Simultaneous adoption of integrated soil fertility management technologies in the Chinyanja Triangle,Southern Africa

Empirical scientific evidence indicates that there is still room for increasing food production by improving land productivity. This study aimed at identifying the key determinants that govern farmers’ decisions to adopt multiple components of integrated soil fertility management (ISFM) in a maize mixed cropping system of the Chinyanja Triangle, Southern Africa. Revealed preferences of ISFM components were collected from 320 randomly selected households and multivariate probit (MVP) model was used to analyse the simultaneous effects on adoption based on biophysical plot and household‐level socioeconomic attributes. The results show that farmers’ choices of a set of ISFM components are determined by a mix of factors that address the trade‐offs and synergies among them. Non‐farm income, moderate land quality perception, and education influence simultaneous technology adoption, while gender and crop loss increase the likelihood of farmers’ decisions to adopt independent options. Having other sources of income supports co‐adoption of inorganic fertilizer, residue incorporation, and crop rotation. Input/output market access, access to information, financial sources, and climate variability also play pivotal role in technology adoption. These results indicate that resource availability, learning costs, finances, and risk aversion need to be considered when designing and promoting ISFM technologies as a package.     

贵州普定后寨河流域岩溶生态脆弱性的模糊综合评价

本文介绍了基于模糊数学理论的岩溶生态脆弱性评价方法，选取了平均坡度、森林覆盖率、石山裸露、耕地面积、水土流失、人口密度、．人均耕地、人均粮食、人均收入9个主要因素作为评价因素，并以贵州省普定县后寨河流域为例进行了具体计算与分析。评判结果表明：该研究区生态脆弱形势较为严重，在13个典型喀斯特村中有7个属于强度脆弱或极强度脆弱区，2个属于中度脆弱，属于轻度脆弱的有4个，因而需大力加强生态环境保护和重建工作。     

Occurrence and fate of the phytotoxin juglone in alley soils under black walnut trees

Juglone (5-hydroxy-1,4-napthoquinone) is a chemical released by walnut trees, which can be toxic at various levels to several plant species. A balance among competing source and sink mechanisms and rates will ultimately determine whether juglone is capable of attaining sufficient levels to be allelopathic to intercrops in a walnut tree agroforestry system. In this study, juglone's release, accumulation, and decline in soil are explored using data from soil beneath a black walnut tree (Juglans nigra L) alley cropping system, greenhouse pot studies, and laboratory sorption/degradation studies. Juglone pore water concentrations estimated from extracts of surficial soil from beneath the alley cropping system exceeded the lowest solution culture toxicity levels reported for some plants of 10(-7) M, but did not exceed the inhibition threshold reported for typical intercrops such as maize and soybeans 10(-5) M. Further assessment of the likely persistence of juglone in soils indicated that juglone is both microbially and abiotically degraded, and that it will be particularly short-lived in soils supporting microbial activity. However, walnut seedlings planted in sand-filled pots clearly showed that juglone is released in measurable quantities to the soil's rhizosphere. Therefore, juglone accumulation in low fertility soils is plausible, and may still be worthy of consideration in management of alley agroforestry systems.     

Determinants of Farmers’ Adoption of Improved Soil Conservation Technology in a Middle Mountain Watershed of Central Nepal

This study explores different socio-economic and institutional factors influencing the adoption of improved soil conservation technology (ISCT) on Bari land (Rainfed outward sloping terraces) in the Middle Mountain region of Central Nepal. Structured questionnaire survey and focus group discussion methods were applied to collect the necessary information from farm households. The logistic regression model predicted seven factors influencing the adoption of improved soil conservation technology in the study area including years of schooling of the household head, caste of the respondent, land holding size of the Bari land, cash crop vegetable farming, family member occupation in off farm sector, membership of the Conservation and Development Groups, and use of credit. The study showed that technology dissemination through multi-sectoral type community based local groups is a good option to enhance the adoption of improved soil conservation technology in the Middle Mountain farming systems in Nepal. Planners and policy makers should formulate appropriate policies and programs considering the farmers' interest, capacity, and limitation in promoting improved soil conservation technology for greater acceptance and adoption by the farmers.     

Locus of control and farmer orientation: Effects on conservation adoption

Farmers in a southwestern Ontario watershed were surveyed to determine factors influencing their attitudes towards adoption of soil conservation practices. The majority of farmers in the watershed were internally motivated which indicates they believe that their own actions determine their successes and failures. Most respondents were also environmentally oriented. However, although many farmers in the study area have adopted crop rotations and cross-slope tillage, the adoption rate of conservation tillage is low. The survey suggests that the low adoption rate may be more a function of perceived economic risk associated with the tillage practice than lack of farmer motivation.     

Poverty and biodiversity in rural areas based on two investigations in Pujiang County,China

This study presents an integrated framework for the analysis of options of agricultural development and natural resource management at the ecosystem level. Pujiang County in Zhejiang Province, China, is used as a case-study area. The IMGLP model is applied to maximize regional agricultural economic surplus and labor market conditions in Pujiang. The consequences of four poverty reduction strategies (intensification of production, diversification toward livestock production, land expansion, and exit from agriculture) are determined for a set of regional poverty and biodiversity indicators. Diversification seems to be the most promising poverty reduction strategy, but requires an efficient use of animal manure in cropping systems to avoid environmental problems. Improved nutrient management in cropping systems is effective in reducing the regional nitrogen surplus, but less effective in increasing per capita income. The exit strategy is beneficial for reducing poverty and achieving biodiversity, but may have important social consequences that are not addressed in this study. Further reduction of rural poverty is hampered by labor constraints during the harvesting period for high-value crops such as vegetables and fruits. These constraints can be overcome by intensive research and development in the field of agricultural mechanization.     

Soil and water conservation method adoption in a highly erosive watershed: the case of Southwest Oklahoma's Fort Cobb watershed

A major source of pollution in agricultural landscapes is surface runoff and non-point source pollution generated from agricultural production practices. In-stream, stream bank and riparian conservation/management practices can be implemented to reduce sediment loading solely or in conjunction with upland practices. Survey results from producers in the Fort Cobb Reservoir watershed, a highly erosive watershed in southwest Oklahoma with a history of state and federal conservation programs, provide information required for improving understanding of operators’ likelihood of adoption. Two models of soil and water conservation were estimated, a logit model of likelihood of enrollment and a Poisson model of the total number of practices adopted. Results reinforced previous findings that attitudes, gender and education influence conservation program enrollment. Farming experience, gender and attitudes towards conservation increased the total number of practices adopted.     

Using pruning residues as mulch: analysis of its adoption and process of diffusion in Southern Spain olive orchards

This paper analyses both the processes of adoption and diffusion of the practice of using the chopped residues of pruning as mulch in the olive orchards of the Southern Spanish province of Granada, one of the major olive-producing areas in the world. Many olive groves in the area are located on steep areas where the risk of soil erosion is high. A majority of farmers have adopted no tillage, as an alternative to traditional tillage, combined with either vegetation soil covers or, more frequently, using the chopped pruning residues as mulch. The data used comes from a survey carried out in 2005 to 215 olive farmers. From farmers' responses we estimate a binomial probit model to identify some socio-economic and institutional factors related to the decision to use the practice of mulching on a regular basis. We also estimate several diffusion models that describe the spatial and temporal spread of mulching among farmers. Our results show that mulching using the pruning residues is adopted by 43% of the surveyed farmers. The diffusion process of this practice has been very intense since the middle nineties, and seems to have been based on the interactions among farmers in the area of study rather than in other external source of information. Some of the relevant identified factors that affect the probability of adoption of this practice are farmer's experience, the level of soil degradation in the farm or the continuity of farming by some relative.     

Trends in the intensity of copper use in Japan since 1960

Between 1960 and 2000, Japan's real GDP grew 620%. However, its consumption of copper increased only 345%, thanks to a 38% decline in the country's intensity of copper use. In light of concerns today over the possible impact of future economic development in China, India, and other developing countries on the long-run availability of mineral resources, this study proposes to explore the causes for this dramatic decline in the Japanese intensity of copper use.For some time, we have known that the intensity of metal use within a country depends on its level of economic development, usually measured by per capita income, as well as on technological change, long-run price trends, and other factors whose influence varies, more or less, with time. This study finds that rising per capita income has increased the intensity of copper use in Japan over the entire period examined. Moreover, this positive effect is expected to continue until per capita income—$44,830 in 2000—reaches $53,000. Thereafter, further advances will tend to reduce the intensity of copper use. Conversely, new copper-saving technologies and other time-related variables have on average reduced the intensity of copper use by 2.9% a year, an amount sufficient not only to offset the positive effects of growing per capita income but also to reduce intensity of use by 38%.     

Issues in the Management of the Environment and Natural Resources in Bangladesh

Bangladesh is one of the most densely populated countries in the world with a very low per capita income. The increasing poverty and instability in the political front led to degradation of the environment and natural resources in the country. The present article reviews the current use of natural resources in Bangladesh and the emerging issues in sustainable management of those scarce resources. The paper shows that developments in one sector have adversely affected resources in related sectors and calls for an integrated approach to management of the environment and natural resources in a sustainable manner. The development of strong institutional mechanisms is necessary to facilitate the sustainable management of resources and to prevent further deterioration of the environment.     

Long-term dynamics in land resource use and the driving forces in the Beressa watershed, highlands of Ethiopia

Land degradation in the Ethiopian highlands is considered to be one of the major problems threatening agricultural development and food security in the country. However, knowledge about the forces driving the long-term dynamics in land resources use is limited. This research integrates biophysical information with socio-economic processes and policy changes to examine the dynamics of land resource use and farmers' livelihoods in the Beressa watershed for over 40 years during the second half of the 20th century. It was found that there have been substantial dynamics in land resource use in the area. The natural vegetation cover has been extensively cleared, although most of the cleared areas have since been replaced with plantations. Grazing land has expanded remarkably at the expense of cropland and bare land. However, the expansion of cropland was minimal over the 43-year period despite a quadrupling of the population density. Yields have not increased to compensate for the reduction in per capita cropland, and the soil quality appears to be not that good. Though the farmers perceived it otherwise, the long-term rainfall pattern has improved. In response to soil degradation, water shortage, socio-economic and policy changes, farmers have tended to gradually change from annual cropping to tree planting and livestock production to cope with the problems of soil degradation, water scarcity and smaller farms. Income diversification through the sale of wood and cattle dung is becoming a major livelihood strategy. Apparently, however, little attention has been paid to investments in soil and water conservation (SWC) and local soil fertility amendments. In particular, increased erosion and related high nutrient losses in sediments, as well as the removal of potentially available soil nutrients through the sale of manure threatens to damage agricultural sustainability in the area.     

上海文化产业及贸易发展影响因素的灰色关联度分析

在经济全球化浪潮的推动下，文化影响力日益加大，文化产业成为各国竞相争抢的战略高地。文化贸易作为一种新的贸易形态实现了迅猛增长，而国与国竞争的焦点在于主要节点城市实力的较量。采用灰色关联方法，从经济发展、产业规模、市场需求和科研创新四个方面选取14个指标，对上海文化产业及贸易发展的影响因素进行了实证分析。结果表明，城乡居民家庭人均可支配收入等因素对上海文化产业发展有着重要的关联影响，而人均生产总值和互联网用户普及率等因素对上海文化贸易有着重要的影响，但科技成果与文化产业及贸易的关联度均较小，尤其是外贸依存度的关联影响不显著。     

Evaluating the Environmental Performance of Urban Parks in Mediterranean Cities: An Example from the Barcelona Metropolitan Region

In a context of increasing urban sprawl and water scarcity common to other Mediterranean cities, this article focuses on the urban parks in the Region of Barcelona (Catalonia, Spain) to examine how these parks are distributed in this region and to assess whether their design and management follow criteria adapted to Mediterranean environmental conditions, especially in what concerns water use. In order to evaluate the environmental performance of these parks, we selected four factors possibly influencing the adoption of park management practices at the local scale: urban density, population size of the municipality, municipal income per capita, and political orientation of the city council. After determining the location and area of urban parks in the region, we correlated these four explanatory factors with several management tasks extracted from two different samples of parks (one of 315 parks and another of 125 parks) and a survey of 86 city councils. Results show that, in general, urban parks were more frequent in large, dense, and left/green municipalities but that environmentally sound practices were more common in small and low-density municipalities. We conclude that changes in certain practices (especially the substitution of high water demanding species) could improve significantly the environmental performance of public spaces in large urban areas with Mediterranean climates. Our observations may be pertinent for other cities interested in the provision of environmental public goods such as parks that necessitate water for irrigation.     

Characterizing land-use diversity in village landscapes for sustainable mountain development: a case study from Indian Himalaya

This study aimed to analyze the ecological, socio-economic and policy implications of land-use diversity in a traditional village landscape (900–1,000 m amsl.) in the Garhwal region of Indian Himalaya. The village landscape was differentiated into three major land-use types viz., forests, settled agriculture and shifting agriculture. Settled agriculture was further differentiated into four agroecosystem types viz., homegarden system (HGS), rainfed agroforestry system (RAS), rainfed crop system (RCS) and irrigated crop system (ICS), and shifting agriculture system (SAS) was differentiated into different stages of a 4-year long cropping phase and a 7-year long fallow phase, and forests into Community Forests (CF) and Reserve Forests (RF). HGS is the most productive agroecosystem, with soil organic carbon and nutrient concentrations significantly higher than all other forest/agricultural land-uses. Farmers capitalize upon crop diversity to cope with the risks and uncertainties of a monsoon climate and spatial variability in ecological factors influencing productivity. The SAS, a land-use adopted as a means of acquiring inheritable rights over larger land holdings provided in the policies during the 1890s, is less efficient in terms of land productivity than the traditional RAS and HGS but is maintained for its high labour productivity coupled with availability of high-quality fuelwood from fallow vegetation. Dominance of fodder trees in the RAS seems to derive from policies causing shortage of fodder available from forests. Cultural norms have favoured equity by allowing hiring of labour only from within the village community and income from non-timber forest products only to the weaker section of the society. Conversion of rainfed to irrigated cropping, a change facilitated by the government, improves agricultural productivity but also increases pressure on forests due to higher rates of farmyard manure input to the irrigated crops. Existing forest management systems are not effective in maintenance of a large basal area in forests together with high levels of species richness, soil fertility and resistance to invasive alien species Lantana camara. Farmers have to spend huge amount of labour and time in producing manure, managing livestock and other subsidiary farm activities. Interlinkages among agriculture, forests and rural economy suggest a need of replacing the present policies of treating agricultural development, forest conservation and economic development as independent sectors by an integrated sustainable development policy. The policy should promote technological and institutional innovations enabling parallel improvements in agricultural productivity and functions of forest ecosystems.     

Nitrogen and phosphorus exports from high rainfall zone cropping in Australia: issues and opportunities for research

Cropping is one of the many industries contributing to the excessive loading of nitrogen (N) and phosphorus (P) to rivers and lakes in Australia. Nitrogen and P exports from cropping systems have not been systematically investigated to the same extent as those from other agricultural sectors, such as dairy pastures. Therefore, this review relies heavily on information derived from agronomy and other fundamental studies on soil-nutrient interactions to determine the potential for nutrient export from high rainfall zone (HRZ) cropping. There is a great deal of variation in environmental and management strategies across cropping in the HRZ, which suggests that nutrient exports could occur under a range of scenarios. The potential for exports is therefore discussed within a conceptual framework of nutrient sources, mechanisms for mobilization, and transport pathways in HRZ cropping. Transport refers to nutrient movement by flowing water after it has been mobilized, and export refers to the transfer of nutrients from one landscape compartment (e.g., a soil) to another (e.g., a stream or lake). The transport of nutrients from HRZ cropping can occur through surface and/or subsurface pathways depending on factors such as landform and infiltration and nutrient sorption characteristics of the soil profile. Surface pathways are likely to be more significant for phosphorus. For N, subsurface movement is likely to be as significant as surface movement because nitrates are generally not bound by most soils. Information about mechanisms of nutrient mobilization is essential for developing management strategies to control nutrient exports from HRZ cropping.     

Changing Farmers' Land Management Practices in the Hills of Nepal

This paper sheds light on changing farmers' land management practices in two mountain watersheds, with and without external assistance, in the western hills of Nepal. Information used in the analysis were obtained through a survey of 300 households, group discussion, key informant interviews, and field observation conducted during April–September 1999. Confronted with ever-decreasing landholding size due to a steadily growing population and scarcity of nonfarming employment opportunities, farmers in both watersheds have increasingly adopted assorted types of structural and biological measures to control soil erosion, landslides, gully expansion, and soil nutrient loss to maintain or even enhance land productivity. Adoption of gully control measures, construction of the retention walls, alley cropping, use of vegetative measures for landslide control, mulching, and use of green manure and chemical fertilizers are found significantly high in the project area due to the provision of technical and financial support, whereas composting is found significantly high in the nonproject area. Different from the traditionally held beliefs, population pressure on a finite land resource has brought positive change in land management. However, the experience from both watersheds indicates that there is limit to the extent that resource poor farmers can respond to land degradation without any external assistance. Required is the arrangement for appropriate polices and support services and facilities enabling farmers to adopt locationally suitable and economically attractive land management technologies.     

Spatiotemporal Variation of Karst Ecosystem Service Values and Its Correlation with Environmental Factors in Northwest Guangxi,China

In this investigation we analyzed the spatiotemporal variation of ecosystem service values (ESVs) and its correlation with numerous environmental factors (EFs) for the karst region of Northwest Guangxi, China, from 1985 to 2005 using remote sensing, geographic information systems (GIS) and statistical techniques. The results indicate that historically ESVs for this karst region decreased from 1985 (109.652 billion Yuan) to 1990 (88.789 billion Yuan) and then increased at the turn of the twenty-first century. However, the ESVs in both 2000 (103.384 billion Yuan) and 2005 (106.257 billion Yuan) never achieved the level recorded in 1985. The total of nutrient cycling, organic production and gas regulation combined were 72.69, 64.57, 70.18 and 72.10% of ESVs in 1985, 1990, 2000 and 2005, respectively. In contrast, the ESVs of water conservation, soil reservation, recreation and culture were determined to be relatively low contributing only 17.44, 23.82, 19.26 and 24.76% of total ESVs, respectively, during these four years. With regards to the spatial distribution of ESVs, larger values were recorded in the west and smaller ones recorded in the east. The most significant factors that were deemed to influence ESVs are annual rainfall, per capita cropland, slope and vegetation coverage. Annual rainfall and slope exert a negative force, whereas per capita cropland and vegetation coverage exert a positive force on ESVs. The results of the study would suggest that ecosystem conditions of this important karst region have been improved as the result of the implementation of rocky desertification control policies.     

Exploring constraints and incentives for the adoption of agroforestry practices on degraded cropland in Uzbekistan

Agroforestry is often an economically viable land-use option for the environmental rehabilitation of salinized cropping areas in irrigated drylands, but afforestation initiative at the farm level is subject to various socio-political constraints. We analyzed the factors that affect farmer decisions with respect to the agroforestry adoption using an ex ante approach through Ethnographic Decision Tree Modeling (EDTM). Constraints on agroforestry adoption were identified via a review of legal documents, focus-group discussions, and a farm survey in northwest Uzbekistan. The findings highlighted the importance of farmer perceptions of risk with respect to decision making surrounding the adoption of alternative land uses. The EDTM analysis allowed determining those policy incentives for afforestation that could directly influence the decision-making process of potential participants. In particular, there is a need for increased land-use flexibility, improved land tenure and tree plantation proprietorship security, increased awareness raising and training in agroforestry practices, and greater institutional support.     

Assessing alternatives for mitigating net greenhouse gas emissions and increasing yields from rice production in China over the next twenty years

Assessments of the efficacy of mitigation of greenhouse gas (GHG) emissions from paddy rice systems have typically been analyzed based on field studies. Extrapolation of the mitigation potential of alternative management practices from field studies to a national scale may be enhanced by spatially explicit process models, like the DeNitrification and DeComposition (DNDC) model. Our objective was to analyze the impacts of mitigation alternatives, management of water, fertilizer, and rice straw, on net GHG emissions (carbon dioxide, methane, and nitrous oxide fluxes), yields, and water use. After constructing a GIS database of soil, climate, rice cropping area and systems, and management practices, we ran DNDC with 21-yr alternative management schemes for each of the approximately 2500 counties in China. Results indicate that, despite large-scale adoption of midseason drainage, there is still large potential for additional methane reductions from Chinese rice paddies of 20 to 60% over 2000-2020. However, changes in management for reducing CH4 emissions simultaneously affect soil carbon dynamics as well as N2O emissions and can thereby reorder the ranking of technical mitigation effectiveness. The order of net GHG emissions reduction effectiveness found here is upland rice > shallow flooding > ammonium sulfate > midseason drainage > off-season straw > slow-release fertilizer > continuous flooding. Most of the management alternatives produced yields comparable to the baseline; however, continuous flooding and upland rice significantly reduced yields. Water management strategies appear to be the most technically promising GHG mitigation alternatives, with shallow flooding providing additional benefits of both water conservation and increased yields.     

Environmental impacts of modern agricultural technology diffusion in Bangladesh: an analysis of farmers' perceptions and their determinants

Farmers' perception of the environmental impacts of modern agricultural technology diffusion and factors determining such awareness were examined using survey data from 21 villages in three agro-ecological regions of Bangladesh. Results reveal that farmers are well aware of the adverse environmental impacts of modern agricultural technology, although their awareness remains confined within visible impacts such as soil fertility, fish catches, and health effects. Their perception of intangible impacts such as, toxicity in water and soils is weak. Level and duration of modern agricultural technology adoption directly influence awareness of its adverse effects. Education and extension contacts also play an important role in raising awareness. Awareness is higher among farmers in developed regions, fertile locations and those with access to off-farm income sources. Promotion of education and strengthening extension services will boost farmers' environmental awareness. Infrastructure development and measures to replenish depleting soil fertility will also play a positive role in raising awareness.