Search

Start Over Coverage 64-72 Harvested from CDK

4. Remote-sensing based groundwater recharge estimates in the Danube-Tisza sand plateau region of Hungary

Creator:
Szilágyi, József, Kovács, Ákos, and Józsa, János
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
groundwater recharge, MODIS data, Danube-Tisza sand plateau, doplňovanie podzemných vôd, MODIS, and plató Dunaj-Tisa
Language:
Slovak
Description:
Mean annual recharge in the Danube-Tisza sand plateau region of Hungary over the 2000-2008 period was estimated at a 1-km spatial resolution as the difference of mean annual precipitation (P) and evapotranspiration (ET). The ET rates were derived from linear transformations of the MODIS daytime land surface temperature (Ts) values with the help of ancillary atmospheric data (air temperature, humidity, and sunshine duration). The groundwater under the sand plateau receives about 75 ± 50 mm of recharge annually (the plus/minus value is the associated error, resulting from an assumed 5% error in both the P and ET values), which is about 14 ± 9 % of the regional mean annual P value of 550 mm. The largest continuous region with elevated recharge rates (about 180 ± 50 mm a-1 or 30 ± 8 % of P) occur in the south-western part of the plateau due to more abundant precipitation (around 580 mm a-1), while recharge is the smallest (about 40 ± 40 mm a-1 or 7 ± 7 % of P) under forested areas. Typically, lakes, wetlands, river valleys, and certain afforested areas in the north-central part of the region act as discharge areas for groundwater. and Priemerný ročný úhrn doplňovania podzemných vôd plošiny zloženej z pieskov medzi riekami Dunaj a Tisa s rozlíšením 1 km, pre roky 2000-2008 bol určený ako rozdiel medzi priemerným ročným úhrnom zrážok (P) a evapotranspiráciou (ET). ET bolo určené z lineárnej transformácie teploty povrchu počas dňa (Ts) získanej systémom MODIS pomocou údajov o vlastnostiach atmosféry (teplota vzduchu, vlhkosť vzduchu a trvanie slnečného svitu). Podzemná voda pod pieskovým masívom dostáva ročne asi 75 ± 50 mm vody (znamienka plus/mínus znamenajú chybu, vyplývajúcu z predpokladanej 5% chyby hodnôt P a ET), ktorá je asi 14 ± 9 % regionálnej priemernej ročnej hodnoty P, ktorá je 550 mm. Najväčšia spojitá oblasť so zvýšeným doplňovaním podzemnej vody (približne 180 ± 50 mm za rok alebo 30 ± 8 % P) sa nachádza v juhozápadnej časti plató a je dôsledkom vyššieho ročného úhrnu zrážok (okolo 580 mm), doplňovanie je nižšie v zalesnených oblastiach (okolo 40 ± 40 mm, alebo 7 ± 7 % P). Jazerá, mokrade, rieky a niektoré zalesnené oblasti v strednej a severnej časti tejto oblasti drénujú podzemné vody.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

5. Soil moisture dynamics in levees during flood events - variably saturated approach

Creator:
Zumr, David and Císlerová, Milena
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
floods, river embankment, earth dam, unsaturated soil, vadose zone, seepage modelling, soil water dynamics, Richards’ equation, záplavy, protipovodňová hráz, sypaná zemní hráz, nenasycená půda, vadózní zóna, modelování průsaku, vodní režim půd, and Richardsova rovnice
Language:
Slovak
Description:
Growing occurrence of extreme floods in the Czech Republic has attracted attention to the security of protective earthfill embankments along the rivers. A suddenly increased amount of water on the waterside slope of the embankment may have destroying or even catastrophic consequences. Predictions of seepage patterns through the earth body are usually done considering the saturated flow beneath the free water level only, neglecting the saturated-unsaturated character of the soil water dynamics within earthfill dams. The importance of water dynamics within an earth dam is known and may be addressed using numerical simulation models. In this study the solution based on transient simulation of seepage through protection levee using saturated-unsaturated theory is presented. Simulations were carried out by a two-dimensional numerical model based on Richards’ equation for water flow in porous medium. It has been shown that proposed approach is, with certain limitations, suitable for large scale engineering applications. and Vyšší pravděpodobnost výskytu extrémních klimatických jevů obrací pozornost k ochraně před následky, které tyto jevy způsobují. Zájem se soustředí na protipovodňové ochranné zemní hráze a jejich bezpečnost při povodních. Výpočet průsaku zemními hrázemi se často omezuje pouze na tu část hráze, která byla plně nasycená vodou, to znamená na plně nasycené proudění. Tento způsob modelování průsaku je dodnes považován za standardní, přestože je velmi limitující. Bez zahrnutí nenasycené části tělesa hráze je zanedbán vliv časově i prostorově proměnlivého pole vlhkostí (např. při infiltraci vody ze srážky) na polohu hladiny. V naší studii je simulováno proudění v tělese hráze s použitím numerického modelu, který umožňuje řešit proudění vody v proměnlivě nasyceném heterogenním pórovitém prostředí, s obecnými okrajovými podmínkami. Výsledky potvrdily, že přístup, který uvažuje proudění i v nenasycené části hráze, lze k řešení průsaků zemními tělesy úspěšně využít.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

6. The canopy rainfall interception in actual and potential distribution of Qinghai spruce (Picea crassifolia) forest

Creator:
Xu, Zhonglin, Feng, Zhaodong, Zhao, Chuanyan, Zheng, Jianghua, Yang, Jianjun, Tian, Fengxia, Peng, Huanhua, Wang, Chao, Peng, Shouzhang, and Sher, Hassan
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Qinghai spruce, actual interception, potential interception, potential distribution, and ecohydrology
Language:
Slovak
Description:
Interception is one of the most underestimated processes in hydrological cycle in arid and semiarid regions. In Qilian Mountains of northwestern arid and semiarid China, the Qinghai spruce (Picea crassifolia) forest plays an important role in the hydrological cycle of the inland Heihe River basin. The historical disturbance of Qinghai spruce forest has resulted in various ecological problems. In order to realize the sustainable development of Heihe River basin, the Chinese government implemented restoration practices for Qinghai spruce in the past three decades. In this study, we estimated the rainfall interception in the actual and potential distribution of Qinghai spruce forest. Some of the important findings include: (1) The interception ratio of rainfall events ranged from 11-51% with a mean value of 27.02%; (2) Totally, 147 Mt of rainfall is intercepted by canopy of actual Qinghai spruce forest, in the projected potential distribution of the forest, totally 407 Mt of rainfall will be intercepted.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

7. Two hemocyte populations in Triatoma infestans: ultrastructural and lectin-binding characterization

Creator:
Hypša, Václav and Grubhoffer, Libor
Format:
print
Type:
model:internalpart and TEXT
Language:
English
Description:
Two distinct hemocyte populations are determined in the hemolymph of the triatomine bug Triatoma infestans Klug, oenocytoids and plasmatocytes, and their independent origin from separate stem cells is shown. Both hemocyte populations differ considerably in their morphology, ultrastructure and lectin-binding properties. While oenocytoids are quite uniform with easily definable cells which do not to bind any assayed lectin, the plasmatocytes are a very polymorphic population possessing several morphological types and displaying a positive reactivity with lectins.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public