scholarly journals Long-Term Study of the Relationship between Precipitation and Aquatic Vegetation Succession in East Taihu Lake, China

Scientifica ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Yehui Zhang ◽  
Na Yang ◽  
Jiawei Xu ◽  
Yixing Yin
Keyword(s):  
Water Level ◽  
Aquatic Plants ◽  
Aquatic Vegetation ◽  
Taihu Lake ◽  
Vegetation Succession ◽  
Annual Rainfall ◽  
Dry Period ◽  
Long Term Study ◽  
The Relationship

Based on long-term rainfall measurements (1956–2012), water level records (1956–2006), and aquatic plants field survey data (1960–2014), the relationship between precipitation and aquatic vegetation succession in east Taihu Lake, China, is studied. Neither abrupt changes nor any trends were found in the annual rainfall series in Taihu Lake during the studied period (1956–2012). However, for seasonal variations, statistically significant decreases are found in spring and autumn, while the rainfall in winter exhibits statistically significant increase. No significant trend was obtained in summer. A “dry” period was detected in our studied period (1963/1964~1978/1979). Total annual rainfall was significantly positively correlated to the number of rain-days (r=0.59) and the water level (r=0.84). Our results indicate that the variations of rainfall and water level may have an impact on the aquatic plants in Taihu Lake. The dry period may be not suitable for the growth of the aquatic plants. All aquatic plants in Taihu Lake were dramatically reduced in the dry period, especially for submerged macrophytes and floating-leaf macrophytes. Our results may be helpful for the aquatic restoration in the future.

scholarly journals ESTIMATION OF EFFICIENCY OF CONSTRUCTION OF AGRO-PHYTOCENOSES AND FERTILIZER OF THE OIL RADISH ON THE BASIS OF THE MODULAR-VITALITY METHOD

2019 ◽  
pp. 54-78
Author(s):  
Yaroslav Tsytsiura
Keyword(s):  
Plant Density ◽  
Morphological Characters ◽  
Climatic Conditions ◽  
Morphological Integration ◽  
Plant Oil ◽  
Long Term Study ◽  
Relationship Of ◽  
The Relationship ◽  
Fertilizer Rates

The article presents the results of a long-term study of the features of the phytocenology of agrophytocenoses of oil radish using different methods for assessing their condition and studying the tactics of the plant vitality strategy. A comprehensive assessment was made of the effect of changes in row spacing, seeding rates and fertilizer rates on the formation of various plant morphotypes, the variability of morphological characters and the general characteristics of plant viability. Three idiotypes of the plant oil radish were identified in a vertical study of agrophytocenosis, on the basis of which a detailed analysis of the variability of each group and a statistical assessment of the reliability of its existence were carried out. The features of the morphological integration of each tier are analyzed and its impact on the formation of the overall field productivity is evaluated. Based on the modular and vitality grouping, the effectiveness and feasibility of combining various options for plant density and fertilizer in the range of 30-90 kg of active substance per 1 ha were evaluated. Conclusions are drawn about the desired model of agrophytocenosis of oil radish based on the characteristics of its vital tactics and the goals of its growing. Grouping was carried out according to a variety of morphological traits of plants in the population and the possibilities of applying the basic patterns of phytocenology in their application to radish oilseed plants were evaluated. Through the use of regression analysis, the influence of climatic conditions on the formation of various morphological types of plants and the nature of the relationship of plants of oil radish in cenoses of various densities against the background of various fertilizer options has been evaluated. The main promising areas for further research on the peculiarities of creating highly productive and highly adaptable agrophytocenoses of oil radish have been outlined.

Mechanisms of policy failure: Boston’s 2024 Olympic bid

Urban Studies ◽  
2017 ◽  
Vol 55 (15) ◽  
pp. 3369-3384 ◽  
Author(s):  
Eva Kassens-Noor ◽  
John Lauermann
Keyword(s):  
Turning Point ◽  
Term Study ◽  
City Governments ◽  
Policy Failure ◽  
Long Term Study ◽  
Power Shift ◽  
Opposition Movements ◽  
Political Economic ◽  
The Relationship

Planning for mega-events such as the Olympics is at a turning point. There has been a power shift in the relationship between cities and the International Olympic Committee towards the former. This shift is based on the emergence of anti-bid opposition movements; the increasing complexity of bidding; demands for locally relevant legacies; and a changing political economic relationship between citizens, city governments and sports federations. Our paper draws on a long-term study of Boston’s failed bid to host the 2024 Summer Olympics, based on an ethnography within the bidding corporation and interviews with pro- and anti-bid stakeholders. We lay out the reasons why the Boston bid failed, and conclude that bid failure involves factors that work against elitist powers and towards democratic beneficiaries.

Sedimentary Cladocera as indicators of past water-level changes in shallow northern lakes

2011 ◽  
Vol 75 (3) ◽  
pp. 430-437 ◽  
Author(s):  
Liisa Nevalainen ◽  
Kaarina Sarmaja-Korjonen ◽  
Tomi P. Luoto
Keyword(s):  
Water Level ◽  
Lake Level ◽  
Water Levels ◽  
Sediment Record ◽  
Inference Model ◽  
Water Level Changes ◽  
Long Term Changes ◽  
Lower Water Level ◽  
The Relationship

AbstractThe usability of subfossil Cladocera assemblages in reconstructing long-term changes in lake level was examined by testing the relationship between Cladocera-based planktonic/littoral (P/L) ratio and water-level inference model in a surface-sediment dataset and in a 2000-yr sediment record in Finland. The relationships between measured and inferred water levels and P/L ratios were significant in the dataset, implying that littoral taxa are primarily deposited in shallow littoral areas, while planktonic cladocerans accumulate abundantly mainly in deepwater locations. The 2000-yr water-level reconstructions based on the water-level inference model and P/L ratio corresponded closely with each other and with a previously available midge-inferred water-level reconstruction from the same core, showing a period of lower water level around AD 300–1000 and suggesting that the methods are valid for paleolimnological and -climatological use.

Haemoproteusinfected birds have increased lifetime reproductive success

Parasitology ◽  
2015 ◽  
Vol 142 (8) ◽  
pp. 1033-1043 ◽  
Author(s):  
M. ZYLBERBERG ◽  
E. P. DERRYBERRY ◽  
C. W. BREUNER ◽  
E. A. MACDOUGALL-SHACKLETON ◽  
J. M. CORNELIUS ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Lifetime Reproductive Success ◽  
Parasitic Infections ◽  
Host Fitness ◽  
Return Rates ◽  
Long Term Study ◽  
In The Wild ◽  
The Impact ◽  
The Relationship

SUMMARYThe impact of haematozoan infection on host fitness has received substantial attention since Hamilton and Zuk posited that parasites are important drivers of sexual selection. However, short-term studies testing the assumption that these parasites consistently reduce host fitness in the wild have produced contradictory results. To address this complex issue, we conducted a long-term study examining the relationship between naturally occurring infection withHaemoproteusandPlasmodium, and lifetime reproductive success and survival of Mountain White-crowned Sparrows. Specifically, we tested the hypothesis that birds infected with haematozoan parasites have reduced survival (as determined by overwinter return rates) and reproductive success. Contrary to expectation, there was no relationship betweenHaemoproteusandPlasmodiuminfection and reproduction or survival in males, nor was there a relationship betweenPlasmodiuminfection and reproduction in females. Interestingly,Haemoproteus-infected females had significantly higher overwinter return rates and these females fledged more than twice as many chicks during their lifetimes as did uninfected females. We discuss the impact of parasitic infections on host fitness in light of these findings and suggest that, in the case of less virulent pathogens, investment in excessive immune defence may decrease lifetime reproduction.

Assessment of the impact of water parameters on the flow rate of ceramic pot filters in a long-term experiment

2015 ◽  
Vol 15 (6) ◽  
pp. 1425-1432 ◽  
Author(s):  
C. Salvinelli ◽  
A. C. Elmore
Keyword(s):  
Flow Rate ◽  
Water Production ◽  
Premature Failure ◽  
Initial Flow ◽  
Flow Rates ◽  
Treated Water ◽  
Long Term Study ◽  
The Impact ◽  
The Relationship

Poor water quality is a major contributing factor to disease in developing countries. Silver-coated ceramic pot filters (CPFs) are a relatively common form of household water treatment system (HWTS) representing an effective and sustainable technology for poor communities. Water production seems to be the major limiting factor of the CPF's lifetime and sustainability since low flow rates do not produce an adequate daily volume of treated water. This paper describes a long-term study of CPF flow rates under controlled conditions using three different water sources. The relationship between water characteristics and flow rate was assessed with the intent of identifying the principal parameters that impact CPF water production. The study concluded that turbidity seems to be the principal indicator in determining CPF lifetime in terms of quantity of treated water. There is no evidence that biological activity also contributes to premature failure of CPFs and the data did not indicate that chemical precipitation is responsible for the filter clogging. Manufacturers commonly conduct initial flow rate tests using clear water as a measure of quality assurance. However, the relationship between initial flow rate and average flow rate during the lifetime of the CPF should be further studied.

A LONG TERM STUDY ON INITIAL ORIENTATION IN SAND MARTINS (RIPARIA RIPARIA)

Behaviour ◽  
1999 ◽  
Vol 136 (10-11) ◽  
pp. 1311-1323 ◽  
Author(s):  
Dimitri Giunchi ◽  
Natale Emilio Baldaccini ◽  
Emanuele Mongini
Keyword(s):  
Initial Orientation ◽  
Term Study ◽  
Causal Factors ◽  
Compass Direction ◽  
Order Analysis ◽  
Riparia Riparia ◽  
Long Term Study ◽  
The Relationship ◽  
Homing Direction

AbstractOver a period of 18 years sand martins (Riparia riparia) were displaced from their breeding colonies and released to investigate the relationship between distance of displacement and initial orientation. The results show significant homeward orientation at the shortest distances of displacement (7.1-18.2 km, series A), but not over longer distances (49-180 km, series B and C). Birds displaced over 49 km from their breeding colonies only seldom show homeward directedness, while pseudo-pooling and second order analysis of their directional choices seem to indicate the tendency to fly in a given compass direction. Possible causal factors that can induce this behaviour in sand martins are discussed, taking into account not only local biasing factors but also the existence of a so called preferred compass direction. These data show that sand martins are able to determine the correct homing direction inside a probably familiar area. The response over longer distances indicates difficulties in determining the appropriate homing course at takeoff.

The Relationship between Suicide and Five Climate Issues in a Large-scale and Long Term Study in Japan

2012 ◽  
Vol 61 (5) ◽  
pp. 532-537 ◽  
Author(s):  
K Inoue ◽  
Y Nishimura ◽  
Y Fujita ◽  
Y Ono ◽  
T Fukunaga
Keyword(s):  
Large Scale ◽  
Term Study ◽  
Long Term Study ◽  
The Relationship

scholarly journals Satellite Imageries and Field Data of Macrophytes Reveal a Regime Shift of a Tropical Lake (Lake Ziway, Ethiopia)

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 396
Author(s):  
Yohannes Tefera Damtew ◽  
Boud Verbeiren ◽  
Aymere Awoke ◽  
Ludwig Triest
Keyword(s):  
Surface Water ◽  
Water Level ◽  
Regime Shift ◽  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Aquatic Vegetation ◽  
Meteorological Data ◽  
Water Area ◽  
Ethiopian Rift

Lake Ziway is one of the largest freshwater lakes located in the central Ethiopian rift valley. The lake shoreline is dominated by macrophytes which play an important role in immobilizing run-off pollution, stabilize sediments and support biodiversity. Monitoring the spatio-temporal changes of great lakes requires standardized methods. The aim of this study was to assess the current and long-term trends of macrophyte distribution, surface water area and the water level of Lake Ziway using remote sensing images from 1986 to 2016 with additional hydro-meteorological data. A supervised image classification with classification enhancement using Normalized Difference Aquatic Vegetation Index (NDAVI) and Normalized Difference Vegetation Index (NDVI) was applied. The classification based on NDAVI revealed eight target classes which were identified with an overall producer’s accuracy of 79.6%. Contemporary open water and macrophyte fringes occupied most of the study area with a total area of 407.4 km2 and 60.1 km2, respectively. The findings also revealed a regime shift in the mean water level of the lake and a decline in macrophyte distribution. The long-term water surface area of Lake Ziway also decreased between 1986 and 2016. The changes in water level could be explained by climate variability in the region and strong anthropogenic disturbance. A decline in water level was also associated with lowered surface water area, lakeward retreated macrophyte fringes and enhanced landward encroachment of mudflats, and resulted in a succession of macrophytes with semi-terrestrial vegetations.

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