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1.
While the negative ecological effects of the rapid expansion of oil palm in Southeast Asia are far-reaching and relatively widely studied, the socioeconomic consequences have received much less attention in the literature. We examine whether local farmers in Indonesia benefit from cultivating oil palm. We also look at the impact dynamics and possible spillover effects on other farmers. Our analysis builds on panel data collected from 680 farm households in Jambi Province, Sumatra. We show that oil palm cultivation has significant positive effects on farmers’ livelihoods. The economic gains allow farm households to increase their consumption. Oil palm has lower labor requirements than alternative crops. Hence, oil palm farmers can cultivate larger areas and also reallocate saved labor time to non-farm economic activities, which contributes to additional secondary gains. Policies aimed at regulating further oil palm area expansion will have to account for the economic benefits of this crop for the local population.  相似文献   

2.
Current agricultural realities dictate that crops be developed which can be grown with fewer petroleum inputs and on marginal croplands. A palm tree native to the Amazon Valley,Jessenia bataua, found in both swamplands and upland forests has been studied. The fruits of this tree have long been exploited by indigenous peoples as a source of oil and a milk-like drink. Chemical analyses of the oil show it to be similar to olive oil. Chemical and biological assays of the mesocarp pulp protein reveal its quality to be comparable to that of good animal protein and considerably better than most grain and legume proteins. Rats fed diets containingJessenia bataua mesocarp oil and pulp showed normal weight gains when compared to those fed diets with similar quanities of corn oil and casein.Jessenia bataua is an example of a little-known wild plant that could provide a new source of food protein and oil for combating world hunger.  相似文献   

3.
The expansion of agriculture into tropical forest frontiers is one of the primary drivers of the global extinction crisis, resulting in calls to intensify tropical agriculture to reduce demand for more forest land and thus spare land for nature. Intensification is likely to reduce habitat complexity, with profound consequences for biodiversity within agricultural landscapes. Understanding which features of habitat complexity are essential for maintaining biodiversity and associated ecosystem services within agricultural landscapes without compromising productivity is therefore key to limiting the environmental damage associated with producing food intensively. Here, we focus on oil palm, a rapidly expanding crop in the tropics and subject to frequent calls for increased intensification. One promoted strategy is to remove epiphytes that cover the trunks of oil palms, and we ask whether this treatment affects either biodiversity or yield. We experimentally tested this by removing epiphytes from four‐hectare plots and seeing if the biodiversity and production of fruit bunches 2 months and 16 months later differed from equivalent control plots where epiphytes were left uncut. We found a species‐rich and taxonomically diverse epiphyte community of 58 species from 31 families. Epiphyte removal did not affect the production of fresh fruit bunches, or the species richness and community composition of birds and ants, although the impact on other components of biodiversity remains unknown. We conclude that as they do not adversely affect palm oil production, the diverse epiphyte flora should be left uncut. Our results underscore the importance of experimentally determining the effects of habitat complexity on yield before introducing intensive methods with no discernible benefits.  相似文献   

4.
Farmers in Africa have long adapted to climatic and other risks by diversifying their farming activities. Using a multi‐scale approach, we explore the relationship between farming diversity and food security and the diversification potential of African agriculture and its limits on the household and continental scale. On the household scale, we use agricultural surveys from more than 28,000 households located in 18 African countries. In a next step, we use the relationship between rainfall, rainfall variability, and farming diversity to determine the available diversification options for farmers on the continental scale. On the household scale, we show that households with greater farming diversity are more successful in meeting their consumption needs, but only up to a certain level of diversity per ha cropland and more often if food can be purchased from off‐farm income or income from farm sales. More diverse farming systems can contribute to household food security; however, the relationship is influenced by other factors, for example, the market orientation of a household, livestock ownership, nonagricultural employment opportunities, and available land resources. On the continental scale, the greatest opportunities for diversification of food crops, cash crops, and livestock are located in areas with 500–1,000 mm annual rainfall and 17%–22% rainfall variability. Forty‐three percent of the African cropland lacks these opportunities at present which may hamper the ability of agricultural systems to respond to climate change. While sustainable intensification practices that increase yields have received most attention to date, our study suggests that a shift in the research and policy paradigm toward agricultural diversification options may be necessary.  相似文献   

5.
In human history technology has had an obvious in fluence on the labour process and division of labour. This paper looks at the impact of introduced technology on the size and composition of labour units required for productive work in Koropata, Papua New Guinea. Although new tools and weapons have made smaller working units more feasible for gardening, hunting and fishing, a network of kin is necessary to ensure long term production in the society. Hence housebuilding and acceptable marriages require the co-operation of kin. A knowledge of technology and co-operative forms should be complemented by an understanding of land ownership and relations of production, if any predictions are to be made about essential changes in organization of production. I claim that the latter has been retained in its essential aspects for subsistence-based production. For the historical involvement of Koropatans in cash-cropping, however, there has been an increasing alienation from the product and loss of control over the labour process as they have moved from the cultivation of rice, to coffee, to oil palm.  相似文献   

6.
Drivers of change in global agriculture   总被引:2,自引:0,他引:2  
As a result of agricultural intensification, more food is produced today than needed to feed the entire world population and at prices that have never been so low. Yet despite this success and the impact of globalization and increasing world trade in agriculture, there remain large, persistent and, in some cases, worsening spatial differences in the ability of societies to both feed themselves and protect the long-term productive capacity of their natural resources. This paper explores these differences and develops a countryxfarming systems typology for exploring the linkages between human needs, agriculture and the environment, and for assessing options for addressing future food security, land use and ecosystem service challenges facing different societies around the world.  相似文献   

7.
Closing yield gaps within existing croplands, and thereby avoiding further habitat conversions, is a prominently and controversially discussed strategy to meet the rising demand for agricultural products, while minimizing biodiversity impacts. The agricultural intensification associated with such a strategy poses additional threats to biodiversity within agricultural landscapes. The uneven spatial distribution of both yield gaps and biodiversity provides opportunities for reconciling agricultural intensification and biodiversity conservation through spatially optimized intensification. Here, we integrate distribution and habitat information for almost 20,000 vertebrate species with land‐cover and land‐use datasets. We estimate that projected agricultural intensification between 2000 and 2040 would reduce the global biodiversity value of agricultural lands by 11%, relative to 2000. Contrasting these projections with spatial land‐use optimization scenarios reveals that 88% of projected biodiversity loss could be avoided through globally coordinated land‐use planning, implying huge efficiency gains through international cooperation. However, global‐scale optimization also implies a highly uneven distribution of costs and benefits, resulting in distinct “winners and losers” in terms of national economic development, food security, food sovereignty or conservation. Given conflicting national interests and lacking effective governance mechanisms to guarantee equitable compensation of losers, multinational land‐use optimization seems politically unlikely. In turn, 61% of projected biodiversity loss could be avoided through nationally focused optimization, and 33% through optimization within just 10 countries. Targeted efforts to improve the capacity for integrated land‐use planning for sustainable intensification especially in these countries, including the strengthening of institutions that can arbitrate subnational land‐use conflicts, may offer an effective, yet politically feasible, avenue to better reconcile future trade‐offs between agriculture and conservation. The efficiency gains of optimization remained robust when assuming that yields could only be increased to 80% of their potential. Our results highlight the need to better integrate real‐world governance, political and economic challenges into sustainable development and global change mitigation research.  相似文献   

8.
Stands of babassu palms (Orbignya martiana) occupy an area of Brazil estimated at nearly 200,000 km2, concentrated in the states of Maranhão, Piauí and Goiás. Babassu’s cryptogeal germination, establishing the apical meristem of the plant below ground for its early growth and development, enables it to survive human disturbance, making the palm an integral part of shifting cultivation and pastoral farming systems. People obtain a multitude of products from babassu throughout the palm’s life cycle: leaves are used widely for thatch, basketry, and construction; trunks for palmito and bridges; the fruit for feed, oil and, charcoal. As many as 450,000 subsistence-level households rely on the sale of babassu kernels, used in a regional vegetable oil industry, for an important share of their cash incomes. Deforestation pressures and technological innovation toward an industry based on mechanical processing of whole babassu fruit threaten to reduce benefits the palm provides to the region’s rural poor. Understanding how babassu is used by rural families who depend upon it will help to make current efforts at “domesticating” the palm and whole-fruit processing more responsive to human needs.  相似文献   

9.
Swidden cultivation was observed to be under pressure but still persisting in many areas in Sarawak, Malaysia around 2000–2003. Since then rapid development of smallholder oil palm and rubber, continuing urbanization and rural to urban migration appear to have considerably reduced the area under swidden cultivation. With the aim of understanding the extent and impacts of this development, 55 households in three communities that were interviewed in 2002–2003 were re-interviewed in 2011. In an area with rapid oil palm development, the households engaged in smallholder oil palm production have experienced considerable improvements in income and wealth whereas the other households have experienced more limited wealth increases or even a decline in income. Many households have decreased or abandoned cultivation of upland rice, which used to be the core of the swidden cultivation system, and the upland soils in the area are now dominated by oil palm. In another area, where no oil palm development has taken place because of a hydroelectric dam, upland rice fields under swidden cultivation have also decreased and new high yielding rubber is now being planted because of the favorable rubber prices. Moreover, tourism has in this area gained further economic importance and overtaken agriculture as the main economic activity of households. The demise of swidden has not yet occurred in Sarawak, but a continued decline has been observed. However, there is a possibility that the new smallholder oil palm and rubber may provide an opportunity for a new type of ‘productive fallow’ that will allow continued cultivation of upland rice on a small scale.  相似文献   

10.

Background

Green algae belong to a group of photosynthetic organisms that occupy diverse habitats, are closely related to land plants, and have been studied as sources of food and biofuel. Although multiple green algal genomes are available, a global comparative study of algal gene families has not been carried out. To investigate how gene families and gene expression have evolved, particularly in the context of stress response that have been shown to correlate with gene family expansion in multiple eukaryotes, we characterized the expansion patterns of gene families in nine green algal species, and examined evolution of stress response among gene duplicates in Chlamydomonas reinhardtii.

Results

Substantial variation in domain family sizes exists among green algal species. Lineage-specific expansion of families occurred throughout the green algal lineage but inferred gene losses occurred more often than gene gains, suggesting a continuous reduction of algal gene repertoire. Retained duplicates tend to be involved in stress response, similar to land plant species. However, stress responsive genes tend to be pseudogenized as well. When comparing ancestral and extant gene stress response state, we found that response gains occur in 13% of duplicate gene branches, much higher than 6% in Arabidopsis thaliana.

Conclusion

The frequent gains of stress response among green algal duplicates potentially reflect a high rate of innovation, resulting in a species-specific gene repertoire that contributed to adaptive response to stress. This could be further explored towards deciphering the mechanism of stress response, and identifying suitable green algal species for oil production.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1335-5) contains supplementary material, which is available to authorized users.  相似文献   

11.
中国如何突破生物柴油产业的原料瓶颈   总被引:72,自引:4,他引:72  
因应我国日益严峻的能源资源、能源环境和能源安全形势,国家大力倡导发展可再生能源。生物柴油是最重要的液体可再生燃料之一,在能源性质方面可以完全替代化石柴油,而且还具有安全环保等其它优良特性。当前利用动植物油脂生产生物柴油,原料成本偏高,而且稳定、充足的油脂原料供应体系尚未形成。我国是油脂资源短缺国家,近年来植物油进口量逐年增加。同时,我国耕地资源匮乏,粮食供应形势不容乐观,扩大油料作物种植的潜力非常有限。但是,我国宜林地丰富,农林废弃生物质资源量巨大。综合以上因素,我国应重点发展木本油料植物规模化种植和推广,加快微生物油脂发酵技术创新和产业化进程;同时,利用植物遗传育种技术提高油料作物产量以及选择性发展不与粮争地的油料作物。依靠各方面的进步,发展创新的油脂生产技术,保障我国生物柴油产业和油脂化工行业健康发展。  相似文献   

12.
Although considerable achievements in the global reduction of hunger and poverty have been made, progress in Africa so far has been very limited. At present, a third of the African population faces widespread hunger and chronic malnutrition and is exposed to a constant threat of acute food crisis and famine. The most affected are rural households whose livelihood is heavily dependent on traditional rainfed agriculture. Rainfall plays a major role in determining agricultural production and hence the economic and social well being of rural communities. The rainfall pattern in sub-Saharan Africa is influenced by large-scale intra-seasonal and inter-annual climate variability including occasional El Ni?o events in the tropical Pacific resulting in frequent extreme weather event such as droughts and floods that reduce agricultural outputs resulting in severe food shortages. Households and communities facing acute food shortages are forced to adopt coping strategies to meet the immediate food requirements of their families. These extreme responses may have adverse long-term, impacts on households' ability to have sustainable access to food as well as the environment. The HIV/AIDS crisis has also had adverse impacts on food production activities on the continent. In the absence of safety nets and appropriate financial support mechanisms, humanitarian aid is required to enable households effectively cope with emergencies and manage their limited resources more efficiently. Timely and appropriate humanitarian aid will provide households with opportunities to engage in productive and sustainable livelihood strategies. Investments in poverty reduction efforts would have better impact if complemented with timely and predictable response mechanisms that would ensure the protection of livelihoods during crisis periods whether weather or conflict-related. With an improved understanding of climate variability including El Ni?o, the implications of weather patterns for the food security and vulnerability of rural communities have become more predictable and can be monitored effectively. The purpose of this paper is to investigate how current advances in the understanding of climate variability, weather patterns and food security could contribute to improved humanitarian decision-making. The paper will propose new approaches for triggering humanitarian responses to weather-induced food crises.  相似文献   

13.
Commercial selective logging and the conversion of primary and degraded forests to agriculture are the biggest threats to tropical biodiversity. Our understanding of the impacts of these disturbances and the resulting local extinctions on the functional roles performed by the remaining species is limited. We address this issue by examining functional diversity (FD), which quantifies a range of traits that affect a species' ecological role in a community as a single continuous metric. We calculated FD for birds across a gradient of disturbance from primary forest through intensively logged forest to oil palm plantations on previously forested land in Borneo, Southeast Asia, a hotspot of imperilled biodiversity. Logged rainforest retained similar levels of FD to unlogged rainforest, even after two logging rotations, but the conversion of logged forest to oil palm resulted in dramatic reductions in FD. The few remaining species in oil palm filled a disproportionately wide range of functional roles but showed very little clustering in terms of functional traits, suggesting that any further extinctions from oil palm would reduce FD even further. Determining the extent to which the changes we recorded were due to under‐utilization of resources within oil palm or a reduction in the resources present is an important next step. Nonetheless our study improves our understanding of the stability and resilience of functional diversity in these ecosystems and of the implications of land‐use changes for ecosystem functioning.  相似文献   

14.
Forest-based farmers are faced with rapidly changing economic opportunities due to many factors. In response, farmers are changing their main economic activities and land uses. This study compares the financial costs and benefits of the principal land use options in two sub-districts of East Kalimantan Province, Indonesia. Financial benefits of oil palm plantation, traditional rattan gardens, intensive rubber plantation, and traditional rubber plantation are compared on a land unit basis. Oil palm is by far the most profitable, followed by rattan gardens. Rubber production, at current prices, is not profitable. Benefit-cost ratios and returns to labor, which better reflect the farmer perspective, reveal that rattan is more attractive, with oil palm in a strong second place. Non-financial considerations also help to explain the resilience of the rattan garden system. The conclusions summarize the findings and offer options to counter the strong negative impact of recent events on the rattan farmers.  相似文献   

15.
The article describes how economic resilience of farming households can be measured using a composite indicator of revealed adaptive actions, and investigates how capabilities of farm households to recombine human, financial, natural and physical capitals are linked to observed economic resilience to land set-aside interventions. The land set-aside intervention known as the Grain for Green Project (GGP), which has been altering livelihoods of farming households in China’s Loess Hills since 1999, is taken as a case study. Household surveys were conducted in three V-shaped valleys and three riparian areas in Yanhe Township in northwestern China in an effort to measure household resilience and explore its’ relationship to forms of capital. A composite index of adaptive strategies that can reorganize livelihood activities under land set-aside intervention into a new economic equilibrium is crafted using an objective weighting scheme based on principal component analysis. Subsequently, a multiple regression model was utilized to examine the relationship between the composite resilience index and various indicators related to human, social, financial, natural and physical capitals. The results reveal the latent structure and internal correlations of adaptive strategies, and present quantitative evidence about the relationship between livelihood capitals and household economic resilience. The analysis shows that household resilience deteriorates when the ratio of GGP land to cultivated farmland goes above a threshold level, and revealed that interventions targeting various forms of capitals can enhance the economic resilience for households to conservation efforts.  相似文献   

16.
ABSTRACT

Capitalist transformations in West New Britain Province, Papua New Guinea, have focused on setting boundaries on land and social relations as an efficient way to generate productive relations. But for the Maututu around Bialla town where the palm oil industry has been established the perception of productivity rests not on establishing boundaries but on exploring horizons. Recent dramatic changes to the economy and demography of this area have introduced moral conflict into Maututu endeavours to generate well-being. Maututu have responded to these conflicts in ways that continue to bring their indigenous morality to bear on the moral strategies pursued by state and capitalist forces.  相似文献   

17.
Oil-palm agriculture is the greatest immediate threat to biodiversity in Southeast Asia. Despite the efforts of environmentalists, oil palm continues to expand across the tropics. Those concerned about the impacts of oil palm on biodiversity must face some harsh social, economic, and ecological realities: (i) oil palm has been a very profitable crop; (ii) palm oil is used in so many products that simple, direct actions, such as boycotts, are unlikely to succeed; (iii) there is currently insufficient demand for certified sustainable palm oil and inadequate political clout from environmental groups in two of the biggest markets for palm oil—China and India—to slow the rate of forest conversion; and (iv) oil-palm agriculture has improved the lives of poor rural communities in Southeast Asia (although it has also disenfranchised some indigenous communities). To address the threats posed by oil-palm agriculture to biodiversity, environmentalists must change the behavior of the palm oil business through: (i) regulations to curb undesirable activities (e.g., a ban on converting forests to oil palm); (ii) financial incentives to promote desirable behavior (e.g., production of certified, sustainable oil palm); (iii) financial disincentives designed to discourage undesirable behavior (e.g., consumer pressure on major manufacturers and retailers to use palm oil that does not come from plantations created at the expense of forests); and (iv) the promotion of alternative, more biodiversity-friendly uses of forested land that might otherwise be converted to oil palm. There is no single best approach for dealing with the oil-palm crisis in Southeast Asia; a mixture of regulations, incentives, and disincentives targeted at all sectors of the oil-palm industry is necessary to protect the region’s rapidly disappearing forests.  相似文献   

18.
Amid discussions of an agricultural crisis and the failure of largescale, mechanized, capitalintensive development schemes in Nigeria, the Kofyar of Plateau State provide a case study of farmers spontaneously expanding food crop production for the market, using indigenous lowenergy technology. Temporary, followed by permanent, migration from the Jos Plateau homeland to frontier settlements on the fertile Benue plains has been accompanied by a change from initial shifting cultivation in forest clearings to permanent, intensively tilled and fertilized homestead fields. Labor is organized primarily in households that have grown in size and complexity. Cooperative and exchange work groups are also important for meeting seasonal bottlenecks and providing the careful, disciplined cultivation that intensive agriculture requires. Kofyar now devote up to 50% of their labor to cash crops, and they purchase considerable quantities of manufactured goods and medical services. Their uncoerced adaptation to an environment of new land resources and market incentives suggests both the advantages of indigenous development with a minimum of state control or interference and the limitations of a conventional dependency theory perspective.  相似文献   

19.
Policy makers across the tropics propose that carbon finance could provide incentives for forest frontier communities to transition away from swidden agriculture (slash‐and‐burn or shifting cultivation) to other systems that potentially reduce emissions and/or increase carbon sequestration. However, there is little certainty regarding the carbon outcomes of many key land‐use transitions at the center of current policy debates. Our meta‐analysis of over 250 studies reporting above‐ and below‐ground carbon estimates for different land‐use types indicates great uncertainty in the net total ecosystem carbon changes that can be expected from many transitions, including the replacement of various types of swidden agriculture with oil palm, rubber, or some other types of agroforestry systems. These transitions are underway throughout Southeast Asia, and are at the heart of REDD+ debates. Exceptions of unambiguous carbon outcomes are the abandonment of any type of agriculture to allow forest regeneration (a certain positive carbon outcome) and expansion of agriculture into mature forest (a certain negative carbon outcome). With respect to swiddening, our meta‐analysis supports a reassessment of policies that encourage land‐cover conversion away from these [especially long‐fallow] systems to other more cash‐crop‐oriented systems producing ambiguous carbon stock changes – including oil palm and rubber. In some instances, lengthening fallow periods of an existing swidden system may produce substantial carbon benefits, as would conversion from intensely cultivated lands to high‐biomass plantations and some other types of agroforestry. More field studies are needed to provide better data of above‐ and below‐ground carbon stocks before informed recommendations or policy decisions can be made regarding which land‐use regimes optimize or increase carbon sequestration. As some transitions may negatively impact other ecosystem services, food security, and local livelihoods, the entire carbon and noncarbon benefit stream should also be taken into account before prescribing transitions with ambiguous carbon benefits.  相似文献   

20.
The biodiversity and climate consequences of oil palm (Elaeis guineensis) expansion across South East Asia have received considerable attention. The human side of the issue, highlighted with reports of negative livelihood outcomes and rights abuses by oil palm companies, has also led to controversy. Oil palm related conflicts have been widely documented in Indonesia yet uptake by farmers has also been extensive. An assessment of the livelihood impacts of oil palm development, including sources of conflict, is needed to shed light on the apparent contradiction between these reports and the evident enthusiasm of farmers to join the oil palm craze thereby informing future expansion. We assessed the impact of oil palm development on the economic wellbeing of rural farmers in Indonesia. We found that many smallholders have benefited substantially from the higher returns to land and labour afforded by oil palm but district authorities and smallholder cooperatives play key roles in the realisation of benefits. Conflicts between communities and companies have resulted almost entirely from lack of transparency, the absence of free, prior, and informed consent and unequal benefit sharing, and have been exacerbated by the absence of clear land rights. We make specific recommendations to improve the present situation and foster the establishment of smallholder friendly production regimes. Oil palm expansion in Indonesia is set to continue. If environmental standards can be raised and policy interventions targeted at the broader social impacts of land development this expansion may be achieved to the significant benefit of large numbers of rural smallholders.  相似文献   

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