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Cinnamomum balansae Lecomte (Lauraceae) is considered as an endemic to Vietnam and is assessed as endangered. This species an ecologically and economically important tree species. To conserve the species in tropical forests, genetic diversity was investigated on the basis of ten microsatellites (single sequence repeat, SSR). In all, fifty-two C. balansae individuals of four populations in Phu Tho (Doan Hung, Thanh Son, Ha Hoa and Viet Tri city) were analyzed in thisstudy. A total of 27 alelles were observed across the studied loci. The polymorphic information content (PIC) averaged 0.43 and indicated a high polymorphic value. Other values including discrimination power (PD = 0.58), resolving power (Rp = 2.57) and Marker index (MI = 1.08) were revealed. Genetic diversity in population level was higher (Ne = 2.68; Ho = 0.47 and He = 0.37) and positive inbreeding value (Fis = 0.16). Bottleneck tests had not found of four populations. This study also showed the importance of conserving the genetic resources of C. balansae species in Phu Tho province.

In this paper, we consider the known opinion formation problem from the point of view of computational collective intelligence research, with consideration to some sociological research in the area...

Two novel secoabietane diterpenoids, oroxindols A (1) and B (2), along with two known flavones oroxylin A (3) and hispidulin (4) were isolated from the stem bark of Oroxylum indicum. Their structures were elucidated by extensive analysis of the 1D and 2D NMR as well as HR-ESI-QTOF mass spectra. Noteworthily, the isolation of compounds 1 and 2 represents the first case of 11β,13;12,13-diepoxy-12,13-secoabietane-type diterpene obtaining reported to date. In addition, compound 3 exhibited significant inhibitory effects on nitric oxide (NO) production in LPS-stimulated BV2 microglial cell line, with an IC50 value of 21.5 ± 1.1 μM.

Gymnomitrion sichuanicum Bakalin et Vilnet sp. nov. Description: Plants blackish brown, slightly glistening, sometimes with discolored leaf margin (but never erose) making patches paler in color (grading to greyish); forming loose to dense patches; rhizomatous base well-developed, originating as geotropic stolons from plagiotropic normally leaved branches, sometimes bearing scale-like leaves; freely rhizogenous, freely branching, giving rise to sterile and fertile branches; leafy branches varying in size, mostly erect, rarely creeping (and then producing erect intercalary branched or plagiotropic stolons), from 250–300 to 500–700 μm wide, 1000–2000 μm long; clavate, larger branches with cupped and ventricose leaves as if containing antheridia; larger branches dorsiventrally compressed, ribbon-vermicular. Rhizoids abundant in rhizomatous part, rare on plagiotropic branches and virtually absent in erect branches, colorless to brownish and grayish. Stem freely branched in rhizogenous part, virtually unbranched in erect shoots and sparsely producing ventral leafless stolons in creeping leafy branches; orbicular in cross section, 110–140 μm in diameter, outer cells larger than inner and with colorless walls that look like a hyalodermis, cells have large trigones and thickened walls, 10–18 μm long and 8–12 μm wide, inner cells with brown-rusty colored cell walls, thin-walled or at least thinner than outer, 7–16 μm in diameter. Leaves densely imbricate, concave to cupped, sometimes distinctly ventricose (then similar to male bracts, but no antheridia found); transversely inserted, transversely oriented, shortly decurrent on both sides, with plane to slightly to evidently recurved margin, mostly evident in lower half of the leaf, varying in shape: from transversely ellipsoidal and narrowly trapezoidal (smaller) to suborbicular and ovate (larger), leaves commonly lacerate or plicate when flattened on a slide, mostly 350–560 × 330–530 μm with larger leaves to 600 × 550 μm, divided by semicrescentic (rarely widely V-shaped) sinus descending to 1/15–1/9 of leaf length into two acute to obtuse (never rounded) lobes. Cell size strongly varying across leaf: near base, oblong 20–30 × 10–15 μm, thin-walled, with moderately sized concave trigones and occasionally occurring intermediate thickenings; in midleaf 10–15 × 7–12 μm, with slightly thickened to thin walls with large concave to convex trigones; in lobe apices subisodiametric, ca. 7–10 μm in diameter, thin-walled, with concave trigones; in leaf margin near leaf base oblong, 10–15 × 7–11 μm, thick-walled, with concave trigones; cuticle smooth throughout; trigones and cell walls always colorless, while content of the cell varies in color from colorless and greenish to brown (this determines coloration of whole plant); oil bodies in midleaf cells smooth-surfaced, homogenous, 2–3 per cell, relatively small, 2–3 μm in diameter to oblong 3–4 × 2–3 μm. Dioicous? (androecia not seen). Female plants with sequential unfertilized terminal gynoecia with 1–3 subfloral innovations; female bracts similar to larger leaves. Other generative features unknown (Figs 2, 3). Holotype:— CHINA. Sichuan Province: Kangding airport area, SW-facing gentle slope of the range, covered with communities like hummocky tundra with low Rhododendron and Pentaphylloides.Crusts in open and dry frosty weathering spot, 4474 m a.s.l., 30°07’1.2”N 101°46’40.8”E, 14 October 2017, V.A. Bakalin & K.G. Klimova China-45-2-17 (VBGI) (with tiny admixture of Isopaches decolorans. ITS1-2: MW829523, trn L-F: MW841070. Paratypes:— CHINA. Sichuan Province: Kangding airport area, SW-facing gentle slope of the range, covered with communities like hummocky tundra with low Rhododendron sp. and Pentaphylloides sp. Crusts on open and dry frosty weathering spot, 4474 m a.s.l., 30°07’1.2”N 101°46’40.8”E, 14 October 2017, V.A. Bakalin & K.G. Klimova China-45- 1-17 (VBGI) (Anthelia juratzkana dominates in the specimen); the same 4335 m a.s.l., 30°06’39.6”N 101°46’22.8”E, 14 October 2017, V.A. Bakalin & K.G. Klimova China-43-1-17 (VBGI). Differentiation: When collected, the specimens were preliminarily named as Marsupella sprucei. Indeed, the short, clavate, loosely dorsiventrally compressed shoots with imbricate leaves arising from rhizomatous base resemble M. sprucei, although different in as fundamental a feature as total absence of perianth. The leaf shape is somewhat similar to Marsupella apiculata Schiffner (1903: 249–252) (but no discolored thin-walled cells along leaf margin are present) or even M. condensata (Ångström ex Hartman (1871: 128)) Lindberg ex Kaalaas (1893: 420). The absence of a perianth suggested that it should be placed in Gymnomitrion, as was later confirmed by molecular analysis. Gymnomitrion sichuanicum provides evidence of similarity with Marsupella sprucei not only in morphology, but also in ecology: the species is growing on fine-grained soil of frosty weathering spots in heathlands with very scattered vegetation. It forms patches incrusted with mineral soil. The original specimens are quite large and collected in two sites ruling out the possibility of the taxon being an incidentally occurring dwarf modification of that species (avoiding the suggestion that well developed plants could be similar to the bulk of taxa previously referred to the genus Apomarsupella Schuster (1996: 79) found nested within Gymnomitrion, cf. Shaw et al. 2015). The genetic relatives of the species include Gymnomitrion revolutum (Nees 1836: 419–420) Philibert (1890: 34) and G. parvitextum (Stephani 1901: 165) Mamontov, Konstantinova & Potemkin (2018 [2017]: 88); those species never produce short clavate shoots in patches incrusted with soil and have a deeper, leaf sinus, never semi-crescentic and therefore could hardly be mistaken for the two aforementioned taxa. Moreover, both are epilithic taxa, not epigeal. Meanwhile, it is worth mentioning that the leaf cell network is quite similar to G. revolutum in the thin cell walls and commonly concave trigones. Genetically the most closely related species is Gymnomitrion africanum described from African Mt. Kilimanjaro (1901, leg. Uhlig, G-00046686/10873, lectotype selected by Váňa 1985). The latter species (based on the lectotype) is different from G. sichuanicum in its gibbous sinus descending to 1/4–1/3(–2/5) of the leaf length and rounded leaf lobes (versus sinus descending to 1/15–1/9 of leaf length and lobes acute to obtuse), and also in stem cross section, with outer cells with very thick walls and somewhat smaller than inner cells (versus distinctly larger, hyalodermis-like cells, but with thick walls in G. sichuanicum). Ecology and expected distribution: Despite the species being collected only three times from two neighboring sites, it is possible to describe its ecology in some detail, also taking into comparative consideration the data on the ecology of Marsupella sprucei. Gymnomitrion sichuanicum grows in highland heathlands above 4000 m a.s.l., with sparse vegetation, where Rhododendron Linnaeus (1753: 392) and Pentaphylloides Duhamel (1755: 99) patches form the shrubby clumps. Sedge patches associated with Scapania sichuanica Bakalin & Vilnet (2019: 139) and Poeltia campylata Grolle (1966a: 280) and hygrophilous mosses are typical inhabitants of wet places near streams. The remaining dominant area, however, is almost free of vegetation and comprises gravelly barrens with spots of fine-grained soil of cryogenic origin (frosty weathering spots) with scattered cushions of xerophilous or xero-tolerant species. Gymnomitrion sichuanicum occurs mostly in pure patches, although at the margin in one patch (holotype) a scanty admixture of gemmiparous plants of Isopaches decolorans (Limpricht 1880: 316) Buch (1932: 288) was observed. The other specimen (China-45-1-17) comprises Gymnomitrion sichuanicum in an admixture with Anthelia juratzkana (Limpricht in Cohn (1877: 289)) Trevisan (1877: 416). The latter associate, along with the theoretically expected water circulation in frosty weathering spots, suggest temporary moistening of the patches, probably in the spring snow-melting season, while at the time of collection (middle October) the crusts were completely dry. The gentle slope described above is intermingled with extensive rocky outcrops which support some other bryophytes including xerophilous liverworts. The same area is the type locality for Plagiochila xerophila Bakalin & Vilnet (2020: 127) described previously from dry cliffs, where grew nearby the peculiar Sino-Himalayan Gymnomitrion sinense (Bakalin & Vilnet 2020). Plagiochila xerophila is probably one of the most xerophilous representatives of Plagiochila (Dumortier 1831: 42) Dumortier (1835: 14) in Asia, which may help to illustrate the environments surrounding the type locality of Gymnomitrion sichuanicum. The climate characteristics and natural environments were discussed previously (Bakalin & Vilnet 2020), but here adding only key characteristics, based on information from Table 1: 1. The area is 500 m above the timberline (the nearest forests are slightly more than 10 km to the southeast from the collecting localities), 2) annual mean temperature is slightly negative (–2.7), with the coldest month mean temperature –17°C. The total amount of precipitation is 775 mm per year, with 55% falling in the wettest summer quarter, for the driest winter quarter the precipitation is only 16 mm per quarter. Therefore, the climate has pronounced highland monsoon characteristics with a cold, dry winter. These characteristics may be similar to the climate in the area of distribution of Marsupella sprucei. Although the latter is largely distributed in areas with oceanic/suboceanic climates, the character of the growing season is somewhat similar (wet), whereas the winter is much dryer in Sichuan (versus, e.g., in suboceanic NE Asia), and negative temperatures are associated with the absence of snow cover that seems to be suitable for many Gymnomitrion, but not so for Marsupella Dumortier (1822: 114). The collecting area is on the southeast edge of the Tibetan Province of the Irano-Turanian floristic region (cf. Chang 1981, Takhtajan 1986) and the collected species likely belongs to the Tibetan element and may be much more widely distributed along the Tibetan highlands and probably northern slope of the Himalaya. The same was previously suggested for Plagiochila xerophila (Bakalin & Vilnet 2020)., Published as part of Bakalin, Vadim, Vilnet, Anna, Long, David, Klimova, Ksenia, Maltseva, Yulia, Nguyen, Van Sinh & Ma, Wen Zhang, 2022, On two species of Gymnomitrion (Gymnomitriaceae, Marchantiophyta) in the Eastern Sino-Himalaya, pp. 117-136 in Phytotaxa 533 (2) on pages 123-125, DOI: 10.11646/phytotaxa.533.2.1, http://zenodo.org/record/6036331, {"references":["Schiffner, V. (1903) Studien uber kritische Arten der Gattungen Gymnomitrium und Marsupella (Fortsetzung). Osterreichische Botanische Zeitschrift 53 (6): 246 - 252. https: // doi. org / 10.1007 / BF 01679557","Hartman, C. J. (1871) Handbok i Skandinaviens flora, tionde upplagan, sednare delen: mossor. Zacharias Haeggstroms forlag, Stockholm, 179 pp.","Kaalaas, B. (1893) Levermosernes udbredelse i Norge. Nyt Magazin for Naturvidenskaberne 33 (4 / 5): 289 - 490.","Schuster, R. M. (1996) Studies on antipodal hepaticae. XII. Gymnomitriaceae. Journal of the Hattori Botanical Laboratory 80: 1 - 147.","Shaw, B., Crandall-Stotler, B., Vana, J., Stotler, R. E., von Konrat, M., Engel, J. J., Davis, E. C., Long, D. G., Sova, P. & Shaw, A. J. (2015) Phylogenetic relationships and morphological evolution in a major clade of leafy liverworts (phylum Marchantiophyta, order Jungermanniales): suborder Jungermanniineae. Systematic Botany 40: 27 - 45. https: // doi. org / 10.1600 / 036364415 X 686314","Nees, C. G. (1836) Naturgeschichte der Europaischen Lebermoose, vol. 2. August Rucker, Berlin, 499 pp.","Philibert, H. (1890) Sur la fructification du Marsupella revoluta Dumortier. Revue Bryologique 17 (3): 33 - 34.","Stephani, F. (1901) Species Hepaticarum 2. Bulletin de l'Herbier Boissier (ser. 2) 1 (2): 140 - 177.","Mamontov, Yu. S., Konstantinova, N. A., Vilnet, A. A., Potemkin, A. D., Sofronova, E. V. Gamova, N. S. (2018) On resurrection of Marsupella parvitexta Steph. (Gymnomitriaceae, Marchantiophyta) as a semi cryptic species of the genus Gymnomitrion. Nova Hedwigia 106 (1 - 2): 81 - 101. https: // doi. org / 10.1127 / nova _ hedwigia / 2017 / 0466","Vana, J. (1985) Notes on Some African Hepatic Genera 6 - 9. Folia Geobotanica et Phytotaxonomica 20: 81 - 99.","Linnaeus, C. (1753) Species plantarum, ed. 1 - 2. Impensis Laurentii Salvii, Holmiae [Stockholm], 1200 pp. https: // doi. org / 10.5962 / bhl. title. 669","Duhamel du Monceau, H. L. (1755) Traite des Arbres et Arbustes qui se cultivent en France en pleine terre, T. 2. Guerin & Delatour, Paris, 479 pp.","Bakalin, V., Vilnet, A., Ma, W. Z. & Klimova, K. (2019) The differentiation and speciation of Scapania javanica and S. undulata complexes in the Eastern Sino-Himalayas and perimeters for Scapania sect. Stephania (Scapaniaceae, Hepaticae). Phytotaxa 400 (3): 123 - 144. https: // doi. org / 10.11646 / phytotaxa. 400.3.2","Grolle, R. (1966 a) Die Lebermoose Nepals. Khumbu Himal, Ergebnisse des Forschungsunternehmens Nepal Himalaya 1 (4): 262 - 298.","Limpricht, K. G. (1880) Neue und Kritische Lebermoose. Jahresbericht der Schlesischen Gesellschaft fur Vaterlandische Cultur 57: 312 - 316.","Buch, H. (1932) Vorarbeiten zu einer Lebermoosflora Fenno-scandias. I. Ein Versuch zur Aufspaltung der Gattungen Lophozia Dum. und Sphenolobus Steph. Memoranda Societatis pro Fauna et Flora Fennica 8: 282 - 297.","Trevisan, V. B. A. (1877) Schema di una nuova classificazione delle Epatiche. Memorie del Reale Istituto Lombardo de Scienze e Lettere (Serie 3), Classe di Scienze Matematiche e Naturali 4 (13): 383 - 451.","Dumortier, B. C. J. (1831) Sylloge Jungermannidearum Europae indigenarum. J. Casterman, Tournay, 100 pp. https: // doi. org / 10.5962 / bhl. title. 22343","Dumortier, B. C. J. (1835) Recueil d'Observations sur les Jungermanniacees. J. - A. Blanquart, Tournay, 27 pp. https: // doi. org / 10.5962 / bhl. title. 731","Dumortier, B. C. J. (1822) Commentationes botanicae. Ch. Casterman-Dien, Tournay, 118 pp. https: // doi. org / 10.5962 / bhl. title. 10534","Chang, D. H. S. (1981) The vegetation zonation of the Tibetan Plateau. Mountain Research and Development 1 (1): 29 - 48.","Takhtajan, A. (1986) Floristic regions of the world (translated by T. J. Crovello & A. Cronquist). Berkeley, University of California Press, 544 pp."]}

Two new phenolic glycosides, oroxylumosides A (1) and B (2), along with four known compounds darendoside A (3), leucosceptoside A (4), acteoside (5) and decaffeoylacteoside (6) were isolated from the stem bark of Oroxylum indicum. Their structures were elucidated by extensive analysis of the 1 D and 2 D NMR as well as HR-ESI-QTOF-MS. In addition, compounds 1 − 4 exhibited inhibitory effects on NO production in LPS-stimulated BV2 microglial cell line with IC50 values of 58.2 ± 2.9, 70.6 ± 3.5, 56.8 ± 2.8 and 61.1 ± 3.1 µM, respectively.

Mung bean residues stimulate the hatching of soybean cyst nematode (SCN). In our previous study, combined incorporation of mung bean residues and biochar into soil can be effective in suppression of the soybean cyst nematode (SCN), Heterodera glycines, in the upper layer soil. However, there are no data available as to whether such effects are transmissible, and could for example be manifest in subsoil zones where such incorporation is confined to topsoils, via water-based pathways. We evaluated the effects of leachate passage from a biochar-amended soil in an upper soil zone to a lower zone in a microcosm-based system, upon a range of physicochemical properties and density of SCN. Disturbed soil was filled in a total of 9 cylindrical cores with two layers. The upper layer (0–15 cm) was amended with biochar at rates equivalent to 0, 0.3% or 1.8%, with bulk density set at of 1.1 g cm−3. The lower layer (15–25 cm) without biochar amendment was compacted to 1.2 g cm−3. Mung beans were grown for two weeks and incorporated into the upper layer. Water was surface-applied to the cores 4, 6, and 8 weeks after mung bean incorporation. After 16 weeks, the upper and lower layer soils were separately collected and assayed. The presence of biochar in the upper layer reduced the abundance of free-living nematodes, mainly bacterivorous, but increased that of a predator genus Ecumenicus in this zone. In the lower layer of soil under a biochar-amended upper layer, available P and soluble cations were increased as were abundances of total nematodes including Ecumenicus, resulting in greater maturity index, basal and structure indices. Notably, SCN density was decreased in lower zones by more than 90% compared to zero-biochar controls. This demonstrates that the effects of biochar upon soil properties, including impacts on biota and plant pathogens, are transmissible.

Ha Long bay - Cat Ba island located in the Northeast of Vietnam, in the area of Ha Long city (Quang Ninh province) and Cat Hai island district (Hai Phong city) is the largest limestone island in Vietnam. Features of biodiversity include the seven typical ecosystems of tropical limestone islands, namely tropical rainforest ecosystem, cave ecosystem, mangrove ecosystem, tidal ecosystem, coral reef ecosystem, soft-bottom ecosystem. Ha Long - Cat Ba also represents a high level of species diversity with 4,622 species of plants and animals on land and in the sea. In particular, on land there are 2,464 species, accounting for 53.3% and under the sea there are 2158 species, accounting for 46.7%. Up to 16 species and 114 species have been recorded in the Vietnam Red List and in the IUCN List, respectively. Together with hundreds of rare and precious species at national and regional levels, there are species of global conservation value, demonstrating that Ha Long bay - Cat Ba archipelago can possibly be a world heritage site according to the criteria of biodiversity (ix and x criteria).

In a rice-shrimp cropping system in Vietnamese Mekong Delta, more effective techniques are required to remediate the saline soils for lowing salinity to secure rice growth and productivity. The objective of this study was to evaluate the reclamation potential of biochar and calcium in laboratory experiments using a saline soil sample from the rice-shrimp system. Our hypothesis was that the addition of biochar might improve the infiltration rate, so remove salts more effectively, in particular sodium, from the saline soil. The experiment was set up with two kinds of rice husk biochar at rates of 0 and 50 g kg-1 combining with three levels of CaO (0, 0.5 and 2 g kg-1 soil, equivalent to 0, 0.5 and 2 Mg ha-1, respectively). Results indicated that biochar enhanced significantly drainage speed by 4 times compared to the control without biochar application. After leaching, exchangeable sodium percentage (ESP) in the soils was significantly lower in biochar treatments than in the control. Some other chemical indicators (K:Na and Ca:Na ratios) were also higher in biochar treatments. Although both biochars effectively removed salts from the saline soil, biochar with a lower Na+ adsorption capacity, a lower surface area and a higher amount of salts performed better in removing Na+ from soil. Combined application of biochar and CaO at low dose was more effective in improving soil properties related to Na+ leaching and ESP.

Cat Ba islands, located in the North East of Vietnam, in the area of Ha Long City (Quang Ninh Province) and Cat Hai Island District (Hai Phong City), is the largest limestone archipelago in Vietnam. Typical limestone islands including tropical rainforests, caves, mangroves, tidal ecosystems, coral reefs, and soft-bottom ecosystems characterized the area. Cat Ba hosts high level of diversity with 4622 recorded species of marine and terrestrial plants and animals. Among animals, 130 species, mainly corals, are threated and are listed in the Vietnam Red Book and in the IUCN Red list; the marine mammal Sousa chinensis and the sea turtle Eretmochelys imbricata are considered in danger and in an extremely critical state. Saltwater lakes are known to host several endemic and rare species. In Cat Ba these peculiar habitats are numerous and their biotic community includes 165 marine vegetal and animal species; some of them are endemic or rare like several sponge species and the jellyfish Mastigias sp. Rare and precious species of global conservation value, the unique naturalistic characteristics of the area, hosting various and rich ecosystems, support Ha Long Bay, Cat Ba Archipelago as a world heritage site according to the criteria of biodiversity (IX and X criteria).

Two new phenolic glycosides, oroxylumosides A (

Knowledge diffusion and opinion formation are important research topics in the area of communication in social networks. We present our generic model with interchangeable variants for processing messages from other members of the group. We describe several generic aspects of communication, like learning, persuasion, or polarization, and apply them in our model. We then show how this simple change leads to different results for the communication process of the whole group. We show how the model with interchangeable integration strategies is applicable for modeling various aspects of online social network and real life communication.

Rice ecosystems vary greatly in climate, edaphic conditions, landscape heterogeneity, agricultural management and biodiversity. However, ongoing land use intensification and conversion to large-scale monoculture are threatening this diversity. We analyzed how rice-growing regions in Southeast Asia differ in diversity and composition of vascular plants in paddy rice ecosystems, and how the local and regional biodiversity of these plants is determined by variations in abiotic conditions, habitat type (paddy vs. bunds) and the proximity of non-paddy habitats. The vegetation of paddies and their bunds was surveyed in seven important rice production regions located in highlands and lowlands of Vietnam and the Philippines. Within the regions we sampled 67 pairs of study sites comprising a total of 122 paddies and 134 bunds. We identified major drivers of field-level weed diversity (alpha diversity) separately for bunds and paddies. Species turnovers (beta diversity) across sampling sites, between paddies and their bunds, and between regions were visualized using the Bray-Curtis coefficient of dissimilarity and DCA ordinations. Species richness on bunds was mainly influenced by the proximity of non-paddy habitats, mean annual temperature and soil acidity. Soil moisture was the decisive factor for the variation in paddy weed richness. In both habitat types, Shannon diversity and the number of insect-pollinated plants showed patterns similar to species richness. Regional differences in plot species richness were stronger on bunds than in paddies. Species turnover was high among habitat types and between upland and lowland regions. Future ecological engineering approaches can build on our findings to promote pollination services more efficiently in Southeast Asian rice landscapes.

LEGATO stands for “Land-use intensity and Ecological EnGineering—Assessment Tools for risks and Opportunities in irrigated rice based production systems.”

Rice is among the most important crops for human nutrition. The need to increase yields is commonly achieved by agricultural intensification that often comes along with negative impacts on the environment. In 2011, the interdisciplinary LEGATO project was launched with the aim to advance sustainable rice production. A key feature for sustainable rice production is silicon (Si) availability. Si can e.g. improve rice crop resistance against pathogens and prevent the uptake of toxic metals. Herein, we introduce the characteristics of the seven LEGATO study regions in Vietnam and the Philippines (i.e., climate, geology, soils, agricultural practices) ranging from lowlands with intensive production to mountain regions with extensive and traditional production systems. Secondly, we show data on concentrations of plant-available Si (Si pa ) in topsoils of paddy fields (Ap + Arp horizons) and of sites with an alternative land-use (forest, upland crops), and discuss factors determining spatial differences in Si pa concentrations. Results show that Si pa concentrations in topsoils of paddies (assessed by acetate extraction) greatly differ between Philippine (141–322 mg Si kg −1 ) and Vietnamese (20–51 mg Si kg −1 ) regions. This can be explained by differences in geo-/pedologic conditions between the countries. Large Si pa concentrations in the Philippines are due to recent rock formation by active volcanism, hence, by a large Si pa input due to mineral weathering in recent geologic history. Land-use can also affect Si pa in topsoils: in Philippine regions, Si pa concentrations were significantly larger for paddies than for other land-use types. In some of the Vietnamese paddies, Si pa concentrations are below critical values, thus might limit plant growth. Many Vietnamese farmers export Si from fields by removing straw residues with the harvest. Our subsequent research thus aims to test whether changes in harvest residue management can improve the Si supply to plants in Vietnamese regions.

Dichotomous keys are the most popular type of identification keys. Studies have been conducted to evaluate dichotomous keys in many aspects. In this paper we propose an index for quantitative evaluation of dichotomous keys (Edicho). The index is based on the evenness and allows comparing identification keys of different sizes.

The management of biodiversity represents a research topic that needs to involve not only several (sub-) disciplines from the natural sciences but, in particular, also the social sciences and humanities. Furthermore, over the last couple of years, the need for the integration of other kinds of knowledge (experience based or indigenous knowledge) is increasingly acknowledged. For instance, the incorporation of such knowledge is indispensable for place-based approaches to sustainable land management, which require that the specific ecological and social context is addressed. However, desirable as it may be, such an engagement of the holders of tacit knowledge is not easy to achieve. It demands reconciling well-established scientific procedural standards with the implicit or explicit criteria of relevance that apply in civil society a process that typically causes severe tensions and comes up against both habitual as well as institutional constraints. The difficulty of managing such tensions is amplified particularly in large integrated projects and represents a major challenge to project management. At the Helmholtz Centre for Environmental Research - UFZ, several integrated research projects have been conducted over the past years in which experience has been gained with these specific challenges. This paper presents some of the lessons learned from large integrated projects, with an emphasis on project design and management structure. At the centre of the present contribution are experiences gained in the coordination and management of LEGATO (LEGATO stands for Land-use intensity and Ecological EnGineering - Assessment Tools for risks and Opportunities in irrigated rice based production systems, see www.legato-project.net), an ongoing, large-scale, inter- and transdisciplinary research project dealing with the management of irrigated rice landscapes in Southeast Asia. In this project, local expertise on traditional production systems is absolutely crucial but needs to be integrated with natural and social science research to identify future-proof land management systems.

Filling the holes of a triangular mesh has been studied for many years in the field of geometric modeling. This research is one of the reconstructing steps of a triangular mesh (or called refinement of a mesh) in order to improve the quality of a 3D triangular surface. With the same idea of hole filling in a mesh, filling in the holes of a 3D point cloud is still a challenge to the researchers. This paper describes a method for filling holes in an elevation surface of 3D point clouds structured in a 3D grid. The novelty of the method is processed directly on the 3D point clouds consisting of two steps. In the first step, we determine the boundary of hole. In the second step, we fill the holes based on the computation of tangent plane for each boundary point. Following clock-wise direction on the hole boundary, we compute and insert missing points on each tangent plane. This process is repeated and refined ring by ring from the hole boundary to the inside of the hole. The obtained results show that the processing time of algorithm is very fast, the output surfaces preserve their initial shapes and local curvatures.

Unlike the other currently available identification software, BioKeys allows the users to create and use own polyclave identification keys of various taxonomic levels. The information of dedicated taxonomic level is stored in the head line of the key file so that BioKeys can understand and search in the right field of the database for the records of matched taxa. The results of database referencing or specimen identification will be displayed in a form of web page. Besides, utilities are available for creating and managing the database, for analyzing the polyclave identification key. An example of using BioKeys is provided with polyclave key of plant families of Magnoliophyta that has been created based on the punched-card system of Betel Hansen and Knud Rahn (1969).

PlantsVN is a software that combines the plant database functions with the utility of family identification of plant specimen. PlantsVN allows users to create and manage personal plant database and identify plant specimen. Apart from the software accompanied key, the users can easily create own keys using the key file child window. The result of the identification is documented by displaying all the taxa of the plant database matched with the characters of the plant specimen.

Seventeen taxa of meiofauna community in the Ham Luong estuary were investigated and comprised. Free-living nematodes were the most dominant and diverse group, presenting about 77% in the total of meiofauna density. Meiofauna density varied from 135.7 ± 33.5 inds/10 cm² to 1782.0 ± 199.5 inds/10 cm². The meiofauna density shows a decreasing trend from inland station to the brackish water station and it is increasing at mouth station. Significant differences in meiofauna density, diversity and Hill's indices were found between stations. The ANOSIM showed significant differences between stations in meiofauna composition (overall R = 0.972, p = 0.1%). The SIMPER analysis clarifies that the average similarity within stations was quite high, changing from EHL3 (76.2%) to EHL1 (86.1%).

The concept of “four element groups” means that all elements of a dynamic system can be divided into four groups: (1) constant elements, (2) state elements, (3) intermediate elements, (4) listed elements. This concept is realized in my MM&S-computer program with two facts. The first one is that four above mentioned element groups are correspondingly assigned four symbols: circle, square, rhombus, circle with three signs (these signs signal how we should handle this listed element at time point where its value has not been declared). These symbols are used to draw simulation scheme of interaction of the system elements. The concept of “change rate” means that every state element has a change rate as its attribute. Other elements of the system affect current state element by affecting its change rate. The current state element affects other elements of the system with its value. This concept is realized in my MM&S-computer program with the fact, that the links connect the state elements directly. In case if a state element has a incoming link, we understand that the change rate of this state element is being affected. Once change rate is an attribute of the state element, the value of the state element can be automatically used for the calculation of change rate. Realization of these above concepts make the simulation scheme of a dynamic system more clear and simple. This paper gives the reasoning for these concepts and also describes the model formats, model calculation in MM&S-computer program.

The highest numbers of nematodes with a percentage ranging from 76.4% in Cung Hau to 77% in Ham Luong estuaries. There were 92 genera (71 genera in Ham Luong and 62 genera in Cung Hau) of nematodes recorded in both estuaries. The mean nematode densities varied between 90 ± 31 - 1524 ± 269 ind.10 cm² and 105 ± 79 - 1120 ± 534 ind.10 cm² in Ham Luong and Cung Hau estuary, respectively. The nematode communities were mainly composed of Dichromadora, Daptonema, Oncholaimellus, Syringolaimus, Tripyloides, Parodontophora, Theristus and Halalaimus belonging to several dominant families, such as, Oncholaimidae, Xyalidae, Chromadoridae, Oxystominidae, Axonolaimidae and Sphaerolaimidae. In both estuaries, nematode density decreased from inland towards the mouth before they increased again at the mouth stations.