scholarly journals Habitat complexity in organic olive orchards modulates the abundance of natural enemies but not the attraction to plant species

2021 ◽  
Author(s):  
Hugo Alejandro Álvarez ◽  
Marina Morente ◽  
Francisca Ruano

AbstractSemi-natural habitat complexity and organic management could affect the abundance and diversity of natural enemies and pollinators in olive orchards. Nonetheless, in such agroecosystems the effect of plant structure, plant richness, and plant attraction on the arthropod fauna has been poorly documented. Here we evaluate the influence of those effects jointly as an expression of arthropod abundance and richness in olive trees, ground cover, and adjacent vegetation within organic olive orchards. For this, we used generalized linear models and non-metric multidimensional scaling (NMDS) integrating generalized additive models. Our results suggest that natural enemies and pollinators are mainly attracted to A. radiatus, D. catholica, and L. longirrostris within ground cover and G. cinerea speciosa, Q. rotundifolia, R. officinalis, T. zygis gracilis, and U. parviflorus within adjacent vegetation. Accordingly, habitat complexity showed a positive relationship with the abundance of key families of natural enemies and pollinators but not with the number of taxa. NMDS showed that plant richness and plant arrangement and scattering affected the key families differently, suggesting that each key family responds to their individual needs for plant resources but forming groups modulated by complexity. This pattern was especially seeing in predators and omnivores. Our findings support that the higher the plant richness and structure of a semi natural-habitat within an olive orchard, the higher the abundance and richness of a given arthropod community (a pattern found in natural ecosystems). The information presented here can be used by producers and technicians to increase the presence and abundance of natural enemies and pollinators within organic olive orchards, and thus improve the ecosystem services provided by semi-natural habitats.Graphical abstract

Social Change ◽  
2003 ◽  
Vol 33 (2-3) ◽  
pp. 204-221
Author(s):  
Ghazala Shahabuddin

During the last few decades, there has been a growing realisation that biodiversity conservation cannot be successful without the active involvement of the people living close to and dependent on natural ecosystems for their survival and livelihoods. Consequently, there has been a gradual broadening of the global conservation agenda from strict nature protection to include the sustainable use of natural resources, which is now reflected in governmental policy the world over. However, as conservationists strive today towards the harmonisation of people's needs with biodiversity conservation, one of the most elusive, yet critical, goals for them has been the sustainable extraction of plant resources from the wild. Hundreds of plant species continue to be extracted from natural habitats for use as food, medicine, fuel and fodder in households and for commercial sale, both legally and illegally. As a consequence of unmonitored extraction and over-exploitation, many plant species populations are reported to be declining in the wild. In the face of increasing pressure on forest resources, it has become more important than ever before to devise quantitative management policies for sustainable plant use so that both forests and the livelihoods of millions of rural people who are dependent on them, can be sustained. One of the major stumbling blocks for conservationists in developing countries, who are attempting to design and implement sustainable forest management systems, is the lack of information on the state-of-the-art in this field, especially that relating to field methods, data analysis, data recording and monitoring systems. In order to fill this lacuna, a comprehensive bibliography of studies undertaken so far in the science of sustainable use from terrestrial ecosystems is presented here. The scope of this bibliography includes sustainable


Author(s):  
Vladimir Grigor'ev ◽  
Dan Chuong Fam Thi ◽  
Rustam Nizamov ◽  
Igor' Grigor'ev

Aquaculture is one of the most promising and dynamically developing types of agricultural production, especially in countries with warm climates. The research was carried out to analyze the current situation in aquaculture in Vietnam to clarify the existing problems and prospects of this industry. When collecting materials, we used statistical data from the Government of the Socialist Republic of Vietnam, as well as information from representatives of the Institute of Economics and Business of the Vietnam National University (Hanoi). In the Socialist Republic of Vietnam, aquaculture is well developed and continues to actively expand, annually increasing the production of products that are in significant demand on the world market. One of the most important problems of the industry is the threat to natural biodiversity, primarily due to the reduction of the natural habitats of the inhabitants of rivers and mangroves. An equally important problem is the strong dependence of the production of products, primarily shrimp, on foreign markets, which today is objective and insurmountable. Due to the use of chemicals and antibiotics in aquaculture, especially in natural conditions, environmental degradation is possible. Among the promising areas for the development of the industry is the convergence of natural ecosystems and agriculture, a good example of which is the cultivation of shrimp in mangroves without destroying the forest cover. It is possible to switch to aquaculture as an adaptation to changes in the ecological situation, primarily to the salinization of river deltas. As a result of a decrease in the profitability of fishing in the natural habitat of fish and shrimps, an increase in their populations in natural conditions is possible


2018 ◽  
Vol 18 (1) ◽  
pp. 75
Author(s):  
Akhmad Rizali ◽  
Toto Himawan ◽  
Ima Fitriani ◽  
Bambang Tri Rahardjo ◽  
Sri Karindah ◽  
...  

Effect of Natural Habitat on Diversity of Hemipteran Predator in Oil Palm Plantation. Utillization of natural enemies in controlling oil palm pests still encounters obstacles, in particular, how natural enemies can survive and establish in oil palm plantations. The existence of natural habitats around oil palm plantations can allegedly support the occurence of natural enemies. The objective of this study was to investigate the effect of the presence of natural habitats on diversity of hemipteran predators in oil palm plantations. Field research was conducted in oil palm plantations located in Pangkalan Bun, Central Kalimantan. The plots were oil palm plantations with different distances from natural habitat i.e. near (less than 200 m), medium (about 2 km) and far (about 5 km). Each plot was selected six trees for fogging using insecticide with active ingredient lamda cyhalothrin. Based on research result, diversity of hemipteran predator in oil palm plantion was found 19 species belong to 2 families. The most dominant hemipteran predator was Sycanus sp., Eocanthecona sp. and Reduviidae sp5. The distance of oil palm plantation from natural habitat did not affect species richness, abundance and composition as well as recolonization of hemipteran predator in oil palm plantation. Abundance of hemipteran predator tend to decrease in different observation time, except Sycanus sp. Sycanus sp was likely has ability to rapidly recolonized and their occurrence were influenced by flowering vegetation in oil palm plantation.


2019 ◽  
Vol 285 ◽  
pp. 106618 ◽  
Author(s):  
Hugo Alejandro Álvarez ◽  
Marina Morente ◽  
F. Shigeo Oi ◽  
Estefanía Rodríguez ◽  
Mercedes Campos ◽  
...  

2015 ◽  
Vol 105 (3) ◽  
pp. 261-272 ◽  
Author(s):  
R.A. King ◽  
W.O.C. Symondson ◽  
R.J. Thomas

AbstractWild habitats adjoining farmland are potentially valuable sources of natural enemies, but also of pests. Here we tested the utility of birds as ‘sampling devices’, to identify the diversity of prey available to predators and particularly to screen for pests and natural enemies using natural ecosystems as refugia. Here we used PCR to amplify prey DNA from three sympatric songbirds foraging on small invertebrates in Phragmites reedbed ecosystems, namely the Reed Warbler (Acrocephalus scirpaceus), Sedge Warbler (Acrocephalus schoenobaenus) and Cetti's Warbler (Cettia cetti). A recently described general invertebrate primer pair was used for the first time to analyse diets. Amplicons were cloned and sequenced, then identified by reference to the Barcoding of Life Database and to our own sequences obtained from fresh invertebrates. Forty-five distinct prey DNA sequences were obtained from 11 faecal samples, of which 39 could be identified to species or genus. Targeting three warbler species ensured that species-specific differences in prey choice broadened the range of prey taken. Amongst the prey found in reedbeds were major pests (including the tomato moth Lacanobia oleracea) as well as many potentially valuable natural enemies including aphidophagous hoverflies and braconid wasps. Given the mobility of birds, this approach provides a practical way of sampling a whole habitat at once, providing growers with information on possible invasion by locally resident pests and the colonization potential of natural enemies from local natural habitats.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Cheng Gong ◽  
Liangtao Li ◽  
Jan C. Axmarcher ◽  
Zhenrong Yu ◽  
Yunhui Liu

AbstractIn the intensively farmed, homogenous agricultural landscape of the North China Plain, family graveyards form distinct cultural landscape features. In addition to their cultural value, these graveyards represent semi-natural habitat islands whose potential roles in biodiversity conservation and ecological functioning has remained poorly understood. In this study, we investigated plant species richness on 199 family graveyards of different ages and sizes. In accordance with biogeography theory, both overall and insect-pollinated plant species richness increased with area and age of graveyards. Even small graveyards show a strong potential for conserving local plant richness, and a mosaic of both large and small family graveyards could play an important role in the conservation of farmland biodiversity and related ecosystem functions. The launch of agri-environmental measures that conserve and create semi-natural habitats, in turn benefitting agricultural biodiversity and ecological functioning, has proven difficult in China due to the shortage of dispensable arable land. Given the great value of family graveyards as semi-natural habitats reflected in our study, we propose to focus preliminary efforts on conserving these landscape features as existing, widespread and culturally important semi-natural habitat islands. This would represent an effective, complementary policy to a subsequent re-establishment of other semi-natural habitats for the conservation of biodiversity and ecological functioning in agricultural landscapes.


1983 ◽  
Vol 31 (5) ◽  
pp. 695 ◽  
Author(s):  
IJ Rooke ◽  
SD Bradshaw ◽  
RA Langworthy

Total body water content (TBW) and TBW turnover were measured by means of tritiated water (HTO) in free-ranging populations of silvereyes, Zosterops lateralis, near Margaret River, W.A. Birds were studied in their natural habitats during spring and summer, and compared with a vineyard population in summer. In the natural habitat TBW content was found to be 77.6% in spring, which was not significantly different from that measured in summer (78.3%). Birds in vineyards in summer, however, were dehydrated, with a TBW content of 69.4%. Calculated rates of water influx for spring, summer and summer vineyards birds were 1.44,2.20 and 0.65 ml g.day-' respectively. These water turnover rates are much higher than those of any other bird yet studied. Dehydration was marked in the vineyard birds, with a significantly lower TBW content and an average net water loss of 0.63 ml day-'. Laboratory studies showed that silvereyes have a low tolerance to sodium loading. Their tolerance is, however, quite adequate for them to drink the most concentrated free water available to them in the field. Ingestion of concentrated sugar solutions of up to 25% did not provoke an osmotic diuresis and thus cannot account for the dehydration and negative water balance of vineyard birds.


2021 ◽  
Vol 14 (2) ◽  
pp. 2-15
Author(s):  
L. A. Arepieva ◽  
E. I. Arepiev ◽  
S. G. Kazakov

The distribution of the Sosnovsky hogweed on the southern border of the secondary range in the European part of Russia on the example of the Kursk Region is investigated in the work. It is revealed that Sosnovsky hogweed grows mainly in the western part of the Region in the vicinity of places where it was cultivated in fields in the second half of the twentieth century. The analysis of invader occurrence in anthropogenic and natural ecosystems of the Region revealed patterns of distribution that are characteristic of invasive species at initial stages of their secondary range formation: most of the foci are present in anthropogenic and semi-natural habitats; medium-sized foci predominate (from 100 sq. m. to 1 ha); the greatest number of foci was found in the areas located along roads. The intensive distribution of hogweed in settlements of the Region, especially with pronounced depopulation processes, was revealed. Among natural and semi-natural habitats, most of the foci were found along the banks of reservoirs. In forests, hogweed is found mainly in small groups of vegetative rosettes on the outskirts, with the exception of areas with a strong anthropogenic impact, where multiple foci with generative shoots are formed. At present, hogweed is not found on arable land due to the intensive cultivation of agricultural land in the Region. Plant communities with Heracleum sosnowskyi in the Kursk Region are represented by 4 syntaxons: association Urtico dioicae-Heracleetum sosnowskyi , association Rudbeckio laciniatae - Solidaginetum canadensis variant Heracleum sosnowskyi , association Chelidonio-Aceretum negundi variant Heracleum sosnowskyi , derivative community Heracleum sosnowskyi [ Agropyretalia intermedio-repentis ].


2012 ◽  
Vol 26 (4) ◽  
pp. 735-747 ◽  
Author(s):  
Mariana Reis de Brito ◽  
Luci de Senna-Valle

The number of publications about the Caiçaras population is growing, which shows that researchers are interested in these natives. This study aimed to survey the flora used by local specialists of the Praia do Sono Caiçara community, and recorded how these taxa were used, with the goal of understanding traditional management systems that help to conserve natural ecosystems. Twelve informants were selected and interviewed. The applied grouping analysis, together with the chi-squared test, underlined that the analysed ethnobotanical knowledge showed a heterogeneous distribution in relation to the gender of the interviewee. A total of 190 taxa were cited and were classified into nine usage categories. The Shannon-Wiener index (H') value obtained in this study was the second highest in comparison to other Brazilian coastal communities. This work showed that the local specialists of this Caiçara community maintain a wide knowledge of, and affinity to, the plant resources that surround them. This knowledge is not only important, but fundamental to discussions about the application of sustainable use and management strategies for this area of conservation value.


2015 ◽  
Vol 10 (4) ◽  
pp. 215 ◽  
Author(s):  
Roberta Rossi ◽  
Alessio Pollice ◽  
Gianfranco Bitella ◽  
Rocco Bochicchio ◽  
Amedeo D'Antonio ◽  
...  

Alfalfa is a highly productive and fertility-building forage crop; its performance, can be highly variable as influenced by within-field soil spatial variability. Characterising the relations between soil and forage- variation is important for optimal management. The aim of this work was to model the relationship between soil electrical resistivity (ER) and plant productivity in an alfalfa (<em>Medicago sativa</em> L.) field in Southern Italy. ER mapping was accomplished by a multi-depth automatic resistivity profiler. Plant productivity was assessed through normalised difference vegetation index (NDVI) at 2 dates. A non-linear relationship between NDVI and deep soil ER was modelled within the framework of generalised additive models. The best model explained 70% of the total variability. Soil profiles at six locations selected along a gradient of ER showed differences related to texture (ranging from clay to sandy-clay loam), gravel content (0 to 55%) and to the presence of a petrocalcic horizon. Our results prove that multi-depth ER can be used to localise permanent soil features that drive plant productivity.


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