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111.
Fasheng Zou Hanhua Zhang Tom Dahmer Qiongfang Yang Junxin Cai Wei Zhang Chaoyu Liang 《Forest Ecology and Management》2008,255(11):3813-3818
Twenty-two species shorebirds were recorded on mangrove wetlands surrounding Leizhou Peninsula, Guangdong Province, China. One recorded species, Spoon-billed Sandpiper (Eurynorhynchus pygmeus), is listed as endangered in the IUCN Red List (World Conservation Union) and this was the first record of the species at Leizhou in this study. Most recorded species are listed in the Sino-Japan or Sino-Australia Agreement on Conservation of Migratory Birds. Dunlin (Calidris alpina), Kentish Plover (Charadrius alexandrinus), and Greater Sand Plover (Charadrius leschenaultii) were dominant, accounting for 34%, 32%, and 12% of total individuals, respectively. Five survey sites were designated by habitat type. There was no significant difference in species, but total abundance differed significantly among survey sites. More species were recorded in winter and spring than in summer. One hundred and sixty-five species of benthos were recorded. Total mean biomass and density of benthos was 223.3 ± 74.8 g/m2 (±S.E.), density 210.97 ± 67.6 ind./m2, respectively. Mollusks accounted for 83.4% of total biomass, and 75.6% of total density. Both biomass and density of benthos varied significantly among survey sites. There was no significant difference between spring and autumn on biomass or density of benthos. There was a significant and negative correlation between number of shorebirds and densities of polychaetes on mudflats. Shorebird species richness (F1,3 = 13.14, p = 0.036) and abundance (F1,3 = 12.59, p = 0.037) were significantly and positively correlated with mudflat area. Stopping losses of mangrove habitat and tidal flats is the top priority measure for shorebird conservation. Reducing the impacts of human disturbance on both habitats and birds is an urgent necessity for mangrove wetland conservation management. 相似文献
112.
R. M. Nair M. Götz S. Winter R. R. Giri V. N. Boddepalli A. Sirari T. S. Bains G. K. Taggar H. K. Dikshit M. Aski M. Boopathi D. Swain A. Rathore V. Anil Kumar E. C. Lii L. Kenyon 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(2):349-364
The segmentation of symptoms during image analysis of diseased plant leaves is an essential process for detection and classification of diseases. However, there are challenges involved in the task, many of them related to the variability of image and host/symptom characteristics and conditions. As a result of those challenges, the methods proposed in the literature so far focus on a specific problem and are usually bounded by tight constraints regarding image capture conditions. This research explores a new automatic method for segmenting disease symptoms on plant leaves that was designed to be applicable in a wide range of situations. The proposed technique employs only color channel manipulations and Boolean operations applied on binary masks, thus being simpler and more robust compared to many previously described automatic methods. Its effectiveness is demonstrated by tests performed over a large database containing images of 77 different diseases of 11 plant species. A comparison with manual segmentation is also presented, further reinforcing the advantages of the proposed approach. 相似文献
113.
The underlying principles and traditional knowledge concerning indigenous agroforestry systems (AFS) around the world have been used successfully in the design of improved systems; but lately there has been a slow-down in that effort. Recognizing that Cinderella, by analogy, refers to an individual whose attributes were unrecognized or one who unexpectedly achieved success after a period of obscurity and neglect, we propose Cinderella agroforestry systems for such underexploited and “forgotten” AFS. In order to highlight their unrecognized potentials, a few such systems that are location-specific and little-known outside their areas of existence were selected from around the world. Each selected system is unique in terms of its production, environmental, and sociocultural attributes; but none had been described in quantitative terms of ecology and production. A qualitative SWOT (strengths–weaknesses–opportunities–threats) analysis of the systems showed several commonalities among them. While sustainability, multi-functionality, and high sociocultural values are common strengths, low levels of production and lack of research- and technology inputs to improve the system are the major weaknesses. The opportunities emanating from strengths and weaknesses are also common to all the systems; and “threats” to these systems arise mostly from ramifications of government policies. Given the acknowledged role of AFS in climate-smart agriculture and the current global momentum for working with communities to better manage landscapes, learning from success stories of the Cinderella AFS could suggest models for sustainable development, and efforts in that direction should also be incorporated into global agroforestry research agendas. 相似文献
114.
P. V. Nidheesh Praveen Thomas Kishore A. Nair Jones Joju P. Aswathy R. Jinisha George K. Varghese R. Gandhimathi 《Water, air, and soil pollution》2017,228(1):51
In the present study, the ability of Hibiscus rosa-sinensis leaf extract (HLE) to act as a natural coagulant for the water treatment was tested. Synthetic turbid solutions were prepared using kaolinite, and the efficiency of HLE was examined for low and high turbid solutions. HLE was very effective in high turbid solutions than in low turbid water and follows enmeshment mechanism of destabilization. An insignificant effect of alkalinity on the performance of HLE was observed. The addition of NaCl increased the dissolution of coagulation active species and enhanced the efficiency of HLE, significantly. Hydroxyl and carboxyl groups present in HLE were the major functional groups responsible for the bonding between coagulant and kaolinite. The efficiency of alum was very high compared to that of HLE in both turbid solutions. But the optimal dosages of HLE were lesser than that of alum. Thus, HLE can be used as a coagulant aid for the effective treatment of water. 相似文献
115.
Chithra Syamala Susan John Kuzhivilayil M. Manikantan Nair J. Sreekumar 《Communications in Soil Science and Plant Analysis》2017,48(6):595-607
In India, cassava cultivation is confined in South India. In Tamil Nadu, tubers are used as raw material for starch and sago industry. About 8–10 large-scale starch factories and 150–200 small-scale starch and sago production units are generating nearly 40–60 tonnes of solid waste (thippi) per annum creating serious environmental pollution. A study undertaken to manage it through composting to a nutrient-rich organic manure revealed thippi as acidic with low major and micronutrient concentration, high water-holding capacity, good porosity, low bulk density, high starch, fiber, low protein, and cyanide. Composting of thippi with different combinations of raw materials, microbial cultures, and earthworms indicated that thippi enriched with gliricida and cassava leaves and composted with earthworm had the highest nutrient concentration with narrow carbon to nitrogen (C:N) ratio. The mean concentrations of N, phosphorus (P), potassium (K) calcium (Ca) and magnesium (Mg), iron (Fe), manganese (Mn), copper (Cu), and zinc (Zn) in thippi compost were 1.32, 3.82, 0.40, 2.18, 0.96, 1.11, 0.08%, 11.23, and 89.93 mg/kg, respectively, which is 3.5, 49,7, 32.5, 8, 185, 100, 2.5, and 12 times than thippi. Thippi compost had low bulk density, starch, without fiber and cyanide but high protein suggesting this protocol as a possible alternative for the management of thippi. 相似文献
116.
Z. Abraham R. Senthilkumar K. Joseph John T. V. R. S. Sharma N. V. Nair M. Unnikrishnan P. M. Kumaran Johnson K. George S. Uma M. Latha S. S. Malik S. K. Mishra D. C. Bhandari S. K. Pareek 《Genetic Resources and Crop Evolution》2008,55(8):1279-1289
The Andaman and Nicobar (A&N) group of islands is immensely rich in plant biodiversity. Andaman’s native tribes are hunter-gatherers,
sustaining on wild or marine food and practically do not have any cultivation. Diversity in cultivated crops is presently
maintained in home gardens by settlers from the mainland and other adjoining countries. The National Bureau of Plant Genetic
Resources (NBPGR) through explorations either alone or in association with CARI or with other ICAR institutes has collected
1234 accessions in 48 exploration and collection missions. Variability was collected in rice, cowpea, black gram, green gram,
okra, Chinese spinach, ash gourd, taro, cucumber, pumpkin, bottle gourd, ridge gourd, bitter gourd, chilli, greater yam and
coconut. Indigenous landraces are absent. The in situ conservation of the wild relatives of crops is well taken care of by a large number of protected forest reserves. 相似文献
117.
Nitrogen release patterns from seven leguminous trees were determined from 8-week laboratory incubations. The quantities
of extractable NH4
+-N and NO3
– released to the soil to which the leaves had been applied was determined at weekly intervals and was related to the initial
N, polyphenol, and lignin concentration of the leaves. Cumulative N mineralized was not correlated to initial N, soluble polyphenol
and insoluble tannin concentrations, but was correlated to lignin and neutral detergent fibre N (NDF-N) concentrations. The
ratios of NDF-N : N (r=0.68 at P<0.05), soluble polyphenol : N (r=0.70 at P<0.05) and (lignin+polyphenol) : N (r=0.75 at P<0.05) were negatively correlated with N release. Total polyphenol content was not a useful predictor of N release, but the
reactivity of the polyphenols as measured by their protein-binding capacity can be a useful predictor. In addition to measuring
the concentration of polyphenols, their reactivity with proteins must be measured, in order to assess their role in regulating
N release. The (lignin+polyphenol) : N ratio could be used to screen leguminous tree leaves for their potential to release
N in short-term experiments. This would allow for rapid screening of a large number of trees without detailed and expensive
field experimentation.
Received: 30 June 1997 相似文献
118.
119.
N.V. Nair 《Euphytica》1999,108(3):187-191
Four intergeneric hybrids were produced by crossing sorghum [ Sorghum bicolor (L.) Moench, 2n =20] as a female parent with sugarcane ( Saccharum officinarum L., 2n = 112). The hybrids were morphologically similar to the sugarcane parent, but lacked vegetative vigour. Sorghum characters
present in the hybrids included soft texture of the leaves, tight clasping of the leaf sheaths, presence of aerial roots and
triangular ligule. All the hybrids were highly susceptible to natural incidence of mites. Somatic chromosome number of the
hybrids ranged from 2n = 62–66, indicating n+n transmission. This is the first report of Sorghum × Saccharum hybrids with sorghum cytoplasm.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
120.
Yingbo Chen Huiqiang Liu Xiaoyu Hu Bowen Cheng Dongqing Liu Yufeng Zhang Sankar Nair 《Fibers and Polymers》2017,18(7):1250-1254
Membranes with high water permeation capability as well as high rejection to dye molecules are very important for dye separation. In this study, a metal organic framework structure (Cu-BTC) was fabricated in situ on a poly(vinyl difluoride) hollow fiber support for nanofiltration of dye solution. In order to protect the Cu-BTC layer, the surface was coated by crosslinking polyvinyl alcohol. The composite membranes showed no rejection to divalent salts and high rejection to Congo Red dye. It was noticed that several Cu-BTC layers could enhance dye rejection of the composite membranes. This novel composite membrane showed promising applications in the separation of dye molecules from aqueous solutions containing dissolved salts. 相似文献