Enhancing efficiency of fertilizer N use in rice-wheat systems of Indo-Gangetic Plains by intercropping Sesbania aculeata in direct seeded upland rice for green manuring

A field experiment was conducted on rice-wheat system at Modipuram, India in Typic Ustochrept. Sesbania was intercropping in direct seeded rice for green manuring with 3 levels of Urea N (i.e., O, 60, 120 and 180 KgNha(-1)). Sesbania was turned in the soil after 30 days of sowing. Grain yields of rice and wheat were significantly greater in plots receiving green manuring than that without green manuring. In general, advantages of green manuring were greater at low levels of N than at higher levels, and the residual effect of green manuring on succeeding wheat was very small.     

Effect of organic manuring on the activities of the enzymes hydrolysing sucrose and urea and on soil aggregation

Summary The effect of organic manuring with farm-yard manure, maize stalk, and Pongamia cake (Pongamia glabra) at 1 per cent organic carbon level on the activities of the enzymes hydrolysing sucrose and urea, in relation to changes in soil microbial populations and on soil reaction and aggregation was investigated in a red sandy loam soil. Farm yard manuring did not alter the invertase activity to any appreciable extent; but both maize stalk and Pongamia cake enhanced the invertase activity of the soil significantly. While appreciable increase in urease activity was also observed due to the application of both maize stalk and Pongamia cake, the latter treatment maintained the soil urease activity at a higher level.No definite correlation could be observed between the changes in the microbial populations and the enzyme activities during the incubation period. The pH of the soil treated with Pongamia cake was considerably increased. Organic manuring significantly increased aggregation of soil particles and maximum soil aggregation was observed in the case of maize stalk application.     

Combining functional weed ecology and crop stable isotope ratios to identify cultivation intensity: a comparison of cereal production regimes in Haute Provence,France and Asturias,Spain

This investigation combines two independent methods of identifying crop growing conditions and husbandry practices—functional weed ecology and crop stable carbon and nitrogen isotope analysis—in order to assess their potential for inferring the intensity of past cereal production systems using archaeobotanical assemblages. Present-day organic cereal farming in Haute Provence, France features crop varieties adapted to low-nutrient soils managed through crop rotation, with little to no manuring. Weed quadrat survey of 60 crop field transects in this region revealed that floristic variation primarily reflects geographical differences. Functional ecological weed data clearly distinguish the Provence fields from those surveyed in a previous study of intensively managed spelt wheat in Asturias, north-western Spain: as expected, weed ecological data reflect higher soil fertility and disturbance in Asturias. Similarly, crop stable nitrogen isotope values distinguish between intensive manuring in Asturias and long-term cultivation with minimal manuring in Haute Provence. The new model of cereal cultivation intensity based on weed ecology and crop isotope values in Haute Provence and Asturias was tested through application to two other present-day regimes, successfully identifying a high-intensity regime in the Sighisoara region, Romania, and low-intensity production in Kastamonu, Turkey. Application of this new model to Neolithic archaeobotanical assemblages in central Europe suggests that early farming tended to be intensive, and likely incorporated manuring, but also exhibited considerable variation, providing a finer grained understanding of cultivation intensity than previously available.     

Enhancing the fish production potential of Lake Victoria papyrus wetlands,Kenya, using seasonal flood-dependent ponds

We present the findings of a participatory experiment on integrated aquaculture-agriculture systems (Fingerponds) at the Lake Victoria wetlands, Kenya. Fingerponds are flood-based lacustrine or floodplain wetland fishponds. The aim of the study was to explore, within a wetland/floodplain interface environment, the potential of semi-intensive fish production to enhance the wetland fishery and protect the natural ecosystem from wide-scale, destructive encroachment. The ponds were stocked naturally by flood water. After flood recession, livestock manure was added to the ponds and the effects of manuring on water and sediment quality and fish yields were studied. Manuring had positive effects on the nitrogen, phosphorous and chlorophyll a concentrations of the pond water. Regression analysis results indicated that site, manuring and environmental and climatic variables explained 58–70% of the variation in dissolved nitrogen and phosphorous, and 71% of the variation in chorophyll a. Manuring enhanced the total phosphorus concentration in the sediment but it only had marginal effects on total nitrogen. Although the net fish yields were highly variable between sites and seasons, ranging from 402 to 1069 kg ha⁻¹, the data showed that manuring was advantageous. The duration of the culture period, site variability and manuring explained 82% of the variation in fish yields. We conclude that Fingerponds fertilized with livestock manure from abutting riparian subsistence agriculture can improve fish production, enhance food diversity and security and contribute to more efficient use of papyrus wetlands for food production. This in turn may reduce large-scale conversion of wetlands to agriculture.     

稻田免耕和稻草还田对土壤腐殖质和微生物活性的影响

为了阐明免耕和稻草还田土壤固碳机制,研究了无稻草还田免耕（NT）、无稻草还田常耕（CT）、稻草还田免耕（NTS）和稻草还田常耕（CTS）对水稻不同生育期不同土层（0—5,5—12,12—20cm）土壤腐殖质形态、含量及微生物活性的影响。结果表明,免耕（NT和NTS）处理显著增加0—5 cm土层土壤游离松结态、联结态和稳紧结态腐殖质含量和游离松结态腐殖质占总腐殖质的比例,且免耕对土壤各结合态腐殖质含量的影响程度有随生育期的推后而增加的趋势;5—12cm和12—20cm土层土壤各结合态腐殖质含量和0—20cm各土层微生物活性有减少趋势;在水稻分蘖期免耕对微生物活性影响很弱,在水稻拔节—灌浆期免耕处理显著降低5—12 cm土层土壤微生物活性,相反,免耕却增加水稻成熟期0—5 cm土层的微生物活性;另一方面,稻草还田（CTS和NTS）显著提高土壤各结合态腐殖质含量,尤其是0—5 cm土层、游离松结态腐殖质及水稻生育后期;CTS处理显著增加分蘖期—孕穗期0—20 cm土层的呼吸强度,而稻草还田显著增加孕穗期—成熟期0—5cm土层的纤维素分解强度。可见,通过增加土壤腐殖质含量和各结合态腐殖质含量并改变微生物活性免耕有利于表土层碳的固定作用,而免耕与稻草还田相结合更有利于土壤碳的积累。     

Evaluating second year cropping on jhum fallows in Mizoram,north-eastern India—Phytomass dynamics and primary productivity

Cropping on jhum fallows in north-eartern India is predominantly done for one year in a jhum cycle. If second year cropping is done, expanse of the forest land required for slashing and burning could be reduced significantly. We tested this hypothesis in a young (6 yr) and an old (20 yr) jhum fallow. We also evaluated if the productivity during second year cropping could be alleviated by auxiliary measures such as tilling the soil or application of fertilizers (chemical or farm-yard manure or both in combination). The results demonstrate that the ecosystem productivity (total dry matter production) and economic yield (rice grain production) decline with shortening of jhum cycle. Second year cropping causes a further decline in ecosystem productivity in old jhum field, but not in young jhum field. Economic yield from second year cropping in its traditional form (without any fertilizer treatment) is not much lower than that in the first year, and can be improved further by manuring the soil. Tilling of soil improves neither ecosystem productivity nor economic yield. Different fertilization treatments respond differently; while inorganic manuring enhances ecosystem productivity, a combination of inorganic and organic manuring improves economic yield     

Green manure effect on the ability of native and inoculated soil bacteria to mobilize zinc for wheat uptake (Triticum aestivum L.)

Plant and Soil - Green manuring can increase the plant available fraction of zinc (Zn) in soil, making it a potential approach to increase wheat Zn concentrations and fight human Zn deficiency. We...     

Morphological and ecophysiological root and leaf traits in ectomycorrhizal,arbuscular-mycorrhizal and non-mycorrhizal Alnus incana seedlings

Plant and Soil - Green manuring can suppress crop diseases and change soil microbial communities, but the functional significances of changes in soil microbial communities are unclear. Effects of...     

Factors influencing infection of the tomato by Verticillium albo-atrum. II

Tomato plants receiving adequate supplies of mineral nutrient acquired great resistance to infection by Verticillium albo-atrum if the leaf-shoot ratio was reduced; this effect is attributed to reduction in carbohydrate content of the host. Wide variation in potash manuring did not affect susceptibility of tomatoes to Verticillium .     

小麦品种的耐肥性与光合作用

本试验以耐肥性不同的三个冬小麦品种为试材,研究了品种的耐肥性与光合作用的关系。结果表明,旗叶的光合速率顺序为: 泰山一号(中度耐肥)>济南13(高度耐肥)>昌乐5号(不耐肥)。光合速率的绝对值虽因不同年度间环境条件的不伺而有所变动,但品种间的差别则保持相对稳定。增施氮肥,能使昌乐5号的光合速率明显降低,而泰山—和济南13的光合速率则因增施氮肥受到显著的促进。     

小麦品种的耐肥性与光合作用

本试验以耐肥性不同的三个冬小麦品种为试材,研究了品种的耐肥性与光合作用的关系。结果表明,旗叶的光合速率顺序为;泰山一号(中度耐肥)>济南13(高度耐肥)>昌乐5号(不耐肥)。光合速率的绝对值虽因不同年度间环境条件的不同而有所变动,但品种间的差别则保持相对稳定。增施氮肥,能使昌乐5号的光合速率明显降低,而泰山一号和济南13的光合速率则因增施氮肥受到显著的促进。     

Studies in the physiology of the onion plant; further experiments on the effects of storage temperature and other factors on onions grown from sets

A wide range of factorial experiments at Wisley on onions grown from sets included combinations of the factors: storage of sets at high and low temperatures during the winter, variety, set size, set planting date and nitrogen manuring. Bolting, yield and ripening data are recorded. One experiment was repeated in Scotland and Northumberland where early ripening was expected to be more important than at Wisley. In general, all the factors enumerated except nitrogen manuring had large effects on bolting and yield, and storage temperature had a large effect on the time of ripening. Varieties can be selected such that large sets may be used without appreciable loss by bolting and maximum yield thus secured. Storage temperatures of from 20 to 24° C., applied for about 14 weeks from October onwards, can be used to control bolting and to increase the yield even of non-bolting strains by delaying ripening and so extending the growth period. Storage at 24° C. is more effective in preventing bolting than the lower temperatures, but 20° C. is probably more effective in delaying ripening. High-temperature storage is probably unsuitable for sets to be planted in the north and west of Great Britain because of the difficulty of ripening the bulbs. For these districts low-bolting strains are therefore essential. Storage at o° C. gives only a partial control of bolting and has no effect on ripening. Late planting of sets, although very effective in controlling bolting, results in a substantial loss of yield and, therefore, is not a practical measure. Nitrogen manuring had practically no effect on yield and could not be used to prevent the loss of yield caused by late planting.     

Role of manuring in control of root-rot of guar (Cyamopsis psoralioides dc.) and wilt of gram (Cicer arietinum L.) caused by sclerotium rolfsii Sacc.

Summary Root-rot of guar (Cyamopsis psoralioides DC.) and wilt of gram (Cicer arietinum L.) caused bySclerotium rolfsii Sacc. are important diseases in the province of Uttar Pradesh in India. The two diseases were significantly reduced by manuring the garden soil with municipal farm manure (compost). Disease incidence in root-rot of guar was 71.9 % in the untreated garden soil. When the soil was mixed with double the amount of compost, only 54.7 % root-rot was observed. Similarly, 82.1 % wilt was noticed in gram in untreated garden soil and addition of compost in 1:1 ratio (soil:compost) significantly reduced the disease to 64.3 %. Heavy manuring is recommended for controlling the two diseases to a considerable extent.A part of Ph. D. thesis submitted by the senior author to Agra University, Agra, India.     

Meteorological and Hydrographical Features of Vellayani Lake,Kerala, India

Meteorological, physical and chemical parameters of Vellayani Lake, Kerala, India, have been analysed for twelve months (August 1980 to July 1981), the topography of the lake is described, and correlation coefficients were calculated between meteorological and hydrographical parameters. The results indicate that the lake can be converted into a productive aquafarm by means of slight manuring.     

Organic and mineral fertilization, respectively, increase and decrease the development of external mycelium of arbuscular mycorrhizal fungi in a long-term field experiment

Effects of long-term mineral fertilization and manuring on the biomass of arbuscular mycorrhizal fungi (AMF) were studied in a field experiment. Mineral fertilization reduced the growth of AMF, as estimated using both measurements of hyphal length and the signature fatty acid 16:1ω5, whereas manuring alone increased the growth of AMF. The results of AMF root colonization followed the same pattern as AMF hyphal length in soil samples, but not AMF spore densities, which increased with increasing mineral and organic fertilization. AMF spore counts and concentration of 16:1ω5 in soil did not correlate positively, suggesting that a significant portion of spores found in soil samples was dead. AMF hyphal length was not correlated with whole cell fatty acid (WCFA) 18:2ω6,9 levels, a biomarker of saprotrophic fungi, indicating that visual measurements of the AMF mycelium were not distorted by erroneous involvement of hyphae of saprotrophs. Our observations indicate that the measurement of WCFAs in soil is a useful research tool for providing information in the characterization of soil microflora.     

Factors affecting the horizontal patchiness of coastal Antarctic seawater bacteria

Summary Previous Antarctic studies have pointed out the ecological importance of ornithogenic soils. However, few data exist to determine the impact of the bird's manuring on surrounding seawater microbial populations. In order to evaluate the influence of birds manuring, the relationships between the spatial distributions of seawater bacterial microflora and some related biological (chlorophyll pigments) and physicochemical (seston, NH₄ ⁺ & NO₃ ^–) parameters were studied during the Antarctic summer 1988 in the Terre Adelie land area. The clearly decreasing gradient from the shore towards the open sea previously reported for bacterial microflora (from 10⁴ to 1 CFU ml^–1 for heterotrophic bacteria and from 10⁵ to 5.010³ cells ml^–1 for total bacteria) was also observed for organic and mineral nutrients (from 1.09 mg Cl^–1 to 0.1 mg Cl^–1 for POC and from 196 to 17 mole l^–1 for NH ₄ ⁺ ) but not for chlorophyll pigments. The absence of any observable phytoplankton enrichment in the coastal area suggests a direct interaction between the birds manuring and the bacterial seawater microflora.     

Evaluating second year cropping on jhum fallows in Mizoram, north-eastern India: Energy and economic efficiencies

Energy and economic efficiencies were evaluated on young (6 year) and old (20 year) jhum fields in Mizoram, north-eastern India during second year of cropping, and were compared with those in the first year. The effect of auxiliary measures such as tilling the soil or application of fertilizers (chemical or farm-yard manure or both in combination) was also examined on energy and economic efficiencies. The results indicated that traditional jhum cultivation is labour intensive and energy efficient, producing almost 15–20 times of energy invested. Energy and economic efficiencies decline with shortening of jhum cycle. These efficiencies decline further from first to second year of cropping. Tilling is not useful to improve either energy or economic efficiency. Fertilizer application, which is though profitable from the point of view of economic efficiency, is highly energy inefficient. Application of fertilizers during second year cropping can be encouraged. Organic manuring may be a better option than others to alleviate energy efficiency. However, a combination of organic and inorgamic manuring could be the best option to enhance economic efficiency.     

Vegetation Changes in a Wet Meadow Complex during the Past Half-Century

Repeated vegetation maps and phytosociological relevés recorded in the 1950s and again from 1984 to 2006 in a wet meadow complex near the town of T?eboň, in the southern part of the Czech Republic, central Europe were compared. The following trends were evident: original vegetation zones disappeared, as well as vegetation typical of less intensively used sites, i.e., short-sedge marshes and Deschampsia cespitosa meadows. Instead, stands with Phalaris arundinacea, Urtica dioica, Elytrigia repens, and species-poor Alopecurus pratensis meadows, as well as woody species, expanded as a result of either too intensive use (cutting, manuring) or abandonment. The number of 46 meadow and marsh species recorded in 1956 in repeated relevés was reduced to one-third, while ruderal and weedy species increased from zero to 22, thus surpassing the meadow and marsh species being now more numerous than the former ones. The large degradation that started in the late 1970s continues, with there being no chance of recovery unless the present management regime stops manuring and implements appropriate regular cutting once or twice a year.     

Plant communities along environmental gradients of high‐arctic mires in Sassendalen,Svalbard

Abstract. The wet to moist bryophyte‐dominated vegetation of Sassendalen, Svalbard, was classified into seven communities. These communities were grouped into (1) Cardamino nymanii‐Saxifragion foliolosae marsh; (2) Caricion stantis fen; (3) Luzulion nivalis snowbed – including manured vegetation corresponding to moss tundras. All communities have a basically arctic distribution. Marshes are developed in habitats with a water table above the bryophyte vegetation surface and fens on sites with a water table level high above the permafrost but below the bryophyte surface. Moss tundras normally have no standing water table, but in Sassendalen they have a low water table due to their development on less steep slopes than in their normal habitat near bird cliffs. CCA confirms that the standing water level is the prime differentiating factor between the alliances, while aspect favourability and permafrost depth differentiate between the fen communities and temporary desiccation is important for the Catoscopium nigritum community. Carex subspathacea is a characteristic fen species in the absence of other Carex species dominating elsewhere in the Arctic. Arctic marshes are linked to an extremely cold environment. They have a very low species diversity with a few species dominating; Arctophila fulva, Pseudocalliergon trifarium, Scorpidium scorpioides and Warnstorfia tundrae are character species. Moss tundra as defined here appears to be restricted to Svalbard and, probably, neighbouring Novaya Zemlya. This may be due to the absence of rodents and the high seabird density, which is related to the mild sea currents reaching further to the north here and which implies manuring of surrounding ecosystems. Manuring in a very cold environment produces moss carpets with a thin active layer and accumulation of thick peat layers without a standing water level. In Sassendalen the role of arctic seabirds is replaced by Svalbard reindeer which are nonmigratory and are concentrated to favourable grazing areas where their manuring effect is intense. Their long‐term manuring effect probably explains the occurrence of moss tundras in this weakly rolling landscape where seabird colonies are absent.     

灵香草生物学及栽培生态学特性的研究

本文用3年定点观测资料,分析了灵香草植株生长、干物质积累的进程,定量地论述了灵香草生长发育与光、温、水等生态因子之间的关系,总结了灵香草的高产栽培措施,对灵香草的引种、施肥、管理、抚育、采收等具有参考价值,试验观测方法也可供研究特种经济作物时借鉴。