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1.
China Tropical Medicine ; (12): 10-2023.
Article in Chinese | WPRIM | ID: wpr-974101

ABSTRACT

@#Abstract: Objective To predict the potential distribution of talaromycosis marneffei (TSM) and analyze its driving factors, so as to provide evidence for the surveillance and prevention of this disease. Methods The data of all laboratory-confirmed, non-duplicating TSM published in the English and Chinese literature from the first case in January 1964 to December 2018 was collected. A Maxent ecology model using environmental variables, Rhizomys distribution and HIV/AIDS epidemic was developed to forecast ecological niche of TSM worldwide, as well as identify the driving factors. Results A total of 705 articles (477 in Chinese and 228 in English) were obtained during the study period. After excluding imported cases, a total of 100 foci information were included in the model. The area under the receiver operating characteristic (ROC) curve (AUC) of the model was 0.997 for the training set and 0.991 for the test set. Maxent model revealed that Rhizomys distribution, mean temperature of warmest quarter, precipitation of wettest month, HIV/AIDS epidemic and mean temperature of driest quarter were the top 5 important variables affecting TSM distribution. In addition to identifying traditional TSM endemic areas (South of the Yangtze River in China, Southeast Asian, North and Northeast India), other potential endemic areas were also identified, including parts of the North of the Yangtze River, Central America, West Coast of Africa, East Coast of South America, the Korean Peninsula and Japan. Conclusion Our finding has discovered hidden high-risk areas and provided insights about driving factors of TSM distribution, which will help inform surveillance strategies and improve the effectiveness of public health interventions against TM infections.

2.
Rev. biol. trop ; 70(1)dic. 2022.
Article in Spanish | LILACS, SaludCR | ID: biblio-1387721

ABSTRACT

Resumen Introducción: Spiraxidae es la familia de gasterópodos terrestres más diversa de México con una distribución principalmente neotropical. Sin embargo, la influencia de las condiciones ambientales de esta región en su distribución aún es poco conocida. Objetivo: Determinar las afinidades zoogeográficas y la influencia de factores ambientales en la distribución de Spiraxidae en México. Métodos: Compilamos registros de distribución de museos y usamos modelos para establecer áreas con composición de especies, concentración de especies, afinidades y relaciones con variables ambientales similares. Resultados: Encontramos 231 especies y subespecies, 96 en el estado de Veracruz y 74 en la Sierra Madre Oriental. La principal afinidad zoogeográfica fue neotropical. El bosque mesófilo de montaña tuvo la mayor cantidad de especies y subespecies (93). Tres de los grupos zonales tienen una composición particular de especies y el 67 % de las especies son especialistas de hábitat. La presencia de especies sigue un gradiente ambiental, con la cubierta de árboles de hoja perenne de hoja ancha y la precipitación media anual como variables determinantes. Las especies del norte tuvieron mayor tolerancia a la aridez y menor cobertura de hojas. Conclusiones: Spiraxidae tiene su mayor diversidad en los estados del Sur de México; sin embargo, la zona nororiental tiene más registros de especies. Estos caracoles se encuentran principalmente en bosques mesófilos de montaña y bosques tropicales siempre verdes. Las especies del norte de México tuvieron una mayor tolerancia a los sitios con poca lluvia y menos cobertura de árboles de hoja perenne de hoja ancha que las especies del sur.


Abstract Introduction: Spiraxidae is the most diverse family of terrestrial gastropods in Mexico with a mainly neotropical distribution. However, the influence of environmental conditions in this region on its distribution is still poorly known. Objective: To determine zoogeographic affinities and the influence of environmental factors on the distribution of Spiraxidae in Mexico. Methods: We compiled museum distribution records and used models to establish areas with similar species composition, species concentration, affinities and relationship with environmental variables. Results: We found 231 species and subspecies, 96 in Veracruz state and 74 in Sierra Madre Oriental. The main zoogeographic affinity was neotropical. Mountain mesophyll forest had the most species and subspecies (93). Three of zone groups have a particular species composition and 67 % of the species are habitat specialists. Species presence follows an environmental gradient, with broadleaf evergreen tree cover and average annual precipitation as determining variables. Northern species had greater tolerance to aridity and reduced leaf cover. Conclusions: Spiraxidae has its greatest diversity in the Southern states of Mexico; however, the Northeastern zone has more species records. These snails mostly occur in mesophyll mountain forest and tropical evergreen forest. Species from Northern Mexico had greater tolerance to sites with low rainfall and less broadleaf evergreen tree cover than Southern species.


Subject(s)
Animals , Snails/classification , Animal Distribution , Mexico
3.
China Journal of Chinese Materia Medica ; (24): 1196-1204, 2022.
Article in Chinese | WPRIM | ID: wpr-928043

ABSTRACT

Chuanxiong Rhizoma is a traditional Chinese medicinal material mainly produced in Sichuan and Chongqing of China. In recent years, the cadmium content in Chuanxiong Rhizoma produced in most of the genuine producing areas has exceeded the standard, which makes Chuanxiong Rhizoma difficult to be exported. To solve the problem of excessive cadmium content in soil, this study employed the MaxEnt model to simulate the potential geographic distribution of Ligusticum chuanxiong and evaluate important environmental factors, and re-plan its ecologically suitable areas based on the mineral distribution characteristics and soil cadmium pollution status. The results showed that the places suitable for L. chuanxiong growing covered an area of 335 523.69 km~2, mainly in central and eastern Sichuan, southern Shaanxi and most parts of Chongqing. Among them, the highly suitable areas of L. chuanxiong were mainly concentrated in Chengdu, Ya'an, Deyang, and Mianyang. Solar radiation, annual precipitation, and annual range of temperature were evaluated as important variables affecting the distribution of L. chuanxiong, with the contribution rates of 62.3%, 13.3%, and 6.8%, respectively. In addition, Qionglai county, Chongqing county, Mianyang city(Youxian district and Fucheng district), Qingchuan county, and Xinjin county were classified into the first-class ecologically suitable zone, covering a total area of 2 768.87 km~2. The se-cond-class ecologically suitable zone was even wider, involving such counties as Tongjiang county, Renshou county, Jianyang county, and Nanjiang county, and the total area reached 43 616.92 km~2. The re-planning of the ecologically suitable areas for L. chuanxiong has provided strong data support for the cultivation and resource development of L. chuanxiong and also new ideas for solving the problem of excessive cadmium content in L. chuanxiong.


Subject(s)
Cadmium/toxicity , Environmental Pollution , Ligusticum , Rhizome , Soil
4.
Tropical Biomedicine ; : 373-383, 2022.
Article in English | WPRIM | ID: wpr-959337

ABSTRACT

@#Ae. aegypti is a dengue virus vector and a public health threat in Indonesia. Furthermore, the Dengue Haemoragic Fever (DHF) has spread to all cities in the country, including Bandar Lampung. A species distribution model, Maximum Entropy (MaxEnt), was used to predict the geographic distribution of this vector in three dengue-endemic areas, namely Sukarame, Kemiling, and Tanjung Seneng. Previously, surveillance was conducted to determine the presence of Ae. aegypti. Therefore, this study suggested that environmental variables such as rainfall, temperature, land cover, and population density have influenced the widespread of Ae. aegypti and facilitate its proliferation in the study areas. The influence of the environmental variables was analyzed using a response curve. The model performance was measured by percent contribution, the importance of permutations, and the jackknife test. This study’s evaluation indicates that the certainty models for the presence of Ae. aegypti in Sukarame, Kemiling, and Tanjung Seneng were developed extremely well, with respective values of 0.989, 0.993, and 0.969. The results showed that Ae. aegypti is widespread in the three endemic areas. The high population density and land conversion into settlements are influential environmental variables essential in determining the distribution of the vector in three areas of Bandar Lampung. Climatic factors such as rainfall and temperature are supporting aspects in maintaining the habitat of Ae. aegypti in the area. Mapping areas at risk of this dengue vector can aid in planning disease management strategies and identifying priority locations for entomological surveys to control epidemics.

5.
Rev. peru. biol. (Impr.) ; 28(2): e18187, abr.-jun 2021. tab, graf
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1280515

ABSTRACT

Resumen El modelado de escenarios de cambios climáticos utilizando sistemas de información geográfica para estimar la resiliencia de la cobertura vegetal es una herramienta útil para proyectar impactos futuros e implementar estrategias de conservación o manejo. En el presente trabajo asociamos espacialmente la biodiversidad de la cobertura vegetal del Suroeste de México con su capacidad para adaptarse a los efectos del cambio climático. Para analizar esta asociación se estimaron índices de riqueza y diversidad de especies, y su relación con escenarios de clima futuro. Se utilizaron los registros geográficos del Inventario Nacional Forestal y de Suelos para ocho comunidades vegetales (arbórea, arbustiva, herbácea, palma, cactus, bejucos, helechos y xerófita) distribuidas entre Guerrero, Oaxaca y Chiapas. La proyección climática fue al 2050, con modelos de circulación global A2 (promedio CCCMA, HADCM3 y CSIRO), 19 variables bioclimáticas y una resolución de 2.5 minutos. Los escenarios de cambio climático se modelaron con el algoritmo MaxEnt y la riqueza de especies, índice de diversidad y regresiones espaciales con el software Diva-GIS v7.5. Los modelos de regresión espacial estimaron que a mayor riqueza y diversidad de especies mayor seria la resiliencia que mostraría el ecosistema. Las comunidades vegetales cactus, palma y xerófita mostraron mayor vulnerabilidad al cambio climático. Las variaciones en la estacionalidad de la temperatura resultó ser el factor que condicionaría su distribución futura. Por lo que, las estrategias de conservación o manejo deberían considerar a la diversidad como un agente del ecosistema que amortiguaría a los efectos negativos del clima futuro.


Abstract The scenarios modeling of climate changes using geographic information systems to estimate the vegetation cover resilience is a useful tool to project future impacts and implement conservation or management strategies. We associate spatially the biodiversity of the vegetation cover of Southwest Mexico with its ability to adapt to the effects of climate change. We analysis this association estimating species richness and diversity indices, and its relationship with scenarios of future climate. Geographical records of the National Forest and Soil Inventory were obtained for eight plant communities (arboreal, shrubby, herbaceous, palm, cactus, vines, ferns, and xerophyte) distributed in Guerrero, Oaxaca, and Chiapas. The climatic projection was to 2050, with global circulation A2 models (CCCMA, HADCM3 and CSIRO average), 19 bioclimatic variables and a resolution of 2.5 minutes. Climate change scenarios were modelled with the MaxEnt algorithm and species richness, diversity index, and spatial regressions with Diva-GIS v7.5 software. The spatial regression models estimated that higher richness and species diversity, the greater resilience that the ecosystem would show. The cactus, palm, and xerophytic plant communities presented greater vulnerability to climate change. Variations in temperature seasonality turned out to be the factor that would condition its future distribution. Therefore, in conservation or management strategies, diversity should be considered as an agent of the ecosystem that cushions the negative effects of future climate.

6.
Rev. biol. trop ; 69(1)2021.
Article in English | LILACS, SaludCR | ID: biblio-1507819

ABSTRACT

Introduction: Migration of people from rural environments to cities has accelerated urbanization and modified the landscape as well as the ecological processes and communities in these areas. The Costa Rican endemic Cabanis´s Ground-Sparrow (Melozone cabanisi) is a species of limited distribution restricted to the "Gran Area Metropolitana", which is the biggest urban settlement of the country. This area has experimented and still experiment an ongoing fragmentation and loss of habitat used by this species (coffee plantations, shrubs, and thickets). Objective: To determine the effects of urbanization on habitat abundance and spatial pattern for the occurrence of Melozone cabanisi. Methods: We modeled the area of potentially suitable habitat for this species in Costa Rica using occurrence and bioclimatic data. Then, we estimated the actual suitable habitat using land cover type layers. Finally, we analyzed the connectivity among the actual suitable habitat patches using single-patch and multi-patch approaches. Results: From the area of potentially suitable habitat estimated by the bioclimatic model, 74 % were urban areas that are unsuitable for Melozone cabanisi. The largest suitable patches within urban areas were coffee plantations; which also were crucial for maintaining connectivity between habitat patches along the species' range. Conclusions: To preserve and protect the Melozone cabanisi, these areas must be taken into consideration by decision-makers in the present and future management plans. We recommend avoiding change shrubs and thickets to urban cover to preserve the occurrence of Melozone cabanisi, and implement a program for the payment of environmental services to landholders, supported by the local governments, to protect those habitats in urban contexts.


Introducción: La migración desde ambientes rurales hacia las ciudades ha incrementado la urbanización. Esto ha modificado el paisaje, así como los procesos ecológicos y comunidades dentro de estas áreas. El Cuatro-ojos de Jupa-roja (Melozone cabanisi) es una especie distribuida principalmente al interior del asentamiento urbano más grande de Costa Rica. Hasta el presente esta área sigue experimentando fragmentación y pérdida del hábitat utilizado por esta especie (plantaciones de café, charrales y tacotales). Objetivo: Determinar los efectos de la urbanización sobre la cantidad de hábitat y su distribución espacial, basada en datos de presencia para M. cabanisi. Métodos: Modelamos el hábitat potencialmente adecuado para M. cabanisi utilizando datos bioclimáticos y de presencia. Luego estimamos el hábitat real utilizando el hábitat potencialmente adecuado y las capas de cobertura del suelo. Finalmente analizamos la conectividad entre los parches de hábitat real utilizando un enfoque multi y mono-parche. Resultados: Del área del hábitat potencialmente adecuado estimada por el modelo bioclimático, 74 % fueron áreas urbanas, lo que consideramos es un porcentaje inadecuado para M. cabanisi. Los parches más grandes de hábitat real dentro de las áreas urbanas fueron plantaciones de café, que a su vez fueron cruciales para mantener la conectividad entre los parches a lo largo del rango de distribución de la especie. Conclusiones: Para conservar y proteger a M. cabanisi, los tomadores de decisiones deben tener en cuenta los charrales, tacotales y cafetales dentro de la distribución de las especies en los planes de gestión presentes y futuros, evitando su cambio a coberturas urbanas.


Subject(s)
Animals , Birds/growth & development , Refugium , Cities , Costa Rica
7.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 168-175, 2021.
Article in Chinese | WPRIM | ID: wpr-906407

ABSTRACT

Objective:To analyze the main factors affecting the <italic>Ziziphus jujuba</italic> distribution and expand the understanding of its distribution and the corresponding influencing factors by comparing the distribution sites of <italic>Z. jujuba</italic> predicted by models with those recorded in the literature. Method:More than 200 distribution sites of <italic>Z. jujuba</italic> accompanied by 55 environmental factors were obtained from literature and specimen review. The environmental factors that affect the distribution of <italic>Z. jujuba</italic> were explored by maximum entropy (MaxEnt) model, and the potential distribution areas of <italic>Z. jujuba</italic> in China were analyzed by ArcGIS, followed by the verification of the main environmental factors using receiver-operating characteristic (ROC) curve and Jackknife method. Result:The area under the curve (AUC) values for the test data and training data were both greater than 0.9, which perfectly satisfied the standard, indicating that the research results were accurate and reliable. Conclusion:The annual average temperature, the average temperature in May, the average temperature in the warmest season, vegetation type, soil type, average temperature in June, average temperature in September, and average temperature in August are proved to be the main environmental factors affecting the distribution of <italic>Z. jujuba</italic>, which can be found almost all over China, except for Heilongjiang and Tibet. <italic>Z. jujuba</italic> is most suitable to be planted in southeastern Sichuan, Chongqing, southern Gansu, Ningxia, most areas of central Shaanxi, eastern and southwestern Shanxi, Henan, eastern and northern Hubei, northern and eastern Anhui, Shandong, Hebei, Beijing, Tianjin, western Liaoning, and Zhejiang. As revealed by literature review, the most suitable growing areas of <italic>Z. jujuba</italic> are southeastern Sichuan, central Shaanxi, southwestern Shanxi, western and northern Henan, Shandong, and southwestern and eastern Hebei.

8.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 172-180, 2021.
Article in Chinese | WPRIM | ID: wpr-905878

ABSTRACT

Objective:To explore the potential suitable distribution area and the high-quality distribution area of <italic>Sabia parviflora</italic>. Method:Combined with the distribution information and environmental factors,the maximum entropy (MaxEnt) model and ArcGIS software were used to predict the potential suitable distribution area of <italic>S. parviflora</italic>. Based on the correlation between environmental factors and total saponins,total flavonoids,quercetin-3-<italic>O</italic>-gentiobioside,camellianoside,tsubakioside A,kaempferol-3-<italic>O</italic>-rutinoside and isobariclisin-3-<italic>O</italic>-rutinoside,the quality regionalization was conducted by using spatial interpolation method and fuzzy superposition function in ArcGIS software. Result:<italic>S. parviflora</italic> is mainly distributed in Yunnan,Guizhou,Guangxi province in China. The medium and high suitable areas accounts for about 2.88% of the national area. The precipitation in October and November,the precipitation in the warmest and driest seasons,the standard deviation of seasonal changes in temperature and altitude are the main environmental factors that affect the distribution of <italic>S. parviflora</italic>. Slope,precipitation,solar radiation and temperature change had great influence on the accumulation of secondary metabolites. Based on the results of potential suitable distribution and spatial interpolation of each component,the high-quality areas of <italic>S. parviflora</italic> are mainly concentrated in the southwest of Guizhou,with Qinglong,Guanling,Zhenning,Pu'an,Xingren county and other areas as the core. Conclusion:This study provides a scientific guidance for the site selection of artificial planting and the procurement of medicinal materials for <italic>S. parviflora</italic>.

9.
Chinese Journal of Experimental Traditional Medical Formulae ; (24): 122-129, 2021.
Article in Chinese | WPRIM | ID: wpr-905841

ABSTRACT

Objective:Polygalae Radix is mainly produced in Northeast,North,Northwest and Central China and Sichuan province. There are obvious differences in quality of <italic>Polygala tenuifolia</italic> from different areas. <italic>P. tenuifolia</italic> cultivation areas are relatively concentrated. Currently,there are only a few studies about the suitability zoning of <italic>P. tenuifolia</italic> nationwide,in order to determine the suitable zoning of <italic>P. tenuifolia</italic> in China. This paper made a habitat suitability evaluation of <italic>P. tenuifolia</italic> nationwide based on analysis of ecological factors in distribution areas of sampling points. Method:MaxEnt model was used to select ecological factors that affected the distribution of <italic>P. tenuifolia</italic> and construct an evaluation model. ArcGIS software was used to evaluate the suitability of different habitats of<italic> P. tenuifolia</italic>. The suitable areas were classified into high,medium,low suitability areas and unsuitable area of <italic>P. tenuifolia</italic> nationwide. Result:The evaluation model was highly accurate,and concluded that <italic>P. tenuifolia'</italic>s suitability distribution area in China was 3.21×10<sup>6</sup> km<sup>2</sup>,including 0.52×10<sup>6</sup> km<sup>2</sup> of high suitability area,0.96×10<sup>6</sup> km<sup>2</sup> of medium suitability area and 1.73×10<sup>6</sup> km<sup>2</sup> of low suitability area. High suitability areas were mainly distributed in Shanxi province,Hebei province,Shandong province,Shaanxi province,Liaoning province and Henan province. The main ecological factors affecting the distribution of <italic>P. tenuifolia</italic> were annual average temperature change range,mean temperature of driest quarter,precipitation of wettest quarter,altitude,slope and topsoil (0-30 cm) calcium carbonate. Conclusion:The results of the study are consistent with the records in relevant literatures,and can provide a theoretical basis for protection and cultivation of Chinese medicine resource <italic>P. tenuifolia</italic>.

10.
Chinese Traditional and Herbal Drugs ; (24): 3304-3307, 2020.
Article in Chinese | WPRIM | ID: wpr-846370

ABSTRACT

Objective: To study the ecological suitability of Angelica sinensis growing in Gansu Province and guide the rational cultivation. Methods: Through visiting and field investigation, 1 545 batches of Chinese angelica samples were collected from the county areas in Gansu Province. The information about the longitude, latitude, altitude of each sampling point was collected by using the GPS, combining with national environmental factor data, and using Maxent model and spatial analysis function of ArcGIS software. Results: The areas with high suitability of A. sinensis distribution are in the southeast of Gansu Province. The main ecological factors affecting the suitability distribution of A. sinensis were altitude, rainfall in March, May and December, wettest month precipitation, soil pH and other ecological factors. Conclusion: The research findings are basically consistent with the living habits of A. sinensis that cultivated in high-cold mountain areas and plateau flat pasture areas with a cool climate, moderate soil, moisture, slightly acidic to neutral fertile and loose brown sandy loam soil. This result can provide scientific basis for the reasonable distribution of A. sinensis cultivation area in Gansu Province.

11.
Rev. biol. trop ; 66(3): 1272-1281, jul.-sep. 2018. graf
Article in English | LILACS, SaludCR | ID: biblio-977383

ABSTRACT

Abstract Whereas more than 10 % of global amphibian richness is known to occur in Colombia, almost 16 % of these species are currently classified as Data Deficient according to the IUCN. These estimates suggest that the available data for a large portion of amphibians occurring in Colombia is insufficient to assess extinction risk. Here we aim to (1) review the available information on the distribution of the Colombian Data Deficient (DD hereafter) amphibians, (2) analyze their geographic distribution, and (3) evaluate the relationship between anthropogenic impact and their current conservation status. For this, we first compiled geographical records for the DD amphibian species using primary sources. Geographical records were obtained mainly from taxonomic descriptions and non-systematic surveys. We then estimated the geographical range and inferred the potential distribution for each species using letsR and MaxEnt, respectively. We quantified the human footprint for each species and tested the relationship between spatial distribution and anthropogenic change across populations. Analyses are here based on 128 of the 129 DD amphibian species that occur in Colombia. We found that most of these species were recently described and have small geographic ranges. A large proportion of these DD amphibians inhabit the Colombian Andes, and their populations have been strongly affected by human activities. Overall, the spatial clustering suggests that many of these species have faced similar environmental and anthropogenic pressures that have contributed to their rareness. We also suggest that the conservation status for several of the analyzed DD amphibians should be changed to account for the threats they face. Rev. Biol. Trop. 66(3): 1272-1281. Epub 2018 September 01.


Resumen A pesar de que más del 10 % de la riqueza global de anfibios se encuentra en Colombia, cerca del 16 % de estas especies es actualmente clasificada con Datos Deficientes según la IUCN. Estas estimaciones sugieren que los datos disponibles para esta gran porción de anfibios que habitan en Colombia, son insuficientes para evaluar su riesgo de extinción. En este documento nosotros (1) revisamos la información disponible sobre la distribución de los anfibios colombianos con Datos Deficientes (ó DD), (2) analizamos su distribución geográfica, e (3) hipotetizamos sobre la relación entre el impacto antropogénico y su estado de conservación. Para esto, compilamos los registros geográficos para las especies de anfibios DD usando referencias primarias. Los registros geográficos fueron obtenidos principalmente a partir de descripciones taxonómicas y búsquedas no sistemáticas. Para estimar la distribución geográfica e inferir la distribución potencial de cada especie usamos letsR y MaxEnt, respectivamente. Cuantificamos la huella humana para cada especie y evaluamos la relación entre la distribución espacial y el cambio antropogénico entre poblaciones. Los análisis fueron basados en 128 de las 129 especies de anfibios que se encuentran en Colombia y actualmente son clasificadas como DD. Encontramos que la mayoría de estas especies fueron descritas recientemente, y presentan una distribución geográfica reducida. Una gran proporción de estas especies de anfibios DD habitan los Andes colombianos, y sus poblaciones han sido fuertemente afectadas por las actividades humanas. Este agrupamiento geográfico sugiere que muchas de estas especies enfrentan similares presiones ambientales y antropogénicas que contribuyen a su rareza. Sugerimos además que el estado de conservación para muchas de las especies de anfibios DD aquí analizados podría ser reevaluado para considerar las amenazas que enfrentan.


Subject(s)
Colombia , Amphibians
12.
Rev. biol. trop ; 66(1): 321-335, Jan.-Mar. 2018. tab, graf
Article in Spanish | LILACS | ID: biblio-897675

ABSTRACT

Resumen Mimosa aculeaticarpa var. aculeaticarpa y M. luisana son endémicas de México y consideradas plantas multipropósito, ya que ofrecen diversos servicios a los ecosistemas y pobladores en donde se establecen. Además, son valoradas por su potencial como restauradoras de ambientes tropicales, por lo que el objetivo de este estudio fue modelar su distribución conocida y potencial. En el año 2014, se obtuvieron registros de dos bases de datos (CONABIO y MEXU); cada resgistro fue validado taxonómica, geográfica y estadísticamente, una vez validados, se obtuvo la distribución conocida y potencial para M. aculeaticarpa var. aculeaticarpa (basada en 99 registros) y M. luisana (basada en 50 registros), utilizando el algoritmo MAXENT. La distribución conocida de ambos taxa se sobreposicionó en las capas de: elevación, clima, suelo, provincias biogeográficas y cuencas hidrológicas. Mimosa aculeaticarpa var. aculeaticarpa presenta amplia distribución en México (16 estados); mientras que M. luisana se encuentra restringida a los estados de Puebla y Oaxaca. M. aculeaticarpa var. aculeaticarpa se establece entre 1 900 y 2 700 msnm y M. luisana entre 500 y 1 760 msnm. Ambas se encuentran en climas áridos y semiáridos; sin embargo, M. aculeaticarpa var. aculeaticarpa también se puede encontrar en climas templados y mésicos. Asimismo, ambos taxa se distribuyen en suelos de tipo regosol calcárico; aunque, M. aculeaticarpa var. aculeaticarpatambién está en regosol éutrico, vertisol crómico y feozem háplico. La distribución de M. aculeaticarpa var. aculeaticarpa abarca ocho provincias biogeográficas y tres cuencas hidrológicas; mientras que M. luisana se localiza en tres provincias y dos cuencas; ambas coinciden en las provincias del Eje Volcánico y la Sierra Madre del Sur. Los modelos de distribución potencial se consideran excelentes, ya que poseen un AUC de 0.91 y 0.97, respectivamente. Los modelos indican que las condiciones de temperatura y precipitación son propicias para que ambos taxa pudieran ampliar su distribución. Igualmente, los modelos generados pueden considerarse como una aproximación al conocimiento de la distribución potencial de las mimosas mexicanas. Aunque, es importante considerar que los modelos son estáticos y no consideran a las interacciones bióticas, por lo que su relación con la realidad puede variar; por lo que se recomienda analizar los modelos mediante diferentes escenarios de cambio climático y de uso de suelo.


Abstract Mimosa aculeaticarpa var. aculeaticarpa and M. luisana are endemic to Mexico, and are considered as multipurpose plants, due to the diverse services they offer to ecosystems and to local people. Additionally, they are appreciated for their potential to restore tropical environments; hence, the objective of this study was to model the present and potential distribution of these taxa. In 2014, species registers were obtained from two databases (CONABIO and MEXU); each register was taxonomically, geographically and statistically validated. Once validated, the present and potential distribution of M. aculeaticarpa var. aculeaticarpa (based on 99 registers) and M. luisana (based on 50 registers) were obtained using the MAXENT algorithm. For both taxa, the present distribution was overlapped using the layers of: elevation, climate, soil, biogeographic provinces, and hydrologic basins. Mimosa aculeaticarpa var. aculeaticarpa showed a wide distribution in Mexico (16 states); whilst M. luisana was restricted to the states of Puebla and Oaxaca. M. aculeaticarpa var. aculeaticarpa establishes between 1 900 and 2 700 masl, and M. luisana between 500 and 1 760 masl. Both species were established in arid and semiarid climates; however, M. aculeaticarpa var. aculeaticarpa can also be found in temperate and mesic climates. Moreover, both taxa are distributed in calcareous regosol soils; although, M. aculeaticarpa var. aculeaticarpa is also found in eutric regosol, chromic vertisol and haplic phaeozem. The distribution of M. aculeaticarpa var. aculeaticarpa includes eight biogeographic provinces and three hydrologic basins; whilst M. luisana was only located in three provinces and two hydrologic basins; both are present in the Eje Volcánico and Sierra Madre del Sur provinces. The potential distribution models are considered as excellent ones due to an AUC of 0.91 and 0.97, respectively; these models indicated that the temperature and precipitation conditions would be suitable for the enlargement of their distribution. Likewise, these models can be considered an approach to the potential distribution knowlegment of the Mexican mimosas. Nevertheless, it is important to note that the models are static and do not take into account any biotic interaction; therefore, their relationship with reality can vary. Thus, it is recommended to analyze the models through different climate change and land use scenarios. Rev. Biol. Trop. 66(1): 321-335. Epub 2018 March 01.

13.
Biota Neotrop. (Online, Ed. ingl.) ; 18(1): e20170409, 2018. tab, graf
Article in English | LILACS | ID: biblio-951142

ABSTRACT

Abstract Accurate distributional information is crucial for studies on systematics, biodiversity and conservation. To improve the knowledge regarding the geographical distribution of Omalonyx in South America, we present updated information based on data from a literature review, institutional collections and malacological surveys. All this information composed the dataset used to predict species distribution employing the Maximum Entropy Algorithm (MaxEnt). The model was run using data on species distribution, altitude and bioclimatic variables (WorldClim database). The model had consistent performance, and areas presenting similar conditions to areas where the species were recorded were considered areas of occurrence. The predicted occurrence areas included those that were already surveyed and those that are considered potential occurrence areas. The results demonstrate that the genus has widespread distribution in the Neotropical region and occurs in the tropical, temperate and arid regions of South America and Lesser Antilles. Omalonyx spp. were recorded in all South American countries and hydrographic regions. However, in some countries, there were only isolated records (ex: Colombia and Ecuador). Here, we also present the first record of Omalonyx spp. in four Brazilian States (Acre, Rondônia, Piaui, and Amapá). The genus was found in all hydrographic regions within Brazil and among 27 federative unities; it was absent from only two unities (Roraima State and Distrito Federal). This work contributes to the knowledge on Omalonyx spp. distribution and provides an important basis for the work of ecologists and taxonomists.


Resumo A informação precisa sobre a distribuição é crucial para os estudos sobre sistemática, biodiversidade e conservação. Para melhorar o conhecimento sobre a distribuição geográfica de Omalonyx na América do Sul, apresentamos informações atualizadas com base em dados de revisão de literatura, coleções institucionais e pesquisas malacológicas. Toda essa informação compôs o conjunto de dados usado para predição da distribuição de espécies empregando o Algoritmo de Entropia Máxima (MaxEnt). O modelo foi executado usando dados de distribuição de espécies, altitude e variáveis bioclimáticas (banco de dados WorldClim). O modelo apresentou um desempenho consistente e as áreas que apresentaram condições semelhantes às áreas onde as espécies foram registradas, foram consideradas áreas de ocorrência. As áreas de ocorrências previstas incluíram aquelas que já foram pesquisadas e aquelas que são consideradas áreas de ocorrência potencial. Os resultados demonstram que o gênero tem uma distribuição Neotropical ampla e que ocorre nas regiões tropical, temperada e árida da América do Sul e nas Pequenas Antilhas. Omalonyx spp. foram registradas em todos os países e bacias sul-americanas. No entanto, em alguns países, apenas registros isolados foram encontrados (ex: Colômbia e Equador). Aqui, também apresentamos o primeiro registro de Omalonyx spp. em quatro estados brasileiros (Acre, Rondônia, Piauí e Amapá). O gênero foi encontrado em todas as regiões hidrográficas no Brasil e nas 27 unidades federativas; sendo ausente em apenas duas unidades federativas (Estado de Roraima e Distrito Federal). Esse trabalho contribui para o conhecimento da distribuição das espécies de Omalonyx e fornece uma importante base para trabalhos de ecólogos e taxonomistas.

14.
Chinese Traditional and Herbal Drugs ; (24): 4138-4143, 2018.
Article in Chinese | WPRIM | ID: wpr-851739

ABSTRACT

Objective To study the estimating reserves of wild Dipsacus chinensis and provide a new method for the Chinese materia medica (CMM) resource quantitative evaluation. Methods The major contributing factors for ecological distribution of developing potentiality medicinal plants of D. chinensis were screened on the GIS platform by using the MaxEnt model, and raster data of species density and individual biomass of D. chinensis were generated by MaxEnt model and patial interpolation technology based on the field survey data. Spatial quantitative analysis and assessment of the distribution of resources of D. chinensis was performed by using ArcGIS. On this basis, a reserves assessment model was formatted for sustainable utilization of CMM resources evaluation. Results The analysis showed that the distribution area of D. chinensis was about 3.34 × 105 km2 which was mainly distributed in Hengduan Mountains and the Qinghai Plateau southeast area, and resources reserves was about 3.08 × 107 kg. The results showed that more than 69.48% resources of D. chinensis was located in Sichuan Province, and the western Sichuan such as Aba, Ganzi, and Liangshan prefectures was the highly populated areas. According to that regional center into the surrounding showed a trend of decline, the overall characteristic of individual biomass geographic distribution showed an increased trend from the vertical plane of the Hengduan Mountains as interface to both sides. The results also indicated that seasonal temperature variation coefficient, annual average temperature range, and average rainfall in April were the dominant factors contributing to the underground biomass accumulation. While mean temperature in December, monthly average rainfall in July and August were negative correlated with the underground biomass accumulation. Conclusion This study provides strong data support for the development and utilization of new resources of wild D. chinensis, and helps to establish a new way to the visual quantitative evaluation of CMM resources.

15.
China Journal of Chinese Materia Medica ; (24): 3658-3661, 2018.
Article in Chinese | WPRIM | ID: wpr-689864

ABSTRACT

Based on the distribution information of 110 samples and 55 environmental factors, Maxent model was used to predict the ecology suitability regions of Trollius chinensis. The study aims at providing theory basis for the cultivation of T. chinensis. The results showed that the Maxent model prediction result was good (AUC>0.9) and the main factors effecting the ecology suitability regions of T. chinensis were precipitation in July, standard deviation of seasonal variation of temperature, annual mean temperature, precipitation in August and altitude. The ecology suitable regions of T. chinensis mainly concentrated in Shanxi, Hebei, east of Inner Mongolia, west of Jilin and Liaoning, north of Shaanxi, south of Ningxia, east and south of Gansu, and east of Qinghai. The results indicated that except for traditional distribution regions, north of Shaanxi, south of Ningxia, east and south of Gansu, and east of Qinghai could selected as the regions for cultivation of T. chinensis. It provides theory basis for selecting suitable regions to cultivate T. chinensis.

16.
Braz. j. biol ; 77(4): 686-695, Nov. 2017. tab, graf
Article in English | LILACS | ID: biblio-888819

ABSTRACT

Abstract Ecological niche modeling has contributed to the investigation of the geographical distribution and conservation of rare or little recorded species. Therefore, we studied the known and potential distributions of Colobosauroides carvalhoi Soares and Caramaschi 1998 and discuss the implications for its conservation. Data were obtained by manual collections made in quarterly samplings in three different regions, considering the regions with occurrence records and surrounding areas. The known distribution was determined by occurrence records and literature data, and potential distribution was estimated with an ecological niche model by the MaxEnt algorithm. Twenty-five specimens were collected exclusively in forest formations of Caatinga and Caatinga-Cerrado. Our data corroborated the relative rarity of C. carvalhoi and reflected the biogeographical history of the group, where it is restricted to forest formations with milder environmental conditions. The occurrence records indicated new records of C. carvalhoi, but the known distribution value is compatible with a restricted distribution. The ecological niche model estimated few areas with environmental suitability for the species and corroborated the restricted and relict distribution patterns. Finally, the known and potential distribution values ​​were compatible with criteria for threatened species. These results suggest a worrisome scenario for C. carvalhoi conservation. However, the limited data about the species population do not allow the proper definition of its conservation status. Therefore, we suggest using potential distribution values with alternative criteria for redefining the conservation status of C. carvalhoi and the development of new studies that support a better assessment of its conservation aspects.


Resumo A modelagem ecológica de nicho vem contribuindo para investigar a distribuição geográfica e conservação de espécies raras ou com poucos registros de ocorrência. Neste sentido, investigou-se a distribuição conhecida e potencial da espécie Colobosauroides carvalhoi Soares & Caramaschi, 1998, discutindo as implicações para a conservação da espécie. Os dados foram coletados por meio de coletas manuais realizadas em amostragens trimestrais realizadas em três regiões distintas, considerando as regiões com registros de ocorrência conhecidos e áreas adjacentes. A distribuição conhecida foi determinada a partir dos novos registros de ocorrência e dados da literatura e a distribuição potencial estimada por meio de um modelo ecológico de nicho com uso do algoritmo MaxEnt. Vinte e cinco exemplares da espécie C. carvalhoi foram coletados exclusivamente em formações arbóreas da Caatinga e áreas de interface entre a Caatinga e o Cerrado. Estes resultados corroboram a relativa raridade da espécie e refletem a história biogeográfica do grupo, relacionada a ambientes florestados e que apresentam condições ambientais mais amenas. Os registros de ocorrência de C. carvalhoi indicam novos registros, entretanto, o valor de distribuição conhecida foi compatível com valores de distribuição restrita. O modelo ecológico de nicho estimou poucas áreas adequadas à ocorrência da espécie, corroborando um padrão de distribuição restrita e relictual. Por fim, os valores de distribuição conhecida e potencial estimados são compatíveis com valores definidos para espécies ameaçadas. Estes resultados sugerem um cenário preocupante para a conservação de C. carvalhoi. Entretanto, a atual limitação de dados populacionais dificulta uma adequada avaliação de seu status de conservação. Portanto, sugerimos o uso dos valores de distribuição potencial como critério alternativo para avaliar seu status de conservação até que novos estudos possam subsidiar uma melhor avaliação da conservação da espécie.


Subject(s)
Animals , Conservation of Natural Resources , Animal Distribution , Lizards , Brazil , Endangered Species , Models, Biological
17.
China Journal of Chinese Materia Medica ; (24): 4368-4372, 2017.
Article in Chinese | WPRIM | ID: wpr-338267

ABSTRACT

This paper is aimed to clarify the distribution of Codonopsis Radix in China and search the main ecological factors that affect the suitability distribution. Through literature reading, National Specimen Information Infrastructure researching, field investigation and general survey of Chinese medicine resources, the distribution information was acquired. The MaxEnt model and ArcGIS technology were applied to analyze the main environmental factors influencing the suitability of Codonopsis Radix with integrated 55 environmental factors. The results showed the precipitation and altitude were the major factors impacting the ecology suitable of Codonopsis Radix. The ecological suitable region of C. pilosula was mainly concentrated in south Gansu, Shanxi, Shanxi, Ningxia and, and the ecological suitable region of C. pilosula var. modesta was mainly concentrated in south Gansu, northwest Guizhou, northeast Sichuan, and the ecological suitable region of C. tangshen was mainly concentrated in west Hubei, east Chongqing, middle Sichuan. Combined with the investigation and cultivation of Codonopsis Radix distribution information, the results of ecological suitability of Codonopsis Radix were verified. The ecological suitability distribution result of Codonopsis Radix was consistent with each species actual distribution, which could provide scientific basis for carrying out the rational cultivation of Codonopsis Radix.

18.
China Journal of Chinese Materia Medica ; (24): 4373-4377, 2017.
Article in Chinese | WPRIM | ID: wpr-338266

ABSTRACT

At the urgent practical issue of resource protection and artificial cultivation area selection of Dioscorea nipponica, the dominant environmental factors affecting the distribution of D. nipponicain Jilin province were selected by field investigation and using the maximum information entropy model and geographic information technology. MaxEnt model study found that the standard deviation of seasonal variation of temperature, precipitation in October and other six environmental factors on the growth of D. nipponica are the greatest impacting factors. The range of suitability for the growth of D. nipponica was 4.612 08×10-6-0.544 31, and the regionalization study was divided into four parts: high fitness area, middle fitness area, low fitness area and unfavorable area. The high fitness area is concentrated in the central and southern areas of Jilin Province, using ArcGIS statistical environment factors in the appropriate area of the numerical situation. The results showed that the regionalization study of D. nipponica was basically the same as the actual situation. It is clear that the natural environment suitable for the growth of D. nipponica is also the basis for the protection of the resources and the selection of cultivated area.

19.
China Journal of Chinese Materia Medica ; (24): 4395-4401, 2017.
Article in Chinese | WPRIM | ID: wpr-338263

ABSTRACT

Research on predictive distribution and planting GAP of Cyathula officinalis in China is helpful to provide scientific basis for its protection and planting popularization. According to the data in 63 distribution sites and 49 ecological variables, using MaxEnt ecological niche model and 3S technology, we performed a quantitative analysis of suitable distribution and planting GAP of C. officinalis in China. Our results show that: ① the area of suitable distribution of C. officinalis is about 634 385.80 km² in total, and mainly in Northeastern and Southeastern Sichuan, Northern and Southeastern Yunnan, Western and Southwestern Guizhou, Southwestern and Northeastern Chongqing, Southwestern Shaanxi, Southeastern Gansu, Western Guangxi, Southeastern Tibet. ② The main ecological factors determining the potential distribution are precipitation, altitude, minimum temperature of coldest month, soil type, monthly mean temperature. ③ The planting GAP region are mainly in Guangyuan, Mianyang, Ya'an, Leshan, Liangshan, Panzhihua of Sichuan province, Hanzhong of Shaanxi province, Dali, Nujiang, Chuxiong, Baoshan, Qujing, Wenshan of Yunnan province, southwestern autonomous prefecture in Guizhou province. The results are of great significance for realizing the growth environment, predicting the potential distribution and promoting planting popularization for C. officinalis.

20.
China Journal of Chinese Materia Medica ; (24): 1118-1124, 2017.
Article in Chinese | WPRIM | ID: wpr-350216

ABSTRACT

Apocynum venetum belongs to apocynaceae and is a perennial medicinal plant, its stem is an important textile raw materials. The projection of potential geographic distribution of A. venetum has an important significance for the protection and sustainable utilization of the plant. This study was conducted to determine the potential geographic distribution of A. venetum and to project how climate change would affect its geographic distribution. The projection geographic distribution of A. venetum under current bioclimatic conditions in northern China was simulated using MaxEnt software based on species presence data at 44 locations and 19 bioclimatic parameters. The future distributions of A. venetum were also projected in 2050 and 2070 under the climate change scenarios of RCP2.6 and RCP8.5 described in 5th Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). The result showed that min air temperature of the coldest month, annual mean air temperature, precipitation of the coldest quarter and mean air temperature of the wettest quarter dominated the geographic distribution of A. venetum. Under current climate, the suitable habitats of A. venetum is 11.94% in China, the suitable habitats are mainly located in the middle of Xinjiang, in the northern part of Gansu, in the southern part of Neimeng, in the northern part of Ningxia, in the middle and northern part of Shaanxi, in the southern part of Shanxi, in the middle and northern part of Henan, in the middle and southern part of Hebei, Shandong, Tianjin, in the southern part of Liaoning and part of Beijing. From 2050 to 2070, the model outputs indicated that the suitable habitats of A. venetum would decrease under the climate change scenarios of RCP2.6 and RCP8.5.

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