Analysis of hydrobiological responses to anthropogenic and natural influences in a lagoon system in the Gulf of California

2016 ◽  
Vol 45 (1) ◽  
Author(s):  
José Alfredo Arreola-Lizárraga ◽  
Gustavo Padilla-Arredondo ◽  
Julio Medina-Galván ◽  
Lía Méndez-Rodríguez ◽  
Renato Mendoza-Salgado ◽  
...  
Keyword(s):  
Gulf Of California ◽  
Trophic Status ◽  
Coastal Upwelling ◽  
Coastal Lagoons ◽  
Semiarid Region ◽  
Nutrient Inputs ◽  
Nutrient Input ◽  
Lagoon System ◽  
One Year ◽  
Nitrite Nitrate

AbstractThe hydrological characteristics and the rate of organic matter supply from coastal lagoons help to understand their responses to nutrient input by anthropogenic and natural sources. The aim of this study was to determine the hydrologic and trophic status of the El Rancho-Empalme lagoon system in a semiarid region in the Gulf of California, Mexico. This lagoon system consists of two geomorphological subsystems which are affected by nutrient inputs from shrimp farm effluents and coastal upwelling. Sampling was conducted over the course of one year and included measurements of temperature, salinity, and dissolved oxygen, surface water grab samples to analyze nitrite, nitrate, ammonia, orthophosphate, and chlorophyll

Nutrient Input and Trophic Status of the “Neue Donau”, a High-Water Control System along the River Danube in Vienna, Austria

1990 ◽  
Vol 22 (5) ◽  
pp. 137-144 ◽  
Author(s):  
M. T. Dokulil ◽  
G. A. Janauer
Keyword(s):  
Water Quality ◽  
Control System ◽  
Trophic Status ◽  
High Water ◽  
Nutrient Concentrations ◽  
Nutrient Input ◽  
Water Control ◽  
Trophic Conditions ◽  
River Danube ◽  
High Nutrient

The system “Neue Donau” functions as a control system for high waters of the river Danube and is an important recreational area for many people. Water quality and trophic status of the water body is thereforeof prime importance. The high nutrient concentrations of the river Danube (P-tot 238±41µg/l, N-tot 2.53±0.78 mg/l) reach the system via groundwater seepage. Present conditions in the basin of Neue Donau are,as a result of this nutrient in-flux,eutrophic to hypertrophic. Average values during the summer period have declined from 366 µg/l total phosphorus to 78 µg/l, and from 86 µg/l chlorophyll-a tol7µg/l between the years 1985 and 1988. However, a dam which is planned in the river at Vienna will permanently raise the water level of the river thus increasing the the groundwater flow in the direction to the Neue Donau and therefore the nutrient input which will enhance trophic conditions in the impoundment. Since macrophytes play an important role in one part of the system macrophyte management together with measures along the river are some of the suggested strategies to keep the system Neue Donau at acceptable trophic conditions and good water quality.

scholarly journals Nutrient Uptake and Agronomic Efficiencies of Leaf Litter Compost as Nitrogen Source in Vegetable Cowpea (Vigna unguiculata subsp. unguiculata)

2021 ◽  
Author(s):  
Reshma Das ◽  
Sheeba Rebecca Isaac
Keyword(s):  
Nutrient Uptake ◽  
Leaf Litter ◽  
Vigna Unguiculata ◽  
Crop Residues ◽  
Block Design ◽  
Poultry Manure ◽  
Nitrogen Sources ◽  
Nutrient Inputs ◽  
Nutrient Input ◽  
Nutrient Contents

Background: Nutritional security overrides food security and the present day agriculture focusses more on sustainable and regenerative agriculture in which use of organic inputs assumes prime significance. The search for viable alternatives to the chemical sources of nutrients demands production of the organic nutrient inputs in large quantities. Organic nutrition is expensive on account of the low nutrient contents and large quantum needed and hence unless produced in situ, turn out to be highly expensive. Organic wastes in the form of crop residues are available in plenty in agricultural fields. Tree leaf litter is another biowaste considered as menace under off farm situations. Rapid resource recycling techniques offer immense potential for the safe disposal of the litter and conversion to quality manures. In this background an experiment was conducted to assess the efficacy of litter composts as nitrogen sources in vegetable cow pea (Vigna unguiculata subsp. unguiculata) in terms of the agronomic efficiencies and nutrient uptake. Methods: The field experiment was conducted in College of Agriculture, Vellayani, Thiruvananthapuram, Kerala Agricultural University during December 2018 to March 2019 in randomized block design with three replications. The treatments included the compost of the two tree species litter prepared by composting with different decomposer organisms and additives and enriched with the biofertilizer, PGPR Mix I. Result: The results of the experiment revealed the highest vegetable yields (7.80 t ha-1) in the treatment involving mango leaf litter composted with glyricidia leaves and earthworms on par with Kerala Agricultural University package of practices recommendation for cowpea and it was 2.7 times that in absolute control. The total nutrient uptake was the highest with mango litter co-composted with poultry manure as nutrient input. Agronomy efficiency indices, in terms of nitrogen were significantly superior for the treatments including mango litter composts and hence prove a suitable nutrient input in vegetable cowpea cultivation.

Distribution patterns of the warrior swimming crab, Callinectes bellicosus, fishery in Bahía Magdalena, Baja California Sur, Mexico

Crustaceana ◽  
2019 ◽  
Vol 92 (11-12) ◽  
pp. 1279-1293 ◽  
Author(s):  
Juan C. Castro-Salgado ◽  
Mauricio Ramírez-Rodríguez ◽  
Gustavo-De la Cruz-Agüero ◽  
Verónica Castañeda-Fernández-de-Lara
Keyword(s):  
Gulf Of California ◽  
Coastal Lagoons ◽  
Warm Season ◽  
Distribution Patterns ◽  
Cold Season ◽  
Swimming Crab ◽  
Mexican Pacific ◽  
Temporal Behaviour ◽  
Average Size ◽  
Bahia Magdalena

Abstract Spatial and temporal distribution patterns of the warrior swimming crab Callinectes bellicosus fishery in the Mexican Pacific were investigated. Geo-referenced commercial trap capture data derived from 44 trips in the Bahia Magdalena were analysed. Three fishing zones (Z1, inner; Z2, middle; Z3, mouth of the bay) and two climate seasons (warm, July-December; and cold, January-June) were defined previously. There were 1099 traps in Z1, 715 in Z2 and 2111 in Z3; in the warm season, 2091 traps were checked, whereas 1834 were checked in the cold season. The average number of individuals per trap (CPUE) varied by sex, zone and season, however, male crabs always predominated. During the warm season, large males (CW > 115 mm) exhibited the greatest value of CPUE. On average, the males represented 77% during the warm season and 84% during the cold season. The average size of the males (125 ± 0.843 mm CW) was significantly higher than the average size of females (121 ± 1.140 mm CW). The catch was composed of large mature males but females were absent in Z1; in comparison, both large mature males and females, in addition to ovigerous females, composed the catch at the mouth of the bay (Z3). Crab abundance was notably reduced in the cold season, especially for female crabs. The temporal behaviour of the warrior swimming crab in Bahia Magdalena is similar to that reported from the coastal lagoons of the Gulf of California; however, the low presence of females throughout the year could be related to their preferred environmental conditions, which include deeper areas with more current circulation, like those that occur at the mouth of the bay. These data corroborate the necessity to interpret with caution the crab population dynamics solely based on results derived from fishing with traps in coastal lagoons.

Analysis of crab size structure and the fishing effort applied to a crab fishery in northwest Mexico

Crustaceana ◽  
2018 ◽  
Vol 91 (2) ◽  
pp. 225-237 ◽  
Author(s):  
César A. Heredia-Delgadillo ◽  
Guillermo Rodríguez-Domínguez ◽  
Raúl Pérez-González ◽  
Nicolás Castañeda-Lomas ◽  
Sergio G. Castillo-Vargasmachuca ◽  
...  
Keyword(s):  
Gulf Of California ◽  
Size Structure ◽  
Coastal Lagoons ◽  
Low Frequency ◽  
Fishing Effort ◽  
Double Ring ◽  
Northwest Mexico ◽  
Fishing Gears ◽  
Fishery Cooperatives ◽  
Ring Net

The fishing effort of a Sinaloa crab fishery in the Gulf of California in 2014 was analysed based on fishermen’s interviews, official catches and permits, and information from a sample of fishing logbooks from five fishery cooperatives operating in four coastal lagoons that contained the daily catch from individual fishing trips. Unauthorized gear, a double-ring net (DR), was used most frequently (>70% of the fishers) for crab fishing, although authorized single-ring nets and Chesapeake traps (CT) were also used with low frequency. The estimated fishing effort was 641 boats/day in the four coastal lagoons, which was 34% more than authorized, and 818 boats/day were employed in all of Sinaloa. A total of 57 479 fishing gears were estimated for the study area, which was 49.9% greater than the maximum authorized number, and 80 822 nominal fishing gears were estimated for the entire Sinaloa crab fishery, 14.15% more than the total gear limit (70 800). The size of the mesh used in the gear was smaller than the authorized limit of 76 mm, and >50% of the catches included crabs of unlawful size. It is argued that the effort must be regulated in terms of the number of vessels, per unit time, and not the number of gears. The information from this study demonstrates a failure to monitor compliance with current regulations and thus means that other strategies for the sustainable management of the fishery, such as co-management, should be tested.

Dominance patterns in macroalgal and phytoplankton biomass under different nutrient loads in subtropical coastal lagoons of the SE Gulf of California

2013 ◽  
Vol 77 (1-2) ◽  
pp. 274-281 ◽  
Author(s):  
F. Páez-Osuna ◽  
A. Piñón-Gimate ◽  
M.J. Ochoa-Izaguirre ◽  
A.C. Ruiz-Fernández ◽  
G. Ramírez-Reséndiz ◽  
...  
Keyword(s):  
Phytoplankton Biomass ◽  
Gulf Of California ◽  
Coastal Lagoons ◽  
Nutrient Loads

Precipitation nutrients in the open and under two forests in Minnesota

1977 ◽  
Vol 7 (1) ◽  
pp. 112-119 ◽  
Author(s):  
Elon S. Verry ◽  
D. R. Timmons
Keyword(s):  
Forest Floor ◽  
Black Spruce ◽  
Inorganic Nitrogen ◽  
Annual Precipitation ◽  
Nutrient Inputs ◽  
Nutrient Input ◽  
Forest Canopies ◽  
North Central ◽  
Annual Amount ◽  
Total P

Concentrations of N, P, K, Ca, Mg, and Na were measured in rain and snow in the open, and in throughfall and stemflow under black spruce and aspen forests in north-central Minnesota. Concentrations of total P in rain and black spruce throughfall were inversely related to storm size. Annual precipitation nutrient inputs to the forest floor were calculated for each site. In general, nutrient contributions from snow were less than 10% of the annual nutrient input from precipitation at each site, and differences in snow nutrient input between sites were minimal. Rainfall nutrient input differed significantly between sites. Rain and snow passing through both forest canopies were enriched with nutrients except inorganic nitrogen. Total annual nutrients added to the forest floor under the black spruce stand averaged 1.7 times that added in the open; the annual amount added under the aspen stand averaged 5.2 times that added in the open.

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