Influence of reduced irrigation on beneficial invertebrates in vineyards

2006 ◽  
Vol 46 (10) ◽  
pp. 1389 ◽  
Author(s):  
L. J. Thomson

An important aspect of increasing the sustainability of agricultural production in dry continents such as Australia is decreasing water use. In this study full irrigation is compared with partial rootzone drying, a method that uses targeted controlled watering to reduce water use while maintaining production in vineyards. The impact of the 2 irrigation methods on invertebrates with potential to influence productivity (pests, predators, parasitoids and soil macroinvertebrates) in a vineyard in south-eastern Australia is also investigated. Invertebrates were sampled at ground level and in the canopy using 3 methods: pitfall traps and 2 types of sticky trap. Earthworms were sampled by hand sorting soil. Initial sorting of the collections was to the order level. The implementation of partial rootzone drying throughout the growing season (December–March) over 2 consecutive years had little effect on the invertebrate orders analysed. Only 2 generalist predator orders (Araneae and Coleoptera) and earthworms (Haplotaxida) were significantly affected under conditions of water stress. These data suggest that reduction of irrigation of the magnitude required for partial rootzone drying has limited consequences for natural enemies of vineyard pests and soil macroinvertebrates in the short term.

2013 ◽  
Vol 4 (1) ◽  
pp. 141-153
Author(s):  
Julia Miller

In 1963 Sydneysiders, having suffered four dismal summers in a row and wetter than usual weather during the 1950s, looked back to those lazy, hazy days of the summers of a distant past where the sky arched blue over the gleaming golden sand of the quintessential Australian beach. City dwellers in the dying months of 1963, worried by persistent rain and cool temperatures, concluded that soggy weather had become the established norm. More recent experiences of wet summers in Sydney have blamed this on La Niña—a short-term climate driver that brought heavy rains and flooding to many districts of eastern Australia. This article examines the impact of natural climate cycles on attitudes to weather in Sydney. It shows how an investigation of the cultural interface of weather and climate can illuminate attitudes that impact on our ability to plan for climate change into the future.


2008 ◽  
Vol 98 (6) ◽  
pp. 631-639 ◽  
Author(s):  
N. Desneux ◽  
R.J. O'Neil

AbstractGeneralist insect predators can significantly impact the dynamics of pest populations; and, using alternative prey, they can rapidly establish in disturbed agroecosystems. However, indirect interactions between prey can occur, leading to either increased or decreased predation on focal prey. The present paper demonstrates how alternative prey can disrupt predation by the hemipteran Orius insidiosus on the soybean aphid Aphis glycines via short-term indirect interactions. We used laboratory microcosms to measure the impact of the predator on the population growth of the aphid in the presence of alternative prey, soybean thrips Neohydatothrips variabilis, and we characterized the foraging behaviour of the predator to assess prey preference. We showed that O. insidiosus predation on aphids was reduced in the presence of thrips and that this positive impact on aphids increased as thrips density increased. Results from the behavioural experiment support the hypothesis of a prey preference toward thrips. When prey-pest ratio is aphid-biased, short-term apparent commensalism between prey occurs in favour of the most abundant prey (aphids) with no switching behaviour appearing in O. insidiosus. These results demonstrate that potential indirect interactions should be taken into account when considering O. insidiosus as a biocontrol agent against the soybean aphid.


Author(s):  
Shuqiong Huang ◽  
Hao Xiang ◽  
Wenwen Yang ◽  
Zhongmin Zhu ◽  
Liqiao Tian ◽  
...  

Tuberculosis (TB) has a very high mortality rate worldwide. However, only a few studies have examined the associations between short-term exposure to air pollution and TB incidence. Our objectives were to estimate associations between short-term exposure to air pollutants and TB incidence in Wuhan city, China, during the 2015–2016 period. We applied a generalized additive model to access the short-term association of air pollution with TB. Daily exposure to each air pollutant in Wuhan was determined using ordinary kriging. The air pollutants included in the analysis were particulate matter (PM) with an aerodynamic diameter less than or equal to 2.5 micrometers (PM2.5), PM with an aerodynamic diameter less than or equal to 10 micrometers (PM10), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and ground-level ozone (O3). Daily incident cases of TB were obtained from the Hubei Provincial Center for Disease Control and Prevention (Hubei CDC). Both single- and multiple-pollutant models were used to examine the associations between air pollution and TB. Seasonal variation was assessed by splitting the all-year data into warm (May–October) and cold (November–April) seasons. In the single-pollutant model, for a 10 μg/m3 increase in PM2.5, PM10, and O3 at lag 7, the associated TB risk increased by 17.03% (95% CI: 6.39, 28.74), 11.08% (95% CI: 6.39, 28.74), and 16.15% (95% CI: 1.88, 32.42), respectively. In the multi-pollutant model, the effect of PM2.5 on TB remained statistically significant, while the effects of other pollutants were attenuated. The seasonal analysis showed that there was not much difference regarding the impact of air pollution on TB between the warm season and the cold season. Our study reveals that the mechanism linking air pollution and TB is still complex. Further research is warranted to explore the interaction of air pollution and TB.


2020 ◽  
Vol 4 (2) ◽  
pp. 50-61
Author(s):  
Lekhmissi LOUAR

The aim of this study is to measure the impact of the policy of supporting short-term loans on agricultural production through the use of the Panel-Data model for the period 2009-2015 on a sample consisting of 6 constituencies of Oum El Bouaghi State. This is after testing the model of fixed effects which was considered the ideal model for the study. The results showed that a joint integration relationship between support for short-term loans and agricultural production in the state of Oum El Bouaghi was detected in the short term. This positive impact confirms the success of the policy of supporting short-term agricultural loans as having a zero-interest rate


2000 ◽  
Vol 40 (2) ◽  
pp. 343 ◽  
Author(s):  
D. R. Kemp ◽  
D. L. Michalk ◽  
J. M. Virgona

The Temperate Pasture Sustainability Key Program (TPSKP) was established across south-eastern Australia to test the hypotheses that an improved perennial grass content in pastures would result in fewer weeds, better water use (and hence lesser impacts on soil salinity), and lower soil acidification rates. Grazing tactics were seen as a means to enhance or maintain the perennial grass content. Soil and water sustainability experiments in summer and winter dominant rainfall environments showed fewer weeds, improvements in water use and less acidity under perennial versus annual grass pastures. Further work is needed to determine if these gains are sufficient to make perennial grass pastures sustainable in the long-term as some nitrate leakage still occurred at the winter rainfall site. Indicators were developed to rate the sustainability of treatments within experiments. A subset of these indicators was common across experiments and could readily be used by farmers to provide an initial assessment of the soil and water sustainability of their pasture systems. These are: the mineral nitrogen at the bottom of the root zone (40–60 cm); soil pH at the surface and bottom of the root zone and perennial grass content by species. Managing pastures through droughts is a critical aspect of grazing management in Australia. Experiments within the TPSKP demonstrated that perennial grasses survived during drought when maintained above critical lower biomass values. These values ranged from 0.5 to 1.5 t DM/ha depending upon species. Over all experiments, there was general support for the view that maintaining a higher level of biomass in pastures resulted in more sustainable systems. Twenty-three grazing experiments using an open communal grazing design showed that most perennial grasses were sensitive to grazing at some stage in their seasonal growth cycles. The exceptions were inconclusive for several reasons e.g. the grazing pressure may not have been high enough at those sites to elucidate any effects; they occurred where the perennial grass content was less than 10% or exceeded 70%, of the sward; or were confounded by interactions between species where the species under study was not dominant. After taking these exceptions into account, it was then possible to determine where grazing tactics could be expected to work. Species differed in their response to grazing. Some perennial grasses were more sensitive to grazing during periods of stress (e.g. dry summers) than when actively growing (e.g. cocksfoot), while the reverse applied with others (e.g. phalaris). Of the grasses sensitive to grazing when actively growing, sensitivity of some was largely confined to the reproductive period (e.g. perennial ryegrass). Across most experiments, continuous grazing resulted in either a decline in or no net benefit to, the perennial grass content. Microlaena stipoides was the only species to respond to increased grazing pressure — this only applied in spring. The experiments clearly showed that tactical rests were an important tool for grassland management. The effects recorded were predominantly expressed through impacts on vegetative growth and survival of existing plants. Short-term experiments and dry seasons did not enable recruitment processes to be studied. Within pastures, grazing tactics can influence many species. The challenge is to use the TPSKP outcomes to develop strategies that optimise the composition of these swards. Due to the short-term nature of these experiments the results were evaluated within a conservative framework and often simply on the absolute level of parameters. Techniques need to be developed to more effectively monitor the process (i.e. rates of change), rather than the consequences (i.e. ends). The information gained in this program needs to be incorporated into practical strategies for better management of pastures and tested at a commercial scale. The TPSKP was one of the largest, coordinated pasture programs ever attempted. Some major outcomes were the experience gained by a large number of grassland scientists in running such programs, the development and acceptance of standardised measurement protocols and a much stronger network among grazing systems scientists committed to achieving improved management systems.


2011 ◽  
Vol 347-353 ◽  
pp. 10-15
Author(s):  
Li Hong Wang ◽  
Bao Guo Wang ◽  
Gui Feng Liu ◽  
Zhi Hong Tian

This paper analyzes the impact of the rise and decline of the oil prices on the agricultural diesel prices, and interviews the reasons and effects. The results show that the rise of the oil price is the major factor that impacts on diesel price change, that is to say, the price of diesel oil price goes up with the rise of oil price, however, it does not fall with the decline of oil price in short term. Possible explanations for these results are offered. The most important one is that the monopoly market structure of agricultural diesel and oil is the main reason why the agricultural diesel price responds asymmetrically to oil price change. And it gives some advice to find out a way to cope with the inconsistency between agricultural production and the oil price.


Author(s):  
Florian Arendt

A test was done to see if reading a newspaper which consistently overrepresents foreigners as criminals strengthens the automatic association between foreign country and criminal in memory (i.e., implicit cultivation). Further, an investigation was done to find out if reading articles from the same newspaper produces a short-term effect on the same measure and if (1) emotionalization of the newspaper texts, (2) emotional reactions of the reader (indicated by arousal), and (3) attributed text credibility moderate the short-term treatment effect. Eighty-five participants were assigned to one of three experimental conditions. Participants in the control group received short factual crime texts, where the nationality of the offender was not mentioned. Participants in the factual treatment group received the same texts, but the foreign nationality was mentioned. Participants in the emotionalized treatment group received emotionalized articles (i.e., texts which are high in vividness and frequency) covering the same crimes, with the foreign nationality mentioned. Supporting empirical evidence for implicit cultivation and a short-term effect was found. However, only emotionalized articles produced a short-term effect on the strength of the automatic association, indicating that newspaper texts must have a minimum of stimulus intensity to overcome an effect threshold. There were no moderating effects of arousal or credibility pertaining to the impact on the implicit measure. However, credibility moderated the short-term effect on a first-order judgment (i.e., estimated frequency of foreigners of all criminals). This indicates that a newspaper’s effect on the strength of automatic associations is relatively independent from processes of propositional reasoning.


2019 ◽  
Vol 5 (5) ◽  
pp. 550-562

Drawn upon field research in two peri-urban villages of Hanoi in 2014 and short re-visits recently, the research examines the widespread of gambling and other social issues in Hanoi’s urbanizing peri-urban communities which happened concurrently with the phenomenon of “land fever,” and at the time local villagers received compensation from land appropriation. The article aims to understand the impact of urbanization on these communities and the interface between urbanization and the increase of social problems. It argues that gambling, drug use, and other social problems have been existing in Vietnamese rural communities long before; however, when urbanization came, some people have higher chances to engage in these activities. Those are villagers who want to transform quickly into entrepreneurs or bosses by joining the “black credit” market and gambling. Together with middle-aged and old farmers who greatly relied on agricultural production and face difficulties in transforming their occupation, they formed the group of losers in the urbanization process. Received 6th January 2019; Revised 26th April 2019; Accepted 15th May 2019


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