Increasing atmospheric greenhouse gas concentration is expected to induce significant climate change over the next century, but the impacts on society remain highly uncertain. This paper aimed to assess the potential impacts of climate change on rice crop ( Oryza sativa L.) production in the middle and lower reaches of the Yangtze River, where is one of the most important food production regions in China. Data taken from the PRECIS regional climate model were used as the baseline (1961–1990) and future (2021–2050) periods under IPCC SRES A2 and B2 scenario conditions, and were used as input of the rice model ORYZA2000. Simulations were performed with and without considering the enhanced CO 2 -fertilization effects to evaluate the response of rice crop to raised temperature and CO 2 concentration, respectively. The results indicated that the rice growth duration would be shortened and yield would be declined significantly with raising temperature future when CO 2 -fertilization effects was not considered. The rice growth duration would be shortened by 4.5 d and yield would be reduced by 15.2% under A2 scenario in 2021–2050 periods compared with the baseline weather while they would be 3.4 d shortened and 15% reduced respectively under B2 scenario in the same period. The areas where rice yield reduced more than 20% concentrated on most regions of Anhui, Hubei and Hunan provinces. The significance of the enhanced CO 2 -fertilization effect to rice crop was found under the simulated future elevated CO 2 concentrations (2021-2050) for both A2 and B2 scenarios. But it was still not enough to offset the negative effects of warming for single crop rice and early rice, except for the late rice that the contribution of CO 2 -fertilization effect on rice yield was greater. With considering CO 2 -fertilization effect, the rice yields declined by 5.1% and 5.8% under A2 and B2 scenarios, respectively. The areas with a serious yield reduction decreased and the average yield reduction were lessened remarkably. Meanwhile, the areas with an increase in rice yields were founded in some parts of Jiangxi and Zhejiang provinces, although the yield increase might be less than 10%. In addition, the yield stability, defined as the ratio of standard deviation to average yield at each grid across each province, would be increased in 2021–2050 periods when CO 2 -fertilization effect was considered, indicating that the CO 2 -fertilization effect may reduce the future yield variability. However, there were still many uncertainties in this study. The possible impact of water stress under future climate was not considered, due to the automatic irrigation pattern selected. The soil parameters used as input to the ORYZA2000 might increase the uncertainties for assessing the impacts of climate change on rice yield. Finally, the overall results were compared with those in other studies, in which CERES-Rice was employed and a good agreement was obtained, indicating that the rice model ORYZA2000 can be well applied in assessing the impact of climate change on rice crop in China.

选择长江中下游平原作为研究区域，按照政府间气候变化专业委员会(IPCC)排放情景特别报告(SRES)中的A2和B2方案，将基于区域气候模式PRECIS构建的气候变化情景文件与水稻生长模型ORYZA2000结合，模拟基准时段(1961—1990)气候(Baseline)和2021—2050时段A2、B2情景下的水稻产量，分析未来气候变化对长江中下游水稻产量的影响。构建两种影响评估方法，重点分析增温和大气CO 2 肥效作用对水稻产量的影响。结果表明，不考虑CO 2 肥效作用时，随着温度升高，水稻生育期缩短，产量下降。A2情景下水稻生育期平均缩短4.5 d，产量减少15.2%；B2情景下平均缩短3.4 d，产量减少15%。其中，减产达到20%以上的区域集中在安徽中南部、湖北东南部和湖南东部地区。当考虑CO 2 肥效作用后，A2情景下水稻平均产量减少5.1%，B2情景平均减少5.8%。减产区域缩小且幅度降低，江西和浙江部分地区则呈现一定程度增产，但增幅 2 肥效作用一定程度上可提高水稻产量，使晚稻在增温的不利影响下仍呈现不同程度的增产态势，但对单季稻和早稻的增产贡献仍不足以抵消升温的负面影响。另外，大气CO 2 肥效作用可有利于提高未来气候变化下水稻的稳产性。

基于西北典型半干旱区马铃薯定位观测试验，结合气候要素平行观测资料，研究了半干旱区马铃薯产量对气候变化的响应。结果表明，1957—2015年间（59 a），西北半干旱区在气温显著上升，气温和降水量气候倾向率分别为0.238℃/10 a、-10.517 mm/10 a。马铃薯产量与苗期（6月）呈显著负相关（P<0.01），与块茎膨大期（8月）气温也呈负相关（P<0.10），6—8月气温每升高1℃，马铃薯产量下降4391.39~6798.46 kg·hm-2。产量与生育期≥0℃积温呈显著负相关（P<0.05），适宜≥0℃积温阈值为2307.4℃。产量与苗期降水量呈正相关（P<0.10），适宜降水量阈值为47.8 mm。产量与9月中旬日照时数呈显著正相关（P<0.01）。马铃薯生育期干燥指数与产量呈显著负相关（P<0.05），适宜阈值为1.88。研究还发现气温变化对马铃薯产量影响的敏感期在出苗至分枝期，而水分影响马铃薯产量敏感期分别在分枝到开花期和块茎膨大期，同时，块茎膨大期也是日照变化影响产量的敏感期。因此，气候变暖对西北半干旱地区马铃薯的生产形成了负面影响。

Based on the data of climate and observations data at seven agro meteorological stations of Jiangsu province during 1981 to 2009,authors investigated the effects of climate change on rice yields in Jiangsu province by the basic equation of mean temperature and precipitation influence to the rice yield and defining the contribution rate of the mean temperature and precipitation trend on rice yield trend.The results showed that the mean temperature and minimum temperature had an increasing trend during the whole rice growth season in Jiangsu province,but maximum temperature in southern and northern Jiangsu had a different trend for the last 30 years,which had an increasing trend in southern part and a decreasing trend in northern part from flowering to maturing.The relationship between temperature (including mean temperature,minimum temperature and maximum temperature)and rice production was positive,and the warming trend increased rice yield by about 1.2%,and the contribution rate to yield trend accounted for 30.0% during 1981 to 2009.Trend in precipitation was not obvious,increased slightly in the northern part while decreased slightly in the southern part.The relationship between precipitation and rice yields was not obvious either,so the effects of the precipitation trends on rice yields were small.In general,rice productivity in Jiangsu province benefited from climate change during the last 30 years.

利用江苏省1981-2009年7个农业气象站点的气象和水稻物候、产量资料，从平均气温和降水量对水稻产量影响的基本方程入手，定义了平均气温和降水量变化趋势对水稻产量趋势的贡献率，揭示江苏省近30a气候变化趋势对水稻产量的影响。结果表明，近30a来，江苏省水稻全生育期平均气温和最低气温呈上升趋势，最高气温的变化在苏南和苏北地区差异较大，尤其在开花－成熟阶段，苏南地区呈上升趋势，而苏北地区则呈相反变化趋势。气温（包括平均气温、最低气温和最高气温）与水稻产量呈正相关，1981-2009年平均气温升高对江苏省水稻产量影响的平均值约为1.2%，对产量趋势的贡献率约为30.0%。降水量的变化趋势不明显，降水量与水稻产量的相关性亦不显著，说明在研究区内降水量的变化对水稻产量的影响较小。总体上，江苏省近30a气候变化有利于水稻生产。

像桃、李、杏、板栗、银杏、枣子、山核桃等常见的果树在生长发育过程中,常因管理经营粗放、树体营养不足、授粉不良、病虫害严重等因素造成落花落果,影响果树的坐果率,从而降低果树的产量和品质.根据多年的经验和对比试验,现推荐8种行之有效的方法,提高果树的坐果率.

摘　要： 2012-2014 年，在浙江省临安市山核桃（Carya cathayensis）林地开展了微肥定位试验。对山核桃叶片硼（B）、锌（Zn）和铜（Cu）的进行动态测定，分析B、Zn和Cu肥对山核桃叶片养分变化的影响、与山核桃花粉活力和山核桃产量的关系。结果表明：B、Zn、Cu 微肥配施都能有效提高山核桃叶片中B、Zn 含量，叶片B、Zn含量增幅分别为5.3% ~ 46.2%和2.3%~44.5%，对叶片Cu 的含量影响没有明显规律；从生长初期（4月）、灌浆期（7月）至成熟期（9月），山核桃叶片B、Zn 和Cu含量呈逐渐下降趋势，下降幅度为Cu>Zn>B；硼锌配施显著提高山核桃花粉活力，铜肥对花粉活力无影响；B、Zn同时施用能显著提高山核桃产量，第2年的效果更为明显。试验证明B和Zn对山核桃叶片、花粉活力和山核桃产量的影响均较Cu大，建议在施肥管理中，注重硼肥和锌肥的施用。