Less transpiration and good quality thanks to NIR-screen

Materials or additives for greenhouse cover that reflect or absorb a part of the NIR radiation can decrease the cooling requirement for the greenhouse and increase water use efficiency of the crop. By reducing the ventilation requirement, it might even decrease emissions of carbon dioxide from greenhouses with CO2 fertilisatio

Plastic nets in agriculture ; a general review of types and applications

At the moment, there are a large number of agricultural net types on the market characterized by different structural features such as type of material, type and dimensions of threads, texture, mesh size, porosity / solidity and weight; by radiometric properties like color, transmissivity/reflectivity/shading factor; by physical properties like air permeability and several mechanical characteristics such as tensile stress, strength, elongation at break, and durability. Protection from hail, wind, snow, or strong rainfall in fruit-farming and ornamentals, shading nets for greenhouses and nets moderately modifying the microenvironment for a crop are the most common applications. A systematic review of the current state-of-the-art of structural parameters, standard and regulations, most common agricultural net applications, and their supporting structures has been developed by means of a literature study, technical investigations, concerning characteristics and use of nets. As a result, the survey highlighted that in many cases different, not even similar, net types were adopted for the same application and the same cultivations by various growers. Results show that neither growers nor net producers have clear ideas about the relationship between the net typology optimization for a specific application and the construction parameters of the net. The choice often depends on empirical or economic criteria and not on scientific considerations. Moreover, it appears that scientifically justified technical requirements for nets used in specific agricultural applications have not been established yet

Indigenous sovereignties: relational ontologies and environmental management

© 2019 Institute of Australian Geographers Indigenous nations have always and continue to assert their sovereignties to resist colonialism. This paper makes explicit the ways in which environmental management has been and continues to act as a tool of colonialism, particularly by privileging Western science, institutions, and administrative procedures. We argue that to decolonise environmental management, it is crucial to understand and challenge the power relations that underlie it—asking who makes decisions and on what worldview those decisions are based. Indigenous ways of being deeply challenge the foundations of environmental management and the colonising power structures that underlie it, and invite further thought about posthuman and relational ontologies. We provide a range of case studies that showcase the role of Indigenous nations in redefining and reimagining environmental management based on Indigenous sovereignties, knowledges, and ways of being. The case studies emphasise the crucial connection between Indigenous decision-making authority and self-governance for the enhanced protection and health of the environment. We argue that Indigenous agency, grounded in Indigenous governance and sovereignties, is driving innovation and decolonising environmental management by making space for new ways of thinking and being “in place”

Ensemble yield simulations: crop and climate uncertainties, sensitivity to temperature and genotypic adaptation to climate change

Estimates of the response of crops to climate change rarely quantify the uncertainty inherent in the simulation of both climate and crops. We present a crop simulation ensemble for a location in India, perturbing the response of both crop and climate under both baseline (12 720 simulations) and doubled-CO2 (171 720 simulations) climates. Some simulations used parameter values representing genotypic adaptation to mean temperature change. Firstly, observed and simulated yields in the baseline climate were compared. Secondly, the response of yield to changes in mean temperature was examined and compared to that found in the literature. No consistent response to temperature change was found across studies. Thirdly, the relative contribution of uncertainty in crop and climate simulation to the total uncertainty in projected yield changes was examined. In simulations without genotypic adaptation, most of the uncertainty came from the climate model parameters. Comparison with the simulations with genotypic adaptation and with a previous study suggested that the relatively low crop parameter uncertainty derives from the observational constraints on the crop parameters used in this study. Fourthly, the simulations were used, together with an observed dataset and a simple analysis of crop cardinal temperatures and thermal time, to estimate the potential for adaptation using existing cultivars. The results suggest that the germplasm for complete adaptation of groundnut cultivation in western India to a doubled-CO2 environment may not exist. In conjunction with analyses of germplasm and local management practices, results such as this can identify the genetic resources needed to adapt to climate change

Laschamp Excursion at Mono Lake?

The Laschamp Geomagnetic Excursion (ca. 41 ka) and a related increase of cosmogenic nuclides provides a global tie point among sedimentary and ice core records. In the Wilson Creek Formation, Mono Lake, California, the Laschamp Excursion has not been recognized although the so-called Mono Lake excursion was found in the section with an estimated age of about 28 14C ka. However, our reevaluation of the age of the Mono Lake excursion at its type locality using new 14C dates on carbonates and 40Ar/39Ar sanidine dates on ash layers yields an estimate of 38-41 ka. This chronology and the absence of a second excursion in the Wilson Creek Formation suggest that the distinct paleomagnetic feature with negative inclinations at Mono Lake is correlative with the Laschamp Excursion

NIR-selectief scherm : energie-, vochthuishouding en gewasrespons

De helft van de energie-inhoud van zonnestraling valt in het Nabij-Infra-Rood (NIR) golflengte gebied. Het draagt dus bij aan de verwarming van de kas, en aan de verdamping, maar niet aan de assimilatie. Een kasdek dat de NIRstraling reflecteert heeft de potentie om de koelbehoefte van een kas te verlagen en daarmee energieneutraal telen in termen van semi-gesloten eerder mogelijk te maken en de water use efficiency te verhogen. Een reductie van primair energieverbruik voor CO2-opwekking wordt gerealiseerd door een reductie van uitstoot van CO2 door vermindering van de ventilatie bij een vergelijkbare CO2-concentratie ten opzichte van de conventionele kas. Doelstelling van dit experiment was het bepalen van de effecten van een NIR-selectief beweegbaar scherm op kasklimaat en gewas

Floating s- and p-type Gaussian Orbitals

The advantages of including a small number of p-type gaussian functions in a floating spherical gaussian orbital calculation are pointed out and illustrated by calculations on molecules which previously have proved to be troublesome. These include molecules such as F2 with multiple lone pairs and C2H2 with multiple bonds. A feature of the results is the excellent correlation between the orbital energies and those of a double zeta calculation reported by Snyder and Basch

A novel approach for exploring climatic factors limiting current pest distributions: A case study of Bemisia tabaci in north-west Europe and assessment of potential future establishment in the United Kingdom under climate change

This is the final version. Available on open access from Public Library of Science via the DOI in this recordData Availability: All relevant data are within the manuscript and its Supporting Information files.Bemisia tabaci (the tobacco whitefly) is an important agricultural pest of global significance primarily because of its ability to transmit multiple damaging plant viruses. To date, UK outbreaks of the whitefly have been restricted to glasshouses and there are no records of the whitefly establishing outdoors during the summer. This is despite the fact that annual degree-day models (that estimate accumulated warmth over the year above the development threshold), indicate that B. tabaci has the thermal potential for multiple summer generations in the UK. A set of 49 climate indices calculated using the present day climate (1986–2015) were therefore compared between the UK and the south of France, where B. tabaci is able to establish outdoors, to identify the factors limiting its establishment. The number of cold days and nights in summer, as well as the time spent within the whitefly’s optimum temperature range, were most significantly different between the two areas. These indices may impact the development of B. tabaci and offer an explanation for the absence of the whitefly outdoors in the UK during the summer. Further analyses undertaken with climate projections suggest that in a 2–4°C warmer world this pest could pose a risk to outdoor UK crops in July and August. A clear south-north gradient can be demonstrated for these indices. Linking any possible northwards spread of B. tabaci populations outdoors in France with changes in these indices could therefore provide an important indicator of any change in the risks of outdoor populations of this species developing in the UK. The effectiveness of climate indices in pest risk analysis is compellingly demonstrated, and it is recommended that in-depth comparisons of climatic indices between areas of pest presence and absence are conducted in other situations where forecasting the risks of pest establishment are complex and challenging.Joint UK BEIS/Defra Met Office Hadley Centre Climate Programm

A new direction for water management? Indigenous nation building as a strategy for river health

© 2017 by the author(s). Indigenous involvement in Australian water management is conventionally driven by a top-down approach by nonIndigenous government agencies, that asks “how do we engage Indigenous people?” and has culminated in the ineffective “consult” and “service delivery” processes evident in mainstream water management planning. This is a hopeful paper that identifies the critical importance of a “nation-based” approach for effective Indigenous engagement in water planning and policy through the work undertaken by the Ngarrindjeri Regional Authority (NRA) in the Murray Futures program. The NRA is an Indigenous government in the “settled-south” of Australia. Over past decades, the NRA has developed a range of political technologies that act as tools for redeveloping Ngarrindjeri Nationhood after colonial disempowerment and dispossession. These tools enable better collaboration with nonIndigenous governments, especially in natural resource management policy and practice. In turn, this has better enabled the NRA to exercise a decision-making and planning authority over the lands and waters in its jurisdiction, therefore, more effectively exercising its ongoing duty of care as Country. This paper presents a case study of the Sugar Shack Complex Management Plan, codeveloped by the NRA and the South Australian Government in 2015, to demonstrate the benefits that accrue when Indigenous nations are resourced as authorities responsible for reframing water management and planning approaches to facilitate the equitable collaboration of Indigenous and nonIndigenous worldviews. As a marker of the success of this strategy, the Ngarrindjeri Yarluwar-Ruwe Program, in partnership with the South Australian government, recently won the Australian Riverprize 2015 for delivering excellence in Australian river management

Measuring pH variability using an experimental sensor on an underwater glider

Autonomous underwater gliders offer the capability of measuring oceanic parameters continuously at high resolution in both vertical and horizontal planes, with timescales that can extend to many months. An experimental ion sensitive field effect transistor (ISFET) sensor measuring pH on the total scale was attached to a glider during the REP14 – MED experiment in June 2014 in the northwestern Mediterranean Sea. During the deployment, pH was sampled at depths of up to 1000 m, along an 80 km transect over a period of 12 days. Water samples were collected from a nearby ship and analysed for dissolved inorganic carbon concentration and total alkalinity to derive pH for validating the ISFET measurements. The vertical resolution of the pH sensor was good (1 to 2 m), but stability was poor, and the sensor drifted in a non-monotonous fashion. In order to remove the sensor drift, a time-dependent, depth-invariant offset was applied throughout the water column for each dive, reducing the spread of the data by approximately two thirds. Furthermore, the ISFET sensor required temperature and pressure-based corrections, which were achieved using linear regression. Correcting for this decreased the apparent sensor pH variability by a further 13 to 31 %. Sunlight caused an apparent sensor pH decrease of up to 0.1 in surface waters around local noon, highlighting the importance of shielding the sensor away from light in future deployments. The corrected pH from the ISFET sensor is presented along with potential temperature, salinity, potential density anomalies (σθ), and dissolved oxygen concentrations (c(O2)) measured by the glider, providing insights into physical and biogeochemical variability in this region. pH maxima were identified at the depth of the summer chlorophyll maximum, where high c(O2) values were also found. Longitudinal pH variations at depth (σθ > 28.8 kg m−3) highlighted variability of water masses in this region. Higher pH was observed where salinity was > 38.65, and lower pH was found where salinity ranged between 38.3 and 38.65. It seemed that the higher pH was associated with saltier Levantine Intermediate Water. Furthermore, shoaling isopycnals closer to shore coinciding with low pH, high salinity, low c(O2) waters may be indicative of upwelling