Agroforestry management, seasonal changes, biodiversity and multitrophic interactions of coffee arthropods dissertation to obtain the ph. From the mid1950s to 1986, almost 69 million acres of natural habitat was converted to urban or suburban areas grey and deneke, 1986. Effect of agroecosystem diversity on natural enemies of. Tree diversity drives diversity of arthropod herbivores, but. Previous agricultural research has shown that crop rotation and the use of cover crops can lead to increases in yield relative to monoculture. Plant diversity drives global patterns of insect invasions. In contrast, and despite substantial variation among mahogany maternal families in growth, chemical defenses, and herbivore resistance 47, 63, we did not find effects of genotypic diversity on ants or herbivores. With a growing world population and increasingly demanding consumers, the production of sufficient protein from livestock, poultry, and fish represents a. Whereas the plants on a typical green roof are chosen and planted by. Vegetational diversity and arthropod population response. Intensified agriculture favors evolved resistance to. Genome regulation and the generation of phenotypic diversity.
Animal diversity arthropods clades questions and study. We studied the effects of plant genotypic diversity of tall goldenrod solidago altissima on the population dynamics of the aphid uroleucon. Vegetational diversity and density in agroecosystems may influence the abundance of herbivorous insects and their natural enemies andow 1983. Four habitat types were compared that comprise the majority 84.
Biodiversity is the degree of variation of genetic variation, ecosystem variation, or species variation number of species 1 within an area, biome, or planet. In this study, we investigated how agroforestry management affects the population dynamics of three major arthropod coffee pests, namely, spider mites, leaf miners and berry borers over an entire year in a coffeegrowing region in ecuador. Arthropod developmental stages may differ in their responses to agroecosystem management. Oct 12, 2016 the performance and population dynamics of insect herbivores depend on the nutritive and defensive traits of their host plants1. Among other factors, the diversity of all living things depends on temperature, precipitation, altitude, soils, geography and the presence of other species. Animal diversity arthropods clades questions and study guide. Therefore, the diversity of cultivated plants and arthropod communities was assessed within tomato fields from 30 farmers fields randomly selected in south of benin. Roles of food quality and enemy free space in host use by a generalist insect herbivore. Intercropping impacts the host location behaviour and. Total arthropod species richness in a 6,000 ha tropical rainforest, estimated at 25,000 species, can be best predicted by plant diversity.
Diversity of arthropod community in transgenic poplarcotton ecosystems d. The misconception persists that crop diversity in itself reduces pest damage. Overall, these results indicate the dominance of plant diversity as a driver of insect invasions. Recent studies have investigated the relationships between plant diversity and arthropod communities at the landscape scale, but few have done so at the local scale.
We report results of a direct experimental test of the dependence of animal diversity on plant diversity. Our results suggest that arthropod diversity in a subtropical forest reflects the. The weak response of predators to tree species richness may indicate. Factors influencing arthropod diversity on green roofs. Andow da 1991 vegetational diversity and arthropod. Various techniques to restore agricultural diversity in time and space include crop rotations, cover. Altieri division of biological control, university of california berkeley, 1050 san pablo avenue, albany, ca 94706, usa i.
Experimental tests of the dependence of arthropod diversity. Plant genotypic diversity increases population size of a. Population responses by orius insidiosus to vegetational diversity. Vegetational diversity and arthopod population response. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Plant diversity is a major determinant of arthropod diversity in grasslands siemann 1997, siemann et al. The study of the spatial distribution of organisms, species and ecosystems, is the science of biogeography. Prospects for ecological engineering for planthoppers and other. Results the population densities of wheat aphid, coccinelids and syrphid fly were significantly varied among all treatments table i. A second hypothesis explaining the nonadditive effects on population size would be the effects of natural enemies. It is critical to incorporate the process of population dynamics into community genetics studies to identify the mechanisms of the linkage between host plant genetics and associated communities.
Ecological mechanisms underlying arthropod species diversity. More than 3540% of the worlds forests and other natural ice free habitats have been converted to cropland and pasture. The resource concentration hypothesis is a testable, herbivory. Approximately 1,900 insect species are eaten worldwide, mainly in. Effect of plant diversification on abundance of south american. Aug 01, 2004 aphid response to vegetation diversity and insecticide applications aphid response to vegetation diversity and insecticide applications banks, j. Associated cultivated plants in tomato cropping systems. The direction and magnitude of the response of different arthropod taxa to grazing management reflects their trophic level, life history, size and mobility, e.
Relationships between plant diversity and the abundance. Evaluation of arthropod diversity and abundance in. However, the longterm viability of this ecosystem service can be threatened by the expansion and simplification of agricultural. Genetic diversity serves as a way for populations to adapt to changing environments. Are tree species diversity and genotypic diversity effects on. Plant genotypic diversity reduces the rate of consumer resource utilization, proceedings of the royal society b. Recent studies have investigated the relationships between plant diversity and arthropod communities at the landscape. Laws division of biology, kansas state university, manhattan, kansas 66506. Survey of diversity and abundance of grounddwelling.
The influence of vegetational diversity on the population ecology of. Effect of a nonhost plant on the location behavior of two. Disentangling the effects of plant diversity on the control of herbivores is important for understanding agricultural sustainability. Andow and others published vegetational diversity and arthropod population response find, read and cite all the research you need on researchgate. The influence of vegetational diversity on the population ecology of a specialized herbivore, phyllotreta cruciferae coleoptera. Resource dilution effects on specialist insect herbivores in. Diversity of arthropod community in transgenic poplar. The need for agricultural production to meet the food demands of a growing human population will require sustainable and acceptable pest management, such as biological control, across 11% 1.
The central theme of disturbance and the influence of vegetational diversity. In order to explore a possible relationship between aphid population growth and plant sap quality when intercropped, we analysed the concentration of free amino acids in leaves of the non. With more variation, it is more likely that some individuals in a population will possess. To describe differences in arthropod communities in response to urbanization, we report seven years of monitoring of arthropods in and surrounding phoenix, az. Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species. Jan 19, 2005 the resource concentration hypothesis is a testable, herbivory. It is distinguished from genetic variability, which describes the tendency of genetic characteristics to vary genetic diversity serves as a way for populations to adapt to changing environments. Sensitivity of upland arthropod diversity to livestock grazing, vegetation structure and landform peter dennis macaulay institute, craigiebuckler, aberdeen, ab15 8qh, scotland, uk. Response of pest control by generalist predators to local. N2 contrasts mixed species plantings polycultures with bareground solecrop fields monocultures, the former being characterised by the simultaneous occurrence of herbivory with both inter and intraspecific plant competition, and where plants are.
Bison grazing also increased diversity for both herbivores and carnivores. Aphid response to vegetation diversity and insecticide. Vegetational diversity and arthropod population response annual. Population responses by orius insidiosus to vegetational. There was a significant positive correlation between faunal and floral diversity, with arthropod diversity lowest in the crop, low in the crop edge, higher in the more diverse sown plots and highest in the hedge. Galling arthropod diversity in adjacent swamp forests and. Results showed that the arthropod abundance was significantly higher in mixedcropping systems compared with monocropping systems, although the crop type did not alter.
Ecological mechanisms underlying arthropod species. Resource dilution effects on specialist insect herbivores. In contrast, suction sampling showed marked differences between the crop, the hedge and the plots with different vegetation structures. In temperate agri cultural settings, several experiments have demonstrated that crop systems grown with a high diversity of weeds i. As a result of the economic boom in the mid20th century, the middleclass changed its way of life, increasing urban sprawl due to movement away from city centers robbins and sharp, 2003a. Terrestrial biodiversity tends to be highest near the equator, 2 which seems to be the result of the warm climate and high primary productivity. Success in conservation biological control of arthropods.
Mar 15, 2008 understanding the role of diversity in the functioning of ecosystems has important implications for agriculture. Biodiversity project gutenberg selfpublishing ebooks. Abstract vegetational diversity within agricultural fields is often suggested as a means to reduce insect herbivore populations and to increase their natural enemies. Among other factors, the diversity of all living things ecosystems, is the science of biogeography diversity consistently measures higher in the tropics and in other localized regions such as the cape floristic region and lower in polar regions generally. Effects of crop diversity on agroecosystem function. This lends credence to global estimates of arthropod biodiversity developed from plant models. Pdf vegetational diversity and arthropod population.
The lower abundance of soil arthropod in anua community as compared to ekpri. T1 vegetational diversity and arthropod population response. Pdf vegetational diversity and arthropod population response. The influence of vegetational diversity on the population ecology of a. The performance and population dynamics of insect herbivores depend on the nutritive and defensive traits of their host plants1. Aphid response to vegetation diversity and insecticide applications aphid response to vegetation diversity and insecticide applications banks, j. Total abundance of arthropods decreased in 62% of studies and increased in 15%. Responsiveness of arthropod herbivores and their natural. One approach to understanding the effects of agricultural management on arthropod diversity is to consider management impacts. Anthocoridae and its prey were recorded in vegetationally diverse soybean and agronomic weeds and monoculture soybean only fields. Understanding the role of diversity in the functioning of ecosystems has important implications for agriculture. Arthropods were collected with pitfall traps in two alleycropped. N2 contrasts mixed species plantings polycultures with bareground solecrop fields monocultures, the former being characterised by the simultaneous occurrence of herbivory with both inter and intraspecific plant competition, and where plants are interspersed at.
A study was conducted at mtwapa in the northern coastal area of kenya during the long and short rainy seasons of 1999 and 2000 to assess the benefits of agroecosystem diversificationthrough agroforestry and intercroppingon the activity of natural enemies of maize stemborers. Abstract because a diversity of resources should support a diversity of consumers, most models predict that increasing plant diversity increases animal diversity. With a growing world population and increasingly demanding consumers, the production of sufficient protein from livestock, poultry, and fish represents a serious challenge for the future. Orius insidiosus adults and nymphs were more abundant in diversified plots than in monocultures. Factors influencing arthropod diversity on green roofs green roofs have potential for providing substantial habitat to plants, birds, and arthropod species that are not well supported by other urban habitats. Therefore, we conclude that sourcesink dynamics via shortdistance movement within a plot are likely to have caused the nonadditive increase in aphid population size in response to genotypic diversity of host plants. Arthropod abundance and diversity in differently vegetated. The influence of vegetational diversity on the population ecology of a specialized herbivore, phyllotreta cruciferae.
Population dynamics of aphids and their natural enemies. Plant diversity impacts on arthropod communities and. For example, morphological or behavioural concealment tends to promote tight linkage of population dynamics between the herbivore and. Biodiversity is not evenly distributed, rather it varies greatly across the globe as well as within regions. It is distinguished from genetic variability, which describes the tendency of genetic characteristics to vary. While direct competition plays a key role in plant community assembly. Vegetational diversity and arthropod population response vegetational diversity and arthropod population response andow, d a 19910101 00. Are tree species diversity and genotypic diversity effects. A positive relationship between plant diversity and both abundance and diversity of predatory arthropods is postulated by the enemies hypothesis, a central ecological topdown control hypothesis. Previous work has found positive effects plant genotypic diversity on arthropod abundance and diversity 8, 11. Hypothesized response of ecosystem function to decrease in species richness. Balancing disturbance and conservation in agroecosystems.
The abundance of different life stages of orius insidiosus say heteroptera. The obtained data for predators and aphid population were analyzed using anova with spss10. Ecological mechanisms underlying arthropod species diversity in grasslands anthony joern. Variability in plant nutrients reduces insect herbivore. It has been supported by experimental studies and investigations. Are the ecological concepts of assembly and function of. Arthropod abundance and diversity in differently vegetated margins of arable fields. Approximately 1,900 insect species are eaten worldwide. The results showed that observational dates varied meaningfully in response to coccinelid and syrphid fly species per plant whereas the variation among different treatments revealed slight difference in total capturing. Sensitivity of upland arthropod diversity to livestock. Dec 20, 20 values were calculated for the entire sampling period in 2011 and 2012 to minimize effects of interannual variations. Alley cropping is an integrated land management practice growing economic crops between rows of trees. This paper examines the effects of alley cropping on carabid beetles and other ground dwelling arthropod predators on species diversity and abundance by testing for differences among ground vegetation treatments in alleyways. Effect of agroecosystem diversity on natural enemies of maize.
247 525 871 1095 913 1052 411 330 1635 1511 679 380 1198 1354 1606 1154 758 1305 509 164 280 979 229 1309 1355 156 55 1448 115 543 1350