盐的眷恋

海水盘成盐,在透明中运作,在透明中成长。也练就了盐场人豪爽透明的性格。盐场人的情,柔肠百转,真诚如晶。男人顶天立地,大苦不说。女人热爱生活,大爱不言。浩瀚的大海,孕育着千万种生灵,奉献着数不尽的宝藏。盐,这一伴随人类走来的宝藏,源自大海,由水而成,一路吃尽     

追野兔

那时,家后的河堤上,海边的沙滩草丛中,野兔几乎赶上耗子多。只要人到草丛里,就能有野兔出没。于是,大家就经常玩起逮野兔的游戏。海浪,沙滩,湿地,海堤,大河,养水滩,多样性的地貌小环境,使老家海堤内外的滩地,成为动物和候鸟们经常光顾的圣地佳境。天鹅、野鸭、海鸥、鹤鹤,还有各种水鸟,一年四季轮番落脚,给那片水域带来了勃勃生机。有时候,它们在一个水域的水里岸上,就像开运动会似的,展示自己的才华。天鹅优雅的身姿,翩翩起舞的样子,在所有水禽里显得无上高贵。小溜根     

故乡的四口塘

正故乡的四口塘,伴随了我整个的童年,带给我无数的欢乐,也留给我难忘的记忆。不久前,一个散淡的日子,我回到故乡,走访了这四口塘。这四口养育我及村人的塘,荒凉,潦倒,病入膏肓。我站立塘埂,感叹、悲伤,我希望它能逃脱死亡的命运,重新造福故乡人民。长塘长塘,故乡的一口长方形的塘。长塘埂种有乡村最廉价的杨树,树身粗糙,树顶撑起来如一把伞。     

可爱的“海猫”

是啊,人这良心可不能坏。坏到逮光了鱼杀光了鸟,这样的海,只能叫死海。我们不希望在我们身边潮起潮落千年万年的大海变成死海。海堤连着湿地,湿地连着沙滩,沙滩牵手海滩。在这片范围不是很大的潮上带海边,长年生活着一种叫海猫的海鸟。它或漂流于起伏不定的海浪之中,或静静地站立在沙滩之上,或摇摆着身子漫不经心的散步。它一年四季从不离去,也从未有人去打扰。它在海边生活了多少年,也只有它们自己知道。海猫,是我们叫的土话,学名叫海鸥。有海的地     

生态城市建设畅想曲——评《森林都市EGEC》

<正>森林是万物的摇篮。与地球共生,新世纪的都市建设已然开始。"森林,是多种生命的集合体。既养育生命,也独自增殖。我们的祖先,也曾以此为家。获得文明的人类,虽已开拓森林、构筑城市,但森林摇篮的记忆,通过DNA而得以传递。与森林共生并非理性,而是生命的真谛。故,森林是永远的眷恋。""都市,是人类生活的空间。换而言之,是生活活动的森林。伦敦、纽约以及东京等城市,是世界上拥依广袤森林而发展起来的     

山沟记忆:山野之味

秦岭的南麓。崇山峻岭中,我度过自己的童年、少年时光。山里藏着多少宝物啊。最著名的,应该算猕猴桃了。据说,大闹天宫的孙行者及其徒子徒孙最爱吃,因此得名。山里的猕猴桃,不似后来在城里见到的那么大,那么硬。我记得,似乎个头要小些,绿豆青的果子上,长满了长长的毛。如果在果子表面,画上鼻子眼睛,直接说是猴子脸,包准没人不信。这果子的好处,是后来听说的,类似神仙果,维生素大V,比苹果维生素含量丰富多了——当时在沟里,倒也不觉得多稀奇,似乎也不容易碰到猕猴桃树。而核桃树,则是满山都有的,应该不是老乡特意种的。核桃树长在远离住家的地方,也许,是哪一只小鸟衔的种子,偶尔掉落地上,就此在山林间扎下根来,自生自长。常常,能看到圆圆的刺猬一样的青核桃掉     

新年,我们为环保许愿

许愿,只是一种仪式。而在新年,对将来的环保许愿,这就不是一种简单的仪式,而是发自内心的愿望。这种愿望能使许愿的人身体力行,参与环保。只有对环保许愿的人多了,美丽中国才值得期待。每到年头岁尾,人们都喜欢在总结一年得失的时候,给自己许个愿。许愿的场景各有不同,而最正统的许愿方式,一般都是到寺庙里,烧一炷香,磕几个头,然后爬起来,双手合十,闭上双眼,将自己的     

还你一片蓝天——写给孙女玛丽娅的一封信

正亲爱的孙女玛丽娅:你好!马年年初开始的雾霾,在那些时日让你咳嗽、发烧,看着你受煎熬我心里很难过。虽然我们买来空气净化器,屋里的空气相对清洁些,或者说,应当达标。但是,一眼望出去,连对面的楼都灰蒙蒙的看不太清楚,让人伤神。你的清澈的视线,被阴暗的雾霾遮蔽着,我只能用我心灵的阳光来为你扫清雾霾。的确,北京的天空,曾经很蓝很蓝。但是,近两年来,北京屡屡遭遇雾霾。这是因为我们一度只顾了经济发展,倚重GDP指标。于是,顾     

合肥“大水缸”困局

水安则邦安,水兴则邦兴。亘古至今,这是人类社会公认的法则。然而,一个不容回避的事实是,当今城市在高速发展的同时,饮用水安全问题已日益成为制约城市发展的瓶颈。合肥,安徽省省会,一座正在飞速崛起的城市。历史因水多,故合肥又称合淝。然而,时过境迁,如今,合肥也饱受饮用水安全之困。管中窥豹,日前,本刊记者前往合肥大水缸实地探访,以从中窥视出当今城市所面临的饮用水安全问题。     

爱是一个圆

应邀去参观女友的新居。进得门来,朋友两岁的小女乐颠颠地递来拖鞋。她粉嘟嘟的模样,如一朵娇俏的花骨朵。欣喜地牵着小女,在各个房间里转悠。女友和她的爱人,都是中学老师。受此熏染,这居所的格调也简洁雅致,颇有书香气息。装     

Efficacy of alum and coal combustion by-products in stabilizing manure phosphorus

Animal manures contain large amounts of soluble phosphorus (P), which is prone to runoff losses when manure is surface-applied. Here we report the efficacy of alum and three coal combustion by-products in reducing P solubility when added to dairy, swine, or broiler litter manures in a laboratory incubation study. Compared with unamended controls, alum effectively reduced readily soluble P, determined in water extracts of moist manure samples with 1 h of shaking, for all three manures. The reduction ranged from 80 to 99% at treatment rates of 100 to 250 g alum kg(-1) manure dry matter. The fluidized bed combustion fly ash (FBC) reduced readily soluble P by 50 to 60% at a rate of 400 g kg(-1) for all three manures. Flue gas desulfurization by-product (FGD) reduced readily soluble P by nearly 80% when added to swine manure and broiler litter at 150 and 250 g kg(-1). Another by-product, anthracite refuse fly ash (ANT), was ineffective for all three manures. In all cases, reduction in readily soluble P is primarily associated with inorganic phosphorus (P(i)) with little change in organic phosphorus (P(o)). Sequential extraction results indicate that the by-product treatments shifted manure P from H2O-P into a less vulnerable fraction, NaHCO3 - P, while the alum treatment shifted the P into even more stable forms, mostly NaOH-P. Such shifts in P fractions would have little influence on P availability for crops over the long-term but would retard and reduce potential losses of P following manure applications.     

TEMPORAL VARIATION IN THE NUTRIENT EXPORT OF RIVERS DRAINING INTO THE BAY OF QUINTE,ONTARIO, CANADA1

ABSTRACT: Annual exports of total phosphorus, soluble reactive phosphorus, and total nitrogen are presented for the period 1965–1974, for five rivers draining into the Bay of Quinte, Lake Ontario. The export values are typical for the physiography and land use though the results indicate that soluble reactive phosphorus exports for the four largest rivers have been declining. Also the variation in export of total phosphorus and total nitrogen is highly correlated with variation in annual runoff. This is noted as being a factor deserving more attention in future efforts to classify nutrient export values in relation to land use and geology.     

湖泊沉积物中磷的形态分析及其释放研究

本文讨论了湖泊沉积物中磷的各种存在形态，包括：可交换性溶解磷（Pa-t），可溶性磷（Psol），经结合态磷（Pu），铁结合态磷（PFc），以及闭态磷（O-P），另外，还有部份有机磷（Porg），利用分级提取技术，□□□□□□氧）对湖水复磷影响显著，主要是释放PAf和PFc。     

Climatic and agricultural contributions to changing loads in two watersheds in Ohio

Trends in climatic variables, streamflow, agricultural practices, and loads of nutrients and suspended solids were estimated for 1976-1995 in the Maumee and Sandusky watersheds, two large agricultural basins draining to Lake Erie. To understand the contributions that various factors may have made to the trends in loads, earlier results of models linking loads to explanatory variables were combined with estimated trends in those variables. The study period was characterized by increases in temperature, wintertime precipitation and streamflow, conservation farming, and loads of nitrate and total suspended solids; decreases in snowfall and snow cover, fertilizer, manure from livestock, and loads of soluble reactive phosphorus; and relatively steady exports of total phosphorus. After removing the effects of trends in streamflow, nitrate loads increased much less while total suspended solids and total phosphorus loads declined. The analysis suggests that the nitrate increases were due largely to climatic factors, particularly increases in winter streamflow, decreases in snowfall and snow cover, and declining annual precipitation. Decreases in soluble reactive phosphorus were associated with changes in agricultural practices, particularly declines in fertilizer deliveries and head of livestock.     

Microcosm studies on anaerobic phosphate flux and mineralization of lake sediment organic carbon

Lake sediment has long been recognized as an important source of nutrients such as phosphorus. To gain a better understanding of phosphorus flux at the sediment-water interface, it is crucial to investigate the sediment porewater. There is also growing concern and interest in identifying whether organic-rich sediment is an important source of greenhouse gases such as CO(2) and CH(4). In the present study, we took sediment samples from West Lake, a shallow hypereutrophic lake in Hangzhou, Zhejiang Province, China and incubated subsamples under anaerobic conditions at 25 degrees C for 182 d using a specially designed microcosm that permits repeated extraction of sediment porewater and sampling of headspace gases. Anaerobic phosphate fluxes and mineralization of sediment organic carbon were measured. Average diffusive flux of soluble phosphorus was 0.81 mg P m(-2) d(-1) during the initial 18 d of incubation. Decomposition of sediment organic C followed zero-order reaction kinetics and methane accounted for about 50% of the mineralization products. The results suggest that organic-rich sediments can be important sources of P and methane under anaerobic conditions. Laboratory studies simulating field conditions and field studies are necessary to determine the contribution of sediment as a source of P and greenhouse gases.     

The Influence of Two‐Stage Ditches with Constructed Floodplains on Water Column Nutrients and Sediments in Agricultural Streams

The two‐stage ditch is a novel management practice originally implemented to increase bank stability through floodplain restoration in channelized agricultural streams. To determine the effects of two‐stage construction on sediment and nutrient loads, we monitored turbidity, and also measured total suspended solids (TSS), dissolved inorganic nitrogen (N) species, and phosphorus (P) after two‐stage ditch construction in reference and manipulated reaches of four streams. Turbidity decreased during floodplain inundation at all sites, but TSS and P, soluble reactive phosphorus (SRP) and total phosphorus (TP) decreased only in the two‐stage ditches with longer duration of inundation. Both TSS and TP were positively correlated within individual streams, but neither were correlated with turbidity. Phosphorus was elevated in the stream to which manure was applied adjacent to the two‐stage reach, but not the reference reach, suggesting that landscape nutrient management plans could restrict nutrient transport to the stream, ultimately determining the efficacy of instream management practices. In addition, ammonium and nitrate decreased in two‐stage reaches with lower initial N concentrations. Overall, results suggest that turbidity, TSS, and TP were reduced during floodplain inundation, but the two‐stage alone may not be effective for managing high inorganic N loads.     

WATER QUALITY TRENDS IN LAKE TOHOPEKALIGA,FLORIDA, USA: RESPONSES TO WATERSHED MANAGEMENT1

ABSTRACT: Water quality in eutrophic Lake Tohopekaliga, Florida, improved markedly from 1982 to 1992 as a result of reductions in phosphorus and nitrogen loading to the lake. Annual budgets of water, chloride, phosphorus and nitrogen were constructed for the lake, and indicate it is a sink for phosphorus and a source for nitrogen. Water column concentrations of total phosphorus, soluble reactive phosphorus, total nitrogen, dissolved inorganic nitrogen, and chlorophyll a all declined as external inputs of nutrients decreased. Water column nitrogen: phosphorus ratios have increased, suggesting a probable shift from nitrogen- to phosphorus-limitation. This apparent shift in nutrient limitation status also is supported by comparisons of the mean Trophic State Indices for phosphorus, nitrogen, and chlorophyll a. These improvements in water quality are attributed to the diversion of wastewater treatment plant effluent from the lake, and the increased use of wet retention ponds for stormwater runoff.     

Relationships among plant available phosphorus, fertilizer sales, and water quality in northwestern Ohio

Soluble reactive phosphorus (SRP) in northwestern Ohio river water has declined over the past 20 yr in response to decreased applications of fertilizer P. Our objective was to evaluate changes in soluble P (Bray-1 P) levels in the soil over time as influenced by fertilizer P management, cultivation practice, soil properties, and landscape factors. Because soil is the intermediary between added P and SRP measured in river water, we examined the relationship between fertilizer P, soluble soil P, and SRP. Using historical soil survey sample sites as a baseline for original soluble P concentrations (Por), we resampled Ap horizons to establish current levels of soluble P (Pcu). The Por baseline extended from 1953-1982 and Pcu from 1996-1998. Thirty percent of the Pcu values and 17% of the Por values were > or = 40 mg kg(-1). Log-transformed means for Pcu were significantly higher than for Por. The principal determining factors for Por were physiography, soil texture, and soil series. Current P is affected by present tillage practice and drainage class. Change in soluble P in the soil is not as responsive to fertilizer P sales as is SRP in river water. This suggests that as fertilizer P sales decline, a declining percentage of P added as fertilizer is annually dissolved and transported into the drainage system. Soluble P in soil is governed by a combination of fertilizer and tillage management, soil properties, and landscape factors interacting over time.     

Phosphorus characteristics of dairy feces affected by diets

Phosphorus (P) surplus on dairy farms, especially confined operations, contributes to P buildup in soils with increased potential for P loss to waters. One approach to reduce P surplus and improve water quality is to optimize P feeding and improve P balance on farms. Here we report how varying P concentrations in lactating cow diets affects the amount as well as the chemical forms and fraction distribution of P in fecal excretion, and the environmental implications of this effect. Analysis of fecal samples collected from three independent feeding trials indicates that increasing dietary P levels through the use of P minerals not only led to a higher concentration of acid digest total phosphorus (TP) in feces, but more importantly increased the amount and proportion of P that is water soluble and thus most susceptible to loss in the environment. For instance, with diets containing 3.4, 5.1, or 6.7 g P kg(-1) feed dry matter (DM), the water-soluble fraction of fecal P was 2.91, 7.13, and 10.46 g kg(-1) fecal DM, respectively, accounting for 56, 77, and 83% of acid digest TP. The other fecal P fractions (those soluble in dilute alkaline and acid extractants) remained small and were unaffected by dietary P concentration. Excess P in the P supplemented diets was excreted in feces as water-soluble forms. A simple measure of inorganic phosphorus (Pi) in a single water extract is highly responsive to changes in diet P concentrations and hence can be indicative of dietary P status. A fecal P indicator concept is proposed and discussed.     

PHOSPHATE IN WATERS: I. REDUCTION USING NORTHERN LIGNITE FLY ASH1

Fly ashes fiom lignite coal fixed steam electric plants contain appreciable amounts of materials that can, in principle, decrease the phosphorus concentration in surface waters. Typical samples of un-weathered fly ash were used to test efficacies of removal of phosphorus from standard phosphate solutions and actual lake water samples. The effects of changing parameters such as contact time, pH, fly ash/water ratios, and solution temperature are presented. Water soluble and insoluble factors in the ash both appear to be reactive constituents. Trials with municipal waste waters showed near quantitative removal of ortho-phosphate.