Seasonal changes in the intertidal algal communities of Sanya Bay (Hainan Island, China)

2014 ◽  
Vol 94 (5) ◽  
pp. 879-893 ◽  
Author(s):  
Eduard A. Titlyanov ◽  
Tamara V. Titlyanova ◽  
Xiubao Li ◽  
Gayle I. Hansen ◽  
Hui Huang
Keyword(s):  
Red Algae ◽  
Intertidal Zone ◽  
Rainy Season ◽  
Dominant Species ◽  
Hainan Island ◽  
Dry Season ◽  
Splash Zone ◽  
Intertidal Zones ◽  
Species Numbers ◽  
Sanya Bay

A floristic study of marine macrophytic algae and Cyanobacteria in the splash and intertidal zones at Luhuitou reef, Sanya Bay, Hainan Island, China, was conducted during the rainy and dry seasons of 2008−2012 utilizing 148 of the most common species. Macrophytic algal diversity increased from the splash zone to the low intertidal zone, while cyanobacterial diversity decreased. In the upper and middle intertidal zones, the dominant species (primarily highly productive ephemerals) changed frequently throughout each year. In the low intertidal zone, the dominant species (mainly annual fleshy, foliose and coriaceous forms) also changed. In the dry season, species numbers were 33% higher than in the rainy season. During the rainy season, Cyanobacteria dominated the splash zone, while green and red algae dominated in increasing numbers from the upper to the low intertidal zones. During the dry season the splash zone was devoid of all macrophytic algae, and only one species of Cyanobacteria survived. In the upper intertidal, Cyanobacteria and red algae prevailed, while in the mid and low zones, red and green algae were the most diverse. In spite of heavy pollution in Sanya Bay, there was no evidence of dramatic changes in species numbers or composition, and the marine flora was similar to that of unpolluted regions in the Indo-Pacific.

scholarly journals Seasonal Changes in the Intertidal and Subtidal Algal Communities of Extremely and Moderately Polluted Coastal Regions of Sanya Bay (Hainan Island, China)

2019 ◽  
Vol 7 (4) ◽  
pp. 93
Author(s):  
Eduard A. Titlyanov ◽  
Tamara V. Titlyanova ◽  
Hui Huang ◽  
Anna V. Scriptsova ◽  
Huili Xu ◽  
...  
Keyword(s):  
Species Diversity ◽  
Seasonal Changes ◽  
Rainy Season ◽  
Hainan Island ◽  
Dry Season ◽  
Polluted Area ◽  
Algal Communities ◽  
Intertidal Zones ◽  
Polluted Sites ◽  
Sanya Bay

At the end of the rainy season in 2016 and at the end of the dry season in 2017, we conducted a floristic study of marine macrophytic algae in the intertidal and subtidal zones in moderately and heavily polluted areas at Luhuitou reef, Sanya Bay, Hainan Island, China. A total of 109 species of marine macrophytes were found during these samplings. At the end of the rainy season, 72 species of macrophytes (50% reds, 19% browns, and 31% greens) were found. At the end of the dry season, we found and identified 92 species of macrophytes (46% reds, 20% browns, and 34% greens). Seasonal changes in species diversity, species composition, and the structure of algal communities at differently polluted sites exhibited common features as well as specific characteristics. By the end of the dry season, the diversity of macroalgal species was increased, and the composition of dominant and accompanying species of macrophytes in polydominant communities was changed in moderately and heavily polluted areas. Seasonal changes in the marine flora of differently polluted areas were characterized by specific features as follows: Less changes in species diversity of heavily polluted area compared with moderately polluted area during the change from the rainy season to the dry season; significant increase in the biomass of green algae and their projective coverage in the middle and low intertidal zones of heavily polluted sites in the dry season; and the increase in the numbers of mono- and bidominant communities in the middle and low intertidal zones of heavily polluted sites by the end of the dry season.

scholarly journals The diversity of intertidal fish in Sundak Beach, Yogyakarta, Indonesia, during dry and rainy seasons

2020 ◽  
Vol 147 ◽  
pp. 02020
Author(s):  
Ratih Ida Adharini ◽  
Namastra Probosunu ◽  
Atika Arifati ◽  
Tika Drastiana ◽  
Fitriana C. Rusnasari
Keyword(s):  
Intertidal Zone ◽  
Rainy Season ◽  
Good Condition ◽  
Dry Season ◽  
Quality Data ◽  
Water Quality Data ◽  
Transition Area ◽  
Fish Samples ◽  
Low Diversity ◽  
Dry And Rainy Seasons

The intertidal zone is a transition area between sea and land with unique characteristics. This research aimed to determine the diversity and types of fish in the intertidal zone of Sundak Beach, Yogyakarta, Indonesia. This research was conducted in December 2016–September 2017 along the intertidal zone of Sundak Beach. Fish samples were collected by fishermen twice a month using a hand net and hand line in an area of 22,000 m2 by random sampling. Water quality data included air and water temperatures, pH, salinity, tides, rainfall intensity, and substratum. Fish samples were identified, and the total length and weight were measured. Results showed that carnivores and herbivores were dominant during the rainy season, whereas carnivores and omnivores were dominant during the dry season. Total of 179 fish, which were grouped into 18 families and 31 species. The diversity species index was 1.067 (intermediate diversity) during the rainy season but 0.19 (low diversity) during the dry season. The dominancy index was low (0.11–0.34) during the dry season, whereas during the rainy season was higher (0.18–0.72). The study concluded that the intertidal zone of Sundak Beach has a good condition as nursery, feeding, and spawning grounds for fishes.

scholarly journals Population Dynamics of Aedes aegypti and Aedes albopictus in Two Rural Villages in Southern Mexico: Baseline Data for an Evaluation of the Sterile Insect Technique

Insects ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 58
Author(s):  
Carlos F. Marina ◽  
J. Guillermo Bond ◽  
Kenia Hernández-Arriaga ◽  
Javier Valle ◽  
Armando Ulloa ◽  
...  
Keyword(s):  
Aedes Aegypti ◽  
Aedes Albopictus ◽  
Rainy Season ◽  
Sterile Insect Technique ◽  
Dominant Species ◽  
Dry Season ◽  
Population Fluctuations ◽  
Southern Mexico ◽  
Rural Villages ◽  
The Village

Indoor and outdoor ovitraps were placed in 15 randomly selected houses in two rural villages in Chiapas, southern Mexico. In addition, ovitraps were placed in five transects surrounding each village, with three traps per transect, one at the edge, one at 50 m, and another at 100 m from the edge of the village. All traps were inspected weekly. A transect with eight traps along a road between the two villages was also included. Population fluctuations of Aedes aegypti and Ae. albopictus were examined during 2016–2018 by counting egg numbers. A higher number of Aedes spp. eggs was recorded at Hidalgo village with 257,712 eggs (60.9%), of which 58.1% were present in outdoor ovitraps and 41.9% in indoor ovitraps, compared with 165,623 eggs (39.1%) collected in the village of Río Florido, 49.0% in outdoor and 51.0% in indoor ovitraps. A total of 84,047 eggs was collected from ovitraps placed along transects around Río Florido, compared to 67,542 eggs recorded from transects around Hidalgo. Fluctuations in egg counts were associated with annual variation in precipitation, with 2.3 to 3.2-fold more eggs collected from ovitraps placed in houses and 4.8 to 5.1-fold more eggs in ovitraps from the surrounding transects during the rainy season than in the dry season, respectively. Aedes aegypti was the dominant species during the dry season and at the start of the rainy season in both villages. Aedes albopictus populations were lower for most of the dry season, but increased during the rainy season and predominated at the end of the rainy season in both villages. Aedes albopictus was also the dominant species in the zones surrounding both villages. The numbers of eggs collected from intradomiciliary ovitraps were strongly correlated with the numbers of eggs in peridomiciliary ovitraps in both Río Florido (R2adj = 0.92) and Hidalgo (R2adj = 0.94), suggesting that peridomiciliary sampling could provide an accurate estimate of intradomiciliary oviposition by Aedes spp. in future studies in these villages. We conclude that the feasibility of sterile insect technique (SIT)-based program of vector control could be evaluated in the isolated Ae. aegypti populations in the rural villages of our baseline study.

scholarly journals Distribuição e abundância de isópodes gigantes Bathynomus (Crustacea, Isopoda, Cirolanidae) da Plataforma Continental Amazônica

2020 ◽  
Vol 9 (8) ◽  
pp. e974986843
Author(s):  
Katia Cristina de Araújo Silva ◽  
Fernando Araújo Abrunhosa ◽  
Rafael Anaisce das Chagas ◽  
Marko Herrmann ◽  
Israel Hidenburgo Aniceto Cintra
Keyword(s):  
Continental Shelf ◽  
Rainy Season ◽  
Dominant Species ◽  
Dry Season ◽  
Exclusive Economic Zone ◽  
Community Based ◽  
Southern Sector ◽  
Economic Zone ◽  
Northern Sector

The present study focuses on the distribution and abundance of the giant isopod community, based on specimens collected using the bottom shrimp trawling on the Amazon continental shelf during fishery surveys, at depths between 81 m and 626 m, conducted during the REVIZEE/Score-North Program between 1996 and 1998. The study area is located within the exclusive economic zone of Brazil, between the States of Amapá and Pará. In total, 170 specimens were collected, distributed in the two species Bathynomus giganteus (n = 49) and Bathynomus miyarei (n = 121), in which 54% of the material were collected in the northern and 46% in the southern sector of the study area. B. miyarei was considered to be the dominant species in both sectors, whereas B. giganteus was uncommon in the northern sector, but abundant in the southern sector.  Both species preferred gravelly bottoms in the northern sector, and gravelly sand in the southern sector and were more abundant during the dry season in the northern sector, but during the rainy season in the southern sector. The smallest female B. giganteus was collected in the northern sector, and the largest in the southern sector, whereas both the largest and the smallest female B. miyarei were captured in the southern sector. All the male specimens collected in this study were captured in the northern sector.

Inventory change (1990s–2010s) in the marine flora of Sanya Bay (Hainan Island, China)

2014 ◽  
Vol 95 (3) ◽  
pp. 461-470 ◽  
Author(s):  
Eduard A. Titlyanov ◽  
Tamara V. Titlyanova ◽  
Oksana S. Belous ◽  
Tatyana L. Kalita
Keyword(s):  
Red Algae ◽  
Marine Algae ◽  
High Surface ◽  
Volume Ratio ◽  
Floristic Composition ◽  
Hainan Island ◽  
Urban Sewage ◽  
The Past ◽  
Sanya Bay ◽  
Marine Flora

Sanya Bay lies at the southern part of Hainan Island, 18°15′N 109°28′E. The seawater in the bay has been catastrophically polluted during the past two decades with urban sewage from the rapidly developing Sanya City. The marine flora research in Sanya Bay was started at the beginning of the 1930s and the most detailed studies were performed by two German-Chinese expeditions in 1990 (October–December) and in 1992 (March–April). In April, October, November and December 2008–2010 the marine flora of Sanya Bay was studied by the authors at three localities: Luhuitou Peninsula, Xiaodong Hai and Dadong Hai. Marine algae were sampled in the intertidal and upper subtidal zones (to 4–5 m depth). The list of species (including varieties and forms) of the marine algae for Sanya Bay sampled during the period from 2008 to 2010 is compared with those collected at the same localities in 1990/1992. Comparative analysis of the floristic composition of the marine red, brown and green algae (found during different time periods) revealed that considerable changes have taken place between 1990/1992 and 2008–2010 at Sanya Bay. There was an increase in filamentous, tubular and fine blade-like green and red algae (mainly epiphytes with a high surface to volume ratio) and a displacement of upright-growing fleshy, foliose and other large green, brown and red algae with a low surface to volume ratio. It is assumed that the changes reflect mainly increased pollution by urban sewage and mariculture pond wastes and probably by coral bleaching events of 1998.

STUDI BIONOMIK VEKTOR MALARIA DI KECAMATAN KALIBAWANG, KULONPROGO

2018 ◽  
Vol 4 (2) ◽  
Author(s):  
Sardjito Eko Windarso dkk
Keyword(s):  
Land Use ◽  
Malaria Vector ◽  
Rainy Season ◽  
Dry Season ◽  
Physical Factors ◽  
Mosquito Vector ◽  
Anopheles Species ◽  
Commercial Farming ◽  
Study Results ◽  
Dry And Rainy Seasons

The increasing of malaria cases in recent years at Kecamatan Kalibawang has been suspected correspond with the conversion of farming land-use which initiated in 1993. Four years after the natural vegetation in this area were changed become cocoa and coffee commercial farming estates, the number of malaria cases in 1997 rose more than six times, and in 2000 it reached 6085. This study were aimed to observe whether there were any differences in density and diversity of Anopheles as malaria vector between the cocoa and mix farming during dry and rainy seasons. The results of the study are useful for considering the appropriate methods, times and places for mosquito vector controlling. The study activities comprised of collecting Anopheles as well as identifying the species to determine the density and diversity of the malaria vector. Both activities were held four weeks in dry season and four weeks in rainy season. The mea-surement of physical factors such as temperature, humidity and rainfall were also conducted to support the study results. Four dusuns which meet the criteria and had the highest malaria cases were selected as study location. Descriptively, the results shows that the number of collected Anopheles in cocoa farming were higher compared with those in mix horticultural farming; and the number of Anopheles species identifi ed in cocoa farming were also more varied than those in the mix horticultural farming.Key words: bionomik vektor malaria, anopheles,

scholarly journals Understanding variability in greenhouse gas emission estimates of smallholder dairy farms in Indonesia

2021 ◽  
Author(s):  
Titis Apdini ◽  
Windi Al Zahra ◽  
Simon J. Oosting ◽  
Imke J. M. de Boer ◽  
Marion de Vries ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Rainy Season ◽  
Greenhouse Gas Emission ◽  
Dairy Farms ◽  
Dry Season ◽  
Enteric Fermentation ◽  
Tropical Regions ◽  
Population Mean ◽  
Smallholder Dairy ◽  
Smallholder Dairy Farms

Abstract Purpose Life cycle assessment studies on smallholder farms in tropical regions generally use data that is collected at one moment in time, which could hamper assessment of the exact situation. We assessed seasonal differences in greenhouse gas emissions (GHGEs) from Indonesian dairy farms by means of longitudinal observations and evaluated the implications of number of farm visits on the variance of the estimated GHGE per kg milk (GHGEI) for a single farm, and the population mean. Methods An LCA study was done on 32 smallholder dairy farms in the Lembang district area, West Java, Indonesia. Farm visits (FVs) were performed every 2 months throughout 1 year: FV1–FV3 (rainy season) and FV4–FV6 (dry season). GHGEs were assessed for all processes up to the farm-gate, including upstream processes (production and transportation of feed, fertiliser, fuel and electricity) and on-farm processes (keeping animals, manure management and forage cultivation). We compared means of GHGE per unit of fat-and-protein-corrected milk (FPCM) produced in the rainy and the dry season. We evaluated the implication of number of farm visits on the variance of the estimated GHGEI, and on the variance of GHGE from different processes. Results and discussion GHGEI was higher in the rainy (1.32 kg CO2-eq kg−1 FPCM) than in the dry (0.91 kg CO2-eq kg−1 FPCM) season (P < 0.05). The between farm variance was 0.025 kg CO2-eq kg−1 FPCM in both seasons. The within farm variance in the estimate for the single farm mean decreased from 0.69 (1 visit) to 0.027 (26 visits) kg CO2-eq kg−1 FPCM (rainy season), and from 0.32 to 0.012 kg CO2-eq kg−1 FPCM (dry season). The within farm variance in the estimate for the population mean was 0.02 (rainy) and 0.01 (dry) kg CO2-eq kg−1 FPCM (1 visit), and decreased with an increase in farm visits. Forage cultivation was the main source of between farm variance, enteric fermentation the main source of within farm variance. Conclusions The estimated GHGEI was significantly higher in the rainy than in the dry season. The main contribution to variability in GHGEI is due to variation between observations from visits to the same farm. This source of variability can be reduced by increasing the number of visits per farm. Estimates for variation within and between farms enable a more informed decision about the data collection procedure.

scholarly journals Directional Distance Function Technical Efficiency of Chili Production in Thailand

2021 ◽  
Vol 13 (2) ◽  
pp. 741
Author(s):  
Wirat Krasachat ◽  
Suthathip Yaisawarng
Keyword(s):  
Distance Function ◽  
Rainy Season ◽  
Sample Selection ◽  
Agricultural Practices ◽  
Directional Distance Function ◽  
Dry Season ◽  
Small Samples ◽  
Function Technique ◽  
Security Problem ◽  
Gap Technology

To overcome the challenging food safety and security problem, in 2003, the Thai government initiated ‘Good Agricultural Practices’ (GAP) technology. This paper used a sample of 107 small chili farms from the Chiyaphoom province for the 2012 crop year, and data envelopment analysis (DEA) meta-frontier directional distance function technique to answer two questions: (1) Are GAP-adopting farms, on average, more efficient than conventional farms? (2) Does access to GAP technology affect farmers’ decisions to adopt GAP technology? We also developed an ‘indirect’ approach to reduce the potential sample selection bias for small samples. For the dry-season subsample, GAP farms were more technically efficient when compared with non-GAP farms. These dry-season non-GAP farms may not adopt the GAP method because they have limited access to GAP technology. For the rainy-season subsample, on average, GAP farms were more efficient than non-GAP farms at the 5% level. Access to the GAP technology is not a possible reason for non-GAP rainy season farms to not adopt the GAP technology. To enable sustainable development, government agencies and nongovernmental organizations (NGOs) must develop and implement appropriate educational and training workshops to promote and assist GAP technology adoption for chili farms in Thailand.

scholarly journals Application of Sentinel-1 and-2 Images in Measuring the Deformation of Kuh-e-Namak (Dashti) Namakier, Iran

2021 ◽  
Vol 13 (4) ◽  
pp. 785
Author(s):  
Sen Zhang ◽  
Qigang Jiang ◽  
Chao Shi ◽  
Xitong Xu ◽  
Yundi Gong ◽  
...  
Keyword(s):  
Synthetic Aperture Radar ◽  
Rock Salt ◽  
Rainy Season ◽  
Surface Deformation ◽  
Meteorological Data ◽  
Dry Season ◽  
Synthetic Aperture ◽  
Advantages And Disadvantages ◽  
Sbas Insar ◽  
Aperture Radar

Kuh-e-Namak (Dashti) namakier is one of the most active salt diapirs along the Zagros fold–thrust belt in Iran. Its surface deformation should be measured to estimate its long-term kinematics. Ten Sentinel-2 optical images acquired between October 2016 and December 2019 were processed by using Co-Registration of Optically Sensed Images and Correlation (COSI-Corr) method. Forty-seven Sentinel-1 ascending Synthetic Aperture Radar (SAR) images acquired between April 2017 and December 2019 were processed by using Small Baseline Subset Synthetic Aperture Radar Interferometry (SBAS-InSAR) method. The deformation of Kuh-e-Namak (Dashti) namakier was measured using both methods. Then, meteorological data were utilized to explore the relationship between the kinematics of the namakier and weather conditions and differences in macrodeformation behavior of various rock salt types. The advantages and disadvantages of COSI-Corr and SBAS-InSAR methods in measuring the deformation of the namakier were compared. The results show that: (1) The flank subsides in the dry season and uplifts in the rainy season, whereas the dome subsides in the rainy season and uplifts in the dry season. Under extreme rainfall conditions, the namakier experiences permanent plastic deformation. (2) The “dirty” rock salt of the namakier is more prone to flow than the “clean” rock salt in terms of macrodeformation behavior. (3) In the exploration of the kinematics of the namakier via the two methods, COSI-Corr is superior to SBAS-InSAR on a spatial scale, but the latter is superior to the former on a time scale.

Sign in / Sign up

Export Citation Format

Share Document