Analysis of arable land loss and its impact on rural sustainability in Southern Jiangsu Province of China

Rapid urbanization and industrialization in southern Jiangsu Province have consumed a huge amount of arable land. Through comparative analysis of land cover maps derived from TM images in 1990, 2000 and 2006, we identified the trend of arable land loss. It is found that most arable land is lost to urbanization and rural settlements development. Urban settlements, rural settlements, and industrial park-mine-transport land increased, respectively, by 87 997 ha (174.65%), 81 041 ha (104.52%), and 12 692 ha (397.99%) from 1990 to 2006. Most of the source (e.g., change from) land covers are rice paddy fields and dryland. These two covers contributed to newly urbanized areas by 37.12% and 73.52% during 1990-2000, and 46.39% and 38.86% during 2000-2006. However, the loss of arable land is weakly correlated with ecological service value, per capita net income of farmers, but positively with grain yield for some counties. Most areas in the study site have a low arable land depletion rate and a high potential for sustainable development. More attention should be directed at those counties that have a high depletion rate but a low potential for sustainable development. Rural settlements should be controlled and rationalized through legislative measures to achieve harmonious development between urban and rural areas, and sustainable development for rural areas with a minimal impact on the ecoenvironment. (C) 2009 Elsevier Ltd. All rights reserved.

Model analysis of dissolved inorganic phosphorus exports from the Yangtze river to the estuary

In this paper, we estimate the inputs of phosphorus (P) to the Yangtze River Basin and exports of dissolved inorganic phosphorus (DIP) from the river to the estuary for the period 1970-2003, by using the global NEWS-DIP model. Modeled DIP yields range from 2.5 kg P km(-2) yr(-1) in 1970 to 4.6 kg P km(-2) yr(-1) in 1985, and then dramatically increase to 14.1 kg P km(-2) yr(-1) in 2003. No significant difference between the modeled and measured values at the level of P = 0.05 is observed. The study also demonstrates variable source contributions of P to the modeled DIP during the period 1970-2003. Point sewage P input accounted for approximately 100% in the period 1970-1985 and substantially decreased to 24.8% in 2003. Chemical fertilizer contributed 25.4% of DIP yields in 1986 and increased continuously to 50.3% in 2003, while a stable trend in manure P contribution averaging 22.9% of DIP yields was shown in the same period. The study concludes that P inputs to the Yangtze River Basin and the river DIP export to the estuary have substantially increased during the study period consequence to human pressure.

Microstructure analysis of nylon 66 by WAXD and SAXS

The analysis of the small angle X-ray scattering (SAXS) data was based upon particle characteristic function, one-dimensional electron-density correlation function and particle distribution function. The microstructure of nylon 66 with different degrees of crystallinity was studied by means of X-ray scattering method. The radius of gyration R-g, the Porod radius R-p, the thickness of crystalline region L-c the thickness of non-crystalline region L-n, the thickness of interphase region d(tr), the long period L, the semiaxises of particles (a, a, b), the distribution of the particle sizes and the scattering invariant were calculated. The results indicate that there was a significant interphase region between the crystalline region and the non-crystalline region. and its content (W-t,W-x) should not be neglected in comparison with that of crystalline region W-c,W-x. The morphology of nylon 66 prepared by isothermal crystallization at a high temperature was mainly a lamellar structure, while the spherical crystals dominated in the quenched sample. The size of the particles in the quenched sample was smaller than that of those in the isothermally crystallized sample. and the distribution of the particle sizes in the isothermally crystallized sample was wider.

FLOW-INJECTION ANALYSIS OF MYOGLOBIN AND HEMOGLOBIN AT TOLUIDINE BLUE CHEMICALLY MODIFIED ELECTRODE

Electrodeposition of the phenothiazine mediator titrant toluidine blue onto a glassy carbon substrate at an appropriate potential was used to construct a toluidine blue chemically modified electrode (CME) exhibiting electrocatalytic reduction for myoglobin and hemoglobin. The CME catalyzed the hemoprotein electroreduction at the reduction potential of the mediator molecule. When the CME as used as a detector for flow injection analysis at a constant applied potential of -0.30 V vs. a saturated calomel electrode, it gave detection limits of 20 and 50 ng (1.2 and 0.78 pmol) injected myoglobin and hemoglobin, respectively, with a dynamic linear concentration range over 2 orders of magnitude. After a brief equilibration period, the CME retained nearly 90% of its initial myoglobin response over 8 hours of continuous exposure to the flow-through system.

Vast laminated diatom mat deposits from the west low-latitude Pacific Ocean in the last glacial period

Diatoms are one of the predominant contributors to global carbon fixation by accounting for over 40% of total oceanic primary production and dominate export production. They play a significant role in marine biogeochemistry cycle. The diatom mat deposits are results of vast diatoms bloom. By analysis of diatom mats in 136 degrees 00'-140 degrees 00'E, 15 degrees 00'-21 degrees 00'N, Eastern Philippines Sea, we identified the species of the diatoms as giant Ethmodiscus rex (Wallich) Hendey. AMS C-14 dating shows that the sediments rich in diatom mats occurred during 16000-28600 a B.P., which means the bloom mainly occurred during the last glacial period, while there are no diatom mat deposits in other layers. Preliminary analysis indicates that Antarctic Intermediate Water (AAIW) expanded northward and brought silicate-rich water into the area, namely, silicon leakage processes caused the bloom of diatoms. In addition, the increase of iron input is one of the main reasons for the diatom bloom.

Millennial-scale paleoceanography in Okinawa Trough during Late Quaternary period

Based on the analyses of foraminifer and accelerator mass spectrometer radiocarbon dating in DGKS9603 core from mid-Okinawa Trough close to bottom, oscillation curve, which expressed the relation between the surface water temperature and the depth, has been obtained by using foraminifer analysis and calculation of FP-12E transfer function. The whole core indicated seven cold phases and eight warm phases. Obvious expression of low temperature event during Middle and Late Holocene, YD,H1,H2,H3 and H4 events, as well as the short cold phase during the middle last glacial period, implied that short shifts since 50 kaBP would have been global significance. Sedimentation rate during cold phases is usually faster than that in warm stages, with the lowest rate in Holocene, which may be connected with rising sea level and principal axial of Kuroshio Current moving to west. Volcanic activities highly developed in Okinawa Trough during the Quaternary period, thus abundant volcanic glass and pumice were well preserved.

An analysis of the recent severe storm surge disaster events in China

The economic loss caused by the storm surge disasters is much higher than that caused by any other marine disaster in China, the loss from the severe storm surge disaster being the highest. Statistics show that there were 62 typhoon landings over the east-southeast coast of China since 1990, three of which, occurring in 1992, 1994 and 1997, respectively, caused the most severe damage. The direct economic losses due to these events are 9.3, 17.0 and 30 billion yuan (RMB, or about 1.7, 2.6 and 3.8 billion USD, respectively), which is much greater than the loss of 5.5 billion yuan (RMB) on an average every year during the 1989-1991 period. This paper makes a comparative analysis of the damage caused by the three events and presents an overview of progress of precautions against storm surge disaster in China. The suggested counter measures to mitigate the loss from the severe storm surge disasters in China is as follows: (1) Raise the whole society awareness of precaution against severe storm surge disaster; (2) Work out a new plan for building sea walls; (3) Improve and perfect the available warning and disaster relief command system; (4) Develop the insurance service in order to promptly mitigate the loss caused by severe storm surge disaster event.

Analysis of the sea-level variability along the Chinese coast and estimation of the impact of a CO2-perturbed atmospheric circulation

The relationship between monthly sea-level data measured at stations located along the Chinese coast and concurrent large-scale atmospheric forcing in the period 1960-1990 is examined. It is found that sea-level varies quite coherently along the whole coast, despite the geographical extension of the station set. A canonical correlation analysis between sea-level and sea-level pressure (SLP) indicates that a great part of the sea-level variability can be explained by the action of the wind stress on the ocean surface. The relationship between sea-level and sea-level pressure is analyzed separately for the summer and winter half-years. In winter, one factor affecting sea-level variability at all stations is the SLP contrast between the continent and the Pacific Ocean, hence the intensity of the winter Monsoon circulation. Another factor that affects coherently all stations is the intensity of the zonal circulation at mid-latitudes. In the summer half year, on the other hand, the influence of SLP on sea-level is spatially less coherent: the stations in the Yellow Sea are affected by a more localized circulation anomaly pattern, whereas the rest of the stations is more directly connected to the intensity of the zonal circulation. Based on this analysis, statistical models (different for summer and winter) to hindcast coastal sealevel anomalies from the large-scale SLP field are formulated. These models have been tested by fitting their internal parameters in a test period and reproducing reasonably the sea-level evolution in an independent period. These statistical models are also used to estimate the contribution of the changes of the atmospheric circulation on sea-level along the Chinese coast in an altered climate. For this purpose the ouput of 150 year-long experiment with the coupled ocean-atmosphere model ECHAM1-LSG has been analyzed, in which the atmospheric concentration of greenhouse gases was continuously increased from 1940 until 2090, according to the Scenario A projection of the Intergovermental Panel on Climate Change. In this experiment the meridional (zonal) circulation relevant for sea-level tends to become weaker (stronger) in the winter half year and stronger (weaker) in summer. The estimated contribution of this atmospheric circulation changes to coastal sea-level is of the order of a few centimeters at the end of the integration, being in winter negative in the Yellow Sea and positive in the China Sea with opposite signs in the summer half-year.

Analysis of high wheat yields in Northwest China

Grain yields of over 14 Mg ha(-1) were reported in 1978 for spring wheat (Triticum aestivum L.) grown in Northwest China. Understanding the circumstances under which this record yield was achieved may be useful in defining the key factors that lead to high grain yields and in determining the limits to wheat yield. A relatively simple, mechanistic model was used in an effort to simulate the record yield. The model was used as a framework in which various crop traits could be adjusted to match the observed crop growth. The weather that was characterized by cool temperatures and high levels of solar radiation, proved to be especially important in allowing a full-season crop to achieve record yields. Variables defining plant development in the model also had to be set to describe the high yielding cultivar grown in China. Leaf development was defined by the length of a phyllochron, which was set equal to 78 TU (thermal units, base temperature equal to 0 degrees C) based on independent data. The description of grain fill had to be defined to match simulation results with the observations. Two variables, length of the grain-fill period and the grain growth rate, were set in response to the unique traits of this cultivar and the low temperatures during grain development. These simulations led to important suggestions for examining the interaction between cool temperature regimes and developmental traits of wheat cultivars. (C) 1997 Published by Elsevier Science Ltd.