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Highlights: [•] Both suitable foraging and roosting areas determined rice fields’ quality for godwits. [•] Godwits minimised their daily movements between roosting and feeding areas. [•] Home range core areas were centred on the roosts. [•] Power lines was the most important landscape factor affecting godwits’ roosts’ location. [ABSTRACT FROM AUTHOR]

This article is based on the summary of a work being developed in Peru by the Ministry of Health, regarding implementation of the alternate wet and dry irrigation technique for rice fields, especially in zones with a higher incidence of malaria and lower availability of water for agriculture. The study explains the incidence of malaria on a world level and in Peru, its relation to rice fields, the expense this health problem represents for the Peruvian State and the importance of including citizen participation, especially those most affected, in the search for solutions. Like wise, the paper explains actions carried out through the participation of technical and official organizations and in habitants of the zone where the project was developed. Project results of applying an alternate wet and dry irrigation system to control the malaria vector are high lighted for the Pítipo District in the Lambye que Region, during the 2008-2010 period, especially those results related to the perceptions of rural farmers in the zone, as well as sustain ability strategies for the project in the future. [ABSTRACT FROM AUTHOR]

Highlights: [•] We perform long-term analysis of non-breeding counts of black-tailed godwits in Doñana. [•] Increasing numbers in winter was observed, but not changes in spring migration. [•] Increase in man-made artificial wetlands were associated to increasing godwits numbers. [•] Man-made habitats need to be considered in conservation plans for the species. [ABSTRACT FROM AUTHOR]

Agri-environment schemes (AES) favouring the maintenance of hedges were implemented in the Camargue (southern France) as it has previously been proven to reduce the risk of damage caused by Greater Flamingo incursions into rice fields. Given the persistent incursions, we estimated the economic cost of damage from 2007 to 2009, the uptake rate of hedge-related AES and explored the limits of these schemes as a mitigation effort. Semi-structured and key informant interviews, site mapping and field visits were made to verify claims and estimate damage. Number of plants/m2and fertile stems/plant were estimated on 1,498 and 312 grids, respectively, spread over 26 rice fields. Damaged areas of rice fields forayed by flamingos presented from 1.35 to 3.06 t/ha lower yield than undamaged areas. We estimated 228€/ha average loss in forayed fields for a total of 400,000€ in yield loss in 2008. Administrative constraints limited AES and free seedlings distribution, preventing the problem from being addressed at an appropriate scale. The trivial financial support for hedge management relative to more lucrative AES with lower constraints resulted in low uptake rate. We propose that modifications of AES take into account landscape factors over administrative boundaries and that the financial support for AES be scaled up relative to other subsidies in order to address the efforts necessary to achieve landscape changes to reduce human–wildlife conflict. [ABSTRACT FROM PUBLISHER]

Background: A few elements of soil are radioactive. Soil can transfer radionuclide into plants feeding human. Sometimes their levels are as high as to be concern of human healthy. Rice has an important share for Iranian foods especially in north of Iran. Therefore we decided to obtain radionuclides concentration emitting g rays in Lahijan City (Northern Iran) rice fields using g spectroscopy. Methods: Twenty eight samples from rice field's soils and 12 samples from superficial soils were collected at a square of 10*10 m2 to get 2kg weight. To make dry samples were put into oven at 105oC for 24h. Then they were milled and 950 gr of each sample was transferred to Marinelli container with 1000cc volume, sealed and left for 40 days to get secular equilibrium. After measuring Ph, Electric conductivity and organic carbon, g spectroscopy was done to get sample gamma spectrum at 2000-6000 sec using HpGe detector. Results: It was found 226Ra activity in rice fields of 29.273±0.72 Bqkg-1 and city soil of 31.02±1.1 Bqkg-1 and also 232Th activity of 37.47±1.12 Bqkg-1 for rice fields' soils and 40.47±1.68 Bqkg-1 for city soil were in standard mode. Conclusion: 40K activities mean value according to UNSCEAR; 2000 was found a little greater than standard. A little value of 137Cs was found in Lahijan rice fields and city soils that could be as a result of Chernobyl accident. In except of 137Cs, for three other under studied city soil elements, activities were greater than that of rice fields.

Abstract The Panel considers the Spanish pest risk analysis (PRA) to be clear and to provide appropriate supporting evidence. However, (i) the environmental impact assessment is incomplete and (ii) the estimates for the potentially endangered area are too limited. The Panel points out that large areas of the European Union have climatic conditions, that are very similar to those of the areas of native distribution of Pomacea spp. snails, and suitable host plants are available. The Panel agrees with the Spanish PRA on the following points with regard to the risk assessment area: (i) the potential consequences of the organism for rice crops are major; (ii) the probability for establishment of the organism is very likely and (iii) the probability of spread is estimated as likely. The Panel disagrees with the Spanish PRA on the following points and considers (i) the effects on the environment to be massive under suitable environmental conditions in the PRA area and (ii) the probability of entry of the organism to be high. Regarding risk reduction options the Panel agrees with the Spanish PRA that no single risk reduction method is sufficient to halt the introduction and spread of Pomacea spp. snails in the PRA area. However, a legislative ban on import of Pomacea spp. is the only risk reduction option identified that can reduce the probability of entry. The many other risk reduction options listed will help to reduce the probability of spread within the PRA area. The Panel considers that the risk reduction options should target the canaliculata complex, as Pomacea insularum and P. canaliculata, as well as other species from the complex, are almost indistinguishable. This is of particular importance for risk reduction options addressing both breeding and trade of the organism.

Although rice production landscapes are often the scene of homicides, vertebrate decomposition and associated arthropods have never been described from rice paddies. Tropical rice landscapes are typically composed of irrigated/non-irrigated rice fields, fallow land (i.e., uncultivated fields), and low earthen levees (bunds) used as access pathways. The specific microclimatic and environmental conditions associated with each subunit of rice field landscapes are likely to impact carcass decomposition as well as the arthropod species associated with carrion. Here, we tested the hypothesis that the combined effects of constraints on arthropod colonization and survival, scarcity of necromass, limited habitat architecture, and recurrent disturbance limit the ability of carrion-related arthropods to colonize corpses and large carcasses in tropical rice-fields. Our results from monitoring pig carcasses in Philippine rice fields indicated that vertebrate decomposition in irrigated fields was slower and incomplete when compared to non-irrigated fields and bunds. Carcasses were colonized by a small complex of carrion-related arthropods that differed in composition and relative species abundance between dry bunds and relatively humid rice paddies. Fire ants (Solenopsis germinata) were observed frequently on carcasses exposed on bunds, rarely in non-irrigated fields, and almost never in irrigated fields. The presence of fire ants was associated with reduced blow fly (Chrysomya megacephala) abundance. Taken together, this indicates that the arthropod fauna associated with carcasses in tropical rice fields is relatively simple in contrast to the generally high arthropod diversity reported for other ecosystems at tropical latitudes. The limited richness of the community also means that an understanding of the development of one abundant calliphorid blow fly, C. megacephala, may be sufficient to investigate deaths and homicides under conditions similar to the ones described in this study. [ABSTRACT FROM AUTHOR]

Background In Vietnam, paddy rice fields have been identified as a major non-point source of pesticide pollution of surface- and groundwater which is often directly used for domestic purposes. One strategy to assess the risk of pesticide pollution is to use process-based models. Here, we present a new model developed for simulating short-term pesticide dynamics in combined paddy rice field-fish pond farming systems. The model was calibrated using the Gauss-Marquardt-Levenberg algorithm and validated against measured pesticide concentrations of a paddy field-fish pond system typical for northern Vietnam. Results In the calibration period, model efficiencies were 0.82 for dimethoate and 0.87 for fenitrothion. In the validation period, modelling efficiencies slightly decreased to 0.42 and 0.76 for dimethoate and fenitrothion, respectively. Scenario simulations revealed that a field closure period of 1 day after pesticide application considerably reduces the risk of pond and surface water pollution. Conclusion These results indicate that the proposed model is an effective tool to assess and evaluate management strategies, such as extended field closure periods, aiming to reduce the loss of pesticides from paddy fields. © 2013 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The great sensitivity of amphibians to land disturbance is one of the main causes that contributed to their worldwide decline. One fundamental approach in assessing amphibian ability to reflect habitat degradation is to measure their phenotypic changes in contrasting environments. We examined the extent to which several morphological traits of the endemic anuran Pelophylax perezi responded to agricultural conversion in Monegros, an arid region in NE Spain. Specifically, we determined how body size, body mass, body condition (BC) and fluctuating asymmetry (FA) of different frog classes varied among habitats with different degree of management, i.e. rice fields vs. control ponds (i.e. small reservoirs). Pelophylax perezi juveniles showed a decrease in size and mass in rice fields, revealing that early life stages are generally more susceptible to habitat alteration. Adult body condition, on the other hand, increased significantly in cultivated habitats, which apparently indicates a good fitness in this size class. Nonetheless, skeletal asymmetry of both, juveniles and adults was significantly higher in rice fields. Moreover, during postmetamorphic development FA increased significantly towards adult stage indicating that the development controlling mechanisms were not able to buffer the stress induced by land use change. Among traits, humerus, radio-ulna and metatarsal were highly sensitive in terms of expressing significant FA differences between habitats, contrary to tibio-fibula, whose precise symmetry is essential for animal locomotion. The former bones have therefore the potential to be used as sensitive indicators of stress in amphibians. FA showed no relationship with body condition. This, together with the previous results demonstrates that FA is able to capture habitat stress more reliably than the morphological estimates such as body size, mass and BC. Therefore, FA is a useful morphological tool, highly recommended to monitor stress levels in amphibian populations. [ABSTRACT FROM AUTHOR]

BACKGROUND: Multimammate mice are the most important vertebrate pests in Sub-Saharan Africa and are also reservoirs of many zoonotic diseases, including sylvan plague. This study investigated the population dynamics and breeding patterns of this mouse in irrigated rice cropping systems in eastern Tanzania. RESULTS: The multimammate mouse, Mastomys natalensis, population varied with habitat and months. Fallow land had a more abundant population than rice fields. The highest population peak was observed during the dry season from July to October. Mastomys natalensis is sexually active throughout the year in the study area, although it reaches the highest level in June and December when rice is at the maturity stage. This suggests that breeding is highly influenced by the presence of a rice crop in both seasons. More juvenile individuals were recorded in August and September, indicating that they were produced in the previous breeding months. The sex ratio of M. natalensis was not skewed to either males or females, indicating that it was at parity. CONCLUSION: Rodent population dynamics during the study periods in all habitats indicated that high birth rates accounted for the rapid population growth and turnover. Regular control and sustainable operations are thus essential if rodent pest populations are to be kept within tolerable limits. © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this study, we evaluate spatial and temporal variations of the water's quality used in rice fields. Every 15 days during the different phases of cultivation of the rice—vegetative, reproductive, and maturity—samples were collected from the main irrigation channel, from the surface water in the field, and from the excess-water drainage channel. The differences in the values of 13 variables were analyzed by the analysis of variance system and by the Principal Component Analysis (PCA) technique. The results demonstrate that the values observed for the presence of total coliforms, heat-tolerant coliforms, and pH were higher in the irrigation water and that the calcium and magnesium components were greater in the drainage water. The PCA results indicate that three groups of variance exist and that these three account for 77 % of the observed variances. The first principal component, (39 % of the variances), includes the variables pH, phosphorus, potassium, carbon, and turbidity; the second (28.1 %), calcium, magnesium, and conductivity; while the third accounts for only 9.9 % of the variation and incorporates the variable biological thermotolerant coliforms. The spatial pattern resulting from the distribution of the sampling locations as regards the first two principal components indicates a difference between the irrigation and drainage waters. The variables of the first and third items (except for the turbidity in the second component) reach higher values in the irrigation water, while the variables associated with the second component have higher values in the drainage water. The information provided is important for the analysis of the influence exercised by plantation management decisions on the microbiological, physical, and chemical quality of the water. The results confirm the ability of paddy rice field to filter out some of the chemicals and coliforms from the irrigation water as it passes through the agro ecosystem. [ABSTRACT FROM AUTHOR]

Methane (CH) emission and water productivity were estimated in an experiment conducted during wet (rainy) season of 2010 at the research farm of Indian Agricultural Research Institute, New Delhi, India. Treatments comprising three methods of crop establishment viz., conventional transplanting (CT), system of rice intensification (SRI) and double transplanting (DT) were laid out in randomized block design with four replications. Scented rice ( Oryza sativa L) variety 'Pusa Basmati 1401' was transplanted in puddle field. In CT and SRI 21 and 12-day-old seedlings, respectively, were transplanted while in DT overall 45-day-old seedlings were transplanted. In CT and DT flooded conditions while in SRI saturated conditions were maintained. Results indicated that among the methods of crop establishment, CT had maximum cumulative CH emission (32.33 kg ha) followed by DT (29.30 kg ha) and SRI (19.93 kg ha). Temporal CH flux fluctuated between 79.7 and 482.0 mg m day under CT; 46.0 and 315.0 mg m day in SRI and 86.7 and 467.3 mg m day in DT. Considerable temporal variations in the individual CH fluxes were observed. Flux of CH was generally higher in early stage of crop and peaked about 21 days after transplanting coinciding with tillering stage of crop. CH flux declined gradually from 75 days after transplanting and stabilized at the harvest stage of rice in all the three methods of transplanting. Global warming potential was highest in CT (807.4 kg CO ha) and lowest in SRI (498.25 kg CO ha). However, a reverse trend was observed with carbon efficiency ratio. The water savings to the extent of six irrigations was recorded in SRI over CT. A saving of 27.4 % irrigation water and 18.5 % total water was recorded in SRI over CT while the corresponding values of DT over CT were 14.5 and 9.8 %. Water productivity of SRI (3.56 kg/ha mm) was significantly higher as compared to DT (2.87 kg/ha mm) and CT (2.61 kg/ha mm). [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the potential risk of pretilachlor, thiobencarb, and propanil pollutants in the water system of the rice fields of the Muda area. The study included two areas that used different irrigation systems namely non-recycled (N-RCL) and recycled (RCL) water. Regular water sampling was carried out at the drainage canals during the weeding period from September to October 2006 in the main season of 2006/2007 and April-May 2007 in off season of 2007. The herbicides were extracted by the solid-phase extraction method and identified using a GC-ECD. Results showed that the procedure for identification of the three herbicides was acceptable based on the recovery test values, which ranged from 84.1% to 96.9%. A wide distribution pattern where more than 79% of the water samples contained the herbicide pollutants was observed at both the areas where N-RCL and RCL water was supplied for the two seasons. During September to October 2006, high weedicide residue concentration was observed at the N-RCL area and it ranged from 0.05 to 1.00 μg/L for pretilachlor and propanil and 10-25 μg/L for thiobencarb. In the case of the area with RCL water, the weedicide residue ranged from 1 to 5 μg/L for pretilachlor and propanil and 10-25 μg/L for thiobencarb. The highest residue level reached was 25-50, 50-100, and 100-200 μg/L for pretilachlor, propanil, and thiobencarb, respectively. During April to May 2007, high residue concentration frequently occurred at the area supplied with N-RCL irrigation water and it ranged from 0.05 to 1.00, 10 to 25, and 25 to 50 μg/L for pretilachlor, propanil, and thiobencarb, respectively. The highest residue level reached was 25-50 μg/L for pretilachlor and 100-200 μg/L for propanil and thiobencarb. There was an accelerated increase in the concentration of the herbicide residues, with the maximum levels reached at the early period of weedicide application, followed by a sharp decrease after the rice fields were completely covered with the rice crop. During the main season of 2006/2007, the concentration of propanil residue gradually rose, although that of the other herbicides declined. [ABSTRACT FROM AUTHOR]

Abstract: A knowledge of the foraging strategies of marine predators is essential to understand the intrinsic factors controlling their distribution, abundance and their ecological function within the marine ecosystem. Here, we investigated for the first time the foraging movements and activity patterns of Audouin’s gull Larus audouinii by using satellite-tracking data from eight breeding adults in the main colony of the species worldwide (Ebro Delta, NW Mediterranean). Tagged gulls foraged in the marine area close to the breeding colony (62% of foraging locations) and in the terrestrial area of the Ebro Delta (mainly rice fields; 38% of foraging locations). The foraging activity patterns changed significantly throughout the day; lower from dusk through the first half of the night (19-1 h; 32% of active locations) and higher during the rest of the day (1–19 h; 75.5 ± 4.3% of active locations). These results confirm the foraging plasticity of this seabird and, based on previous information about the dietary habits of this species, we hypothesize how its time-dependent activity patterns and habitat use could be associated with variations in the availability of marine food resources (e.g. diel vertical migrations of pelagic fish) and the exploitation of terrestrial resources (e.g. American crayfish Procambarus clarkii). [Copyright &y& Elsevier]

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Amphibian predator-insect prey relationships are common in terrestrial habitats, but amphibian larvae are preyed upon by a variety of aquatic hemipterans in aquatic habitats. This paper suggests that the survival of the nymphs of the endangered aquatic hemipteran Kirkaldyia (=Lethocerus) deyrolli (Belostomatidae: Heteroptera) is directly and indirectly affected by the abundance of their amphibian larval prey (tadpoles). Young nymphs of K. deyrolli mainly feed on tadpoles, regardless of differences in prey availability. Nymphs provided with tadpoles grow faster than nymphs provided with invertebrate prey. Therefore, tadpole consumption seems to be required to allow the nymphs to complete their larval development. In addition, the survival of K. deyrolli nymphs was greater during the period of highest tadpole density (June) than during a period of low tadpole density (July). Higher tadpole density moderates predation pressure from the water scorpion Laccotrephes japonensis (Nepidae: Heteroptera) on K. deyrolli nymphs; i.e., it has a density-mediated indirect effect. These results suggest that an abundance of tadpoles in June provides food for K. deyrolli nymphs (a direct bottom-up effect) and moderates the predation pressure from L. japonensis (an indirect bottom-up effect). An abundance of amphibian prey is indispensable for the conservation of this endangered giant water bug species. [ABSTRACT FROM AUTHOR]

The study was carried out by tree visits in different areas of the Natura 2000 site "Rice Fields Tsalapitsa" BG 0002086 (West of Plovdiv city, near village of Tsalapitsa). Our preliminary research showed that in the area vertebrates with high conservation status occurred included in the Bulgari an Bidiversity Act, Appendix II and III, Appendix II of the Bern convention, Natura 2000 species list, the Bonn convention, Appendix II, the Convention of the International Trade of Endangered Species, and the list of the International Union for Conservation of the Nature. This information will help in future preparation of the management plan of the Natura 2000 site and showed the need of studies focused on such areas which will help undertaking adequate measures for their proper way of conservation. [ABSTRACT FROM AUTHOR]

The effects of straw burning, exposure conditions and exposure durations on the diversity of zooplankton resting eggs were examined by hatching resting eggs in sediment collected from rice fields in Pathum Thani province, Thailand. Well-mixed surface sediment samples from with- and without straw burning paddies were stored under three conditions, (4°C and darkness; 28-40°C and darkness; and 28-40°C and light), for different periods of time (0, 2, 4, 6, 8, 10 and 12 months). Thirty zooplankton species were identified from hatching experiments. Of these, 25 species were Rotifera, 3 were Cladocera, 1 was Ostracoda and 1 was Copepoda. Repeated Measurement analysis showed that straw burning significantly decreased the number of zooplankton species, the zooplankton abundance and zooplankton diversity ( P = 0.000, 0.019 and 0.004, respectively). A significant effect of storage conditions on the number of species was also present ( P = 0.016), whereas zooplankton abundance and zooplankton diversity were not affected ( P = 0.583 and 0.180). In addition, exposure time had an effect on number of zooplankton species and diversity ( P = 0.001 and 0.033) but not on zooplankton abundance ( P = 0.676). The traditional practice of residue burning post harvest therefore has a substantially negative effect on zooplankton biodiversity. [ABSTRACT FROM AUTHOR]

Abstract: The effects of commercial formulation containing quinclorac and metsulfuron-methyl herbicides on acetylcholinesterase (AChE), antioxidant profile and metabolic parameters in teleost fish (Leporinus obtusidens) were studied. The fish were exposed during 90 days to commercial formulation containing quinclorac (204μgL−1) and metsulfuron-methyl (5.8μgL−1) herbicides in rice field irrigated condition. AChE activity in the brain and muscle decreased after exposure to both commercial formulations. The same response was observed for the TBARS levels in brain, liver and muscle. Liver catalase activity reduced after exposure to commercial formulation containing quinclorac and metsulfuron-methyl herbicides. Metabolic parameters in the liver and white muscle (glycogen, lactate, protein and glucose) were determined. These parameters showed different changes after exposure to both commercial formulations. This study pointed out long-term effects of exposure to commercial formulations containing herbicides used in rice on metabolic and enzymatic parameters in tissues of L. obtusidens. [Copyright &y& Elsevier]

Abstract: Mosquito-borne arboviruses are a significant health issue in the irrigation areas of south-eastern Australia. Fipronil, a pyrazole insecticide with strong activity against larval Culex species, was tested for its acute effects on Simocephalus elizabethae (Daphniidae) and Polypedilum nubiferum (Chironomidae), two non-target invertebrates associated with Australian rice field mosquito habitats. Technical and formulated fipronil were assessed in the presence or absence of particulate artificial diets in 48h static bioassays. LC50 values for neonate S. elizabethae ranged from 11.13 to 19.12μgl−1 whilst those for final instar P. nubiferum ranged from 0.89 to 2.18μgl−1. Feeding during exposure significantly reduced the susceptibility of P. nubiferum to both technical and formulated fipronil. The effect of feeding was less consistent in Simocephalus bioassays, where much less food was present. We investigated whether adsorption to unconsumed food particles may have limited fipronil bioavailability by using solid-phase microextraction and gas chromatography to measure the available fipronil from fed and unfed systems 24h after establishment. Differences between the systems were not significant (P >0.05). The significantly higher LC50 values in the fed Polypedilum bioassays do not appear to be a consequence of reduced fipronil bioavailability. Observed differences in toxicity probably reflect increased stresses associated with food deprivation in the unfed bioassays. Our results support published data on the toxicity of fipronil to aquatic invertebrates which suggest that the use of this material as a mosquito larvicide may cause disruption to aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Abstract: Herbicide contamination of aquatic ecosystems is a serious global environmental concern. Several herbicides enhance the intracellular formation of reactive oxygen species, and can lead to the damage of macromolecules and to a decrease of oxidant defenses in a wide range of non-target microorganisms including cyanobacteria. The effects of molinate (a thiocarbamate herbicide used for controlling grassy weeds in rice fields) on the activities of antioxidant enzymes such as superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase, and glutathione S-transferase were evaluated in Nostoc muscorum, a freshwater cyanobacterium with a significant spread in Portuguese rice fields. These were determined in N. muscorum cultures acutely (72h) exposed to concentrations ranging from 0.75 to 2mM of molinate. This study also analyzed the effects of molinate on: (1) the nonenzymatic antioxidant contents (reduced and oxidized glutathione, carotenoids, and proline), (2) the oxidative cell damage measured in terms of lipid peroxidation (MDA level) and electrolyte leakage (intactness of plasma membrane), and (3) the total fatty acid profile. The results showed that the activities of all antioxidant enzymes decreased dramatically with the rising concentration of molinate after 72h. Time-dependent and concentration-dependent increase in MDA and enhanced cell membrane leakage were indicative of lipid peroxidation, formation of free radicals and oxidative damage. Compared to control, 72-h herbicide exposure increased lipid peroxidation by 5.4%, 19% and 28% with 0.75, 1.5 and 2mM of molinate, respectively. Similarly, herbicide stress induced an increase in electrolyte leakage (5.8%, 29.5% and 30.2% above control, with 0.75, 1.5 and 2mM of molinate, respectively). The increased production of proline at higher molinate concentrations (the values rose above control by 45%, 95% and 156% with 0.75, 1.5 and 2mM, respectively) indicated the involvement of this osmoprotectant in a free radical scavenging mechanism. Moreover, a radical decline in both glutathione pool, carotenoids and saturated fatty acids were also observed. The results of the present study lead us to conclude that: (1) both enzymatic and nonenzymatic antioxidative defense system of N. muscorum are dramatically affected by molinate, (2) the herbicide induces peroxidation, (3) it contributes to an increase of the unsaturation level of cell membrane fatty acids. These evidences should be taken in account when using N. muscorum as an environmental indicator species in studies of herbicide biotransformation and biomarker response as well as in environmental monitoring programmes. [Copyright &y& Elsevier]

Thirty weed species belonging to 14 families including one pteridophyte; two monocots and eleven dicots families were recorded from rice fields of Botanical Garden, Azakhel. Poaceae with seven species was dominant family followed by Asteraceae with 5 and Fabaceae with 3 species. The remaining families had less than three species. Life form spectra showed 19 therophytes, 6 hemicryptophytes, 4 geophytes and one chaemophyte. The leaf size spectra showed 13 nanophylls, 6 microphylls, 6 macrophylls, 3 leptophylls and 2 mesophylls species. Phenological behavior showed that 17 species were in vegetative stage, 10 were in reproductive stage and 3 were in post-reproductive stage. [ABSTRACT FROM AUTHOR]

ivity of B-esterases (BChE: butyrylcholinesterase and CbE: carboxylesterase using two model substrates: α-naphthyl acetate and 4-nitrophenyl valerate) in a native frog, Leptodactylus chaquensis from rice fields (RF1: methamidophos and RF2: cypermethrin and endosulfan sprayed by aircraft) and non-contaminated area (pristine forest) was measured. The ability of pyridine-2-aldoxime methochloride (2-PAM) to reactivate BChE levels was also explored. In addition, changes in blood cell morphology and parasite infection were determined . Mean values of plasma BChE activities were lower in samples from the two rice fields than in those from the reference site. CbE (4-nitrophenyl valerate) levels varied in the three sites studied, being highest in RF1. Frog plasma from RF1 showed positive reactivation of BChE activity after incubation with 2-PAM. Blood parameters of frogs from RF2 revealed morphological alterations (anisochromasia and immature erythrocytes frequency). Moreover, a major infection of protozoan Trypanosoma sp. in individuals from the two rice fields was detected. We suggest that integrated use of several biomarkers (BChE and CBEs, chemical reactivation of plasma with 2-PAM, and blood cell parameters) may be a promising procedure for use in biomonitoring programmes to diagnose pesticide exposure of wild populations of this frog and other native anuran species in Argentina. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the ecotoxicological effects of water coming from untreated organic and conventional rice field production areas in the Ebro Delta (Catalonia, Spain) treated with the herbicides oxadiazon, benzofenap, clomazone and bensulfuron-methyl and the fungicides carbendazim, tricyclazole and flusilazole. Irrigation and drainage channels of the study locations were also included to account for potential toxic effects of water coming in and out of the studied rice fields. Toxicity tests included four species ( Pseudokirchneriella subcapitata, Desmodesmus subcapitatus, Chlorella vulgaris and Daphnia magna), three endpoints (microalgae growth, D. magna mortality and feeding rates), and two trophic levels: primary producers (microalgae) and grazers ( D. magna). Pesticides in water were analyzed by solid phase extraction-liquid chromatography-electrospray-tandem mass spectrometry (LC-ESI-MS/MS). Negative effects on algae growth and D. magna feeding rates were detected mainly after application of herbicides and fungicides, respectively, in the conventional rice field. Results indicated that most of the observed negative effects in microalgae and D. magna were explained by the presence of herbicides and fungicides. The above mentioned analyses also denoted an inverse relationship between phytoplankton biomass measured as chlorophyll a and herbicides. In summary, this study indicates that in real field situations low to moderate levels of herbicides and fungicides have negative impacts to planktonic organisms and these effects seem to be short-lived. [ABSTRACT FROM AUTHOR]

The article presents a study that provides comprehensive and comparative analysis of the enzymatic antioxidant defense systems of Anabaena cylindrica, exposed to the herbicide bentazon, an active ingredient of basagran. It highlights the significant occurrence of the organisms on the rice fields of Portugal. Obtained results of the study suggest that the alterations of antioxidant systems of the organisms might be a useful biomarkers of bentazon exposure and explains the oxidative stress pathways of bentazon.

The article discusses a review and an experiment concerning the influence on birds of rice field management practices during the growing season. According to a review, the factors affecting the composition and abundance of bird species in a rice field include water level, rice plant structure, and use of pesticides. Water at intermediate levels (10-20 cm) was discovered to sustain high bird density and diversity, while dense, tall plants reduce prey availability. Pesticides and herbicides are known to be toxic to birds.

The article discusses a study which revealed the effects of rice agriculture on waterbird population size and dynamics. The study observed the breeding habits of herons and egrets living within the three sectors of northwestern Italy such as rice fields, planitial rivers, and small upland rivers. The population rose during the time of the study, between 1982 to 2002. Results revealed that rice fields held the bulk of the population with the rest of the breed expanding to the other sectors when population exceeded a certain level.

The article discusses a global review of the breeding habits of waterbirds in rice fields. The review intends to study the value of rice fields to breeding birds by usng breeding densities and nest success as parameters. The use of the rice lands as areas of propagation fall into several categories including nesting in standing rice crop, nesting on levees, and nesting in ditches. Birds such as ducks, shorebirds, and terns nest in rice fields while herons reside in rice fields while breeding in an adjacent habitat.

The article discusses the presence of birds in the rice fields of West Africa. West Africa's rice is cultivated along its coast, floodplains, and inland irrigated areas. All of the cultivated rice lands are considered sanctuaries for African and Palaearctic waterbirds. During the northern winter, the coastal fields contain 1.17 million wetland-related birds per hectare while the inland rice areas of Office du Niger in Mali have 730,000.

The article discusses the presence of waterbirds in the rice fields of the Mediterranean Region. Rice is considered one of the most important agricultural crops in Southern Europe. It is said to be important that the author considers rice cultivation as a factor in the conservation of some threatened birds such as the Eurasian Bittern. Agricultural practices that are considered effective in helping waterbirds survive include the avoidance of periodic flooding or dry cultivation and the maintenance of stubble during winter.

The article discusses the effect of traditional and modern methods of Chinese rice agriculture on wild birds. It states that traditional practices of rice cultivation such as planting just one crop a year and fallow flooding have a positive effect on certain bird species such as Crested Ibis. The modern technique in rice farming which uses pesticides and other types of agrochemicals are implicated to be the cause of the decline of the Black-faced Spoonbill. Further detailed studies are reportedly needed to validate such observations.

The article discusses the presence of birds in the rice fields of Korea and Japan. Rice is a major staple in Korea and Japan and 54% and 36% of their agricultural lands respectively are planted with the crop. 135 species of 430 native birds use the rice fields as foraging habitat, providing food for migratory and resident avian species. Most waterbirds prefer wide open rice fields for breeding. The population of waterbirds that consume fish or grain are said to be stable while the meat and insect eating kinds are decreasing.

Study on fish diversity and distribution in rice plots supplied with recycled and uncontrolled flow water was carried out from Season 1/2002 to Season II/2004 (August, 2002 to August, 2004) using a modified electro- shocker. A total of 13 species of fish were identified, with Cyprinidae being the dominant family in terms of the number caught (39.5%), followed by Aplocheilidae (18.2%), and Osphronemidae (12.0%). The number of species identified was lower as compared to those obtained in previous studies at selected irrigation canals in the Muda agro-ecosystem, and this due to different methodology employed. In the rice field plots irrigated by uncontrolled water flow, 13 species were recorded, whereas only 11 species were recorded in the plots irrigated by recycled water. However, based on the Shannon-Weiner Diversity and Evenness Indices, the values for the recycled water plots were higher (0.8764 and 0.84 16, respectively) compared to the values obtained for the uncontrolled flow plots (0.8131 and 0.7300, respectively). The clustering analysis showed that the similarity in term of the fish species in both plots is high at 0.8462. In particular, Esomus metallicus was the dominant "species catch" (36.4%), followed by Aplocheilus panchax (18.2%) and Anabas testudineus (10.6%). Most of the species identified were well-adapted to survive under the extreme conditions of the rice fields, such as the lower and higher D.O. and water temperature readings of 0.3-14.8 mgfL and 14.0-41.0°C, respectively. However, floods that occurred in Season 1/2004 were found to have influenced the fish diversity as some riverine species, such as Barbodes gonionotus and Cyclocheilichthys apogon, were caught in the studied rice field plots. [ABSTRACT FROM AUTHOR]

Agricultural practice is an important factor that threatens biodiversity. However, modified habitats such as irrigated rice fields could serve as potential refuges for several species of amphibians. This study describes the composition of an anuran assemblage in an irrigated rice field system in the Pantanal floodplains of central Brazil. The low species richness found in rice fields and neighbouring habitats can be interpreted as resulting from the structural limitations of a modified environment. Flooding occurs for longer periods than in natural areas and leads to a lack of dry space, hindering the presence of terrestrial anuran species. Furthermore, the absence of herbaceous vegetation and shrubs in cultivated fields prevents the establishment of species of large tree frog. A positive correlation was found between rainfall and richness, although the abundance of some species did not fit this relationship. The present study suggests that only anuran species that are generalists and highly resilient will survive as the natural wetlands are transformed into irrigated rice plantations. [ABSTRACT FROM AUTHOR]

1. During migratory stopovers, animals are under strong time stress and need to maximize intake rates. We examine how foragers react to resource depletion by studying the foraging ecology and foraging site selection of black-tailed godwits Limosa l. limosa staging in rice fields during their northward migration stopover (January–March 2007). 2. We analysed godwit abundance and foraging behaviour, sampled the availability of rice in the fields and used the functional response model to predict the giving-up density (GUD) of rice kernels when godwits should give up a rice field. Sightings of individually colour-marked birds were used to verify whether individuals moving between rice fields confirmed the predicted GUD. 3. Black-tailed godwit intake rates at different rice densities fitted Holling’s functional response curve. The predicted GUD of rice necessary to balance allometric estimates of daily energy expenditure (DEE) and measured time budgets were confirmed by GUD measured in the field. 4. Individually marked birds moved towards rice fields with higher rather than lower rice densities more often than randomly expected. These birds increased the measured intake rates after this move. 5. Godwit foraging caused a decrease in the rice density of individual fields during the stopover period. Despite this, overall intake rates remained constant as godwits reacted to resource depletion by moving to a new foraging site as soon as their intake rate falls below the required levels to achieve DEE. [ABSTRACT FROM AUTHOR]

The article focuses on a study which investigates the effects of toxicity of the herbicides bentazon and molinate on the growth of Nostoc muscorum, a cyanobacterium in Portuguese rice fields, under laboratory conditions during time- and concentration-dependent exposure for 72 hours. It reports that toxic concentrations at 0.75-2 millimeter (mM) of both herbicides have pleiotropic effects on the cyanobacterium. It says that molinate exhibits more toxicity to growth, chlorophyll-a, carotenoids, and phycobiliproteins contents. It mentions that the herbicides increased protein content and more pronounced with molinate concentrations at 1.5-2 mM. It notes that molinate increases carbohydrates content while bentazon decreases it. Inhibition of photosynthesis and respiration is also observed.

The article provides information on a study which analyzed the phenology, dynamics of the stopover and size of the Portuguese staging and western limosa population. The study described the phenology in comparison with the situation in the early 1990s and estimated staging duration of individual godwits and the total number of godwits using this staging area. The research argues that processes in Iberia are not likely to have contributed to the population decline as the area of rice cultivation has increased.

In the Ebro River basin, point and diffuse pollution of heavy metals stems mainly from industry and agriculture. Bioaccumulation patterns were examined under different pollution sources (point and diffuse) using levels of heavy metals (As, Cd, Cr, Cu, Hg, Pb and Zn) in abdominal muscle tissue of Procambarus clarkii. P. clarkii captured under point source effects presented the highest concentrations of Hg, Pb and As; and were related with distance to the source of industrial waste sediments. Mean Hg levels in crayfish exposed to point sources of metals significantly exceeded legal allowed values established by the European Union legislation. In the Ebro Delta, high levels of As, Cr, Cu and Zn were associated with traditional agriculture activity (diffuse pollution) as well. These results demonstrate the potential of P. clarkii to bioaccumulate heavy metals from both point and diffuse sources and hence potentially transfer these metals to higher trophic levels. [Copyright &y& Elsevier]

Background: Wetlands are species-rich habitats performing valuable ecosystem services such as flood protection, water quality enhancement, food chain support and carbon sequestration. Worldwide, wetlands have been drained to convert them into agricultural land or industrial and urban areas. A realistic estimate is that 50 % of the world's wetlands have been lost. [ABSTRACT FROM PUBLISHER]

The article presents a study which determines geographical origins, return rates, and movements of the near-threatened black-tailed godwits or Limosa limosa by colour marking in the Extramadura rice fields in Iberia. It explains that unknown fundamental aspects such as return rates exist on the stopover ecology of the godwits in Iberia. It discloses that captured godwits were marked and measured for movements, return rates, and geographical origin. It reveals that the black-tailed godwits staying in rice fields belong to the subspecies L.l. limosa and that Extramadura is a possible take-off site for the said subspecies.

Model-based analyses of species-habitat relationships can help to clarify which factors influence the establishment and spread of species. The coypu (Myocastor coypus) is a semi-aquatic rodent native to South America, which has been introduced worldwide, including Italy. We used logistic regression to analyse the species distribution according to habitat attributes of agro-ecosystems in Piedmont Region. The resulting model correctly predicted the presence and absence of the coypu in the initial data and also in the part of the study area used for cross-validation. Our analysis confirmed that the coypu is a typical lowland species, which particularly uses flat areas below 300 m a.s.l. The presence of coypus was strongly correlated with the presence of rice fields. During the rice-growing season, a network of canals with running water enables them to colonize this vast area. On the other hand, coypus are less likely to be present where the surface covered by woodlands and urban areas, other crops patches density, and orchards and poplar plantations patch sizes increase. A global coypu control strategy must be based primarily on preventing further introductions, and the results of this study could help to produce future risk assessments. [ABSTRACT FROM AUTHOR]

Abstract: A high proportion of threatened and near-threatened species in the world now inhabit farmland. Although much data regarding the impact of agriculture on farmland biodiversity have been accumulated in Western countries, such information, particularly on the impact of rice cultivation, is fragmentary in other parts of the world and has rarely been disseminated internationally. Therefore, this paper aims to clarify what information has become available through earlier studies in Japan, where farmland mainly consists of rice paddy areas, and give directions for future studies about the impact of agriculture on farmland birds in Japan. This study made three notable observations. First, a review of earlier studies of farmland bird species in Japan uncovered some evidence of both increases (e.g., wildfowl and cranes) and declines (e.g., waders) in population size. Second, this paper closely examined case studies of two types of typical farmland birds: (1) geese and cranes foraging on crops and/or harvested remains of crops and (2) waders and egrets foraging on small organisms in farmland, not agricultural crops. This portion of the study identified some potential routes through which human activities in farmland affect bird species in Japan, and offered practical implications for conservation and management of these species supported by scientific data. Finally, based on the results of this review, three key tasks for future conservation studies and practices in Japanese farmland were suggested: (1) establishing quantitative indices based on monitoring surveys in farmland to track the population status, (2) collecting further evidence of the impact of agriculture, particularly on population-level responses by birds, and in a food-web context, and (3) applying evidence-based conservation to practice. [Copyright &y& Elsevier]

In order to assess pollutant transfer in Camargue ponds from bordering agrosystems, a biomonitoring assay was conducted in irrigation and drainage channels of rice fields in the Rhone Delta (France). A filter-feeding bivalve, the Asian clam, Corbicula fluminea, was used as bioindicator and caged in upstream and downstream channels of an area of conventional rice fields. After 6 weeks incubation, many lipophilic biocides were identified in Corbicula tissues, including pesticides used in rice plantations (pretilachlor, oxadiazon), pesticides presumed in use in the Rhone basin [diuron and its metabolite 3,4 dichloroaniline (3,4-DCA)] and organochlorine pesticides (OCPs) banned for several decades. In addition, PCBs were highly bioaccumulated in Corbicula. Downstream bivalves had significantly lower concentrations of OCPs, PCB and 3,4-DCA. However, the exposure biomarkers (glutathione S-transferase, catalase and propionylcholinesterase) were not correlated with the decreased concentrations. The results of this experiment raise several questions concerning the potential role of immersed plants in a retention process. [Copyright &y& Elsevier]