中国农业气象灾害对作物产量的影响

根据中国主要作物产量、受灾面积和气象条件等相关资料，详细分析了全国主要农业气象灾害的分布地区、季节特点及变化特征。结果表明：干旱、洪涝和冷冻害是影响作物产量的主要气象灾害，而各种灾害均有明显增加的趋势。旱灾是最严重的灾害，受灾面积是洪涝面积的2．3倍。分析了全国主要农业气象灾害对作物产量的严重影响，玉米和大豆产区主要是旱灾，早稻和晚稻产区主要是冷害和洪灾，一季稻和棉花产区主要是洪涝和旱灾，冬小麦和油菜产区的严重减产主要受冻害影响。     

农作物病虫害气象环境成因研究进展

简要概述了近年来农作物病虫害气象环境成因研究方面的最新进展,包括农作物病虫害发生流行的气候背景指示及其影响机制、与气象条件的关系和气候变化对病虫害发生流行的可能影响等.结果表明:海温、厄尔尼诺事件、大气环流等大尺度因子对病虫害的发生流行具有明显的前兆性指示;温度、湿度、降雨、风、光照等气象要素,对促进或抑制某种病虫害的发生、发展、流行及其危害程度都可能产生显著的影响;气候变化可能造成病虫害危害的地理范围扩大,程度加剧.     

Predators choosing between patches with standing crop: the influence of switching rules and input types

Where prey arriving in a patch are not consumed immediately, they will accumulate. Predators are then presented with a prey density or standing crop that increases through further input, and decreases through the consumption by predators. Firstly, I show that the switching rule of predators has a significant influence on the expected predator equilibrium distribution in such a dynamic system. Three rules are compared; for all rules, analytical solutions are calculated (where possible). To test their plausibility for natural situations, predator distributions are simulated given the assumption that each predator obtains individual patch profitability estimates by using a common learning rule. As long as prey arrive in the patches in constant numbers per time unit, the first rule leads to input matching because predators stop switching when consumption in the two patches is equal. The other two rules, where predators continue to sample both patches even in the equilibrium state, lead to predator distributions where the more profitable patch is underused. The final equilibrium depends on the exact assumptions of the switching rule; however, it is independent of interference. But if the input delivered into a patch is a function of the current prey standing crop (for example in a reproducing prey population), predator and prey distributions will not reach an equilibrium in most cases: either standing crops increase indefinitely, or they approach zero, with all predators concentrating on the better patch. Only a small number of parameter sets show intermediate crops that are reasonably stable. With this input type, only up to 54% of the simulations reach the expected distribution. In a system with competition for dynamic standing crop, it is therefore essential to know the type of input and the switching-rule used by predators to be able to predict equilibrium predator distributions. Received: 17 March 1995/Accepted after revision: 5 November 1995     

厄尔尼诺灾害的地球动力学解释以及与地质科学的联系

本文从地质力学的理论基础出发,详细地叙述了对厄尔尼诺这一大尺度气象灾害的机制所作的探讨。指出对于地球上任何大尺度的自然现象进行分析、探讨、研究时,都不应忽视地球自转的作用和影响。本文还将海气相互作用与构造体系进行了联系并对全世界地质学与环境生态学界普遍关注的全球海平面变化问题表述了自己的见解。     

VALUING IRRIGATION WATER: A SIMULATION/MATHEMATICAL PROGRAMMING APPROACH1

ABSTRACT: A two-stage simulation/mathematical programming model was developed to derive irrigation water values that reflect efficient response to reduced water supplies. The failure of many previous water valuation studies to represent the dynamic dimension of irrigation was shown to result in overestimation of derived water values. Water values are also shown to be dramatically influenced by both application system characteristics, as well as the relative costs of irrigation inputs. Finally, the marginal value of irrigation water was shown to vary considerably over the irrigation season, reaching its maximum when atmospheric demand is highest and crops are most susceptible to water stress. Results presented should be of interest to policymakers investigating the viability of alternative water reallocation mechanisms.     

稻田稻麦两熟养鱼生态结构及功能研究

田间试验表明，深沟窄畦结构扩大了稻田生物的生境容量，畦麦沟鱼、稻鱼共生结构提高了稻田生产力，稻麦年产量稳定达到10．84～11.83t／ha，鱼产量3.11～4.20t／ha，在稻田产出中鱼占有最大产值优势度，系统能流结构表现出新特点，生态效率高。     

翻转式堆肥反应装置设计研究

以复合微生物菌剂降解垃圾的适宜条件为出发点 ,根据堆肥小试实验结果 ,确定进料垃圾特性、合理的工艺参数及一次发酵完成时间 ,结合制备装置材料的保温性、堆肥物料平衡、热量平衡 ,合理确定反应装置容积、供气方式、操作运行条件 ,开发了翻转式堆肥反应装置。该装置具有堆料搅拌均匀、进出料简单、供气均衡等特点     

稻油不同轮作模式对农田甲烷和氧化亚氮排放的影响

以南方稻区不同轮作模式为研究对象,采用静态箱-气相色谱法研究水稻-油菜轮作处理的甲烷（CH₄）和氧化亚氮（N₂O）排放特征,并估算稻田增温潜势（GWP）和温室气体排放强度（GHGI）.结果表明,双季稻田、一季中（晚）稻田、油菜地和休闲地CH₄平均排放量分别为135.25,55.64、5.05和1.89 kg ·hm^-2,稻季CH₄排放占不同轮作周年CH₄排放的91.8%~98.5%,稻田土壤水溶性有机碳与CH₄排放呈显著正相关,常规晚稻稻田CH₄排放比杂交晚稻高18.7%（P<0.05）;双季稻田、一季中（晚）稻田、油菜地和休闲地N₂O平均排放量分别为0.94、0.64、1.38和0.24 kg ·hm^-2,油菜地的N₂O排放占周年排放的57.2%~70.2%,双季稻和一季稻处理的冬闲农田N₂O排放占周年排放的17.8%和30.6%,杂交稻和常规稻稻田N₂O排放无显著性差异;双季稻-冬闲和双季稻-油菜的GWP处理高于稻-油和稻-冬闲处理,稻季排放CH₄的GWP占轮作周年GWP排放的71.2%~90.9%;GHGI以稻-稻-油菜最高,稻-油和稻-冬闲处理较低,综合环境效益和经济效益,建议南方稻区选择杂交晚稻-油菜的种植模式,有利于南方多熟制稻田的温室气体减排.     

中国作物秸秆资源利用潜力的多适宜性综合评价

由于作物秸秆类型不同,其营养成分和利用价值也不同,因此仅根据草谷比系数法以质量形态衡量其利用价值,难以全面直接地反映秸秆资源的多种利用价值.为综合定量评价不同利用方式下我国作物秸秆资源的各种利用价值,依据能量流动定律,构建作物秸秆多适宜性综合统一评价体系.结果表明:①以质量、能量和谷物当量3种形态综合核算我国秸秆资源量,其计量结果年际变化趋势较为一致,并且能量和谷物当量形态更能直接体现秸秆资源能源化和饲料化的实际利用价值;②1991-2015年我国作物秸秆资源利用价值总量整体上升,至2015年我国作物秸秆肥料化、基料化和原料化形态质量为6.88×1011 kg,能源化利用价值为8.89×1018 J,适宜饲料化的作物秸秆资源利用量为6.26×1011 kg谷物当量,折合当年全国粮食总产量的100.66%,因此秸秆饲料化具有较高的利用价值,并且符合当前我国"粮改饲"农业改革发展方向;③我国各地秸秆资源量在空间上呈现出显著的地域边缘属性,秸秆资源丰富地区主要集聚在华北、东北和长江中下游地区.研究显示,就作物秸秆主要利用方式而言,饲料化具有相对较高的适宜性和利用价值,但是由于经济收益、经营规模和市场供需不对称等原因,当前农户秸秆饲料化的意愿不高,可利用经济和政策等措施引导该产业有序开展.      

秸秆露天焚烧典型大气污染物排放因子

利用烟气污染物稀释采样系统,基于实际测试,针对玉米、小麦、花生和棉花4种农作物秸秆开展露天焚烧排放大气污染物采集和分析.利用修正燃烧效率区分燃烧状态,根据碳平衡法计算烟气中颗粒物和气态污染物排放因子.结果表明,4种秸秆露天焚烧CO、SO₂、NO_x和CH₄平均排放因子分别在7.39~92.4g/kg、0.11~0.89g/kg、0.72~3.86g/kg和0.2~5.45g/kg之间,PM_2.5平均排放因子在1.48~13.29g/kg之间.OC和EC的质量分别占PM_2.5全部质量的27.7%~54.3%和4.4%~17.1%,是PM_2.5的主要组成成分.污染物排放主要来自混合燃烧状态,焖烧状态排放污染物浓度相对较高.随着含水率升高,焖烧过程增强显著,CO、CH₄、PM_2.5和OC的排放因子升高,其中PM_2.5排放量增高主要是由OC排放占比升高导致.