah yang berpengaruh nyata yaitu pada kebun jagung dengan nilai R = 0,743 berpola kuadratik dengan kedalaman air tanah rata-rata 68,98 cm. Mikroorganisme, di lahan hutan 73 sel/ml, kebun karet 36 sel/ml, kebun jagung 51 sel/ml dan dilahan bekas kebakaran 18 sel/ml. Suhu tanah, kelembaban tanah, kedalaman air tanah berpengaruh terhadap fluks karbon dioksida dan mikroorganisme pengaruhnya kecil. Kata kunci : carbondioxide, fluxes, microorganisms, peatland

scholarly journals Environmental influences on carbon dioxide fluxes over three grassland ecosystems in China

2009 ◽  
Vol 6 (12) ◽  
pp. 2879-2893 ◽  
Author(s):  
Y. Fu ◽  
Z. Zheng ◽  
G. Yu ◽  
Z. Hu ◽  
X. Sun ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Soil Moisture ◽  
Alpine Meadow ◽  
Growing Season ◽  
Co2 Fluxes ◽  
Meadow Steppe ◽  
Temperate Steppe ◽  
Area Index ◽  
Grassland Ecosystems ◽  
Alpine Shrub

Abstract. This study compared carbon dioxide (CO2) fluxes over three grassland ecosystems in China, including a temperate semiarid steppe in Inner Mongolia (NMG), an alpine shrub-meadow in Qinghai (HB), and an alpine meadow-steppe in Tibet (DX). Measurements were made in 2004 and 2005 using the eddy covariance technique. Objectives were to document the seasonality of the net ecosystem exchange of CO2 (NEE) and its components, gross ecosystem photosynthesis (GEP), and ecosystem respiration (Reco), and to examine how environmental factors affect the CO2 exchange in these grassland ecosystems. The 2005 growing season (from May to September) was warmer than that of 2004 across the three sites, and precipitation in 2005 was less than that in 2004 at NMG and DX. The magnitude of CO2 fluxes (daily and annual sums) was largest at HB, which also showed the highest temperature sensitivity of Reco among the three sites. A stepwise multiple regression analysis showed that the seasonal variation of GEP, Reco, and NEE of the alpine shrub-meadow was mainly controlled by air temperature, whereas leaf area index can likely explain the seasonal variation in GEP, Reco, and NEE of the temperate steppe. The CO2 fluxes of the alpine meadow-steppe were jointly affected by soil moisture and air temperature. The alpine shrub-meadow acted as a net carbon sink over the two study years, whereas the temperate steppe and alpine meadow-steppe acted as net carbon sources. Both GEP and Reco were reduced by the summer and spring drought in 2005 at NMG and DX, respectively. The accumulated leaf area index during the growing season (LAIsum) played a key role in the interannual and intersite variation of annual GEP and Reco across the study sites and years, whereas soil moisture contributed most significantly to the variation in annual NEE. Because LAIsum was significantly correlated with soil moisture at a depth of 20 cm, we concluded that the available soil moisture other than annual precipitation was the most important factor controlling the variation in the CO2 budgets of different grassland ecosystems in China.

scholarly journals Emisi gas rumah kaca, cadangan karbon serta strategi adaptasi dan mitigasi pada perkebunan kopi rakyat di Nusa Tenggara Barat (Greenhouse gas emission, carbon stock, adaptation and mitigation strategies at smallholder coffee plantation in West Nusa Tenggara)

2018 ◽  
Vol 86 (2) ◽  
Author(s):  
Ali PRAMONO ◽  
. SADMAKA
Keyword(s):  
Climate Change ◽  
Carbon Stock ◽  
Ghg Emissions ◽  
Agricultural Practices ◽  
Carbon Stocks ◽  
Mitigation Strategies ◽  
Coffee Plantation ◽  
Ghg Mitigation ◽  
Coffee Plantations ◽  
Adaptation And Mitigation

Global warming and climate change are the world's major environmental, social and economic problems. The agricultural sector can act as an affected victim, greenhouse gas (GHG) contributor, and GHG absorber. Plantations have a very strategic role in the national action plan in GHG mitigation, because it has a great ability to absorb CO2. Therefore, it is necessary to determine the carbon stocks and GHG emissions from plantation management. The objectivesof the study wereto measure GHG emissions,to determine carbon stocks,and to define adaptation and mitigation strategies on climate change in existing coffee plantation systems. Gas samples were taken from 5 sampling points as replications by closedchamber method. Carbon stock estimation was done by destructive technique, including biomass of understorey and non-wood necromass. The results showed that the coffee plantations less than 10 years-oldat the study sites emitted 47 tons CO2-e/ha/year and stored carbon of 91.4 tons C/ha. Climate change adaptation strategies can be done by the application of good agricultural practices (GAP)andthe use of drought-tolerantclones, mulches,shade trees,multiple cropping systems, silt pitsand biophore techniques. The GHG mitigation can be done by the utilization of plantation waste as a source of organic fertilizer, biochar, animal feed, and bioenergy sources through the development of models of integration crop and livestock systems, as well as rejuvenation of plantation crops to increase carbon sinks and stocks.  [Keywords: climate change, carbon sequestration, coffee plantations] Abstrak Pemanasan global dan perubahan iklim menjadi masalah utama lingkungan, sosial dan ekonomi dunia hingga saat ini. Sektor pertanian dapat berperan sebagai korban terdampak, penyumbang Gas Rumah Kaca (GRK), dan penyerapGRK. Tanaman perkebunan mempunyai posisi sangat strategis dalam rencana aksi nasional di sektor pertanian, karena memiliki kemampuan besar dalam menyerap CO2. Oleh karena itu, pengukuran cadangan karbon dan emisi GRK dari pengelolaan perkebunan perlu dilakukan. Tujuan penelitian adalah untuk mengukur emisi GRK, menentukan cadangan karbon dan menetapkan strategi adaptasi dan mitigasi terhadap perubahan iklim pada sistem perkebunan kopi rakyat eksisting di Propinsi Nusa Tenggara Barat. Pengambilan contoh gas dilakukan di limatitik sampling dengan metode sungkup tertutup. Penghitungan cadangan karbon di atas permukaan tanah dilakukan dengan cara destruktifyang mencakup juga penetapan cadangan karbon biomassatanaman bawah dan biomassaserasah (ne-kromas non kayu). Hasil penelitian menunjukkan bahwa perkebunan kopi rakyat yang berumur kurang dari 10 tahun di lokasi penelitianmeng-emisikan karbon sebesar 47 ton CO2-e/ha/tahundan menyimpan cadangankarbon sebesar 91,4ton C/ha. Strategi adaptasi terhadap perubahan iklim dapat dilakukan dengan penerapan praktik Pertanian yang baik/ Good Agricultural Practices(GAP), penggunaan klon tahan kekeringan, penggunaan mulsa organik, pemanfaatanpohon penaungdan sistem tumpang sari, pembuatan rorak dan biopori.Mitigasi GRK dapat dilakukan dengan pemanfaatan limbah tanaman perkebunan sebagai sumber pupukorganik, arang (biochar), pakan ternak, dan sumber bioenergimelalui pengem-bangan model sistem integrasi tanaman dan ternak,serta peremajaan tanaman perkebunan yang sudah menurun produktivitasnya untuk meningkatkan serapan dan cadangankarbon. [Kata kunci :perubahan iklim, sekuestrasi karbon, perkebunan kopi]

Soil carbon dioxide emissions in eggplants based on cover crop residue management

2020 ◽  
Vol 118 (1) ◽  
pp. 39-55 ◽  
Author(s):  
Emanuele Radicetti ◽  
Enio Campiglia ◽  
Alireza Safahani Langeroodi ◽  
József Zsembeli ◽  
Nóra Mendler-Drienyovszki ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Soil Carbon ◽  
Cover Crop ◽  
Carbon Dioxide Emissions ◽  
Crop Residue ◽  
Residue Management ◽  
Soil Carbon Dioxide ◽  
Crop Residue Management

scholarly journals Contrasting carbon dioxide fluxes between a drying shrub wetland in Northern Wisconsin, USA, and nearby forests

2009 ◽  
Vol 6 (6) ◽  
pp. 1115-1126 ◽  
Author(s):  
B. N. Sulman ◽  
A. R. Desai ◽  
B. D. Cook ◽  
N. Saliendra ◽  
D. S. Mackay
Keyword(s):  
Carbon Dioxide ◽  
Water Table ◽  
Climate Models ◽  
Ecosystem Respiration ◽  
Net Ecosystem Exchange ◽  
Carbon Dioxide Exchange ◽  
Co2 Fluxes ◽  
Carbon Dioxide Fluxes ◽  
Highly Correlated ◽  
Shrub Wetland

Abstract. Wetland biogeochemistry is strongly influenced by water and temperature dynamics, and these interactions are currently poorly represented in ecosystem and climate models. A decline in water table of approximately 30 cm was observed at a wetland in Northern Wisconsin, USA over a period from 2001–2007, which was highly correlated with an increase in daily soil temperature variability. Eddy covariance measurements of carbon dioxide exchange were compared with measured CO2 fluxes at two nearby forests in order to distinguish wetland effects from regional trends. As wetland water table declined, both ecosystem respiration and ecosystem production increased by over 20% at the wetland, while forest CO2 fluxes had no significant trends. Net ecosystem exchange of carbon dioxide at the wetland was not correlated with water table, but wetland evapotranspiration decreased substantially as the water table declined. These results suggest that changes in hydrology may not have a large impact on shrub wetland carbon balance over inter-annual time scales due to opposing responses in both ecosystem respiration and productivity.

scholarly journals Effect of Mineral N on C and N Dynamics of Rice and Wheat Residues under Different Moisture Levels

2020 ◽  
Vol 63 (3) ◽  
pp. 226-237
Author(s):  
Ljaz Ali ◽  
Ghulam Nabi
Keyword(s):  
Soil Moisture ◽  
Crop Residue ◽  
Crop Residues ◽  
Moisture Level ◽  
Residue Management ◽  
High Moisture ◽  
Mineral N ◽  
N Dynamics ◽  
High Moisture Level ◽  
C And N

Crop residue mineralization affects soil carbon (C) and nitrogen (N) dynamics during crop residue management in crop production. C and N mineralization dynamics of rice and wheat residues incorporated with and without mineral N under two moisture conditions were evaluated under laboratory conditions. Mineral N was applied @ 0.015 g/Kg (»30 Kg/ha), whereas soil moisture was maintained at high (» – 15 KPa, near field capacity) and at low (» – 500 KPa)moisture levels during course of study.Periodic determinations on CO2 – C and N mineralized were performed over a period of 120 days. The highest peaks for CO2 – C occurred during first week of the study which then reduced gradually until it attained an equilibrium. High moisture level enhanced CO2 – C flux by 14% than low moisture level. Combined application of crop residues and mineral N released 17% more CO2 – C than crop residue treatments without mineral N.In residue applied treatments, immobilization was 40% higher at high moisture level than that at low moisture level. Application of rice and wheat residues in combination with mineral N caused both immobilizations followed by mineralization phases at both moisture levels. At high moisture level, maximum immobilization occurred during initial 15 days, while at low moisture level it continued till about 30 days. After day15, mineralization started which continued to increase during remaining period of study at high moisture and at low moisture mineralization initiated from day 60 onward. Mineralization in rice residue was faster than that in wheat residues. Immobilization of N continued progressively in residue alone treated soils at both moisture levels during study period. In residue treated soils, increase in soil moisture increased soil organic carbon (SOC) and soil water stable aggregates (WSA) significantly by 14% and 55% over control respectively.Combined application of crop residues and mineral N increased SOC by 43% and WSA by 59%. This study indicated that incorporation of crop residues along with addition of mineral N in the presence of optimum moisture promoted its faster decomposition with a quicker mineral N release, more organic matter build up and soil structure improvement than crop residues incorporated without mineral N. 

scholarly journals Controls of carbon dioxide concentrations and fluxes above central London

2011 ◽  
Vol 11 (5) ◽  
pp. 1913-1928 ◽  
Author(s):  
C. Helfter ◽  
D. Famulari ◽  
G. J. Phillips ◽  
J. F. Barlow ◽  
C. R. Wood ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Atmospheric Stability ◽  
Co2 Fluxes ◽  
Night Time ◽  
Flux Footprint ◽  
Carbon Dioxide Fluxes ◽  
Emissions Inventory ◽  
Building Height ◽  
Street Level ◽  
Significant Difference

Abstract. Eddy-covariance measurements of carbon dioxide fluxes were taken continuously between October 2006 and May 2008 at 190 m height in central London (UK) to quantify emissions and study their controls. Inner London, with a population of 8.2 million (~5000 inhabitants per km2) is heavily built up with 8% vegetation cover within the central boroughs. CO2 emissions were found to be mainly controlled by fossil fuel combustion (e.g. traffic, commercial and domestic heating). The measurement period allowed investigation of both diurnal patterns and seasonal trends. Diurnal averages of CO2 fluxes were found to be correlated with traffic but also exhibited an inverse dependency on atmospheric stability in the near-neutral range, with higher fluxes coinciding with unstable stratification during most seasons and perhaps reflecting how changes in heating-related natural gas consumption and, to a lesser extent, photosynthetic activity controlled the seasonal variability. Despite measurements being taken at ca. 22 times the mean building height, coupling with street level was adequate, especially during daytime. Night-time saw a higher occurrence of stable or neutral stratification, especially in autumn and winter, which resulted in data loss in post-processing and caused the tower to become decoupled from street level. CO2 fluxes observed at night were not always correlated with traffic counts, probably reflecting this decoupling, but also the fact that at night heating was always a larger source than traffic. No significant difference was found between the annual estimate of net exchange of CO2 for the expected measurement footprint and the values derived from the National Atmospheric Emissions Inventory (NAEI), with daytime fluxes differing by only 3%. This agreement with NAEI data also supported the use of the simple flux footprint model which was applied to the London site; this also suggests that individual roughness elements did not significantly affect the measurements due to the large ratio of measurement height to mean building height.

scholarly journals Tower and Aircraft Eddy Covariance Measurements of Water Vapor, Energy, and Carbon Dioxide Fluxes during SMACEX

2005 ◽  
Vol 6 (6) ◽  
pp. 954-960 ◽  
Author(s):  
J. H. Prueger ◽  
J. L. Hatfield ◽  
T. B. Parkin ◽  
W. P. Kustas ◽  
L. E. Hipps ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Water Vapor ◽  
Eddy Covariance ◽  
Spatial And Temporal Variability ◽  
Co2 Fluxes ◽  
Sensible Heat ◽  
Carbon Dioxide Fluxes ◽  
Crop Growth Stage ◽  
Aircraft Flux Measurements ◽  
Carbon Dioxide Co2

Abstract A network of eddy covariance (EC) and micrometeorological flux (METFLUX) stations over corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] canopies was established as part of the Soil Moisture–Atmosphere Coupling Experiment (SMACEX) in central Iowa during the summer of 2002 to measure fluxes of heat, water vapor, and carbon dioxide (CO2) during the growing season. Additionally, EC measurements of water vapor and CO2 fluxes from an aircraft platform complemented the tower-based measurements. Sensible heat, water vapor, and CO2 fluxes showed the greatest spatial and temporal variability during the early crop growth stage. Differences in all of the energy balance components were detectable between corn and soybean as well as within similar crops throughout the study period. Tower network–averaged fluxes of sensible heat, water vapor, and CO2 were observed to be in good agreement with area-averaged aircraft flux measurements.

Sign in / Sign up

Export Citation Format

Share Document