Assessing desertification risk using system stability condition analysis

This paper describes a procedure for evaluating the desertification risk in threatened areas. The procedure is based on an eight-equation dynamic model of a generic human–resource system that can be applied to different desertification syndromes. For each application, interest focuses on finding all the possible long-term final states of the system and on defining the conditions that mark out sustainability and long-term desertification by means of unambiguous specific parameter relations. The procedure is applied to three typified cases in Spain: (A) rainfed crops in areas with high soil erosion risk; (B) irrigated intensive agricultural systems; and (C) commercial rangelands. Results show that, in case A, high profit scenarios are responsible for the final extension of desertification but do not determine the specific threshold between sustainability and desertification. They do, however, in cases B and C.     

Distribution and Use of Income from Bushmeat in a Rural Village,Central Gabon

Abstract: Bushmeat hunting is an activity integral to rural forest communities that provides a high proportion of household incomes and protein requirements. An improved understanding of the relationship between bushmeat hunting and household wealth is vital to assess the potential effects of future policy interventions to regulate an increasingly unsustainable bushmeat trade. We investigated the relationship between hunting offtake and household wealth, gender differences in spending patterns, and the use of hunting incomes in two rural forest communities, Central Gabon, from 2003 to 2005. Households in which members hunted (hunting households) were significantly wealthier than households in which no one hunted (nonhunting households), but within hunting households offtakes were not correlated with household wealth. This suggests there are access barriers to becoming a hunter and that hunting offtakes may not be the main driver of wealth accumulation. Over half of the money spent by men in the village shop was on alcohol and cigarettes, and the amount and proportion of income spent on these items increased substantially with increases in individual hunting offtake. By contrast, the majority of purchases made by women were of food, but their food purchases decreased actually and proportionally with increased household hunting offtake. This suggests that the availability of bushmeat as a food source decreases spending on food, whereas hunting income may be spent in part on items that do not contribute significantly to household food security. Conservation interventions that aim to reduce the commercial bushmeat trade need to account for likely shifts in individual spending that may ensue and the secondary effects on household economies.     

Farming dynamics and social capital: A case study in the urban fringe of Mexico City

Urban development has important implications for farmland preservation and natural resource management in local peri-urban communities. Social science research on recent changes in rural landscape of mega-cities tends to be limited to case studies in Latin-American nations. This study analyses the socioecomic dynamics of farming land use and the interactions between multiple cultural variables and the environment. Fieldwork was carried out during the 2002–2003 period in rural livelihoods of the five high mountain towns of south Mexico City. Data obtained from participatory survey and ethnographic techniques were integrated to assess changes in rural landscape and resource management and how urbanization, deforestation and market oriented agricultural production result in different livelihoods within a similar urban fringe context. The dynamic of mixture of urban and rural landscapes is based on farm productivity and social capital factors. The study concludes that policy support for regional agricultural production systems through enhancing ecosystems services, environmental protection and economic development is needed for sustainable development of local communities. Readers should send their comments on this paper to BhaskarNath@aol.com within 3 months of publication of this issue     

Solving the United States National Park overflight controversy

By mid-1990 the National Park Service (NPS) must present to Congress recommendations for managing overflights of at least ten national parks. The authors examine the potential role of formal negotiation in setting overflight policy in these parks by reviewing the overflight controversy at Grand Canyon National Park (GCNP). Regulations controlling overflights of the GCNP are only now being implemented after a 17-year conflict that culminated in a congressionally mandated solution. The authors review this controversy and find that, contrary to common perception, the number of park visitors bothered by overflights is not small but roughly equals the number of airborne visitors (up to 450,000 per year). On the basis of this investigation, the authors determine that formal negotiation would have been an appropriate policy-making process because of the clearly defined and limited number of parties and issues involved. Considering the number of park visitors that will continue to be affected by this issue, the authors conclude that formal negotiations should be considered for overflight problems involving other parks. Such negotiations should be park-specific. Differences in park size, extent of the problem, and parties involved would prohibit park-wide negotiations.This article has been adapted from Tourist Flights over the Grand Canyon: The Potential for Negotiated Solutions to Similar Problems, Analysis and Management, October 30, 1987. The opinions expressed in this article are those of the authors; they are not meant to represent the views of the organizations with which the authors are associated.     

Biodiversity Conservation in Agricultural Landscapes: Challenges and Opportunities of Coffee Agroforests in the Western Ghats,India

Abstract: The new approaches advocated by the conservation community to integrate conservation and livelihood development now explicitly address landscape mosaics composed of agricultural and forested land rather than only protected areas and largely intact forests. We refer specifically to a call by Harvey et al. (2008) to develop a new approach based on six strategies to integrate biodiversity conservation with sustainable livelihoods in Mesoamerican landscape mosaics. We examined the applicability of this proposal to the coffee agroforests of the Western Ghats, India. Of the six strategies, only one directly addresses livelihood conditions. Their approach has a clear emphasis on conservation and, as currently formulated risks repeating the failures of past integrated conservation and development projects. It fails to place the aspirations of farmers at the core of the agenda. Thus, although we acknowledge and share the broad vision and many of the ideas proposed by this approach, we urge more balanced priority setting by emphasizing people as much as biodiversity through a careful consideration of local livelihood needs and aspirations.     

陕南移民搬迁与后续增收途径响应研究

同传统的推拉理论引起的移民相比,陕南脱贫攻坚移民具有政府行为的特点,它将自然演进中形成的劳动者与分散耕地相匹配格局打破,出现了劳动者与土地分离的局面,可能造成搬迁后生计不可持续问题。因此,探讨移民搬迁后续增收途径对于促进移民“稳得住”具有十分重要的理论与现实意义。抽取陕南汉中、安康、商洛3市9县584户搬迁家庭作为样本进行实地问卷调查及访谈,通过对调研数据分析发现：（1）搬迁距离对农户生活质量及收入方式产生影响,搬迁距离在2 km以内为适宜距离,社区规模在500户以下,农户最为满意;（2）搬迁距离会引起农户收入方式的转变,搬迁距离越远,农户无法继续使用原有土地等生产生活资料,农业生产发展缓慢,农技水平也相对滞后,使得农户务农收入减少,收入方式向务工转变;（3）就近安置、提升移民人力资本、兴办安置地产业等举措是解决移民户收入来源的可选途径。     

Strengthening artisanal mining research and policy through baseline census activities

Over the past 10–15 years, several governments have implemented an array of technology, support‐related, sustainable livelihoods (SL) and poverty‐reduction projects for artisanal and small‐scale mining (ASM). In the majority of cases, however, these interventions have failed to facilitate improvements in the industry's productivity and raise the living standards of the sector's subsistence operators. This article argues that a poor understanding of the demographics of target populations has precipitated these outcomes. In order to strengthen policy and assistance in the sector, governments must determine, with greater precision, the number of people operating in ASM regions, their origins and ethnic backgrounds, ages, and educational levels. This can be achieved by carrying out basic and localized census work before promoting ambitious sector‐specific projects aimed at improving working conditions in the industry.     

汽车代用燃料及应用前景

介绍了已经开发使用的代用燃料氢气，甲醇，乙醇，新配方汽油，天然气，液化石油气，电动汽车等，并对代用燃料车和汽油车的环境安全性，成本，能耗消耗等方面作了比较，指出天然气，液化石油气是当前最有前途的代用燃料。     

Smallholder Agroforestry Systems For Carbon Storage

Most smallholder agroforestry systems in Southeast Asia are tree- and species-rich systems producing non-wood and wood products for both home use and market sale. Due to their high biomass, these systems contain large carbon (C) stocks. While the systems of individual farmers are of limited size, on a per area basis smallholder systems accumulate significant amounts of C, equaling the amount of C stored in some secondary forests of similar age. Their ability to simultaneously address smallholders’ livelihood needs and store large amounts of C makes smallholder systems viable project types under the Clean Development Mechanism (CDM) of the Kyoto Protocol, with its dual objective of emissions reduction and sustainable development. Smallholder systems have not developed in areas where enabling conditions do not exist. A CDM project that facilitates a minimum threshold of enabling conditions that make smallholder agroforestation possible should qualify for C credits. To secure smallholder confidence, the agroforestry systems promoted through a CDM project must be socially and economically viable independent of C payments. To assure system productivity and profitability, projects should provide farmers with technical and marketing assistance. Additionally, project sites should meet the following preconditions: areas of underutilized low-biomass landuse systems available for rehabilitation; smallholders interested in tree farming; accessible markets for tree products; supportive local governments; sufficient infrastructure; and transparent and equitable relationships between project partners. Questions of leakage and additionality should not be problematic and can be addressed through the project design, establishment of quantifiable baseline data and facilitating enabling conditions. However, smallholder-focused CDM projects would have high transaction costs. The subsequent challenge is thus to develop mechanisms that reduce the costs of: (a) making information (e.g., technology, markets) more accessible to multiple clients; (b) facilitating and enforcing smallholder agreements and (c) designing feasible monitoring systems.     

Population frequencies of alternative male phenotypes in tree lizards: geographic variation and common-garden rearing studies

Tree lizards (Urosaurus ornatus) vary in throat fan (dewlap) color. Earlier, we described five dewlap types (Orange, Orange-Blue, Yellow, Yellow-Blue, and Blue), and reported that only males had blue in the dewlap and that presence or absence of a discrete blue patch was correlated with male alternative reproductive phenotypes in a central Arizona population. Here, with a modified scheme characterizing two dewlap elements, background color (orange, yellow, blue) and blue patch occurrence, we assessed: (1) sexual, annual, and geographic variation in the frequencies of dewlap elements; (2) simple habitat correlates; and (3) the effects of laboratory rearing regime on dewlap type. Within a population, frequencies of males and females expressing orange or yellow backgrounds did not differ, suggesting that control of background is similar in the sexes. Within several populations, frequencies of the dewlap elements did not differ across years (and probably generations), indicating that phenotype frequencies are relatively stable. Among five populations frequencies of background colors varied, as did frequencies of male types (blue patch present or absent). Dewlap frequencies did not correlate with habitat (boulders or mesquite trees), although few populations were sampled. In male and female offspring reared from eggs to sexual maturity in a common-garden laboratory study, background color frequencies in both sexes and blue patch frequencies in males differed among offspring from different populations. Offspring frequencies matched respective parental population frequencies. Results suggest that among-population variation in frequencies of the two dewlap elements are mediated by differences in genetics, in maternal effects, or both. Thus, differences in male behavior functionally linked to the blue patch also may be controlled by genetic or maternal effects. Received: 17 January 1997 / Accepted after revision: 30 August 1997