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Fuktanalys av kallvind i ett befintligt lågenergihus med hjälp av WUFI och en praktisk fältstudie / Moisture analysis of a cold attic in a low energy house with the use of WUFI and a field studyTrandem, Kevin, Loberg, Karl January 2017 (has links)
Issues related to moisture are one of the most common problems buildings are exposed to. Moisture issues have a tendency to lead to damage and growth of unwanted microorganisms on the buildings structure. Buildings troubled of issues related to moisture may have a negative impact on the indoor environment, the health of the people living there and the abrasion resistance of the structure. According to a research published by Boverket in 2010, approximately 36 % of all buildings in Sweden suffers from damage and mold in relation with moisture, most troubled by these kind of issues are small houses. More specifically, the attic in small houses is the most troubled part. The cost of maintenance for the damage caused by moisture is estimated to 91,2 billion SEK. The origin of moisture issues can depend on several different factors. Weather and climate are of great meaning if a building will be exposed to moisture issues. Precipitation, air humidity, temperature, wind speed and wind direction are some contributing factors. Today, constructing energy-saving buildings is a hot topic and a consequence of the more strict regulations regarding energy consumption. The sector of construction and service stands for approximately 40 % of Swedens total consumption of energy. Due to the topic of houses with a low consumption of energy, new ideas have come forward through the years and a typical example is the concept: Low energy house. Low energy houses are projected as dense houses with a high amount of insulation included with purpose to minimize the loss of thermal energy. Debates regarding how low-energy house has an increased risk to exposure of moisture issues than traditional houses as a consequence to a more dense structure, is common. Theoretically, low-energy houses have an increased risk for exposure but it can be avoided depending on the layout of the house and knowledge of moisture issues. Cold attics constitute a room in the attic where the climate has a resemblance to the outdoor climate. Former studies show a trend that cold attics have an increased risk for exposure of mold growth as a consequence to moisture issues. A low-energy house with a cold attic should, according to what is stated above, make a great risk for exposure of moisture issues. In this study a moisture analysis is performed of a cold attic in a low-energy house. The house is located in Molkom, Värmland and is relatively new-built. The goal with the analyzation is to examine if parts of the cold attic has a risk to be exposed to mold due to moisture issues and with relation to weather factors. The analyze was performed using two separate methods: a field study where moisture-measuring equipment was attached to the roofs trusses inside the cold attic in order to measure moisture ratio in these, relative air humidity and temperature in the surroundings of the trusses. A weather station was set up in the closeness of the house in purpose to be able to compare weather data to the data recorded by the measuring equipment in the attic. The weather station measured temperature, relative air humidity, precipitation, wind speed and wind direction from the outdoor climate. The second method was based on performing a thermal and humidity simulation using WUFI. In the program a simulation of the cold attic was performed. The simulation presented moisture data during the same interval as the field study and for the further five years to come. Measured data from measuring equipment, weather station and WUFI was compiled in order to be analyzed using produced, critical values for mold growth. Factors of values which was used for performing the analysis and the final evaluation was following: Relative air humidity, temperature and moisture ratio in the wood of the roofs trusses. The study showed that the cold attic does not make a risk for being exposed to issues regarding mold growth thus reign of critical values during some of the periods of the interval. The outdoor climate indicated to have a controlling effect on the climate in the attic. The relative air humidity in the attic rises when precipitation occurs and also when powerful, southwestern and southern winds reigns. The relative air humidity in the attic increases substantially when precipitation occurs in combination with southern winds. As precipitation occurs in itself, the temperature drops in the attic. Temperature in the attic does not show any noticeable connection to wind direction or speed. The roof trusses moisture ratio increases during periods of precipitation and also when southern or northern winds reigns. Wind speed does not show any noticeable connection with how the moisture ratio differs. The relative air humidity in the cold attic has a close resemblance to the relative air humidity outside. The temperature in the cold attic has a close resemblance to the temperature outside. Moisture ratio in the roof trusses does not show any noticeable connection to relative air humidity and temperature outside. / Fuktproblem är bland de vanligaste problemen som ett hus kan utsättas för. Problem i form av fukt leder ofta till skador eller tillväxt av oönskade mikroorganismer i husets konstruktion. Hus som drabbats av problem i samband med fukt kan ha en negativ inverkan på inomhusmiljön och hälsan för de människor som vistas i husen samt försämra konstruktionens hållfasthet. Enligt en undersökning publicerad av Boverket år 2010 är cirka 36 % av alla byggnader i Sverige utsatta för fukt- och mögelskador, flest skador påvisas i småhus. I småhusen är takets vindsutrymme den mest utsatta delen. Åtgärdskostnaden för fuktskadorna i drabbade småhus uppskattas till en kostnad om 91,2 miljarder kronor. Uppkomsten av problemen beror på många olika faktorer. Väder och klimat är av stor betydelse för hur ett hus utsätts för oönskad fukt. Nederbörd, luftfuktighet, temperatur, vindhastighet och vindriktning är några faktorer som är bidragande. Idag finns ett stort fokus på att bygga energisnåla hus medfört av allt hårdare krav om energiförbrukning. Sektorn för bostäder och service står för upp till 40 % av Sveriges totala energianvändning. I frågan om mer energisnåla byggnationer har nya idéer växt fram under åren, och ett typiskt exempel är lågenergihus. Lågenergihus är projekterade som täta och välisolerade hus i syfte att minska husets svinn av värmeenergi och därmed minskad energiåtgång för att vara i drift. Det debatteras flitigt om lågenergihus löper större risk att drabbas av fuktproblem än traditionella hus på grund av konstruktionens täthet och större mängd värmeisolering. Teoretiskt sett löper lågenergihus en större risk för att drabbas av fuktproblem i form av mikrobiell tillväxt men beroende på utformning och med hjälp av kunskap kan problemen undvikas. Kallvindar utgör ett vindsutrymme där klimatet i utrymmet liknar klimatet utomhus. Tidigare studier visar en trend att kallvindar har en ökad risk att utsättas för mögelsvamp på grund av fuktproblem. Ett lågenergihus med kallvind bör, enligt ovanstående, utgöra en stor risk att drabbas av fuktproblem. I denna studie har en fuktanalys genomförts av en kallvind i ett lågenergihus. Huset är placerat i Molkom, Värmland, och är relativt nybyggt. Målet med analysen var att undersöka om delar i kallvinden löpte risk att drabbas av fuktproblem i form av påväxt av mikroorganismer i relation till vädrets faktorer. Analysen utgjorde två separata metoder: en praktisk mätstudie där fuktmätare fästs i takstolarna inom kallvinden för att mäta fukthalt i takstolarna samt relativ luftfuktighet och temperatur i dess omgivning. I husets närhet placerades en väderstation i syfte att jämföra väderdata med data från mätare placerade i vindsutrymmet och hur vädret påverkar klimatet i vindsutrymmet. Väderstationen gav data för temperatur, luftfuktighet, nederbörd, vindhastighet och vindriktning utomhus. Den andre metoden var att utföra en värme- och fuktsimulering i programmet WUFI. I programmet genomfördes en simulering av kallvinden. Simuleringen presenterade fuktdata under samma tid som den praktiska studien avsett samt under kommande 5 år. Uppmätt data från mätare, väderstation och WUFI sammanställdes för att analyseras utifrån framtagna kritiska värden för mikrobiell tillväxt. Värden för faktorer som beaktades för att genomföra analysen och den slutliga bedömningen var: relativ luftfuktighet, temperatur och fukthalt i material. Ur studien framgår det att kallvinden inte utgör någon risk att drabbas av problem i samband med mögelsvampstillväxt trots kritiska värden under vissa perioder. Vädret visade sig att ha en stor inverkan på klimatet i vindsutrymmet. Den relativa luftfuktigheten i vindsutrymmet ökar då nederbörd förekommer samt när kraftiga, sydvästliga och sydliga vindar råder. Den relativa luftfuktigheten i vindsutrymmet ökar väsentligt då nederbörd sker i kombination med sydliga vindar. Då nederbörd förekommer sjunker temperaturen i vindsutrymmet. Temperaturen i vindsutrymmet visar inga tydliga samband med vindens riktning eller hastighet Fukthalten i takstolsvirket i vindsutrymmet ökar under nederbördsperioder samt när sydliga eller nordliga vindar råder. Vindens hastighet visar ingen påverkan för fukthalten. Den relativa luftfuktigheten i vindsutrymmet liknar den relativa luftfuktigheten utomhus. Temperaturen i vindsutrymmet liknar den temperatur som råder utomhus. Fukthalten i takstolarnas virke förhåller sig inte tydligt i samband med relativ fuktighet och temperatur utomhus.
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Use of Water Indices Derived from Landsat OLI Imagery and GIS to Estimate the Hydrologic Connectivity of Wetlands in the Tualatin River National Wildlife RefugeBlackmore, Debra Sue 30 August 2016 (has links)
This study compared two remote sensing water indices: the Normalized Difference Water Index (NDWI) and the Modified NDWI (MNDWI). Both indices were calculated using publically-available data from the Landsat 8 Operational Land Imager (OLI). The research goal was to determine whether the indices are effective in locating open water and measuring surface soil moisture. To demonstrate the application of water indices, analysis was conducted for freshwater wetlands in the Tualatin River Basin in northwestern Oregon to estimate hydrologic connectivity and hydrological permanence between these wetlands and nearby water bodies. Remote sensing techniques have been used to study wetlands in recent decades; however, scientific studies have rarely addressed hydrologic connectivity and hydrologic permanence, in spite of the documented importance of these properties. Research steps were designed to be straightforward for easy repeatability: 1) locate sample sites, 2) predict wetness with water indices, 3) estimate wetness with soil samples from the field, 4) validate the index predictions against the soil samples from the field, and 5) in the demonstration step, estimate hydrologic connectivity and hydrological permanence. Results indicate that both indices predicted the presence of large, open water features with clarity; that dry conditions were predicted by MNDWI with more subtle differentiation; and that NDWI results seem more sensitive to sites with vegetation. Use of this low-cost method to discover patterns of surface moisture in the landscape could directly improve the ability to manage wetland environments.
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Mikrotalasni senzori vlažnosti zemljišta zasnovani na komponentama sa distribuiranim parametrima / Microwave soil moisture sensors based on distributed elementsKitić Goran 04 October 2016 (has links)
<p>Senzori vlažnosti zemljišta su od ključnog značaja za sisteme za navodnjavanje kojima je moguće uvećati prinose u proseku za 79%. U okviru ove disertacije razvijena su dva senzorska rešenja za merenje vlažnosti zemljišta. Prvi senzor je namenjen određivanju vlažnosti uzoraka zemljišta u neporemećenom stanju. Rešenje je nastalo nadogradnjom standardne opreme za uzorkovanje zemljišta. Za pomenuti senzor konstruisana je kalibraciona kriva kojom je moguće odrediti vlažnost zemljišta sa relativnom greškom ne većom od 2.5%. Drugo senzorsko rešenje je fabrikovano u LTCC tehnologiji, malih je dimenzija i namenjeno je primeni na terenu. Glavna prednost ovog senzora je da na njega ne utiče provodnost zemljišta koja je usko povezana sa tipom zemljišta. Predloženi senzor je testiran na dva uzorka zemljišta različitog hemijskog sastava. Rezultati merenja su pokazali da tip zemljišta nema uticaj na odziv senzora. Ostvarena relativna greška u odnosu na pun merni opseg iznosi 5.36%.</p> / <p>Soil moisture sensors are of great importance for the irrigation systems that<br />are able to increase the yiel on avarage of 79%. Within this thesis two sensor<br />solutions have been developed. The first sensor, which is intended for<br />laboratory use, has been designed by upgrading existing sampling<br />equipment. The constructed calibration curve for this type of sensor that can<br />be used for soil mositure determination with relative error not larger than<br />2.5% with respect to full scale output. The second sensor solution is<br />designed to be used in the field. It is fabricated in LTCC technology and it is<br />charaterized by small overall dimensions. The main advantage of this sensor<br />is that it is immune to the soil electrical conductivity which is closely related to<br />the soil type. Proposed sensor is tested on two soil sample of different<br />chemical composition and the results have shown that the type of soil does<br />not influence the sensor response. The relative error with the respect of full<br />scale output was only 5.36 %.</p>
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Influence of head-moisture treatment on functional, colour and thermal properties of bambara ground-nut starchMathobo, Vhulenda Melinda 20 September 2019 (has links)
MSCFST / Department of Science and Technology / Heat-moisture treatment (HMT) is a physical modification that alters the physicochemical
properties of starch without changing its molecular structure. The objective of the study was to
investigate the influence of HMT on the functional, colour and thermal properties of bambara
groundnut (BG) starch. A central composite rotatable design comprising two independent factors
(temperature and time) was used for the study. The central composite rotatable design was
generated using Design-Expert software version 8.0.1.0. Bambara starch extraction was done by
milling BG into flour (5 Kg), suspension in 15 L, 0.3% sodium hydroxide and centrifugation
followed by washing using distilled water. The starch was then HMT treated in an air oven at 80 -
120 °C for 30 - 90 min under 15 % moisture content (MC) (HMT 15), 25% MC (HMT 25) and 35%
MC (HMT 35). The highest L* and WI values for HMT treated BG starch were observed at HMT
80 °C for 30 min under 15% MC; 100 °C for 60 min (25% MC); and 100 °C for 17.57 min (35%
MC) while the lowest was observed in HMT 100 °C for 102.43 min (15% MC); 120 °C for 90 min
(25% MC); and 120 °C for 90 min (35% MC). In HMT 15-BG starch, the gelatinisation parameters
onset (To), peak (Tp) and concluding temperature (Tc) of the samples decreased as treatment time
and temperature increased whereas gelatinisation enthalpy of BG starch increased with increase
in HMT treatment temperature and time. In HMT 25-BG starch Tp, and gelatinisation enthalpy of
the starch increased with increase in HMT treatment temperature and time. While in HMT 35-BG
starch, To, Tp, Tc and gelatinisation enthalpy of the starches decreased with increase in HMT
treatment temperature and time. In HMT 15-BG starch, the water absorption capacity (WAC),
solubility and swelling power (SP) decreased as treatment time and temperature increased while
oil absorption capacity (OAC) of the starch increased with increase in HMT treatment temperature
and time. In terms of HMT 25-BG starch, the WAC and OAC increased as HMT treatment time
and temperature increased while SP and solubility of the starch decreased with increase in HMT
treatment temperature and time. In HMT 35-BG starch, OAC, solubility and SP decreased as
treatment time and temperature increased while WAC of the starch increased with increase in
HMT treatment temperature and time. The optimum HMT conditions for BG starch were found to
be 80 °C for 30 min (HMT 15), 105.74 °C for 30 min (HMT 25), and 113.16 °C for 30 min (HMT
35). Desirability of the obtained optimum conditions were 0.63 (HMT 15), 0.56 (HMT 25) and 0.64
(HMT 35). Information obtained from scanning electron micrograph indicates oval and round
shape for bambara starch granules, with varying sizes. The range of the granule size width was
4.2 – 4.7 mm and 10 μm for length. The modified starches showed some changes in granule
morphology as they seem to disintegrate with application of HMT. Unmodified and HMT - BG
starches showed characteristic FTIR bands linked with common starches. All the samples
displayed complex vibrations in the region below 1000 cm-1 due to the skeletal vibrations of the
glucose pyranose ring. Statistical analysis on colour, thermal and functional properties of HMT
15-BG, HMT 25-BG and HMT 35-BG starch showed that effects of temperature and treatment
time had no significant (p ≥ 0.05) effect on these properties of HMT-BG starch. However,
treatment time had a significant linear effect (p ≤ 0.05) on swelling power, for HMT 15-BG starch.
In HMT 35-BG starch, WAC was significantly affected by quadratic effect of temperature and time
while solubility was significantly affected by linear effect of time and quadratic effect of
temperature. / NRF
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TAKTERRASSER PÅ FLERBOSTADSHUS : En analys av takterrasser relaterat till dess projektering, utförande och fuktproblem de kan medföraLundqvist, Oscar January 2021 (has links)
Roof terraces are in great demand today and can add value to the home. Theirdesign can vary but often they can also contribute and increase the risk of moisture in the building and cause problems. This is because they are flat and often have doors that lead out to a terrace where water can collect. The purpose of the study is to examine how roof terraces are designed and executedwith a goal of finding designs that should be avoided and designs that can be recommended.This will be done by reviewing previously designed roof terrace projects, literature studies,interviews with people with significant experience in the subject and highlighting relevantexperiences from my previous professional experiences as a carpenter. In the study, critical areas and processes during the design as well as the production of a roofterrace will be highlighted and explained why they are critical. The advantages of asuperstructure consisting of a wooden deck will be highlighted. The importance of the rightskills at the right time will also be discussed. The results of the work will highlight the importance of a solid design of waterproofing layerson roof terraces and why implementation of waterproofing layers may be relevant. It will alsosummarize what you should think about in order to design blueprints that meet the right conditions for a high quality and improved execution. / Takterrasser på flerbostadshus är idag väldigt efterfrågat och kan ha ett stort mervärde till en bostad. De kan utformas varierat men gemensamt för dem att de bidrar till en ökad risk för fuktproblematik i byggnaden. Detta då de är nästintill platta och dessutom ofta har dörrar ut till terrassen i höjd med där vatten samlas.Studiens syfte är att granska hur takterrasser projekteras samt utförs av idag med ett mål om att finna utföranden som bör undvikas och utföranden som kan rekommenderas. Detta har gjorts genom granskning av tidigare utförda takterrassprojekt, litteraturstudier, intervju av personer med betydande erfarenhet i ämnet samt att lyfta fram relevanta erfarenheter från tidigare yrkeserfarenheter som stommontör/snickare.I arbetet granskas och förklaras kritiska byggnadstekniska detaljer och kritiska delar av projekteringen för takterrasser. Fördelarna med att en påbyggnad utgörs av en trall i trä belyses. Även vikten av rätt kompetenser vid rätt tillfälle diskuteras.Resultatet av arbetet belyser vikten av ett gediget utförande av tätskikt på takterrasser och varför en extra kontroll av tätskikt kan vara relevant. Det summerar även vad som bör beaktas för att projektera rätt förutsättningar till utförandet.
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Bioenergy from Swedish forests : A Study of extraction methods, quality and effects for forest ownersNilsson, Daniel January 2020 (has links)
The forest constitutes a very important element of renewable natural resources and makes a significant contribution to the Swedish bioeconomy. Biofuels are Sweden’s largest source of energy; of all the energy we use, 32% comes from biofuels, and of this approximately 85% comes from the forest and the forestry sector. In spite of this, logging residues constitute only a small component, compared to for example byproducts from sawmills and pulpindustry, and there is considered to be great potential for increasing their use. In 2019 the Swedish Forestry Agency issued new recommendations for logging residue harvest and ash recycling. This was a further development of the 2008 recommendations, which formed the foundation for how forest fuel producers work today, and were based on several decades of research into, for example, the impact on forest productivity and technological development of machinery. This practice of logging residue harvest aims to yield a dry and defoliated fuel where the needles are left at the clear felled area. However, if we are to increase the use of green renewable energy from forestry, it is very important to understand how different procurement systems affect the handling and storability of fuels from a quality perspective. It is also of great importance to understand, from the forest owners’ perspective, how removal of additional products from forestry influences nutritional balance and long-term productivity. If harvesting of logging residues does not affect long-term productivity, it is up to small-scale private forest owners to decide if removal of logging residues will be performed on their land. This thesis addresses some of these issues regarding removal of logging residues from the point of tree harvest up to the point of delivery to the energy conversion industry when the fuel chips are measured. Regarding different methods of handling of logging residues, the traditional method – dry-stacking – was compared with the, fresh-stacking method. The logging residues investigated came from stands that mainly consisted of Norway spruce (Picea abies (L.) Karst). The loads investigated in Paper 3 also came from logging of spruce-dominated forests. Both methods aim to dry the logging residues to an acceptable moisture content for delivery to the energyconversion industry. For the later part in the supply chain, moisture content measurements of logging residues were compared during a winter and summer season. The results of the studies indicate that the two methods do not create results that differ from what is allowed by the Swedish Forestry Agency and that they are quite similar with respect to dry mass- and nutrient removal from the clearfelled area. The results also show that similar yields and distributions of material are obtained from the logging residues with different stacking methods; in addition, the final felling itself, combined with the work performed by the forwarder operator, has a greater impact on the result than the method chosen for residue stacking of the logging residues. For the individual clear-felled area and the individual forest owner the increased removal associated with freshstacked logging residue has no major impact, however from a national perspective this small increase in removed logging residues may yield a supplement of between 0.5 – 1 TWh of green energy annually. Regardless of treatment, the studies indicated that the delivered fuel chips will have similar characteristics. The moisture content measurement techniques currently in use are sufficiently accurate and reliable. However, if the forest owner is unlucky and an error in measurement occurs or comminution and delivery happens during an especially wet period they may suffer a significant financial loss; indeed, it is generally not under the individual forest owners’ control when the logging residues are comminuted and delivered.
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Evaluation of moisture safety in cold attic and external wall designs commonly used in the building sectorSaleh, Yad January 2020 (has links)
Kontinuerligt försvårade och mer krävande energikrav utlyst från den Europeiska unionen ochsvenska myndigheter har lett till en förändring av hur konstruktionsdetaljer och lösningar somanvänds inom nyproduktionssektorn utformas. Förändringarna har skapat en osäkerhet ur enfuktsäkerhetssynpunkt. Uttökade krav och förbättrad energiprestanda låter som ett problemfrittideal att sträva efter, dock har det i många fall lett till oförutsägbara konsekvenser i olika delar avbyggnaden. Två av de byggnadskomponenter som påverkats har varit ytterväggar och kallvindarsom har varit utformade utefter nya energikrav i nyproducerade hus.Den största utmaningen med utformningen av nyare kallvindar har varit balansgången mellanhög energiprestanda genom ökad isoleringstjocklek och fuktsäkerhet. Ökad isoleringstjocklekkombinerat med minimerad värmeförlust från ventilationsaggregat, inomhus och skorstenar harlett till, i överlag, kallare vindutrymmen med ökad risk för kondensation av fukt på kallare ytor ijämförelse med äldre byggnader. En lösning på detta har varit inkluderingen av uteluftsventileringi utformningen av vinden. Detta har lett till en återkommande fråga angående den optimalaluftomsättningen som krävs för utökad fuktsäkerhet, och i vissa fall, om uteluftsventilering ensär nödvändig.En annan stor utmaning har varit att säkerhetsställa fuktsäkerheten i väggar som är isolerade ien högre grad. Det finns en potentiell risk för kondens i kalla, yttre ytor om isoleringen utökas.Utöver detta så existerar det en hel del lösningar som har fungerat i det förflutna men som lärleda till ökad risk för skada när det kombineras med nya utformade lösningar som uppfyllerenergikraven.Detta arbete har fördjupat sig i dessa två komponenter, ytterväggar och kallvindar, för atthitta kritiska designval som har en stor påverkan på fuktsäkerheten. Arbetet har skett medsimuleringsprogrammen IDA ICE och WUFI 6. Båda programmen har kombinerats för attuttnyttja deras styrkor i simuleringsprocessen.Resultatet visar att en låg luftomsättning är optimal. Ingen ventilering alls lär leda till ökadfukthalt och ökad luftomsättning lär leda till en betydligt högre risk för mögel på råsponten ivinden. Placeringen av ett litet isoleringslager ovanpå råsponten leder till en minskad risk förmögel.Ytterväggar med tjockare isolering är mer benägna att skadas i jämförelse med mindre isoleradeväggar. Dock är det visat att en uttökad isoleringstjocklek även kan vara till fördel för att minskamögelrisken om isoleringslagret som uttökas är det yttersta isoleringslagret. Ett annat krav är attdet yttersta lagret bör ha dränerande egenskaper, exempelvis mineralull. Beräkningarna har ävenpåvisat ett antal andra faktorer som påverkar fuktsäkerheten i dess helhet.
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EARLY ROOT AND SHOOT ELONGATION OF SELECTED WARM SEASON PERENNIAL GRASSES.Simanton, John Roger. January 1984 (has links)
No description available.
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Short term effects of annual ryegrass, red clover and hairy vetch cover crops on various indicators of soil healthStout, Breanna January 1900 (has links)
Master of Science / Department of Biological and Agricultural Engineering / Philip L. Barnes / The world’s population has passed 7 billion and is expected grow to more alarming numbers by the year 2050. The increase in human life on the planet ushers the need to responsibly and sustainably grow more food. In order to meet the demand necessary, it is crucial that soil remains healthy and crop yields continue to increase in efficiency. Irresponsible or ill-informed practices can lead to depleted resources and degradation of fertile soils that may limit a producers’ ability to sustainably grow food. Cover crops are a tool that can be used to address issues the modern producer may face. Cover crops have been shown to increase cash crop productivity, improve soil health by improving soil physical and chemical properties as well as providing protection from soil erosion runoff or nutrient leaching.
A study was conducted in 2014 to examine the short term effects associated with cover cropping systems. The effects of ryegrass, red clover and a cover crop cocktail (mixture of ryegrass, red clover and hairy vetch) compared to bare tilled and bare control plots were studied. The five treatments were replicated three times in a completely randomized study and analyzed. Soil physical health indicators such as bulk density and porosity were calculated. Soil and cover crop nutrient use, as well as, soil moisture content data was collected and analyzed using excel and ANOVA statistical procedures.
In the short term, the study found that there was only statistically significant differences between cover cropping regimens, tilled and control plots in regards to biomass production and biomass nutrient concentrations (α=0.05). The cocktail mix provided more biomass, N and P than the ryegrass and clover plots alone. Observable differences in cover crop volumetric soil moisture and water used between plots demonstrated that cover crops utilize soil moisture in the short term, which must be considered in areas experiencing water stress. Although more long-term data is needed to truly quantify how cover crops effect various aspects of soil health, this study demonstrated how cover crops have the potential for providing numerous benefits such as increased erosion control, lower reliance on anthropogenically created nutrients and the reduction of weeds. Overall the benefits associated with cover crops are still being researched and while adoption of cover cropping systems has been slow, a push towards agricultural sustainability while increasing food production will increase the amount of producers utilizing cover crops in the coming years.
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Interrelations of temperature and soil moisture in the growth of young wheat plantsChang, Hsien Tsiu January 2011 (has links)
Typescript. / Digitized by Kansas State University Libraries
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