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1
Mehmood, Khalid [Verfasser]. "Environmental behavior of cesium and strontium in agricultural and forest soil / Khalid Mehmood." Bonn : Universitäts- und Landesbibliothek Bonn, 2018. http://d-nb.info/1150851902/34.
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Goss, Charles W. "Influence of forest fragments on headwater stream ecosystems in agricultural landscapes." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1387536064.
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Willems, Nancy. "Forest structure and regeneration dynamics of podocarp/hardwood forest fragments, Banks Peninsula, New Zealand." Lincoln University, 1999. http://hdl.handle.net/10182/1301.
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Although species maintenance in small forest fragments relies on successful regeneration and recruitment, few studies have examined the effects of fragmentation on regeneration processes. New Zealand's podocarp species rely on large disturbance openings operating across a vegetated landscape to stimulate regeneration. Clearance of vegetation that results in small fragments of forest removes regeneration opportunities for podocarps by destroying the intact vegetation mosaic, and as a result may exclude disturbances of the scale necessary for podocarp regeneration. Fragmentation alters the disturbance regime of the landscape, with important implications for the regeneration of podocarps on Banks Peninsula. The four remaining lowland podocarp-hardwood fragments on Banks Peninsula were sampled to determine the structure and regeneration patterns of podocarps and to assess their long term viability. Density, basal area, and size and age class distributions were used to examine current composition, and in conjunction with spatial analysis, to identify past regeneration patterns and infer likely future changes in composition and population structure. Podocarp size and age class structures for three of the four fragments were characteristically even-sized and relatively even-aged (eg; Prumnopitys taxifolia c. 350 to 600 years), with little or no regeneration for approximately the last 200 years (old-growth fragments). Regeneration of the current podocarp canopy in the old-growth fragments may have been stimulated by flooding. The fourth younger fragment showed much more recent regeneration with Prumnopitys taxifolia, Podocarpus totara and Dacrycarpus dacrydioides mostly 80-160 years old, and substantial populations of seedlings and saplings, probably as a result of anthropogenic fire. In the absence of major disturbance the podocarp component in forest fragments on Banks Peninsula is likely to decline with composition shifting towards dominance by hardwood species. There is some evidence to suggest that canopy collapse will stimulate some podocarp regeneration within the fragments, however it appears to be unlikely that podocarps will persist on Banks Peninsula indefinitely within the fragments studied. There is an urgent need for more quantitative research in New Zealand fragmentation literature, and a need for more emphasis on processes. Banks Peninsula offers potential for a more landscape scale approach in forest management, and the maintenance of regenerating scrub in pockets about the Peninsula may offer the regeneration opportunities for podocarps that are lacking within protected fragments. My study took a quantitative approach in examining the effects of forest fragmentation on the demographics of podocarps and compositional change in forest fragments on Banks Peninsula.
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Bondoumbou, Pierre Vincent. "A critical evaluation of the tropical forest industry in the Republic of Congo as it conforms to the International Tropical Timber Organization sustainable management objectives." Thesis, The University of Arizona, 1999. http://hdl.handle.net/10150/291591.
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One of the innovations in the management of forest resources in the 1990s is the use of criteria and indicators (C&I) as a tool to measure the sustainability of forest management practices in general, as well as, specific forest related activities such as timber industry. The International Tropical Timber Organization has developed a set of criteria and indicators for the measurement of sustainability in natural tropical forests. This study uses these criteria and indicators to critically evaluate the current status of the forest industry in the Republic of Congo as it conforms to the ITTO sustainable management objectives. The study identifies both the progress made to achieve the ITTO "objective 2000", and weaknesses that need to be addressed in order to reach an overall sustainable forest industry. Recommendations are made to correct the identified weaknesses.
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Almond, Peter C. "Soils and geomorphology of a lowland rimu forest managed for sustainable timber production." Lincoln University, 1997. http://hdl.handle.net/10182/1782.
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Saltwater Forest is a Dacrydium cupressinum-dominated lowland forest covering 9000 ha in south Westland, South Island, New Zealand. Four thousand hectares is managed for sustainable production of indigenous timber. The aim of this study was to provide an integrated analysis of soils, soil-landform relationships, and soil-vegetation relationships at broad and detailed scales. The broad scale understandings provide a framework in which existing or future studies can be placed and the detailed studies elucidate sources of soil and forest variability. Glacial landforms dominate. They include late Pleistocene lateral, terminal and ablation moraines, and outwash aggradation and degradation terraces. Deposits and landforms from six glacial advances have been recognised ranging from latest Last (Otira) Glaciation to Penultimate (Waimea) Glaciation. The absolute ages of landforms were established by analysis of the thickness and soil stratigraphy of loess coverbeds, augmented with radiocarbon dating and phytolith and pollen analysis. In the prevailing high rainfall of Westland soil formation is rapid. The rate of loess accretion in Saltwater Forest (ca. 30 mm ka⁻¹) has been low enough that soil formation and loess accretion took place contemporaneously. Soils formed in this manner are known as upbuilding soils. The significant difference between upbuilding pedogenesis and pedogenesis in a topdown sense into an existing sediment body is that each subsoil increment of an upbuilding soil has experienced processes of all horizons above. In Saltwater Forest subsoils of upbuilding soils are strongly altered because they have experienced the extremely acid environment of the soil surface at some earlier time. Some soil chronosequence studies in Westland have included upbuilding soils formed in loess as the older members of the sequence. Rates and types of processes inferred from these soils should be reviewed because upbuilding is a different pedogenic pathway to topdown pedogenesis. Landform age and morphology were used as a primary stratification for a study of the soil pattern and nature of soil variability in the 4000 ha production area of Saltwater Forest. The age of landforms (> 14 ka) and rapid soil formation mean that soils are uniformly strongly weathered and leached. Soils include Humic Organic Soils, Perch-gley Podzols, Acid Gley Soils, Allophanic Brown Soils, and Orthic or Pan Podzols. The major influence on the nature of soils is site hydrology which is determined by macroscale features of landforms (slope, relief, drainage density), mesoscale effects related to position on landforms, and microscale influences determined by microtopography and individual tree effects. Much of the soil variability arises at microscales so that it is not possible to map areas of uniform soils at practical map scales. The distribution of soil variability across spatial scales, in relation to the intensity of forest management, dictates that it is most appropriate to map soil complexes with boundaries coinciding with landforms. Disturbance of canopy trees is an important agent in forest dynamics. The frequency of forest disturbance in the production area of Saltwater Forest varies in a systematic way among landforms in accord with changes in abundance of different soils. The frequency of forest turnover is highest on landforms with the greatest abundance of extremely poorly-drained Organic Soils. As the abundance of better-drained soils increases the frequency of forest turnover declines. Changes in turnover frequency are reflected in the mean size and density of canopy trees (Dacrydium cupressinum) among landforms. Terrace and ablation moraine landforms with the greatest abundance of extremely poorly-drained soils have on average the smallest trees growing most densely. The steep lateral moraines, characterised by well drained soils, have fewer, larger trees. The changes manifested at the landform scale are an integration of processes operating over much shorter range as a result of short-range soil variability. The systematic changes in forest structure and turnover frequency among landforms and soils have important implications for sustainable forest management.
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Zabala, Aiora. "Motivations and incentives for pro-environmental behaviour : the case of silvopasture adoption in the tropical forest frontier." Thesis, University of Cambridge, 2015. https://www.repository.cam.ac.uk/handle/1810/253009.
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On the frontier of biodiversity-rich tropical forests, how land is used has an important role in buffering the primary ecosystem. Unsustainable small-scale cattle farming endangers soil quality and degrades the landscape. Silvopasture is a type of agroforestry that provides both ecological and livelihood benefits. A number of projects have been implemented across the tropics to encourage silvopasture adoption, with varying success. This dissertation questions the reasons for variable outcomes among participants within these projects: what motivates smallholders to adopt innovative land-use practices, and what form of incentives may help to overcome obstacles and catalyse adoption. This dissertation contributes to the ongoing debate on payments for ecosystem services, specifically about their suitability and effectiveness. To understand what influences decisions to adopt sustainable land-use practices, I review systematically and quantitatively the literature on adoption predictors, and I empirically analyse participation and short-term adoption in a pilot project for planting fodder trees in the border of a protected forest in Chiapas, Mexico, using primary and secondary data. I focus on subjective perspectives and livelihood strategies of actual and potential participants as explanatory variables, which have received unduly scarce attention in past studies. This lack of attention is partially caused by the difficulties of operationalising internal variables. I address this challenge by developing an analytical approach that increases the precision of the resulting perspectives in Q methodology. I cluster livelihood strategies and model adoption. This in-depth case-study suggests the type of incentives that are adequate to encourage adoption of sustainable land-use practices. Results indicate that payments may not be the best incentive for pioneer adopters, and that the adoption process is composed of separate individual steps, which are influenced distinctly by identifiable predictors, such as livelihood diversity. Uncovering this heterogeneity of motivations towards adoption provides useful knowledge for designing more effective external policy interventions.
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Kim, Sei Jin. "Three Essays on the Implications of Environmental Policy on Nutrient Outputs in Agricultural Watersheds and the Heterogeneous Global Timber Model with Uncertainty Analysis." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1439601683.
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Sasnauskaitė, Vita. "Miško žėlimo ypatumai neapaugusioje mišku žemėje." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2009. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2009~D_20090615_114234-36850.
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Magistro darbe tiriamas miško žėlimas neapaugusioje mišku žemėje, vertinami įvairūs veiksniai įtakojantys savaiminį miško formavimąsi. Darbo objektas: 8 želvietės neapaugusioje mišku nedirbamoje žemėje. Darbo tikslas: įvertinti miško žėlimą ir jį įtakojančius veiksnius buvusioje žemės ūkio paskirties neapaugusioje mišku žemėje. Tyrimo metodai: aštuoniose žėlimo plotuose buvo išskirtos laikinos stačiakampės apskaitos aikštelės 10 m2 (2 x 5 m). Jose buvo nustatoma savaiminukų rūšis, skaičius, amžius, aukštis bei pažeidimai. Gautų duomenų apdorojimui, t.y. grafiniam duomenų pavaizdavimui, buvo naudojama Microsoft Excel programa. Darbo rezultatai: apibendrinus gautus duomenis nustatyta, kad visose tirtose želvietėse, rastas savaiminukų kiekis pakankamas naujam miškui formuotis. Nustatyta, kad dviejuose sklypuose tikslinės rūšys neatitiko norminių dydžių. Geriausios sąlygos miškui atsikurti P vyraujančių vėjų kryptis bei iki 60 m atstumas nuo miško pakraščio.This master work analyzing forestry natural regeneration in abandoned agricultural land, evaluation various subjects that influence to natural regeneration. Object of the work: 8 natural regeneration areas to abandoned agricultural land. Aim of the work: investigate natural forest regeneration process on abandoned agricultural land in district of Švenčionys. Methods: the research was accomplished in eight natural regeneration areas in forest stewardship of Švenčionėliai. There were chosen 63 research bars depending of forest area (every at 10 m2) at research time in this places. Results: the results of this investigation showed that birch and pine seeds are enough for itself forest sprouting in all research bars. The seeds were found from twenty to one hundred forty eight meters from the forest edge. The best conditions to forest`s sprouts grow is south directions and by 60 meters edge of a wood.
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Lindell, Lina. "Environmental Effects of Agricultural Expansion in the Upper Amazon : A study of river basin geochemistry and hydrochemistry, and farmers' perceptions." Doctoral thesis, Linnéuniversitetet, Institutionen för naturvetenskap, NV, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-14713.
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In this thesis natural science is combined with environmental psychology in order to determine how deforestation and subsequent agricultural expansion in the Peruvian highland jungle has affected the natural environment and rural livelihoods. This region is part of one of the most biodiverse areas on Earth and is also exposed to high pressure from deforestation that threatens the ecosystems as well as the well-being of local populations. The problem stretches beyond the upper Amazon since the region constitutes headwaters to theAmazon Riverand is part of the most important forest ecosystem of the world. This study evaluates the relative controls of human induced land-cover change and natural factors on the chemical status of soils, stream waters, and sediments, mainly through a spatial sampling design. The field work was located to two adjacent river basins underlain by sedimentary rocks. Streams of 48 independent sub-basins, the two main rivers, 80 upland soil sites (weakly developed soils on sandstone and siltstone) and four vertical profiles of floodplain sediments were sampled and analysed for major and trace elements, including nutrients and potentially toxic metals. Further, perceptions of environmental changes were investigated through a combination of quantitative and qualitative interview data collected from 51 smallholder farmers. Soils of primary forests were found to be chemically similar to those of regenerated forests and agricultural land-covers (pastures and coffee plantations), and differences in chemical concentrations between streams draining areas to varying degrees covered by forest were assigned to natural variability. In addition, the chemical composition of alluvial deposits was similar in the two drainage basins despite a substantial difference in exploitation degree (30 % versus 70 % cleared from forest). Thus, no evidence was found of long-term changes in the geochemistry of the Subandean river basins as a result of the conversion of primary forest to agricultural land-uses. The farmers, however, perceived an overall increase in environmental degradation as well as a change towards drier and warmer climatic conditions. The climate change was reported to be the main factor responsible for a negative trend in life quality (rural livelihoods). The results may be used in the work of identifying priorities and key factors necessary for environmental and socioeconomic sustainability in the upper Amazon.En esta tesis se combina la ciencia natural con la psicología ambiental con el fin de determinar como la ampliación de la frontera agrícola ha afectado el medio ambiente y los medios de vida en la selva alta del Perú. Esta región forma parte de una de las zonas con mayor biodiversidad en el planeta y a su vez está expuesta a una alta presión de la deforestación que amenaza a los ecosistemas, así como el bienestar de la población en esta zona. Así mismo, este problema se hace sentir mas allá de la selva alta ya que esta zona forma parte de las cabeceras del río Amazonas y pertenece al ecosistema forestal más importante del mundo. Este estudio evalúa los efectos de la agricultura de tala y quema, en comparación con los factores naturales, sobre las propiedades químicas de los suelos, las quebradas, y los sedimentos, principalmente a través de un diseño de muestreo espacial. El trabajo de campo se realizó en dos cuencas fluviales adyacentes que están compuestas por rocas sedimentarias. Quebradas de 48 sub-cuencas independientes, dos ríos principales, 80 localidades de suelo (poco desarrollados sobre areniscas y limolitas) y cuatro perfiles verticales de sedimentos fluviales fueron muestreados y analizados para los elementos mayores y menores, incluyendo nutrientes y metales potencialmente tóxicos. También se han investigado las percepciones sobre los cambios ambientales usando una combinación de datos cuantitativos y cualitativos, recopilados a través de entrevistas a 51 agricultores. Según los resultados no hubo diferencias significativas entre la química de suelos de bosques primarios y tierras agrícolas (pastos, plantaciones de café y de bosques secundarios). En cuanto a las quebradas, las diferencias en las concentraciones de sustancias químicas entre sub-cuencas afectadas por la deforestación en diferentes grados fueron asignados a una variabilidad natural. Además, la composición química de los depósitos aluviales fue similar en las dos cuencas a pesar de una diferencia sustancial en el grado de explotación (30 % en comparación con 70 % deforestado). Por lo tanto, no se encontró evidencia de cambios persistentes en la geoquímica de las cuencas Subandinas como resultado de la conversión de bosques a tierras agrícolas. Sin embargo los agricultores percibieron una tendencia general de aumento de la degradación del medio ambiente, así como un cambio en el clima a condiciones más secas y cálidas, lo cual fue reportado como el principal factor responsable de un cambio negativo en la calidad de vida. Estos resultados pueden ser utilizados en el trabajo de identificación de prioridades y factores claves para la sostenibilidad ambiental y socioeconómica en la selva alta.
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Lloyd, Davidson A. "The effect of forest to pasture conversion on soil biological diversity and function." Diss., Lincoln University, 2008. http://hdl.handle.net/10182/711.
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Recent declines in returns from primary forest products in New Zealand and projected increases in world food prices have led to the land-use conversion from plantation forest to pastoral farming in many lowland areas. After decades of forest cover the soils are in many cases less than adequate for pastoral farming, as they are acidic, with toxic levels of exchangeable aluminum, and contain low levels of available nitrogen (N), very high carbon (C):N ratio, and are devoid of earthworms and structural integrity. Overcoming the major site limitations of low soil pH and available N was a major priority and a field experiment was established in April 2005 to determine the impact of various rates of lime and N in relation to pasture establishment and production. Concerns about the short and long-term effects of these inputs on biological soil quality gave rise to the present study. The effects of land-use change and establishment inputs were assessed by comparison of selected treatment plots with two adjacent reference sites (long-term pasture and a 60–year Pinus radiata forest) on the same soil type. The effects of lime and N on soil biological quality were investigated under field and controlled environment conditions by determination of: microbial community structure (phospholipid fatty acids - PLFA), microbial biomass (total PLFA), and microbial activity (dehydrogenase activity). Soil physical (percentage water-stable aggregates) and chemical (pH, and total C and N) properties were also determined. Similarly, the effects of earthworm addition on soil biological properties were explored in a short-term glasshouse pot experiment. The role of earthworms as indicators of soil biological quality in the field was assumed by nematodes and these were assessed in field trial plots and the reference sites mentioned above. Land-use change and applications of lime and N contributed to changing the microbial community structure determined by principal component analysis of transformed PLFA data. However, the effect of lime was more pronounced in the field, while N contributed most to changing microbial community structure in the glasshouse. Mean microbial activity in the field increased from 4 µg dwt/hr without lime to 16 and 21 µg dwt/hr where lime was applied at 5 and 10 tons/hectare (t/ha), respectively. Mean microbial activity in the field was markedly higher (7-fold) than in the glasshouse at similar rates of lime. Lime application also increased soil moisture retention in the field, mean gravimetric soil moisture increased from 0.33 in control plots to 0.38 and 0.39 in plots treated with 5 and 10 t/ha lime, respectively. Lime application was associated with greater soil aggregate stability. Soils from test plots treated with 5 and 10 tons/ha lime had 45-50% water-stable aggregates compared to 34% in treatments without lime. After 16 weeks in pots, earthworm treatments increased mean plant dry matter (DM)/pot by at least 19% above the control. The increase was attributed primarily to greater N mineralization in the presence of earthworms. For the duration of the trial the earthworm species tested (Apporectodea caliginosa and Lumbricus rubellus, individually or combined) did not affect any of the measured soil microbial properties. However, the survival rate of A. caliginosa was 83% compared to 25% for L. rubellus. The control not receiving any lime or N and plots treated with 10t/ha lime and 200 kgN/ha had similar nematodes species composition, comprising 40% each of bacterial and fungal feeding nematodes. They differed markedly from the reference sites as the forest soil was dominated by plant associated species (38%) and the long-term pasture had 44% plant parasitic nematodes. Accordingly, the soil food web condition inferred from nematode faunal analysis characterized all test plots as basal, stressed and depleted, while the forest soil was categorized as highly structured and fungal dominated. The findings of this thesis demonstrated that land-use change from forest to pasture can have significant impacts on soil biological properties, earthworms can contribute to pasture productivity even in the short term, and nematode faunal analysis is a robust and reliable indicator of soil biological quality.
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Enqvist, Johan. "Involving forest-dependent communities in climate change mitigation : Obstacles and opportunities for successful implementation of a REDD mechanism in Babati District, Tanzania." Thesis, Södertörn University College, School of Life Sciences, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-3549.
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The aim of this thesis is to identify how forest management in Tanzania can contribute to global climate change mitigation while improving livelihoods of forest-dependent communities.
A mechanism for reducing emissions from deforestation and forest degradation (REDD) is meant to slow increases of atmospheric CO2 while channelling funds to developing countries. In Tanzania, pioneering work in participatory forest management (PFM) has promoted local-level control over forest resource use. The purpose of this study is to contribute to a linkage between REDD and PFM that maximises benefits for communities, forests and global climate.
Three PFM projects with relation to REDD have been studied, primarily using semi-structured interviews with villagers, district officials, project facilitators, researchers, consultants and policy-makers. Analysis consists of comparing experiences at different levels and putting them in the theoretical context of climate change and forest conservation.
The study identifies several issues: local and central government institutions cannot ensure equitable benefit sharing; cross-sectoral co-ordination to address fundamental causes of the problems is lacking; participation of local communities is not satisfactory.
However, the process is at an early stage. Current activities will hopefully contribute to a future framework that properly addresses these and other obstacles. If this is accomplished, PFM and REDD can complement each other in a positive way.
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Valentukevičius, Virgis. "Kauno apskrities miškų plėtros galimybės nenašiose žemės ūkio naudmenose." Master's thesis, Lithuanian Academic Libraries Network (LABT), 2012. http://vddb.laba.lt/obj/LT-eLABa-0001:E.02~2012~D_20120530_123110-25652.
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Lietuvoje atkūrus nepriklausomybę pasikeitė žemės ūkio gamybos ekonominiai ryšiai, rinkos realizavimo bei ekonomikos sąlygos, kurių pagrindiniu prioritetu tapo žemės ūkio pelningumas. Pasekoje to, mažiau palankiose ūkininkauti teritorijose prasidėjo spartūs žemės ūkio naudmenų renatūralizacijos procesai. Viena iš teikiamų alternatyvų ūkininkaujantiems nenašiose bei mažiau palankiose ūkininkauti teritorijose tapo miškų įveisimas ne miško žemėje.
Nenašių ir žemės ūkiui nenaudojamų žemės ūkio naudmenų apželdinimas mišku laikoma svarbia miškų ūkio plėtros priemone, kuri padėtų įgyvendinti Lietuvos miškų ūkio politikos strategijoje ir miškingumo didinimo programoje numatytus pagrindinius tikslus iki 2020 metų padidinti Lietuvos miškingumą 3 %.
Darbe atliekamas tyrimas norint nustatyti nenašių žemių apželdinimo galimybes mišku Kauno apskrityje. Šiam tikslui pasiekti buvo nagrinėjama miškų įveisimą reglamentuojantys įstatymai bei kiti teisės aktai, nustatantys pagrindinius kriterijus miško įveisimui ne miško žemėje. Taip pat atliekant tyrimą nagrinėjamos GIS technologijų panaudojimo galimybės, kurių pagalba galima nesunkiai nustatyti tinkamiausias vietas miškams įveisti pagal visus pasirinktus kriterijus.
Tyrimo metu paaiškėjo, kad Kauno apskrityje yra 39040,4 ha nenašių žemės ūkio naudmenų, kurių našumo balas yra mažesnis nei 32 balai. 31826,40 ha iš nenašių žemės ūkio naudmenų atitinka miško įveisimui keliamus pagrindinius kriterijus. Šį plotą įvertinus pagal žemės naudmenų... [toliau žr. visą tekstą]The Restoration of Lithuania’s independence changed the economic relations in agricultural production, sales market and economic conditions, with agricultural profitability becoming a key priority. As a consequence, processes of rapid agricultural land renaturalization began in the areas unfavourable to agriculture. One of the alternatives offered to farmers who own an infertile and less suitable land for farming is afforestation of a non-forest land. Afforestation of infertile and unused farmland is considered as an important means of forestry development that will help implement fundamental objectives of the Lithuanian Forestry Strategy and the Afforestation Programme to increase the Lithuanian forest coverage by 3 per cent by the year 2020. This research work is aimed at evaluating possibilities of infertile land afforestation in the Kaunas County. To achieve this objective, consideration was given to legislation regulating afforestation and establishing the basic criteria for afforestation of non-forest land. The study also looked into the use of GIS technology options that will allow to easily identify the most suitable sites for afforestation by all the selected criteria. The study showed that the Kaunas County has 39,040.4 hectares of infertile agricultural land whose performance score is less than 32. 31,826.40 hectares (81.5%) of the infertile lands meet the required essential criteria for afforestation. The assessment of the area by the actual land use established... [to full text]
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Binti, Zakaria Noor Aini. "Trade Barriers in Forest Industry between Malaysia and Europe." Phd thesis, AgroParisTech, 2011. http://pastel.archives-ouvertes.fr/pastel-00750922.
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This study analyses the international timber trade between Malaysia and Europe with respect to the importance of environmental issues on trade and the role of Malaysia as a major timber exporter to Europe. It also evaluates the comparative advantage of Malaysian wood products and the willingness of French consumers (to represent European communities) to pay for sustainable forest management. The first part gives an overview the clashes of perception between developed and developing countries on the environmental concerns over trade. It was observed that environmental standards may act as non-tariff barriers to exporting countries. In addition, the stringent requirements posed by importing countries on technical, marking and labelling to some extent provide unnecessary barriers to trade. The second part deals with the role of Malaysia as a key player in the tropical timber trade. This part evaluates the main export market for Malaysian wood products to the world. For the purpose of this thesis, the analysis focuses on the European market. From the observations, it was found that the export of wooden furniture surpassed major timber exports in 2004. However, to penetrate the European market, Malaysia has to compete with the Chinese with their lower cost tropical wood products, and Brazil with their advantage in certification and labelling of tropical wood products. In tandem with that, the commitment towards sustainable forest management at national level causes shortage of raw materials in Malaysia. To a certain extent, the internal and external factors create necessary challenges to enter the European market. In the third part, the Balassa approach was used to classify the comparative advantage of Malaysia's twenty one types of wood products in Europe. It was estimated that Malaysia had high comparative advantage only in five products which were mechanized and intermediary industrial products. The products identified were sawn wood, wooden mouldings, plywood, veneer and builders' joinery and carpentry. The remaining products had lower comparative advantage and disadvantage to export to the European market based on the Balassa index. In the last part, the estimation on the willingness to pay for sustainable forest management attributes was conducted. Besides that, additional attributes such as fair trade and wood origin were included. A questionnaire was set up using all the attributes reflected in the hypothetical wood flooring product in the market. Based on the result, consumers were willing to pay the highest for the presence of fair trade and wood origin (in this study referring to French origin); nevertheless they were still willing to pay for sustainable aspects of forest. However, the willingness to pay for all the attributes was altered depending on the respondents' knowledge of forest labelling, their attitudes towards environmental preservation, living area, education level, type of job and income level. In the overall finding of the thesis, all the results from each part were synthesized in a systemic approach simultaneously deliberating on the macro and microeconomic perspectives as well as the dimensions on demand and supply. Overall, the findings suggest that the challenges and constraints facing the Malaysian timber industry indirectly shaped the export of Malaysian wooden products. Malaysia has adapted by going into value-added products to lessen the impact of environment-related trade barriers and to circumvent the shortage of raw materials supply. Malaysia has successfully customized the wooden products to the sustainability and legality requirements of the European market by pursuing the national certification (Malaysian Timber Certification) and being committed to sustainable forest management objectives.
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Venard, Asongayi. "The Impact of World Bank’s Conditionality-Ownership Hybrid on Forest Management in Cameroon: Policy Hybridity in International Dependence Development." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etd/2349.
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Many developing countries depend on the World Bank for development assistance, which the Bank often provides with policy reform conditions. Resistance to World Bank’s conditionality caused the Bank to posit “ownership” as a country’s real assent to its development policies. The combination of ownership and conditionality invalidates the neocolonial, false-paradigm and dualism theses in explaining the international dependence development model. This study explains this model by investigating how the relationship between conditionality and ownership in the context of this model impacts forest management in Cameroon.
Integrating theoretical and methodological insights mainly from political science, economics, geosciences, and sociology, the study finds that in this model, conditionality and ownership have a hybrid relationship that fosters and hinders effective forest management in Cameroon. This finding positions policy hybridity within this model. It proposes a nouvelle way to understand international development policies’ interactions, and the effects of the interactions on natural resource management.
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Persha, Lauren. "Decentralized forest management, anthropogenic disturbance patterns and forest change in the Usambara Mountains, Tanzania." [Bloomington, Ind.] : Indiana University, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3337272.
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Thesis (Ph.D.)--Indiana University, School of Public Environmental and Affairs, 2008.Title from PDF t.p. (viewed on Jul 28, 2009). Source: Dissertation Abstracts International, Volume: 69-12, Section: B, page: 7386. Adviser: James C. Randolph.
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Bujold, Michelle. "Environmental values, a comparative study of government forest policies in Canada and Sweden." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ57093.pdf.
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Boal, Clint William 1961. "An urban environment as an ecological trap for Cooper's hawks." Diss., The University of Arizona, 1997. http://hdl.handle.net/10150/288705.
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I studied a population of Cooper's hawks (Accipiter cooperii) nesting in the metropolitan city of Tucson, Arizona, from 1994 to 1997. I identified 51 Cooper's hawk territories distributed across Tucson with pockets of nesting density as great as 1 pair/64.7 ha. Eucalyptus (Eucalyptus spp.) (70.8%), aleppo pine (Pinus halepensis ) (25.0%), and cottonwood trees (Populus fremontii) (4.2%) were used as nesting structures more frequently than expected based on availability. Nest trees were primarily located in residential yards (48.3%) and high-use recreational areas (28.3%). Nest sites had a greater basal area, canopy cover, stem density, and number of trees >10 m tall than random sites. I compared the breeding ecology of urban Cooper's hawks with those in exurban areas. Urban pairs tended to have larger clutches (urban x̄ = 3.64: exurban x̄ = 3.20) (P = 0.085) and more nestlings (urban x̄ = 3.11; exurban x̄ = 2.78) (P = 0.145) than exurban pairs. Nestling mortality, however, was greater among urban nests (51%) than exurban nests (5%). The primary cause of death among urban nestlings was trichomoniasis (80%), a disease caused by the parasitic protozoan Trichomonas gallinae ; the disease was not a mortality factor among exurban nests. Raptors develop the disease by eating infected prey. Doves (Columbidae) are hosts for the protozoan and accounted for 83% and 10% of the diet of urban and exurban Cooper's hawks, respectively. Breeding age Cooper's hawks were 99% free of infection independent of nesting area. Infection rates were greater among urban nestlings than exurban nestlings (P < 0.0001). Breeding urban Cooper's hawks have high probabilities of survival (0.792) and recapture (0.947), but the estimated juvenile survivorship is low (0.199). Age-specific fecundity and survival suggests the urban population is declining by 8% annually, but has the capacity to increase by at least 2% annually. Paradoxically, the population appears to be stable or increasing, probably due to immigration of Cooper's hawks from outside the study area. Population sinks in human altered landscapes have been described as "ecological traps" because animals are attracted to them but suffer from low productivity or high mortality once they are there. My results suggest Tucson may be an ecological trap for Cooper's hawks.
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Anand, Gautam. "Acc deaminase positive bacteria in stressed agricultural environments." Thesis, IITD, 2019. http://eprint.iitd.ac.in:80//handle/2074/8102.
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Garbark, Christopher J. "The Relationship of Red-Backed Salamander Abundance to the Direct and Indirect Use Value of Undisturbed Forest, a Timberland Mosaic of Forest, and Agriculture Land-Uses." Thesis, Indiana University of Pennsylvania, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13810330.
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Plethodon salamanders may serve as important indicators of forest ecosystem integrity due to their niche, physiological sensitivity, abundance, site fidelity, and association with forest structures. Forest ecosystems provide direct and indirect services and products that benefit society. Monitoring the quality and status of these direct and indirect use values is important to manage and maximize the benefit to people. An ecological indicator is something that may indicate the state of a system. Indicators are widely used in a variety of fields including forestry, economics, and environmental management to monitor the state of desired systems. The IndVal method is a statistical analysis used to determine the efficacy of a species as an indicator species, by determining the association between the species of interest and site groups or habitats. I sought to determine if the red-backed salamander is an indicator of forests based on the IndVal method, and if the red-backed salamander may be used as an indicator of use values. I hypothesized that red-backed salamanders may be used as an indicator of standing mature forested areas. I hypothesized that salamander abundance would be highest in forested areas and may act as an indicator species of forest habitats. I hypothesized that red-backed salamander abundance would have a positive correlation with indirect use values and a negative correlation with direct use values. The study area consisted of Forestland, Timberland, and Agriculture land-uses within northwestern Pennsylvania. I used visual encounter surveys and drift fences for capturing of red-backed salamanders (Plethodon cinereus) for abundance estimates. Visual encounter surveys were done within area constrained (10 × 10m) plots and a time constraint of roughly 30 minutes. I measured environmental variables within each plot. An N-mixture model of P. cinereus was used to estimate abundance based on repeated counts data. I used a principal components analysis (PCA) to determine which environmental variables were associated with study sites. I used a Kruskal-Wallis test and post-hoc Dunn’s test to determine differences between land-use in red-backed salamander abundance. I applied the IndVal method to red-backed salamander abundance in association to land-use and habitat. I estimated indirect use values through cost replacement methods for water purification, water cycling production, nitrate treatment, and soil erosion. I obtained direct use values through land-owners and the U.S. Forest Service archives, which the cost of production and gross value of production were used to determine the net and gross value. I used a Spearman’s Rank correlation to determine the relationship between red-backed salamander abundance and the direct and indirect use values of land-uses. The PCA 1 axis described an environmental gradient of closed to open canopy. Forestland sites had the lowest sunlight values, Agriculture having the highest, and Timberland intermediate between the two. Canopy percent cover was the most informative variable in the N-mixture model. Red-backed salamander abundance was greatest, mean = 434, on Forestland sites and was significantly (p-value < 0.05) different from Timberland and Agriculture. The red-backed salamander was highly associated with Forestland with an indicator species value of 0.876, and 0.972 for forests. Red-backed salamanders held a significant strong positive relationship with indirect use values, rho = 0.84. P. cinereus abundance had a significant strong negative relationship with gross direct use values, rho = –0.95, and net direct use values, rho = –0.92. The strong correlation between P. cinereus abundance and indirect use values suggest that red-backed salamander abundance may have applications as an indicator of indirect use values for forest ecosystems.
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Whitman, Karie L. "Improving Conservation Outcomes in a Biodiversity Hotspot: Alternative Agriculture Techniques in Maromizaha Forest, Madagascar." Ohio University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1493822021804859.
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Taillon, Kate. "Modeling surface complexation relationships in forest and agricultural soil." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82435.
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The adsorption behaviour of trace metals in soil may provide us with a way to more accurately predict and assess the toxicity of metals in the environment. This thesis reports efforts to apply surface complexation modeling to agricultural and forest soil and to relate model parameters to common soil properties. This study considered Ca, Cd, Cu, Pb and Zn but the methods here could be applied to other metals. In Chapter 2, the surface charge and adsorption behaviour of a set of Ap horizons was characterised using back-titration and batch adsorption techniques. With the objective of simplifying the application of the NICCA model to surface charge and cation adsorption in whole soils the parameters of the NICCA model were related to soil properties (Chapter 3). Four of the six surface charge parameters could be predicted from soil properties and this enabled me to reasonably predict the surface charge of a second group of soils from soil properties. These results suggest that it is possible to make reasonable predictions about the surface charge and adsorption behaviour of a given type of soil using some easily measurable soil properties and a set of generic NICCA adsorption parameters for that soil type. In Chapter 4 this idea is applied to the determination of lime requirement for the agricultural soils.
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Mello, Kaline de. "Forest cover and water quality in tropical agricultural watersheds." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/11/11152/tde-03082017-101658/.
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Tropical forests are under continual threat due to deforestation and forest fragmentation processes which are driven by the economic activities growth, mainly agriculture. Replacing forest with other land uses can cause severe impacts on river water quality, altering its physical, chemical and biological characteristics. The Atlantic Forest, in particular, had its original vegetation cover reduced to about 11%, wherein the crop lands expansion and urban sprawl still threatening this important ecosystem and the ecosystem services that it provides. In this sense, the main objective of this study was to investigate the relation between forest cover and water quality of tropical agricultural watersheds. For that, six experimental watersheds with different percentage of forest cover were selected in the Sarapuí River watershed, State of São Paulo, Brazil. Water samples were collected during a hydrologic year to obtain water quality parameters that represent impacts induced by anthropic activities. According to the percentage of forest cover, the watersheds were denominated as \"forested\", when they presented more than 55% of forest cover, and \"degraded\", with less than 35%. Multivariate statistical models were applied to identify differences between these two groups. In a second moment, the relation of land use/land cover within the watershed and within its respective riparian zone, represented in this study by the Permanent Preservation Areas (PPA), with water quality was compared through mixed models and redundancy analysis to identify the main factors that influenced water quality variability. Lastly, a watershed simulation modeling was applied to verify the impact of riparian forest restoration on water quality of the Sarapuí River watershed, wherein each experimental watershed was represented by a sub-watershed in the model. The results showed that the degraded watersheds presented higher values of solids, turbidity, nutrients and coliforms, besides presenting greater temporal data variability compared to forested watersheds. This variation is associated with the stream flow changes during the year. In general, forest cover was related to good water quality, while agriculture and urban areas were responsible for the water quality degradation. Pasture presented mixed impacts, but it was not generally correlated with poor water quality. The water quality parameters responded differently to the influence of land-use/land-cover patterns in the watershed and riparian zone, but the overall water quality is better explained by the landscape composition within the watershed. Nevertheless, the watershed simulation indicated that PPA restoration reduces the sediment and nutrients loading into the river. Thus, it is possible to conclude that tropical forest plays a fundamental role in the water resources conservation, reducing impacts of human activities in watersheds and the watershed management with forest restoration strategies for the entire watershed is critical for the maintenance of water quality to water supply, despite the importance of the riparian zone.As florestas tropicais estão sob constante ameaça devido ao processo de desmatamento e fragmentação florestal impulsionado pelo crescimento das atividades econômicas, em especial, a agricultura. A substituição de áreas florestadas por outros usos do solo pode causar impactos severos na qualidade da água de rios, alterando suas características físicas, químicas e biológicas. A Mata Atlântica, em especial, teve sua cobertura original reduzida a cerca de 11%, sendo que a expansão de terras cultiváveis e urbanização ainda ameaçam esse importante ecossistema e os serviços ecossistêmicos prestados por ele. Nesse sentido, este estudo propôs investigar a relação da cobertura florestal com a qualidade da água de microbacias agrícolas tropicais. Para tanto, foram selecionadas seis microbacias experimentais com diferentes porcentagens de cobertura florestal na bacia do rio Sarapuí, Estado de São Paulo, Brasil, onde foram feitas coletas de amostras de água por um ano hidrológico para a obtenção de parâmetros que representassem alterações na água induzidas por atividades antrópicas. Inicialmente as microbacias foram classificadas em \"florestadas\" e \"degradadas\", e modelos estatísticos multivariados foram aplicados para identificar diferenças entre os grupos. Em um segundo momento comparou-se a relação do uso e cobertura do solo na microbacia e na Área de Preservação Permanente (APP) com a qualidade da água utilizando-se modelos mistos e análise de redundância para identificar os principais fatores que influenciam a variabilidade da qualidade da água. Por último foi gerado um modelo hidrológico para simular o impacto da restauração da floresta ripária na qualidade da água da bacia do rio Sarapuí onde cada microbacia experimental desse estudo foi representada por uma sub-bacia do modelo. Os resultados mostram que as microbacias degradadas apresentam valores maiores de sólidos, turbidez, nutrientes e coliformes. Além disso, apresentam maior variabilidade temporal dos dados em relação às microbacias florestadas associada às alterações da vazão do rio. Em geral, a cobertura florestal foi relacionada à boa qualidade da água, enquanto que agricultura e ocupação urbana foram os usos do solo responsáveis pela degradação da qualidade da água. O uso pastagem apresentou impactos mistos, porém no geral não foi correlacionado à qualidade da água ruim. Os parâmetros de qualidade da água responderam de forma diferente quanto à influência dos padrões de uso e cobertura do solo na microbacia e na APP, porém, considerando-se todos parâmetros em conjunto, a qualidade da água é melhor explicada pela composição da paisagem da microbacia. Ainda assim, a simulação do modelo indicou que a restauração das APPs reduz a carga de sedimentos e nutrientes para o rio. Com isso, conclui-se que a floresta tropical tem papel fundamental na conservação dos recursos hídricos, reduzindo impactos das atividades humanas exercidas nas microbacias e que, apesar da importância das APPs na redução de poluentes para o rio, o manejo de bacias com estratégias de restauração florestal para toda a microbacia é extremamente importante para a manutenção da qualidade da água para abastecimento.
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Li, Rui. "Solar pyrolysis of agricultural, forest and metal-contaminated biomass." Thesis, Perpignan, 2020. http://www.theses.fr/2020PERP0026.
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La biomasse est une source d'énergie renouvelable qui peut contribuer à résoudre la crise énergétique et les problèmes environnementaux. La pyrolyse est un procédé thermochimique de conversion la biomasse en biocarburants. L'énergie solaire permet d’améliorer le bilan matière et énergie de la pyrolyse de la biomasse pour produire des carburants, des produits chimiques et des biomatériaux transportables. Dans cette étude, nous avons étudié expérimentalement la pyrolyse solaire de sous-produits agricoles, forestiers et de bois contaminé par des métaux lourds. Dans le cas de la biomasse de sous-produits agricoles et forestiers, la sciure de pin, les noyaux de pêche, les tiges et marcs de raisin, a été utilisée comme matières premières dans un réacteur de laboratoire. Nous avons étudié l'influence des conditions opératoires (c.-à-d. la température de 800 à 2000°C, la vitesse de chauffage de 10 à 150°C/s et la composition de lignocellulose) sur les rendements de production des produits de la réaction (c.-à-d. gaz, tar (liquide) et char (solide)) et la composition du gaz de synthèse. Généralement le rendement en gaz augmente avec la température et la vitesse de chauffe pour les divers types de résidus de biomasse, tandis que le rendement en liquide progresse de façon opposée. Les teneurs en lignine, hémicellulose et cellulose, ainsi que la taille des pastilles d’échantillon, des sous-produits étudiés ont un impact sur la distribution des produits de pyrolyse solaire rapide. La teneur en lignine est associée à des rendements plus élevés en char et en liquide, mais moins en gaz. La pyrolyse de l'hémicellulose produit plus de composés volatils, mais moins de char et de tar que la pyrolyse de la cellulose.La pyrolyse solaire des déchets de litière de poulet et des pailles de riz de différentes tailles de particules (280 et 500 µm) a été effectuée dans différentes conditions solaires afin d'étudier les paramètres de fonctionnement optimaux, tels que la température, la taille des particules et la vitesse de chauffe, pour produire des gaz de pyrolyse à haute valeur calorifique. La température a l'effet le plus important sur le rendement en gaz pendant la pyrolyse. Les produits gazeux à partir de la pyrolyse de la biomasse assistée par l'énergie solaire contiennent une forte concentration de produits combustibles.La biomasse peut être contaminée par des métaux lourds. Des expériences ont été conçues pour étudier les effets des métaux lourds (cuivre et nickel) sur les produits de pyrolyse solaire du saule imprégné. Les résultats de cette étude indiquent que la pyrolyse solaire de la biomasse contaminée par des métaux lourds permet de produire du gaz de synthèse riche en hydrogène et monoxyde de carbone. De plus, les effets de ces métaux lourds sur la composition chimique, la structure et la morphologie du charbon de pyrolyse du saule imprégné ont été étudiés. Les résultats prouvent que la température de pyrolyse affecte les propriétés du charbon.Un modèle de conduction a été développé pour décrire le phénomène de pyrolyse à partir de l’évolution du profil de température à l'intérieur des pastilles. Un schéma cinétique de la littérature impliquant les réactions primaires et secondaires est adopté pour effectuer les simulations des transferts couplés. Une méthode aux différences finies est utilisée pour résoudre l'équation de transfert de chaleur avec un schéma explicite. Le modèle est résolu pour deux dimensions (c'est-à-dire le temps et la position axiale) afin de le rendre plus simple et de gagner du temps de calculBiomass, as a renewable energy source, can contribute to relieving the energy crisis and environmental pollutions. Pyrolysis is an attractive thermochemical process to convert biomass into biofuels. Solar energy processes improve the heat and mass balance of the biomass pyrolysis to produce transportable fuels, chemicals, and biomaterials. In the present study, solar pyrolysis of agricultural and forestry by-product biomass and metal-polluted wood has been examined. Pine sawdust, peach pit, grape stalk, and grape marc, were used as the raw materials as the agricultural and forestry by-products in a series of solar pyrolysis experiments in a lab-scale reactor. We studied the impacts of operating conditions (i.e., temperature from 800 to 2000°C, heating rate from 10 to 150°C/s, and lignocellulose composition) on the product yields (i.e., gas, tar, and char) and syngas composition. The gas yield of different biomass residues generally increases with the temperature and heating rate, while the liquid yield shows an opposite trend. Lignin, hemicellulose, and cellulose contents, as well as pellet size, of the by-products studied have an impact on the product profile under fast solar pyrolysis. Lignin content is associated with greater char and tar yields, but less gas yields. Hemicellulose pyrolysis produces more volatiles, but less char and tar yields than cellulose pyrolysis.Solar pyrolysis of chicken-litter waste and rice husk of different particle sizes (280 and 500 µm) was performed at different solar conditions aiming at investigating optimal operating parameters, such as temperature, particle size, and heating rate, to produce pyrolysis gasses with high calorific value. Temperature was found to have the highest effect on the gas yield during pyrolysis. Gases produced from solar assisted biomass pyrolysis have high concentration of combustible products which can be directly used as fuels.Biomass can be contaminated by heavy metals. Experiments were carried out to study the effects of heavy metals (copper and nickel), in combination with heating temperature and heating rate, on solar pyrolysis products of impregnated willow. Results of the investigation indicate that solar pyrolysis of heavy metal contaminated biomass is promising to produce valuable syngas such as hydrogen and carbon monoxide. Additionally, the effects of these heavy metals on the chemical composition, structure, and morphology of pyrolysis char from the impregnated willow were studied. Results prove that heavy metal and solar pyrolysis temperature affect the char properties. A conduction model was developed to describe the behavior of temperature inside the pellets. A kinetic scheme from literature involving the primary and the secondary reactions is adopted to carry out the simulations of temperature. A finite difference method was used for solving the heat transfer equation with an explicit scheme. The model is solved for two dimensions (i.e., time and axial position) in order to make it simpler and save computational time
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Ussiri, David A. N. "Organic matter chemistry and dynamics in a forest soil affected by clear-cutting disturbance." Related Electronic Resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2003. http://wwwlib.umi.com/cr/syr/main.
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Herrera-Herrera, Jose Rafael. "Assessment of Organochlorine Pesticide Exposures in Riparian Ecosystems and Environmental Education in Southeastern Mexico." Miami University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=miami1401975159.
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Pinheiro, Fabiola M. R. "Effects of forest fires and clear-cutting on mercury loading to boreal lakes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0034/MQ64431.pdf.
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Evans, Alison. "The impact of selective beech (Nothofagus spp.) harvest on litter-dwelling invertebrates and the process of litter decomposition." Lincoln University, 1999. http://hdl.handle.net/10182/1717.
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Minimising the potential impact of forest management requires an understanding of the key elements that maintain forest diversity and its role in ecological processes. Invertebrates are the most diverse of all biota and play important roles in maintaining forest processes. However, little is known about invertebrates in New Zealand's beech forests or the degree to which selective beech harvest might impact on their diversity and ability to carry out ecosystem processes. Studying ecosystem responses to disturbance is considered vital for understanding how ecosystems are maintained. One of the main objectives of this research was to assess whether litter-dwelling invertebrates were susceptible to the impacts of selective harvest and, if so, whether they could be used as indicators of forest health. Changes in invertebrate diversity could have important implications for nutrient cycling and primary production in forests. Litter-dwelling invertebrates contribute to the process of decomposition by increasing the surface area of the leaves, mixing soil organic matter and by infecting leaf particles with soil microbes. This investigation into the function of invertebrates in beech forest was carried out in the context of ecological theories which relate diversity to ecosystem stability and resilience. A replicated study was established in Maruia State Forest (South Island, New Zealand) to assess the potential biotic and abiotic impacts of sustainable beech harvest. Litter-dwelling invertebrates and environmental factors were monitored during 1997, before harvest, to determine how much variability there was between study sites. Specifically, litter pH, light intensity, litter fall, litter temperature, moisture as well as invertebrate abundance and diversity were compared before and after selective harvest. On 17 January 1998, two to three trees were selectively harvested from three of the nine study sites. On 15 February 1998 a similar number of trees were winched over or felled manually to create artificial windthrow sites. The remaining three undisturbed sites were used as controls. Invertebrates belonging to the detritivore guild were assessed from litter samples and a series of litter-bags containing pre-weighed leaf litter which were placed in each of the sites to assess rates of litter decomposition. Millipedes (Diplopoda: Polyzoniidae, Schedotrigonidae, Dalodesmidae, Habrodesmidae, Sphaerotheridae), earthworms (Oligochaeta: Annelida), tipulid larvae (Diptera: Tipulidae), weevils (Coleoptera: Curculionidae), moth larvae (Lepidoptera: Oecophoridae, Tortricidae and Psychidae), slaters (Isopoda: Styloniscidae), Oribatid mites (Acarina: Cryptostigmata) and landhoppers (Crustacea: Amphipoda) were extracted from the litter-bags and their abundance and diversity was compared between the three treatments. Weight loss from the litter-bags and the carbon and nitrogen content of litter were used to measure the rate of decomposition in each treatment. An additional study investigated whether exclusion of invertebrates from leaf litter resulted in reduced rates of decomposition. The results indicated that there was an increase in light intensity and a small increase in temperature following selective harvest and artificial windthrow. There was no significant difference in litter moisture or the amount of litter fall between the treatments. Invertebrate abundances were significantly affected by season but did not appear to be affected by selective harvest or artificial windthrow. The diversity of invertebrates remained relatively constant throughout the year, as did the rate of decomposition. When invertebrates were excluded from the leaf litter there was no consequential effect on the rate of litter decomposition. This suggests that there may be compensatory mechanisms taking place between the trophic levels of the food web to maintain processes and that direct links between invertebrates and decomposition are relatively weak. In conclusion, it appears that the effects of selective beech harvest on forest-floor processes were minimal and are comparable to those created by natural windthrow disturbance. It also appears that macroclimatic effects such as seasonal climatic effects have a large effect on forest biota. As none of the invertebrates studied appeared to be detrimentally affected by selective harvest and as there was no direct link demonstrated with decomposition, it was considered inappropriate to advocate the use of this group of invertebrates as indicators of sustainable forest management. The results from this study provide information which may help inform decisions on the future management of diversity in beech forest ecosystems.
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Jantz, Claire Ann. "Analyzing forest change and policy in Washington, DC suburban environments." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/2642.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2005.Thesis research directed by: Geography. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Pfister, Thomas [Verfasser]. "Robust Localization for Mobile Robots in Forest Environments / Thomas Pfister." München : Verlag Dr. Hut, 2017. http://d-nb.info/1135596786/34.
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Tremblay, Jean-François, and Jean-François Tremblay. "Forest inventory with a lidar-equipped robot for difficult environments." Master's thesis, Université Laval, 2019. http://hdl.handle.net/20.500.11794/37634.
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La foresterie est une industrie majeure dans plusieurs parties du monde. Elle dépend de l’inventaire forestier, qui consiste en la mesure des attributs des arbres. Dans ce mémoire, nous proposons l’utilisation de la cartographie 3D, basée sur l’algorithme itervative closest point, pour automatiquement mesurer des diamètres d’arbres à partir d’observations d’un robot mobile. Bien que des études précédentes démontraient le potentiel d’une telle technologie, elles présentaient des lacunes en terme de rigueur d’analyse et ne fonctionnaient pas dans des environnements forestiers difficiles. Nous avons validé plusieurs méthodes pour l’estimation de diamètre, dont deux nouvelles, avec un jeu de données nouveau et varié comportant quatre sites forestiers, 11 trajectoires de robot totalisant 1458 observations d’arbre et 1.4 hectares de forêt. De plus, nous faisons des recommendations sur le déploiement de robots mobiles dans un contexte forestier. Nous concluons que notre méthode de cartographie est utilisable dans le contexte de l’inventaire forestier automatisé, avec notre meilleure méthode donnant une erreur quadratique de 3:45 cm pour notre jeu de données en entier et 2:04 cm dans des conditions idéales, c’est-à-dire une forêt mature et espacée.La foresterie est une industrie majeure dans plusieurs parties du monde. Elle dépend de l’inventaire forestier, qui consiste en la mesure des attributs des arbres. Dans ce mémoire, nous proposons l’utilisation de la cartographie 3D, basée sur l’algorithme itervative closest point, pour automatiquement mesurer des diamètres d’arbres à partir d’observations d’un robot mobile. Bien que des études précédentes démontraient le potentiel d’une telle technologie, elles présentaient des lacunes en terme de rigueur d’analyse et ne fonctionnaient pas dans des environnements forestiers difficiles. Nous avons validé plusieurs méthodes pour l’estimation de diamètre, dont deux nouvelles, avec un jeu de données nouveau et varié comportant quatre sites forestiers, 11 trajectoires de robot totalisant 1458 observations d’arbre et 1.4 hectares de forêt. De plus, nous faisons des recommendations sur le déploiement de robots mobiles dans un contexte forestier. Nous concluons que notre méthode de cartographie est utilisable dans le contexte de l’inventaire forestier automatisé, avec notre meilleure méthode donnant une erreur quadratique de 3:45 cm pour notre jeu de données en entier et 2:04 cm dans des conditions idéales, c’est-à-dire une forêt mature et espacée.
Forestry is a major industry in many parts of the world. It relies on forest inventory, which consists of measuring tree attributes. In this thesis, we propose the use of 3D mapping, based on the iterative closest point algorithm, to automatically measure tree diameters in forests from mobile robot observations. While previous studies showed the potential for such technology, they lacked a rigorous analysis of diameter estimation methods in challenging forest environments. Here, we validated multiple diameter estimation methods, including two novel ones, in a new varied dataset of four different forest sites, 11 trajectories, totalling 1458 tree observations and 1.4 hectares. We provide recommendations for the deployment of mobile robots in a forestry context. We conclude that our mapping method is usable in the context of automated forest inventory, with our best method yielding a root mean square error of 3:45 cm for our whole dataset, and 2:04 cm in ideal conditions consisting of mature forest with well spaced trees.
Forestry is a major industry in many parts of the world. It relies on forest inventory, which consists of measuring tree attributes. In this thesis, we propose the use of 3D mapping, based on the iterative closest point algorithm, to automatically measure tree diameters in forests from mobile robot observations. While previous studies showed the potential for such technology, they lacked a rigorous analysis of diameter estimation methods in challenging forest environments. Here, we validated multiple diameter estimation methods, including two novel ones, in a new varied dataset of four different forest sites, 11 trajectories, totalling 1458 tree observations and 1.4 hectares. We provide recommendations for the deployment of mobile robots in a forestry context. We conclude that our mapping method is usable in the context of automated forest inventory, with our best method yielding a root mean square error of 3:45 cm for our whole dataset, and 2:04 cm in ideal conditions consisting of mature forest with well spaced trees.
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Mattias, Tjernqvist. "Backpack-based inertial navigation and LiDAR mapping in forest environments." Thesis, Umeå universitet, Institutionen för fysik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-136870.
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Creating 3D models of our surrounding world has seen a rapid increase in research and development over the last few years. A common method is to use laser scanners. Mapping is done either by ground based systems or airborne systems. With stationary ground-based laser scanning, or terrestrial laser scanning (TLS), it is possible to obtain high accuracy point clouds. But stationary TLS can often be a cumbersome and time-demanding task due to its lack of mobility. Because of this, much research has gone into mobilised TLS systems, referred commonly to as mobile laser scanning (MLS). Georeferencing point clouds to a world coordinate system is a difficult task in environments where global navigation satellite systems (GNSS) is unreliable. One such environment is forests, where the GNSS signal can be blocked, absorbed or reflected from the trees and canopy. Accurate georeference of points clouds for MLS systems in forests is difficult task that can be solved by using additional measurement instruments and post-processing algorithms to reduce the accumulation of errors, also known as drift. In this thesis a backpack-based MLS system to be used in forests was tested. The MLS system was composed of a GNSS, an inertial navigation unit (INS) and a laser scanner. The collected data was post-processed and analyzed to reduce the effects of detecting multiple ground layers and multiples of the same tree due to drift. The post-processing algorithm calculated tree and ground features to be used for adjusting the point cloud in the horizontal and vertical planes. The forest survey was done for an area roughly 40 meters in diameter. The MLS data was compared against TLS data as well as manual caliper data - where the caliper data was only measured in an area roughly 24 meters in diameter. The results indicated that the effects of multiple ground layers and multiple tree copies were removed after post-processing. Out of the total 214 TLS trees, 185 managed to be co-registered to MLS trees. The root mean square error (RMSE) and bias of the diameter at breast height (DBH) between the MLS andTLS data were 27.00 mm and -9.33 mm respectively. Co-registrationof the MLS and manual caliper data set gave 36 successful matches out of the total 43 manually measured DBH. The DBH RMSE and bias were 16.95 mm and -10.58 mm respectively. A Swedish TLS forest study obtained a DBH RMSE and bias (between TLS and caliper) of approximately 10 mm and +0.06 mm respectively. A Finnish backpack MLS forest study obtained a DBH RMSE and bias (between MLS and TLS) of 50.6 mm and +11.1 mm respectively. Evaluating the difference in radius at different heights along the tree stems between the MLS and TLS revealed a slight dependence on height, as the radius difference increased slightly closer to the stem base. The results indicated that backpack-based MLS systems has the potential for accurate lidar mapping in forests, and future development is of great interest to improve this system further.
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Estabrook, Tracy Starr. "Burrow selection by burrowing owls in an urban environment." Thesis, The University of Arizona, 1999. http://hdl.handle.net/10150/278687.
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I surveyed parts of Tucson, Arizona to determine numbers of burrowing owl (Speotyto cunicularia) burrows present, identify characteristics associated with burrow sites, and assess reproductive success. I measured habitat characteristics at 48 winter, 58 breeding, and 48 random burrows. Random burrows were closer to perches (P) and farther from wash banks (P) than were active burrows, and had smaller entrance dimensions (P). Winter burrows were farther from human activity than were breeding burrows (P). Active sites had less total vegetation, and less visual obscurity than did random sites. Owls may have selected open sites to facilitate detection of predators or prey. Urbanization sometimes created conditions which appeared to attract owls, but also destroyed burrows. An average of 2.31 young fledged from 116 active burrows during 1997-1998. While comparable to other studies of burrowing owls occupying urban environments, this was lower than rates typically reported for the species.
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FERRE', CHIARA. "Monitoring of greenhouse gas emissions from agricultural and forest soils." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2009. http://hdl.handle.net/10281/7483.
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Global climate change is becoming a central issue in contemporary science as well as politics. There is a long-lasting debate about the cause of the climate change: anthropogenic activity versus the natural cycle. However, a scientific consensus is coming a conclusion that the contemporary climate change is mainly caused by anthropogenic emissions of the greenhouse gases (GHG), including carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4).
The main objective of the thesis is the monitoring of such GHG emissions from two ecosystem types: a forest and a rice paddy ecosystem. The forest site is a EMEP experimental station, taking part of the activity of GHG-AGOLU of FP7-JRC project, while the agricultural ecosystem was included in the CarboEurope project and represents also a Level 3 site in the frame of NitroEurope project. The gas monitoring was carried out in 2008.
The thesis is composed by 4 chapters, corresponding to specific objectives. The first chapter is relative to the study of the spatial variability of the main soil chemical and physical properties on the basis of which the gas monitoring points were selected. The second and the third chapters are relative to a cropland site. In particular, the second chapter includes monitoring data of CH4, N2O and CO2 fluxes from the paddy field, both during the crop growth season and the fallow period, and the validation results of the DeNitrification DeComposition (DNDC) model, a process-oriented biogeochemical model used for simulating soil gas emissions from the paddy field, are reported. The third chapter contains the study of characterization of microbial community composition using phospholipid fatty acid analysis (PLFA), at eight sampling dates representative of different soil conditions and crop stages and consequently characterized by distinct soil greenhouse emission rates.
The fourth and last chapter includes the monitoring study of soil respiration in a forest site and its partitioning into autotrophic and heterotrophic components, applying the indirect linear regression method.
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Welch, David P. "Multidisciplinary approaches to the study of forest dynamics in south central Indiana and southern Illinois." [Bloomington, Ind.] : Indiana University, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3278462.
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Thesis (Ph.D.)--Indiana University, School of Public and Environmental Affairs, 2007.Source: Dissertation Abstracts International, Volume: 68-10, Section: B, page: 6564. Adviser: Vicky Meretsky. Title from dissertation home page (viewed May 20, 2008).
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Bert, Daniel G. (Daniel George) Carleton University Dissertation Biology. "A multiscale analysis of nested species subsets of forest birds in agricultural landscapes near Ottawa, Canada." Ottawa, 2001.
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Malatji, Pholoso. "Processing of wood and agricultural biomass for gasification." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/2937.
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Thesis (MScFor (Forest and Wood Science))--University of Stellenbosch, 2009.ENGLISH ABSTRACT: Wood waste, when used for gasification is commonly pressed into briquettes, especially if no uniform particle size is available. This densification reduces problems of handling, storage and transportation and improves the combustion performance because of a more uniform fuel size. Briquettes have to be mechanically strong enough to be handled. Cohesive strength is provided by residual moisture and lignin present in the wood. The lignin acts as a natural binder. However, the briquetting process becomes more complicated if one wants to add other agricultural waste products that do not necessarily contain lignin as binders,, In this study we have investigated various briquetting process parameters, such as mixing ratios of briquettes containing wood chips, grape skins and chicken litter, moisture content and press time. The aim was to determine the optimum process parameters that allow the production of briquettes, containing a blend of biomaterials that are mechanically stable to allow further handling but yield high energy content at the same time.
AFRIKAANSE OPSOMMING: Wanneer houtafval vir vergassing gebruik word en die partikelgrootte daarvan varieer, word die materiaal normaalweg in ’n brikket gedruk. Brikketvorming vergemaklik opberging, hantering en vervoer. Weens die meer uniforme grootte en vorm van die brikkette is verbranding daarvan heelwat meer doeltreffend. Brikkette moet egter meganies sterk genoeg wees om hanteer te kan word. Die kohesiewe sterkte word deur residuele vog en lignien, wat as natuurlike bindmiddel in hout aanwesig is, verskaf. Indien ander materiale soos landbouafval, wat noodwendig geen lignien bevat nie egter gebruik word, word die brikketvormingsproses meer kompleks. In hierdie ondersoek is verskeie brikketvormingsparameters evalueer. Mengverhoudings van brikkette wat houtspaanders, druiwedoppe en hoendermis bevat, asook invloed van materiaalvoggehalte en druktyd is bestudeer. Die doel was om die optimale materiaal- en prosesparameters vas te stel wanneer ’n mengsel van biomateriale gebruik word om brikkette te lewer wat meganies sterk genoeg is maar steeds die hoogste energieopbrengs lewer.
Centre for Renewable and Sustainable Energy Studies
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Haslem, Angie, and angie haslem@deakin edu au. "Landscape Pattern, Countryside Heterogeneity and Bird Conservation in Agricultural Environments." Deakin University. Life and Environmental Sciences, 2008. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20090114.101341.
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Agricultural environments are critical to the conservation of biota throughout the world. This is due both to the limited extent of current reserve systems and the large, and still expanding, proportion of terrestrial environments already dominated by agricultural land-uses. Consequently, there is a growing call from scientists around the world for the need to maximise the conservation value of agricultural environments. Efforts to identify key influences on the conservation status of fauna in agricultural landscapes have taken complementary approaches. Many studies have focussed on the role of remnant or semi-natural vegetation, and emphasised the influence on biota of spatial patterns in the landscape. Others have recognised that many species use diverse countryside elements (matrix habitats) within farmland, and emphasise the benefits of landscape heterogeneity for conservation. Here, these research themes have been combined. This study takes a whole-of-landscape approach to investigating how landscape pattern and countryside heterogeneity influence the occurrence of birds in agricultural environments. Birds were sampled in 27 agricultural mosaics, each 1 km x 1 km in size (100 ha), in Gippsland, south-eastern Australia. Mosaics were selected to incorporate variation in two landscape properties: the cover of native vegetation, and richness of different types of element (i.e. land-uses/vegetation types). In each mosaic, 15 fixed sampling locations were stratified among seven different elements in proportion to their cover in the mosaic: native vegetation, linear vegetation, tree plantation, scattered paddock trees, pasture, wetlands and farm dams. Six point counts of birds were undertaken at all sample points in each mosaic: three each in the breeding and non-breeding months of a one-year period (October 2004 August 2005). Independent measures of the composition, configuration, and heterogeneity of elements in the mosaic had differing effects on the richness of bird species recorded in these same mosaics. Sub-groups of birds based on habitat requirements responded most strongly to the extent of preferred element types in mosaics. Woodland birds (those of greatest conservation concern in farmland environments in Australia) were richer in mosaics with higher cover of native vegetation while open-tolerant species responded to the extent of scattered trees. In contrast, for total species richness, mosaic heterogeneity (richness of element types) and landscape context (cover of native vegetation in surrounding area) had the greatest influence. Mosaic structural properties also influenced the composition of entire bird assemblages in study mosaics. Avifaunal composition showed systematic variation along two main gradients which were readily interpreted in relation to landscape properties: 1) a gradient in the cover of wooded vegetation and, 2) the proportional composition of vegetation types in the mosaic. These gradients represent common trajectories of landscape modification associated with agricultural development: namely, the removal of wooded vegetation and the replacement of native species with exotic vegetation (e.g. crops and plantations). Species possessing different characteristics in relation to three avian life-history traits (nest type, feeding guild and clutch size) varied significantly in their position along these gradients of landscape modification. Species with different nesting requirements showed a strong relationship with the gradient in wooded vegetation cover while species belonging to different feeding guilds were influenced by the gradient defined by the replacement of native vegetation with exotic species. More bird species were recorded in native vegetation than in any other type of element sampled in this study. Nevertheless, most countryside elements had value for many species; particularly structurally complex elements such as scattered trees and tree plantation. Further, each type of landscape element contained different bird assemblages. Species that were recorded in a greater number of different types of landscape element were also recorded in more mosaics. This was true for all species and for woodland birds, and indicates that species that can use a greater range of countryside elements may have an increased tolerance of future landscape modification. The richness of woodland species at survey sites in different elements was influenced by features of the mosaic in which they occurred. Notably, the richness of woodland bird species recorded at sites in scattered trees and pasture increased with a greater cover of native vegetation in the overall mosaic. Of the overall pool of woodland bird species documented in the broader study region, 35% of species were not recorded in the agricultural mosaics sampled here. While many of these species were uncommon in the study area, or were associated with vegetation communities infrequently sampled in mosaics, this shows that conservation efforts in agricultural landscapes will not be appropriate for all species. For those woodland species that were recorded, measures of the extent of wooded vegetation cover had a strong, positive influence on the frequency of occurrence of individual species in mosaics. Thus, individual species of woodland bird occurred more frequently in mosaics with a greater cover of wooded vegetation. Nine woodland species showed a stronger response to measures of vegetation cover that included tree plantation and/or scattered trees than to the cover of native vegetation alone. For these species, structurally complex countryside elements provide valuable supplementary habitat at the landscape scale. Results of this study show that landscape properties influence the occurrence of birds in agricultural mosaics. The extent of cover of element types, particularly native vegetation, had the strongest influence on all measures of bird occurrence in mosaics. Thus, native vegetation is vital for the persistence of birds in farmland landscapes and is the primary element on which conservation efforts in these environments depend. Nevertheless, with careful management, countryside elements may provide additional conservation benefits for many bird species. Countryside elements made an important contribution to landscape heterogeneity, the landscape property with greatest influence on overall bird richness in mosaics. Countryside elements also increased the structural complexity of cleared agricultural land, and so have the capacity to enhance connectivity in fragmented landscapes. A focus on these factors (landscape heterogeneity and structural complexity) will provide the greatest opportunities for using countryside elements to increase the conservation value of farmland environments for native fauna. The relatively small scale of this study indicates that the cumulative effect of even small elements in farm mosaics contributes to the structural properties of entire landscapes. Critically, this emphasises the important contribution that individual landholders can make to nature conservation in agricultural environments.
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Cesar, Ricardo Gomes. "Local and landscape drivers of tropical forest regeneration in agricultural landscapes of the Atlantic Forest of Brazil." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-16072018-173459/.
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Forests established through native seedling planting (PL) and the establishment of secondary forests through natural regeneration (SF) are the main outcomes of large scale forest restoration. The decision making process of these approaches is conditioned by resilience. But the different outcomes of these approaches are as important as the decision making. SF are heterogeneous and - although there is a growing literature of the drivers of forest establishment - few works analyzed drivers of attributes of these recently established forests. In this context, our work aims to identify the differences between PL and SF and the local and landscape variables that affect SF attributes. To do so, we sampled the tree community in seasonal semideciduous forests of the Atlantic Forest established naturally (SF) and PL in agricultural landscapes in the Corumbataí Watershed, São Paulo State, Brazil. We observed that PL has similar biomass to SF and higher species richness. However, PL also showed lower abundance of young trees, animal-dispersed trees and lianas. Species composition between PL and SF also differs. SF established in abandoned eucalypt plantings showed species richness and biomass of native species similar to other SF forests. However, SF attributes vary greatly. In this context, SF show a large potential for providing food for fauna and storing carbon in a cost-efficient way. While PL can also provide these benefits, it may have its long-term sustainability compromised by the lack of regenerating trees. We then proceeded to investigate drivers of the heterogeneity observed in SF using generalized linear mixed models to estimate the effect of local and landscape variables on the biomass, species density and basal area of animal-dispersed trees of the SF sampled. SF surrounded by sugarcane plantations had lower biomass and basal area of animal-dispersed trees, while native forest cover in the landscape increased species density of SF. Forest age showed little or no importance in predicting SF attributes. These results highlight the importance of low impact agricultural practices and of strategies that increase native forest cover in agricultural landscapes, in order to increase the potential of SF to provide ecosystem services and conserve taxonomic diversity. The choice between establishing PL or fomenting SF for forest restoration is conditioned to the local and landscape context where restoration actions will be carried out. Although both approaches can potentially fulfill the objectives of restoration projects, special attention must be given to the recruitment of new individuals to maintain PL sustainability, while less impacting agricultural practices and more forested agricultural landscapes may increase the SF potential to provide ecosystem services and conserve biodiversity.Florestas estabelecidas pelo plantio de mudas de espécies nativas (PL) e por meio do estabelecimento de florestas secundárias pela regeneração natural (FS) são as principais comunidades geradas durante a restauração florestal em larga escala. A escolha dessas estratégias está condicionada potencial de regeneração natural do local, mas tão importante quanto a decisão sobre métodos de restauração, são as diferenças das comunidades que essas escolhas podem gerar. As FS são heterogêneas e, enquanto existe uma literatura crescente dos fatores que afetam a chance do estabelecimento das FS, poucos trabalhos abordam os fatores que influenciam os atributos dessas florestas. Nesse contexto, nosso trabalho busca identificar as diferenças entre PL e FS e as variáveis locais e de paisagem que afetam os atributos das FS. Para tal, amostramos a comunidade arbórea de florestas estacionais semideciduais de Mata Atlântica estabelecidas naturalmente (FS) e por PL em paisagens agrícolas na bacia do Rio Corumbataí, no estado de São Paulo. Observamos que os PL apresentam biomassa semelhante às SF e maior riqueza de espécies. No entanto, as PL também apresentam menor abundância de indivíduos jovens, indivíduos zoocóricos e lianas. A composição de espécies entre essas florestas também difere. As FS estabelecidas em plantios abandonados de eucalipto apresentaram riqueza de espécies e biomassa de espécies nativas semelhantes a outras florestas secundárias. No entanto, os atributos das SF variam consideravelmente. Nesse contexto, as FS apresentam elevado potencial de provimento de alimento para a fauna e estocagem de carbono de maneira custo-eficiente, enquanto que as PL podem ter sua permanência em longo prazo comprometida pela falta de indivíduos jovens. Em seguida, investigamos as variáveis que direcionam a heterogeneidade observada nas FS utilizando modelos mistos lineares generalizados para estimar a influência de variáveis locais e de paisagem na biomassa, densidade de espécies, área basal de árvores zoocóricas e estrutura filogenética das FS amostradas. Plantios de cana-de-açúcar próximos as FS reduzem a biomassa e área basal de indivíduos zoocóricos, enquanto que a cobertura florestal da paisagem aumentou a densidade de espécies e a diversidade filogenética. A idade da floresta apresentou importância secundária ou nula para os atributos estudados. Nossos resultados ressaltam a importância de práticas agrícolas que minimizem os danos em florestas próximas e de mecanismos que favoreçam a cobertura florestal nativa em paisagens agrícolas, a fim de fomentar o potencial dessas florestas em prover serviços ecossistêmicos e conservar a biodiversidade. A escolha entre facilitação do estabelecimento de FS ou PL visando a restauração florestal está condicionada ao contexto local e de paisagem onde serão realizadas as ações de restauração. Apesar de ambas as abordagens apresentarem potencial para cumprir os objetivos dos projetos de restauração, atenção especial deve ser dada ao recrutamento de novos indivíduos para manter a sustentabilidade de PL, enquanto que práticas agrícolas menos impactantes e paisagens agrícolas com maior cobertura florestal nativa podem aumentar o potencial de SF em prover serviços e conservar a biodiversidade.
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Alexandrino, Eduardo Roberto. "A paisagem antrópica sob avaliação: a avifauna em remanescentes florestais, matrizes agrícolas e as implicações para a conservação." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-19102015-174122/.
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Devido o dinamismo e complexidade estrutural observada nas paisagens antrópicas, pesquisas contínuas são necessárias para melhorar o conhecimento sobre quais os impactos delas na biodiversidade, bem como para entender quais espécies ocorrentes nestas paisagens refletem as condições ambientais lá existentes. Desse modo, tomando a avifauna como representante da biodiversidade presente nestas paisagens, esta tese objetivou: 1) caracterizar as assembleias de aves ocorrentes nos remanescentes florestais de Mata Atlântica inseridos em paisagem antrópica agrícola, bem como as assembleias que ocorrem no interior das culturas de pasto e cana-de-açúcar, 2) identificar um método analítico adequado para acessar a integridade ecológica existente nos remanescentes florestais por meio das assembleias de aves, 3) avaliar o efeito da estrutura e dinâmica destas paisagens nas assembleias de aves ocorrentes nos remanescentes florestais, 4) identificar quais características da paisagem antrópica agrícola influenciam as aves ocorrentes no interior das culturas de pasto e cana-de-açúcar. Assembleias de aves foram amostradas mensalmente durante um ano (Nov2011-Nov2012) por meio de pontos fixos e transectos em oito remanescentes florestais com diferentes tamanhos (3-115ha) e históricos de degradação, e oito sítios amostrais localizados no interior das culturas agrícolas (quatro em pasto e quatro em cana-de-açúcar). Estes foram selecionados dentro de cinco unidades amostrais de uma paisagem tipicamente (16 km2) agrícola do Estado de São Paulo (Bacia do Rio Corumbataí). O índice de serviços ecossistêmicos de Ferraz et al. (2014) foi adotado como uma medida do grau de distúrbios antrópicos presente nos remanescentes florestais do qual leva em consideração a dinâmica e estrutura deles. Já as características das paisagens nas culturas agrícolas foram coletadas em duas escalas de análise (buffers circulares de 600 e 1000m) levando em consideração métricas que pudessem refletir uma maior heterogeneidade da paisagem. No total, 191 espécies foram observadas nos remanescentes florestais, enquanto que 137 nas culturas agrícolas. As aves com hábitos florestais, não-florestais, hábitos mistos florestais-não-florestais, pequenos insetívoros de sub-bosque, aves que forrageiam no estrato médio dos remanescentes, espécies endêmicas e ameaçadas foram os melhores indicadores ecológicos nos remanescentes. Estes grupos formaram a base de dados do Índice de Integridade Biótica (IIB) um método multimétrico que obteve um melhor desempenho em refletir a integridade existente nos remanescentes quando comparado com os níveis de sensibilidade a distúrbios antrópicos de Parker III et al. (1996), riqueza geral das assembleias e índice de diversidade de Shannon. Foram registradas 132 espécies nas pastagens enquanto que apenas 72 nos canaviais, sendo que tanto a riqueza geral quanto a abundância relativa de alguns grupos de aves foram explicadas pela variação na heterogeneidade da paisagem. Assim, conclui-se que métodos analíticos classicamente utilizados em ecologia podem apresentar falhas na avaliação ecológica de remanescentes de Mata Atlântica inseridos em paisagem antrópica, ocasionando interpretações errôneas. Novos métodos analíticos devem ser explorados, sendo o IIB um possível substituto. A diferença existente entre as assembleias de aves ocorrentes nas pastagens, (maior heterogeneidade) e nos canaviais (baixa heterogeneidade) indicam as consequências negativas que homogeneização da paisagem agrícola pode ocasionar à biodiversidade ocorrente nestas paisagens.Because human-modified landscapes (HML) are dynamic and have structural complexity, continuous research is necessary to improve knowledge about the HML impacts on the biodiversity, as well as to provide knowledge of which current species may reflect the environmental conditions existing there. Thus, considering birds as sample of the HML existing biodiversity, the following thesis aimed to: 1) describe the bird assemblages of Atlantic Forest patches located in HML and bird assemblages of the interior of cattle pastures and sugar cane crops, 2) identify a proper bird analytical approach to assess the existing ecological integrity of forest patches in HML, 3) assess the effects of the landscape features (dynamic and structure) on the bird assemblages of forest patches in HML, 4) identify which landscapes features of both crops may exert influence on the bird assemblage composition of each crop. Bird sampling was performed monthly along one year (Nov 2011 - Nov 2012) in eight forest patches with different historical and size (3 - 115 ha), and eight sites located in the interior of each crop (four in cattle pasture and four in sugar cane), using point counts and transects. Five focal landscapes (16 km2) located in a typical HML of São Paulo state (Corumbataí river basin) were used to select these sampling sites. The rank of ecosystem services provisioning of Ferraz et al. (2014) was used as a measurement of the existing gradient of human disturbance in the forest patches, which was built through information about forest dynamic and structure. The landscape features of each crop were collected through two scale of analysis (circular buffers with 600 and 1000 radius meters) taking into account metrics that may represent the landscape heterogeneity. 191 species were observed in the forest patches while 137 in the crops. The forest birds, non-forest birds, birds with forest-non-forest habits, small understory-midstory insectivorous, species with foraging habits in the midstory strata, threatened and endemic species, were the best ecological indicators of the forest patches. These bird groups were used as database in the development of the Index of Biotic Integrity (IBI), a multimetric approach, which showed a better performance to indicate the existent integrity in the forest patches in comparison with \"sensitivity to disturbance\" of Parker III et al. (1996), total species richness and Shannon´s diversity index. 132 species were observed in cattle pastures while 72 in sugar cane. Both richness and relative abundance of some bird groups were explained by the landscape heterogeneity variation. Thus, it is possible to conclude that some classical birds analytical approaches may be flawed in the ecological assessment of Atlantic Forest patches inserted in HML. New analytical approaches should be explored, and the IBI is a possible alternative. The bird\'s assemblage differences between cattle pastures (high heterogeneity) and sugar cane (low heterogeneity) are an example of the negative consequences caused by the crops homogenization on the living biodiversity of agricultural landscapes.
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Burcsu, Theresa Katherine. "Forest edges effects on vegetation, environmental gradients and local avian communities in the Sierra Juarez, Oaxaca, Mexico /." [Bloomington, Ind.] : Indiana University, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3232575.
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Thesis (Ph.D.)--Indiana University, School of Public and Environmental Affairs, 2006."Title from dissertation home page (viewed July 11, 2007)." Source: Dissertation Abstracts International, Volume: 67-08, Section: B, page: 4319. Adviser: Vicky J. Meretsky.
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Villard, Marc-Andre Carleton University Dissertation Biology. "Spatio-temporal dynamics of forest bird patch populations in agricultural landscapes." Ottawa, 1991.
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Liu, Yan. "The economics of forest carbon offset trading: the design of an economic experiment." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40740.
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The proposed Domestic Emission Trading System in Canada included an offset market that was expected to provide cost-efficient carbon offsets to the Large Final Emitters. The objective of this thesis was to design an economic experiment that incorporated this institutional design. The experimental design included both regulated and non-regulated sectors and is based on a “cap and trade” carbon emission model. Three markets are included in the experimental design: timber, carbon, and electricity. The electricity sector represents the regulated sectors with a carbon emission cap while the forestry sector represents the non-regulated sectors, i.e. they do not have a carbon emission cap. The decision making framework of the forestry sector is based on a joint-product model; i.e. timber and carbon. The price of carbon offset credits impacts both timber and electricity supply.Le système d’échange de droits d’émission envisagé au Canada incluait un marché compensatoire qui devait fournir aux grands émetteurs finaux des crédits compensatoires pour le carbone rentables. L'objectif de cette thèse était de concevoir une expérience économique qui incluait cette conception institutionnelle. L'expérience a été conçue pour inclure des marchés réglementés et non-réglementés et elle est basée sur un modèle “cap and trade” d’échange d’émissions de carbone. Elle a été menée sur trois marchés : celui du bois, celui du carbone et celui de l’électricité. Le marché de l’électricité représente les marchés réglementés avec un cap sur émissions de carbone tandis que le secteur forestier représente les marchés non-réglementés, c.-à-d. il n’y a pas de cap sur émissions de carbone. Les décisions de production dans le secteur forestier sont basées sur un modèle de production conjoint ; c.-à-d. celui du bois et du carbone. Le prix des crédits compensatoires pour le carbone ont une influence sur l’offre de bois et d’électricité. La réglementation de l’émission du carbone est incorporée dans l’expérience en utilisant une courbe de l’offre coudée pour l’électricité. Les prévisions de la théorie et du comportement ont été faites en se basant sur les incitatifs proposés dans l’expérience ainsi que sur l’expérience d’expériences antérieures.
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Bellantoni, Elizabeth Susan 1958. "Habitat use by desert mule deer and collared peccary in an urban environment." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277936.
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I examined movements and habitat use by desert mule deer (Odocoileus hemionus crooki) and collared peccary (Dicotyles tajacu) in the Rincon Mountain District of Saguaro National Monument (SNM) from February 1988 through December 1989. Movements and habitat use by mule deer were closely associated with the distribution of free-standing water during the driest seasons of the year. Deer responded to losses of ephemeral water sources in SNM by leaving the monument to obtain water. Four of 5 peccary herds supplemented their natural diet by visiting houses and/or restaurants on a daily or twice daily basis. The addition of water and supplemental food sources was a deliberate effort by homeowners to attract wildlife onto their property. The current pattern of habitat islands interspersed with low density housing (1 house/2-4 ha) is an effective and highly desirable buffer zone between the monument and the more heavily developed urban areas 3.2 km west of the park.
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Banki, Ahmad. "Insurance purchasing under ambiguity, and its applications for forest carbon offsets: an experimental study." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=97116.
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The limitations of the expected utility theory in predicting risk preference under low probabilities have been discussed by various experimental studies. However, the ex-isting studies have not arrived at a consensus in this area. There are signs of both over-insurance and under-insurance for low-probability loss events. The topic has particularly not been addressed when ambiguity is coupled with low probability estimates. This paper theoretically analyzes the implications of ambiguity aversion for insurance purchasing in loss events involving low probabilities. The topic has been looked into under the light of forest carbon offsets and the need for insurance for unavoidable losses of the sequestrated carbon. The paper offers an experimental design involving three phases, including a replica of a previous study on insurance behaviour, addition of the ambiguity factor, and two methods of measuring ambiguity preference. Wildfire losses are associated with small probabilities and ambiguity, and ambiguity increases the individual's willingness to pay for insurance. Therefore, the government can set a higher price for its mandatory insurance program provided on forestry offset credits.Les limites sur la théorie de l'utilité anticipée utilisée pour prédire les préférences de risque sous de faibles probabilités ont été discutées dans plusieurs études expérimenta-les. Toutefois, les études existantes n'en sont pas arrivées à un consensus. Il y a des si-gnaux tant pour une confiance élevée que basse dans des situations de faibles probabilités de pertes. Le sujet n'a pas été particulièrement questionné lorsque l'ambigüité est combi-née avec des estimations de faibles probabilités. Cette étude analyse théoriquement les implications de l'aversion de l'ambigüité lors de l'achat d'assurance dans un contexte de situations comprenant de faibles probabilités de perte. Cette étude examine les crédits de carbone au niveau forestier ainsi qu'aux besoins d'assurances afin d'éliminer d'inévitables pertes reliées aux séquestrations de carbone. Cette étude offre un design expérimental comprenant trois phases, incluant une réplique des études existantes sur les comportements des consommateurs d'assurances, ajoutant le facteur d'ambigüité ainsi que deux méthodes de mesures pour les préférences d'ambigüité.
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Belmont, Jonathon. "The study of carbon and nutrients in forests : a foundation for examining global change /." [Bloomington, Ind.] : Indiana University, 2004. http://wwwlib.umi.com/dissertations/fullcit/3162225.
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Thesis (Ph.D.)--Indiana University, School of Public and Environmental Affairs, 2004.Title from PDF t.p. (viewed Dec. 1, 2008). Source: Dissertation Abstracts International, Volume: 66-01, Section: B, page: 0177. Chair: J. C. Randolph.
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Sarlöv, Herlin Ingrid. "Edge habitats in agricultural landscapes : woody species, landscape ecology and implications for planning /." Alnarp : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5715-7.pdf.
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Renoirt, Matthias. "Influence de l’habitat sur l’écologie et la physiologie du crapaud épineux (Bufo spinosus)." Electronic Thesis or Diss., La Rochelle, 2022. http://www.theses.fr/2022LAROS041.
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Un grand nombre d’études ont mis en avant les effets négatifs des pressions anthropiques dans le temps et dans l’espace sur la biodiversité. Parmi ces pressions anthropiques, les activités et l’expansion agricole jouent un rôle principal dans la modification des milieux et dans la perte de biodiversité. De fait, la question de la persistance des espèces animales dans ce type de milieux se pose. C’est dans ce contexte que ma thèse s’axe. Afin d’étudier les réponses des organismes à un milieu dégradé et les contraintes du paysage sur différents traits d’histoire de vie et l’écologie, je travaille spécifiquement sur une espèce d’amphibien occupant des milieux allant de fortement conservés à fortement dégradés. Afin de comparer les populations de crapauds épineux (Bufo spinosus) forestières et les populations agricoles, j’utilise un vaste panel de marqueurs pour examiner (1) la structure génétique des populations (marqueurs microsatellites), (2) l’écologie alimentaire (isotopes stables), (3) la qualité individuelle (télomères, morphologie, traits de développement) et son impact sur la reproduction. De ce fait et au cours de cette thèse, j’ai pu mettre en relation de nombreux facteurs associés aux paysages agricoles qui soulèvent de nombreuses questions quant au maintien des populations de crapauds épineux. Ainsi, nous avons pu montrer un effet significatif des fertilisants sur la signature isotopique en δ15N des populations de B.spinosus. Aussi, nous avons pu souligner que l’environnement agricole reste suffisamment perméable au maintien de la diversité génétique. Cependant, nous avons mis en évidence de nombreuses contraintes de ce milieu sur la reproduction des populations d’amphibiens, que ce soit par la faible (voir l’absence) abondance de femelles sur les sites de reproduction, et/ou directement sur le succès reproducteur et la qualité de la progéniture. Ces résultats suggèrent de possibles effets à long terme sur les populations d’amphibiens et nous suggérons d’approfondir les différentes voies de recherche que nous suggérons tout au long de cette thèse afin de mieux comprendre les mécanismes sous-jacents à ces résultats et de trouver des solutions quant à la pérennité des espèces sauvages qui n’ont d’autres choix que de s’adapterA large number of studies have highlighted the negative effects of anthropogenic pressures intime and space on biodiversity. Among these anthropogenic pressures, agricultural activities and expansion play a major role in the modification of environments and in the loss of biodiversity. Questions whether animal species persist in this type of environment arises. My thesis is based on this context. We aimed at study the responses of organism to a degraded environment and the landscape constraints on life history traits and ecology. My work is focused specifically on an amphibian species persisting in habitat ranging from highly conserved to highly degraded by agricultural activities. In order to compare forest and agricultural populations of model species (Spined toad, Bufo spinosus), I relied on a wide variety of markers to examine (1) population genetic structure (micro-satellite markers), (2) feeding ecology (stable isotope), (3) individual quality (telomeres, morphology, developmental traits) and the impact on reproduction. As a result, I was able to connect many factors associated with agricultural landscapes that raised many questions about the persistence of spined toad populations. We were able to show a significant effect of fertilizers on the δ15N isotopic signature of B.spinosus populations. Moreover, we highlighted that agricultural environment allows genetic diversity between populations. However, using correlative approaches, we pointed out various on strains of this environment on the reproduction of amphibians populations, either through low (or no) abundance of females on breeding sites, and/or directly on reproductive success and offspring quality. These results suggest possible long-term effects on amphibian populations, and we suggest that the various avenues of research we suggested throughout this thesis should be pursued in order to better understand the mechanisms underlying these results and to find solutions for the sustainability of wild species that have no choice but to adapt
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Jagger, Pamela. "Can forest sector devolution improve rural livelihoods? an analysis of forest income and institutions in western Uganda /." [Bloomington, Ind.] : Indiana University, 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3358922.
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Thesis (Ph.D.)--Indiana University, Dept of Public and Environmental Affairs and the Dept. of Political Science, 2009.Title from PDF t.p. (viewed on Feb. 8, 2010). Source: Dissertation Abstracts International, Volume: 70-05, Section: A, page: 1775. Adviser: Elinor Ostrom.
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Fenni, Ines. "Efficient domain decomposition methods for electromagnetic modeling of scattering from forest environments." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066264/document.
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Cette thèse porte sur la modélisation et l’analyse de la propagation électromagnétique dans un milieu forestier dans les bandes VHF et UHF. L’objectif principal est le développement d’un modèle numérique "full-wave" tridimensionnel de diffusion par la forêt permettant de caractériser l’interaction d’une onde électromagnétique avec un milieu forestier. Un tel modèle s’avère, actuellement, un outil indispensable à l’analyse des mesures radar pour l’étude des paramètres caractéristiques de la forêt tels que la biomasse forestière, la hauteur des arbres et leur densité. La complexité numérique de ce modèle a limité son domaine d’application à de petites parcelles de forêt et aux basses fréquences. Pour pouvoir traiter de larges zones forestières tout en montant en fréquence, et s’approcher ainsi des besoins et exigences des utilisateurs potentiels de notre modèle, nous avons intégré à ce modèle une méthode numérique efficace dédiée à l’analyse de larges problèmes électromagnétiques. La méthode en question,connue sous le nom de Characteristic Basis Function Method (CBFM) était récemment développée dans le laboratoire de Communication et Electromagnétisme de l’université PennState dirigé par le Professeur Mittra. Après une optimisation et une adaptation au problème d’intérêt, la CBFM réalise d’excellentes performances et nous permet une diminution considérable du temps de calcul et des besoins en espace mémoire sans pour autant dégrader la qualité des résultats obtenus ou altérer la fidélité du modèle à la réalité du problème électromagnétique traitéA 3-D full-wave model, based on the integral representation of the electric field and dedicatedto the analysis of bi-static scattering mechanisms by a forest in the VHF and UHF bands wasefficiently enhanced. In order to overcome the limitation of a previous 3D model to small simulationsscenes and low frequencies, we have developed, during this research work, a new model using basis functionsadapted to the problem of interest, in the context of the Characteristic Basis Function Method(CBFM) and we investigated the suitability of this direct method for computing the electromagneticfields inside and outside three-dimensional dielectric objects representing the tree trunks and branches.The CBFM has shown great performances, when applied to the forest scattering modeling, both interms of CPU time and memory resources needed. Once properly set, the CBFM-E is so efficient thatit is able to treat in few minutes electromagnetic problems totally intractable with the classical MoM.Consequently, we have developed a powerful 3D forest electromagnetic scattering tool which allows ustoday to compute large forest electromagnetic problems in few minutes without worrying about theaccuracy of the solution. On the other hand, we have demonstrated the efficiency and accuracy of theCBFM-E when applied to 3D dielectric objects in the context of the electric volumetric integral equation,and have consolidated thus its leading position in the computational electromagnetics, especiallyagainst the iterative solvers based numerical methods
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Bailey, Jennifer Meghan. "Western Spruce Budworm Effects on Throughfall C, N, and P Fluxes in a Central Washington Forest." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc955099/.
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Western spruce budworm (Choristoneura occidentalis) outbreaks periodically disturb Western US conifer forests by defoliating canopies, which could alter the quantity and chemistry of throughfall delivered to the forest floor. Our objectives were to: i) quantify throughfall water, carbon (C), nitrogen (N), and phosphorus (P) fluxes under budworm-impacted canopies, and ii) examine the influence of herbivore intensity on flux magnitudes. In June 2015, we installed throughfall collectors in two watersheds experiencing high and background levels of herbivory. In each watershed, four plots, each with three throughfall collectors, were established (n=24) collectors), and two bulk rainfall collectors were installed in areas without canopy cover. Throughfall and rainfall were collected from late June to early November 2015. Samples were analyzed for dissolved organic carbon (DOC), ammonium (NH4-N), and soluble reactive phosphorus (SRP). Over the sampling period, throughfall fluxes ranged 8.57 to 47.59 kg/ha for DOC, 0.004-0.011 kg/ha for NH4-N, and 007 - 0.29 kg/ha for SRP. Percent throughfall was slightly, but not significantly, higher in the high (48%) compared to the background watershed (42%). There were no differences in solute concentrations among the watersheds. Net throughfall fluxes, the sum of canopy uptake and leaching and dry/fog deposition, differed significantly for NH4-N by herbivory level and through time for NH4-N and DOC but not SRP. Over time, net NH4-N throughfall fluxes showed a clear transition from net uptake of NH4-N to net leaching of NH4-N in the high herbivory watershed. There was also a clearn NH4-N pulse in the high herbivory watershed after the first, but not subsequent, rainfall events. In this N-limited forest, altered throughfall N may affect soil nutrient cycling and downstream water quality.