• ecosystem
  • Quantifying these influences is important for understanding patchiness in ecosystem functions related to soil fertility and the delivery of nitrate (a cause of eutrophication in salt water) to streams and estuaries. (beslter.org)
  • We studied ecosystem-level CH4 and N2O fluxes in experimental communities assembled from two pasture soils and from combinations of 1, 3, 6, 8 or 9 species typical for these pastures. (uzh.ch)
  • We analyze these dynamics and characterize the impact of biomass harvest and N fertilization on soil biogeochemistry and ecosystem yield with an ecosystem model of intermediate complexity that couples plant and soil C and N cycles. (marquette.edu)
  • In a natural ecosystem, unaffected by human activity, most nutrients cycle between the plant and the soil in a closed loop. (coursehero.com)
  • Differences in how plants and decomposers respond to these pulses of precipitation affects biogeochemical cycling within the ecosystem. (wikipedia.org)
  • In The Soil Resource, Origin and Behaviour (1980), Jenny redefined the soil forming factors as state variables and extended the effects to ecosystem properties. (wikipedia.org)
  • Parent material and relief define the initial state for soil development, regional climate, and potential biota determine the rate at which chemical and biological transformations proceed, and time determines the reach of these processes, and their expression in ecosystem, soil, vegetation, and animal component properties. (wikipedia.org)
  • By redistributing nutrients, mixing soil layers, and creating pores in the soil, they can affect the characteristics of the soil important to the rest of the ecosystem. (wikipedia.org)
  • These environmental alterations (drier, brighter, less nutrient-rich soil) create changes to the ecosystem. (wikipedia.org)
  • The diversity and abundance of soil life exceeds that of any other ecosystem. (wikipedia.org)
  • biomass
  • Biomass harvest generates an imbalance in forest carbon (C) and nitrogen (N) cycles and the nonlinear biogeochemical responses may have long-term consequences for soil fertility and sustainable management. (marquette.edu)
  • These results highlight dynamic soil C-N cycle responses to harvest strategy that influence a range of functional characteristics, including N retention, leaching, and biomass yield. (marquette.edu)
  • Turfgrass quality and color ratings, and chlorophyll index (CI) were evaluated weekly, multispectral reflectance every two weeks, and biomass production once a month from 2008 thru 2010 to determine shoot growth rate, estimation of N content, and Total Kjeldahl Nitrogen in tissue (TKN). (ufl.edu)
  • Biomass, Soil Microbial Biomass. (wiley.com)
  • Nitrosomonas europaea, as well as populations of soil-dwelling AOB, have been shown to assimilate the carbon dioxide released by the reaction to make biomass via the Calvin Cycle, and harvest energy by oxidizing ammonia (the other product of urease) to nitrite. (wikipedia.org)
  • Free-living microfungi often function as decomposers, and contribute to soil microbial biomass. (wikipedia.org)
  • Jenny applied fundamental soil science to the problems of the day, when he wrote about "the rosy outlook that is sweeping the nation about converting biomass to alcohol and gasohol. (wikipedia.org)
  • carbon dioxide
  • Important environmental changes in the Northern United States include steadily increasing atmospheric carbon dioxide, tropospheric ozone, wet and dry deposition of nitrogen and sulfur compounds, acidic precipitation and clouds, and climate variability. (springer.com)
  • Because of a possible climatic warm-up, we do not wish to accelerate humus oxidation and the concomitant flux of carbon dioxide from soil into the atmosphere. (wikipedia.org)
  • The effect of anthropic soil conditions on arbuscular mycorrhizal fungi, and the production of glomalin by arbuscular mycorrhizal fungi are both of particular interest due to their roles in sequestering atmospheric carbon dioxide. (wikipedia.org)
  • taxa
  • Cyanobacteria Cyanobacteria are the main photosynthetic component of biological soil crusts, in addition to other photosynthetic taxa such as mosses, lichens, and green algae. (wikipedia.org)
  • fungi
  • The ratio of fungi to bacteria did not change in the N-amended soils, but the ratio of archaea to bacteria dropped from 20% to less than 1% in the N-amended plots. (wiley.com)
  • The fungal loop hypothesis suggests that soil fungi in arid ecosystems connect the metabolic activity of plants and biological soil crusts which respond to different soil moisture levels. (wikipedia.org)
  • Therefore, in arid ecosystems where precipitation falls during the hot season, fungi are likely the most important contributors to nutrient cycling due to their tolerance to temperature and ability to persist during long dry periods. (wikipedia.org)
  • In arid ecosystems, many primary producers, such as grasses and biological soil crusts, form symbioses with fungi. (wikipedia.org)
  • However, fungi are able to take up the nutrients produced by biological soil crusts at lower water potentials, and keep them in the biotic pool until larger water pulses allow plants to become active and take up those nutrients. (wikipedia.org)
  • Therefore, root-associated fungi symbiotic with plants and biological soil crusts connect the spatially- and temporally-distinct activities of crusts and plants. (wikipedia.org)
  • Free-living Fungi Microfungi in biological soil crusts can occur as free-living species, or in symbiosis with algae in lichens. (wikipedia.org)
  • Many microfungi in biological soil crusts have adapted to the intense light conditions by evolving the ability to produce melanin, and are called black fungi or black yeasts. (wikipedia.org)
  • biogeochemical
  • Research interests span many aspects of soil ecology and microbiology, Fundamentally, researchers are interested in understanding the interplay among microorganisms, fauna, and plants, the biogeochemical processes they carry out, and the physical environment in which their activities take place, and applying this knowledge to address environmental problems. (wikipedia.org)
  • ammonia
  • The ammonia is returned to the soil, allowing the nitrogen cycle. (reference.com)
  • Today, about 30% of the total fixed nitrogen is produced industrially using the Haber-Bosch process, which uses high temperatures and pressures to convert nitrogen gas and a hydrogen source (natural gas or petroleum) into ammonia. (wikipedia.org)
  • The plant provides amino acids to the bacteroids so ammonia assimilation is not required and the bacteroids pass amino acids (with the newly fixed nitrogen) back to the plant, thus forming an interdependent relationship. (wikipedia.org)
  • occurs
  • The following figure shows how the breakdown of nitrogen occurs in the soil. (lid-stormwater.net)
  • Total recovery of cover and composition occurs more rapidly in fine soil textured, moister environments (~2 years) and more slowly (>3800 years) in coarse soil textured, dry environments. (wikipedia.org)
  • humus
  • It is a well-established fact that the presence of a certain amount of humus in soil is essential to complete fertility, and it is equally well known that this organic matter, whether supplied in the form of stable or green manure, is far more effective when decomposed, or "rotted," than when fresh. (royalsocietypublishing.org)
  • This has been attributed to the soluble humus formed during the rotting, but wherein lies the peculiar merit of this soluble humus has long been a debatable point, some considering that it serves primarily as a plant nutrient, while others claim that its most important effect is upon the bacterial flora of the soil. (royalsocietypublishing.org)
  • Too much reliance must not be placed on the results obtained with these chemically prepared substances, for they are not strictly comparable with the soluble humus produced in the soil by natural processes. (royalsocietypublishing.org)
  • However, Bottomley has shown that it is possible, by inoculating peat with certain aërobic soil bacteria, and keeping it under suitable conditions, to convert it into a partially soluble humus in a comparatively short time. (royalsocietypublishing.org)
  • A similar bacterial action is taking place more slowly in every rotting manure heap and in all soils, for the longer stable and farm manures are kept, the more water-soluble brown humus can be extracted from them. (royalsocietypublishing.org)
  • The soluble humus which can be extracted from it may be justly considered to approximate more closely to the natural product than any extracts obtained by chemical processes, and the effects of this soluble humus on soil bacteria accordingly reproduce more exactly the influence of the organic matter of soils upon the bacterial flora. (royalsocietypublishing.org)
  • in grassland systems, most N is in soil humus. (coursehero.com)
  • Humus Mineral matter in plants Soil chemistry Soil biology Remineralisation Carbon cycle Nitrogen cycle White, Robert E. (October 2005). (wikipedia.org)
  • The humus capital, which is substantial, deserves being maintained because good soils are a national asset. (wikipedia.org)
  • ammonium
  • In plants that have a symbiotic relationship with rhizobia, some nitrogen is assimilated in the form of ammonium ions directly from the nodules. (wikipedia.org)
  • bacteria
  • For example, the nitrogenous wastes in animal urine are broken down by nitrifying bacteria in the soil to be used as new. (wikipedia.org)
  • Symbiotic nitrogen-fixing bacteria such as Rhizobium usually live in the root nodules of legumes (such as peas, alfalfa, and locust trees). (wikipedia.org)
  • biological
  • Human activities influence the N cycle through interacting physical, chemical and biological processes. (uiuc.edu)
  • In the bare soil between plants, biological soil crusts are often present. (wikipedia.org)
  • The fungal loop hypothesis suggests that biological soil crusts and associated microbes are able to become active after smaller water pulses compared to vascular plants, which require more water to become active. (wikipedia.org)
  • Biological soil crusts are formed in open spaces between vascular plants. (wikipedia.org)
  • Biological soil crusts are found on almost all soil types, but are more commonly found in arid regions of the world where plant cover is low and plants are more widely spaced. (wikipedia.org)
  • Across the globe, biological soil crusts can be found on all continents including Antarctica. (wikipedia.org)
  • The species composition and physical appearance of biological soil crusts vary depending on the climate, soil, and disturbance conditions. (wikipedia.org)
  • For example, biological soil crusts are more dominated by green algae on more acidic and less salty soils, whereas cyanobacteria are more favored on alkaline and haline soils. (wikipedia.org)
  • Compaction can adversely affect nearly all physical, chemical and biological properties and functions of soil. (wikipedia.org)
  • Attempts to mitigate soil compaction include biological, chemical and technical approaches. (wikipedia.org)
  • It is particularly concerned with the cycling of nutrients, formation and stabilization of the pore structure, the spread and vitality of pathogens, and the biodiversity of this rich biological community. (wikipedia.org)
  • Soil is made up of a multitude of physical, chemical, and biological entities, with many interactions occurring among them. (wikipedia.org)
  • The conversion of nitrogen can be carried out through both biological and physical processes. (wikipedia.org)
  • processes
  • The challenge is to assess the relative contributions of natural-and human-induced processes to N cycling under conditions of uncertainty. (uiuc.edu)
  • Simplified nitrogen cycle highlighting soil processes. (bgs.ac.uk)
  • Climate change will affect the hydrological cycle with changes to recharge, groundwater levels and resources and flow processes. (bgs.ac.uk)
  • These environmental factors interact in complex ways to affect plant physiological functions and soil processes in the context of forest landscapes derived from centuries of intensive land use and natural disturbances. (springer.com)
  • Hans Jenny (7 February 1899 - 9 January 1992) was a soil scientist and expert on pedology (the study of soil in its natural environment), particularly the processes of soil formation. (wikipedia.org)
  • There are many ways that the soil food web is an integral part of landscape processes. (wikipedia.org)
  • The processes of the nitrogen cycle transform nitrogen from one form to another. (wikipedia.org)
  • Many of those processes are carried out by microbes, either in their effort to harvest energy or to accumulate nitrogen in a form needed for their growth. (wikipedia.org)
  • The diagram besides shows how these processes fit together to form the nitrogen cycle. (wikipedia.org)
  • nutrients
  • Typical study results indicate that most of the heavy metals and other nutrients present in stormwater are bound in the soil substrate instead of discharged into streams or rivers. (lid-stormwater.net)
  • These earthworms increase the cycling and leaching of nutrients by breaking up decaying organic matter and spreading it into the soil. (wikipedia.org)
  • Earthworms break up decomposing matter on the surface of the soil and carry or mix it into the surrounding soil, often carrying some of the nutrients deeper into the soil, where saplings and other young plants have trouble reaching them. (wikipedia.org)
  • They often mix the nutrients into the soil, out of the reach of all but the deeper tree roots. (wikipedia.org)
  • increases
  • Bacterial community composition also shifted in the fertilized soil, with increases in the relative abundance of sequences related to the Bacteroidetes and Gemmatimonadetes , and decreases in the relative abundance of the Verrucomicrobia . (wiley.com)
  • Such vegetation reduces radiation or wind speed at the soil surface which reduces evaporation, and thus creates favorable microhabitats for other species.In addition, as plants senesce and become litter, this increases carbon and nitrogen contents in the top layers of soil under plant canopies. (wikipedia.org)
  • The resulting soil structure increases in stability with the number of interactions between soil particles. (wikipedia.org)
  • As a consequence water and air is displaced and soil bulk density increases, resulting in a reduced permeability for water and air. (wikipedia.org)
  • Soil water content, a high water content increases susceptibility to compaction as the layer of water on the surface of soil particles shields interactions between soil particles Initial bulk density, dense soils are more resistant to compaction as the number of particle interactions is higher. (wikipedia.org)
  • Organic matter content, increases resistance to compaction as organic matter acts as a buffer, binding minerals and water pH, affects net charges of molecules Soil compaction can occur naturally by the drying and wetting process called soil consolidation, Inflation pressure of wheels and tyres also plays an important role for the degree of soil compaction. (wikipedia.org)
  • pasture
  • 2010). Unweathered biochar impact on nitrous oxide emissions from a bovine-urine-amended pasture soil. (springer.com)
  • Susceptibility
  • Susceptibility of soil to compaction depends on several factors, which influence soil particle interactions: Soil texture, with fine textured soils (high clay content) being more susceptible to compaction than coarse textured soils. (wikipedia.org)
  • groundwater
  • The application of pig manure to a tillage soil can result in pollution of surface and groundwater bodies. (springer.com)
  • This process can cause on-site effects such as reduced crop growth, yield and quality as well as off-site effects such as increased surface water run-off, soil erosion, greenhouse gas emissions, eutrophication, reduced groundwater recharge and a loss of biodiversity. (wikipedia.org)
  • particles
  • The soil layer traps sediments, leaves and other particles, thereby treating the runoff before reaching an outlet. (lid-stormwater.net)
  • These filaments bind soil particles throughout the uppermost soil layers, forming a 3-D net-like structure that holds the soil together in a crust. (wikipedia.org)
  • Fungal hyphae can bind soil particles together. (wikipedia.org)
  • In healthy, well-structured soils, particles interact with each other forming soil aggregates. (wikipedia.org)
  • Water and air fills the voids between soil particles, where water interacts with soil particles forming a thin layer around them. (wikipedia.org)
  • This implies a reduction in soil volume by reducing the voids in between soil particles. (wikipedia.org)
  • manure
  • Three treatments were examined as follows: (a) non-amended soil (the study control), (b) soil mixed with biochar from the separated solid fraction of anaerobically digested pig manure, and (c) of soil mixed with biochar from Sitka Spruce. (springer.com)
  • Amendment with pig manure biochar increased the Morgan's P content of the soil, while leaching of P and C also increased, indicating the unsuitability of pig manure biochar as an amendment to soils which may be used as pig manure spreadlands. (springer.com)
  • The addition of wood-derived biochar to tillage soil which will receive pig manure may be justifiable, as it reduces nutrient leaching from the soil, sequesters C and may allow for higher application rates of pig manure. (springer.com)
  • vegetation
  • Invasion of a deciduous forest by earthworms: changes in soil chemistry, microflora, microarthropds, and vegetation. (wikipedia.org)
  • bacterial
  • We did not uncover any bacterial sequences that were closely related to known nitrifiers in either soil, but sequences related to archaeal nitrifiers were found in control soils. (wiley.com)
  • conventional
  • Aggregate-Protected and Unprotected Organic Matter Pools in Conventional- and No-Tillage Soils" (PDF). (wikipedia.org)
  • Together with soil erosion, it is regarded as the "costliest and most serious environmental problem caused by conventional agriculture. (wikipedia.org)
  • disturbance
  • Land use influences soil nitrogen cycling through its effects on fertilizer input, soil water, organic matter, pH and disturbance. (beslter.org)
  • Because soil methanotrophs may take longer to respond to alterations of N cycling than the 1/2 year treatment in this study, we also tested species richness-effects in two separate 5-year field studies, but results were ambiguous, indicating complex interactions with soil disturbance. (uzh.ch)
  • They are found throughout the world with varying species composition and cover depending on topography, soil characteristics, climate, plant community, microhabitats, and disturbance regimes. (wikipedia.org)
  • water
  • Green roofs, however, can help make nitrogen pollution less of a water quality problem. (lid-stormwater.net)
  • The water retention capacity of the soil is dependent upon both the properties of the soil substrate and the vegetative cover. (lid-stormwater.net)
  • This graph depicts changes in dissolved oxygen & E h of a soil following water-saturation. (coursehero.com)
  • Other research has shown evidence of bidirectional transport in soil-fungal-plant connections in redistributing water in arid ecosystems. (wikipedia.org)
  • Journal of Soil and Water Conservation 39: 158-161. (wikipedia.org)
  • Various agencies such as the Department of Health and others managed the soil and water aspects of environment. (wikipedia.org)
  • Environmental issues in Taiwan Executive Yuan Biotechnology Nitrogen cycle Soil science Water cycle Atmospheric sciences Numerical weather prediction National Space Organization Pollution Sewage treatment Demographics of Taiwan Water security Food security Show house Energy security History of Taiwan Economy of Taiwan 行政院環境保護署 (22 November 2011). (wikipedia.org)
  • chemistry
  • We used a variety of techniques to examine the effects of chronic N amendments on SOM chemistry and microbial community structure and function in an alpine tundra soil. (wiley.com)
  • He became an instructor in chemistry at the University of Nebraska, while working as an assistant chemist for the University's Experimental Station, specializing in soil chemistry. (wikipedia.org)
  • plants
  • Biennial plants are plants that takes only two seasons or 2 years to complete their life cycle. (reference.com)
  • The practical importance of this is the potent greenhouse gasses (ex: CH 4 ) and toxic gases to plants (ex: C 2 H 4 ) are formed under reducing conditions found in waterlogged soils. (coursehero.com)
  • These forms of N are organic nitrogen, which is unavailable to plants. (coursehero.com)
  • For example, extracellular enzymes present in the soil become active nearly instantaneously after any moisture pulse, while production in microbes and plants have lag times of various durations, and require pulse events of different sizes. (wikipedia.org)
  • Arid ecosystems also often have patchy distributions of vascular plants with bare patches of soil in between. (wikipedia.org)
  • This may reduce the concentration of inorganic N in soil and reduce the nitrogen available to plants growing in the soil. (wikipedia.org)
  • In addition, young plants may be unable to grow without the surface nitrogen source provided by the layer of detritus. (wikipedia.org)
  • This may cause nitrogen deficiency in plants growing in the soil. (wikipedia.org)
  • It is now known that there is a more complex cycling of amino acids between Rhizobia bacteroids and plants. (wikipedia.org)
  • mineral
  • Through non-linear plant-soil feedbacks triggered by harvest, strong N limitation promotes short periods of immobilization and mineral N retention, which alter the relation between MSY and N losses. (marquette.edu)
  • This mineral nitrogen is said to be immobilized. (wikipedia.org)
  • deficient
  • Only deficient N values were observed during fertilizer cycle 1 in 2008 from PCUMIX and BS. (ufl.edu)
  • Total Kjeldahk Nitrogen in tissue increased over the time with no N deficient ranges in any of the N sources. (ufl.edu)
  • fungal
  • The fungal loop hypothesis is similar in concept to the microbial loop hypotheses in oceans or soil, more specifically for arid ecosystems. (wikipedia.org)