An importance of soil humidification in forming of avifauna of arboreal plantation in the Biosphere reserve «Askania Nova» (un-reproductive period)

2016 ◽  
Vol 27 (3-4) ◽  
pp. 55-69
Author(s):  
M. A. Listopadsky

With gradient analysis investigated the role of soil moisture in the formation of the modern population of birds in the reserve forest plantations. Soil moisture was divided into seven grades. For this purpose used grass cover and the coefficient of local moistening. His proposed PhD L. P. Travleev. This method allows knowing the degree of influence of soil moisture at the birds. We analyzed birds species composition, population, placement in space and power of influence factors (soil moisture). Investigations were carried out on the territory of the Biosphere Reserve «Askania Nova». We studied the birds which live in the reserve at the end of the summer, autumn and winter. This happened from 2006 to 2013 years. Specially was studied as permanently specific form of birds is found in a particular humidity. The degree of coupling was studied using the amount of information that transmits to the local bird humidification. For 68 species of birds are the options of the population density, coefficient koligatsii and data communication with the seven variants of soil moisture. For all kinds of set information «price» of each option dampening that contributes to the formation of a particular community of birds. Thus, the defined contribution to the formation of soil moisture forest bird communities. Species representation and density gradient within the test moisture is not in direct linear relationship from moisture and ranges from 11 (very coldly) to 50 species (moist soil). The density of the community varies from 0,5 birds / hectare (very dry) to 269 birds / hectare (fresh soil). The strongest link between the information and the formation of moisture gradient structure avifauna is typical in a fresh soil – bird on the edge, and wet – forest representatives. These types of humidification function is performed starting in the formation of two major blocks dendrophilous community. The steppe birds give way to forest representatives when the soil slightly moist. The main conclusion of our study includes the following: than wetter the soil the more species of birds lives in the forest; some graduation humidity are the most important for separate species of birds; it is very important for birds, there are places where one can drink water. Further invasive alien species can occur where the soil is moist. Forest with dry soil is already fully occupied by birds.

Crustaceana ◽  
2015 ◽  
Vol 88 (6) ◽  
pp. 657-673 ◽  
Author(s):  
Maria L. Fidalgo ◽  
Paulo Santos ◽  
Cláudia Ferreira ◽  
Andreia Silva

This paper reports population dynamics, growth, and reproductive features ofAtyaephyra desmarestii(Millet, 1831) from the estuary of the River Minho. Also, data were compared to information available from its distribution range. Samples were taken monthly between October 2010 and September 2011. Males were less abundant and smaller than females. The growth pattern showed hardly any increase during the autumn and winter, but a fast increase in size was recorded in spring, followed by slower growth in summer. The life span was 11-12 months. The reproductive period was from April to August, and mean fecundity reached 643 ± 254 eggs/female. Juveniles started to appear in July and a strong recruitment occurred in summer and autumn. The ecological relevance of the shrimp supports the need of obtaining further and more specific knowledge on the relationship between geographical distribution and water quality. Our results coupled with longer time series in different localities will be essential to the conservation of the species.


Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3450 ◽  
Author(s):  
Haider Jawad ◽  
Rosdiadee Nordin ◽  
Sadik Gharghan ◽  
Aqeel Jawad ◽  
Mahamod Ismail ◽  
...  

The use of wireless sensor networks (WSNs) in modern precision agriculture to monitor climate conditions and to provide agriculturalists with a considerable amount of useful information is currently being widely considered. However, WSNs exhibit several limitations when deployed in real-world applications. One of the challenges faced by WSNs is prolonging the life of sensor nodes. This challenge is the primary motivation for this work, in which we aim to further minimize the energy consumption of a wireless agriculture system (WAS), which includes air temperature, air humidity, and soil moisture. Two power reduction schemes are proposed to decrease the power consumption of the sensor and router nodes. First, a sleep/wake scheme based on duty cycling is presented. Second, the sleep/wake scheme is merged with redundant data about soil moisture, thereby resulting in a new algorithm called sleep/wake on redundant data (SWORD). SWORD can minimize the power consumption and data communication of the sensor node. A 12 V/5 W solar cell is embedded into the WAS to sustain its operation. Results show that the power consumption of the sensor and router nodes is minimized and power savings are improved by the sleep/wake scheme. The power consumption of the sensor and router nodes is improved by 99.48% relative to that in traditional operation when the SWORD algorithm is applied. In addition, data communication in the SWORD algorithm is minimized by 86.45% relative to that in the sleep/wake scheme. The comparison results indicate that the proposed algorithms outperform power reduction techniques proposed in other studies. The average current consumptions of the sensor nodes in the sleep/wake scheme and the SWORD algorithm are 0.731 mA and 0.1 mA, respectively.


2012 ◽  
Vol 263-266 ◽  
pp. 1447-1452
Author(s):  
Hong Wei Zhang ◽  
Wen Juan Zhang ◽  
Xue Feng Han

With data quantity increasing dramatically and signal transmission period becoming more and more fast, the media access control delay has proved to be one of the main influence factors of CAN network real-time. Firstly, an equivalent numerical simulation model of CAN bus network is built to derivate the mathematical expression of media access control delay. Secondly, optimization measures are further proposed to improve the data communication real-time. At last, the optimization measures tested by experiments are proved to be correct and effective.


2011 ◽  
Vol 91 (7) ◽  
pp. 1395-1401 ◽  
Author(s):  
Daniela da Silva Castiglioni ◽  
Paloma Joana Albuquerque de Oliveira ◽  
Josivan Soares da Silva ◽  
Petrônio Alves Coelho

This study was carried out in order to provide basic information on the population ecology of the crab Sesarma rectum in the Ariquindá River mangrove, Tamandaré, State of Pernambuco, Brazil. The population was analysed with regard to the following aspects, in particular: the size-class frequency distribution of carapace width (CW), mean body size (CW) of males and females, morphological sexual maturity, sex-ratio, reproductive period, and recruitment. Samples were collected monthly from April 2008 through to March 2009; the crabs were collected manually, with a capture effort by one person for 30 minutes, during low tide. The specimens obtained were measured for CW, length of the propodus of males, and abdomen width of females; and the sex and ovigerous condition were noted. Altogether, we obtained 511 specimens (132 juvenile and 137 adult males, and 171 juvenile and 71 adult females, of which 32 were ovigerous). The median CW of males (16.15 mm) was significantly larger than that of females (13.82 mm) (P < 0.05). The size at morphological sexual maturity was 15.73 mm in males and 16.71 mm in females. The sex-ratio for the total of specimens analysed was 1.11:1 (male:female) (P > 0.05). The sex-ratio by size-class showed an anomalous pattern, with a greater abundance of males in the larger size-classes. The reproductive period was continuous and the highest frequency of ovigerous females was recorded in the spring and summer. The major pulse of recruitment occurred during autumn and winter, which is related to greater reproductive activity during the warmer months of the year.


Water ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1596 ◽  
Author(s):  
Mohamed A. B. Abdallah ◽  
Nicole Durfee ◽  
Ricardo Mata-Gonzalez ◽  
Carlos G. Ochoa ◽  
Jay S. Noller

An enhanced understanding of plant water uptake is critical for making better-informed management decisions involving vegetative manipulation practices aimed to improve site productivity. This is particularly true in arid and semiarid locations where water is a scarce, yet precious commodity. In this project, we evaluated the interannual and seasonal variability of soil moisture and transpiration in sapling, juvenile, and mature western juniper (Juniperus occidentalis) trees in a semiarid rangeland ecosystem of central Oregon, USA. Transpiration levels were greatest in mature juniper trees in an untreated juniper watershed (Jensen WS), while the lowest transpiration levels were observed in juniper saplings in a treated watershed (Mays WS) where most mature juniper trees were removed in 2005. Significant differences (p ≤ 0.05) in leaf water potential levels observed between predawn and midday readings for all juniper growth stages indicated water is lost over the course of the day. Results showed seasonal precipitation was highly variable over the course of the study (2017 through 2019) and this was reflected in soil water available for tree uptake. This resulted in considerable intra- and inter-annual variation in transpiration. In years with greater winter precipitation amounts (2017 and 2019), juniper transpiration rates were highest during the summer, followed by spring, autumn, and winter. On average, transpiration rates during the summer in the wettest (329 mm) year 2017 were 115 and 2.76 L day−1 for mature and sapling trees, respectively. No data were collected for juvenile trees in 2017. In the drier (245 mm) year 2018, higher transpiration rates were observed in the spring. On average, spring transpiration rates were 72.7, 1.61, and 1.00 L day−1 for mature, juvenile, and sapling trees, respectively. Study results highlight the sensitivity of western juniper woodlands to variations in seasonal precipitation and soil moisture availability.


Microbiology ◽  
2000 ◽  
Vol 81 (1) ◽  
pp. 7-14 ◽  
Author(s):  
A. G. Khan

The incidence of mycorrhizas in the roots and Endogone spores in rhizosphere soil of 52 xerophytes, 21 halophytes and 16 hydrophytes from Pakistan was investigated. Vesicular-arbuscular mycorrhizas were of general occurrence in all plants examined except hydrophytes and members of the families Urticaceae, Casuarinaceae, Nyctaginaceae, Portulaceae, Caryophyllaceae, Amaranthaceae, Chenopodiaceae, Capparaceae, Oleaceae, Elaeagnaceae, Zygophyllaceae, Tamaricaceae, Euphorbiaceae and Palmae. Mycorrhizas were found mainly in the surface and subsurface horizons of the soil, and they were much less abundant in the deeper layers, although the abundance of Endogone spores did not decrease with depth. Endogone spores were rare in permanently waterlogged soils, which suggested that soil moisture affected spore number. Most other soil samples contained Endogone spores, including some from rhizospheres of non-mycorrhizal plants. In some soils an increase in spore numbers was recorded in the autumn and winter and a decrease in the spring and summer.


Agriculture ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 245
Author(s):  
Sarah Glatzle ◽  
Sabine Stuerz ◽  
Marcus Giese ◽  
Mariana Pereira ◽  
Roberto Giolo de Almeida ◽  
...  

Integrated-crop-livestock-forestry (ICLF) systems are currently promoted as a measure for sustainable intensification of agricultural production. However, due to complex interactions among ICLF components, we are still lacking evidence about the system’s resilience regarding water availability, especially for regions characterized by pronounced wet and dry seasons and frequent droughts. For a mature ICLF system in the Cerrado biome of central-west Brazil comprising rows of eucalyptus trees (Eucalyptus grandis x Eucalyptus urophylla, H13 clone) at a spacing of 22 m in combination with Brachiaria brizantha cv. BRS Piatã pasture we continuously measured soil moisture (SM) until 1 m depth and supported this data with measurements of photosynthetically active radiation (PAR) and aboveground green grass biomass (AGBM) across transects between the tree rows for almost two years. Across the seasons a distinct gradient was observed with SM being lower close to the tree rows than in the space between them. During winter SM decreased to critical values near the tree lines in the topsoil. During spring and summer, incident PAR was 72% and 86% lower close to the trees than at the center point. For autumn and winter PAR was more evenly distributed between the tree rows due to inclination with notably up to four times more radiation input near the tree lines compared to spring and summer. AGBM showed a clear distribution with maximum values in the center and about half of the biomass close to the tree rows. Our data suggest that, restrictions in AGBM accumulation shifted among seasons between water limitations in winter and light limitations during summer. Interestingly, SM changes during wetting and drying events were most pronounced in subsoils near the tree rows, while the topsoil showed much less fluctuations. The subsoil in central position showed the lowest SM dynamics in response to drought maintaining a relative high and constant SM content, therefore functioning as important water reservoirs likely improving the resilience of the system to drought stress. Results of this study could help to improve management and the design of ICLF systems in view of sustainability and resistance to (water) crises but should be further supported by in depth analysis of soil water dynamics as affected by climate gradients, soil types and different management practices.


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