Honeybee pollination of crops

Pollination of horticultural and agricultural crops is being recognised throughout Australia by quality growers who wish to improve crop quality and quantity, to increase their returns from produce sold on local and export markets. Some growers are able to target specific high value markets using planned pollination to maximise their income.https://researchlibrary.agric.wa.gov.au/bulletins/1252/thumbnail.jp

Regional scale estimates of baseflow and factors influencing baseflow in the Upper Colorado River Basin

AbstractStudy regionThe study region encompasses the Upper Colorado River Basin (UCRB), which provides water for 40 million people and is a vital part of the water supply in the western U.S.Study focusGroundwater and surface water can be considered a single water resource and thus it is important to understand groundwater contributions to streamflow, or baseflow, within a region. Previously, quantification of baseflow using chemical mass balance at large numbers of sites was not possible because of data limitations. A new method using regression-derived daily specific conductance values with conductivity mass balance hydrograph separation allows for baseflow estimation at sites across large regions. This method was applied to estimate baseflow discharge at 229 sites across the UCRB. Subsequently, climate, soil, topography, and land cover characteristics were statistically evaluated using principal component analysis (PCA) to determine their influence on baseflow discharge.New hydrological insights for the regionResults suggest that approximately half of the streamflow in the UCRB is baseflow derived from groundwater discharge to streams. Higher baseflow yields typically occur in upper elevation areas of the UCRB. PCA identified precipitation, snow, sand content of soils, elevation, land surface slope, percent grasslands, and percent natural barren lands as being positively correlated with baseflow yield; whereas temperature, potential evapotranspiration, silt and clay content of soils, percent agriculture, and percent shrublands were negatively correlated with baseflow yield

Distances sets that are a shift of the integers and Fourier basis for planar convex sets

The aim of this paper is to prove that if a planar set $A$ has a difference set $\Delta(A)$ satisfying $\Delta(A)\subset \Z^++s$ for suitable $s$ than $A$ has at most 3 elements. This result is motivated by the conjecture that the disk has not more than 3 orthogonal exponentials. Further, we prove that if $A$ is a set of exponentials mutually orthogonal with respect to any symmetric convex set $K$ in the plane with a smooth boundary and everywhere non-vanishing curvature, then # (A \cap {[-q,q]}^2) \leq C(K) q where $C(K)$ is a constant depending only on $K$. This extends and clarifies in the plane the result of Iosevich and Rudnev. As a corollary, we obtain the result from \cite{IKP01} and \cite{IKT01} that if $K$ is a centrally symmetric convex body with a smooth boundary and non-vanishing curvature, then $L^2(K)$ does not possess an orthogonal basis of exponentials

When does the action start and finish? Making the case for an ethnographic action research in educational research

This paper explores how ethnographic and action research methodologies can be justifiably combined to create a new methodological approach in educational research. It draws on existing examples in both educational research and development studies that have discussed the use of ethnography and action research in specific projects. Interpretations of ethnography and action research are developed that aim to minimise the epistemological differences between them. The paper also contextualises an ‘ethnographic action research’ approach with reference to an example of the author’s research into participation in three ‘reception’ (first year of schooling) classes in the United Kingdom. It is argued that research into the theme of participation in early years education, using participative methods, was particularly suitable for this new methodological approach

The Australian Early Years Learning Framework: learning what?

Early childhood education and care have assumed importance in many government policy agendas. This attention is often accompanied by calls for greater accountability regarding the anticipated learning outcomes for young children. In Australia, the expected learning outcomes for children aged birth to five years are outlined in the recently published Early Years Learning Framework (EYLF). In this article, the author examines the relationship between the EYLF’s outcomes and subject area or content knowledge. The article draws from post-structural and social constructionist understandings of knowledge as unfinished, contestable and contextual. The author concludes that it is not content knowledge itself that is problematic, but it is the way the child and teacher are often positioned in relation to that knowledge that constrains the potential for effective teaching and learning in the early years. The author suggests that revisiting traditional assumptions about content knowledge extends and develops many of the ideas about teaching and learning that are identified in the EYLF, and opens up new identity positions for both children and early childhood educators

CGILS Phase 2 LES Intercomparison of Response of Subtropical Marine Low Cloud Regimes to CO2\u3c/sub\u3e Quadrupling and a CMIP3 Composite Forcing Change

© 2016. The Authors. Phase 1 of the CGILS large-eddy simulation (LES) intercomparison is extended to understand if subtropical marine boundary-layer clouds respond to idealized climate perturbations consistently in six LES models. Here the responses to quadrupled carbon dioxide (“fast adjustment”) and to a composite climate perturbation representative of CMIP3 multimodel mean 2×CO2 near-equilibrium conditions are analyzed. As in Phase 1, the LES is run to equilibrium using specified steady summertime forcings representative of three locations in the Northeast Pacific Ocean in shallow well-mixed stratocumulus, decoupled stratocumulus, and shallow cumulus cloud regimes. The results are generally consistent with a single-LES study of Bretherton et al. () on which this intercomparison was based. Both quadrupled CO2 and the composite climate perturbation result in less cloud and a shallower boundary layer for all models in well-mixed stratocumulus and for all but a single LES in decoupled stratocumulus and shallow cumulus, corroborating similar findings from global climate models (GCMs). For both perturbations, the amount of cloud reduction varies across the models, but there is less intermodel scatter than in GCMs. The cloud radiative effect changes are much larger in the stratocumulus-capped regimes than in the shallow cumulus regime, for which precipitation buffering may damp the cloud response. In the decoupled stratocumulus and cumulus regimes, both the CO2 increase and CMIP3 perturbations reduce boundary-layer decoupling, due to the shallowing of inversion height

Climate information services available to farming households in Northern Region, Ghana

Climate information services can build the resilience of African farmers to address the increasing threats associated with climate change. This study used household surveys with 200 farmers and focus group discussions to identify the types of climate information services available to farming households in two selected districts (Tolon and Nanton) in the Northern Region of Ghana. The study also identified the dissemination channels and the barriers faced by farmers in their access and use of climate information services for building climate resilience in Ghanaian farming systems. Multinomial logistic regression analysis was used to evaluate the determinants of farmers’ access to climate information services. Results show that 70% of the surveyed farmers had access to varied forms of climate information services. The most prevalent meteorological variables accessible to them were rainfall, temperature, and windstorms in the form of daily and weekly weather forecasts, with only very limited availability and use of seasonal climate forecasts. Radio, television, and advice from extension agents were reported as the major dissemination channels by study respondents. A majority of the farmers reported lack of communication devices, mistrust in weather and climate forecasts, and lack of visual representations in the forecasts as major barriers to access and use of climate information services. The results highlight the importance of timely and reliable access to climate information services in enhancing farmers’ decision-making capacities and the need for training and recruitment of more extension agents to work with farmers on linking climate information services to targeted actions on crop and land management

Marine Low Cloud Sensitivity to An Idealized Climate Change: The CGILS LES Intercomparison

Subtropical marine low cloud sensitivity to an idealized climate change is compared in six large-eddy simulation (LES) models as part of CGILS. July cloud cover is simulated at three locations over the subtropical northeast Pacific Ocean, which are typified by cold sea surface temperatures (SSTs) under well-mixed stratocumulus, cool SSTs under decoupled stratocumulus, and shallow cumulus clouds overlying warmer SSTs. The idealized climate change includes a uniform 2 K SST increase with corresponding moist-adiabatic warming aloft and subsidence changes, but no change in free-tropospheric relative humidity, surface wind speed, or CO2. For each case, realistic advective forcings and boundary conditions are generated for the control and perturbed states which each LES runs for 10 days into a quasi-steady state. For the control climate, the LESs correctly produce the expected cloud type at all three locations. With the perturbed forcings, all models simulate boundary-layer deepening due to reduced subsidence in the warmer climate, with less deepening at the warm-SST location due to regulation by precipitation. The models do not show a consistent response of liquid water path and albedo in the perturbed climate, though the majority predict cloud thickening (negative cloud feedback) at the cold-SST location and slight cloud thinning (positive cloud feedback) at the cool-SST and warm-SST locations. In perturbed climate simulations at the cold-SST location without the subsidence decrease, cloud albedo consistently decreases across the models. Thus, boundary-layer cloud feedback on climate change involves compensating thermodynamic and dynamic effects of warming and may interact with patterns of subsidence change

Marine Low Cloud Sensitivity to An Idealized Climate Change: The CGILS LES Intercomparison

Subtropical marine low cloud sensitivity to an idealized climate change is compared in six large-eddy simulation (LES) models as part of CGILS. July cloud cover is simulated at three locations over the subtropical northeast Pacific Ocean, which are typified by cold sea surface temperatures (SSTs) under well-mixed stratocumulus, cool SSTs under decoupled stratocumulus, and shallow cumulus clouds overlying warmer SSTs. The idealized climate change includes a uniform 2 K SST increase with corresponding moist-adiabatic warming aloft and subsidence changes, but no change in free-tropospheric relative humidity, surface wind speed, or CO2. For each case, realistic advective forcings and boundary conditions are generated for the control and perturbed states which each LES runs for 10 days into a quasi-steady state. For the control climate, the LESs correctly produce the expected cloud type at all three locations. With the perturbed forcings, all models simulate boundary-layer deepening due to reduced subsidence in the warmer climate, with less deepening at the warm-SST location due to regulation by precipitation. The models do not show a consistent response of liquid water path and albedo in the perturbed climate, though the majority predict cloud thickening (negative cloud feedback) at the cold-SST location and slight cloud thinning (positive cloud feedback) at the cool-SST and warm-SST locations. In perturbed climate simulations at the cold-SST location without the subsidence decrease, cloud albedo consistently decreases across the models. Thus, boundary-layer cloud feedback on climate change involves compensating thermodynamic and dynamic effects of warming and may interact with patterns of subsidence change

Effect of climate variability on yields of selected staple food crops in northern Ghana

Agriculture in Ghana is vulnerable to the adverse effects of climate variability. This poses a challenge to food security across the country. Despite this vulnerability, limited research has been conducted to understand the effect of climate variability on the yields of staple food crops in Ghana. This study assessed the effect of climate variability on the yields of selected staple food crops (millet, sorghum, rice, groundnut and maize). The study used the Mann-Kendall trend test and multiple regression analysis to assess how climate variability (in annual rainfall, onset, cessation, number of dry days and temperature) has affected the yields of selected food crops in five districts in northern Ghana (Bole, Nanton, Tolon, Kassena Nankana East and Wa) over a 21-year period (1995–2016). Results suggested a marginal decrease in annual rainfall (p > 0.05) and a significant increase in temperature (p < 0.05) over the period of study in the districts. Variability in the onset, cessation, length of rainy days and number of dry days was statistically significant from year to year, and also across the districts (p < 0.05). Results indicated substantial variability in the yields of the selected staple food crops. Temperature, number of dry days, onset, annual rainfall and cessation explained about 43%, 32%, 30%, 25% and 14%, respectively of the variations in the yields of groundnut, sorghum, millet, maize and rice. Our results generally suggest that the changing climate substantially affects food production in the study districts, highlighting the need for adaptations including the use of agricultural diversification and the greater use of drought tolerant varieties of these staple crops, as well as the continuing investment in crop breeding programmes to enhance drought tolerance