• Title/Summary/Keyword: Ecological distribution

Search Result 1,413, Processing Time 0.025 seconds

Spatial Analysis of Colorectal Cancer in Iran

  • Pakzad, Reza;Moudi, Asieh;Pournamdar, Zahra;Pakzad, Iraj;Mohammadian-Hafshejani, Abdollah;Momenimovahed, Zohre;Salehiniya, Hamid;Towhidi, Farhad;Makhsosi, Behnam Reza
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.17 no.sup3
    • /
    • pp.53-57
    • /
    • 2016
  • Colorectal cancer is one of the most common cancers. Due to demographic changes, it is predicted that the incidence of this cancer will increase. Variations of its incidence rate among geographical areas are due to various contributing factors. Since there have been a lack of studies on this topic in our country, the present assessment of spatial patterns of colorectal cancer incidence in Iran was performed. In this ecological study, the new cases of colon cancer were extracted from Cancer Registry Center report of the Health Deputy of Iran in 2009. The reported incidences of the disease were standardized on the basis of the World Health Organization population and the direct method. Then the data were inserted into the GIS software, and finally, using the analysis of hot spots (Getis-Ord Gi) high-risk areas were drawn. Provinces that are higher or lower than the national average (1.9 SD) were considered hot spots or cold spots, significant at the level of 0.05. A total of 6,210 cases of colorectal cancer were registered in Iran in 2009, of which 3,727 were in men and 2,783 in women (age-standardized rates of 11.3 and 10.9 per 100,000 population, respectively). The results showed that in central and northern Iran including Isfahan, Qom, Tehran, Qazvin and Mazandaran significant hot spots in men were present (p <0.05). In women also we have high incidence in northern and central states: Mazandaran province (p<0.01) and the province of Tehran (p<0.05) had higher incidences than the national average and were apparent as significant hot spots. Analysis of the spatial distribution of colorectal cancer showed significant differences between different areas pointing to the necessity for further epidemiological studies into the etiology and early detection.

Developing an Endangered Species Habitat Management System based on Location Information (위치정보 기반 멸종위기종 서식지 관리시스템 개발)

  • Kim, Sun-Jib;Kim, Sang-hyup
    • Journal of Internet of Things and Convergence
    • /
    • v.6 no.3
    • /
    • pp.67-73
    • /
    • 2020
  • The research status of endangered amphibians in Korea was mainly studied the life-cycle and distribution status of species from the 1980s to the early 2000s. Although a relatively diverse range of studies have been conducted on mackerels, studies on habitat prediction, analysis, change and management are insufficient. WEB, which provides biota information using location information in Korea, is a site operated by the National Bio Resource Center under the Ministry of Environment, but there is no information on endangered species and general species information has also been found to be very scantily. For this research, we secured a database of location information of Narrow-mouth frog, an endangered species, by combining literature and field research, and established a system by applying new technologies and open-based platform technologies that can be easily accessed by non-technical personnel of IT among IT technologies. The system was divided into administrator functions and user functions to prevent indiscriminate sharing of information through authentication procedures through user membership of users. The established system was authorized to show the distance between the current location and the location of the Narrow-mouth frog. Considering the ecological characteristics of the Narrow-mouth frog, which is an endangered species, a radius of 500m was marked to determine the habitat range. The system is expected to be applied to the legal system to change existing protected areas, etc. and to select new ones. It is estimated that practical reduction measures can be derived by utilizing the development plan for reviewing the natural environment. In addition, the deployed system has the advantage of being able to apply to a wide variety of endangered species by modifying the information entered.

An Analysis of Vegetation-Environment Relationship in Mt. ManDeok by TWINSPAN (Two-Way Indicator Species Analysis) and DCCA (Detrended Canonical Correspondence Analysis) Ordination (TWINSPAN과 DCCA에 의한 만덕산(萬德山)의 삼림군낙(森林群落)과 환경(環境)의 상관(相關) 분석(分析)에 관(關)한 연구(硏究))

  • Chung, Jin Chul;Jeon, Kyung Soo;Jang, Kyu Kwan;Choi, Jung Ho
    • Journal of Korean Society of Forest Science
    • /
    • v.83 no.2
    • /
    • pp.262-269
    • /
    • 1994
  • In order to determine ecological niches of forests in Mt. ManDeok, the studies were analyzed on the methods of TWINSPAN and DCCA ordination. The results are summarized as follows ; Four groups were determined by TWINSPAN : Styrax japonica. Quercus variabilis-Quercus mongolica, Carpinus laxiflora and Fraxinus mandshurica-Cornus controversa communities. In the relations of community structures and environmental factors, Styrax japonica community were distributed in the rich site of magnesium and organic matter, Quercus variabilis-Quercus mongolica community in the low potassium, Carpinus laxiflora community in the low available phosphorus, and the factors in influencing community distribution were elevation. The importance value of Quercus variabilis recorded the highest in all the quadrats sampled and the next values then came those Cornus controversa. Quercus variabilis, Lindera erythrocarpa. Quercus mongolica, Fraxinus mandshurica. Cornus controversa, Symplocos chinensis for pilosa, Acer mono, Carpinus laxiflora, and Styrax japonica in the orders. The species diversities of major dominant species recorded the highest value in the communities of Quercus variabilis-Quercus mongolica but they lowest value in the communities of Fraxinus mandshurica-Cornus controversa.

  • PDF

How are the Spatio-Temporal Distribution Patterns of Benthic Macrofaunal Communities Affected by the Construction of Shihwa Dike in the West Coast of Korea? (시화방조제의 건설은 저서동물군집의 시${\cdot}$공간 분포에 어떠한 영향을 미쳤는가?)

  • HONG Jae-Sang;JUNG Rae-Hong;SEO In-Soo;YOON Kon-Tak;CHOI Byong-Mee;YOO Jae-Won
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.30 no.5
    • /
    • pp.882-895
    • /
    • 1997
  • Changes in the benthic communities have been studied to investigate the environmental effects before and after the construction of Shihwa Dike in the West coast of Korea. It is suggested that sequential changes in macrofaunal assemblages progressed in two sucressional directions. In the Shihwa lake under the influence of organic enrichment. First, the appearance of 'azoic tone' or 'grossly polluted zone' developed in the area of less than 6 m in depth resulted from the severe dissolved oxygen depletion due to the eutrophication from the increased organic loading. Second, the 'polluted zone' characterized by the proliferation of the opportunistic species in organically enriched area, was found in the vicinity of the industrial discharges and nearby fluvial inputs. This benthic community succession in the Shihwa lake seemed to be caused by the various ecological events such as an eutrophication in this organically enriched environment after construction of the dike and other physico-chemical parameters like salinity and dissolved oxygen in the bottom water, which may be influenced by the irregular surface water discharge and dilution by outer seawater inflow through the water gate of the dike. On the other hand, the benthic communities in the outside of the dike showed that the species richness was more than doubled and the abundance increased almost seven times more than that before the dike construction. This may be a typical characteristics of the initial phase in benthic eutrophication, suggesting that an increased organic input area may have been reponsible for this faunal change in the study area.

  • PDF

Marine Environmental Assessment based on the Benthic Macroinfaunal Compositions in the Coastal Area of Inchon, Korea (인천연안역 저서동물의 종조성을 이용한 환경평가)

  • LEE Jae-Hac;KOH Byoung-Seol;PARK Heung-Sik
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.30 no.5
    • /
    • pp.771-781
    • /
    • 1997
  • In order to select an effective and appropriate evaluation method for the marine environmental protection and management, it is necessary to evaluate the present status of environmental conditions and to monitor and regulate the harzadous waste continuously. Among the evaluation methods that use benthic fauna, some graphical methods and biological index methods such as species abundance-biomass (SAB), Rank-frequency diagram (RFD), Abundance-Biomass comparison (ABC), log-normal distribution (LND), and Benthic Pollution Index (BPI) modified by Infaunal Trophic Index were used for the assessments of marine environment in the Inchon coastal area. Even though the graphic methods are convenient for easy glimpse of general trend of environmental condition but because they require sufficient ecological data, those methods do not fit for analysis or comparison of regional and detailed environmental condition. On the other hand, when BPI was applied, it was able to compare the spatial benthic conditions. Through considering the functional aspects of benthic fauna which can not be obtained in the cluster analysis, BPI was made it possible to measure or trace down the source of pollution. In the case of the environmental assessment result analyzed in Inchon coastal area, the north eastern part of Yongjongdo was more influenced by the pollution than the outer area of Inchon. The research indicates that especially Inchon harbor has been greatly affected.

  • PDF

AN ECOLOGICAL STUDY OF TUNA LONG LINE CATCH DISTRIBUTION OBTAINED BY EXPERIMENTAL FISHING OPERATIONS (다랑어연승 실험조업의 조획물조성에 의한 어업생태학적연구)

  • PARK Sing Won
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.2 no.2
    • /
    • pp.161-172
    • /
    • 1969
  • Ten experimental tuna long line fishing operations were performed with the long lines A and B, in combination casting orders of BA and AB. The long line B differs from A in its additional main line length per basket and its greater depth of submersion (Table 1). The BA casting order results in an AB hauling order, so that the long line B is casted at an earlier time of a day and fishes for a longer period than A line (fig. 2). The number of fish caught was divided into subclasses in order to be subjected to $x^2-tests$ (Table 2). The first series of $x^2-tests$ were calculated using the hooking rates of two subclasses with other factors pooled (Table 3). The second series of $x^2-tests$ were calculated to obtain the interactions between two subclasses when other factors differed (Table 4). Attention was paid to the extremely small interactions as well as to the large interactions in order to find out whether a factor functions in the same way or in a contradictory way when the other factors involved differ. The test result is summarized in Table 5. The relationship between the hook casting time (relative to the sunrise time) and the hooking rates reveals the feeding behavior of particular species (fig. 3) A high hooking rate for yellowfin tuna shown in the period from one hour before sunrise to the moment of sunrise suggests that they feed actively in that period. Their poor hooking rate on earlier casted hooks suggests that they do not feed well under conditions of darkness and that they feed best while the hooks are sinking. Furthermore it is likely that yellowfin tuna maintain a shallow depth in the daytime, for the $x^2$ interaction between the line casting order BA and AB shows their persistant preferance of the long line A regardless of line casting order. Bigeye tuna show their feeding behavior under conditions of darkness, and show a preference for the sea's deeper layer. Alepisaurus borealis (Gill) show their feeding behavior under conditions of darkness more significantly than the bigeye tuna and their preferance for deep layers is also more significant. Marlins (mainly Makaria mazara) show a feeding behavior which is similar to the yellowfin tuna. The author emphasizes that certain variations of the hooking rates in relation to the line easting time were caused by an inadequate fishing depth as well as by the fish preference for a particular feeding time. When the part of the line casted in pre-dawn hours and hauled in the pre-sunset hours show a significantly lower hooking rate than other parts of the line, then it is concluded that tile hooks settled in a sea layer too deep for feeding.

  • PDF

An Ecological Analysis of Lichens Distributed in Rocks of Coast and Field in U-do by Molecular Technique (분자생물학적 기법에 의한 우도해안과 노지암석에 분포하는 지의류의 생태학적 분석)

  • Gang, Hyeong-Il;Yun, Byeong-Jun;Kim, Seong-Hyeon;Sin, Deok-Ja;Kim, Hyeon-U;Heo, Jae-Seon;Gang, Ui-Seong;O, Gye-Heon;Go, Yeong-Jin
    • Microbiology and Biotechnology Letters
    • /
    • v.32 no.4
    • /
    • pp.334-340
    • /
    • 2004
  • This study was initially performed to obtain fundamental data on lichen distribution depending on environmental condiLichens distributed on coastal rocks atleast 20 m far away from the coast were also investigated. Analyof morphological characteristics and rDNA ITS clones revealed that lichens containing 9 families and 15 genera were distributed in coastal rocks of V-do, while lichens containing 10 families and 14 genera were in field rocks, demonstrating little difference of diversity between both sites. Foliose lichens such as PhaeophysPhyscia, Pyxine belonging to the family Physciaceae were representatives distributed in coastal rocks of V-do, along with Xanthoparmelia belonging to Parmeliaceae, fruticose lichens such as Ramalina to Ramaliand crustose lichen Lecanora to Lecanoraceae. In contrast, foliose lichen Cladonia belonging to the family Cladoniaceae, fruitcose lichen Stereocaulon to Streocaulaceae, and crustose lichen Porpidia to Porpidwere found only on the surface of field rocks. Crustose lichens containing genera Caloplaca, CanDirinaria, Graphis, Rhizocarpon, and Pertusaria were rarely distributed in coastal rocks, and most of them were also found in field rocks.

Molluscan Death Assemblages and Their Ecological Implications on a Tidal Flat, Inchon, Korea (인천연안 간석지산 연체동물 유해집단(遺骸集團)의 구조와 생태학적 의미)

  • Hong, Jae-Sang;Park, Heung-Sik
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
    • /
    • v.3 no.2
    • /
    • pp.94-102
    • /
    • 1998
  • Temporal changes, density, calcimass, mode of occurrence, size-frequency histogram and survivorship curves were studied for the molluscan death assemblages on a macrotidal flat, Inchon, Korea. The living and death assemblages were compared on the basis of the taxonomic compositions and their numerical abundances. A total of 28 species (16 taxa in gastropods and 12 in bivalves) were identified. Most of the dead shells were the species inhabiting that intertidal mud flat. Species diversity was higher in gastropods than in bivalves. Seasonal variation of the calcimass was influenced by the mactrid bivalve, Mactra veneriformis. Shell-boring naticid gastropods preferred selecting the umbo areas of various valves. Size-frequency distribution and size-specific survivorship curves were analyzed for the dominant species. Survivorship curve of the tellinid bivalve, Morella rutila was convex-up in shape, which is congruent with the expected equilibrium condition but indicates higher mortality in winter. Whereas the survivorship curves of Mactra veneriformis and Reticunassa festiva were semi convex-up with dual modes, suggesting a disequilibrium due to the changes in recruitment and seasonal mortality. This study suggests that the dead shell assemblages may be useful in getting population information like live molluscan assemblages, if solved for several problems related to taphonomic processes.

  • PDF

Tracing Source and Concentration of Riverine Organic Carbon Transporting from Tamjin River to Gangjin Bay, Korea (탐진강-강진만의 댐하류 열린하구 시스템에서 유기탄소의 조성 및 기원 변화 연구)

  • Park, Hyung-Geun;Kang, Dong-Won;Shin, Kyung-Hoon;Ock, Giyoung
    • Korean Journal of Ecology and Environment
    • /
    • v.50 no.4
    • /
    • pp.422-431
    • /
    • 2017
  • The biogeochemical information of riverine organic matter gives a detailed and integrated recording of natural and anthropogenic activity within a watershed. To investigate the changes in quality and quantity of organic carbon transporting from mountain to ocean via river channels, we estimated the concentrations of dissolved (DOC) and particulate organic carbon (POC), and then traced the source origin of POC using stable carbon isotopes ratio before and after summer rainfalls in the Tamjin River and Ganjin Bay, Korea. Along the small watershed, a total of 13 sites including headwaters, dam reservoir, river and estuary were established for the study. We found some interesting findings in the aspect of distribution of DOC/POC concentration changing their origin sources dynamically flowing downstream. In particular, the river channel transport downstream mainly DOC to river mouth, although upper dam reservoir increased POC concentration by phytoplankton production in summer. Whereas, in the river mouth and estuary, POC was dominated not only by local supply from nearby reed saltmarsh, but also by marine phytoplankton production, respectively. The findings can contribute to increasing the understanding of riverine organic carbon transport in upper large dam and lower open estuary system.

Temporal and Spatial Pattern of Ambient Nitrogen Dioxide Concentration in Forest and Urban Areas, Korea (우리나라 산림과 도시지역의 이산화질소 농도의 시·공간적 패턴)

  • Lee, Seung-Woo;Lee, Choong-Hwa
    • Korean Journal of Agricultural and Forest Meteorology
    • /
    • v.13 no.4
    • /
    • pp.165-170
    • /
    • 2011
  • The ambient concentrations of nitrogen dioxide ($NO_2$) at 65 forest areas were measured every month using passive diffusive samplers from 2002 to 2009 and were compared to those at urban areas in order to investigate the characteristics of temporal and spatial distributions of $NO_2$ from the forest and urban areas. The annually averaged concentrations of $NO_2$ gradually decreased for both areas. The average concentration of $NO_2$ in the forest areas was 8.0 ppb, which was lower than that in the urban areas (i.e., 19.4 ppb) and the ecological standard level of the European Union (i.e., 14.6 ppb). The monthly average of $NO_2$ concentration depicted seasonal variations particularly in the urban areas, showing higher concentration in winter and lower concentration in summer. Strong locality of $NO_2$ concentration distribution illustrates that the locations near the metropolitan areas (e.g., Gyeonggi and Chungnam provinces) had the highest concentration during the measurement period. A significant positive correlation between $NO_x$ emissions and $NO_2$ concentration was observed, suggesting that the magnitude and proximity to sources of atmospheric nitrogen oxides would be important controlling factors.