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451.
Poverty, hunger and demand for agricultural land have driven local communities to overexploit forest resources throughout
Ethiopia. Forests surrounding the township of Humbo were largely destroyed by the late 1960s. In 2004, World Vision Australia
and World Vision Ethiopia identified forestry-based carbon sequestration as a potential means to stimulate community development
while engaging in environmental restoration. After two years of consultation, planning and negotiations, the Humbo Community-based
Natural Regeneration Project began implementation—the Ethiopian organization’s first carbon sequestration initiative. The
Humbo Project assists communities affected by environmental degradation including loss of biodiversity, soil erosion and flooding
with an opportunity to benefit from carbon markets while reducing poverty and restoring the local agroecosystem. Involving
the regeneration of 2,728 ha of degraded native forests, it brings social, economic and ecological benefits—facilitating adaptation
to a changing climate and generating temporary certified emissions reductions (tCERs) under the Clean Development Mechanism.
A key feature of the project has been facilitating communities to embrace new techniques and take responsibility for large-scale
environmental change, most importantly involving Farmer Managed Natural Regeneration (FMNR). This technique is low-cost, replicable,
and provides direct benefits within a short time. Communities were able to harvest fodder and firewood within a year of project
initiation and wild fruits and other non-timber forest products within three years. Farmers are using agroforestry for both
environmental restoration and income generation. Establishment of user rights and local cooperatives has generated community
ownership and enthusiasm for this project—empowering the community to more sustainably manage their communal lands. 相似文献
452.
453.
Grant E. Brown Maud C. O. Ferrari Patrick H. Malka Marie-Anne Oligny Matthew Romano Douglas P. Chivers 《Behavioral ecology and sociobiology》2011,65(6):1267-1276
Under conditions of spatial and/or temporal variability in predation risk, prey organisms often rely on acquired predator
recognition to balance the trade-offs between energy intake and risk avoidance. The question of ‘for how long’ should prey
retain this learned information is poorly understood. Here, we test the hypothesis that the growth rate experienced by prey
should influence the length of the ‘memory window’. In a series of laboratory experiments, we manipulated growth rate of juvenile
rainbow trout and conditioned them to recognize a novel predator cue. We subsequently tested for learned recognition either
24 h or 8 days post-conditioning. Our results suggest that trout with high versus low growth rates did not differ in their
response to learned predator cues when tested 24 h post-conditioning. However, trout on a high growth rate exhibited no response
to the predator cues after 8 days (i.e. did not retain the recognition of the predator odour), whereas trout on a lower growth
rate retained a strong recognition of the predator. Trout that differed in their growth rate only after conditioning did not
differ in their patterns of retention, demonstrating growth rate after learning does not influence retention. Trout of different
initial sizes fed a similar diet (percent body mass per day) showed no difference in retention of the predator cue. Together,
these data suggest that growth rate at the time of conditioning determines the ‘memory window’ of trout. The implications
for threat-sensitive predator avoidance models are described. 相似文献
454.
An inquiry into the concept of SEA effectiveness: Towards criteria for Chinese practice 总被引:2,自引:0,他引:2
Olivia Bina Wu Jing Lex Brown Maria Rosário PartidárioAuthor vitae 《Environmental Impact Assessment Review》2011,31(6):572-581
The importance of improving the effectiveness of Plan EIA and SEA-type evaluations in China cannot be overstated: at a time when the country's economy is being boosted by a stimulus package worth over RMB 400 trillion – largely for infrastructure – the pressure on China's already strained environment and resource base is bound to increase. The aim is to propose the criteria for plan EIA's effectiveness to raise the awareness of the need to strengthen the performance of the assessment and maximize its potential benefits. The authors first review critically the discourse on the effectiveness of the impact assessment, identifying three dimensions: substantive, procedural and incremental. The resulting conceptual framework allows them to interpret the weaknesses of the Chinese discourse on the effectiveness and of the practice of the Plan EIA to date. The result is the identification of a clear gap, both in terms of the breadth of the concept, and in terms of the quality of the existing criteria, which tend to be very generic to the point of inapplicability. The analysis also reveals a need for transitioning from formal models of the Plan EIA to more strategic approaches, in a gradual manner that is consistent with context-specificities. The proposal of a set of preliminary criteria for effectiveness is therefore structured on three levels. This framework is meant to input into the ongoing debate on how to improve the practice of PEIA and the SEA-type evaluations in China, and provide ideas for a government strategy aimed at maximizing the positive impact of PEIAs on planning, as well as on the context of application. 相似文献
455.
Peanut hull pellets as a single use sorbent for the capture of Cu(II) from wastewater 总被引:1,自引:0,他引:1
This paper investigates the ability of peanut hulls and peanut hull pellets to adsorb copper from dilute aqueous metal ion solutions in batch and fixed bed systems. The kinetics of copper uptake onto the media have been investigated in batch systems and the influence of pH and particle size on the rate and extent of copper capture determined. The Langmuir and Freundlich isotherm theories were determined; the Langmuir model was found to best represent the equilibrium isotherm data. In normalized kinetic tests at least 75% of copper removal occurred within the first 20 min; 92% removal was effected within the first 50 min. The rate of uptake was optimum within the pH range 5-7.5, and media capacities remained relatively constant at a pH above 4.0. Bench-scale column studies were performed using peanut hull pellets. The overall capacity of pelletized peanut hulls was higher than for unmodified peanut hulls. Due to their demonstrated ability for Cu(II) uptake and favorable structural characteristics, pelletized peanut hulls could gain use as a low-cost, once-through biomass filter medium for copper-bearing waste streams. 相似文献
456.
The article advances the hypothesis that the seasonal and inter‐annual variability of rainfall is a significant and measurable factor in the economic development of nations. An analysis of global datasets reveals a statistically significant relationship between greater rainfall variability and lower per capita GDP. Having established this correlation, we construct a water resources development index that highlights areas that have the greatest need for storage infrastructure to mitigate the impacts of rainfall variability on water availability for food and basic livelihood. The countries with the most critical infrastructure needs according to this metric are among the poorest in the world, and the majority of them are located in Africa. The importance of securing water availability in these nations increases every day in light of current population growth, economic development, and climate change projections. 相似文献
457.
458.
Indicator kriging is used to estimate the probability that a discrete area of soil (known as an exposure unit) lies either above or below an action level, warranting a response of either remediation or “no further action.” Resampling procedures are introduced as a way to optimize the number of additional samples needed to meet desired Type I and Type II error rates. This article provides the reader a step-by-step guide to the kriging analysis and a case study illustrating the procedures. 相似文献
459.
460.
With parks and protected areas insufficient to sustain global biodiversity, the role of private land in biodiversity conservation is becoming increasingly significant. This paper reviews global voluntary and involuntary strategies for private land conservation. Involuntary strategies can achieve effective conservation outcomes, but often lack social acceptability. In contrast, voluntary strategies enjoy greater social acceptance but may not achieve sufficient uptake to have meaningful conservation objectives. Based on the review, we propose a classification system for private land conservation as a complement to the International Union for Conservation of Nature's (IUCN's) classification of global protected areas. The classification system provides a framework for identifying and describing conservation strategies on private land on the dimension of tenure and security. It also identifies opportunities and vulnerabilities in achieving conservation on private land while emphasising the need for systematic data collection similar to IUCN's efforts for protected areas. 相似文献