25 research outputs found
Phosphorus Fertilization Increases Biomass and Nutrient Accumulation Under Improved Fallow Management in a Slash-and-Mulch System in Eastern Amazonia, Brazil
Intraspecific N and P stoichiometry of Phragmites australis: geographic patterns and variation among climatic regions
Geographic patterns in leaf stoichiometry reflect plant adaptations to environments. Leaf stoichiometry variations along environmental gradients have been extensively studied among terrestrial plants, but little has been known about intraspecific leaf stoichiometry, especially for wetland plants. Here we analyzed the dataset of leaf N and P of a cosmopolitan wetland species, Phragmites australis, and environmental (geographic, climate and soil) variables from literature and field investigation in natural wetlands distributed in three climatic regions (subtropical, temperate and highland) across China. We found no clear geographic patterns in leaf nutrients of P. australis across China, except for leaf N:P ratio increasing with altitude. Leaf N and N:P decreased with mean annual temperature (MAT), and leaf N and P were closely related to soil pH, C:N ratio and available P. Redundancy analysis showed that climate and soil variables explained 62.1% of total variation in leaf N, P and N:P. Furthermore, leaf N in temperate region and leaf P in subtropical region increased with soil available P, while leaf N:P in subtropical region decreased with soil pH. These patterns in P. australis different from terrestrial plants might imply that changes in climate and soil properties can exert divergent effects on wetland and terrestrial ecosystems
Nitrogen and phosphorus addition differentially affect plant ecological stoichiometry in desert grassland
Photosynthetic traits of tree species in response to leaf nutrient content in the central Amazon
Rainforest tree species are often found on poor soils where essential nutrients may be in low concentrations. Here, we determine the effect of nutrients (N, P, Ca, Mg and K) in photosynthetic traits in five rainforest tree species from central Amazonia. Gas exchange parameters were measured with an infrared gas analyzer in four saplings (1–3 m tall) per species using two leaves per plant. Data on gas exchange and leaf nutrient content (N, P, K, Ca and Mg) were collected between August and November, 2010. Specific leaf area (SLA) and leaf thickness (LT) were also determined. Potential photosynthesis per unit mass (Apot-mass), maximum carboxylation velocity of Rubisco (Vc-max) and electron transport rate (Jmax) were responsive to variation in leaf nutrient content per unit mass. On a mass basis, P content was positively correlated with N, Mg, and K content; Mg content was positively correlated with K content. However, no correlation was found between the content of P, Mg, K and Ca, or between Ca, Mg, K and N. SLA and LT were strongly related to Apot-area, Vc-max and Jmax (per unit area). Our study shows in situ evidence on the effect of leaf nutrients on Apot-mass, Vc-max and Jmax (per unit mass) of tree saplings in the central Amazon. The magnitude of changes in photosynthetic capacity of juvenile trees in the forest understory depends not only on N and P use efficiency, but also on the availability of K, Mg and Ca, in decreasing order. © 2015, Brazilian Society of Plant Physiology
Arctic foxes as ecosystem engineers: increased soil nutrients lead to increased plant productivity on fox dens
The coupling of leaf, litter, and soil nutrients in warm temperate forests in northwestern China
The mechanism for exclusion of Pinus massoniana during the succession in subtropical forest ecosystems: light competition or stoichiometric homoeostasis?
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Ammattiosaamisen näytöt yrityksen ja ammattiopiston yhteistyössä
Opinnäytetyön aiheena oli selvittää, miten ammattiosaamisen näytöt toimivat paikallisen osuuskaupan ja ammattiopiston yhteistyössä koskien ravintolan salipuolen tarjoilijoita. Ammattiosaamisen näytöt ovat olleet käytössä työssäoppijoiden arvioinnissa viisi vuotta. Tavoitteena oli saada tietoa näyttöjen hyödyistä työantajanäkökulmasta katsottuna sekä löytää mahdollisia kehittämiskohteita.
Opinnäytetyön teoreettisessa osassa selvennettiin työssäoppimisen ja ammattiosaamisen näytön käsitteitä, mikä on niiden merkitys ammattikoulutuksessa ja toisaalta niiden merkitys työelämälle. Lisäksi selvitettiin yritysten rekrytointikäytäntöjä ja sitä, mitä on työelämän ja oppilaitosten yhteistyö.
Tutkimuksen empiirisessä osassa käytettiin puolistrukturoitua teemahaastattelua. Haastateltavat olivat paikallisen osuuskaupan ravintoloiden esimiehiä, ja haastattelut tehtiin kuudelle henkilölle. Haastattelut nauhoitettiin ja litteroitiin sanasta sanaan tietokoneelle jatkoanalyysia varten.
Tutkimuksen tuloksena vahvistui se, että ammattiosaamisen näytöt ovat kaikille selkeä asia ja niistä on hyötyä sekä työnantajalle että opiskelijalle. Yhteistyö osuuskaupan ja ammattiopiton kanssa toimii hyvin, eivätkä näyttötilanteet ole aiheuttaneet suurempia ongelmia. Ainoastaan työssäoppijan osaamisen arviointi koetaan hankalana nykyisellä asteikolla.
Alan ammattiopistotasoista koulutusta tarvitaan edelleen Joensuun alueella, ja tutkimuksen mukaan sitä pitäisi jopa lisätä. Koulutetun työvoiman puute ei vielä ole maakunnassa suuri ongelma verrattuna pääkaupunkiseutuun, mutta uhkakuvia on jo nyt havaittavissa. Tähän tulisi yhteistyökumppaneiden kiinnittää huomiota, jotta jatkossa Joensuun alueella koulutetaan riittävästi työvoimaa alalle.The purpose of the thesis was to find out how the collaboration between a company and vocational college works concerning vocational skills demonstrations of restaurant waiters. In addition, the task was to examine if there is any benefit of skills demonstrations for the company, and how to develop co-operation. Partners for the study are a local hotel and restaurant company and a local vocational college.
The information was gathered from literature, journals, the Internet and by interviewing. In the theoretical part of the study the main issue was to explain what on-the-job learning is and what vocational skills demonstrations are, and what their consequence is for vocational education and for work life. Also how companies carry out their recruitment was clarified.
Data for this study were collected by interviewing six supervisors in partner restaurants. The results of the study show that vocational skills demonstrations are perceived well without any complexities. Rather the results indicate more utilities for students, for the company and for the vocational school.
The final result of this thesis was that it is important to keep on vocational education in Joensuu and even to enhance it. Now the lack of trained waiters is a fact in southern Finland. A vision is that it will be a threat also in eastern Finland in the future. To ensure professional labour for hotel and restaurant business, companies support for vocational education is essential