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1.
Nat Commun ; 12(1): 3381, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099669

RESUMO

Nutrient amendment diminished bacterial functional diversity, consolidating carbon flow through fewer bacterial taxa. Here, we show strong differences in the bacterial taxa responsible for respiration from four ecosystems, indicating the potential for taxon-specific control over soil carbon cycling. Trends in functional diversity, defined as the richness of bacteria contributing to carbon flux and their equitability of carbon use, paralleled trends in taxonomic diversity although functional diversity was lower overall. Among genera common to all ecosystems, Bradyrhizobium, the Acidobacteria genus RB41, and Streptomyces together composed 45-57% of carbon flow through bacterial productivity and respiration. Bacteria that utilized the most carbon amendment (glucose) were also those that utilized the most native soil carbon, suggesting that the behavior of key soil taxa may influence carbon balance. Mapping carbon flow through different microbial taxa as demonstrated here is crucial in developing taxon-sensitive soil carbon models that may reduce the uncertainty in climate change projections.


Assuntos
Ciclo do Carbono , Mudança Climática , Nutrientes/metabolismo , Microbiologia do Solo , Solo/química , Acidobacteria/genética , Acidobacteria/isolamento & purificação , Acidobacteria/metabolismo , Biodiversidade , Bradyrhizobium/genética , Bradyrhizobium/isolamento & purificação , Bradyrhizobium/metabolismo , Carbono/metabolismo , DNA Bacteriano/isolamento & purificação , Monitorização de Parâmetros Ecológicos/métodos , Previsões/métodos , Fósforo/metabolismo , RNA Ribossômico 16S/genética , Streptomyces/genética , Streptomyces/isolamento & purificação , Streptomyces/metabolismo
2.
Sci Rep ; 11(1): 8231, 2021 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-33859208

RESUMO

This proposal investigates the effect of vegetation height and density on received signal strength between two sensor nodes communicating under IEEE 802.15.4 wireless standard. With the aim of investigating the path loss coefficient of 2.4 GHz radio signal in an IEEE 802.15.4 precision agriculture monitoring infrastructure, measurement campaigns were carried out in different growing stages of potato and wheat crops. Experimental observations indicate that initial node deployment in the wheat crop experiences network dis-connectivity due to increased signal attenuation, which is due to the growth of wheat vegetation height and density in the grain-filling and physical-maturity periods. An empirical measurement-based path loss model is formulated to identify the received signal strength in different crop growth stages. Further, a NSGA-II multi-objective evolutionary computation is performed to generate initial node deployment and is optimized over increased coverage, reduced over-coverage, and received signal strength. The results show the development of a reliable wireless sensor network infrastructure for wheat crop monitoring.


Assuntos
Agricultura , Algoritmos , Monitorização de Parâmetros Ecológicos/métodos , Solanum tuberosum/genética , Triticum/genética , Agricultura/instrumentação , Agricultura/métodos , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Redes de Comunicação de Computadores , Produtos Agrícolas/genética , Monitorização de Parâmetros Ecológicos/instrumentação , Meio Ambiente , Testes Genéticos/instrumentação , Testes Genéticos/métodos , Reprodutibilidade dos Testes , Solanum tuberosum/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento , Tecnologia sem Fio
3.
Urology ; 142: 106-111, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32289364

RESUMO

OBJECTIVE: To investigate the symptom deterioration of patients with benign prostatic hyperplasia (BPH) according to the difference in daily temperature. PATIENTS AND METHODS: From the National Health Insurance Service database, we collected and analyzed data on patients with BPH in 6 major metropolitan areas in Korea between January 2008 and December 2017. We investigated the rate of emergency room visits as well as the rate of urethral catheter insertion. RESULTS: In total, 1,446,465 patients were enrolled in this study. When the daily temperature difference was below 4°C, 28.5 patients visited the emergency room daily, while 42.2 patients visited the emergency room daily when the daily temperature difference exceeded 14°C. When the daily temperature difference was more than 14°C, about 48.0% more patients visited the emergency room than when the daily temperature difference was below 4°C. After visiting the emergency room, there were 11.9 patients who had a catheter inserted daily at the daily temperature difference below 4°C. When the daily temperature difference was more than 14°C, the number of catheter insertion cases was 17.8 patients daily, which was 49.2% higher than that of below 4°C. By time, surgery was performed most frequently within 3 months after visiting the emergency room. CONCLUSION: Day temperature difference appear to be related to the Lower urinary tract symptom of BPH patients.


Assuntos
Temperatura Baixa/efeitos adversos , Sintomas do Trato Urinário Inferior/diagnóstico , Hiperplasia Prostática/diagnóstico , Cateterismo Urinário/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Monitorização de Parâmetros Ecológicos/estatística & dados numéricos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Humanos , Sintomas do Trato Urinário Inferior/etiologia , Sintomas do Trato Urinário Inferior/terapia , Masculino , Pessoa de Meia-Idade , Programas Nacionais de Saúde/estatística & dados numéricos , Hiperplasia Prostática/complicações , Hiperplasia Prostática/terapia , República da Coreia , Exacerbação dos Sintomas
4.
Mar Environ Res ; 149: 126-136, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31221492

RESUMO

Anthropogenic subsidies to natural systems can influence the diet of mobile omnivore species and co-occurring species. This study assessed if fall-off from mussel aquaculture subsidized wild populations of mobile scavengers and predators, such as the commercially important lobster Homarus americanus. A Bayesian stable isotope-mixing model with parameters determined from the literature and from a 105 days laboratory feeding experiment was applied to wild lobsters to determine how important the various food sources were in these lobsters, especially mussel fall-off. Isotopic values were mainly affected by lobster size with model outputs indicating that large lobsters (>80 mm cephalothorax) fed mainly on mussels from the mussel farm (46% of the diet) while small ones fed mostly on the rock crab Cancer irroratus (99%). The contribution of mussel subsidies to the lobster's diet was thus size-specific and direct (i.e. through mussel fall-off and not through co-occurring species such as rock crab). The absence of a link between food sources and lipid energy content in lobsters suggested that the reduction of rock crab consumption would have to be more drastic to affect the general health of large lobsters in the short term.


Assuntos
Aquicultura , Bivalves , Dieta , Cadeia Alimentar , Nephropidae/fisiologia , Animais , Braquiúros , Monitorização de Parâmetros Ecológicos , Glicogênio/análise , Marcação por Isótopo , Lipídeos/análise , Modelos Teóricos , Valor Nutritivo , Proteínas/análise , Alimentos Marinhos
5.
Mar Environ Res ; 148: 81-86, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31108339

RESUMO

Regular discharges of produced water from the oil and gas industry represents the largest direct discharge of effluent into the marine environment worldwide. Organic compound classes typically reported in produced water include saturated hydrocarbons, monoaromatic and polyaromatic hydrocarbons (MAHs, PAHs) as well as oxygenated compounds, such as phenols, acids and ketones. This forms a cocktail of known and suspect toxicants, but limited knowledge is yet available on the sub-lethal toxicity of produced water to cold-water marine fish species. In the present work, we conducted a 4-day exposure of embryos of Atlantic cod (Gadus morhua) and haddock (Melanogrammus aeglefinus) to produced water extracts equivalent to 1:50, 1:500 and 1:5000 times dilutions of raw effluent. No significant reduction in survival or hatching success was observed, however, for cod, hatching was initiated earlier for exposed embryos in a concentration-dependent manner. During recovery, significantly reduced embryonic heart rate was observed for both species. After hatch, larvae subjected to embryonic exposure to produced water extracts were smaller, and displayed signs of cardiotoxicity, jaw and craniofacial deformations. In order to improve risk assessment and regulation of produced water discharges, it is important to identify which produced water components contribute to these effects.


Assuntos
Cardiotoxicidade , Embrião não Mamífero , Gadiformes , Gadus morhua , Poluentes Químicos da Água/toxicidade , Animais , Regiões Árticas , Monitorização de Parâmetros Ecológicos , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/patologia , Gadiformes/embriologia , Gadus morhua/embriologia , Hidrocarbonetos/toxicidade , Petróleo/toxicidade , Poluição por Petróleo , Fenóis/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade
6.
Mar Environ Res ; 146: 80-88, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30926196

RESUMO

Long-term environmental records are among the most valuable assets for understanding the trajectory and consequences of climate change. Here we report on a newly recovered time-series from Project Oceanology, a non-profit ocean science organization serving New England schools (USA) since 1972. As part of its educational mission, Project Oceanology has routinely and consistently recorded water temperature, pH, and oxygen as well as invertebrate and fish abundance in nearshore waters of the Thames River estuary in eastern Long Island Sound (LIS). We digitized these long-term records to test for decadal trends in abiotic and biotic variables including shifts in species abundance, richness, and diversity. Consistent with previous studies, the data revealed an above-average warming rate of eastern LIS waters over the past four decades (+0.45 °C decade-1), a non-linear acidification trend twice the global average (-0.04 pH units decade-1), and a notable decline in whole water-column dissolved oxygen concentrations (-0.29 mg L-1 decade-1). Trawl catches between 1997 and 2016 suggested a significant decrease in overall species diversity and richness, declines in cold-water adapted species such as American lobster (Homarus americanus), rock crab (Cancer irroratus), and winter flounder (Pseudopleuronectes americanus), but concurrent increases in the warm-water decapod Libinia emarginata (spider crab). Our study confirmed that Long Island Sound is a rapidly changing urban estuary, while demonstrating the value of long-term observations made by citizen-scientists, educators, and other stakeholders.


Assuntos
Mudança Climática/estatística & dados numéricos , Monitorização de Parâmetros Ecológicos , Estuários , Animais , Biodiversidade , Braquiúros , Ciência do Cidadão , Peixes , Linguado , Nephropidae , New England , Temperatura
7.
Sci Total Environ ; 657: 717-730, 2019 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-30677937

RESUMO

Nutrient dynamics in a 25 km long treated wastewater effluent impacted reach of a large, gravel-bed river were evaluated in five river compartments: surficial sediment, surface water, hyporheic zone water, and aquatic biomass (including epilithic algae and macrophytes). Nutrient storage within, and export from, the river reach, was quantified to assess the impact of WWTP effluent on nutrient dynamics. More than 98% of N and P storage was found in the surficial river bed sediment, where it is available to support epilithic algal and macrophyte growth. Nutrient export from the river reach by sediment, hyporheic water, and biomass were small compared to water column transport. The N:P ratios for the five different compartments suggested that the water column was severely P limited, whereas sediment, hyporheic water, and aquatic biomass tended towards co-limitation and N limitation. Within the river reach, the majority of P was stored immediately downstream of the WWTP effluent outfall, whereas N was retained at a higher rate relative to P in the remainder of the reach. Correlation analysis of nutrient exchange between different compartments suggested that multiple nutrient compartments should be considered when establishing nutrient loading criteria. Nutrient analysis in multiple compartments in the river can add valuable insight into nutrient dynamics and nutrient limitation.


Assuntos
Sedimentos Geológicos/análise , Nitrogênio/análise , Fósforo/análise , Rios , Alberta , Cidades , Monitorização de Parâmetros Ecológicos , Plantas , Análise Espaço-Temporal , Eliminação de Resíduos Líquidos
8.
PLoS One ; 13(8): e0201137, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30133444

RESUMO

Activities of ecosystem engineers can interact with other disturbances to modulate rates of key processes such as productivity and nutrient cycling. Bioturbation, movement of soil by organisms, is a widespread form of ecosystem engineering in terrestrial ecosystems. We propose that bioturbation by southeastern pocket gophers (Geomys pinetis), an abundant but declining ecosystem engineer in longleaf pine (Pinus palustris Mill.) forests, accelerates nutrient dynamics of the forest floor by burying litter and then reduces litter consumption and nitrogen (N) volatilization losses in the presence of fire. We evaluated our hypothesis by measuring how litter burial alters decomposition and N and phosphorus (P) turnover of longleaf pine and turkey oak (Quercus laevis Walt.) litter over four years, and then simulated interactive ecosystem-level effects of litter burial and low-intensity fires on N and P dynamics of the litter layer. In the field, mass loss was over two times greater and N and P were released much more rapidly from litter buried beneath mounds than on the surface of the forest floor. At a measured rate of mound formation covering 2.3 ± 0.6% of the forest floor per year, litter mass and N and P content of the forest floor simulated over an eight-year period were approximately 11% less than amounts in areas without pocket gopher mounds. In contrast to unburied litter, litter beneath mounds is protected from consumption during fires, and as fire interval increased, consumption rates decreased because mounds cover more years of accumulated litter. Our research indicates that bioturbation and burial of litter by pocket gophers accelerates turnover of N and P on the forest floor, and in the presence of fire, conserves N in this ecosystem where productivity is known to be nutrient limited.


Assuntos
Monitorização de Parâmetros Ecológicos/métodos , Ecossistema , Solo/química , Animais , Incêndios , Florestas , Geômis , Mamíferos , Nitrogênio/química , Nutrientes , Valor Nutritivo , Fósforo/química , Pinus , Folhas de Planta/química , Árvores
9.
Sci Rep ; 8(1): 10029, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29968739

RESUMO

Cellulose and lignin are the main polymeric components of the forest litter horizon. We monitored microbial community composition using phospholipid fatty acid (PLFA) analysis and investigated the ligninolytic and cellulolytic enzyme activities of the litter horizon across an alpine treeline ecotone in the eastern Tibetan Plateau. The activities of ligninolytic and cellulolytic enzymes and the biomass of microbial PLFAs were higher in the initial stage of litter decomposition than in the latter stage in the three vegetation types (coniferous forest, alpine shrubland and alpine meadow). Soil microbial community structure varied significantly over the course of litter decomposition in the three vegetation types. Furthermore, the BIOENV procedure revealed that the carbon to nitrogen (C:N) ratio, carbon to phosphorus (C:P) ratio and moisture content (MC) were the most important determinants of microbial community structure in the initial stage of litter decomposition, whereas pH and the lignin concentration were the major factors influencing the microbial community structure in the later stage of litter decomposition. These findings indicate that litter quality drives the differentiation of microbial communities in the litter horizon across an alpine treeline ecotone in the eastern Tibetan Plateau.


Assuntos
Celulose/análise , Lignina/análise , Resíduos/efeitos adversos , Altitude , Biomassa , Carbono/análise , Monitorização de Parâmetros Ecológicos/métodos , Ecossistema , Ácidos Graxos/análise , Florestas , Concentração de Íons de Hidrogênio , Microbiota , Nitrogênio/análise , Fosfolipídeos/análise , Fósforo/análise , Folhas de Planta/química , Estações do Ano , Solo/química , Microbiologia do Solo , Temperatura , Tibet , Traqueófitas
10.
Mar Pollut Bull ; 125(1-2): 103-114, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28802659

RESUMO

Large areas of hypoxia have been reported off The Changjiang Estuary and in the East China Sea. Five cruises, covering winter, spring, and summer, were carried out from 2007 to 2013 in this region, and in August 2013 (summer), an extensive hypoxic event (11,150km2) was observed, which was characterized by an estimated bulk oxygen depletion of 5.1 million tons. A strong tidal impact was observed associated with the bottom oxygen depletion, with the periodicity of diel variations in dissolved oxygen being 12h (i.e., similar to the tidal cycle). A conservative estimate of nutrient regeneration suggested that during the hypoxic event of August 2013, the amount of regenerated nitrogen (as nitrate) and phosphorus (as dissolved inorganic phosphorus) was 27,000-30,000 tons and 1300-41,000tons, respectively. Estimates of the absolute (bulk) regenerated nutrient fluxes were much greater than the conservative estimates.


Assuntos
Monitorização de Parâmetros Ecológicos/métodos , Estuários , Oxigênio/análise , China , Monitoramento Ambiental , Nitratos/análise , Nitrogênio/análise , Fósforo/análise , Rios , Estações do Ano
11.
Water Res ; 125: 141-151, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28843938

RESUMO

Traditionally, the monitoring of streams for chemical and ecological status has been limited to surface water concentrations, where the dominant focus has been on general water quality and the risk for eutrophication. Mixed land use stream systems, comprising urban areas and agricultural production, are challenging to assess with multiple chemical stressors impacting stream corridors. New approaches are urgently needed for identifying relevant sources, pathways and potential impacts for implementation of suitable source management and remedial measures. We developed a method for risk assessing chemical stressors in these systems and applied the approach to a 16-km groundwater-fed stream corridor (Grindsted, Denmark). Three methods were combined: (i) in-stream contaminant mass discharge for source quantification, (ii) Toxic Units and (iii) environmental standards. An evaluation of the chemical quality of all three stream compartments - stream water, hyporheic zone, streambed sediment - made it possible to link chemical stressors to their respective sources and obtain new knowledge about source composition and origin. Moreover, toxic unit estimation and comparison to environmental standards revealed the stream water quality was substantially impaired by both geogenic and diffuse anthropogenic sources of metals along the entire corridor, while the streambed was less impacted. Quantification of the contaminant mass discharge originating from a former pharmaceutical factory revealed that several 100 kgs of chlorinated ethenes and pharmaceutical compounds discharge into the stream every year. The strongly reduced redox conditions in the plume result in high concentrations of dissolved iron and additionally release arsenic, generating the complex contaminant mixture found in the narrow discharge zone. The fingerprint of the plume was observed in the stream several km downgradient, while nutrients, inorganics and pesticides played a minor role for the stream health. The results emphasize that future investigations should include multiple compounds and stream compartments, and highlight the need for holistic approaches when risk assessing these dynamic systems.


Assuntos
Monitorização de Parâmetros Ecológicos/métodos , Poluentes Químicos da Água/análise , Dinamarca , Monitoramento Ambiental/métodos , Eutrofização , Água Subterrânea/química , Metais/análise , Praguicidas/análise , Rios/química , Poluentes Químicos da Água/química , Qualidade da Água
12.
PLoS One ; 11(5): e0155411, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27182604

RESUMO

In Italy a nation-wide monitoring network was established in 2009 in response to significant honey bee colony mortality reported during 2008. The network comprised of approximately 100 apiaries located across Italy. Colonies were sampled four times per year, in order to assess the health status and to collect samples for pathogen, chemical and pollen analyses. The prevalence of Nosema ceranae ranged, on average, from 47-69% in 2009 and from 30-60% in 2010, with strong seasonal variation. Virus prevalence was higher in 2010 than in 2009. The most widespread viruses were BQCV, DWV and SBV. The most frequent pesticides in all hive contents were organophosphates and pyrethroids such as coumaphos and tau-fluvalinate. Beeswax was the most frequently contaminated hive product, with 40% of samples positive and 13% having multiple residues, while 27% of bee-bread and 12% of honey bee samples were contaminated. Colony losses in 2009/10 were on average 19%, with no major differences between regions of Italy. In 2009, the presence of DWV in autumn was positively correlated with colony losses. Similarly, hive mortality was higher in BQCV infected colonies in the first and second visits of the year. In 2010, colony losses were significantly related to the presence of pesticides in honey bees during the second sampling period. Honey bee exposure to poisons in spring could have a negative impact at the colony level, contributing to increase colony mortality during the beekeeping season. In both 2009 and 2010, colony mortality rates were positively related to the percentage of agricultural land surrounding apiaries, supporting the importance of land use for honey bee health.


Assuntos
Abelhas , Nível de Saúde , Animais , Criação de Abelhas , Abelhas/química , Abelhas/fisiologia , Monitorização de Parâmetros Ecológicos , Monitoramento Ambiental , Geografia , Interações Hospedeiro-Patógeno , Itália , Praguicidas/análise , Pólen , Vigilância da População
13.
Gig Sanit ; 95(6): 521-4, 2016.
Artigo em Russo | MEDLINE | ID: mdl-29424217

RESUMO

The paper presents information about the content of benzo(a)pyrene in soil samples of petroleum products and the content of heavy metals (iron, copper, lead, arsenic, manganese, chromium, cadmium and mercury) in the soil and hair samples of children. Soil samples and hair were taken in October 2014 in the north-western part of the Yamal-Nenets Autonomous District. The values obtained were compared with the approximately permissible levels and maximum allowable concentrations adopted in the Russian Federation. Levels are determined compounds in the soil in general do not exceed the allowable concentrations. In hair samples there was noted marked exceeding of the recommended values for zinc, copper, chromium and iron 10%, 16.7%, 83.3% and 100% samples, respectively. The cause of the high iron content in the hair samples may be due to the quality of consumed water, which is characterized by low mineralization and high iron content. Increased chromium content of more than 80% of the hair samples can be caused, as in the case of iron, the quality of water consumed, but also a high proportion of local foods in the diet of people, rich by chromium. A conducted study on the state of the environment in the village, away from areas of hydrocarbon production, indicates to the low importance of anthropogenic impact.


Assuntos
Cabelo/química , Metais Pesados , Poluentes do Solo , Poluentes Químicos da Água , Regiões Árticas/epidemiologia , Benzo(a)pireno/análise , Criança , Monitorização de Parâmetros Ecológicos/métodos , Monitorização de Parâmetros Ecológicos/normas , Monitoramento Ambiental/métodos , Monitoramento Ambiental/normas , Feminino , Humanos , Masculino , Metais Pesados/análise , Metais Pesados/classificação , Petróleo/análise , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Federação Russa/epidemiologia , Poluentes do Solo/análise , Poluentes do Solo/normas , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/normas
14.
Genome ; 58(5): 151-62, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26444714

RESUMO

The 6th International Barcode of Life Conference (Guelph, Canada, 18-21 August 2015), themed Barcodes to Biomes, showcases the latest developments in DNA barcoding research and its diverse applications. The meeting also provides a venue for a global research community to share ideas and to initiate collaborations. All plenary and contributed abstracts are being published as an open-access special issue of Genome. Here, I use a comparison with the 3rd Conference (Mexico City, 2009) to highlight 10 recent and emerging trends that are apparent among the contributed abstracts. One of the outstanding trends is the rising proportion of abstracts that focus upon multiple socio-economically important applications of DNA barcoding, including studies of agricultural pests, quarantine and invasive species, wildlife forensics, disease vectors, biomonitoring of ecosystem health, and marketplace surveys evaluating the authenticity of seafood products and medicinal plants. Other key movements include the use of barcoding and metabarcoding approaches for dietary analyses-and for studies of food webs spanning three or more trophic levels-as well as the spread of next-generation sequencing methods in multiple contexts. In combination with the rising taxonomic and geographic scope of many barcoding iniatives, these developments suggest that several important questions in biology are becoming tractable. "What is this specimen on an agricultural shipment?", "Who eats whom in this whole food web?", and even "How many species are there?" are questions that may be answered in time periods ranging from a few years to one or a few decades. The next phases of DNA barcoding may expand yet further into prediction of community shifts with climate change and improved management of biological resources.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Animais , Biodiversidade , Monitorização de Parâmetros Ecológicos , Humanos
15.
Sci Total Environ ; 468-469: 1178-86, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23579204

RESUMO

Managing phosphorus in catchments is central to improving surface water quality, but knowing how much can be mitigated from agricultural land, and at what cost relative to a natural baseline (or reference condition), is difficult to assess. The difference between median concentrations now and under reference was defined as the anthropogenic loss, while the manageable loss was defined as the median P concentration possible without costing more than 10% of farm profitability (measured as earnings before interest and tax, EBIT). Nineteen strategies to mitigate P loss were ranked according to cost (low, medium, high, very high). Using the average dairy and drystock farms in 14 grassland catchments as test cases, the potential to mitigate P loss from land to water was then modelled for different strategies, beginning with strategies within the lowest cost category from best to least effective, before applying a strategy from a more expensive category. The anthropogenic contribution to stream median FRP and TP concentrations was estimated as 44 and 69%, respectively. However, applying up to three strategies per farm theoretically enabled mitigation of FRP and TP losses sufficient to maintain aesthetic and trout fishery values to be met and at a cost <1% EBIT for drystock farms and <6% EBIT for dairy farms. This shows that defining and acting upon the manageable loss in grassland catchments (with few point sources) has potential to achieve a water quality outcome within an ecological target at little cost.


Assuntos
Agricultura/métodos , Monitorização de Parâmetros Ecológicos/métodos , Fósforo/análise , Rios/química , Poluentes Químicos da Água/análise , Poluição da Água/prevenção & controle , Qualidade da Água/normas , Agroquímicos/análise , Nova Zelândia , Fósforo/metabolismo , Poaceae/metabolismo , Solo/química
16.
J Environ Sci (China) ; 25(7): 1379-85, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24218850

RESUMO

The indicator values of microfauna functional groups and species for treatment performance were systematically evaluated based on the continuous monitoring of the entire microfauna communities including both protozoa and metazoa over a period of 14 months, in two parallel full-scale municipal wastewater treatment systems in a plant in Beijing, China. A total of 57 species of ciliates, 14 species (units) of amoebae, 14 species (units) of flagellates and 4 classes of small metazoa were identified, with Arcella hemisphaerica, Vorticella striata, Vorticella convallaria, Epistylis plicatilis and small flagellates (e.g. Bodo spp.) as the dominant protozoa, and rotifers as the dominant metazoa. The abundance of the sessile ciliates was correlated with the removals of BOD5 (Pearson's r = 0.410, p < 0.05) and CODcr (r = 0.397, p < 0.05) while the testate amoebae was significantly positively related to nitrification (r = 0.523, p < 0.01). At the same time, some other associations were also identified: the abundances of the large flagellates (r = 0.447, p < 0.01), the metazoa (r = 0.718, p < 0.01) and species Aspidisca sulcata (r = 0.337, p < 0.05) were positively related to nitrification; the abundance of Aspidisca costata was correlated to the TN (total nitrogen) removal (r = -0.374, p < 0.05 ); the abundances of the sessile species Carchesium polypinum (r = 0.458, p < 0.01) and E. plicatilis (r = 0.377, p < 0.05) were correlated with the removal of suspended solids.


Assuntos
Biodiversidade , Eliminação de Resíduos Líquidos , Amoeba , Animais , Análise da Demanda Biológica de Oxigênio , Cilióforos , Monitorização de Parâmetros Ecológicos , Euglênidos , Nitratos/análise , Nitrogênio/análise , Fósforo/análise , Densidade Demográfica , Rotíferos , Poluentes da Água/análise
17.
Philos Trans R Soc Lond B Biol Sci ; 368(1625): 20120406, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23878342

RESUMO

We review the literature and find 16 studies from across Africa's savannas and woodlands where woody encroachment dominates. These small-scale studies are supplemented by an analysis of long-term continent-wide satellite data, specifically the Normalized Difference Vegetation Index (NDVI) time series from the Global Inventory Modeling and Mapping Studies (GIMMS) dataset. Using dry-season data to separate the tree and grass signals, we find 4.0% of non-rainforest woody vegetation in sub-Saharan Africa (excluding West Africa) significantly increased in NDVI from 1982 to 2006, whereas 3.52% decreased. The increases in NDVI were found predominantly to the north of the Congo Basin, with decreases concentrated in the Miombo woodland belt. We hypothesize that areas of increasing dry-season NDVI are undergoing woody encroachment, but the coarse resolution of the study and uncertain relationship between NDVI and woody cover mean that the results should be interpreted with caution; certainly, these results do not contradict studies finding widespread deforestation throughout the continent. However, woody encroachment could be widespread, and warrants further investigation as it has important consequences for the global carbon cycle and land-climate interactions.


Assuntos
Conservação dos Recursos Naturais/história , Árvores , Clima Tropical , África Subsaariana , Ciclo do Carbono , Mudança Climática , Conservação dos Recursos Naturais/estatística & dados numéricos , Conservação dos Recursos Naturais/tendências , Monitorização de Parâmetros Ecológicos , Ecossistema , História do Século XX , História do Século XXI , Chuva , Árvores/metabolismo
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