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Traditional farming is often affected by unpredictable environmental hazards, such as cold or hot weather, typhoons, flood, and drought, and requires considerable labor. To overcome such difficulties, we developed a web-based crop system to monitor and control environmental parameters such as air temperature, air humidity, sunlight intensity, and soil moisture. The system also operates sunlight-blocking curtains, ventilation/cooling fans, water sprayers, and an alarm on the basis of preset values of the parameters or manually online. The monitored parameters are shown on a mobile device through a low-cost open-source IoT platform (NodeMcu). The programs for operations are created in C# and JavaScript. The proposed system helps users grow crops in greenhouses efficiently by controlling the environmental parameters and necessary facilities remotely. [ABSTRACT FROM AUTHOR]

Meeting demand for food, fiber, feed, and fuel in a world with 9.7 billion people by 2050 without negative environmental impact is the greatest scientific challenge facing humanity. We hypothesize that this challenge can only be met with current and emerging technologies if guided by proactive use of a broad array of relevant data and geospatial scaling approaches to ensure local to global relevance for setting research priorities and implementing agricultural systems responsive to real-time status of weather, soils, crops, and markets. Despite increasing availability of field-scale agricultural data, robust spatial frameworks are lacking to convert these data into actionable knowledge. This commentary article highlights this knowledge gap and calls attention to the need for developing robust spatial frameworks that allow appropriate scaling to larger spatial domains by discussing a recently developed example of a data-driven strategy for estimating yield gaps of agricultural systems. To fully leverage research on sustainable intensification of cropping systems and inform policy development at different scales, we call for new approaches combining the strengths of top-down and bottom-up approaches which will require coordinated efforts between field scientists, crop modelers, and geospatial researchers at an unprecedented level.

Meeting demand for food, fiber, feed, and fuel in a world with 9.7 billion people by 2050 without negative environmental impact is the greatest scientific challenge facing humanity. We hypothesize that this challenge can only be met with current and emerging technologies if guided by proactive use of a broad array of relevant data and geospatial scaling approaches to ensure local to global relevance for setting research priorities and implementing agricultural systems responsive to real-time status of weather, soils, crops, and markets. Despite increasing availability of field-scale agricultural data, robust spatial frameworks are lacking to convert these data into actionable knowledge. This commentary article highlights this knowledge gap and calls attention to the need for developing robust spatial frameworks that allow appropriate scaling to larger spatial domains by discussing a recently developed example of a data-driven strategy for estimating yield gaps of agricultural systems. To fully leverage research on sustainable intensification of cropping systems and inform policy development at different scales, we call for new approaches combining the strengths of top-down and bottom-up approaches which will require coordinated efforts between field scientists, crop modelers, and geospatial researchers at an unprecedented level.

This papers presents the growth and fruiting of the Valerii Chkalov, Record, Ferrovia, Kordia, Regina, Stella, Skeena, Bigarreau Burlat, Lapins, Early Star, Samba and Black Star varieties, grafted on the Cerasus mahaleb, L., MaxMa 14 and Gisela-6 rootstocks in different combinations and planted at different distances, which are grown in the southern and central area of the Republic of Moldova have been investigated. The sweet cherry trees with an age between 9 to 14 years that had been grafted on Cerasus mahaleb, L. showed a stronger growth as compared to the trees with an age between 4 to 10 years that had been grafted on Gisela 6, and the tees with an age between 8 to 10 years which had been grafted on MaxMa 14. High vigour trees are grown on non-irrigated soils; the sweet cherry trees, grafted on Gisela 6 and MaxMa 14 rootstocks are grown on fertile well-irrigated soils. The studied associations of varieties and rootstocks turned out to be suitable for cultivation in terms of the soil and climatic conditions of the area. [ABSTRACT FROM AUTHOR]

The conservation of pollinating insects in agriculture is a global concern since the diversity of such organisms may affect the productivity of pollination-dependent crops. In this study, we assessed (i) how distances from natural vegetation affect the diversity (guilds, richness, abundance) of flower-visiting insects within mustard crops in Nepal, (ii) how insect richness and abundance are related to mustard yields (weight of seeds) and (iii) the contribution of flower-visiting insects to mustard pollination by conducting pollinator exclusion experiments. To analyse these data, we carried out (i) hierarchical clustering followed by a Procrustes analysis as well as a generalized linear mixed model and (ii), (iii) linear mixed models. We found that the guild composition was not similar near and far from natural vegetation, indicating a tendency for Apis bees to displace in opposite directions relative to non-Apis bees. Nevertheless, while both richness and abundance were higher nearer natural vegetation, the former showed a stronger and more positive effect on mustard yields than the latter. Furthermore, we found that mustard flowers have a significant requirement for insect pollination since productivity increased by ~70% with insect visitation. Overall, our data suggest that the diversity of flower-visiting insects enlarges nearer to natural vegetation. However, the results indicate that species richness may be more relevant than abundance to mustard production. As such, we suggest that the maintenance of natural vegetation could be considered a strategy for ensuring the presence of multiple pollinator species within mustard fields to promote its long-term sustainability in Nepal. [ABSTRACT FROM AUTHOR]

Lettuce is one of the most popular vegetables, and the market niche of the baby leaf variety is expanding. The manner in which nitrogen (N) is supplied and the available concentration of the micronutrient molybdenum (Mo) affect N metabolism, with reflects on the nutritional quality of that vegetable. Here, two Mo concentrations (0.06 and 0.12 mg/L) and four proportions (%) of nitrate (NO3−)/ammonium (NH4+)(100/0, 75/25, 50/50, and 25/75) were supplied to hydroponic baby leaf lettuce floating type to evaluate their effects on plant growth and leaf mineral and NO3− compositions. Shoot dry mass did not differ among the different treatments, although fresh mass was lower in treatments with larger proportions of NH4+. Higher leaf concentrations of NO3− were observed in plants treated with 100% N–NO3−, but they were still below tolerable limits for human health. The enzyme nitrate reductase was not found to be sensitive to the nitrogen sources or to Mo concentrations. N proportions and Mo concentrations differently affected macro‐ (C, N, P, K, Ca, Mg, and S) and micronutrients (Cu, Fe, Mn, Mo, and Zn) leaf concentrations. Although treatment with 100% N–NO3− favored higher mineral concentrations in lettuce leaves, the addition of 25% N–NH4+ allowed fresh mass production with the lowest NO3− concentrations. As such, and considering the healthy reduction of NO3− consumption by humans and the maintenance of plant productivity, the 75/25 NO3−/NH4+ proportion is recommended for the hydroponic cultivation of baby leaf var. Mimosa lettuce. Practical Application: We demonstrate a direct link between the constitution of nutrient solution with nitrate accumulation by hydroponic lettuce and indicate the best source of N as well as the concentration of Mn to healthy reduction of NO3− consumption by humans and the maintenance of plant productivity. [ABSTRACT FROM AUTHOR]

In recent decades, it has been shown that pollination deficit can significantly affect crop production. Moreover, now it is known that the appropriate management of pollination can increase the quantity and quality of yields. Therefore, pollination appears to be a key component in modern agriculture. This study aimed to determine the impact of floral patch addition on the quality and quantity of Cucurbita maxima fruit production. To this end, we manually added a set of ornamental plant species to the edge of the crop and monitored the pollinator diversity and visit frequency, as well as the seed set and sugar content of the pumpkin yield, in treatment and control parcels. The results showed that there was a higher visit rate in the treated parcel. Only the sugar content, and not the seed set, was affected by the addition of ornamental species and the pollinator visit rate. These findings indicate that the addition of flowering plants can favor different components of the crop yield of this species, but future studies should sample on a broader spatial and temporal scale in order to certify the generalizability of our results.

Abstract Climate Smart Agriculture (CSA) seeks to meet three challenges: improve the adaptation capacity of agricultural systems to climate change, reduce the greenhouse gas emissions of these systems, and ensure local and global food security. Many CSA assessment methods that consider these three challenges have emerged, but to better assess the environmental resilience of farming systems, other categories of environmental impacts beyond climate change need to be considered. To meet this need, we propose the LCA4CSA method, which was tested in southern Colombia for family farming systems including coffee, cane and small livestock production. This methodological framework is based on Life Cycle Assessment (LCA) and multi-criteria assessment methods. It integrates CSA-related issues through the definition of Principles, Criteria and Indicators, and involves farmers in the assessment of the effects of CSA practices. To reflect the complexity of farming systems, the method proposes a dual level of analysis: the farm and the main cash crop/livestock production system. After creating a typology of the farming systems, the initial situation is compared to the situation after the introduction of a CSA practice. In this case, the practice was the use of compost made from coffee processing residues. The assessment at the crop system level made it possible to quantify the mitigation potential related to the use of compost (between 22 and 41%) by taking into account operations that occur on and upstream of the farm. However, it showed that pollution transfers exist between impact categories, especially between climate change, acidification and terrestrial eutrophication indicators. The assessment made at the farming system level showed that farms with livestock units could further limit their emissions by modifying the feeding of animals due to the large quantities of imported cereals. The mitigation potential of compost was only 3% for these farms. This article demonstrates the merits of using life cycle thinking that can be used to inform stakeholder discussions concerning the implementation of CSA practices and more sustainable agriculture. [ABSTRACT FROM AUTHOR]

Abstract The Central Dry Zone (CDZ) of Myanmar is home to an estimated 12 million people, provides 35% of Myanmar's grain cropping, but is underdeveloped and food-insecure. We examined the cropping systems of the CDZ to understand the biophysical drivers of those systems, the need for change to improve productivity and sustainability, and how future research and extension might be framed to best serve the rural communities. Data were sourced from (i) published empirical studies and web-based documents produced by the Myanmar Government and international agencies and (ii) a face to face survey of 190 Central Dry Zone farmers. Our analysis indicates that CDZ cropping systems have low productivity which threatens sustainability and future production. Farmers practice traditional cultivation and remove crop residues to use as animal feed, which together deplete soil organic matter reserves and expose the soil to physical degradation. The soils are generally coarse-textured with low water retention, high leaching potential and nutritionally deficient. Nutrient inputs from farm-yard manure and mineral fertiliser are also low. As a consequence, crop nutrient deficiencies are widespread across the CDZ and a major productivity constraint. Mineral-fertiliser use is increasing however, but farmers are conscious of the need for high-quality advice on how best to use these inputs. A narrow range of crops is grown in the CDZ with ca. 80% of the land used to grow pulse and oilseed legumes and sesame and sunflower, but few cereals. The lack of crop diversity exposes farmers to market price fluctuations and the lack of balance between broadleaf and cereal crops results in disease and yield loss. Climate changes further threaten the sustainability and economic viability of grain cropping with increasing temperatures, more erratic rainfall and fewer but more intense rainfall events during the monsoon. Consequences are more floods and dry periods and increased risk of soil erosion. The imperative now is to transition the upland cropping of Myanmar's CDZ to embrace the basic elements of conservation agriculture, i.e. crop diversity, effective weed control, in situ retention of crop residues, optimised crop nutrition and minimal-to-zero soil disturbance, to sustainably increase crop water use-efficiency and system productivity. Highlights • The biophysical nature of grain cropping in Myanmar's Central Dry Zone described. • Technology and information gaps to improve productivity and sustainability identified. • Key issues are lack of crop diversity, disease, low nutrient inputs and residue removal. • Climate change is challenging farmers as it becomes hotter and rainfall more erratic. • Future cropping must adopt conservation agriculture for improved water-use efficiency. [ABSTRACT FROM AUTHOR]

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Emergence uniformity and the time required for emergence are essential factors for obtaining highly productive potential in plants. Factors such as sowing depth and soil moisture affect uniformity and emergence, but little is known about the impacts of seed vigor. Thus, we determined the impacts of seed vigor on uniformity and growth as well as development and yield in soybean (Glycine max [L.] Merrill) plants. The treatments consisted of four vigor levels (89%, 57%, 47%, and 43%) obtained by accelerated aging, in a randomized block design, with five replicates at three sites. Seeds with the highest vigor level showed higher uniformity and faster emergence. Dominated plants through their phenotypic plasticity modify stem diameter and internode length. The plants that emerged earlier had a larger leaf area in the three stages (V1, V4, and R2), allowing them to accumulate more photoassimilates in the initial stages. Consequently, these plants exhibited an increase in yield components, especially in the number of fertile nodes and the number of pods per plant, making them more productive.

Coffee is considered a boom crop in Southeast Asia. However, while it bears typical boom crop characteristics in many places where it has been grown, in other places it has contributed to agrarian transformation. This paper examines the context of coffee development in the Northwestern Mountain Region of Vietnam and describes how smallholder coffee growing has triggered an agricultural transition process, and corresponding land use changes, from subsistence-based to commercialized agriculture production. The research was conducted in a commune located in Son La province. Interviews with 46 selected households and three focus group discussions (10−15 people each) were conducted to understand changes in crop systems, corresponding land use, and labor use, due to the adoption of coffee (the boom crop). The research found that coffee has replaced swidden crops and enables a multicrop system, with less land devoted to swidden land use. The income from coffee is used to hire labor and to pay for the inputs needed to mechanize rice farming. The research findings show that the coffee boom has brought about livelihood transformation, changed land use, and transformed local livelihoods from subsistence to production for the market.

The frequency and intensity of extreme weather years, characterized by abnormal precipitation and temperature, are increasing. In isolation, these years have disproportionately large effects on environmental N losses. However, the sequence of extreme weather years (e.g., wet-dry vs. dry-wet) may affect cumulative N losses. We calibrated and validated the DAYCENT ecosystem process model with a comprehensive set of biogeophysical measurements from a corn-soybean rotation managed at three N fertilizer inputs with and without a winter cover crop in Iowa, USA. Our objectives were to determine: (i) how 2-year sequences of extreme weather affect 2-year cumulative N losses across the crop rotation, and (ii) if N fertilizer management and the inclusion of a winter cover crop between corn and soybean mitigate the effect of extreme weather on N losses. Using historical weather (1951-2013), we created nine 2-year scenarios with all possible combinations of the driest ('dry'), wettest ('wet'), and average ('normal') weather years. We analyzed the effects of these scenarios following several consecutive years of relatively normal weather. Compared with the normal-normal 2-year weather scenario, 2-year extreme weather scenarios affected 2-year cumulative NO3− leaching (range: −93 to +290%) more than N2O emissions (range: −49 to +18%). The 2-year weather scenarios had nonadditive effects on N losses: compared with the normal-normal scenario, the dry-wet sequence decreased 2-year cumulative N2O emissions while the wet-dry sequence increased 2-year cumulative N2O emissions. Although dry weather decreased NO3− leaching and N2O emissions in isolation, 2-year cumulative N losses from the wet-dry scenario were greater than the dry-wet scenario. Cover crops reduced the effects of extreme weather on NO3− leaching but had a lesser effect on N2O emissions. As the frequency of extreme weather is expected to increase, these data suggest that the sequence of interannual weather patterns can be used to develop short-term mitigation strategies that manipulate N fertilizer and crop rotation to maximize crop N uptake while reducing environmental N losses. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to observe and reevaluate the influence mineral and organic fertilizers have on soil reaction. Various dosages of fertilizer have been applied, chemical as well as natural (manure) and comparisons were made regarding their influence, depending on the culture system (intensive and superintensive) without changing the dosage, but taking fruit tree density per hectare into account. Research in this paper was carried out on an experimental field at the Didactic Station of the U.A.S.V. M. B. in Timişoara during 2016-2017 and later in the research laboratories of the Departments of Soil Science and Agro-chemistry of the Faculty of Agriculture in Timişoara. The soil on which the experiment is placed, is a chernozem, moderate gleized cambic, weakly decarbonated, clayey, on medium fine loss layers. The experiment is polyfactorial, type 2 x 6: factor A - the crop system: a1 - the intensive system; a2 - the superintensive system. Factor B - doses of fertilizer. The experiment includes 12 alternatives. Each alternative includes 4 trees, between the alternatives have been left two trees for insolation, between the repetition have been left four trees. In conclusion, a slight soil acidifying was accounted for, with the intensive system as well as with the superintensive one, on applying a combination of mineral + organic fertilizers. Also, the soil pH shows lower values in both culture systems when a higher dosage of mineral fertilizer is applied. [ABSTRACT FROM AUTHOR]

Pesticides are chemicals that help protect plants from any external damage caused by insects or parasitic weeds. The research aims to compare different effects of pesticides on plant protection. A quantitative research methodology is used in this research. An experiment was conducted using different types of pesticide that have been tested separately for a given time period. Afterwards, data from each experiment was recorded. It has been shown that each type of pesticide serves a distinct purpose. The results obtained prove that the usage of pesticides has a positive effect on plant growth, which prevents parasites and pests from invading the plant. Pesticides can promote healthy plant growth and many other positive outcomes. Despite this, it has an impact on the surrounding environment and has the potential to contaminate the soil. Recommendations are made for future research to improve plant protection from external damage via the use of organic pesticides. [ABSTRACT FROM AUTHOR]

Efficient use of freshwater resources is necessary to balance food production and long-term sustainability of irrigated agricultural systems. Here we developed a framework to benchmark irrigation water use relative to crop yield for individual fields based on site-specific weather and soil. Subsequently, we used the framework to diagnose on-farm irrigation management, in relation to crop production, in maize and soybean producer fields in Nebraska (USA). We found actual irrigation to be similar to estimated irrigation water requirement in about half of the fields (i.e. small water surplus). Remarkably, these fields attained yields similar to fields where actual irrigation exceeded water requirements (i.e. large water surplus). Underlying causes for water surplus included producer risk aversion in soils with low water storage capacity, use of coarse methods for scheduling irrigation, and tillage. Scenario assessment indicated that total irrigation volume could potentially be reduced up to 25%–40%, without hurting crop yields, by reducing current irrigation surplus in years with above- or near-average seasonal precipitation. About a third of the producer fields already achieved high yields with little water surplus, supporting the contention that achieving high productivity with less irrigation by better matching irrigation amounts in relation with crop water requirements are compatible goals. The proposed framework can be applied to other crops and regions provided there are well-validated models, local soil and weather datasets, and reliable field-level irrigation, yield, and management records.

In Reserva Natural de Castro Marim e Vila Real de Santo António (SE of Portugal), most of the salt marshes and saltpans are abandoned contributing to their degradation and, consequently, alteration of some ecological conditions. Rehabilitation of these areas by aSalicorniacrop can contribute to their economic and environmental improvement by stimulation of biogeochemical processes and biomass commercialization. However, the development of agro-techniques adjusted to species and variable environmental conditions from Mediterranean are needed in order to improve theSalicorniacrop. This study aimed to evaluate: i) potential use of seedlings from greenhouse in the field cultivation; and ii) survival, growth and yield ofSalicorniaunder shading and different salinity conditions of the soils and irrigation waters. AutochthonousSalicorniaspecies (S. ramosissimaandS. patula) were tested. Germination tests under controlled conditions andin situmesocosm assays were carried out. Assays were realized with a low density of seedlings from natural conditions and greenhouse, and soils and waters from estuary both with different salinities. Intermediate and high salinities (25–45 dS/m) affected onlyS. patulagermination. In general,Salicorniagrowing in soils with low salinity had great fresh biomass accumulation independently of seedling source (from natural conditions and greenhouse) and/or growing season. The shading seems to improve the fresh biomass accumulation and yield. Under Mediterranean conditions, the transplantation ofSalicorniafrom greenhouse to the field was a promising technique, independently of the salinity conditions. This study demonstrated that the abandoned and saline areas can be rehabilitated by a sustainable crop ofSalicornia. [ABSTRACT FROM PUBLISHER]

Estudou-se a comunidade de nematoides do solo em quatro sistemas de manejo no Sistema Integrado de Produção Agroecológica (SIPA): pasto, capoeira, figo com Paspalum notatum e horta. As amostras de solo foram coletadas a cada quatro meses durante um ano. A comunidade de nematoides foi identificada e descrita com os parâmetros: riqueza de famílias, diversidade de Shannon-Weaner, de dominância de Simpson, além da diversidade trófica e dominância trófica. Os fitoparasitas e bacteriófagos dominaram as comunidades de nematoides nas áreas. Osonívoros foram menos abundantes em todos os sistemas estudados. O sistema pasto apresentou maior diversidade de famílias de nematoides enquanto que, no sistema capoeira se encontraram valores de diversidade baixos, porém constantes no tempo, indicando condição de maior estabilidade. A ação antrópica induzida pelo manejo modificou a distribuição trófica em benefício dos nematoides bacteriófagos, normalmente associados à maior taxa de decomposição da matériaorgânica. Nematoides fitoparasitas e bacteriófagos foram dominantes nos sistemas estudados, o que sugere a influência de densidade radicular elevada no pasto e alta taxa de mineralização na horta. A distribuição relativa de grupos tróficos de nematoides do solo confirmou ser uma eficiente forma de se determinar o nível de perturbação de solos submetidos a distintos manejos.microfauna, sistemas de cultivo, diversidade.Soil nematode communities were studied in four differents crop systems at the Integrated System of Agroecological Production. Soil samples were collected at four-month intervals during one year, with three replications for each location. Nematode communities were measured by the following parameters: family richness, Shannon-Weaner’s index, Simpson’s index, trophic diversity (T) and dominance index (Ig). These data were submitted to ANOVA statistical analysis at 5% level of Tukey’s test. The population of bacterivores and herbivore nematodes was high in all areas. Omnivores were found in lower abundance in all systems. The highest diversity of nematode families was found on pasture. In forests, the values of richness and abundance were always lower but constant in time, suggesting an ecosystem of higher stability. Soil management induced the proliferation of bacterivores usually associated with higher decomposition rates of organic matter. Herbivores and bacterivores were dominant in all systems, suggesting it is important to have high root (for pasture) or high decomposition rates (for horticulture system). The relative distribution of trophic groups of soil nematodes proved to be a good way to determine the level of perturbation of ecosystems.

O tipo de cultura e a orientação de semeadura em relação ao declive do terreno podem modificar a proporção e o tamanho dos sedimentos transportados na enxurrada, além da relação do teor de C orgânico nos sedimentos e no solo erodido. Este trabalho teve o objetivo de determinar a proporção e o tamanho dos sedimentos transportados pela enxurrada sob taxa constante desta e o teor de C orgânico contido nos sedimentos e no solo erodido, sob duas formas de semeadura das culturas de aveia e ervilhaca. Quatro testes de chuva simulada foram aplicados entre março e novembro de 2006, durante o ciclo vegetativo das culturas, com intensidade constante de 64 mm h-1 e 1 h de duração de cada teste, em Lages, SC, num Cambissolo Húmico com declividade média de 11,9 cm m-1. Os tratamentos eram formados pela combinação de duas culturas e duas orientações de semeadura em relação ao declive. As culturas utilizadas foram aveia (Avena strigosa) e ervilhaca (Vicia sativa); as formas de semeadura eram: mecanizada em linhas em contorno ao declive e mecanizada em linhas paralelas ao declive (morro abaixo). As amostras de enxurrada para a coleta dos sedimentos foram obtidas sob taxa constante de enxurrada, aos 50 min de duração de cada teste de chuva. A aveia reduziu a quantidade de sedimentos na enxurrada em 46 % em relação à ervilhaca, e a semeadura em contorno, em 56 % em relação à semeadura morro abaixo. A proporção de sedimentos na enxurrada foi diminuída em 63 % entre o início e o final do ciclo das culturas. Na classe de menor tamanho dos sedimentos (< 0,038 mm), a aveia aumentou sua proporção em 17 % em relação à ervilhaca, e o contorno os aumentou em 10 % em relação à semeadura morro abaixo. O índice D50 dos sedimentos presentes na enxurrada foi de 0,043 mm na aveia e 0,119 mm na ervilhaca, e de 0,047 mm na semeadura em contorno e 0,117 mm na semeadura morro abaixo. A razão entre o teor de C orgânico dos sedimentos transportados pela enxurrada e o teor de C do solo na camada de 0-2,5 cm foi de 1,39 na aveia e 1,21 na ervilhaca, e de 1,43 na semeadura em contorno e 1,17 na semeadura morro abaixo.The crop type and seed row direction in relation to the land slope can modify the total amount and size of runoff-transported sediment. They may alter the relation between organic carbon levels in the sediments and the eroded soil. The current study aimed to quantify the sediment size and proportion transported at constant runoff rate and the organic carbon level in the sediments and the eroded soil, under oat and vetch sown in two row directions. Four simulated rainfalls were applied between March and November 2006, during the crop cycle, at a constant intensity of 64 mm h-1 for one hour, in Lages, Santa Catarina, Brazil, to an Inceptisol with a slope of 0.119 m m-1. The treatments consisted of the combination of two crops and two seed row directions in relation to the slope. Oat (Avena strigosa) and vetch (Vicia sativa) were sown mechanically in parallel downhill rows and contour rows of the slope. Runoff sediment was sampled in a set of sieves that collected the constant rate runoff flow for 50 min during each rain test. Oat cropping decreased the amount of runoff-transported sediment by 46 % in comparison to vetch cropping and the contour seed row reduced this by 56 % in relation to downhill seed row. The proportion of sediments in runoff decreased 63 % from the start to the end of the crop cycle. The proportion of the fine size sediment class (< 0.038 mm) was 17 % higher under oat than vetch, and the contour seed row increased the proportion by 10 % in comparison with the downhill seed row. The D50 sediment index in runoff was 0.043 mm in oat and 0.119 mm in vetch; it reached 0.047 mm in the contour and 0.117 mm in the downhill seed rows. The ratio between organic carbon level in sediments and in the 0-2.5 cm soil layer was 1.39 in oat, 1.21 in vetch, 1.43 in the contour and 1.17 in downhill seed rows.

O objetivo deste trabalho foi quantificar as frações de acumulação de fósforo em solo submetido a sucessivas aplicações de dejetos líquidos de suínos (DLS) em sistema de plantio direto. Em Santa Maria, RS, doses de 0, 20, 40 e 80 m³ ha-1 de DLS foram distribuídas a lanço por sete anos agrícolas, antes do plantio de cada cultivo de inverno ou verão, em Argissolo Vermelho arenoso, totalizando 0, 584, 1.168 e 2.336 kg ha-1 de P aplicado via dejetos. O solo foi coletado nas camadas 0-2, 4-6, 8-10, 14-16 e 20-25 cm, e submetido ao fracionamento químico de P. A adição do DLS ao solo durante sete anos aumentou o teor de P até 25 cm de profundidade, principalmente nas frações inorgânicas extraídas por resina trocadora de ânions, NaHCO3 0,5 mol L-1 e NaOH 0,1 mol L-1. As aplicações não aumentaram os teores de P orgânico extraído por NaHCO3 0,5 mol L-1, mas sim as frações orgânicas extraídas por NaOH 0,5 e 0,1 mol L-1. O DLS adicionado ao solo por longo período pouco afeta a partição de P em frações inorgânicas e orgânicas. As sucessivas aplicações de DLS aumentam o acúmulo de P em frações predominantemente lábeis no solo, o que representa um risco potencial para contaminação de águas superficiais e subsuperficiais.The objective of this work was to quantify the accumulation of phosphorus fractions in the soil subjected to successive pig slurry applications in a no-tillage system. At Santa Maria, Rio Grande do Sul state, Brazil, 0, 20, 40 and 80 m³ ha-1 doses of pig slurry were broadcasted for seven years on Argissolo Vermelho arenoso (Arenic Hapludult) before sowing each winter or summer crop, totalizing 0, 584, 1,168 and 2,336 kg ha-1 of P from pig slurry. Soil samples were collected in 0-2, 4-6, 8-10, 14-16 and 20-25 cm layers and submitted to P fractionation. Applications of pig slurry during seven years increased P contents to a depth of 25 cm, especially in the inorganic fractions extractable by anion exchange resin, NaHCO3 0.5 mol L-1 and NaOH 0.1 mol L-1. Pig slurry doses did not increase P content in organic fractions extracted by NaHCO3 0.5 mol L-1, but increased the content of organic fractions extracted by NaOH 0.5 e 0.1 mol L-1. Pig slurry applied to soil for large period has little effect on the P partition in inorganic and organic fractions. Successive pig slurry applications increase P contents in the soil predominantly in labile fractions, which can represent a potential risk for waterbeds contamination.

Com este trabalho, objetivou-se estudar a artropodofauna do solo em cultivo de sorgo (Sorghum bicolor (L.) Moench) em diferentes estações do ano e profundidade do solo, em sistema direto e convencional. O estudo foi realizado de agosto de 1996 a abril de 1997, em área experimental do Departamento de Defesa Fitossanitária, Universidade Federal de Santa Maria, Rio Grande do Sul, Brasil. Para as coletas dos artrópodes utilizou-se extrator de solo, tomando-se amostras em cinco pontos, nas profundidades de 0-5 cm, 5-10 cm, 10-15 cm e de 15-20 cm, em cada estação do ano. A classe Insecta foi a mais expressiva, correspondendo a 87,68% e 100% do número total de artrópodes, respectivamente na semeadura direta e na semeadura convencional. A ordem Coleoptera foi a mais numerosa, com predomínio das formas larvais das famílias Scarabaeidae, Carabidae e Elateridae, correspondendo a 25,0%, 10,8% e 8,8% do total coletado, respectivamente. A artropodofauna do solo variou através do ano e decresceu com o aumento da profundidade do solo.The objective of this work was to study the soil arthropodfauna of sorghum (Sorghum bicolor (L.) Moench) under no-till and conventional systems, in the different seasons of the year and at different soil depths. The trial was conducted from August 1996 to April 1997 in the experimental area of the Plant Protection Department, Federal University of Santa Maria, Rio Grande do Sul, Brazil. An extractor was utilized to collect the arthropods at five spots and four soil depths (0-5, 5-10, 10-15 and 15-20cm), in each season of the year. The Insecta was the most significant class, accounting for 87.68% and 100% of the total number of arthropods, respectively in the no-till and conventional systems. Coleoptera was shown to be the predominant order, with larvae of Scarabaeidae, Carabidae and Elateridae accounting for 25.0%, 10.8% and 8.8% of the total of the specimens collected. The soil arthropodfauna varied throughout the year and decreased with increasing soil depth.

The European political framework of the last decade aims to drive agriculture towards economic and environmental sustainability. Thus, European institutions have paid great attention to environmental impact assessment and to the definition of a complex indicator capable of restoring the multidimensional nature of environmental sustainability. In this work, a possible methodology for assessing the environmental sustainability of European national cropping systems by a synthetic indicator is provided. More specifically, the environmental impact of agriculture is assessed through a synthetic indicator, whose definition is based on a methodological improvement of the ecological footprint approach, which quantifies the balance between exploitation and availability of natural resources used in agriculture. The analysis shows how national cropping systems can contribute to Europe’s environmental impact through agriculture. To assess an eventual relationship between agriculture’s environmental performance and the ability to support more sustainable agriculture at the national level, the results are then compared with the subsidies for agro-environmental measures provided by the second pillar of the CAP. In addition, the synthetic indicator chosen for the study, giving the possibility of quantifying the dynamic of the environmental impact of agriculture between two different periods, permits the analysis of the possible causes that may have generated the observed changes. The implications of this approach should stimulate new reflections on the significance of the ecological relationships embodied into agricultural production and the environmental role of farmers. [ABSTRACT FROM AUTHOR]

A incidência de arroz vermelho na cultura do arroz irrigado tem praticamente inviabilizado o cultivo em muitas áreas do Rio Grande do Sul, destacando-se como um dos principais entraves ao aumento da produtividade. Uma alternativa para minimizar o problema é o sistema mix de pré-germinado, que consiste em utilizar sementes pré-germinadas, em área com vegetação dessecada e previamente inundada. O sistema apresenta vantagens técnicas e econômicas na cadeia de produção. Entretanto, a decomposição anaeróbia da palha presente na área, após o alagamento, pode provocar a formação de substâncias tóxicas afetando o estabelecimento das plântulas. Este trabalho teve como objetivo determinar o efeito do manejo da água de irrigação e das quantidades de palha de azevém no rendimento de grãos e componentes de produção do arroz irrigado no sistema mix de pré-germinado. O experimento foi conduzido em casa de vegetação, no ano agrícola 1998/99, em PLANOSSOLO HIDROMÓRFICO Eutrófico arênico, pertencente à unidade de mapeamento Vacacaí, na Universidade Federal de Santa Maria, em Santa Maria. - RS, utilizando-se a cultivar IRGA 417, em resteva de azevém. Os tratamentos foram avaliados em delineamento inteiramente casualizado, no arranjo fatorial (3x3), com dois fatores: (i) manejo da água em três níveis (lâmina estagnada, com drenagem e com fluxo de superfície) e (ii) palha de azevém em três quantidades (0,00 t ha-1, 3,43 t ha-1 e 6,86 t ha-1). Os resultados evidenciam que, no sistema mix de pré-germinado, mantendo-se uma lâmina estagnada sobre o solo, reduz-se a massa seca total e o rendimento de grãos de arroz em relação ao manejo da água com drenagem e com fluxo de superfície. O aumento na quantidade de palha de azevém na cultura do arroz no sistema de cultivo mix de pré-germinado, sem fluxo de água em superfície ou drenagem, reduz o rendimento de grãos.The incidence of red rice on flooded rice production is a limiting factor in many agricultural areas, when high productivity is the objective. Alternative system of crop cultivation using no tillage on flooded water seed system can be used to minimize the problem. Although this system has technical and economical advantages on the production chain, especially on red rice control, anaerobic process of ryegrass straw decomposition may produce toxic substances to rice plants establishment. The objective of this work was to evaluate the effect of different water irrigation management and the amount of ryegrass straw on grain yield and yield components on paddy rice cultivated. The experiment was conducted in greenhouse, during the 1998/99 crop growing season, on Hidromorphy Planosoil, sandy Eutrophic, soil mapping unit "Vacacaí", over ryegrass crop residue at the Federal University of Santa Maria, Santa Maria, RS. The rice cultivar IRGA 417 was used. A completely randomized design factorial (3x3), three water management (with neither vertical nor surface in-out water flow over the soil, with drainage and surface water flow) and three amount of ryegrass straw (0.0 t ha-1, 3.43 t ha-1 and 6.86 t ha-1). The data demonstrated that a permanent flooding with neither vertical nor surface in-out water flow reduce dry matter above ground and grain yield when compared to the treatments with drainage and surface in-out water flow. Increasing the amount of ryegrass straw on the no-tillage water seed system, with neither vertical nor surface in-out water flow, on the flooded water the grain yield is reduced.

O objetivo deste experimento foi avaliar o efeito de diferentes populações de plantas e espaçamentos entre linhas de cultivo na produção de massa seca, rendimento de grãos e componentes do rendimento da cultura do feijoeiro irrigado. O experimento foi conduzido no ano agrícola 1997/1998, em área do Departamento de Engenharia Rural da Universidade Federal de Santa Maria, RS. A cultivar de feijão preto BR-FEPAGRO 44 - Guapo brilhante, habito de crescimento indeterminado (tipo II), foi submetida a três populações de plantas (175, 250 e 325 mil plantas há-1) e três espaçamentos entre linhas de cultivo (35, 50 e 65cm). Utilizou-se o delineamento experimental inteiramente casualizado, bifatorial, com quatro repetições. Irrigações por aspersão foram aplicadas quando a evapotranspiração máxima da cultura, estimada a partir da evaporação do tanque classe "A", indicava um valor acumulado de 25mm. Os resultados demonstraram que as diferentes populações de plantas e espaçamentos entre linhas de cultivo não ocasionaram alterações no rendimento de grãos e massa de mil sementes. No entanto, o número de sementes por vagem e de vagens por planta aumentaram com a redução na população de plantas. Na fase do enchimento de grãos, a redução do espaçamento entre linhas de cultivo aumentou a massa seca da parte aérea das plantas. A cultivar de feijoeiro, BR-FEPAGRO 44 - Guapo brilhante, apresenta elevada plasticidade dos componentes do rendimento, havendo compensação no rendimento de grãos nas menores populações de plantas com aumento da produção por planta.The objective of this experiment was to evaluate the effect of different plant populations and row spacing on dry matter accumulation, grain yield and yield components of irrigated drybean. The experiment was conducted during the 1997/98 growing season in the experimental field of the Rural Engineering Department of the Federal University of Santa Maria, Santa Maria - RS, Brayl. The cultivar BR-FEPAGRO 44 - Guapo brilhante, (type II) was submitted to three plant populations (175, 250 and 325 thousand plants há-1) and three row spacing (35, 50 and 65cm). A factorial completely randomized design was used with four replications. Sprinüer irrigations were appiied when maximum crop evapofranspiration, determined based on class A evaporation pan, indicated na accumulated value of 25mm. Results demonstrated that the different plant populations and row spacing did not affect grain yield and grain weight. However, the number ofseeds per legume and legumes per plant increased as plant population decreased. The reduction in row spacing increased shoot dry matter during grain filling period. The cultivar BR-FEPAGRO 44 - Guapo brilhante presented great plasticity of grain yield components mainly because the reduction in plant population resulted in higher grain yield of individual plants.

O experimento foi conduzido com o objetivo de avaliar variações no índice de área foliar, altura das plantas, número de nós, comprimento dos entrenós na haste principal e altura das vagens em relação à superfície do solo do feijoeiro irrigado e cultivado em diferentes populações de plantas e espaçamentos entre linhas de cultivo. O experimento foi conduzido no ano agrícola 1997/98, em área experimental do Departamento de Engenharia Rural da Universidade Federal de Santa Maria, Santa Maria, RS. A cultivar de feijão preto BR-FEPAGRO 44 - Guapo brilhante, de crescimento indeterminado (tipo II), foi cultivada em três populações de plantas (175, 250 e 325 mil plantas há-1) e três espaçamentos entre linhas de cultivo (35, 50 e 65cm). Utilizou-se o delineamento experimental inteiramente casualizado, bifatorial, com quatro repetições. Irrigações por aspersão foram aplicadas quando a evapotranspiração máxima da cultura, estimada com base na evaporação do tanque classe "A", indicava um valor acumulado de 25mm. Os resultados demonstraram que o aumento da população de plantas ocasionou aumento no índice de área foliar durante a fase de crescimento vegetativo da cultura, sendo que na fase reprodutiva, o índice de área foliar foi afetado pelo espaçamento entre as linhas de cultivo. A área foliar, a altura de plantas e o número de nós na haste principal aumentaram com a redução na população de plantas. A altura da extremidade da primeira vagem das plantas em relação ao solo apresentou comportamento quadrático com o aumento na população de plantas. Os diferentes espaçamentos e populações de plantas não afetaram o comprimento dos entrenós na haste principal das plantas.The objective of this experiment was to evaluate changes in leaf area index, plant height, number of nodes, inter-node length and legumes height above soil surface of drybean plants cultivated in different plant populations and row spacings. The experiment was conducted during 1997/98 growing season in the experimental field of the Rural Engineering Department ofthe Federal University of Santa Maria, Santa Maria - RS, Brazil. The drybean cultivar BR-FEPAGRO 44 - Guapo brilhante, (type II) was submitted to three plant populations (175, 250 and 325 thousand plants há-1) and three row spacing (35, 50 and 65cm). A completely randomized design, factorial, was used with four replications. Sprinkler irrigations were applied when maximum crop evapotranspiration, determined based on class "A" evaporation pan, indicated an accumulated value of 25mm. Results demonstrated that the increase in plant population increased leaf area index during the vegetative period. However, during the reproductive period the leaf area index was more affected by row spacing. The leaf area of individual plants, plant height and the number of nodes increased as plant population decreased. The legume height above soil surface presented a quadratic response in relation to plant population. The inter-node length was not affected by the different plant population and row spacing tested.

Highlights: [•] We evaluated the effect of management practices on establishment of Italian ryegrass. [•] We tested pasture's ability to re-establish following a year without seed production. [•] Grazing intensity is the first factor affecting subsequent pasture establishment. [•] Pasture establishment by self-seeding relies on the annual seed replacement. [•] Grazing must be managed to allow sufficient reproductive tiller production. [ABSTRACT FROM AUTHOR]

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Highlights: [•] Natural enemies of insect pests in brassica vegetable crops are numerous in China. [•] Major parasitoids have great potential to suppress pest populations. [•] The role of natural enemies can be promoted by the use of selective insecticides. [•] The strategy of conservation biological control can reduce insecticide input. [•] Several successful brassica IPM practices have enhanced conservation biological control. [ABSTRACT FROM AUTHOR]

Soil nematode communities were studied in four differents crop systems at the Integrated System of Agroecological Production. Soil samples were collected at four-month intervals during one year, with three replications for each location. Nematode communities were measured by the following parameters: family richness, Shannon-Weaner′s index, Simpson′s index, trophic diversity (T) and dominance index (Ig). These data were submitted to ANOVA statistical analysis at 5% level of Tukey′s test. The population of bacterivores and herbivore nematodes was high in all areas. Omnivores were found in lower abundance in all systems. The highest diversity of nematode families was found on pasture. In forests, the values of richness and abundance were always lower but constant in time, suggesting an ecosystem of higher stability. Soil management induced the proliferation of bacterivores usually associated with higher decomposition rates of organic matter. Herbivores and bacterivores were dominant in all systems, suggesting it is important to have high root (for pasture) or high decomposition rates (for horticulture system). The relative distribution of trophic groups of soil nematodes proved to be a good way to determine the level of perturbation of ecosystems. [ABSTRACT FROM AUTHOR]

Abstract: Weed suppression and green manure effects are two potential benefits of including a legume cover crop in vegetable cropping systems. A requirement for using autumn established cover crops, however, is to find species and cultivars adapted to the local climate and latitude. Knowledge about optimal sowing time is also needed. The objective of this study was to monitor the crop behavior, with special emphasis on winter survival and biomass production, of winter annual and biennial legumes sown at various times of year before the establishment of vegetables in the subsequent year. Low growing species/cultivars, including annual medics (Medicago spp.) and subterranean clover (T. subterraneum L. cv. Denmark), which may be suitable when vegetables transplanted directly into a senesced living mulch, showed poor winter survival and are thus not recommended for our climate. Taller species, including hairy vetch (Vicia villosa Roth.), crimson clover (T. incarnatum L.) and yellow sweetclover [Melilotus officinalis (L.)], which require mowing before the establishing of vegetables, showed much better winter survival and biomass production the subsequent year. The study showed however, that the suitability of these cover crops depends on cultivar, sowing time and climate region. The mineralization study showed that hairy vetch and white clover were rich in N and showed a high N mineralization rate. Mineralization of N from crimson clover and yellow sweetclover was lower. We conclude that hairy vetch, crimson clover and yellow sweetclover, used in the proper way, have potential as cover crops under northern conditions. [Copyright &y& Elsevier]

This paper aims to identify the land-use factors benefiting sustainable land management in terms of environmental conservation. For evaluating the impacts of land use on the environment, the following parameters were used: chemical fertiliser and pesticide use, land-use structure and diversity. The farmers' income, land tenure and farming scale were selected for their influence on agricultural sustainability. The analysis shows a rapid increase in use of chemical fertiliser and pesticide in the past 40 years, and an observable increase in land-use diversity. The amount of chemical fertiliser used per unit area in large-scale farming was lower than that at small scales, but large-scale farming consumes more pesticide than small-scale farming. A significant negative correlation was observed between the proportions of the holdings possessing land and the holdings using the chemical fertiliser. In order to achieve sustainable agriculture, it is necessary to manage crop systems and land use towards selecting new strains and varieties of crops and fruits with a lower demand for chemical fertiliser and a higher resistance to disease and pests, balancing large- and small-scale farming, and ensuring land tenure and economic incentives. [ABSTRACT FROM AUTHOR]

Abstract: Nitrous oxide (N2O) emissions resulting from Chinese vegetable production were measured. A site in suburban Nanjing (East coast; Jiangsu Province) was monitored from November 2001 to January 2003, in which five consecutive vegetable crops were sown. The crops consisted of radish, baby bok choy, lettuce, second planting of baby bok choy, and finally celery. Results suggested that N2O emission events occur in pulses. The average N2O-N flux for all five crops was 148±9μgNm−2 h−1 and the average emission rate was 12±0.7kgNha−1. The average seasonal emission fluxes ranged from 37μgNm−2 h−1 in the radish plot to 300μgNm−2 h−1 in the celery plot. The celery field produced the greatest cumulative emission of 5.8kgNha−1 while the baby bok choy field had the lowest rate of 0.96–1.0kgNha−1. In total, 0.73% of applied fertilizer N was emitted as N2O-N as a whole. The lettuce field had the largest emission factor of 2.2%. Results indicate that emissions from vegetable field are a potential source of national N2O inventory. Temporal variation is much greater than spatial variation and the corresponding CV averaged 115% and 22%, respectively. Under the same total sampling quantity, increasing sampling frequency is more important than increasing spatial replicates. [Copyright &y& Elsevier]