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agro-ecosystem Emergy Evolution and Trend in Hunan Province

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Asian Agricultural Research 2012年第11期4卷 94-101,105页

作者： ZHU Yu-lin LI Ming-jie HOU Mao-zhang LI Sha LONG Yu-zi WANG Mao-xi School of Economy Central South University of Forestry & Technology Economic Research Center for Agriculture and Forestry Central South University of Forestry & Technology

Using the emergy analysis method,we conduct trend analysis of changes in the total emergy,input and output structure,various emergy indicators of agro-ecosystem in Hunan Province during the period 1999-2008.The results show that during the study period,total emergy input basically remained stable,but the emergy input structure was constantly optimized,of which the input of non-renewable industrial assistant emergy increased by 38.4%,from 4.00E +22 sej to 5.53E +22 sej,and the input of renewable organic emergy declined from 1.32E +23 sej to 1.20E + 23 sej;total emergy yield and yield efficiency of this system were promoted dramatically,and in 2008,the total emergy yield reached 1.69E +23 sej,increasing by 23.8% as against that in 1999,the net emergy yield ratio rose from 0.79 to 0.96;since the environmental loading ratio also tended to rise constantly,from 1.12 to 1.79,the sustainability index of this system also experienced the slow downward trend,from 0.71 to 0.54,always less than 1,indicating that the agriculture in Hunan Province is the high consumption-driven ecosystem in general,with obvious features of extensive development.

关键词： agro-ecosystem Emergy Evolution and trend Hunan Pr

The breaking and reconstruction of nutrient recycling chains in agro-ecosystem in China

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The breaking and reconstruction of nutrient recycling chains...

Spatial and temporal variability of soil freeze-thaw cycling across Southern Alberta, Canada

International Symposium on Phytoremediation and ecosystem Health

作者： Luqiang Zhang College of Life Science Shandong University of Technology

＜正＞Chinese traditional farming technology is primarily environmental-friendly agriculture or eco-agriculture.But along with the transition to massive production,market economy and the urban and rural division,agric... 详细信息

关键词： agro-ecosystem breaking China nutrient recycling chain reconstruction

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Agricultural Sciences 2011年第4期2卷 392-405页

作者： Andrew J. Phillips Nathaniel K. Newlands 不详

Soil freeze-thaw cycles play an important role in all aspects of agro-ecosystems, such as crop productivity, the evolution of the soil matrix, including trace-gas emissions. In regions that experience synoptic weather conditions throughout the winter, freeze-thaw cycles generally occur in one of two categories;seasonal or winter cycles. Current soil vegetation atmosphere models (SVAT’s) often include a heat-transport soil freeze-thaw algorithm, but lack detail on complex interactions between the main driving variables. Boundary conditions for these models are often based only on a few climate variables and typically lack regional context. A nested statistical analysis was applied to identify the optimal set of environmental variables (via a stepwise regression selection procedure) to track soil freeze-thaw dynamics. Historical data collected between the years 2006-2009, for 17 long-term climate stations distributed across southern Alberta Canada was utilized. Cross-correlation between wind speed and maximum air temperature identified Chinook-driven freeze-thaw events, with such interaction varying significantly across the region and by soil depth. Climate-soil interactions were most significant predictors of soil temperature during winter months. The seasonal freeze-thaw cycle is estimated to vary between 112 - 131 days, consisting of 12 - 20 winter cycles (1 cm depth), and 1-5 winter cycles (5 cm depth) with average lag time of 26 - 112 days. Freeze-thaw prediction was greatly improved when higher-order climate interaction terms were considered. Our findings highlight the importance for soil-water and more complex ecosystem, SVAT models to better resolve regional-driven climatic trends. Alongside improved representation of regional trends aimed at reducing model-based uncertainty, such efforts are expected to, in tandem, help advance the geostatistical design, and implementation of agroenvironmental monitoring systems that combine in-situ and satellite/remote-sensing derived estimates of near-surface soil moistu

关键词： Freeze-Thaw Soil Temperature agro-ecosystem Modeling Regional Climate Soil Science

Enhancing the Social and Natural Capital of Canadian agro-ecosystems through Incentive-Based “Alternative Land Use Services” (ALUS) Programs: Recurring Themes and Emerging Lessons

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Journal of Geoscience and Environment Protection 2019年第12期7卷 139-162页

作者： Robert France Jeffrey Campbell Kate Sherren Rural Research Centre Faculty of Agriculture Dalhousie University Halifax Canada School for Resource and Environmental Studies Dalhousie University Halifax Canada

Alternative Land Use Services (ALUS) is an incentive-based program established in Canada to pay farmers for their voluntary delivery of ecosystem services (ES). All seven ALUS programs across the country were examined using a standardized case-study approach based on site visits, reading internal documents, attending program meetings, and engaging in semi-structured interviews with program administrators, participating farmers, and advisory board members. Direct content analysis was used to highlight recurrent themes and emerging lessons in relation to the salient particulars of program physical location, administration framework, delivery of ES, and development and receipt by communities. Our three major findings are: 1) Overall, ALUS has been judged by participants to be a very successful program, whose strength is that it is completely voluntary, non-permanent, and readily adaptable to each location’s environmental conditions, economic funding base, and cultural milieu. 2) One serious shortcoming of all ALUS programs is a general lack of quantifiable data on their ability to increase ES. Instead, environmental benefits are either assumed or based on the idea that the areal extent of enrolled land is the sole measure of its environmental worth. 3) It may be that the social impact of ALUS is its greatest success. In this regard, for farmers, it is the process of engaging in land-use decision making and the recognition of their role as environmental stewards that is a bigger motivation for participating in an ALUS program than the modest financial incentives which they receive.

关键词： agro-ecosystem Services Incentive Payments Grassroots Participation Natural and Social Capital

The Shift of Traditional agroecosystems in the in Eastern Arc Catchments of Tanzania

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Agricultural Sciences 2019年第10期10卷 1343-1358页

作者： Agnes G. Kapinga Abimbola Sangodoyin Olayinka O. Ogunkoya Marko B. Sulley Franco J. Mbegallo Gordon T. Madamombe Department of Environmental Management Pan Africa University Life and Earth Sciences Institute (PAULESI) University of Ibadan Ibadan Nigeria Department of Agriculture and Environmental Engineering University of Ibadan Ibadan Nigeria Department of Department of Geography Obafemi Awolowo University Ile-Ife Nigeria Pan Africa University Life and Earth Sciences Institute (PAULESI) University of Ibadan Ibadan Nigeria Department of Agricultural Economics and Business University of Dar es Salaam Dar es Salaam Tanzania Environmental Management Renewable Energy and Climate Change Research Centre Harare Institute of Technology Harare Zimbabwe.

The purpose of this study was to identify the drivers of the shift of traditional agro-ecosystems and their implication on catchment resources management of Eastern Arc Catchments of Tanzania. Lower Mngeta and Upper Zigi water catchments are situated within Eastern Arc Mountains of Tanzania. Household questionnaire, key informant interviews and focus group discussion were used for collecting primary data. The findings indicated that most of the participants (85.9% and 90.4% in Lower Mngeta and Upper Zigi catchments respectively) depend on subsistence rain-fed agriculture for their livelihoods. However, there are significant changes in production as a result of land fertility deteriorating and negative climatic changes (seasonal shift). This has become a major challenge for most of the farmers. To cope with agro-ecosystem dynamics, farmers in the study areas use both traditional and modern strategies as illustrated in the results section. While tradition always reported to be inexpensive, some modern agro-ecosystem practices reported to cause siltation, killing of fish and herbal plants, easy rotting of seeds (for maize) and bad aroma (for rice)in spite of having a high rate of return. It was also reported that depletion of traditions and norms of conduct, accelerated by multi-cultural interaction from immigrants, have led to deterioration of traditional agriculture practices. Moreover, arrival of agriculture companies and introduction of spice farming was reported to have caused manpower imbalance, unequal distribution of natural resources and less diversity of indigenous plants. The study concludes that communities are much into economic opportunity derived from agro-ecosystem than stewarding it. The study recommends that the effort restoring catchment ecosystem should come from both traditional and modern strategies so as to harmonize and accommodate environmental, economic and traditional values.

关键词： agro-ecosystem Culture and Diversity

Measurement on the Harmony Coefficient of agro-eco-economic System in the Arid Region

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Asian Agricultural Research 2016年第8期8卷 47-52页

作者： Qijun LIU Zhaonan LI School of Economics Beifang University of Nationalities

On the basis of the present research progress of ecological agriculture,we take Minle County and Linze County located in the middle reaches of Heihe River as the typical research units.Based on the rural social and economic data during the period of 2000-2010,theory and method of mathematical statistics are used to establish the measure theory and model of agro-eco-economic system harmony coefficient,including efficacy function,function of harmony coefficient,harmony coefficient and level of harmony coefficient.Based on the actual situation of research region,evaluation indicator system of agro-eco-economic system is established and measurement is carried out.Results show that the regional agro-eco-economic system in research region was in a serious imbalance in 2000-2013.The harmony coefficient of Minle showed a slight rise from 2000 to 2004,and then presented a fluctuating decline.Its rank of harmony coefficient experienced serious imbalance-extreme imbalance-moderate imbalance-low imbalance-serious imbalance-high imbalance.At the same time,the similar tendency happened in Linze County.The measuring results of subsystem in 2000-2013 further indicated that except that the harmony coefficient of economic subsystem in Minle County and Linze County was moderate and high,the ecological subsystem was at Level II and Level III,and social subsystem was at Level IV and Level III,in high and low imbalance status.Finally,several recommendations were put forward for optimizing agro-eco-economic system.

关键词： Middle reaches of Heihe River agro-ecosystem Harmony coefficient

Levels of Heavy Metals in the Soil: Effects of Season, agronomic Practice and Soil Geology

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Journal of Agricultural Chemistry and Environment 2015年第4期4卷 109-117页

作者： Monsurat Temitope Osobamiro Gregrory Olufemi Adewuyi Department of Chemical Sciences Olabisi Onabanjo University Ago-Iwoye Nigeria Department of Chemistry University of Ibadan Ibadan Nigeria

Heavy metals status of agricultural soils should be monitored in order to prevent soil-plant pollution. This study evaluates the effect of season, agronomic practice and soil mineral composition on the levels of some heavy metals (Pb, Mn, Ni, Fe, and Zn) in the arable and oil palm soils of three Farm Settlements in Ogun-State Southwest, Nigeria. Soil samples were collected in two consecutive seasons between 2010 and 2012 and digestion was carried out using Standard Wet Acid Digestion method. Total heavy metals in the digest were determined using Flame Atomic Absorption Spectrophotometer (FAAS). The total levels of heavy metals (in mg/kg) found in the sampled soils were as follows: in the rainy season Mn (28.4 - 34.2), Fe (1599.7 - 2013.2), Pb (11.0 - 16.9), Zn (100.5 - 112.9) and Ni (11.3 - 13.8) and in the dry season Mn (32.1 - 40.1), Fe (1701.4 - 2455.5), Pb (13.0 - 18.7), Zn (105.7 - 110.4) and Ni (15.5 - 16.3). Levels of the heavy metals found in the sampled soils were significantly lower (p < 0.05) than their permissible levels in agricultural soils. Although the levels of heavy metals determined in dry season were higher than those of the rainy season, the only seasonal difference was that of Fe in Sawonjo soil significant at p = 0.05. The level of heavy metals in oil palm soils was significantly higher than the level in arable soils (p < 0.05). At present, pollution level of heavy metals in the sampled soils is low and poses no environmental risk, yet, they have to be regularly monitored before they bio-accumulate into toxic. Government should therefore set up soil monitoring agency and provide irrigation facilities to encourage dry season farming.

关键词： Heavy Metal Farm-Settlement agro-ecosystem Seasonal Variation Soil Mineral

Emergy Analysis of the Agricultural Eco-economic System in Dongting Lake Area of Hunan Province

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Meteorological and Environmental Research 2013年第11期4卷 63-66页

作者： Yulin Zhu Chang Tan Mingjie Li Yuzi Long Maoxi Wang Maozhang Hou Xiaomin Li School of Economics Central South University of Forestry and Technology Agricultural and Forestry Economics Research Center Central South University of Forestry and Technology

[ Objective] The reseamh aimed to discuss eco-efficiency of the agro-ecosystem in Dongting Lake area of Hunan. [ Method] By referring to emergy reseamh method, emergy structure, function and efficiency of the system were analyzed according to emergy input -output data of the system in 2009. [ Result] The system had developed economy, and mechanization and modernization degrees were higher. Emergy output of the system was unbalanced, and market pricing of the agricultural product was significantly lower, especially farming product. Seen from sustainable development index and environmental loading ratio of the system, the system was full of vitality and development potential. The pressure of natural resources and environment was not very great, but the system accommodated too many populations. [ Conclusion] Basic direction of the agricultur- al policy in the zone was further shortening industrial and agricultural price scissors, continuing to implement price protection of the farming product, adjusting agricultural and product structures and transferring surplus labor.

关键词： Emergy analysis agro-ecosystem Dongting Lake area China