Habitat quality,not habitat amount,drives mammalian habitat use in the Brazilian Pantanal     

Regolin  André Luis  Oliveira-Santos  Luiz Gustavo  Ribeiro  Milton Cezar  Bailey  Larissa Lynn 《Landscape Ecology》2021,36(9):2519-2533

Landscape Ecology - An understanding of species-habitat relationships is required to assess the impacts of habitat fragmentation and degradation. To date, habitat modeling in fragmented landscapes...  相似文献   

Bentazone Leaching in Spanish Soils     

Esperanza Romero  Francisco Snchez-Rasero  Aranzazu Pea  Clara de la Colina  Gonzalo Dios 《Pest management science》1996,47(1):7-15

Adsorption, incubation and soil-column experiments with bentazone [3-isopropyl-1H-2,1,3-benzothiadiazin-4(3H)-one 2,2-dioxide] were carried out in ten different soils from the marches surrounding the Doñana National Park (Huelva, SW Spain). Adsorption isotherms for the different soils showed a good fit with the Freundlich equation. Bentazone was poorly adsorbed in all the soils studied, with no significant relationship between theK_f values and soil characteristics. A significant correlation was obtained between the soil organic matter content and the distribution constant values (K_d) calculated at an equilibrium concentration of 200 μg cm⁻³. The low adsorption and non-degradation of bentazone on these soils suggest that the herbicide readily percolates through soils to reach the surface and ground waters. The mobility of bentazone through three soil columns was also studied. The mass balances carried out showed that bentazone was totally eluted from the soil columns. The theoretical model applied to explain bentazone leaching under our experimental conditions seems to be suitable for soil columns with a uniform water-flow rate.  相似文献   

A two-year comparison on nutritive value and yield of eight lucerne cultivars and one red clover cultivar     

Dannylo O. Sousa  Hanne H. Hansen  Ola Hallin  Luiz G. Nussio  Elisabet Nadeau 《Grass and Forage Science》2020,75(1):76-85

Red clover (Trifolium pratense) and lucerne (Medicago sativa) are among the most common legume species used for ruminant feeding systems. Besides the greater nutritive quality and first-year ley yield compared to lucerne, red clover decreases its yield over the years. However, under unfavourable soil conditions the persistency of lucerne can be compromised, not performing as expected. This study compared yield and chemical composition of eight lucerne cultivars and one tetraploid red clover cultivar, with similar growth capacity as lucerne, replicated over two years. In the second year, four lucerne cultivars and the red clover cultivar were analysed for crude protein (CP) fractions, dry matter and neutral detergent fibre (NDF) digestibility. A randomized block design was used with three field blocks per cultivar for the multiple comparisons within each year. There were differences in DM yield, concentrations of CP and NDF and CP fractions among the lucerne cultivars, but the differences were inconsistent between years and between growth cycles within year. The red clover cultivar had lower CP and NDF concentrations than a majority of the lucerne cultivars, and greater in vitro organic matter digestibility compared to all of the lucerne cultivars. Also, the red clover cultivar had greater rumen undegradable-to-degradable CP ratio but confirmed its lower yield persistency compared to the lucerne cultivars.  相似文献   

Ovicidal lectins from Moringa oleifera and Myracrodruon urundeuva cause alterations in chorionic surface and penetrate the embryos of Aedes aegypti eggs     

Robson RV Alves  Tatiana Soares  Elinaldo FL Bento  Ricardo S Roldan‐Filho  Brbara SS Souza  Marcele KN Lima  Jssica S Nascimento  Luana CBB Coelho  Roberto A S  Thmarah A Lima  Gabriel GA Gonalves  Fbio A Brayner  Luiz C Alves  Daniela MAF Navarro  Thiago H Napoleo  Patrícia MG Paiva 《Pest management science》2020,76(2):730-736

  相似文献   

Cultivation of Agaricus bitorquis mushroom as an strategy for the Integrated Pest Management of the myceliophagous mite Microdispus lambi     

María J Navarro  Francisco R Lpez‐Serrano  Lucía A Escudero‐Colomar  Francisco J Gea 《Pest management science》2020,76(9):2953-2958

  相似文献   

Trypsin inhibitor from Enterolobium contortisiliquum seeds impairs Aedes aegypti development and enhances the activity of Bacillus thuringiensis toxins     

Pedro M S Tabosa  Luiz C P Almeida Filho  Rute X Franca  Lady Clarissa B Rocha‐Bezerra  Ilka M Vasconcelos  Ana F U Carvalho 《Pest management science》2020,76(11):3693-3701

  相似文献   

Delineating site-specific management zones on pasture soil using a probabilistic and objective model and geostatistical techniques     

Moral  Francisco J.  Rebollo  Francisco J.  Serrano  João M. 《Precision Agriculture》2020,21(3):620-636

Precision Agriculture - In recent years, different algorithms have been utilised to delineate management zones, areas with similar properties, within agricultural fields. However, there are few...  相似文献   

Litopenaeus vannamei (Boone) post-larval survival related to age, temperature, pH and ammonium concentration     

Francisco J Magallón Barajas  Rosalía Servín Villegas  Guillermo Portillo Clark  & Berenice López Moreno 《Aquaculture Research》2006,37(5):492-499

Transport of post‐larvae shrimp used in aquaculture is an important element of successful cultivation because of the potential for stress during stocking procedures. To find optimum transport conditions, several bioassays were performed in the laboratory to evaluate survival of whiteleg shrimp Litopenaeus vannamei 5–30‐day‐old postlarvae under conditions similar to those encountered during transport from the hatchery to nursery and shrimp ponds. Postlarvae were exposed for 4 h to different temperatures and pH levels ammonia concentrations. Survival was significantly reduced after a 4 h exposure to pH 9 and was inversely related to temperature with or without 7 mg L^?1 of ammonia. The 15‐ and 20‐day‐old postlarvae had higher survival rates than other ages. The lowest survival occurred in alkali conditions (pH 9), with 7 mg L^?1ammonia at 30 and 32°C. To assure optimal survival of postlarvae during transfer from the hatchery to the nursery and shrimp ponds, we recommend temperatures below 28°C, pH no higher than 8, no ammonia and post‐larval age at least 15 days.  相似文献   

Thermal preference and tolerance of green abalone Haliotis fulgens (Philippi, 1845) and pink abalone Haliotis corrugata (Gray, 1828)     

Fernando Díaz  Ana Denisse Re  Zarina Medina  Gerardo Re  Gustavo Valdez  & Francisco Valenzuela 《Aquaculture Research》2006,37(9):877-884

The thermoregulatory behaviour of green abalone Haliotis fulgens and pink abalone H. corrugata was investigated. Haliotis fulgens juveniles ranging in wet weight from 3.0 to 3.3 g and from 28.7 to 30.5 mm shell length and of H. corrugata 2.0 g and 25.7 mm in shell length were exposed to 19°C for 30 days in a flow‐through water system. Temperature preference was determined in a horizontal thermal gradient and was found to be 25.4°C for green abalone and 25.0°C for pink abalone. Displacement velocity was 4.3 cm h⁻¹ for H. fulgens and 12.8 cm h⁻¹ for H. corrugata. The optimum temperature for growth calculated for both abalone species was 24.6 and 24.5°C respectively. The critical thermal maxima (CTMax) of H. fulgens and H. corrugata were determined as a measure of thermal tolerance. Abalones were subjected to increasing water temperatures at a rate of 1°C on 30 min until they detached from the substrate. The CTMax at 50% were 33.6 and 32.0°C for green and pink abalone respectively. The results are discussed in relation to site selection and commercial rearing.  相似文献   

Functional characterization of Farfantepenaeus californiensis, Litopenaeus vannamei and L. stylirostris haemocyte separated using density gradient centrifugation   总被引：1，自引：0，他引：1  

Francisco Vargas-Albores  Teresa Gollas-Galván  & Jorge Hernández-López 《Aquaculture Research》2005,36(4):352-360

Haemocytes from penaeid shrimp (Farfantepenaeus californiensis, Litopenaeus vannamei and L. stylirostris) were separated using a discontinuous Percoll gradient. Shrimp haemocytes were spontaneously adhered to glass, allowing slide preparations for staining and microscopic differential counting. Like other crustaceans, shrimp has three main populations differing in presence and size of cytoplasmic granules and each population seems to be biochemical or functionally compromised. Prophenoloxidase (proPO )activity was mainly located in large granules haemocytes (75%) while the small granules cells participate with 25%, but seem to be responsible for encapsulation. Haemocyte discrimination ability was tested using Sephadex? (Seph?), DEAE‐Seph? and CM‐Seph?. Only DEAE‐Seph? was encapsulated by shrimp haemocytes and provoked the release of proPO activating system, indicating the role of particle charge in the activation of shrimp immune response.  相似文献