Average Annual Population Growth Research Articles

An assessment of the medium-term reproductive success of an extralimital white rhinoceros population

The white rhinoceros (Ceratotherium simum) is threatened primarily due to continued poaching for its horns. In South Africa, partly to promote the conservation of the species, white rhinos have been introduced into areas where they did not occur historically (i.e. where they are considered extralimital). Few studies have investigated the conservation contribution of extralimital white rhinos to the overall national herd. We aimed to determine whether the white rhinos introduced to a private game reserve in the Eastern Cape province have been successful from a reproductive perspective. We calculated inter-calving intervals, age at first calving, sex ratios of calves, and recruitment rates for white rhinos at a single site between 1992 and 2019. The average net annual population growth rate for the population was 10%, which is higher than the recommended 5% by the Biodiversity Management Plan for white rhinos. Trends in density-dependent parameters such as age at first calving and inter-calving intervals also indicated that the study population is still well below the density at which ecological constraints may manifest. We demonstrate that an extralimital white rhino population in the Eastern Cape can be successful from a reproductive perspective.

Socio-Environmental Vulnerability of Water in the Estuary of the Metropolitan Region of Santos (Brazil)

Abstract Santos and São Vicente Estuarine Complex (SSEC) is a densely populated coastal area that houses the main port in Latin America and the most prominent Brazilian industrial complex. Irregular occupations in preservation areas result in a disorderly increase in population, with negative social and environmental impacts. We evaluated the average annual growth of 74 slums occurring in this area and variations in water quality from 2005 to 2018. We monitor the growth of the occupied areas and estimate their respective populations. The average annual population growth was over 6% per year (p.a.). Invasions of new areas and verticalisation of already occupied areas represent 85% of the growth seen. The monthly polluting loads exceeded 450 tonnes or 2,086,000 m3, compromising the waters and local and regional public health. We strongly recommend re-urbanising the area using the resource savings caused by water loss to reduce the risks of ecosystem degradation, damage to health and disease spread.

Evaluating otter reintroduction outcomes using genetic spatial capture-recapture modified for dendritic networks.

Monitoring the demographics and genetics of reintroduced populations is critical to evaluating reintroduction success, but species ecology and the landscapes that they inhabit often present challenges for accurate assessments. If suitable habitats are restricted to hierarchical dendritic networks, such as river systems, animal movements are typically constrained and may violate assumptions of methods commonly used to estimate demographic parameters. Using genetic detection data collected via fecal sampling at latrines, we demonstrate applicability of the spatial capture–recapture (SCR) network distance function for estimating the size and density of a recently reintroduced North American river otter (Lontra canadensis) population in the Upper Rio Grande River dendritic network in the southwestern United States, and we also evaluated the genetic outcomes of using a small founder group (n = 33 otters) for reintroduction. Estimated population density was 0.23–0.28 otter/km, or 1 otter/3.57–4.35 km, with weak evidence of density increasing with northerly latitude (β = 0.33). Estimated population size was 83–104 total otters in 359 km of riverine dendritic network, which corresponded to average annual exponential population growth of 1.12–1.15/year since reintroduction. Growth was ≥40% lower than most reintroduced river otter populations and strong evidence of a founder effect existed 8–10 years post‐reintroduction, including 13–21% genetic diversity loss, 84%–87% genetic effective population size decline, and rapid divergence from the source population (F ST accumulation = 0.06/generation). Consequently, genetic restoration via translocation of additional otters from other populations may be necessary to mitigate deleterious genetic effects in this small, isolated population. Combined with non‐invasive genetic sampling, the SCR network distance approach is likely widely applicable to demogenetic assessments of both reintroduced and established populations of multiple mustelid species that inhabit aquatic dendritic networks, many of which are regionally or globally imperiled and may warrant reintroduction or augmentation efforts.

Assessment of Grey Water Generation and Characteristics to Reduce Clean Water Resources Usage in Pekanbaru City

Pekanbaru city development in various sectors is growing rapidly in line with the population growth. The average annual population growth rate (2017-2020) is 2,64%. The consumption of clean water for each person is influenced by various factors such as: climate, population characteristics, socio-economy, and variety of activities. The volume of grey water (non-toilet liquid waste) generated ranges from 50% -80% of the total clean water used. The characteristics of grey water depend on the diversity of household uses of clean water. This study aims to assess the generation and characteristics of grey water in the city of Pekanbaru. Furthermore, it can be seen that critical flows that have the potential to be reused, such as for watering plants and rinsing / flushing toilets, will reduce the use of clean water sources. The method used is data collection (secondary and primary) and literature studies, assessing the characteristics of grey water by referring to the quality standards of domestic wastewater PERMEN LHK RI No. 68/2016, and conducted a system assessment using MFA-STAN. The grey water survey and sampling were carried out in six densely populated sub-districts (Tampan, Tenayan Raya, Marpoyan Damai, Bukitraya, Rumbai Pesisir, and Limapuluh). The results obtained, the generation of grey water in Pekanbaru city is 57,869,008.51 m3 / year. The characteristics of the grey water in Pekanbaru City (average value) are pH 7.42; BOD 44,21 mg / L; COD 118.99 mg / L; TSS 17 mg / L; Oil and Fat 6.67 mg / L; and Ammonia 6.09 mg / L. Grey water has the potential to be reused for sanitation sector and agricultural sector so that it can reduce the use of clean water by up to 50%.

Assessing the Role of Infiltration Galleries to Enhance Groundwater Recharge in Model Town Lahore

Lahore is the provincial capital of Punjab and second biggest city of Pakistan with respect to the population. Average annual population growth of Lahore is 4.14% from 1998-2018, which is much higher than the average population growth rate of Pakistan which is 2.4%. According to investigations average annual groundwater depletion rate of Lahore is 1.07 m/year. As with the growth of population new housing societies are being built to accommodate the burgeoning population. These societies enhance impermeable areas, moreover, pump huge amount of groundwater from the underground water source. There should be sustainability in water pumping and water recharging. Past studies show that groundwater exploitation in Lahore is not sustainable as abstraction rates are higher as compared to groundwater recharge rates. Therefore it is necessary of find out alternative means to recharge the groundwater aquifer of Lahore. There is a need to investigate the role of infiltration galleries to accelerate the groundwater recharge. In order to complete the research, temporal distribution was plotted on ArcMap. HEC-HMS was used for the calculation of discharges which were verified with analytical methods. Groundwater model prepared on Visual MODFLOW was calibrated and validated. The results indicate that due to groundwater overexploitation water levels continue to decrease with the passage of time. The average simulated water table decline is 1.1 meter per year in the study area. So in order to overcome this crisis, infiltration galleries were proposed and designed in the study area. It was seen that these infiltration galleries allow recharging the groundwater at better rate. As the model results showed that depletion rate of groundwater reduces and the groundwater level is about 0.3m higher when there are infiltration galleries. The study proposes that the Infiltration Galleries have a potential to recharge the groundwater at good rate, therefore its installation must be preferred according to the groundwater hydrological balance in the region.

Reconstruction of brown bear population dynamics in Slovenia in the period 1998-2019: a new approach combining genetics and long-term mortality data

Reliable data and methods for assessing changes in wildlife population size over time are necessary for management and conservation. For most species, assessing abundance is an expensive and labor-intensive task that is not affordable on a frequent basis. We present a novel approach to reconstructing brown bear population dynamics in Slovenia in the period 1998-2019, based on the combination of two CMR non-invasive genetic estimates (in 2007 and 2015) and long-term mortality records, to show how the latter can help the study of population dynamics in combination with point-in-time estimates. The spring (i.e. including newborn cubs) population size estimate was 383 (CI: 336-432) bears in 1998 and 971 (CI: 825-1161) bears in 2019. In this period, the average annual population growth rate was 4.5 %. The predicted population size differed by just 7 % from the non-invasive genetic size estimate after eight years, suggesting that the method is reliable. It can predict the evolution of the population size under different management scenarios and provide information on key parameters, e.g. background mortality and the sex- and age-structure of the population. Our approach can be used for several other wildlife species, but it requires reliable mortality data over time.

Demographic analysis reveals a population decline of the Longnose stingray Hypanus guttatus in Northeastern Brazil

High fishing pressure on elasmobranchs had caused declines in their populations worldwide, though these declines may not always be observed due to lack of monitoring. The Longnose stingray Hypanus guttatus is one of the most abundant and captured species in Northeast Brazil, mainly as bycatch by shrimp trawl. We aimed to estimate how the population of H. guttatus behaves in the face of different fishing pressures in the Northeast. For this purpose, we used a life matrix analysis from the metadata of three studies in the Northeast of Brazil (Bahia, Alagoas and Rio Grande do Norte). The average annual population growth rate estimated for the three states was strongly negative (−11.83%). However, there was considerable regional variation: data from Bahia showed in fact a low level of positive growth (3.24%) compared to the severe population decline (−29.47% per year) in Rio Grande do Norte, caused by the high mortality from shrimp trawling We conclude that the Longnose stingray has a high risk of long-term population decline in Northeastern Brazil, mainly caused by the high capture rate of juveniles.

Determining Optimal Stock Density of Punjab Urial (Ovis vignei punjabiensis) in Captivity for Breeding, Population Growth and Reintroduction Potential.

The Punjab urial (Ovis vignei punjabiensis) is an endangered wild sheep of Pakistan, raised in captivity with the aim of re-introduction. To date, no information is available about population trends of this species in captivity. The current study was conducted with the aim to evaluate the population trend to better guide captive breeding for improved productivity and conservation value. Annual population data recorded and maintained by the Wildlife Department Khyber Pakhtunkhwa, Pakistan, were used. The data were compiled and analyzed in Microsoft Excel 2010 for determining growth rates and package Growthcurver in R-version 3.5.1 was used to produce a graphical representation of the population trend. The overall average annual population growth rate was rN = 0.22. Results revealed a fast initial growth rate with an average value of rN = 0.4 per year. Birth rates of bN = 0.45 for the first nine years were considerably higher than the death rates dN = 0.22 and the population increased with exponential growth. In the subsequent year, very high mortalities rates (dN = 1.2), likely attributed to the clumping of the population, resulted in the collapse of the population, leaving it in a state of unstable equilibrium. Results support the evaluation of management data to reveal carrying capacity in captive populations, to guide and inform appropriate release of surplus animals into natural habitats.

Analyzing spatiotemporal types and patterns of urban growth in watersheds that flow into Jakarta Bay, Indonesia

Jakarta is the economic hub of Indonesia and the primary target for urbanization. This condition encourages urban growth, particularly in the peri-urban regions of Jakarta. Uncontrolled urban growth impacts Jakarta negatively, because of its location downslope of eight watersheds. This study evaluated the spatiotemporal characteristics and types of urban growth in the watersheds that flow into Jakarta Bay using remote sensing data. Spatial rules revealed three urban growth types, including infilling, edge expansion, and outlying, from 2001 to 2017. Spatial metrics provided quantitative data on urban growth characteristics and explained the spatiotemporal dynamics of urban growth. The study area was divided into eight cardinal directions to analyze urban growth trends. From 2001 to 2017, the average annual urban and population growth rates were 3.75% and 3.9%, respectively. The prominent urban growth types, edge expansion and infilling, coalesced urban patches and rendered urban areas more compact. Results indicated that the North-West (NW) region demonstrated the most orderly urban growth, whereas the East region demonstrated the least.

Current distribution, abundance, and breeding biology of White Terns (Gygis alba) on Oahu, Hawaii

White terns (Gygis alba) are common on many islands in the tropical and subtropical Pacific, Atlantic, and Indian oceans, but in the southeastern Hawaiian Islands they are found only on Oahu, where they are listed as threatened by the State of Hawaii. In 2016, we censused the White Tern population on Oahu, mapped their distribution, and investigated their breeding biology. The total White Tern population on Oahu was 2,308 birds, including 1,408 breeders and ∼900 nonbreeders. The number of White Terns on Oahu has increased 282% since the previous census in 2002, for an average annual population growth rate of 7.7%. We observed White Terns only in urban and suburban areas of Honolulu and not in other parts of the island. Breeding occurred year-round, with 2 peaks in egg-laying in March and October. Hatching success was 69%, fledging success was 83%, and overall breeding success was 57%. Pairs made an average of 1.75 (SE 0.09) breeding attempts per year and produced an average of 1.08 (0.09) offspring per year (range 0–3). Terns used >58 tree species for breeding and roosting, most of which were large (>45 cm diameter). Average height in trees of breeding attempts was 9.1 (0.2) m. White Terns are thriving in urban Honolulu and are not seriously affected by numerous potential sources of human disturbance or predation from nonnative mammals, but some efforts will help to ensure their status remains secure. Received 7 July 2017. Accepted 6 January 2018.

109 REPRODUCTIVE PERFORMANCE PARAMETERS IN A LARGE HERD OF CONFINED FREE-ROAMING WHITE RHINOCEROSES (CERATOTHERIUM SIMUM)

During the last decade, the population of wild white rhinoceroses has been in steady decline, mainly because of increased poaching incidents and habitat loss. Therefore, more data are necessary on reproduction of this endangered species in order to improve captive breeding, which is at present not very successful. Currently, ~20,000 Southern white rhinoceroses are remaining of which the majority are privately owned. The aim of this study was to create reference values of several reproductive parameters for future white rhinoceros breeding. In previous studies, only low numbers of animals have been observed, often in captive settings. In this study performed between 2008 and 2016, reproductive performance was analysed in 1300 animals kept in a geographically identical, confined free-roaming environment. Analyses were performed in R (R Development Core Team, 2008) using the lme4 and fixed package to model the number of animals born (family = Poisson) and sex ratio (family = binomial). Females had a median age of 83.2 months at first calving (interquartile range: 72.9–110.7) and intercalving intervals of 29.2 (interquartile range: 24.6–34.8) months. Fertility records were excellent with 38% adult females calving per year when compared to previous research, in which first reproduction occurred between 78 and 138 months of age with an intercalving period of 3 years average. A clear seasonal calving pattern was seen with a significant increase of calvings during December–April when compared to April–December. In contrast to the Trivers-Willard hypothesis, our results did not show any significant skewed progeny sex ratios. Weather observations showed no significant influence of rain or season on sex ratios of the calves. Furthermore, translocations of animals did not seem to interfere with reproductive success when looking at intercalving periods or age at first calving. In the free roaming environment of over 10,000 ha, this captive population showed an average annual population growth (%) of 18 ± 0.07 (minimum 5 to maximum 26). As such, comparable breeding management systems can increase population numbers and contribute to increase dwindling population numbers of the wild white rhinoceros. This is the first study to describe reproductive performances in the white rhinoceros at such large scale, indicating that confined free-roaming populations can be used for captive breeding of white rhinoceros to contribute to white rhinoceros conservation.

El ocio, tiempo libre y calidad de vida para un envejecimiento activo, el caso de la Universidad de Burgos

Con este trabajo de investigación pretendemos encontrar las relaciones existentes entre el ocio, el tiempo libre y la percepción de calidad de vida por parte de los alumnos asistentes a nuestro programa educativo de personas mayores para el logro de un envejecimiento activo de calidad. Estamos en la actualidad ante un gran reto, el logro del bienestar para todos y una sociedad inclusiva hacia todos los colectivos que la integran. Como podemos confirmar en el Informe del Imserso publicado en 2008 para el 2010 un 17.2 % del total de la población se encontraba en una edad de 65 o más años. La tasa de crecimiento de la población mayor se encuentra 1.26 % superior al crecimiento medio anual de la población global de España por lo que podemos ver ese cambio en la tendencia demográfica que además nos asegura como la edad mediana de la población española se situaba en el año 2000 en 38.8 años. La proyección de edad media para el año 2050 se situará en 49.5 años posicionándonos para ese año por encima de la edad media europea. Con esta investigación describiremos en qué manera nuestro Programa Educativo para Personas Mayores contribuye al envejecimiento activo catalogando datos relativos al Ocio, al Tiempo Libre y la Calidad de Vida. En el trabajo también compararemos los datos obtenidos por sexos y tramos de edad para poder compararlos con otras estadísticas oficiales publicadas hasta ahora tanto a nivel estatal como internacional.

Saudi Arabia: Oil for Water

In 2014, the Kingdom of Saudi Arabia faced a freshwater shortage. Despite the global financial crisis, Saudi Arabia experienced modest economic expansion and increasing stress on its water infrastructure due to expanding agricultural production. The major investments in desalinization plants that the country expected to see had not yet materialized, furthering the strain on resources. This case, used in Darden's Economics of elective, examines what policy reforms should be explored in bringing Saudi Arabia's water use and agricultural production into balance. Excerpt UVA-GEM-0129 Rev. May 29, 2015 Saudi Arabia: Oil for Water Saudi Arabia was facing a chronic water crisis. A desert country in the Middle East with virtually no permanent rivers or lakes and an average of 59 millimeters (mm) of rain annually, Saudi Arabia was in terms of natural renewable water resources one of the poorest countries in the world. To quell its thirst for water, the kingdom was banking on a vast and growing desalination infrastructure. It was, however, an open question whether building more desalination plants would suffice. According to many experts, Saudi Arabia had tough policy choices to make. International investors were following the situation closely, albeit with some skepticism, especially in the aftermath of the Arab Spring. In the words of Global Water Intelligence (GWI), a water expert group from the United Kingdom: “Saudi Arabia is in many ways a very mature market for water and wastewater services—in particular for desalination. In other ways, there is a huge amount of development still to be done…What remains to be seen is whether the opportunities for investors and operators will develop as much as hoped for.” The Saudi Society and Economy The Kingdom of Saudi Arabia was the largest country in the Arabian Peninsula, roughly one-quarter the size of the United States. It bordered Egypt, Jordan, Iraq, Kuwait, the United Emirates, Yemen, and Oman (see Exhibit 1). Founded in 1932 after a long struggle to unite local tribes, Saudi Arabia had experienced dramatic changes, especially since the 1960s. It had become a well-off nation whose per capita income in 2013—the equivalent of $ 25,000—was comparable to that of the European Union average (see Exhibit 2). Reflecting its climb up the income ladder, life expectancy had steadily increased from barely more than 50 years in 1960 to around 75 in 2013; child mortality had also dropped significantly. Saudi Arabia was a country of young people; its median age was 25 years. Its population had increased about seven times since the 1960s and reached 30 million in 2013, which amounted to an average annual population growth rate of around 3.4%. Driving this rapid growth was, on one hand, the high fertility rate (seven children per woman in 2006, and still three per woman in 2011) and, on the other hand, immigration. Saudi Arabia had been a magnet for citizens from other countries: in 2013, no less than 32% of its population was non-Saudi. . . .

Demograficzne uwarunkowania rozwoju miasta Poznania

W niniejszym artykule przedstawiono dotychczasowe i przyszłe trendy rozwoju populacji miasta Poznania. Celem badań jest wskazanie powiązań i relacji między rozwojem demograficznym miasta i otaczających je obszarów podmiejskich w zakresie starzenia się ludności, rynku pracy i poziomu wykształcenia.Zmniejszenie średniego rocznego tempa wzrostu liczby ludności w powiecie poznańskim oraz towarzyszący mu spadek liczby mieszkańców Poznania wskazują na fazę absolutnej dezurbanizacji w rozwoju miasta. Trudno jest określić wpływ nieco większego wzrostu płodności kobiet w Poznaniu, w porównaniu z obserwowanym w otaczającym miasto regionie. Z kolei zmiany w długości oczekiwanego trwania życia wskazują rosnące podobieństwa charakterystyk rozwoju demograficznego miasta i strefy podmiejskiej.Procesy demograficzne są analizowane w powiązaniu ze zmianami społecznymi. Tempo wzrostu liczby absolwentów wyższych uczelni w najbliższym otoczeniu Poznania jest znacznie wyższe aniżeli obserwowane w centrum miasta. Zwrócono także uwagę na wpływ wykształcenia na rozwój kariery i wydłużenie okresu aktywności zawodowej, a także na decyzje matrymonialne i prokreacyjne. Wzrost poziomu wykształcenia siły roboczej ma stały, pozytywny i znaczący wpływ na wzrost gospodarczy.

Fertility rates in Tesanj municipality (Bosnia and Herzegovina) in the second half of the 20th and the beginning of 21st century

In the second half of the 20th century, demographic changes of the Tešanj municipality developed in accordance with the complex socioeconomic circumstances in this area. In the period from 1953 to 1991 the population of Tešanj municipality increased by the average annual population growth rate of 1.5%. The biggest impact on demographic trends had the positive and relatively high rates of natural increase. The natural population change of Tešanj municipality in this period was the result of the effect of biological, socioeconomic, psychological and other factors. In this period fertility significantly influenced the rates of natural increase of municipal population. The gradual decline process of the fertility rates, which has started in the 1960s and still lasts, reflected on the natural population change and population growth rates of Tešanj population. Additional decrease of the fertility and birth rates, as well as moderate increase of mortality rate was observed. This occurred due to the decrease of the total population, as well as the adverse socioeconomic circumstances after 1995, which resulted in low natural growth rates.

Bhaktapur, Nepal: the MAL-ED birth cohort study in Nepal.

The Etiology, Risk Factors and Interactions of Enteric Infections and Malnutrition and the Consequences for Child Health and Development (MAL-ED) cohort study site in Nepal is located in the Bhaktapur municipality, 15 km east of Kathmandu, the capital city of Nepal. Bhaktapur, an ancient city famous for its traditional temples and buildings, is included on UNESCO's World Heritage List and is a major tourist attraction in Nepal. Nepal is a land-locked country located in South Asia between China and India with an area of 147 181 km(2), ranging from sea-level plains to Mount Everest, the world's highest peak. The total population as of the 2011 census was 26.6 million, with an average annual population growth rate of 1.4. Nepal is one of the world's least developed countries and is ranked 157 of 186 in the 2013 Human Development Report; one-third of the Nepali population lives below the poverty line. The current under-5 mortality rate is 54 per 1000 live births, the infant mortality rate is 46 per 1000 live births, and the neonatal mortality rate is 33 per 1000 live births. Vaccine coverage for all Expanded Program on Immunization vaccines is >80%. Among children, the most common diseases contributing to significant morbidity and mortality are acute respiratory infection and dehydration from severe diarrhea. In this article, we report on the geographic, demographic, and socioeconomic features of the Bhaktapur MAL-ED site and describe the data that informed our cohort recruitment strategy.

Leisure, recreation and quality of life for active aging, University of Burgos case

With this research we try to find the relationship between the entertainment, leisure and perceived quality of life by students attending our education program for older people achieving aging asset quality. We are at present a major challenge to the achievement of welfare all inclusive society and to all groups within it. As we can confirm in the report published in 2008 by IMSERSO in 2010 17.2% of total the population was at an age of 65 years. The growth rate of the population is 1.26% higher than the average annual population growth. Overall, in Spain we can see this change in the demographic trend, it also assures us as the median age of the Spanish settlement established in the year 2000 to 38.8 years. The projected median age in 2050 will stand at 49.5 years positioning ourselves for that year above the European Middle Ages. with this describe how research in our Educational Program for People Major contributing to active aging cataloging data on Leisure, the Leisure and the Quality of Life. The work will also compare the data obtained by sex and age to compare them with other statistics official published so far at both state and international level.

Trends in Annual Survival of Steller’s Eiders Molting at Izembek Lagoon on the Alaska Peninsula, 1993–2006

Izembek Lagoon, located on the Alaska Peninsula, is an important molting area for the Pacific population of Steller’s Eiders (Polysticta stelleri) and was the site of consistent banding effort during 1993–2006. We used Pradel mark-recapture models to estimate annual survival and population growth rates for adult Steller’s Eiders molting at Izembek Lagoon. We designed 32 models that included effects of sex and year on survival, recapture rate, and seniority, as well as potential trends in survival and seniority. The top model incorporated a two-phase trend (1993–98, 1999–2003) in survival and seniority for each sex and fully sex- and year-specific recapture rates. Average annual adult survival was estimated at 0.86 (SE = 0.030) for females and 0.87 (SE = 0.018) for males. Average annual population growth rates since 1998 were estimated to be approximately 1.0 for both sexes. A brief warming event in the Pacific Decadal Oscillation (1997–98) coincided with the lowest estimates of annual survival, while a subsequent return to cooler conditions in the Bering Sea coincided with the highest estimates and an increasing trend in annual survival.

Perfil demográfico dos índios Boróro de Mato Grosso, Brasil, 1993-1996

This paper analyzes the demographic profile of the Boróro Indians from Mato Grosso State, Brazil, from 1993 to 1996. Data came from annual collection and registration of vital statistics conducted by the health service in three villages (Garças, Meruri, and Morada dos Boróro). The average annual population growth rate was 2.4%. Nearly half (44%) of the population was younger than 15 years (median 16 years). The crude birth rate was 30.9 per 1,000 and the crude death rate 7.3 per 1,000 inhabitants. The infant mortality rate was high (58.8 per thousand live births), probably resulting from precarious health conditions in the villages. The results showed that women married younger than men and that there were numerous unmarried adult men (26.7%) and women (13.3%), as compared to data from other indigenous groups. The total fertility rate of Boróro women was 4.3, quite low compared to other indigenous communities in Brazil. The study emphasizes the importance of systematically collecting and analyzing demographic data on indigenous populations.

Estimating the quantity of solid waste generation in Oyo, Nigeria

The study established waste multipliers that could be used in conjunction with the population figure of a city to estimate the quantity of solid waste generation in the developing world. Oyo, a traditional city in Nigeria was the focus of the study. Two sets of data were collected. The first was the information on the socio-economic attributes of residents obtained from 648 households through questionnaires administered using a systematic random sampling technique. The second was the measurement of waste generated in 25% of the households for a week in each of the 12 months of the year. The study established that 23.3% of the residents surveyed have educational qualifications beyond secondary school, with 51.2% engaged in occupations requiring very little or no formal education and 50.9% were in the low-income group. The daily per capita solid waste generation was 0.129 kg. The highest (9.8%) and lowest (6.5%) of the annual quantities of waste were produced in October and February, respectively. Similarly, 20.2% of the weekly generation was produced on Saturday and the 10.2% produced on Thursday was the lowest. Animal dung, which accounted for 18.0%, constituted the highest component of the total solid waste generated. The study further established that the organic component of the waste generation was 75.4%. The results of the regression analysis R2 significant at 0.001 showed that income, household size, social status, occupation, education and season of the year explained 88.8% of waste generation in Oyo. It was established that 50.90 tonnes of solid waste was generated per day in the city in 2005, and the daily generation in the year 2008 is estimated to be 55.20 tonnes. The study concluded that with an average annual population growth of 13 000 people for the town, an additional 1.3 acres of land will need to be legally acquired annually, implying that 10.92-19.68 hectares ill be required as dump site(s) over the next 20-30 years.