Public Opinions about Causes of Declining Fertility in Developing Countries

Research indicates multiple causes of declining total fertility rate (TFR) in developing countries, including reduced child mortality, improved education and economy, family planning programmes and female empowerment. However, public opinions about the causes have rarely been studied. Using surveys in 2022 in Sweden and Nigeria, we compare answers of educated citizens to the question of why fertility (birth rate) has fallen in developing countries (also in Nigeria). In Sweden, 72 per cent of respondents suggested improved living conditions, including economy and education, lower infant mortality and generally progressive development. In contrast, in Nigeria 66 per cent of the respondents suggested that poverty, bad socioeconomic conditions and poor health cause declining birth rates. Birth rates were thus assumed to be falling mainly because the conditions in Nigeria are generally getting worse, not better. A contributing reason for the difference of opinions between the countries may be social norms for large families in Nigeria. Few Swedish respondents suggested family planning (1.9% of answers) but this answer was more common in Nigeria (5.9%). In Sweden, women answered contraceptive use (17%) more often than did men (4.5%), while in Nigeria the contraception answer hardly differed between men (6.1%) and women (5.7%). Only minor differences in opinion existed between the southern and northern (Muslim-dominated) states in Nigeria, among educated respondents that participated in this survey. We recommend more, and extended surveys

potential environmental impacts of EU immigration policy: future population numbers, greenhouse gas emissions and biodiversity preservation

This article clarifies the potential environmental impacts of more or less expansive EU immigration policies. First, we project the demographic impacts of different immigration policy scenarios on future population numbers, finding that relatively small annual differences in immigration levels lead to large differences in future population numbers, both nationally and region-wide. Second, we analyze the potential impacts of future population numbers on two key environmental goals: reducing the EU’s greenhouse gas emissions and preserving its biodiversity. We find that in both cases, smaller populations make success in these endeavors more likely – though only in conjunction with comprehensive policy changes which lock in the environmental benefits of smaller populations. Reducing immigration in order to stabilize or reduce populations thus can help EU nations create ecologically sustainable societies, while increasing immigration will tend to move them further away from this goal

Aging human populations: good for us, good for the Earth

As the nations of the world grapple with the task of creating sustainable societies, ending and in some cases reversing population growth will be necessary to succeed. Yet stable or declining populations are typically reported in the media as a problem, or even a crisis, due to demographic aging. This is misguided, as economic analyses show that the costs connected with aging societies are manageable, while the economic, social, and environmental benefits of smaller populations are substantial. Earth's human-carrying capacity has been exceeded; hence, population growth must end and aging societies are unavoidable. They should be embraced as part of a just and prosperous future for people and the other species with whom we share our planet

Jordlöpare på fyra ljunghedar i Halland: Studier av successionsstadier och förslag till miljöövervakning

I brittiska studier har rapporterats att ljunghedar är värdefulla för den lägre faunan (jordlöpare och spindlar studerades). För att klargöra om detta gäller även svenska ljunghedar studerades juni-augusti 1993 särskilt jordlöpare på fyra ljunghedar i Halland (Figur 1), två större hedar (Mästocka och Sandsjöbacka) och två mindre (Bållaltsbygget och Hållsundsudde). På de större hedarna studerades ljungytor och nyligen brända ytor; på de mindre fanns endast (äldre) ljung. På varje hed samlades djur in med hjälp av totalt 20 fallfällor, fördelade på två ytor á 100x100 m. Totalt påträffades 62 arter av jordlöpare, vilket motsvarar cirka 18% av de svenska arterna. Liksom i Storbritannien är ljunghedarna i Sverige uppenbarligen viktiga för denna skalbaggsfamilj. De båda större hedarna var artrikare än de två mindre, delvis beroende på ytan, men även på förekomst av bränning och bete (ytor av äldre ljung bör dock få finnas kvar). Mästocka framstår som särskilt värdefull, men på Sandsjöbacka påträffades bland annat en sällsynt, rödlistad art. En beräkning av likhet i artsammansättning (Sørensens index) på hedarna visar att de på olika sätt kompletterar varandra vad gäller jordlöparfaunan. Rapporten avslutas med förslag och synpunkter på miljöövervakning av ljunghedar. Jordlöpare kan vara en lämplig grupp för övervakning, eftersom gruppen (1) hyser många olika arter, (2) är relativt väl känd ekologiskt, och (3) är en värdefull faunakomponent på ljunghedar. Övervakningen bör baseras på lokaler (ca 10-15) som statistiska enheter, även om Mästocka är värd särskild uppföljning.Regionala inventeringsrapporter import från MDP 2015-05</p

Evaluating partial cutting in broadleaved temperate forest under strong experimental control: Short-term effects on herbaceous plants

Partial harvesting of forest for biofuel and other products may be less harmful to biodiversity than clear-cutting, and may even be beneficial for some species or groups of organisms such as herbs. There are, however, few well-controlled experiments evaluating positive and negative effects, such as species losses directly after harvest. In closed canopy mixed oak forest in Sweden, about 25% of the tree basal area and 50-90% of the understory was removed (mainly spruce, birch, aspen, lime, rowan and hazel). In each of six forests, we studied herbs in an experimental (cutting) plot and a control plot (undisturbed) before, and in the first summer, after the harvest (conducted in winter). Losses of species were similar in experimental and control plots (15-16%). The harvest increased species richness by 4-31% (mean 18%); also species diversity (H) increased. Several ruderals increased in experimental plots, but most changes occurred in grassland and forest species; partial cutting led to complex, partly unpredictable early changes in the herb community. A review of early effects of partial cutting (eight experiments) indicated that it increases herb species richness in stands of broadleaves, but apparently not in conifer stands; there was no evidence that partial cutting increases species losses. Thus, with respect to early changes after harvest, we found no negative effects of partial cutting on herbs. We suggest, however, that some proportion of closed-canopy mixed oak forest should not be harvested, to protect rare, potentially sensitive herbs, and to create stand diversity. (c) 2005 Elsevier B.V. All rights reserved

The economy of selective cutting in recent mixed stands during restoration of temperate deciduous forest

Forest cover is increasing in many regions due to spontaneous reforestation on abandoned pastures and fields. The resulting recent forests may need management to improve ecosystem quality, and this could possibly be combined with timber production in specific cases. Temperate deciduous (TD) trees have declined steeply during the past millennium, but some now increase in the recent forests, often mixed with Norway spruce. Removing spruce may benefit these trees and for example oak regeneration, flowering plants and pollination. The total area of forest suitable for restoration in Norway and Sweden is >100,000 ha. We evaluate the cost of selective cutting based on 26 field trials, 13 in each country, and sales from the initial cutting on average just barely compensate for the costs. By resurveying plots from a parallel project in Sweden, we found that about half of the cut volume had regrown after 16 years, and a second thinning may be needed in the near future. Coarse woody debris (CWD) had increased by 78%, indicating increasingly natural conditions. We conclude that selective cutting in recent forests may be part of a strategy to reach restoration and sustainability goals, but that long-term incentives for landowners need to be developed.publishedVersio

Did forest fires maintain mixed oak forests in southern Scandinavia? A dendrochronological speculation

In northern Europe, a long history of human exploitation effectively eliminated legacies of natural disturbances in mixed oak forests and we currently lack understanding of the role of natural disturbance factors in affecting oak regeneration into the forest canopies. We compiled dendrochronological, observational and paleochronological data from Southern Sweden to discuss the role of forest fires in oak (Quercus spp.) dynamics. We analyzed oak age structure and its growth dynamics in six southern Swedish forests, which experienced fires between 42 and 158 years prior to our sampling. Extending our analysis over longer time frames, we studied the relationship between sediment charcoal and oak pollen in an area of south-eastern Sweden, where oak has been a common canopy species. In three of the study sites, forest fires resulted in increased oak regeneration. Although fires were generally not associated with a wave of growth releases in surviving trees, the mean basal area growth rate of oaks increased by a range of 108% to 176%, following the fires. The overall pattern indicated that historical fires in oak-dominated forests were of low severity, did not kill canopy oaks, and yet provided a window of regeneration opportunities for that species. Post-fire sprouting of oak and an increase in oak seedling densities following modern prescribed fires are consistent with this explanation. Consistent with this conclusion were significant positive correlations between charcoal concentration and the oak pollen percentage in a site in southeastern Sweden. We discuss the co-occurrence of oak and pine in the historical southern Swedish landscape, as a possible analogy to eastern North American oak-pine forests. Modern conservation policies aimed at the preservation of oak in the southern Swedish landscape should consider the use of low severity fires to maintain natural oak regeneration

Conservation thinning in secondary forest: negative but mild effect on land molluscs in closed-canopy mixed oak forest in Sweden.

Secondary succession is changing the character of many temperate forests and often leads to closed-canopy stands. In such forests set aside for conservation, habitat management alternatives need to be tested experimentally, but this is rarely done. The Swedish Oak Project compares two often debated alternatives: minimal intervention and non-traditional active management (conservation thinning) on plots of each type replicated at 25 sites. We study responses of several taxa, and here report results for land molluscs. They are considered to be sensitive to more open, drier forest and we predicted a negative effect of the thinning (26% reduction of the basal area; mean value for 25 experimental forests). We sampled molluscs in the litter in ten 20 x 25 cm subplots, and by standardised visual search, in each plot. In total, we recorded 53 species of snails and slugs (24 369 individuals) and the mean species richness in plots was 17. Two seasons after thinning, mean (± SE) species richness had decreased by 1.4 (± 0.9) species in thinning plots, but increased by 0.7 (± 1.0) species in minimal intervention plots, a significant but small change with considerable variation among sites. In matched comparisons with minimal intervention, thinning reduced the overall abundance of molluscs. Most species responded negatively to thinning - but only five of the 53 species were significantly affected, and reproduction seemed to be negatively affected in only one species. An ordination analysis did not reveal any particular change in the species community due to thinning. Thus, the negative effect of conservation thinning on land molluscs was apparently mild - one reason was that many trees, shrubs and other forest structures remained after the treatment. Conservation thinning may be recommended, since other taxa are favoured, but minimal intervention is also a useful form of management for molluscs and saproxylic taxa