Effects of extra food on population fluctuation patterns of the muroid rodent Calomys venustus

2002 ◽  
Vol 27 (3) ◽  
pp. 273-283 ◽  
Author(s):  
F. Castellarini ◽  
J. Polop
Keyword(s):  
Population Fluctuation ◽  
Extra Food ◽  
Muroid Rodent

scholarly journals Impact of the COVID-19 pandemic on agricultural production, livelihoods, and food security in India: baseline results of a phone survey

Food Security ◽  
2021 ◽  
Author(s):  
Lindsay M. Jaacks ◽  
Divya Veluguri ◽  
Rajesh Serupally ◽  
Aditi Roy ◽  
Poornima Prabhakaran ◽  
...  
Keyword(s):  
Food Security ◽  
Agricultural Production ◽  
Dietary Diversity ◽  
The Past ◽  
Phone Survey ◽  
Extra Food ◽  
The Government ◽  
Time Of Year ◽  
Livestock Products ◽  
The Impact

AbstractThe aim of this study was to evaluate the impact of the COVID-19 lockdown on agricultural production, livelihoods, food security, and dietary diversity in India. Phone interview surveys were conducted by trained enumerators across 12 states and 200 districts in India from 3 to 15 May 2020. A total of 1437 farmers completed the survey (94% male; 28% 30–39 years old; 38% with secondary schooling). About one in ten farmers (11%) did not harvest in the past month with primary reasons cited being unfavorable weather (37%) and lockdown-related reasons (24%). A total of 63% of farmers harvested in the past month (primarily wheat and vegetables), but only 44% had sold their crop; 12% were still trying to sell their crop, and 39% had stored their crop, with more than half (55%) reporting lockdown-related issues as the reason for storing. Seventy-nine percent of households with wage-workers witnessed a decline in wages in the past month and 49% of households with incomes from livestock witnessed a decline. Landless farmers were about 10 times more likely to skip a meal as compared to large farmers (18% versus 2%), but a majority reported receiving extra food rations from the government. Nearly all farmers reported consuming staple grains daily in the past week (97%), 63% consumed dairy daily, 40% vegetables daily, 26% pulses daily, and 7% fruit daily. These values are much lower than reported previously for farmers in India around this time of year before COVID-19: 94–95% dairy daily, 57–58% pulses daily, 64–65% vegetables daily, and 42–43% fruit daily. In conclusion, we found that the COVID-19 lockdown in India has primarily impacted farmers’ ability to sell their crops and livestock products and decreased daily wages and dietary diversity.

Population Fluctuation and the Adoption of Food Production in Prehistoric Korea: Using Radiocarbon Dates as a Proxy for Population Change

Radiocarbon ◽  
2017 ◽  
Vol 59 (6) ◽  
pp. 1761-1770 ◽  
Author(s):  
Yongje Oh ◽  
Matthew Conte ◽  
Seungho Kang ◽  
Jangsuk Kim ◽  
Jaehoon Hwang
Keyword(s):  
Probability Distribution ◽  
Population Growth ◽  
Food Production ◽  
Population Change ◽  
Population Pressure ◽  
Population Fluctuation ◽  
Intensive Agriculture ◽  
Rice Farming ◽  
Radiocarbon Dates ◽  
Transition To Agriculture

AbstractPopulation growth has been evoked both as a causal factor and consequence of the transition to agriculture. The use of radiocarbon (14C) dates as proxies for population allows for reevaluations of population as a variable in the transition to agriculture. In Korea, numerous rescue excavations during recent decades have offered a wealth of14C data for this application. A summed probability distribution (SPD) of14C dates is investigated to reconstruct population trends preceding and following adoptions of food production in prehistoric Korea. Important cultivars were introduced to Korea in two episodes: millets during the Chulmun Period (ca. 6000–1500 BCE) and rice during the Mumun Period (ca. 1500–300 BCE). The SPD suggests that while millet production had little impact on Chulmun populations, a prominent surge in population appears to have followed the introduction of rice. The case in prehistoric Korea demonstrates that the adoption of food production does not lead inevitably towards sustained population growth. Furthermore, the data suggest that the transition towards intensive agriculture need not occur under conditions of population pressure resulting from population growth. Rather, intensive rice farming in prehistoric Korea began during a period of population stagnation.

scholarly journals TOMATO LEAF MINER, TUTA ABSOLUTA (LEP., GELECHIIDAE), POPULATION FLUCTUATION AND SEASONAL ACTIVITY IN THE FIELD

2020 ◽  
Vol 6 (8) ◽  
pp. 88-98
Author(s):  
Shahriar Asgari ◽  
Yaghoub Fathipour
Keyword(s):  
Larval Density ◽  
Pheromone Trap ◽  
Tomato Leaf ◽  
Tuta Absoluta ◽  
Population Fluctuation ◽  
Leaf Miner ◽  
Seasonal Activity ◽  
Tomato Field ◽  
Tomato Leaf Miner ◽  
Tehran Province

Seasonal activity and population fluctuation of tomato leaf miner, Tuta absoluta (Meyrick), a dangerous pest of tomato fields in Tehran province, were determined in Varamin region, south of Tehran province in 2015-2016. Number of moths in pheromone trap and number of larvae per plant were counted weekly in a trail tomato field. The trap capture began on mid-April in warm dry spring of 2015 and on mid-May in cool wet spring of 2016. The first and highest moth peaks in trap occurred about one month earlier in 2015 than 2016. The larval density per plant at the highest peak reached 2.34 and 10.8 in 2015 and 2016, respectively. A temperature range of 25-30°C was desirable to the pest in which the interval of successive peaks decreased. In both years, the pest created three generations over a growing season, according to larval peaks, but 11 over a year, according to trap data, that the 11th generation overwintered. The temperature of 35°C and above limited larval activity and decreased the population. After the crop removed, the pest population declined due to host shortage, but it increased with the access of hosts in the second cultivation since mid-September until the cold season.

scholarly journals Flutuação Populacional de Rhynchophorus palmarum L. (Coleoptera: Curculionidae) em Plantios de Palma de Óleo em Roraima

2015 ◽  
Vol 8 (2) ◽  
pp. 130-134 ◽  
Author(s):  
Ruy Guilherme Correia ◽  
Antonio Cesar Silva Lima ◽  
Antonio Carlos Centeno Cordeiro ◽  
Francisco Clemilto Da Silva Maciel ◽  
Walmer Bruno Rocha Martins ◽  
...  
Keyword(s):  
Aggregation Pheromone ◽  
Palm Oil ◽  
Oil Palm ◽  
Elaeis Guineensis ◽  
Cane Sugar ◽  
Population Fluctuation ◽  
Forest Environment ◽  
Rhynchophorus Palmarum ◽  
Elaeis Guineensis Jacq ◽  
Field Traps

Esta pesquisa teve como objetivo avaliar a flutuação populacional de Rhynchophorus palmarum L. (Coleoptera: Curculionidae) em plantios de Elaeis guineensis Jacq, em ecossistemas de savana e floresta no estado de Roraima. A pesquisa foi desenvolvida durante o período de janeiro de 2011 a fevereiro de 2012 nos campos experimentais da Embrapa Roraima: Monte Cristo e Caroebe, numa área de 2 hectares com a cultura da Palma de Óleo, em cada campo. Foram distribuídas armadilhas iscadas com roletes de cana-de-açúcar e feromônio de agregação para captura dos insetos no entorno dos plantios. Ocorreu flutuação de R. palmarum com picos populacionais nos meses de julho e agosto no ecossistema de savana e de abril a setembro no ambiente de floresta. A população de R. palmarum foi menor em meses de baixa precipitação pluviométrica nos dois ambientes avaliados com a Palma de Óleo em RoraimaPopulation Fluctuation of Rhynchophorus  palmarum  L.  (Coleoptera: Curculionidae) in Plantations of Oil Palm in RoraimaAbstract. This research aimed to evaluate the population fluctuation Rhynchophorus palmarum L. (Coleoptera: Curculionidae) in Elaeis guineensis Jacq plantations in forest and savanna ecosystems in the state of Roraima. The research was conducted during the period from January 2011 to February 2012 in the experimental field of Embrapa Roraima: Monte Cristo and Caroebe in an area of 2 hectares with culture Oil Palm in each field. Traps baited with rollers cane sugar and aggregation pheromone for capturing insects in the vicinity of the plantations were distributed. Fluctuation occurred R. palmarum with population peaks in the months of July and August in the savanna ecosystem and from April to September in the forest environment. The population of R. palmarum was lower in months of low rainfall in the two environments assessed with a palm-oil-in Roraima.

scholarly journals Fluktuasi Populasi Serangga Wereng Batang Coklat (Nilaparvata lugens) Pada Lahan Sawah Di Kabupaten Kerawang Jawa Barat

Agrologia ◽  
2018 ◽  
Vol 7 (2) ◽  
Author(s):  
Martua Suhunan Sianipar
Keyword(s):  
Regression Analysis ◽  
Natural Enemy ◽  
Diversity Index ◽  
Brown Planthopper ◽  
Nilaparvata Lugens ◽  
Population Fluctuation ◽  
Plant Pests ◽  
Nilaparvata Lugens Stål ◽  
Experimental Plots

Brown Planthopper (Nilaparvata lugens Stal.) is a main pest of paddy. The purpose of this research is to study the population of Brown Planthopper and the natural enemy. The method of this research using survey. Survey was conducted in three experimental plots at JatisariSubdistrict, Karawang District, West Javaand in the greenhouse of the Department of Plant Pests and Deseases, Faculty of Agriculture,  Universitas Padjadjaran. The sample were collected by systematically diagonal using yellow stiky trap and manually or visual counting. The result showed population fluctuation BPH below the economy line where is temperature, humidity and rainfall did not significantly effect to the BPH population. It was indicated by the regression analysis of each temperature Y= (- 24.225 + 1.008 X1 ; R2 =0,020; P/Sign = 0.660),  Humidity  (Y=- 32.337 + 0.424 X2; R2  = 0,124; P/ Sign  = 0.261) and Rainfall (Y=1.707 + 0.090 X3 ; R2  = 0.050; P/ Sign = 0.487). There is a relation between temperature, humidity and rainfall to BPH (Y = - 123 + 2.685 T + 0.649 RH - 0.14 CH; R2 = 0.236; P/ Sign = 0.516) dit not significantly because as the value of significance (P = Sign)  > 0.05.8. The diversity index was moderate 1.88

Seasonal effects of food provisioning on body fat, insulin, and corticosterone in free-living juvenile Belding's ground squirrels (Spermophilus beldingi)

2002 ◽  
Vol 80 (2) ◽  
pp. 366-371 ◽  
Author(s):  
Scott Nunes ◽  
Eva-Maria Muecke ◽  
Kay E Holekamp
Keyword(s):  
Body Fat ◽  
Plasma Insulin ◽  
Plasma Concentrations ◽  
Plasma Corticosterone ◽  
Ground Squirrels ◽  
Seasonal Effects ◽  
Free Living ◽  
Active Season ◽  
Extra Food ◽  
Spermophilus Beldingi

We evaluated the relationship between body fat and the metabolic hormones insulin and corticosterone in free-living juvenile Belding's ground squirrels (Spermophilus beldingi). Some free-living juveniles were provisioned with extra food high in fat and calories, and unprovisioned juveniles were used as controls. Body fat (as a percentage of body mass) of squirrels was regularly evaluated using non-invasive methods. Blood samples were also regularly collected from juveniles and assayed for plasma concentrations of insulin and corticosterone. Provisioned juveniles were fatter than unprovisioned juveniles during most of the active season, but differences in body fat disappeared near the end of summer as juveniles began fattening for hibernation. Thus, our data indicate that although body fat may fluctuate with energy availability early in the active season, it is regulated at precise levels as squirrels prepare for winter. Plasma corticosterone concentrations did not differ between provisioned and unprovisioned juveniles. However, plasma insulin concentrations were greater in provisioned than in unprovisioned juveniles early in the summer. Differences in insulin concentrations disappeared later in the active season, just prior to the disappearance of differences in body fat. Moreover, plasma insulin concentrations were significantly correlated with subsequent changes in body fat. Thus, our data suggest a link between insulin and seasonal regulation of body fat in juvenile S. beldingi.

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