Phytosociological survey of weed plants in soybean culture in the Gurguéia Valley

Phytosociology is a set of ecological assessment methods that aim to provide a view of plant species distributions within a plant assemblage. The objective of the current study was to identify and quantify the plants designated as weeds in a glyphosate-resistant soybean crop, using a phytosociological survey of a conventional planting system on the Fazenda Agrosantos (09°27’4124.4” S and 45º01’00.4” O), Vale do Gurguéia, Monte Alegre municipality Piauí state, Brazil. The site lies at a mean altitude of 652 m. Field collections were made 15 days after initial soya planting. For sampling, a 0.40 x 0.40 m quadrat was used, thrown randomly twenty times within the experimental area. Weeds were identified and quantified using the sum of the samples obtained from the quadrat samples. Plants that lay within the quadrat were identified, counted and collected for identification, which was carried out by comparison with specialist bibliographies and weed identification manuals. Evaluated variables were: frequency, density, abundance, relative frequency, relative density, relative abundance and species importance value index. In the soybean cultivation area, 60% of the sampled species were Eudicotyledons, and a total of 8 botanical families and 10 weed species were identified. The species Cenchrus echinatus, Ipomoea asarifolia (Desr.) Roem. & Schult, Amaranthus retroflexus L. and Zea mays L showed the highest values for the analyzed variables, and should therefore be of special attention to soybean producers in the region of Vale da Gurguéia, Piauí, Brazil.

Impacts of urbanization on mangrove forests and brachyuran crabs in Penang, Malaysia

Urban development is driving the loss and subsequent fragmentation of mangrove forests in Penang, Malaysia. However, little research has focused on the implications of urbanization onto the biodiversity within mangrove forests. This study investigates and compares both vegetation and crab assemblages between urban and rural mangrove forests. Collectively, 5853 trees were recorded including 15 species from six families: Acanthaceae, Arecaceae, Lythraceae, Malvaceae, Meliaceae, and Rhizophoraceae. Avicennia marina accounted for 88.6% of all trees in the study and held the highest species importance (IV). Although the total number of mangrove tree species varied significantly between urban (14) and rural (7) mangrove forests, the mangrove forest structure based on IV did not vary significantly. In total, 633 crabs were recorded comprising 13 different species from three superfamilies: Grapsoidea, Ocypodoidea, and Paguroidea. Crab species richness did not vary between urban and rural sites, but the biomasses of five and the densities of four crab species varied significantly. Redundancy analysis (RDA) indicated that land use, salinity, and abundance of Avicennia officinalis can best describe the distribution of crab species (r2 =32.7). This study indicates that smaller fragmented urban mangroves at the east coast of Penang have a relatively high tree and crab diversity and are worth protecting, in addition to the larger mangrove forests on the west coast. The preservation of small yet interconnected mangrove sites could be critical to the recruitment of their flora and fauna and should be considered in decision-making processes.

Ecological Gradient Analysis and Environmental Interpretation of Cyclocarya paliurus Communities

Cyclocarya paliurus (Batal.) Iljinsk. is mainly distributed in the subtropical areas of China. The leaves of this species are rich in beneficial secondary metabolites exhibiting bioactivity against human diseases, including hyperlipemia, diabetes, and hypertension. To explore the adaptability and distribution characteristics along the environmental gradient of this species, investigation of the characteristics of C. paliurus communities is necessary. In this study, we established 31 sample plots, each 20 m × 20 m, and comparatively analyzed the species composition, species importance value, and tree species diversity of different C. paliurus communities in 2 years. Canonical correspondence analyses were carried out: the first between tree-species importance value and 12 environmental factors, and the second between C. paliurus population-related indices and the 12 environmental factors. On the basis of these analyses, we identified tree species varying markedly in abundance in the studied C. paliurus communities. Several tree species showed adaptive characteristics similar to those of C. paliurus. We also observed that the C. paliurus importance value varied along elevational, longitudinal, and temperature gradients. Our findings should be valuable for prediction of C. paliurus adaptive areas and mixed forest afforestation in different distribution areas.

Study on Diversity and Protection Countermeasures of Zhongshan Park in Wuhan City

Park green space is an important part of garden green space, concentrated expression of the diversity of urban plants. In order to explore the diversity of plants in the park, a typical site in Zhongshan Park in Wuhan was selected for this survey. The species importance, richness index, diversity index and evenness index were used to analyze the characteristics of plant diversity.There are a total of 184 plants of 114 genera and 64 families in Wuhan Zhongshan Park. Among them, there are 86 species of plants of 40 families and 64 genera, 60 species of plants of 26 families and 38 genera, and 26 species of herbs, 11 families and 15 genera.The richness was herb layer > tree layer > shrub layer.Pielou uniformity was herb layer > tree layer > shrub layer;Shannon-wiener diversity was herb layer > tree layer > shrub layer.Simpson diversity was herb layer > tree layer > shrub layer.The diversity of herbaceous plants in the park is high, and the index of shrub layer is generally low, with few species. Plants in the park grow well, some plants are not evenly distributed.

Rapid assessment of epiphytic pteridophyte biodiversity in Mt. Apo Natural Park, North Cotabato Province, Philippines: a comparison of disturbed and undisturbed forests

Pteridophytes are potential indicators of climate change and environmental disturbances because of their sensitivity to the changes in the environment such as sunlight intensities and humidity levels. The study was conducted to document the species and compare the diversity of epiphytic pteridophytes in two sites–the undisturbed and disturbed areas of Mt. Apo Natural Park, North Cotabato Province in the Philippines. In each site, four stations were established, each with four 20 m × 20 m plots that are at least 20 m apart from each other. Between stations, at least 100 m was maintained. In this study, 102 species of epiphytic pteridophytes belonging to 33 genera and 14 families were identified. Seven species are lycophytes and 95 species are ferns. The number of species recorded represents 10 % of all species of pteridophytes in the Philippines. Polypodiaceae was the most dominant family consisting of 13 genera and 33 species. Among these, Prosaptia was the largest genus represented by nine species followed by Selliguea with five species. Based on the Species Importance Value (SIV), Lindsaea pulchella was the most abundant species in the area studied. Abundance of epiphytic pteridophytes vary between two sites but other parameters such as species richness, evenness, Shannon-Weiner and Simpson diversity indices showed no significant differences. There were three main assemblages of epiphytic pteridophytes based on species composition with 50% overall similarity. Of the 102 species identified, 11 were threatened which represent 6.08% of the total threatened pteridophytes of the Philippines. Noteworthy is the new species record of Asplenium beccarianum for the Philippines. Unique composition of epiphytic pteridophytes was evident and the results showed that Mt. Apo is an important location for the conservation of these communities. KEYWORDS: abundance, Asplenium beccarianum, conservation, phorophtye, epiphyte

Wetland Vegetation Response to Groundwater Pumping and Hydrologic Recovery

An investigation of wetland vegetation response to groundwater alteration was conducted at the J.B. Starkey Wilderness Park, a large municipal wellfield in the area of west Florida, USA. Decades of historic groundwater withdrawal had created a gradient of impacted wetlands on the wellfield, after which time the groundwater pumping rates were reduced. Nineteen cypress dome wetlands were grouped, based on their hydrologic histories, as either most-altered (least inundation), marginally-altered (intermediate inundation), or least-altered (near-normal inundation). Annual species–level monitoring data were used to evaluate understory plant community response to the hydrologic recovery that resulted from reduced groundwater pumping. Species richness, cover, prevalence index (PI), and species importance percentages were assessed during pre- (2005–2007) and post- (2012–2014) hydrologic recovery periods. The vegetation in marginally- and most-altered wetlands responded to hydrologic recovery with increased species richness and lower PI values (i.e., greater hydrophytic character). However, species importance percentages indicated greater variation in the recovery of most-altered wetlands, where species composition often remained different from least-altered wetlands. Although reductions in groundwater pumping caused sufficient passive hydrologic recovery to elicit a vegetation response, further reductions and/or more time may be needed before the vegetation of some altered wetlands can become comparable to that of least-impacted wetlands.

Management of soil cover and its influence on phytosociology, physiology and fig production

The fig stands out as an important source of food for the human diet, especially minerals and fibers. Weeds are a major concern in the conduct of fig orchards. Therefore, the objective of this study was to evaluate the effect of management of vegetable cover of soil (CVS) on weed phytosociology, physiological characteristics and fig production. The experimental design was a randomized complete block design with four replications. The treatments consisted of six CVS managements: cover maintenance, weeding, lodging, mowing, application of herbicides diquat and glyphosate. For the constitution of the vegetal cover a consortium of three winter forage species, vetch and black oats sowed and the ryegrass remaining in the area of previous years were used. Thus, we evaluated the phytosociology of weeds present in the area, at two different times, assigning parameters related to frequency, density and abundance, which establish the species importance value index (IVI), besides the dry mass of the aerial part of the weeds. Physiological parameters and total fruit yield were evaluated at the end of the crop cycle. The different CVS management methods influenced the weed community, mainly in the diversity, density and dry mass of the aerial part. There is no interference in the physiological variables of the fig plants and in the total production of fig fruits. We highlight the maintenance of coverage and lodging as the most promising for the management of weeds found fig orchards.

Keanekaragaman Coccinellidae Predator Pada Beberapa Ekosistem Perkebunan di Kabupaten Dharmasraya

The objectives of this research were to study the species diversity and to determine the dominant species of lady bird beetle predators in high land plantation ecosystem in West Sumatera. The samples were taken by hand collection and sweep net. The data of species diversity were analyzed using Shannon-Wiener index, evenness of species were analyzed by Simpson index, and dominant species using important value index. The results showed that there were 91 individuals predator found which consisted of 7 species. The highest species diversity (1.74) and evenness (0.89) were found in Pulau Punjung. The lowest diversity and evennes (1,40) and (0,75) was found in Koto Besar. The highest species importance value index was 1,00, that was Menochillus sexmaculatus.

Species activity promote the stability of fruit-frugivore interactions across a five-year multilayer network

Although biological communities are intrinsically dynamic, with both, species and interactions changing over time, interaction networks analyses to date are still largely static. We implemented a temporal multilayer network approach to explore the changes on species roles and on the emergent structure of a seed-dispersal network over five years. Network topology was relatively constant, with four well defined interaction modules spanning across all years. Importantly, species that were present on more years, were also disproportionally important on each year, thus forming a core of temporally reliable species that are critical to the cohesiveness of the multilayer network structure. We propose a new descriptor termed species activity that reflects the number of temporal, spatial or functional layers (e.g., different years, habitats, or functions) that each species integrates, providing a simple and powerful index of species importance for multilayer network cohesion.