Purification of Pisciculture Waters through Cultivation and Harvesting of Aquatic Biomass

1987 ◽  
Vol 19 (10) ◽  
pp. 113-121 ◽  
Author(s):  
C. Simeon ◽  
M. Silhol
Keyword(s):  
Aquatic Macrophyte ◽  
Dry Weight ◽  
Final Decision ◽  
Effluent Water ◽  
Aquatic Biomass ◽  
Growing Period ◽  
European Climate ◽  
Nuclear Plants ◽  
Economical Optimization ◽  
Water Hyacinths

The study of thermal wastes from the nuclear plants around Pierrelatte for agricultural, piscicultural, energy and environmental protection purposes resulted in the establishment of a pilot facility as early as 1976. An aquatic macrophyte pilot facility has been operational since 1983 to study the use of water hyacinths from the aspects of energy and ecology. The results obtained suggest that production yields for the 7 month growing period should exceed 60 metric tons (MT) (dry weight) per hectare in a European climate, and that such crops can feasibly be cultivated in temperate regions. The pilot facility is supplied with pisciculture effluent water, making it possible to quantify the stabilization power of the plants. Without primary decantation, with a retention time of 4 days and stabilization with water hyacinths only, the organic matter waste pond surface area required is 3.5 m2/m2 of pisciculture pond. Any primary or secondary facilities will lead to a reduction of these areas. The final decision will depend on the economical optimization of all the wastewater.

scholarly journals Vegetative and Reproductive Response to Fruit Load in Two Jojoba (Simmondsia chinensis) Cultivars

Agronomy ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 889
Author(s):  
Aviad Perry ◽  
Noemi Tel-Zur ◽  
Arnon Dag
Keyword(s):  
Vegetative Growth ◽  
Accumulation Rate ◽  
Dry Weight ◽  
High Yield ◽  
Lower Amount ◽  
Simmondsia Chinensis ◽  
Alternate Bearing ◽  
Fruit Removal ◽  
Growing Period ◽  
Fruit Load

Jojoba (Simmondsia chinensis) is a wax crop cultivated mainly in arid and semi-arid regions. This crop has been described as an alternate-bearing plant, meaning that it has a high-yield year (“on-year”) followed by a low-yield year (“off-year”). We investigated the effect of fruit load on jojoba’s vegetative and reproductive development. For two consecutive years, we experimented with two high-yielding cultivars—Benzioni and Hazerim—which had opposite fruit loads, i.e., one was under an on-year load, while the other was under an off-year load simultaneously. We found that removing the developing fruit from the shoot during an off-year promotes further vegetative growth in the same year, whereas in an on-year, this action has no effect. Moreover, after fruit removal in an on-year, there was a delay in vegetative growth renewal in the consecutive year, suggesting that the beginning of the growing period is dependent on the previous year’s yield load. We found that seed development in the 2018 season started a month earlier than in the 2017 season in both cultivars, regardless of fruit load. This early development was associated with higher wax content in the seeds. Hence, the wax accumulation rate, as a percentage of dry weight, was affected by year and not by fruit load. However, on-year seeds stopped growing earlier than off-year seeds, resulting in smaller seeds and an overall lower amount of wax per seed.

Nutrient removal by water lettuce (Pisitia stratiotes)

1996 ◽  
Vol 34 (7-8) ◽  
pp. 407-412 ◽  
Author(s):  
T. Aoi ◽  
T. Hayashi
Keyword(s):  
Growth Rate ◽  
Batch Culture ◽  
Culture System ◽  
Eichhornia Crassipes ◽  
Aquatic Macrophyte ◽  
Water Bodies ◽  
Water Lettuce ◽  
Wet Weight ◽  
Water Hyacinths ◽  
Nitrogen Phosphorus

The nutrient uptake and growth rates of the water lettuce [Pisitia stratiotes] were investigated in a batch culture system and a continuous flow system. As the water hyacinth [Eichhornia crassipes] is well known and widely researched as an aquatic macrophyte, water hyacinths were used as a control in a batch culture system. It was found that the specific growth rate of water lettuce was slightly higher in dry season, and in rainy season the growth rate of water hyacinths decreased almost 70%, but the rate of water lettuce decreased only 45%. From this result, water lettuce is thought to be grow up enough even under low solar radiation. The nitrogen, phosphorus and ash contents of biomass were about 1.5 times higher in water hyacinths than in water lettuce (N:2.15% & 1.65%, P:1.67% & 1.03%, ash 19.6% & 19.9% respectively). As the biomass of water lettuce is not so big and heavy (wet weight of water lettuce was under 100g and the width and height of the plant was under 20cm), removal of surplus biomass from water bodies is easy. It was made clear that water lettuce is very effective for removing nutrient from water bodies.

Growth dynamics in Sphaerium rhomboideum (Bivalvia: Pisidiidae)

1983 ◽  
Vol 61 (4) ◽  
pp. 868-873 ◽  
Author(s):  
G. L. Mackie ◽  
L. A. Flippance
Keyword(s):  
Reproductive Strategy ◽  
Growth Dynamics ◽  
Calcium Content ◽  
Dry Weight ◽  
Allometric Relationship ◽  
Dormant Period ◽  
Growing Period ◽  
Total Dry Weight ◽  
Curvilinear Relationships

Analyses of growth in shell dimensions and weight of Sphaerium rhomboideum from two permanent ponds showed that width has a positive allometric relationship with length and height of the shell. This results in an increase in interior shell volume that is significantly correlated with the increase in space required by developing larvae. The ovoviviparous habit of S. rhomboideum also explains most of the curvilinear relationships between clam length and total dry weight and between clam calcium content and length and weight of adults. An iteroparous reproductive strategy is shown to be dependent upon both a positive allometric relationship between larval and parent shell lengths and birth of the cohort during or immediately before an active growing period. If birth of the cohort occurs immediately before a dormant period, semelparity will occur no matter what type of allometric relationship is obtained between larval and adult shell lengths.

Yield Potential and Stratified Growth Analysis of an Indeterminate Climbing Pole Bean (Phaseolus Vulgaris) in Mexico

1982 ◽  
Vol 18 (2) ◽  
pp. 167-175 ◽  
Author(s):  
L. Fanjul ◽  
J. Kohashi-Shibata ◽  
E. Hernandez-Xolocotzi
Keyword(s):  
Growth Analysis ◽  
Dry Weight ◽  
Yield Potential ◽  
High Yield ◽  
Potential Yield ◽  
Growing Period ◽  
Bean Cultivar ◽  
Type Iv ◽  
Main Components ◽  
Major Factors

SUMMARYThe yield potential of a highly productive non-commercial Type IV bean cultivar was determined under optimum field conditions, grown in monoculture at 1 plant/m2 on trellises 3 m high. Canopy growth was analysed by dividing the stand into 25 cm horizontal strata. The main components of yield were number of inflorescences and number of pods per stratum. Daily yield for the growing period was 4.9 g dry weight/m2. Although a high yield per plant was recorded (823 g/plant) drop of young pods and seed abortion were the major factors reducing the potential yield.

scholarly journals Use of Belowground Growing Degree Days to Predict Rooting of Dormant Hardwood Cuttings of Populus

2004 ◽  
Vol 53 (1-6) ◽  
pp. 154-160 ◽  
Author(s):  
R. S. Zalesny ◽  
E. O. Bauer ◽  
D. E. Riemenschneider
Keyword(s):  
Populus Deltoides ◽  
Dry Weight ◽  
Growing Degree Days ◽  
Base Temperature ◽  
Degree Days ◽  
Planting Dates ◽  
Growing Period ◽  
Period 2 ◽  
Soil Temperatures ◽  
Total Dry Weight

Abstract Planting Populus cuttings based on calendar days neglects soil temperature extremes and does not promote rooting based on specific genotypes. Our objectives were to: 1) test the biological efficacy of a thermal index based on belowground growing degree days (GDD) across the growing period, 2) test for interactions between belowground GDD and clones, and 3) identify beneficial planting windows based on combinations of genotypes and belowground GDD. We tested two clones of Populus deltoides Bartr. ex Marsh (D133, D134) and four hybrid clones of P. deltoides × P. maximowiczii A. Henry (DM101, DM105, NC14105, NC14107). Cuttings, 20 cm long, were planted in randomized complete blocks at 15- × 15-cm spacing across three planting dates during 1999 at Alexandria, Minnesota, USA (45.9°N, 95.4°W) and Fertile, Minnesota, USA (47.3°N, 96.2°W). Temperatures at 20 cm belowground were converted to GDD with a base temperature of 10°C. We measured root, top, and total dry weight, along with number of roots after 14 d of growth. Relatively warmer and cooler soil temperatures promoted rooting for the cottonwoods and hybrids, respectively. We recommend planting after reaching a threshold of 163 belowground GDD for P. deltoides clones and planting before reaching a threshold of 173 belowground GDD for P. deltoides × P. maximowiczii clones.

scholarly journals BIOLOGICAL MANAGEMENT OF Pratylenchus brachyurus IN SOYBEAN CROPS

2019 ◽  
Vol 32 (1) ◽  
pp. 41-51
Author(s):  
Kethelin Cristine Laurindo de Oliveira ◽  
Dejânia vieira de Araújo ◽  
Angélica Carmos de Meneses ◽  
Jéssica Moreira e Silva ◽  
Rodolfo Luis Cardoso Tavares
Keyword(s):  
Grain Yield ◽  
Block Design ◽  
Dry Weight ◽  
Mato Grosso ◽  
Biological Products ◽  
Growing Period ◽  
Purpureocillium Lilacinum ◽  
Shoot Dry Weight ◽  
Microbiological Characteristics ◽  
Pratylenchus Brachyurus

ABSTRACT The efficiency of biological products combined with biological fertilization for controlling Pratylenchus brachyurus in soybean crops, and effects of these treatments on soybean crops were evaluate. A greenhouse experiment was conducted at the Mato Grosso State University, in Brazil, using a randomized block design with a 10×2 factorial arrangement, and four replications. The treatments consisted of Trichoderma asperellum, B. subtilis, Purpureocillium lilacinum, B. subtilis + T. asperellum, B. subtilis + P. lilacinum, T. asperellum + P. lilacinum, B. subtilis + T. asperellum + P. lilacinum and abamectin, and Controls with, and without nematodes. Nematode population, plant height, stem base diameter, and soil microbiological characteristics (at 60 and 120 days after sowing - DAS), shoot dry weight (60 DAS), and number of pods per plant, and grain yield (120 DAS) were evaluated. The treatments were efficient for the control of phytonematodes at 60 DAS; the efficiency of treatments with biological products increased when combined with biological fertilization. The biological products were more efficient for controlling the nematodes than abamectin at 120 DAS; and the percentage of control were higher when they were combined with biological fertilization, in both growing periods. The biological treatments resulted in better agronomic characteristics, and higher number of pods per plant, and grain yield, affecting the plants in the first growing period, and significant interaction with the biological fertilizer for these variables in the second growing period. The interaction between treatments and biological fertilization was significant for soil microbiological characteristics in the second growing period.

Aquatic macrophytes as a habitat for free-living nematodes

Nematology ◽  
2006 ◽  
Vol 8 (5) ◽  
pp. 691-701 ◽  
Author(s):  
Jasna Vidaković ◽  
Irella Bogut
Keyword(s):  
Aquatic Macrophyte ◽  
Dry Weight ◽  
Nematode Species ◽  
Trophic Group ◽  
Ceratophyllum Demersum ◽  
The North ◽  
Macrophyte Species ◽  
North Bank ◽  
Nature Park ◽  
Relative Abundances

Abstract The composition, trophic structure and diversity of nematode assemblages associated with three aquatic macrophyte species (Polygonum amphibium, Carex sp., Ceratophyllum demersum) were surveyed. Sampled stands were present at the three sites of the north bank in the Čonakut Channel (Nature Park Kopački rit, Croatia). They were all submerged during the period of investigation, which included two vegetation seasons. Nematode abundances (expressed as a number of individuals per 100 g of macrophyte dry weight) differ between the two vegetation seasons and between the sites, but not between the macrophyte species. In total, 19 nematode species were recorded. Chromadorina viridis, C. bioculata, Brevitobrilus stefanskii, Eutobrilus notus, Prodorylaimus longicaudatus and Ethmolaimus sp. were associated with all macrophyte species. Genera Eutobrilus, Brevitobrilus and Chromadorina were present at the highest relative abundances. Species diversity (H and Simpson's D) and evenness (Pielou's J), calculated on the nematode species level, display little or no change in relation to different macrophyte species. Ceratophyllum demersum associated nematode fauna had distinct dominance of one species (Eutobrilus notus) and consequently lower evenness, which was not statistically significant. Chewers (CH) represented the dominant trophic group of total nematode abundance for all three macrophyte species followed by epistrate feeders (EF). Detritus feeders (DF) and suction feeders (SF) were represented by low relative abundances. This paper is a contribution to ecology of aquatic nematodes associated with macrophyte species in mesoeutrophic to eutrophic slow flowing channel.

Selective Weed Control in Syrian Marjoram (Origanum syriacum) with Oxadiazon and Oxyfluorfen Herbicides

2006 ◽  
Vol 20 (3) ◽  
pp. 670-676 ◽  
Author(s):  
Jamal R. Qasem ◽  
Chester L. Foy
Keyword(s):  
Weed Control ◽  
Field Experiments ◽  
Dry Weight ◽  
Weed Competition ◽  
Jordan Valley ◽  
Crop Failure ◽  
Growing Period ◽  
Shoot Dry Weight ◽  
Central Jordan ◽  
Low Rate

Field experiments were conducted to study the effects of oxadiazon and oxyfluorfen on weeds and Syrian marjoram (Origanum syriacumL.) in the central Jordan Valley during the period from 1998 to 2001. Results showed that weed competition with marjoram for the whole growing period resulted in almost complete crop failure. Oxyfluorfen and oxadiazon applied preplanting or postplanting to marjoram controlled weeds effectively, resulted in significant increase in marjoram shoot fresh and dry weight yields and in more branches per plant compared with the weed-infested control. High marjoram yield was obtained with oxyfluorfen applied at 0.72 kg ai/ha in preplanting treatment and with oxadiazon at 1.25 and 0.75 kg ai/ha in pre- and postplanting treatments, respectively. In preplanting treatment, 0.36 kg ai/ha of oxyfluorfen was highly selective, but 1.44 kg ai/ha reduced marjoram yield. Conflicting results were obtained with oxadiazon under the same treatments. In postplanting, oxyfluorfen at 0.24 and 0.96 kg ai/ha significantly increased marjoram yield over the weed-infested control. However, the highest shoot dry weight of marjoram was obtained at 0.96 kg ai/ha of this herbicide. In contrast, the low rate (0.38 kg ai/ha) of oxadiazon was highly selective and increased marjoram yield, but the herbicide failed to increase yield beyond the weed-infested control when the higher rate (1.5 kg ai/ha) was used. Results showed that both oxyfluorfen and oxadiazon herbicides were highly selective and effective for weed control in Syrian marjoram, providing normal rates of both are used, although high rates of the two herbicides were also selective and increased marjoram yield over the weed-infested control.

scholarly journals Assessment of an Impact of Mechanical Regulation on Selected Morphometric and Productive Parameters of Invasive Species Solidago Canadensis Population in Agricultural Land

2015 ◽  
Vol 61 (4) ◽  
pp. 121-128
Author(s):  
Lýdia Končeková ◽  
Eva Zahradníková ◽  
Eduard Pintér ◽  
Daniela Halmová
Keyword(s):  
Agricultural Land ◽  
Dry Weight ◽  
Effective Control ◽  
Solidago Canadensis ◽  
Growing Period ◽  
Anthropogenic Habitat ◽  
The Difference ◽  
The Impact ◽  
Number Of Individuals ◽  
Mechanical Regulation

Abstract Repeated mowing is considered as one of the effective control methods against species of the genus Solidago. This paper evaluates the impact of the repeated mowing on selected morphometric and productive characteristics of the invasive neophyte Solidago canadensis in the district of Rimavská Sobota in Central Slovakia. Permanent research plots (PRPs) were established within anthropogenic habitat on an abandoned land that was divided into two variants. In the first variant, the mechanical regulation - mowing was applied. The second variant was without the regulation. The mechanical regulation of the populations was carried out in June and August during the growing season 2011. The results showed that the mechanical regulation did not have a clear impact on the population density. The decreasing trend of the number of shoots within the mowed variant was found only in one research plot (PRP3). The other plots showed an increase in the number of individuals by 2.7 and 32.7% between the mowings. Statistically highly significant differences in terms of the mowing impact on the height of the individuals were found in all PRPs. The difference in the weight of dry aboveground biomass between the mowings was 221.87 g, which represents 36.41%. Double the difference (48.8%) was recorded in the dry weight of the underground biomass in the regulated stand compared with the unregulated stand (165.1 and 322.5 g/m2, respectively). Although there was a short-term success achieved by the application of the two mowings during the growing period, the pursued objective was not reached.

scholarly journals Effect of Silicate Fertilizer on the Growth and Yield of Two Local Indonesian Varieties of Rice (Oryza sativa L.)

2021 ◽  
Author(s):  
D.W. Widjajanto ◽  
Sumarsono . ◽  
Endang Dwi Purbajanti
Keyword(s):  
Oryza Sativa ◽  
Oryza Sativa L ◽  
Dry Weight ◽  
Growth And Yield ◽  
Rice Varieties ◽  
Growing Period ◽  
Randomized Design ◽  
Significant Difference ◽  
Completely Randomized Design ◽  
Beneficial Elements

Background: The beneficial elements availability such as silicon was determined rice growth and yield. Rice requires a different dose of silicon during the growing period. Experiment was aimed to investigate the effect of silicate levels, rice varieties and the interaction of the two on the growth and yields of two local Indonesian varieties of rice. Methods: A completely randomized design of factorial pattern with 4 replications was used in the experiment. Treatments consisted of No added SiO2 (Si-0); added 100 and 200 kg SiO2 ha-1, respectively for Si-100 and Si-200 and two local rice varieties, Pandan wangi (P1) and Mentik susu (P2). Result: The treatment had no significant effect on growth and yield of rice. Addition of 100 and 200 kg SiO2 ha-1 to P1 and P2 did not show a significant difference on the growth and yield of rice compared to control (P0). Plant height and root dry weight at P1 was lower than P2, but the 1,000-grain weight was showed, vice versa. Silicon addition up to 200 kg SiO2 ha-1 may not be recommended to be applied in rice cultivation, especially Pandan wangi and Mentik susu varieties. Improving the two varieties, further research is needed by increasing the silicon doses. 

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