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The human vaginal microbiota plays essential roles in preventing pathogenic bacteria, fungi, and viruses from invading. The dominant vaginal Lactobacillus species show great potential to be developed as probiotics.

Drip irrigation systems are becoming more and more mature and are now widely used to improve crop yield and nitrogen use efficiency in Xinjiang, NW China. However, it is not known if leaching is occurring or not and whether leaching will harm the water environment following N fertilization and drip irrigation. The purpose of our study was to estimate the leaching volumes, nitrogen losses, forms of nitrogen losses, and nitrogen loss coefficients under different N fertilization, P fertilization, K fertilization and irrigation regimes. A long-term field experiment was conducted from 2009 to 2015 in Baotou Lake farm in Korla City, Xinjiang, with drip-irrigated cotton (Gossypium hirsutum L.) being grown under different N fertilizer and irrigation regimes. The treatments were designed comprising 0 N, 0 P, and 0 K with an irrigation of 480 mm as the control(N0P0K0W480) and the following three other treatments: (1) 357 kg N&middot, hm&minus, 2, 90 kg P&middot, 2, 0 kg K2O hm&minus, 2, and irrigation of 480 mm (N357P90K0W480), (2) 357 kg N&middot, 2, 62 kg K&middot, 2, and irrigation of 420 mm (N357P90K62W420), and (3) 240 kg N&middot, 2, 65 kg P&middot, 2, and irrigation of 420 mm (N240P65K62W420). The results showed the following: (1) the leaching volume was determined by nitrogen fertilization, phosphorus fertilization, and the irrigation amount. In general, the leaching volume was highest under treatment N357P90K0W480. (2) The nitrogen loss was highest under treatment N357P90K0W480. (3) Nitrate nitrogen (NO3&ndash, ) was the main form of nitrogen lost, followed by ammonium nitrogen (NH4+). (4) The annual nitrogen loss coefficients followed the order of: N357P90K0W480 &gt, N357P90K62W420 &gt, N240P65K62W420 &gt, N0P0K0W480, with values of 0.85, 0.55, 0.30, and 0, respectively. The leaching volume, nitrogen loss, nitrate nitrogen, ammonium nitrogen, and annual nitrogen loss coefficient were lowest under the N240P65K62W420 treatment, except in the N0P0K0W480treatment. These results demonstrate that optimizing the management of water and nitrogen (N240P65K62W420 treatment) can effectively reduce nitrogen losses under drip fertigation and plastic mulching.

Drip irrigation under plastic mulch is widely used in Xinjiang, Northwest China. It can not only save water, but also reduce nutrient loss and improve fertilizer utilization. However, it is not clear whether the leaching occurs or not, what is the leaching amount? What is the relationship among fertilization, irrigation regimes, loss, cotton absorption, and cotton field under different fertilization and irrigation management under drip irrigation? Studying these issues not only provides reference for the formulation of fertilization and irrigation systems, but also is of great significance for reducing non-point source pollution. A long-term positioning experiment was conducted from 2009 to 2012 in Baotou Lake farm in Korla City, Xinjiang, with drip-irrigated cotton (Gossypium hirsutum L.) under different N fertilizer and irrigation amounts. The treatments were designed comprising Control (CK,0 N, 0 P, and 0 K with an irrigation of 480 mm) and the following three other treatments: (1) Conventional fertilize and irrigation (CON, 357 kg N hm–2, 90 kg P hm–2, 0 kg K hm–2, and irrigation of 480 mm); (2) Conventional fertilization and Optimizing irrigation (OPT, 357 kg N hm–2, 90 kg P hm–2, 62 kg K hm–2, and irrigation of 420 mm); and (3) Optimizing fertilization and irrigation (OPTN, 240 kg N hm–2, 65 kg P hm–2, 62 kg K hm–2, and irrigation of 420 mm). The results found that the leaching would occur in arid area under drip irrigation. The loss of total N, NH4+, P, N and P loss coefficient was higher under conventional fertilize and irrigation treatment while the loss of NO3- was higher under conventional fertilization and optimizing irrigation treatment. The correlations among N, P absorption by cotton, loss of NH4+ and total phosphorus were quadratic function. The total nitrogen loss and cumulative nitrogen application was lineally correlated. The loss of NO3- and cumulative nitrogen application was exponential. The nitrogen and phosphorus absorption by cotton under conventional fertilization and optimizing irrigation treatment was 24.53% and 35.86% higher than that in conventional fertilize and irrigation treatment, respectively. The cotton yield under conventional fertilization and optimizing irrigation treatment obtained higher than that in other three treatments. Therefore, the conventional fertilization and optimizing irrigation treatment was the optimal management of water and fertilizer in our study. These results demonstrate that reasonable water, nitrogen and phosphorus fertilize could not only effectively promote the absorption of nitrogen and phosphorus, but also reduce nitrogen and phosphorus losses under drip fertigation and plastic mulching.

A model for Olsen-P (extracted by 0.5 mol L−1 NaHCO3 at pH 8.5) accumulation in soils, established using several experimental field sites, has not been validated by a large scale dataset. In the present study, a long-term (maximally 24 years), large-scale, regional soil monitoring dataset consisting of 58 sites from four provinces (Hebei, Henan, Shandong and Shanxi) of the main wheat (Triticum aestivum L.)–maize (Zea mays L.) rotation production areas in China was used to validate the developed model for Olsen-P accumulation in soils for both inorganic and organic P fertilization. The results showed that with fertilizer P application rates of 56.3–103 kg P ha−1, total wheat–maize yields between 12.3 and 13.1 t ha−1 were obtained with net gains of 21.7–77.9 kg P ha−1 yr−1in the soils in these areas. The accumulation of Olsen-P in the P-fertilized soils above the initial soil Olsen-P contents could be predicted by fertilizer P application rates (including organic and inorganic P sources), crop yields and soil pH. According to the model, the mean accumulation rate of Olsen-P in the main wheat–maize rotation areas of China was 1.29 mg kg−1 yr−1, which was close to the measured mean value of 1.14 mg kg−1 y−1. The soil Olsen-P accumulation model could provide a valuable predictive tool, decreasing the frequency of Olsen-P monitoring in soils and improving soil phosphorus management for both agricultural production and environmental protection.

In many areas, such as plains and gently undulating terrain, easy-to-measure soil-forming factors such as landform and vegetation do not co-vary with soil conditions across space to the level that they can be effectively used in digital soil mapping. A challenging problem is how to develop a new environmental variable that co-varies with soil spatial variation under these situations. This study examined the idea that change patterns (dynamic feedback patterns) of the land surface, such as those captured daily by remote sensing images during a short period (6-7 d) after a major rain event, can be used to differentiate soil types. To examine this idea, we selected two study areas with different climates: one in northeastern China and the other in northwestern China. Images from the Moderate Resolution Imaging Spectroradiometer (MODIS) were used to capture land surface feedback. To measure feedback dynamics, we used spectral information divergence (SID). Results of an independent-samples t-test showed that there was a significant difference in SID values between pixel pairs of the same soil subgroup and those of different subgroups. This indicated that areas with different soil types (subgroup level) exhibited significantly different dynamic feedback patterns, and areas within the same soil type have similar dynamic feedback patterns. It was also found that the more similar the soil types, the more similar the feedback patterns. These findings could lead to the development of a new environmental covariate that could be used to improve the accuracy of soil snapping in low-relief areas.

The evolution toward the standardized market design (SMD) is presented in this paper with references to the market developments in New Zealand, Australia, PJM, ISO-NE, and ERCOT. In the development of market designs, two main objectives-market liquidity facilitating bilateral trading and pricing efficiency facilitating congestion management, have been pursued. The efforts to balance the seemingly conflicting objectives led to most markets designed with a uniform or zonal pricing model. Introduction of locational marginal pricing and evolution of transmission rights from physical to financial form made it possible to harmonize the potentially conflicting goals in a market design. The close coupling between energy and ancillary services requires that markets for these commodities be carefully coordinated. Different operational practices and reliability standard requirements have led to major differences in ancillary service market designs.

Competitive bidding for ancillary services (A/S), in addition to bidding for energy, is increasingly recognized as an important part of electricity markets. In this paper, an LP-based approach is presented for solving the multi-product (i.e. energy and A/S products), multi-zone/area physical market dispatch problem. The approach can explicitly represent various constraints, such as reserve requirement constraints, network security limits, and sharing of constrained resource capacity (e.g. maximum unit generation) between energy and reserve. The joint dispatch method, which dispatches energy and reserve market concurrently, is extended to allow inter-zonal reserve trading in a multi-zone competitive pool. Numerical examples are included to demonstrate the salient characteristics of the joint dispatch solution.

This paper reports upon the mathematical models and implementation of the Scheduling, Pricing and Dispatch (SPD) application for the New Zealand Electricity Market (NZEM). SPD analyzes bids for energy offers, reserve offers and energy demands, and recognizes explicitly the effects on bid clearing due to transmission congestion, network losses, reserve requirements, and ramp rate limits. Advanced LP solution methods are utilized to solve the large-scale constrained optimization problem. Results on a 67-bus test system and the NZEM are included.

The purpose of this paper is to analyze various approaches to incorporate short-term stored energy resources into the Midwest ISO co-optimized energy and ancillary service market. Based on the analysis, the best approach is to utilize short-term stored energy resources for regulating reserve with the real-time energy dispatch to be set in such a way that the maximum regulating reserve can be cleared. Results on a five-bus system are used to illustrate the clearing and pricing on short-term stored energy resources with the proposed approach. Monte Carlo simulation on the five-bus system is used to illustrate the AGC regulation deployment.

The purpose of this paper is to describe various methods fo r ut ilizing ramp capability in the Midwest ISO co-optimized real time energy and ancillary service market design. A critical component of successful market design is to improve market economic efficiency as well as grid reliability. The paper co mpares studies on various proposed ramp models. Examples on both 5-bus and Midwest ISO system are used to demonstrate their impacts on dispatch results and pricing.

This paper reports upon the security-constrained commitment and dispatch algorithms and their implementation for Midwest ISO's day-ahead co-optimized energy and ancillary service markets. The MIP method is utilized to solve the DA market and the RA commitment problems and the LP method solves the DA market clearing problem. Demand response resources are qualified for provision of energy and ancillary services. AS demand curves are introduced to allow for efficient pricing of energy and AS capacities by location. Efficient price signals are expected to induce new generation additions, demand response participations and thus improve grid reliability.

Electricity restructuring is centered on economic efficiency as well as grid reliability for both short and long terms. Successful markets are characterized with the common key elements. The key market elements include: locational marginal pricing (LMP), financial transmission right (FTR) and co- optimized energy and ancillary service market. As critical components of a successful market design, risk hedging mechanisms are presented including multi-settlement scheme, virtual bidding and bilateral contracts. Market mechanisms for long-term transmission and generation capacity adequacy are under development in the US several US markets and will be discussed in the paper. Examples are used to demonstrate the workings of the key market elements.

Competitive bidding in a pool electricity market is likely to extend beyond energy to include ancillary services. The purpose of this paper is to identify and analyze alternative methods for dispatching ancillary services in a pool-oriented electricity market.

This paper discusses the functional design of the new ancillary service markets (ASM) of ISO New England under the framework of standard market design (SMD). The re-introduction of ancillary service markets into ISO New England's wholesale electricity market is envisioned to correctly value and price the actions necessary to prepare for and maintain the reliability of power system dispatch in conjunction with operating an efficient energy market. The new ASM consists of a forward reserve market, a real-time reserve market and a redesigned regulation market energy and various ancillary services are simultaneously cleared and locational energy and reserve prices are produced in real-time. The relationship between the regulation clearing and the co-optimization of energy and reserves is discussed..

Key elements of a successful market design are discussed in this paper with reference to several US markets in Mid-Atlantic (PJM), New England (ISO-NE) and Midwest (MISO) regions. The key market elements discussed include: locational marginal pricing (LMP), financial transmission right (FTR) and co-optimized energy and ancillary service market. As critical components of a successful market design, risk hedging mechanisms are presented including multi-settlement scheme, virtual bidding and bilateral contracts. A capacity market construct is presented that is under development in the US and is intended to provide price signals for long-term generation and transmission investments. Examples are used to demonstrate the workings of the key market elements

This paper introduces the fundamental features of the financial transmission rights (FTR) auction market and the implementation of the market clearing system in PJM. With the FTR auction market, PJM electricity market participants can more readily buy or sell FTRs to hedge their financial exposure to price risks caused by transmission congestion which is inherent to the LMP based market mechanism. The FTR Auction market bid-clearing system follows a rigorous optimization-based framework and has the capability to handle various types of sophisticated security constraints, such as reactive transfer limits and contingency constraints. Numerical examples, including the one using the PJM network model, are included to demonstrate the various aspects of the FTR auction mechanism.