Horticulture and The Environment

Horticulture is among the fastest growing agricultural activities in Australia; with production valued at A$3.2 billion in 1995. It is also the second largest agricultural industry, after meat. Yet while Australia's horticultural producers are intensive users of land, water and farm chemicals, few economic research efforts have investigated the environmental problems associated with fruit and vegetable production. Since the early 1990s, Australia's growing focus on sustainable agriculture has led to greater scrutiny of horticultural activities, revealing several important trends and issues. These include: high and growing domestic demand for and consumption of horticultural products; increasingly health and nutrition conscious consumers concerned more and more with the quality and safety of their food; the expanding share of Australia's horticultural exports going to Asia; and growing domestic and international pressure on policymakers to address agriculture-related environmental problems and to devise measures to promote more sustainable practices. The common outcome of these interrelated trends is further intensification of land use each year as producers convert land to fruit and vegetable farming from other, less valuable production, and as they open up new lands for fruits and vegetables, especially in the tropical north of the country. This expansion on the ground has been accompanied by a corresponding increase in water, fertiliser and chemical use. Research has identified two broad types of environmental problems linked to Australia's fruit and vegetable production practices: (1) pollution and contamination of soil, water, air and food resulting from the use of farm chemicals; and (2) degradation of natural resources, especially the deterioration in the available quantity and quality of soil and water. More recently, fruit and vegetable production has been indirectly associated with disturbance and reduction of biotopes and wildlife habitats (e.g. on the Great Barrier Reef) and with reduction in wildlife species and loss of biological and genetic diversity of plants and animals. After reviewing these linkages between horticultural production and the environment, this paper examines the types of environmental policies that local, state and national level policymakers are using to address environmental degradation caused by horticultural production. These approaches include persuasion, education, regulation, economic incentives and property rights systems.

Surface water pollution has become a hot issue in recent years in that deterioration of surface water quality has hampered the sustainable development of China's economy. Previous studies have analyzed regional changes of water pollutants, but very few have studied at a national scale. By analyzing 9 water quality parameters recorded at 422 sampling stations nationwide, this studies summarized the spatial and temporal variations of surface water quality in China in "11th Five-Year Plan" period. Research showed that China's surface water quality is improving. But, further deterioration in several areas cannot be ignored. Human activities including over-urbanization and farming exerted a negative impact on surface water quality. Though the water quality in the upstream of major rivers located in northwest China was relatively better than that of other areas, deterioration of surface water quality has begun to emerge in the area. Additionally, the surface water quality in southern China was better than that of northern China. But some studies indicated that surface water quality was likely to worsen at a high speed. It was also found that different water quality parameters are characterized by spatial and temporal variations. These studies pointed out, the government should pay more attention to in the areas where the water quality parameters significantly exceeded the national standards. These studies provides theoretical basis for the decision-making and implementation of macro-scale water quality control policies.

Human activities greatly impact surface water quality due to the emission of various pollutants associated with different water use sectors (e.g. irrigation, livestock, domestic, energy and manufacturing)1,2. In-stream concentrations are also strongly dependent on the dilution capacity of receiving waters, which is related to both the hydrological regime and surface water abstractions. Pollutant emissions, hydrological regimes and surface water abstractions are all projected to change into the future as a result of both (uncertain) climate change and socio-economic developments. Yet, quantitative projections of future surface water quality are sparse, particularly at the global scale.In this work, we apply a new high-resolution global surface water quality model (DynQual)3 to project water temperature (Tw) and total dissolved solids (TDS), biological oxygen demand (BOD) and fecal coliform (FC) concentrations for the time period 2005-2100, considering multiple scenarios that combine Representative Concentration Pathways (RCPs) with Shared-Socioeconomic Pathways (SSPs). Input from five general circulation models (GCMs) is used to force PCR-GLOBWB2, the hydrological model coupled to DynQual, to account for the large range of uncertainties inherent in the climatological projections.The mechanisms that drive patterns in future surface water quality are a complex balance between changes in pollutant emissions, the dilution capacity of streams and in-stream decay processes, which are strongly driven by water temperature, under global change. Patterns of both water quality improvement and deterioration exist, which vary greatly across world regions. Reductions in pollutant emissions across most of Western Europe, North America and East Asia drive trends towards surface water quality improvements, irrespective of climate and socio-economic scenario. Conversely, developing countries are more sensitive to (uncertain) climate and socio-economic changes, with surface water quality typically improving under SSP1-RCP2.6, a mixed response under SSP5-RCP8.5 and strong degradation under SSP3-RCP7.0. Changes to the hydrological cycle are particularly important for surface water quality in the Amazon basin, with substantial reductions in discharge projected under SSP3-RCP7.0 and SSP5-RCP8.5. These changes result in reduced dilution capacities of rivers and thus higher in-stream concentrations, for instance of TDS.Surface water quality deterioration occurs across Sub-Saharan Africa under all scenarios, albeit to different magnitudes, which substantially increases the number of people that are exposed to poor water quality. Under SSP3-RCP7.0, the “worst-case” scenario for all constituents considered in our study, 4.2 billion people will be exposed to surface water with unsafe levels of organic (BOD) pollution by 2100. With 1.5 billion (36%) of these people located in Sub-Saharan Africa, compared to 290 million (11%) in the historical reference period, we conclude that Sub-Saharan Africa will become the new hotspot of water quality issues.   

Identification of nonpoint source (NPS) pollution is essential for effective water management. In this study we used a combined approach of hierarchal cluster analysis (HCA) and positive matrix factorization (PMF) to identify NPS pollution for Huaihe River basin in China. NH3-N, COD, DO and pH were regularly monitored weekly over 2 years (2011–2012) from 27 monitoring stations subjected to high anthropogenic and natural changes. As identified by multiple correspondence analyses, the monitoring stations #3, #9 and #21 are located away from the rest of sites. HCA classified all the stations into 4 groups. PMF identified four factors on each group and each season. They were associated with the major causes of Huaihe River water quality deterioration resulted by discharges inputs from urban, agricultural and industrial land uses. Seasonal NPS pollution variation was found, and it is possibly linked with natural processes, for instance hydrological regime. This research work demonstrates the usefulness of PMF model for the identification of NPS pollution in surface waters. Furthermore, our study also shows that urban, agricultural and industrial land uses were the main factors impairing surface water quality, and limiting NPS pollution would be critical for enhancing surface water quality in the study area.

Good surface water quality is essential for safeguarding human water use activities and maintaining ecosystem health. Yet, our quantitative understanding of past developments in surface water quality is mostly predicated upon observations at monitoring stations that are discontinuous in both space and time. Furthermore, very little is known about how both climate and societal change will impact surface water quality in the future. Process-based models provide unique opportunities to simulate both past and future surface water quality with a consistent spatial and temporal resolution. Representing one of the attempts in the emerging field of large-scale surface water quality modelling, we have developed the dynamical water quality routing model (DynQual) to simulate water temperature (Tw) and total dissolved solids (TDS), biological oxygen demand (BOD) and fecal coliform (FC) concentrations at 5 arc-minute (10km) spatial resolution and with a daily timestep. The model is open-source (https://github.com/UU-Hydro/DYNQUAL) and is coupled to the global hydrological model PCR-GLOBWB2, although hydrological input can alternatively be prescribed as a forcing. The model also incorporates a high-resolution wastewater treatment dataset1 to more realistically account for the impact of these practices on pollutant delivery to surface waters, compared to country-level or regional average rates. DynQual has been applied and validated against observed in-stream concentrations for the historic period (1980 – 2019) using input from ISIMIP3a2, and used to project future surface water quality (up to 2100) under (uncertain) climate change and socio-economic developments using input from ISIMIP3b3. Based on these modelled results, we assess the spatial patterns, temporal variations and long-term trends in surface water pollutant concentrations to evaluate global water quality dynamics. Our results show that surface water quality issues exist across all world regions, with current multi-pollutant hotspots especially prevalent in northern India and eastern China. Recent trends towards surface water quality deterioration are most profound in the developing world, particularly Sub-Saharan Africa and southern Asia. Conversely, in highly developed economies, organic (BOD) and pathogen (FC) pollution have decreased over time primarily due to expansions and improvements in wastewater collection and treatment. Simulations of future water quality indicate that pollution will increasingly and disproportionately affect people living in developing countries, with a widening gap in exposure rates between rich and poor countries. In particular, the combination of surface water quality deterioration and demographic changes in Sub-Saharan Africa will establish this region as a new global hotspot of surface water pollution.    

IntroductionSo far, many studies have been conducted to evaluate the impact of input consumption pattern on energy, economic and environmental indicators in horticultural and greenhouse crops in Iran. A review of these studies shows that the causes of the current situation in the systems have not been investigated. These studies are mostly reporting the current situation and the interventions and their effect on improving the input consumption pattern in the sustainability of the system have not been considered by researchers. Also, studies showed that the study location and products do not fit well with the volume of production in the horticultural and greenhouse sector of the Iran. Therefore, in order to increase the effectiveness and future direction of studies in this field, this review study was conducted. In this article, Iranian horticultural and greenhouse production systems were reviewed and analyzed by reviewing the published articles between 2008 and 2018, using the PRISMA method. The PRISMA method is a well-known method for conducting systematic review studies. The PRISMA method includes following sections: background; objectives; data sources; study eligibility criteria, participants, and interventions; study appraisal and synthesis methods; results; limitations; conclusions and implications of key findings. In this article, 16 types of garden products and 6 types of greenhouse products were studied.Material and MethodsIn this study, the methods used to determine the status of energy consumption pattern, economic and environmental in horticultural and greenhouse crops were analyzed. For this purpose, the indicators of total energy consumption (TEI), energy efficiency (EUE), net energy (NE), energy efficiency (EP) were examined in the section of energy. The issue of sensitivity analysis of energy inputs was also examined and the highest values of t-statistic and MPP were reported for products. In some articles, data envelopment analysis method was used in systems performance analysis. The indicators used included technical efficiency (TE), pure technical efficiency (PTE), scale efficiency (SE) and energy saving target ratio (ESTR). The results of them were summarized and reported. In some studies, the method of artificial neural networks and Adaptive Neuro-Fuzzy Inference System were used. In general, in the present article, the challenges and risks in the methods used in previous studies were considered. The issue of sampling in the analysis of agricultural systems was discussed in detail and a new sampling procedure was proposed. To draw a general picture of energy and environmental indicators of orchard and greenhouse systems in Iran, the results published in the articles were reviewed. Not all researchers use the same equivalents in calculating the indices, and this makes the results of the studies slightly different from each other. The existence of such differences causes some deviations in comparing the results of similar articles in the same products. However, to adjust for these differences, averaging was used in the index report.Results and DiscussionThe study of the share of inputs in the total energy consumption shows that in horticultural products, the share of fertilizer and electricity inputs is very significant. In the case of greenhouse products, fuel input, which is mainly diesel, has the largest share of energy consumption. Walnuts have the lowest energy consumption and strawberries have the highest energy consumption among orchard products. Grapes, apples and walnuts also have positive net energy, so they have the highest energy efficiency compared to other products. The most important inputs that have the greatest potential for energy savings in most products are diesel fuel and electricity. Among greenhouse crops in cucumber production, diesel fuel has great potential for energy savings that need to be reduced in future research. In the case of strawberry and rose, electricity input has the greatest potential for energy savings. Knowing the potential of inputs that can be saved can be effective in changing the behavior of producers.ConclusionsTo increase the effectiveness of research in this area, such studies should be done dynamically and for at least two or more years. In the first year, the input consumption pattern should be extracted and after performing the consumption pattern modifying interventions, the effect of these actions should be evaluated in the following years. Data envelopment analysis methods and multi-objective genetic algorithm can be well used to develop solutions to improve input consumption pattern. The review of articles showed that the study of the effect of social factors on the behavior of various production systems has been neglected. Since the pattern of energy consumption in the agricultural sector is significantly dependent on the behavior of users and the characteristics of systems and methods of production, it seems necessary to pay attention to this factor to prepare and design any process improvement strategy in the system. In this study, a new procedure including three stages of analysis, redesign and evaluation was proposed to complete the studies related to the analysis of agricultural systems.

Uganda has a largely agrarian based economy with 85% of its nearly 35 million people living in rural areas and 80% of its labor force engaged in agricultural production as their primary form of livelihood. The agriculture sector also accounts for 40 percent of GDP and 85% of export earnings with 90% of this being generated by crop production. Horticultural production is one of the fastest growing agricultural sub-sectors with a growth rate of 20% per year. It contributes to value addition, income diversification and foreign exchange earnings through exports (UIA, 1999). Horticultural production in Uganda is dominated by small scale producers (2ha. or less) who produce for both local and export markets. The most important horticultural crops in the vegetable category include tomato, green beans, cowpea, pepper, onion, crucifers, and Amaranthas spp. Because of ravages of pests and diseases on these moderate to high value crops, pesticides are among the key inputs on these crops. The increased use of chemical pesticides on horticultural crops has raised a number of economic, ecological and health concerns. Economic concerns arise from the over reliance and use of chemical pesticides which increase the costs of production. Indiscriminate use of pesticides has resulted in ecological problems of common pests developing resistance, elimination of natural enemies and other beneficial arthropods, and environmental pollution. Human health concerns focus on risks from shortcomings in protective clothing, large deviations from recommended doses/situations, and excessive run-off into the soil and water sources. These concerns are exacerbated by poorly regulated internal markets for pesticides that have fostered usage of banned or outdated products; creating a situation that if not stopped will negatively impact on horticultural exports to countries with more stringent regulatory requirements for fresh crop produce. Meeting these food safety requirements has become a major challenge for the fresh produce export sector of many African countries. To ensure and maintain export compliance, grower and consumer safety, and environmental integrity; farmers, government and development partners are developing programmes designed to improve pesticides usage, regulation and management on horticultural crops. In this chapter, three important horticultural crops grown in Uganda-

Assessing environmental phosphorus status of soils in Mauritius following long-term phosphorus fertilization of sugarcane

Water quality is a critical aspect of environmental health, affecting ecosystems, human health, and economic activities. In recent years, increasing pollution from industrial, agricultural, and urban sources has raised concerns about the deterioration of water quality in surface water bodies. Therefore, this study investigated the spatio-temporal distribution of water elements, human health risks of surface water, and pollutant sources at the confluence of the Wei River and the Yellow River. Using 80 samples collected during both wet and dry seasons, the content of the 22 water chemistry indicators was tested. A statistical analysis, Piper diagram, and entropy water quality index were employed to analyze the chemistry indicator content, hydrochemical composition, and water environmental quality of the surface water in the area. Moreover, the health risk assessment model was utilized to evaluate the carcinogenic and non-carcinogenic health risks associated with heavy metal elements in surface water. Finally, correlation heatmaps and a principal component analysis were used to identify potential pollution sources in the study area. The results indicated that Cr(VI) and NH3-N were the main pollutants during the wet season, while surface water quality during the dry season was mainly influenced by F−. The hydrochemical type in the study area was mainly SO4Cl-CaMg. The health risk assessment revealed a high carcinogenic risk in the study area, with Cr(VI) being the primary heavy metal element contributing to health risks. The correlation and principal component analysis results show that the surface water environment in the study area was influenced by soil characteristics (soils containing F− in the Dalí region, soils containing heavy metals in the Tongguan region), native geological environment (mineral resources and terrain conditions), and industrial activities (ore smelting). This study identified the key pollution indicators, the priority control areas, and the extent of the human health impact of the surface water at the confluence of the Wei River and the Yellow River, guiding targeted management of surface water environments.

Bacterial contamination of water and its associated human health problems are of concern to most people because surface water diseases have troubled human populations for centuries. The aim of this research is to determine the effects of hydrochemistry of urban runoff on surface water quality in Enugu urban area. The water samples were collected from six major rivers in the study area (Ekulu, Asata, Aria, Idaw, Ayo and Ogbete river) with 13 stations of runoff measurement in Enugu urban area. Physico-chemical data was collected by dividing the basin into 13 sub-catchments areas and these were confined mainly within the existing layout. The water samples collected from various strategic points from the study area were analyzed through laboratory tests. The first layer consists of Physical, chemical, and microbiological parameter. These were summarized and imported for statistical analysis and data processing. The result shows that rivers in the study area were highly polluted. The average quantity of Faecal Coliform in Enugu urban River was 17066.67cfu, and average Total Coliform pollution 25400 cfu. These changes were as a result of human and animal excreta flushed into surface water via runoff. The study noted that the physical, chemical and microbiological parameter of the basin, as well as geographical dispositions, combined with anthropogenic factors, are strong causative factors of runoff which causes pollution in surface water quality in the study area. Physio-chemical characteristic shows the hydrochemistry properties of runoff and the extent of pollution in surface water in the study area. The work recommends that there should be effective enforcement of legislation and improve in construction of modernize drainage channel which will collect discharge instead of channelling waste to rivers.

Surface water pollution seriously restricts the development of the city and results in the citizens yearning for a better life. Mountainous cities have their own characteristics in surface water environment and pollution compared with those of plain cities due to their unique topography. In August and October 2019, surface water and sediments were collected in a typical river (Qingshuixi River) in the main urban area of Chongqing. These samples were analyzed for nutrients such as carbon, nitrogen, and phosphorus as well as other basic physicochemical indicators. The results showed that the surface water of the Qingshuixi River was inferior to Category V at present, and it was also at a serious pollution level according to the comprehensive pollution index evaluation system. Among all the water quality indices, NH4+ and TP showed the most serious pollution. The tributaries of the Qingshuixi River exhibited higher surface water quality than that of the main stream, and the water quality during the rainfall season was better than that during the non-rainy season. Pollution sources, tailwater/tributary inflow, and river self-purification capacity determined the spatial distribution of nutrients in the surface water of the mainstream of the Qingshuixi River. Point sources such as the direct discharge of source sewage and pollution overflow in the middle and lower reaches were the most important sources of surface water pollution in the mainstream of the Qingshuixi River. Non-point source pollution had a limited impact on water quality. The "sink" or "source" role transformation of river sediments would occur under different water volume conditions in the river, reflecting the complexity of endogenous pollution. Surface water quality of the main stream showed a gradual improvement tendency along the downstream due to the dilution of the tail water/tributary inflow and the increased self-purification capability of the surface water in the mountainous rivers due to the increased DO content. To summarize, this study suggests that the water environment of the Qingshuixi River should be improved in comprehensive ways, which might be reducing the input of point source pollution by the deployment of the municipal pipe network in key areas, upgrading the sewage treatment plants to decrease pollutant concentrations or fluxes or channel dredging at the reaches with low DO content, etc.

The use of pesticides in fresh food of plant origin (FFPO) such as horticulture products is widely known. Such broad implementation of pesticide can result in a tremendous usage of pesticides and, afterward, in intolerable levels of pesticide residues in the products. In this work, we analyzed the pesticide residues in FFPO - which include fruits, vegetables, and rice - from some provinces in Indonesia. These products are taken from the market as samples for this analysis and they were not washed before the test. The test for pesticide residues uses two kinds of tests, which are: Rapid Test Kit that gives the qualitative result (presence or absence of active ingredients residual) without showing the amount of pesticide residue itself; and laboratory test that gives a quantitative result of pesticide active ingredients residual. Lab test data analysis shows that 98.58% of total samples from 26 provinces do not contain or have residues under MRLs so that it is stated as achieving food safety requirements. The pesticide residues include Organophosphate, Carbamate, Pyrethroid, Organochlorine, N-Phenylpyrazole, and Neonicotinoid groups of pesticide. Considering the effect of pesticide (residue) on human health and to environmental sustainability, efforts to control pesticide use need to be continued.

Under the background of climate change and man-made alterations to the environment, there has been an increase in the frequency of droughts and the range of their impact. Droughts may give rise to a series of resource, environmental and ecological effects, i.e., water shortage, water quality deterioration, as well as the decrease in the diversity of aquatic organisms. This paper, above all, identifies the impact mechanism of drought on the surface water quality of the basin, and then systematically studies the laws of generation, transfer, transformation and degradation of pollutants during the drought, finding that the alternating droughts and floods stage is the critical period during which the surface water quality is affected. Secondly, through employing indoor orthogonality experiments, serving drought degree, rainfall intensity and rainfall duration as the main elements and designing various scenario models, the study inspects the effects of various factors on the nitrogen loss in soil, as well as the loss of nonpoint source pollution and the leaching rate of nitrogen under the different alternating scenarios of drought and flood. It comes to the conclusion that the various factors and the loss of nonpoint source pollution are positively correlated, and under the alternating scenarios of drought and flood, there is an exacerbation in the loss of ammonium nitrogen and nitrate nitrogen in soil, which generates the transfer and transformation mechanisms of nonpoint source pollution from a micro level.

During the last two decades Indian agriculture has been facing major challenges like deceleration in growth rate, inter-sectoral and inter-regional equity, declining input efficiency, degradation of natural resources, etc. with consequent adverse effects on food and nutritional security, food inflation and poverty reduction. However, the 11th Plan had some success in reversing the deceleration of agricultural growth witnessed during the 9th and 10th Plan but food inflation still remains a major concern. The growth in agriculture in the 11th Plan is likely to be around 3.2 percent per year, which is higher than 10th Plan growth rate but lower than the target (4.0%) for 11th Plan. The 12th Plan growth target for agriculture sector has been set at 4 percent with foodgrains growth at about 2 percent and non-foodgrains sector (horticulture, livestock and fisheries) growing at about 5-6 percent. However, looking at the growth in agriculture sector in general and high-value agriculture, particularly, horticulture, fisheries, dairy and meat sector during the 11th Plan, there is a need to put additional efforts to achieve 4 percent growth in agriculture. The failure to achieve targeted growth in agriculture has resulted from the inadequacies of the provision of the critical public goods such as research and development, extension services, surface irrigation, rural infrastructure, etc. on which agricultural growth thrives as well as inappropriate policies. In order to achieve the targeted growth in 12th Plan, we need to address some of these inadequacies. The sector would require substantial increase in investment both by public and private sector in agriculture research and development including extension, rural infrastructure, post-harvest and market infrastructure including storage and processing, reforms in laws related to land markets and marketing of agricultural products, and appropriate price policy. The pricing of agricultural inputs such as irrigation, electricity for pumping water, fertilizer, etc. needs rationalization. The distributional aspects of agricultural credit including inter-regional and inter-class inequalities in access to credit, decline in rural branches, declining share of direct credit, etc. must be addressed. People’s participation, which will help in promoting the bottom up approach of planning process and also help in faster diffusion of the technologies and best practices among farmers, community based actions and participation of disadvantaged sections of the society in developmental process, needs to be strengthened.

Significant research on surface water pollution modelling has been carried out over diverse landscapes has sought to explain the sources, transport, and surface water pollution. To date, surface water pollution studies have focused on nutrients, plastics, and chemicals. Consequently, the current review aims to identify and synthesise peer-reviewed literature about integrated contaminants modelling in surface water. Thus, highlighting that modelling potentially multiple sources of a pollutant from the surface water has remained a thought-provoking topic. Studies differed significantly in terms of the type of model application and procedures for reporting findings, making it challenging to separate clear trends and patterns. Accordingly, most studies agree that pollutants such as plastics and agrochemicals can have adverse consequences on surface water quality; these coincide with difficulties in modelling pollutant transport. Consequently, no regional or global estimates are available for the water pollution burden of flood-related pollution, considering the demonstrable modelling techniques, the significance of the concurrent impacts of surface water pollution by contaminants. Multi-pollutant approaches to modelling the potential sources of pollution and encourage protective behaviour are essential. Mainstreaming freshwater pollution concerns into planning strategies will also be needed to lessen anthropological contribution to surface water pollution. While the implementation of these models is constrained by lack of adequate field data, the model output must be analysed within the model inputs' uncertainty, data limitations and methodologically established surface water modelling principles from the literature.