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Solos desenvolvidos em ambiente de clima semi-árido podem apresentar, naturalmente, acúmulo de sais que comprometem seu uso agrícola, o que pode ser incrementado pelo manejo inadequado da irrigação. Dependendo do uso, a degradação destes solos pode ocorrer com maior ou menor intensidade. Este trabalho teve como objetivo avaliar usos do solo utilizando atributos químicos em um perímetro irrigado na região semiárida do Nordeste do Brasil. Os usos do solo foram separados em áreas com culturas de ciclo curto (C), com fruticultura (F), com pastagem (P), áreas descartadas (D) e áreas com vegetação nativa (V). Coletaram-se amostras de solo deformadas nas camadas de 0-10, 10-30 e 30-60 cm, e indeformadas nas duas primeiras camadas para as determinações químicas e de densidade do solo, respectivamente. Os indicadores pH e condutividade elétrica do extrato de saturação, pH do solo, P disponível, C orgânico total, Ca2+, Mg2+, K+ e Na+, CTC, soma de bases (SB), percentagem de saturação por bases (V %), percentagem de Na trocável e estoque de C foram submetidos à análise multivariada, pela técnica de análise de componentes principais, e agrupamento pelo método Tocher. Os usos relacionados a sistemas produtivos apresentaram-se diferentes quanto à qualidade química do solo em relação aos atributos analisados do uso V; entre os usos relacionados a sistemas produtivos, C e D apresentaram qualidade química mais semelhante, o mesmo ocorrendo para os usos C e P. Em relação ao uso V, os usos C, D, P e F apresentaram, nas três camadas analisadas, maiores valores dos atributos pHs, pH do extrato de saturação, condutividade elétrica do extrato de saturação, Ca e Mg trocáveis, SB, V % e P disponível. Os usos F e P apresentaram o menor teor de C orgânico total. Os usos C, D e P apresentaram maiores valores de condutividade elétrica do extrato saturado em comparação com os usos F e V, indicando o início de um processo de salinização do solo, tornando suas utilizações agrícolas menos sustentáveis. Soils developed at semi-arid climate can present salt accumulation, which compromise the agricultural use, being increased by inadequate irrigation management. Based on the use, the degradation of these soils can occur at higher or smaller intensity. This study aimed to evaluate the effect of soil uses based on physical and chemical properties of an irrigated area in the semi-arid region of northeastern Brazil. The soil uses were annual crops (C), fruticulture (F), pasture (P), discarded lands (D), or native vegetation (V). Disturbed soil samples were collected from the 0-10, 10-30 and 30-60 cm layers for chemical analysis, and undisturbed samples from the first two layers for soil density analysis. The indicators pH and electrical conductivity of the saturation extract, soil pH, available phosphorus, total organic carbon, exchangeable cations, calcium, magnesium, potassium, and sodium, cation exchange capacity, sum of bases, base saturation percentage, percentage of exchangeable sodium, and carbon stocks were subjected to multivariate analysis by Principal Component Analysis, and clustering by the Tocher method. The soil chemical properties under production systems was different from V; the chemical quality of the production systems C and D, and that of C and P was similar. For the uses C, D, P, and F, the values of the soil properties (pH, pH and electrical conductivity of the saturation extract, exchangeable calcium and magnesium, sum of bases, base saturation and available phosphorus) was higher than for V in the three analyzed layers. The highest total organic carbon content was observed under F and P. The electrical conductivity of the saturation extract was higher under C, D and P than under F and V, indicating the beginning of a soil salinization process, thus characterizing them as less sustainable land uses.

It is often suggested that diverse communities are less likely to be invaded, but both negative and positive relationships, between native flora richness and invasion, have been reported. Invaders may induce differential impacts on various native species, resulting in fundamental changes in community structure. Within the framework of the ALIEN IMPACT project we investigated the patterns of impact of seven highly invasive species (four terrestrial and three aquatic species) on native plant species richness, structure and composition in Belgium, with a particular focus on sites of high biological value. Our results showed similar patterns of impact following invasion, both for terrestrial and aquatic communities. The four terrestrial target species tended to invade diverse habitats or vegetation communities. Disturbances appeared to be the main cause of invaders establishment. The reduction in native plant richness/diversity was a common pattern to invasion. However, the magnitude of impacts were species specific. No endangered species or species of concern was found to be directly impacted by invasion. The three aquatic target species could invade ponds with a broad range of nutrient levels. Invaded ponds, regardless of the alien species, supported a lower native plant richness/diversity compared to adjacent non-invaded ponds. Submerged vegetation is the most threatened by the invasion because alien species tend to occupy a large amount of space. Indirect consequences on whole communities should be further studied and taken into account in order to produce an integrated ranking of HIPS impacts.

Con el objeto de estudiar la producción de hojarasca de la vegetación nativa en los llanos altos centrales de Venezuela, zona de vida de bosque seco tropical, se desarrolló el presente trabajo. El muestreo fue estratificado por tipos de vegetación: bosque (B), arbustal (A) y sabana arbolada (S). Se delimitaron seis transectas de 400 m². La transecta se dividió en cuatro parcelas de 100 m² cada una. Se distribuyeron uniformemente a lo largo del transecto 12 colectores de 0,25 m² cada uno. El material capturado por las trampas se retiró una vez al mes, durante un año (2004-2005). La producción de hojarasca fue 6.101, 3.829 y 3.606 kg de MS/ha/año para la vegetación de B, A y S, respectivamente. El análisis de varianza mostró diferencias muy marcadas (P=0,001) entre los tipos de vegetación. Entre bosque y arbustal y entre bosque y sabana existieron diferencias muy significativas (P0,10). La hojarasca se produjo durante todo el año, con máximos en los meses de final de año y mínimos al inicio del mismo. Los resultados indicaron que las áreas de bosque y arbustal y bosque y sabana presentaron poca o ninguna similitud en cuanto a la producción de hojarasca. La dinámica en la producción de hojarasca sigue un patrón determinado por la época del año y constituye una fracción importante de biomasa en los tres ecosistemas. In order to carrying out a study of the litter production of the native vegetation at the high central llanos of Venezuela, a tropical dry forest, the present work was developed. The sampling was stratified by types of vegetation: forest (F), shrubland (Sh), and savanna tree-covered (Sa). Six transects of 400 m² were defined. The transect was divided into four plots of 100 m² each one. Twelve litter collectors 0.25 m² were evenly distributed along the transects. The material captured by the traps was retired once a month, during a year (2004-2005). The litter production was 6.101, 3.829, and 3.606 kg MS/ha/year for F, Sh, and Sa, respectively. The variance analysis showed highly significant differences (P=0.001) among vegetation types. Highly significant differences existed (P0.10). Litter production took place during the whole year, with maximum at the last months of the year and minimum at the beginning of the year. The results indicated that the forest and shrubland areas, and forest and savanna presented little or no similarity for litter production. The dynamics in the litter production followed a pattern determined by season of the year and it constitutes an important fraction of biomass in all three ecosystems.

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior As vespas sociais são insetos predadores que se alimentam, principalmente de lagartas, o que revela seu potencial para o controle biológico. A primeira etapa de programas de manejo integrado de pragas é conhecer as espécies em determinado sistema. Portanto o objetivo desse estudo foi identificar as espécies de vespas sociais capturadas em eucaliptal e testar diferentes métodos de amostragem. Doze coletas mensais foram realizadas em plantio de eucalipto em Coronel Pacheco, Minas Gerais, com duas metodologias: busca ativa nas trilhas e plantio (vespas coletadas com rede entomológica) e armadilhas atrativas (feitas com garrafas “pet” de dois litros, com aberturas laterais) presas ao tronco do eucalipto a aproximadamente 1,5m de altitude do solo. Nestas eram colocados 150ml de substrato atrativo: suco de maracujá ou goiaba (fruta, água e açúcar) ou caldo de sardinha (sardinha em conserva e água). Trinta e seis garrafas (12 garrafas por substrato) foram utilizadas por coletas em quatro transectos retilíneos de 80m (T1 e T2- mata-eucalipto; T3 e T4- eucaliptal), cada um contendo nove armadilhas, distantes 10 metros. Os dados climáticos (temperatura e precipitação) foram obtidos na estação meteorológica da EMBRAPA Gado e Leite em Coronel Pacheco, Minas Gerais. Doze espécies de vespas sociais de seis gêneros foram identificadas. Por meio da busca ativa 10 espécies foram coletadas e as armadilhas seis. A busca ativa registrou a maior diversidade (H’= 0,83), seguida das armadilhas atrativas com maracujá (H’= 0,38), goiaba (H’= 0,29) e sardinha (H’= 0,18). O índice de eficiência foi maior com a xvi busca ativa (83,3%). O número de espécies foi maior nos transectos de borda (T1 e T2), próximos à mata nativa. Cinqüenta por cento das espécies coletadas foram acidentais, 33% acessórias e 17% constantes. As espécies de vespas sociais não apresentaram correlação com as variáveis climáticas (temperatura e precipitação), mas espécies enxameantes foram registradas durante todos os meses de coleta e aquelas de fundação independente não foram obtidas nos meses de janeiro e junho. A melhor metodologia é a combinação de duas ou mais técnicas, pois nenhum método registrou sozinho todas espécies de vespas. A manutenção de faixas de vegetação nativas nas proximidades do eucalipto, como uma estratégia de favorecer a ocorrência natural das espécies de vespas sociais é importante. Todas as estações do ano são favoráveis para o manejo de vespas sociais em eucaliptais, principalmente, para espécies enxameantes. The social wasps are predators of many insect species, mainly caterpillars, which shows their potential for programs of biological pest control. The first stage of the these programs is to identify species found in a particular system. Twelve monthly samples were made at eucalyptus plantation in Coronel Pacheco, Minas Gerais States Brazil, with two methods: active search on trails and the plantation (wasps collected with entomological net) and attractive traps (made with two-liter "pet" bottles, with a lateral opening) tied to eucalyptus trunk at approximately 1.5m high above the ground. One hundred and fifty ml attraction substrate was put: passion fruit juice or guava juice (fruit, water and sugar) or broth of sardines (sardines preserved and water). Thirty six bottles was used for collection (12 bottles for each substrate) in four transects of 80m (T1 and T2 - forest-eucalyptus; T3 and T4 - eucalyptus plantation), each with nine traps, distant one from another 10m. Climates data (temperature and precipitation) was obtained from the meteorological station of EMBRAPA Cattle and Milk in Coronel Pacheco. Twelve species of social wasps of six genera were identified. The active search sample method collected 10 species and six in the traps. The active search obtaining the greatest diversity (H' = 0.83), followed by attractive traps with passion fruit juice (H' = 0.38), guava juice (H'= 0.29) and sardines (H' = 0.18). The active search (83.3%) brad higher efficiency. was The greatest number of species occurred in transects of edge (T1 and T2), next to the native forest. There was no correlation between the social wasps species xviii and climatic variables (temperature and precipitation), but swarm-founding species have been recorded during every month of collection and independent foundation were not obtained in January and June. Those with, the best methodology is the combination of two or more techniques, since a specific methodology did not all species collected. It is important to maintain fragments of native vegetation nearly eucalyptus plantations, as a strategy to increase natural occurrence of species social wasp. All seasons are favorable to manage social wasp in eucalyptus plantation, especially for swarm-founding species.

Metadata only record The project objectives are to: PES-1 (Payments for Environmental Services Associate Award)

Metadata only record The ecosystem services project goals: PES-1 (Payments for Environmental Services Associate Award)

Metadata only record This case study will examine the economic tradeoffs involved between implementing pollution mitigation strategies on farmland and the treatment costs for downstream consumers. As a result, minimum value estimate of the native vegetations filtering capacity will be provided. PES-1 (Payments for Environmental Services Associate Award)

The invasion of a target community by a non-indigenous plant species includes the stages of arrival, establishment and spread, which tend to depend on different characteristics of the invasive species and its context. While the mechanisms behind the invasion of highly disturbed ecosystems are well known, our understanding of the invasion process in undisturbed or weakly disturbed ecosystems is much more limited. Here we propose that, once a non-indigenous species has arrived to a new ecosystem and become established, the likelihood that it spreads, and thus becomes invasive, may depend on just one or very few characteristics, called‘triggering attributes’(TA). We propose that a TA is a vegetative or regenerative attribute discontinuously distributed in comparison to the resident community. This attribute allows the species to benefit from a resource that is permanently or temporarily unused by the resident community. We present an original study case and examples from the literature to illustrate our approach, and we also propose some ways to test it in different ecosystems. Fil: Gurvich, Diego Ezequiel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Tecco, Paula Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina Fil: Díaz, Sandra Myrna. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina

An investigation was conducted to study the relationships between soil organic carbon and thoseproperties that may influence carbon accumulation in soils derived from volcanic ash through a rangeof bio-climatic conditions at the Andinopatagonian region in SW Neuquén, Argentina. Pedon andclimatic data of nineteen plots were used and grouped, through principal component analysis, by soilhydric regime –udic group (U) and xeric group (X)-. Within each group, a simple and a multipleregression analysis was carried out between organic C -content (t ha-1) or concentration (g kg-1)- andmean annual precipitation, bulk density, pH(H2O) and pH(NaF), oxalate extractable Al (Alo), pyro-phosphate-extractable Al (Alp), Alp/Alo, and Alo-Alp –the last four so as content or as concentra-tion. Mean annual precipitation, explained little variation in soil organic carbon in both groups (R2 =20), and bulk density was unrelated to soil organic carbon. Alp correlated strongly with organic Ccontent in both groups (U: R2 = 0.67, p

The Native Vegetation Conservation Act was introduced on January 1st 1998 to limit the clearing of native grassland and woodland in NSW. The Act has limited clearing and development to crops, has protected biodiversity, and may have enhanced soil and water conservation. But this analysis of the prices paid for land in Moree Plains Shire shows that the Act has reduced land values by some 21 per cent and has already reduced annual incomes by 10 per cent across the whole Shire. This reduction in annual incomes may well reach 18 per cent by 2005. This decrease in income means that farm households in the Shire currently must give up 15.6 per cent of their household income because they must protect native vegetation on their farms. In contrast, urban households in Australia must give up only 0.55 per cent of one per cent of their income through taxes for the same purpose. The Act has imposed these costs on farmers who are already struggling financially, has made the distribution of income in the community less equal, and has made farm families bear far higher costs than urban families. Do these outcomes enhance an objective of equity, or fairness within the community?

Australian policies to preserve native vegetation on farms rest on mandatory regulations without compensation, whereas policies in most OECD countries rest on voluntary conservation with compensation. In New South Wales, the Native Vegetation Conservation Act 1998 restricts farmers from clearing native vegetation on their own freehold land, and offers no compensation. The Act may therefore impose opportunity costs, or losses in income, on landholders. These opportunity costs are estimated for a case study property in the Hunter Valley of New South Wales, and these results are then generalised to assess the broad trade-offs between development and preservation. The losses in income appear to vary between 5 and 10 per cent of annual income, depending on livestock prices. The flow of these losses over time appears to total some $26m for all properties of this kind in the immediate region. In addition to imposition of these direct opportunity costs, the regulations hinder land sales and so hinder adjustment by landholders to changing conditions.

Made available in DSpace on 2013-09-27T14:53:33Z (GMT). No. of bitstreams: 1 WOS000290327200011.pdf: 281186 bytes, checksum: 1a4561713136d422101945a1e2ec00bb (MD5) Previous issue date: 2011-01-01 Made available in DSpace on 2013-09-30T18:00:01Z (GMT). No. of bitstreams: 1 WOS000290327200011.pdf: 281186 bytes, checksum: 1a4561713136d422101945a1e2ec00bb (MD5) Previous issue date: 2011-01-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:17:29Z No. of bitstreams: 1 WOS000290327200011.pdf: 281186 bytes, checksum: 1a4561713136d422101945a1e2ec00bb (MD5) Made available in DSpace on 2014-05-20T13:17:29Z (GMT). No. of bitstreams: 1 WOS000290327200011.pdf: 281186 bytes, checksum: 1a4561713136d422101945a1e2ec00bb (MD5) Previous issue date: 2011-01-01 The determination of the amount of sample units that will compose the sample express the optimization of the workforce, and reduce errors inherent in the report of recommendation and evaluation of soil fertility. This study aimed to determine in three systems use and soil management, the numbers of units samples design, needed to form the composed sample, for evaluation of soil fertility. It was concluded that the number of sample units needed to compose the composed sample to determination the attributes of organic matter, pH, P, K, Ca, Mg, Al and H+Al and base saturation of soil vary by use and soil management and error acceptable to the mean estimate. For the same depth of collected, increasing the number of sample units, reduced the percentage error in estimating the average, allowing the recommendation of 14, 14 and 11 sample in management with native vegetation, pasture cultivation and corn, respectively, for a error 20% on the mean estimate. Univ Estadual Paulista, UNESP, Fac Ciencias Agr & Vet Jaboticabal, Dept Solos & Adubos,FCAV, BR-14884900 Jaboticabal, SP, Brazil Univ São Paulo, Dept Zootecnia 225, BR-13635900 Pirassununga, SP, Brazil Univ Estadual Paulista, FCAV, Fac Ciencias Agr & Vet Jabotica, Dept Ciencias Exatas, São Paulo, Brazil Univ Estadual Paulista, UNESP, Fac Ciencias Agr & Vet Jaboticabal, Dept Solos & Adubos,FCAV, BR-14884900 Jaboticabal, SP, Brazil Univ Estadual Paulista, FCAV, Fac Ciencias Agr & Vet Jabotica, Dept Ciencias Exatas, São Paulo, Brazil

Vegetation fires burnt an average 200,000 ha annually in the Mediterranean Basin between 1960 and 1970 ; the figure attained over 400,000 ha in the 1970’s and over 600,000 ha in the 1980's. This three fold increase over 20 years is turning into an annual summer-catastrophe in the Basin, in spite of heavy investments and large budget expenditure spent to prevent and combat the scourge. The paper gives detailed figures of number and acreage of fires in the various countries of the Basin, analyses the causes and evolutionary trends ; some further regional details are provided for southern France. The cost of preventing and combatting vegetation wild fires is evaluated for each country. The global cost for the Basin is in the vicinity of one billion U.S.$, as an annual average in the 1980's. But this figure does not take into account a number of havocs which are difficult to quantify such as : erosion, sedimentation, the silting up of reservoirs, floodings, loss of nutrients, hence decrease of fertility and productivity ; loss of wildlife and game, of amenities and aesthetic value, etc. The author advocates an expansion of research, demonstration and education of the public and politicians on the use of prescribed burning in conjunction with the systematic utilisation of browsing animals (cervidae, goats, camelidae) in order to reduce the fuel buildup, hence fire hazards and the ever increasing financial burden on rural communities , not to speak of losses in human life., Le Houérou Henri Noël. Vegetation wild fires in the mediterranean basin: evolution and trends. In: Ecologia mediterranea, tome 13 n°4, 1987. Influence of fire on the stability of mediterranean forest ecosystems. Giens (France) 23-26/03/1987. pp. 13-24.