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1.
Crop damage is the most common impact of negative interactions between people and elephants and poses a significant threat to rural livelihoods and conservation efforts. Numerous approaches to mitigate and prevent crop damage have been implemented throughout Africa and Asia. Despite the documented high efficacy of many approaches, losses remain common, and in many areas, damage is intensifying. We examined the literature on effectiveness of crop-damage-mitigation strategies and identified key gaps in evaluations. We determined there is a need to better understand existing solutions within affected communities and to extend evaluations of effectiveness beyond measurement of efficacy to include rates of and barriers to adoption. We devised a conceptual framework for evaluating effectiveness that incorporates the need for increased emphasis on adoption and can be used to inform the design of future crop-damage mitigation assessments for elephants and conflict species more widely. The ability to prevent crop loss in practice is affected by both the efficacy of a given approach and rates of uptake among target users. We identified the primary factors that influence uptake as local attitudes, sustainability, and scalability and examined each of these factors in detail. We argue that even moderately efficacious interventions may make significant progress in preventing damage if widely employed and recommend that wherever possible scientists and practitioners engage with communities to build on and strengthen existing solutions and expertise. When new approaches are required, they should align with local attitudes and fit within limitations on labor, financial requirements, and technical capacity. 相似文献
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重点开发长江是90年代中国经济重大战略布署。将长江产业带建设成具有强大经济实力的国家一级经济轴线,宜采用分层次推进与中心辐射相结合的发展战略,以浦东开发和三峡建设为契机,加强基础产业,发展新兴产业和第三产业,优化产业结构,以能源和交通建设先行,改善基础设施。同时,要协调产业带建设与浦东开发、三峡工程建设的关系。 相似文献
4.
测试了两种消石灰与垃圾焚烧烟气中HCl的反应率,得出了消石灰的反应率与反应时间的反应曲线,分析了消石灰与HCl的反应机理及影响消石灰最终反应率的因素。试验结果表明,消石灰与HCl反应初期按灰层扩散控制进行,两种消石灰的最终反应率分别为16%和36%。 相似文献
5.
Joachim Ruther 《Chemoecology》2004,14(3-4):187-192
Summary. Field tests were performed to evaluate the
response of the garden chafer, Phyllopertha horticola
(Coleoptera: Scarabaeidae) to known scarab attractants and to
investigate the influence of trap colour and height on the
number of captured beetles. Both sexes were attracted by a
lure mixture composed of geraniol, eugenol, and 2-phenylethyl
propionate (PEP) (ratio 3:7:3). When testing floral volatiles
individually, only geraniol, eugenol and methyl anthranilate
but not PEP was attractive. Response of garden chafer to (Z)-
3-hexen-1-ol was strongly male-biassed. Both the response
to floral volatiles and (Z)-3-hexen-1-ol was increased by
using funnel traps with yellow instead of grey vanes. Traps
positioned at 50 and 125 cm above ground captured significantly
more garden chafers than those at 200 cm. The
strongly male-biassed response to (Z)-3-hexen-1-ol suggests
that in P. horticola (subfamily Rutelinae) orientation towards plant volatiles emitted upon mechanical damage of plants is
part of the male mate finding strategy as recently demonstrated
for cockchafers of the genus Melolontha (subfamily Melolonthinae). Possible application of plant volatiles for
control of P. horticola is discussed. 相似文献
6.
生态工业建设为生态示范区建设的重要内容之一 ,是一项涉及到地区经济发展、人地关系协调的重大举措。从生态示范区建设中生态工业的基本定义出发 ,对生态工业建设层次进行详尽分析 ;并结合代表江苏省苏南、苏中和苏北不同社会经济发展水平的三个地区——吴县市、邗江县和邳州市的具体案例 ,通过对其产业构成、主导产业、消费结构以及经济发展总量与人均水平的对比分析 ,指出经济发展水平较低的地区要立足当地农业资源 ,实施末端治理并逐步推广清洁生产这种较低层次的生态工业建设模式 ;而经济发展较好的地区其生态工业的建设则要采用生态企业以及生态工业园区这种较高层次的建设模式。为确保生态工业建设的顺利实施 ,最后从政府、企业、市场和公众四方面提出了生态工业建设的驱动机制 相似文献
7.
电感耦合等离子体质谱法在环境监测中的应用 总被引:2,自引:0,他引:2
针对ICP-MS技术的使用特点及其近年来在环境监测领域的应用进行综合阐述,并对ICP-MS技术的发展前景作出简单的评述。 相似文献
8.
9.
外源8''-炔基脱落酸强化东南景天吸收重金属的研究 总被引:1,自引:0,他引:1
为探究脱落酸类似物8''-炔基脱落酸[8''-(C2H)ABA]强化东南景天富集重金属的效应,通过水培的方法研究了外源8''-(C2H)ABA分别对Cd(20 mg·L-1)、Zn(160 mg·L-1)单一胁迫下东南景天Cd/Zn积累和生理特性的影响,以及初步探讨了8''-(C2H)ABA在植物重金属胁迫响应中的作用.实验结果表明:与天然ABA相比,外源8''-(C2H)ABA能达到与ABA类似的作用效果,且对Cd胁迫下东南景天促进效果好于Zn;在Cd胁迫下,与对照相比,外源8''-(C2H)ABA能显著增加东南景天根、叶中的Cd含量(44.2%、27.5%),以及光合色素(10.7%)和叶中过氧化物酶(SOD)活性(52.9%)、超氧化物歧化酶(POD)(24.7%)和过氧化氢酶(CAT)活性(27.9%)抗氧化酶活性,使可溶性糖(SS)(13%)和游离脯氨酸(Pro)(37.4%)含量增加,而叶中丙二醛(MDA)(40%)含量明显降低.上述结果表明,一定浓度的8''-(C2H)ABA可以提高东南景天抗氧化酶活性来增强其对重金属Cd的抗性及吸收和转运能力,在强化东南景天修复重金属污染方面具有应用潜力. 相似文献
10.
Glycine(Gly) is ubiquitous in the atmosphere and plays a vital role in new particle formation(NPF).However,the potential mechanism of its on sulfuric acid(SA)-ammonia(A)clusters formation under various atmospheric conditions is still ambiguous.Herein,a(Gly)_x·(SA)_y·(A)_z(z≤x+y≤3) multicomponent system was investigated by using density functional theory(DFT) combined with Atmospheric Cluster Dynamics Code(ACDC) at different temperatures and precursor concentrations.The results show that Gly,with one carboxyl(-COOH) and one amine(-NH_2) group,can interact strongly with SA and A in two directions through hydrogen bonds or proton transfer.Within the relevant range of atmospheric concentrations,Gly can enhance the formation rate of SA-A-based clusters,especially at low temperature,low [SA],and median [A].The enhancement(R) of Gly on NPF can be up to 340 at T=218.15 K,[SA]=10~4,[A]=10~9,and [Gly]=10~7 molecules/cm~3.In addition,the main growth paths of clusters show that Gly molecules participate into cluster formation in the initial stage and eventually leave the cluster by evaporation in subsequent cluster growth at low [Gly],it acts as an important "transporter" to connect the smaller and larger cluster.With the increase of [Gly],it acts as a "participator" directly participating in NPF. 相似文献