Results 61 to 70 of about 4,056 (198)
Advocacy strategies in state preemption: The case of energy fuel bans
Abstract Interest group literature suggests reformer advocacy groups, seeking policy change and innovation, are more likely to secure policy victory in local government. Entrenched advocacy groups, favoring current policies, are better suited to win policy battles at the state level.
Cory L. Struthers, Cary Ritzler
wiley +1 more source
Manifesting symbolic representation through collaborative policymaking
Abstract Collaboration is a widely employed strategy for addressing “wicked” policy problems. While scholars have long recognized that the organizational composition of collaborative forums can have a dramatic impact on the efficacy and equity of associated forum outputs, little is known about whether such composition impacts the manner in which ...
Jack Mewhirter +2 more
wiley +1 more source
Influence of mining-induced ground fissures on soil infiltration characteristics and its erosion effect in coal mining area of northern Shaanxi in the middle reaches of the Yellow River [PDF]
Cracking the soil and water loss effects of mining-induced surface fissures in the coal mining area of the middle reaches of the Yellow River is of great significance for ecological environment protection and high-quality development in the coal mining ...
Baodeng CHEN +6 more
core +1 more source
为分析南水北调(中线)丹江口库区不同土地利用方式土壤团聚体稳定性及其分形特征,揭示人类活动对土壤结构的影响,以库区内不同土地利用方式(水田、旱地、果园、人工林地、自然林地)土壤为研究对象,经干筛和湿筛法测定团聚体组成,以土壤团聚体稳定性指标(大团聚体含量(R>0.25)和团聚体破坏率(PAD))、土壤团聚体直径指标(平均质量直径(MWD)和几何均重直径(GMD))以及分形维数(D)作为评价指标,对比分析丹江口库区不同土地利用方式下土壤团聚体组成及其稳定性。结果表明,对土壤团聚体组成的测定 ...
姜, 刘, 刘
doaj
The Long-term Variations and Influencing Factors of Soil Saturated Hydraulic Conductivity in Terraces on the Loess Plateau [PDF]
[Objective] The long-term variations of soil saturated hydraulic conductivity (Ks) and its primary controlling factors in terraces on the Loess Plateau were explored. [Methods] Terraces were selected for three land use types, i.e.
CHANG Heng +6 more
core +1 more source
United in disagreement: Analyzing policy networks in EU policy making
Abstract Shared belief systems are generally assumed to forge policy networks. Empirical evidence whether and to what extend shared policy core beliefs create ally networks and under which circumstances shared policy core beliefs are not necessary to form these networks, however, is limited.
Dennis Abel, Armin Mertens
wiley +1 more source
为探讨不同恢复方式对大兴安岭重度火烧迹地土壤团聚体形成及其团聚体碳循环的影响,以大兴安岭1987年重度火烧后分别经过人工恢复(兴安落叶松、樟子松)和天然恢复的林分为研究对象,分析不同恢复方式下土壤团聚体有机碳、团聚体微生物量碳和团聚体K2SO4浸提碳的分布特征。结果表明:(1)不同林型间土壤团聚体有机碳含量、团聚体微生物量碳含量和团聚体K2SO4浸提碳含量差异显著(P<0.05),其大小关系均是兴安落叶松人工林>天然次生林>樟子松人工林。(2)在不同植被恢复方式下 ...
李红运, 辛 颖, 赵雨森
doaj
海洋是地球上最大的碳库,发挥着全球气候变化缓冲器的作用.蓝色碳汇,简称蓝碳,即由海洋生态系统捕获的碳(主要是有机碳),是海洋储碳的重要机制之一.; 蓝碳最初认识的形式是可见的海岸带植物固碳.其实之前没有得到足够重视的、看不见的微型生物(浮游植物、细菌、古菌、病毒、原生动物)占海洋生物量90%; 以上,是蓝碳的主要贡献者.中国陆架边缘海占国土总面积的1/3,碳汇潜力巨大,亟待研发.本文以近海生态系统碳汇过程、调控机制及增汇模式为主线,论述; 了近海生态系统结构与碳循环功能特征、碳汇形成过程与机理 ...
严重玲 +16 more
core +1 more source
用湿筛法和LeBissonnais法研究了鄂南第四纪红粘土母质发育的两种侵蚀程度的红壤团聚体的稳定性,并且分析了影响供试土壤团聚体稳定性的土壤性质。结果表明,轻度侵蚀的耕作土壤团聚体的稳定性较低,在水的作用下易崩解成较小粒径的水稳性团聚体;强度侵蚀的土壤表层团聚体的稳定性较高,崩解后产生较多的水稳性大团聚体。引起土壤团聚体破坏的主要作用机制是土壤团聚体中的闭蓄空气爆破引起的消散作用;研究区第四纪红壤团聚体的主要胶结物质是土壤中的粘粒、游离氧化铁铝和无定形铁。由于供试土壤中有机质含量很低,在本研究中 ...
李朝霞 蔡崇法 史志华 王天巍 张琪 孙站成
doaj +2 more sources
为探明地面覆盖对核桃园土壤团聚体特征的影响,研究了地面覆盖后核桃园土壤的微团聚体分布、大团聚体分布及大团聚体化学计量特征。结果表明:在20—40 cm土层,覆盖有机肥处理的10~150 μm粒径的微团聚体百分含量为84.52%,较对照提高了3.7%;1~5 mm粒径的大团聚体百分含量为47.74%,较对照提高了56.8%;>5 mm粒径的大团聚体百分含量为33.04%,较对照降低了49.5%。覆盖处理显著提高了土壤全效养分含量,在0—20 cm土层,覆盖有机肥处理的所有径级团聚体全氮、全磷 ...
孙, 齐国辉, 张雪梅
doaj

