| 1. |
- Bergkvist, Lisa, et al.
(författare)
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Carbon Sequestration Potential f Agroforestry Systems For Phytoremediation In Chinandega, Nicaragua
- 2018
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Ingår i: Linnaeus Eco-Tech 2018. ; , s. 211-211
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Greenhouse gases in the atmosphere have increased to earlier unrecorded levels, causing global climate change that increases GMT and threaten ecosystems and livelihoods. IPCC report suggest that agroforestry offers considerable carbon sequestration (c seq.) potential, especially for developing countries. The purpose of this study is to estimate the c seq. potential in different agroforestry systems suitable in Chinandega, Nicaragua - a deforested region where the ground is polluted by toxaphene and other POP:s. Three scenarios where studied; Shading system using Tectona grandis and Pogostemon cablin; Alley cropping using Erythrina poeppigiana and Ricinus communis and Silvopasture using Cordia alliodora and Brachiaria ruziziensis, the last scenario being divided into two subscenarios; unmanaged (grazed) and managed (harvested) grass. Calculations were performed using the modelling program CO2FIX v. 3.2, with a runtime of 100 years and assuming deforested area with no previous land use. Results show a significantly higher c seq. potential in Shading system (168/217 MgC/ha). Alley cropping yields 71 MgC/ha and Silvopasture results in 80/84 MgC/ha unmanaged and 65/70 MgC/ha managed. The higher number includes products from harvest. All scenarios show fluctuations over time due to thinning and harvesting practices. Phytoremediation potential of POPs has been shown in Ricinus communis and grass species. Soil c seq. is especially important to consider in longterm scenarios as this c seq. can be sustained over longer time. The inclusion of crop residue, the effect of grazing animals or changes in density of trees and crops and environmental fate of the toxic compounds need further assessment before considering large scale applications. Agroforestry practices could contribute to several benefits, including climate change mitigation and phytoremediation.
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| 2. |
- Akambih Tajam, Joseph, et al.
(författare)
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SMALL SCALE IN-SITU BIOREMEDIATIONOF DIESEL CONTAMINATED SOIL –SCREENING LIFE CYCLE ASSESSMENT OF ENVIRONMENTAL PERFORMANCE
- 2010
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Ingår i: ECO-TECH´10, 22-24 November 2010, Kalmar, Sweden. ; , s. 827-835
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Spillage of diesel oil and other petroleum products is a commonly creating need for siteremediation of contaminated soils. In Sweden the most common remediation action isexcavation of the contaminated soil and off site biological treatment by composting.However, a number of small sites spread out in rural areas end up low on priority lists, andwill not be attended to within foreseeable future if ever. For such areas a low cost, easy toapply remediation techniques would be of interest. Enhanced bioremediation of dieselcontaminants in soil by whey addition has been demonstrated in lab scale. Whey is a byproductfrom cheese production. A first pilot remediation trial on an actual site in Gäddede,County of Jämtland, was started the summer of 2010. Using this site as a case study ascreening life cycle assessment model has been set up. The goal of the study was toinvestigate the environmental performance of the whey method, to benchmark the wheymethod toward the excavation and composting practice and to identify environmental hotspots in the whey treatment life cycle. The study aims at establishing if further work shouldbe put into developing the method, or if the environmental performance is such that the wheymethod should be abandoned. It should be noted that even with a slightly worseenvironmental performance compared to other remediation alternatives whey treatment couldstill be of interest, since the small scale sites in rural areas we talk about here otherwise mostoften would not be attended to.Results from the screening life cycle assessment indicate a rather good environmentalperformance of the whey method, partly depending on impact category considered. For thewhey method, impacts from farming activities in the milk production chain allocated to thewhey give significant contributions. Transportation gives important impacts from both thewhey method and the excavation and off site composting, thus logistics should always beconsidered and optimized. The whey on-site treatment could be an interesting alternative forbioremediation especially at sites that would not otherwise be treated, due to small size orremote location.
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| 3. |
- Berg, S., et al.
(författare)
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Analysis of airborne organic lead
- 1984
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Ingår i: Biological effects of organolead compounds. - Boca Raton, FL : CRC Press. - 0849353092 ; , s. 278-
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 4. |
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| 5. |
- Dahlberg, Anders, et al.
(författare)
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Vedlevande arters ekologi : kunskaper för skötsel av död ved
- 2005
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Ingår i: Död ved i levande skogar. - Stockholm : Naturvårdsverket. - 9162054139 ; , s. 110-
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Betydelsen av död ved i skogen för biologisk mångfald är väl dokumenterad. Sveriges riksdag har fastställt 15 miljömål och varje mål är uppdelat i flera delmål. I ett av dessa mål, Levande skogar, konstateras att kvantiteten av hård död ved måste öka med åtminstone 40 procent i hela landet och betydligt mer i områden, där biologisk mångfald är speciellt hotad. Men än så länge finns inget detaljerat långsiktigt mål. Syftet med den här studien var att undersöka: 1. Vilken kvalitet och kvantitet av död ved behövs i skogen för att bevara mångfalden? 2. Var i landskapet är det viktigast att öka mängden död ved? 3. Hur når vi målet? Arbetet har baserats på litteraturöversikter och frågeformulär till markägare, avverkningsentreprenörer och tjänstemän inom skogsnäringen. Olika scenarier baserade på litteraturgranskningen framställdes via datorsimulationer, där mängden och spridningen av död ved varierade med en beräknad ökningstakt. Utifrån dessa studier kan vi dra följande slutsatser: 1. Somliga arter är specialiserade och kräver ett rikligt utbud av död ved (50 m3/ha eller mer). Dessa arter kan endast bevaras i skyddade områden. 2. Brukade skogar utanför skyddade områden med 20 m3 död ved/ha tycks vara högkvalitativa habitat för många arter. 3. I områden dominerade av skog bör sådana habitat täcka mellan 10 och 30 procent av landskapet. 4. Dessa områden bör lokaliseras i anslutning till skyddade områden och områden med sällsynta arter. 5. Om den här strategin antas, kommer medelvärdet för hela Sverige vara 10 m3 död ved/ha. 6. För att kunna nå det målet 2030 måste mängden död ved öka med 40 procent varje årtionde (vilket innebär en exponentiell ökning). 7. Men ännu viktigare än att nå ett visst medelvärde för hela Sverige är, att så snabbt som möjligt öka förekomsten av död ved i anslutning till områden med hotade arter. 8. Det gäller att så snabbt som möjligt identifiera dessa hotade områden/ biotoper och för det ändamålet behöver regionala bristanalyser tas fram. 9. Men död ved behövs även utanför speciellt rika områden, som en resurs för kommande generationer samt som spridningskorridor mellan olika “hot-spots”. Där kan mängden död ved vara mindre och ökningsgraden lägre. 10. Förutom ökningen av död ved är det viktigt med en större variation av olika kvaliteter samt en kontinuerlig tillförsel. 11. Att öka mängden död ved snabbt i hotade områden (hot-spots) enbart med hjälp av frivilliga åtgärder, kommer troligen att bli svårt. Därför kan olika nya slags politiska åtgärder vara nödvändiga (såsom ekonomisk kompensation). 12. För att definiera målet mer i detalj, behövs mer kunskap om den kritiska tröskeln, spridningsmöjligheter, habitat och substratanspråk samt populationsbiologi för några arter.
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| 6. |
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| 7. |
- Dupaul, Gabriel, et al.
(författare)
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Fiberbanks as substrate and feedstock for biological remediation : A practical analytical method development for organic pollutants analysis
- 2020
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Ingår i: Book of Abstracts. - : ABA Publishing. - 9789189081031
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Konferensbidrag (refereegranskat)abstract
- Fiberbanksfrom the pulp and paper industry are typically contaminated with a wide range ofchlorinated aromatic and aliphatic toxins such as HCB and other chlorinated benzenes, PCB,HCH, DDT, PCDD, PCDF and Chlorophenols. This poses a formidable challenge for theanalyst to develop appropriate analytical methodology for the monitoring of the progress ofremediation.In preparation to this undertaking, an examination of a practical analytical method using oneextraction method, one clean-up and one analysis method for the aforementioned targetcompounds found in the fibrous sediment. This method was performed using acceleratedsolvent extraction (ASE), a modified silica gel column and GC-FID/ECD. Additionally,an assessment of the levels of organic pollutants was conducted,with the purposeofmeasuringthe potential alteration in contaminantswhenfreeze-drying, air-drying andautoclavingpretreatments are applied to the sediment samples, prior to be used as a media forbiological remediation.The results showed that the ASE is a very fast and reliable method of extraction, with yieldscomparableorhigher than the reference Soxhlet extraction method. Theactivatedsilica gelcolumn demonstrated adequate purification of the sediment extract for analysisusingthe twodetectors, FID and ECD, whichwere able to identify the target analytes fromonlyone purifiedextract. The method employed in this study has the potentialto reduceboth processing timeand materialusedfor analytical sample preparation. Lastly, some modifications inconcentrations anddistribution of target analyteswere revealedin thesediments pre-treated byautoclave and air-driedwhencompared withthefreeze-dried sediments, which can helpunderstanding the development of the biological remediation process.
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| 8. |
- Ekström, Magnus, 1966-, et al.
(författare)
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Estimating density from presence/absence data in clustered populations
- 2020
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Ingår i: Methods in Ecology and Evolution. - : John Wiley & Sons. - 2041-210X. ; 11:3, s. 390-402
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Tidskriftsartikel (refereegranskat)abstract
- Inventories of plant populations are fundamental in ecological research and monitoring, but such surveys are often prone to field assessment errors. Presence/absence (P/A) sampling may have advantages over plant cover assessments for reducing such errors. However, the linking between P/A data and plant density depends on model assumptions for plant spatial distributions. Previous studies have shown, for example, how that plant density can be estimated under Poisson model assumptions on the plant locations. In this study, new methods are developed and evaluated for linking P/A data with plant density assuming that plants occur in clustered spatial patterns. New theory was derived for estimating plant density under Neyman-Scott-type cluster models such as the Matern and Thomas cluster processes. Suggested estimators, corresponding confidence intervals and a proposed goodness-of-fit test were evaluated in a Monte Carlo simulation study assuming a Matern cluster process. Furthermore, the estimators were applied to plant data from environmental monitoring in Sweden to demonstrate their empirical application. The simulation study showed that our methods work well for large enough sample sizes. The judgment of what is' large enough' is often difficult, but simulations indicate that a sample size is large enough when the sampling distributions of the parameter estimators are symmetric or mildly skewed. Bootstrap may be used to check whether this is true. The empirical results suggest that the derived methodology may be useful for estimating density of plants such as Leucanthemum vulgare and Scorzonera humilis. By developing estimators of plant density from P/A data under realistic model assumptions about plants' spatial distributions, P/A sampling will become a more useful tool for inventories of plant populations. Our new theory is an important step in this direction.
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| 9. |
- Ekström, Magnus, et al.
(författare)
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Logistic regression for clustered data from environmental monitoring programs
- 2018
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Ingår i: Ecological Informatics. - : Elsevier. - 1574-9541 .- 1878-0512. ; 43, s. 165-173
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Tidskriftsartikel (refereegranskat)abstract
- Large-scale surveys, such as national forest inventories and vegetation monitoring programs, usually have complex sampling designs that include geographical stratification and units organized in clusters. When models are developed using data from such programs, a key question is whether or not to utilize design information when analyzing the relationship between a response variable and a set of covariates. Standard statistical regression methods often fail to account for complex sampling designs, which may lead to severely biased estimators of model coefficients. Furthermore, ignoring that data are spatially correlated within clusters may underestimate the standard errors of regression coefficient estimates, with a risk for drawing wrong conclusions. We first review general approaches that account for complex sampling designs, e.g. methods using probability weighting, and stress the need to explore the effects of the sampling design when applying logistic regression models. We then use Monte Carlo simulation to compare the performance of the standard logistic regression model with two approaches to model correlated binary responses, i.e. cluster-specific and population-averaged logistic regression models. As an example, we analyze the occurrence of epiphytic hair lichens in the genus Bryoria; an indicator of forest ecosystem integrity. Based on data from the National Forest Inventory (NFI) for the period 1993-2014 we generated a data set on hair lichen occurrence on > 100,000 Picea abies trees distributed throughout Sweden. The NFI data included ten covariates representing forest structure and climate variables potentially affecting lichen occurrence. Our analyses show the importance of taking complex sampling designs and correlated binary responses into account in logistic regression modeling to avoid the risk of obtaining notably biased parameter estimators and standard errors, and erroneous interpretations about factors affecting e.g. hair lichen occurrence. We recommend comparisons of unweighted and weighted logistic regression analyses as an essential step in development of models based on data from large-scale surveys.
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| 10. |
- Esseen, Per-Anders, et al.
(författare)
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Broad-scale distribution of epiphytic hair lichens correlates more with climate and nitrogen deposition than with forest structure
- 2016
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Ingår i: Canadian Journal of Forest Research. - : Canadian Science Publishing. - 0045-5067 .- 1208-6037. ; 46:11, s. 1348-1358
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Tidskriftsartikel (refereegranskat)abstract
- Hair lichens are strongly influenced by forest structure at local scales, but their broad-scale distributions are less understood. We compared the occurrence and length of Alectoria sarmentosa (Ach.) Ach., Bryoria spp., and Usnea spp. in the lower canopy of > 5000 Picea abies (L.) Karst. trees within the National Forest Inventory across all productive forest in Sweden. We used logistic regression to analyse how climate, nitrogen deposition, and forest variables influence lichen occurrence. Distributions overlapped, but the distribution of Bryoria was more northern and that of Usnea was more southern, with Alectoria's distribution being intermediate. Lichen length increased towards northern regions, indicating better conditions for biomass accumulation. Logistic regression models had the highest pseudo R2 value for Bryoria, followed by Alectoria. Temperature and nitrogen deposition had higher explanatory power than precipitation and forest variables. Multiple logistic regressions suggest that lichen genera respond differently to increases in several variables. Warmingdecreased the odds for Bryoria occurrence at all temperatures. Corresponding odds for Alectoria and Usnea decreased in warmer climates, but in colder climates, they increased. Nitrogen addition decreased the odds for Alectoria and Usnea occurrence under high deposition, but under low deposition, the odds increased. Our analyses suggest major shifts in the broad-scale distribution of hair lichens with changes in climate, nitrogen deposition, and forest management.
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