scholarly journals Crop production in the USA is frequently limited by a lack of pollinators

2020 ◽  
Vol 287 (1931) ◽  
pp. 20200922 ◽  
Author(s):  
J. R. Reilly ◽  
D. R. Artz ◽  
D. Biddinger ◽  
K. Bobiwash ◽  
N. K. Boyle ◽  
...  
Keyword(s):  
Wild Species ◽  
Crop Production ◽  
Limiting Current ◽  
Pollinator Limitation ◽  
Wild Bees ◽  
Wild Bee ◽  
The Usa ◽  
Production Value ◽  
Production Areas

Most of the world's crops depend on pollinators, so declines in both managed and wild bees raise concerns about food security. However, the degree to which insect pollination is actually limiting current crop production is poorly understood, as is the role of wild species (as opposed to managed honeybees) in pollinating crops, particularly in intensive production areas. We established a nationwide study to assess the extent of pollinator limitation in seven crops at 131 locations situated across major crop-producing areas of the USA. We found that five out of seven crops showed evidence of pollinator limitation. Wild bees and honeybees provided comparable amounts of pollination for most crops, even in agriculturally intensive regions. We estimated the nationwide annual production value of wild pollinators to the seven crops we studied at over $1.5 billion; the value of wild bee pollination of all pollinator-dependent crops would be much greater. Our findings show that pollinator declines could translate directly into decreased yields or production for most of the crops studied, and that wild species contribute substantially to pollination of most study crops in major crop-producing regions.

scholarly journals The importance of wild bee communities as urban pollinators and the influence of honeybee hive density

2021 ◽  
Vol 29 ◽  
pp. 204-230
Author(s):  
Julie Anne Weissmann ◽  
Iris Rebecca Magdalena Walldorf ◽  
Hanno Schaefer
Keyword(s):  
Urban Areas ◽  
Weather Conditions ◽  
Fruit Trees ◽  
Observation Time ◽  
Wild Bees ◽  
Pollination Success ◽  
Wild Bee ◽  
Negative Effect ◽  
Bee Communities

While urban beekeeping is on the rise, data on the role of wild bee communities as crop pollinators in cities is still scarce. We analysed wild bee visitation rates on apple, plum, cherry, pear, blackberry, raspberry, and strawberry in a Bavarian city with a very high honeybee density of c. 19 hives/km2. During 137.5 hours of observation time, we observed 52 wild bee species on the studied crop plants. During more than 50 h of observation time on fruit trees in flower, we found that wild bees provided 41% of the total bee visits, honeybees the remaining 59%. Honeybee hive density had a significantly negative effect on wild bee abundance. Bumblebees appeared more tolerant to poor weather conditions than all other bee groups. Wild bee species richness on apple flowers was not significantly impacted by flower diversity in the surroundings of the trees. Together, our results suggest that species-rich wild bee communities in urban areas are important for pollination success in common fruit crops, especially under unstable spring weather conditions. Bee-friendly management of urban spaces should be prioritised to support wild bee communities as well as the increasing number of honeybees in cities.

EPIZOOTOLOGICAL FEATURES OF MODERN CATTLE LEUKEMIA

1970 ◽  
pp. 53-58
Author(s):  
V. V. Makarov ◽  
D. A. Lozovoy
Keyword(s):  
Dairy Cattle ◽  
Western Europe ◽  
Control Programs ◽  
Foreign Countries ◽  
Negative Order ◽  
Dairy Cattle Breeding ◽  
The Usa ◽  
Epizootic Process ◽  
National Programs

  Enzootic bovine leucosis (EBL) has been known for more than a century and a half. Its occurrence and registration may have historically been associated with intensive breeding of dairy cattle in Western Europe to increase target productivity. It is known that any limiting intervention in the nature of the animal organism is always accompanied by an uncontrolled and unpredictable change in the genotype of a wider range than the required, particularly negative order. In particular, a decrease in the resistance to macroorganisms and the possibility of the new diseases emergence, including infectious ones (for example, immunodeficiencies such as BLAD syndrome of black-motley cattle and stress syndrome in pigs, the occurrence of scrapie and other slow sheep infections). In the last two decades of the last century, in many disadvantaged countries, primarily Western European, national programs for the eradication of EBL have been developed and subsequently successfully implemented. First of all the motivation was the economy of dairy cattle breeding (mainly the extension of productive age, as well as the tightening of requirements in international trade in cattle and bull products, breeding, pricing, etc.). In an analytical article are reviewed the elements of epizootology of EBL in the foreign countries with special attention to the situation in the USA, scenarios of various control programs, and promising methods for assessing the role of infected animals in the epizootic process. A critical assessment of the problem of EBL in the Russian Federation is given, the reasons for the ineffectiveness of against leucosis measures are discussed.

The Lattimore case

2017 ◽  
Author(s):  
Angela Penrose
Keyword(s):  
Cold War ◽  
Internal Security ◽  
Johns Hopkins University ◽  
The Usa ◽  
The 1950S ◽  
Witch Hunt

Edith’s career and collaboration with Fritz Machlup at Johns Hopkins University flourished and she began work on the growth of the firm, and studied the Hercules Powder Company. As Cold War tensions increased during the 1950s she and Penrose became involved in the defence of their friend and colleague Owen Lattimore who was named as the top Soviet spy by Senator McCarthy. The chapter covers the persecution of Lattimore, his trials, the role of Judge Luther Youngdahl, and the operation of his defence fund. Other friends of E. F. Penrose became victims of the anti-communist ‘witch hunt’, he grew increasingly disillusioned with the USA, and determined he must leave. In 1953 Edith and Penrose testified before the Senate Internal Security Subcommittee. They were also investigated by the FBI. After five years the case against Lattimore was dropped. Edith’s father died and her brother Harvey was killed in an air accident.

Influence of Nesting Characteristics on Health of Wild Bee Communities

2020 ◽  
Vol 65 (1) ◽  
pp. 39-56 ◽  
Author(s):  
Alexandra Harmon-Threatt
Keyword(s):  
Climate Change ◽  
Nest Site ◽  
Site Conditions ◽  
Wild Bees ◽  
Nesting Biology ◽  
Habitat Disturbances ◽  
Wild Bee ◽  
Growth Development ◽  
Bee Communities ◽  
Nest Initiation

Nest site availability and quality are important for maintaining robust populations and communities of wild bees. However, for most species, nesting traits and nest site conditions are poorly known, limiting both our understanding of basic ecology for bee species and conservation efforts. Additionally, many of the threats commonly associated with reducing bee populations have effects that can extend into nests but are largely unstudied. In general, threats such as habitat disturbances and climate change likely affect nest site availability and nest site conditions, which in turn affect nest initiation, growth, development, and overwintering success of bees. To facilitate a better understanding of how these and other threats may affect nesting bees, in this review, I quantify key nesting traits and environmental conditions and then consider how these traits may intersect with observed and anticipated changes in nesting conditions experienced by wild bees. These data suggest that the effects of common threats to bees through nesting may strongly influence their survival and persistence but are vastly understudied. Increasing research into nesting biology and incorporating nesting information into conservation efforts may help improve conservation of this declining but critical group.

scholarly journals Identity of mass-flowering crops moderates functional trait composition of pollinator communities

2021 ◽  
Author(s):  
Nicole Beyer ◽  
Felix Kirsch ◽  
Doreen Gabriel ◽  
Catrin Westphal
Keyword(s):  
Faba Bean ◽  
Management Practices ◽  
Functional Trait ◽  
Flower Morphology ◽  
Landscape Diversity ◽  
Floral Resources ◽  
Wild Bees ◽  
Natural Habitats ◽  
Mass Flowering ◽  
Wild Bee

Abstract Context Pollinator declines and functional homogenization of farmland insect communities have been reported. Mass-flowering crops (MFC) can support pollinators by providing floral resources. Knowledge about how MFC with dissimilar flower morphology affect functional groups and functional trait compositions of wild bee communities is scarce. Objective We investigated how two morphologically different MFC, land cover and local flower cover of semi-natural habitats (SNH) and landscape diversity affect wild bees and their functional traits (body size, tongue length, sociality, foraging preferences). Methods We conducted landscape-level wild bee surveys in SNH of 30 paired study landscapes covering an oilseed rape (OSR) (Brassica napus L.) gradient. In 15 study landscapes faba beans (Vicia faba L.) were grown, paired with respective control landscapes without grain legumes. Results Faba bean cultivation promoted bumblebees (Bombus spp. Latreille), whereas non-Bombus densities were only driven by the local flower cover of SNH. High landscape diversity enhanced wild bee species richness. Faba bean cultivation enhanced the proportions of social wild bees, bees foraging on Fabaceae and slightly of long-tongued bumblebees. Solitary bee proportions increased with high covers of OSR. High local SNH flower covers mitigated changes of mean bee sizes caused by faba bean cultivation. Conclusions Our results show that MFC support specific functional bee groups adapted to their flower morphology and can alter pollinators` functional trait composition. We conclude that management practices need to target the cultivation of functionally diverse crops, combined with high local flower covers of diverse SNH to create heterogeneous landscapes, which sustain diverse pollinator communities.

Social Development and Police Reform: Some Reflections on the Concept and Purpose of Policing and the Implications for Reform in the UK and USA

2020 ◽  
Author(s):  
Andrew Williams ◽  
Craig Paterson
Keyword(s):  
Social Development ◽  
Conceptual Understanding ◽  
Critical Question ◽  
Police Reform ◽  
Liberal Democratic ◽  
The Usa ◽  
Anglo American ◽  
The Uk ◽  
Common Understanding

Abstract The increase in calls for police reform following the death of George Floyd has led to renewed debate about social inequality and the role of policing in society. Modern bureaucratic police systems emerged from locally administered structures and Anglo-American policing models continue to be aligned, to varying degrees, with the political, socio-cultural, legal, and ideological aspects of contemporary liberal democratic society with its emphasis on democratic localism and decentralised accountability. However, at a time when society is reimagining itself and technology, government, and nations are radically re-shaping themselves, a critical question is whether there is a sufficiently common philosophical and conceptual understanding of policing to support its development rather than just a common understanding of police functions. This is profoundly important when considering the current calls for reform of policing in the USA and other western democratic states. The article argues that there is an urgent need to reconsider how we conceptualize policing and its relationship with social development.

scholarly journals The distribution of wealth in Spain and the USA: the role of socioeconomic factors

SERIEs ◽  
2021 ◽  
Author(s):  
Pedro Salas-Rojo ◽  
Juan Gabriel Rodríguez
Keyword(s):  
Socioeconomic Factors ◽  
Parental Education ◽  
Wealth Inequality ◽  
Latent Factors ◽  
Distribution Of Wealth ◽  
The Usa ◽  
Value Decomposition ◽  
Counterfactual Decomposition ◽  
Distribution Of Income

AbstractThe literature has typically found that the distribution of socioeconomic factors like education, labor status and income does not account for the remarkable wealth inequality disparities between countries. As a result, their different institutions and other latent factors receive all the credit. Here, we propose to focus on one type of wealth inequality, the inequality of opportunities (IOp) in wealth: the share of overall wealth inequality explained by circumstances like inheritances and parental education. By means of a counterfactual decomposition method, we find that imposing the distribution of socioeconomic factors of the USA into Spain has little effect on total, financial and real estate wealth inequality. On the contrary, these factors play an important role when wealth IOp is considered. A Shapley value decomposition shows that the distribution of education and labor status in the USA consistently increase wealth IOp when imposed into Spain, whereas the opposite effect is found for the distribution of income.

Sign in / Sign up

Export Citation Format

Share Document