Phosphorus Leaching Under Cut Grassland

1999 ◽  
Vol 39 (12) ◽  
pp. 63-67 ◽  
Author(s):  
B. L. Turner ◽  
P. M. Haygarth
Keyword(s):  
Surface Waters ◽  
Large Scale ◽  
Agricultural Land ◽  
Algal Growth ◽  
Soil Types ◽  
P Fractions ◽  
Inorganic P ◽  
Potential Source ◽  
Significant Mechanism ◽  
Total P

Phosphorus (P) transfer from agricultural land to surface waters can contribute to eutrophication, excess algal growth and associated water quality problems. Grasslands have a high potential for P transfer, as they receive P inputs as mineral fertiliser and concentrates cycled through livestock manures. The transfer of P can occur through surface and subsurface pathways, although the capacity of most soils to fix inorganic P has meant that subsurface P transfer by leaching mechanisms has often been perceived as negligible. We investigated this using large-scale monolith lysimeters (135 cm deep, 80 cm diameter) to monitor leachate P under four grassland soil types. Leachate was collected during the 1997–98 drainage year and analysed for a range of P fractions. Mean concentrations of total P routinely exceeded 100 μg l−1 from all soil types and, therefore, exceeded P concentrations above which eutrophication and algal growth can occur. The majority of the leachate P was in algal-available Mo-reactive (inorganic) forms, although a large proportion occurred in unreactive (organic) forms. We suggest that subsurface transfer by leaching can represent a significant mechanism for agricultural P transfer from some soils and must be given greater consideration as a potential source of diffuse P pollution to surface waters.

scholarly journals Bottom sediments as a potential source of phosphorus in the riverine-lacustrine system of the Kośna River (Northeastern Poland)

2012 ◽  
Vol 12 (3) ◽  
pp. 115-124 ◽  
Author(s):  
Izabela Bigaj ◽  
Michał Łopata ◽  
Julita Dunalska ◽  
Daniel Szymański ◽  
Rafał Zieliński
Keyword(s):  
Rank Order ◽  
Inorganic Phosphorus ◽  
P Fractions ◽  
Iron Compounds ◽  
Inorganic P ◽  
Potential Source ◽  
Northeastern Poland ◽  
P Fraction ◽  
Labile P ◽  
P Budget

AbstractSediments from hypereutrophic Lake Łajskie localized in northeastern Poland were examined on the basis of P-fraction. The sediments were collected at five sampling sites. In the investigated lake, the rank order of P-fractions was HCl-P > BD-P > NH4Cl-P > NaOH - nrP. The loosely sorbed phosphorus NH4Cl-P represented < 3% of the sedimentary inorganic phosphorus, while the reductant phosphorus (BD-P) ranged from 2 to 10%. The calcium bound phosphorus (HCl-P) showed considerable contribution (59-74%) to the sedimentary inorganic P-loads. BDP was the most reactive fraction in Lake Łajskie. Iron compounds and organic matter seem to play a significant role in regulating this labile P-budget.

Changes in Environment and Biota of a Natural Lake after Fertilization

1969 ◽  
Vol 26 (12) ◽  
pp. 3101-3132 ◽  
Author(s):  
M. W. Smith
Keyword(s):  
Algal Blooms ◽  
Aquatic Vegetation ◽  
Algal Growth ◽  
Specific Conductance ◽  
Organic Production ◽  
Bottom Fauna ◽  
Rapid Loss ◽  
Inorganic P ◽  
Nitrate N ◽  
Total P

When artificial fertilizers were added to unstratified, soft-water Crecy Lake (20 ha), New Brunswick, in three years (1946, 1951, and 1959), the lake was sufficiently self-regulatory that the artificial enrichments had only a temporary effect on organic production. The induced eutrophication proved largely reversible, with minor evidence of hastened senescence of the lake over an 18-year period. Each fertilization provided 210 ppb (parts per billion) of nitrogen (N), 390 ppb of phosphorus (P), and 270 ppb of potassium (K) to the water if the fertilizers were equally distributed throughout the lake.The highest concentrations of total P, determined daily after the fertilizations in 1951 and 1959, were 220 ppb after 2 days and 192 ppb after 1 day, respectively. The concentration of inorganic P declined rapidly from about 150 ppb the day after the fertilizations in 1951 and 1959 to < 10 ppb at a percentage loss per day of 5.5. Concentrations of organic P were highest 5 (80 ppb, 1951) and 8 (43 ppb, 1959) days after the fertilizations and declined to equilibration above prefertilization values for 3–4 months, and then to prefertilization values during the next years. Phosphorus lost in the drainage from the lake, assessed only in 1951 and 1959, was equivalent in these years to 8.5 and 12% of the amounts added in the fertilizers.Limited observations indicated an increase of nitrate N in the water immediately after fertilization, but then a rapid loss. Deficits in dissolved oxygen were greatest under ice in the winters immediately after algal blooms induced by the fertilizers, but were serious in only about 30% of the volume of the lake. Specific conductance of the water exhibited minor change with fertilization.Pronounced algal blooms, not previously recorded for the lake, followed each fertilization. Years of fertilization, and the next, were marked by blooms of Anabaena. Intensified growth of Spirogyra usually followed closely the blooms of Anabaena. In the 3rd year after fertilization algal growth was weak, at prefertilization densities. During blooms of Anabaena the numbers of zooplankters and bottom organisms, and growth of submerged, rooted aquatic vegetation, decreased. Zooplankton and bottom fauna were most abundant 2–4 years after fertilizations. Of the rotifers, three out of eight species became abundant. Of the planktonic microcrustaceans, Leptodiaptomus was always the most numerous; Diaphanosoma and Daphnia were more numerous after the last fertilization (1959) than they were earlier. Among the bottom organisms, Hyalella, chironomids, Amnicola, and sphaeriids increased most in abundance after the fertilizations.

Changes in phosphorus fractions at various soil depths following long-term P fertiliser application on a Black Vertosol from south-eastern Queensland

Soil Research ◽  
2007 ◽  
Vol 45 (7) ◽  
pp. 524 ◽  
Author(s):  
X. Wang ◽  
D. W. Lester ◽  
C. N. Guppy ◽  
P. V. Lockwood ◽  
C. Tang
Keyword(s):  
Surface Soil ◽  
P Fractions ◽  
Inorganic P ◽  
Residual P ◽  
Soil P ◽  
P Pools ◽  
Fertiliser Application ◽  
P Addition ◽  
Total P

Long-term removal of grain P and soil test data suggested that the Colwell phosphorus (P) extraction from the surface 0.10 m of a Black Vertosol from south-eastern Queensland was a poor indicator of run-down of soil P pools. We proposed that plants were also accessing P from layers below 0.10 m or from surface soil P pools not extracted by the Colwell extraction. Both topsoil and subsoil samples in 1994 and 2003 were collected from nil and 20 kg P/ha per crop treatments in a long-term N × P field experiment established in 1985 for detailed P fractionation. An uncropped reference soil was also taken in 2003 from an adjacent area. The long-term effect of the field treatments on soil P fractions was evaluated by comparing the reference site, which was assumed to represent the original soil condition, to the 2003 samples. Without addition of P fertiliser, 55%, 35%, and 10% of total P removal were from 0 to 0.10, 0.10 to 0.30, and 0.30 to 0.60 m, respectively, compared with the uncropped reference soil. Labile fractions comprising resin, bicarbonate, and hydroxide pools in the top 0.10 m decreased by approximately 60% and accounted for 15% of the total P decrease from 0 to 0.60 m depth. Acid and residual-P fractions decreased by 50% and 20%, respectively, and accounted for ~20% and 15% of the total P decrease. In contrast, P addition at 20 kg P/ha per crop over 18 crops doubled the resin and bicarbonate inorganic P (NaHCO3-Pi) pools in the surface 0.10 m. Hydroxide (NaOH-Pi) and acid extracted inorganic P increased by 25% and 10%, respectively, while the residual-P pool decreased by about 15%. Below 0.10 m, very little P was removed by the first 3 extractants. Most of the P was present in the acid and residual fractions irrespective of fertiliser application. The acid and residual-P dropped by 30% and 12%, respectively, at 0.10–0.30 m and 12% and 8% at 0.30–0.60 m. When comparing the experimental soil samples in 2003 with those in 1994, similar trends were observed in the changes of each soil P fraction. In the surface 0.10 m, acid and residual-P pools decreased greatly and explained almost all of the total P decrease in the surface soil without P input. With P addition, labile pools acted as the main sink for P. The acid pool increased by 7%, while the residual-P showed a decrease in the topsoil. Total P level was elevated noticeably in this soil layer. However, at 0.10–0.30 m depth, acid and residual pools were the dominant fractions and decreased significantly irrespective of P fertiliser addition. Below 0.30 m, no significant changes were detected for each fraction and total P. The results suggest that crops had accessed significant amounts of P at 0.10–0.30 m depth irrespective of P fertiliser application, and that subsoil sampling (0.10–0.30 m) should be considered in order to improve the monitoring of soil P status. However, choice of appropriate extractants for monitoring subsoil P reserves is yet to be undertaken.

The partition of phosphorus and aneurin in relation to phosphatase in the colostrum and milk of the cow

1952 ◽  
Vol 42 (4) ◽  
pp. 403-412 ◽  
Author(s):  
R. Chanda ◽  
E. C. Owen
Keyword(s):  
Post Partum ◽  
Skim Milk ◽  
P Fractions ◽  
Mature Milk ◽  
Inorganic P ◽  
Minimum Value ◽  
A Value ◽  
Total P

The partitions of phosphorus and aneurin were determined in the colostrum and in the transitional and mature milk of Ayrshire cows with the following results:1. The ratio of nitrogen to phosphorus was 11:1 in the first mammary secretion but dropped to a minimum value of 4·5:1 a week later. Thereafter the ratio increased throughout lactation attaining a value of 7·2:1 at the fortieth week. The first colostrum was very rich in both phosphorus and nitrogen.2. Phosphatase titre in colostrum was 154 units in the first post-partum secretion but decreased to 10 during the first five days of lactation. The titre fluctuated slightly during the next few days and increased gradually thereafter, attaining 189 units in the 38th week of lactation.3. Phosphatase was correlated positively with inorganic-P (r= +0·83) and negatively with both ester-P (r= −0·94) and lipid-P (r= −0·70), all P fractions being expressed as percentages of total P. The percentage of phosphorus present as casein was initially 19–21%, but was only 14% in late lactation.4. The first colostrum contained 74 μg. aneurin/100 ml. skim milk. This value became 35 in midlactation and only 28 in late lactation. The corresponding figures for cocarboxylase were 20, 5·7 and 2·3 μg./100 ml. respectively, and for protein-bound aneurin 14, 3·2 and 1·7 respectively. Both cocarboxylase and protein-bound aneurin were negatively correlated with phosphatase.

Partnerships Generate Co-Benefits in Agricultural Stream Restoration (Canterbury, New Zealand)

2020 ◽  
Vol 4 (1) ◽  
Author(s):  
Catherine M. Febria ◽  
Maggie Bayfield ◽  
Kathryn E. Collins ◽  
Hayley S. Devlin ◽  
Brandon C. Goeller ◽  
...  
Keyword(s):  
New Zealand ◽  
Large Scale ◽  
Agricultural Land ◽  
Indigenous Rights ◽  
Freshwater Ecosystem ◽  
Reduced Pressure ◽  
Ecosystem Integrity ◽  
Riparian Management ◽  
Scale Change ◽  
Large Scale Change

In Aotearoa New Zealand, agricultural land-use intensification and decline in freshwater ecosystem integrity pose complex challenges for science and society. Despite riparian management programmes across the country, there is frustration over a lack in widespread uptake, upfront financial costs, possible loss in income, obstructive legislation and delays in ecological recovery. Thus, social, economic and institutional barriers exist when implementing and assessing agricultural freshwater restoration. Partnerships are essential to overcome such barriers by identifying and promoting co-benefits that result in amplifying individual efforts among stakeholder groups into coordinated, large-scale change. Here, we describe how initial progress by a sole farming family at the Silverstream in the Canterbury region, South Island, New Zealand, was used as a catalyst for change by the Canterbury Waterway Rehabilitation Experiment, a university-led restoration research project. Partners included farmers, researchers, government, industry, treaty partners (Indigenous rights-holders) and practitioners. Local capacity and capability was strengthened with practitioner groups, schools and the wider community. With partnerships in place, co-benefits included lowered costs involved with large-scale actions (e.g., earth moving), reduced pressure on individual farmers to undertake large-scale change (e.g., increased participation and engagement), while also legitimising the social contracts for farmers, scientists, government and industry to engage in farming and freshwater management. We describe contributions and benefits generated from the project and describe iterative actions that together built trust, leveraged and aligned opportunities. These actions were scaled from a single farm to multiple catchments nationally.

A New Large Scale Technic for Quantitative Recovery of Enteroviruses by Adsorption on Suspended Glass Powder. Application to Surface and Drinking Waters of the Paris Area

1982 ◽  
Vol 14 (4-5) ◽  
pp. 281-290
Author(s):  
Ph Vilaginès ◽  
B Sarrette ◽  
C Danglot ◽  
R Vilaginès
Keyword(s):  
River Water ◽  
Surface Waters ◽  
Large Scale ◽  
Glass Powder ◽  
Virus Concentration ◽  
Drinking Waters ◽  
Paris Area ◽  
New Apparatus ◽  
Quantitative Recovery

The aim of this work is to describe a new and inexpensive glass powder apparatus allowing virus concentration from 500 1 sample of water (10). Its efficiency was determined by analysis of drinking and surface waters preinoculated by Poliovirus. The detection of viruses from river water is compared when 500 1 (new apparatus) or 10 1 (preceeding apparatus) (7) are processed. The proposed new 500 1 apparatus allowed the recuperation of viruses in 100 % of the analysed samples the 10 1 one allowing their recuperation in only 50 % samples. This method was applied to the virus determination in the surface and drinking waters of the Paris area.

“Community Interests” and the Role of International Law in the Creation of a Global Market for Agricultural Land

2018 ◽  
Author(s):  
Jochen von Bernstorff
Keyword(s):  
International Law ◽  
Large Scale ◽  
Agricultural Land ◽  
Food Sovereignty ◽  
Global Market ◽  
Negative Consequences ◽  
Cultural Rights ◽  
Land Grab ◽  
Large Scale Land ◽  
The One

The chapter explores the notion of “community interests” with regard to the global “land-grab” phenomenon. Over the last decade, a dramatic increase of foreign investment in agricultural land could be observed. Bilateral investment treaties protect around 75 per cent of these large-scale land acquisitions, many of which came with associated social problems, such as displaced local populations and negative consequences for food security in Third World countries receiving these large-scale foreign investments. Hence, two potentially conflicting areas of international law are relevant in this context: Economic, social, and cultural rights and the principles of permanent sovereignty over natural resources and “food sovereignty” challenging large-scale investments on the one hand, and specific norms of international economic law stabilizing them on the other. The contribution discusses the usefulness of the concept of “community interests” in cases where the two colliding sets of norms are both considered to protect such interests.

scholarly journals Leaching Rate of Polychlorinated Biphenyls (PCBs) from Marine Paint Chips

2021 ◽  
Author(s):  
Allen D. Uhler ◽  
Jeffery H. Hardenstine ◽  
Deborah A. Edwards ◽  
Guilherme R. Lotufo
Keyword(s):  
Polychlorinated Biphenyls ◽  
Surface Waters ◽  
Leaching Rate ◽  
Short Term ◽  
Aroclor 1254 ◽  
Maintenance And Repair ◽  
Potential Source ◽  
Vessel Bottom ◽  
Dissolved Phase ◽  
Over Time

AbstractPolychlorinated biphenyls (PCBs) were added to certain marine vessel bottom paints as a plasticizer to improve the adhesion and durability of the paint. The most common PCB formulation used to amend such paints was Aroclor 1254. Fugitive Aroclor-containing paint chips generated from vessel maintenance and repair operations represent a potential source of PCB contamination to sediments. Limited published studies indicate that Aroclor-containing paint is largely inert and exhibits low PCB leaching into water; however, the rate and degree of leaching of PCBs from paint chips have not been directly studied. This laboratory-based study evaluated the rate and extent of leaching of PCBs from paint chips into freshwater. The results of this investigation demonstrate that the rate of PCB dissolution from paint chips decreased rapidly and exponentially over time. Based on this study, it is estimated that the rate of leaching of PCBs from paint chips would cease after approximately 3 years of exposure to water. When all leachable PCBs were exhausted, it is estimated that less than 1% of the mass of PCBs in the paint chips was amenable to dissolution. The results of this experiment suggest that Aroclor-containing paint chips found in sediments are likely short-term sources of dissolved-phase PCB to pore or surface waters and that the majority of the PCBs in paint chips remain in the paint matrix and unavailable for partitioning into water. Graphic Abstract

scholarly journals What Drives Landowners to Resist Selling Their Land? Insights from Ethical Capitalism and Landowners’ Perceptions

Land ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 312
Author(s):  
Ruxandra Malina Petrescu-Mag ◽  
Hamid Rastegari Kopaei ◽  
Dacinia Crina Petrescu
Keyword(s):  
Large Scale ◽  
Critical Reflection ◽  
Agricultural Land ◽  
Urban Land ◽  
Land Conversion ◽  
Land Grabbing ◽  
Ethical Perspective ◽  
Land Acquisitions ◽  
Large Scale Land ◽  
Land Transactions

Foreign land grabbing is acknowledged as a phenomenon that generates disempowerment and dispossession of local farmers, human rights violations. Previous studies have revealed the lack of ethical benchmarks in foreign large-scale land transactions that raise moral concerns. It is evident that when resources are scarce and people depend on them, the balance between values and interests transforms itself into a dilemma. Within this context, the aims of the paper were to bring to the fore critical reflection on a more ethical perspective of large-scale land acquisitions and to extend the scant information on what factors determine landowners not to sell their land to foreigners to limit land grabbing. This context justifies the need for a critical reflection on a more ethical perspective of large-scale land acquisitions. Therefore, two objectives were set. The first one is to document the role of ethics in large-scale land transactions. Based on the land grabbing literature, authors selected a set of eight land grabbing narratives, most often interrelated and overlapping, that pose ethical considerations. The second objective is to reveal how well a set of variables can predict the “Resistance to sell” the land to foreigners even when an attractive price is offered. As ethics is a social construct, the analysis captured the stakeholders’ perspective on land grabbing. Therefore, a questionnaire was applied to a sample of 332 Romanian landowners from twelve randomly selected counties to reveal their perceptions. Partial least squares structural equation modeling (PLS-SEM) was used to observe how well a set of seven variables could predict landowners’ “Resistance to sell” their land to foreign buyers. The use of PLS-SEM was justified by the existence of single items and the need to examine many structural model relations. Results showed that the variables with the strongest contribution to the prediction of the dependent variable are the “Probability to join an association for farmers rights defense”, the “Importance of the land price offered by the potential foreign buyer”, and the “Perceived effect of agricultural land conversion to urban land”. Raising awareness on the importance of buyer attributes, increasing people’s perception of the negative effect of agricultural land conversion to urban land, or strengthening the state’s image as a necessary actor to limit land grabbing will increase landowners’ resistance to sell their land to foreigners. Finally, it can be inferred that, within this frame of discussion, ethics should be valued as a means to create economically viable and morally justifiable solutions for foreign large-scale land transactions.

scholarly journals Floral Plantings in Large-Scale Commercial Agroecosystems Support Both Pollinators and Arthropod Predators

Insects ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 91
Author(s):  
Eric G. Middleton ◽  
Ian V. MacRae ◽  
Christopher R. Philips
Keyword(s):  
Large Scale ◽  
Agricultural Land ◽  
Field Margins ◽  
Crop Fields ◽  
Pollinator Abundance ◽  
Arthropod Predators ◽  
Commercial Potato ◽  
Insect Populations ◽  
Beneficial Insect ◽  
Potato Crops

Beneficial insect populations and the services that they provide are in decline, largely due to agricultural land use and practices. Establishing perennial floral plantings in the unused margins of crop fields can help conserve beneficial pollinators and predators in commercial agroecosystems. We assessed the impacts of floral plantings on both pollinators and arthropod predators when established adjacent to conventionally managed commercial potato fields. Floral plantings significantly increased the abundance of pollinators within floral margins compared with unmanaged margins. Increased floral cover within margins led to significantly greater pollinator abundance as well. The overall abundance of arthropod predators was also significantly increased in floral plantings, although it was unrelated to the amount of floral cover. Within adjacent potato crops, the presence of floral plantings in field margins had no effect on the abundance of pollinators or predators, although higher floral cover in margins did marginally increase in-crop pollinator abundance. Establishing floral plantings of this kind on a large scale in commercial agroecosystems can help conserve both pollinators and predators, but may not increase ecosystem services in nearby crops.

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