Integrated use of GIS, remote sensing and multi-criteria decision analysis to assess ecological land suitability in multi-functional forestry

The Zagros forests are a treasure of valuable oak forests, but they have been severely degraded from long-term misuse. Geographic information systems （GIS） and multi-criteria decision analysis （MCDA） have been increasingly used to improve the management of vulnerable ecosystems to prevent further degradation and increase the sustainability of land use. This study presents a methodology to assess land suitability using remote sensing （RS） to obtain wall-to-wall data for the calculations, GIS to analyze the data, and MCDA to rank alternative land uses. The criteria and subcriteria affecting the suitability of land for different uses were identified and weighted using an analytic hierarchy process. Variables used as subcriteria were assessed using satellite data and other sources of information such as existing maps and field surveys. Numerical values for the subcriteria were classified, and each class was given a priority rating according to expert judgments. Based on the ratings and weights of the subcriteria, a priority map was created for each land use using the weighted linear combination method. The priority maps for different land uses were overlaid to obtain a preliminary land use map, which often indicated several simultaneous land uses for the same location. The preliminary map was further edited by removing unrealistic, mutually exclusive land-use combinations. The study tested and demonstrated the potential of integrating RS, G1S and MCDA techniques for solving complicated land allocation problems in forested regions using a scientifically sound and practical approach for efficient and sustainable allocation of forestland for different uses.

Review on simulation of land-surface processes on the Tibetan Plateau

The Tibetan Plateau(TP) has powerful dynamics and thermal effects, which makes the interaction between its land and atmosphere significantly affect climate and environment in the regional or global area. By retrospecting the latest research progress in the simulation of land-surface processes(LSPs) over the past 20 years, this study discusses both the simulation ability of land-surface models(LSMs) and the modification of parameterization schemes from two perspectives, the models' applicability and improved parameterization schemes. Our review suggests that different LSMs can well capture the spatiotemporal variations of the physical quantities of LSPs; but none of them can be fully applied to the plateau, meaning that all need to be revised according to the characteristics specific to the TP. Avoiding the unstable iterative computation and determining the freeze-thaw critical temperature according to the thermodynamic equilibrium equation, the unreasonable freeze-thaw parameterization scheme can be improved. Due to the complex underlying surface of the TP, no parameterization scheme of roughness length can well simulate the various characteristics of the turbulent flux over the TP at different temporal scales. The uniform soil thermodynamic and hydraulic parameterization scheme is unreasonable when it is applied to the plateau, as a result of the strong soil heterogeneity. There is little research on the snow-cover process so far,and the improved scheme has no advantage over the original one due to the lack of some related physical processes. The constant interaction among subprocesses of LSPs makes the improvement of a multiparameterization scheme yield better simulation results. According to the review of existing research, adding high-quality observation stations, developing a parameterization scheme suitable for the special LSPs of the TP, and adjusting the model structures can be helpful to the simulation of LSPs on the TP.

Spatial-temporal variation of the land surface temperature field and present-day tectonic activity

This study attempts to acquire information on tectonic activity in western China from land surface temperature （LST） field data. On the basis of the established relationship between heat and strain, we analyzed the LSTdistribution in western China using the satellite data product MODIS/Terra. Our results show that： 1. There are departures from annual changes of LSTin some areas, and that these changes are associated with the activity of some active tectonic zones. 2. When annual-change background values caused by climate factors are removed, the long-period component （LSTLow） of temperature residual （AT） of the LSTis able to serve as an indicator for tectonic activity. We have found that a major earthquake can produce different effects on the/ST fields of surrounding areas. These effects are characterized by both rises and drops in temperature. For example, there was a noteworthy temperature decline associated with the Sumatran M9 earthquake of 2004 in the Bayan Har-Songpan block of central Tibetan Plateau. 3. On the other hand, the LST field of a single area may respond differently to major shocks occurring in different areas in the regions surrounding China. For instance, the Kun- lun M 8.1 event made the LSTon the Longmen Mountains fault zone increase, whereas the Zaisan Lake M 7.9 quake of 2003, and the Sumatran M 9 event of 2004, caused decreases in the same area＇s LST. 4. The variations of land surface temperature （LST） over time are different in different tectonic areas. These phenomena may provide clues for the study of tectonic deformation processes. On the basis of these phenomena, we use a combi- nation of temperature data obtained at varied depths, regional seismicity and strain results obtained with GPS measurements, to test the information related to tectonic activity derived from variations of the LST field, and discuss its implications to the creation of models of regional tectonic deformation.

国外土地金融制度对我国农地制度改革的启示

我国农地制度中存在产权关系不明、农地流转市场发育不良、农地缺乏长期投入等问题．借鉴国外上地金融制度的成功经验，对建立我国土地金融制度、演化和促进我国农地制度改革有着重要的启示．

Spatially precise reconstruction of cropland areas in Heilongjiang Province, northeast China during 1900-1910

It is necessary to reconstruct past changes in land use and land cover to under- stand the historical effects of humans on climate and the local environment. We collected information from historical documents on the cropland area at the county level for Heilongji- ang Province, northeast China during 1900-1910. The original records from different histori- cal documents were calibrated with each other. We then defined an agricultural suitability index quantified by the distance from settlements, the slope and complexity of the topography, and the distance from rivers. Following the order of the agricultural suitability index from high to low values, the documented areas of cropland at the county level were then allocated into 1 km x 1 km cells. The area of cropland in 2009 was then retrieved from Landsat ETM＋ images and compared with the areas of cropland during 1900-1910 to determine the human-induced changes in land use and land cover. In this period, the total area of cropland was about 25,397 km2 and this mainly occurred in the mid-southern part of Heilongjiang, in particular the six counties of Hailun, Bayan, Wuchang, Hulan, Shuangcheng and Wangkui. In 2009, the total area of cropland had increased to about 163,808 km2 and had spread over the south- western part to the central and northeastern parts of Heilongjiang. The area of cropland had therefore increased by about 138,411 km2 during the 20th century. The proportion of land used as cropland increased from about 5.6% during 1900-1910 to about 36.2% in 2009, indicating that about 30.6% of the natural land surface in Heilongjiang was replaced by cropland. A total of about 44% （60,962 km2） of the cropland was converted from forest, mainly on the western edge and in the northeastern part of the present-day agricultural area. These areas of cropland reconstructed from historical records for the period 1900-1910 could be used as a basic data set to study the effects of agricultural development on climate and the local environment.

Significance of the carbon sink produced by H_2O–carbonate–CO_2–aquatic phototroph interaction on land

One of the most important questions in the science of global change is how to balance the atmospheric CO2 budget. There is a large terrestrial missing carbon sink amounting to about one billion tonnes of carbon per annum. The locations, magnitudes, variations, and mechanisms responsible for this terrestrial missing carbon sink are uncertain and the focus of much continuing debate. Although the positive feedback between global change and silicate chemical weathering is used in geochemical models of atmospheric CO2, this feedback is believed to operate over a long timescale and is therefore generally left out of the current discussion of human impact upon the carbon budget. Here, we show, by synthesizing recent findings in rock weathering research and studies into biological carbon pump effects in surface aquatic ecosystems, that the carbon sink produced by carbonate weathering based on the H2O- carbonate-CO2-aquatic phototroph interaction on land not only totals half a billion tonnes per annum, but also displays a significant increasing trend under the influence of global warming and land use change; thus, it needs to be included in the global carbon budget.

Psalm 137 According to Zhang Xiaofeng： The Walling Wall in Post-1949 Taiwan Literary History

The aim of this essay is to analyze the first story by Zhang Xiaofeng, Taiwan writer, playwright, known in the mainland of China mainly as an excellent essayist. The Wailing Wall （Kuqiang） was written in 1968 in the atmosphere of the Six Days War in Israel, the atrocities during the first years of the Cultural Revolution in the mainland of China, and war in Vietnam, Wailing Wall is a poetic symbol of sadness and suffering mostly of the innocent people. For the author of the story it is reminiscent of the biblical Psalm 137 depicting the moods of the Hebrews in the Babylonian Captivity after 586 B.C. and the situation of her compatriots who were forced to leave their old homes in the Mainland before Oct. 1, 1949. Zhang Xiaofeng is a Christian author regarding love as the cornerstone of inter-human relations. She believes in love of God for all human beings and in the universal love. The short story consisting of one woman and her relations with two brothers between October 1949 and June 1967, against the background what happened in the world around them, and in their vicinity, brought her an unpleasant cognition： The true love is hardly possible where the human beings should live between, or behind the walls, where hate is prevailing.

Optimizing photosynthetic and respiratory parameters based on the seasonal variation pattern in regional net ecosystem productivity obtained from atmospheric inversion

In this study, we explore the feasibility of optimizing ecosystem photosynthetic and respiratory parameters from the seasonal variation of the net carbon flux. An optimization scheme is proposed to estimate two key parameters （V2max and Q10） by exploiting the seasonal variation in the net ecosystem carbon flux retrieved by an atmospheric inversion system. This scheme is implemented to estimate V25max and Q10 of the boreal ecosystem productivity simulator （BEPS） to improve its NEP simulation in the boreal North American region. Then, in situ NEE observations at six eddy covariance sites are used to evaluate the NEE simulations from BEPS with initial and optimized parameters. The results show that the performance of the optimized BEPS is superior to that of the BEPS with the default parameter values. These results implicate that it is possible to optimize ecosystem model parameters by different sensitivities of V25max and Q10 during growing and non-growing seasons through atmospheric inversion or data assimilation techniques.