Assessment of phylloplane microorganism populations in Canterbury apple orchards

Microorganism populations on the leaf surface can be an indicator of environmental health in orchards A method was developed to detect changes in these populations in apple orchards Firstly the variation within orchards was investigated by sampling leaves from seven locations within four trees in spring and autumn The population density and species richness of microorganisms when grown on PDA showed tree and season effects (P

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Landscape Enhancements in Apple Orchards: Higher Bumble Bee Queen Species Richness, but No Effect on Apple Quality

Insects ◽

10.3390/insects12050421 ◽

2021 ◽

Vol 12 (5) ◽

pp. 421

Author(s):

Amélie Gervais ◽

Marc Bélisle ◽

Marc J. Mazerolle ◽

Valérie Fournier

Keyword(s):

Species Richness ◽

Bumble Bees ◽

Bumble Bee ◽

Pesticide Use ◽

Apple Orchards ◽

Seed Number ◽

Apple Production ◽

Apple Quality ◽

Effective Pollinators ◽

Quality Weight

Bumble bees are among the most effective pollinators in orchards during the blooming period, yet they are often threatened by the high levels of pesticide use in apple production. This study aimed to evaluate the influence of landscape enhancements (e.g., hedgerows, flower strips) on bumble bee queens in apple orchards. Bumble bee queens from 12 orchards in southern Québec (Canada) were marked, released, and recaptured in the springs and falls of 2017 to 2019. Half of the 12 orchards had landscape enhancements. Apples were harvested in 2018 and 2019 to compare their quality (weight, diameter, sugar level, and seed number) in sites with and without landscape enhancements. Species richness, as well as the occurrence of three species out of eight, was higher in orchards with landscape enhancements than in orchards without such structures. The occurrence of Bombus ternarius was lower in orchards with high levels of pesticide use. Apples had fewer seeds when collected in orchards with landscape enhancements and were heavier in orchards that used more pesticides. Our work provides additional evidence that landscape enhancements improve bumble bee presence in apple orchards and should therefore be considered as a means to enhance pollination within farms.

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Mountain definitions and their consequences

Alpine Botany ◽

10.1007/s00035-021-00265-8 ◽

2021 ◽

Author(s):

Christian Körner ◽

Davnah Urbach ◽

Jens Paulsen

Keyword(s):

Species Richness ◽

Population Density ◽

Climatic Change ◽

Plant Species ◽

Human Population ◽

Short Communication ◽

Plant Species Richness ◽

Mountainous Terrain ◽

Human Population Density

AbstractMountains are rugged structures in the landscape that are difficult to delineate. Given that they host an overproportional fraction of biodiversity of high ecological and conservational value, conventions on what is mountainous and what not are in need. This short communication aims at explaining the differences among various popular mountain definitions. Defining mountainous terrain is key for global assessments of plant species richness in mountains and their likely responses to climatic change, as well as for assessing the human population density in and around mountainous terrain.

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Bird and mammal conservation in Gaoligongshan Region and Jingdong County, Yunnan, China: patterns of species richness and nature reserves

Oryx ◽

10.1046/j.1365-3008.2000.00131.x ◽

2000 ◽

Vol 34 (4) ◽

pp. 275-286 ◽

Cited By ~ 6

Author(s):

Daoying Lan ◽

Robin Dunbar

Keyword(s):

Species Richness ◽

Population Density ◽

Human Population ◽

Yunnan Province ◽

Nature Reserve ◽

Present Situation ◽

Primary Forest ◽

Mammal Conservation ◽

Latitudinal Patterns ◽

Conservation Of Biodiversity

AbstractElevational and latitudinal patterns of species richness for birds and mammals were compared with human population density in relation to nature reserve designation in two areas of Yunnan Province, China. Results suggest that species richness is not the same for the two areas. In Gaoligongshan Region, species richness is inversely correlated with elevation and altitude, while reserve designation is positively correlated with elevation and latitude. In Jingdong County, reserve designations are positively correlated with elevation, but species richness shows no clear trends. In general, the present situation is strongly influenced by human activities. It appears that reserve designation is mismatched with species richness in Gaoligongshan Region, while there is a better fit between the two in Jingdong County. In both areas, however, it appeared that reserves were located primarily in order to reduce conflict with humans rather than to maximize conservation of biodiversity, probably because humans were responsible for forest—especially primary forest—destruction and degradation in the low-lying areas.

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Altitudinal size clines, species richness and population density: case studies in Orthoptera

Journal of Orthoptera Research ◽

10.1665/1082-6467-17.2.157 ◽

2008 ◽

Vol 17 (2) ◽

pp. 157-163 ◽

Cited By ~ 12

Author(s):

Battal Ciplak ◽

Deniz Sirin ◽

M. Sait Taylan ◽

Sarp Kaya

Keyword(s):

Species Richness ◽

Population Density ◽

Case Studies

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Threatened species richness along a Himalayan elevational gradient: quantifying the influences of human population density, range size, and geometric constraints

BMC Ecology ◽

10.1186/s12898-018-0162-3 ◽

2018 ◽

Vol 18 (1) ◽

Cited By ~ 3

Author(s):

Prakash Kumar Paudel ◽

Jan Sipos ◽

Jedediah F. Brodie

Keyword(s):

Species Richness ◽

Population Density ◽

Threatened Species ◽

Human Population ◽

Elevational Gradient ◽

Range Size ◽

Geometric Constraints ◽

Density Range ◽

Human Population Density

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The positive correlation between avian species richness and human population density in Britain is not attributable to sampling bias

Global Ecology and Biogeography ◽

10.1111/j.1466-8238.2006.00288.x ◽

2007 ◽

Vol 16 (3) ◽

pp. 300-304 ◽

Cited By ~ 28

Author(s):

Karl L. Evans ◽

Jeremy J.D. Greenwood ◽

Kevin J. Gaston

Keyword(s):

Species Richness ◽

Population Density ◽

Human Population ◽

Sampling Bias ◽

Avian Species ◽

Human Population Density ◽

Positive Correlation

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Fish population size, and not density, as the determining factor of parasite infection: a case study

Parasitology ◽

10.1017/s0031182003004566 ◽

2004 ◽

Vol 128 (3) ◽

pp. 305-313 ◽

Cited By ~ 58

Author(s):

A. M. BAGGE ◽

R. POULIN ◽

E. T. VALTONEN

Keyword(s):

Species Richness ◽

Population Density ◽

Population Size ◽

Fish Population ◽

Host Population ◽

Fish Length ◽

Total Fish ◽

Infection Parameters ◽

The Mean

The diversity and abundance of parasites vary widely among populations of the same host species. These infection parameters are, to some extent, determined by characteristics of the host population or of its habitat. Recent studies have supported predictions derived from epidemiological models regarding the influence of host population density: parasite abundance and parasite species richness are expected to increase with increasing host population density, at least for directly transmitted parasites. Here, we test this prediction using a natural system in which populations of the crucian carp, Carassius carassius (L.), occur alone, with no other fish species, in a series of 9 isolated ponds in Finland. The ectoparasite communities in these fish populations consist of only 4 species of monogeneans (Dactylogyrus formosus, D. wegeneri, D. intermedius and Gyrodactylus carassii); the total and relative abundance of these 4 species varies among ponds, with one or two of the species missing from certain ponds. Across ponds, only one factor, total fish population size, explained a significant portion of the variance in both the mean number of monogenean species per fish and the mean total abundance of monogenean individual per fish. In contrast, fish population density did not influence either monogenean abundance or species richness, and neither did any of the other variables investigated (mean fish length per pond, number of fish examined per pond, distance to the nearest lake, and several water quality measures). In our system, proximity among fish individuals (i.e. host population density) may not be relevant to the proliferation of monogeneans; instead, the overall availability of host individuals in the host population appeared to be the main constraint limiting parasite population growth.

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Spatial and temporal variation in the infracommunity structure of helminths of Apodemus sylvaticus(Rodentia: Muridae)

Parasitology ◽

10.1017/s0031182000059783 ◽

1989 ◽

Vol 98 (1) ◽

pp. 145-150 ◽

Cited By ~ 32

Author(s):

S. S. J. Montgomery ◽

W. I. Montgomery

Keyword(s):

Species Richness ◽

Northern Ireland ◽

Population Density ◽

Resource Utilization ◽

Species Interactions ◽

Apodemus Sylvaticus ◽

Host Population ◽

Spatial And Temporal Variation ◽

Time And Space ◽

Animal Material

SummaryMean species richness and diversity of the helminth infracommunity of Apodemus sylvaticus in woodland areas of Co. Down, Northern Ireland, varied in time and space. Variation in infracommunity structure among individual hosts, however, always accounted for more than 60% of the variation in the data from different places or different times. Helminth species richness increased with increasing population density, the percentage of the host population 16 weeks old or older, and the proportion of the host population with animal material in their stomachs, at two sites monitored over 33 months. The basis for spatial variation in infracommunity structure is less certain but host dynamics and differences in diet are likely to play some role. It is concluded that analysis at the infracommunity level focuses closely on the potential for species interactions and overlap in resource utilization. Infracommunity structure, at least in the case of A. sylvaticus, varies markedly in time and space and between individual hosts. Such variation should not be ignored in comparative studies.

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The Role of Predators and Other Biotic Agents in Regulating the Population Density of Phytophagous Mites in Ontario Peach Orchards

The Canadian Entomologist ◽

10.4039/ent98808-8 ◽

1966 ◽

Vol 98 (8) ◽

pp. 808-820 ◽

Cited By ~ 58

Author(s):

W. L. Putman ◽

D. H. C. Herne

Keyword(s):

Population Density ◽

Population Growth ◽

Tetranychus Urticae ◽

Considerable Extent ◽

Panonychus Ulmi ◽

Apple Orchards ◽

Rapid Population Growth ◽

One Year ◽

Heavy Mortality

AbstractMore than 40 species of insects and arachnids attack Panonychus ulmi (Koch), Tetranychus urticae Koch, T. canadensis (McGregor), Bryobia arborea Morgan and Anderson, or Aculus cornutus (Banks) in peach orchards of the Niagara Peninsula. The most effective predators attacking P. ulmi are Typhlodromus caudiglans Schuster, Haplothrips faurei Hood, Stethorus punctillum Weise, and Chrysopa spp. Peach orchards lack the predatory mirids characteristic of apple orchards. A condition, presumably disease, caused heavy mortality in one year. Endemic densities of P. ulmi are maintained in that state by predators, chiefly T. caudiglans, that subsist to a considerable extent on other sources of food, whereas epidemics of P. ulmi are reduced largely by other predators, chiefly H. faurei and S. punctillum, that increase in numbers by feeding on the mite during its period of rapid population growth but exert their greatest effect later in the season by destroying the winter eggs.

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