Agricultural Intensification and Pest Outbreaks: A Reappraisal of Events in the Sudan Gezira

Disturbances associated with agricultural intensification reduce our ability to achieve sustainable crop production. These disturbances stem from crop-management tactics and can leave crop fields more vulnerable to insect outbreaks, in part because natural-enemy communities often tend to be more susceptible to disturbance than herbivorous pests. Recent research has explored practices that conserve natural-enemy communities and reduce pest outbreaks, revealing that different components of agroecosystems can influence natural-enemy populations. In this review, we consider a range of disturbances that influence pest control provided by natural enemies and how conservation practices can mitigate or counteract disturbance. We use four case studies to illustrate how conservation and disturbance mitigation increase the potential for biological control and provide co-benefits for the broader agroecosystem. To facilitate the adoption of conservation practices that improve top-down control across significant areas of the landscape, these practices will need to provide multifunctional benefits, but should be implemented with natural enemies explicitly in mind.

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Cattle, Sheep/Goats and Pigs from Northern and Central Hampshire: Iron Age, Roman and Early Saxon Faunal Remains from Excavation Assemblages

Hampshire Studies ◽

10.24202/hs2020016 ◽

2020 ◽

Vol 75 (1) ◽

pp. 255-272

Author(s):

Anthony C. King

Keyword(s):

Iron Age ◽

Agricultural Intensification ◽

Animal Husbandry ◽

Faunal Remains ◽

Wool Production ◽

Animal Economy

This paper is a survey of overall species counts from northern and central Hampshire sites, of Iron Age, Roman and early Saxon date, and their implications for chronological changes in animal husbandry and diet. Three zones, around Basingstoke, Andover, and central Hampshire, are compared with each other, and also with the Roman urban centres of Silchester and Winchester. The Andover region shows the greatest degree of continuity from Iron Age to Roman times and later, while the Basingstoke region has a pattern of change from sheep/goat dominated assemblages to ones with higher cattle numbers. This may be due to agricultural intensification, and an orientation of the animal economy in northern Hampshire more towards the Thames Valley and supply to Silchester, than an earlier 'Wessex pattern' more focussed on sheep and wool production.

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Agricultural intensification and fertilizer use

10.2499/9780896298811_05 ◽

2016 ◽

Cited By ~ 1

Author(s):

International Food Policy Research Institute (IFPRI)

Keyword(s):

Agricultural Intensification ◽

Fertilizer Use

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Seaweed aquaculture: a preliminary assessment of biosecurity measures for controlling the ice-ice syndrome and pest outbreaks of a Kappaphycus farm

Journal of Applied Phycology ◽

10.1007/s10811-021-02530-z ◽

2021 ◽

Author(s):

Cicilia S. B. Kambey ◽

Iona Campbell ◽

Elizabeth J. Cottier-Cook ◽

Adibi R. M. Nor ◽

Azhar Kassim ◽

...

Keyword(s):

Hazard Analysis ◽

Kappaphycus Alvarezii ◽

Control Point ◽

Control Measures ◽

Seaweed Aquaculture ◽

Critical Control Point ◽

Management Measures ◽

Long Line ◽

Pest Outbreaks ◽

The Impact

AbstractThe application of biosecurity in seaweed aquaculture plays an important role in reducing the impact of disease and pest outbreaks. The continuous occurrence of seaweed pests including the macroalgal epiphytes, epi-endophytic filamentous algae and biofilms on Kappaphycus farms may also potentially induce further incidences of the ice-ice syndrome. In this study, on-farm biosecurity management measures were tested on the commercially grown seaweeds Kappaphycus malesianus and Kappaphycus alvarezii during peak ice-ice season at Gallam-Gallam Village, Sabah, Malaysia. The investigation was focused on preventative control measures including the early detection of the ice-ice syndrome and pests through propagule health checks, regular cleaning of the crop thallus and associated long-line ropes and monitoring of the environment. Farm procedures and practices were also assessed in terms of their biosecurity ‘risk’ using the hazard analysis and critical control point (HCCAP) approach. Observations were replicated in two different farm management systems; one system adopted routine biosecurity measures and the other had no biosecurity measures. The results showed that the ice-ice syndrome and pest outbreak was significantly decreased by 60–75% for K. malesianus and 29–71% for K. alvarezii at the farm which adopted the routine biosecurity measures compared with the no biosecurity treatment. The biosecurity measures also significantly improved growth rate and seaweed quality. The infection levels of the epi-endophyte Melanothamnus sp. contributed to the ice-ice syndrome in K. malesianus, whilst the epiphyte coverage was correlated to the ice-ice incidence in K. alvarezii. This study provides the first evidence of biosecurity management measures significantly decreasing the incidence of the ice-ice syndrome and pests on a commercial seaweed farm.

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Does agricultural intensification cause tipping points in ecosystem services?

Landscape Ecology ◽

10.1007/s10980-021-01321-8 ◽

2021 ◽

Author(s):

Stephen C. L. Watson ◽

Adrian C. Newton ◽

Lucy E. Ridding ◽

Paul M. Evans ◽

Steven Brand ◽

...

Keyword(s):

Ecosystem Services ◽

Agricultural Intensification ◽

Spatial Dynamics ◽

Policy Option ◽

List Type ◽

Tipping Points ◽

Software Models ◽

Non Linear ◽

Study Interval ◽

The Impact

Abstract Context Agricultural intensification is being widely pursued as a policy option to improve food security and human development. Yet, there is a need to understand the impact of agricultural intensification on the provision of multiple ecosystem services, and to evaluate the possible occurrence of tipping points. Objectives To quantify and assess the long-term spatial dynamics of ecosystem service (ES) provision in a landscape undergoing agricultural intensification at four time points 1930, 1950, 1980 and 2015. Determine if thresholds or tipping points in ES provision may have occurred and if there are any detectable impacts on economic development and employment. Methods We used the InVEST suite of software models together with a time series of historical land cover maps and an Input–Output model to evaluate these dynamics over an 85-year period in the county of Dorset, southern England. Results Results indicated that trends in ES were often non-linear, highlighting the potential for abrupt changes in ES provision to occur in response to slight changes in underlying drivers. Despite the fluctuations in provision of different ES, overall economic activity increased almost linearly during the study interval, in line with the increase in agricultural productivity. Conclusions Such non-linear thresholds in ES will need to be avoided in the future by approaches aiming to deliver sustainable agricultural intensification. A number of positive feedback mechanisms are identified that suggest these thresholds could be considered as tipping points. However, further research into these feedbacks is required to fully determine the occurrence of tipping points in agricultural systems.

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Secondary Forests and Agrarian Transitions: Insights from Nepal and Peru

Human Ecology ◽

10.1007/s10745-021-00224-1 ◽

2021 ◽

Author(s):

Adam Pain ◽

Kristina Marquardt ◽

Dil Khatri

Keyword(s):

Forest Regeneration ◽

Agricultural Intensification ◽

Necessary Conditions ◽

Secondary Forest ◽

Social Groups ◽

Agrarian Change ◽

Secondary Forests ◽

Land Access ◽

San Martín

AbstractWe provide an analytical contrast of the dynamics of secondary forest regeneration in Nepal and Peru framed by a set of common themes: land access, boundaries, territories, and rights, seemingly more secure in Nepal than Peru; processes of agrarian change and their consequences for forest-agriculture interactions and the role of secondary forest in the landscape, more marked in Peru, where San Martín is experiencing apparent agricultural intensification, than in Nepal; and finally processes of social differentiation that have consequences for different social groups, livelihood construction and their engagement with trees, common to both countries. These themes address the broader issue of the necessary conditions for secondary forest regeneration and the extent to which the rights and livelihood benefits of those actively managing it are secured.

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Rock removal associated with agricultural intensification will exacerbate loss of reptile diversity

Journal of Applied Ecology ◽

10.1111/1365-2664.13897 ◽

2021 ◽

Author(s):

Damian R. Michael ◽

Harry Moore ◽

Skye Wassens ◽

Michael D. Craig ◽

Reid Tingley ◽

...

Keyword(s):

Agricultural Intensification

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Framing agricultural intensification in western Iberia during the Late Neolithic: A new insight through the faunal record from Los Barruecos site

Journal of Archaeological Science Reports ◽

10.1016/j.jasrep.2021.102815 ◽

2021 ◽

Vol 36 ◽

pp. 102815

Author(s):

Nelson J. Almeida ◽

Enrique Cerrillo-Cuenca ◽

Palmira Saladié

Keyword(s):

Agricultural Intensification ◽

Late Neolithic

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Evaluating the Impact of Two Generalist Predators on the Leafhopper Erasmoneura vulnerata Population Density

Insects ◽

10.3390/insects12040321 ◽

2021 ◽

Vol 12 (4) ◽

pp. 321

Author(s):

Stefan Cristian Prazaru ◽

Giulia Zanettin ◽

Alberto Pozzebon ◽

Paola Tirello ◽

Francesco Toffoletto ◽

...

Keyword(s):

Field Experiments ◽

Field Studies ◽

Generalist Predators ◽

Predator Species ◽

Potted Plants ◽

Naturally Occurring ◽

Orius Majusculus ◽

Limited Effectiveness ◽

Pest Outbreaks ◽

The Impact

Outbreaks of the Nearctic leafhopper Erasmoneura vulnerata represent a threat to vinegrowers in Southern Europe, in particular in North-eastern Italy. The pest outbreaks are frequent in organic vineyards because insecticides labeled for organic viticulture show limited effectiveness towards leafhoppers. On the other hand, the naturally occurring predators and parasitoids of E. vulnerata in vineyards are often not able to keep leafhopper densities at acceptable levels for vine-growers. In this study, we evaluated the potential of two generalist, commercially available predators, Chrysoperla carnea and Orius majusculus, in suppressing E. vulnerata. Laboratory and semi-field experiments were carried out to evaluate both species’ predation capacity on E. vulnerata nymphs. The experiments were conducted on grapevine leaves inside Petri dishes (laboratory) and on potted and caged grapevines (semi-field); in both experiments, the leaves or potted plants were infested with E. vulnerata nymphs prior to predator releases. Both predator species exhibited a remarkable voracity and significantly reduced leafhopper densities in laboratory and semi-field experiments. Therefore, field studies were carried out over two growing seasons in two vineyards. We released 4 O. majusculus adults and 30 C. carnea larvae per m2 of canopy. Predator releases in vineyards reduced leafhopper densities by about 30% compared to the control plots. Results obtained in this study showed that the two predators have a potential to suppress the pest density, but more research is required to define appropriate predator–prey release ratios and release timing. Studies on intraguild interactions and competition with naturally occurring predators are also suggested.

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