145,737 research outputs found

    Water, rather than temperature, dominantly impacts how soil fauna affect dissolved carbon and nitrogen release from fresh litter during early litter decomposition

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    Longstanding observations suggest that dissolved materials are lost from fresh litter through leaching, but the role of soil fauna in controlling this process has been poorly documented. In this study, a litterbag experiment employing litterbags with different mesh sizes (3 mm to permit soil fauna access and 0.04 mm to exclude fauna access) was conducted in three habitats (arid valley, ecotone and subalpine forest) with changes in climate and vegetation types to evaluate the effects of soil fauna on the concentrations of dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) during the first year of decomposition. The results showed that the individual density and community abundance of soil fauna greatly varied among these habitats, but Prostigmata, Isotomidae and Oribatida were the dominant soil invertebrates. At the end of the experiment, the mass remaining of foliar litter ranged from 58% for shrub litter to 77% for birch litter, and the DOC and TDN concentrations decreased to 54%-85% and increased to 34%-269%, respectively, when soil fauna were not present. The effects of soil fauna on the concentrations of both DOC and TDN in foliar litter were greater in the subalpine forest (wetter but colder) during the winter and in the arid valley (warmer but drier) during the growing season, and this effect was positively correlated with water content. Moreover, the effects of fauna on DOC and TDN concentrations were greater for high-quality litter and were related to the C/N ratio. These results suggest that water, rather than temperature, dominates how fauna affect the release of dissolved substances from fresh litter

    Soil nematode communities in grasslands

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    This thesis summarizes the results of five studies investigating the effect of plant species on soil nematode communities in grasslands. Nematodes (roundworms) are ubiquitous members of the soil fauna and have been much used as indicators of soil conditions. Plants have the ability to affect soil organisms through structural modification of the soil habitat and through the quantity and quality of organic matter that is returned to soil, in the form of plant litter and root exudates. The influence of grassland plant species on the soil nematode fauna was investigated in an experimental grassland, a glasshouse experiment and in a semi-natural grassland. Monocultures of 12 grassland plant species belonging to three plant functional groups, viz. grasses, legumes and non-leguminous forbs, were investigated in the field experiment and a subset of these in the other two systems. Plant species effects were common, for example, plant feeding and bacterial feeding nematodes responded positively to legumes and grasses, while forbs enhanced fungal feeding nematodes. Plant species identity appeared to be much more important than plant functional group for the nematode fauna. The effects of plants were quite consistent between field and glasshouse experiments. The influence of plant species diversity and functional diversity on the nematode fauna was investigated in the experimental grassland. Plant species composition proved to be more important for soil nematode communities than any of the plant diversity measures, but the hypothesis that species or functional diversity of plants affect nematode diversity or composition could not be rejected. My results also suggest that plant species identity may be an important determinant of spatial structure in natural grasslands. There was a succession of the nematode fauna during the eight years after establishment of the experimental grassland, especially indicated by the increase in maturity index of the nematode fauna. The results highlight the need for long-term experiments to reveal successional trends in soil nematode communities after cessation of agriculture. The increase of plant feeders with time, the slow colonization rate and the enhanced abundance of fungal feeders in soil under forbs have implications for nature restoration of former agricultural land

    Quantifying the contribution of free-living nematodes to nitrogen mineralization

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    Soil fauna are estimated to contribute to approximately 30 % of nitrogen mineralization (Verhoef ∧ Brussaard, 1990). Soil nematodes are important contributors to this process through their key trophic positions as microbial grazers. Quantification of this contribution has mostly relied on theoretical food web analyses (Hunt et al., 1987) or laboratory incubations with simplified and artificially constructed ecosystems (Ferris et al., 1998). Incubations are often performed on homogenized soil, though soil biota is known to be responsive to physical disturbance. Furthermore, sterilization typically relies on methods disruptive of soil structure (e.g. autoclaving, freezing). The aim of this experiment was to quantify the contribution of nematodes to nitrogen mineralization during incubation. Intact cores with a representative pore structure and entire nematode populations instead of single species were used. Gamma irradiation was selected as a sterilization method to remove only soil fauna, leaving the microflora and soil structure largely intact (McNamara et al., 2003)

    Consequences of Cadmium exposure on growth and reproduction across three generations of earthworm

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    Heavy metal pollution disturbs the soil ecosystem by negatively affecting soil fauna and flora. In term of biomass and activity Annelids are a very important part of the soil invertebrate community. They are one of the first organisms affected by heavy metal contamination in soil and as such are good model organisms for assessing soil contamination. The aim of this research is to observe how Cd impacts on health and reproduction in three consecutive generations of E. fetida. [...]falseOnlin

    Study of Density and Diversity of Soil Organisms Under Mature Oil Palm on Peatland

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    Penelitian ini dilaksanakan di lahan gambut pada Kebun Panai Jaya, PT Perkebunan Nusantara IV, Provinsi Sumatera Utara. Metode pengambilan sampel yang digunakan dengan cara Pit Fall Trap (untuk menjebak fauna permukaan tanah), Barlese Tullgren (untuk melihat fauna tanah yang aktif di dalam tanah) dan membuat lubang (untuk mendapatkan cacing). Metode yang mendapatkan fauna terbanyak yaitu dengan cara Pit Fall Trap. Fauna tanah berkorelasi positif terhadap suhu, kadar air dan respirasi tanah, sedangkan terhadap pH dan C/N berkorelasi negatif. Hasil penelitian menunjukkan, diantara fauna tanah pada plot penelitian, diketahui bahwa jumlah fauna yang paling mendominasi adalah semut rangrang dan diikuti oleh cacing tanah. Baik fauna tanah (makrofauna dan mesofauna) dan mikroorganisme eukariotik tanah (jamur dan bakteri) ditemukan paling banyak pada areal rumpukan kebun kelapa sawit.This study was conducted on peat land in Kebun Panai Jaya, PT Perkebunan Nusantara IV, North Sumatera province. The sampling method was Pit Fall Trap to trap ground level fauna, Barlese Tullgren to observe the active soil fauna in the soil, and making a soil hole to get the worms sample. The Pit Fall Trap could collect the highest number of the fauna. The soil fauna was positively correlated to temperature, soil moisture, and soil respiration, and it was negatively correlated to soil pH and C/ N ratio. This study showed that, among the soil fauna that found on the observed field, the dominated organisms are weaver ants and followed with earthworms. Both soil fauna (macro and mesofauna) and eukaryotic soil microorganism (fungi and bacteria) were highly found under the frond piles of oil palm plantation

    Nematodes enhance plant growth and nutrient uptake under C and N-rich conditions

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    The role of soil fauna in crucial ecosystem services such as nutrient cycling remains poorly quantified, mainly because of the overly reductionistic approach adopted in most experimental studies. Given that increasing nitrogen inputs in various ecosystems influence the structure and functioning of soil microbes and the activity of fauna, we aimed to quantify the role of the entire soil nematode community in nutrient mineralization in an experimental set-up emulating nutrient-rich field conditions and accounting for crucial interactions amongst the soil microbial communities and plants. To this end, we reconstructed a complex soil foodweb in mesocosms that comprised largely undisturbed native microflora and the entire nematode community added into defaunated soil, planted with Lolium perenne as a model plant, and amended with fresh grass-clover residues. We determined N and P availability and plant uptake, plant biomass and abundance and structure of the microbial and nematode communities during a three-month incubation. The presence of nematodes significantly increased plant biomass production (+9%), net N (+25%) and net P (+23%) availability compared to their absence, demonstrating that nematodes link below- and above-ground processes, primarily through increasing nutrient availability. The experimental set-up presented allows to realistically quantify the crucial ecosystem services provided by the soil biota

    Population and Distribution of Some Soil MesoFauna in the Inactive Tailing Deposition Areas of Freeport Indonesia, Timika-Papua

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    Soil fauna has played an important role in ecosystem functioning, especially as ecosystem engineers which contribute to soil fertility in tropical environment.  A tailing deposition area is  one habitat that has several types of soil fauna to live and growth as well as involves in the decomposition of organic matter. The objective of this study was to examine the number and distribution of soil fauna in the tailing area of Freeport Indonesia Mining and Gold Company, Timika.  The study was located in some inactive tailing deposition areas in between Double Levee  of the lowland area of ModADA (Modification Ajkwa Deposition Areas).  Samples were taken from inactive tailing as 198 of ModADA for soil and soil fauna, the Kuadran Method was used  to collecting soil fauna on the soil surface and in the soil.  There were 17 types/ordo of soil fauna in the study area and the highest number was a group of ants (Hymenoptera/Formicidae).  Population density (PD) and relative density (RD) of soil fauna (Formicidae) ranged from 0.03-2.41 Individu m-2 (PD) and 0.07-6.50% (RD).  Both PD and RD were likely to increase as the number of soil fauna increase.  The distribution of most soil fauna were found as a clump, while Pulmonata (Gastropods) were distributed normally in the tailing areas.  The number and types (ordo) of these soil fauna had showed that inactive tailing deposition areas were considered a good habitat for soil fauna.Key words: Distribution, population, soil fauna, tailing[How to Cite: Djuuna IAF. 2013. Population and Distribution of Some Soil MesoFauna in the Inactive Tailing Deposition Areas of Freeport Indonesia, Timika-Papua. J Trop Soils 18 (3): 225-229. Doi: 10.5400/jts.2013.18.3.225][Permalink/DOI: www.dx.doi.org/10.5400/jts.2013.18.3.225]REFERENCESAdianto.1993.Agricultural Biology of Animal Manure, Organic Fertilizer and Insecticides. Bandung: Penerbit Alumni (in Indonesian).Anderson JM and JS Ingram. 1993. Tropical soil biology and fertility: A Handbook of Methods, 2nd ed. CAB International. Wallingford. UK, 221 pp.Battigelli JP. 2011. Exploring the World Beneath your Feet – Soil Mesofauna as Potential Biological Indicators of Success in Reclaimed Soils.  Proceedings - Tailings and Mine Waste Vancouver, BC.Behan-Pelletier VM. 1999.Oribatid mite biodiversity in agroecosystems: role as bioindicators. Agric  Ecosyst Environ 74: 411-423. Brussard L. 1998. Soil fauna, guilds, functional groupsand ecosystem processes. Appl Soil Ecol 9: 123-136.De Ruiter PC, B Griffiths and JC Moore. 2002. Biodiversity and Stability in Soil Ecosystems: Patterns, Processes and the Effects of Disturbance. In: M Loreau, S Naeem and P Inchausti (eds.). Biodiversity and Ecosystem Functioning: a current synthesis. Oxford University Press, Oxford, UK, pp. 102-113.Djuuna IAF, H Siby and S Baan.2008. Population and Distribution of Soil Fauna on the Below ground of Forest Trees in Gunung Meja Forest Areas of Manokwari.  J Beccariana 1: 6.  Fitter AH, CA Gilligan, K Holling Worth, A Kleczkowski, RM Twyman, JW Pitchford and the Members of the Nerc Soil Biodiverrsity Programme. 2005. Biodiversity and ecosystem function in soil. Funct Ecol 19: 369-377.Hanafiah KA,  I Anas, A Napoleon and N Gofar. 2005. Biologi Tanah : Ekologi dan Makrobiologi Tanah.  Edisi 1, PT Raja Grafindo Persada. Jakarta,165 pp. (in Indonesian). Picaud F and DP Petit. 2007.Primary succession of Orthoptera on mine tailings: role of vegetation.  Ann de la Soc Entomol de France 43: 69-79Rusek J. 1998. Biodiversity of Collembola and their functional role in the ecosystem. Biodiver Conserv 7: 1207-1219.Sackett TE, AT Classen, and NJ Sanders. 2010.Linking soil food web structure to above and below ground ecosystem processes: ameta-analysis. Oikos 119: 1984-1992.Shao Y, W Zhang, J Shen, L Zhou,  H Xia, W Shu, H  Ferris  and S Fu.  2008.  Nematodes as indicators of soil recovery in tailings of a lead/zinc mine.  Soil Biol Biochem 40: 2040-2046.Suin NM. 2003.  The Ecology of Soil Fauna.  Penerbit Bumi Aksara Jakarta (in Indonesian).Sugiyarto. 2000.The Biodiversity of soil macro fauna on the different age of sengon in RPH Jatirejo, Kabupaten Kediri. Biodiversitas 1: 47-53. (in Indonesian).Sugiyarto, M Pujo and Nursihmiati.  2001. Relationship between the Soil Meso Fauna Biodiversity and Belowground Vegetation in Some Forest Trees of Jobolarangan. Biodiversitas 2: 140-145 (in Indonesian)Wallwork JA.   1970. Ecology of Soil Animals. London: Mc.Graw-Hill. 283 pp.Wallwork JA.1976.  The Distribution and Diversity of Soil Fauna.  Academic Press Inc. (London). 355 pp
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