基于PSR模型的粤北山区农户行为对水土流失的影响研究

[目的]了解农户自身行为对水土流失影响,为保护和改善粤北山区生态环境、实现精准贫困和区域可持续发展提供依据。[方法]以贫困胁迫下的粤北山区农户行为为研究对象,采用参与式农村评估(PRA)进行农户调查,并通过"压力—状态—响应(PSR)"模型建立粤北山区农户行为对水土流失影响评价指标体系,从农户行为视角出发,结合层次分析法确定各指标权重,定量评价农户行为对水土流失影响程度。[结果](1)由于薪柴依赖度降低、坡耕地比重下降等因素,2012—2016年农户行为对水土流失影响的压力值逐渐降低;(2)虽然农户区水土流失状态值降低,但农户水土保持状态增加,总状态值稍有增加;(3)农户和政府对水土流失治理响应值逐渐增加;(4)综合PSR值,最终农户行为对水土流失影响值稍微降低,生态环境有所好转。[结论]粤北山区农户对水土流失影响压力值降低,状态值增加,最终农户行为对水土流失影响值稍有降低,农户行为对水土流失影响减小。     

环境规制与村规民约对农户绿色生产意愿的影响——以规模养猪户养殖废弃物资源化利用为例

畜禽养殖污染是造成农业污染的重要因素,但现有环境法规作用有限,可能由于没有很好地融合当地的非正式制度。本文在研究环境规制对农户绿色生产意愿的基础上创新性地加入村规民约进行考虑,以湖北省规模养猪户为研究对象,运用结构方程模型分析了环境规制、村规民约对规模养猪户畜禽养殖废弃物资源化利用意愿的影响,探寻正式制度和非正式制度因素对规模养猪户资源化利用意愿的影响机制。研究结果表明：1）环境规制对规模养猪户的资源化利用意愿具有显著正向影响;2）村规民约对规模养猪户的资源化利用意愿具有显著正向影响;3）村规民约在环境规制对规模养猪户资源化利用意愿影响的过程中具有中介作用,具体表现为约束型环境规制借助规范性村规民约间接影响规模养猪户的畜禽养殖废弃物资源化利用意愿,引导型环境规制借助文化性村规民约间接影响规模养猪户的畜禽养殖废弃物资源化利用意愿。据此,本文提出政策启示：在乡村环境治理过程中政府应当完善环境规制、规范村规民约,并在实践中充分发挥两者的优点,使环境规制"合礼"化、村规民约"合理"化。     

DEGRADATION AND RECOVERY PROCESSES IN SEMI‐ARID PATCHY RANGELANDS OF NORTHERN PATAGONIA,ARGENTINA

Vegetation in many arid and semi‐arid shrublands frequently occurs in patches with high plant cover (shrub patches) interspersed in a low‐cover herbaceous matrix (inter‐shrub areas). We hypothesized that (a) livestock grazing is an important determinant of such spatial patterns of vegetation, and (b) redistribution of soil resources associated with shrub patches helps in the recovery of vegetation in inter‐shrub areas. To test these hypotheses, we (a) used line transects to compare spatial variations in vegetation, soil microtopography, and soil physicochemical properties in grazed areas and areas protected from grazing since 1970, (b) added sediment and seeds to inter‐shrub areas, and (c) measured resource redistribution after a wildfire. Results were consistent with the hypotheses. They indicated greater spatial heterogeneity in vegetation, soil microtopography and soil physicochemical properties in grazed areas than in protected areas, and that addition of sediment and seeds or redistribution of soil resources from shrub patches after a wildfire enhanced re‐establishment of vegetation in degraded inter‐shrub areas. As a synthesis, a conceptual model of degradation and recovery processes in semi‐arid shrublands of Northern Patagonia is presented. Copyright © 2011 John Wiley & Sons, Ltd.     

Widespread Deficiencies of Sulfur,Boron, and Zinc in Indian Semi-Arid Tropical Soils: On-Farm Crop Responses

On-farm studies were conducted during 2002–2004 to determine fertility status, including sulfur (S) and micronutrients, and crop response to fertilization on farmers' fields in the semi-arid zone of India. Nine hundred-twenty four soil samples taken from farmers' fields, spread in the three districts of Andhra Pradesh (India), were analyzed for soil chemical fertility parameters. Results showed that samples were low in organic carbon (C), total nitrogen (N), and low to moderate in extractable phosphorus (P), but adequate in available potassium (K). Analyses of soil samples for extractable S and micronutrients was most revealing and showed that 73–95% of the farmers' fields were deficient in S, 70–100% in boron (B), and 62–94% in zinc (Zn). On-farm trials conducted during three seasons (2002–2004) showed significant yield responses of maize, castor, groundnut, and mung bean to the applications of S, B, and Zn. The yield responses were larger when S, Zn, and B were applied along with N and P. Applications of S, B and Zn also significantly increased the uptake of N, P, K, S, B, and Zn in the crop biomass. Results show widespread deficiencies of S, B, and Zn under dryland agricultural conditions; results also show that the nutrient deficiencies can be diagnosed by soil testing. It was concluded that the drylands in the semi-arid regions of India were not only thirsty (water shortage), but also hungry (nutrient deficiencies).     

Farmers' perceptions of soil erosion and its consequences in India's semiarid tropics

This paper investigates farmers' perceptions of soil erosion and how it affects crop yields, land values, and private conservation investments in India's semiarid tropics. It is based on three types of data: (1) a survey of farmers in three study villages; (2) a plot survey by a professional soil surveyor in the same villages; and (3) experimental and simulated data from nearby research stations with similar conditions. Farmers' perceptions of erosion are compared to the surveyor's using kappa, a statistical measure of interrater agreement. Perceived erosion–yield relationships are estimated econometrically and compared to experimental and simulated data. Effects on land values and conservation investments are estimated econometrically. Findings suggest that farmers are keenly aware of rill erosion but less aware of sheet erosion; kappa values ranging from 0 to 0·28 suggest low agreement with the soil surveyor. They anticipate annual yield losses of 5·8–11 per cent due to rill erosion; these figures are reasonably consistent with those from nearby research stations. They anticipate yield increases of 3·8–14·5 per cent due to installation of soil conservation bunds, largely because they can harvest soil from up the slope and capture organic matter. Perceived erosion has some effect on land values and soil conservation investments, but other factors such as irrigation and soil type have a much greater effect. These findings suggest that promoting soil conservation requires capitalizing on farmers' interest in short‐term gains, such as from water and nutrient management. Copyright © 2005 John Wiley & Sons, Ltd.     

Determinants of farmers' willingness to pay for soil conservation practices in the southeastern highlands of Ethiopia

This paper examines the determinants of farmers' willingness to pay for soil conservation practices in the highlands of Bale, southeast Ethiopia. The paper is based on analysis of data collected from 100 randomly selected household heads. The study applied Contingent Valuation Method for the purpose of eliciting farmers' valuation of soil conservation practices in terms of both cash payment and labour contribution. The results reveal that farmers in the study area are less willing to pay cash for soil conservation measures. In terms of labour contribution, however, it was found that they are willing to spend a substantial amount of time per week. Results from logistic regression analysis show that farmers' decisions to participate in soil conservation practices are influenced by a host of factors. The implication is that taking these factors into account while planning soil conservation measures enables policy makers to come up with projects that win acceptance by the local people. Copyright © 2004 John Wiley & Sons, Ltd.     

Integrated soil management in eroded land augments the crop yield and water-use efficiency

Abstract

Cultivated lands in erosion prone agro-ecologies incessantly experience a substantial loss of productive soil and organic matter. Currently, the fertility-management and rainwater-conservation practices are given emphasis separately. This study appraised collectively both the water-conservation and fertility-management practices for the restoration of soil productivity in eroded farmlands. Field experiments were carried out on wheat (Triticum aestivum L.) and maize (Zea mays L.) in eight farmer fields. Four fields of Missa soil series (Typic Ustochrept) and four of Rajar soil series (Typic Ustorthent) were selected. Treatments in each field were: farmers' practice as control without soil-water conservation, and with farmers' rate of fertilizer (per hectare 40 kg N + 30 kg P₂O₅); improved fertilization (per hectare 100 kg N, 60 kg P₂O_5, 2 kg Zn, and 1 kg B) without soil-water-conservation practices; soil-water-conservation practices (deep plowing, bund improvement, ploughing across the contour) + farmers' rate of fertilizers; and soil-water conservation + improved fertilization. Crop grain yields were at the highest with soil-water conservation + improved fertilization (per hectare wheat 3.31 Mg and 1.65 Mg in 2004–2005 and 2005–2006; and maize 4.55 Mg and 4.19 Mg in 2005 and 2006, respectively). The lowest yields were recorded under farmers' practice for both crops. Similar was the response for water-use efficiency and plant uptake of nitrogen, phosphorus, zinc, and boron. Missa soil series was more responsive than was Rajar to integrated soil-management practices. Synergistic application of soil-water conservation and improved fertilization practices significantly improved the crop yields, nutrient uptake, and water-use efficiency.     

Participatory soil and water conservation planning using a financial analysis tool in the West Usambara highlands of Tanzania

Despite decades of soil and water conservation (SWC) efforts in Tanzania, the adoption of the recommended SWC measures by farmers is minimal. In the past, SWC plans did not incorporate farmers' knowledge, and the economics of SWC was not given much attention at the planning stage. This research evaluated the applicability of two tools for participatory soil erosion mapping using farmers' indicators of soil erosion and financial analysis of SWC measures at the planning stage. The two tools were evaluated in Kwalei catchment in the West Usambara highlands, Tanzania. The participatory soil erosion‐mapping tool uses farmers' indicators of soil erosion to identify, classify and map soil erosion at the catchment level. The financial analysis tool involves farmers in a stepwise analysis of the costs and benefits of SWC measures before the implementation. The erosion‐mapping tool increased farmers' awareness on the severity of soil erosion problems, and they realised the need for SWC plans at both field and catchment scales. With the financial analysis tool farmers participated in the cost and benefits analysis and were able to select SWC options that were feasible under their socio‐economic situation. The two tools were able to demonstrate that farmers' participation in SWC planning increases the acceptance of SWC measures because they solve problems that are perceived by themselves. The financial analysis tool demonstrated how farmers could make selection of SWC measures that are feasible under their biophysical and economic condition if they are informed about the costs and benefits. Copyright © 2006 John Wiley & Sons, Ltd.     

Alleviation of Multinutrient Deficiency for Productivity Enhancement of Rain-Fed Soybean and Finger Millet in the Semi-arid Region of India

Soil nutrient contents were determined in 802 surface soil samples (0–15 cm deep) collected from farmers' fields that support extensive cultivation of soybean (Glycine max L.) and finger millet (Eleusine coracana G.), spread across three districts, in the semi-arid regions of Karnataka, India. Following soil analysis, on-farm crop trials were conducted during 2005–2007 to study the crop response to the soil application of nitrogen (N), phosphorus (P), sulfur (S), boron (B), and zinc (Zn) fertilizers. Analyses of soil samples revealed that 4–83% fields were deficient in N, 34–65% in P, 83–93% in extractable S, 53–96% in B, and 34–88% of farmers' fields were deficient in Zn. On-farm trials conducted during the three rainy seasons (2005, 2006, and 2007) significantly (P ≤ 0.05) enhanced crop productivity indices such as yields of grain, stover, and total biomass in soybean and finger millet crops. Integrated management of deficient nutrients in finger millet and soybean crops significantly enhanced the grain and straw uptake of N, P, K, S, and Zn.     

三峡库区水土保持工程农户参与行为调查

[目的]研究三峡库区水土保持工程农户参与程度、参与阶段性特征及主要影响因素,为区域水土保持生态环境建设提供决策参考。[方法]采用参与式农户评估法调查了113户农户,并通过深度访谈重点了解农户对水土保持的相关诉求,运用二元逻辑回归模型分析了农户参与水土保持工程的主要影响因素。[结果](1)库区农户对水土保持的认知度和对水土保持工程的满意度均不高。(2)库区农户多以有偿投工方式参与水土保持工程;农户参与程度低,以零参与和低度参与为主,中度参与和高度参与仅占12%。水土保持工程规划设计、施工、后期管护三阶段农户参与比例分别为19%,42%和2%。(3)参与工程能否挣钱和农户对水土保持的认知是影响农户参与水土保持工程的主要因素。农户参与工程收入越多、水土保持认知度越高,其参与水土保持工程积极性越大。[结论]三峡库区农户水土保持认知度偏低,农户参与水土保持工程偏少,参与阶段主要集中在施工期,不利于水土保持工程的开展和效益发挥。今后要加强水土保持宣传和教育,改革农户参与激励机制,增强水土保持工程实用性和适宜性,以更好发挥水土保持工程的作用。     

Scientific evaluation of smallholder land use knowledge in Central Kenya

The following study was conducted to determine smallholders' land use management practices and agricultural indicators of soil quality within farmers' fields in Chuka and Gachoka divisions in Kenya's Central Highlands. Data on cropping practices and soil indicators were collected from farmers through face‐to‐face interviews and field examinations. Farmers characterised their fields into high and low fertility plots, after which soils were geo‐referenced and sampled at surface depth (0–20 cm) for subsequent physical and chemical analyses. Farmers' indicators for distinguishing productive and non‐productive fields included crop yield, crop performance and weed species. Soils that were characterised as fertile, had significantly higher chemical characteristics than the fields that were of poor quality. Fertile soils had significantly higher pH, total organic carbon, exchangeable cations and available nitrogen. Factor analysis identified four main factors that explained 76 per cent of the total variance in soil quality. The factors were connected with farmers' soil assessment indicators and main soil processes that influenced soil quality in Central Kenya. Soil fertility and crop management practices that were investigated indicated that farmers understood and consequently utilised spatial heterogeneity and temporal variability in soil quality status within their farms to maintain and enhance agricultural productivity. Copyright © 2007 John Wiley & Sons, Ltd.     

Better land husbandry in Honduras: towards the new paradigm in conserving soil,water and productivity

Land shortages are forcing more smallholder farmers to cultivate tropical steeplands. Resulting accelerated soil erosion is being countered by the promotion of soil conservation (SC) technologies, such as cross‐slope barriers, which aim to reduce soil loss and preserve land productivity. However, farmer adoption rates tend to be low. This is often attributed to the farmers' conservatism or lack of education. Research in Honduras's steeplands demonstrates that farmers value SC, provided that it promotes agricultural production. Field research from 1995–98, involving farmed test plots on slopes greater than 35 per cent (19 degrees), demonstrates that at least one typical SC technology—live barriers of Vetiveria zizanioides (vetiver grass)—has little or no impact on maize yield. This means that farmers see little benefit from their investment in the SC method. They find that erratic rainfall, pests and diseases and a lack of economic resources are far greater threats to their livelihoods than soil erosion. Consequently, SC has a low priority. Keeping soil in place avoids major off‐farm disbenefits. However, the SC technique tested here made no discernible difference to slope foot sediment yields during the life of this study. In sum, a new approach is needed. Promoting ‘Better Land Husbandry’ strategies, which seek to combine farmers' concerns about productivity with conservationists' concerns about reducing soil erosion—often via cover‐management—seem to be the best way forward. Copyright © 2002 John Wiley & Sons, Ltd.     

Different Fractions of Soil Potassium,Olsen Phosphorus,and Available Sulfur Status of Intensively Cultivated Berpura Soil Series of India and Nutrient Indexing of Rice Crop

Berpura alluvial soil series of the Indo‐Gangetic Plains is situated in the Ambala District of the Haryana State of India. Soils of this series had medium concentrations of both potassium (K) and phosphorus (P) and large concentrations of sulfur (S) before 1970. To study different fractions of K, Olsen P, and 0.15% calcium chloride (CaCl₂)–extractable (available) S of soils of the Berpura series and to create nutrient indexing of rice crops growing on this series, surface soil samples were collected from 100 farmers' fields after the harvest of the wheat crop in 2005. During kharif season of same year, samples of upper two leaves at anthesis growth stage of rice crop were also collected from the same 100 farmers' fields that had earlier been sampled for soil analysis. Analysis of soil samples showed more K depletion in soils of this series, of which 86% of farmers' fields were deficient in ammonium acetate (NH₄OAc) K (available K). Thirty and 62% of leaf samples of the rice crop growing on the 100 fields of this series were extremely and moderately deficient in K, respectively. The mean values of water‐soluble, exchangeable, nonexchangeable, lattice, and total K were 10.6, 30.3, 390.0, 8204, and 8635 mg kg^?1, respectively. In soils of this series, 0.123, 0.351, 4.517, and 95.009% of total K were found in water‐soluble, exchangeable, nonexchangeable, and lattice K forms, respectively. On the other hand, long‐term farmers' practice of more application of P fertilizer in wheat crop has resulted in P buildup in the soils of the Berpura series. Olsen P in soils of farmers' fields of this series ranged from 9.0 to 153.0 mg kg^?1, with the mean value of 41.8 mg kg^?1. Eighty‐two percent of leaf samples of rice crops grown on this series without application of P fertilizer were sufficient in P. The analysis of soil and rice crops for P and K proved the suitability of 0.5 M sodium bicarbonate (NaHCO₃) and 1 N NH₄OAc for extracting available P and K, respectively, in alluvial soils of the Indo‐Gangetic Plains. The 0.15% CaCl₂–extractable S in this soil ranged from 9.6 to 307 mg kg^?1 with a mean value of 34.6 mg kg^?1. Four and 26% of soil samples had low and medium, respectively, in 0.15% CaCl₂–extractable S. S deficiency was recorded in rice crops, as 29% of the leaf samples were extremely deficient in S and 58% were moderately deficient in S. This indicated the unsuitability of the 0.15% CaCl₂ to extract available S from the Udic ustochrept utilized for cultivation of rice crops.     

三峡库区农户水土保持行为类型及其机理

[目的]分析三峡库区农户水土保持行为的类型、特点、机理和主要效果,为区域水土保持和生态环境建设决策提供依据。[方法]对三峡库区(重庆段)5个区县113户农户进行了问卷调查和重点访谈,运用调查数据分析库区农户水土保持行为类型及其机理。[结果]三峡库区农户水土保持行为主要分自觉自愿型和政策引导型两大类。自觉自愿型是农户创造性地适应环境、保护耕地,降低投入、增加收入,以农户耕地管理和保护性耕作行为为主,农户的水土保持需求形成农户水土保持动机,产生了开挖边沟背沟、挑沙面土、大横坡+小顺坡耕作、等高耕作、免耕、反坡挖地、作物间作套种、种植植物篱和药物除草等行为。其中,间作套种、开挖边沟背沟、大横坡+小顺坡耕作和挑沙面土4项耕作行为在库区推广较好。政策引导型行为是农户受国家水土保持政策引导而参与水土保持生态建设,是国家战略需求和农户实际需要的有机结合,可以细分为三种类型,一是劳务报酬类,农户参与坡改梯等水土保持工程建设并获得劳务报酬。二是经济补偿类,农户响应国家水土保持生态建设号召,采取退耕还林等行为并获得一定补偿。三是资金补贴类,农户在政府资金前补助或后补助情况下修建塘库、道路等水土保持设施。[结论]三峡库区农户水土保持经验丰富,各种水土保持行为均具有较好效果,值得在小流域治理等水土保持生态建设中推广。     

Assessing Farmers' Knowledge of Weed Species,Crop Type and Soil Management Practices in Relation to Soil Quality Status in Mai‐Negus Catchment,Northern Ethiopia

Soil quality (SQ) assessment from farmers' point of view can be used as a primary indicator for planning sustainable agriculture. Despite this fact, limited information is documented with regard to SQ indicators, for example weed species, crop types and management practices from farmers' knowledge perspectives. The aims of this study are to analyse factors that determine farmers' knowledge of SQ, identify SQ indicators of weed species and crop types across different SQ status and assess soil‐and‐crop management practices that maintain SQ in the Mai‐Negus catchment, northern Ethiopia. Fifty‐two farmer household heads were chosen randomly for questionnaire interview. The results showed significant (p ≤ 0·05) differences in the proportion of respondents who used different crop‐and‐soil management practices. The success of overall prediction by the logistic regression model (model χ² = 0·84, p < 0·01) and level of model correct predictions (86%) indicated that the explanatory variables have sufficiently explained farmers' knowledge of SQ indicators. Provided that other conditions remained constant, the odds ratio of variables such as farmer experience, access to information, farm location, education, field slope and land tenure have significantly increased the likelihood of farmers for being knowledgeable of SQ indicators. This study also demonstrated that most farmers are knowledgeable in identifying weed species, crop types and management practices across various SQ status, which suggests that such SQ indicators should be used to assess SQ status (degradation severity) while locating fields to be intervened using appropriate management strategies. © 2013 The Authors. Land Degradation & Development published by John Wiley & Sons, Ltd.     

Nutrient losses from rain‐fed bench terraced cultivation systems in high rainfall areas of the mid‐hills of Nepal

Between the elevations of 1000 and 2000 m in the mid‐hills of Nepal, over 12 million people subsist on land‐holdings of less than 0·5 ha. These farmers have limited access to commercial inputs such as fertilisers and are reliant on organic manures for soil fertility maintenance. Participatory research was conducted with farmers on bari land (upper slope rain‐fed crop terraces) in the hill community of Landruk (bench terraces 0–5° slope, 3000–3500 mm annual rainfall, which aimed to develop soil and water management interventions that controlled erosion without resulting in high leaching, and so were effective in minimising total nutrient losses. Interventions tested were the control of water movement through diversion of run‐on and planting fodder grasses on terrace risers on bench terraces. The interventions were effective in reducing soil loss from the bari land in comparison with existing farmer practices, but no effect was observed on nutrient losses in solution form through runoff and leaching. Losses of NO₃‐N in leachate ranged from 17·3 to 99·7 kg ha⁻¹ yr⁻¹, but only 0·7 to 5·6 kg ha⁻¹ yr⁻¹ in runoff. The overall nutrient balance suggests that the system is not sustainable. Fertility is heavily dependent on livestock inputs and if the current trends of declining livestock numbers due to labour constraints continue, further losses in productivity can be expected. However, farmers are interested in interventions that tie ecosystem services with productivity enhancement and farmers' priorities should be used as entry points for promoting interventions that are system compatible and harness niche opportunities. Copyright © 2007 John Wiley & Sons, Ltd.     

COMPARING FARMERS' PERCEPTION OF SOIL FERTILITY CHANGE WITH SOIL PROPERTIES AND CROP PERFORMANCE IN BESEKU,ETHIOPIA

Farmers' perceptions of soil fertility change were compared with observations on soil quality changes and crop performance in soils from a chronosequence representing a range of soil ages since conversion from forest to cropland (0 to 57 years). A majority of the farmers, 92 per cent, had observed a decline in soil fertility on their land. Farmers use crop yield, indicator plants, soil softness and soil colour to judge soil fertility. They identified 11 plants that they used to indicate high soil fertility and four plants that they used to indicate low soil fertility. There was a strong correlation (r = 0·96) between soil organic matter content (loss on ignition) and farmers' ranking of soil fertility based on colour and softness of soil samples from the chronosequence. The biotest experiment with maize showed an exponential decline in biomass production along the chronosequence, confirming the results of farmers' soil fertility ranking. In the biotest, total soil N predicted produced biomass well (r² = 0·95), whereas the relationship with soil available P (Olsen) was less obvious. Among the eight analysed plant nutrients in the maize leaves, N content was found to correlate best with biomass production (r² = 0·94). We conclude (i) that there is good agreement between farmers' knowledge and scientific indicators of soil fertility and (ii) that the major reason for declining soil fertility in Beseku is the decrease in N mineralization over time. Interventions should focus on supporting farmers to implement a diversified nutrient management strategy that can maintain or increase long‐term productivity of the soil. Copyright © 2011 John Wiley & Sons, Ltd.     

水土流失地区精准扶贫政策对农户幸福指数的影响

[目的]研究水土流失地区精准扶贫政策对农户幸福指数的影响,为贫困地区可持续发展提供科学参考。[方法]通过构建农户幸福指数评价指标体系,采取熵值法与加权求和模型对精准扶贫政策影响下的云南省双柏县农户幸福指数进行评价。[结果]在农户幸福指数评价指标的权重中,排在前3位的分别是人均可支配收入、婚姻满意度、生态环境满意度评价指标;双柏县大多数农户对精准扶贫工作认同度较高,总体满意度平均值为67.55分,但是各乡镇农户对政策感知差异较大。收入增减满意度、政策后果满意度、政策宣传满意度是影响双柏县农户对精准扶贫政策总体满意度的关键因素;双柏县农户幸福指数的平均值为65.64分,各乡镇农户幸福指数差异较小,基本维持在59～71分之间。[结论]未来双柏县应以提升农户幸福感和减缓贫困为关键点和突破点,通过精准扶贫政策实现水土流失地区可持续发展。