scholarly journals Variation of the community structure of terrestrial gastropods in different plant associations from the Coatán River watershed, southeastern Chiapas, Mexico

2020 ◽  
pp. 1-16
Author(s):  
Edgar Tovar-Juárez ◽  
Victor Iván López-Paz ◽  
Edna Naranjo-García ◽  
Yaneth Estrada-Santos ◽  
Pedro Martín Negrete-Moreno ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Environmental Variables ◽  
Plant Association ◽  
River Watershed ◽  
Terrestrial Gastropods ◽  
Plant Associations ◽  
Secondary Vegetation ◽  
Ecosystem Indicators ◽  
Low Diversity ◽  
Original Plant

The Gastropoda class is the only one on Mollusca phylum to have terrestrial representatives. These organisms are used as ecosystem indicators due to being closely related to environmental variables such as soil and relative humidity, pH, temperature, and plant association, variables sensitive to habitat alteration. The original ecosystems of the watersheds in the Soconusco, Chiapas, Mexico are suitable for the presence of terrestrial gastropods, however, has experimented severe loss of the original plant association, the objective of the research was to determine the diversity of terrestrial gastropods and its changes in the Coatán River watershed. Sampling was carried out at three sites according to their plant association (primary vegetation, secondary vegetation, and crops), within three zones of the watershed (upper, middle, and lower zone). A total of 342 organisms was obtained and classified into 16 families, 29 genera and 43 species, of these totals, 89% were Heterobranchia and 11% Caenogastropoda-Neritimorpha, which are mainly present in the middle zone. Five species are new records for Mexico and 10 species for Chiapas and extend the range distribution of several Central America species. The results of changes in diversity and abundance occurred at zone level and were influenced by environmental variables, mainly relative humidity and tree covered plant association. Low diversity patterns were related to high environmental temperature and low relative humidity, both related to the degree of disturbance and loss plant covered. The human activity in the Coatán watershed has an adverse effect on terrestrial gastropod diversity.

Recent Rapid Climate Changes in Antarctic and their Influence on Low Diversity Ecosystems

2010 ◽  
Vol 17 (1) ◽  
pp. 17-30 ◽  
Author(s):  
Katarzyna J. Chwedorzewska
Keyword(s):  
Environmental Variables ◽  
Climate Changes ◽  
Biological Significance ◽  
Global Changes ◽  
Factors Affecting ◽  
Low Diversity ◽  
Main Factors ◽  
The Antarctic ◽  
High Diversity ◽  
Temperature Water

ABSTRACTThe geographic position, astronomic factors (e.g. the Earth’s maximum distance from the Sun during winter), ice cover and altitude are the main factors affecting the climate of the Antarctic, which is the coldest place on Earth. Parts of Antarctica are facing the most rapid rates of anthropogenic climate change currently seen on the planet. Climate changes are occurring throughout Antarctica, affecting three major groups of environmental variables of considerable biological significance: temperature, water, UV-B radiation.Low diversity ecosystems are expected to be more vulnerable to global changes than high diversity ecosystems

scholarly journals Transport of broilers: load microclimate during Brazilian summer

2014 ◽  
Vol 34 (3) ◽  
pp. 405-412 ◽  
Author(s):  
José A. D. Barbosa Filho ◽  
Marília L. V. Queiroz ◽  
Daniel de F. Brasil ◽  
Frederico M. C. Vieira ◽  
Iran J. O. Silva
Keyword(s):  
Relative Humidity ◽  
Ordinary Kriging ◽  
Environmental Variables ◽  
Critical Period ◽  
Continuous Monitoring ◽  
Kriging Method ◽  
Comfort Index ◽  
Data Loggers

The objective of this study was to characterize the microclimatic profile of broiler transport trucks under commercial conditions, in the summer, by continuous monitoring of environmental variables (temperature and air relative humidity). Three loads were monitored from farm to slaughterhouse, considering factors such as distance and day periods (morning, afternoon, and night). To obtain the profile of the environmental variables during journey, data loggers, that determined the microclimate to which birds were submitted, were installed in the trucks; data loggers also allowed visualization of the Enthalpy Comfort Index (ECI) so that load regions could be classified according to heat comfort limits for 6-week old poultries. Temperature, relative humidity, and ECI in the truck were analyzed, using geostatistics, by the ordinary kriging method. The afternoon was the most critical period, and truck central and rear regions were most problematic for chickens, thus most susceptible to losses.

ETUDE AGRO-ECOLOGIQUE DANS LE COMTE DE RIVIERE-DU-LOUP: ASPECT ECOLOGIQUE

1978 ◽  
Vol 58 (1) ◽  
pp. 117-128
Author(s):  
J. M. DESCHENES ◽  
J. C. ST-PIERRE
Keyword(s):  
Ecological Study ◽  
Ecological Factors ◽  
Vegetation Changes ◽  
Plant Association ◽  
Vegetation Survey ◽  
Land Utilization ◽  
Red Fescue ◽  
Plant Associations ◽  
Ecological Habitat ◽  
Successional Stages

Intensive studies of soil and vegetation were performed in Rivière-du-Loup County to identify various plant associations of meadows and pastures, describe the successional trends of each ecological habitat and establish a relationship between plant associations and various environmental factors. After vegetation survey and analysis, four plant associations and their successional trends were described. Each plant association was identified by the dominant species at the most advanced stage of secondary succession: (1) red fescue-bent grass association, (2) red fescue-Lindberg’s plume moss association, (3) bent grass–red fescue association, and (4) poverty grass–mouse-eared hawkweed association. All four plant associations were distributed in space according to the physiography and nature of the soils. Vegetation was highly influenced by age of sites. Young meadows and pastures were dominanted by timothy, red top, white clover and Canada bluegrass. Red fescue was very important on all 10 yr-old sites and remained so in all successional stages except in bent grass–red fescue and poverty grass–mouse-eared hawkweed associations. Vegetation changes with age depended on both ecological factors and land utilization. The results suggest that intensive soil studies and a rapid survey of vegetation would have provided results very similar to those obtained by a very detailed ecological study.

Plant diversity, composition, and rarity in the southern boreal peatlands of Manitoba, Canada

2006 ◽  
Vol 84 (6) ◽  
pp. 940-955 ◽  
Author(s):  
David A. Locky ◽  
Suzanne E. Bayley
Keyword(s):  
Plant Diversity ◽  
Environmental Variables ◽  
Vascular Plants ◽  
Black Spruce ◽  
General Pattern ◽  
Boreal Peatlands ◽  
Environmental Extremes ◽  
Low Diversity ◽  
Total Diversity ◽  
High Diversity

Plant diversity and rarity have been relatively well studied for bryophytes in Canadian western boreal peatlands, but little information exists for vascular plants. Diversity, community composition, and rarity of bryophytes and vascular plants were determined and relationships examined among these and environmental variables in five peatland types at Duck Mountain, Manitoba: wooded bogs, black spruce swamps, wooded moderate-rich fens, open moderate-rich fens, and open extreme-rich fens. Total diversity was 298 species comprising 86 bryophytes and 212 vascular plants. Mean diversity followed a unimodal distribution over a bog – rich fen gradient. Wooded moderate-rich fens (59.0) and black spruce swamps (53.4) had the highest mean diversity, whereas wooded bogs (32.3) and open extreme-rich fens (34.7) had the lowest mean diversity. Occurrences of locally rare species followed the same general pattern, and provincially rare vascular plants were found primarily in wooded moderate-rich fens and black spruce swamps and were mostly orchids. Reasons for these patterns are complex, but high diversity appears to be related to high habitat heterogeneity and moderate environmental variables, e.g., pH and alkalinity, and low diversity appears to be related to environmental extremes, e.g., pH and alkalinity. Boreal wooded moderate-rich fens and black spruce swamps have comparatively high plant diversity and rarity and require consideration if the focus is biodiversity conservation. This will become increasingly important in landscapes where development pressures are high.

scholarly journals Model Simulation of Cucumber Yield and Microclimate Analysis in a Semi-closed Greenhouse in China

HortScience ◽  
2019 ◽  
Vol 54 (3) ◽  
pp. 547-554 ◽  
Author(s):  
Xiaotao Ding ◽  
Yuping Jiang ◽  
Dafeng Hui ◽  
Lizhong He ◽  
Danfeng Huang ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Environmental Variables ◽  
Regression Models ◽  
Model Simulation ◽  
High Yield ◽  
Total Radiation ◽  
Greenhouse Climate ◽  
Yield Forecast ◽  
Cucumber Yield

Adequate greenhouse environmental management is very important for improving resource use efficiency and increasing vegetable yield. The objective of this study was to explore suitable climate and cultivation management for cucumber to achieve high yield and build optimal yield models in semi-closed greenhouses. A fruit cucumber cultivar Deltastar was grown over 4 years in greenhouse and weekly data of yields (mean, highest and lowest) and environmental variables, including total radiation, air temperature, relative humidity, and carbon dioxide (CO2) concentration were collected. Regression analyses were applied to develop the relationships and build best regression models of yields with environmental variables using the first 2 years of data. Data collected in years 3 and 4 were used for model validation. Results showed that total radiation, nutrient, temperature, CO2 concentration, and average nighttime relative humidity had significant correlations with cucumber yields. The best regression models fit the mean, lowest, and highest yields very well with R2 values of 0.67, 0.66, and 0.64, respectively. Total radiation and air temperature had the most significant contributions to the variations of the yields. Our results of this study provide useful information for improving greenhouse climate management and yield forecast in semi-closed greenhouses.

scholarly journals Ramondo-Ostryetum carpinifoliae – a new association from the hop-hornbeam forests of the Sharri Mountains, Kosovo

Hacquetia ◽  
2019 ◽  
Vol 18 (2) ◽  
pp. 323-336
Author(s):  
Naim Berisha ◽  
Fadil Millaku ◽  
Bekim Gashi ◽  
Vlado Matevski
Keyword(s):  
Plant Community ◽  
Plant Communities ◽  
Plant Association ◽  
Limestone Habitat ◽  
Plant Associations ◽  
New Association ◽  
Ostrya Carpinifolia ◽  
Ramonda Myconi

Abstract In Europe, the genus Ramonda is represented with three species: Ramonda nathaliae, Ramonda serbica and Ramonda myconi. The first two are endemic Balkan species that are distributed also in Kosovo. These species grow in limestone as well as serpentine substrates, forming chasmophytic vegetation. The species Ramonda nathaliae is found in Macedonia, Greece, Serbia and in two localities in Kosovo, in the Sharri Mountains (Luboten and Gotovushë). R. nathaliae forms the following plant associations in the serpentines of Macedonia: Asplenio­Ramondetum nathaliae and Scorzonero-Ramondetum nathaliae, and the Achilleo­Ramondetum nathaliae in limestone substrates. Ostrya carpinifolia is charateristic species in Querco pubescentis-Ostryetum carpinifoliae, Ostryo-Fagetum, Querco-Ostryetum carpinifoliae and Corylo colurnae-Ostryetum carpinifoliae. This paper presents plant communities of Ramonda nathaliae and Ostrya carpinifolia in a limestone habitat, where the proposed new plant association named Ramondo­Ostryetum carpinifoliae ass. nova. is described. This plant community belongs to the class Quercetea pubescentis, order Quercetalia pubescenti­petraeae and alliance Fraxino orni­Ostryion. It was found and described on the limestone substrate on Mt. Luboteni (at 960–982 m a.s.l.).

scholarly journals Plant associations for three sawfly species (Hymenoptera, Tenthredinidae) in the Pacific Northwest

2019 ◽  
Vol 74 ◽  
pp. 27-33
Author(s):  
Quinlyn Baine ◽  
Chris Looney
Keyword(s):  
Pacific Northwest ◽  
Plant Association ◽  
Plant Associations ◽  
The Pacific

Plant associations are newly recorded for three tenthredinid species in the Pacific Northwest. A single Monardis pulla D.R. Smith, 1969 emerged from a chamber inside a cynipid gall on Rosa nutkana C. Presl. (Rosaceae). This is the first plant association record for M. pulla. Two Aphilodyctium fidum (Cresson, 1880) emerged from a stem and cynipid gall of Rosa rugibinosa Linnaeus, 1758, respectively. Several Rhogogaster lateraria (Cresson, 1880) eggs were discovered on Castilleja sp., which has no previously recorded sawfly associations.

scholarly journals Association distribution characteristics of natural and artificial Larix gmelinii forests along environmental gradients in northeast China

2019 ◽  
Author(s):  
Xiaohang Bai ◽  
Jinghua Yu ◽  
Shusheng Yuan ◽  
Yihong Tan
Keyword(s):  
Species Diversity ◽  
Northeast China ◽  
Larix Gmelinii ◽  
Annual Precipitation ◽  
Environmental Drivers ◽  
Slope Aspect ◽  
Scientific Management ◽  
Plant Association ◽  
Natural Forests ◽  
Plant Associations

Abstract Background: Larix gmelinii forest is one of coniferous forests in cold-temperate zone, which is a vital part of national strategic landscape of ecological security of China. Plant association distribution is different in natural and artificial Larix gmelinii forests, meanwhile, determining mechanisms in typical associations of Larix gmelinii forests still need to be explored. The study focused on which environmental factors actuated association distribution of natural and artificial Larix gmelinii forests in northeast China. Two-way indicator species analysis (TWINSPAN) and canonical correspondence analysis (CCA) were used to classify plant associations and explored the relationship between species and environment. Results: All the plots (n=175, size=30 m×30 m) of Larix gmelinii forests were classified into 6 plant associations by TWINSPAN. Species diversity in natural forests were higher than that in artificial forests. Ass.III and Ass.IV only appeared in natural forests, meanwhile, Ass.VI only appeared in artificial forests. The primary environmental drivers of species diversity patterns in natural forests were annual mean temperature, followed by annual precipitation, elevation, slope aspect, and canopy density. However, elevation and annual precipitation had strong effects in determining association distribution in artificial forests. Conclusions: Plant association distribution showed habitat preferences, besides, natural forests had higher species diversity and more resistance than artificial forests. The study can be used as a reference for Larix gmelinii forest ecosystem protection in northeast China and a theoretical basis for scientific management in similar areas.

scholarly journals Long-term weather, hydrometric, and water chemistry datasets in high-temporal resolution at the La Salle River watershed in Manitoba, Canada

2017 ◽  
Author(s):  
Marcos R. C. Cordeiro ◽  
Jason A. Vanrobaeys ◽  
Henry F. Wilson
Keyword(s):  
Wind Speed ◽  
Relative Humidity ◽  
Solar Radiation ◽  
Water Chemistry ◽  
Temporal Resolution ◽  
Time Step ◽  
Canadian Prairies ◽  
River Watershed ◽  
Stream Discharge

Abstract. Lack of long-term datasets in fine temporal resolution hinders environmental studies and modelling efforts; to address this issue in the La Salle River watershed, in Canada, long-term weather (1990–2013), hydrometric (1990–2013 except years with no or poor data), and water chemistry (2009–2013) datasets were developed. The weather variables consisted of temperature, relative humidity, wind speed, solar radiation, and precipitation in an hourly time-step, which is required for physically-based modelling. The only hydrometric variable included in the dataset was stream discharge in a daily time-step, which is the usual time-frame for summarizing the results of long-term studies. The water chemistry data consisted of total nitrogen (TN), total dissolved nitrogen (TDN), total phosphorus (TP) and total dissolved phosphorus (TDP). Samples were collected weekly during the open water season at the same site as they hydrometric gauging station (05OG008) starting in August 2009 until October 2012 with some gaps (i.e. Fall 2011, Spring 2012, September 2012). In 2013 the frequency of sampling was increased to daily or sub-daily during high stream discharge and weekly during low stream discharge. An overview of the data indicates that values and trends are within ranges reported in the literature for the region. Mean annual, winter, and summer temperatures were 3.5 °C–10.7 °C and 17.2 °C, respectively. Annual relative humidity averaged 73.1 % but tended to be higher and more homogenous in cold seasons. Wind speed was very similar over the different seasons with annual average of 4.3 m/s. Solar radiation followed the typical curve reported for western Canada, with peak daily average values around 250 W/m2 in July. The precipitation records were mostly comprised of dry hours and the characteristic precipitation pattern of the Canadian Prairies with high frequency of small precipitation events as observed, with 75.3 % of the hourly precipitation being equal or less than 2 mm/h. The hydrometric characteristics of the dataset were also typical of the Canadian Prairies; the average peak discharge over the entire period was larger in April (2.3 m3/s) due to large amounts of snowmelt runoff. The average concentrations of TN, TDN, TP and TDP of 1.54, 1.35, 0.56, and 0.49 mg/L, respectively, were in agreement with values found in previous studies at the same location. The datasets for weather (https://doi.org/10.23684/ODI-2017-00957), discharge (https://doi.org/10.23684/ODI-2017-00959) and water chemistry (https://doi.org/10.23684/ODI-2017-00958) are accessible through the Government of Canada's Open Data portal (http://open.canada.ca).

Gastrointestinal parasitic infections in cattle and swamp buffalo of Guwahati, Assam, India

2018 ◽  
Author(s):  
M. Das ◽  
D. K. Deka ◽  
A. K. Sarmah ◽  
P. C. Sarmah ◽  
S. Islam
Keyword(s):  
Relative Humidity ◽  
Environmental Variables ◽  
Fasciola Gigantica ◽  
Total Variance ◽  
Parasitic Infections ◽  
Mixed Infections ◽  
Multiple Linear Regressions ◽  
Toxocara Vitulorum ◽  
Swamp Buffalo ◽  
Linear Regressions

The objective of the present study was to determine the prevalence of gastrointestinal (G.I.) parasitic infections in cattle and swamp buffalo of Assam, India. A total of 3597 fecal samples of cattle (2339) and buffaloes (1258) were examined for presence of parasitic infections. Examinations revealed an overall prevalence of 58.35% and 29.80% infections in cattle and buffalo, respectively. In cattle, Strongyle sp. (18.76%) was predominant followed by Eimeria sp. (11.97%), Amphistome sp. (8.72%), Strongyloides sp. (3.76%), Moniezia sp. (2.65%), Toxocara vitulorum (1.32%), Buxtonella sulcata (0.81%), Trichuris sp. (0.72%), Fasciola gigantica (0.47%) and Bunostomum sp. (0.38%). In buffalo, Amphistome sp. (8.90%) was predominant followed by T. vitulorum (5.64%), Strongyle sp. (5%), Eimeria sp. (4.53%), Strongyloides sp. (1.35%) and Trichuris sp. (0.47%). Mixed infections with more than one species were recorded in 8.76% and 3.89% cattle and buffalo, respectively. The egg per gram (EPG) of feces in cattle and buffalo was 582.44±8.13 and 475.86±11.29, respectively while oocyst per gram (OPG) of feces was 425.00±20.37 and 251.75±22.35, respectively. Correlation of rainfall and temperature with EPG/OPG of cattle and buffalo was highly significant (P less than 0.01) while correlation of relative humidity (Av.) with EPG of cattle and buffalo was significant (P less than 0.05). Multiple linear regressions explained about 98.10% of total variance in EPG of cattle with environmental variables. 89.10% of total variance in EPG of buffalo was explained in multiple linear regressions due to environmental variables. This shows that the climate in this region is exclusively conducive for the development and propagation of parasites.

Sign in / Sign up

Export Citation Format

Share Document