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1.
J Environ Manage ; 275: 111132, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33002703

RESUMO

Local regulations on residential landscapes (yards and gardens) can facilitate or constrain ecosystem services and disservices in cities. To our knowledge, no studies have undertaken a comprehensive look at how municipalities regulate residential landscapes to achieve particular goals and to control management practices. Across six U.S. cities, we analyzed 156 municipal ordinances to examine regional patterns in local landscape regulations and their implications for sustainability. Specifically, we conducted content analysis to capture regulations aimed at: 1) goals pertaining to conservation and environmental management, aesthetics and nuisance avoidance, and health and wellbeing, and 2) management actions including vegetation maintenance, water and waste management, food production, and chemical inputs. Our results reveal significant variation in local and regional regulations. While regulatory goals stress stormwater management and nuisance avoidance, relatively few municipalities explicitly regulate residential yards to maintain property values, mitigate heat, or avoid allergens. Meanwhile, biological conservation and water quality protection are common goals, yet regulations on yard management practices (e.g., non-native plants or chemical inputs) sometimes contradict these purposes. In addition, regulations emphasizing aesthetics and the maintenance of vegetation, mowing of grass and weeds, as well as the removal of dead wood, may inhibit wildlife-friendly yards. As a whole, landscaping ordinances largely ignore tradeoffs between interacting goals and outcomes, thereby limiting their potential to support landscape sustainability. Recommendations therefore include coordinated, multiobjective planning through partnerships among planners, developers, researchers, and non-government entities at multiple scales.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Cidades , Jardinagem , Plantas
2.
Oecologia ; 194(1-2): 237-250, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33009940

RESUMO

Climate change causes species range expansions to higher latitudes and altitudes. It is expected that, due to differences in dispersal abilities between plants and soil biota, range-expanding plant species will become associated with a partly new belowground community in their expanded range. Theory on biological invasions predicts that outside their native range, range-expanding plant species may be released from specialist natural enemies, leading to the evolution of enhanced defence against generalist enemies. Here we tested the hypothesis that expanded range populations of the range-expanding plant species Centaurea stoebe accumulate fewer root-feeding nematodes than populations from the original range. Moreover, we examined whether Centaurea stoebe accumulates fewer root-feeding nematodes in expanded range soil than in original range soil. We grew plants from three expanded range and three original range populations of C. stoebe in soil from the original and from the new range. We compared nematode communities of C. stoebe with those of C. jacea, a congeneric species native to both ranges. Our results show that expanded range populations of C. stoebe did not accumulate fewer root-feeding nematodes than populations from the original range, but that C. stoebe, unlike C. jacea, accumulated fewest root-feeding nematodes in expanded range soil. Moreover, when we examined other nematode feeding groups, we found intra-specific plant population effects on all these groups. We conclude that range-expanding plant populations from the expanded range were not better defended against root-feeding nematodes than populations from the original range, but that C. stoebe might experience partial belowground enemy release.


Assuntos
Nematoides , Rizosfera , Animais , Biota , Plantas , Solo
3.
Oecologia ; 194(1-2): 205-219, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33026525

RESUMO

Successional processes can be observed for many organisms and resources, but most studies of succession have focused on plants. A general framework has been proposed, advocating that successional patterns in species turnover are predominantly driven by competition, dispersal or abiotic limitation, and that the patterning of species accumulation over time gives clues to which process is most influential in a given system. We applied this framework to succession in communities of wood-living beetles, utilizing ephemeral resources in the form of 60 experimentally created dead aspen high stumps. High stumps were created at sun-exposed sites (high ambient temperature; favourable abiotic conditions) and shaded sites (low ambient temperature; abiotically limiting conditions). The sites were intermixed, ensuring similar dispersal opportunities. Beetle species richness and abundance were monitored with flight interception traps over four consecutive years. Consistent with predictions from the tested framework, several beetle functional groups accumulated species more slowly at the unfavourable shaded sites than at the favourable exposed sites. Species richness at the exposed sites increased rapidly to a plateau, consistent with a limiting effect of competition on community development. Similar results were obtained for beetle abundance and community structure. Part of the variance in beetle community structure was jointly explained by habitat and fungal community composition, suggesting that differences in the composition and developmental rate of fungal communities in the two habitats contributed to the observed patterns. Targeted experimental studies are now required to decisively establish what processes underlie the contrasting successional trajectories in the two environments.


Assuntos
Besouros , Animais , Ecossistema , Plantas , Madeira
4.
Zootaxa ; 4779(4): zootaxa.4779.4.7, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-33055771

RESUMO

The genus Anisoderomorpha Arrow, 1925 (Coleoptera: Erotylidae: Languriinae) is redescribed and two new species of Anisoderomorpha are described: A. tamdaoensis sp. nov. from Vietnam and A. malayana sp. nov. from Malaysia. The adults of A. tamdaoensis sp. nov. were found to be sexually dimorphic in external morphology, particularly in the shape of the head and mandibles: females have a large asymmetrical head and mandibles, whereas males have a symmetrical head with slightly asymmetrical mandibles. All three members of Anisoderomorpha and its related taxon, Celolanguria curvipes Arrow, 1925, are illustrated and the host plant of Anisoderomorpha is predicted based on the morphological similarity of the specified mouthparts to those of other genera.


Assuntos
Besouros , Animais , Feminino , Cabeça , Masculino , Plantas
5.
Zootaxa ; 4855(1): zootaxa.4855.1.1, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33056354

RESUMO

Despite the species richness of hoverflies (Diptera: Syrphidae) world-wide (about 6,200 species) and their role as agents for controlling plant pests, their significance as pollinators, and as bioindicators of site quality, hoverfly fauna of Saudi Arabia is poorly known. In exploring the biodiversity of Diptera in southwest Saudi Arabia a survey of the hoverfly fauna of Jazan, Asir, Najran and Al-Baha was performed mainly using Malaise traps, sweep nets and light traps from 2011 to 2014. Forty known species of Syrphidae were identified and recorded in this study, 19 of them new to Saudi Arabia. This makes the total number of Syrphidae species recorded in Saudi Arabia (including one species recorded by others) is 41. In addition, three taxa belonging to the genera Eumerus Meigen, Orthonevra Macquart, and Paragus Latreille that could not be identified safely to species level because there were no adequate identification keys or males were missing in the collected material. A key to the genera of Syrphidae occurring in Saudi Arabia is provided. The fauna of Syrphidae recorded in this study consists much more of Afrotropical zoogeographical elements than Palaearctic ones. A complete checklist of Syrphidae of Saudi Arabia is provided. Biological data, where known, and world-wide distribution of the studied taxa are provided. This paper is published with the purpose of assisting biogeographical, biological or ecological studies on syrphids in Saudi Arabia.


Assuntos
Dípteros , Animais , Biodiversidade , Masculino , Plantas , Arábia Saudita
6.
Zootaxa ; 4838(3): zootaxa.4838.3.4, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-33056813

RESUMO

Macropsis aselae Tishechkin sp. n. from Dzhungarsky Alatau Mtn. Range, Southeastern Kazakhstan is described. The synonymy M. iliensis Mityaev, 1971 = M. tuvensis Vilbaste, 1980 syn. n. is established. Descriptions, data on distribution and host plants, and an illustrated key to 20 Macropsis species from Southeastern Kazakhstan are given.


Assuntos
Hemípteros , Distribuição Animal , Estruturas Animais , Animais , Cazaquistão , Plantas
8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1954-1957, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018385

RESUMO

Water quality has a direct impact on industry, agriculture, and public health. Algae species are common indicators of water quality. It is because algal communities are sensitive to changes in their habitats, giving valuable knowledge on variations in water quality. However, water quality analysis requires professional inspection of algal detection and classification under microscopes, which is very time-consuming and tedious. In this paper, we propose a novel multi-target deep learning framework for algal detection and classification. Extensive experiments were carried out on a large-scale colored microscopic algal dataset. Experimental results demonstrate that the proposed method leads to the promising performance on algal detection, class identification and genus identification.


Assuntos
Aprendizado Profundo , Plantas , Agricultura , Microscopia , Qualidade da Água
9.
Zootaxa ; 4802(2): zootaxa.4802.2.6, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-33056621

RESUMO

Field surveys were carried out to determine the richness of the Cynipidae fauna of Kazdagi National Park, located on the border of Edremit county (Balikesir province, Turkey). Gall samples of cynipids were collected or photographed on Quercus and Rosa host plants. As a result, 53 cynipid species belonging to 3 different tribes were found or observed in the surveyed area. 14 and 8 species were recorded as new for the Cynipidae fauna of Balikesir and Çanakkale provinces respectively, including the first locality record of Andricus hystrix Trotter, 1897 for Turkey. In addition, color photos of reared cynipid wasps from their galls and the observed cynipid galls on their host plant species are presented.


Assuntos
Quercus , Vespas , Animais , Parques Recreativos , Plantas , Turquia
10.
J Environ Qual ; 49(5): 1334-1346, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33016454

RESUMO

Limited research has focused on factors affecting pesticide losses from ornamental plant production nurseries. This project evaluated the effects of overhead irrigation or simulated rainfall intensity and formulation and application methods on the losses of acephate, bifenthrin, and imidacloprid in drainage water. The liquid formulation of each respective pesticide was applied to individual replicates (potted Ilex cornuta Lindl. & Paxton plant on a drainage collection saucer) as substrate-applied drenches or foliar sprays (acephate and bifenthrin only). Granular formulations of acephate and imidacloprid were spread across the tops of media in pots. After application of treatments, irrigation or simulated rainfall was applied daily for 19 consecutive days at rates of 42.3 ± 4.57, 56.7 ± 7.92, and 95.4 ± 19.47 ml min-1 , and drainage water from individual replicates was collected for analysis. Irrigation or simulated rainfall intensity had no effects on losses of the pesticides under the conditions tested. Concentrations in drainage of all three pesticides were highest from the drench applications, whereas respective foliar spray applications resulted in the lowest active ingredient concentrations in drainage. The percentage of active ingredient lost in drainage water ranged from a minimum of 0.2 ± 0.05% (mean ± SE) for granular acephate to a maximum of 19.5 ± 3.14% (mean ± SE) for the imidacloprid drench. Most pesticide losses occurred within the first 2 d after application of drenches or sprays. Granular formulations had a longer period of release, indicating a risk of loss from overirrigation during an extended period. Results emphasize the need for careful water management after applications.


Assuntos
Praguicidas/análise , Plantas , Água
11.
Acta amaz ; 50(3): 183-191, jul. - set. 2020.
Artigo em Inglês | LILACS | ID: biblio-1118775

RESUMO

This study aimed to evaluate and select progenies and matrices of cupuassu-tree siblings, and to select Brazilian mahogany matrices with superior characteristics to be used in agroforestry systems (AFS). Twenty-five full cupuassu tree sibling progenies and one Brazilian mahogany half-sibling progeny were evaluated. The study was conducted for 14 years in a commercial property in Tomé Açu, Pará State, Brazil. The number of fruits and fruit yield per plant, as well as the rate of plants with symptoms of witches' broom disease, were used as response variables for cupuassu. For mahogany, the following response variables were used: total height, commercial height, crown height, diameter at breast height and commercial wood volume. There were five cupuassu tree progenies with interesting characteristics to be used in AFS. Based on the high values observed in the selection accuracy and heritabilities, a good potential for the selection of promising individuals in the cupuassu tree population is inferred. Based on the ranking of genotypic values and their agronomic performance, 10 matrices of cupuassu tree were selected. For Brazilian mahogany, three matrices showed excellent silvicultural performance. The matrices of these two species should be propagated vegetatively in order to evaluate clonal tests. (AU)


Assuntos
Plantas , Melhoramento Vegetal , Genótipo
12.
Mar Environ Res ; 160: 104981, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32907719

RESUMO

Canopy-forming macroalgae recently experienced a worldwide decline. This is relevant, because canopies sustain complex food webs in temperate coasts. We assessed the die-back of the canopy-forming alga Fucus serratus in N Spain, at its warm distributional range boundary, and its effects on associated assemblages. We combined long-term descriptive surveys with canopy-removal experiments. Results showed that rapid shifts to turf-forming communities were mostly the direct consequence of the canopy loss, rather than a concurrent process directly triggered by climate change. The switch alters the whole food web, as the prominent role of F.serratus and other cold-temperate intertidal fucoids is not being replaced by functionally equivalent species. Canopy loss caused a rapid biotic homogenization at regional scale which is spreading towards the west, from the edge to the central part of the former distributional range of F.serratus in N Spain. The most obvious effect is the ecological and functional impoverishment of the coastal system.


Assuntos
Fucus , Alga Marinha , Cadeia Alimentar , Plantas , Espanha , Inquéritos e Questionários
13.
Sci Total Environ ; 741: 140452, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32886966

RESUMO

Invasive plant environments differ along latitudes and between native and introduced ranges. In response to herbivory and abiotic stresses that vary with latitudes and between ranges, invasive plants may shift their secondary chemicals to facilitate invasion success. However, it remains unclear whether and how invasive plant chemical responses to herbivory and chemical responses to abiotic environments are associated. We conducted large scale field surveys of herbivory on the invasive tallow tree (Triadica sebifera) along latitudes in both its native (China) and introduced ranges (United States) and collected leaf samples for analyses of tannins and flavonoids. We used data on climate and solar radiation to examine these chemical responses to abiotic environments and their variations along these latitudes and between ranges. We also re-analyzed previously published data from multiple common garden experiments on tallow tree to investigate genetic divergence of secondary chemical concentrations between introduced and native populations. We found foliar tannins and herbivory (chewing, sucking) were higher in the native range compared to the invasive range. Allocation to tannins versus flavonoids decreased with latitude in the native range but did not vary in the invasive range. Analyses of previously published common garden experimental data indicated genetic divergence contributes to chemical concentration differences between ranges. Our field data further indicated that the latitudinal patterns were primarily phenotypic responses to herbivory in China while in US they were primarily phenotypic responses to abiotic environments. The variation of tannins may be linked to flavonoids, given tannins and flavonoids share a biosynthesis pathway. Together, our results suggest that invasive plants adjust their secondary metabolism to decrease chemicals that primarily defend against herbivory and increase those that help them to respond to their abiotic environment. These findings deepen our understanding of how invasive plants adapt to biogeographically heterogeneous environments through trade-offs between secondary chemical responses.


Assuntos
Euphorbiaceae , Herbivoria , China , Espécies Introduzidas , Plantas
14.
Nat Commun ; 11(1): 4692, 2020 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-32943624

RESUMO

Hemicelluloses, a family of heterogeneous polysaccharides with complex molecular structures, constitute a fundamental component of lignocellulosic biomass. However, the contribution of each hemicellulose type to the mechanical properties of secondary plant cell walls remains elusive. Here we homogeneously incorporate different combinations of extracted and purified hemicelluloses (xylans and glucomannans) from softwood and hardwood species into self-assembled networks during cellulose biosynthesis in a bacterial model, without altering the morphology and the crystallinity of the cellulose bundles. These composite hydrogels can be therefore envisioned as models of secondary plant cell walls prior to lignification. The incorporated hemicelluloses exhibit both a rigid phase having close interactions with cellulose, together with a flexible phase contributing to the multiscale architecture of the bacterial cellulose hydrogels. The wood hemicelluloses exhibit distinct biomechanical contributions, with glucomannans increasing the elastic modulus in compression, and xylans contributing to a dramatic increase of the elongation at break under tension. These diverging effects cannot be explained solely from the nature of their direct interactions with cellulose, but can be related to the distinct molecular structure of wood xylans and mannans, the multiphase architecture of the hydrogels and the aggregative effects amongst hemicellulose-coated fibrils. Our study contributes to understanding the specific roles of wood xylans and glucomannans in the biomechanical integrity of secondary cell walls in tension and compression and has significance for the development of lignocellulosic materials with controlled assembly and tailored mechanical properties.


Assuntos
Parede Celular/química , Celulose/química , Extratos Vegetais/química , Plantas/química , Polissacarídeos/química , Madeira/química , Configuração de Carboidratos , Sequência de Carboidratos , Catárticos/química , Citoesqueleto/química , Hidrogéis/química , Mananas , Xilanos/química
15.
Nat Commun ; 11(1): 4720, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948753

RESUMO

Cellulose, the most abundant biopolymer on earth, is a versatile, energy rich material found in the cell walls of plants, bacteria, algae, and tunicates. It is well established that cellulose is crystalline, although the orientational order of cellulose crystallites normal to the plane of the cell wall has not been characterized. A preferred orientational alignment of cellulose crystals could be an important determinant of the mechanical properties of the cell wall and of cellulose-cellulose and cellulose-matrix interactions. Here, the crystalline structures of cellulose in primary cell walls of onion (Allium cepa), the model eudicot Arabidopsis (Arabidopsis thaliana), and moss (Physcomitrella patens) were examined through grazing incidence wide angle X-ray scattering (GIWAXS). We find that GIWAXS can decouple diffraction from cellulose and epicuticular wax crystals in cell walls. Pole figures constructed from a combination of GIWAXS and X-ray rocking scans reveal that cellulose crystals have a preferred crystallographic orientation with the (200) and (110)/([Formula: see text]) planes preferentially stacked parallel to the cell wall. This orientational ordering of cellulose crystals, termed texturing in materials science, represents a previously unreported measure of cellulose organization and contradicts the predominant hypothesis of twisting of microfibrils in plant primary cell walls.


Assuntos
Parede Celular/química , Celulose/química , Plantas/química , Arabidopsis/química , Bryopsida/química , Cristalografia , Cristalografia por Raios X , Microfibrilas/química
16.
Nat Commun ; 11(1): 4721, 2020 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-32948775

RESUMO

The importance of soil age as an ecosystem driver across biomes remains largely unresolved. By combining a cross-biome global field survey, including data for 32 soil, plant, and microbial properties in 16 soil chronosequences, with a global meta-analysis, we show that soil age is a significant ecosystem driver, but only accounts for a relatively small proportion of the cross-biome variation in multiple ecosystem properties. Parent material, climate, vegetation and topography predict, collectively, 24 times more variation in ecosystem properties than soil age alone. Soil age is an important local-scale ecosystem driver; however, environmental context, rather than soil age, determines the rates and trajectories of ecosystem development in structure and function across biomes. Our work provides insights into the natural history of terrestrial ecosystems. We propose that, regardless of soil age, changes in the environmental context, such as those associated with global climatic and land-use changes, will have important long-term impacts on the structure and function of terrestrial ecosystems across biomes.


Assuntos
Biota , Ecossistema , Solo/química , Bactérias/classificação , Biodiversidade , Biomassa , Clima , Fungos/classificação , Microbiota , Plantas/classificação , Fatores de Tempo
17.
Oecologia ; 194(1-2): 123-134, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32865688

RESUMO

Recent studies suggest that the assembly of trophic interaction networks is the result of both niche (deterministic and selective) and neutral (stochastic) processes, but we know little about their relative importance. Succession following disturbance offers a good opportunity to address this question. Studies of single-trophic guilds suggest that, shortly after a disturbance, such as a fire, neutral assembly processes (e.g. colonisation events) dominate; whereas, niche processes (selection) become more and more important as succession proceeds. Building on these observations, we predict similar changes in interaction networks during succession, with a shift from stochastic toward selective interactions. To test this, we studied succession of plant-herbivorous insect networks in South Africa after a fire. We sampled a total of 385 herbivorous arthropod species and 92 plant species. For different successional stages and spatial grain sizes, we used network descriptors to estimate plant-herbivore specificity and partner fidelity of plant and herbivore species across networks (i.e. localities). We compared the observed network descriptors to neutral models, and then differentiated selective species (associated with similar partner species in different networks) from neutral species (associated at random with their partners). Our results suggest that specialisation, partner fidelity and the proportion of selective species of plants and herbivores increased with succession, which is consistent with the hypothesis that niche-based processes prevail over neutral processes as succession proceeds. However, in all the successional stages, the majority of species were neutral species, which pinpoints the importance of opportunistic interactions in the assembly of trophic networks.


Assuntos
Fogo , Herbivoria , Animais , Ecossistema , Plantas , África do Sul , Processos Estocásticos
18.
Nature ; 585(7826): 507-508, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32895562
19.
Nat Commun ; 11(1): 4621, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32963240

RESUMO

Arctic warming can influence tundra ecosystem function with consequences for climate feedbacks, wildlife and human communities. Yet ecological change across the Arctic tundra biome remains poorly quantified due to field measurement limitations and reliance on coarse-resolution satellite data. Here, we assess decadal changes in Arctic tundra greenness using time series from the 30 m resolution Landsat satellites. From 1985 to 2016 tundra greenness increased (greening) at ~37.3% of sampling sites and decreased (browning) at ~4.7% of sampling sites. Greening occurred most often at warm sampling sites with increased summer air temperature, soil temperature, and soil moisture, while browning occurred most often at cold sampling sites that cooled and dried. Tundra greenness was positively correlated with graminoid, shrub, and ecosystem productivity measured at field sites. Our results support the hypothesis that summer warming stimulated plant productivity across much, but not all, of the Arctic tundra biome during recent decades.


Assuntos
Ecossistema , Estações do Ano , Tundra , Regiões Árticas , Mudança Climática , Monitoramento Ambiental , Desenvolvimento Vegetal , Plantas , Solo , Temperatura
20.
PLoS One ; 15(8): e0238396, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32866180

RESUMO

The effect of different management techniques for plant control in the vineyard were compared in the present work, focusing on plant diversity preservation and management efficacy in a two-year experiment on vineyard row weed community. Biomass-fueled flame weeding (with two intensities) was applied as an innovative plant control technique in contrast to tillage and mowing practices. The results showed that flaming was comparable to tillage regarding weed control effectiveness, and was more efficient than mowing. However, species number and functional evenness were not substantially modified by changing the applied management technique. Functional trait analysis demonstrated that row management significantly affected the frequency of annual plants, plant height, root depth index, and the occurrence of plants with storage organs. As for species composition, meaningful differences were found: only the two flaming treatments (i.e. gentle vs intense) and the gentle flaming vs mowing had consistent species composition. Flame wedding showed some potential benefits in plant control in the vineyard by favouring small plant and controlling overall weed abundance. On the other hand, flaming favoured plant species with asexual reproduction, with a potential negative impact on weed-vine competition and species persistence in the vineyard. Further studies are required to investigate such contrasting aspects, also considering other weed control techniques (e.g. cover-crops), considering a sustainable perspective of an herbicide-free environment.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Plantas Daninhas/efeitos dos fármacos , Poaceae/crescimento & desenvolvimento , Controle de Plantas Daninhas/métodos , Agricultura/métodos , Biodiversidade , Biomassa , Produtos Agrícolas/efeitos dos fármacos , Fazendas , Herbicidas/farmacologia , Plantas/efeitos dos fármacos , Poaceae/efeitos dos fármacos
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