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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
2.
针对某乡镇企业十分发达地区的跨行政(市县)区域水污染死鱼事故的剖析,本文提出了处理解决跨行政区域水污染纠纷事故的若干对策建议。 相似文献
3.
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
4.
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
5.
南水北调的资源、环境和社会效应 总被引:6,自引:0,他引:6
俞澄生 《长江流域资源与环境》1994,3(3):265-270
建设南水北调工程,对中国的水资源在地区间进行合理调配,将带动其他资源的合理配置与利用,还可改善环境,是社会发展的需要,又受社会条件制约,一旦突破建成,将促使社会生产力发生新的飞跃并持续发展。 相似文献
6.
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
7.
Linden F Vincent 《Natural resources forum》2003,27(2):108-116
Situations of water scarcity challenge sustainability and threaten small users' access to water. In response to this problem, there has been a search for a method of hydrological analysis that can better represent the needs of small water users. While this search is rooted in the debate favouring a more participatory and inclusive allocation of the resource, it also requires a new focus on smallholder hydrology that can confront the gaps and biases found in current hydrological practices in many countries. This article looks at past hydrological practices and also at results of recent studies, highlighting the perspective of smallholder irrigators in surface water planning in Zimbabwe, and groundwater planning in India. These case studies show that wider social forces, not always best science, drive hydrological practices. However, new frameworks focusing on the water user can emerge for more equitable and sustainable water management. 相似文献
8.
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
9.
Wastewater reclamation and reuse has been proved to be an effective way to relieve the fresh water crisis. However, toxic contaminants remaining in reclaimed water could lead to potential risk for reuse, and the conventional water quality standards have difficulty guaranteeing the safety of reclaimed water. Bioassays can vividly reflect the integrated biological effects of multiple toxic substances in water as a whole, and could be a powerful tool for evaluating the safety of reclaimed water. Therefore, in this study, the advantages and disadvantages of using bioassays for evaluating the safety of reclaimed water were compared with those of conventional water quality standards. Although bioassays have been widely used to describe the toxic effects of reclaimed water and treatment efficiency of reclamation techniques, a single bioassay cannot reflect the complex toxicity of reclaimed water, and a battery of bioassays involving multiple biological effects or in vitro tests with specific toxicity mechanisms would be recommended. Furthermore, in order to evaluate the safety of reclaimed water based on bioassay results, various methods including potential toxicology, the toxicity unit classification system, and a potential eco-toxic effects probe are summarized as well. Especially, some integrated ranking methods based on a bioassay battery involving multiple toxicity effects are recommended as useful tools for evaluating the safety of reclaimed water, which will benefit the promotion and guarantee the rapid development of the reclamation and reuse of wastewater. 相似文献
10.
This study profiled the bacterial community variations of water from four water treatment systems, including coagulation, sedimentation, sand filtration, ozonation-biological activated carbon filtration (O3-BAC), disinfection, and the tap water after the distribution process in eastern China. The results showed that different water treatment processes affected the bacterial community structure in different ways. The traditional treatment processes, including coagulation, sedimentation and sand filtration, reduced the total bacterial count, while they had little effect on the bacterial community structure in the treated water (before disinfection). Compared to the traditional treatment process, O3-BAC reduced the relative abundance of Sphingomonas in the finished water. In addition, ozonation may play a role in reducing the relative abundance of Mycobacterium. NaClO and ClO2 had different effects on the bacterial community in the finished water. The relative abundance of some bacteria (e.g. Flavobacterium, Phreatobacter and Porphyrobacter) increased in the finished water after ClO2 disinfection. The relative abundance of Mycobacterium and Legionella, which have been widely reported as waterborne opportunistic pathogens, increased after NaClO disinfection. In addition, some microorganisms proliferated and grew in the distribution system, which could lead to turbidity increases in the tap water. Compared to those in the finished water, the relative abundance of Sphingomonas, Hyphomicrobium, Phreatobacter, Rheinheimera, Pseudomonas and Acinetobacter increased in the tap water disinfected with NaClO, while the relative abundance of Mycobacterium increased in the tap water disinfected with ClO2. Overall, this study provided the detailed variation in the bacterial community in the drinking water system. 相似文献