Photoautotrophic microorganisms as a carbon source for temperate soil invertebrates

We tested experimentally if photoautotrophic microorganisms are a carbon source for invertebrates in temperate soils. We exposed forest or arable soils to a 13 CO 2 -enriched atmosphere and quantified 13 C assimilation by three common animal groups: earthworms (Oligochaeta), springtails (Hexapoda) and slugs (Gastropoda). Endogeic earthworms ( Allolobophora chlorotica ) and hemiedaphic springtails ( Ceratophysella denticulata ) were highly 13 C enriched when incubated under light, deriving up to 3.0 and 17.0%, respectively, of their body carbon from the microbial source in 7 days. Earthworms assimilated more 13 C in undisturbed soil than when the microbial material was mixed into the soil, presumably reflecting selective surface grazing. By contrast, neither adult nor newly hatched terrestrial slugs ( Deroceras reticulatum ) grazed on algal mats. Non-photosynthetic 13 CO 2 fixation in the dark was negligible. We conclude from these preliminary laboratory experiments that, in addition to litter and root-derived carbon from vascular plants, photoautotrophic soil surface microorganisms (cyanobacteria, algae) may be an ecologically important carbon input route for temperate soil animals that are traditionally assigned to the decomposer channel in soil food web models and carbon cycling studies.

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DEGRADASI LAHAN PADA KEBUN CAMPURAN DAN TEGALAN DI KABUPATEN DHARMASRAYA

Jurnal Solum ◽

10.25077/js.4.1.5-9.2007 ◽

2007 ◽

Vol 4 (1) ◽

pp. 5

Author(s):

Syafrimen Yasin ◽

Gusnidar Gusnidar ◽

Dedy Iskandar

Keyword(s):

Land Use ◽

Soil Depth ◽

Soil Surface ◽

Soil Samples ◽

Imperata Cylindrica ◽

Undisturbed Soil ◽

Fertility Status ◽

Land Use Types ◽

Bulk Volume ◽

Soil Fertility Status

A research conducted in Sungai Rumbai, Dharmasraya Regency and in Soil Laboratory Andalas university was aimed to evaluate soil fertility status on the depth below 0-20 cm from several land use types , especially under Mixed Garden and annual cultivated dryland soil. Soil samples were taken on Ultisol at 0-8% slope (late-waving soil surface). Land use types evaluated were forest, annual cultivated dryland, bush land, rangeland covered by Imperata cylindrica and mixed garden. Composite soil samples for soil chemical analysis were taken on the 0-20 cm soil depth with four replications, and 5 drillings for each replication. Undisturbed soil samples by using sample ring were used to analyze sol bulk volume. The data resulted were compared to the criteria and were statistically tested using Analysis of Variance and then were continued by LSD at 5% level. From the results of analyses could be concluded that land use for mixed garden had the higher Organic Carbon (OC) content and the lower bulk volume (BV) than those for annual cultivated dryland soil.Key Words: Degradasi Lahan, Kebun Campuran, Tegalan

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Nitrogen application timing and soil inorganic nitrogen dynamics under no-till oat/maize sequential cropping

Revista Brasileira de Ciência do Solo ◽

10.1590/s0100-06832006000400011 ◽

2006 ◽

Vol 30 (4) ◽

pp. 707-714 ◽

Cited By ~ 5

Author(s):

Jeferson Dieckow ◽

Egon José Meurer ◽

Roberto Luiz Salet

Keyword(s):

Inorganic Nitrogen ◽

N Uptake ◽

Soil Surface ◽

Undisturbed Soil ◽

N Application ◽

Residue Decomposition ◽

No Till ◽

Maize Plants ◽

N Immobilisation ◽

Sequential Cropping

The timing of N application to maize is a key factor to be considered in no-till oat/maize sequential cropping. This study aimed to evaluate the influence of pre-planting, planting and sidedress N application on oat residue decomposition, on soil N immobilisation and remineralisation and on N uptake by maize plants in no-till oat/maize sequential cropping. Undisturbed soil cores of 10 and 20 cm diameter were collected from the 0-15 cm layer of a no-till Red Latossol, when the oat cover crop was in the milk-grain stage. Two greenhouse experiments were conducted simultaneously. Experiment A, established in the 10 cm diameter cores and without plant cultivation, was used to asses N dynamics in soil and oat residues. Experiment B, established in the 20 cm diameter cores and with maize cultivation, was used to assess plant growth and N uptake. An amount of 6.0 Mg ha-1 dry matter of oat residues was spread on the surface of the cores. A rate of 90 kg N ha-1 applied as ammonium sulphate in both experiments was split in pre-planting, planting and sidedress applications as follows: (a) 00-00-00 (control), (b) 90-00-00 (pre-planting application, 20 days before planting), (c) 00-90-00 (planting application), (d) 00-30-60 (split in a planting and a sidedress application 31 days after emergence), (e) 00-00-00* (control, without oat residue) and (f) 90-00-00* (pre-planting application, without oat residue). The N concentration and N content in oat residues were not affected during decomposition by N fertilisation. Most of the fertiliser NH4+-N was converted into NO3--N within 20 days after application. A significant decrease in NO3--N contents in the 0-4 cm layer was observed in all treatments between 40 and 60 days after the oat residue placement on the soil surface, suggesting the occurrence of N immobilisation in this period. Considering that most of the inorganic N was converted into NO3- and that no immobilisation of the pre planting fertiliser N occurred at the time of its application, it was possible to conclude that pre-planting applied N was prone to losses by leaching. On the other hand, with split N applications, maize plants showed N deficiency symptoms before sidedress application. Two indications for fertiliser-N management in no-till oat/maize sequential cropping could be suggested: (a) in case of split application, the sidedress should be earlier than 30 days after emergence, and (b) if integral application is preferred to save field operations, this should be done at planting.

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Surface runoff, soil and nutrient losses from farming systems in the Australian semi-arid tropics

Australian Journal of Experimental Agriculture ◽

10.1071/ea9961003 ◽

1996 ◽

Vol 36 (8) ◽

pp. 1003 ◽

Cited By ~ 19

Author(s):

M Dilshad ◽

JA Motha ◽

LJ Peel

Keyword(s):

Surface Runoff ◽

Soil Conservation ◽

Soil Loss ◽

Soil Surface ◽

Farming Systems ◽

Surface Characteristics ◽

Control Surface ◽

Arable Soils ◽

North West ◽

Semi Arid

Most soils suitable for dryland agriculture in north-west Australia occur in the Daly Basin. These are sesquioxidic soils which include red, yellow and grey earths, and soils related to yellow and red earths. The potential, for these arable soils to be degraded by highly erosive rainfalls, common to the region, is high. Farming practices strongly influence the soil surface characteristics (vegetation cover, roughness, soil strength), which in turn control surface runoff, and sediment detachment and transport. In studies conducted during 1984-89 in the Daly Basin, conventionally tilled catchments, produced 1.5-2 times more runoff and lost 1.5-6 times more soil than their no-tillage counterparts (all catchments were within soil conservation banks). In these conventionally tilled catchments, soil loss was <8.1 t/ha.year. Other studies in the region have shown that, without soil conservation banks, soil loss can be around 100/ha.year under conventional tillage. Little work, however, has been undertaken on farms in the Australian semi-arid tropics to study the movement of nutrients and herbicides (in ionic and adsorbed forms) and further research is warranted.

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Root development in seedlings of ryegrass (Lolium perenne L.) and phalaris (Phalaris aquatica L.) sown onto the soil surface

Australian Journal of Agricultural Research ◽

10.1071/ar9820665 ◽

1982 ◽

Vol 33 (4) ◽

pp. 665 ◽

Cited By ~ 4

Author(s):

PS Cornish

Keyword(s):

Root Development ◽

Soil Surface ◽

Undisturbed Soil ◽

Growth And Survival ◽

Small Vessels ◽

Nodal Roots ◽

Nodal Root ◽

Seminal Roots ◽

Surface Drying ◽

Axial Resistance

The effects of surface-sowing on root type, number and xylem radius were studied in relation to the seedling growth and survival of ryegrass and phalaris. Under optimal conditions in a growth cabinet, both species produced primary and lateral seminal roots, nodal roots and, in the absence of light, a subcoleoptile internode (s.c.i.). Phalaris had fewer lateral seminal roots and, in this species, internodal roots occurred along the s.c.i. Surface placement per se had no effect on any of the measured parameters of root development, but surface drying prevented nodal root primordia from extending, even when plants were otherwise supplied with water. This effect of surface drying on nodal root development was confirmed in a glasshouse study using undisturbed soil cores (30 by 60 cm) to simulate field conditions. Phalaris was less likely than ryegrass to produce nodal roots after surface sowing. The effective xylem radius (re) of the primary seminal root was 7.9 �m in ryegrass and 11.6 �m in phalaris. Calculations using the Poiseuille equation indicated that the axial resistance to water flow through these roots would greatly restrict seedling water uptake and growth in the absence of other roots. Lateral seminal roots and internodal roots had small vessels which could not significantly reduce the axial resistance to flow. Good seedling water relations in both species therefore depend on early development of the nodal roots which contain large xylem vessels (re > 16 �m). It was concluded that the effect of soil-surface drying on nodal root development was likely to account for some cases of poor vigour and survival of surface-sown grasses.

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The influence of soil structure and air content on gas diffusion in soils.

Netherlands Journal of Agricultural Science ◽

10.18174/njas.v18i1.17354 ◽

1970 ◽

Vol 18 (1) ◽

pp. 37-48

Author(s):

J.W. Bakker ◽

A.P. Hidding

Keyword(s):

Diffusion Coefficient ◽

Soil Structure ◽

Soil Surface ◽

Ambient Air ◽

Gas Diffusion ◽

Undisturbed Soil ◽

Air Content ◽

Temperature And Pressure ◽

Storage Term ◽

Puddled Soil

A method is described of determining the diffusion coefficient of O2 in undisturbed soil samples. Calculations were made of errors involved when neglecting the storage term, temperature and pressure variations, O2 consumption and resistance of ambient air. The diffusion coefficient (Ds) is a function of air porosity (eg) and soil structure. At values of eg below 0.2, the effect of a puddled soil surface becomes evident. In puddled soils values of Ds at equal eg are far below those in non-puddled soils and the differences increase with decreasing eg. A wet soil crust can severely limit gas exchange by diffusion. (Abstract retrieved from CAB Abstracts by CABI’s permission)

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Using Nematode Community to Evaluate Banana Soil Food Web in Mekargalih, Cianjur, West Java

Pertanika Journal of Tropical Agricultural Science ◽

10.47836/pjtas.44.2.12 ◽

2021 ◽

Vol 44 (2) ◽

Author(s):

Dale Akbar Yogaswara ◽

Hikmat Kasmara ◽

Wawan Hermawan

Keyword(s):

Food Web ◽

Profile Analysis ◽

Biological Indicator ◽

Nematode Community ◽

Trophic Levels ◽

Maturity Index ◽

Soil Nematode ◽

Soil Food Web ◽

Undisturbed Soil ◽

Decomposition Pathway

Soil biota is very diverse and contributes widely to ecosystem services that are important in the sustainable function of natural and managed ecosystems. Knowing the condition of the soil food web through the communities that inhabit it is necessary to assess the productivity of the soil. Nematode communities in the soil food web can be used as indicators because of their high abundance, and they inhabit various trophic levels, and participate in several important processes in the soil. The soil food web condition from three locations (Agr1, Agr2, Agr3) through the nematode functional index was evaluated using the maturity index (MI), the maturity index 2-5 (MI-25), the plant-parasitic index (PPI), the channel index (CI), the enrichment index (EI), the structure index (SI), and the basal index (BI). Nematode diversity was evaluated using Simpson’s index of diversity, dominance, and evenness. The MI and MI2-5 scores indicated that Agr3 (3.81) had an undisturbed food web, while Agr2 (2.88 and 3.0) and Agr1 (2.5 and 2.51) were in a moderate condition with minor disturbances. Fauna profile analysis using SI and EI shows that Agr3 and Agr1 had an undisturbed soil food web, and Agr2 was in enriched conditions. CI results found that Agr1 and Agr3 had a fungal decomposition pathway while Agr2 had a bacterial decomposition pathway. We concluded from this research, that prospect of the nematode community to serve as a collection of biological indicator data in assessing soil or ecosystem health can be considered in further research.

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Influence of environmental factors on the germination of barley grass (Hordeum glaucum) and annual ryegrass (Lolium rigidum)

Australian Journal of Experimental Agriculture ◽

10.1071/ea9870525 ◽

1987 ◽

Vol 27 (4) ◽

pp. 525 ◽

Cited By ~ 2

Author(s):

PM Kloot

Keyword(s):

Physical State ◽

Soil Surface ◽

Soil Disturbance ◽

Chemical Characteristics ◽

Field Observations ◽

Soil Cores ◽

Annual Ryegrass ◽

Alkaline Soils ◽

Lolium Rigidum ◽

Undisturbed Soil

The ability of Hordeum glaucum to germinate and initially grow faster than Lolium rigidum was found to be influenced by the soil's physical state and its chemical characteristics. Glasshouse studies showed that the replacement of Lolium by Hordeum in undisturbed situations was due to the advantage of the latter having awned florets which anchor and lever the seed on smooth, compacted surfaces. Soil disturbance produces a broken surface upon which Hordeum has no advantage over Lolium. Hordeum is also able to germinate under higher osmotic pressures than is Lolium. Higher osmotic pressures will arise on stock camps and on alkaline soils where the salts are of biological and pedological origin respectively. Glasshouse and field observations showed that the top 3 mm of the soil surface are drier and more saline than the soil profile generally as indicated from measurements on soil cores. In undisturbed soil this surface layer will favour the dominance of Hordeum over Lolium. In cultivated soil the layer will be diluted throughout the depth of cultivation.

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Detection of Changes in Arable Chernozemic Soil Health Based on Landsat TM Archive Data

Remote Sensing ◽

10.3390/rs13122411 ◽

2021 ◽

Vol 13 (12) ◽

pp. 2411

Author(s):

Igor Savin ◽

Elena Prudnikova ◽

Yury Chendev ◽

Anastasia Bek ◽

Dmitry Kucher ◽

...

Keyword(s):

Soil Moisture ◽

Satellite Data ◽

Survey Methods ◽

Humus Content ◽

Arable Land ◽

Soil Health ◽

Soil Surface ◽

Soil Conditions ◽

Moisture Regime ◽

Arable Soils

When soils are used for a long period of time as arable land, their properties change. This can lead to soil degradation and loss of fertility, as well as other important soil biosphere functions. Obtaining data on the trends in arable soil conditions over large areas using traditional field survey methods is expensive and time-consuming. Currently, there are large archives of satellite data that can be used to monitor the status of arable soils. The analysis of changes in the color of the surface of arable chernozem soils of the Belgorod region, for the period from 1985 to the present, has been carried out based on the analysis of Landsat TM5 satellite data and information about the spectral reflectance of the soils of the region. It is found that, on most parts of arable lands of the region, the color of the soil surface has not changed significantly since 1985. Color changes were revealed on 11% of the analyzed area. The greatest changes are connected with the humus content and moisture content of soils. The three most probable reasons for the change of humus content in an arable horizon of soils are as follows: the dehumidification of soils during plowing; the reduction of the humus content due to water erosion; and the increase in humus content due to changes in the land-use system of the region in recent years. The change in soil moisture regime has mainly been found in arable lands in river valleys, most likely conditioned by the natural evolution of soils. Trends of increasing soil moisture are prevalent. The revealed regularities testify to the high stability of arable soils in the region during the last few decades.

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PENCUCIAN BAHAN ORGANIK TANAH PADA TIGA PENGGUNAAN LAHAN DI DAERAH HUTAN HUJAN TROPIS SUPER BASAH PINANG-PINANG GUNUNG GADUT PADANG

Jurnal Solum ◽

10.25077/js.8.1.34-42.2011 ◽

2011 ◽

Vol 8 (1) ◽

pp. 34

Author(s):

Yulnafatmawita Yulnafatmawita ◽

Adrinal Adrinal ◽

Arief Fauzan Hakim

Keyword(s):

Land Use ◽

Land Use Change ◽

Rain Forest ◽

Tropical Rain Forest ◽

Soil Surface ◽

Soil Samples ◽

Annual Rainfall ◽

Undisturbed Soil ◽

Physical Laboratory ◽

West Sumatra

Study about soil organic matter (SOM) leaching in soil profiles of tropical rain forest was conducted in Bukit Pinang-Pinang, the upper footslope of Mt. Gadut in West Sumatra, and in Soil Physical laboratory Andalas University Padang. Bukit Pinang-Pinang is located on 480-640 m asl and geographically is between 100°29’40” and 100°30’20 E” as well as between 0°54’55” and 0°55’45”S. This rain forest area is known as a super wet area because it receives high annual rainfall (>3500 mm). The objective of this research was to measure the amount of SOM leached from top soil into the deeper soil. Undisturbed soil samples were taken from three different land uses, forest, bush, and mixed garden, on the top, middle, and foot slopes. Undisturbed soil samples were leached with distilled water as the amount of rainfall accepted in natural condition. The results showed that, land use change from forest into ecosystems of mixed garden (for over 50 years with 100% soil surface coverage and without any cultivation) and bush land (for over 20 years left) did not cause the SOM content in the profiles decreased. Amount of SOM leached from the top 0-10 cm was found greater from mixed garden, then followed by forest on the upper slope, forest on the middle slope, and bush area.Keywords: SOM leaching, land use change, tropical rain forest, bush, mixed garden

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Prospective upscaling of quantification of non-rainfall water inputs to regional scale

10.5194/egusphere-egu2020-12486 ◽

2020 ◽

Author(s):

Nurit Agam ◽

Dilia Kool

Keyword(s):

Diurnal Cycle ◽

Land Surface ◽

Regional Scale ◽

Broad Band ◽

Soil Layer ◽

Soil Surface ◽

Heat Fluxes ◽

Surface Emissivity ◽

Undisturbed Soil ◽

Small Magnitude

In drylands, the annual amount of non-rainfall water inputs (NRWIs), i.e., a gain of water to the surface soil layer that is not caused by rainfall, can exceed that of rainfall.&#160; They thus significantly contribute to the water cycle and to biogeochemical dynamics.&#160; However, the small magnitude of the fluxes involved in the formation and evaporation of NRWIs challenges their measurement.&#160; Various methods were applied in attempting to quantify NRWIs amount and duration, all being point/local measurements.&#160; Given the large heterogeneity of soils, both at local and at regional scale, upscaling from the small point measurement methods to larger scales is necessary in order to fully understand the environmental factors controlling NRWIs and the role of NRWIs in dryland ecosystems.&#160; Numerous remote sensing-based models have been developed to assess spatially distributed latent heat fluxes, greatly varying in complexity.&#160; Unfortunately, the magnitude of diurnal fluxes due to NRWIs is too small to be detected by any of the existing models. &#160;Hypothesizing that soil surface emissivity is sensitive to very small changes in water content at the top soil layer, our objective was to quantify NRWIs by analyzing the temporal changes in land surface emissivity over bare loess soil in the Negev desert, Israel.&#160; Proven successful, this can be utilized over large areas.&#160;Intensive measurements using a longwave infrared radiometer (CLIMAT 312-2n ASTER, Cimel Electronique, Paris, France) were conducted in summer 2019 at the Wadi Mashash Experimental Farm (31o08&#8217;N, 34o53&#8217;E). &#160;Radiance and temperature measurements were obtained for a broad band (8.01-13.34 &#956;m) and 5 subsections of this bandwidth.&#160; The radiometer was mounted at 0.5 m directly above one of four microlysimeters (undisturbed soil samples installed flash with the soil surface and weighed continuously).&#160; Radiometer readings were automatically taken every 15 min for 24-h cycles.&#160;Initial results indicate an agreement between the diurnal cycle of NRWIs detected by the microlysimeters and between the diurnal cycle of an index derived from the radiometer bands: (e11.3-e8.3)/ e10.6 (the numbers are the center of the band in &#181;m).&#160; These preliminary results show the potential to upscale quantifying NRWIs to regional scale.

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