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This paper attempts to employ water footprint approach to analysis the real use situation of water resource in Jiangsu Province,and established C2R and BC2models of data envelopment analysis(DEA) from the input-output perspective,which incorporates agricultural water,industrial water,domestic water,total COD discharge,fixed asset investment and labor as input indicators,and GDP and food production as output indicators to evaluate the water resources use efficiency of Jiangsu Province from the year 2000 to 2010.The results have shown that the water footprint of Jiangsu is 778.28 m3,indicating a slowly rising trend.In addition,the agricultural water,industrial water and the virtual water trade are major parts of water resource use in Jiangsu Province.The effective year of DEA accounts for 64% during the 11 years,and the redundant inputas well as the insufficient output is zero value,which means that the input-output has achieved the optimal state.While the redundant input in the invalid years of DEA have shown the extra pollution and resources allocation is unreasonable,which can be theoretically resolved to arrive at the optimal equilibrium point through the analysis of the DEA projection.

最新发布的1981-2012年的AVHRR GIMMS NDVI3g数据为了解区域植被的近期变化状况提供了数据基础。深入理解该版本与老版本GIMMS NDVIg（1981-2006年）之间的关系，对于使用新数据时充分利用已有老版本的研究结果具有重要意义。以我国西北干旱区的典型区域——新疆为例，研究了两个数据集在反映生长季、春季、夏季和秋季植被现状，植被变化趋势及其对气候变化响应方面的异同。研究结果表明：两个数据集在描述植被活动空间分布、变化趋势及其与气候的相关性方面大体相似，但在数值、动态变化率及其对气候变化响应强度等方面存在的差异也不容忽略。NDVI3g数据生长季和各季节NDVI数值多大于NDVIg，尤其是在夏季和在植被覆盖较好的区域。区域尺度，NDVI3g所反映的植被变化趋势更为平稳，尤其是在夏季和较长的时段，这可能与像元尺度NDVI3g显著增加范围小于NDVIg，而显著减少范围多于NDVIg有关。两个数据集对气温、降水量、潜在蒸散发和湿润指数的响应具有大体一致的空间格局，但对气候因子变化的敏感性存在差异，哪一个数据集更为灵敏依赖于不同的气候因子和时段。一般规律是NDVI3g与热量因子显著正相关的区域小于NDVIg，而与水分因子显著正相关的区域则大于NDVIg。利用长期的生态数据集，尽快理清两个数据集在表征植被变化之间的异同并建立两者的转换关系，对于合理开展植被变化、碳平衡、生态系统服务功能评估等广泛利用NDVI数据的相关研究十分重要。

The distribution of photosynthesis within the canopy determines the productivity and quality in a fruit orchard.A model of photosynthesis was developed to simulate the three-dimensional(3-D) distribution of leaf net photosynthetic rate(Pn),stomatal conductance(Gs) and light use efficiency(LUE) in apple canopy.The experiment was conducted in a 'Fuji' apple(Malus domestica Borkh.cv.'Fuji') orchard during the 2007—2009 growing seasons.The orchard is on the farm in Guojia Town(35° 11′ N,105° 21′ E,altitude 1530 m) of Gansu Province.The planting spacing was 3 m × 4 m,and each tree was trained as an spindle system.The model was developed on the basis of 3-D distribution of canopy radiation and leaf area determined by direct measurement.Foliage photosynthetic capacity at different canopy positions was described by an experiential equation,and the leaf photosynthesis model is based on the mechanistic understanding of C3 photosynthesis.The parameters of the leaf photosynthesis model,that is,the maximum carboxylation rate,potential rate of electron transport,the rate of triose phosphate utilisation and their CO2 and temperature dependence,were determined using gas-exchange data of fully expanded,mature leaves. In the whole canopy,about 64.51% of the leaves were 1.0—2.0 m from the canopy,35.49% were at other distances from the canopy.No obvious difference in leaf area distribution was seen in the north-south orientation,and a basin foliage distribution was concentrated around the trunk.In the vertical section,the relative radiation decreased with increasing canopy depth.The rapid depression of the relative radiation was concentrated in the middle of the canopy where the leaf area density was highest.And more than 36% of the relative radiation was on the sides compared to near the trunk.The simulation showed that the 3-D distribution of Pn was similar to that of the relative radiation.When canopy height decreased from upper to bottom canopy,the relative radiation decreased by 89% from 71.18% to 8.05% and Pn decreased by 87% from 15.05 μmol · m-2 · s-1 to 1.92 μmol · m-2 · s-1(PAR=1500 μmol · m-2 · s-1).A flat step in the top canopy of the 3-D Pn distribution was observed,which decreased rapidly with the decreasing radiation.However,the 3-D distribution of the total photosynthetic rate in a unit cell appeared to mainly track the distribution of the leaf area and was partly correlated with the Pn.The 3-D distribution of Gs patterns was similar to that of Pn.And the distribution of LUE was reverse to Pn,which was more in bottom layer and less in upper layer.Satisfactory correspondence was achieved between measured and simulated values of Pn and Gs in different position of apple canopy,which was showed that the coupled model has the ability to predict Pn in a 3-D apple canopy.The main aim of fruit tree pruning is to remove useless shoots and leaves,and identification of these parts can be conveniently determined in a 3-D canopy plot.Overall,the coupled model performed well in predicting Pn for different leaf area distribution patterns.The 3-D distribution of Pn,Gs and LUE were determined by direct measurement of the 3-D distribution of radiation,leaf area and C3 photosynthesis models in an apple orchard.The parameters of the model were maintained as simply as possible to facilitate their wide use in canopy photosynthesis simulations,especially for studying the effects of shape and pruning in fruit trees.