Carbon Emission by Soils in Forests Damaged by the Siberian Moth

In the southern-taiga low grass–green moss fir forest completely defoliated by the Siberian moth, the rate of soil respiration in the third year after the pest population outbreak was 1.5 times higher than in an undisturbed tree stand. This was explained by a significant increase in the abundance and activity of soil microorganisms in the pest-defoliated forest, which occurred due to the qualitative changes in the litter composition and the increased temperature and moisture in the upper soil layers. The rate of carbon emission from the soil in the defoliated forest was 41.7 kg/ha per day, compared to 28.3 kg/ha per day in the undisturbed fir forest.     

Analysis of Trophic Indices in Gypsy Moth (Lymantria dispar L.) Larvae from Two Geographic Populations

Specific features of larval feeding in two geographic populations of the gypsy moth are considered. It is shown that in larvae reared on an artificial diet, trophic indices depend on several factors, including the age and sex of larvae and the food plant on which the parental generation developed in nature. It is shown that larval micropopulations belonging to the same geographic population but feeding in nature on different plant species differ from each other to a greater extent than those of different geographic populations feeding on the same species.     

Relationship between the Population Dynamics of the Gypsy Moth (Lymantria dispar L., Lymantriidae: Lepidoptera) and the Genetic Polymorphism of the Nuclear Polyhedrosis Virus

The population dynamics of the gypsy moth and the genomic DNA of the nuclear polyhedrosis virus (NPV) pathogenic for this insect were simultaneously studied using nucleic acid molecular hybridization (NAMH). It was demonstrated that population outbreaks of the gypsy moth were accompanied by an increase in its sensitivity to NPV and in the genetic polymorphism of NPV strains circulating in the insect populations. The hybridization activity of the virus strains isolated at the phase of gypsy moth population growth was significantly higher (p < 0.001) than the activity of the strains isolated at the phase of population decrease.     

黄淮海地区水土资源粮食安全价值核算

水土资源是粮食生产和粮食安全的基础.水土资源粮食安全价值核算对于促进水土资源可持续利用,平衡地区粮食生产任务促进粮食安全具有积极意义.目前国内尚未有关于水土资源粮食安全价值系统的核算方法.本文根据虚拟水和虚拟土理论,综合考虑自然、经济和社会因素对粮食安全的影响,构建了粮食生产中的水土资源粮食安全价值核算方法体系,并以黄淮海地区为例进行了实证分析.结果表明:水土资源的粮食安全价值真实存在且可以量化,黄淮海地区各省市水土资源的粮食安全价值存在差异,河北、江苏、安徽、山东和河南省的水土资源粮食安全价值总量远远高于北京和天津,并提出了建立粮食安全补贴完善粮食安全价值实现途径的政策建议.     

Ecology of Nuclear Polyhedrosis Virus in Western Siberian Populations of the Gypsy Moth (<Emphasis Type="Italic">Lymantria dispar</Emphasis> L.)

The impact of the nuclear polyhedrosis virus on the population dynamics of the gypsy moth Lymantria dispar L. has been studied. The results have shown that polyhedrosis morbidity in the western Siberian population of the insect is relatively low, compared to that reported for North American and European populations. A possible cause of this situation is found in the high migration activity of moths in the Asian L. dispar populations, which allows the virus load on the biotope to remain relatively stable and insufficient for the initiation of mass viral diseases during population outbreaks.__________Translated from Ekologiya, No. 3, 2005, pp. 222–226.Original Russian Text Copyright © 2005 by Ilinykh.     

对退耕还林中农民选择权认识的经济学分析

农户决策行为和反应机制无疑是考察项目可持续性的一个重要方面。本文应用微观经济学理论．结合退耕还林工程的实际情况．提出理论假说：贫瘠土地退出种植是经济发展到一定水平的自发结果。并根据三省遐耕还林的实际调查数据。采用计量模型对退耕还林农户选择权认识问题进行检验。研究结果表明退耕还林工程的可持续性还存在一定隐患，退耕还林工程不仅要和当地的经济发展紧密结合。在操作方法上还需进一步改进。     

基于农业生态地带模型的中国粮食产能动态评估

随着人口增加和人们生活水平的不断提高,我国粮食消费需求将继续呈刚性增长,使得粮食品种和区域结构性矛盾加剧,而粮食产能的动态评估能够让我们加深认识我国粮食供需平衡,对制定适宜于我国经济社会发展同时保障粮食安全的粮食可持续发展战略具有重要意义.论文选取农田生产力作为我国粮食产能的指标,通过改进农业生态地带(AEZ)模型,动态嵌入不同县域水平的管理和投入水平的限制性因子,集成县级截面数据估计投入系数权重,并基于此估算了全国2000-2010年间农田生产力水平.研究发现,2000年以来,我国农田生产力虽年际间存在波动,但总体呈现增长的态势,且区域差异性显著.农田生产力水平存在从沿海到内陆、从南向北及从东向西的递减的梯度,而局部地区农田生产力变化明显,表现出明显的东西分异规律,其次是南北分异规律.而对各个地区农田生产力平均值统计发现,东部沿海地区与南部省份的农田生产力要高于内陆省份,西部地区农田生产力普遍低于东部和中部地区.2000、2005、2010年全国分县统计的粮食产量数据与动态估算结果进行精度验证,其相关系数分别达到0.82、0.76和0.89,实际产量为估算结果的69.4％、73.4％、67.2％,较好的反映了我国农田生产力的基本状况.最后,基于我国农田生产力时空变化规律和局部差异性特征,以及我国经济区水平上的中国农田生产力的变化规律,从耕地数量保障、农业管理和投入水平提高以及适宜的农业区划方面,提出适宜于我国自然环境状况和社会经济发展的农田生产力保障策略,对保障我国的农田生产力的稳定增长方面的规划决策与政策制定具有参考价值.     

黄土高原水土流失区生态退耕对粮食生产的可能影响

根据黄土高原水土流失区有关各省区制定的退耕规划,分析了生态退耕对粮食生产产生的可能影响。(1)生态退耕将直接减少粮食147.92×104t,由此退耕还林还草可能会带来粮食产量的暂时下降。(2)从生态退耕的正面影响看,退耕节省下来的生产要素的转移可以带来未退耕耕地粮食产量的增加;同时技术进步、中低产田改造等农业基础设施的建设和生态环境的改善,势必也对粮食生产产生促进和推动作用。(3)粮食需求预测表明,2010年黄土高原水土流失区粮食总量将达1 400.71×104t,在人均400kg,425kg和450kg水平下粮食需求分别为1 389.34×104t,470.37×104t和1 563.01×104t。从A方案看,就黄土高原水土流失区整体而言将不会出现粮食短缺;但具体到分区而言,黄土丘陵区必须通过粮食调入才能满足本区需求,而黄土台塬区则有一定盈余。     

城镇化对粮食生产环境技术效率影响研究

我国粮食生产在实现了"十一连增"之后正面临着城镇化所带来的资源约束和环境挑战,如何实现城镇化与粮食生产的协调发展,是我国当前需要高度关注的一个重大问题。本文以1994-2012年我国29个省(市、区)为研究对象,利用方向距离函数将环境因素纳入到粮食生产技术效率测算框架,对我国粮食生产环境技术效率值进行了测算,并对不同阶段各粮食生产功能区粮食生产环境技术效率的演变特征进行了分析,在此基础上将城镇化细分并设置了人口城镇化指标、土地城镇化指标、产业发展城镇化指标和生态环境压力城镇化指标,利用所构建面板数据模型探讨了城镇化对粮食生产环境技术效率的影响。研究结果表明:11994-2012年城镇化加速期,我国粮食主产区和主销区的粮食生产与环境的协调度要优于粮食平衡区,但是粮食主产区和主销区的粮食生产环境在逐步恶化,粮食平衡区则在逐步好转;2人口城镇化有利于粮食主销区和平衡区粮食生产环境技术效率提升,对粮食主产区则相反。土地城镇化、产业发展城镇化和生态环境压力城镇化不利于全国及各粮食生产功能区粮食生产环境技术效率的提升;3城镇化对粮食生产环境技术效率的影响存在功能区差异性。     

退耕还林与贫困地区粮食安全的实证分析--以宁夏回族自治区为例

本文以实证分析的方法,以宁夏地区为例,通过研究该地区2003年200户退耕户和100户非退耕户之间。以及二者与1999年实行退耕还林政策前的人均粮食消费量和人均食品支出水平的变化,认为退耕户的粮食安全程度比非退耕户和退耕前的农户有了显著的提高,这种提高与农民的人均收入水平和人均耕地面积呈正相关,而与粮食播种面积比重呈负相关,因而可得得出结论：在生态脆弱地区实行退耕还林政策并不会影响当地农民的粮食安全。     

Economic analysis of effects on cultivated land following China's entry to the WTO

Inspired by the phenomenon of heavy reduction in the area of cultivated land following the entry of Korea and Japan to the WTO,countries with a large population and inadequate amount of cultivated land similar to China,this paper raises the problem of the potential effects on cultivated land in China following its entry to the WTO.The paper attempts analysis,using economic principles,of the effects of Chinese WTO membership on cultivated land from four aspects;tariff concessions,quota increment,comparative advantage,and the substitution principle.And the conclusion is mat China's entry to WTO may lead to a reduction in cultivated land.Finally,some countermeasures are proposed to resolve the problem.     

Carabids in a Spring Wheat Agrocenosis to the South of Sverdlovsk Oblast and the Effect of Insecticide Treatment on Their Populations

Species composition, community structure, and seasonal population dynamics of carabids in spring wheat fields were studied in the vicinity of Yekaterinburg. In addition, the effects of crop treatment with the pyrethroid insecticide Decis on carabid populations was analyzed. The results showed that the numbers, species diversity, and the prevalence of certain trophic groups of carabids changed during the season. After the treatment of small areas with Decis, the number of carabids in catches decreased for a short period of time. During the second and third weeks after the treatment, the numbers of carabids increased above the control level. The structural rearrangement of the carabid community was observed in the areas treated with the insecticide.     

The Grain-population Relationship and the Effect of Main Food Producing Areas in China

With the increase of global population, grain-popula- tion relationship has attracted great attention worldwide. In China, grain-population relationship has become an increasingly impor- tant economic ...     

1990～2015年长江流域县域粮食生产与粮食安全时空格局演变及影响因素分析

长江流域粮食生产与经济发展在全国均占据重要地位,研究近25年长江流域粮食生产与粮食安全时空格局演变及影响因素,可为我国粮食安全及流域可持续发展提供科学依据。基于1990、1995、2000、2005、2010和2015年长江流域县域粮食产量、户籍人口数据、农业化肥使用量和粮食播种面积（740个区县）,运用粮食变化指数、探索性空间数据分析（ESDA）、重心转移模型和空间误差模型(SEM)研究其时空格局演变特征及影响因素。研究结果表明：（1）1990～2015年长江流域粮食产量总体呈增长趋势,东西差异显著,年均增长率为0.5%,上中下游依次为0.6%、0.8%和 -0.7%;上游为劣势区,中游为优势增长区,下游为减弱区。（2）粮食产量冷点聚类一直分布在上游地区,聚类格局在2000年左右由西南边界的“L”型转变为西北倒“L”型;下游江淮地区与太湖平原的热点集聚在2000年后消失,且长期处于减产状态;人均粮食占有量与粮食产量时空格局演变呈较高的空间相似性,2000年为流域粮食生产与粮食安全格局发生变化的转折点。（3）1990～2015年长江流域一般余粮县和重要余粮县重心呈现出“南下西移”态势,缺粮县和供需紧平衡县重心发生了“从南向北、从西向东”迁移变化。（4）粮食播种面积和农业化肥施用量对粮食生产均具显著性正向效益。     

Arachnids (Arachnidae) in a Spring Wheat Agrocenosis in Southern Sverdlovsk Oblast and the Effect of Treatment with Decis,a Pyrethroid Insecticide,on Their Populations

Russian Journal of Ecology -     

Estimated heavy metal emissions to the atmosphere due to projected changes in the Brazilian energy generation matrix

An estimate of heavy metals emissions to the atmosphere due to the projected changes in the Brazilian energy generation fuel matrix is presented. Present use of fossil fuel combustion for energy production is projected to increase from the present 14.5% to 29.6% of the total energy generation in Brazil in 2005. Most of this increase will be based on coal- and natural-gas-burning plants. The changes will result in an increase of about 100% in the average emissions (in tons year⁻¹) of As (9.4 to 17.7), Cr (7.0 to 16.6) and Hg (2.4 to 4.1), 50% of Cd (1.2 to 1.8), and 20% of Ni (101 to 123) and Pb (23.3 to 29.9). Although relatively small for most heavy metals when compared to other industrial sources, the changes in the energy matrix will be particularly important for Hg, reaching a maximum emission of 12 tons (t) year⁻¹, representing 15% of the total emissions of Hg to the atmosphere in Brazil. The use of Brazilian coals and the location of most coal-burning plants in a relatively small region in the south of the country strongly suggest that monitoring programs should be implemented during the building of the new plants. At a regional level the expected increase in Hg emissions to the atmosphere due to coal burning in Brazil, although small relative to North America and Europe, will equal the total amount estimated for South and Central America.     

Radionuclide transfer to fruit in the IAEA TRS 364 Revision

Information on the transfer of radionuclides to fruits was almost absent in the former TRS 364 “Handbook of parameter values for the prediction of radionuclide transfer in temperate environments”. The revision of the Handbook, carried out under the IAEA Programme on Environmental Modelling for RAdiation Safety (EMRAS), takes into account the information generated in the years following the Chernobyl accident and the knowledge produced under the IAEA BIOMASS (Biosphere Modelling and Assessment) Programme in the years 1997–2000. This paper describes the most important processes concerning the behaviour of radionuclides in fruits reported in the IAEA TRS 364 Revision and provides recommendations for research and modelling.     

Ecoagrochemical Approaches to the Problem of Nitrate Pollution in Agroecosystems

On the basis of long-term studies, the role of agricultural chemicals in enhancing the production process and the rate of nitrate accumulation in plants is shown. Their influence on the state of plants is evaluated from physiological and agrochemical standpoints. The possibility of improving the resistance of agroecosystems to various adverse factors is considered.     

Dealing with uncertainty in the assessment of human exposure to radioactivity in food and the environment

This paper presents an overview of the approach used to assess radiation dose and risk to members of the public from radioactivity in food and the environment. It describes uncertainties in the process and suggests ways of dealing with them to improve the risk assessment process. It also explains how uncertainty in the assessed dose/risk can be communicated to non-expert audiences such as members of the public. The issues covered in this paper apply to risk assessment of any contaminant and not only radioactivity.