http://library.um.ac.id/free-contents/downloadpdf.php/buku/focus-groups-as-qualitative-research-by-morgan-david-l-11476.pdf

Focus groups as qualitative research / by Morgan, David L.

Agroforestry systems are believed to provide a number of ecosystem services; however, until recently evidence in the agroforestry literature supporting these perceived benefits has been lacking. This special issue brings together a series of papers from around the globe to address recent findings on the ecosystem services and environmental benefits provided by agroforestry. As prelude to the special issue, this paper examines four major ecosystem services and environmental benefits of agroforestry: (1) carbon sequestration, (2) biodiversity conservation, (3) soil enrichment and (4) air and water quality. Past and present evidence clearly indicates that agroforestry, as part of a multifunctional working landscape, can be a viable land-use option that, in addition to alleviating poverty, offers a number of ecosystem services and environmental benefits. This realization should help promote agroforestry and its role as an integral part of a multifunctional working landscape the world over.

Agroforestry for ecosystem services and environmental benefits: an overview

Although trees have responded to global warming in the past - to temperatures higher than they are now - the rate of change predicted in the 21st century is likely to be unprecedented. Greenhouse gas emissions could cause a 3-6°C increase in mean land surface temperature at high and temperate latitudes. Despite this, few experiments have isolated the effects of temperature for this scenario on trees and forests. This review focuses on tree and forest responses at boreal and temperate latitudes, ranging from the cellular to the ecosystem level. Adaptation to varying temperatures revolves around the trade-off between utilizing the full growing season and minimizing frost damage through proper timing of hardening in autumn and dehardening in spring. But the evolutionary change in these traits must be sufficiently rapid to compensate for the temperature changes. Many species have a positive response to increased temperature - but how close are we to the optima? Management is critical for a positive response of forest growth to a warmer climate, and selection of the best species for the new conditions will be of vital importance. Contents Summary 369 I. Introduction 370 II. Photosynthesis and respiration 370 III. Soil organic matter decomposition and mineralization 373 IV. Phenology and frost hardiness 376 V. Whole tree experimental responses to warming 380 VI. Changes in species distribution at warmer temperatures 381 VII. Adaptation and evolution 383 VIII. Ecosystem level responses to warming 387 Acknowledgements 390 References 390 Appendix I. Temperature response functions 399.

https://nph.onlinelibrary.wiley.com/doi/pdf/10.1046/j.1469-8137.2001.00057.x

Tree and forest functioning in response to global warming

We review the research literature and summarize the major processes by which riparian vegetation influences chemical water quality in streams, as well as how these processes vary among vegetation types, and discuss how these processes respond to removal and restoration of riparian vegetation and thereby determine the timing and level of response in stream water quality. Our emphasis is on the role that riparian vegetation plays in protecting streams from nonpoint source pollutants and in improving the quality of degraded stream water. Riparian vegetation influences stream water chemistry through diverse processes including direct chemi- cal uptake and indirect influences such as by supply of organic matter to soils and channels, modification of water movement, and stabilization of soil. Some processes are more strongly expressed under certain site condi- tions, such as denitrification where groundwater is shallow, and by certain kinds of vegetation, such as channel stabilization by large wood and nutrient uptake by faster-growing species. Whether stream chemistry can be managed effectively through deliberate selection and management of vegetation type, however, remains uncer- tain because few studies have been conducted on broad suites of processes that may include compensating or reinforcing interactions. Scant research has focused directly on the response of stream water chemistry to the loss of riparian vegetation or its restoration. Our analysis suggests that the level and time frame of a response to restoration depends strongly on the degree and time frame of vegetation loss. Legacy effects of past vegetation can continue to influence water quality for many years or decades and control the potential level and timing of water quality improvement after vegetation is restored. Through the collective action of many processes, vegeta- tion exerts substantial influence over the well-documented effect that riparian zones have on stream water qual- ity. However, the degree to which stream water quality can be managed through the management of riparian vegetation remains to be clarified. An understanding of the underlying processes is important for effectively using vegetation condition as an indicator of water quality protection and for accurately gauging prospects for water quality improvement through restoration of permanent vegetation. (KEY TERMS: assessment; biogeochemistry; buffers; legacy effects; nonpoint source pollution; resilience; resto- ration; rivers ⁄streams; soils; watershed management.)

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The Role of Riparian Vegetation in Protecting and Improving Chemical Water Quality in Streams

The Measurement of Environmental and Resource Values

Intensive agriculture can result in increased runoff of sediment and agricultural chemicals that pollute streams. Consensus is emerging that, despite our best efforts, it is unlikely that significant reductions in nutrient loading to surface waters will be achieved through traditional, in-field management alone. Riparian forest buffers can play an important role in the movement of water and NPS (non-point source) pollutants to surface water bodies and ground water. Riparian buffers are linear in nature and because of their position in the landscape provide effective connections between the upland and aquatic ecosystems. Present designs tend to use one model with a zone of unmanaged trees nearest the stream followed by a zone of managed trees with a zone of grasses adjacent to the crop field. Numerous variations of that design using trees, shrubs, native grasses and forbs or nonnative cool-season grasses may provide better function for riparian forest buffers in specific settings. Properly designed riparian buffers have been shown to effectively reduce surface NPS pollutant movement to streams and under the right geological riparian setting can also remove them from the groundwater. Flexibility in design can also be used to produce various market and nonmarket goods. Design flexibility should become more widely practiced in the application of this agroforestry practice.

/pdf/riparian-forest-buffers-in-agroecosystems-lessons-learned-3bhlxnndnr.pdf

Riparian forest buffers in agroecosystems - lessons learned from the Bear Creek Watershed, central Iowa, USA

Recent reports clearly indicate that odor emitted from concentrated livestock production facilities in the Midwest of the US is a significant social problem that negatively impacts rural and state economies, human health, and the quality of rural life. A potential incremental approach to dealing with livestock odor is the use of shelterbelts arranged in strategic designs near and within livestock facilities. This review outlines the various ways that shelterbelts can be effective technology which bio-physically mitigates odor thereby reducing social conflict from odor nuisance. The biophysical potential of shelterbelts to mitigate livestock odor arises from the tree/shrub impacts on the central characteristics and physical behavior of livestock odor. As the majority of odors generated in animal facilities that are detectable at appreciable distances travel as particulates, there is compelling evidence that shelterbelts can ameliorate livestock odor by impeding the movement of these particulates. Because the odor source is near the ground and the tendency of livestock odor is to travel along the ground, shelterbelts of modest heights (i.e. 20–30 ft) may be ideal for odor interception, disruption, and dilution. Shelterbelts can be adapted to fit almost any production situation. Depending on shelterbelt health, these trees can provide long term, year round odor interception, with increasing effectiveness over time. Additionally, more is becoming known about how landscape aesthetics affect how people might perceive livestock odor, suggesting that landscape elements such as shelterbelts can lead to aesthetic improvements and perhaps more positive opinions of livestock odor and the farm systems that create them.

/pdf/mitigating-swine-odor-with-strategically-designed-52zij93z76.pdf

Mitigating swine odor with strategically designed shelterbelt systems: a review

The state of Iowa possesses the largest quantity of corn stover in the United States. With a representative survey we examine what Iowa crop farmers think about harvesting and selling corn stover and to what degree they may be interested in providing stover to a biorefinery. Iowa farmers are in an overall learning phase regarding corn stover yet believe that harvesting stover will require an increase in capital investment, additional managerial knowledge and a well-developed support infrastructure. The data suggests some degree of farmer ambivalence regarding what institutional support would be needed to facilitate market entry. Statewide, only 17% of Iowa’s farmers currently express interest in harvesting their stover; though 37% are undecided. The farmers who are interested in marketing stover tend to be: younger, will be farming in 10 years, are at least somewhat knowledgeable about stover, manage large amounts of land and have hectares currently in continuous corn rotations. Regionally, farmers in North Central, IA–the Iowa region with the highest capacity to produce corn stover–tended to be more interested in harvesting stover. Environmental concerns that appear to be important stover supply barriers as farmers who anticipate the negative impacts of corn stover removal on environmental quality tend to be less interested in harvesting corn stover. Overall, the results of this study strongly suggest that future supply assessments consider farmer participation more explicitly and forego arbitrary assumptions regarding farmer behavior as previous supply analyses may have overstated the proportion of farmers interested in harvesting stover.

Joe P. Colletti

Papers

Riparian forest buffers in agroecosystems - lessons learned from the Bear Creek Watershed, central Iowa, USA

Mitigating swine odor with strategically designed shelterbelt systems: a review

Corn stover as a biofuel feedstock in Iowa’s bio-economy: An Iowa farmer survey

Valuation of open space and conservation features in residential subdivisions.

Riparian and Upland Buffer Practices