scholarly journals Assessing agri-environmental schemes for semi-natural grasslands during a 5-year period: can we see positive effects for vascular plants and pollinators?

2019 ◽  
Vol 28 (14) ◽  
pp. 3989-4005 ◽  
Author(s):  
Åke Berg ◽  
Erik Cronvall ◽  
Åsa Eriksson ◽  
Anders Glimskär ◽  
Matthew Hiron ◽  
...  
Keyword(s):  
Species Richness ◽  
Vascular Plants ◽  
Grazing Intensity ◽  
Landscape Composition ◽  
Negative Effects ◽  
Positive Effects ◽  
Vegetation Height ◽  
Natural Grasslands ◽  
Species Richness And Abundance ◽  
Over Time

Abstract An important function of agri-environmental schemes (AES) is to change management of pastures to better conserve biodiversity. However, the effects of most AES on biodiversity are poorly understood, especially when it comes to effects of AES management over time. The main aim of this study is to investigate if the species richness and abundance of grassland specialists of vascular plants and two important insect pollinator groups (bumblebees and butterflies) differ over time (5 years) in pastures with AES management (two value levels; general values and special values) and pastures without AES management. We also investigate if local vegetation characteristics and landscape composition relate to species richness in semi-natural grasslands. Using data from more than 400 sites we found that species richness of vascular plants (grassland specialists) was higher in pastures with AES management (for special and general values) compared to those without AES, which implies that these schemes do have value of the conservation of plant diversity. However, species richness and abundance of butterflies (grassland specialists) and bumblebees (all species) did not differ significantly among the three AES categories. We found no evidence that the type of AES management caused any changes in species richness of plants, butterflies or bumblebees during the 5 year period of our investigation. It appears that AES management that encourages uniform and minimum levels of grazing can have both positive and negative effects on biodiversity. For example, pollinators may benefit from a lower grazing intensity that could increase flower richness and heterogeneity in vegetation height. However, low grazing intensity may lead to increased cover of trees and shrubs, which can have negative effects for both insect pollinators and vascular plants. The effects of landscape composition were weak and only species richness of bumble bees were associated with landscape composition. Designing management regimes to maintain suitably heterogeneous vegetation layer, and continued long-term monitoring of biodiversity will be critical for safeguarding culturally and functionally important semi-natural grasslands.

scholarly journals Low effect on open-farmland birds of young afforestations in heterogeneous Mediterranean croplands

2014 ◽  
Author(s):  
Juan S. Sánchez-Oliver ◽  
José M. Rey Benayas ◽  
Luis M. L.M. Carrascal
Keyword(s):  
Species Richness ◽  
Bird Species ◽  
Agricultural Landscapes ◽  
Tree Plantations ◽  
Conservation Value ◽  
Farmland Birds ◽  
Negative Effects ◽  
Bird Species Richness ◽  
Positive Effects ◽  
The One

Afforestation programs such as the one promoted by the EU Common Agricultural Policy have spread tree plantations on former cropland. These afforestations attract generalist forest and ubiquitous species but may cause severe damage to open habitat species, especially birds of high conservation value. We investigated the effects of young (< 20 yr) tree plantations dominated by pine P. halepensis on bird communities inhabiting the adjacent open farmland habitat in central Spain. We hypothesize that pine plantations with larger surface, and areas at shorter distances from plantations, would result in lower bird species richness and conservation value of open farmland birds. Regression models controlling for the influence of land use types around plantations revealed significant positive effects of distance to pine plantation edge on community species richness in winter, and negative effects on an index of conservation concern (SPEC) during the breeding season. However, plantation area did not have any effect on species richness or community conservation value. Our results indicate that pine afforestation of Mediterranean cropland in heterogeneous agricultural landscapes has an overall low detrimental effect on bird species that are characteristic of open farmland habitat.

Community and infracommunities of metazoan parasites in Hemiodus unimaculatus (Hemiodontidae) from Jari River basin, a tributary of Amazon River (Brazil)

2021 ◽  
Vol 30 (4) ◽  
Author(s):  
Odonei Moia Almeida ◽  
Marcos Sidney Brito Oliveira ◽  
Marcos Tavares-Dias
Keyword(s):  
Species Richness ◽  
River Basin ◽  
Parasite Community ◽  
Amazon Region ◽  
Amazon River ◽  
Metazoan Parasites ◽  
Random Dispersion ◽  
Northern Brazil ◽  
Species Richness And Abundance ◽  
Over Time

Abstract Parasites are an important part of biodiversity, and knowledge of species and their relationship with their hosts helps in monitoring an ecosystem over time. The aim of this study was to investigate the fauna of metazoan parasites in Hemiodus unimaculatus from the Jari River, in the eastern Amazon region, northern Brazil. Of the fish examined, 96.7% were parasitized by one or more species, and a total of 336 parasites such as Dactylogyridae gen. sp.1, Dactylogyridae gen. sp.2, Dactylogyridae gen. sp.3, Dactylogyridae gen. sp.4, Gyrodactilydae gen. sp., Urocleidoides sp.1, Urocleidoides sp.2, Urocleidoides sp.3, metacercariae of Digenea gen. sp., Procamallanus (Spirocamallanus) inopinatus, Contracaecum sp., Neoechinorhynchus sp. and Acarina gen. sp. The parasite community showed low Brillouin diversity (0.58 ± 0.29), low evenness (0.44 ± 0.21) and low species richness (7.40 ± 3.83). There was a predominance of ectoparasites, mainly monogeneans and digeneans. The parasites showed an aggregate dispersion, except for P. (S.) inopinatus, which had a random dispersion. The size of the hosts had no effect on diversity, species richness and abundance of parasites, but other factors structured the parasite community. This is the first study on the parasite community and infracommunities in H. unimaculatus.

scholarly journals Decline in Aboveground Biomass Due to Fragmentation in Subtropical Forests of China

Forests ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 617
Author(s):  
Chunyu Shen ◽  
Nannan Shi ◽  
Shenglei Fu ◽  
Wanhui Ye ◽  
Lei Ma ◽  
...  
Keyword(s):  
Species Richness ◽  
Forest Fragmentation ◽  
Aboveground Biomass ◽  
Biodiversity Loss ◽  
Average Diameter ◽  
Forest Fragments ◽  
Biomass Storage ◽  
Positive Effects ◽  
Fragmented Forests ◽  
Species Richness And Abundance

Fragmentation has long been considered the primary cause for ecosystem degradation and biodiversity loss worldwide. Forest fragmentation affects ecosystem functioning and biodiversity in multiple ways. Here, we ask how forest fragmentation influences aboveground biomass storage (AGB) in sub-tropical forests in China. We established 207 20 m × 20 m plots within 69 forest fragments of varying size. Forest fragmentation process simulation was carried out via repeated quadrat sampling using different sized quadrats in two non-fragmented stands. AGB was estimated and compared across forest fragments and quadrats with different sizes within two non-fragmented stands. Our results indicate that AGB is significantly lower in forest fragments than in quadrats within two non-fragmented forests. In addition, species richness and abundance were lower in fragmented stands, respectively. In fragmented forests, the average diameter at breast height (DBH) increased with decreasing patch size, while declined for non-fragmented plots. Species richness, abundance, and mean DBH have strongly positive effects on AGB. This was the case both in forest fragments and quadrats within two non-fragmented forests. Forest fragmentation leads to lower richness, lower abundance, and higher mean DBH in forest fragments than in the two non-fragmented forests. Our results suggest that forest fragmentation increases edge habitats, which drastically decreases forests aboveground biomass storage. These results show that land degradation not only reduces the area of forests, but also reduces the aboveground biomass carbon density of forests.

The effect of college acquisitions and mergers on student dropout behaviour: evidence from the UK

2020 ◽  
Vol 72 (3) ◽  
pp. 606-632
Author(s):  
Rossella Iraci Capuccinello ◽  
Steve Bradley
Keyword(s):  
Further Education ◽  
Drop Out ◽  
Dropping Out ◽  
Negative Effects ◽  
Policy And Practice ◽  
Student Dropout ◽  
Positive Effects ◽  
One Year ◽  
The Uk ◽  
Over Time

Abstract We investigate the effect of college acquisitions on the probability of students dropping out of college. Using administrative data for the further education (FE) sector, which covers multiple cohorts, we estimate matching models and combine them with difference-in-differences methods to remove the effects of unobserved student and college heterogeneity. Overall our findings show that acquisitions reduce the probability of dropout by 0.01 percentage points, but this varies in magnitude and direction over time. In general, positive effects of acquisitions on drop out behaviour tend to be small (e.g. 0.001 for acquisitions in 2004) and dissipate over time, whereas negative effects persist and tend to increase in magnitude over time (e.g. −0.05 one year later and −0.07 two years later). We discuss the implications for policy and practice in the sector, as well as suggesting a need for similar analyses in other education sectors, such as primary and secondary schooling.

scholarly journals Impacts of sheep versus cattle livestock systems on birds of Mediterranean grasslands

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rita F. Ramos ◽  
João A. Diogo ◽  
Joana Santana ◽  
João P. Silva ◽  
Luís Reino ◽  
...  
Keyword(s):  
Species Richness ◽  
Grazing Pressure ◽  
Bird Diversity ◽  
Stocking Rate ◽  
Bird Populations ◽  
Positive Effects ◽  
Vegetation Height ◽  
Mediterranean Grasslands ◽  
Negative Impacts ◽  
Livestock Systems

AbstractMediterranean pastures are experiencing strong changes in management, involving shifts from sheep to cattle-based livestock systems. The impacts of such shifts on biodiversity are still poorly understood. Here, we sought to contrast the grazing regime, vegetation structure, bird species richness and abundance, between sheep and cattle grazed parcels, to understand the mechanisms through which management decisions impact farmland birds. During spring 2019, we characterized livestock management, bird populations and sward structure in 23 cattle and 27 sheep grazed parcels. We used a Structural Equation Model to infer the direct and indirect effects of sheep and cattle grazing on birds. Although no effects were found on overall species richness, there were species-specific responses to sheep and cattle grazed systems. Grazing pressure (variable integrating stocking rate and the number of days in the parcel) had negative impacts on the prevalence/abundance of Zitting Cisticola, Corn Bunting and Little Bustard, either directly or indirectly, through the effects of grazing pressure on vegetation height. Animal density and vegetation cover had direct positive effects in Galerida spp. and Common Quail, respectively. Zitting Cisticola and Little Bustard also showed a direct response to livestock type. Our study emphasizes the importance of grazing pressure as a driver of negative impacts for bird populations in Mediterranean grasslands. Since the ongoing transition from sheep to cattle-based systems involves increases in stocking rate, and therefore potentially higher grazing pressure, we propose a policy change to cap the maximum allowed grazing pressure. At the landscape scale, a mix of sheep and cattle grazed fields would be beneficial for maintaining bird diversity.

scholarly journals Scolytinae y Platypodinae (Coleoptera: Curculionidae) de dos áreas de conservación en Tabasco, México

2016 ◽  
Vol 64 (1) ◽  
pp. 319 ◽  
Author(s):  
Manuel Pérez-De la Cruz ◽  
Manuel A. Hernández-May ◽  
Aracely De la Cruz-Pérez ◽  
Saúl Sánchez-Soto
Keyword(s):  
Population Dynamics ◽  
Species Richness ◽  
Ethyl Alcohol ◽  
New Records ◽  
Botanical Garden ◽  
Common Species ◽  
Wide Range ◽  
Ecological Reserve ◽  
Species Richness And Abundance ◽  
Over Time

The Scolytinae and Platypodinae are group of widely distributed tropical insects that are capable of using a wide range of hosts. The study of diversity associated with conservation sites allows estimating the richness and abundance of species, their population dynamics as well as understanding the population behavior over time. The species richness and abundance of Scolytinae and Platypodinae was studied in the Chontalpa Ecological Reserve (REC) and the José Narciso Rovirosa Botanical Garden (JBU) in Tabasco, Mexico. Insects were captured with ethyl alcohol traps. A total of 7 057 specimens belonging to 46 species and 26 genera were collected and identified; 42 species from 23 genera belong to Scolytinae and four species from three genera to Platypodinae. The species Bothrosternus foveatus (Blackman, 1943); Dendroterus luteolus (Schedl, 1951); Dendrocranulus guatemalensis (Hopkins, 1915); Micracis swainei (Blackman, 1920); Pseudothysanoes tenellus (Wood, 1971) y Ambrosiodmus obliquus (Leconte, 1878) are new records for the state of Tabasco. The species Corthylus papulans Eichhoff, 1869 with 2 509 specimens (35.55); Xyleborus volvulus (Fabricius, 1775) with 1 435 (20.33); and Xyleborus affinis Eichhoff, 1868 with 1 061 (15.03) were the most common species, representing 70.9 % of total. The population dynamics of these insects showed its highest peak during February and March with 2 728 specimens in JBU and December with 322 in REC of year 2010.

Influence of canopy-forming algae on temperate sponge assemblages

2015 ◽  
Vol 96 (2) ◽  
pp. 351-362 ◽  
Author(s):  
César A. Cárdenas ◽  
Simon K. Davy ◽  
James J. Bell
Keyword(s):  
Species Richness ◽  
New Zealand ◽  
Energy Flow ◽  
Light Regime ◽  
Predictor Variables ◽  
Sponge Species ◽  
Negative Effects ◽  
Turf Algae ◽  
Canopy Removal ◽  
Species Richness And Abundance

Experimental removals of the dominant canopy-forming kelp Ecklonia radiata were conducted at two sites on rocky walls in New Zealand and monitored for approximately 1.5 years. We hypothesized that the removal of the E. radiata canopy would affect the structure of subcanopy assemblages, such that there would be a reduction in sponge species richness and abundance. Furthermore, we investigated the biological and physical (predictor) variables that best explained variability in sponge assemblages after canopy removal. Canopy removal led to a community dominated by turf algae, which corresponded with a decrease in sponge abundance and richness. Our results suggest that the Ecklonia canopy may positively influence the presence of sponge species such as Crella incrustans; we propose that the canopy may allow its coexistence with turf algae underneath the canopy by altering the light regime and other environmental factors, which may be detrimental for some species. Our results highlight how any loss of canopy-forming species might have negative effects on sponge assemblages, which could affect the energy flow and the overall biodiversity found in these habitats.

scholarly journals Associations Between Defence-Style, Eating Disorder Symptoms, and Quality of Life in Community Sample of Women: A Longitudinal Exploratory Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Phillip Aouad ◽  
Phillipa Hay ◽  
Nasim Foroughi ◽  
Suzanne M. Cosh ◽  
Haider Mannan
Keyword(s):  
Quality Of Life ◽  
Psychological Distress ◽  
Community Sample ◽  
Extended Period ◽  
Eating Pathology ◽  
Negative Effects ◽  
Positive Effects ◽  
Positive Effect ◽  
Over Time

Background and Aim: Eating Disorders (EDs) impact an estimated 15% of the global population and are linked to maladaptive defence-styles (coping strategies) and poorer mental health outcomes. Defence-styles have been grouped into immature, neurotic, and mature behaviours. Studies have yet to examine all three defence-styles in ED symptomatic individuals over an extended period of time. The current study aimed to investigate using converse analysis the relationships between defence-style and ED outcomes over a 5-years period.Methods: Participants (n = 216, mean age 33 years) were recruited through the Women's Eating and Health Literacy study, with the current study examining a 5-years period of two waves (year-4 and year-9). The current study tested associations over time between eating pathology (EDE-Q), psychological distress (K10), mental and physical health related quality of life (M/PHRQoL, SF-12), and defence-style (DSQ-40).Results: Mature, immature and neurotic defence-styles did not significantly change over 5 years. Over the same period, only PHRQoL significantly predicted mature defence-styles having positive effect. Both MHRQoL and PHRQoL significantly predicted immature defence-styles having positive and negative effects, respectively. Psychological distress, PHRQoL and weight concern significantly predicted neurotic defence-styles having positive effects except for psychological distress. PHRQoL, MHRQoL, restraint and eating concern significantly predicted overall eating pathology having positive effects except for PHRQoL and MHRQoL. Conversely, among the defence-style variables, over 5 years, both immature and neurotic defence-styles significantly predicted psychological distress having positive effects, immature and mature defence-styles significantly predicted MHRQoL having negative and positive effects, respectively, while only immature defence-styles significantly predicted overall eating pathology having positive effect.Conclusions: The results of the current study suggest that immaturity and neuroticism but not maturity were the defence-style variables predicting psychological distress over a 5-years period while conversely psychological distress predicted only neurotic defence styles. The findings of the current study may suggest that without intervention, mature, immature and neurotic defence-styles may largely remain immutable to significant shifts over time. Limitations in the current study included limited demographic representation. The current study is anticipated to generate considerations into treatments that could strengthen defence-styles in individuals with increased eating pathology.

scholarly journals Low effect of young afforestations on bird communities inhabiting heterogeneous Mediterranean cropland

PeerJ ◽  
2015 ◽  
Vol 3 ◽  
pp. e1453 ◽  
Author(s):  
Juan S. Sánchez-Oliver ◽  
José M. Rey Benayas ◽  
Luis M. Carrascal
Keyword(s):  
Species Richness ◽  
Agricultural Landscapes ◽  
Bird Communities ◽  
Tree Plantations ◽  
Conservation Value ◽  
Negative Effects ◽  
Positive Effects ◽  
High Conservation ◽  
Conservation Concern ◽  
The One

Afforestation programs such as the one promoted by the EU Common Agricultural Policy have spread tree plantations on former cropland. These afforestations attract generalist forest and ubiquitous species but may cause severe damage to open habitat species, especially birds of high conservation value. We investigated the effects of young (<20 yr) tree plantations dominated by pineP. halepensison bird communities inhabiting the adjacent open farmland habitat in central Spain. We hypothesize that pine plantations located at shorter distances from open fields and with larger surface would affect species richness and conservation value of bird communities. Regression models controlling for the influence of land use types around plantations revealed positive effects of higher distance to pine plantation edge on community species richness in winter, and negative effects on an index of conservation concern (SPEC) during the breeding season. However, plantation area did not have any effect on species richness or community conservation value. Our results indicate that the effects of pine afforestation on bird communities inhabiting Mediterranean cropland are diluted by heterogeneous agricultural landscapes.

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