scholarly journals Impact de la Phénologie des Espèces Ligneuses Préservées de Savane sur L’évolution des Milieux Modifiés par L’activité Anthropique dans le Nord-Est Ivoirien. L’exemple des Savanes Soudaniennes de la Région de Bouna

2021 ◽  
Vol 17 (37) ◽  
pp. 69
Author(s):  
Kambire Sambi
Keyword(s):  
Rural Communities ◽  
Rainy Season ◽  
Woody Species ◽  
Dry Season ◽  
Environmental Resources ◽  
Protected Species ◽  
Phenological Stages

Les savanes soudaniennes sont caractérisées par les groupements d’arbres utiles protégés, organisés en vergers ou en parcs. Ces ligneux conduisent à un retour remarquable à la physionomie originelle des divers faciès de végétation profondément modifiés à travers l’apparition et la chute de leurs feuilles, fleurs et fruits. On peut alors s’interroger sur le rôle de ces phases phénologiques dans la restauration des milieux transformés par l’activité anthropique. Cette étude vise à montrer le processus de régénération des milieux transformés par l’homme à partir des cycles phénologiques des ligneux épargnés par les défrichements. Elle contribue à améliorer la capacité des communautés rurales à planifier et à gérer durablement les ressources environnementales en savanes soudaniennes. Elle repose sur le postulat d’une restauration des faciès des milieux végétaux modifiés à partir de la dissémination du stock au sol des organes des diverses espèces protégées. L’analyse des stades phénologiques de ces espèces ligneuses est effectuée à partir de relevés réalisés tous les 15 jours du début de la saison sèche à la fin de l’hivernage. Les résultats indiquent que leurs recrûs verts, à partir des fruits disséminés ou des racines, permettent la reconquête ligneuse des milieux abandonnés à la jachère. The sudanese savannahs are characterized by useful protected species of trees, organized in orchards or parks. This woody stand involves remarkable modifications of the physiognomy of the different facies of the vegetation by appearance and fall of their leaves, flowers and fruits. We can therefore wonder about the role of these phenological modifications in restoring the environments modified by humans. This study aims to show the process of regeneration of environments transformed by humans from the phenological cycles of the ligneous species spared by clearing. It contributes to improving the capacity of rural communities to plan and sustainably manage environmental resources in the sudanese savannahs. It is based on postulate of a restoration of facies of transmormed plant environments from dissemination of the stock on soil of the organs of the various protected species. The phenological stages of these woody species are analyzed on the basis of surveys carried out every two weeks from the start of the dry season to the end of the rainy season. The results show that their green regrowth, from scattered fruits or roots, allow the woody reconquest of environments abandoned to fallow.

Seasonal movements of giraffes in Niger

1999 ◽  
Vol 15 (3) ◽  
pp. 341-353 ◽  
Author(s):  
Yvonnick Le Pendu ◽  
Isabelle Ciofolo
Keyword(s):  
Rural Communities ◽  
Rainy Season ◽  
Dry Season ◽  
Home Ranges ◽  
Spatial Behaviour ◽  
Long Distance ◽  
Mean Size ◽  
The Mean ◽  
Niger River ◽  
Hydrographic Network

The last population of giraffes in west Africa lives in Niger in an unprotected Sahelian region inhabited by farmers and herders. The spatial behaviour of each individual of the population (n = 63) was studied by direct observation during 15 mo. Two-thirds of the population were resident in the tiger bush in the rainy season and in the nearby area of Harikanassou, a sandy agricultural region, in the dry season. Rainy season and dry season home ranges were mutually exclusive and individual home ranges were overlapping when considering one season (rainy season: 84%; dry season: 67%). The mean size of the seasonal home ranges of these resident giraffes during the dry season (90.7 km2) was twice the mean size during the rainy season (46.6 km2). A third of the population moved 80 to 200 km in three directions, and two giraffes from an isolated group from Mali moved 300 km along the Niger River. Long distance movements of such length have never been reported before, and several explanations are proposed: previous distribution, social transmission, hydrographic network and food availability, poaching events. The giraffes in Niger do not avoid rural communities; indeed, they live in densely populated regions. Furthermore, their movements, synchronized with human activities in these regions, are representative of life conditions in the Sahel.

scholarly journals Effects of seasonal upwelling on hydrography and mesozooplankton communities in a Pacific tropical cove off Colombia

2019 ◽  
Vol 67 (4) ◽  
Author(s):  
Bellineth Valencia ◽  
Alan Giraldo ◽  
Marisol Rivera-Gómez ◽  
Vanessa Izquierdo ◽  
Andrés Cuellar-Chacón
Keyword(s):  
Water Column ◽  
Seasonal Changes ◽  
Rainy Season ◽  
Physiological Stress ◽  
Dry Season ◽  
Coastal Zones ◽  
Subsurface Waters ◽  
Northern Pacific ◽  
Field Campaigns

Introduction: The effects of seasonal upwelling on the conditions of the water column and mesozooplankton communities are poorly understood in the coastal zones of the Eastern Tropical Pacific (ETP), despite the important role of upwelling events in the modulation of productivity in these zones. Objective: To evaluate the influence of seasonal upwelling over the Panama Bight on the structure of the water column and mesozooplankton communities in a tropical cove of the ETP. Methods: Hydrographic data and mesozooplankton samples were collected during four field campaigns in Ensenada de Utría (December 2011, February 2012, October 2013, and February 2013), an estuary located in the Northern Pacific coast of Colombia. Non-parametric and multivariate analyses were used to evaluate seasonal differences in the environmental and biotic variables. Results: Surface waters were warm (> 25 °C) and presented low salinities (< 30) throughout the study period. In contrast, subsurface waters were colder (< 20 °C), saltier (> 33), and presented low dissolved oxygen concentrations (< 2.0 ml l-1) during the dry season (January - March), whereas the water column was homogeneous during the rainy season (April - December). Despite the seasonal changes in the environmental conditions, the expected enhancement in the productivity of the system during the dry season (i.e., higher biomass and abundance of the mesozooplankton) only occurred in February 2012. Contrary to expectations, ichthyoplankton abundance was higher during the rainy season, when the assemblage was dominated by the larvae of anchovy (Cetengraulis mysticetus) and an unidentified Gobiidae. Conclusions: The entrance of upwelled waters into Ensenada de Utría is an important factor modulating the seasonal changes observed in the water column. However, there is high interannual variability in the response of mesozooplankton communities to the upwelling events. Because upwelled waters are oxygen-depleted and more acidic, the entrance of upwelled waters into Ensenada de Utría could be causing physiological stress to the benthic and pelagic organisms inhabiting the deepest zones of the cove. This condition may worsen in the future given the predicted increase of deoxygenation and ocean acidification due to climate change.

scholarly journals Caatinga Albedo Preserved and Replaced by Pasture in Northeast Brazil

Atmosphere ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1622
Author(s):  
Alcindo Mariano Souza ◽  
Cláudio Moisés Santos e Silva ◽  
Bergson Guedes Bezerra
Keyword(s):  
Rainy Season ◽  
Early Morning ◽  
Dry Season ◽  
Pasture Management ◽  
Seasonally Dry ◽  
Temperature And Precipitation ◽  
Local Standard ◽  
The Mean ◽  
Dry And Rainy Seasons

The caatinga is considered South America’s largest seasonally dry tropical forest (SDTF) and one of the most vulnerable endemic biomes in relation to climate change. The surface albedo in caatinga is relevant to understanding the role of this biome in the climate of the Northeast region of Brazil. Thus, a comparative analysis was conducted between the albedos of preserved and anthropized caatinga (pasture). Data were collected using CNR4-type net radiometers during the dry and rainy seasons. The mean albedo values were higher in the Pasture both in the dry and rainy season, with values of 0.181 and 0.177, respectively. In the caatinga, the mean albedo values were 0.137 in the dry season and 0.146 in the rainy season. The hourly average values for albedo, taken between 6:30 a.m. and 4 p.m., with intervals of 30 min, were also higher in the pasture. For convenience, this study uses local standard time (LST), which is 3 h behind from coordinated universal time (UTC). The greatest dispersions in the frequencies of the mean hourly albedo values occurred in the early morning and late afternoon. Some of the consequences of this study is the confirmation that there is an increase in albedo in caatinga replaced by pasture and this causes a reduction in the net radiation and also the finding that a region where there is adequate pasture management also enables albedo management and from solar radiation. And that further studies can indicate the impacts on temperature and precipitation, especially in warmer periods during the dry season.

scholarly journals Conserving a globally threatened species in a semi-natural, agrarian landscape

Oryx ◽  
2017 ◽  
Vol 53 (1) ◽  
pp. 181-191 ◽  
Author(s):  
Harriet Ibbett ◽  
Chansetha Lay ◽  
Ponlork Phlai ◽  
Det Song ◽  
Chamnan Hong ◽  
...  
Keyword(s):  
Rural Communities ◽  
Local Communities ◽  
Dry Season ◽  
Rice Cultivation ◽  
Breeding Habitat ◽  
Human Populations ◽  
Tonle Sap ◽  
Local Livelihood ◽  
The Tropics

AbstractAgriculture threatens biodiversity across the tropics, particularly in semi-natural grassland landscapes, where human populations are high, habitat is easily converted and agriculture is prone to intensification. Over the last 20 years intensive, commercial dry season rice cultivation has emerged as the dominant threat to the Bengal florican Houbaropsis bengalensis, a globally threatened bustard that breeds in the seasonally inundated grasslands of central Cambodia. Although floricans have been extensively monitored for 10 years, no socioeconomic research has been undertaken to examine how local livelihood activities interact with the florican. We conducted household questionnaires and focus groups in 21 villages in the Northern Tonle Sap Conservation Landscape to gather information on household demographics, rice farming and bird hunting in protected and unprotected areas of florican breeding habitat. We identified a significant increase in dry season rice adoption by local communities since 2005. Dry season rice cultivation was strongly associated with agrochemical use and rice fields directly overlapped with florican breeding habitat, reducing habitat availability throughout the breeding season. We identified a low but significant level of bird hunting in grassland households (8%) and revealed a demand for wild bird meat amongst local communities. Our findings suggest an urgent need for conservation interventions in unprotected farmland and emphasize the role of enforcement and community engagement in improving protection within protected areas. We highlight the potential of private sector initiatives such as the Sustainable Rice Platform in reconciling conservation and development for impoverished rural communities.

scholarly journals Reproductive phenological patterns of cerrado plant species at the Pé-de-Gigante Reserve (Santa Rita do Passa Quatro, SP, Brazil): a comparison between the herbaceous and woody floras

2000 ◽  
Vol 60 (1) ◽  
pp. 129-145 ◽  
Author(s):  
M. A. BATALHA ◽  
W. MANTOVANI
Keyword(s):  
Plant Species ◽  
Rainy Season ◽  
Vascular Plant ◽  
Woody Species ◽  
Dry Season ◽  
Natural Vegetation ◽  
Reproductive Stage ◽  
Southeastern Brazil ◽  
Floristic Survey ◽  
Paulo State

A natural vegetation area, with 1269 ha, composed mainly by cerrado, located at Santa Rita do Passa Quatro Municipality, São Paulo State, southeastern Brazil (21°36-39'S, 47°36-38'W), was studied. From September 1995 to February 1997, a floristic survey was carried out, when all vascular plant species at reproductive stage were collected. The flowering and fruiting patterns of the community were studied, comparing the herbaceous and the woody species. In the herbaceous component, 239 species were found and, in the woody one, 108 species. The woody species flowered mainly at the beginning of the rainy season, while the herbaceous ones produced flowers generally at the end of that season. The proportion of anemo and autochorous species was greater in the herbaceous component. The zoochorous ones, on the contrary, were more frequent in the woody component. At the dry season, when their dispersion is more efficient, the proportion of anemo and autochorous species producing fruits was higher. During the rainy season, when their fruits become attractive for longer time, the zoochorous species fruited more intensely.

scholarly journals Ecology of Anopheles Mosquito Larvae in Different Ecological Zones in Ghana

2021 ◽  
Author(s):  
Isaac Amankona Hinne ◽  
Simon Kwaku Attah ◽  
Benedicta Ayiedu Mensah ◽  
Akua Obeng Forson ◽  
Yaw Asare Afrane
Keyword(s):  
Rural Communities ◽  
Rainy Season ◽  
Anthropogenic Activities ◽  
Temporal Distribution ◽  
Larval Habitat ◽  
Dry Season ◽  
Effective Control ◽  
Mosquito Larvae ◽  
Ecological Zones ◽  
Breeding Habitats

Abstract Background: Understanding the ecology of larval malaria mosquitoes is important in a changing environment is important in developing effective control tools or programmes. This study characterized the breeding habitats of Anopheles mosquitoes in rural communities in different ecological zones in Ghana during the dry and rainy seasons.Methods: The spatio-temporal distribution, species composition, and abundance of larval Anopheles mosquitoes in breeding habitats were studied in 3 ecological zones of Ghana. These were Anyakpor (Coastal Savanna area), Duase (Forest area), Libga, Pagazaa, and Kpalsogu (Sahel Savanna area). Larvae were collected using standard dippers and were raised in the insectary for identification. Results: Out of a total of 7,984 mosquito larvae collected, 2,152 (27.26%) were Anophelines and were more abundant in the rainy season (70.82%) than in the dry season (29.18 %). The Anophelines were made up of 2,128 (98.88%) An. gambiae s.l., 16 (0.74%) An. rufipees and 8 (0.37%) An. pharoensis. In Anyakpor and Duase, dug-out wells were the most productive habitat in the dry (1.59 larvae/dip and 1.47 larvae/dip) and rainy seasons (11.28 larvae/dip and 2.05 larvae/dip). The most productive habitats in Kpalsogu were natural ponds in the dry season (0.89 larvae/dip) and swamps in the rainy season (2.57 larvae/dip). In Libga, the most productive habitats were drainage ditches in the dry season (0.30 larvae/dip) and furrows in the rainy season (1.83 larvae/dip). The most productive habitats in Pagazaa were puddles (1.44 larvae/dip). Anopheles coluzii was the most abundant sibling species in all the ecological zones except Libga in the sahel savannah area where An. gambiae s.s was the most abundant. Anopheles melas and An. arabiensis were encountered only in the coastal savannah and the sahel savanna areas respectively. Larval habitat types influenced the presence of larvae as well as larval densities (p < 0.001). The land-use type affected the presence of Anopheles larvae (p = 0.001), while vegetation cover influenced larval densities (p < 0.05). Conclusion: The study revealed that the abundance of Anopheles breeding habitats and hence Anopheles larvae are closely associated with anthropogenic activities. Regulating such activities will lead to a significant reduction in Anopheles breeding habitats.

scholarly journals Implications of soils around domestic water points in the spread of intestinal parasites in the city of Yaounde (Cameroon)

2018 ◽  
Vol 17 (2) ◽  
pp. 318-328
Author(s):  
Ajeagah Gideon Aghaindum ◽  
Asi Quiggle Atud ◽  
Okoa Amougou Thérèse Nadège
Keyword(s):  
Rainy Season ◽  
Intestinal Parasites ◽  
Epidemiological Studies ◽  
Average Density ◽  
Dry Season ◽  
Domestic Water ◽  
Scientific Methods ◽  
Short Rainy Season ◽  
Ancylostoma Duodenale

Abstract To determine the role of soils in dissemination of enteric protozoan cysts and intestinal eggs and/or larvae of helminths, a study was carried out on muddy soils around springs and wells of six districts in Yaounde, Cameroon from February to July 2015. Protozoan cysts and helminth eggs and larvae were observed microscopically after concentration by standard scientific methods. Flagellated enteric protozoa cysts were detected at an average density of 245 ± 145 cysts/L for Giardia intestinalis, 308 ±190 cysts/L for Chilomastix mesnili, 105 ± 106 cysts/L for Enteromonas hominis and 96 ± 118 cysts/L for Retortamonas intestinalis. Cyst densities were higher during the short rainy season (277 ± 119 cysts/L) than in the short dry season (147 ± 60 cysts/L). The helminths identified were Ascaris sp., Enterobius sp., Necator americanus and/or Ancylostoma duodenale, Strongyloides sp., Taenia sp., Hymenolepis sp., Diphyllobothrium sp. and Fasciola sp. Size varied between 40 μm and 200 μm for eggs and between 100 μm and 600 μm for the larvae assessed. Densities of environmental forms of the helminths were also higher during the short rainy season (176 ± 77 agents/L) than during the short dry season (117 ± 49 agents/L). These results show that muddy soils could contribute to the contamination of wells and springs and should be considered in epidemiological studies of intestinal parasites.

Aseuk Hatong Antara Seni Berkomunikasi dan Teknologi: Studi Fenomenologi tentang Budaya Bertani Ladang Masyarakat Tatar Karang Priangan Kabupaten Tasikmalaya

Metahumaniora ◽  
2017 ◽  
Vol 7 (3) ◽  
pp. 332
Author(s):  
Samson CMS
Keyword(s):  
Rainy Season ◽  
Research Method ◽  
Technology Development ◽  
Appropriate Technology ◽  
Musical Aesthetics ◽  
Research Show

ABSTRAKTidak mampunya kita mendalami pengetahuan asli kita sendiri mengakibatkanterjadinya disharmoni teknologi dengan kebutuhan di lapangan, tidak terkecuali TeknologiTepat Guna (TTG) dalam pertanian ladang. Tujuan penelitian ini adalah untuk mengetahuiperanan Aseuk Hatong dalam tradisi pertanian ladang di masyarakat Tatar Karang PrianganKabupaten Tasikmalaya yang religius Islami, tapi masih mempertahankan tradisi tersebut.Metode penelitian ini menggunakan studi fenomenologi Schutz. Hasil penelitian menunjukkanbahwa 1) Seni berkomunikasi: (kakawihan) dalam tradisi Aseuk Hatong adalah upayaharmonisasi antara petani dengan alam yang sedang kemarau melalui senandung ringan yangkontekstual. 2) Teknologi Tani: (Aseuk Hatong) adalah suatu alat untuk mengolah untuk tanahladang pada musim kemarau yang dibalut dengan estetika musikal sederhana khas petaniladang, hasil pengembangan teknologi yang tepat guna, menyenangkan, inovatif, fungsional,terjangkau, murah, dan ramah lingkungan. Dengan demikian, dapat dirumuskan bahwa TradisiAseuk Hatong di Tatar Karang Priangan merupakan media persuasif bertani di kala ngahuma(berladang) tidak dibarengi musim penghujan. Tradisi Aseuk Hatong juga merupakanpengembangan teknologi yang sangat memperhitungkan kearifan lokal yang berlaku.Kata kunci: aseuk hatong, kawih, komunikasi seni, teknologi tani, pertanian ladangABST RACTOur inability to deepen our own original knowledge results in disharmony of technologywith the needs in the field, including the Appropriate Technology (TTG) in agriculture. It istherefore that in any development it is often not harmonious with the needs of society. Theobjective of the research is to know the role of Aseuk Hatong in the agricultural tradition in theTatar Karang Priangan community of Tasikmalaya Regency whicht is religiously Islamic yetstill maintains the tradition. The research method is Schutz phenomenology study. The resultsof research show that (1) the art of communicating (kakawihan) in Aseuk Hatong tradition isa harmonious effort between farmers and the dry nature through mild, contextual humming.(2) Farm technology (Aseuk Hatong)is a tool to cultivate the soil, plowing the fields during thedry season by wrapping with simple typical musical aesthetics of field farmers as the resultsof appropriate technology development, fun, innovative, functional, affordable, cheap, andenvironmentally friendly. As the conclusion, it can be said that Aseuk Hatong Tradition in TatarKarang Priangan as a persuasive media farming during ngahuma (farming) not accompaniedby rainy season is a technology development that takes into account local wisdom occur.Keywords: aseuk hatong, kawih, art communication, farming technology

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,

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