4 resultados para Resilient

em Helda - Digital Repository of University of Helsinki


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The impacts of fragmentation and recreational use on the hemiboreal urban forest understorey vegetation and the microbial community of the humus layer (the phospholipid fatty acid (PLFA) pattern, microbial biomass and microbial activity, measured as basal respiration) were examined in the greater Helsinki area, southern Finland. Trampling tolerance of 1) herb-rich OMT, 2) mesic MT, and 3) sub-xeric VT forests (in decreasing order of fertility) was studied by comparing relative understorey vegetation cover (urban/untrampled reference ratio) of the three forest types. The trampling tolerance of forest vegetation increased with the productivity of the site (sub-xeric < mesic < herb-rich). Wear of understorey vegetation correlated positively with the number of residents (i.e., recreational pressure) around the forest patch. An increase of 15000 residents within a radius of 1 km around a forest patch was associated with ca. 30% decrease in the relative understorey vegetation cover. The cover of dwarf shrub Vaccinium myrtillus in particular decreased with increasing levels of wear. The cover of mosses in urban forests was less than half of that in untrampled reference areas. Cover of tree saplings, mainly Sorbus aucuparia, and some resilient herbs was higher than in the reference areas. In small urban forest fragments, broad-leaved trees, grasses and herbs were more abundant and mosses were scarcer than in larger urban forest areas. Thus, due to trampling and edge effects, resilient herb and grass species are replacing sensitive dwarf shrubs, mosses and lichens in urban forests. Differences in the soil microbial community structure were found between paths and untrampled areas and the effects of paths extended more than one meter from the paths. Paths supported approximately 25-30% higher microbial biomass with a transition zone of at least 1 m from the path edge. However, microbial activity per unit of biomass was lower on paths than in untrampled areas. Furthermore, microbial biomass and activity were 30-45% lower at the first 20 m into the forest fragments, due to low moisture content of humus near the edge. The decreased microbial activity detected at forest edges and paths implies decreased litter decomposition rates, and thus, a change in nutrient cycling. Changes in the decomposition and nutrient supply may in turn affect the diversity and function of plant communities in urban forests. Keywords: boreal forest vegetation, edge effects, phospholipid fatty acids, trampling, urban woodlands, wear

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Infertility treatments are relatively easily available in most Western countries today, but the psychological consequences of these high-tech treatments have scarcely been addressed. The purpose of this controlled longitudinal study was to explore the early environment of the infant born by assisted reproductive treatment (ART). We focused on the parents mental well-being, marital relations and experience of parenting. In addition to this, we assessed parent child interaction and parents mental representations of their child after long-standing infertility and several unsuccessful ART attempts. The subjects were infertile couples who achieved a singleton pregnancy by in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI). The control group comprised of spontaneously conceiving couples with singleton pregnancies. ART women showed fewer depressive symptoms than controls during pregnancy and after delivery, but the difference vanished by the end of the child s first year. ART men consistently had lower levels of anxiety symptoms, sleeping difficulties, and social dysfunction than control men. Control women experienced a decrease in dyadic consensus during the child s first year, which did not happen among ART women. After the child was born, ART men reported a higher level of sexual affection compared with control men. Psychic symptoms and stressful life events were differently related to marital relations in ART and control groups. The parenting experiences of ART mothers were in general at a higher level, compared with controls, and they changed in a positive direction during the child s first year. Fathering experiences were at the same level in both groups, and they changed positively in both groups by the end of the child s first year. The parenting experiences of ART mothers and fathers were more resilient to certain child-related stressors than those of control group. Both mothers and fathers with long-term infertility showed more sensitive behaviour with their child in toddler-age than in infancy. Correspondingly, children s cooperation increased. Mothers often mentioned a fear of miscarriage and difficulty in creating representations of the child during pregnancy. Descriptions of the infants were mainly rich, vivid and loaded with positive features. In conclusion, ART parents in general seem to adapt well to the transition to parenthood. Former infertility and ART do not seem to constitute a risk for parents mental health, marital relations or experience of parenting. Even longstanding infertility with several unsuccessful treatment attempts did not create a risk as regards parenting behaviour or parents mental representations of their child. In this group, however, women were found to have fear for losing the child and difficulty in creating representations of the child during pregnancy, which in some cases may indicate need for psychosocial support. Even though our results are encouraging, infertility and infertility treatments are generally considered as a stressful experience. It is a challenge for health authorities to recognize those couples who need professional help to overcome the distressing experiences of infertility and ART.

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This dissertation concerns the Punan Vuhang, former hunter-gatherers who are now part-time farmers living in an area of remote rainforest in the Malaysian state of Sarawak. It covers two themes: first, examining their methods of securing a livelihood in the rainforest, and second looking at their adaptation to a settled life and agriculture, and their response to rapid and large-scale commercial logging. This study engages the long-running debates among anthropologists and ecologists on whether recent hunting-gathering societies were able to survive in the tropical rainforest without dependence on farming societies for food resources. In the search for evidence, the study poses three questions: What food resources were available to rainforest hunter-gatherers? How did they hunt and gather these foods? How did they cope with periodic food shortages? In fashioning a life in the rainforest, the Punan Vuhang survived resource scarcity by developing adaptive strategies through intensive use of their knowledge of the forest and its resources. They also adopted social practices such as sharing and reciprocity, and resource tenure to sustain themselves without recourse to external sources of food. In the 1960s, the Punan Vuhang settled down in response to external influences arising in part from the Indonesian-Malaysian Confrontation. This, in turn, initiated a series of processes with political, economic and religious implications. However, elements of the traditional economy have remained resilient as the people continue to hunt, fish and gather, and are able to farm on an individual basis, unlike neighboring shifting cultivators who need to cooperate with each other. At the beginning of the 21st century, the Punan Vuhang face a new challenge arising from the issue of rights in the context of the state and national law and large-scale commercial logging in their forest habitat. The future seems bleak as they face the social problems of alcoholism, declining leadership, and dependence on cash income and commodities from the market.

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Soilla on merkittävä rooli ilmastonmuutoksen hillitsemisessä suuren hiilivarastonsa sekä ekosysteemin ja ilmakehän välisen kaasunvaihdon ansiosta. Ilmastonmuutoksen ennustetaan vaikuttavan suokasvillisuuteen ja suon toimintaan epäsuorasti. Vedenpinnan ennustetaan laskevan 14–21 cm johtuen kasveista ja avoimilta pinnoilta tapahtuvan haihdunnan lisääntymisestä lämpötilan noustessa, mikäli sadanta ei lisäänny. Aiemmat vedenpinnan laskun jälkeistä kasvillisuutta seuranneet tutkimukset ovat osoittaneet, että putkilokasvit hyötyvät alhaisemmasta vedenpinnan tasosta ja että kuljuun sopeutuneet rahkasammalet kärsivät kuivuneista oloista. Kasvillisuuden runsaussuhteiden muuttumisen lisäksi kasviyhteisöjen monimuotoisuus vähenee. Erityisen herkkiä vedenpinnan laskulle ovat olleet välipinta- ja kuljurahkasammalet ja sarat. Funktionaalisten kasviryhmien vasteiden selvittämiksesi käytettiin BACI (before-after-control-impact) –tutkimusotetta. Tutkimuksessa oli kolme verrokkialaa ja kolme käsittelyalaa, joissa vedenpintaa oli laskettu 14–21 senttimetriin. Lisäksi vertailukohdaksi tutkimuksessa oli mukana kolme alaa, joissa oli tehty metsäojitus n. 50 vuotta sitten. Nämä toistot sijaitsivat meso-, oligo ombrotrofisilla suotyypeillä Oriveden Lakkasuolla. Kasvillisuus kartoitettiin ja vedenpinnat mitattiin aloilta ennen käsittelyä vuonna 2000 sekä vuosina 2001–2003 ja 2009. Aineisto analysoitiin TWINSPAN- (PC-Ord), PRC ja DCA (CANOCO)-monimuuttujamenetelmillä. Tulokset osoittivat, että verrokki- ja käsittelyalat olivat samanlaisia lähtökohdiltaan, joten niitä voitiin käsittelyn jälkeen verrata toisiinsa. Kasvillisuuden rakenne vaihteli vuosien välillä myös verrokkialoilla, mikä osoittaa kasvien sopeutumiskyvyn muuttuviin sääoloihin (lämpötila, sademäärä). Vuosi 2003 erottui tutkimuksessa alhaisella vedenpinnantasolla, mutta toisaalta myös ainavihantien varpujen suuren peittävyyden osalta. Vuoteen 2009 mennessä kasvillisuuden erityisesti sarojen peittävyys väheni. Ravinteikkaimmilla toistoilla kasvillisuuden vasteet vaikuttivat olevan vahvemmat kuin vähäravinteisilla toistoilla. Kasviryhmistä kulju- ja välipintasammalilla oli vahvimmat vasteetvedenpinnan laskuun ja mätäslajeilla heikoimmat. Tulosten mukaan kasviryhmien vasteet vaihtelevat riippuen tarkasteltavasta aikajaksosta: ensimmäiset kolme vuotta käsittelyn jälkeen suo oli häiriötilassa ja vasta sen jälkeen kasvillisuus sopeutui muuttuneisiin oloihin.