13 resultados para landscape compensation

em Helda - Digital Repository of University of Helsinki


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Sichuanissa Tiibetin ylängön metsäkato on pysähtynyt mutta eroosio-ongelmat jatkuvat Viikin tropiikki-instituutin tutkija Ping ZHOU kartoitti trooppisen metsänhoidon alaan kuuluvassa väitöskirjatyössään maaperän eroosioalttiutta ja sen riippuvuutta metsäkasvillisuudesta Jangtsen tärkeää sivuhaaraa Min-jokea ympäröivällä n. 7400 neliökilometrin suuruisella valuma-alueella Sichuanin Aba-piirikunnassa. Aineistonaan hän käytti muun muassa satelliittikartoitustietoja ja mittaustuloksia yli 600 maastokoealalta. Tutkimuksen nimi suomeksi on "Maaperän eroosion mallinnus ja vuoristoisen valuma-alueen ekologinen ennallistaminen Sichuanissa Kiinassa". Aikaisempien tutkimusten perusteella oli tiedossa että metsien häviäminen tällä alueella pysähtyi jo 1980-luvun alussa. Sen jälkeen on metsien pinta-ala hitaasti kasvanut etupäässä sen vuoksi, että teollinen puunhakkuu luonnonmetsissä kiellettiin kokonaan v. 1998 ja 25 astetta jyrkemmillä rinteillä myös maatalouden harjoittaminen on saatu lopetetuksi viljelijöille tarjottujen taloudellisten houkuttimien avulla. Täten myös pelto- ja laidunmaata on voitu ennallistaa metsäksi. Ping Zhou pystyi jakamaan 5700 metrin korkeuteen saakka kohoavan vuoristoalueen eroosioalttiudeltaan erilaisiin vyöhykkeisiin rinteen kaltevuuden, sademäärän, kasvipeitteen ja maalajin perusteella. Noin 15 prosentilla tutkitun valuma-alueen pinta-alasta, lähinnä Min-joen pääuomaa ympäröivillä jyrkillä rinteillä, eroosioriski oli suuri tai erittäin suuri. Eri tyyppisellä kasvillisuudella oli hyvin erilainen vaikutus eroosioalttiuteen, ja myös alueen sijainti vuoriston eri korkeuksilla vaikutti eroosioon. Säästyneet lähes luonnontilaiset havumetsät, joita on etupäässä vuoriston ylimmissä osissa 2600-4000 metrin korkeudella, edistävät tehokkaasti metsän luontaista uudistumista ja levittäytymistä vaurioituneille alueille. Säilyneiden metsien puulajikoostumus antoi tutkimuksessa mahdollisuuden ennustaa metsien tulevaa kehitystä koko tutkitulla valuma-alueella sen eri korkeusvyöhykkeissä ja eri maaperätyypeillä. Ennallistamisen kannalta ongelmallisimpia olivat alueet joilta metsäpeite oli lähinnä puiden teollisen hakkuun vuoksi kokonaan hävinnyt ja joilla maaperä yleisesti oli eroosion pahoin kuluttama. Näillä alueilla ei ole tehty juuri mitään uudistamis- tai ennallistamistoimenpiteitä. Niillä metsien ennallistaminen vaatii myös puiden tai pensaiden istuttamista. Tähän sopivia ovat erityisesti ilmakehän typpeä sitovat lajit, joista alueella kasvaa luontaisena mm. sama tyrnilaji joka esiintyy myös Suomessa. Työssä tutkittiin yli kahdeksankymmenen paikallisen luontaisen puulajin (joista peräti noin kolmannes on havupuulajeja) ekologisia ominaisuuksia ja soveltuvuutta metsien ennallistamiseen. Avainasemassa työn onnistumisen kannalta ovat nyt paikalliset asukkaat, joiden maankäytön muutokset ovat jo selvästi edistänet luonnonmetsän ennalleen palautumista. Suomen Akatemia rahoitti vuosina 2004-2006 VITRI:n tutkimushanketta, josta Ping Zhou'n väitöskirjatyö muodosti keskeisen osan. Kenttätyö Sichuanissa avasi mahdollisuuden hedelmälliseen monitieteiseen yhteistyöhön ja tutkijavaihtoon Kiinan tiedeakatemian alaisen Chengdun biologiainstituutin (CIB) kanssa; tämä tieteellinen kanssakäyminen jatkuu edelleen.

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The object of this study was to find out which factors made landowners interested in From Sea to Forest co-operation network. Co-operation networks protect biodiversity across boundaries and among groups of landowners with different kind of protection contracts. The social effects of From Sea to Forest - project are studied by analyzing the experience of co-operation and trust. Furthermore the possibility to influence decision making when choosing the pilot areas and doing the contracts was surveyed. Economical effects are estimated for those landowners, who signed a protection contract for ten years. The study is part of The Finnish Forest Research Institute s Ecological considerations in landscape-level collaborative planning of private forestry project. The material of the study comprises 13 interviews done in January 2006; seven interviewed were landowners and six forest professionals. The interviews were transcripted and analyzed with Atlas.ti programme. The economical effects were estimated with MOTTI forest simulation programme. From Sea to Forest project interested the landowners for similar reasons: the voluntariness of participation, compensation, fixed-term contracts and the possibility to protect forests so that the proprietary right remains. It was possible to form four different groups of interviewed landowners according to trust: networkers , opportunists , carefuls and selfemployed . Only in the group of opportunists the project created so much trust that a significant increase of interest to participate in the project was noticed. In all the other groups the project didn t create remarkable trust, so trust didn t have an effect on landowners decisions to participate. Other factors, like compensation and voluntariness were decisive for their interest to participate. From Sea to Forest project wasn t a network based on landowners co-operation, the communication was directly with the project worker. The effects on landowners income by signing a ten year ´Natural value trading´ -contract was analyzed by comparing the protection income with predicted forestry income in case that the protection contract wouldn t have been agreed on. For two landowners there was no suggested forestry work within ten years, so their protection income might be an additional income, if they decided to log their forests later. For three landowners delayed thinning of the sapling stand would cause income losses in the future, if they decided to move to active forestry after ten years of protection. For eight landowners the effect of protection is positive to income if they moved to active forestry after the ten years protection period. This occurred, because the tree stand is now mature for final felling on behalf of its age, but ten more years of growth increase the net present value. Longer term protection might diminish the net present value. The protection was profitable because hectare specific forestry income grew compared to forestry cutting plan income.

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Intensified agricultural practises introduced after the Second World War are identified as a major cause of global biodiversity declines. In several European countries agri-environment support schemes have been introduced to counteract the ongoing biodiversity declines. Farmers participating in agri-environment schemes are financially compensated for decreasing the intensity of farming practises leading to smaller yields and lower income. The Finnish agri-environment support scheme is composed of a set of measures, such as widened field margins along main ditches (obligatory measure), management of features increasing landscape diversity, management of semi-natural grasslands, and organic farming (special agreement measures). The magnitude of the benefits for biodiversity depends on landscape context and the properties of individual schemes. In this thesis I studied whether one agri-environment scheme, organic farming, is beneficial for species diversity and abundance of diurnal lepidopterans, bumblebees, carabid beetles and arable weeds. I found that organic farming did not enhance species richness of selected insect taxa, although bumblebee species richness tended to be higher in organic farms. Abundance of lepidopterans and bumblebees was not enhanced by organic farming, but carabid beetle abundance was higher in mixed farms with both cereal crop production and animal husbandry. Both species richness and abundance of arable weeds were higher in organic farms. My second objective was to study how landscape structure shapes farmland butterfly communities. I found that the percentage of habitat specialists and species with poor dispersal abilities in butterfly assemblages decreased with increasing arable field cover, leading to a dramatic decrease in butterfly beta diversity. In field boundaries local species richness of butterflies was linearly related to landscape species richness in geographic regions with high arable field cover, indicating that butterfly species richness in field boundaries is more limited by landscape factors than local habitat factors. In study landscapes containing semi-natural grasslands the relationship decelerated at high landscape species richness, suggesting that local species richness of butterflies in field boundaries is limited by habitat factors (demanding habitat specialists that occurred in semi-natural grasslands were absent in field margins). My results suggest that management options in field margins will affect mainly generalists, and species with good dispersal abilities, in landscapes with high arable field cover. Habitat specialists and species with poor dispersal abilities may benefit of management options if these are applied in the vicinity of source populations.

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Regeneration ecology, diversity of native woody species and its potential for landscape restoration was studied in the remnant natural forest at the College of Forestry and Natural Resources at Wondo Genet, Ethiopia. The type of forest is Afromontane rainforest , with many valuable tree species like Aningeria adolfi-friederici, and it is an important provider of ecological, social and economical services for the population that lives in this area. The study contains two parts, natural regeneration studies (at the natural forest) and interviews with farmers in the nearby village of the remnant patch. The objective of the first part was to investigate the floristic composition, densitiy and regeneration profiles of native woody species in the forest, paying special attention to woody species that are considered the most relevant (socio-economic). The second part provided information on woody species preferred by the farmers and on multiple uses of the adjacent natural forest, it also provided information and analysed perceptions on forest degradation. Systematic plot sampling was used in the forest inventory. Twenty square plots of 20 x 20 m were assessed, with 38 identified woody species (the total number of species was 45), representing 26 families. Of these species 61% were trees, 13% shrubs, 11% lianas and 16% species that could have both life forms. An analysis of natural regeneration of five important tree species in the natural forest showed that Aningeria adolfi-friederici had the best regeneration results. An analysis of population structure (as determined by height classes) of two commercially important woody species in the forest, Aningeria adolfi-friederici and Podocarpus falcatus, showed a marked difference: Aningeria had a typical “reversed J” frequency distribution, while Podocarpus showed very low values in all height classes. Multi dimensional scaling (MDS) was used to map the sample plots according to their similarity in species composition, using the Sørensen quantitative index, coupled with indicator species analysis .Three groups were identified with respective indicator species: Group 1 – Adhatoda schimperiana, Group 2 – Olea hochstetteri , Group 3 – Acacia senegal and Aningeria adolfi-friederici. Thirty questionnaire interviews were conducted with farmers in the village of Gotu Onoma that use the nearby remant forest patch. Their tree preferences were exotic species such as Eucalyptus globulus for construction and fuelwood and Grevillea robusta for shade and fertility. Considering forest land degradation farmers were aware of the problem and suggested that the governmental institutions address the problem by planting more Eucalyptus globulus. The natural forest seemed to have moderate levels of disturbance and it was still floristically diverse. However, the low rate of natural regeneration of Podocarpus falcatus suggested that this species is threatened and must be a priority in conservation actions. Plantations and agroforestry seem to be possible solutions for rehabilitation of the surrounding degraded lands, thereby decreasing the existent pressure in the remnant natural forest.

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Managerial pay-for-performance sensitivity has increased rapidly around the world. Early empirical research showed that pay-for-performance sensitivity resulting from stock ownership and stock options appeared to be quite low during the 1970s and early 1980s in the U.S. However, recent empirical research from the U.S. shows an enormous increase in pay-for-performance sensitivity. The global trend has also reached Finland, where stock options have become a major ingredient of executive compensation. The fact that stock options seem to be an appealing form of remuneration from a theoretical point of view combined with the observation that the use of this compensation form has increased significantly during the recent years, implies that research on the dynamics of stock option compensation is highly relevant for the academic community, as well as for practitioners and regulators. The research questions of the thesis are analyzed in four separate essays. The first essay examines whether stock option compensation practices of Finnish firms are consistent with predictions from principal-agent theory. The second essay explores one of the major puzzles in the compensation literature by studying determinants of stock option contract design. In theory, optimal contract design should vary according to firm characteristics. However, in the U.S., variation in contract design seems to be surprisingly low, a phenomenon generally attributed to tax and accounting considerations. In Finland, however, firms are not subject to stringent contracting restrictions, and the variation in contract design tends, in fact, to be quite substantial. The third essay studies the impact of price- and risk incentives arising from stock option compensation on firm investment. In addition, the essay explores one of the most debated questions in the literature, in particular, the relation between incentives and firm performance. Finally, several strands of literature in both economics and corporate finance hypothesize that economic uncertainty is related to corporate decision-making. Previous research has shown that risk tends to slow down firm investment. In the fourth essay, it is hypothesized that firm risk slows down growth from a more universal perspective. Consistent with this view, it is shown that risk not only tends to slow down firm investment, but also employment growth. Moreover, the essay explores whether the nature of firms’ compensation policies, in particular, whether firms make use of stock option compensation, affects the relation between risk and firm growth. In summary, the four essays contribute to the current understanding of stock options as a form of equity incentives, and how incentives and risk affect corporate decision-making. By this, the thesis promotes the knowledge related to the modern theory of the firm.

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This paper addresses several questions in the compensation literature by examining stock option compensation practices of Finnish firms. First, the results indicate that principal-agent theory succeeds quite well in predicting the use of stock options. Proxies for monitoring costs, growth opportunities, ownership structure, and risk are found to determine the use of incentives consistent with theory. Furthermore, the paper examines whether determinants of stock options targeted to top management differ from determinants of broad-based stock option plans. Some evidence is found that factors driving these two types of incentives differ. Second, the results reveal that systematic risk significantly increases the likelihood that firms adopt stock option plans, whereas total firm risk and unsystematic risk do not seem to affect this decision. Third, the results show that growth opportunities are related to time-dimensional contracting frequency, consistent with the argument that incentive levels deviate more rapidly from optimum in firms with high growth opportunities. Finally, the results suggest that vesting schedules are decreasing in financial leverage, and that contract maturity is decreasing in firm focus. In addition, both vesting schedules and contract maturity tend to be longer in firms involving state ownership.

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We present a laser-based system to measure the refractive index of air over a long path length. In optical distance measurements it is essential to know the refractive index of air with high accuracy. Commonly, the refractive index of air is calculated from the properties of the ambient air using either Ciddor or Edlén equations, where the dominant uncertainty component is in most cases the air temperature. The method developed in this work utilises direct absorption spectroscopy of oxygen to measure the average temperature of air and of water vapor to measure relative humidity. The method allows measurement of temperature and humidity over the same beam path as in optical distance measurement, providing spatially well matching data. Indoor and outdoor measurements demonstrate the effectiveness of the method. In particular, we demonstrate an effective compensation of the refractive index of air in an interferometric length measurement at a time-variant and spatially non-homogenous temperature over a long time period. Further, we were able to demonstrate 7 mK RMS noise over a 67 m path length using 120 s sample time. To our knowledge, this is the best temperature precision reported for a spectroscopic temperature measurement.