Experimental reintroduction of three grassland forbs to assess climate-adjusted provenancing, grazing protection and weed control

2018 ◽  
Vol 66 (8) ◽  
pp. 628
Author(s):  
S. McIntyre ◽  
A. O. Nicholls ◽  
P. Graff ◽  
J. Stol
Keyword(s):  
Livestock Grazing ◽  
Low Fertility ◽  
Population Increase ◽  
Growing Seasons ◽  
Realistic Option ◽  
Native Grassland ◽  
Eucalypt Woodlands ◽  
History Of ◽  
Source Populations ◽  
Early Performance

We explored climate-adjusted provenancing as a strategy for reintroduction of three perennial forbs: Microseris walteri, Bulbine bulbosa and Stackhousia monogyna into native grassland with a history of livestock grazing. Seed source populations were sampled over a temperature gradient of 2°C, located up to 120km from the receiving site. Two receiving-site management treatments were applied: hand removal of exotic species, and exclusion of macropod grazing and trampling. There were no effects of weeding the receiving grassland and we concluded the low fertility of the site provided protection from exotic competition. After eight growing seasons, protection from grazing resulted in double to triple the numbers of established plants, depending on the species. Amongst populations within a species, larger seeds and early emergence reflected later establishment success for Bulbine only. At the species level, early performance was not indicative of later numbers of reproductive plants established. We found no long-term evidence of home-site advantage in any species, and no apparent disadvantage of non-matching lithology. All source populations were represented at the end of the experiment (Season 6). Counts after eight seasons’ growth indicated a continuing trend of population increase in all three species. The persistence of all populations suggests that admixture or climate-adjusted provenancing may be a realistic option to restore depleted populations of herbaceous plants in grassy eucalypt woodlands in a warming climate.

scholarly journals A Revised Late Holocene Culture History for Moloka'i Island, Hawai'i

Radiocarbon ◽  
2007 ◽  
Vol 49 (3) ◽  
pp. 1273-1322 ◽  
Author(s):  
Mark D McCoy
Keyword(s):  
Initial Period ◽  
Oral Traditions ◽  
Population Increase ◽  
Radiocarbon Age ◽  
Subsistence Economies ◽  
Culture History ◽  
The Social ◽  
Social Landscape ◽  
Strong Material ◽  
History Of

Building directly upon a previous summary of 45 dates (Weisler 1989), this paper presents radiocarbon age determinations for 175 samples from archaeological and natural contexts and a revised culture history of Moloka'i Island, Hawai'i (cal AD 800 and 1795). Significant culture historical trends include an early settlement pattern apparently generalized with respect to ecozone; a remarkably long initial period of marine and endemic bird exploitation; strong material evidence for the concurrent intensification of subsistence economies, population increase, and the structuring of the social landscape through ritual; and links between island politics as described in oral traditions and site construction. Moreover, these results support a late chronology for the colonization of Hawai'i and demonstrate the value of spatial technology for building large chronometric databases.

scholarly journals The Influence of Biochar, Slow-Release Molasses, and an Organic N:P:K Fertilizer on Transplant Survival of Pyrus communis ‘Williams’ Bon Chrétien’

2016 ◽  
Vol 42 (2) ◽  
Author(s):  
Emma Schaffert ◽  
Glynn Percival
Keyword(s):  
Slow Release ◽  
Soil Amendments ◽  
Pyrus Communis ◽  
Low Fertility ◽  
Economic Losses ◽  
Soil Conditions ◽  
Urban Landscapes ◽  
Transplant Survival ◽  
Positive Effects ◽  
Growing Seasons

High mortality rates result from transplanting bare-rooted plants into urban landscapes where unsuitable soil conditions, such as low fertility and poor structure, often exist. Coupled with little aftercare, these losses can cause high economic losses to the industry. Previous studies have shown lowered transplant stress and higher survival rates through the addition of soil amendments at the time of planting to improve soil conditions. The efficacy of three soil amendments applied singly and in combination—biochar, slow-release molasses, and an organic N:P:K fertilizer—were investigated for their potential to reduce transplant losses of Pyrus communis ‘Williams’ Bon Chrétien. Results of this investigation showed that use of these soil amendments in virtually all cases had significant positive effects on tree growth and vitality across two growing seasons. For example, all amendments reduced mortality of Pyrus communis ‘Williams’ Bon Chrétien’ by 20% compared to none in treated controls, while increases in fruit yield and crown canopy coverage per tree ranged from 19.3% to 46.7% and 14.4% to 31.1% over non-amended soils when averaged over two growing seasons. Amendments of biochar with an organic N:P:K fertilizer and an organic N:P:K fertilizer alone showed, on average, the highest improvements in vitality and growth. Results indicate use of biochar, slow-release molasses, and organic N:P:K fertilizer amendments offer potential for increasing bare-root transplant survival and establishment of Pyrus communis ‘Williams’ Bon Chrétien.

scholarly journals When and how? Freshwater mussel recolonization in Lake Orta

2016 ◽  
Vol 75 (s2) ◽  
Author(s):  
Nicoletta Riccardi ◽  
Elsa Froufe ◽  
Manuel Lopes-Lima ◽  
Claudio Mazzoli
Keyword(s):  
Sediment Quality ◽  
Freshwater Mussel ◽  
Trophic Chain ◽  
Older Individuals ◽  
Host Fish ◽  
History Of ◽  
Water And Sediment Quality ◽  
Source Populations ◽  
Term Monitoring

Thanks to a video posted on a social network, live mussels of <em>Unio elongatulus</em>, have been recorded from Lake Orta (Italy) over one century after the last (and only) report. With its long and well documented history of pollution, Lake Orta offers the opportunity to document the post-extirpation recovery of freshwater unionid mussels. This case evidences that recovery/recolonization is possible despite a high devastation in the past, and permits to evaluate how fast recolonization may occur, in which way, and in what conditions.  The answer to the '<em>how</em> <em>fast</em>' was sought by estimating the age of the larger and seemingly older individuals of the population. To address the '<em>in which way</em>' we compared the haplotypes of Lake Orta specimens of <em>Unio elongatulus</em> (the only species present) with those of surrounding populations. We concluded that, since Lake Orta lacks a direct connection with the putative source populations, colonizing mussels were almost certainly transported by fish carrying glochidia that were used for lake restocking after liming. Data from the long-term monitoring of water chemistry and sediments have allowed defining what conditions proved to be suitable for survival making possible the start of mussels recovery. But not only water and sediment quality matters for mussels recovery, which was delayed by nearly ten years after the reappearance of fish. This delay reflects the need of the whole trophic chain to be reestablished to allow the survival of the suitable and healthy host-fish populations necessary for mussels reproduction.

scholarly journals The History of Elk (Cervus canadensis) Restoration in Ontario

2016 ◽  
Vol 130 (2) ◽  
pp. 167 ◽  
Author(s):  
Josef Hamr ◽  
Frank F Mallory ◽  
Ivan Filion
Keyword(s):  
Population Increase ◽  
Limiting Factor ◽  
Population Census ◽  
North Shore ◽  
Founding Population ◽  
Cervus Canadensis ◽  
History Of ◽  
Woods Lake ◽  
French River ◽  
Restoration Effort

Elk (Cervus canadensis) historically inhabited southern Quebec and central Ontario, but, by the early 1900s, the species was extirpated from this region. Attempts to re-establish an Elk population in Ontario during the first half of the 20th century had limited success. We reviewed historical documents, population census records, and a previous study pertaining to Elk reintroduced to Ontario in the early 1900s for clues to the cause(s) of their limited population growth. After an apparent rapid population increase in the 1940s followed by unregulated hunting during the subsequent 3 decades, Elk abundance in Ontario had not appreciably changed from 1970 to 1997, most likely because of the small founding population, unsustainable hunting, and accidental mortality. After the abolition of legal hunting in 1980, natural mortality appeared to be the main limiting factor. A limited sample of pregnancy and calf recruitment rates, body measurements, and physical condition parameters collected in 1993–1997, suggested that adults were healthy, reproducing successfully, and not limited by food availability; thus, it was concluded that remnant Elk populations could be augmented by introducing additional animals. A renewed Elk restoration effort, conducted from 1998 to 2001, imported 443 Elk from Elk Island national Park in Alberta to 4 release areas across central Ontario (Lake of the Woods, Lake Huron North Shore, Nipissing/French River, and Bancroft/North Hastings), resulting in a provincial population of about 800 Elk by 2013.

scholarly journals China’s Population Policy at the Crossroads: Social Impacts and Prospects

2013 ◽  
Vol 41 (2) ◽  
pp. 193-218 ◽  
Author(s):  
Quanbao Jiang ◽  
Quanbao Jiang ◽  
Shuzhuo Li ◽  
Quanbao Jiang ◽  
Shuzhuo Li ◽  
...  
Keyword(s):  
Ethical Issues ◽  
Population Policy ◽  
Labour Force ◽  
Fertility Rate ◽  
Low Fertility ◽  
Replacement Level ◽  
Counter Measures ◽  
History Of ◽  
Biased Sex Ratio ◽  
Three Stages

Abstract China’s total fertility rate fell below replacement level in the 1990s. From the 1970s the fertility rate declined dramatically, mainly as a consequence of the national population policy whose aim has been to limit birth numbers, control population growth and boost economic growth. Having achieved such a low fertility rate, how will China’s population policy evolve in the future? This paper first reviews the history of China’s population policy since 1970 in three stages: 1970–1979; 1980–1999; and after 2000. We explore the impacts of China’s population policy, including relief of pressure on China’s environment and resources, fertility decline, the unexpectedly high male-biased sex ratio at birth (SRB), the coming shortage of labour force, and the rapid aging of the population, and extinction of racial and cultural diversity. We also investigate ethical issues raised by the implementation of the policy and its results. Finally we introduce the controversy over potential adjustment of the policy, acknowledging the problems faced by western countries with low fertility and the counter-measures they have taken. We offer some suggestions that might be appropriate in the Chinese context.

scholarly journals Foraging and farming as niche construction: stable and unstable adaptations

2011 ◽  
Vol 366 (1566) ◽  
pp. 849-862 ◽  
Author(s):  
Peter Rowley-Conwy ◽  
Robert Layton
Keyword(s):  
Food Production ◽  
Animal Species ◽  
Niche Construction ◽  
Political Stability ◽  
Wild Plants ◽  
Wild Plant ◽  
Population Increase ◽  
Small Scale ◽  
History Of ◽  
Abrupt Climatic Change

All forager (or hunter–gatherer) societies construct niches, many of them actively by the concentration of wild plants into useful stands, small-scale cultivation, burning of natural vegetation to encourage useful species, and various forms of hunting, collectively termed ‘low-level food production’. Many such niches are stable and can continue indefinitely, because forager populations are usually stable. Some are unstable, but these usually transform into other foraging niches, not geographically expansive farming niches. The Epipalaeolithic (final hunter–gatherer) niche in the Near East was complex but stable, with a relatively high population density, until destabilized by an abrupt climatic change. The niche was unintentionally transformed into an agricultural one, due to chance genetic and behavioural attributes of some wild plant and animal species. The agricultural niche could be exported with modifications over much of the Old World. This was driven by massive population increase and had huge impacts on local people, animals and plants wherever the farming niche was carried. Farming niches in some areas may temporarily come close to stability, but the history of the last 11 000 years does not suggest that agriculture is an effective strategy for achieving demographic and political stability in the world's farming populations.

scholarly journals Insights into human genetic variation and population history from 929 diverse genomes

2019 ◽  
Author(s):  
Anders Bergström ◽  
Shane A. McCarthy ◽  
Ruoyun Hui ◽  
Mohamed A. Almarri ◽  
Qasim Ayub ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Central Africa ◽  
Population History ◽  
Human Populations ◽  
Genome Sequences ◽  
High Coverage ◽  
Geographical Regions ◽  
History Of ◽  
Different Populations ◽  
Source Populations

AbstractGenome sequences from diverse human groups are needed to understand the structure of genetic variation in our species and the history of, and relationships between, different populations. We present 929 high-coverage genome sequences from 54 diverse human populations, 26 of which are physically phased using linked-read sequencing. Analyses of these genomes reveal an excess of previously undocumented private genetic variation in southern and central Africa and in Oceania and the Americas, but an absence of fixed, private variants between major geographical regions. We also find deep and gradual population separations within Africa, contrasting population size histories between hunter-gatherer and agriculturalist groups in the last 10,000 years, a potentially major population growth episode after the peopling of the Americas, and a contrast between single Neanderthal but multiple Denisovan source populations contributing to present-day human populations. We also demonstrate benefits to the study of population relationships of genome sequences over ascertained array genotypes. These genome sequences are freely available as a resource with no access or analysis restrictions.

scholarly journals Early Performance of `McIntosh' Apple Trees on Several Semidwarf Rootstocks in the 1999 NC-140 Rootstock Trial

HortScience ◽  
2004 ◽  
Vol 39 (4) ◽  
pp. 799D-800
Author(s):  
Wesley Autio* ◽  
John Cline ◽  
Robert Crassweller ◽  
Charles Embree ◽  
Elena Garcia ◽  
...  
Keyword(s):  
Limited Data ◽  
Apple Trees ◽  
Research Project ◽  
Yield Efficiency ◽  
Growing Seasons ◽  
Malus Sylvestris ◽  
Root Suckering ◽  
Early Performance

`McIntosh' apple trees [Malus ×sylvestris (L.) Mill. Var domestica (Borkh.)] on five semidwarfing rootstocks (CG.4814, CG.7707, G.30N, M.7 EMLA, and Supporter 4) were planted at 10 locations (MA, MI MN NS 2 in NY ON PA VT and WI) under the direction of the NC-140 Multistate Research Project. After four growing seasons (through 2002), trees on CG.7707, G.30N, Supporter 4, and M.7 EMLA were significantly larger than those on CG.4814. Cumulative root suckering was most from trees on M.7 EMLA, and least from trees on CG.7707, G.30N, and Supporter 4. Yield per tree in 2002 and cumulatively was greatest from trees on G.30N and least from trees on CG.7707 and M.7 EMLA. In 2002 and cumulatively, CG.4814 resulted in the greatest yield efficiency, and M.7 EMLA resulted in the lowest. In 2002, fruit from trees on M.7 EMLA were largest, and those from trees on CG.4814 were smallest. On average, M.7 EMLA resulted in the largest fruit, and G.30N resulted in the smallest. Limited data will be presented on CG.6210, CG.8, G.30T, and M.26 EMLA, which are planted only at some locations. Data for the fifth season (2003) will be presented.

scholarly journals Early Performance of Two Apple Cultivars in Three Training Systems

HortScience ◽  
1994 ◽  
Vol 29 (9) ◽  
pp. 1004-1007 ◽  
Author(s):  
David C. Ferree
Keyword(s):  
Training System ◽  
Cumulative Yield ◽  
Cross Sectional ◽  
Training Systems ◽  
Growing Seasons ◽  
Golden Delicious ◽  
Slender Spindle ◽  
Flower Density ◽  
Apple Cultivars ◽  
Early Performance

In 1987, `Smoothee Golden Delicious' (`Smoothee') and `Lawspur Rome Beauty' (`Lawspur') apple (Malus domestica Borkh,) trees were planted and trained as central leaders or palmette leaders on M.7 and Mark rootstocks or were planted as slender spindles on Mark rootstocks. `Smoothee' trees were larger and had consistently greater yields and production per unit trunk cross-sectional area (TCA) than `Lawspur' trees. Slender spindle trees had lower early yields per tree and TCA but had greater cumulative yields per hectare than trees in the other training systems. In the fifth and sixth growing seasons, `Smoothee' trained as palmette leaders tended to have higher yields per hectare then central leader trees. Training system had little influence on `Lawspur' tree yields. Limb bending in 1989 increased flower density in 1989 and 1990. Cumulative yield per hectare increased 11% as a result of limb bending of trees on Mark rootstock, but bending had no influence on trees on M.7 rootstock. `Smoothee' on Mark had higher cumulative yields per hectare with the palmette leader and central leader than either `Smoothee' on M.7 in either training system or any combination with `Lawspur'.

scholarly journals Conservation of cultural heritage in minority ethnic regions in northwestern china—an exploration at Kuqa, Xinjiang

2015 ◽  
Vol II-5/W3 ◽  
pp. 343-349
Author(s):  
N. Wu ◽  
X. Zhang
Keyword(s):  
Economic Growth ◽  
Economic Development ◽  
Cultural Heritage ◽  
Living Condition ◽  
Population Increase ◽  
Social Changes ◽  
History Of ◽  
Historic Cities ◽  
Minority Ethnic ◽  
Made In

Kuqa, Xinjiang, is located at northwestern inland china. Traditionally a bridge between eastern and western civilizations, Kuqa had a history of cultural fusion and was left with abundant cultural heritage. As population increase, economic growth and social changes occurred, spontaneous renovation of the old city was affected, in which street fabric and scenes underwent damages. The paper demonstrates attempts made in various projects to achieve conservation of cultural heritage in agreement with economic development and improvement of living condition. The lessons learnt in these projects will be of value to development of other historic cities, especially in minority ethnic regions in China.

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