Development of Zero Water Exchange Shrimp Culture System Integrated With Bioremediation of Detritus and Ammonia- Nitrogen

Aquaculture is one of the fastest growing food sectors in the world. Amongst the various branches of aquaculture, shrimp culture has expanded rapidly across the globe because of its faster growth rate, short culture period, high export value and demand in the International market. Indian shrimp farming has experienced phenomenal development over the decades due to its excellent commercial viability. Farmers have adopted a number of innovative technologies to improve the production and to maximize the returns per unit area. The culture methods adopted can be classified in to extensive, modified extensive and semi intensive based on the management strategies adopted in terms of pond size, stocking density, feeding and environmental control. In all these systems water exchanges through the natural tidal effects, or pump fed either from creek or from estuaries is a common practice. In all the cases, the systems are prone to epizootics due to the pathogen introduction through the incoming water, either brought by vectors, reservoir hosts, infected tissue debris and free pathogens themselves. In this scenario, measures to prevent the introduction of pathogen have become a necessity to protect the crop from the onslaught of diseases as well as to prevent the discharge of waste water in to the culture environment.The present thesis deals with Standardization of bioremediation technology for zero water exchange shrimp culture system

A study of the Coconut Economy of Kerala, 1956-1983

In the introductory chapter of the dissertation the importance of coconut cultivation for the economy of Kerala State has been highlighted. The second and third chapters contain analysis of changes in area, production and productivity of coconut cultivation in the state. The use of modern agricultural practices by coconut farmers is analysed in chapter IV. Cost of production and profitability are dealt with in chapter V, while the issues relating to coconut prices and marketing are presented in chapter VI. Diseases affecting coconut is the theme covered under chapter VII , Summary and conclusions are provided at the end.

Impact of Agricultural Credit in the.Agricultural Development of Kuttanad

Introduction of agrarian reforms and introduction of new technology increased dependence on casual labourers. High labour absorption in the subsistence agriculture and increased price of input resulted in high cost of cultivation. Price of paddy did not rise correspondingly. As a result subsistence economy's future is bleak. The purpose of the _study is to examine these arguments and related issues with the help of empirical evidence from Kuttanad. The credit schemes are designed to help farmers to earn higher incomes by larger output brought either by an increase in area or by an improvement in yield rates or both. It is difficult to isolate the impact of agricultural credit on agricultural development. Because agricultural development is the combined effect of all inputs. The specific .criteria selected for analysing the impact of agricultural icredit are how increased supply of credit would bring changes ‘in capital formation, agrarian relations, informal lending and its cost and the changes in area, output, introduction of new technology, income, savings and employment of farm households.

A Study on Futures Trading in Commodities With Special Reference to Rubber

Futures trading in Commodities has three specific economic functions viz. price discovery, hedging and reduction in volatility. Natural rubber possesses all the specifications required for futures trading. Commodity futures trading in India attained momentum after the starting of national level commodity exchanges in 2003. The success of futures trading depends upon effective price risk management, price discovery and reduced volatility which in turn depends upon the volume of trading. In the case of rubber futures market, the volume of trading depends upon the extent of participation by market players like growers, dealers, manufacturers, rubber marketing co-operative societies and Rubber Producer’s Societies (RPS). The extent of participation by market players has a direct bearing on their awareness level and their perception about futures trading. In the light of the above facts and the review of literature available on rubber futures market, it is felt that a study on rubber futures market is necessary to fill the research gap, with specific focus on (1) the awareness and perception of rubber futures market participants viz. (i) rubber growers, (ii) dealers, (iii) rubber product manufacturers, (iv) rubber marketing co-operative societies and Rubber Producer’s Societies (RPS) about futures trading and (2) whether the rubber futures market is fulfilling the economic functions of futures market viz. hedging, reduction in volatility and price discovery or not. The study is confined to growers, dealers, rubber goods manufacturers, rubber marketing co-operative societies and RPS in Kerala. In order to achieve the stated objectives, the study utilized secondary data for the period from 2003 to 2013 from different published sources like bulletins, newsletters, circulars from NMCE, Reserve Bank of India (RBI), Warehousing Corporation and traders. The primary data required for this study were collected from rubber growers, rubber dealers, RPS & Rubber Marketing Co-operative Societies and rubber goods manufacturers in Kerala. Data pertaining to the awareness and perception of futures trading, participation in the futures trading, use of spot and futures prices and source of price information by dealers, farmers, manufacturers and cooperative societies also were collected. Statistical tools used for analysis include percentage, standard deviation, Chi-square test, Mann – Whitney U test, Kruskal Wallis test, Augmented Dickey – Fuller test statistic, t- statistic, Granger causality test, F- statistic, Johansen co – integration test, Trace statistic and Max –Eigen statistic. The study found that 71.5 per cent of the total hedges are effective and 28.5 per cent are ineffective for the period under study. It implies that futures market in rubber reduced the impact of price risks by approximately 71.5 per cent. Further, it is observed that, on 54.4 per cent occasions, the futures market exercised a stabilizing effect on the spot market, and on 45.6 per cent occasions futures trading exercised a destabilizing effect on the spot market. It implies that elasticity of expectation of futures market in rubber has a predominant stabilizing effect on spot prices. The market, as a whole, exhibits a bias in favour of long hedges. Spot price volatility of rubber during futures suspension period is more than that of the pre suspension period and post suspension period. There is a bi-directional association-ship or bi-directional causality or pair- wise causality between spot price and futures price of rubber. From the results of the hedging efficiency, spot price volatility, and price discovery, it can be concluded that rubber futures market fulfils all the economic functions expected from a commodity futures market. Thus in India, the future of rubber futures is Bright…!!!

Decomposition of and nutrient release from ruminant manure on acid sandy soils in the Sahelian zone of Niger, West Africa

In ago-pastoral systems of the semi-arid West African Sahel, targeted applications of ruminant manure to the cropland is a widespread practice to maintain soil productivity. However, studies exploring the decomposition and mineralisation processes of manure under farmers' conditions are scarce. The present research in south-west Niger was undertaken to examine the role of micro-organisms and meso-fauna on in situ release rates of nitrogen (N), phosphorus (P) and potassium (K) from cattle and sheep-goat manure collected from village corrals during the rainy season. The results show tha (1) macro-organisms played a dominant role in the initial phase of manure decomposition; (2) manure decomposition was faster on crusted than on sandy soils; (3) throughout the study N and P release rates closely followed the dry matter decomposition; (4) during the first 6 weeks after application the K concentration in the manure declined much faster than N or P. At the applied dry matter rate of 18.8 Mg ha^-1, the quantities of N, P and K released from the manure during the rainy season were up to 10-fold larger than the annual nutrient uptake of pearl millet (Pennisetum glaucum L.), the dominant crop in the traditional agro-pastoral systems. The results indicate considerable nutrient losses with the scarce but heavy rainfalls which could be alleviated by smaller rates of manure application. Those, however, would require a more labour intensive system of corralling or manure distribution.

Phosphorus placement an acid arenosols of the West African Sahel

Phosphorus (P) deficiency is a major constraint to pearl millet (Pennisetum glaucum L.) growth on acid sandy soils of the West African Sahel. To develop cost-effective fertilization strategies for cash poor farmers, experiments with pearl millet were conducted in southwestern Niger. Treatments comprised single superphosphate hill-placed at rates of 1, 3, 5 or 7 kg P ha^−1 factorially combined with broadcast P at a rate of 13 kg ha^−1. Nitrogen was applied as calcium ammonium nitrate at rates of 30 and 45 kg ha^−1. At low soil moisture, placement of single superphosphate in immediate proximity to the seed reduced seedling emergence. Despite these negative effects on germination, P placement resulted in much faster growth of millet seedlings than did broadcast P. With P application, potassium nutrition of millet was improved and seedling nitrogen uptake increased two- to three-fold, indicating that nitrogen was not limiting early millet growth. Averaged over the 1995 and 1996 cropping seasons, placed applications of 3, 5 and 7 kg P ha^−1 led to 72%, 81% and 88% respectively, of the grain yield produced by broadcasting 13 kg P ha^−1. Nitrogen application did not show major effects on grain yield unless P requirements were met. A simple economic analysis revealed that the profitability of P application, defined as additional income per unit of fertilizer, was highest for P placement at 3 and 5 kg ha^−1.

Cereal/legume rotation effects on rhizosphere bacterial community structure in West African soils

The increased use of cereal/legume crop rotation has been advocated as a strategy to increase cereal yields of subsistence farmers in West Africa, and is believed to promote changes in the rhizosphere that enhance early plant growth. In this study we investigated the microbial diversity of the rhizoplane from seedlings grown in two soils previously planted to cereal or legume from experimental plots in Gaya, Niger, and Kaboli, Togo. Soils from these legume rotation and continuous cereal plots were placed into containers and sown in a growth chamber with maize (Zea mays L.), millet (Pennisetum glaucum L.), sorghum (Sorghum bicolor L. Moench.), cowpea (Vigna unguiculata L.) or groundnut (Arachis hypogaea L.). At 7 and 14 days after sowing, 16S rDNA profiles of the eubacterial and ammoniaoxidizing communities from the rhizoplane and bulk soil were generated using denaturing gradient gel electrophoresis (DGGE). Community profiles were subjected to peak fitting analyses to quantify the DNA band position and intensities, after which these data were compared using correspondence and principal components analysis. The data showed that cropping system had a highly significant effect on community structure (p <0.005), irrespective of plant species or sampling time. Continuous cereal-soil grown plants had highly similar rhizoplane communities across crop species and sites, whereas communities from the rotation soil showed greater variability and clustered with respect to plant species. Analyses of the ammonia-oxidizing communities provided no evidence of any effects of plant species or management history on ammonia oxidizers in soil from Kaboli, but there were large shifts with respect to this group of bacteria in soils from Gaya. The results of these analyses show that crop rotation can cause significant shifts in rhizosphere bacterial communities.

Changes in amino acid enantiomers and microbial performance in soils from a subtropical mountain oasis in Oman abandoned for different periods

An important feature of maintaining the agricultural stability in millennia-old mountain oases of northern Oman is the temporary abandonment of terraces. To analyse the effects of a fallow period on soil microbial performance, i.e. microbial activity and microbial biomass, samples of eight terrace soils abandoned for different periods were collected in situ, assigned to four fallow age classes and incubated for 30 days in the laboratory after rewetting. The younger fallow age classes of 1 and 5 years were based on the records of the farmers’ recollections, the two older fallow age classes of 10–20 and 25–60 years according to the increase in the D -to- L ratio of valine and leucine enantiomers. The increase in these two ratios was in agreement with that of the D -to- L ratio of lysine. The strongest relationship was observed between the increase in the D -to- L ratio of lysine and the decrease in soil microbial biomass C. However, the most stringent coherence between the increase in fallow age and soil properties was revealed by the decreases in cumulative respiration and net N mineralisation rates with decreasing availability of substrate to soil microorganisms. During the 30-day incubation following rewetting, relative changes in microbial activity (respiration and net N mineralisation) and microbial biomass (C and N)indices were similar in the eight terrace soils on a fallow age-class-specific level, indicating that the same basic processes occurred in all of the sandy terrace soils investigated.

Low-altitude aerial photography for optimum N fertilization of winter wheat on the North China Plain

Previous research has shown that site-specific nitrogen (N) fertilizer recommendations based on an assessment of a soil’s N supply (mineral N testing) and the crop’s N status (sap nitrate analysis) can help to decrease excessive N inputs for winter wheat on the North China Plain. However, the costs to derive such recommendations based on multiple sampling of a single field hamper the use of this approach at the on-farm level. In this study low-altitude aerial true-color photographs were used to examine the relationship between image-derived reflectance values and soil–plant data in an on-station experiment. Treatments comprised a conventional N treatment (typical farmers’ practice), an optimum N treatment (N application based on soil–plant testing) and six treatments without N (one to six cropping seasons without any N fertilizer input). Normalized intensities of the red, green and blue color bands on the photographs were highly correlated with total N concentrations, SPAD readings and stem sap nitrate of winter wheat. The results indicate the potential of aerial photography to determine in combination with on site soil–plant testing the optimum N fertilizer rate for larger fields and to thereby decrease the costs for N need assessments.

A survey of wheat landraces in Oman

Little is known about the diversity of wheat (Triticum spp.) in Oman. Therefore, a survey was conducted in northern Oman to collect landraces of Triticum durum, T. aestivum and T. dicoccon for subsequent morphological characterization and investigations on stress adaptation. The results show that the cultivation of these landraces (the genetic composition of which remains to be studied in more detail) is done primarily by traditional farmers who preserve the inherited germplasm on often tiny plots in remote mountain oases. This type of traditional cultivation is under heavy economic pressure. An appendix of landraces of other crops collected in the Batinah region and in the mountain oases can be found online.

Die Wirkungen von Extensivierungs- und Vertragsnaturschutzprogrammen auf die Entwicklung einer "gerade noch aktuellen Agrarlandschaft"

Erfolgskontrollen für Agrarumweltprogramme bezogen sich bisher meistens auf einzelne Flächen oder auf programmbezogene, großräumige Evaluationen. Es wurde jedoch kaum untersucht, wie sich die Maßnahmen auf die Entwicklung einzelner Naturräume auswirken. Auch gab es keine Studien, welche die Wechselwirkungen zwischen den Beweggründen der Landnutzer auf der ei-nen- sowie Landnutzung und Vegetation auf der anderen Seite interpretierten. Die Dissertation Wirkungen von Extensivierungs- und Vertragsnaturschutzprogrammen auf die Entwick-lung einer »gerade noch aktuellen Agrarlandschaft« hat diese Lücke geschlossen. Sie erklärt, welche Bedeutung die hessischen Programme HELP und HEKUL für den hohen Anteil naturschutzfachlich wertvollen Grünlands im Rommeroder Hügel-land westlich des Meißner haben. Untersuchungsgegenstand waren die Grünlandvegetation und die landwirtschaftlichen Betriebe mit ihren Menschen und deren Beweggründen. Diese Inhalte er-forderten eine Vorgehensweise, die sowohl sozialwissenschaftliche als auch naturwissenschaftliche Methoden einbindet, um Bezüge zwischen Betrieben und Grünlandvegetation zu er-kennen. Umfangreiche pflanzensoziologische Untersuchungen und Interviews der Betriebsleiter waren Grundlage für eine Schlagdatenbank und weitergehende Auswertungen. Die Interpretation vegetationskundlicher Erhebungen im Kontext betrieblicher Entscheidungen und Beweggründe erforderte es, althergebrachte Ansätze in neuer Form zu verknüpfen. Die Bewertung der Programmwirkungen stützte sich auf die Schlagdatenbank und auf vier Szena-rien zur zukünftigen Gebietsentwicklung bei unterschiedlichen Programmfortschreibungen. Zur Darstellung von Erhebungen und Ergebnissen entstand eine Vielzahl thematischer Karten. Der überdurchschnittlich hohe Anteil naturschutzfachlich bedeutsamer Grünlandtypen auf den Programmflächen und die Interpretation der Szenarien belegten eine hohe Wirksamkeit von HELP und HEKUL im Gebiet. Nicht nur auf den Vertragsnaturschutzflächen des HELP, sondern auch auf dem HEKUL-Grünland sind naturschutzfachlich bedeutende Vegetationstypen überproportional vertreten. Die vier Szenarien ließen erkennen, dass eine Beschränkung des HELP auf Schutzgebiete, eine Abschaffung der HEKUL-Grünlandextensivierung oder gar eine ersatzlose Strei-chung beider Programme zu erheblichen Verschlechterungen der naturschutzfachlichen Situation führen würde. Gleichzeitig war festzustellen, dass es ohne die landwirtschaftlich schwierigen natur-räumlichen Verhältnisse sowie eine eher großteilige Agrarstruktur mit überdurchschnittlich flächen-starken und wirtschaftlich stabilen Vollerwerbsbetrieben keine so deutlichen Programmwirkungen gegeben hätte. Auch die Tatsache, dass viele Landwirte eine intensive Landwirtschaft aus innerer Überzeugung ablehnen und mit einer erheblich geringeren Stickstoffintensität wirtschaften als es HEKUL verlangt, wirkte verstärkend. Die große Bedeutung individueller Beweggründe einzelner Betriebsleiter wurde auch in den engen Beziehungen einzelner Grünland-Pflanzengesellschaften zu bestimmten Betriebstypen und sogar einzelnen Höfen sichtbar, deren Beschreibung und Interpretation wichtige Erkenntnisse zu den so-zioökonomischen Voraussetzungen verschiedener Vegetationstypen lieferte. Für die zukünftige Entwicklung der hessischen Agrarumweltförderung empfiehlt die Dissertation eine Einführung und bevorzugte Anwendung ergebnisorientierter Honorierungsverfahren, eine bessere Berücksichtigung des gering gedüngten Grünlands über eine differenzierte Förderung sehr extensiver Düngeregime, eine stärkere Modularisierung des Gesamtprogramms und eine Durchführung aller Maßnahmen im Vertragsverfahren. Die betriebszweigbezogene Grünlandextensivierung sollte zukünftig in Kulissen angeboten werden, in denen ein verstärktes Wechseln von Betrieben in die Mindestpflege nach DirektZahlVerpflV zu erwarten ist.

Design, implementation and application of a generic framework for integrated regional land-use modeling

Land use is a crucial link between human activities and the natural environment and one of the main driving forces of global environmental change. Large parts of the terrestrial land surface are used for agriculture, forestry, settlements and infrastructure. Given the importance of land use, it is essential to understand the multitude of influential factors and resulting land use patterns. An essential methodology to study and quantify such interactions is provided by the adoption of land-use models. By the application of land-use models, it is possible to analyze the complex structure of linkages and feedbacks and to also determine the relevance of driving forces. Modeling land use and land use changes has a long-term tradition. In particular on the regional scale, a variety of models for different regions and research questions has been created. Modeling capabilities grow with steady advances in computer technology, which on the one hand are driven by increasing computing power on the other hand by new methods in software development, e.g. object- and component-oriented architectures. In this thesis, SITE (Simulation of Terrestrial Environments), a novel framework for integrated regional sland-use modeling, will be introduced and discussed. Particular features of SITE are the notably extended capability to integrate models and the strict separation of application and implementation. These features enable efficient development, test and usage of integrated land-use models. On its system side, SITE provides generic data structures (grid, grid cells, attributes etc.) and takes over the responsibility for their administration. By means of a scripting language (Python) that has been extended by language features specific for land-use modeling, these data structures can be utilized and manipulated by modeling applications. The scripting language interpreter is embedded in SITE. The integration of sub models can be achieved via the scripting language or by usage of a generic interface provided by SITE. Furthermore, functionalities important for land-use modeling like model calibration, model tests and analysis support of simulation results have been integrated into the generic framework. During the implementation of SITE, specific emphasis was laid on expandability, maintainability and usability. Along with the modeling framework a land use model for the analysis of the stability of tropical rainforest margins was developed in the context of the collaborative research project STORMA (SFB 552). In a research area in Central Sulawesi, Indonesia, socio-environmental impacts of land-use changes were examined. SITE was used to simulate land-use dynamics in the historical period of 1981 to 2002. Analogous to that, a scenario that did not consider migration in the population dynamics, was analyzed. For the calculation of crop yields and trace gas emissions, the DAYCENT agro-ecosystem model was integrated. In this case study, it could be shown that land-use changes in the Indonesian research area could mainly be characterized by the expansion of agricultural areas at the expense of natural forest. For this reason, the situation had to be interpreted as unsustainable even though increased agricultural use implied economic improvements and higher farmers' incomes. Due to the importance of model calibration, it was explicitly addressed in the SITE architecture through the introduction of a specific component. The calibration functionality can be used by all SITE applications and enables largely automated model calibration. Calibration in SITE is understood as a process that finds an optimal or at least adequate solution for a set of arbitrarily selectable model parameters with respect to an objective function. In SITE, an objective function typically is a map comparison algorithm capable of comparing a simulation result to a reference map. Several map optimization and map comparison methodologies are available and can be combined. The STORMA land-use model was calibrated using a genetic algorithm for optimization and the figure of merit map comparison measure as objective function. The time period for the calibration ranged from 1981 to 2002. For this period, respective reference land-use maps were compiled. It could be shown, that an efficient automated model calibration with SITE is possible. Nevertheless, the selection of the calibration parameters required detailed knowledge about the underlying land-use model and cannot be automated. In another case study decreases in crop yields and resulting losses in income from coffee cultivation were analyzed and quantified under the assumption of four different deforestation scenarios. For this task, an empirical model, describing the dependence of bee pollination and resulting coffee fruit set from the distance to the closest natural forest, was integrated. Land-use simulations showed, that depending on the magnitude and location of ongoing forest conversion, pollination services are expected to decline continuously. This results in a reduction of coffee yields of up to 18% and a loss of net revenues per hectare of up to 14%. However, the study also showed that ecological and economic values can be preserved if patches of natural vegetation are conservated in the agricultural landscape. -----------------------------------------------------------------------