Humidity Regimes Research Articles

Neogene aridification of the Northern Hemisphere

Research Article| September 01, 2012 Neogene aridification of the Northern Hemisphere Jussi T. Eronen; Jussi T. Eronen * 1Department of Geosciences and Geography, P.O. Box 64, University of Helsinki, Helsinki FI-00014, Finland2Biodiversity and Climate Research Centre (LOEWE BiK-F), Senckenberganlage 25, D-60325 Frankfurt am Main, Germany *E-mail: Jussi.T.Eronen@helsinki.fi. Search for other works by this author on: GSW Google Scholar M. Fortelius; M. Fortelius 1Department of Geosciences and Geography, P.O. Box 64, University of Helsinki, Helsinki FI-00014, Finland3Institute of Biotechnology, P.O. Box 56, University of Helsinki, Helsinki FI-00014, Finland Search for other works by this author on: GSW Google Scholar A. Micheels; A. Micheels 2Biodiversity and Climate Research Centre (LOEWE BiK-F), Senckenberganlage 25, D-60325 Frankfurt am Main, Germany4Senckenberg Research Institute and Natural History Museum, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany Search for other works by this author on: GSW Google Scholar F.T. Portmann; F.T. Portmann 2Biodiversity and Climate Research Centre (LOEWE BiK-F), Senckenberganlage 25, D-60325 Frankfurt am Main, Germany4Senckenberg Research Institute and Natural History Museum, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany Search for other works by this author on: GSW Google Scholar K. Puolamäki; K. Puolamäki 5HIIT, Department of Computer and Information Science, Aalto University, P.O. Box 15400, FI-00076 Aalto, Espoo, Finland Search for other works by this author on: GSW Google Scholar Christine M. Janis Christine M. Janis 6Department of Ecology and Evolutionary Biology, Brown University, Providence, Rhode Island 02912, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Jussi T. Eronen * 1Department of Geosciences and Geography, P.O. Box 64, University of Helsinki, Helsinki FI-00014, Finland2Biodiversity and Climate Research Centre (LOEWE BiK-F), Senckenberganlage 25, D-60325 Frankfurt am Main, Germany M. Fortelius 1Department of Geosciences and Geography, P.O. Box 64, University of Helsinki, Helsinki FI-00014, Finland3Institute of Biotechnology, P.O. Box 56, University of Helsinki, Helsinki FI-00014, Finland A. Micheels 2Biodiversity and Climate Research Centre (LOEWE BiK-F), Senckenberganlage 25, D-60325 Frankfurt am Main, Germany4Senckenberg Research Institute and Natural History Museum, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany F.T. Portmann 2Biodiversity and Climate Research Centre (LOEWE BiK-F), Senckenberganlage 25, D-60325 Frankfurt am Main, Germany4Senckenberg Research Institute and Natural History Museum, Senckenberganlage 25, D-60325 Frankfurt am Main, Germany K. Puolamäki 5HIIT, Department of Computer and Information Science, Aalto University, P.O. Box 15400, FI-00076 Aalto, Espoo, Finland Christine M. Janis 6Department of Ecology and Evolutionary Biology, Brown University, Providence, Rhode Island 02912, USA *E-mail: Jussi.T.Eronen@helsinki.fi. Publisher: Geological Society of America Received: 20 Dec 2011 Revision Received: 26 Mar 2012 Accepted: 01 Apr 2012 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2012 Geological Society of America Geology (2012) 40 (9): 823–826. https://doi.org/10.1130/G33147.1 Article history Received: 20 Dec 2011 Revision Received: 26 Mar 2012 Accepted: 01 Apr 2012 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Jussi T. Eronen, M. Fortelius, A. Micheels, F.T. Portmann, K. Puolamäki, Christine M. Janis; Neogene aridification of the Northern Hemisphere. Geology 2012;; 40 (9): 823–826. doi: https://doi.org/10.1130/G33147.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Neogene cooling and aridification in the Northern Hemisphere have long been recognized, but there are no studies comparing patterns of aridity gradients or differences between North America and Eurasia. Large herbivorous mammals are an excellent source for understanding large-scale environmental and climatic patterns because their molar crown height (hypsodonty) reflects both habitat and precipitation. The temporal development of hypsodonty in the North American Great Plains is well studied, but both spatial detail and comparisons with patterns in Eurasia are lacking. Here we use a methodology based on community levels of hypsodonty to estimate precipitation during the Neogene (the past 23 Ma). We show that aridification was more profound and occurred ∼5 Ma earlier in North America than in Eurasia. By combining our results with existing climate model output and new sensitivity experiments, we show how these changes were influenced by ocean heat transport and atmospheric circulation patterns. We further suggest that asymmetric dispersal of large mammals between Eurasia and North America was related to the contrasting humidity regimes between the continents. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.

An Evaluation of Four Reference Evapotranspiration Models in a Subtropical Climate

This paper describes a detailed evaluation of the performance and characteristic behaviour of four equations for estimating reference evapotranspiration (ET0) at eight meteorological sites in a subtropical climate. The equations assessed were: Makkink (MK), Turc (TC), Priestley–Taylor (PT) and Hargreaves (HG). The sites were distributed throughout the north of Iran and represent an intermediate humidity regime. The Penman–Monteith (PM) method was chosen as the standard for comparison and calibration of the above—mentioned four equations. Good correlation was found between the ET0 values estimated by each of the four empirical equations and the PM method for all the locations; however MK and TC equations produced considerable underestimations. The performance of the PT and HG equations improved slightly after region-specific coefficients were developed for each equation, and the TC and MK equations were improved greatly. The modified PT equation turned out to be the most precise method, demonstrating superiority over the other methods evaluated (0.48 mm d−1 of root mean square error (RMSE)). Good performance from the modified HG equation (0.53 mm d−1 of RMSE) must be emphasized, given the simplicity of that method, which only requires maximum and minimum air temperature data.

Abiotic factors influence microbial diversity in permanently cold soil horizons of a maritime-associated Antarctic Dry Valley

The McMurdo Dry Valleys collectively comprise the most extensive ice-free region in Antarctica and are considered one of the coldest arid environments on Earth. In low-altitude maritime-associated valleys, mineral soil profiles show distinct horizontal structuring, with a surface arid zone overlying a moist and biologically active zone generated by seasonally melted permafrost. In this study, long-term microenvironmental monitoring data show that temperature and soil humidity regimes vary in the soil horizons of north- and south-facing slopes within the Miers Valley, a maritime valley in the McMurdo Dry Valleys. We found that soil bacterial communities varied from the north to the south. The microbial assemblages at the surface and shallow subsurface depths displayed higher metabolic activity and diversity compared to the permafrost soil interface. Multivariate analysis indicated that K, C, Ca and moisture influenced the distribution and structure of microbial populations. Furthermore, because of the large % RH gradient between the frozen subsurface and the soil surface we propose that water transported to the surface as water vapour is available to microbial populations, either as a result of condensation processes or by direct adsorption from the vapour phase.

Cutaneous water loss and covalently bound lipids of the stratum corneum in nestling house sparrows (Passer domesticus L.) from desert and mesic habitats

Lipids of the stratum corneum (SC), the outer layer of the epidermis of birds and mammals, provide a barrier to water vapor diffusion through the skin. The SC of birds consists of flat dead cells, called corneocytes, and two lipid compartments: an intercellular matrix and a monolayer of covalently bound lipids (CBLs) attached to the outer surface of the corneocytes. We previously found two classes of sphingolipids, ceramides and cerebrosides, covalently bound to corneocytes in the SC of house sparrows (Passer domesticus L.); these lipids were associated with cutaneous water loss (CWL). In this study, we collected adult and nestling house sparrows from Ohio and nestlings from Saudi Arabia, acclimated them to either high or low humidity, and measured their rates of CWL. We also measured CWL for natural populations of nestlings from Ohio and Saudi Arabia, beginning when chicks were 2 days old until they fledged. We then evaluated the composition of the CBLs of the SC of sparrows using thin layer chromatography. We found that adult house sparrows had a greater diversity of CBLs in their SC than previously described. During ontogeny, nestling sparrows increased the amount of CBLs and developed their CBLs differently, depending on their habitat. Acclimating nestlings to different humidity regimes did not alter the ontogeny of the CBLs, suggesting that these lipids represent a fundamental component of SC organization that does not respond to short-term environmental change.

Role of Tribochemistry in Nanowear of Single-Crystalline Silicon

The effects of counter-surface chemistry, relative humidity, and applied normal load on nanowear of single-crystalline silicon were studied with atomic force microscopy. In the absence of humidity, the silicon surface can resist mechanical wear as long as the contact pressure is lower than the hardness of silicon regardless of the counter-surface chemistry (diamond or SiO(2)) and ambient gas type (vacuum, N(2), O(2), air). In these conditions, the sliding contact region is protruded forming a hillock. However, when the relative humidity is higher than ~7%, the hillock formation is completely suppressed and, instead, tribochemical wear of the silicon surface takes place even at contact pressure much lower than the hardness. The tribochemical wear increases drastically in the relative humidity regime where the adsorbed water layer assumes the "solid-like" structure; further increase of wear is small in higher relative humidity regime where the "liquid-like" water layer is formed. It is also noted that the humidity-induced wear occurs only when the counter-surface is SiO(2); but not with the diamond counter-surface. This implies that the interfacial shear of the water-adsorbed SiO(2) surface with a chemically inert counter-surface is not sufficient to initiate the tribochemical wear; both substrate and counter-surface must be chemically reactive. A phenomenological model is proposed to explain the experimental observations.

Effects of climate on the introduction, distribution and biotic potential of parasitoids: Applications to biological control of California red scale

California red scale (CRS) parasitoids of 121 citrus groves belonging to three different Mediterranean-climate ecosystems (inland, coastal and subtropical) of eastern Spain were used as a model to study the effects of climate on composition and distribution of parasitoid communities. Then we evaluate the success of a biocontrol program based on releases of three new CRS parasitoid species. Field surveys were complemented by laboratory trials under simulated common and extreme climate conditions (15, 20, 25 and 30°C combined with 25%, 45% and 65% RH) to know parasitoid’s life-history traits. In the inland area Aphytis melinus was the only parasitoid present, in the coastal it coexisted with Aphytis chrysomphali and in the subtropical also with Encarsia perniciosi. Comperiella bifasciata established in all inland groves where it was released whereas E. perniciosi and Aphytis lingnanensis only in the groves within the subtropical agroecosystem. In the laboratory, the highest intrinsic rate of increase (rm) values for C. bifasciata and E. perniciosi were reached at temperature–humidity regimes typical from inland and subtropical areas respectively. The longevity of both species at different temperature–humidity conditions also reflected their adaptability to dry or humid areas. Our results with CRS endoparasitoids, together with previous studies on Aphytis species, demonstrate the validity of rm analysis at different extreme temperature–humidity combinations to predict the potential areas of distribution of newly introduced organisms. Slight differences in average winter and summer temperatures or relative humidity between neighbor agroecosystems caused large variation in species composition and introduction success ratio.

Reversible anther opening enhances male fitness in a dichogamous aquatic plant Butomus umbellatus L., the flowering rush

We studied reversible anther opening in a dichogamous aquatic plant Butomus umbellatus L. (Butomaceae) to assess its consequence on male fitness. Light microscope observations indicated that stomium breakage was simultaneous in all the anthers within an opening flower; however, detachment of the epidermis and outward bending of the anther wall were asynchronous. SEM observations showed that epidermis cells alternated between orbicular and crinkly shapes in response to absorption and loss of water. This generated centripetal and centrifugal forces which were significant enough to cause inward and outward bending of the anther wall, thus causing opened anthers to close and closed anthers to re-open respectively, depending on relative humidity of the environment. Behaviour of in vitro and in situ anthers from different whorls within a flower was recorded under four regimes of relative humidity or under a water-spraying treatment. The three stages of anther opening namely stomium breakage, epidermis detachment and outward bending of the anther wall were affected differently by moisture levels. Outward bending of anther wall which was responsible for reversible anther opening was mainly dependent on environmental relative humidity levels. Notably, on sunny days, anther re-opening was inhibited at high relative humidity for in vitro anthers, but not for anthers in situ. Reabsorption, rather than evaporation was responsible for reversible anther opening for this aquatic plant. Water-spraying treatment indicated that flowers with re-closed anthers attracted fewer pollinators. Results using pollen stainability and germinability of pollen on stigmas for pollen grains from different treatments also showed the mechanism of reversible anther opening significantly prolonged pollen longevity by maintaining high viability in a simulated rainy. Discontinuous pollen presentation due to reversible anther opening avoided unfavorable pollination environment and pollen loss.

Colonization of Tomato Seedlings by Bioluminescent Clavibacter michiganensis subsp. michiganensis Under Different Humidity Regimes

Tomato bacterial canker, caused by Clavibacter michiganensis subsp. michiganensis, is transmitted by infected or infested seed and mechanically from plant to plant. Wounds occurring during seedling production and crop maintenance facilitate the dissemination of the pathogen. However, the effects of environmental factors on C. michiganensis subsp. michiganensis translocation and growth as an endophyte have not been fully elucidated. A virulent, stable, constitutively bioluminescent C. michiganensis subsp. michiganensis strain BL-Cmm 17 coupled with an in vivo imaging system allowed visualization of the C. michiganensis subsp. michiganensis colonization process in tomato seedlings in real time. The dynamics of bacterial infection in seedlings through wounds were compared under low (45%) and high (83%) relative humidity. Bacteria multiplied rapidly in cotyledon petioles remaining after clip inoculation and moved in the stem toward both root and shoot. Luminescent signals were also observed in tomato seedling roots over time, and root development was reduced in inoculated plants maintained under both humidity regimes. Wilting was more severe in seedlings under high-humidity regimes. A strong positive correlation between light intensity and bacterial population in planta suggests that bioluminescent C. michiganensis subsp. michiganensis strains will be useful in evaluating the efficacy of bactericides and host resistance.

Effects of humid environment on thermal and mechanical properties of a cold-curing structural epoxy adhesive

The effects of exposure to different humid environments in a commercial cold-cured epoxy adhesive were investigated. Samples were exposed up to one month to 55%, 75% and 100% relative humidity (RH) or immersed in liquid water, at a constant temperature (23°C). Weight changes, thermal and mechanical properties before and at different stages of the aging, were discussed.In the examined aging conditions, absorbed water remained below 1% and saturation level was not achieved. Plasticization, reactivation of curing reactions and erasure of physical aging were observed in the specimens subjected to the different humidity regimes, all affecting both the thermal and the mechanical properties of the aged samples: while the Tg was influenced by plasticization mainly at shorter times of exposure and by post-curing at longer treatment times, the mechanical characteristics were less affected by these phenomena. These effects were found more pronounced at humidity levels higher than 75% RH. Doubly hydrogen-bonded water molecules linked to the network also influenced the Tg of the system, while they did not affect noticeably their flexural properties. Finally, the effects of water exposure can be regarded as equivalent to those of a thermal treatment at temperature around the Tg, i.e. both leading to an erasure of the physical aging.

A Proxy for Humidity and Floral Province from Paleosols

We develop a proxy to infer humidity from the geochemistry of paleosols in order to enhance reconstructions of ancient paleoclimate beyond trends in mean annual precipitation. Geochemical transfer functions, developed herein, are used to estimate net primary production and evapotranspiration along three latitudinal transects of modern soils in the coterminous United States. Mean annual precipitation and the degree of chemical weathering are estimated from the major element concentrations in soils. The ratio of evapotranspiration, estimated from our proxy, and mean annual precipitation provides a method of determining the humidity province of ancient climates that is more robust and meaningful than previous methods, and our approach differs from existing methods since both the influx and efflux of moisture are explicitly determined. The required input parameters for application of this proxy are (1) the soil morphology, (2) accurate and complete major element concentration data for the active soil and parent material, and (3) the latitude or mean annual temperature (±5°C) of the soil or paleosol. The correlation coefficient between the measured climate and the modeled climate regime using only the latitude, morphologic, and major element data of soils is . We conclude that this proxy provides a refined determination of humidity and floral regimes that can be applied to paleosols.

The influence of microclimate on foraging and sheltering behaviours of terrestrial isopods: Implications for soil carbon dynamics under climate change

Abstract In south east England climate change is predicted to include decreases in periodicity of rainfall events during summer, resulting in more, longer periods of drought. In many temperate regions these changes will affect foraging strategies of soil animals, including arthropod macro-decomposers such as terrestrial isopods. We investigated activity budgets under drier (50%) and moisture (90%) relative humidity conditions, for three species: Porcellio scaber, Oniscus asellus and Armadillidium vulgare, representing three families, which have different morphological adaptations to the terrestrial environment. In the drier environment all three species spent more time sheltering, less time feeding and less time in other activities. Costs of foraging were estimated by monitoring loss of body mass for 7 h. This loss was twice as high under the lower humidity regime. On the basis of morphological traits, two members of the Oniscidae: O. asellus and Philoscia muscorum, differing in eco-morphological strategies, were predicted to be more susceptible to desiccation than members of the Porcellionidae or Amadillidiidae. Members of the Oniscidae lost mass most quickly and also suffered higher mortality in the drier atmosphere. A cost of spending more time sheltering was that consumption of high quality food by Porcellio scaber was significantly reduced in the drier environment. The trade-off between energy gain by feeding and increased probability of survivorship by sheltering, is illustrated using an isopleth model. Changes in the extent to which the soil fauna will stimulate microbial metabolism and hence soil carbon dioxide emissions, under future conditions of climate change are predicted.

Captive Breeding of Green Tree Python, Chondropython viridis , with Remarks on the Role of This Method for Conservation

The data presented include information about captive breeding results of green tree python, Chondropython viridis : temperature and humidity regimes, cage sizes, clutch size, duration of incubation and first shedding of neonates. Captive breeding of this species could be considered as a model for breeding of tropical rain forest snakes in conservation programs.

Seasonality Directs Contrasting Food Collection Behavior and Nutrient Regulation Strategies in Ants

Long-lived animals, including social insects, often display seasonal shifts in foraging behavior. Foraging is ultimately a nutrient consumption exercise, but the effect of seasonality per se on changes in foraging behavior, particularly as it relates to nutrient regulation, is poorly understood. Here, we show that field-collected fire ant colonies, returned to the laboratory and maintained under identical photoperiod, temperature, and humidity regimes, and presented with experimental foods that had different protein (p) to carbohydrate (c) ratios, practice summer- and fall-specific foraging behaviors with respect to protein-carbohydrate regulation. Summer colonies increased the amount of food collected as the p:c ratio of their food became increasingly imbalanced, but fall colonies collected similar amounts of food regardless of the p:c ratio of their food. Choice experiments revealed that feeding was non-random, and that both fall and summer ants preferred carbohydrate-biased food. However, ants rarely ate all the food they collected, and their cached or discarded food always contained little carbohydrate relative to protein. From a nutrient regulation strategy, ants consumed most of the carbohydrate they collected, but regulated protein consumption to a similar level, regardless of season. We suggest that varied seasonal food collection behaviors and nutrient regulation strategies may be an adaptation that allows long-lived animals to meet current and future nutrient demands when nutrient-rich foods are abundant (e.g. spring and summer), and to conserve energy and be metabolically more efficient when nutritionally balanced foods are less abundant.

Effect of Temperature and Relative Humidity on the Growth of <i>Helminthosporium fulvum</i>

The effects of temperature and relative humidity on the growth of Helminthosporium fulvum were investigated. Various temperature regimes of 10oC, 15oC, 20oC, 25oC, 30oC, 35oC and 40¢aC were used to determine the temperature effect on the growth of H. fulvum. Maximum growth of H. fulvum was obtained at 25¢aC and 30¢aC temperatures. The fungus was also cultured on 100, 92.5, 85, 74 and 32.5% relative humidity regimes. The fungus showed maximum growth at 92.5 and 100% relative humidity. The growth of the fungus was observed to increase with increase in relative humidity and vice versa. There were significant differences (PiÂ0.05) in the growth of the fungus at different temperature and relative humidity regimes. The implication of these findings were discussed

Responses of time of anthesis and maturity to sowing dates and infrared warming in spring wheat

Reliable prediction of the potential impacts of global warming on agriculture requires accurate data on crop responses to elevated temperatures. Controlled environments can precisely regulate temperature but may impose unrealistic radiation, photoperiod and humidity regimes. Infrared warming with automatic control of temperature rise has shown potential for warming field plots above ambient temperatures, while avoiding such biases. In a field experiment conducted at Maricopa, AZ, we assessed the utility of a temperature free-air controlled enhancement (T-FACE) approach by comparing phenology of wheat from a series of six sowing date treatments using T-FACE and an additional nine sowing dates that exposed crops to an exceptionally wide range of air temperatures (<0 °C to >40 °C). The T-FACE treatments were intended to achieve a warming of +1.5 °C during the daytime and +3.0 °C at night; the achieved warming averaged +1.3 °C during daytime and +2.8 °C at night. T-FACE and sowing date treatments had large effects on phenology. A regression-based analysis of simulations with the CSM-CROPSIM-CERES model showed that effects of T-FACE on phenology were similar to what would be expected from equivalent changes in air temperature. However, systematic deviations from the expected 1-to-1 relation suggested that assumed cardinal temperatures for phenology should be revised. Based on the single cultivar and location, it appeared that the base temperature for emergence to anthesis should be reduced from 0 °C to −5 °C, whereas the base temperature for grain filling should be increased from 0 °C to 4 °C and the optimal temperature, from 30 °C to 34 °C. Both T-FACE and extreme sowing date treatments proved valuable for improving understanding of high temperature effects on plant processes, as required for accurate prediction of crop responses to elevated temperatures under climate change.

The effect of relative humidity on the effectiveness of the cyanoacrylate fuming process for fingermark development and on the microstructure of the developed marks

Research has been conducted to establish the effect that changes in relative humidity have on both the effectiveness of the cyanoacrylate fuming technique and the microstructures formed by the polymerisation reaction during the development of the marks. The study investigated 'natural' fingermarks and deliberately groomed eccrine and sebaceous marks, all exposed to relative humidity levels in the range 60-100%. It was found that the optimum level of relative humidity for the development of the most high quality marks is approximately 80%, in accord with current recommendations for operational implementation which are based on previous unpublished work. The eccrine constituents of the fingerprints are most influenced by humidity changes. Three humidity regimes were identified, each giving different polycyanoacrylate microstructures. Humidity levels of 60% give flat, film-like structures whereas in the range 70-90% the characteristic noodle-like structure is formed. At higher humidities, thin, flat thread-like growth is observed with some 'collapsed sphere' structures observed close to pores and significant background development. The noodle-like structures are thought to scatter more light and retain fluorescent dye better than the structures formed at other humidity levels. Sebaceous marks produce a very different polymer microstructure, resembling a flat film with some fine nodular structures.

Effect of temperature and relative humidity on the development and fecundity of Chilo partellus (Swinhoe) (Lepidoptera: Crambidae)

The spotted stemborer, Chilo partellus (Swinhoe) (Lepidoptera: Crambidae), is one of the most important insect pests attacking maize and sorghum in Ethiopia. Recent studies have indicated that the pest is spreading to new locations where it was not reported before. In the current study, laboratory investigations were carried out to determine the combined effect of different levels of relative humidity and temperature regimes on the development and fecundity of C. partellus, as these physical factors are known to play an important role in the life cycle of insects and adaptability to local climate. Developmental time, longevity, potential fecundity and realized fecundity of C. partellus were measured under controlled conditions. Three temperature regimes (22°C, 26°C and 30°C) and three relative humidity levels (40%, 60% and 80%) were tested. It was found that temperature, relative humidity (RH) and their interaction significantly affected the developmental time, adult longevity, potential fecundity and realized fecundity of the pest. Developmental time was inversely related to temperature. Mean duration of C. partellus life cycle was 70.2 days at 22°C and 80% RH, whereas it took only 26.5 days to complete its life cycle at 30°C and 40% RH. Male and female longevity were similar in most cases. The adult life span ranged between 6.9-11.1 days at 22°C and 3.1-7.2 days at 30°C for different levels of relative humidity. The most suitable conditions for C. partellus development and fecundity were 26-30°C temperatures regimes and 60-80% RH levels.

Use of a soil moisture network for drought monitoring in the Czech Republic

Since 2000, the network of stations that make up the Czech Hydrometeorological Institute (CHMI) has measured the soil moisture content at the 0- to 0.9-m layer using sensors placed within the natural soil profile under closely cropped grass cover. Using information from 8 years of continuous observation at seven stations throughout the Czech Republic, we verified the usefulness of the Soil Moisture Index (SMI). The SMI is a potentially useful index for calculating the water deficit in the Czech Republic and Central Europe. During this period, a statistically significant decrease in moisture content was detected, and negative SMI values predominated. There were frequent occurrences of flash drought, defined as a very rapid decline in soil moisture during a 3-week period. The CHMI can use SMI values below −3 in the Integrated Warning Service System. The routine calculation of SMI values can alert agricultural producers to the development of flash drought conditions and provide them with information regarding the effectiveness of recent rainfall events. An increase in soil moisture, in contrast, could serve as a warning sign for hydrology because it creates the preconditions for flooding. The complex study of soil humidity regimes is becoming more significant in connection with current global climatic change warnings in hydrological cycles.

Modeling Autoregressive Models in Cool Island Effects associated with Remote Telemeter Technology (ASTER) in Taiwan: A GIS Approach

Abstract A microclimate is the unique climate of a small-scale region, such as a field or parts of urban or rural areas. The weather variables in a microclimate include temperature, wind, humidity, land forms, and water regimes. In Northern Taiwan's Taoyuan County, irrigation ponds take a long time to heat up during the summer months, keeping these rural areas cooler than surrounding urbanized areas. Based on Geographic Information System (GIS) layers associated with Digital Terrain Modeling (DTM), along with Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) images, this paper examines temperature variables in four counties/cities in Taiwan for the past century. Urban development is found to have contributed to temperature increases, but an understanding of the cooling mechanism is still incomplete. Temperatures in the Taoyuan tableland have declined, at odds with trends in other areas in Taiwan as well as on a global scale. In Taoyuan, the Times-Series Regression Model was used to extrapolated a downward trend from a mean current temperature of 21.3 °C currently down to 19.72 °C in 2099, assuming the area of irrigation ponds remain unchanged.

Influence of Nutrient Source and Growing Environment on Tissue Elemental Concentration and Yield of Cos Lettuce in Hydroponic Culture

Complete fertilizers formulated for fertigation and soil application are commonly used in hydroponic production. However, these are unsuitable for hydroponic culture of many crops because of imbalances in mineral nutrient composition. Currently, research information about the effect of nonhydroponic fertilizers and the confounding effects of crop type and culture condition on crop yield is limited. The influence of mineral nutrient source (FERT) and growing environment (two controlled environment hydroponic greenhouses; CEHG) with different temperature and relative humidity (RH) regimes on mineral elemental concentration and yield of cos lettuce (Lactuca sativa L. var. longifolia Lam.), cv. Cimmaron, were determined in a nutrient film technique (NFT) hydroponic culture. With the exception of calcium, both CEHG and FERT had a significant effect on the tissue concentration of all the macronutrients, and the concentration of micronutrients in lettuce tissue were optimum, regardless of FERT and CEHG, except for Fe (APHN and CAMG) and Mo (APHN). However, low tissue concentration of macronutrients may have contributed to reducing the marketable yield, which was also significantly affected by FERT.