Can environmental constraints determine random patterns of plant species co-occurrence?

Plant community ecologists use the null model approach to infer assembly processes from observed patterns of species co-occurrence. In about a third of published studies, the null hypothesis of random assembly cannot be rejected. When this occurs, plant ecologists interpret that the observed random pattern is not environmentally constrained - but probably generated by stochastic processes. The null model approach (using the C-score and the discrepancy index) was used to test for random assembly under two simulation algorithms. Logistic regression, distance-based redundancy analysis, and constrained ordination were used to test for environmental determinism (species segregation along environmental gradients or turnover and species aggregation). This article introduces an environmentally determined community of alpine hydrophytes that presents itself as randomly assembled. The pathway through which the random pattern arises in this community is suggested to be as follows: Two simultaneous environmental processes, one leading to species aggregation and the other leading to species segregation, concurrently generate the observed pattern, which results to be neither aggregated nor segregated - but random. A simulation study supports this suggestion. Although apparently simple, the null model approach seems to assume that a single ecological factor prevails or that if several factors decisively influence the community, then they all exert their influence in the same direction, generating either aggregation or segregation. As these assumptions are unlikely to hold in most cases and assembly processes cannot be inferred from random patterns, we would like to propose plant ecologists to investigate specifically the ecological processes responsible for observed random patterns, instead of trying to infer processes from patterns

Poder local, cidadania e participa����o popular no munic��pio de Maric��: uma an��lise cr��tica das regras do jogo

O tema que nos propomos a estudar �� o Poder local, cidadania e participa����o popular no munic��pio de Maric��. A delimita����o espa��o temporal de nosso projeto situa-se na cidade de Maric��, localizada na Sub-regi��o dos Lagos, no Estado do Rio de Janeiro, a partir do ano de 2009, tendo como pano de fundo as especificidades da forma����o social brasileira e as determina����es estruturais resultantes da mundializa����o do capital. �� importante ressaltar que o termo participa����o popular pertinente a este estudo refere-se �� cria����o ou amplia����o de canais institucionais para interven����o da popula����o no controle social ou na constru����o do debate or��ament��rio nas cidades, que exigem estrat��gias pol��ticas que s��o absolutamente fundamentais para a constru����o de uma nova sociedade pautada em princ��pios radicalmente democr��ticos.As contradi����es e as possibilidades da luta pelo direito �� cidade, frente �� amplia����o mercantiliza����o do espa��o e a tradi����o clientelista na cidade de Maric��, foram os desafios que procuraremos responder nesta tese. Para tal, elencamos as seguintes hip��teses: 1) a disputa de projetos societ��rios, a partir da luta de classes, pode ser identificada nas cidades atrav��s das propostas antag��nicas de cidade-mercadoria e do direito �� cidade, contradi����es estas que se reproduzem inclusive em governos municipais comprometidos com a amplia����o dos canais de participa����o popular; 2) a gest��o participativa municipal pode tanto contribuir para a subjetiva����o das classes subalternas no sentido das mesmas intervirem e at�� modificarem a esfera p��blica, quanto se tornar um espa��o instrumental ao clientelismo e/ou associativismo local; 3) para evitar tal distor����o �� importante que agentes contestat��rios da sociedade civil retomem o tensionamento de canais institucionais de participa����o popular nas cidades, enquanto estrat��gia de amplia����o da esfera p��blica, visto que tais espa��os t��m sido ocupados por agentes muito mais colaborativos que conflituosos, despolitizando possibilidades, tais como: o or��amento participativo, audi��ncias p��blicas e os Conselhos Municipais; 4) as cidades do CONLESTE, em especial o munic��pio de Maric��, tornaram-se foco do interesse da burguesia nacional e internacional, ap��s as discuss��es em torno do COMPERJ e do Pr��-sal, dificultando e/ou inviabilizado um direcionamento aut��nomo do poder local em torno das propostas engendradas pela participa����o popular na cidade, contexto que torna o urgente o tensionamento visando �� possibilidade de garantia da fun����o social da cidade, conforme preconiza a Carta Mundial de Direito �� Cidade, em especial frente �� especula����o imobili��ria.

On China's lake fisheries development

An account is given of the current situation regarding the lake fisheries and fish culture practices in China. The modern lake fisheries take advantage of the 3-D spaces of lakes to fully develop the resources. Currently, the fisheries concentrate on the following 3 aspects: bringing the water body into full play; various types of aquaculture enclosures; and selective measures in resources protection, stocking and aquaculture.

Aplica����o da t��cnica simulated annealing na investiga����o da ciclagem de nitrog��nio na inteface ��gua-sedimento

Neste trabalho �� apresentado a aplica����o de um m��todo de otimiza����o a fim de estimar par��metros que normalmente est��o presentes na modelagem matem��tica da din��mica de esp��cies qu��micas na interface ��gua-sedimento. O Problema Direto aqui consistiu na simula����o das concentra����es das esp��cies org��nicas e inorg��nicas (am��nia e nitrato) de nitrog��nio, num ambiente idealizado, o qual foi fracionado em quatro camadas: uma camada de ��gua (1 metro) e tr��s camadas de sedimento (0-1 cm, 1-2 cm e 2-10 cm). O Problema Direto foi resolvido pelo M��todo de Runge Kutta, tendo sido gerada uma simula����o de 50 dias. Na estimativa dos coeficientes de difus��o e porosidade foi aplicado o M��todo Simulated Annealing (SA). A efici��ncia da estrat��gia aqui adotada foi avaliada atrav��s do confronto entre dados experimentais sint��ticos e as concentra����es cal��adas pela solu����o do Problema Direto, adotando-se os par��metros estimados pela SA. O melhor ajuste entre dados experimentais e valores calculados se deu quando o par��metro estimado foi a porosidade. Com rela����o �� minimiza����o da fun����o objetivo, a estimativa desse par��metro tamb��m foi a que exigiu menor esfor��o computacional. Ap��s a introdu����o de um ru��do rand��mico ��s concentra����es das esp��cies nitrogenadas, a t��cnica SA n��o foi capaz de obter uma estimativa satisfat��ria para o coeficiente de difus��o, com exce����o da camada 0-1 cm sedimentar. Para outras camadas, erros da ordem de 10 % foram encontrados (para am��nia na coluna d��gua, pro exemplo). Os resultados mostraram que a metodologia aqui adotada pode ser bastante promissora enquanto ferramenta de gest��o de corpos d��gua, especialmente daqueles submetidos a um regime de baixa energia, como lagos e lagoas costeiras.

Avalia����es t��cnico-operacionais em esta����es de tratamento de ��gua dos munic��pios das regi��es leste e dos lagos do Estado do Rio de Janeiro, com propostas de melhorias para futura implanta����o de sistema de gest��o ambiental baseado nas normas ISO 14.000.

Na gest��o de recursos h��dricos, as quest��es relacionadas aos impactos ambientais causados pelas Esta����es de Tratamento de ��gua n��o podem ser negligenciadas, devendo ser avaliadas em todos seus aspectos. Neste trabalho foram avaliadas as condi����es t��cnicasoperacionais e a gest��o de seis Esta����es de Tratamento de ��gua de pequeno porte situadas nas regi��es leste e dos lagos do estado do Rio de Janeiro. Os resultados apresentam dados de produ����o de ��gua tratada, perdas de ��gua contabilizadas com lavagem de filtros e descargas de decantadores e as n��o contabilizadas, gastos de energia e produtos qu��micos, produ����o de res��duos e seu destino final, bem como levantamento da capacita����o do pessoal de opera����o, comparados com valores de literatura para ETAs consideradas eficientes. A partir da discuss��o dos resultados concluiu-se que h�� necessidade de corre����es de opera����o e manuten����o das ETAs e monitoramento da qualidade das ��guas bruta e tratada, recomendando-se que a empresa de saneamento, efetivamente, implante melhorias para uma posterior implanta����o, em cada unidade, de um sistema de gest��o ambiental, baseado nas normas ISO 14.000.

An��lise de uma iniciativa de valoriza����o de rios e lagoas em ��reas urbanas: Programa ��guas do rio (Guardi��es dos rios).

A preocupa����o com recursos h��dricos tem sido crescente em meios urbanos. O despejo de res��duos s��lidos em rios �� comum por popula����es ribeirinhas, favorecendo a ocorr��ncia de enchentes, a prolifera����o de vetores e doen��as e o desprezo da comunidade pelos rios. Nesse contexto, programas que relacionam lixo, recursos h��dricos e popula����o ribeirinha t��m sido objeto de v��rias iniciativas governamentais. Este trabalho busca avaliar uma delas: o Programa Municipal de valoriza����o de rios e lagoas ��guas do Rio (Guardi��es dos rios) que foi desenvolvido pela prefeitura do Rio de Janeiro entre abril de 2001 a mar��o de 2008. O programa buscou aliar interesses de ordem t��cnica, de sa��de p��blica e de cunho social para a comunidade por utilizar m��o de obra local para a manuten����o da calha do rio, visando �� retirada de lixo e entulhos do rio, geralmente em ��reas de pequena extens��o territorial, com manuten����o adequada de margens e entornos. A partir de entrevistas abertas e question��rios aplicados junto aos envolvidos de 27 frentes de trabalho, constatou-se um resultado bastante positivo nas comunidades onde o Programa foi implantado: diminui����o de enchentes, redu����o de vetores e melhoria da paisagem urbana. Contudo, observou-se tamb��m profundo descontentamento com a interrup����o do Programa, atribu��do principalmente ao uso indevido por determinados pol��ticos (amplia����o descontrolada do Programa com abandono de crit��rios t��cnicos) e a transfer��ncia da sua gest��o para uma institui����o municipal que n��o o manteve funcionando. Conclui-se, sobretudo, que o Programa Guardi��es dos rios �� uma iniciativa criativa de a����es emergenciais em rios urbanos, em n��vel municipal, que combina a retirada de lixo dos rios, um trabalho social e campanhas de educa����o ambiental junto ��s comunidades.

Maturity, age and growth of Oreochromis karongae (Teleostei: cichlidae) in Lake Malawi and Lake Malombe

Size-at-50% maturity, age and growth, of Oreochromis (Nyasalapia) karongae (���chambo���) in Lakes Malawi and Malombe were studied. Similar size-at-50% maturity and growth patterns were found for populations in Lake Malawi, but differences were observed for Lake Malombe populations, suggesting that current chambo fisheries management regulations, based on findings from the southern part of Lake Malawi, may be applicable to the central and southern parts of that lake, but not to Lake Malombe.

Lune Wyre & Furness Fisheries Advisory Committee 24th October, 1977

This is the report from the Lune, Wyre and Furness Fisheries Advisory Committee meeting, which was held on the 24th October, 1977. It covers fisheries income and expenditure, licence duties, and information on possible reasons for the apparent depletion of fish stocks on the River Leven. It also comments on the progress report on goosanders and mergansers and the consequent effect they were having on fisheries, net licences, erosion and a brief summary of the present situation of the development of coarse angling on Halton Fishery. Also covered is the report by the area fisheries officer on fisheries activities which includes information on fishing conditions, Skerton Weir, Forge Weir Fish Counter, fish mortalities and the construction of the fishery groynes in the River Lune. The report also includes the numbers of fish passing through counting stations at Haverthwaite and Halton, migratory fish propagation and information on the stocking of salmon and sea trout into the Kent, Leven, Crake, Duddon, Keer, Wyre and Lune watershed, and the Lakes of Windermere, Esthwaite and Grasmere watersheds. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Central Area Fisheries Advisory Committee 8th January, 1981

This is the report from the Central Area Fisheries Advisory Committee meeting, which was held on the 8th January, 1981. It covers information on the review of fisheries byelaws, netting off Flimby beach, a large fish mortality in the River Calder and Ribble, and the review of a net limitation order which was due to expire. It also includes the stocking of Worthington Lakes, Rivington Group Reservoirs and the River Wyre, the update on the proposals for the development of angling at Stocks Reservoir and the report by the area fisheries officer on fisheries activities. This comments on river conditions and fishing for salmon, sea trout and brown trout, and migratory fish movement. Also covered in the report is an update on Middleton Hatchery, salmon cages in the River Leven, Langcliffe Hatchery and the pilot hatchery, and stocking numbers of coarse fish and non migratory trout by the Angling Associations. Finally the report adds about fish mortalities, fish disease, poaching and management work. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

South Lancashire Fisheries Advisory Committee 9th January, 1980.

This is the report from the South Lancashire Fisheries Advisory Committee meeting, which was held on the 9th January 1980. The report contains sections on the minutes of the Special Meeting held on 13rd December 1979, net and fixed engine licence duties, EEC Directive on the quality of freshwaters, the market survey at Worthington Lakes, disposal of redundant reservoirs and a fisheries activities report. The section on the fisheries activities reported by the area fisheries officer looks at river conditions, fishing and migratory fish movement on Rivers Ribble and Hodder (Winckley, Waddow and Locks weir), an update on Langcliffe and Pilot Hatchery, and stocking carried out by Angling Associations and the Water Authority. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

Mersey & Weaver Fisheries Advisory Committee 9th April, 1980.

This is the report from the Mersey and Weaver Fisheries Advisory Committee meeting, which was held on the 9th April 1980. The report contains minutes of previous meetings, rod and line licence duties, the future programme for trout fisheries in the Bolton area and Commonbank Lakes. It also includes the report by the area fisheries officer which looks at river conditions and fishing, Hollingworth and Pilot Hatcheries, Worthington Stock Ponds, and stockings carried out by the Authority and Angling Associations. The Fisheries Advisory Committee was part of the Regional Water Authorities, in this case the North West Water Authority. This preceded the Environment Agency which came into existence in 1996.

South Area still waters 1995 November surveys

This is the South Area still waters 1995 November surveys from the National Rivers Authority, 1996. The report focuses on the surveys of ten Cheshire Meres (Betley, Budworth, Combermere, Hatchmere, Oak mere, Pick mere, Redes, Rostherne, Tabley, and Tatton) previously surveyed in November 1994 and May 1995. Eight others (Chapel Mere, Little Mere, Marbury Mere, Mere Mere, Oss Mere, Petty Pool, Quoisley Big Mere and Tabley Moat) were surveyed for the first time. Two other lakes, Carr Mill Dam and Pennington Flash, were surveyed. Neither of these are considered to be part of the Cheshire meres group of lakes but are of a Regional interest. This report discusses the results of the November 1995 survey before making a comparison between these and the November 1994 survey results. The section on results contains information about water column profile; nutrients (chlorophyll a; Phaeophytin; Nitrate and Nitrite; Ammonia; ortho-Phosphate; Silicate; and total Phosphorus.

Cheshire Meres 1994 November surveys

This is the Cheshire Meres 1994 November surveys report produced by the National Rivers Authority in 1995. The report focuses on some of Cheshire meres, which were showing evidence of increasing eutrophication, commonly due to anthropogenic inputs. Concern for the deterioration of the water quality of still waters has been translated by incorporating these priorities into the NRA North West Regional Environmental Strategy for Stillwaters. The meres were also being investigated as possible polluted waters under the EC Nitrate Directive. The ultimate aim is to formulate lakes management options in order to help preserve North West still waters and minimise future restoration programmes. For such pro-active work to be carried out, sufficient background data must be available. It should then be possible to fully assess the current status of these lakes, identify seasonal trends and detect significant point/diffuse pollution inputs. These surveys were the first of a series, and it was intended to repeat similar surveys in Summer and Autumn 1995, and include a further 20 meres.

The Cheshire Meres an analysis of data and a prioritisation of sites

This is a report on the Analysis of Data and a Prioritisation of Sites at the Cheshire Meres by the Institute of Freshwater Ecology. The report addresses data collected by the Agency for 24 basin sites in Cheshire. At least two samples were collected from each site, though not simultaneously. Sites were visited in May/June and in November. The determinands are standard and they included: water, temperature, conductivity, pH, DO, fractional white light penetration, TSS, chlorophyll, TP, ortho-phosphate, nitrate-, nitrite-, ammonium and silicate. Though concentrations were often higher than for other lakes in the region, rather exceeding criteria for classification as eutrophic lakes, the results confirmed that the series of lakes is, naturally, highly eutrophic and nothing in the present data differs so far from expectation that is persuasive that the ecosystems are reacting adversely to environmental stress. The data set is review and summarised, site-by-site, in an appendix. The grounds for prioritisation are discussed. Whether or not this preferred prioritised option is adopted, the Agency is recommended to review the way it carries out monitoring. The determinands and the sampling frequency need to be geared to the information that is required.

A biogeographic asssessment of seabirds, deep sea corals and ocean habitats of the New York Bight: science to support offshore spatial planning

This report provides a compilation of new maps and spatial assessments for seabirds, bathymetry, surficial sediments, deep sea corals, and oceanographic habitats in support of offshore spatial planning led by the New York Department of State Ocean and Great Lakes Program. These diverse ecological themes represent priority information gaps left by past assessments and were requested by New York to better understand and balance ocean uses and environmental conservation in the Atlantic. The main goal of this report is to translate raw ecological, geomorphological and oceanographic data into maps and assessments that can be easily used and understood by coastal managers involved in offshore spatial planning. New York plans to integrate information in this report with other ecological, geophysical and human use data to obtain a broad perspective on the ocean environment, human uses and their interactions. New York will then use this information in an ecosystem-based framework to coordinate and support decisions balancing competing demands in their offshore environment, and ultimately develop a series of amendments to New York���s federally approved Coastal Management Program. The targeted users of this report and the compiled spatial information are New York coastal managers, but other State and federal decision-makers, offshore renewable energy development interests and environmental advocates will also find the information useful. In addition, the data and approaches will be useful to regional spatial planning initiatives set up by the Mid-Atlantic Regional Council on the Ocean (MARCO) and federal regional planning bodies for coastal and marine spatial planning.