Northwestern Coastal Region Research Articles

Assessment the impacts of land cover and climate changes on rainwater harvesting systems using remote sensing and runoff model in some Wadis of West Matrouh – Egypt

The aim of this study is to evaluate the potential changes in land cover and their impacts on rainwater harvesting systems, with a focus on Egypt's northwestern coastal region. To accomplish this objective, we utilized the kinematic runoff and erosion model (KINEROS2) to estimate the effects of projected land use changes on runoff and sediment load. The results demonstrated satisfactory performance of the model, with average Nash-Sutcliffe Efficiency values of 0.75 for calibration and 0.77 for validation, indicating successful simulations. The analysis revealed that land use changes had minimal impact in the base scenario (S1), resulting in moderate fluctuations in estimated sediment load. Conversely, the supplementary scenarios (S2 and S3) exhibited more pronounced alterations in land use, resulting in significant deviations in model estimations, notably indicating a substantial reduction in soil erosion. The integration of land use change analysis with KINEROS2 modeling emphasizes the potential for implementing effective management strategies.

Clarification of the Lopingian palaeoclimatic conditions of the northwestern coastal regions of Palaeotethys based on the Transdanubian geological record

The Lopingian sedimentary rocks of South and South-Central Europe play an important role in reconstructing the same-age equatorial climate of the Pangea. However, geological evidence suggests a mismatch between the previously supposed equatorial monsoonal, tropical summer wet climate and the more arid Lopingian climatic conditions. To clarify the Lopingian climate of the northwest coastal region of the Palaeotethys, palynofloral assemblages and the climatic background behind the occurrence of soil, aridity, biome, and vegetation patterns of present-day arid and semi-arid territories were studied. In contrast to the similar lithological characters and the proposed Lopingian geographical proximity of the Southern Alpine and Transdanubian sequences, notable differences exist between the palynofloras of these regions. While the conifer-dominated, low-diversity Transdanubian flora belonged to the tropical, the more diverse Southern Alpine flora was part of the Permian Euramerican floral kingdom. Based on the occurrence of modern conifers, it is not plausible that Permian ones occupied arid regions. However, the current distribution of juvenile anhydrite, gypsisols and calcisols shows that the similar palaeosoils of the South Alpine and Transdanubian formations were formed in a tropical desert biome. By synthesizing the evidence exhibited above, it can be concluded that arid and semi-arid environments existed along the northwestern margin of the Palaeotethys and the humid, monsoonal regions were restricted to the Hercynian ranges. Local hydrological conditions plausibly had a notable impact on the occurrence of plant taxa in semi-arid regions which can explain the differences in the palynoflora despite the similar palaeoclimates.

An integrative assessment of the plastic debris load in the Mediterranean Sea.

The Mediterranean Sea is recognized as one of the most polluted areas by floating plastics. During the Tara Mediterranean expedition, an extensive sampling of plastic debris was conducted in seven ecoregions, from Gibraltar to Lebanon with the aim of providing reliable estimates of regional differences in floating plastic loads and plastic characteristics. The abundance, size, surface, circularity and mass of 75,030 pieces were analyzed and classified in a standardized multi-parameter database. Their average abundance was 2.60 × 105 items km-2 (2.25 × 103 to 8.50 × 106 km-2) resulting in an estimate of about 650 billion plastic particles floating on the surface of the Mediterranean. This corresponds to an average of 660 metric tons of plastic, at the lower end of literature estimates. High concentrations of plastic were observed in the northwestern coastal regions, north of the Tyrrhenian Sea, but also off the western and central Mediterranean basins. The Levantine basin south of Cyprus had the lowest concentrations. A Lagrangian Plastic Pollution Index (LPPI) predicting the concentration of plastic debris was validated using the spatial resolution of the data. The advanced state of plastic degradation detected in the analyses led to the conclusion that stranding/fragmentation/resuspension is the key process in the dynamics of floating plastic in Mediterranean surface waters. This is supported by the significant correlation between pollution sources and areas of high plastic concentration obtained by the LPPI.

Australian sub‐regional temperature responses to volcanic forcing: A critical analysis using CMIP5 models

AbstractIt is now well established that global to local climate is impacted by volcanic forcing associated with major eruptions. Much attention has been given to the way in which climate is affected by such eruptions, particularly for the Northern Hemisphere, and to a considerably lesser extent for the Southern Hemisphere. Research knowledge gaps remain on such forcing impacts at finer sub‐regional spatial scales. To this end, we explore temperature responses across eight sub‐regions of Australia following three major volcanic eruptions (i.e., Krakatau, 1883; Santa Maria, 1902; Pinatubo, 1991) as simulated by CMIP5 models. We then compare such responses with station and reanalysis datasets. Model outputs indicate strongest temperature responses over more northerly regions than southerly regions of Australia, with weakest responses over Tasmania. Eastern regions of Australia seem to have strongest seasonal cooling during austral autumn, while that for northwestern coastal regions is during austral winter. In contrast, central regions of Australia cool most substantially during austral summer and/or winter, depending on the eruption. Despite such variability, initial temperature responses occur during the warmer austral months (September to February). Uncertainties exist in the reliability of CMIP5 data. For instance, temperature responses from the later Pinatubo eruption seem in stronger agreement with reanalysis data than earlier eruptions (Krakatau and Santa Maria), and while most seasonal temperature responses are stronger than those provided through reanalysis data, they are often weaker in austral spring.

Developing spatial model to assess agro-ecological zones for sustainable agriculture development in MENA region: Case study Northern Western Coast, Egypt

The development of Agro-Ecological Zones (AEZs) is a vital step in sustainable agricultural development. This study proposes a quantitative method for developing the AEZs and land suitability for Wadi El-Grawla, North-Western Coastal Region (NWCR), Egypt. Hundreds of surface soil samples and twenty soil profiles covering the variations in the study area were collected; then, the inverse distance weighted (IDW) interpolation technique was utilized to produce representative maps for different soil characteristics. Moreover, a digital elevation model (DEM) was generated from topographic maps to calculate various land surface factors such as slope, curvature, and relief density. In addition to benefiting from Sentinel-2 imagery in the separation process of different landform units with a classification accuracy of about 87%. Two soil orders were identified in the study area, namely, Aridisols and Entisols. Chemical analysis of soil samples revealed that soil pH range from 7.14 to 8.6. Total soluble salt changes widely from one location to another. Calcium carbonate (CaCO3) has a wide range of 3.5–31.5%. Organic matter (OM) ranges between 0.04 and 1.55%. A weighted overlay of obtained thematic maps resulted in three management zones in the Wadi El-Grawla area. Zone-1 represents the best location, with an area of about 2359.3 ha. At the same time, the regions of the area of zone-2 and zone-3 are 2526.4 ha and 1346.8 ha, respectively. Finally, suitability maps were produced for the most strategic crops cultivated in Wadi El-Grawla. The most suitable classes were S2 and S3 for all studied crops. The obtained results will support the decision-makers to put various development plans according to the conditions of the study area.

Vegetation Dynamics, Environmental Changes, and Anthropogenic Impacts on the Coastal Hyrcanian Forests in Northern Iran

Gu, F.; Ramezani, E.; Alizadeh, K., and Behling, H., 2021. Vegetation dynamics, environmental changes, and anthropogenic impacts on the coastal Hyrcanian forests in northern Iran. Journal of Coastal Research, 37(3), 611–619. Coconut Creek (Florida), ISSN 0749-0208.The Hyrcanian forest has been recognized as a hotspot of biodiversity and an important refugium of broad-leaved trees that survived from Quaternary ice ages. However, nowadays this coastal ecosystem has been endangered due to increased anthropogenic impacts. Multiproxy analysis, including pollen, spores, nonpollen palynomorphs, macrocharcoal, and X-ray fluorescence analysis have been applied on a sediment core from the northwestern coastal region of Iran, Zarbijar wetland to reconstruct past vegetation, regional climate dynamics, fire events, and human impacts on the coastal region of Hyrcanian forest. This study provides evidence that the anthropogenic impacts have greatly influenced the ecosystems of the coastal plain of the southern Caspian Sea during the last 600 years and demonstrate that human activities became intensified in the last 100 years. It is suggested that due to the human activities by construction, the geochemical composition of the wetland deposits was markedly artificially changed. The study also indicates that the dynamics of the Hyrcanian lowland forests and local fire frequency were mainly codominated by human impact and local climate conditions. Increased anthropogenic activities such as agriculture, construction, and human-induced fires played an important role in the decline of the Hyrcanian forest. Therefore, this study also suggests that more effort is urgently needed to protect this unique global heritage, and that not only the local government but also the international forest conservation agencies should introduce certain effective corresponding policies to prevent deforestation, control the expansion of land use by agricultural, and construction.

A minimum data set of soil morphological properties for quantifying soil quality in coastal agroecosystems

Soil quality in coastal agroecosystems changes rapidly owing to coastal dynamics and land-use change. The potential of soil morphological properties as soil quality indicators is mostly unexplored. We present a minimum data set (MDS) of soil morphological properties to quantify the coastal soil quality. We compiled a dataset including 18 soil morphological properties from 468 soil profiles, representing five land-use types (plantation crops, sugarcane, grassland, rice, and cotton + pigeon pea) of the north-western coastal region of India. The categorical variables were transformed into numerical variables using the optimal scaling method, and categorical principal component analysis (CATPCA) was used to identify the MDS. The CATPCA produced five principal components explaining 60% of the variability. The MDS comprises pore abundance, structure size, drainage, pore size, and colour (value) with 32, 22, 21, 14, and 12% contribution to soil quality, respectively. The morphological soil quality index (MSQI) varied from 0.26 to 0.99 for surface soils, and from 0.11 to 0.94 for the subsurface soils. Among the land-use types, the rice-growing soils were low in their morphological quality due to structural degradation. Land-use types significantly influenced the MSQI in both surface and subsurface soils, and hence, we recommend the inclusion of subsurface soils for soil quality evaluation. The strong relationship of MSQI with saturated hydraulic conductivity (R2 = 0.56) validated the suitability of the MDS for assessment of soil quality by the farmers, and non-experts in the coastal regions. Further, the higher variability explained by the soil morphology data indicates that the MDS identified in this study could be effectively used to evaluate soil quality in areas with limited data.

Flavonoids content of 70% methanolic extract of Erucaria pinnata (Viv.) and its effect as anticancer and antiangiognic: in vitro, in vivo and docking study

Erucaria pinnata (Viv.) is a wild annual plant growing in North-Western Coastal Region in Egypt. This study reports for the first time the cytotoxic activity of different extracts of Erucaria pinnata plant against HEP-G2 cell line. The 70% methanolic extract (E1) recorded the best potent cytotoxic activity (IC50=13.6 µg/ml), so we analysis the flavonoids constituent of this extract using HPLC, which show that our extract is rich with important flavonoids compounds (rutin, quercetin, leutolin, etc.). We evaluated its antitumor activity against hepatocellular carcinoma (HCC) induced by diethylnitrosamine (DEN) (200mg/Kg. b.wt., i.p, single dose) after two weeks, animals received carbontetrachloride (CCl4) (3ml/Kg. b.wt., SC, once a week for 6 weeks) and the experiment continued for 44 weeks in rats. After the experimental period, the administration of DEN/CCl4 showed significant increase in the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin, gamma-glutamyl transferase (γGT) and significant decrease in the levels of total proteins and albumin content in the serum with reduction in the liver antioxidants, including superoxide dismutase (SOD) and catalase (CAT). This was accompanied by increases in serum specific tumor markers (AFP). The 70% methanolic plant extract (E1) was orally administrated (400mg/kg/day respectively) for the whole study period, and it showed a significant improvement at the different biological liver functions, remodeled the antioxidant enzymes activity and down-regulated the serum AFP. All these findings were confirmed by histopathological studies of the liver samples obtained from all groups. In addition, we evaluated its antiangeogenic activity by docking study against VEGFR-2 tyrosine kinase after it showed an ability to inhibit the VEGFR-2 expression in vitro and inhibit the concentration of VEGF-A in vivo. The hepatoprotective effect of our extract was attributed to its antioxidant and antiangeogenic activity.

Understanding the influence of urbanization on invasibility: Carpobrotus edulis as an exemplar

Coastal dune areas are valuable ecosystems, generally impacted by habitat destruction and invasive alien species. In this study, we assessed how human disturbance and invasion by Carpobrotus edulis impact the soils and the establishment of native flora in the north-western coastal regions of Spain. We compared soil characteristics (pH, conductivity, water content, nutrients and enzymatic activities) and native plant as well as C. edulis fitness correlates (germination and early growth) between uninvaded and invaded soils from urban and natural coastal dune areas. We found that human disturbance impacts coastal soils by increasing organic matter and water content, modifying soil nutrients and cycles, and reducing the pH in urban soils. The presence of invasive C. edulis further increases these impacts. These changes in soil characteristics allow for the establishment of the native, but ruderal, Scolymus hispanicus and non-native C. edulis, both of which are not adapted to the typically limiting conditions of coastal dunes. In some instances, the coastal dune endemic, Malcolmia littorea, showed no fitness effects in response to urbanization or the presence of C. edulis. These results suggest that human disturbed coastal areas might be more easily invaded than natural areas. More broadly, our findings of differential responses of different native species to disturbance and invasion, illustrate the need for multi-taxon approaches when assessing the impacts of invasive species.

Mitochondrial D-loop sequences reveal a mixture of endemism and immigration in Egyptian goat populations

The mitochondrial D-loop region was used to investigate genetic diversity within and between populations of Egyptian goats, to elucidate processes that explain present patterns of diversity and differentiation and to characterize Egyptian goats relative to international breeds. A total of 120 animals from six populations were sampled. Results confirm the main trend from previous studies of mtDNA diversity in goats, with high levels of diversity within populations, but with a comparative lack of genetic structure supporting geographic distribution. Haplotype diversity varied in a narrow range whereas nucleotide diversity values were more informative in showing differences between populations. The majority of goats analyzed (93.2%) displayed haplotypes that group with Haplogroup A, the most common type found in global goat populations. The remaining animals grouped with the less common Haplogroup G. Population differentiation analysis showed some uniqueness in the Aswan and Sharkawi populations from the South and East of Egypt. Overall, the structure of the Egyptian goat population is characterized by a high degree of homogeneity among populations from the north-western coastal region, the Nile Delta and the upper and middle regions of the Nile valley, but with possible introgression of rarer haplotypes into populations at the southern and eastern extremities of the country.

Four new species of Rasbora of the Sumatrana group (Teleostei: Cyprinidae) from northern Sumatra, Indonesia.

Four new species of the minnow genus Rasbora of the Sumatrana group, R. arundinata, R. haru, R. maninjau, and R. bindumatoga, are described from northern Sumatra. Rasbora arundinata is distinguished from all congeners in the Sumatrana group by the black midlateral stripe overall forming a reed-leaf-like profile. Rasbora haru differs from its congeners in the Sumatrana group in having the black midlateral stripe overall forming a stamen-like profile. The new species endemic to Lake Maninjau in central west Sumatra, Rasbora maninjau, is unique among all the congeners in the Sumatrana group in having a combination of the black midlateral stripe extending from the midhumeral region of uniform width, the prominent acutely triangular basicaudal blotch, and the oval supra-anal pigmentation. Rasbora bindumatoga is distinguished from all congeners in the Sumatrana group by a combination of the black rectangular subdorsal blotch, the absence of supra-anal pigmentation, and the somewhat oval basicaudal blotch. Rasbora arundinata, R. maninjau, and R. bindumatoga occur allopatrically in the northwestern coastal region of Sumatra, while R. haru is known from northeastern coastal area of Sumatra. A new diagnostic character for the Sumatrana group is described: partial exposure of the upper lip due to a submedial contact between the maxilla and the lower lip, which is marked posteriorly by a lachrymal groove.

Regional Differences of Hydrographical and Sedimentological Properties in the Beibu Gulf, South China Sea

Bauer, A.; Radziejewska, T.; Liang, K.; Kowalski, N.; Dellwig, O.; Bosselmann, K.; Stark, A.; Xia, Z.; Harff, J.; Böttcher, M.E.; Schulz-Bull, D.E., and Waniek, J.J., 2013. Regional differences of hydrographical and sedimentological properties in the Beibu Gulf, South China Sea. In: Harff, J., Leipe, T., Waniek, J.J., and Zhou, D. (eds.), Depositional Environments and Multiple Forcing Factors at the South China Sea's Northern Shelf, Journal of Coastal Research, Special Issue, No. 66, pp. 49–71. Coconut Creek (Florida), ISSN 0749-0208.Analyzing the Beibu Gulf's hydrography and sediment properties is crucial for the understanding of naturally and anthropogenically induced matter and energy fluxes in the South China Sea's north-western coastal regions. For this reason, the present study combines hydrographical (T, S, σt, chlorophyll, nutrients, suspended particulate matter) and sedimentological (grain size, pore water properties, phosphate speciation, foraminifera, plant pigment contents) investigations.On the basis of hydrographical profiles (temperature, salinity and σt) taken at 25 stations, four ecological zones are identified in the study area for the sampling period in September/October 2009. These zones are mainly influenced by riverine input and tidal mixing, water mass transport through the Qiongzhou Strait which also affects the gulf's circulation, and South China Sea waters in the southern Beibu Gulf. The zonation extends from the coastal areas in the northern Beibu Gulf and west of Hainan Island across the central regions to the southern part of the gulf. The study demonstrates that the hydrographical peculiarities of the different zones influence not only the biogeochemical features (chlorophyll, nutrients, suspended particulate matter) of the water column but also the deposition of sediments and their biological (plant pigment contents and foraminifera) and geochemical (pore water properties) characteristics. Both, the near-shore area and the zone in the vicinity of the Qiongzhou Strait show relatively high chlorophyll concentrations and therefore give evidence of enhanced primary production in the entire water column. Whereas the grain size and the foraminifera in the surface sediments follow the hydrodynamically controlled sedimentation conditions, plant pigment contents in the surface sediments additionally follow the productivity pattern in the water column. Depending on the depositional environments with their respective sedimentology and organic matter contents, the geochemical sediment properties reflect the primary production within the water column as well.

Digital soil mapping at pilot sites in the northwest coast of Egypt: A multinomial logistic regression approach

The study examines a digital soil mapping approach for the production of soil maps by using multinomial logistic regression on soil and terrain information at pilot sites in the Northwestern Coastal region of Egypt. The aim is to reproduce the original map and predict soil distribution in the adherent landscape. Reference soil maps produced by conventional methods at Omayed and Nagamish areas were used. Spectral and terrain parameters were calculated and logit models of the soil classes were developed. Predicted soil classes’ maps were produced. Software’s IDRISI/SAGA/SATISTCA/SPSS were used. The terrain and spectral parameters were found to be significantly influential and the selection of the land surfaces predictors was satisfactory. The McFadden pseudo R-squares ranged from 0.473 to 0.496. The most significant terrain parameters influencing the spatial distribution of the soil classes were elevation, valley depth, multiresolution ridgetop flatness index, multiresolution valley-bottom flatness index, and SAGA wetness index. However, the most influential spectral parameters are the first two principal components of the six Landsat Enhanced Thematic Mapper bands. The overall accuracy of the predicted soil maps ranged from 72% to 74% with a Kappa Index ranging from 0.62 to 0.64. The developed probability models were successfully used to predict the spatial distribution of the soil mapping units at pixel resolutions of 28.5 m × 28.5 m and 90 m × 90 m at adjacent unvisited areas at Matrouh and Alamin. The developed methodology could contribute to the allocation and to the soil digital mapping and management of new expansion sites in remote desert areas of Egypt.

Symbiotic nitrogen fixation in organically managed red clover–grass leys under farming conditions

Symbiotic nitrogen fixation (SNF) by legumes is an important source of N to agriculture, particularly under organic farming conditions. The objectives of this study were to document amounts of and variations in SNF under farming conditions in Finland, and to explore their determinants. SNF in perennial red clover–grass leys not amended with mineral N fertilizers was studied on 27 organic farms located in the southern and the north-western coastal regions of Finland. Ley growth subsequent to the harvest of the nurse crop fixed 38.6 kg N ha−1 yr−1 (SD = 25.2 kg N ha−1 yr−1). SNF in the accumulated first and second cuts of one- and two-year-old leys averaged 185.4 kg N ha−1 yr−1 (SD = 90.0 kg N ha−1 yr−1); fixation in the aftermath added 62.1 kg N ha−1 yr−1 (SD = 49.8 kg N ha−1 yr−1). SNF significantly increased from the first to the second cut. Owing to the poor persistence of clover, SNF declined with ley age. Between- and within-field coefficients of variation of SNF in one- and two-year-old leys averaged 51.1 and 51.8%, respectively, and increased with ley age. Variation of SNF within one- and two-year-old leys was significantly negatively related to amount of SNF on field level. SNF was significantly positively related to soil fertility parameters. Amounts of SNF were lower and between- and within-field variations of SNF were higher in the north-western as compared with the southern region. This difference was largely related to soil properties although the role of climate cannot be discarded. High between- and within-field variabilities of SNF suggest a need for amending within-field differences in soil fertility.

Studies on the sea cucumber fishery in the North Western coastal region of Sri Lanka

Official journal of the Sri Lanka Association for Fisheries and Aquatic Resources. Full text articles available here and on their own website, http://www.slafar.lk/index.php. Publication Frequency will be twice a year with two issues per volume, i.e., March (Issue 1) and September (Issue 2).

Radiation-use efficiency in leys: influences of growth period and clover proportion

Acquisition of carbohydrates and their partitioning to storage organs are decisive attributes for the persistence of perennial leys. It was therefore of interest to analyse radiation-use efficiency (RUE) and root allocation (br) in one-, two-, and three-year-old red clover–grass leys as functions of growth period (first and second growth, ley age), proportion of clover, and site properties (location, soil type, humus content). By calibrating RUE and br, the ley yields simulated with a growth model were adjusted to the values observed during two consecutive years at 33 organic farms located in the southern and the northwestern coastal regions of Finland. Driving variables of the simulations were daily measurements of weather. RUE declined from the first to the second growth and further with ley age, while its variability increased. The value of br decreased from the first to the second growth, and was positively correlated with RUE. The high variability of RUE between different sites, and the absence of correlations between site properties and RUE, were mainly attributable to differences in overwintering and regrowth conditions. Early measurements of above-ground biomass subsequent to overwintering and cutting, and the inclusion of site-specific measurements of soil properties would have increased the general validity of the calibrated parameter values. RUE correlated positively with proportion of clover. However, the increase of the proportion of clover from the first to the second growth was not strong enough to balance the concurrent decline of RUE. With increasing ley age there were two concurrent and reinforcing patterns, namely a decrease in proportion of clover and in RUE. Thus, both symbiotic N fixation and vigour of perennial red clover–grass leys declined with ley age. With regards to RUE, however, three-year-old leys were still productive.

Total mercury and monomethylmercury in water, sediments, and hydrophytes from the rivers, estuary, and bay along the Bohai Sea coast, northeastern China

Mercury contamination in aquatic environments is of worldwide concern because of its high biomagnification factor in food chains and long-range transport. The rivers, estuary and the bay along the northwestern Bohai Sea coast, northeastern China have been heavily contaminated by Hg due to long-term Zn smelting and chlor-alkali production. This work investigated the distributions of total Hg (THg) and smonomethylmercury (MMHg) in the water, sediment and hydrophytes from this area. Concentrations of THg in sediment (0.5-64 mg kg(-1)) and water (39-2700 ng L-1) were elevated by 1-3 orders of magnitude compared to background concentrations, which induced high concentrations of MMHg in these media. The highest concentration of MMHg in sediment reached 35 mu g kg-1. which was comparable to that in the Hg mining area, Wanshan, China, and the highest MMHg concentration of 3.0 ng L-1 in the water sample exceeded the MMHg Chinese drinking water guideline of 1.0 ng L-1. Concentrations of THg in a sediment profile from Jinzhou Bay were found to be consistent with annual Hg emission flux from a local Zn smelter (r = 0.74, p < 0.01), indicating that Hg contamination was mainly caused by Zn smelting locally. For some freshwater hydrophytes, concentrations of THg and MMHg ranged from 5.2 to 100 mu g kg(-1) and 0.15 to 12 mu g kg(-1), respectively. Compared to sediment, concentrations of THg in hydrophytes were 2-3 orders of magnitude lower but MMHg was comparable or higher, indicating that the bioaccumulation in plants was distinct for the two Hg species studied. The data suggest that a significant load of Hg has been released into the northwestern coastal region of the Bohai Sea. (C) 2009 Elsevier Ltd. All rights reserved.

Bathyergus suillus (Rodentia: Bathyergidae)

Bathyergus suillus (Schreber, 1782) is a bathyergid commonly known as the Cape dune mole-rat. A solitary-dwelling and sexually dimorphic species, it is the largest in body size of the African mole-rats, and 1 of 2 species within the genus. It is endemic to sandy soils of the southeastern and northwestern coastal regions of South Africa and the southwestern coast of Namibia. It is currently not of special conservation concern.

Weed occurrence in Finnish coastal regions: a survey of organically cropped spring cereals

Weed communities of organically cropped spring cereal stands in the southern and the northwestern coastal regions of Finland (= south and northwest, respectively) were compared with respect to number of species, frequency of occurrence, density and dry weight. Regional specialization of agricultural production along with differences in climate and soil properties were expected to generate differences in weed communities between south and northwest. Total and average numbers of species were higher in the south than in the northwest (33 vs. 26 and 15.6 vs. 10.0, respectively). Some rare species (e.g. Papaver dubium) were found in the south. Fumaria officinalis and Lamium spp. were found only in the south. The densities and dry weights of Lapsana communis, Myosotis arvensis, Polygonum aviculare, Tripleurospermum inodorum and Vicia spp. were higher in the south, while the densities and dry weights of Elymus repens, Persicaria spp. and Spergula arvensis were higher in the northwest. Total density of weeds did not differ between south and northwest (average = 565 vs. 570 shoots m-2, respectively). Total dry weight of weeds was higher in the northwest compared with the south (average = 1594 vs. 697 kg ha-1, respectively), mainly due to the high dry weight of E. repens. The only variable that was dependent on the duration of organic farming was weed density in the south. The abundance of nitrophilous in relation to non-nitrophilous weed species was higher while the abundance of perennial ruderal and grassland weed species was lower compared with previous weed surveys. This can be regarded as the result of increasing cropping intensity on organic farms in Finland. Different weed communities call for the application of specific target-oriented weed management in the respective coastal regions.;

Variability of herbage production in mixed leys as related to ley age and environmental factors: a farm survey

Influences of ley age, soil properties, and geographical location on the herbage production of red clover-grass leys were determined under practical conditions on 27 organic farms located in the southern and in the northwestern coastal regions of Finland. Averaged over one-, two-, and three-year-old leys the accumulated first and second cuts produced 7.12 t dry matter herbage ha-1 year-1, with a clover proportion of 34.8%. Herbage production declined with increasing ley age. The average proportion of clover increased from 26.4% in the first to 43.7% in the second cut but decreased with ley age. Within- and between-field variations of clover proportions markedly decreased from the first to the second cut and strongly increased with ley age, while changes in the variations of herbage production were less pronounced. Within-field variations of clover proportions in the first and in the second cuts were higher at lower proportions of clover. Herbage production was positively related with clover proportion. Soil properties had a major impact on clover proportion and herbage production, largely explaining also regional differences in ley growth. Amelioration of fields and, not at least, of less fertile sites within the same field seems to be a crucial requirement for higher and more even clover proportions and herbage yields.;