草原生态补偿:生态绩效、收入影响和政策满意度

草原生态保护补助奖励机制的第一轮实施期(2011-2015)即将结束,系统地评估草原生态保护补助奖励机制,对于完善下一期补助奖励机制具有重要的借鉴意义。本文利用2014年内蒙古自治区阿拉善左旗、四子王旗、陈巴尔虎旗三个旗县的470户牧户样本数据,从生态绩效、收入影响、政策满意度三个方面对草原生态补偿政策(即草原生态保护补助奖励机制)进行了评估。生态绩效评估结果表明:草原生态环境得到了一定的改善,草原利用方式更趋合理,平均牲畜超载率下降明显,但超载过牧的现状没有得到根本的转变,样本调研旗县2011-2014年减畜任务达成比例为42%,总体减畜任务达成情况一般。收入影响评估结果表明:平均每户理论收入影响为-8 607元,草原生态补偿标准偏低,需要在原有基础上提高35%;平均每户的实际收入影响为16 686元,牧民没有严格按照政策要求进行完全的减畜;草原生态补偿标准不只是单纯标准偏低的问题,同时也有标准差别化问题,需要在不同地区之间做出调整。政策满意度评估结果表明:草原生态补偿政策的满意度为57%,其中陈巴尔虎旗的政策满意度最高,为87%;四子王旗其次,为62-63%;阿拉善左旗最低,为18-32%。政策满意度与实际收入影响之间存在显著的相关关系,实际收入影响正向越大,政策满意度越高。牧民对草原生态补偿政策的政策满意度越高,并不意味着草原生态补偿的政策设计和执行就越好,政策满意度越高,实际收入影响正向越大,但生态效果可能不佳。     

基于证据权重法的呼伦贝尔地区人为草原火险空间预测

应用证据权重法结合GIS空间分析,研究了呼伦贝尔地区人为草原火险。利用证据权重法定量化地分析了与人类活动密切相关的5个因子(乡村人口密度、载畜密度、居民点分布、城镇分布、公路网)与草原火点空间分布的关系,并建立了呼伦贝尔草原火险预测模型,据此在ARCVIEW的WofE扩展模块下生成一幅草原火险预测专题图,并将研究区划分为高、中、低三类风险区。研究表明:(1)呼伦贝尔草原火灾火点的空间分布与人类活动关系密切,尤其是乡村人口密度、公路网与居民点分布这三个因子,权重分别为0.5191,0.1945,0.2864;(2)证据权重法可以客观定量地表现出草原火险与人类活动的关系,因而可为草原火灾风险管理提供决策支持。     

Environmental contamination, human exposure and body loadings of perfluorooctane sulfonate (PFOS), focusing on Asian countries

Perfluorinated compounds (PFCs) are man-made fluorinated hydrocarbons, which are very persistent in the environment. Since the early 1980s, the usage of PFCs has sharply increased for a wide array of industrial and commercial applications. Being the most important PFC, perfluorooctane sulfonate (PFOS) has received much attention. In the past decades, increasing surveys have been focused on this compound, to study its sources, fates and effects in the environment. According to the large production volume and wide usage in industrial and commercial products in the past, PFOS can be detected in various environmental media and matrix, even in human tissues. This article attempted to review the current status of PFOS contaminations in Asia, focusing on water systems, sediments, wide animals and human tissues. A special section is devoted to examine the pathways of human exposure to this compound, as well as human body loadings of PFOS and their possible association with diseases.     

Observed cold season changes in a Fennoscandian fell area over the past three decades

We studied trends and variability in snow and climate characteristics in 1978–2012 in the Värriötunturit fell area, northern Finland. Cold season changes were examined using long-term observational data on snow depths, meteorological data, large-scale climate indices, and reindeer herders’ experiences with difficult snow conditions. Snow depths declined, and temperatures increased significantly over the study period, with the largest changes observed in October–December and in April. Snow depths decreased particularly in forests at lower altitudes but not in treeless areas at higher altitudes. Interannual variability (but not the trends) in snow depths could be partially linked to large-scale climate indices. A majority of difficult reindeer grazing conditions were related to deep snow in the winter or spring. Our observations suggest that shortened duration of snow cover may facilitate reindeer grazing, whereas potentially more frequent formation of ice layers and mold growth on pastures in the future is disadvantageous for reindeer husbandry.     

动物细胞的简单控制模型

动物细胞的体外培养需要多种生长因子。本研究假设Ｖｅｒｏ细胞生长和对营养物的吸收利用与一个关键生长密切相关,一个控制变量ｃ控制这一关键生长因子的合成。根据这假设建立了一个简单的Ｖｅｒｏ细胞生长的控制模型,该模型较好地描述了细胞从延迟期到静止期的整个生长过程。     

天然草地利用方式改变对土壤排放CO2 和吸收CH4的影响

1997年～ 1998年在内蒙古达拉特旗中国农业科学院草原研究所草原生态试验站对天然草地、天然草地转变为人工草地、玉米和土豆地后 ,土壤 CO2 排放和 CH4 吸收通量进行了测定。天然草地、人工草地和旱地农田均为大气中甲烷的吸收汇 ,天然草地转变为农田后 ,增强了土壤的 CO2 排放量 ,减少了土壤对大气中甲烷的吸收。天然草地和玉米地的 CO2 排放通量与 5cm处土壤温度呈线性相关 ,土壤对甲烷的吸收率与土壤含水量呈线性负相关 ,与土壤温度没有相关关系     

Socioeconomic Dimensions of Changes in the Agricultural Landscape of the Mediterranean Basin: A Case Study of the Abandonment of Cultivation Terraces on Nisyros Island,Greece

Agricultural landscapes illustrate the impact of human actions on physical settings, and differential human pressures cause these landscapes to change with time. Our study explored changes in the terraced landscapes of Nisyros Island, Greece, focusing on the socioeconomic aspects during two time periods using field data, cadastral research, local documents, and published literature, as well as surveys of the islanders. Population increases during the late 19^th to early 20^th centuries marked a significant escalation of terrace and dry stone wall construction, which facilitated cultivation on 58.4% of the island. By the mid-20^th century, the economic collapse of agricultural activities and consequent emigration caused the abandonment of cultivated land and traditional management practices, dramatically reducing farm and field numbers. Terrace abandonment continued in recent decades, with increased livestock grazing becoming the main land management tool; as a result, both farm and pasture sizes increased. Neglect and changing land use has led to deterioration and destruction of many terraces on the island. We discuss the socioeconomic and political backgrounds responsible for the land-use change before World War II (annexation of Nisyros Island by the Ottoman Empire, Italy, and Greece; overseas migration opportunities; and world transportation changes) and after the war (social changes in peasant societies; worldwide changes in agricultural production practices). The adverse landscape changes documented for Nisyros Island appear to be inevitable for modern Mediterranean rural societies, including those on other islands in this region. The island’s unique terraced landscapes may qualify Nisyros to become an archive or repository of old agricultural management techniques to be used by future generations and a living resource for sustainable management.     

基于虹膜识别的肉类食品可追溯系统研究

为了加强食品安全管理,提高肉类食品溯源准确性的目的,首先提出肉类食品溯源体系的3个基本要素,认为:动物个体识别是肉食品质量控制的重要环节;采用虹膜识别作为大型动物个体识别的关键技术;解决了其他动物识别系统中的欺骗以及设备功能异常现象等问题。以奶牛为例,讨论人眼虹膜识别技术应用于大型动物识别在图像采集、虹膜定位、特征提取3方面存在的技术难点;给出了实现动物虹膜识别的技术路线;最后构建了基于虹膜识别的肉食品可追溯系统。通过详细功能划分和流程设计,为虹膜技术在肉食品可追溯系统中的应用实施提供了参考。     

3种人工草地不同植被覆盖度实地测量方法比较

植被覆盖度是植被垂直投影面积占统计区域面积百分比;理想覆盖度实地测量方法耗时短,工具简单,结果准确,受人为因素影响小.以结缕草(Zoysia japonica)、白三叶(Trifolium repens)和雀稗(Paspalum thunbergii)人工草地为研究对象,以照相法测量值为参考,比较样线法、目估法、样针法...     

基于集对原理的天然草地分类方法

本文首次将集对原理用于天然草地分类中,以中国新疆某地区的31个天然草地为例进行计算,并将分析结果,与灰色关联度分析法、投影寻踪法以及投影寻踪动态聚类法作了对比分析。结果表明,集对法与三种方法分析结果一致,但集对法计算简单,使用方便,不受样本容量限制,且能清晰和形象地显示所属类别的程度,在多因素聚类分析中具有广阔的应用前景。