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991.
992.
Modelling and predicting the potential habitat and future range expansion of invasive species can help managers to mitigate
the impact of such species. Because habitat suitability and the colonization process are key determinants of range expansion,
inferences drawn from invasion patterns should be based on both attributes. To predict the potential habitat and expansion
rate of the invasive tree Bischofia javanica on Hahajima Island, we used simultaneous models of habitat and dispersal to estimate the effect of environment and dispersal
from the source population on the current distribution. We compared the fit and the estimated magnitudes of the environment
and dispersal effects in the simultaneous models with those in habitat suitability and colonization kernel models. The values
of Akaike’s information criterion for the simultaneous models were better than those of the habitat suitability and colonization
kernel models, indicating that the current distribution of Bischofia was determined by both environment and dispersal. The simultaneous models predicted that the potential habitat of Bischofia would be larger than that predicted by the habitat suitability model. The potential habitat distribution and future invasion
predicted by the simultaneous models will contribute to the development of specific landscape-scale management plans to control
this invasive species. 相似文献
993.
994.
Kenji Takizawa Shinichiro Takahashi Norman P. A. Hüner Jun Minagawa 《Photosynthesis research》2009,99(3):195-203
Chlamydomonas raudensis Ettl UWO241, a natural variant of C. raudensis, is deficient in state transitions. Its habitat, the deepest layer of Lake Bonney in Antarctica, features low irradiance,
low temperature, and high salinity. Although psychrophily and low-light acclimation of this green alga has been described,
very little information is available on the effect of salinity. Here, we demonstrate that this psychrophile is halotolerant,
not halophilic, and it shows energy redistribution between photosystem I and II based on energy spillover under low-salt conditions.
Furthermore, we revealed that C. raudensis exhibits higher non-photochemical quenching in comparison with the mesophile Chlamydomonas reinhardtii, when grown with low-salt, which is due to the lower proton conductivity across the thylakoid membrane. Significance of the
C. raudensis UWO241 traits found in the low salinity culture are implicated with their natural habitats, including the high salinity and
extremely stable light environments. 相似文献
995.
996.
Russell W. Jessup 《In vitro cellular & developmental biology. Plant》2009,45(3):282-290
The biofuel industry is rapidly growing because of increasing energy demand and diminishing petroleum reserves on a global
scale. A multitude of biomass resources have been investigated, with high-yielding, perennial feedstocks showing the greatest
potential for utilization as advanced biofuels. Government policy and economic drivers have promoted the development and commercialization
of biofuel feedstocks, conversion technologies, and supply chain logistics. Research and regulations have focused on the environmental
consequences of biofuels, greatly promoting systems that reduce greenhouse gas emissions and life-cycle impacts. Numerous
biofuel refineries using lignocellulosic feedstocks and biomass-based triglycerides are either in production or pre-commercial
development phases. Leading candidate energy crops have been identified, yet require additional efforts to realize their full
potential. Advanced biofuels, complementing conventional biofuels and other renewable energy sources such as wind and solar,
provide the means to substantially displace humanity’s reliance on petroleum-based energy. 相似文献
997.
An hydroponic culture was conducted to investigate the effect of saline stress on the essential oil and fatty acid composition
of Tunisian coriander (Coriandrum sativum L.) roots. Ten days old coriander seedlings were treated during 3 weeks with different NaCl concentrations (0, 25, 50 and
75 mM). Roots volatile components and fatty acids were analyzed. The essential oil yield was 0.06% in the control, on the
basis of dry matter weight, and did not changed at low concentration (25 mM), while it increased significantly with increasing
NaCl concentrations to reach 0.12 and 0.21% at 50 and 75 mM NaCl, respectively. The major volatile component was (E)-2-dodecenal with 52% of total essential oil constituents, followed by decanal, dodecanal, (E)-2-tridecenal and (E)-2-dodecenal. Further, the amount of these compounds was affected differently by the NaCl level. Total fatty acid amount
of coriander roots increased significantly only with 50 and 75 mM NaCl. Three major fatty acids: linoleic (43%), oleic (25.5%)
and palmitic (21.6%) were identified. Linoleic acid amount remains unchanged at 25 mM, while it increased with raising NaCl
concentrations. However, oleic acid amount decreased only at 25 mM and no effect was observed at 50 and 75 mM. Fatty acid
percentages were differently affected by salt. The oleic/linoleic ratio was reduced with raising NaCl concentrations. 相似文献
998.
G. Mulderij B. Mau L. N. de Senerpont Domis A. J. P. Smolders E. Van Donk 《Aquatic Ecology》2009,43(2):305-312
The aquatic macrophyte Stratiotes aloides Linnaeus, which has recently received attention in studies on allelopathy, has been shown to suppress phytoplankton growth.
In the Netherlands, S. aloides often co-occurs with floating filamentous algae. However, filamentous algae are generally absent in close proximity to S. aloides, resulting in gaps in filamentous algae mats. We analyzed whether those gaps may be caused by allelopathic substances excreted
by S. aloides or by nutrient depletion. We studied in a field survey the colonization of natural S. aloides by filamentous algae and determined in situ nutrient concentrations in natural S. aloides stands. To analyze the relative importance of allelopathy and nutrient competition in the interaction between S. aloides and filamentous algae, we carried out field experiments. Introduction of artificial (non-allelopathic) plants in natural
S. aloides stands enabled us to compare the colonization by filamentous algae of both Stratiotes sp. and artificial plants. The filamentous algae were absent in close vicinity to S. aloides. Significantly lower concentrations of ortho-phosphate and potassium were observed close to S. aloides as compared with the filamentous algae. In the field experiments the artificial plants were rapidly colonized by filamentous
algae, mainly Cladophera Kützing and Spirogyra Link, while all natural plants remained free of such algae. Additionally, most nutrient concentrations did not significantly
differ in the proximity of artificial or natural stands of S. aloides. The concentrations of the major growth-limiting nutrients, phosphate and nitrate, were significantly higher and nonlimiting
in natural Stratiotes stands. Our main conclusion is that, although allelopathic interactions between S. aloides and filamentous algae do occur under natural conditions, nutrient competition between the two can also be an important factor. 相似文献
999.
Haidong Ding Aying Zhang Jinxiang Wang Rui Lu Hong Zhang Jianhua Zhang Mingyi Jiang 《Planta》2009,230(2):239-251
Mitogen-activated protein kinase (MAPK) cascades have been shown to be important components in abscisic acid (ABA) signal
transduction pathway. In this study, a 46 kDa MAPK (p46MAPK) induced by ABA was partially purified from maize (Zea mays) by Q-Sepharose FF, Phenyl-Sepharose FF, Resource Q, Mono QTM 5/50 GL, poly-l-lysine-agarose, and Superdex 75 prep-grade columns, and was identified as ZmMAPK5 (gi|4239889) by the matrix-assisted laser
desorption/ionization time-of-flight/time-of-flight (MALDI-TOF/TOF) mass spectrometry. Furthermore, the kinase showed optimal
activity at pH 8.0, 30°C, and 10 mM MgCl2; the K
m
for myelin basic protein (MBP) substrate and ATP were 0.13 μg μl−1 and 62 μM, respectively. MBP was the preferred substrate, of which the threonine residue was phosphorylated. Finally, the
kinase was found to respond to diverse extracelluar stimuli. These results enable us to further reveal the function of the
ZmMAPK5 in ABA signaling.
The authors Haidong Ding and Aying Zhang contributed equally to the work. 相似文献
1000.