Effects of Climate Conditions on TP Outsourcing in Lake Kinneret (Israel)

Since the mid-1980s, significant changes in climate conditions have occurred, and trends of dryness in the Kinneret drainage basin have been documented, including a temperature increase and precipitation decline. The precipitation decline, and consequently the reduction in river discharge, resulted in a decrease in TP (total phosphorus) flux into Lake Kinneret. After the drainage of the Hula natural wetlands and old Lake Hula during the 1950s, the ecological characteristics of the Hula Valley were modified. Nutrient fluxes downstream into Lake Kinneret were therefore predicted. The impacts of climate conditions (precipitation and discharge) on TP (total phosphorus) outsourcing through erosive action are significant: higher and lower discharge enhances and reduces TP load, respectively. The total TP flushing range from the Hula Valley peat soil through the subterranean medium and where TP is directed are not precisely known but are probably outside Lake Kinneret. Most runoff water and mediated TP originates from bedrock through erosive action. Long-term records of TP concentrations in headwaters and potential resources in the Hula Valley confirmed the significant influence of climate conditions on the outsourcing of TP capacity. The impacts of agricultural development, external fertilizer loads and migratory cranes in the winter are probably insignificant.

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Climate Change Controls Phosphorus Transport from the Watershed into Lake Kinneret (Israel)

10.1101/2021.03.16.435628 ◽

2021 ◽

Author(s):

Moshe Gophen

Keyword(s):

Climate Change ◽

Regional Climate ◽

Regional Climate Change ◽

Lake Kinneret ◽

Phosphorus Transport ◽

Efficient Management ◽

Hula Valley ◽

Reclamation Project ◽

The Impact

AbstractPart of the Kinneret watershed, the Hula Valley, was modified from wetlands – shallow lake for agricultural cultivation. Enhancement of nutrient fluxes into Lake Kinneret was predicted. Therefore, a reclamation project was implemented and eco-tourism partly replaced agriculture. Since the mid-1980s, regional climate change has been documented. Statistical evaluation of long-term records of TP (Total Phosphorus) concentrations in headwaters and potential resources in the Hula Valley was carried out to identify efficient management design targets. Significant correlation between major headwater river discharge and TP concentration was indicated, whilst the impact of external fertilizer loads and 50,000 winter migratory cranes was probably negligible. Nevertheless, confirmed severe bdamage to agricultural crops carried out by cranes led to their maximal deportation and optimization of their feeding policy. Consequently, the continuation of the present management is recommended.

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A long-term prediction model for total phosphorus concentrations in Lake Kinneret

Water Research ◽

10.1016/0043-1354(89)90062-6 ◽

1989 ◽

Vol 23 (1) ◽

pp. 61-66 ◽

Cited By ~ 13

Author(s):

G. Herman ◽

A. Nishri ◽

T. Berman

Keyword(s):

Prediction Model ◽

Total Phosphorus ◽

Lake Kinneret ◽

Term Prediction ◽

Long Term Prediction

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Climate Change-Enhanced Cyanobacteria Domination in Lake Kinneret: A Retrospective Overview

Water ◽

10.3390/w13020163 ◽

2021 ◽

Vol 13 (2) ◽

pp. 163

Author(s):

Moshe Gophen

Keyword(s):

Climate Change ◽

Water Quality ◽

Lake Water ◽

Drainage Basin ◽

Methodological Approach ◽

Nitrogen Deficiency ◽

Lake Kinneret ◽

Water Quality Deterioration ◽

Limnological Parameters

The objective of this study is re-evaluation of the long-term record of limnological parameters in Lake Kinneret (1970–2018) and its drainage basin (1940–2018) aimed at an indication of the possible impact of climate change on water quality in Lake Kinneret. The methodological approach is based on indication of significant changes, of temperature increase, decline in rainfall, causing a reduction in river discharges, and lake water inflows. These climatological changes were accompanied by a reduction in nitrogen and a slight increase in phosphorus in the lake Epilimnion. The outcome was Epilimnetic Nitrogen deficiency and Phosphorus sufficiency, which enhanced domination replacement of Peridinium spp. by Cyanobacterial. We concluded sequel suggested climate change affected water quality deterioration in Lake Kinneret.

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Lake Paranoá, Brasília, Brazil: Integrated Management Plan for its Restoration

Water Quality Research Journal ◽

10.2166/wqrj.1992.019 ◽

1992 ◽

Vol 27 (2) ◽

pp. 271-286 ◽

Cited By ~ 4

Author(s):

Sonia Paulino Mattos ◽

Irene Guimarães Altafin ◽

Hélio José de Freitas ◽

Cristine Gobbato Brandão Cavalcanti ◽

Vera Regina Estuqui Alves

Keyword(s):

Total Phosphorus ◽

Drainage Basin ◽

Integrated Management ◽

Algal Growth ◽

Nutrient Content ◽

Management Plan ◽

Cylindrospermopsis Raciborskii ◽

Phosphorus Concentration ◽

Limiting Factor ◽

Total Phosphorus Concentration

Abstract Built in 1959, Lake Paranoá, in Brasilia, Brazil, has been undergoing an accelerated process of nutrient enrichment, due to inputs of inadequately treated raw sewage, generated by a population of 600,000 inhabitants. Consequently, it shows high nutrient content (40 µg/L of total phosphorus and 1800 µg/L of total nitrogen), low transparency (0.65 m) and high levels of chlorophyll a (65 µg/L), represented mainly by Cylindrospermopsis raciborskii and sporadic bloom of Microcystis aeruginosa, which is being combatted with copper sulphate. With the absence of seasonality and a vertical distribution which is not very evident, the horizontal pattern assumes great importance in this reservoir, in which five compartments stand out. Based on this segmentation and on the identification of the total phosphorus parameter as the limiting factor for algal growth, mathematical models were developed which demonstrate the need for advanced treatment of all the sewage produced in its drainage basin. With this, it is expected that a process of restoration will be initiated, with a decline in total phosphorus concentration to readings below 25 µg/L. Additional measures are proposed to accelerate this process.

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Long-term estimation of the canopy photosynthesis of a leafy vegetable based on greenhouse climate conditions and nadir photographs

Scientia Horticulturae ◽

10.1016/j.scienta.2021.110433 ◽

2021 ◽

Vol 289 ◽

pp. 110433

Author(s):

Koichi Nomura ◽

Daisuke Yasutake ◽

Takahiro Kaneko ◽

Tadashige Iwao ◽

Takashi Okayasu ◽

...

Keyword(s):

Leafy Vegetable ◽

Canopy Photosynthesis ◽

Climate Conditions ◽

Greenhouse Climate

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Agriculture and land use in the North of Russia: Case study of Karelia and Yakutia

Open Geosciences ◽

10.1515/geo-2020-0210 ◽

2020 ◽

Vol 12 (1) ◽

pp. 1497-1511

Author(s):

Alexey Naumov ◽

Varvara Akimova ◽

Daria Sidorova ◽

Mikhail Topnikov

Keyword(s):

Land Use ◽

Agricultural Development ◽

Agricultural Land ◽

Geographical Location ◽

Special Role ◽

Sources Of Information ◽

Local Conditions ◽

Climate Conditions ◽

The North ◽

The Republic

AbstractDespite harsh climate, agriculture on the northern margins of Russia still remains the backbone of food security. Historically, in both regions studied in this article – the Republic of Karelia and the Republic of Sakha (Yakutia) – agricultural activities as dairy farming and even cropping were well adapted to local conditions including traditional activities such as horse breeding typical for Yakutia. Using three different sources of information – official statistics, expert interviews, and field observations – allowed us to draw a conclusion that there are both similarities and differences in agricultural development and land use of these two studied regions. The differences arise from agro-climate conditions, settlement history, specialization, and spatial pattern of economy. In both regions, farming is concentrated within the areas with most suitable natural conditions. Yet, even there, agricultural land use is shrinking, especially in Karelia. Both regions are prone to being affected by seasonality, but vary in the degree of its influence. Geographical location plays special role, and weaknesses caused by remoteness to some extent become advantage as in Yakutia. Proximity effect is controversial. In Karelia, impact of neighboring Finland is insignificant compared with the nearby second Russian city – Saint Petersburg.

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Agricultural Support Policies and China’s Cyclical Evolutionary Path of Agricultural Economic Growth

Sustainability ◽

10.3390/su13116134 ◽

2021 ◽

Vol 13 (11) ◽

pp. 6134

Author(s):

Xiangdong Guo ◽

Pei Lung ◽

Jianli Sui ◽

Ruiping Zhang ◽

Chao Wang

Keyword(s):

Agricultural Economic ◽

Agricultural Development ◽

Animal Husbandry ◽

Agricultural Policies ◽

Growth Trend ◽

Agricultural Economy ◽

Growth Status ◽

Growth Regime ◽

Agricultural Support

Due to the weak nature of agricultural production, governments usually adopt supportive policies to protect food security. To discern the growth of agriculture from 2001 to 2018 under China’s agricultural support policies, we use the nonlinear MS(M)-AR(p) model to distinguish China’s agricultural economic cycle into three growth regimes—rapid, medium, and low—and analyze the probability of shifts and maintenance among the different regimes. We further calculated the average duration of each regime. Moreover, we calculated the growth regime transfers for specific times. In this study, we find that China’s agricultural economy has maintained a relatively consistent growth trend with the support of China’s proactive agricultural policies. However, China’s agricultural economy tends to maintain a low-growth status in the long-term. Finally, we make policy recommendations for agricultural development based on our findings that continue existing agricultural policies and strengthen support for agriculture, forestry, and animal husbandry.

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To the problem of uncertainty in interpolation of annual runoff

Hydrology Research ◽

10.2166/nh.2012.073 ◽

2012 ◽

Vol 43 (6) ◽

pp. 833-850 ◽

Cited By ~ 5

Author(s):

Ziqi Yan ◽

Lars Gottschalk ◽

Irina Krasovskaia ◽

Jun Xia

Keyword(s):

Cross Validation ◽

Drainage Basin ◽

Annual Runoff ◽

Mean Value ◽

Regular Grid ◽

Main River ◽

Average Annual Runoff ◽

The One ◽

Better Than

The long-term mean value of runoff is the basic descriptor of available water resources. This paper focuses on the accuracy that can be achieved when mapping this variable across space and along main rivers for a given stream gauging network. Three stochastic interpolation schemes for estimating average annual runoff across space are evaluated and compared. Two of the schemes firstly interpolate runoff to a regular grid net and then integrate the grid values along rivers. One of these schemes includes a constraint to account for the lateral water balance along the rivers. The third scheme interpolates runoff directly to points along rivers. A drainage basin in China with 20 gauging sites is used as a test area. In general, all three approaches reproduce the sample discharges along rivers with postdiction errors along main river branches around 10%. Using more objective cross-validation results, it was found that the two schemes based on basin integration, and especially the one with a constraint, performed significantly better than the one with direct interpolation to points along rivers. The analysis did not allow identification of possible influence of surface water use.

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Long-term changes of the ice regime of rivers in Latvia

Hydrology Research ◽

10.2166/nh.2016.012 ◽

2016 ◽

Vol 47 (4) ◽

pp. 782-798

Author(s):

Inese Latkovska ◽

Elga Apsīte ◽

Didzis Elferts

Keyword(s):

Regional Differences ◽

Severity Index ◽

Ice Cover ◽

Ice Thickness ◽

Positive Trend ◽

The West ◽

Climate Conditions ◽

Long Term Changes ◽

Ice Regime

The ice regime of rivers is considered a sensitive indicator of climate change. This paper summarises the results of research on the long-term changes in the ice regime parameters under changing climate conditions and their regional peculiarities in Latvia from 1945 to 2012. The ice cover duration on Latvian rivers has decreased during recent decades. The research results demonstrated that there is a positive trend as regards the formation of the ice cover and in 31.8% of the cases the trend is statistically significant at p < 0.05. As regards the breaking up of ice, there is a statistically significant negative trend in 93.2% of the cases at p < 0.05. This indicates an earlier ice break-up date, which in turn, displays a strong correlation with the increase of the air temperature. The same pattern applies to the reduction of the length of ice cover (a statistically significant trend in 86.4% of the cases at p < 0.05). In approximately 60% of the cases, there is a statistically significant reduction of the ice thickness. The estimated winter severity index indicates warmer winters over the last 20 years as well as regional differences in the west–east direction.

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