陕北—黄土区生态户的生态建设是实现黄土高原生态恢复的重要步骤——党家山生态农户考察的启发

生态户是构成生态环境的最小单元,它既是一切生态建设措施的落脚点,也是促使陕北农民走出贫困、实现小康的奠基石。解决黄土高原的问题最为根本的是保护和合理利用水资源,通过生态户的建设,整合有关水土保持措施,使其长期稳定地发挥生态效益,最终促进陕北多沙粗沙区生态环境的根本性好转。必须实施重点突破战略,采取典型引路的方式,层层落实、步步为营,一点一点地治理,积少成多,绝不反复,最后实现全面好转。     

陕北一黄土区生态户的生态建设是实现黄土高原生态恢复的重要步骤——党家山生态农户考察的启发

生态户是构成生态环境的最小单元,它既是一切生态建设措施的落脚点,也是促使陕北农民走出贫困、实现小康的奠基石.解决黄土高原的问题最为根本的是保护和合理利用水资源,通过生态户的建设,整合有关水土保持措施,使其长期稳定地发挥生态效益,最终促进陕北多沙粗沙区生态环境的根本性好转.必须实施重点突破战略,采取典型引路的方式,层层落实、步步为营,一点一点地治理,积少成多,绝不反复,最后实现全面好转.     

陕北能源开发与生态环境保护法律对策研究

陕北生态环境区可分为风沙滩地区和黄土丘陵沟壑区。风沙滩区的防沙治沙问题和黄土丘陵沟壑区的水土保持问题是陕北能源开发以前就存在的生态环境老问题。陕北能源开发引起的生态环境新问题主要是地貌和植被破坏严重,生态环境退化;地面塌陷、地下水位下降,居民生活受到影响;水土流失、土地沙化、自然灾害增加;废水、废气超标排放。陕北能源开发过程中生态环境日趋破坏的法律原因是生态补偿过于概括,缺乏可操作性;税收法律法规及地方规章规定的资源税率太低,税收分配比例不合理;环境影响评价制度的要求未能被全面适用。陕北能源开发中进行生态环境保护应选择的法律对策是坚持生态效益与经济效益相统一的环境法原则;完善生态环境法补偿机制;提高陕北资源税率,并在分配比例上适当照顾资源开发区人民的利益;制定环保产业规章制度,研究和引进先进的生产工艺。     

陕北地区煤炭资源开采过程中的生态破坏与对策

陕北地区的煤炭资源开发给当地造成了严重的环境污染和生态破坏,对陕北地区煤炭开发给环境造成的大气污染、水污染、固体废弃物污染损失和给生态造成水源短缺、水土流失、植被破坏等损失分别进行经济计量,综合评价了陕北地区煤炭资源开发的生态环境价值损失。     

陕北沙地景观生态类型与土地优化配置

在分析陕北毛乌素沙地环境背景的基础上，进行了景观生态类型划分和演替模式的系统研究。着眼于建立人地协调关系系统，以景观生态学理论和可持续发展思想为指导，提出土地生态设计和土地优化配置的模式与措施。     

宁夏生态移民效益评价研究

生态移民工程是实现生态环境脆弱区环境-经济-社会可持续发展的重要举措。文中从生态移民工程的3大目标出发,建立起一套评价指标体系,选用两种方法定量化评价了宁夏生态移民的生态效益、经济效益、社会效益。结果表明:宁夏先期生态移民综合效益良好,呈现出逐年上升的趋势;生态效益最为显著,有效遏制了生态退化势头,显著改善了迁出区的生态环境;移民的生产条件得到了改善,经济状况逐渐好转,社会环境显著改观;但在经济发展过程中依然存在结构不合理、发展潜力不足等问题。     

典型沙漠化地区农户对生态环境变化的感知与适应——以内蒙古自治区杭锦旗为例

沙漠化地区生态环境十分脆弱,理解农户对生态变化的感知与适应策略选择倾向对于制定科学的生态环境治理政策至关重要。采用参与式的农村评估法(PRA)对地处库布其沙漠腹地的杭锦旗不同区域农户的生态环境变化感知与适应进行了调查与对比分析。结果发现:与2000年相比,大部分农户认为当地的生态环境好转了。其中,牧区受访户对生态好转的认知度低于农区;为改善生态环境,农户在生态保护政策的引导下,采取了向二三产业转移劳动力、改变养殖模式、减少牲畜数量、抽取地下水、精耕细作等措施应对生态环境变化。除精耕细作外,牧区农户采用其他适应策略的比例均远高于农区;农户对生态环境变化的感知与适应具有区域差异性和空间层次性,农户对经济机会的响应影响着其对生态环境变化的感知与适应策略选择,并在此基础上提出了改善当地生态环境的政策建议。     

陕北丘陵沟壑区发展生态草畜产业的思考

实施退耕还林还草之后,种草养畜是陕北丘陵沟壑区重要的后续产业,成为农民增收新的突破口。挖掘发展草畜业的资源优势和潜力,采用扩大苜蓿种植、实行舍饲养羊发展节粮型畜牧业、发展草畜产品的加工和综合利用、建立健全服务体系等措施,应遵循生态学原理和循环经济理念,从牧草生产源头抓起,严格防止草畜生产各环节的污染,全面建设生态草畜业,实现区域生态经济可持续发展。     

基于改进遥感生态指数模型的锡林郭勒草原生态环境评价

气候变化和人类活动的不断加剧,引发了生态环境质量问题,快速准确的评价区域生态环境的历史和现状,对实现人与自然的可持续协调发展具有重要意义。本文基于遥感技术分别反演出绿度因子、湿度因子、干度因子和热度因子,使用主成分分析法构建了改进遥感生态指数(MRSEI)。利用相关性分析,分析MRSEI的代表性,建立基于MRSEI的锡林郭勒草原生态环境评价模型,对锡林郭勒草原近26 a的生态环境进行了总体评价。结果表明:MRSEI可集中4种生态因子信息,能够准确的对生态环境进行评价;锡林郭勒草原从1991—2017年生态环境质量呈现出先好转后恶化的趋势; 1991年研究区上游的生态环境质量优于下游,生态环境质量东部优于西部; 2004年,研究区整体生态环境质量空间差异较1991年变化较大,上游大多数地区生态环境质量提升,但下游明显降低;至2017年,整个研究区生态环境质量全面降低,仅在锡林河上游两岸与流域的南部和东南部保持良和优良。     

河西走廊生态脆弱性评价及其恢复与重建

河西走廊是西部大开发的重点建设区域之一，其良好的生态环境质量是实现区域经济社会持续发展的重要保证。本文在分析河西走廊主要生态环境问题的基础上，建立了生态脆弱性评价的相关指标体系，对全区19个县市进行了生态脆弱的量化评价，并提出了生态恢复与重建的基本对策。     

Arbuscular mycorrhizal fungal community of wheat under long-term mineral and organic amendments in semi-arid Mediterranean Turkey

A minimal amount of information is currently available concerning arbuscular mycorrhizal (AM) fungal associations with crops in semi-arid zones on Leptosols in Turkey. Therefore, using molecular ecological techniques, we studied the effects of different management practices (without fertilization, chemical fertilization, farmyard manure, and plant compost amendments) on AM fungal communities associated with wheat roots. Experiments were conducted in a field established in 1996 in southern Mediterranean Turkey where soil productivity is low owing to unfavorable climatic effects and soil characteristics. We determined 201 partial sequences of AM fungal nuclear ribosomal large subunit genes. The higher AM fungal richness was found in the control treatment without fertilization and plant compost treatments compared with the chemical fertilization and farmyard manure treatments. Clones related to Rhizophagus were found in all treatments and accounted for 37% of the total AM fungal clones, whereas those of Funneliformis were dominant under chemical fertilization. Redundancy analysis based on the frequency of operational taxonomic units revealed that AM fungal communities were divided into three groups, namely, the control treatment, the chemical fertilization treatment, and the organic treatments (farmyard manure and plant compost treatments). Although different organic amendments supported relatively similar AM fungal communities, plant compost induced higher AM fungal richness than farmyard manure fertilization.     

Evaluation of fungicide application rates,spray schedules and alternative management options for rust and angular leaf spot of snap beans in Uganda

Yield losses due to rust and angular leaf spot (ALS) of snap beans may reach 100% in Eastern Africa. Where susceptible varieties are grown, farmers control these diseases with routine fungicide applications. To determine an optimum application rate and spray schedule for Orius® (tebuconazole 250 g/L), we sprayed 10 mL and 20 mL Orius® per 15 L spray water twice at two trifoliate leaf stage and 50% flowering, and three times at the same stages, with an additional application at pod initiation. In farmers’ fields, we tested the effect of fungicide sprays, use of resistant variety, intercropping, increased plant spacing and farmyard manure on rust and ALS diseases. Application three times of 20 mL Orius® per 15 L spray water reduced rust severity scores by 5.7 and 2.4 in 2010 and 2011, respectively. Lowest rust and ALS severities were observed when a resistant variety, fungicide or farmyard manure was used. Pod yield increments due to disease management ranged between 13% and 242%. Prophylactic fungicide application, use of resistant varieties and farmyard manure can be used to reduce disease severity and improve snap bean quality on smallholder farms.     

Seed germination and viability of herbicide resistant and susceptible Chenopodium album populations after ensiling,digestion by cattle and manure storage

Chenopodium album became a problem weed in sugar beet production, due to resistance to metamitron, a key herbicide in this crop. Dispersal of the seeds from resistant biotypes may occur due to spread by wind, animals, agricultural machinery or manure. This study examined the effect of ensiling, digestion by cattle and storage in slurry and farmyard manure on the germination and viability of the seeds of one susceptible and three resistant C. album populations. After 4 weeks in a maize silo, seed viability of C. album populations was reduced drastically to 0–5%. Incubation for 24 h in the rumen followed by a post‐ruminal digestion in vitro of intact seeds only resulted in a small reduction in viability in one C. album population. Storage in a slurry cellar for 16 weeks reduced the viability of intact seeds of the C. album populations to 25–60%. Only 0–1% of the seeds remained viable after storage in a farmyard manure heap for 4 weeks. An accelerated ageing experiment showed seed persistence to be population specific and less related to seed weight. Keeping a fresh maize silo closed for at least 4 weeks and heaping farmyard manure are excellent preventive measures to limit the spread of resistant C. album seeds between fields.     

Soil type, management history, and soil amendments influence the development of soil-borne (Rhizoctonia solani, Pythium ultimum) and air-borne (Phytophthora infestans, Hyaloperonospora parasitica) diseases

The impact of soil type, long-term soil management, and short-term fertility input strategies on the suppressiveness of soils against soil-borne (Ocimum basilicum – Rhizoctonia solani, Lepidium sativum – Pythium ultimum) as well as air-borne (Lycopersicon esculentum – Phytophthora infestans, Arabidopsis thaliana – Hyaloperonospora parasitica) diseases was studied. Soils from field trials established in five European sites with contrasting pedo-climatic conditions were examined. Sites included (i) a long-term management field trial comparing organic and conventional farming systems (DOK-trial, Therwil, Switzerland) (ii) a short-term fertility input field trial comparing mineral and organic matter fertilisation regimes (Bonn (BON), Germany) (iii) two short-term fertility input field trials (Stockbridge (STC) and Tadcaster (TAD), UK) comparing the impact of farmyard manure, composted farmyard manure, and chicken manure pellet amendements and (iv) soil from a site used as a reference (Reckenholz (REC), Switzerland). Soil type affected disease suppressiveness of the four pathosystems signficantly, indicating that soils can not only affect the development of soil-borne, but also the resistance of plants to air-borne diseases at relevant levels. Suppressiveness to soil- and air-borne diseases was shown to be affected by soil type, but also by long-term management as well as short-term fertility inputs.     

《民法典》实施背景下生态环境损害赔偿诉讼定位研究

《生态环境损害赔偿制度改革方案》所构建的生态环境损害赔偿诉讼乃是以国家所有权为请求权基础的私益诉讼。省级、市地级政府基于《改革方案》以国家所有权为请求权依据提起私益诉讼在法理上存在障碍,只能作为生态环境损害赔偿救济的权宜之计。《民法典》生效后,《改革方案》已完成其历史使命,不宜再作为提起生态环境损害赔偿诉讼的规范依据。生态环境损害赔偿诉讼究其本质乃为维护公益而展开的公益诉讼。《民法典》将作为特殊公益诉讼的生态环境损害赔偿诉讼之起诉主体由法律规定的机关扩大至国家规定的机关,体现了绿色原则。《民法典》为《民事诉讼法》第55条规定生态环境损害赔偿公益诉讼提供了实体法依据,实现了该畛域实体法与程序法的有机结合。     

基于时间维度的旅游环境承载力动态研究

旅游环境承载力是描述旅游环境系统能够承受的旅游活动强度的概念,是建立在微观研究基础上服务于旅游区规划管理的重要工具。合理、科学的构建旅游环境承载力动态模型,对维护旅游业的可持续发展有着重要的理论意义和实践价值。本文首先分析了旅游环境承载力的内涵;再次,根据旅游业发展的季节性特征,运用动态改进层次分析法确定不同阶段的权重,遵循从分量承载力计量到综合承载力计量的步骤构建旅游环境承载力的动态模型;最后,为了反映旅游环境承载力的利用状况,增强实用性,对旅游环境承载率进行了研究,并以南戴河国际娱乐中心旅游区为例进行了实证分析。     

祟仁余干两地封山育林控制松毛虫效果初探

本文通过对祟仁、余干两地封山育林控制马尾松毛虫效果的研究。揭示了封山育林是一种安全、经济、有效的控制松毛虫的技术措施,通过封山育林,改变了松林生态环境,增加了松林的生物多样性,提高了松林的抗虫能力。     

一种基于agent随机扩散的图像分割方法

图像分割是图像处理的关键环节,直接影响以后的分析、识别和解译。根据进化agent具有自适应性、非线性映射和高度并行处理能力等优点,提出了一种基于agent随机扩散的图像分割方法。在该方法中,agent点随机地撒在网格单元上,并在满足一致性标准的区域用标签标定。agent点有复制和扩散两种行为扩散模式,当一个agent成功的找到一个像素满足一致性标准,它将在周围区域复制一系列后代,因此这些后代更容易找到那些满足一致性条件的像素,而对于那些超过生命周期的agent点将停止搜索,从环境中消失。利用医学胸部的CT图像和脑部的磁共振图像进行的实验结果表明,该方法能较好地从图像中提出感兴趣的区域。     

陕西省人口与资源环境协调演进分析

人口的发展加重了资源环境的压力,资源环境对人口的发展又构成了约束作用.如何有效度量人口与资源环境的协调程度显得颇为必要.通过构建指标体系,采用改进的TOPSIS方法对1997-2007年陕西省的人口与资源环境协调程度进行了分析,结果表明:1)人口综合发展水平持续升高,由0.1159上升到0.4044.2)资源环境承载能...