Black pine (Pinus nigra) barks: A critical evaluation of some sampling and analysis parameters for mercury biomonitoring purposes

Abstract Tree barks are increasingly used as biomonitors of airborne pollutants. However, many authors stress the poor comparability of the results achieved in different studies. This drawback is mainly caused by a poor understanding of the critical sampling parameters to be considered. To minimize the biases that could be introduced during sampling, in this study the barks of Pinus nigra J.F. Arnold from thirteen sites were investigated in the abandoned Mt. Amiata mercury (Hg) mining district (Southern Tuscany, Italy) and surroundings. The influence of some sampling and analyzing parameters on Hg content was critically assessed. At each site, a total of eight bark samples were taken from a single tree at two heights (70 cm and 150 cm from soil) and at four different sides of the trunk, corresponding to the four cardinal directions; a composite soil sample was also collected. Mercury contents in barks range from 0.1 to 28.8 mg/kg, and are correlated with soil Hg contents (1–480 mg/kg), indicating that barks record both gaseous Hg concentrations in air, and wind-transported Hg-bearing particulate. For each tree, samples at 70 cm and 150 cm show Hg contents of the same order of magnitude, even if values for 150 cm are slightly less dispersed, possibly because barks at 70 cm are more influenced by random soil particles. There is no statistically significant dependence of Hg content on direction and tree age. Simulated rain events cause a negligible loss of Hg from barks. Results suggest that a convenient sampling practice for Pinus nigra is to collect a bark slice (typically 1–2 mm) within the outermost 1.5 cm layer

Investigations on tree species suitable for the recultivation of degraded land areas in Central Amazonia.

In cooperation with the Embrapa Amazonia Ocidental in Manaus (Amazonas, Brasil) and three German projects (ENV 23, ENV 45, ENV 52), in the year 2000 we especially investigated (1) photosynthesis and carbohydrate allocation and (2) the plant-water relationships of the selected tree species. Special emphasis was given to the three species of the family Meliaceae. Comparative experiments have been done for monoculture, polycultures, enrichment cultures, and primary forests.bitstream/item/198164/1/Id-6216-todo.pdfAnnual Report 2000

On Approximating the Number of kk-cliques in Sublinear Time

We study the problem of approximating the number of $k$-cliques in a graph when given query access to the graph. We consider the standard query model for general graphs via (1) degree queries, (2) neighbor queries and (3) pair queries. Let $n$ denote the number of vertices in the graph, $m$ the number of edges, and $C_k$ the number of $k$-cliques. We design an algorithm that outputs a $(1+\varepsilon)$-approximation (with high probability) for $C_k$, whose expected query complexity and running time are O\left(\frac{n}{C_k^{1/k}}+\frac{m^{k/2}}{C_k}\right)\poly(\log n,1/\varepsilon,k). Hence, the complexity of the algorithm is sublinear in the size of the graph for $C_k = \omega(m^{k/2-1})$. Furthermore, we prove a lower bound showing that the query complexity of our algorithm is essentially optimal (up to the dependence on $\log n$, $1/\varepsilon$ and $k$). The previous results in this vein are by Feige (SICOMP 06) and by Goldreich and Ron (RSA 08) for edge counting ($k=2$) and by Eden et al. (FOCS 2015) for triangle counting ($k=3$). Our result matches the complexities of these results. The previous result by Eden et al. hinges on a certain amortization technique that works only for triangle counting, and does not generalize for larger cliques. We obtain a general algorithm that works for any $k\geq 3$ by designing a procedure that samples each $k$-clique incident to a given set $S$ of vertices with approximately equal probability. The primary difficulty is in finding cliques incident to purely high-degree vertices, since random sampling within neighbors has a low success probability. This is achieved by an algorithm that samples uniform random high degree vertices and a careful tradeoff between estimating cliques incident purely to high-degree vertices and those that include a low-degree vertex

Investigations on tree species suitable for the recultivation of degraded land areas in central Amazonia.

During the first phase of the project (january 1, 1995 until april 30, 1998), the influence of the water and element supply of tree different plantation systems on the growth and wood formation of eight native tree species (Swietenia macrophylla, Carapa guianensis, Cedrela odorata, Dipterex odorata, Hymenaea courbaril, Ceiba pentandra, Virola surinamensis, Tabebuia heptaphylla) was investigated. In 1998, the data were analyzed. The results subsequently served as a basis for the second phase of the project (comp. chapter 5) which should give deeper insight into the relationship between exogenous and endogenous input, the plant metabolism, and the wood formation and wood quality of plantation-grown trees. due to the results obtained in these studies in the second phase of the project, special attention is given to the subsequent species : Swietenia macrophylla, Carapa guianensis, Cedrela odorata, Dipterex odorata, and Hymenaea courbaril. Corresponding investigations are carried out in the plantation system I (monoculture system) in comparison to system III (enrichment system). Supplementary studies on the environment-tree growth relationship of Swietenia macrophylla and Carapa guianensis are carried out in a mixed culture system (system II, comp. Schmidt et al. 1999, chapter 5). For the study on wood quality and the significance of endogenous factors for wood formation experimental areas of the Instituto Nacional de Pesquisa da Amazonia ( INPA, Manaus) 45 km north of Manaus, and some trees from primary forests of the region were included in this study.bitstream/item/201400/1/Investigations-on-Tree-Species-Suitable....pdfAnnual Report 1998 Ed. by J. Bauch; O. Dünisch, L. Gasparotto; C. de Azevedo; R. de Lima; R. de Morais

Effect of mycoviruses on growth, spore germination and pathogenicity of the fungus Fusarium circinatum

Producción CientíficaAim of the study: To assess the impact on two mycoviruses recently described in F. circinatum mitovirus 1, and 2-2 (FcMV1 and FcMV2-2) on i) mycelial growth, ii) spore germination and iii) relative necrosis. Material and methods: Fourteen monosporic strains of F. circinatum (one of each pair infected with mycoviruses and the other without them) of the pathogen with and without viruses were selected for the assay. The statistical analysis, were a linear mixed model of analysis of variance considering one between-subjects factor (isolate) and one within-subjects factor with four levels (1=without viruses, 2=only virus FcMV1, 3=only virus FcMV2-2 and 4=both viruses). Main results: Colony growth rates of F. circinatum isolates were significantly reduced in presence of mycoviruses (p=0.002). The spore germination was also reduced in the F. circinatum isolates containing mycovirus as compared to mycovirus-free isolates (p<0.001). No significant differences in lesion lengths caused by F. circinatum were found in relation to the presence/absence of mycovirus (p<0.61). Research highlights: Reduction of the percentage of spore germination in the isolates of F. circinatum with mycovirus infections, as compared to free isolates, provides indications of reduction of metabolic activity and plant physiology are discussed. The lack of significant differences found in the length of the lesions caused by F. circinatum with respect to the presence/absence of mycovirus, indicates that further studies with a larger number of variables are required.Ministerio de Economía, Industria y Competitividad (projects AGL2012-39912 and AGL2015- 69370-R)European Cooperation in Science and Technology (COST Action FP1406 PINESTRENGTH)Portuguese Foundation for Science and Technology (grant SFRH/BPD/122928/2016

Annual Report of the Secretary of the Treasury on the state of the finances for the year 1885

Part 2 of 249-1Annual Report of the Sec. of the Treasury. [2384-2385] Year ending 30 June 1885; Indian expenses.1885-9

Maine Alumnus, Volume 65, Number 2, March 1984

Contents: The Donna Browne Story --- Weather or Not --- A 50th Birthday for the Trees --- Come Blow Your Horn --- A Pat on the Back for a Bear Who Dunn Goodhttps://digitalcommons.library.umaine.edu/alumni_magazines/1331/thumbnail.jp