Margalef Richness Index Research Articles

Characteristics of soil animal community with different garden plants and various planting periods in Wenjiang District, Chengdu, China

In order to provide scientific guidance for soil quality evaluation and optimum management of flower and seedling industry, we investigated the characteristics of soil animal community with different garden plants and various planting periods in Wenjiang District, Chengdu. A total of 10258 soil animals belonging to 26 orders and 78 families were captured in four sampling times. There were significant differences in the taxonomic richness in the plots with different garden plants, generally highest in plots with Loropetalum chinense var. rubrum or Ginkgo biloba and lowest in plot with Zoysia japonica. The taxonomic richness was lower in the plots with different garden plants than the control. Taxonomic richness and abundance of soil fauna in Osmanthus fragrans plot did not change across sampling seasons. The abundance but not taxonomic richness of soil fauna in other plots had obvious seasonal variations. Different garden plants and various planting periods significantly influenced soil faunal diversity indices. Density-group index (DG) and Margalef richness index (D) in G. biloba plot, as well as Shannon diversity index (H) and D index in Z. japonica plot decreased significantly with the increases of planting period. The DG and D indices of soil animals in O. fragrans plot increased significantly with increasing planting period. The indices of soil animal diversity in L. chinense var. rubrum plot did not change regularly with planting period. The DG, D, and H indices were lowest in O. fragrans plot with different planting periods. Results of hierarchical clustering and canonical correlation analyse (CCA) indicated that garden plant species had stronger effects on the habitat than planting period. Responses of soil fauna to various habitats were different, with available P and soil pH having stronger effects on soil fauna. Our results indicated that soil animal community shifted with the changes of garden plant and planting period as well as management and cultivation methods. Excessive human interference and monoculture had negative effects on soil animal community and caused soil degradation.

The effects of degradation on alpine grassland resilience: A study based on meta-analysis data

Alpine grasslands on the Qinghai-Tibet Plateau (QTP) provide irreplaceable ecosystem services to local and global communities. However, intensive human activities have caused severe grassland degradation during recent decades. Due to the harsh environment, these degraded grasslands recover slowly or may be irrecoverable after they degenerate to a certain stage. To understand the changes in the resilience of alpine grassland on the QTP after degradation, we evaluated the resilience indexes of the plant, soil and plant-soil systems of grasslands at different degradation stages based on an integrated assessment system and data extracted from 53 published studies in this region. The results showed that,with grassland degradation, most plant indicators including plant height, aboveground biomass, belowground biomass, Cyperaceae, Gramineae, and soil indicators including silt, clay, soil organic carbon, soil total nitrogen, available nitrogen, available phosphorus, available potassium, and soil water content gradually decreased; soil variables including sand, bulk density, and soil temperature showed an increasing trend; and Margalef richness index, Shannon-Wiener index, Pielou evenness index, and forbs first increased and then decreased. The resilience indexes of the plant, soil and plant-soil systems all displayed an obvious downward trend with the increase of degradation degree, which indicates that reduction of grassland resilience is the coordinated degeneration of vegetation and soil. To restore degraded grassland, we should focus on improving both soil and vegetation status to enhance the resilience of grassland ecosystems.

Evaluation of the trophic status in three reservoirs in Algeria (north west) using physicochemical analysis and rotifers structure.

The aim of this study is to examine the trophic state of three reservoirs located in the northwest of Algeria based on the physicochemistry of water and the community of rotifers. The measurements of the physicochemical variables were carried out monthly over a 2-year period from December 2015 to November 2017. The rotifers were sampled simultaneously. Abiotic and biotic indices such as the Carlson index, QB/T, and TSIROT were determined in order to classify the three reservoirs according to their trophic state. Thus, the diversity indices of Shannon-Wiener (H'), Margalef richness index (D), Pielou evenness (J'), and the density were calculated in order to study the structure of the rotifers. The Kruskal-Wallis test confirmed the heterogeneity of the physicochemical quality (P value < 0.05) among the three reservoirs. A total of 71 species were identified during this study. The result of the various indices affirms this heterogeneity and indicates a trophic state hypereutrophic for the Hammam Boughrara reservoir, eutrophic for the Bakhadda reservoir and meso-oligotrophic for Sidi Yacoub. The use of canonical correspondence analysis (CCA) has shown that the structure of rotifers is influenced by local environmental factors. Some species such as the genus Brachionus species have shown their preference for extreme conditions. The use of biotic indices is highly recommended for the trophic state evaluation of reservoirs for a better water resources management.

The Denser Canopy of Mangrove Drives the Structure of Insect Communities.

Mangrove restoration in Trenggalek, East Java has resulted an age variation of mangrove ecosystem. Diverse species of insects predominantly found in mangroves were collected using yellow pan traps, swipe nets and by direct picking from three different sites. This research was conducted from April until August 2015. There are 9,181 individual insects associated with mangroves comprised of 42 species from 31 families and eight orders. The first site or the 15 years old mangrove (66.22% canopy cover) indicated the highest Shannon diversity index at 2.54, Evenness index of 0.32 and Margalef richness index of 4.84. The lowest diversity was recorded in the third site or the five years old mangrove (19.65% canopy cover), with the Shannon diversity index at 2.28, Evenness index at 0.26 and Margalef richness index at 4.59. The most abundant species located was the Eristena mangalis, with 1,724 individuals (relative abundance of 18.78%), followed by Monolepta sp. with 1,649 individuals (relative abundance of 17.96%). These are the phytophagous insects associated with mangrove leaves. This study concluded that the older mangrove ecosystem have a denser canopy that supports insect life.

Seasonal abundance and diversity of finfish in a tropical estuary, Karwar, southwest coast of India

The spatial and seasonal variability in finfish availability in the tropical Kali Estuary, in Karwar was studied from January 2017- May 2019 at three stations. A total of 26 species belonging to 9 orders and 20 families were recorded from the Kali Estuary and the order Perciformes with 16 species dominated the group (62%) followed by order Mugilliformes and Pleuronectiformes (8%). Maximum abundance was observed during the pre-monsoon season in all the stations. Excluding Ambassis ambassis which was abundant in all the stations, Caranx ignobilis dominated in all the stations. Truly marine and estuarine species of fishes recorded dominated than the freshwater estuarine ones like Etroplus suratensis, Scatophagus argus, Aplocheilus lineatus. Number of species recorded at each station during the study ranged from 11 to 25 and it was significantly different between stations. The Shannon- Wiener diversity index ranged from 2.0 to 4.6, the minimum in station 1 and maximum in station 3. The seasonal analysis of diversity also showed minimum value during the monsoon season in station 1 and maximum value in station 3. The minimum value (2.2) of Margalef richness index was also recorded in Station 1 during monsoon season and maximum value (4.2) in Station 2. When comparing the relative abundance using Pielou’s evenness index (J’) the values were in the range of 0.92 to 0.99 which was closer to one, indicating evenness in distribution. There was similarity in species composition according to different seasons except for monsoon season in Station 1. The same pattern was also evident in the MDS plot where seasonal aggregation was observed between the stations. In addition to the diversity studies, the surveys also threw light on the abundance and seasonality of candidate species suitable for mariculture like C. ignobilis, Lutjanus spp., Etroplus spp., etc. Judicious exploitation of the species could help brackishwater fish farmers.

Community diversity of ground-dwelling beetles in secondary oak Forest and its adjacent restored poplar Forest

In order to restore the vegetation of forests, China has implemented the project of restoring the farmland to the forest. With the advancement of this project, the artificial vegetation restoration area adjacent to the forest is expanding. In this study, a secondary oak forest, its adjacent restored poplar forest and the secondary oak forest-restored forest ecotone were selected as the study sample plots, and the ground-dwelling beetle community was investigated by pitfall trap method for exploring the diversity characteristics of the ground-dwelling beetle community in this complex ecosystem, in order to reveal the relationship between the ground-dwelling beetle and the environmental changes. In this study, 2458 ground-dwelling beetles belonging to 94 species of 24 families were collected from the secondary oak forest and its adjacent restored poplar forest from April to September 2017, of which Scarabaeidae, Carabidae and Silphidae were the dominant communities of ground-dwelling beetles in the sample plots. The order of the species number and individuals number of ground-dwelling beetles in the different types of vegetation was the secondary oak forest > ecotone > restored poplar forest in turn, with significant differences. The estimation of nonparametric species richness showed that the sampling intensity was not fully saturated, indicating that more surface beetle species could be collected. The Margalef richness index, Simpson diversity index (λ), Hill diversity index (N2), Pielou evenness index (E1), Hill evenness index (E2) and modified Hill evenness index (EHill) of surface beetles were significantly different in the different habitats, and higher diversity and evenness of the surface beetles were maintained in the restored poplar forest, indicating that the restoration and re-naturalization of forest vegetation could increase the insect species and community stability. The community similarity analysis indicated that the ground-dwelling beetle community among the secondary oak forest, the ecotone and the restored poplar forest was at the middle level of dissimilarity. The edge effect intensity analysis suggested that there was a negative edge effect in the ecotone between the secondary oak forest and the restored poplar forest.

Seed bank characteristics in a Pinus densata forest and its relationship with vegetation diversity in Southeast Tibet, China.

ObjectiveWe aimed to understand the basic characteristics of the underground seed bank of Pinus densata forest and its relationship with aboveground vegetation, to provide a theoretical basis for vegetation restoration.MethodsThe study sites were Dongjiu Bridge (DJ), Linji Bridge (LZ), and Birishen Mountain Scenic Spot (RB) in Gongbu Nature Reserve, Southeast Tibet, China. Species composition and distribution pattern of the underground seed bank in P. densata forest were analyzed. Germination data and field investigations were used to examine the similarities between aboveground vegetation and underground seed banks, and their responses to the environment.ResultsThere were 47 species belonging to 27 families in the underground seed bank of the P. densata forest. Asteraceae, Rosaceae, Labiatae, and Poaceae were dominant, accounting for 40.4% of the total number of families. Underground seed density was 2,114, 1,952, and 1,141 seeds/m2 in DJ, LZ, and BR, respectively. The percentage of different life‐forms in each sampling location was shown to be perennial herbs > shrubs > annual herbs > trees > subshrubs. The Shannon–Wiener diversity index, Margalef richness index, and Simpson's dominance index of each sample showed that species decreased with higher elevation, while the Pielou evenness index showed the opposite trend. Elevation, slope position, slope aspect, and slope were positively correlated with the Pielou evenness index and negatively correlated with the Shannon–Wiener diversity index, Margalef richness index, and Simpson's dominance index. The Sørensen index, comparing the similarity between the underground seed bank and aboveground vegetation of DJ, LZ, and BR was 0.46, 0.35, and 0.31, respectively.ConclusionThe underground seed bank of P. densata forest has high seed density and high species richness, but there was little similarity between aboveground vegetation and underground seed bank. Elevation and slope position had a great influence on the uniformity of species distribution.

Long-term variations in fish community structure under multiple stressors in a semi-closed marine ecosystem in the South China Sea

Daya Bay is an ecologically and economically crucial semi-closed bay along the southern coast of China. It is proven to be a stressed ecosystem and therefore obviously vulnerable to further extrinsic disturbance. This study used fish data from bottom-trawl surveys, conducted from 1985 to 2018, to analyze variations in the fish community structure over the past 30 years. The results showed that warm-water fish species were overwhelmingly dominant during all years, suggesting the bay's tropical to subtropical characteristic. By 2015, the number of fish species had decreased by 29.44% of that caught in 1987, moreover, values of the Shannon–Wiener diversity index and the Margalef richness index were lower in 2015 compared to 2004. There were evident shifts in the fish community composition from pelagic to demersal species, as suggested by the dominant species found in springtime, the dominant families, and percentages denoting the numbers of species in the main orders. Average fish body weight in landings declined from 13.4 g to 7.58 g, the body sizes of four typical commercial fish species decreased by varying degrees over the last 30 years. Abundance–biomass comparison curves suggested that the Daya Bay fish community was more stressed in 2015 than in 2004 during all seasons, except winter. In general, the fish community structure in Daya Bay is consequently in an unsteady state. Multiple anthropogenic disturbances, such as fishing (including overfishing and changes in the main fishing gears), the destruction of natural habitats, pollutants, and anthropogenically induced temperature changes, are likely to have caused obvious shifts in the bay's fish community structure. Therefore, we emphasize the need for integrating management of multiple anthropogenic stressors to achieve ecosystem-based management.

Pelagic Fish Eggs Diversity in the Nearshore Waters of Gulf of Mannar, South East Coast of India

Background: A study of the diversity, distribution and development of fish eggs and larvae as an integral part of a fishery research programme serves as a valuable aid in the proper management of fisheries. The study is also an essential prerequisite in understanding the spawning biomass of forecasting and trends of production. Information available on diversity of fish eggs from Indian waters is inadequate. The present study was conducted to understand the diversity and distribution of pelagic fish eggs in the nearshore waters of Gulf of Mannar. Methods: The present study conducted at three stations-Mandapam, Thoothukudi and Punnakayal in the waters of Gulf of Mannar, during 2017-2019. A total of 684 ichthyoplankton samples were collected. In the laboratory, the samples were sorted and identified. The diversity was calculated by Shannon-Weiner, Margalef richness index and Pielou’s evenness indices. All the diversity indices were done by using the PRIMER-E software. Result: Our investigation was taken up with objective to assess the status of pelagic fish eggs diversity in the nearshore waters of Gulf of Mannar and found to be more productive. From the diversity study, it is evident that the Punnakayal waters are habitat for a rich diversity of fish species and also a spawning and nursery ground for fishes. Fish eggs diversity is significant for management of fishery resources.

Ecology and Diversity of Zooplankton of the River Ganga at Bihar, India in Relation to Water Quality

A study was carried out to evaluate the ecology and diversity of the zooplankton of the Ganga River at Arrah from Bihar, India from January 2018 to December 2019. Varied physical and chemical parameters supporting the zooplankton and corresponding biodiversity indices were studied. The water temperature showed inverse correlation with pH, dissolved oxygen, whereas direct relationship with total alkalinity, hardness, chloride, nitrate and sulfate. A total of 23 genera of zooplankton belonging to 6 genera of Rotifera, 5 of Protozoa, 5 of Cladocera, 4 of Copepoda and 3 of Ostracoda were identified with a density from 2 to 213 ind./L. The analysis showed that density of zooplankton declined in post-monsoon and remained maximum in summer because of the various environmental and inflow characteristics of the water body. The density of zooplankton showed direct correlation with total alkalinity, hardness and chloride of water but inverse correlation with water temperature, pH and dissolved oxygen. Shannon-Weiner index, Margalef richness index, Pielou’s evenness index, Menhninick’s index and Simpson index were won’t to assess relation of water quality with zooplankton and limnological profile of the river. The diversity indices indicated moderate to high diversity of zooplankton and moderately polluted conditions of the river.

The Diversity and Utilization of Weeds in Sengon (Falcataria moluccana (Miq.) Barneby &amp; J.W.) Grimes) Agroforestry and Monoculture Pattern

Sengon (Falcataria moluccana) is a superior commodity of private forests in Java island. However, its management faces a gall rust attack. In addition, another challenge is the presence of weed disturbance which can reduce plant growth productivity. This study aims to measure the diversity and utilization of weed species in the agroforestry and sengon monoculture demonstration plots. The research method used was the method of vegetation analysis of understorey and interviews. Data analysis was performed descriptively using the importance species index, species diversity index and species similarity index.The results showed that both cropping patterns produced the same level of diversity and species richness despite differences in species density and presence. A total of 29 species of weeds were found in the agroforestry pattern and 27 types in the monoculture pattern.. Weed species diversity in agroforestry and monoculture patterns is classified as moderate with Shannon-Wienner species diversity index (H ') values of 2.47 and 2.66 respectively. Likewise, the level of species richness both pattern is classified as moderate with Margalef Richness Index (R’) value of 3.89 in monoculture and 4.23 in agroforestry. The level of species similarity between the two cropping pattern according to the Bray-Curtis Index is 0.66. The density of weeds in the monoculture pattern is higher (66.00 individuals / m2) than the agroforestry pattern (62.25 individuals / m2). Most of the weeds (67.65%) are used by people around the forest as animal feed (18 species), foodstuffs (4 species) and traditional medicine (4 species). The many species of weeds that can be utilized by the community shows that sengon forests can support food security, so that the weed control techniques recommended are manual techniques with simple tools and spatial management with F. moluccana plants.

Comparison of species diversity of butterflies between burnt and unburnt land at various levels of post-burnt land age in Mount Ciremai National Park

Forest fires occur almost every year in some locations in Indonesia, including in Mount Ciremai National Park (TNGC). Different age of land due to fire is believed to affect its biodiversity including the losses and gains of butterfly species. The study aims to estimate the diversity and composition of butterfly species and estimate the loss and gain of butterflies due to fire at different levels of post-burnt land age. The study was conducted on April 1st to May 21st, 2019 at three locations of burnt land with different ages (1, 2, and 4 years post-burnt). The Pollard Transect Method was used to estimate and analyze the species number of butterflies, the Margalef richness index, species diversity index, and species evenness index. The referential habitat as the basic approach was used to determine the losses and gains of butterfly species in each land. The results showed that there were 76 species of butterflies in all land, the highest index of Margalef was found on 2-year-old of burnt land, the highest index of diversity on 1-year-old of burnt land, and index of Evenness close to 1. The highest gains of diversity due to fire was found on 4-year-old of burnt land at 84.21% while the highest losses of diversity due to fire on 2-year-old of burnt land at 45.71%. In conclusion, there are differences in species diversity, losses, and gains of butterflies at various levels of post-burnt land age in Mount Ciremai National Park.

Comparative phytosociological assessment of three terrestrial ecosystems of Wayanad Wildlife Sanctuary, Kerala, India

Phytosociological studies were conducted in three vegetation types in the WS II area of Wayanad Wildlife Sanctuary. In each vegetation type, 85 quadrats (10 x 10 m) were laid to quantify the vegetation. Natural forest showed comparatively higher species richness than plantation and vayal (swamps/low lying grassland). In natural forest 96 plant species were present while it was 70 and 66 respectively in plantation and vayal. Fabaceae was the dominant family in all the three vegetation types. The natural forest was dominated by Chromolaena odorata, followed by Lantana camara, Mimosa pudica, Terminalia elliptica, Glycosmis pentaphylla. In the plantations, Chromolaena odorata, Tectona grandis, Mimosa pudica and Glycosmis pentaphylla showed dominance. The vayal was dominated by Arundinella leptochloa. The second most dominant species in the vayal was Chromolaena odorata. Other dominant species were Kyllinga nemoralis and Sporobolus tenuissimus. Among the three, vayal recorded the highest Simpson Diversity Index. The highest Berger-Parker Dominance Index value in plantation indicates the presence of dominant species. Natural forests recorded highest Margalef Richness Index and the least was in vayal. The highest Pielou’s Wiener Equitability Index in vayal indicated all species are evenly distributed.&#x0D;

Floristic Variation of Tree Communities and Their Association with Soil Properties in Pulau Jerejak, Penang, Peninsular Malaysia

This study was conducted at Pulau Jerejak, Penang to determine the floristic variation of its tree communities. A 0.5-hectare study plot was established and divided into 11 subplots. A total of 587 trees with diameter at breast height (DBH) of 5 cm and above were measured, identified and recorded. The tree communities comprised of 84 species, 63 genera and 32 families. The Myrtaceae was the most speciose family with 10 recorded species while Syzgium glaucum (Myrtaceae) was the most frequent species. The Myrtaceae recorded the highest density of 306 individuals while Syzgium glaucum (Myrtaceae) had the highest species density of 182 individuals. Total tree basal area (BA) was 21.47 m2/ha and family with the highest BA was Myrtaceae with 5.81 m2/ha while at species level, Syzgium glaucum (Myrtaceae) was the species with the highest total BA in the plot with value of 4.95 m2/ha. The Shannon˗Weiner Diversity Index of tree communities showed a value of 3.60 (H'max = 4.43) and Evenness Index of 0.81 which indicates high uniformity of tree species. The Margalef Richness Index (R') revealed that the tree species richness was 13.02. Myrtaceae had the highest Importance Value of 20.4%. The Canonical Correspondence Analysis (CCA) showed that Diospyros buxifolia (Ebenaceae) and Pouteria malaccensis (Sapotaceae) were strongly correlated to low pH. Dysoxylum cauliflorum (Meliaceae) and Eriobotrya bengalensis (Rosaceae) were correlated to phosphorus (P) and calcium ion (Ca2+), respectively. Therefore, the trees species composition at Pulau Jerejak showed that the biodiversity is high and conservation action should be implemented to protect endangered tree species. Keywords: Floristic variation; Tree communities; Trees composition; Pulau Jerejak; Species diversity

Different Habitat Types Affect Bird Richness and Evenness

More studies are needed on the mechanism and effective prediction of bird diversity in various habitats. The primary purpose of this study was to explore the difference in the species richness and evenness of various habitats. The secondary purpose was to explore which habitat types and compositions predict a high bird diversity. The 2010–2016 Taiwan Breeding Bird Survey was used to analyze the relationship between landscape habitat and bird ecology. Landscape habitat type was divided into seven categories and 26 sub-types: forestland, farmland, grassland, freshwater wetland, aquaculture pond and saltpan, coastland, and building area. Four ecological indexes were used: the number of bird individuals, the number of species, the Margalef Richness Index, and the Pielou Evenness Index. The result indicated that forestland decreased bird numbers, except in a windbreak forest. Natural and farmland-related habitats increased bird species richness. Similarly, the natural habitat increased species evenness. Urban greenspace could not replace the effect of forestland on species richness and evenness. Conifer forest, bamboo forest, windbreak forest, mixed tree, tall grassland, and orchard were important habitats for promoting higher species richness and evenness.

Patterns of plant communities along vertical gradient in Dhauladhar Mountains in Lesser Himalayas in North-Western India.

Mountains are definitely the most rugged, yet frail resources and biodiversity-rich regions of the world. Environmental variables directly affect species composition, growth patterns, and the ecosystem resulting in a drastic change in the vegetation composition along ascending elevations. The present study investigated vegetation composition, nestedness, and turnover in plant communities along a vertical gradient (2000 to 4000m) in Dhauladhar Mountains, Lesser Himalayas, India. We determined how α-diversity pattern and nestedness-related processes or turnover (β-diversity) causes dissimilarity in plant communities' composition along the vertical gradient. Overall, 21 permanent plots (20×20m2) at every 100m interval from 2000 to 4000m were established. A sampling of shrubs and herbaceous species was done by marking sub-plots of 5×5m2 and 1×1m2, respectively, within permanent plots. We observed an inverted hump-shaped pattern for evenness index (E), a unimodal hump-shaped pattern for Shannon index (H'), Margalef's richness index, and β-Whittaker (βw) diversity, and mild-hump-shaped pattern for Simpson index (λ) across the elevational gradient. Turnover (βsim) and the nestedness-resultant component of β-diversity (βsne) significantly differed across the elevational gradient. The observed β-diversity patterns revealed that the species replacement rate was less in the mid-altitude communities as compared to lower and higher altitude communities. It was largely attributed to the ecotonic nature of mid-altitudes, which benefited mid-elevational communities rather than low or high altitude communities. Besides lower altitudes, the increased human interference has led to disturbance and subsequent homogenization of flora across the mid-altitudes. With respect to this, the present study signifies the need for preserving the mid-altitudinal communities, without undermining the importance of conserving the low and high altitude communities.

Organic Cropping Systems do not Increase Weed Seed Numbers but do Increase Weed Diversity

The influence of different cropping systems on the soil weed seed bank after the first crop rotation within a five-field crop rotation (barley undersown with red clover, red clover, winter wheat, pea, potato) in three organic (Org) and in two conventional (Conv) cropping systems was investigated. In organic systems Org I and Org II cover crops were incorporated as a source of nutrient inputs to the soil and in Org II composted cattle manure was also applied. The Org 0 acted as the organic control system without cover crops and manure. The two conventional cropping systems were treated with herbicides and fungicides and differed in fertilizer application (i.e. Conv I no fertilizer use (as control) and Conv II mineral fertilizer use). In general, the lowest number of annual weed seeds was found in system Conv I, the highest in Conv II. In organic systems with cover crops (Org I, II) there was a strong tendency for decreased weed seed numbers and increased biodiversity. The highest values of the Shannon-Wiener diversity index and Margalef richness index were in Org II system. In all systems the most abundant species in weed seed banks were Chenopodium album L. and Viola arvensis Murr.

Intestinal microbiota modulation in juvenile Pacú (Piaractus mesopotamicus) by supplementation with Pyropia columbina and β-carotene

The aim was to evaluate the effects of diet supplementation with red seaweed Pyropia columbina or β-carotene on the intestinal microbiota of juvenile Pacu (Piaractus mesopotamicus). Three hundred and fifteen fish (body weight 12.4 ± 2.8 g) were stocked in nine 300-L tanks with 35 fishes per tank and fed for 62 days with a basal feed (BG) or the same feed added with P. columbina (35 g kg−1) (AG) or supplemented with β-carotene (225 g kg−1) (β-CG). From fecal samples of three fishes slaughtered per group at 20th, 41th, and 62th days, plate counts of bacterial populations (enterobacteria, lactic acid bacteria—LAB, total aerobes, and psychrotrophs) and DGGE were made. Enterobacteria counts were lower in AG-group than the other groups throughout the experience (p = 0.016). LAB/enterobacteria ratio was greater in fishes supplemented with AG on 20th day, showing a greater amount of beneficial bacteria than non-beneficial ones. DGGE profiles resulting from the microbiota of β-CG at 62th day were clustered and separated from the rest of the profiles with a difference of 91%. Margalef richness (p = 0.049) and Shannon diversity index (p = 0.044) were lower in β-CG than in AG at 62th day. Taxonomic characterization showed the presence of three phylum: Bacteroidetes, Firmicutes, and Fusobacteria. This is the first study in which the microbiota of juvenile Pacu fed with biofunctional diets was evaluated. Future interventions that modify the bacterial ecosystem could improve the productive performance and ensure the safety of the pacu meat intended for consumption.

Structure of macroinvertebrate communities and bioassessment of water quality in the Weihe River mainstream and its typical tributaries from the northern Qinling Mountains

为摸清渭河干流及源于秦岭北麓典型支流的大型底栖动物群落特征，本研究于2017年10月和2018年5月对渭河干流及秦岭北麓5条典型支流共40个样点的大型底栖动物进行调查，并利用Margalef丰富度指数和生物指数BI生物指数对河流水质进行评价.共鉴定大型底栖动物210种，属于5门8纲75科187属.水生昆虫为优势类群，其物种数占总物种数的89.0%，且四节蜉属一种（Baetis sp.）作为绝对优势的物种出现在所有调查河流中.源于秦岭北麓的支流石头河底栖动物总密度最高（616.3 ind./m²），总生物量最大（5.265 g/m²）；而渭河干流底栖动物总密度最低（125.6 ind./m²），总生物量最小（0.289 g/m²）.水质较好的秦岭北麓典型支流底栖动物的Shannon-Wiener多样性指数、Margalef丰富度指数显著高于渭河干流，而Pielou均匀度指数在干支流间的差异性不大.通过Pearson相关分析和多元逐步回归分析得出，淤泥型底质、电导率、pH和硝酸盐氮是影响调查河流底栖动物群落特征的主导因子.丰富度指数法和生物指数法水质评价结果分别显示，渭河干流有73.3%和80.0%的采样点呈中度-重度污染状态，秦岭北麓典型支流有80.0%和68.0%的采样点呈无污染-轻度污染状态.本研究可为渭河流域生态管理与保护提供基础的数据支撑.;For exploring the macroinvertebrate community characteristics of the Weihe River mainstream and its typical tributaries originating from the northern Qinling Mountains, investigation of water environment and macroinvertebrates was conducted in 40 sampling sites in October 2017 and May 2018. Furthermore, Margalef richness and biological index (BI) biological indices were used to assess the water quality of studied rivers. Altogether 210 macroinvertebrates species were identified, belonging to 187 genera, 75 families, 8 classes and 5 phyla. Aquatic insects were the dominant group, accounting for 89.0% of the total species number, and the Baetis sp. was the dominant species in all studied rivers. The tributary Shitou River, had the highest values of total density(616.3 ind./m²), and the highest total biomass(5.265 g/m²). Whereas the total density (125.6 ind./m²) and total biomass (0.289 g/m²) of macroinvertebrates were both lowest in the Weihe River mainstream. The Shannon-Wiener diversity index(H')and Margalef richness index(R)of five typical tributaries were characterized by good water quality and significantly higher than those of the Weihe River mainstream, whereas the Pielou evenness index(J)showed insignificant difference between mainstream and tributaries. Pearson correlation analysis and the multiple linear regression analysis showed that “Silt plus clay” type substrate, conductivity, pH and nitrate nitrogen were the primary environment factors effecting the macroinvertebrate community characteristics in studied rivers. According to the water quality evaluation results of the richness index and the BI method, 73.3% and 80.0% of the mainstream sites were identified as moderately to heavily polluted, but 80.0% and 68.0% of tributary sites were identified as non-polluted to slightly polluted. This study can provide basic data supports for ecological management and protection in the Weihe River Basin.

Herpetofauna community structure and distribution of Watu Joglo cave area, Gunung Kidul, Special Region of Yogyakarta

Watu Joglo is one of the caves located in the row of the Sewu mountains, Gunung Kidul, Special Regency of Yogyakarta. Watu Joglo has various suitable microhabitats for herpetofauna. So far, the study about herpetofauna’s community structure and distribution has not been carried out in Watu Joglo. This study aimed to study and map the diversity, richness, evenness, and distribution of herpetofauna in Watu Joglo. Herpetofauna’s data sampling was carried out for three days. The study was conducted on 6-8 April 2018. The data of herpetofauna community were analyzed with Shannon-Wiener diversity index, Margalef richness index, and Pielou Evenness Index. The data of herpetofauna distribution were mapped and analyzed with Avenza and ArcGis. Based on the research conducted, we found 11 species of herpetofauna which consisted of five species from Ordo Anura, four species from Subordo Lacertilia, and two species from Subordo Serpentes. Herpetofauna in Watu Joglo was widely distributed around the river. According to diversity analysis, Watu Joglo has moderate diversity index, 1.667. Besides, Watu Joglo has high evenness index which is 0.85 but low richness index which is 2.83.