Agriculture And The Environment Research Articles

Agriculture and the Environment R&D

Agriculture and the Environment R&D

Plant Development and Harvest Yields of Greenhouse Tomatoes in Six Organic Growing Systems

Problems concerning the environmental impact of agriculture have led to a reassessment of the conventional practices used since the 1940s, and a renewed interest by growers in organic farming began during the 1980s. Consumer interest has also increased dramatically, both for health and environmental reasons (Greene, 2000; Lampkin, 1990; Uri, 1999). Since 1996, surveys of natural food wholesalers and retailers indicated that organic produce sales had increased ≈20% yearly (Dimitri and Richman, 2000; Greene, 2001; Greene et al., 2001). Certified organic produce typically commands a higher price than conventionally grown produce. A recent survey of North Carolina-based natural food retailers and wholesalers indicated that buyers were willing to pay up to 25% more for organically grown vegetables (Estes et al., 1999). As a result of all these factors, an increasing number of growers are considering the use of, or are already employing, organic production methods. Barriers to organic certification are particularly high for greenhouse vegetable growers because virtually no technical information is available. Practices used by an experienced greenhouse organic grower to grow plants in soil have been documented (Grubinger, 1999), but specific practices for injecting fertilizer in the drip irrigation lines were not adequately described. Several grower-formulated mixtures for organic transplant production have been described (Smith, 1994), but there is little or no documentation on how to prepare organic mixes for recirculating hydroponic systems or how to add composts to soilless media used for crop production. Compost teas can be used for drip irrigation in certified organic production. However, in a manual describing the use of compost teas, Ingram and Alms (1999) describe work on compost teas as being in its infancy. The beneficial effects of compost teas were demonstrated, but most testing was conducted by trial and error. This is also true of studies using organic composts as ingredients in potting mixes and in many cases, media and waste characteristics were not reported in detail. In Germany, effluent from a fish farming unit was brought into a hydroponic cucumber (Cucumis sativus L.) and tomato greenhouse as a substitute for some of the normal fertilization (Drews and Rennert, 1992). In this study, the amount of fertilizer added to the hydroponic system was reduced by 16% for N, 14% for P, and 12% for K. Although a few examples of the successful use of organic materials in greenhouse vegetable production have been documented, it is hard to extrapolate findings to other crops and media. Broiler litter has been tested as a potting component for lettuce (Lactuca sativa L.) (Flynn et al., 1995). There are also examples where system components were well described. Tyler et al. (1993a, 1993b), Kraus et al. (2000), and Kraus and Warren (2000) conducted a series of studies of the effects of composted poultry litter on growth of containerized nursery crops. These studies described the chemical and physical characteristics of litter when combined with a pine bark substrate. However, as nursery crops grow more slowly than tomato crops, their results cannot be directly applied to a greenhouse tomato production system. Since there are no generally accepted recommendations or guidelines specifically for organic production of greenhouse tomatoes, this study was designed as a systems research project. As such, management practices for each growing season utilized information gathered from the previous growing season(s) to optimize practices for each system. The objectives of this study were to discover methods to produce healthy and productive tomato plants using flowable organic fertilizers, determine formulations for such fertilizers, and develop an organic growing medium that promotes healthy and productive tomato plants. The goal of this research project was to develop a certifiable organic regimen for growing greenhouse tomatoes that would be comparable with those grown conventionally with regard to production methods, as well as nutritional status in leaf tissue, plant development, and harvest yields.

How effective are European agri‐environment schemes in conserving and promoting biodiversity?

Summary Increasing concern over the environmental impact of agriculture in Europe has led to the introduction of agri‐environment schemes. These schemes compensate farmers financially for any loss of income associated with measures that aim to benefit the environment or biodiversity. There are currently agri‐environment schemes in 26 out of 44 European countries. Agri‐environment schemes vary markedly between countries even within the European Union. The main objectives include reducing nutrient and pesticide emissions, protecting biodiversity, restoring landscapes and preventing rural depopulation. In virtually all countries the uptake of schemes is highest in areas of extensive agriculture where biodiversity is still relatively high and lowest in intensively farmed areas where biodiversity is low. Approximately €24·3 billion has been spent on agri‐environment schemes in the European Union (EU) since 1994, an unknown proportion of it on schemes with biodiversity conservation aims. We carried out a comprehensive search for studies that test the effectiveness of agri‐environment schemes in published papers or reports. Only 62 evaluation studies were found originating from just five EU countries and Switzerland (5). Indeed 76% of the studies were from the Netherlands and the United Kingdom, where until now only c. 6% of the EU agri‐environmental budget has been spent. Other studies were from Germany (6), Ireland (3) and Portugal (1). In the majority of studies, the research design was inadequate to assess reliably the effectiveness of the schemes. Thirty‐one percent did not contain a statistical analysis. Where an experimental approach was used, designs were usually weak and biased towards giving a favourable result. The commonest experimental design (37% of the studies) was a comparison of biodiversity in agri‐environment schemes and control areas. However, there is a risk of bias if either farmers or scheme co‐ordinators select the sites for agri‐environment schemes. In such cases the sites are likely to have a higher biodiversity at the outset compared to the controls. This problem may be addressed by collecting baseline data (34% of studies), comparing trends (32%) or changes (26%) in biodiversity between areas with and without schemes or by pairing scheme and control sites that experience similar environmental conditions (16%). Overall, 54% of the examined species (groups) demonstrated increases and 6% decreases in species richness or abundance compared with controls. Seventeen percent showed increases for some species and decreases for other species, while 23% showed no change at all in response to agri‐environment schemes. The response varied between taxa. Of 19 studies examining the response of birds that included a statistical analysis, four showed significant increases in species richness or abundance, two showed decreases and nine showed both increases and decreases. Comparative figures for 20 arthropod studies yielded 11 studies that showed an increase in species richness or abundance, no study showed a decrease and three showed both increases and decreases. Fourteen plant studies yielded six studies that showed increases in species richness or abundance, two showed decreases and no study showed both increases and decreases. Synthesis and applications. The lack of robust evaluation studies does not allow a general judgement of the effectiveness of European agri‐environment schemes. We suggest that in the future, ecological evaluations must become an integral part of any scheme, including the collection of baseline data, the random placement of scheme and control sites in areas with similar initial conditions, and sufficient replication. Results of these studies should be collected and disseminated more widely, in order to identify the approaches and prescriptions that best deliver biodiversity enhancement and value for money from community support.

Organic livestock production systems and appropriate development in relation to public expectations

There has been considerable growth in the number of organic farms, including livestock, in the EU over the last few years. Livestock production, and especially ruminant livestock production, forms an integral part of many organic farms due to its role in nutrient recycling on farms. In 14 out of 16 European countries, livestock products were within the top five organic products. The recent development of organic farming represents the penetration of important aspects of recent major changes in society at large into agriculture. The development can be attributed to increased consumer interest in organic products while, at the same time, farmers are interested in converting to organic production methods, often stimulated by government support or subsidies. It is important that the organic production systems can fulfil the expectation of each of these stakeholders if organic livestock production is to increase further. This is discussed in detail. It is argued that organic livestock production in future will be carried out by farmers who are committed to organic ideals and, therefore, it is important that new livestock systems are developed which comply to a higher degree with these ideals. The consumer’s interest in organic farming seems mainly to be related to care of their own health and the environmental impact of agriculture, but also to considerations of animal welfare. Large regional differences also exist as regards consumers’ priorities. In European countries and the EU support for organic farming is justified as an element in stimulating/regulating the agricultural sector to be more supportive of rural development, diversifying production, and reducing the environmental load of agriculture. The different priorities in different regions in Europe reflect the different concerns as regards agricultural development in the individual regions. In central and Eastern European countries there is also growing interest in organic production methods, mainly because these systems are expected to offer a more profitable and sustainable production system based on low input. So it appears that organic livestock production systems have to reflect different expectations. Livestock rearing should contribute to more balanced overall farm production, food safety (in a broad sense) should be enhanced, and animal welfare should be improved compared to conventional production methods. Also, the systems should support rural development, nature conservation, and the environmental load should be low. The success of the expansion of organic systems will depend on how far these different expectations can be fulfilled without resulting in the premium prices of the products being too high. Research, development, and advisory service have major roles in supporting the development of such a livestock system, which addresses major current societal concerns. There probably is a need for better interaction between mainstream agricultural research and research groups specializing in areas of importance for organic farming.

GM technology: a tool to benefit livestock production in less developed and developed countries

The combined effects of improved varieties, increased fertiliser use and irrigation coupled with increased pesticide use was instrumental in allowing world food production to double in the last 35 years. However, as we enter the 21st century world population is set to increase by a further 1.5 billion by 2020, with the rate of increase being higher in less developed than developed countries. At the same time the rate crop improvement is slowing. In addition the area of land available/appropriate for the production of food and feed resources are at best static and at worst decreasing, often due to wind and water erosion. It has also been estimated that the demand for livestock products will increase dramatically in the next 20 years, with the increase being markedly higher in developing countries (3% per year), where much of the increased demand will be generated from an increasing urban population, than developed countries (1% per year). This projected increase in demand for livestock products will require very significant increased production of cereal grain and sources of oilseeds in a manner ensuring safety for the public and the environment. It will be a major challenge for global food and feed production to decrease the environmental impact of agriculture while maintaining or improving its productivity and sustainability. This paper will discuss how GM technology can contribute a way forward with the aim of combining higher yields, improved food and feed quality, increased competitiveness with environmentally and agriculturally sustainable practices.

The Importance of Natural and Constructed Wetlands in Agriculture and the Environment

The Importance of Natural and Constructed Wetlands in Agriculture and the Environment

Long-term persistence of aluminium-tolerant and sensitive Phalaris lines on acidic soils and associated changes in soil acidity

Persistence of an aluminium (Al)-tolerant phalaris F1 hybrid (Siro 1146 Phalaris aquatica × P.�arundinacea) was compared with that of 3 more Al-sensitive phalaris (P. aquatica L.) lines (cv. Australian and the progenitors of cvv. Sirosa and Sirolan) at 2 sites (Strathbogie and Baddaginnie) in north-eastern Victoria with strongly acidic soils 20 years after sowing. Soil pHCa and extractable aluminium (AlCa) were also measured to 1 m depth under Siro 1146 and annual grass pasture at each site. All grass treatments contained volunteer subclover. Siro 1146 persisted better than the other lines (P<0.05) at Strathbogie where the soil contained high AlCa concentrations down to 50 cm depth. Soils should be sampled and tested to at least this depth to determine their suitability for phalaris. At this site Australian phalaris persisted better than the progenitors of Sirosa and Sirolan (P<0.01), probably because Australian has more spreading ability and tolerance of set stocking than the winter active lines. At Baddaginnie, the soil contained lower concentrations of AlCa below 20 cm depth than at Strathbogie and persistence of the 3 Al sensitive phalaris lines was good despite the lower rainfall. The less drought-tolerant Siro�1146 persisted poorly at Baddaginnie, but had high ground cover due to high lateral spread of the survivors. At Strathbogie, the 10–20 cm layer of soil under Siro 1146 had a higher pHCa and lower AlCa than that under the other 4 phalaris and the annual grass treatments. Soil under Siro 1146 also had higher pHCa and lower AlCa down to 40�cm�depth compared with the annual grass treatment, the differences being significant in the 20–30 cm layer. These differences were reversed at 50–100 cm, but only the effect on Al was significant. Although soils were not sampled at the beginning of the experiment, adequate replication and randomisation of the grass treatments showed that it was statistically improbable for observed final differences to be due to initial soil differences. The final differences may be due to greater amounts of nitrate being taken up from the upper layers by Siro 1146 over its long growing season compared with the annual grasses, leading to greater nitrate leaching from the upper layers and greater nitrate uptake from lower layers under the annuals (i.e. spatial separation of acid generation and consumption processes within the profile). Another possible reason for the greater acidification below 50 cm by the perennial is that its roots may have taken up more cations in this zone. Because of rising concern in some sectors of the public about the off-site, environmental effects of agriculture, the future role of more acid-tolerant phalaris cultivars growing near native vegetation in the high rainfall zone is discussed.

Agriculture and the environment

Agriculture and the environment

N-losses and energy use in a scenario for conversion to organic farming.

The aims of organic farming include the recycling of nutrients and organic matter and the minimisa-tion of the environmental impact of agriculture. Reduced nitrogen (N)-losses and energy (E)-use are therefore fundamental objectives of conversion to organic farming. However, the case is not straightforward, and different scenarios for conversion to organic farming might lead to reduced or increased N-losses and E-use. This paper presents a scenario tool that uses a Geographical Information System in association with models for crop rotations, fertilisation practices, N-losses, and E-uses. The scenario tool has been developed within the multidisciplinary research project Land Use and Landscape Development Illustrated with Scenarios (ARLAS). A pilot scenario was carried out, where predicted changes in N-losses and E-uses following conversion to organic farming in areas with special interests in clean groundwater were compared. The N-surplus and E-use were on average reduced by 10 and 54%, respectively. However, these reductions following the predicted changes in crop rotations, livestock densities, and fertilisation practices were not large enough to ensure a statistically significant reduction at the 95% level. We therefore recommend further research in how conversion to organic farming or other changes in the agricultural practice might help to reduce N-surpluses and E-uses. In that context, the presented scenario tool would be useful.

Agriculture and the Environment: Minerals, Manure and Measures. F. B. de Walle , J. Sevenster

Previous articleNext article No AccessNew Biological BooksAgriculture and the Environment: Minerals, Manure and Measures. F. B. de Walle , J. Sevenster D. A. OudendagD. A. Oudendag Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The Quarterly Review of Biology Volume 75, Number 3Sep., 2000 Published in association with Stony Brook University Article DOIhttps://doi.org/10.1086/393576 Copyright 2000 The University of ChicagoPDF download Crossref reports no articles citing this article.

Method to monitor and quantify the environmental impact of European agriculture: conceptual outline

European policy is currently aiming at reducing the environmental impact of agriculture. To evaluate the effect of the measures, a Europe-wide method is needed that provides standardized information for all countries. This paper presents the outline of a method intended to determine where and to what extent the environmental impact of agriculture has changed. It consists of three procedures: general change detection, determination of agricultural presence in the region, and change identification. The method offers standardized information on the location and extent of changes in environmental impact caused by agriculture. Changed regions can be located shortly after the growing season, which enables the adjustment of policy to the actual situation. Hence, it will provide a useful tool to evaluate and formulate policy measures intended to influence the environmental impact of agriculture.

Soil tillage for crop production and for protection of soil and environmental quality: a Scandinavian viewpoint

Based on experience from 35 years of tillage research in Sweden, future development of soil tillage is discussed and some research problems are identified. Tillage and seeding methods must be more carefully adapted to conditions at individual sites and occasions. Low-pressure typres, better weed control and improved seed coulters favour the increased use of reduced tillage. In order to diminish the impact of agriculture on the environment, it is necessary to develop methods for establishment of crops in the early spring or immediately after harvest, even in soils with large amounts of crop residues or high moisture content. The roles of tillage methods, and of soil compaction and structure on environmental impact of agriculture must be investigated. World food production must increase, since the world population is rapidly increasing. Therefore, it is necessary to develop improved crop production systems, including crop establishment systems, which favour efficient use of basic crop growth factors, while protecting or increasing soil productivity. Compaction, decreased organic matter content, and erosion are important long-term threats to soil productivity.

Agriculture and the environment

Agriculture and the environment

Incorporating agroecology into the conventional agricultural curriculum

AbstractAgroecology is the development and application of ecological theory to the management of agricultural systems, according to the specific land and other resources available. Beyond the biological and climatic dimensions of agriculture and ecology, there is growing appreciation of the influence of social, economic, and political factors on the structure and success of farming systems. This broader field is becoming known as “agroecology and sustainable development.” Expansion of the conventional curriculum to include integrative themes is essential because of the need for students to appreciate a whole farm focus for analysis, to understand the impact of socio-economic factors, and to further develop their abilities to link people and environment. Two courses are proposed and described in detail “Biology of Agroecosystems” includes study of system structure and function, cycles and interactions among components, system development and performance, and the importance of resource conservation and use. “Agroecology and Sustainable Agricultural Development” includes a survey of systems around the world, an evaluation of resources and their use, the environmental impact of agriculture, the relationships between society and agriculture, the applications of agroecology to rural development, and some projections of alternative future strategies for food production. Future agricultural professionals need to understand how improvement of agroecosystems is closely linked to economic, cultural, and political systems, and how they are both enhanced and constrained by factors beyond biology and climate.

Selenium in Agriculture and the Environment

Selenium in Agriculture and the Environment

Role of Agriculture in a City-State Economy: The Case of Singapore

The paper shows that agriculture can play a new role in city-state economies such as Singapore. Although high-technology farming will make more effective contributions in future, the non-monetary benefits of agriculture may remain paramount in such economies. It is emphasized that the environmental effects of agriculture should be measured by using the newly developed techniques in order to make a proper evalua tion of their economic role.

Agriculture and the Environment. ITE Symposium No. 13.

Agriculture and the Environment. ITE Symposium No. 13.

The Environmental Impact of Agriculture in Ethiopia

The basis of the physico-social pattern in Ethiopia, indicated above, may be summarized as:(a) The main features of the country are formed by volcanic activity;(b) There exist a lot of fragmented highlands with a great range of altitude, climate, and vegetation;(c) The content of organic matter in the soils is very low on the eroded lands, greatly limiting their ability to retain water;(d) There exist a wide variety of cultural patterns and numerous spoken languages;(e) There are very severe erosion hazards and continuous deforestation activities;(f) There is a custom of uncontrolled grazing, and livestock are not limited according to the carrying capacity of the land;(g) There are constraints in the distribution and quality of water that is available for domestic supplies, livestock, and crops;(h) From ancient times there has been no substantial improvement in farming tools and implements;(i) There is little government investment in development work in general;(j) The importance of a conservation programme for a wide range of natural resources is not felt/realized by the government;(k) There is no emphasis on erosion control and forestry management—even by the regional development projects of the minimum and maximum package projects financed by the World Bank and other bilateral international cooperations;(l) There are big constraints in matters of education and agricultural extension services; and(m) The mountainous terrain and deep gorges have made communication difficult and expensive.As a result of the above, the overall development network does not at present provide an adequate access to support a productive and continuous agriculture.

Food, Agriculture and the Environment. Environment and Man, Volume Two. John Lenihan , William W. Fletcher

<i>Food, Agriculture and the Environment. Environment and Man, Volume Two</i>. John Lenihan , William W. Fletcher

Insecticides in health, agriculture and the environment.

Insecticides in health, agriculture and the environment.