scholarly journals PENGARUH RESIDU PUPUK P PADA MT I TERHADAP STATUS P TANAH dan HASIL PADI SAWAH PADA MT II di KABUPATEN DHARMASRAYA SUMATERA BARAT Tinggi Di Kabupaten Dharmasya Sumatera Barat

Author(s):  
Ismon Lenin

<p align="center"><strong>ABSTRACT</strong><strong></strong></p><p><strong> E</strong><strong>ffectof</strong><strong> R</strong><strong>esidual</strong><strong> F</strong><strong>ertilizer</strong><strong> P </strong><strong>on</strong><strong> MTI </strong><strong>to</strong><strong> L</strong><strong>and</strong><strong> P S</strong><strong>tatusandResults Paddy Fieldon</strong><strong> MT II </strong><strong>in District Dharmasraya West Sumatera.</strong> Upland converted to paddy field, and intensively fertilized for 30 years causes the soil phosphorus (P) to be very high and the plant does not respond to the fertilization of  P. P fertilizer residues given in the previous planting season needs to be studied its utilization for the next planting. This study aimed to examine the effect of P fertilizer residue on MT I with high P status to P status and paddy rice yield on MT II in Dharmasraya Regency. The research was conducted from August - December 2013 on newly established paddy field in Dharmasraya District with Typic Hapludults soil type. The results showed that the application of P fertilizer at MT I with high rate on the high P status was proven to be utilized by plant on MT II. However, to obtain high productivity of the plant is still needed additional P fertilizer. The residue of P fertilizer on MT I can still be utilized to increase yield on MT II by 8.46% from 4,444 kg dried milled grain/ha to 4,820 kg dried milled grain/ha. The increase of P fertilizer rate no longer has a significant effect on the increase of dried grain yield.</p><p> p<em>addy, f</em><em>ertilizer,phosphorus, residual effect.</em><em></em></p><p><em> <br /></em></p><p align="center"><strong>ABSTRAK</strong></p><p>Lahan kering yang dikonversi menjadi sawah, dan diberi pupuk secara intensif selama 30 tahun menyebabkan kadar hara fosfor (P) tanah menjadi sangat tinggi dan tanaman tidak respon terhadap pemupukan P. Residu pupuk P yang diberikan pada musim tanam sebelumnya perlu dikaji pemanfaatannya untuk tanaman berikutnya. Penelitian ini bertujuan untuk menguji pengaruh residu pupuk P pada MT I pada lahan sawah berstatus P tinggi terhadap status P tanah dan hasil padi sawah pada MT II di Kabupaten Dharmasraya.  Penelitian dilaksanakan dari bulan Agustus - Desember 2013 pada sawah baru mapan di Kabupaten Dharmasraya dengan jenis tanah Typic Hapludults. Hasil pengkajian menunjukkan pemberian pupuk P pada MT I dengan dosis tinggi pada sawah dengan status P tinggi, terbukti masih bisa dimanfaatkan tanaman pada MT II. Namun demikian, untuk mendapatkan produktivitas tanaman yang tinggi masih diperlukan tambahan pupuk P. Residu pupuk P pada MT I masih dapat dimanfaatkan untuk meningkatkan hasil pada MT II sebesar 8,46% dari 4.444 kg GKG/ha menjadi 4.820  kg GKG/ha. Peningkatan takaran pupuk P selanjutnya tidak lagi berpengaruh nyata terhadap peningkatan hasil gabah kering giling.</p><p> <em>p</em><em>adi sawah, pemupukan, fosfor, pengaruh residu.</em><em></em></p>

2022 ◽  
Vol 20 (2) ◽  
pp. 219-230
Author(s):  
Erik Febriarta ◽  
Muh Aris Marfai ◽  
Dhandhun Wacano ◽  
Ajeng Larasati ◽  
Dyah Rahmawati Hizbaron

Fomasi litologi akuifer batugamping mempunyai karakteristik media aliran berupa celah, rekahan, dan lorong pelarutan, sehingga memiliki potensi mengalirkan airtanah dengan kecepatan tinggi. Produktivitas yang tinggi ini mengakibatkan sumber pencemar di permukaan dapat dengan cepat meresap ke sistem akuifer dan bercampur dengan airtanah; kondisi inilah yang memicu kerentanan tinggi. Salah satu langkah pengelolaan airtanah pesisir adalah penentuan zona kerentanan airtanah terhadap pencemaran. Dengan demikian, tujuan penelitian ini adalah untuk mengetahui tingkat kerentanan airtanah pesisir terhadap pencemaran di formasi batugamping menggunakan metode COP dengan pendekatan intrinsik dan metode EPIK dengan pendekatan perkembangan karst. Hasil penilaian menggunakan kedua metode tersebut menunjukkan tingkat kerentanan rendah hingga sangat tinggi. Pemetaan metode COP menghasilkan dua kelas kerentanan: rendah (95% dari luas wilayah) dan sedang (4%), sedangkan metode EPIK menghasilkan zona indeks kerentanan yang lebih panjang dengan empat kelas kerentanan, yaitu rendah (1,23%), sedang (17,82%), tinggi (17,82%), dan sangat tinggi (21,65%). Dibandingkan dengan COP, EPIK menghasilkan kelas kerentanan yang lebih tinggi karena pengaruh koefisien pembobot pada formula penghitungannya. Hasil penilaian kerentanan divalidasi dengan indikator limbah domestik berupa senyawa nitrat (NO3). Uji laboratorium menunjukkan kandungan nitrat (NO3) airtanah yang bervariasi dari 0,12 mg/l (terendah) hingga 9,80 mg/l (tertinggi). Variasi ini masih berada di bawah baku mutu air minum tetapi di atas baku mutu air limbah domestik atau melebihi kadar nitrat di alam. Berdasarkan hasil validasi, zona kerentanan berkorelasi dengan kandungan nitrat (NO3). Pada zona kerentanan yang tinggi, ditemukan kadar nitrat yang tinggi pula.ABSTRACTA limestone aquifer is lithologically characterized by three flow media: fissures, fractures, and dissolution channels, thus creating the potential to drain groundwater at a high rate. This high productivity, however, means that the groundwater is highly vulnerable to pollution. If a pollutant source is present on the surface, it can quickly seep into and mix with the subsurface system. Among the widely proposed management strategies is groundwater vulnerability zoning. This study was intended to determine the degrees of coastal groundwater vulnerability to pollution in a limestone formation with two methods: COP intrinsic vulnerability) and EPIK (karst development-based vulnerability). The assessment results showed that the vulnerability produced with both methods varied from low to very high. In the mapping, COP produced two levels: low (95% of the total area) and medium (4%), while EPIK generated a longer vulnerability index zone with four levels: low (1.23%), medium (17.82%), high (17.82%), and very high (21.65%). Compared to COP, EPIK results in a higher vulnerability class due to the weighting values in its vulnerability assessment. The results were validated with a domestic waste indicator: the presence of nitrate (NO3). Laboratory tests showed NO3 concentrations in the range 0.12 of 9.80 mg/l. These figures are still below the quality standard for drinking water but above that of domestic wastes or exceeding the maximum NO3 content found in nature. The validation revealed that the vulnerability zone is correlated with NO3 levels: the higher the vulnerability class of the zone, the higher the nitrate content.


<em>Abstract.</em>—The shortnose sturgeon, <em>Acipenser brevirostrum</em>, is a long-lived species that grows slowly, matures at an advanced age, and spawns only intermittently. In the Connecticut River, there are two distinct subpopulations of shortnose sturgeon, which have been separated by the Holyoke Dam for 157 years. My research addressed the viability and persistence for these two separate populations and the effects of dispersal, variation in survival and reproduction, and catastrophes. My risk-based approach used a stage-based metapopulation model that I constructed in RAMAS<sup>®</sup> GIS incorporating the available data. Based on the existing data, this population model for the shortnose sturgeon metapopulation in the Connecticut River made several predictions. The observed stability of the two subpopulations was possible either: with reproduction in both upper and lower subpopulations and small to moderate rates of dispersal between them; or with no reproduction in the lower subpopulation, very high reproduction in the upper subpopulation and high rate of net downstream dispersal. My results provided estimates of extinction risk for the shortnose sturgeon metapopulation under various management options and highlighted three key areas for future research, demonstrating the value of a risk-based approach. This approach is particularly useful for management of long-lived aquatic species.


Author(s):  
Avijit Gupta

Periodic attempts to plot global distribution of erosion and sedimentation usually attribute most of Southeast Asia with a very high sediment yield (Milliman and Meade 1983). The erosion rates and sediment yield figures are especially high for maritime Southeast Asia. Milliman and Syvitski (1992), for example, listed 3000 t km−2 yr−1 for the archipelagos and peninsulas of Southeast Asia. They provided a number of natural explanations for the high erosion rate: location near active plate margins, pyroclastic eruptions, steep slopes, and mass movements. This is also a region with considerable annual rainfall, a very substantial percentage of which tends to be concentrated in a few months and falls with high intensity. Part of Southeast Asia (the Philippines, Viet Nam, Timor) is visited by tropical cyclones with heavy, intense rainfall and possible associated wind damage to existing vegetation. The fans at the foot of slopes, the large volume of sediment stored in the channel and floodplain of the rivers, and the size of deltas all indicate a high rate of erosion and episodic sediment transfer. This episodic erosion and sediment transfer used to be controlled for most of the region by the thick cover of vegetation that once masked the slopes. When vegetation is removed soil and regolith de-structured, and natural slopes altered, the erosion rates and sediment yield reach high figures. Parts of Southeast Asia display striking anthropogenic alteration of the landscape, although the resulting accelerated erosion may be only temporary, operating on a scale of several years. Over time the affected zones shift, and slugs of sediment continue to arrive in a river but from different parts of its drainage basin. The combination of anthropogenic alteration and fragile landforms may give rise to very high local yields. Sediment yields of more than 15 000 t km−2 yr−1 have been estimated from such areas (Ruslan and Menam, cited in Lal 1987). This is undoubtedly towards the upper extreme, but current destruction of the vegetation cover due to deforestation, expansion of agriculture, mining, urbanization, and implementation of large-scale resettlement schemes has increased the sediment yield from < 102 to > 103 t km−2 yr−1.


2020 ◽  
pp. 75-82
Author(s):  
Josh E. Becker ◽  
E. Sherwood Brown

Bipolar disorder and substance use disorder co-occur at very high rates. The high rate is likely due to a complex interaction of biological, social, and psychological factors, and some research suggests that use of substances may be to mitigate symptoms associated with bipolar disorder. Some studies have shown that men with bipolar disorder may be at a higher risk for a substance use disorder than women. The co-occurrence of these disorders leads to poorer treatment outcomes because of higher rates of suicidality, poor treatment adherence, lower quality of life, and more frequent relapse. This population deserves special treatment consideration.


2018 ◽  
Vol 7 (2.6) ◽  
pp. 318
Author(s):  
Mandeep Virk ◽  
Vaishali Chauhan ◽  
Urvashi Mittal

Data analysis is the most grueling tasks in the coinciding world. The size of data is increasing at a very high rate because of the procreation of peripatetic gadgets and sensors attached. To make that data readable is another challenging task. Effectual visualization provides users with better analysis capabilities and helps in deriving evidence about data. Many techniques and tools have been invented to deal with such problems but to make these tools amendable is the main mystification. It is the big data that originated as a technology which is proficient in assembling and transforming the colossal and divergent figures of data, providing organizations with meaningful insights for derivingimprovedresults. Big data is accustomed to delineate technologies and techniques which are used to store, manage, distribute and analyze huge data sheets. The existent of administrating this research is to make the data readable in a more suitable form with less comprehend. Mainly the research emphasizes on the fabrication of using COGNOS insight 10.2.2 for visualizing data and implementing the analyzed results derived from the hive. The assimilation between tools has also been reformed in this research. 


2013 ◽  
Vol 59 (No. 4) ◽  
pp. 183-193 ◽  
Author(s):  
L. Smutka ◽  
J. Burianová

World trade underwent a significant shock within the recent years, which caused a decline in the world economy primarily in the year 2009. Within the following years (2010 and 2011), the high rate of growth from the years preceding the crisis could not be restored. The crisis had an impact on all segments of the merchandise trade, whereby the trade in agricultural and food products was affected the least by the crisis. In the case of the Czech Republic, the crisis of the global and national economy was reflected in the case of agricultural trade primarily by the way of a decline in the rate of the growth of export, which was very high in the period prior to the crisis. As far as the territorial structure and commodity structure of agricultural trade is concerned, their development in the years 2008&ndash;2011 was not affected in any largely significant manner. In relation to the main objective of this article, which was to identify the effects of the crisis on the competitiveness of Czech agricultural trade, it may be stated that the crisis itself did not worsen the competitiveness of agricultural trade in any significant manner. &nbsp;


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
C. Nobile ◽  
D. Houben ◽  
E. Michel ◽  
S. Firmin ◽  
H. Lambers ◽  
...  

Abstract Crops have different strategies to acquire poorly-available soil phosphorus (P) which are dependent on their architectural, morphological, and physiological root traits, but their capacity to enhance P acquisition varies with the type of fertilizer applied. The objective of this study was to examine how P-acquisition strategies of three main crops are affected by the application of sewage sludges, compared with a mineral P fertilizer. We carried out a 3-months greenhouse pot experiment and compared the response of P-acquisition traits among wheat, barley and canola in a soil amended with three sludges or a mineral P fertilizer. Results showed that the P-acquisition strategy differed among crops. Compared with canola, wheat and barley had a higher specific root length and a greater root carboxylate release and they acquired as much P from sludge as from mineral P. By contrast, canola shoot P content was greater with sludge than with mineral P. This was attributed to a higher root-released acid phosphatase activity which promoted the mineralization of sludge-derived P-organic. This study showed that contrasted P-acquisition strategies of crops allows increased use of renewable P resources by optimizing combinations of crop and the type of P fertilizer applied within the cropping system.


Author(s):  
Khaoula Ayati ◽  
Ramzi Hadjab ◽  
Hichem Khammar ◽  
Sonia Dhaouadi ◽  
Christophe Piscart ◽  
...  

Northern Africa, although one of the world hotpots of biodiversity, is poorly studied and the freshwater fauna living in this part of the world remains partly unknown. This study focused on the diversity and distribution of the poorly known epigean freshwater amphipods. We performed an exhaustive analysis of the literature on this group of crustaceans and sampled 106 additional localities from the eastern part of Algeria and in Tunisia. Our results showed an important diversity with 25 species (including the presence of at least three new undescribed species) and a very high rate of endemism with 52% of species occurring at on only 1 or 2 sites. We also highlighted a very low diversity on each site with only 4.4% of sites harboring more than 1 species. The comparative distribution of certain species between Europe and Maghreb and also between the western and eastern part of Northern Africa allow us to discuss some hypotheses about the factors underlying this endemism and the biogeographical origin of species. However, our study revealed a general lack of knowledge in the region, especially in the South of Morocco and Algeria. Hence, more information would be needed to propose adapted conservation strategies of freshwater fauna in Maghreb.


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